Skip various cmp-mem-const tests on lp64 hppa*-*-*

[official-gcc.git] / gcc / c / c-parser.cc

/* Parser for C and Objective-C.
   Copyright (C) 1987-2024 Free Software Foundation, Inc.

   Parser actions based on the old Bison parser; structure somewhat
   influenced by and fragments based on the C++ parser.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  */

/* TODO:

   Make sure all relevant comments, and all relevant code from all
   actions, brought over from old parser.  Verify exact correspondence
   of syntax accepted.

   Add testcases covering every input symbol in every state in old and
   new parsers.

   Include full syntax for GNU C, including erroneous cases accepted
   with error messages, in syntax productions in comments.

   Make more diagnostics in the front end generally take an explicit
   location rather than implicitly using input_location.  */

#include "config.h"
#define INCLUDE_MEMORY
#include "system.h"
#include "coretypes.h"
#include "target.h"
#include "function.h"
#include "c-tree.h"
#include "timevar.h"
#include "stringpool.h"
#include "cgraph.h"
#include "attribs.h"
#include "stor-layout.h"
#include "varasm.h"
#include "trans-mem.h"
#include "c-family/c-pragma.h"
#include "c-lang.h"
#include "c-family/c-objc.h"
#include "plugin.h"
#include "omp-general.h"
#include "omp-offload.h"
#include "builtins.h"
#include "gomp-constants.h"
#include "c-family/c-indentation.h"
#include "gimple-expr.h"
#include "context.h"
#include "gcc-rich-location.h"
#include "c-parser.h"
#include "gimple-parser.h"
#include "read-rtl-function.h"
#include "run-rtl-passes.h"
#include "intl.h"
#include "c-family/name-hint.h"
#include "tree-iterator.h"
#include "tree-pretty-print.h"
#include "memmodel.h"
#include "c-family/known-headers.h"
#include "bitmap.h"
#include "analyzer/analyzer-language.h"
#include "toplev.h"

/* We need to walk over decls with incomplete struct/union/enum types
   after parsing the whole translation unit.
   In finish_decl(), if the decl is static, has incomplete
   struct/union/enum type, it is appended to incomplete_record_decls.
   In c_parser_translation_unit(), we iterate over incomplete_record_decls
   and report error if any of the decls are still incomplete.  */ 

vec<tree> incomplete_record_decls;

void
set_c_expr_source_range (c_expr *expr,
                         location_t start, location_t finish)
{
  expr->src_range.m_start = start;
  expr->src_range.m_finish = finish;
  if (expr->value)
    set_source_range (expr->value, start, finish);
}

void
set_c_expr_source_range (c_expr *expr,
                         source_range src_range)
{
  expr->src_range = src_range;
  if (expr->value)
    set_source_range (expr->value, src_range);
}

\f
/* Initialization routine for this file.  */

void
c_parse_init (void)
{
  /* The only initialization required is of the reserved word
     identifiers.  */
  unsigned int i;
  tree id;
  int mask = 0;

  /* Make sure RID_MAX hasn't grown past the 8 bits used to hold the keyword in
     the c_token structure.  */
  gcc_assert (RID_MAX <= 255);

  mask |= D_CXXONLY;
  if (!flag_isoc99)
    mask |= D_C99;
  if (!flag_isoc23)
    mask |= D_C23;
  if (flag_no_asm)
    {
      mask |= D_ASM | D_EXT;
      if (!flag_isoc99)
        mask |= D_EXT89;
      if (!flag_isoc23)
        mask |= D_EXT11;
    }
  if (!c_dialect_objc ())
    mask |= D_OBJC | D_CXX_OBJC;

  ridpointers = ggc_cleared_vec_alloc<tree> ((int) RID_MAX);
  for (i = 0; i < num_c_common_reswords; i++)
    {
      /* If a keyword is disabled, do not enter it into the table
         and so create a canonical spelling that isn't a keyword.  */
      if (c_common_reswords[i].disable & mask)
        {
          if (warn_cxx_compat
              && (c_common_reswords[i].disable & D_CXXWARN))
            {
              id = get_identifier (c_common_reswords[i].word);
              C_SET_RID_CODE (id, RID_CXX_COMPAT_WARN);
              C_IS_RESERVED_WORD (id) = 1;
            }
          continue;
        }

      id = get_identifier (c_common_reswords[i].word);
      C_SET_RID_CODE (id, c_common_reswords[i].rid);
      C_IS_RESERVED_WORD (id) = 1;
      ridpointers [(int) c_common_reswords[i].rid] = id;
    }

  for (i = 0; i < NUM_INT_N_ENTS; i++)
    {
      /* We always create the symbols but they aren't always supported.  */
      char name[50];
      sprintf (name, "__int%d", int_n_data[i].bitsize);
      id = get_identifier (name);
      C_SET_RID_CODE (id, RID_FIRST_INT_N + i);
      C_IS_RESERVED_WORD (id) = 1;

      sprintf (name, "__int%d__", int_n_data[i].bitsize);
      id = get_identifier (name);
      C_SET_RID_CODE (id, RID_FIRST_INT_N + i);
      C_IS_RESERVED_WORD (id) = 1;
    }

  if (flag_openmp)
    {
      id = get_identifier ("omp_all_memory");
      C_SET_RID_CODE (id, RID_OMP_ALL_MEMORY);
      C_IS_RESERVED_WORD (id) = 1;
      ridpointers [RID_OMP_ALL_MEMORY] = id;
    }
}
\f
/* A parser structure recording information about the state and
   context of parsing.  Includes lexer information with up to two
   tokens of look-ahead; more are not needed for C.  */
struct GTY(()) c_parser {
  /* The look-ahead tokens.  */
  c_token * GTY((skip)) tokens;
  /* Buffer for look-ahead tokens.  */
  c_token tokens_buf[4];
  /* How many look-ahead tokens are available (0 - 4, or
     more if parsing from pre-lexed tokens).  */
  unsigned int tokens_avail;
  /* Raw look-ahead tokens, used only for checking in Objective-C
     whether '[[' starts attributes.  */
  vec<c_token, va_gc> *raw_tokens;
  /* The number of raw look-ahead tokens that have since been fully
     lexed.  */
  unsigned int raw_tokens_used;
  /* True if a syntax error is being recovered from; false otherwise.
     c_parser_error sets this flag.  It should clear this flag when
     enough tokens have been consumed to recover from the error.  */
  BOOL_BITFIELD error : 1;
  /* True if we're processing a pragma, and shouldn't automatically
     consume CPP_PRAGMA_EOL.  */
  BOOL_BITFIELD in_pragma : 1;
  /* True if we're parsing the outermost block of an if statement.  */
  BOOL_BITFIELD in_if_block : 1;
  /* True if we want to lex a translated, joined string (for an
     initial #pragma pch_preprocess).  Otherwise the parser is
     responsible for concatenating strings and translating to the
     execution character set as needed.  */
  BOOL_BITFIELD lex_joined_string : 1;
  /* True if, when the parser is concatenating string literals, it
     should translate them to the execution character set (false
     inside attributes).  */
  BOOL_BITFIELD translate_strings_p : 1;

  /* Objective-C specific parser/lexer information.  */

  /* True if we are in a context where the Objective-C "PQ" keywords
     are considered keywords.  */
  BOOL_BITFIELD objc_pq_context : 1;
  /* True if we are parsing a (potential) Objective-C foreach
     statement.  This is set to true after we parsed 'for (' and while
     we wait for 'in' or ';' to decide if it's a standard C for loop or an
     Objective-C foreach loop.  */
  BOOL_BITFIELD objc_could_be_foreach_context : 1;
  /* The following flag is needed to contextualize Objective-C lexical
     analysis.  In some cases (e.g., 'int NSObject;'), it is
     undesirable to bind an identifier to an Objective-C class, even
     if a class with that name exists.  */
  BOOL_BITFIELD objc_need_raw_identifier : 1;
  /* Nonzero if we're processing a __transaction statement.  The value
     is 1 | TM_STMT_ATTR_*.  */
  unsigned int in_transaction : 4;
  /* True if we are in a context where the Objective-C "Property attribute"
     keywords are valid.  */
  BOOL_BITFIELD objc_property_attr_context : 1;

  /* Whether we have just seen/constructed a string-literal.  Set when
     returning a string-literal from c_parser_string_literal.  Reset
     in consume_token.  Useful when we get a parse error and see an
     unknown token, which could have been a string-literal constant
     macro.  */
  BOOL_BITFIELD seen_string_literal : 1;

  /* TRUE if omp::directive, omp::decl or omp::sequence attributes may not
     appear.  */
  BOOL_BITFIELD omp_attrs_forbidden_p : 1;

  /* Location of the last consumed token.  */
  location_t last_token_location;

  /* Holds state for parsing collapsed OMP_FOR loops.  Managed by
     c_parser_omp_for_loop.  */
  struct omp_for_parse_data * GTY((skip)) omp_for_parse_state;

  /* If we're in the context of OpenMP directives written as C23
     attributes turned into pragma, vector of tokens created from that,
     otherwise NULL.  */
  vec<c_token, va_gc> *in_omp_attribute_pragma;

  /* Set for omp::decl attribute parsing to the decl to which it
     appertains.  */
  tree in_omp_decl_attribute;
};

/* Return a pointer to the Nth token in PARSERs tokens_buf.  */

c_token *
c_parser_tokens_buf (c_parser *parser, unsigned n)
{
  return &parser->tokens_buf[n];
}

/* Return the error state of PARSER.  */

bool
c_parser_error (c_parser *parser)
{
  return parser->error;
}

/* Set the error state of PARSER to ERR.  */

void
c_parser_set_error (c_parser *parser, bool err)
{
  parser->error = err;
}


/* The actual parser and external interface.  ??? Does this need to be
   garbage-collected?  */

static GTY (()) c_parser *the_parser;

/* Read in and lex a single token, storing it in *TOKEN.  If RAW,
   context-sensitive postprocessing of the token is not done.  */

static void
c_lex_one_token (c_parser *parser, c_token *token, bool raw = false)
{
  timevar_push (TV_LEX);

  if (raw || vec_safe_length (parser->raw_tokens) == 0)
    {
      token->type = c_lex_with_flags (&token->value, &token->location,
                                      &token->flags,
                                      (parser->lex_joined_string
                                       ? 0 : C_LEX_STRING_NO_JOIN));
      token->id_kind = C_ID_NONE;
      token->keyword = RID_MAX;
      token->pragma_kind = PRAGMA_NONE;
    }
  else
    {
      /* Use a token previously lexed as a raw look-ahead token, and
         complete the processing on it.  */
      *token = (*parser->raw_tokens)[parser->raw_tokens_used];
      ++parser->raw_tokens_used;
      if (parser->raw_tokens_used == vec_safe_length (parser->raw_tokens))
        {
          vec_free (parser->raw_tokens);
          parser->raw_tokens_used = 0;
        }
    }

  if (raw)
    goto out;

  switch (token->type)
    {
    case CPP_NAME:
      {
        tree decl;

        bool objc_force_identifier = parser->objc_need_raw_identifier;
        if (c_dialect_objc ())
          parser->objc_need_raw_identifier = false;

        if (C_IS_RESERVED_WORD (token->value))
          {
            enum rid rid_code = C_RID_CODE (token->value);

            if (rid_code == RID_CXX_COMPAT_WARN)
              {
                warning_at (token->location,
                            OPT_Wc___compat,
                            "identifier %qE conflicts with C++ keyword",
                            token->value);
              }
            else if (rid_code >= RID_FIRST_ADDR_SPACE
                     && rid_code <= RID_LAST_ADDR_SPACE)
              {
                addr_space_t as;
                as = (addr_space_t) (rid_code - RID_FIRST_ADDR_SPACE);
                targetm.addr_space.diagnose_usage (as, token->location);
                token->id_kind = C_ID_ADDRSPACE;
                token->keyword = rid_code;
                break;
              }
            else if (c_dialect_objc () && OBJC_IS_PQ_KEYWORD (rid_code))
              {
                /* We found an Objective-C "pq" keyword (in, out,
                   inout, bycopy, byref, oneway).  They need special
                   care because the interpretation depends on the
                   context.  */
                if (parser->objc_pq_context)
                  {
                    token->type = CPP_KEYWORD;
                    token->keyword = rid_code;
                    break;
                  }
                else if (parser->objc_could_be_foreach_context
                         && rid_code == RID_IN)
                  {
                    /* We are in Objective-C, inside a (potential)
                       foreach context (which means after having
                       parsed 'for (', but before having parsed ';'),
                       and we found 'in'.  We consider it the keyword
                       which terminates the declaration at the
                       beginning of a foreach-statement.  Note that
                       this means you can't use 'in' for anything else
                       in that context; in particular, in Objective-C
                       you can't use 'in' as the name of the running
                       variable in a C for loop.  We could potentially
                       try to add code here to disambiguate, but it
                       seems a reasonable limitation.  */
                    token->type = CPP_KEYWORD;
                    token->keyword = rid_code;
                    break;
                  }
                /* Else, "pq" keywords outside of the "pq" context are
                   not keywords, and we fall through to the code for
                   normal tokens.  */
              }
            else if (c_dialect_objc () && OBJC_IS_PATTR_KEYWORD (rid_code))
              {
                /* We found an Objective-C "property attribute"
                   keyword (getter, setter, readonly, etc). These are
                   only valid in the property context.  */
                if (parser->objc_property_attr_context)
                  {
                    token->type = CPP_KEYWORD;
                    token->keyword = rid_code;
                    break;
                  }
                /* Else they are not special keywords.
                */
              }
            else if (c_dialect_objc () 
                     && (OBJC_IS_AT_KEYWORD (rid_code)
                         || OBJC_IS_CXX_KEYWORD (rid_code)))
              {
                /* We found one of the Objective-C "@" keywords (defs,
                   selector, synchronized, etc) or one of the
                   Objective-C "cxx" keywords (class, private,
                   protected, public, try, catch, throw) without a
                   preceding '@' sign.  Do nothing and fall through to
                   the code for normal tokens (in C++ we would still
                   consider the CXX ones keywords, but not in C).  */
                ;
              }
            else
              {
                token->type = CPP_KEYWORD;
                token->keyword = rid_code;
                break;
              }
          }

        decl = lookup_name (token->value);
        if (decl)
          {
            if (TREE_CODE (decl) == TYPE_DECL)
              {
                token->id_kind = C_ID_TYPENAME;
                break;
              }
          }
        else if (c_dialect_objc ())
          {
            tree objc_interface_decl = objc_is_class_name (token->value);
            /* Objective-C class names are in the same namespace as
               variables and typedefs, and hence are shadowed by local
               declarations.  */
            if (objc_interface_decl
                && (!objc_force_identifier || global_bindings_p ()))
              {
                token->value = objc_interface_decl;
                token->id_kind = C_ID_CLASSNAME;
                break;
              }
          }
        token->id_kind = C_ID_ID;
      }
      break;
    case CPP_AT_NAME:
      /* This only happens in Objective-C; it must be a keyword.  */
      token->type = CPP_KEYWORD;
      switch (C_RID_CODE (token->value))
        {
          /* Replace 'class' with '@class', 'private' with '@private',
             etc.  This prevents confusion with the C++ keyword
             'class', and makes the tokens consistent with other
             Objective-C 'AT' keywords.  For example '@class' is
             reported as RID_AT_CLASS which is consistent with
             '@synchronized', which is reported as
             RID_AT_SYNCHRONIZED.
          */
        case RID_CLASS:     token->keyword = RID_AT_CLASS; break;
        case RID_PRIVATE:   token->keyword = RID_AT_PRIVATE; break;
        case RID_PROTECTED: token->keyword = RID_AT_PROTECTED; break;
        case RID_PUBLIC:    token->keyword = RID_AT_PUBLIC; break;
        case RID_THROW:     token->keyword = RID_AT_THROW; break;
        case RID_TRY:       token->keyword = RID_AT_TRY; break;
        case RID_CATCH:     token->keyword = RID_AT_CATCH; break;
        case RID_SYNCHRONIZED: token->keyword = RID_AT_SYNCHRONIZED; break;
        default:            token->keyword = C_RID_CODE (token->value);
        }
      break;
    case CPP_COLON:
    case CPP_COMMA:
    case CPP_CLOSE_PAREN:
    case CPP_SEMICOLON:
      /* These tokens may affect the interpretation of any identifiers
         following, if doing Objective-C.  */
      if (c_dialect_objc ())
        parser->objc_need_raw_identifier = false;
      break;
    case CPP_PRAGMA:
      /* We smuggled the cpp_token->u.pragma value in an INTEGER_CST.  */
      token->pragma_kind = (enum pragma_kind) TREE_INT_CST_LOW (token->value);
      token->value = NULL;
      break;
    default:
      break;
    }
 out:
  timevar_pop (TV_LEX);
}

/* Return a pointer to the next token from PARSER, reading it in if
   necessary.  */

c_token *
c_parser_peek_token (c_parser *parser)
{
  if (parser->tokens_avail == 0)
    {
      c_lex_one_token (parser, &parser->tokens[0]);
      parser->tokens_avail = 1;
    }
  return &parser->tokens[0];
}

/* Return a pointer to the next-but-one token from PARSER, reading it
   in if necessary.  The next token is already read in.  */

c_token *
c_parser_peek_2nd_token (c_parser *parser)
{
  if (parser->tokens_avail >= 2)
    return &parser->tokens[1];
  gcc_assert (parser->tokens_avail == 1);
  gcc_assert (parser->tokens[0].type != CPP_EOF);
  gcc_assert (parser->tokens[0].type != CPP_PRAGMA_EOL);
  c_lex_one_token (parser, &parser->tokens[1]);
  parser->tokens_avail = 2;
  return &parser->tokens[1];
}

/* Return a pointer to the Nth token from PARSER, reading it
   in if necessary.  The N-1th token is already read in.  */

c_token *
c_parser_peek_nth_token (c_parser *parser, unsigned int n)
{
  /* N is 1-based, not zero-based.  */
  gcc_assert (n > 0);

  if (parser->tokens_avail >= n)
    return &parser->tokens[n - 1];
  gcc_assert (parser->tokens_avail == n - 1);
  c_lex_one_token (parser, &parser->tokens[n - 1]);
  parser->tokens_avail = n;
  return &parser->tokens[n - 1];
}

/* Return a pointer to the Nth token from PARSER, reading it in as a
   raw look-ahead token if necessary.  The N-1th token is already read
   in.  Raw look-ahead tokens remain available for when the non-raw
   functions above are called.  */

c_token *
c_parser_peek_nth_token_raw (c_parser *parser, unsigned int n)
{
  /* N is 1-based, not zero-based.  */
  gcc_assert (n > 0);

  if (parser->tokens_avail >= n)
    return &parser->tokens[n - 1];
  unsigned int raw_len = vec_safe_length (parser->raw_tokens);
  unsigned int raw_avail
    = parser->tokens_avail + raw_len - parser->raw_tokens_used;
  gcc_assert (raw_avail >= n - 1);
  if (raw_avail >= n)
    return &(*parser->raw_tokens)[parser->raw_tokens_used
                                  + n - 1 - parser->tokens_avail];
  vec_safe_reserve (parser->raw_tokens, 1);
  parser->raw_tokens->quick_grow (raw_len + 1);
  c_lex_one_token (parser, &(*parser->raw_tokens)[raw_len], true);
  return &(*parser->raw_tokens)[raw_len];
}

bool
c_keyword_starts_typename (enum rid keyword)
{
  switch (keyword)
    {
    case RID_UNSIGNED:
    case RID_LONG:
    case RID_SHORT:
    case RID_SIGNED:
    case RID_COMPLEX:
    case RID_INT:
    case RID_CHAR:
    case RID_FLOAT:
    case RID_DOUBLE:
    case RID_VOID:
    case RID_DFLOAT32:
    case RID_DFLOAT64:
    case RID_DFLOAT128:
    CASE_RID_FLOATN_NX:
    case RID_BOOL:
    case RID_BITINT:
    case RID_ENUM:
    case RID_STRUCT:
    case RID_UNION:
    case RID_TYPEOF:
    case RID_TYPEOF_UNQUAL:
    case RID_CONST:
    case RID_ATOMIC:
    case RID_VOLATILE:
    case RID_RESTRICT:
    case RID_ATTRIBUTE:
    case RID_FRACT:
    case RID_ACCUM:
    case RID_SAT:
    case RID_AUTO_TYPE:
    case RID_ALIGNAS:
      return true;
    default:
      if (keyword >= RID_FIRST_INT_N
          && keyword < RID_FIRST_INT_N + NUM_INT_N_ENTS
          && int_n_enabled_p[keyword - RID_FIRST_INT_N])
        return true;
      return false;
    }
}

/* Return true if TOKEN can start a type name,
   false otherwise.  */
bool
c_token_starts_typename (c_token *token)
{
  switch (token->type)
    {
    case CPP_NAME:
      switch (token->id_kind)
        {
        case C_ID_ID:
          return false;
        case C_ID_ADDRSPACE:
          return true;
        case C_ID_TYPENAME:
          return true;
        case C_ID_CLASSNAME:
          gcc_assert (c_dialect_objc ());
          return true;
        default:
          gcc_unreachable ();
        }
    case CPP_KEYWORD:
      return c_keyword_starts_typename (token->keyword);
    case CPP_LESS:
      if (c_dialect_objc ())
        return true;
      return false;
    default:
      return false;
    }
}

/* Return true if the next token from PARSER can start a type name,
   false otherwise.  LA specifies how to do lookahead in order to
   detect unknown type names.  If unsure, pick CLA_PREFER_ID.  */

static inline bool
c_parser_next_tokens_start_typename (c_parser *parser, enum c_lookahead_kind la)
{
  c_token *token = c_parser_peek_token (parser);
  if (c_token_starts_typename (token))
    return true;

  /* Try a bit harder to detect an unknown typename.  */
  if (la != cla_prefer_id
      && token->type == CPP_NAME
      && token->id_kind == C_ID_ID

      /* Do not try too hard when we could have "object in array".  */
      && !parser->objc_could_be_foreach_context

      && (la == cla_prefer_type
          || c_parser_peek_2nd_token (parser)->type == CPP_NAME
          || c_parser_peek_2nd_token (parser)->type == CPP_MULT)

      /* Only unknown identifiers.  */
      && !lookup_name (token->value))
    return true;

  return false;
}

/* Return true if TOKEN, after an open parenthesis, can start a
   compound literal (either a storage class specifier allowed in that
   context, or a type name), false otherwise.  */
static bool
c_token_starts_compound_literal (c_token *token)
{
  switch (token->type)
    {
    case CPP_KEYWORD:
      switch (token->keyword)
        {
        case RID_CONSTEXPR:
        case RID_REGISTER:
        case RID_STATIC:
        case RID_THREAD:
          return true;
        default:
          break;
        }
      /* Fall through.  */
    default:
      return c_token_starts_typename (token);
    }
}

/* Return true if TOKEN is a type qualifier, false otherwise.  */
static bool
c_token_is_qualifier (c_token *token)
{
  switch (token->type)
    {
    case CPP_NAME:
      switch (token->id_kind)
        {
        case C_ID_ADDRSPACE:
          return true;
        default:
          return false;
        }
    case CPP_KEYWORD:
      switch (token->keyword)
        {
        case RID_CONST:
        case RID_VOLATILE:
        case RID_RESTRICT:
        case RID_ATTRIBUTE:
        case RID_ATOMIC:
          return true;
        default:
          return false;
        }
    case CPP_LESS:
      return false;
    default:
      gcc_unreachable ();
    }
}

/* Return true if the next token from PARSER is a type qualifier,
   false otherwise.  */
static inline bool
c_parser_next_token_is_qualifier (c_parser *parser)
{
  c_token *token = c_parser_peek_token (parser);
  return c_token_is_qualifier (token);
}

/* Return true if TOKEN can start declaration specifiers (not
   including standard attributes), false otherwise.  */
static bool
c_token_starts_declspecs (c_token *token)
{
  switch (token->type)
    {
    case CPP_NAME:
      switch (token->id_kind)
        {
        case C_ID_ID:
          return false;
        case C_ID_ADDRSPACE:
          return true;
        case C_ID_TYPENAME:
          return true;
        case C_ID_CLASSNAME:
          gcc_assert (c_dialect_objc ());
          return true;
        default:
          gcc_unreachable ();
        }
    case CPP_KEYWORD:
      switch (token->keyword)
        {
        case RID_STATIC:
        case RID_EXTERN:
        case RID_REGISTER:
        case RID_TYPEDEF:
        case RID_INLINE:
        case RID_NORETURN:
        case RID_AUTO:
        case RID_THREAD:
        case RID_UNSIGNED:
        case RID_LONG:
        case RID_SHORT:
        case RID_SIGNED:
        case RID_COMPLEX:
        case RID_INT:
        case RID_CHAR:
        case RID_FLOAT:
        case RID_DOUBLE:
        case RID_VOID:
        case RID_DFLOAT32:
        case RID_DFLOAT64:
        case RID_DFLOAT128:
        CASE_RID_FLOATN_NX:
        case RID_BOOL:
        case RID_BITINT:
        case RID_ENUM:
        case RID_STRUCT:
        case RID_UNION:
        case RID_TYPEOF:
        case RID_TYPEOF_UNQUAL:
        case RID_CONST:
        case RID_VOLATILE:
        case RID_RESTRICT:
        case RID_ATTRIBUTE:
        case RID_FRACT:
        case RID_ACCUM:
        case RID_SAT:
        case RID_ALIGNAS:
        case RID_ATOMIC:
        case RID_AUTO_TYPE:
        case RID_CONSTEXPR:
          return true;
        default:
          if (token->keyword >= RID_FIRST_INT_N
              && token->keyword < RID_FIRST_INT_N + NUM_INT_N_ENTS
              && int_n_enabled_p[token->keyword - RID_FIRST_INT_N])
            return true;
          return false;
        }
    case CPP_LESS:
      if (c_dialect_objc ())
        return true;
      return false;
    default:
      return false;
    }
}


/* Return true if TOKEN can start declaration specifiers (not
   including standard attributes) or a static assertion, false
   otherwise.  */
static bool
c_token_starts_declaration (c_token *token)
{
  if (c_token_starts_declspecs (token)
      || token->keyword == RID_STATIC_ASSERT)
    return true;
  else
    return false;
}

/* Return true if the next token from PARSER can start declaration
   specifiers (not including standard attributes), false
   otherwise.  */
bool
c_parser_next_token_starts_declspecs (c_parser *parser)
{
  c_token *token = c_parser_peek_token (parser);

  /* In Objective-C, a classname normally starts a declspecs unless it
     is immediately followed by a dot.  In that case, it is the
     Objective-C 2.0 "dot-syntax" for class objects, ie, calls the
     setter/getter on the class.  c_token_starts_declspecs() can't
     differentiate between the two cases because it only checks the
     current token, so we have a special check here.  */
  if (c_dialect_objc () 
      && token->type == CPP_NAME
      && token->id_kind == C_ID_CLASSNAME 
      && c_parser_peek_2nd_token (parser)->type == CPP_DOT)
    return false;

  return c_token_starts_declspecs (token);
}

/* Return true if the next tokens from PARSER can start declaration
   specifiers (not including standard attributes) or a static
   assertion, false otherwise.  */
bool
c_parser_next_tokens_start_declaration (c_parser *parser)
{
  c_token *token = c_parser_peek_token (parser);

  /* Same as above.  */
  if (c_dialect_objc () 
      && token->type == CPP_NAME
      && token->id_kind == C_ID_CLASSNAME 
      && c_parser_peek_2nd_token (parser)->type == CPP_DOT)
    return false;

  /* Labels do not start declarations.  */
  if (token->type == CPP_NAME
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    return false;

  if (c_token_starts_declaration (token))
    return true;

  if (c_parser_next_tokens_start_typename (parser, cla_nonabstract_decl))
    return true;

  return false;
}

/* Consume the next token from PARSER.  */

void
c_parser_consume_token (c_parser *parser)
{
  gcc_assert (parser->tokens_avail >= 1);
  gcc_assert (parser->tokens[0].type != CPP_EOF);
  gcc_assert (!parser->in_pragma || parser->tokens[0].type != CPP_PRAGMA_EOL);
  gcc_assert (parser->error || parser->tokens[0].type != CPP_PRAGMA);
  parser->last_token_location = parser->tokens[0].location;
  if (parser->tokens != &parser->tokens_buf[0])
    parser->tokens++;
  else if (parser->tokens_avail >= 2)
    {
      parser->tokens[0] = parser->tokens[1];
      if (parser->tokens_avail >= 3)
        {
          parser->tokens[1] = parser->tokens[2];
          if (parser->tokens_avail >= 4)
            parser->tokens[2] = parser->tokens[3];
        }
    }
  parser->tokens_avail--;
  parser->seen_string_literal = false;
}

/* Expect the current token to be a #pragma.  Consume it and remember
   that we've begun parsing a pragma.  */

static void
c_parser_consume_pragma (c_parser *parser)
{
  gcc_assert (!parser->in_pragma);
  gcc_assert (parser->tokens_avail >= 1);
  gcc_assert (parser->tokens[0].type == CPP_PRAGMA);
  if (parser->tokens != &parser->tokens_buf[0])
    parser->tokens++;
  else if (parser->tokens_avail >= 2)
    {
      parser->tokens[0] = parser->tokens[1];
      if (parser->tokens_avail >= 3)
        parser->tokens[1] = parser->tokens[2];
    }
  parser->tokens_avail--;
  parser->in_pragma = true;
}

/* Update the global input_location from TOKEN.  */
static inline void
c_parser_set_source_position_from_token (c_token *token)
{
  if (token->type != CPP_EOF)
    {
      input_location = token->location;
    }
}

/* Helper function for c_parser_error.
   Having peeked a token of kind TOK1_KIND that might signify
   a conflict marker, peek successor tokens to determine
   if we actually do have a conflict marker.
   Specifically, we consider a run of 7 '<', '=' or '>' characters
   at the start of a line as a conflict marker.
   These come through the lexer as three pairs and a single,
   e.g. three CPP_LSHIFT ("<<") and a CPP_LESS ('<').
   If it returns true, *OUT_LOC is written to with the location/range
   of the marker.  */

static bool
c_parser_peek_conflict_marker (c_parser *parser, enum cpp_ttype tok1_kind,
                               location_t *out_loc)
{
  c_token *token2 = c_parser_peek_2nd_token (parser);
  if (token2->type != tok1_kind)
    return false;
  c_token *token3 = c_parser_peek_nth_token (parser, 3);
  if (token3->type != tok1_kind)
    return false;
  c_token *token4 = c_parser_peek_nth_token (parser, 4);
  if (token4->type != conflict_marker_get_final_tok_kind (tok1_kind))
    return false;

  /* It must be at the start of the line.  */
  location_t start_loc = c_parser_peek_token (parser)->location;
  if (LOCATION_COLUMN (start_loc) != 1)
    return false;

  /* We have a conflict marker.  Construct a location of the form:
       <<<<<<<
       ^~~~~~~
     with start == caret, finishing at the end of the marker.  */
  location_t finish_loc = get_finish (token4->location);
  *out_loc = make_location (start_loc, start_loc, finish_loc);

  return true;
}

/* Issue a diagnostic of the form
      FILE:LINE: MESSAGE before TOKEN
   where TOKEN is the next token in the input stream of PARSER.
   MESSAGE (specified by the caller) is usually of the form "expected
   OTHER-TOKEN".

   Use RICHLOC as the location of the diagnostic.

   Do not issue a diagnostic if still recovering from an error.

   Return true iff an error was actually emitted.

   ??? This is taken from the C++ parser, but building up messages in
   this way is not i18n-friendly and some other approach should be
   used.  */

static bool
c_parser_error_richloc (c_parser *parser, const char *gmsgid,
                        rich_location *richloc)
{
  c_token *token = c_parser_peek_token (parser);
  if (parser->error)
    return false;
  parser->error = true;
  if (!gmsgid)
    return false;

  /* If this is actually a conflict marker, report it as such.  */
  if (token->type == CPP_LSHIFT
      || token->type == CPP_RSHIFT
      || token->type == CPP_EQ_EQ)
    {
      location_t loc;
      if (c_parser_peek_conflict_marker (parser, token->type, &loc))
        {
          error_at (loc, "version control conflict marker in file");
          return true;
        }
    }

  /* If we were parsing a string-literal and there is an unknown name
     token right after, then check to see if that could also have been
     a literal string by checking the name against a list of known
     standard string literal constants defined in header files. If
     there is one, then add that as an hint to the error message. */
  auto_diagnostic_group d;
  name_hint h;
  if (parser->seen_string_literal && token->type == CPP_NAME)
    {
      tree name = token->value;
      const char *token_name = IDENTIFIER_POINTER (name);
      const char *header_hint
        = get_c_stdlib_header_for_string_macro_name (token_name);
      if (header_hint != NULL)
        h = name_hint (NULL, new suggest_missing_header (token->location,
                                                         token_name,
                                                         header_hint));
    }

  c_parse_error (gmsgid,
                 /* Because c_parse_error does not understand
                    CPP_KEYWORD, keywords are treated like
                    identifiers.  */
                 (token->type == CPP_KEYWORD ? CPP_NAME : token->type),
                 /* ??? The C parser does not save the cpp flags of a
                    token, we need to pass 0 here and we will not get
                    the source spelling of some tokens but rather the
                    canonical spelling.  */
                 token->value, /*flags=*/0, richloc);
  return true;
}

/* As c_parser_error_richloc, but issue the message at the
   location of PARSER's next token, or at input_location
   if the next token is EOF.  */

bool
c_parser_error (c_parser *parser, const char *gmsgid)
{
  c_token *token = c_parser_peek_token (parser);
  c_parser_set_source_position_from_token (token);
  rich_location richloc (line_table, input_location);
  return c_parser_error_richloc (parser, gmsgid, &richloc);
}

/* Some tokens naturally come in pairs e.g.'(' and ')'.
   This class is for tracking such a matching pair of symbols.
   In particular, it tracks the location of the first token,
   so that if the second token is missing, we can highlight the
   location of the first token when notifying the user about the
   problem.  */

template <typename traits_t>
class token_pair
{
 public:
  /* token_pair's ctor.  */
  token_pair () : m_open_loc (UNKNOWN_LOCATION) {}

  /* If the next token is the opening symbol for this pair, consume it and
     return true.
     Otherwise, issue an error and return false.
     In either case, record the location of the opening token.  */

  bool require_open (c_parser *parser)
  {
    c_token *token = c_parser_peek_token (parser);
    if (token)
      m_open_loc = token->location;

    return c_parser_require (parser, traits_t::open_token_type,
                             traits_t::open_gmsgid);
  }

  /* Consume the next token from PARSER, recording its location as
     that of the opening token within the pair.  */

  void consume_open (c_parser *parser)
  {
    c_token *token = c_parser_peek_token (parser);
    gcc_assert (token->type == traits_t::open_token_type);
    m_open_loc = token->location;
    c_parser_consume_token (parser);
  }

  /* If the next token is the closing symbol for this pair, consume it
     and return true.
     Otherwise, issue an error, highlighting the location of the
     corresponding opening token, and return false.  */

  bool require_close (c_parser *parser) const
  {
    return c_parser_require (parser, traits_t::close_token_type,
                             traits_t::close_gmsgid, m_open_loc);
  }

  /* Like token_pair::require_close, except that tokens will be skipped
     until the desired token is found.  An error message is still produced
     if the next token is not as expected.  */

  void skip_until_found_close (c_parser *parser) const
  {
    c_parser_skip_until_found (parser, traits_t::close_token_type,
                               traits_t::close_gmsgid, m_open_loc);
  }

 private:
  location_t m_open_loc;
};

/* Traits for token_pair<T> for tracking matching pairs of parentheses.  */

struct matching_paren_traits
{
  static const enum cpp_ttype open_token_type = CPP_OPEN_PAREN;
  static const char * const open_gmsgid;
  static const enum cpp_ttype close_token_type = CPP_CLOSE_PAREN;
  static const char * const close_gmsgid;
};

const char * const matching_paren_traits::open_gmsgid = "expected %<(%>";
const char * const matching_paren_traits::close_gmsgid = "expected %<)%>";

/* "matching_parens" is a token_pair<T> class for tracking matching
   pairs of parentheses.  */

typedef token_pair<matching_paren_traits> matching_parens;

/* Traits for token_pair<T> for tracking matching pairs of braces.  */

struct matching_brace_traits
{
  static const enum cpp_ttype open_token_type = CPP_OPEN_BRACE;
  static const char * const open_gmsgid;
  static const enum cpp_ttype close_token_type = CPP_CLOSE_BRACE;
  static const char * const close_gmsgid;
};

const char * const matching_brace_traits::open_gmsgid = "expected %<{%>";
const char * const matching_brace_traits::close_gmsgid = "expected %<}%>";

/* "matching_braces" is a token_pair<T> class for tracking matching
   pairs of braces.  */

typedef token_pair<matching_brace_traits> matching_braces;

/* Get a description of the matching symbol to TYPE e.g. "(" for
   CPP_CLOSE_PAREN.  */

static const char *
get_matching_symbol (enum cpp_ttype type)
{
  switch (type)
    {
    default:
      gcc_unreachable ();
    case CPP_CLOSE_PAREN:
      return "(";
    case CPP_CLOSE_BRACE:
      return "{";
    }
}

/* If the next token is of the indicated TYPE, consume it.  Otherwise,
   issue the error MSGID.  If MSGID is NULL then a message has already
   been produced and no message will be produced this time.  Returns
   true if found, false otherwise.

   If MATCHING_LOCATION is not UNKNOWN_LOCATION, then highlight it
   within any error as the location of an "opening" token matching
   the close token TYPE (e.g. the location of the '(' when TYPE is
   CPP_CLOSE_PAREN).

   If TYPE_IS_UNIQUE is true (the default) then msgid describes exactly
   one type (e.g. "expected %<)%>") and thus it may be reasonable to
   attempt to generate a fix-it hint for the problem.
   Otherwise msgid describes multiple token types (e.g.
   "expected %<;%>, %<,%> or %<)%>"), and thus we shouldn't attempt to
   generate a fix-it hint.  */

bool
c_parser_require (c_parser *parser,
                  enum cpp_ttype type,
                  const char *msgid,
                  location_t matching_location,
                  bool type_is_unique)
{
  if (c_parser_next_token_is (parser, type))
    {
      c_parser_consume_token (parser);
      return true;
    }
  else
    {
      location_t next_token_loc = c_parser_peek_token (parser)->location;
      gcc_rich_location richloc (next_token_loc);

      /* Potentially supply a fix-it hint, suggesting to add the
         missing token immediately after the *previous* token.
         This may move the primary location within richloc.  */
      if (!parser->error && type_is_unique)
        maybe_suggest_missing_token_insertion (&richloc, type,
                                               parser->last_token_location);

      /* If matching_location != UNKNOWN_LOCATION, highlight it.
         Attempt to consolidate diagnostics by printing it as a
         secondary range within the main diagnostic.  */
      bool added_matching_location = false;
      if (matching_location != UNKNOWN_LOCATION)
        added_matching_location
          = richloc.add_location_if_nearby (matching_location);

      if (c_parser_error_richloc (parser, msgid, &richloc))
        /* If we weren't able to consolidate matching_location, then
           print it as a secondary diagnostic.  */
        if (matching_location != UNKNOWN_LOCATION && !added_matching_location)
          inform (matching_location, "to match this %qs",
                  get_matching_symbol (type));

      return false;
    }
}

/* If the next token is the indicated keyword, consume it.  Otherwise,
   issue the error MSGID.  Returns true if found, false otherwise.  */

static bool
c_parser_require_keyword (c_parser *parser,
                          enum rid keyword,
                          const char *msgid)
{
  if (c_parser_next_token_is_keyword (parser, keyword))
    {
      c_parser_consume_token (parser);
      return true;
    }
  else
    {
      c_parser_error (parser, msgid);
      return false;
    }
}

/* Like c_parser_require, except that tokens will be skipped until the
   desired token is found.  An error message is still produced if the
   next token is not as expected.  If MSGID is NULL then a message has
   already been produced and no message will be produced this
   time.

   If MATCHING_LOCATION is not UNKNOWN_LOCATION, then highlight it
   within any error as the location of an "opening" token matching
   the close token TYPE (e.g. the location of the '(' when TYPE is
   CPP_CLOSE_PAREN).  */

void
c_parser_skip_until_found (c_parser *parser,
                           enum cpp_ttype type,
                           const char *msgid,
                           location_t matching_location)
{
  unsigned nesting_depth = 0;

  if (c_parser_require (parser, type, msgid, matching_location))
    {
      if (UNLIKELY (type == CPP_PRAGMA_EOL) && parser->in_omp_attribute_pragma)
        {
          c_token *token = c_parser_peek_token (parser);
          if (token->type == CPP_EOF)
            {
              parser->tokens = &parser->tokens_buf[0];
              parser->tokens_avail = token->flags;
              parser->in_omp_attribute_pragma = NULL;
            }
        }
      return;
    }

  /* Skip tokens until the desired token is found.  */
  while (true)
    {
      /* Peek at the next token.  */
      c_token *token = c_parser_peek_token (parser);
      /* If we've reached the token we want, consume it and stop.  */
      if (token->type == type && !nesting_depth)
        {
          c_parser_consume_token (parser);
          if (UNLIKELY (type == CPP_PRAGMA_EOL)
              && parser->in_omp_attribute_pragma)
            {
              c_token *token = c_parser_peek_token (parser);
              if (token->type == CPP_EOF)
                {
                  parser->tokens = &parser->tokens_buf[0];
                  parser->tokens_avail = token->flags;
                  parser->in_omp_attribute_pragma = NULL;
                }
            }
          break;
        }

      /* If we've run out of tokens, stop.  */
      if (token->type == CPP_EOF)
        return;
      if (token->type == CPP_PRAGMA_EOL && parser->in_pragma)
        return;
      if (token->type == CPP_OPEN_BRACE
          || token->type == CPP_OPEN_PAREN
          || token->type == CPP_OPEN_SQUARE)
        ++nesting_depth;
      else if (token->type == CPP_CLOSE_BRACE
               || token->type == CPP_CLOSE_PAREN
               || token->type == CPP_CLOSE_SQUARE)
        {
          if (nesting_depth-- == 0)
            break;
        }
      /* Consume this token.  */
      c_parser_consume_token (parser);
    }
  parser->error = false;
}

/* Skip tokens until the end of a parameter is found, but do not
   consume the comma, semicolon or closing delimiter.  */

static void
c_parser_skip_to_end_of_parameter (c_parser *parser)
{
  unsigned nesting_depth = 0;

  while (true)
    {
      c_token *token = c_parser_peek_token (parser);
      if ((token->type == CPP_COMMA || token->type == CPP_SEMICOLON)
          && !nesting_depth)
        break;
      /* If we've run out of tokens, stop.  */
      if (token->type == CPP_EOF)
        return;
      if (token->type == CPP_PRAGMA_EOL && parser->in_pragma)
        return;
      if (token->type == CPP_OPEN_BRACE
          || token->type == CPP_OPEN_PAREN
          || token->type == CPP_OPEN_SQUARE)
        ++nesting_depth;
      else if (token->type == CPP_CLOSE_BRACE
               || token->type == CPP_CLOSE_PAREN
               || token->type == CPP_CLOSE_SQUARE)
        {
          if (nesting_depth-- == 0)
            break;
        }
      /* Consume this token.  */
      c_parser_consume_token (parser);
    }
  parser->error = false;
}

/* Expect to be at the end of the pragma directive and consume an
   end of line marker.  */

static void
c_parser_skip_to_pragma_eol (c_parser *parser, bool error_if_not_eol = true)
{
  gcc_assert (parser->in_pragma);
  parser->in_pragma = false;

  if (error_if_not_eol && c_parser_peek_token (parser)->type != CPP_PRAGMA_EOL)
    c_parser_error (parser, "expected end of line");

  cpp_ttype token_type;
  do
    {
      c_token *token = c_parser_peek_token (parser);
      token_type = token->type;
      if (token_type == CPP_EOF)
        break;
      c_parser_consume_token (parser);
    }
  while (token_type != CPP_PRAGMA_EOL);

  if (parser->in_omp_attribute_pragma)
    {
      c_token *token = c_parser_peek_token (parser);
      if (token->type == CPP_EOF)
        {
          parser->tokens = &parser->tokens_buf[0];
          parser->tokens_avail = token->flags;
          parser->in_omp_attribute_pragma = NULL;
        }
    }

  parser->error = false;
}

/* Skip tokens until we have consumed an entire block, or until we
   have consumed a non-nested ';'.  */

static void
c_parser_skip_to_end_of_block_or_statement (c_parser *parser)
{
  unsigned nesting_depth = 0;
  bool save_error = parser->error;

  while (true)
    {
      c_token *token;

      /* Peek at the next token.  */
      token = c_parser_peek_token (parser);

      switch (token->type)
        {
        case CPP_EOF:
          return;

        case CPP_PRAGMA_EOL:
          if (parser->in_pragma)
            return;
          break;

        case CPP_SEMICOLON:
          /* If the next token is a ';', we have reached the
             end of the statement.  */
          if (!nesting_depth)
            {
              /* Consume the ';'.  */
              c_parser_consume_token (parser);
              goto finished;
            }
          break;

        case CPP_CLOSE_BRACE:
          /* If the next token is a non-nested '}', then we have
             reached the end of the current block.  */
          if (nesting_depth == 0 || --nesting_depth == 0)
            {
              c_parser_consume_token (parser);
              goto finished;
            }
          break;

        case CPP_OPEN_BRACE:
          /* If it the next token is a '{', then we are entering a new
             block.  Consume the entire block.  */
          ++nesting_depth;
          break;

        case CPP_PRAGMA:
          /* If we see a pragma, consume the whole thing at once.  We
             have some safeguards against consuming pragmas willy-nilly.
             Normally, we'd expect to be here with parser->error set,
             which disables these safeguards.  But it's possible to get
             here for secondary error recovery, after parser->error has
             been cleared.  */
          c_parser_consume_pragma (parser);
          c_parser_skip_to_pragma_eol (parser);
          parser->error = save_error;
          continue;

        default:
          break;
        }

      c_parser_consume_token (parser);
    }

 finished:
  parser->error = false;
}

/* CPP's options (initialized by c-opts.cc).  */
extern cpp_options *cpp_opts;

/* Save the warning flags which are controlled by __extension__.  */

static inline int
disable_extension_diagnostics (void)
{
  int ret = (pedantic
             | (warn_pointer_arith << 1)
             | (warn_traditional << 2)
             | (flag_iso << 3)
             | (warn_long_long << 4)
             | (warn_cxx_compat << 5)
             | (warn_overlength_strings << 6)
             /* warn_c90_c99_compat has three states: -1/0/1, so we must
                play tricks to properly restore it.  */
             | ((warn_c90_c99_compat == 1) << 7)
             | ((warn_c90_c99_compat == -1) << 8)
             /* Similarly for warn_c99_c11_compat.  */
             | ((warn_c99_c11_compat == 1) << 9)
             | ((warn_c99_c11_compat == -1) << 10)
             /* Similarly for warn_c11_c23_compat.  */
             | ((warn_c11_c23_compat == 1) << 11)
             | ((warn_c11_c23_compat == -1) << 12)
             );
  cpp_opts->cpp_pedantic = pedantic = 0;
  warn_pointer_arith = 0;
  cpp_opts->cpp_warn_traditional = warn_traditional = 0;
  flag_iso = 0;
  cpp_opts->cpp_warn_long_long = warn_long_long = 0;
  warn_cxx_compat = 0;
  warn_overlength_strings = 0;
  warn_c90_c99_compat = 0;
  warn_c99_c11_compat = 0;
  warn_c11_c23_compat = 0;
  return ret;
}

/* Restore the warning flags which are controlled by __extension__.
   FLAGS is the return value from disable_extension_diagnostics.  */

static inline void
restore_extension_diagnostics (int flags)
{
  cpp_opts->cpp_pedantic = pedantic = flags & 1;
  warn_pointer_arith = (flags >> 1) & 1;
  cpp_opts->cpp_warn_traditional = warn_traditional = (flags >> 2) & 1;
  flag_iso = (flags >> 3) & 1;
  cpp_opts->cpp_warn_long_long = warn_long_long = (flags >> 4) & 1;
  warn_cxx_compat = (flags >> 5) & 1;
  warn_overlength_strings = (flags >> 6) & 1;
  /* See above for why is this needed.  */
  warn_c90_c99_compat = (flags >> 7) & 1 ? 1 : ((flags >> 8) & 1 ? -1 : 0);
  warn_c99_c11_compat = (flags >> 9) & 1 ? 1 : ((flags >> 10) & 1 ? -1 : 0);
  warn_c11_c23_compat = (flags >> 11) & 1 ? 1 : ((flags >> 12) & 1 ? -1 : 0);
}

/* Helper data structure for parsing #pragma acc routine.  */
struct oacc_routine_data {
  bool error_seen; /* Set if error has been reported.  */
  bool fndecl_seen; /* Set if one fn decl/definition has been seen already.  */
  tree clauses;
  location_t loc;
};

/* Used for parsing objc foreach statements.  */
static tree objc_foreach_break_label, objc_foreach_continue_label;

/* Used for parsing OMP for loops.

   Some notes on flags used for context:
   parser->omp_for_parse_state is non-null anywhere inside the OMP FOR
   construct, except for the final-loop-body.
   The want_nested_loop flag is true if inside a {} sequence where
   a loop-nest (or another {} sequence containing a loop-nest) is expected,
   but has not yet been seen.  It's false when parsing intervening code
   statements or their substatements that cannot contain a loop-nest.
   The in_intervening_code flag is true when parsing any intervening code,
   including substatements, and whether or not want_nested_loop is true.

   And, about error handling:
   The saw_intervening_code flag is set if the loop is not perfectly
   nested, even in the usual case where this is not an error.
   perfect_nesting_fail is set if an error has been diagnosed because an
   imperfectly-nested loop was found where a perfectly-nested one is
   required (we diagnose this only once).
   fail is set if any kind of structural error in the loop nest
   has been found and diagnosed.
  */
struct omp_for_parse_data {
  enum tree_code code;
  tree declv, condv, incrv, initv;
  tree pre_body;
  tree bindings;
  int count;    /* Expected nesting depth.  */
  int depth;    /* Current nesting depth.  */
  location_t for_loc;
  bool ordered : 1;
  bool inscan : 1;
  bool want_nested_loop : 1;
  bool in_intervening_code : 1;
  bool saw_intervening_code: 1;
  bool perfect_nesting_fail : 1;
  bool fail : 1;
};

static bool c_parser_nth_token_starts_std_attributes (c_parser *,
                                                      unsigned int);
static tree c_parser_std_attribute_specifier_sequence (c_parser *);
static void c_parser_external_declaration (c_parser *);
static void c_parser_asm_definition (c_parser *);
static void c_parser_declaration_or_fndef (c_parser *, bool, bool, bool,
                                           bool, bool, tree * = NULL,
                                           vec<c_token> * = NULL,
                                           bool have_attrs = false,
                                           tree attrs = NULL,
                                           struct oacc_routine_data * = NULL,
                                           bool * = NULL);
static bool c_parser_handle_statement_omp_attributes (c_parser *, tree &,
                                                      bool *);
static void c_parser_static_assert_declaration_no_semi (c_parser *);
static void c_parser_static_assert_declaration (c_parser *);
static struct c_typespec c_parser_enum_specifier (c_parser *);
static struct c_typespec c_parser_struct_or_union_specifier (c_parser *);
static tree c_parser_struct_declaration (c_parser *, tree *);
static struct c_typespec c_parser_typeof_specifier (c_parser *);
static tree c_parser_alignas_specifier (c_parser *);
static struct c_declarator *c_parser_direct_declarator (c_parser *, bool,
                                                        c_dtr_syn, bool *);
static struct c_declarator *c_parser_direct_declarator_inner (c_parser *,
                                                              bool,
                                                              struct c_declarator *);
static struct c_arg_info *c_parser_parms_declarator (c_parser *, bool, tree,
                                                     bool);
static struct c_arg_info *c_parser_parms_list_declarator (c_parser *, tree,
                                                          tree, bool);
static struct c_parm *c_parser_parameter_declaration (c_parser *, tree, bool);
static tree c_parser_simple_asm_expr (c_parser *);
static tree c_parser_gnu_attributes (c_parser *);
static struct c_expr c_parser_initializer (c_parser *, tree);
static struct c_expr c_parser_braced_init (c_parser *, tree, bool,
                                           struct obstack *, tree);
static void c_parser_initelt (c_parser *, struct obstack *);
static void c_parser_initval (c_parser *, struct c_expr *,
                              struct obstack *);
static tree c_parser_compound_statement (c_parser *, location_t * = NULL);
static location_t c_parser_compound_statement_nostart (c_parser *);
static void c_parser_label (c_parser *, tree);
static void c_parser_statement (c_parser *, bool *, location_t * = NULL);
static void c_parser_statement_after_labels (c_parser *, bool *,
                                             vec<tree> * = NULL);
static tree c_parser_c99_block_statement (c_parser *, bool *,
                                          location_t * = NULL);
static void c_parser_if_statement (c_parser *, bool *, vec<tree> *);
static void c_parser_switch_statement (c_parser *, bool *);
static void c_parser_while_statement (c_parser *, bool, unsigned short, bool,
                                      bool *);
static void c_parser_do_statement (c_parser *, bool, unsigned short, bool);
static void c_parser_for_statement (c_parser *, bool, unsigned short, bool,
                                    bool *);
static tree c_parser_asm_statement (c_parser *);
static tree c_parser_asm_operands (c_parser *);
static tree c_parser_asm_goto_operands (c_parser *);
static tree c_parser_asm_clobbers (c_parser *);
static struct c_expr c_parser_expr_no_commas (c_parser *, struct c_expr *,
                                              tree = NULL_TREE);
static struct c_expr c_parser_conditional_expression (c_parser *,
                                                      struct c_expr *, tree);
static struct c_expr c_parser_binary_expression (c_parser *, struct c_expr *,
                                                 tree);
static struct c_expr c_parser_cast_expression (c_parser *, struct c_expr *);
static struct c_expr c_parser_unary_expression (c_parser *);
static struct c_expr c_parser_sizeof_expression (c_parser *);
static struct c_expr c_parser_alignof_expression (c_parser *);
static struct c_expr c_parser_postfix_expression (c_parser *);
static struct c_expr c_parser_postfix_expression_after_paren_type (c_parser *,
                                                                   struct c_declspecs *,
                                                                   struct c_type_name *,
                                                                   location_t);
static struct c_expr c_parser_postfix_expression_after_primary (c_parser *,
                                                                location_t loc,
                                                                struct c_expr);
static tree c_parser_transaction (c_parser *, enum rid);
static struct c_expr c_parser_transaction_expression (c_parser *, enum rid);
static tree c_parser_transaction_cancel (c_parser *);
static struct c_expr c_parser_expression (c_parser *);
static struct c_expr c_parser_expression_conv (c_parser *);
static vec<tree, va_gc> *c_parser_expr_list (c_parser *, bool, bool,
                                             vec<tree, va_gc> **, location_t *,
                                             tree *, vec<location_t> *,
                                             unsigned int * = NULL);
static struct c_expr c_parser_has_attribute_expression (c_parser *);

static void c_parser_oacc_declare (c_parser *);
static void c_parser_oacc_enter_exit_data (c_parser *, bool);
static void c_parser_oacc_update (c_parser *);
static void c_parser_omp_construct (c_parser *, bool *);
static void c_parser_omp_threadprivate (c_parser *);
static void c_parser_omp_barrier (c_parser *);
static void c_parser_omp_depobj (c_parser *);
static void c_parser_omp_flush (c_parser *);
static tree c_parser_omp_loop_nest (c_parser *, bool *);
static tree c_parser_omp_for_loop (location_t, c_parser *, enum tree_code,
                                   tree, tree *, bool *);
static void c_parser_omp_taskwait (c_parser *);
static void c_parser_omp_taskyield (c_parser *);
static void c_parser_omp_cancel (c_parser *);
static void c_parser_omp_nothing (c_parser *);

enum pragma_context { pragma_external, pragma_struct, pragma_param,
                      pragma_stmt, pragma_compound };
static bool c_parser_pragma (c_parser *, enum pragma_context, bool *);
static bool c_parser_omp_cancellation_point (c_parser *, enum pragma_context);
static bool c_parser_omp_target (c_parser *, enum pragma_context, bool *);
static void c_parser_omp_begin (c_parser *);
static void c_parser_omp_end (c_parser *);
static bool c_parser_omp_declare (c_parser *, enum pragma_context);
static void c_parser_omp_requires (c_parser *);
static bool c_parser_omp_error (c_parser *, enum pragma_context);
static void c_parser_omp_assumption_clauses (c_parser *, bool);
static void c_parser_omp_allocate (c_parser *);
static void c_parser_omp_assumes (c_parser *);
static bool c_parser_omp_ordered (c_parser *, enum pragma_context, bool *);
static void c_parser_oacc_routine (c_parser *, enum pragma_context);

/* These Objective-C parser functions are only ever called when
   compiling Objective-C.  */
static void c_parser_objc_class_definition (c_parser *, tree);
static void c_parser_objc_class_instance_variables (c_parser *);
static void c_parser_objc_class_declaration (c_parser *);
static void c_parser_objc_alias_declaration (c_parser *);
static void c_parser_objc_protocol_definition (c_parser *, tree);
static bool c_parser_objc_method_type (c_parser *);
static void c_parser_objc_method_definition (c_parser *);
static void c_parser_objc_methodprotolist (c_parser *);
static void c_parser_objc_methodproto (c_parser *);
static tree c_parser_objc_method_decl (c_parser *, bool, tree *, tree *);
static tree c_parser_objc_type_name (c_parser *);
static tree c_parser_objc_protocol_refs (c_parser *);
static void c_parser_objc_try_catch_finally_statement (c_parser *);
static void c_parser_objc_synchronized_statement (c_parser *);
static tree c_parser_objc_selector (c_parser *);
static tree c_parser_objc_selector_arg (c_parser *);
static tree c_parser_objc_receiver (c_parser *);
static tree c_parser_objc_message_args (c_parser *);
static tree c_parser_objc_keywordexpr (c_parser *);
static void c_parser_objc_at_property_declaration (c_parser *);
static void c_parser_objc_at_synthesize_declaration (c_parser *);
static void c_parser_objc_at_dynamic_declaration (c_parser *);
static bool c_parser_objc_diagnose_bad_element_prefix
  (c_parser *, struct c_declspecs *);
static location_t c_parser_parse_rtl_body (c_parser *, char *);

#if ENABLE_ANALYZER

namespace ana {

/* Concrete implementation of ana::translation_unit for the C frontend.  */

class c_translation_unit : public translation_unit
{
public:
  /* Implementation of translation_unit::lookup_constant_by_id for use by the
     analyzer to look up named constants in the user's source code.  */
  tree lookup_constant_by_id (tree id) const final override
  {
    /* Consider decls.  */
    if (tree decl = lookup_name (id))
      if (TREE_CODE (decl) == CONST_DECL)
        if (tree value = DECL_INITIAL (decl))
          if (TREE_CODE (value) == INTEGER_CST)
            return value;

    /* Consider macros.  */
    cpp_hashnode *hashnode = C_CPP_HASHNODE (id);
    if (cpp_macro_p (hashnode))
      if (tree value = consider_macro (hashnode->value.macro))
        return value;

    return NULL_TREE;
  }

  tree
  lookup_type_by_id (tree id) const final override
  {
    if (tree type_decl = lookup_name (id))
        if (TREE_CODE (type_decl) == TYPE_DECL)
          {
            tree record_type = TREE_TYPE (type_decl);
            if (TREE_CODE (record_type) == RECORD_TYPE)
              return record_type;
          }

    return NULL_TREE;
  }

  tree
  lookup_global_var_by_id (tree id) const final override
  {
    if (tree var_decl = lookup_name (id))
      if (TREE_CODE (var_decl) == VAR_DECL)
                                return var_decl;

    return NULL_TREE;
  }

private:
  /* Attempt to get an INTEGER_CST from MACRO.
     Only handle the simplest cases: where MACRO's definition is a single
     token containing a number, by lexing the number again.
     This will handle e.g.
       #define NAME 42
     and other bases but not negative numbers, parentheses or e.g.
       #define NAME 1 << 7
     as doing so would require a parser.  */
  tree consider_macro (cpp_macro *macro) const
  {
    if (macro->paramc > 0)
      return NULL_TREE;
    if (macro->kind != cmk_macro)
      return NULL_TREE;
    if (macro->count != 1)
      return NULL_TREE;
    const cpp_token &tok = macro->exp.tokens[0];
    if (tok.type != CPP_NUMBER)
      return NULL_TREE;

    cpp_reader *old_parse_in = parse_in;
    parse_in = cpp_create_reader (CLK_GNUC89, NULL, line_table);

    pretty_printer pp;
    pp_string (&pp, (const char *) tok.val.str.text);
    pp_newline (&pp);
    cpp_push_buffer (parse_in,
                     (const unsigned char *) pp_formatted_text (&pp),
                     strlen (pp_formatted_text (&pp)),
                     0);

    tree value;
    location_t loc;
    unsigned char cpp_flags;
    c_lex_with_flags (&value, &loc, &cpp_flags, 0);

    cpp_destroy (parse_in);
    parse_in = old_parse_in;

    if (value && TREE_CODE (value) == INTEGER_CST)
      return value;

    return NULL_TREE;
  }
};

} // namespace ana

#endif /* #if ENABLE_ANALYZER */

/* Parse a translation unit (C90 6.7, C99 6.9, C11 6.9).

   translation-unit:
     external-declarations

   external-declarations:
     external-declaration
     external-declarations external-declaration

   GNU extensions:

   translation-unit:
     empty
*/

static void
c_parser_translation_unit (c_parser *parser)
{
  if (c_parser_next_token_is (parser, CPP_EOF))
    {
      pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
               "ISO C forbids an empty translation unit");
    }
  else
    {
      void *obstack_position = obstack_alloc (&parser_obstack, 0);
      mark_valid_location_for_stdc_pragma (false);
      do
        {
          ggc_collect ();
          c_parser_external_declaration (parser);
          obstack_free (&parser_obstack, obstack_position);
        }
      while (c_parser_next_token_is_not (parser, CPP_EOF));
    }

  unsigned int i;
  tree decl;
  FOR_EACH_VEC_ELT (incomplete_record_decls, i, decl)
    if (DECL_SIZE (decl) == NULL_TREE && TREE_TYPE (decl) != error_mark_node)
      error ("storage size of %q+D isn%'t known", decl);

  if (vec_safe_length (current_omp_declare_target_attribute))
    {
      c_omp_declare_target_attr
        a = current_omp_declare_target_attribute->pop ();
      if (!errorcount)
        error ("%qs without corresponding %qs",
               a.device_type >= 0 ? "#pragma omp begin declare target"
                                  : "#pragma omp declare target",
               "#pragma omp end declare target");
      vec_safe_truncate (current_omp_declare_target_attribute, 0);
    }
  if (vec_safe_length (current_omp_begin_assumes))
    {
      if (!errorcount)
        error ("%qs without corresponding %qs",
               "#pragma omp begin assumes", "#pragma omp end assumes");
      vec_safe_truncate (current_omp_begin_assumes, 0);
    }

#if ENABLE_ANALYZER
  if (flag_analyzer)
    {
      ana::c_translation_unit tu;
      ana::on_finish_translation_unit (tu);
    }
#endif
}

/* Parse an external declaration (C90 6.7, C99 6.9, C11 6.9).

   external-declaration:
     function-definition
     declaration

   GNU extensions:

   external-declaration:
     asm-definition
     ;
     __extension__ external-declaration

   Objective-C:

   external-declaration:
     objc-class-definition
     objc-class-declaration
     objc-alias-declaration
     objc-protocol-definition
     objc-method-definition
     @end
*/

static void
c_parser_external_declaration (c_parser *parser)
{
  int ext;
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_KEYWORD:
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_EXTENSION:
          ext = disable_extension_diagnostics ();
          c_parser_consume_token (parser);
          c_parser_external_declaration (parser);
          restore_extension_diagnostics (ext);
          break;
        case RID_ASM:
          c_parser_asm_definition (parser);
          break;
        case RID_AT_INTERFACE:
        case RID_AT_IMPLEMENTATION:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_class_definition (parser, NULL_TREE);
          break;
        case RID_AT_CLASS:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_class_declaration (parser);
          break;
        case RID_AT_ALIAS:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_alias_declaration (parser);
          break;
        case RID_AT_PROTOCOL:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_protocol_definition (parser, NULL_TREE);
          break;
        case RID_AT_PROPERTY:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_at_property_declaration (parser);
          break;
        case RID_AT_SYNTHESIZE:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_at_synthesize_declaration (parser);
          break;
        case RID_AT_DYNAMIC:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_at_dynamic_declaration (parser);
          break;
        case RID_AT_END:
          gcc_assert (c_dialect_objc ());
          c_parser_consume_token (parser);
          objc_finish_implementation ();
          break;
        default:
          goto decl_or_fndef;
        }
      break;
    case CPP_SEMICOLON:
      pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
               "ISO C does not allow extra %<;%> outside of a function");
      c_parser_consume_token (parser);
      break;
    case CPP_PRAGMA:
      mark_valid_location_for_stdc_pragma (true);
      c_parser_pragma (parser, pragma_external, NULL);
      mark_valid_location_for_stdc_pragma (false);
      break;
    case CPP_PLUS:
    case CPP_MINUS:
      if (c_dialect_objc ())
        {
          c_parser_objc_method_definition (parser);
          break;
        }
      /* Else fall through, and yield a syntax error trying to parse
         as a declaration or function definition.  */
      /* FALLTHRU */
    default:
    decl_or_fndef:
      /* A declaration or a function definition (or, in Objective-C,
         an @interface or @protocol with prefix attributes).  We can
         only tell which after parsing the declaration specifiers, if
         any, and the first declarator.  */
      c_parser_declaration_or_fndef (parser, true, true, true, false, true);
      break;
    }
}

static void c_parser_handle_directive_omp_attributes (tree &, vec<c_token> *&,
                                                      vec<c_token> *);
static void c_finish_omp_declare_simd (c_parser *, tree, tree, vec<c_token> *);
static void c_finish_oacc_routine (struct oacc_routine_data *, tree, bool);

/* Build and add a DEBUG_BEGIN_STMT statement with location LOC.  */

static void
add_debug_begin_stmt (location_t loc)
{
  /* Don't add DEBUG_BEGIN_STMTs outside of functions, see PR84721.  */
  if (!MAY_HAVE_DEBUG_MARKER_STMTS || !building_stmt_list_p ())
    return;

  tree stmt = build0 (DEBUG_BEGIN_STMT, void_type_node);
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
}

/* Helper function for c_parser_declaration_or_fndef and
   Handle assume attribute(s).  */

static tree
handle_assume_attribute (location_t here, tree attrs, bool nested)
{
  if (nested)
    for (tree attr = lookup_attribute ("gnu", "assume", attrs); attr;
         attr = lookup_attribute ("gnu", "assume", TREE_CHAIN (attr)))
      {
        tree args = TREE_VALUE (attr);
        int nargs = list_length (args);
        if (nargs != 1)
          {
            error_at (here, "wrong number of arguments specified "
                            "for %qE attribute",
                      get_attribute_name (attr));
            inform (here, "expected %i, found %i", 1, nargs);
          }
        else
          {
            tree arg = TREE_VALUE (args);
            arg = c_objc_common_truthvalue_conversion (here, arg);
            arg = c_fully_fold (arg, false, NULL);
            if (arg != error_mark_node)
              {
                tree fn = build_call_expr_internal_loc (here, IFN_ASSUME,
                                                        void_type_node, 1,
                                                        arg);
                add_stmt (fn);
              }
          }
      }
  else
    pedwarn (here, OPT_Wattributes,
             "%<assume%> attribute at top level");

  return remove_attribute ("gnu", "assume", attrs);
}

/* Parse a declaration or function definition (C90 6.5, 6.7.1, C99
   6.7, 6.9.1, C11 6.7, 6.9.1).  If FNDEF_OK is true, a function definition
   is accepted; otherwise (old-style parameter declarations) only other
   declarations are accepted.  If STATIC_ASSERT_OK is true, a static
   assertion is accepted; otherwise (old-style parameter declarations)
   it is not.  If NESTED is true, we are inside a function or parsing
   old-style parameter declarations; any functions encountered are
   nested functions and declaration specifiers are required; otherwise
   we are at top level and functions are normal functions and
   declaration specifiers may be optional.  If EMPTY_OK is true, empty
   declarations are OK (subject to all other constraints); otherwise
   (old-style parameter declarations) they are diagnosed.  If
   START_ATTR_OK is true, the declaration specifiers may start with
   attributes (GNU or standard); otherwise they may not.
   OBJC_FOREACH_OBJECT_DECLARATION can be used to get back the parsed
   declaration when parsing an Objective-C foreach statement.
   FALLTHRU_ATTR_P is used to signal whether this function parsed
   "__attribute__((fallthrough));".  ATTRS are any standard attributes
   parsed in the caller (in contexts where such attributes had to be
   parsed to determine whether what follows is a declaration or a
   statement); HAVE_ATTRS says whether there were any such attributes
   (even empty).

   declaration:
     declaration-specifiers init-declarator-list[opt] ;
     static_assert-declaration

   function-definition:
     declaration-specifiers[opt] declarator declaration-list[opt]
       compound-statement

   declaration-list:
     declaration
     declaration-list declaration

   init-declarator-list:
     init-declarator
     init-declarator-list , init-declarator

   init-declarator:
     declarator simple-asm-expr[opt] gnu-attributes[opt]
     declarator simple-asm-expr[opt] gnu-attributes[opt] = initializer

   GNU extensions:

   nested-function-definition:
     declaration-specifiers declarator declaration-list[opt]
       compound-statement

   attribute ;

   Objective-C:
     gnu-attributes objc-class-definition
     gnu-attributes objc-category-definition
     gnu-attributes objc-protocol-definition

   The simple-asm-expr and gnu-attributes are GNU extensions.

   This function does not handle __extension__; that is handled in its
   callers.  ??? Following the old parser, __extension__ may start
   external declarations, declarations in functions and declarations
   at the start of "for" loops, but not old-style parameter
   declarations.

   C99 requires declaration specifiers in a function definition; the
   absence is diagnosed through the diagnosis of implicit int.  In GNU
   C we also allow but diagnose declarations without declaration
   specifiers, but only at top level (elsewhere they conflict with
   other syntax).

   In Objective-C, declarations of the looping variable in a foreach
   statement are exceptionally terminated by 'in' (for example, 'for
   (NSObject *object in array) { ... }').

   OpenMP:

   declaration:
     threadprivate-directive

   GIMPLE:

   gimple-function-definition:
     declaration-specifiers[opt] __GIMPLE (gimple-or-rtl-pass-list) declarator
       declaration-list[opt] compound-statement

   rtl-function-definition:
     declaration-specifiers[opt] __RTL (gimple-or-rtl-pass-list) declarator
       declaration-list[opt] compound-statement  */

static void
c_parser_declaration_or_fndef (c_parser *parser, bool fndef_ok,
                               bool static_assert_ok, bool empty_ok,
                               bool nested, bool start_attr_ok,
                               tree *objc_foreach_object_declaration
                               /* = NULL */,
                               vec<c_token> *omp_declare_simd_clauses
                               /* = NULL */,
                               bool have_attrs /* = false */,
                               tree attrs /* = NULL_TREE */,
                               struct oacc_routine_data *oacc_routine_data
                               /* = NULL */,
                               bool *fallthru_attr_p /* = NULL */)
{
  struct c_declspecs *specs;
  tree prefix_attrs;
  tree all_prefix_attrs;
  bool diagnosed_no_specs = false;
  location_t here = c_parser_peek_token (parser)->location;

  add_debug_begin_stmt (c_parser_peek_token (parser)->location);

  if (static_assert_ok
      && c_parser_next_token_is_keyword (parser, RID_STATIC_ASSERT))
    {
      c_parser_static_assert_declaration (parser);
      return;
    }
  specs = build_null_declspecs ();

  /* Handle any standard attributes parsed in the caller.  */
  if (have_attrs)
    {
      declspecs_add_attrs (here, specs, attrs);
      specs->non_std_attrs_seen_p = false;
    }

  /* Try to detect an unknown type name when we have "A B" or "A *B".  */
  if (c_parser_peek_token (parser)->type == CPP_NAME
      && c_parser_peek_token (parser)->id_kind == C_ID_ID
      && (c_parser_peek_2nd_token (parser)->type == CPP_NAME
          || c_parser_peek_2nd_token (parser)->type == CPP_MULT)
      && (!nested || !lookup_name (c_parser_peek_token (parser)->value)))
    {
      tree name = c_parser_peek_token (parser)->value;

      /* Issue a warning about NAME being an unknown type name, perhaps
         with some kind of hint.
         If the user forgot a "struct" etc, suggest inserting
         it.  Otherwise, attempt to look for misspellings.  */
      gcc_rich_location richloc (here);
      if (tag_exists_p (RECORD_TYPE, name))
        {
          /* This is not C++ with its implicit typedef.  */
          richloc.add_fixit_insert_before ("struct ");
          error_at (&richloc,
                    "unknown type name %qE;"
                    " use %<struct%> keyword to refer to the type",
                    name);
        }
      else if (tag_exists_p (UNION_TYPE, name))
        {
          richloc.add_fixit_insert_before ("union ");
          error_at (&richloc,
                    "unknown type name %qE;"
                    " use %<union%> keyword to refer to the type",
                    name);
        }
      else if (tag_exists_p (ENUMERAL_TYPE, name))
        {
          richloc.add_fixit_insert_before ("enum ");
          error_at (&richloc,
                    "unknown type name %qE;"
                    " use %<enum%> keyword to refer to the type",
                    name);
        }
      else
        {
          auto_diagnostic_group d;
          name_hint hint = lookup_name_fuzzy (name, FUZZY_LOOKUP_TYPENAME,
                                              here);
          if (const char *suggestion = hint.suggestion ())
            {
              richloc.add_fixit_replace (suggestion);
              error_at (&richloc,
                        "unknown type name %qE; did you mean %qs?",
                        name, suggestion);
            }
          else
            error_at (here, "unknown type name %qE", name);
        }

      /* Parse declspecs normally to get a correct pointer type, but avoid
         a further "fails to be a type name" error.  Refuse nested functions
         since it is not how the user likely wants us to recover.  */
      c_parser_peek_token (parser)->type = CPP_KEYWORD;
      c_parser_peek_token (parser)->keyword = RID_VOID;
      c_parser_peek_token (parser)->value = error_mark_node;
      fndef_ok = !nested;
    }

  /* When there are standard attributes at the start of the
     declaration (to apply to the entity being declared), an
     init-declarator-list or function definition must be present.  */
  if (c_parser_nth_token_starts_std_attributes (parser, 1))
    have_attrs = true;

  c_parser_declspecs (parser, specs, true, true, start_attr_ok,
                      true, true, start_attr_ok, true, cla_nonabstract_decl);
  if (parser->error)
    {
      c_parser_skip_to_end_of_block_or_statement (parser);
      return;
    }
  if (nested && !specs->declspecs_seen_p)
    {
      c_parser_error (parser, "expected declaration specifiers");
      c_parser_skip_to_end_of_block_or_statement (parser);
      return;
    }

  finish_declspecs (specs);
  bool gnu_auto_type_p = specs->typespec_word == cts_auto_type;
  bool std_auto_type_p = specs->c23_auto_p;
  bool any_auto_type_p = gnu_auto_type_p || std_auto_type_p;
  gcc_assert (!(gnu_auto_type_p && std_auto_type_p));
  const char *auto_type_keyword = gnu_auto_type_p ? "__auto_type" : "auto";
  if (specs->constexpr_p)
    {
      /* An underspecified declaration may not declare tags or members
         or structures or unions; it is undefined behavior to declare
         the members of an enumeration.  Where the structure, union or
         enumeration type is declared within an initializer, this is
         diagnosed elsewhere.  Diagnose here the case of declaring
         such a type in the type specifiers of a constexpr
         declaration.  */
      switch (specs->typespec_kind)
        {
        case ctsk_tagfirstref:
        case ctsk_tagfirstref_attrs:
          error_at (here, "%qT declared in underspecified object declaration",
                    specs->type);
          break;

        case ctsk_tagdef:
          error_at (here, "%qT defined in underspecified object declaration",
                    specs->type);
          break;

        default:
          break;
        }
    }
  if (c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      bool handled_assume = false;
      if (specs->attrs
          && !nested
          && specs->typespec_kind == ctsk_none
          && c_parser_handle_statement_omp_attributes (parser, specs->attrs,
                                                       NULL))
        {
          if (specs->attrs)
            c_warn_unused_attributes (specs->attrs);
          while (parser->in_omp_attribute_pragma)
            {
              gcc_assert (c_parser_next_token_is (parser, CPP_PRAGMA));
              c_parser_pragma (parser, pragma_external, NULL);
            }
          c_parser_consume_token (parser);
          return;
        }
      if (specs->typespec_kind == ctsk_none
          && lookup_attribute ("gnu", "assume", specs->attrs))
        {
          handled_assume = true;
          specs->attrs
            = handle_assume_attribute (here, specs->attrs, nested);
        }
      if (any_auto_type_p)
        error_at (here, "%qs in empty declaration", auto_type_keyword);
      else if (specs->typespec_kind == ctsk_none
               && attribute_fallthrough_p (specs->attrs))
        {
          if (fallthru_attr_p != NULL)
            *fallthru_attr_p = true;
          if (nested)
            {
              tree fn = build_call_expr_internal_loc (here, IFN_FALLTHROUGH,
                                                      void_type_node, 0);
              add_stmt (fn);
            }
          else
            pedwarn (here, OPT_Wattributes,
                     "%<fallthrough%> attribute at top level");
        }
      else if (empty_ok
               && !(have_attrs && specs->non_std_attrs_seen_p)
               && !handled_assume)
        shadow_tag (specs);
      else
        {
          shadow_tag_warned (specs, 1);
          if (!handled_assume)
            pedwarn (here, 0, "empty declaration");
        }
      /* We still have to evaluate size expressions.  */
      if (specs->expr)
        add_stmt (fold_convert (void_type_node, specs->expr));
      c_parser_consume_token (parser);
      if (oacc_routine_data)
        c_finish_oacc_routine (oacc_routine_data, NULL_TREE, false);
      return;
    }

  /* Provide better error recovery.  Note that a type name here is usually
     better diagnosed as a redeclaration.  */
  if (empty_ok
      && specs->typespec_kind == ctsk_tagdef
      && c_parser_next_token_starts_declspecs (parser)
      && !c_parser_next_token_is (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected %<;%>, identifier or %<(%>");
      parser->error = false;
      shadow_tag_warned (specs, 1);
      return;
    }
  else if (c_dialect_objc () && !any_auto_type_p)
    {
      /* Prefix attributes are an error on method decls.  */
      switch (c_parser_peek_token (parser)->type)
        {
          case CPP_PLUS:
          case CPP_MINUS:
            if (c_parser_objc_diagnose_bad_element_prefix (parser, specs))
              return;
            if (specs->attrs)
              {
                warning_at (c_parser_peek_token (parser)->location, 
                            OPT_Wattributes,
                            "prefix attributes are ignored for methods");
                specs->attrs = NULL_TREE;
              }
            if (fndef_ok)
              c_parser_objc_method_definition (parser);
            else
              c_parser_objc_methodproto (parser);
            return;
            break;
          default:
            break;
        }
      /* This is where we parse 'attributes @interface ...',
         'attributes @implementation ...', 'attributes @protocol ...'
         (where attributes could be, for example, __attribute__
         ((deprecated)).
      */
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_AT_INTERFACE:
          {
            if (c_parser_objc_diagnose_bad_element_prefix (parser, specs))
              return;
            c_parser_objc_class_definition (parser, specs->attrs);
            return;
          }
          break;
        case RID_AT_IMPLEMENTATION:
          {
            if (c_parser_objc_diagnose_bad_element_prefix (parser, specs))
              return;
            if (specs->attrs)
              {
                warning_at (c_parser_peek_token (parser)->location, 
                        OPT_Wattributes,
                        "prefix attributes are ignored for implementations");
                specs->attrs = NULL_TREE;
              }
            c_parser_objc_class_definition (parser, NULL_TREE);     
            return;
          }
          break;
        case RID_AT_PROTOCOL:
          {
            if (c_parser_objc_diagnose_bad_element_prefix (parser, specs))
              return;
            c_parser_objc_protocol_definition (parser, specs->attrs);
            return;
          }
          break;
        case RID_AT_ALIAS:
        case RID_AT_CLASS:
        case RID_AT_END:
        case RID_AT_PROPERTY:
          if (specs->attrs)
            {
              c_parser_error (parser, "unexpected attribute");
              specs->attrs = NULL;
            }
          break;
        default:
          break;
        }
    }
  else if (attribute_fallthrough_p (specs->attrs))
    warning_at (here, OPT_Wattributes,
                "%<fallthrough%> attribute not followed by %<;%>");
  else if (lookup_attribute ("gnu", "assume", specs->attrs))
    warning_at (here, OPT_Wattributes,
                "%<assume%> attribute not followed by %<;%>");

  auto_vec<c_token> omp_declare_simd_attr_clauses;
  c_parser_handle_directive_omp_attributes (specs->attrs,
                                            omp_declare_simd_clauses,
                                            &omp_declare_simd_attr_clauses);
  pending_xref_error ();
  prefix_attrs = specs->attrs;
  all_prefix_attrs = prefix_attrs;
  specs->attrs = NULL_TREE;
  while (true)
    {
      struct c_declarator *declarator;
      bool dummy = false;
      timevar_id_t tv;
      tree fnbody = NULL_TREE;
      tree underspec_name = NULL_TREE;
      auto_vec<c_token> omp_dsimd_idattr_clauses;
      /* Declaring either one or more declarators (in which case we
         should diagnose if there were no declaration specifiers) or a
         function definition (in which case the diagnostic for
         implicit int suffices).  */
      declarator = c_parser_declarator (parser, 
                                        specs->typespec_kind != ctsk_none,
                                        C_DTR_NORMAL, &dummy);
      if (declarator == NULL)
        {
          if (omp_declare_simd_clauses)
            c_finish_omp_declare_simd (parser, NULL_TREE, NULL_TREE,
                                       omp_declare_simd_clauses);
          if (oacc_routine_data)
            c_finish_oacc_routine (oacc_routine_data, NULL_TREE, false);
          c_parser_skip_to_end_of_block_or_statement (parser);
          return;
        }
      if (flag_openmp || flag_openmp_simd)
        {
          struct c_declarator *d = declarator;
          while (d->kind != cdk_id)
            d = d->declarator;
          vec<c_token> *dummy = NULL;
          c_parser_handle_directive_omp_attributes (d->u.id.attrs, dummy,
                                                    &omp_dsimd_idattr_clauses);
        }
      if (gnu_auto_type_p && declarator->kind != cdk_id)
        {
          error_at (here,
                    "%<__auto_type%> requires a plain identifier"
                    " as declarator");
          c_parser_skip_to_end_of_block_or_statement (parser);
          return;
        }
      if (std_auto_type_p)
        {
          struct c_declarator *d = declarator;
          while (d->kind == cdk_attrs)
            d = d->declarator;
          if (d->kind != cdk_id)
            {
              error_at (here,
                        "%<auto%> requires a plain identifier, possibly with"
                        " attributes, as declarator");
              c_parser_skip_to_end_of_block_or_statement (parser);
              return;
            }
          underspec_name = d->u.id.id;
        }
      else if (specs->constexpr_p)
        {
          struct c_declarator *d = declarator;
          while (d->kind != cdk_id)
            d = d->declarator;
          underspec_name = d->u.id.id;
        }
      if (c_parser_next_token_is (parser, CPP_EQ)
          || c_parser_next_token_is (parser, CPP_COMMA)
          || c_parser_next_token_is (parser, CPP_SEMICOLON)
          || c_parser_next_token_is_keyword (parser, RID_ASM)
          || c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE)
          || c_parser_next_token_is_keyword (parser, RID_IN))
        {
          tree asm_name = NULL_TREE;
          tree postfix_attrs = NULL_TREE;
          if (!diagnosed_no_specs && !specs->declspecs_seen_p)
            {
              diagnosed_no_specs = true;
              pedwarn (here, 0, "data definition has no type or storage class");
            }
          /* Having seen a data definition, there cannot now be a
             function definition.  */
          fndef_ok = false;
          if (c_parser_next_token_is_keyword (parser, RID_ASM))
            asm_name = c_parser_simple_asm_expr (parser);
          if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
            {
              postfix_attrs = c_parser_gnu_attributes (parser);
              if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
                {
                  /* This means there is an attribute specifier after
                     the declarator in a function definition.  Provide
                     some more information for the user.  */
                  error_at (here, "attributes should be specified before the "
                            "declarator in a function definition");
                  c_parser_skip_to_end_of_block_or_statement (parser);
                  return;
                }
            }
          if (c_parser_next_token_is (parser, CPP_EQ))
            {
              tree d;
              struct c_expr init;
              location_t init_loc;
              c_parser_consume_token (parser);
              if (any_auto_type_p)
                {
                  init_loc = c_parser_peek_token (parser)->location;
                  rich_location richloc (line_table, init_loc);
                  unsigned int underspec_state = 0;
                  if (std_auto_type_p)
                    underspec_state =
                      start_underspecified_init (init_loc, underspec_name);
                  start_init (NULL_TREE, asm_name,
                              (global_bindings_p ()
                               || specs->storage_class == csc_static
                               || specs->constexpr_p),
                              specs->constexpr_p, &richloc);
                  /* A parameter is initialized, which is invalid.  Don't
                     attempt to instrument the initializer.  */
                  int flag_sanitize_save = flag_sanitize;
                  if (nested && !empty_ok)
                    flag_sanitize = 0;
                  init = c_parser_expr_no_commas (parser, NULL);
                  if (std_auto_type_p)
                    finish_underspecified_init (underspec_name,
                                                underspec_state);
                  flag_sanitize = flag_sanitize_save;
                  if (gnu_auto_type_p
                      && TREE_CODE (init.value) == COMPONENT_REF
                      && DECL_C_BIT_FIELD (TREE_OPERAND (init.value, 1)))
                    error_at (here,
                              "%<__auto_type%> used with a bit-field"
                              " initializer");
                  init = convert_lvalue_to_rvalue (init_loc, init, true, true,
                                                   true);
                  tree init_type = TREE_TYPE (init.value);
                  bool vm_type = c_type_variably_modified_p (init_type);
                  if (vm_type)
                    init.value = save_expr (init.value);
                  finish_init ();
                  specs->typespec_kind = ctsk_typeof;
                  specs->locations[cdw_typedef] = init_loc;
                  specs->typedef_p = true;
                  specs->type = init_type;
                  if (specs->postfix_attrs)
                    {
                      /* Postfix [[]] attributes are valid with C23
                         auto, although not with __auto_type, and
                         modify the type given by the initializer.  */
                      specs->postfix_attrs =
                        c_warn_type_attributes (specs->postfix_attrs);
                      decl_attributes (&specs->type, specs->postfix_attrs, 0);
                      specs->postfix_attrs = NULL_TREE;
                    }
                  if (vm_type)
                    {
                      bool maybe_const = true;
                      tree type_expr = c_fully_fold (init.value, false,
                                                     &maybe_const);
                      specs->expr_const_operands &= maybe_const;
                      if (specs->expr)
                        specs->expr = build2 (COMPOUND_EXPR,
                                              TREE_TYPE (type_expr),
                                              specs->expr, type_expr);
                      else
                        specs->expr = type_expr;
                    }
                  d = start_decl (declarator, specs, true,
                                  chainon (postfix_attrs, all_prefix_attrs));
                  if (!d)
                    d = error_mark_node;
                  if (omp_declare_simd_clauses)
                    c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                               omp_declare_simd_clauses);
                  if (!omp_dsimd_idattr_clauses.is_empty ())
                    c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                               &omp_dsimd_idattr_clauses);
                }
              else
                {
                  /* The declaration of the variable is in effect while
                     its initializer is parsed, except for a constexpr
                     variable.  */
                  init_loc = c_parser_peek_token (parser)->location;
                  rich_location richloc (line_table, init_loc);
                  unsigned int underspec_state = 0;
                  if (specs->constexpr_p)
                    underspec_state =
                      start_underspecified_init (init_loc, underspec_name);
                  d = start_decl (declarator, specs, true,
                                  chainon (postfix_attrs,
                                           all_prefix_attrs),
                                  !specs->constexpr_p);
                  if (!d)
                    d = error_mark_node;
                  if (!specs->constexpr_p && omp_declare_simd_clauses)
                    c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                               omp_declare_simd_clauses);
                  if (!specs->constexpr_p
                      && !omp_dsimd_idattr_clauses.is_empty ())
                    c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                               &omp_dsimd_idattr_clauses);
                  start_init (d, asm_name,
                              TREE_STATIC (d) || specs->constexpr_p,
                              specs->constexpr_p, &richloc);
                  /* A parameter is initialized, which is invalid.  Don't
                     attempt to instrument the initializer.  */
                  int flag_sanitize_save = flag_sanitize;
                  if (TREE_CODE (d) == PARM_DECL)
                    flag_sanitize = 0;
                  init = c_parser_initializer (parser, d);
                  flag_sanitize = flag_sanitize_save;
                  if (specs->constexpr_p)
                    {
                      finish_underspecified_init (underspec_name,
                                                  underspec_state);
                      d = pushdecl (d);
                      if (omp_declare_simd_clauses)
                        c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                                   omp_declare_simd_clauses);
                  if (!specs->constexpr_p
                      && !omp_dsimd_idattr_clauses.is_empty ())
                    c_finish_omp_declare_simd (parser, d, NULL_TREE,
                                               &omp_dsimd_idattr_clauses);
                    }
                  finish_init ();
                }
              if (oacc_routine_data)
                c_finish_oacc_routine (oacc_routine_data, d, false);
              if (d != error_mark_node)
                {
                  maybe_warn_string_init (init_loc, TREE_TYPE (d), init);
                  finish_decl (d, init_loc, init.value,
                               init.original_type, asm_name);
                }
            }
          else
            {
              if (any_auto_type_p || specs->constexpr_p)
                {
                  error_at (here,
                            "%qs requires an initialized data declaration",
                            any_auto_type_p ? auto_type_keyword : "constexpr");
                  c_parser_skip_to_end_of_block_or_statement (parser);
                  return;
                }

              location_t lastloc = UNKNOWN_LOCATION;
              tree attrs = chainon (postfix_attrs, all_prefix_attrs);
              tree d = start_decl (declarator, specs, false, attrs, true,
                                   &lastloc);
              if (d && TREE_CODE (d) == FUNCTION_DECL)
                {
                  /* Find the innermost declarator that is neither cdk_id
                     nor cdk_attrs.  */
                  const struct c_declarator *decl = declarator;
                  const struct c_declarator *last_non_id_attrs = NULL;

                  while (decl)
                    switch (decl->kind)
                      {
                      case cdk_array:
                      case cdk_function:
                      case cdk_pointer:
                        last_non_id_attrs = decl;
                        decl = decl->declarator;
                        break;

                      case cdk_attrs:
                        decl = decl->declarator;
                        break;

                      case cdk_id:
                        decl = 0;
                        break;

                      default:
                        gcc_unreachable ();
                      }

                  /* If it exists and is cdk_function declaration whose
                     arguments have not been set yet, use its arguments.  */
                  if (last_non_id_attrs
                      && last_non_id_attrs->kind == cdk_function)
                    {
                      tree parms = last_non_id_attrs->u.arg_info->parms;
                      if (DECL_ARGUMENTS (d) == NULL_TREE
                          && DECL_INITIAL (d) == NULL_TREE)
                        DECL_ARGUMENTS (d) = parms;

                      warn_parm_array_mismatch (lastloc, d, parms);
                    }
                }
              if (omp_declare_simd_clauses
                  || !omp_dsimd_idattr_clauses.is_empty ())
                {
                  tree parms = NULL_TREE;
                  if (d && TREE_CODE (d) == FUNCTION_DECL)
                    {
                      struct c_declarator *ce = declarator;
                      while (ce != NULL)
                        if (ce->kind == cdk_function)
                          {
                            parms = ce->u.arg_info->parms;
                            break;
                          }
                        else
                          ce = ce->declarator;
                    }
                  if (parms)
                    temp_store_parm_decls (d, parms);
                  if (omp_declare_simd_clauses)
                    c_finish_omp_declare_simd (parser, d, parms,
                                               omp_declare_simd_clauses);
                  if (!specs->constexpr_p
                      && !omp_dsimd_idattr_clauses.is_empty ())
                    c_finish_omp_declare_simd (parser, d, parms,
                                               &omp_dsimd_idattr_clauses);
                  if (parms)
                    temp_pop_parm_decls ();
                }
              if (oacc_routine_data)
                c_finish_oacc_routine (oacc_routine_data, d, false);
              if (d)
                finish_decl (d, UNKNOWN_LOCATION, NULL_TREE,
                             NULL_TREE, asm_name);

              if (c_parser_next_token_is_keyword (parser, RID_IN))
                {
                  if (d)
                    *objc_foreach_object_declaration = d;
                  else
                    *objc_foreach_object_declaration = error_mark_node;             
                }
            }
          if (c_parser_next_token_is (parser, CPP_COMMA))
            {
              if (any_auto_type_p || specs->constexpr_p)
                {
                  error_at (here,
                            "%qs may only be used with a single declarator",
                            any_auto_type_p ? auto_type_keyword : "constexpr");
                  c_parser_skip_to_end_of_block_or_statement (parser);
                  return;
                }
              c_parser_consume_token (parser);
              if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
                all_prefix_attrs = chainon (c_parser_gnu_attributes (parser),
                                            prefix_attrs);
              else
                all_prefix_attrs = prefix_attrs;
              continue;
            }
          else if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              c_parser_consume_token (parser);
              return;
            }
          else if (c_parser_next_token_is_keyword (parser, RID_IN))
            {
              /* This can only happen in Objective-C: we found the
                 'in' that terminates the declaration inside an
                 Objective-C foreach statement.  Do not consume the
                 token, so that the caller can use it to determine
                 that this indeed is a foreach context.  */
              return;
            }
          else
            {
              c_parser_error (parser, "expected %<,%> or %<;%>");
              c_parser_skip_to_end_of_block_or_statement (parser);
              return;
            }
        }
      else if (any_auto_type_p || specs->constexpr_p)
        {
          error_at (here,
                    "%qs requires an initialized data declaration",
                    any_auto_type_p ? auto_type_keyword : "constexpr");
          c_parser_skip_to_end_of_block_or_statement (parser);
          return;
        }
      else if (!fndef_ok)
        {
          c_parser_error (parser, "expected %<=%>, %<,%>, %<;%>, "
                          "%<asm%> or %<__attribute__%>");
          c_parser_skip_to_end_of_block_or_statement (parser);
          return;
        }
      /* Function definition (nested or otherwise).  */
      if (nested)
        {
          pedwarn (here, OPT_Wpedantic, "ISO C forbids nested functions");
          c_push_function_context ();
        }
      if (!start_function (specs, declarator, all_prefix_attrs))
        {
          /* At this point we've consumed:
               declaration-specifiers declarator
             and the next token isn't CPP_EQ, CPP_COMMA, CPP_SEMICOLON,
             RID_ASM, RID_ATTRIBUTE, or RID_IN,
             but the
               declaration-specifiers declarator
             aren't grokkable as a function definition, so we have
             an error.  */
          gcc_assert (!c_parser_next_token_is (parser, CPP_SEMICOLON));
          if (c_parser_next_token_starts_declspecs (parser))
            {
              /* If we have
                   declaration-specifiers declarator decl-specs
                 then assume we have a missing semicolon, which would
                 give us:
                   declaration-specifiers declarator  decl-specs
                                                    ^
                                                    ;
                   <~~~~~~~~~ declaration ~~~~~~~~~~>
                 Use c_parser_require to get an error with a fix-it hint.  */
              c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>");
              parser->error = false;
            }
          else
            {
              /* This can appear in many cases looking nothing like a
                 function definition, so we don't give a more specific
                 error suggesting there was one.  */
              c_parser_error (parser, "expected %<=%>, %<,%>, %<;%>, %<asm%> "
                              "or %<__attribute__%>");
            }
          if (nested)
            c_pop_function_context ();
          break;
        }

      if (DECL_DECLARED_INLINE_P (current_function_decl))
        tv = TV_PARSE_INLINE;
      else
        tv = TV_PARSE_FUNC;
      auto_timevar at (g_timer, tv);

      /* Parse old-style parameter declarations.  ??? Attributes are
         not allowed to start declaration specifiers here because of a
         syntax conflict between a function declaration with attribute
         suffix and a function definition with an attribute prefix on
         first old-style parameter declaration.  Following the old
         parser, they are not accepted on subsequent old-style
         parameter declarations either.  However, there is no
         ambiguity after the first declaration, nor indeed on the
         first as long as we don't allow postfix attributes after a
         declarator with a nonempty identifier list in a definition;
         and postfix attributes have never been accepted here in
         function definitions either.  */
      int save_debug_nonbind_markers_p = debug_nonbind_markers_p;
      debug_nonbind_markers_p = 0;
      while (c_parser_next_token_is_not (parser, CPP_EOF)
             && c_parser_next_token_is_not (parser, CPP_OPEN_BRACE))
        c_parser_declaration_or_fndef (parser, false, false, false,
                                       true, false);
      debug_nonbind_markers_p = save_debug_nonbind_markers_p;
      store_parm_decls ();
      if (omp_declare_simd_clauses)
        c_finish_omp_declare_simd (parser, current_function_decl, NULL_TREE,
                                   omp_declare_simd_clauses);
      if (!omp_dsimd_idattr_clauses.is_empty ())
        c_finish_omp_declare_simd (parser, current_function_decl, NULL_TREE,
                                   &omp_dsimd_idattr_clauses);
      if (oacc_routine_data)
        c_finish_oacc_routine (oacc_routine_data, current_function_decl, true);
      location_t startloc = c_parser_peek_token (parser)->location;
      DECL_STRUCT_FUNCTION (current_function_decl)->function_start_locus
        = startloc;
      location_t endloc = startloc;

      /* If the definition was marked with __RTL, use the RTL parser now,
         consuming the function body.  */
      if (specs->declspec_il == cdil_rtl)
        {
          endloc = c_parser_parse_rtl_body (parser, specs->gimple_or_rtl_pass);

          /* Normally, store_parm_decls sets next_is_function_body,
             anticipating a function body.  We need a push_scope/pop_scope
             pair to flush out this state, or subsequent function parsing
             will go wrong.  */
          push_scope ();
          pop_scope ();

          finish_function (endloc);
          return;
        }
      /* If the definition was marked with __GIMPLE then parse the
         function body as GIMPLE.  */
      else if (specs->declspec_il != cdil_none)
        {
          bool saved = in_late_binary_op;
          in_late_binary_op = true;
          c_parser_parse_gimple_body (parser, specs->gimple_or_rtl_pass,
                                      specs->declspec_il,
                                      specs->entry_bb_count);
          in_late_binary_op = saved;
        }
      else
        fnbody = c_parser_compound_statement (parser, &endloc);
      tree fndecl = current_function_decl;
      if (nested)
        {
          tree decl = current_function_decl;
          /* Mark nested functions as needing static-chain initially.
             lower_nested_functions will recompute it but the
             DECL_STATIC_CHAIN flag is also used before that happens,
             by initializer_constant_valid_p.  See gcc.dg/nested-fn-2.c.  */
          DECL_STATIC_CHAIN (decl) = 1;
          add_stmt (fnbody);
          finish_function (endloc);
          c_pop_function_context ();
          add_stmt (build_stmt (DECL_SOURCE_LOCATION (decl), DECL_EXPR, decl));
        }
      else
        {
          if (fnbody)
            add_stmt (fnbody);
          finish_function (endloc);
        }
      /* Get rid of the empty stmt list for GIMPLE/RTL.  */
      if (specs->declspec_il != cdil_none)
        DECL_SAVED_TREE (fndecl) = NULL_TREE;

      break;
    }
}

/* Parse an asm-definition (asm() outside a function body).  This is a
   GNU extension.

   asm-definition:
     simple-asm-expr ;
*/

static void
c_parser_asm_definition (c_parser *parser)
{
  tree asm_str = c_parser_simple_asm_expr (parser);
  if (asm_str)
    symtab->finalize_toplevel_asm (asm_str);
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
}

/* Parse a static assertion (C11 6.7.10).

   static_assert-declaration:
     static_assert-declaration-no-semi ;
*/

static void
c_parser_static_assert_declaration (c_parser *parser)
{
  c_parser_static_assert_declaration_no_semi (parser);
  if (parser->error
      || !c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
    c_parser_skip_to_end_of_block_or_statement (parser);
}

/* Parse a static assertion (C11 6.7.10), without the trailing
   semicolon.

   static_assert-declaration-no-semi:
     _Static_assert ( constant-expression , string-literal )

   C23:
   static_assert-declaration-no-semi:
     _Static_assert ( constant-expression )
*/

static void
c_parser_static_assert_declaration_no_semi (c_parser *parser)
{
  location_t assert_loc, value_loc;
  tree value;
  tree string = NULL_TREE;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_STATIC_ASSERT));
  tree spelling = c_parser_peek_token (parser)->value;
  assert_loc = c_parser_peek_token (parser)->location;
  if (flag_isoc99)
    pedwarn_c99 (assert_loc, OPT_Wpedantic,
                 "ISO C99 does not support %qE", spelling);
  else
    pedwarn_c99 (assert_loc, OPT_Wpedantic,
                 "ISO C90 does not support %qE", spelling);
  c_parser_consume_token (parser);
  matching_parens parens;
  if (!parens.require_open (parser))
    return;
  location_t value_tok_loc = c_parser_peek_token (parser)->location;
  value = convert_lvalue_to_rvalue (value_tok_loc,
                                    c_parser_expr_no_commas (parser, NULL),
                                    true, true).value;
  value_loc = EXPR_LOC_OR_LOC (value, value_tok_loc);
  if (c_parser_next_token_is (parser, CPP_COMMA))
    {
      c_parser_consume_token (parser);
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_STRING:
        case CPP_STRING16:
        case CPP_STRING32:
        case CPP_WSTRING:
        case CPP_UTF8STRING:
          string = c_parser_string_literal (parser, false, true).value;
          break;
        default:
          c_parser_error (parser, "expected string literal");
          return;
        }
    }
  else if (flag_isoc11)
    /* If pedantic for pre-C11, the use of _Static_assert itself will
       have been diagnosed, so do not also diagnose the use of this
       new C23 feature of _Static_assert.  */
    pedwarn_c11 (assert_loc, OPT_Wpedantic,
                 "ISO C11 does not support omitting the string in "
                 "%qE", spelling);
  parens.require_close (parser);

  if (!INTEGRAL_TYPE_P (TREE_TYPE (value)))
    {
      error_at (value_loc, "expression in static assertion is not an integer");
      return;
    }
  if (TREE_CODE (value) != INTEGER_CST)
    {
      value = c_fully_fold (value, false, NULL);
      /* Strip no-op conversions.  */
      STRIP_TYPE_NOPS (value);
      if (TREE_CODE (value) == INTEGER_CST)
        pedwarn (value_loc, OPT_Wpedantic, "expression in static assertion "
                 "is not an integer constant expression");
    }
  if (TREE_CODE (value) != INTEGER_CST)
    {
      error_at (value_loc, "expression in static assertion is not constant");
      return;
    }
  constant_expression_warning (value);
  if (integer_zerop (value))
    {
      if (string)
        error_at (assert_loc, "static assertion failed: %E", string);
      else
        error_at (assert_loc, "static assertion failed");
    }
}

/* Parse some declaration specifiers (possibly none) (C90 6.5, C99
   6.7, C11 6.7), adding them to SPECS (which may already include some).
   Storage class specifiers are accepted iff SCSPEC_OK; type
   specifiers are accepted iff TYPESPEC_OK; alignment specifiers are
   accepted iff ALIGNSPEC_OK; gnu-attributes are accepted at the start
   iff START_ATTR_OK; __auto_type is accepted iff AUTO_TYPE_OK.  In
   addition to the syntax shown, standard attributes are accepted at
   the start iff START_STD_ATTR_OK and at the end iff END_STD_ATTR_OK;
   unlike gnu-attributes, they are not accepted in the middle of the
   list.  (This combines various different syntax productions in the C
   standard, and in some cases gnu-attributes and standard attributes
   at the start may already have been parsed before this function is
   called.)

   declaration-specifiers:
     storage-class-specifier declaration-specifiers[opt]
     type-specifier declaration-specifiers[opt]
     type-qualifier declaration-specifiers[opt]
     function-specifier declaration-specifiers[opt]
     alignment-specifier declaration-specifiers[opt]

   Function specifiers (inline) are from C99, and are currently
   handled as storage class specifiers, as is __thread.  Alignment
   specifiers are from C11.

   C90 6.5.1, C99 6.7.1, C11 6.7.1:
   storage-class-specifier:
     typedef
     extern
     static
     auto
     register
     _Thread_local

   (_Thread_local is new in C11.)

   C99 6.7.4, C11 6.7.4:
   function-specifier:
     inline
     _Noreturn

   (_Noreturn is new in C11.)

   C90 6.5.2, C99 6.7.2, C11 6.7.2:
   type-specifier:
     void
     char
     short
     int
     long
     float
     double
     signed
     unsigned
     _Bool
     _Complex
     [_Imaginary removed in C99 TC2]
     _BitInt ( constant-expression )
     struct-or-union-specifier
     enum-specifier
     typedef-name
     atomic-type-specifier

   (_Bool and _Complex are new in C99.)
   (atomic-type-specifier is new in C11.)
   (_BitInt is new in C23.)

   C90 6.5.3, C99 6.7.3, C11 6.7.3:

   type-qualifier:
     const
     restrict
     volatile
     address-space-qualifier
     _Atomic

   (restrict is new in C99.)
   (_Atomic is new in C11.)

   GNU extensions:

   declaration-specifiers:
     gnu-attributes declaration-specifiers[opt]

   type-qualifier:
     address-space

   address-space:
     identifier recognized by the target

   storage-class-specifier:
     __thread

   type-specifier:
     typeof-specifier
     __auto_type
     __intN
     _Decimal32
     _Decimal64
     _Decimal128
     _Fract
     _Accum
     _Sat

  (_Fract, _Accum, and _Sat are new from ISO/IEC DTR 18037:
   http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1169.pdf)

   atomic-type-specifier
    _Atomic ( type-name )

   Objective-C:

   type-specifier:
     class-name objc-protocol-refs[opt]
     typedef-name objc-protocol-refs
     objc-protocol-refs
*/

void
c_parser_declspecs (c_parser *parser, struct c_declspecs *specs,
                    bool scspec_ok, bool typespec_ok, bool start_attr_ok,
                    bool alignspec_ok, bool auto_type_ok,
                    bool start_std_attr_ok, bool end_std_attr_ok,
                    enum c_lookahead_kind la)
{
  bool attrs_ok = start_attr_ok;
  bool seen_type = specs->typespec_kind != ctsk_none;

  if (!typespec_ok)
    gcc_assert (la == cla_prefer_id);

  if (start_std_attr_ok
      && c_parser_nth_token_starts_std_attributes (parser, 1))
    {
      gcc_assert (!specs->non_std_attrs_seen_p);
      location_t loc = c_parser_peek_token (parser)->location;
      tree attrs = c_parser_std_attribute_specifier_sequence (parser);
      declspecs_add_attrs (loc, specs, attrs);
      specs->non_std_attrs_seen_p = false;
    }

  while (c_parser_next_token_is (parser, CPP_NAME)
         || c_parser_next_token_is (parser, CPP_KEYWORD)
         || (c_dialect_objc () && c_parser_next_token_is (parser, CPP_LESS)))
    {
      struct c_typespec t;
      tree attrs;
      tree align;
      location_t loc = c_parser_peek_token (parser)->location;

      /* If we cannot accept a type, exit if the next token must start
         one.  Also, if we already have seen a tagged definition,
         a typename would be an error anyway and likely the user
         has simply forgotten a semicolon, so we exit.  */
      if ((!typespec_ok || specs->typespec_kind == ctsk_tagdef)
          && c_parser_next_tokens_start_typename (parser, la)
          && !c_parser_next_token_is_qualifier (parser)
          && !c_parser_next_token_is_keyword (parser, RID_ALIGNAS))
        break;

      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          c_token *name_token = c_parser_peek_token (parser);
          tree value = name_token->value;
          c_id_kind kind = name_token->id_kind;

          if (kind == C_ID_ADDRSPACE)
            {
              addr_space_t as
                = name_token->keyword - RID_FIRST_ADDR_SPACE;
              declspecs_add_addrspace (name_token->location, specs, as);
              c_parser_consume_token (parser);
              attrs_ok = true;
              continue;
            }

          gcc_assert (!c_parser_next_token_is_qualifier (parser));

          /* If we cannot accept a type, and the next token must start one,
             exit.  Do the same if we already have seen a tagged definition,
             since it would be an error anyway and likely the user has simply
             forgotten a semicolon.  */
          if (seen_type || !c_parser_next_tokens_start_typename (parser, la))
            break;

          /* Now at an unknown typename (C_ID_ID), a C_ID_TYPENAME or
             a C_ID_CLASSNAME.  */
          c_parser_consume_token (parser);
          seen_type = true;
          attrs_ok = true;
          if (kind == C_ID_ID)
            {
              auto_diagnostic_group d;
              name_hint hint = lookup_name_fuzzy (value, FUZZY_LOOKUP_TYPENAME,
                                                  loc);
              if (const char *suggestion = hint.suggestion ())
                {
                  gcc_rich_location richloc (loc);
                  richloc.add_fixit_replace (suggestion);
                  error_at (&richloc,
                            "unknown type name %qE; did you mean %qs?",
                            value, suggestion);
                }
              else
                error_at (loc, "unknown type name %qE", value);
              t.kind = ctsk_typedef;
              t.spec = error_mark_node;
            }
          else if (kind == C_ID_TYPENAME
                   && (!c_dialect_objc ()
                       || c_parser_next_token_is_not (parser, CPP_LESS)))
            {
              t.kind = ctsk_typedef;
              /* For a typedef name, record the meaning, not the name.
                 In case of 'foo foo, bar;'.  */
              t.spec = lookup_name (value);
            }
          else
            {
              tree proto = NULL_TREE;
              gcc_assert (c_dialect_objc ());
              t.kind = ctsk_objc;
              if (c_parser_next_token_is (parser, CPP_LESS))
                proto = c_parser_objc_protocol_refs (parser);
              t.spec = objc_get_protocol_qualified_type (value, proto);
            }
          t.expr = NULL_TREE;
          t.expr_const_operands = true;
          t.has_enum_type_specifier = false;
          declspecs_add_type (name_token->location, specs, t);
          continue;
        }
      if (c_parser_next_token_is (parser, CPP_LESS))
        {
          /* Make "<SomeProtocol>" equivalent to "id <SomeProtocol>" -
             nisse@lysator.liu.se.  */
          tree proto;
          gcc_assert (c_dialect_objc ());
          if (!typespec_ok || seen_type)
            break;
          proto = c_parser_objc_protocol_refs (parser);
          t.kind = ctsk_objc;
          t.spec = objc_get_protocol_qualified_type (NULL_TREE, proto);
          t.expr = NULL_TREE;
          t.expr_const_operands = true;
          t.has_enum_type_specifier = false;
          declspecs_add_type (loc, specs, t);
          continue;
        }
      gcc_assert (c_parser_next_token_is (parser, CPP_KEYWORD));
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_STATIC:
        case RID_EXTERN:
        case RID_REGISTER:
        case RID_TYPEDEF:
        case RID_INLINE:
        case RID_NORETURN:
        case RID_AUTO:
        case RID_THREAD:
        case RID_CONSTEXPR:
          if (!scspec_ok)
            goto out;
          attrs_ok = true;
          /* TODO: Distinguish between function specifiers (inline, noreturn)
             and storage class specifiers, either here or in
             declspecs_add_scspec.  */
          declspecs_add_scspec (loc, specs,
                                c_parser_peek_token (parser)->value);
          c_parser_consume_token (parser);
          break;
        case RID_AUTO_TYPE:
          if (!auto_type_ok)
            goto out;
          /* Fall through.  */
        case RID_UNSIGNED:
        case RID_LONG:
        case RID_SHORT:
        case RID_SIGNED:
        case RID_COMPLEX:
        case RID_INT:
        case RID_CHAR:
        case RID_FLOAT:
        case RID_DOUBLE:
        case RID_VOID:
        case RID_DFLOAT32:
        case RID_DFLOAT64:
        case RID_DFLOAT128:
        CASE_RID_FLOATN_NX:
        case RID_BOOL:
        case RID_FRACT:
        case RID_ACCUM:
        case RID_SAT:
        case RID_INT_N_0:
        case RID_INT_N_1:
        case RID_INT_N_2:
        case RID_INT_N_3:
          if (!typespec_ok)
            goto out;
          attrs_ok = true;
          seen_type = true;
          if (c_dialect_objc ())
            parser->objc_need_raw_identifier = true;
          t.kind = ctsk_resword;
          t.spec = c_parser_peek_token (parser)->value;
          t.expr = NULL_TREE;
          t.expr_const_operands = true;
          t.has_enum_type_specifier = false;
          declspecs_add_type (loc, specs, t);
          c_parser_consume_token (parser);
          break;
        case RID_ENUM:
          if (!typespec_ok)
            goto out;
          attrs_ok = true;
          seen_type = true;
          t = c_parser_enum_specifier (parser);
          invoke_plugin_callbacks (PLUGIN_FINISH_TYPE, t.spec);
          declspecs_add_type (loc, specs, t);
          break;
        case RID_STRUCT:
        case RID_UNION:
          if (!typespec_ok)
            goto out;
          attrs_ok = true;
          seen_type = true;
          t = c_parser_struct_or_union_specifier (parser);
          invoke_plugin_callbacks (PLUGIN_FINISH_TYPE, t.spec);
          declspecs_add_type (loc, specs, t);
          break;
        case RID_TYPEOF:
        case RID_TYPEOF_UNQUAL:
          /* ??? The old parser rejected typeof after other type
             specifiers, but is a syntax error the best way of
             handling this?  */
          if (!typespec_ok || seen_type)
            goto out;
          attrs_ok = true;
          seen_type = true;
          t = c_parser_typeof_specifier (parser);
          declspecs_add_type (loc, specs, t);
          break;
        case RID_BITINT:
          if (!typespec_ok)
            goto out;
          else
            {
              attrs_ok = true;
              seen_type = true;
              t.kind = ctsk_resword;
              t.spec = c_parser_peek_token (parser)->value;
              t.expr = error_mark_node;
              t.expr_const_operands = true;
              t.has_enum_type_specifier = false;
              c_parser_consume_token (parser);
              matching_parens parens;
              if (parens.require_open (parser))
                {
                  c_expr expr = c_parser_expr_no_commas (parser, NULL);
                  t.expr = convert_lvalue_to_rvalue (loc, expr, true,
                                                     true).value;
                  parens.skip_until_found_close (parser);
                }
              declspecs_add_type (loc, specs, t);
            }
          break;
        case RID_ATOMIC:
          /* C parser handling of Objective-C constructs needs
             checking for correct lvalue-to-rvalue conversions, and
             the code in build_modify_expr handling various
             Objective-C cases, and that in build_unary_op handling
             Objective-C cases for increment / decrement, also needs
             updating; uses of TYPE_MAIN_VARIANT in objc_compare_types
             and objc_types_are_equivalent may also need updates.  */
          if (c_dialect_objc ())
            sorry ("%<_Atomic%> in Objective-C");
          if (flag_isoc99)
            pedwarn_c99 (loc, OPT_Wpedantic,
                         "ISO C99 does not support the %<_Atomic%> qualifier");
          else
            pedwarn_c99 (loc, OPT_Wpedantic,
                         "ISO C90 does not support the %<_Atomic%> qualifier");
          attrs_ok = true;
          tree value;
          value = c_parser_peek_token (parser)->value;
          c_parser_consume_token (parser);
          if (typespec_ok && c_parser_next_token_is (parser, CPP_OPEN_PAREN))
            {
              /* _Atomic ( type-name ).  */
              seen_type = true;
              c_parser_consume_token (parser);
              struct c_type_name *type = c_parser_type_name (parser);
              t.kind = ctsk_typeof;
              t.spec = error_mark_node;
              t.expr = NULL_TREE;
              t.expr_const_operands = true;
              t.has_enum_type_specifier = false;
              if (type != NULL)
                t.spec = groktypename (type, &t.expr,
                                       &t.expr_const_operands);
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                         "expected %<)%>");
              if (t.spec != error_mark_node)
                {
                  if (TREE_CODE (t.spec) == ARRAY_TYPE)
                    error_at (loc, "%<_Atomic%>-qualified array type");
                  else if (TREE_CODE (t.spec) == FUNCTION_TYPE)
                    error_at (loc, "%<_Atomic%>-qualified function type");
                  else if (TYPE_QUALS (t.spec) != TYPE_UNQUALIFIED)
                    error_at (loc, "%<_Atomic%> applied to a qualified type");
                  else
                    t.spec = c_build_qualified_type (t.spec, TYPE_QUAL_ATOMIC);
                }
              declspecs_add_type (loc, specs, t);
            }
          else
            declspecs_add_qual (loc, specs, value);
          break;
        case RID_CONST:
        case RID_VOLATILE:
        case RID_RESTRICT:
          attrs_ok = true;
          declspecs_add_qual (loc, specs, c_parser_peek_token (parser)->value);
          c_parser_consume_token (parser);
          break;
        case RID_ATTRIBUTE:
          if (!attrs_ok)
            goto out;
          attrs = c_parser_gnu_attributes (parser);
          declspecs_add_attrs (loc, specs, attrs);
          break;
        case RID_ALIGNAS:
          if (!alignspec_ok)
            goto out;
          align = c_parser_alignas_specifier (parser);
          declspecs_add_alignas (loc, specs, align);
          break;
        case RID_GIMPLE:
          if (! flag_gimple)
            error_at (loc, "%<__GIMPLE%> only valid with %<-fgimple%>");
          c_parser_consume_token (parser);
          specs->declspec_il = cdil_gimple;
          specs->locations[cdw_gimple] = loc;
          c_parser_gimple_or_rtl_pass_list (parser, specs);
          break;
        case RID_RTL:
          c_parser_consume_token (parser);
          specs->declspec_il = cdil_rtl;
          specs->locations[cdw_rtl] = loc;
          c_parser_gimple_or_rtl_pass_list (parser, specs);
          break;
        default:
          goto out;
        }
    }
 out:
  if (end_std_attr_ok
      && c_parser_nth_token_starts_std_attributes (parser, 1))
    specs->postfix_attrs = c_parser_std_attribute_specifier_sequence (parser);
}

/* Parse an enum specifier (C90 6.5.2.2, C99 6.7.2.2, C11 6.7.2.2).

   enum-specifier:
     enum gnu-attributes[opt] identifier[opt] enum-type-specifier[opt]
       { enumerator-list } gnu-attributes[opt]
     enum gnu-attributes[opt] identifier[opt] enum-type-specifier[opt]
       { enumerator-list , } gnu-attributes[opt] enum-type-specifier[opt]
     enum gnu-attributes[opt] identifier

   The form with trailing comma is new in C99; enum-type-specifiers
   are new in C23.  The forms with gnu-attributes are GNU extensions.
   In GNU C, we accept any expression without commas in the syntax
   (assignment expressions, not just conditional expressions);
   assignment expressions will be diagnosed as non-constant.

   enum-type-specifier:
     : specifier-qualifier-list

   enumerator-list:
     enumerator
     enumerator-list , enumerator

   enumerator:
     enumeration-constant attribute-specifier-sequence[opt]
     enumeration-constant attribute-specifier-sequence[opt]
       = constant-expression

   GNU Extensions:

   enumerator:
     enumeration-constant attribute-specifier-sequence[opt] gnu-attributes[opt]
     enumeration-constant attribute-specifier-sequence[opt] gnu-attributes[opt]
       = constant-expression

*/

static struct c_typespec
c_parser_enum_specifier (c_parser *parser)
{
  struct c_typespec ret;
  bool have_std_attrs;
  bool potential_nesting_p = false;
  tree std_attrs = NULL_TREE;
  tree attrs;
  tree ident = NULL_TREE;
  tree fixed_underlying_type = NULL_TREE;
  location_t enum_loc;
  location_t ident_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_ENUM));
  c_parser_consume_token (parser);
  have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1);
  if (have_std_attrs)
    std_attrs = c_parser_std_attribute_specifier_sequence (parser);
  attrs = c_parser_gnu_attributes (parser);
  enum_loc = c_parser_peek_token (parser)->location;
  /* Set the location in case we create a decl now.  */
  c_parser_set_source_position_from_token (c_parser_peek_token (parser));
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      ident = c_parser_peek_token (parser)->value;
      ident_loc = c_parser_peek_token (parser)->location;
      enum_loc = ident_loc;
      c_parser_consume_token (parser);
    }
  if (c_parser_next_token_is (parser, CPP_COLON)
      /* Distinguish an enum-type-specifier from a bit-field
         declaration of the form "enum e : constant-expression;".  */
      && c_token_starts_typename (c_parser_peek_2nd_token (parser)))
    {
      pedwarn_c11 (enum_loc, OPT_Wpedantic,
                   "ISO C does not support specifying %<enum%> underlying "
                   "types before C23");
      if (ident)
        {
          /* The tag is in scope during the enum-type-specifier (which
             may refer to the tag inside typeof).  */
          ret = parser_xref_tag (ident_loc, ENUMERAL_TYPE, ident,
                                 have_std_attrs, std_attrs, true);
          if (!ENUM_FIXED_UNDERLYING_TYPE_P (ret.spec))
            error_at (enum_loc, "%<enum%> declared both with and without "
                      "fixed underlying type");
          potential_nesting_p = NULL_TREE == TYPE_VALUES (ret.spec);
        }
      else
        {
          /* There must be an enum definition, so this initialization
             (to avoid possible warnings about uninitialized data)
             will be replaced later (either with the results of that
             definition, or with the results of error handling for the
             case of no tag and no definition).  */
          ret.spec = NULL_TREE;
          ret.kind = ctsk_tagdef;
          ret.expr = NULL_TREE;
          ret.expr_const_operands = true;
          ret.has_enum_type_specifier = true;
        }
      c_parser_consume_token (parser);
      struct c_declspecs *specs = build_null_declspecs ();
      c_parser_declspecs (parser, specs, false, true, false, false, false,
                          false, true, cla_prefer_id);
      finish_declspecs (specs);
      if (specs->default_int_p)
        error_at (enum_loc, "no %<enum%> underlying type specified");
      else if (TREE_CODE (specs->type) != INTEGER_TYPE
               && TREE_CODE (specs->type) != BOOLEAN_TYPE)
        {
          error_at (enum_loc, "invalid %<enum%> underlying type");
          specs->type = integer_type_node;
        }
      else if (specs->restrict_p)
        error_at (enum_loc, "invalid use of %<restrict%>");
      fixed_underlying_type = TYPE_MAIN_VARIANT (specs->type);
      if (ident)
        {
          /* The type specified must be consistent with any previously
             specified underlying type.  If this is a newly declared
             type, it is now a complete type.  */
          if (ENUM_FIXED_UNDERLYING_TYPE_P (ret.spec)
              && ENUM_UNDERLYING_TYPE (ret.spec) == NULL_TREE)
            {
              TYPE_MIN_VALUE (ret.spec) =
                TYPE_MIN_VALUE (fixed_underlying_type);
              TYPE_MAX_VALUE (ret.spec) =
                TYPE_MAX_VALUE (fixed_underlying_type);
              TYPE_UNSIGNED (ret.spec) = TYPE_UNSIGNED (fixed_underlying_type);
              SET_TYPE_ALIGN (ret.spec, TYPE_ALIGN (fixed_underlying_type));
              TYPE_SIZE (ret.spec) = NULL_TREE;
              TYPE_PRECISION (ret.spec) =
                TYPE_PRECISION (fixed_underlying_type);
              ENUM_UNDERLYING_TYPE (ret.spec) = fixed_underlying_type;
              layout_type (ret.spec);
            }
          else if (ENUM_FIXED_UNDERLYING_TYPE_P (ret.spec)
                   && !comptypes (fixed_underlying_type,
                                  ENUM_UNDERLYING_TYPE (ret.spec)))
            {
              error_at (enum_loc, "%<enum%> underlying type incompatible with "
                        "previous declaration");
              fixed_underlying_type = ENUM_UNDERLYING_TYPE (ret.spec);
            }
        }
    }
  if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    {
      /* Parse an enum definition.  */
      struct c_enum_contents the_enum;
      tree type;
      tree postfix_attrs;
      /* We chain the enumerators in reverse order, then put them in
         forward order at the end.  */
      tree values;
      timevar_push (TV_PARSE_ENUM);
      type = start_enum (enum_loc, &the_enum, ident, fixed_underlying_type,
                         potential_nesting_p);
      values = NULL_TREE;
      c_parser_consume_token (parser);
      while (true)
        {
          tree enum_id;
          tree enum_value;
          tree enum_decl;
          bool seen_comma;
          c_token *token;
          location_t comma_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
          location_t decl_loc, value_loc;
          if (c_parser_next_token_is_not (parser, CPP_NAME))
            {
              /* Give a nicer error for "enum {}".  */
              if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE)
                  && !parser->error)
                {
                  error_at (c_parser_peek_token (parser)->location,
                            "empty enum is invalid");
                  parser->error = true;
                }
              else
                c_parser_error (parser, "expected identifier");
              c_parser_skip_until_found (parser, CPP_CLOSE_BRACE, NULL);
              values = error_mark_node;
              break;
            }
          token = c_parser_peek_token (parser);
          enum_id = token->value;
          /* Set the location in case we create a decl now.  */
          c_parser_set_source_position_from_token (token);
          decl_loc = value_loc = token->location;
          c_parser_consume_token (parser);
          /* Parse any specified attributes.  */
          tree std_attrs = NULL_TREE;
          if (c_parser_nth_token_starts_std_attributes (parser, 1))
            std_attrs = c_parser_std_attribute_specifier_sequence (parser);
          tree enum_attrs = chainon (std_attrs,
                                     c_parser_gnu_attributes (parser));
          if (c_parser_next_token_is (parser, CPP_EQ))
            {
              c_parser_consume_token (parser);
              value_loc = c_parser_peek_token (parser)->location;
              enum_value = convert_lvalue_to_rvalue (value_loc,
                                                     (c_parser_expr_no_commas
                                                      (parser, NULL)),
                                                     true, true).value;
            }
          else
            enum_value = NULL_TREE;
          enum_decl = build_enumerator (decl_loc, value_loc,
                                        &the_enum, enum_id, enum_value);
          if (enum_attrs)
            decl_attributes (&TREE_PURPOSE (enum_decl), enum_attrs, 0);
          TREE_CHAIN (enum_decl) = values;
          values = enum_decl;
          seen_comma = false;
          if (c_parser_next_token_is (parser, CPP_COMMA))
            {
              comma_loc = c_parser_peek_token (parser)->location;
              seen_comma = true;
              c_parser_consume_token (parser);
            }
          if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
            {
              if (seen_comma)
                pedwarn_c90 (comma_loc, OPT_Wpedantic,
                             "comma at end of enumerator list");
              c_parser_consume_token (parser);
              break;
            }
          if (!seen_comma)
            {
              c_parser_error (parser, "expected %<,%> or %<}%>");
              c_parser_skip_until_found (parser, CPP_CLOSE_BRACE, NULL);
              values = error_mark_node;
              break;
            }
        }
      postfix_attrs = c_parser_gnu_attributes (parser);
      ret.spec = finish_enum (type, nreverse (values),
                              chainon (std_attrs,
                                       chainon (attrs, postfix_attrs)));
      ret.kind = ctsk_tagdef;
      ret.expr = NULL_TREE;
      ret.expr_const_operands = true;
      ret.has_enum_type_specifier = fixed_underlying_type != NULL_TREE;
      timevar_pop (TV_PARSE_ENUM);
      return ret;
    }
  else if (!ident)
    {
      c_parser_error (parser, "expected %<{%>");
      ret.spec = error_mark_node;
      ret.kind = ctsk_tagref;
      ret.expr = NULL_TREE;
      ret.expr_const_operands = true;
      ret.has_enum_type_specifier = false;
      return ret;
    }
  /* Attributes may only appear when the members are defined or in
     certain forward declarations (treat enum forward declarations in
     GNU C analogously to struct and union forward declarations in
     standard C).  */
  if (have_std_attrs && c_parser_next_token_is_not (parser, CPP_SEMICOLON))
    c_parser_error (parser, "expected %<;%>");
  if (fixed_underlying_type == NULL_TREE)
    {
      ret = parser_xref_tag (ident_loc, ENUMERAL_TYPE, ident, have_std_attrs,
                             std_attrs, false);
      /* In ISO C, enumerated types without a fixed underlying type
         can be referred to only if already defined.  */
      if (pedantic && !COMPLETE_TYPE_P (ret.spec))
        {
          gcc_assert (ident);
          pedwarn (enum_loc, OPT_Wpedantic,
                   "ISO C forbids forward references to %<enum%> types");
        }
    }
  return ret;
}

/* Parse a struct or union specifier (C90 6.5.2.1, C99 6.7.2.1, C11 6.7.2.1).

   struct-or-union-specifier:
     struct-or-union attribute-specifier-sequence[opt] gnu-attributes[opt]
       identifier[opt] { struct-contents } gnu-attributes[opt]
     struct-or-union attribute-specifier-sequence[opt] gnu-attributes[opt]
       identifier

   struct-contents:
     struct-declaration-list

   struct-declaration-list:
     struct-declaration ;
     struct-declaration-list struct-declaration ;

   GNU extensions:

   struct-contents:
     empty
     struct-declaration
     struct-declaration-list struct-declaration

   struct-declaration-list:
     struct-declaration-list ;
     ;

   (Note that in the syntax here, unlike that in ISO C, the semicolons
   are included here rather than in struct-declaration, in order to
   describe the syntax with extra semicolons and missing semicolon at
   end.)

   Objective-C:

   struct-declaration-list:
     @defs ( class-name )

   (Note this does not include a trailing semicolon, but can be
   followed by further declarations, and gets a pedwarn-if-pedantic
   when followed by a semicolon.)  */

static struct c_typespec
c_parser_struct_or_union_specifier (c_parser *parser)
{
  struct c_typespec ret;
  bool have_std_attrs;
  tree std_attrs = NULL_TREE;
  tree attrs;
  tree ident = NULL_TREE;
  location_t struct_loc;
  location_t ident_loc = UNKNOWN_LOCATION;
  enum tree_code code;
  switch (c_parser_peek_token (parser)->keyword)
    {
    case RID_STRUCT:
      code = RECORD_TYPE;
      break;
    case RID_UNION:
      code = UNION_TYPE;
      break;
    default:
      gcc_unreachable ();
    }
  struct_loc = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);
  have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1);
  if (have_std_attrs)
    std_attrs = c_parser_std_attribute_specifier_sequence (parser);
  attrs = c_parser_gnu_attributes (parser);

  /* Set the location in case we create a decl now.  */
  c_parser_set_source_position_from_token (c_parser_peek_token (parser));

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      ident = c_parser_peek_token (parser)->value;
      ident_loc = c_parser_peek_token (parser)->location;
      struct_loc = ident_loc;
      c_parser_consume_token (parser);
    }
  if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    {
      /* Parse a struct or union definition.  Start the scope of the
         tag before parsing components.  */
      class c_struct_parse_info *struct_info;
      tree type = start_struct (struct_loc, code, ident, &struct_info);
      tree postfix_attrs;
      /* We chain the components in reverse order, then put them in
         forward order at the end.  Each struct-declaration may
         declare multiple components (comma-separated), so we must use
         chainon to join them, although when parsing each
         struct-declaration we can use TREE_CHAIN directly.

         The theory behind all this is that there will be more
         semicolon separated fields than comma separated fields, and
         so we'll be minimizing the number of node traversals required
         by chainon.  */
      tree contents;
      tree expr = NULL;
      timevar_push (TV_PARSE_STRUCT);
      contents = NULL_TREE;
      c_parser_consume_token (parser);
      /* Handle the Objective-C @defs construct,
         e.g. foo(sizeof(struct{ @defs(ClassName) }));.  */
      if (c_parser_next_token_is_keyword (parser, RID_AT_DEFS))
        {
          tree name;
          gcc_assert (c_dialect_objc ());
          c_parser_consume_token (parser);
          matching_parens parens;
          if (!parens.require_open (parser))
            goto end_at_defs;
          if (c_parser_next_token_is (parser, CPP_NAME)
              && c_parser_peek_token (parser)->id_kind == C_ID_CLASSNAME)
            {
              name = c_parser_peek_token (parser)->value;
              c_parser_consume_token (parser);
            }
          else
            {
              c_parser_error (parser, "expected class name");
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
              goto end_at_defs;
            }
          parens.skip_until_found_close (parser);
          contents = nreverse (objc_get_class_ivars (name));
        }
    end_at_defs:
      /* Parse the struct-declarations and semicolons.  Problems with
         semicolons are diagnosed here; empty structures are diagnosed
         elsewhere.  */
      while (true)
        {
          tree decls;
          /* Parse any stray semicolon.  */
          if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              location_t semicolon_loc
                = c_parser_peek_token (parser)->location;
              gcc_rich_location richloc (semicolon_loc);
              richloc.add_fixit_remove ();
              pedwarn (&richloc, OPT_Wpedantic,
                       "extra semicolon in struct or union specified");
              c_parser_consume_token (parser);
              continue;
            }
          /* Stop if at the end of the struct or union contents.  */
          if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
            {
              c_parser_consume_token (parser);
              break;
            }
          /* Accept #pragmas at struct scope.  */
          if (c_parser_next_token_is (parser, CPP_PRAGMA))
            {
              c_parser_pragma (parser, pragma_struct, NULL);
              continue;
            }
          /* Parse some comma-separated declarations, but not the
             trailing semicolon if any.  */
          decls = c_parser_struct_declaration (parser, &expr);
          contents = chainon (decls, contents);
          /* If no semicolon follows, either we have a parse error or
             are at the end of the struct or union and should
             pedwarn.  */
          if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            c_parser_consume_token (parser);
          else
            {
              if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
                pedwarn (c_parser_peek_token (parser)->location, 0,
                         "no semicolon at end of struct or union");
              else if (parser->error
                       || !c_parser_next_token_starts_declspecs (parser))
                {
                  c_parser_error (parser, "expected %<;%>");
                  c_parser_skip_until_found (parser, CPP_CLOSE_BRACE, NULL);
                  break;
                }

              /* If we come here, we have already emitted an error
                 for an expected `;', identifier or `(', and we also
                 recovered already.  Go on with the next field. */
            }
        }
      postfix_attrs = c_parser_gnu_attributes (parser);
      ret.spec = finish_struct (struct_loc, type, nreverse (contents),
                                chainon (std_attrs,
                                         chainon (attrs, postfix_attrs)),
                                struct_info, &expr);
      ret.kind = ctsk_tagdef;
      ret.expr = expr;
      ret.expr_const_operands = true;
      ret.has_enum_type_specifier = false;
      timevar_pop (TV_PARSE_STRUCT);
      return ret;
    }
  else if (!ident)
    {
      c_parser_error (parser, "expected %<{%>");
      ret.spec = error_mark_node;
      ret.kind = ctsk_tagref;
      ret.expr = NULL_TREE;
      ret.expr_const_operands = true;
      ret.has_enum_type_specifier = false;
      return ret;
    }
  /* Attributes may only appear when the members are defined or in
     certain forward declarations.  */
  if (have_std_attrs && c_parser_next_token_is_not (parser, CPP_SEMICOLON))
    c_parser_error (parser, "expected %<;%>");
  /* ??? Existing practice is that GNU attributes are ignored after
     the struct or union keyword when not defining the members.  */
  ret = parser_xref_tag (ident_loc, code, ident, have_std_attrs, std_attrs,
                         false);
  return ret;
}

/* Parse a struct-declaration (C90 6.5.2.1, C99 6.7.2.1, C11 6.7.2.1),
   *without* the trailing semicolon.

   struct-declaration:
     attribute-specifier-sequence[opt] specifier-qualifier-list
       attribute-specifier-sequence[opt] struct-declarator-list
     static_assert-declaration-no-semi

   specifier-qualifier-list:
     type-specifier specifier-qualifier-list[opt]
     type-qualifier specifier-qualifier-list[opt]
     alignment-specifier specifier-qualifier-list[opt]
     gnu-attributes specifier-qualifier-list[opt]

   struct-declarator-list:
     struct-declarator
     struct-declarator-list , gnu-attributes[opt] struct-declarator

   struct-declarator:
     declarator gnu-attributes[opt]
     declarator[opt] : constant-expression gnu-attributes[opt]

   GNU extensions:

   struct-declaration:
     __extension__ struct-declaration
     specifier-qualifier-list

   Unlike the ISO C syntax, semicolons are handled elsewhere.  The use
   of gnu-attributes where shown is a GNU extension.  In GNU C, we accept
   any expression without commas in the syntax (assignment
   expressions, not just conditional expressions); assignment
   expressions will be diagnosed as non-constant.  */

static tree
c_parser_struct_declaration (c_parser *parser, tree *expr)
{
  struct c_declspecs *specs;
  tree prefix_attrs;
  tree all_prefix_attrs;
  tree decls;
  location_t decl_loc;
  if (c_parser_next_token_is_keyword (parser, RID_EXTENSION))
    {
      int ext;
      tree decl;
      ext = disable_extension_diagnostics ();
      c_parser_consume_token (parser);
      decl = c_parser_struct_declaration (parser, expr);
      restore_extension_diagnostics (ext);
      return decl;
    }
  if (c_parser_next_token_is_keyword (parser, RID_STATIC_ASSERT))
    {
      c_parser_static_assert_declaration_no_semi (parser);
      return NULL_TREE;
    }
  specs = build_null_declspecs ();
  decl_loc = c_parser_peek_token (parser)->location;
  /* Strictly by the standard, we shouldn't allow _Alignas here,
     but it appears to have been intended to allow it there, so
     we're keeping it as it is until WG14 reaches a conclusion
     of N1731.
     <http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1731.pdf>  */
  c_parser_declspecs (parser, specs, false, true, true,
                      true, false, true, true, cla_nonabstract_decl);
  if (parser->error)
    return NULL_TREE;
  if (!specs->declspecs_seen_p)
    {
      c_parser_error (parser, "expected specifier-qualifier-list");
      return NULL_TREE;
    }
  finish_declspecs (specs);
  if (c_parser_next_token_is (parser, CPP_SEMICOLON)
      || c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
    {
      tree ret;
      if (specs->typespec_kind == ctsk_none)
        {
          pedwarn (decl_loc, OPT_Wpedantic,
                   "ISO C forbids member declarations with no members");
          shadow_tag_warned (specs, pedantic);
          ret = NULL_TREE;
        }
      else
        {
          /* Support for unnamed structs or unions as members of
             structs or unions (which is [a] useful and [b] supports
             MS P-SDK).  */
          tree attrs = NULL;

          ret = grokfield (c_parser_peek_token (parser)->location,
                           build_id_declarator (NULL_TREE), specs,
                           NULL_TREE, &attrs, expr);
          if (ret)
            decl_attributes (&ret, attrs, 0);
        }
      return ret;
    }

  /* Provide better error recovery.  Note that a type name here is valid,
     and will be treated as a field name.  */
  if (specs->typespec_kind == ctsk_tagdef
      && TREE_CODE (specs->type) != ENUMERAL_TYPE
      && c_parser_next_token_starts_declspecs (parser)
      && !c_parser_next_token_is (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected %<;%>, identifier or %<(%>");
      parser->error = false;
      return NULL_TREE;
    }

  pending_xref_error ();
  prefix_attrs = specs->attrs;
  all_prefix_attrs = prefix_attrs;
  specs->attrs = NULL_TREE;
  decls = NULL_TREE;
  while (true)
    {
      /* Declaring one or more declarators or un-named bit-fields.  */
      struct c_declarator *declarator;
      bool dummy = false;
      if (c_parser_next_token_is (parser, CPP_COLON))
        declarator = build_id_declarator (NULL_TREE);
      else
        declarator = c_parser_declarator (parser,
                                          specs->typespec_kind != ctsk_none,
                                          C_DTR_NORMAL, &dummy);
      if (declarator == NULL)
        {
          c_parser_skip_to_end_of_block_or_statement (parser);
          break;
        }
      if (c_parser_next_token_is (parser, CPP_COLON)
          || c_parser_next_token_is (parser, CPP_COMMA)
          || c_parser_next_token_is (parser, CPP_SEMICOLON)
          || c_parser_next_token_is (parser, CPP_CLOSE_BRACE)
          || c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
        {
          tree postfix_attrs = NULL_TREE;
          tree width = NULL_TREE;
          tree d;
          if (c_parser_next_token_is (parser, CPP_COLON))
            {
              c_parser_consume_token (parser);
              location_t loc = c_parser_peek_token (parser)->location;
              width = convert_lvalue_to_rvalue (loc,
                                                (c_parser_expr_no_commas
                                                 (parser, NULL)),
                                                true, true).value;
            }
          if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
            postfix_attrs = c_parser_gnu_attributes (parser);
          d = grokfield (c_parser_peek_token (parser)->location,
                         declarator, specs, width, &all_prefix_attrs, expr);
          decl_attributes (&d, chainon (postfix_attrs,
                                        all_prefix_attrs), 0);
          DECL_CHAIN (d) = decls;
          decls = d;
          if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
            all_prefix_attrs = chainon (c_parser_gnu_attributes (parser),
                                        prefix_attrs);
          else
            all_prefix_attrs = prefix_attrs;
          if (c_parser_next_token_is (parser, CPP_COMMA))
            c_parser_consume_token (parser);
          else if (c_parser_next_token_is (parser, CPP_SEMICOLON)
                   || c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
            {
              /* Semicolon consumed in caller.  */
              break;
            }
          else
            {
              c_parser_error (parser, "expected %<,%>, %<;%> or %<}%>");
              break;
            }
        }
      else
        {
          c_parser_error (parser,
                          "expected %<:%>, %<,%>, %<;%>, %<}%> or "
                          "%<__attribute__%>");
          break;
        }
    }
  return decls;
}

/* Parse a typeof specifier (a GNU extension adopted in C23).

   typeof-specifier:
     typeof ( expression )
     typeof ( type-name )
     typeof_unqual ( expression )
     typeof_unqual ( type-name )
*/

static struct c_typespec
c_parser_typeof_specifier (c_parser *parser)
{
  bool is_unqual;
  bool is_std;
  struct c_typespec ret;
  ret.kind = ctsk_typeof;
  ret.spec = error_mark_node;
  ret.expr = NULL_TREE;
  ret.expr_const_operands = true;
  ret.has_enum_type_specifier = false;
  if (c_parser_next_token_is_keyword (parser, RID_TYPEOF))
    {
      is_unqual = false;
      tree spelling = c_parser_peek_token (parser)->value;
      is_std = (flag_isoc23
                && strcmp (IDENTIFIER_POINTER (spelling), "typeof") == 0);
    }
  else
    {
      gcc_assert (c_parser_next_token_is_keyword (parser, RID_TYPEOF_UNQUAL));
      is_unqual = true;
      tree spelling = c_parser_peek_token (parser)->value;
      is_std = strcmp (IDENTIFIER_POINTER (spelling), "typeof_unqual") == 0;
    }
  c_parser_consume_token (parser);
  c_inhibit_evaluation_warnings++;
  in_typeof++;
  matching_parens parens;
  if (!parens.require_open (parser))
    {
      c_inhibit_evaluation_warnings--;
      in_typeof--;
      return ret;
    }
  if (c_parser_next_tokens_start_typename (parser, cla_prefer_id))
    {
      struct c_type_name *type = c_parser_type_name (parser);
      c_inhibit_evaluation_warnings--;
      in_typeof--;
      if (type != NULL)
        {
          ret.spec = groktypename (type, &ret.expr, &ret.expr_const_operands);
          pop_maybe_used (c_type_variably_modified_p (ret.spec));
        }
    }
  else
    {
      bool was_vm;
      location_t here = c_parser_peek_token (parser)->location;
      struct c_expr expr = c_parser_expression (parser);
      c_inhibit_evaluation_warnings--;
      in_typeof--;
      if (TREE_CODE (expr.value) == COMPONENT_REF
          && DECL_C_BIT_FIELD (TREE_OPERAND (expr.value, 1)))
        error_at (here, "%<typeof%> applied to a bit-field");
      mark_exp_read (expr.value);
      ret.spec = TREE_TYPE (expr.value);
      was_vm = c_type_variably_modified_p (ret.spec);
      /* This is returned with the type so that when the type is
         evaluated, this can be evaluated.  */
      if (was_vm)
        ret.expr = c_fully_fold (expr.value, false, &ret.expr_const_operands);
      pop_maybe_used (was_vm);
    }
  parens.skip_until_found_close (parser);
  if (ret.spec != error_mark_node)
    {
      if (is_unqual && TYPE_QUALS (ret.spec) != TYPE_UNQUALIFIED)
        ret.spec = TYPE_MAIN_VARIANT (ret.spec);
      if (is_std)
        {
          /* In ISO C terms, _Noreturn is not part of the type of
             expressions such as &abort, but in GCC it is represented
             internally as a type qualifier.  */
          if (TREE_CODE (ret.spec) == FUNCTION_TYPE
              && TYPE_QUALS (ret.spec) != TYPE_UNQUALIFIED)
            ret.spec = TYPE_MAIN_VARIANT (ret.spec);
          else if (FUNCTION_POINTER_TYPE_P (ret.spec)
                   && TYPE_QUALS (TREE_TYPE (ret.spec)) != TYPE_UNQUALIFIED)
            ret.spec
              = build_pointer_type (TYPE_MAIN_VARIANT (TREE_TYPE (ret.spec)));
        }
    }
  return ret;
}

/* Parse an alignment-specifier.

   C11 6.7.5:

   alignment-specifier:
     _Alignas ( type-name )
     _Alignas ( constant-expression )
*/

static tree
c_parser_alignas_specifier (c_parser * parser)
{
  tree ret = error_mark_node;
  location_t loc = c_parser_peek_token (parser)->location;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_ALIGNAS));
  tree spelling = c_parser_peek_token (parser)->value;
  c_parser_consume_token (parser);
  if (flag_isoc99)
    pedwarn_c99 (loc, OPT_Wpedantic,
                 "ISO C99 does not support %qE", spelling);
  else
    pedwarn_c99 (loc, OPT_Wpedantic,
                 "ISO C90 does not support %qE", spelling);
  matching_parens parens;
  if (!parens.require_open (parser))
    return ret;
  if (c_parser_next_tokens_start_typename (parser, cla_prefer_id))
    {
      struct c_type_name *type = c_parser_type_name (parser);
      if (type != NULL)
        ret = c_sizeof_or_alignof_type (loc, groktypename (type, NULL, NULL),
                                        false, true, 1);
    }
  else
    ret = convert_lvalue_to_rvalue (loc,
                                    c_parser_expr_no_commas (parser, NULL),
                                    true, true).value;
  parens.skip_until_found_close (parser);
  return ret;
}

/* Parse a declarator, possibly an abstract declarator (C90 6.5.4,
   6.5.5, C99 6.7.5, 6.7.6, C11 6.7.6, 6.7.7).  If TYPE_SEEN_P then
   a typedef name may be redeclared; otherwise it may not.  KIND
   indicates which kind of declarator is wanted.  Returns a valid
   declarator except in the case of a syntax error in which case NULL is
   returned.  *SEEN_ID is set to true if an identifier being declared is
   seen; this is used to diagnose bad forms of abstract array declarators
   and to determine whether an identifier list is syntactically permitted.

   declarator:
     pointer[opt] direct-declarator

   direct-declarator:
     identifier
     ( gnu-attributes[opt] declarator )
     direct-declarator array-declarator
     direct-declarator ( parameter-type-list )
     direct-declarator ( identifier-list[opt] )

   pointer:
     * type-qualifier-list[opt]
     * type-qualifier-list[opt] pointer

   type-qualifier-list:
     type-qualifier
     gnu-attributes
     type-qualifier-list type-qualifier
     type-qualifier-list gnu-attributes

   array-declarator:
     [ type-qualifier-list[opt] assignment-expression[opt] ]
     [ static type-qualifier-list[opt] assignment-expression ]
     [ type-qualifier-list static assignment-expression ]
     [ type-qualifier-list[opt] * ]

   parameter-type-list:
     parameter-list
     parameter-list , ...

   parameter-list:
     parameter-declaration
     parameter-list , parameter-declaration

   parameter-declaration:
     declaration-specifiers declarator gnu-attributes[opt]
     declaration-specifiers abstract-declarator[opt] gnu-attributes[opt]

   identifier-list:
     identifier
     identifier-list , identifier

   abstract-declarator:
     pointer
     pointer[opt] direct-abstract-declarator

   direct-abstract-declarator:
     ( gnu-attributes[opt] abstract-declarator )
     direct-abstract-declarator[opt] array-declarator
     direct-abstract-declarator[opt] ( parameter-type-list[opt] )

   GNU extensions:

   direct-declarator:
     direct-declarator ( parameter-forward-declarations
                         parameter-type-list[opt] )

   direct-abstract-declarator:
     direct-abstract-declarator[opt] ( parameter-forward-declarations
                                       parameter-type-list[opt] )

   parameter-forward-declarations:
     parameter-list ;
     parameter-forward-declarations parameter-list ;

   The uses of gnu-attributes shown above are GNU extensions.

   Some forms of array declarator are not included in C99 in the
   syntax for abstract declarators; these are disallowed elsewhere.
   This may be a defect (DR#289).

   This function also accepts an omitted abstract declarator as being
   an abstract declarator, although not part of the formal syntax.  */

struct c_declarator *
c_parser_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind,
                     bool *seen_id)
{
  /* Parse any initial pointer part.  */
  if (c_parser_next_token_is (parser, CPP_MULT))
    {
      struct c_declspecs *quals_attrs = build_null_declspecs ();
      struct c_declarator *inner;
      c_parser_consume_token (parser);
      c_parser_declspecs (parser, quals_attrs, false, false, true,
                          false, false, true, false, cla_prefer_id);
      inner = c_parser_declarator (parser, type_seen_p, kind, seen_id);
      if (inner == NULL)
        return NULL;
      else
        return make_pointer_declarator (quals_attrs, inner);
    }
  /* Now we have a direct declarator, direct abstract declarator or
     nothing (which counts as a direct abstract declarator here).  */
  return c_parser_direct_declarator (parser, type_seen_p, kind, seen_id);
}

/* Parse a direct declarator or direct abstract declarator; arguments
   as c_parser_declarator.  */

static struct c_declarator *
c_parser_direct_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind,
                            bool *seen_id)
{
  /* The direct declarator must start with an identifier (possibly
     omitted) or a parenthesized declarator (possibly abstract).  In
     an ordinary declarator, initial parentheses must start a
     parenthesized declarator.  In an abstract declarator or parameter
     declarator, they could start a parenthesized declarator or a
     parameter list.  To tell which, the open parenthesis and any
     following gnu-attributes must be read.  If a declaration
     specifier or standard attributes follow, then it is a parameter
     list; if the specifier is a typedef name, there might be an
     ambiguity about redeclaring it, which is resolved in the
     direction of treating it as a typedef name.  If a close
     parenthesis follows, it is also an empty parameter list, as the
     syntax does not permit empty abstract declarators.  Otherwise, it
     is a parenthesized declarator (in which case the analysis may be
     repeated inside it, recursively).

     ??? There is an ambiguity in a parameter declaration "int
     (__attribute__((foo)) x)", where x is not a typedef name: it
     could be an abstract declarator for a function, or declare x with
     parentheses.  The proper resolution of this ambiguity needs
     documenting.  At present we follow an accident of the old
     parser's implementation, whereby the first parameter must have
     some declaration specifiers other than just gnu-attributes.  Thus as
     a parameter declaration it is treated as a parenthesized
     parameter named x, and as an abstract declarator it is
     rejected.

     ??? Also following the old parser, gnu-attributes inside an empty
     parameter list are ignored, making it a list not yielding a
     prototype, rather than giving an error or making it have one
     parameter with implicit type int.

     ??? Also following the old parser, typedef names may be
     redeclared in declarators, but not Objective-C class names.  */

  if (kind != C_DTR_ABSTRACT
      && c_parser_next_token_is (parser, CPP_NAME)
      && ((type_seen_p
           && (c_parser_peek_token (parser)->id_kind == C_ID_TYPENAME
               || c_parser_peek_token (parser)->id_kind == C_ID_CLASSNAME))
          || c_parser_peek_token (parser)->id_kind == C_ID_ID))
    {
      struct c_declarator *inner
        = build_id_declarator (c_parser_peek_token (parser)->value);
      *seen_id = true;
      inner->id_loc = c_parser_peek_token (parser)->location;
      c_parser_consume_token (parser);
      if (c_parser_nth_token_starts_std_attributes (parser, 1))
        inner->u.id.attrs = c_parser_std_attribute_specifier_sequence (parser);
      return c_parser_direct_declarator_inner (parser, *seen_id, inner);
    }

  if (kind != C_DTR_NORMAL
      && c_parser_next_token_is (parser, CPP_OPEN_SQUARE)
      && !c_parser_nth_token_starts_std_attributes (parser, 1))
    {
      struct c_declarator *inner = build_id_declarator (NULL_TREE);
      inner->id_loc = c_parser_peek_token (parser)->location;
      return c_parser_direct_declarator_inner (parser, *seen_id, inner);
    }

  /* Either we are at the end of an abstract declarator, or we have
     parentheses.  */

  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      tree attrs;
      struct c_declarator *inner;
      c_parser_consume_token (parser);
      bool have_gnu_attrs = c_parser_next_token_is_keyword (parser,
                                                            RID_ATTRIBUTE);
      attrs = c_parser_gnu_attributes (parser);
      if (kind != C_DTR_NORMAL
          && (c_parser_next_token_starts_declspecs (parser)
              || (!have_gnu_attrs
                  && (c_parser_nth_token_starts_std_attributes (parser, 1)
                      || c_parser_next_token_is (parser, CPP_ELLIPSIS)))
              || c_parser_next_token_is (parser, CPP_CLOSE_PAREN)))
        {
          struct c_arg_info *args
            = c_parser_parms_declarator (parser, kind == C_DTR_NORMAL,
                                         attrs, have_gnu_attrs);
          if (args == NULL)
            return NULL;
          else
            {
              inner = build_id_declarator (NULL_TREE);
              if (!(args->types
                    && args->types != error_mark_node
                    && TREE_CODE (TREE_VALUE (args->types)) == IDENTIFIER_NODE)
                  && c_parser_nth_token_starts_std_attributes (parser, 1))
                {
                  tree std_attrs
                    = c_parser_std_attribute_specifier_sequence (parser);
                  if (std_attrs)
                    inner = build_attrs_declarator (std_attrs, inner);
                }
              inner = build_function_declarator (args, inner);
              return c_parser_direct_declarator_inner (parser, *seen_id,
                                                       inner);
            }
        }
      /* A parenthesized declarator.  */
      inner = c_parser_declarator (parser, type_seen_p, kind, seen_id);
      if (inner != NULL && attrs != NULL)
        inner = build_attrs_declarator (attrs, inner);
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          c_parser_consume_token (parser);
          if (inner == NULL)
            return NULL;
          else
            return c_parser_direct_declarator_inner (parser, *seen_id, inner);
        }
      else
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return NULL;
        }
    }
  else
    {
      if (kind == C_DTR_NORMAL)
        {
          c_parser_error (parser, "expected identifier or %<(%>");
          return NULL;
        }
      else
        return build_id_declarator (NULL_TREE);
    }
}

/* Parse part of a direct declarator or direct abstract declarator,
   given that some (in INNER) has already been parsed; ID_PRESENT is
   true if an identifier is present, false for an abstract
   declarator.  */

static struct c_declarator *
c_parser_direct_declarator_inner (c_parser *parser, bool id_present,
                                  struct c_declarator *inner)
{
  /* Parse a sequence of array declarators and parameter lists.  */
  if (c_parser_next_token_is (parser, CPP_OPEN_SQUARE)
      && !c_parser_nth_token_starts_std_attributes (parser, 1))
    {
      location_t brace_loc = c_parser_peek_token (parser)->location;
      struct c_declarator *declarator;
      struct c_declspecs *quals_attrs = build_null_declspecs ();
      bool static_seen;
      bool star_seen;
      struct c_expr dimen;
      dimen.value = NULL_TREE;
      dimen.original_code = ERROR_MARK;
      dimen.original_type = NULL_TREE;
      c_parser_consume_token (parser);
      c_parser_declspecs (parser, quals_attrs, false, false, true,
                          false, false, false, false, cla_prefer_id);
      static_seen = c_parser_next_token_is_keyword (parser, RID_STATIC);
      if (static_seen)
        c_parser_consume_token (parser);
      if (static_seen && !quals_attrs->declspecs_seen_p)
        c_parser_declspecs (parser, quals_attrs, false, false, true,
                            false, false, false, false, cla_prefer_id);
      if (!quals_attrs->declspecs_seen_p)
        quals_attrs = NULL;
      /* If "static" is present, there must be an array dimension.
         Otherwise, there may be a dimension, "*", or no
         dimension.  */
      if (static_seen)
        {
          star_seen = false;
          dimen = c_parser_expr_no_commas (parser, NULL);
        }
      else
        {
          if (c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
            {
              dimen.value = NULL_TREE;
              star_seen = false;
            }
          else if (c_parser_next_token_is (parser, CPP_MULT))
            {
              if (c_parser_peek_2nd_token (parser)->type == CPP_CLOSE_SQUARE)
                {
                  dimen.value = NULL_TREE;
                  star_seen = true;
                  c_parser_consume_token (parser);
                }
              else
                {
                  star_seen = false;
                  dimen = c_parser_expr_no_commas (parser, NULL);
                }
            }
          else
            {
              star_seen = false;
              dimen = c_parser_expr_no_commas (parser, NULL);
            }
        }
      if (c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
        c_parser_consume_token (parser);
      else
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                     "expected %<]%>");
          return NULL;
        }
      if (dimen.value)
        dimen = convert_lvalue_to_rvalue (brace_loc, dimen, true, true);
      declarator = build_array_declarator (brace_loc, dimen.value, quals_attrs,
                                           static_seen, star_seen);
      if (declarator == NULL)
        return NULL;
      if (c_parser_nth_token_starts_std_attributes (parser, 1))
        {
          tree std_attrs
            = c_parser_std_attribute_specifier_sequence (parser);
          if (std_attrs)
            inner = build_attrs_declarator (std_attrs, inner);
        }
      inner = set_array_declarator_inner (declarator, inner);
      return c_parser_direct_declarator_inner (parser, id_present, inner);
    }
  else if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      tree attrs;
      struct c_arg_info *args;
      c_parser_consume_token (parser);
      bool have_gnu_attrs = c_parser_next_token_is_keyword (parser,
                                                            RID_ATTRIBUTE);
      attrs = c_parser_gnu_attributes (parser);
      args = c_parser_parms_declarator (parser, id_present, attrs,
                                        have_gnu_attrs);
      if (args == NULL)
        return NULL;
      else
        {
          if (!(args->types
                && args->types != error_mark_node
                && TREE_CODE (TREE_VALUE (args->types)) == IDENTIFIER_NODE)
              && c_parser_nth_token_starts_std_attributes (parser, 1))
            {
              tree std_attrs
                = c_parser_std_attribute_specifier_sequence (parser);
              if (std_attrs)
                inner = build_attrs_declarator (std_attrs, inner);
            }
          inner = build_function_declarator (args, inner);
          return c_parser_direct_declarator_inner (parser, id_present, inner);
        }
    }
  return inner;
}

/* Parse a parameter list or identifier list, including the closing
   parenthesis but not the opening one.  ATTRS are the gnu-attributes
   at the start of the list.  ID_LIST_OK is true if an identifier list
   is acceptable; such a list must not have attributes at the start.
   HAVE_GNU_ATTRS says whether any gnu-attributes (including empty
   attributes) were present (in which case standard attributes cannot
   occur).  */

static struct c_arg_info *
c_parser_parms_declarator (c_parser *parser, bool id_list_ok, tree attrs,
                           bool have_gnu_attrs)
{
  push_scope ();
  declare_parm_level ();
  /* If the list starts with an identifier, it is an identifier list.
     Otherwise, it is either a prototype list or an empty list.  */
  if (id_list_ok
      && !attrs
      && c_parser_next_token_is (parser, CPP_NAME)
      && c_parser_peek_token (parser)->id_kind == C_ID_ID
      
      /* Look ahead to detect typos in type names.  */
      && c_parser_peek_2nd_token (parser)->type != CPP_NAME
      && c_parser_peek_2nd_token (parser)->type != CPP_MULT
      && c_parser_peek_2nd_token (parser)->type != CPP_OPEN_PAREN
      && c_parser_peek_2nd_token (parser)->type != CPP_OPEN_SQUARE
      && c_parser_peek_2nd_token (parser)->type != CPP_KEYWORD)
    {
      tree list = NULL_TREE, *nextp = &list;
      while (c_parser_next_token_is (parser, CPP_NAME)
             && c_parser_peek_token (parser)->id_kind == C_ID_ID)
        {
          *nextp = build_tree_list (NULL_TREE,
                                    c_parser_peek_token (parser)->value);
          nextp = & TREE_CHAIN (*nextp);
          c_parser_consume_token (parser);
          if (c_parser_next_token_is_not (parser, CPP_COMMA))
            break;
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
            {
              c_parser_error (parser, "expected identifier");
              break;
            }
        }
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          struct c_arg_info *ret = build_arg_info ();
          ret->types = list;
          c_parser_consume_token (parser);
          pop_scope ();
          return ret;
        }
      else
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          pop_scope ();
          return NULL;
        }
    }
  else
    {
      struct c_arg_info *ret
        = c_parser_parms_list_declarator (parser, attrs, NULL, have_gnu_attrs);
      pop_scope ();
      return ret;
    }
}

/* Parse a parameter list (possibly empty), including the closing
   parenthesis but not the opening one.  ATTRS are the gnu-attributes
   at the start of the list; if HAVE_GNU_ATTRS, there were some such
   attributes (possibly empty, in which case ATTRS is NULL_TREE),
   which means standard attributes cannot start the list.  EXPR is
   NULL or an expression that needs to be evaluated for the side
   effects of array size expressions in the parameters.  */

static struct c_arg_info *
c_parser_parms_list_declarator (c_parser *parser, tree attrs, tree expr,
                                bool have_gnu_attrs)
{
  bool bad_parm = false;

  /* ??? Following the old parser, forward parameter declarations may
     use abstract declarators, and if no real parameter declarations
     follow the forward declarations then this is not diagnosed.  Also
     note as above that gnu-attributes are ignored as the only contents of
     the parentheses, or as the only contents after forward
     declarations.  */
  if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
    {
      struct c_arg_info *ret = build_arg_info ();
      c_parser_consume_token (parser);
      return ret;
    }
  if (c_parser_next_token_is (parser, CPP_ELLIPSIS) && !have_gnu_attrs)
    {
      struct c_arg_info *ret = build_arg_info ();

      ret->types = NULL_TREE;
      pedwarn_c11 (c_parser_peek_token (parser)->location, OPT_Wpedantic,
                   "ISO C requires a named argument before %<...%> "
                   "before C23");
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          ret->no_named_args_stdarg_p = true;
          c_parser_consume_token (parser);
          return ret;
        }
      else
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return NULL;
        }
    }
  /* Nonempty list of parameters, either terminated with semicolon
     (forward declarations; recurse) or with close parenthesis (normal
     function) or with ", ... )" (variadic function).  */
  while (true)
    {
      /* Parse a parameter.  */
      struct c_parm *parm = c_parser_parameter_declaration (parser, attrs,
                                                            have_gnu_attrs);
      attrs = NULL_TREE;
      have_gnu_attrs = false;
      if (parm == NULL)
        bad_parm = true;
      else
        push_parm_decl (parm, &expr);
      if (c_parser_next_token_is (parser, CPP_SEMICOLON))
        {
          tree new_attrs;
          c_parser_consume_token (parser);
          mark_forward_parm_decls ();
          bool new_have_gnu_attrs
            = c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE);
          new_attrs = c_parser_gnu_attributes (parser);
          return c_parser_parms_list_declarator (parser, new_attrs, expr,
                                                 new_have_gnu_attrs);
        }
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          c_parser_consume_token (parser);
          if (bad_parm)
            return NULL;
          else
            return get_parm_info (false, expr);
        }
      if (!c_parser_require (parser, CPP_COMMA,
                             "expected %<;%>, %<,%> or %<)%>",
                             UNKNOWN_LOCATION, false))
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          return NULL;
        }
      if (c_parser_next_token_is (parser, CPP_ELLIPSIS))
        {
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
            {
              c_parser_consume_token (parser);
              if (bad_parm)
                return NULL;
              else
                return get_parm_info (true, expr);
            }
          else
            {
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                         "expected %<)%>");
              return NULL;
            }
        }
    }
}

/* Parse a parameter declaration.  ATTRS are the gnu-attributes at the
   start of the declaration if it is the first parameter;
   HAVE_GNU_ATTRS is true if there were any gnu-attributes there (even
   empty) there.  */

static struct c_parm *
c_parser_parameter_declaration (c_parser *parser, tree attrs,
                                bool have_gnu_attrs)
{
  struct c_declspecs *specs;
  struct c_declarator *declarator;
  tree prefix_attrs;
  tree postfix_attrs = NULL_TREE;
  bool dummy = false;

  /* Accept #pragmas between parameter declarations.  */
  while (c_parser_next_token_is (parser, CPP_PRAGMA))
    c_parser_pragma (parser, pragma_param, NULL);

  if (!c_parser_next_token_starts_declspecs (parser)
      && !c_parser_nth_token_starts_std_attributes (parser, 1))
    {
      c_token *token = c_parser_peek_token (parser);
      if (parser->error)
        return NULL;
      c_parser_set_source_position_from_token (token);
      if (c_parser_next_tokens_start_typename (parser, cla_prefer_type))
        {
          auto_diagnostic_group d;
          name_hint hint = lookup_name_fuzzy (token->value,
                                              FUZZY_LOOKUP_TYPENAME,
                                              token->location);
          if (const char *suggestion = hint.suggestion ())
            {
              gcc_rich_location richloc (token->location);
              richloc.add_fixit_replace (suggestion);
              error_at (&richloc,
                        "unknown type name %qE; did you mean %qs?",
                        token->value, suggestion);
            }
          else
            error_at (token->location, "unknown type name %qE", token->value);
          parser->error = true;
        }
      /* ??? In some Objective-C cases '...' isn't applicable so there
         should be a different message.  */
      else
        c_parser_error (parser,
                        "expected declaration specifiers or %<...%>");
      c_parser_skip_to_end_of_parameter (parser);
      return NULL;
    }

  location_t start_loc = c_parser_peek_token (parser)->location;

  specs = build_null_declspecs ();
  if (attrs)
    {
      declspecs_add_attrs (input_location, specs, attrs);
      attrs = NULL_TREE;
    }
  c_parser_declspecs (parser, specs, true, true, true, true, false,
                      !have_gnu_attrs, true, cla_nonabstract_decl);
  finish_declspecs (specs);
  pending_xref_error ();
  prefix_attrs = specs->attrs;
  specs->attrs = NULL_TREE;
  declarator = c_parser_declarator (parser,
                                    specs->typespec_kind != ctsk_none,
                                    C_DTR_PARM, &dummy);
  if (declarator == NULL)
    {
      c_parser_skip_until_found (parser, CPP_COMMA, NULL);
      return NULL;
    }
  if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
    postfix_attrs = c_parser_gnu_attributes (parser);

  /* Generate a location for the parameter, ranging from the start of the
     initial token to the end of the final token.

     If we have a identifier, then use it for the caret location, e.g.

       extern int callee (int one, int (*two)(int, int), float three);
                                   ~~~~~~^~~~~~~~~~~~~~

     otherwise, reuse the start location for the caret location e.g.:

       extern int callee (int one, int (*)(int, int), float three);
                                   ^~~~~~~~~~~~~~~~~
  */
  location_t end_loc = parser->last_token_location;

  /* Find any cdk_id declarator; determine if we have an identifier.  */
  c_declarator *id_declarator = declarator;
  while (id_declarator && id_declarator->kind != cdk_id)
    id_declarator = id_declarator->declarator;
  location_t caret_loc = (id_declarator->u.id.id
                          ? id_declarator->id_loc
                          : start_loc);
  location_t param_loc = make_location (caret_loc, start_loc, end_loc);

  return build_c_parm (specs, chainon (postfix_attrs, prefix_attrs),
                       declarator, param_loc);
}

/* Parse a string literal in an asm expression.  It should not be
   translated, and wide string literals are an error although
   permitted by the syntax.  This is a GNU extension.

   asm-string-literal:
     string-literal
*/

static tree
c_parser_asm_string_literal (c_parser *parser)
{
  tree str;
  int save_flag = warn_overlength_strings;
  warn_overlength_strings = 0;
  str = c_parser_string_literal (parser, false, false).value;
  warn_overlength_strings = save_flag;
  return str;
}

/* Parse a simple asm expression.  This is used in restricted
   contexts, where a full expression with inputs and outputs does not
   make sense.  This is a GNU extension.

   simple-asm-expr:
     asm ( asm-string-literal )
*/

static tree
c_parser_simple_asm_expr (c_parser *parser)
{
  tree str;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_ASM));
  c_parser_consume_token (parser);
  matching_parens parens;
  if (!parens.require_open (parser))
    return NULL_TREE;
  str = c_parser_asm_string_literal (parser);
  if (!parens.require_close (parser))
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
      return NULL_TREE;
    }
  return str;
}

static tree
c_parser_gnu_attribute_any_word (c_parser *parser)
{
  tree attr_name = NULL_TREE;

  if (c_parser_next_token_is (parser, CPP_KEYWORD))
    {
      /* ??? See comment above about what keywords are accepted here.  */
      bool ok;
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_STATIC:
        case RID_UNSIGNED:
        case RID_LONG:
        case RID_CONST:
        case RID_EXTERN:
        case RID_REGISTER:
        case RID_TYPEDEF:
        case RID_SHORT:
        case RID_INLINE:
        case RID_NORETURN:
        case RID_VOLATILE:
        case RID_SIGNED:
        case RID_AUTO:
        case RID_RESTRICT:
        case RID_COMPLEX:
        case RID_THREAD:
        case RID_INT:
        case RID_CHAR:
        case RID_FLOAT:
        case RID_DOUBLE:
        case RID_VOID:
        case RID_DFLOAT32:
        case RID_DFLOAT64:
        case RID_DFLOAT128:
        CASE_RID_FLOATN_NX:
        case RID_BOOL:
        case RID_BITINT:
        case RID_FRACT:
        case RID_ACCUM:
        case RID_SAT:
        case RID_TRANSACTION_ATOMIC:
        case RID_TRANSACTION_CANCEL:
        case RID_ATOMIC:
        case RID_AUTO_TYPE:
        case RID_CONSTEXPR:
        case RID_INT_N_0:
        case RID_INT_N_1:
        case RID_INT_N_2:
        case RID_INT_N_3:
          ok = true;
          break;
        default:
          ok = false;
          break;
        }
      if (!ok)
        return NULL_TREE;

      /* Accept __attribute__((__const)) as __attribute__((const)) etc.  */
      attr_name = ridpointers[(int) c_parser_peek_token (parser)->keyword];
    }
  else if (c_parser_next_token_is (parser, CPP_NAME))
    attr_name = c_parser_peek_token (parser)->value;

  return attr_name;
}

/* Parse attribute arguments.  This is a common form of syntax
   covering all currently valid GNU and standard attributes.

   gnu-attribute-arguments:
     identifier
     identifier , nonempty-expr-list
     expr-list

   where the "identifier" must not be declared as a type.  ??? Why not
   allow identifiers declared as types to start the arguments?  */

static tree
c_parser_attribute_arguments (c_parser *parser, bool takes_identifier,
                              bool require_string, bool assume_attr,
                              bool allow_empty_args)
{
  vec<tree, va_gc> *expr_list;
  tree attr_args;
  /* Parse the attribute contents.  If they start with an
     identifier which is followed by a comma or close
     parenthesis, then the arguments start with that
     identifier; otherwise they are an expression list.
     In objective-c the identifier may be a classname.  */
  if (c_parser_next_token_is (parser, CPP_NAME)
      && (c_parser_peek_token (parser)->id_kind == C_ID_ID
          || (c_dialect_objc ()
              && c_parser_peek_token (parser)->id_kind
              == C_ID_CLASSNAME))
      && ((c_parser_peek_2nd_token (parser)->type == CPP_COMMA)
          || (c_parser_peek_2nd_token (parser)->type
              == CPP_CLOSE_PAREN))
      && (takes_identifier
          || (c_dialect_objc ()
              && !assume_attr
              && c_parser_peek_token (parser)->id_kind
              == C_ID_CLASSNAME)))
    {
      tree arg1 = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        attr_args = build_tree_list (NULL_TREE, arg1);
      else
        {
          tree tree_list;
          c_parser_consume_token (parser);
          expr_list = c_parser_expr_list (parser, false, true,
                                          NULL, NULL, NULL, NULL);
          tree_list = build_tree_list_vec (expr_list);
          attr_args = tree_cons (NULL_TREE, arg1, tree_list);
          release_tree_vector (expr_list);
        }
    }
  else
    {
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          if (!allow_empty_args)
            error_at (c_parser_peek_token (parser)->location,
                      "parentheses must be omitted if "
                      "attribute argument list is empty");
          attr_args = NULL_TREE;
        }
      else if (require_string)
        {
          /* The only valid argument for this attribute is a string
             literal.  Handle this specially here to avoid accepting
             string literals with excess parentheses.  */
          tree string = c_parser_string_literal (parser, false, true).value;
          attr_args = build_tree_list (NULL_TREE, string);
        }
      else if (assume_attr)
        {
          tree cond
            = c_parser_conditional_expression (parser, NULL, NULL_TREE).value;
          if (!c_parser_next_token_is (parser, CPP_COMMA))
            attr_args = build_tree_list (NULL_TREE, cond);
          else
            {
              tree tree_list;
              c_parser_consume_token (parser);
              expr_list = c_parser_expr_list (parser, false, true,
                                              NULL, NULL, NULL, NULL);
              tree_list = build_tree_list_vec (expr_list);
              attr_args = tree_cons (NULL_TREE, cond, tree_list);
              release_tree_vector (expr_list);
            }
        }
      else
        {
          expr_list = c_parser_expr_list (parser, false, true,
                                          NULL, NULL, NULL, NULL);
          attr_args = build_tree_list_vec (expr_list);
          release_tree_vector (expr_list);
        }
    }
  return attr_args;
}

/* Parse (possibly empty) gnu-attributes.  This is a GNU extension.

   gnu-attributes:
     empty
     gnu-attributes gnu-attribute

   gnu-attribute:
     __attribute__ ( ( gnu-attribute-list ) )

   gnu-attribute-list:
     gnu-attrib
     gnu-attribute_list , gnu-attrib

   gnu-attrib:
     empty
     any-word
     any-word ( gnu-attribute-arguments )

   where "any-word" may be any identifier (including one declared as a
   type), a reserved word storage class specifier, type specifier or
   type qualifier.  ??? This still leaves out most reserved keywords
   (following the old parser), shouldn't we include them?
   When EXPECT_COMMA is true, expect the attribute to be preceded
   by a comma and fail if it isn't.
   When EMPTY_OK is true, allow and consume any number of consecutive
   commas with no attributes in between.  */

static tree
c_parser_gnu_attribute (c_parser *parser, tree attrs,
                        bool expect_comma = false, bool empty_ok = true)
{
  bool comma_first = c_parser_next_token_is (parser, CPP_COMMA);
  if (!comma_first
      && !c_parser_next_token_is (parser, CPP_NAME)
      && !c_parser_next_token_is (parser, CPP_KEYWORD))
    return NULL_TREE;

  while (c_parser_next_token_is (parser, CPP_COMMA))
    {
      c_parser_consume_token (parser);
      if (!empty_ok)
        return attrs;
    }

  tree attr_name = c_parser_gnu_attribute_any_word (parser);
  if (attr_name == NULL_TREE)
    return NULL_TREE;

  attr_name = canonicalize_attr_name (attr_name);
  c_parser_consume_token (parser);

  tree attr;
  if (c_parser_next_token_is_not (parser, CPP_OPEN_PAREN))
    {
      if (expect_comma && !comma_first)
        {
          /* A comma is missing between the last attribute on the chain
             and this one.  */
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return error_mark_node;
        }
      attr = build_tree_list (attr_name, NULL_TREE);
      /* Add this attribute to the list.  */
      attrs = chainon (attrs, attr);
      return attrs;
    }
  c_parser_consume_token (parser);

  tree attr_args
    = c_parser_attribute_arguments (parser,
                                    attribute_takes_identifier_p (attr_name),
                                    false,
                                    is_attribute_p ("assume", attr_name),
                                    true);

  attr = build_tree_list (attr_name, attr_args);
  if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
    c_parser_consume_token (parser);
  else
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                 "expected %<)%>");
      return error_mark_node;
    }

  if (expect_comma && !comma_first)
    {
      /* A comma is missing between the last attribute on the chain
         and this one.  */
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                 "expected %<)%>");
      return error_mark_node;
    }

  /* Add this attribute to the list.  */
  attrs = chainon (attrs, attr);
  return attrs;
}

static tree
c_parser_gnu_attributes (c_parser *parser)
{
  tree attrs = NULL_TREE;
  while (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
    {
      bool save_translate_strings_p = parser->translate_strings_p;
      parser->translate_strings_p = false;
      /* Consume the `__attribute__' keyword.  */
      c_parser_consume_token (parser);
      /* Look for the two `(' tokens.  */
      if (!c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
        {
          parser->translate_strings_p = save_translate_strings_p;
          return attrs;
        }
      if (!c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
        {
          parser->translate_strings_p = save_translate_strings_p;
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          return attrs;
        }
      /* Parse the attribute list.  Require a comma between successive
         (possibly empty) attributes.  */
      for (bool expect_comma = false; ; expect_comma = true)
        {
          /* Parse a single attribute.  */
          tree attr = c_parser_gnu_attribute (parser, attrs, expect_comma);
          if (attr == error_mark_node)
            return attrs;
          if (!attr)
            break;
          attrs = attr;
      }

      /* Look for the two `)' tokens.  */
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        c_parser_consume_token (parser);
      else
        {
          parser->translate_strings_p = save_translate_strings_p;
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return attrs;
        }
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        c_parser_consume_token (parser);
      else
        {
          parser->translate_strings_p = save_translate_strings_p;
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return attrs;
        }
      parser->translate_strings_p = save_translate_strings_p;
    }

  return attrs;
}

/* Parse an optional balanced token sequence.

   balanced-token-sequence:
     balanced-token
     balanced-token-sequence balanced-token

   balanced-token:
     ( balanced-token-sequence[opt] )
     [ balanced-token-sequence[opt] ]
     { balanced-token-sequence[opt] }
     any token other than ()[]{}
*/

static void
c_parser_balanced_token_sequence (c_parser *parser)
{
  while (true)
    {
      c_token *token = c_parser_peek_token (parser);
      switch (token->type)
        {
        case CPP_OPEN_BRACE:
          {
            matching_braces braces;
            braces.consume_open (parser);
            c_parser_balanced_token_sequence (parser);
            braces.require_close (parser);
            break;
          }

        case CPP_OPEN_PAREN:
          {
            matching_parens parens;
            parens.consume_open (parser);
            c_parser_balanced_token_sequence (parser);
            parens.require_close (parser);
            break;
          }

        case CPP_OPEN_SQUARE:
          c_parser_consume_token (parser);
          c_parser_balanced_token_sequence (parser);
          c_parser_require (parser, CPP_CLOSE_SQUARE, "expected %<]%>");
          break;

        case CPP_CLOSE_BRACE:
        case CPP_CLOSE_PAREN:
        case CPP_CLOSE_SQUARE:
        case CPP_EOF:
          return;

        case CPP_PRAGMA:
          c_parser_consume_pragma (parser);
          c_parser_skip_to_pragma_eol (parser, false);
          break;

        default:
          c_parser_consume_token (parser);
          break;
        }
    }
}

static bool c_parser_check_balanced_raw_token_sequence (c_parser *,
                                                        unsigned int *);

/* Parse arguments of omp::directive or omp::decl attribute.

   directive-name ,[opt] clause-list[opt]

   For directive just remember the tokens in a vector for subsequent
   parsing.  */

static void
c_parser_omp_directive_args (c_parser *parser, tree attribute, bool decl_p)
{
  unsigned int n = 1;
  c_token *first = c_parser_peek_token (parser);
  if (!c_parser_check_balanced_raw_token_sequence (parser, &n)
      || (c_parser_peek_nth_token_raw (parser, n)->type
          != CPP_CLOSE_PAREN))
    {
      c_parser_balanced_token_sequence (parser);
      TREE_VALUE (attribute) = NULL_TREE;
      return;
    }
  if (n == 1)
    {
      error_at (first->location, "expected OpenMP directive name");
      TREE_VALUE (attribute) = NULL_TREE;
      return;
    }
  vec<c_token, va_gc> *v;
  vec_alloc (v, n - 1);
  for (--n; n; --n)
    {
      c_token *tok = c_parser_peek_token (parser);
      v->quick_push (*tok);
      c_parser_consume_token (parser);
    }
  tree arg = make_node (C_TOKEN_VEC);
  C_TOKEN_VEC_TOKENS (arg) = v;
  if (decl_p)
    TREE_PUBLIC (arg) = 1;
  TREE_VALUE (attribute) = tree_cons (NULL_TREE, arg, TREE_VALUE (attribute));
}

/* Parse arguments of omp::sequence attribute.

   omp::[opt] directive-attr [ , omp::[opt] directive-attr ]...  */

static void
c_parser_omp_sequence_args (c_parser *parser, tree attribute)
{
  do
    {
      c_token *token = c_parser_peek_token (parser);
      if (token->type == CPP_NAME
          && strcmp (IDENTIFIER_POINTER (token->value), "omp") == 0
          && c_parser_peek_2nd_token (parser)->type == CPP_SCOPE)
        {
          c_parser_consume_token (parser);
          c_parser_consume_token (parser);
          token = c_parser_peek_token (parser);
        }
      bool directive = false;
      const char *p;
      if (token->type != CPP_NAME)
        p = "";
      else
        p = IDENTIFIER_POINTER (token->value);
      if (strcmp (p, "directive") == 0)
        directive = true;
      else if (strcmp (p, "sequence") != 0)
        {
          error_at (token->location, "expected %<directive%> or %<sequence%>");
          unsigned nesting_depth = 0;

          while (true)
            {
              /* Peek at the next token.  */
              token = c_parser_peek_token (parser);
              /* If we've reached the token we want, consume it and stop.  */
              if ((token->type == CPP_CLOSE_PAREN || token->type == CPP_COMMA)
                  && !nesting_depth)
                break;
              /* If we've run out of tokens, stop.  */
              if (token->type == CPP_EOF)
                break;
              if (token->type == CPP_PRAGMA_EOL && parser->in_pragma)
                break;
              if (token->type == CPP_OPEN_BRACE
                  || token->type == CPP_OPEN_PAREN
                  || token->type == CPP_OPEN_SQUARE)
                ++nesting_depth;
              else if (token->type == CPP_CLOSE_BRACE
                       || token->type == CPP_CLOSE_PAREN
                       || token->type == CPP_CLOSE_SQUARE)
                {
                  if (nesting_depth-- == 0)
                    break;
                }
              /* Consume this token.  */
              c_parser_consume_token (parser);
            }
          if (c_parser_next_token_is_not (parser, CPP_COMMA))
            break;
          c_parser_consume_token (parser);
          continue;
        }
      c_parser_consume_token (parser);
      matching_parens parens;
      if (parens.require_open (parser))
        {
          if (directive)
            c_parser_omp_directive_args (parser, attribute, false);
          else
            c_parser_omp_sequence_args (parser, attribute);
          parens.skip_until_found_close (parser);
          if (c_parser_next_token_is_not (parser, CPP_COMMA))
            break;
          c_parser_consume_token (parser);
        }
      else if (c_parser_next_token_is_not (parser, CPP_COMMA))
        break;
      else
        c_parser_consume_token (parser);
    }
  while (1);
}

/* Parse standard (C23) attributes (including GNU attributes in the
   gnu:: namespace).

   attribute-specifier-sequence:
     attribute-specifier-sequence[opt] attribute-specifier

   attribute-specifier:
     [ [ attribute-list ] ]

   attribute-list:
     attribute[opt]
     attribute-list, attribute[opt]

   attribute:
     attribute-token attribute-argument-clause[opt]

   attribute-token:
     standard-attribute
     attribute-prefixed-token

   standard-attribute:
     identifier

   attribute-prefixed-token:
     attribute-prefix :: identifier

   attribute-prefix:
     identifier

   attribute-argument-clause:
     ( balanced-token-sequence[opt] )

   Keywords are accepted as identifiers for this purpose.

   As an extension, we permit an attribute-specifier to be:

     [ [ __extension__ attribute-list ] ]

   Two colons are then accepted as a synonym for ::.  No attempt is made
   to check whether the colons are immediately adjacent.  LOOSE_SCOPE_P
   indicates whether this relaxation is in effect.  */

static tree
c_parser_std_attribute (c_parser *parser, bool for_tm,
                        bool loose_scope_p = false)
{
  c_token *token = c_parser_peek_token (parser);
  tree ns, name, attribute;

  /* Parse the attribute-token.  */
  if (token->type != CPP_NAME && token->type != CPP_KEYWORD)
    {
      c_parser_error (parser, "expected identifier");
      return error_mark_node;
    }
  name = canonicalize_attr_name (token->value);
  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_SCOPE)
      || (loose_scope_p
          && c_parser_next_token_is (parser, CPP_COLON)
          && c_parser_peek_2nd_token (parser)->type == CPP_COLON))
    {
      ns = name;
      if (c_parser_next_token_is (parser, CPP_COLON))
        c_parser_consume_token (parser);
      c_parser_consume_token (parser);
      token = c_parser_peek_token (parser);
      if (token->type != CPP_NAME && token->type != CPP_KEYWORD)
        {
          c_parser_error (parser, "expected identifier");
          return error_mark_node;
        }
      name = canonicalize_attr_name (token->value);
      c_parser_consume_token (parser);
    }
  else
    ns = NULL_TREE;
  attribute = build_tree_list (build_tree_list (ns, name), NULL_TREE);

  /* Parse the arguments, if any.  */
  const attribute_spec *as = lookup_attribute_spec (TREE_PURPOSE (attribute));
  if (c_parser_next_token_is_not (parser, CPP_OPEN_PAREN))
    {
      if ((flag_openmp || flag_openmp_simd)
          && ns
          && is_attribute_p ("omp", ns)
          && (is_attribute_p ("directive", name)
              || is_attribute_p ("sequence", name)
              || is_attribute_p ("decl", name)))
        {
          error ("%<omp::%E%> attribute requires argument", name);
          return error_mark_node;
        }
      goto out;
    }
  {
    location_t open_loc = c_parser_peek_token (parser)->location;
    matching_parens parens;
    parens.consume_open (parser);
    if ((as && as->max_length == 0)
        /* Special-case the transactional-memory attribute "outer",
           which is specially handled but not registered as an
           attribute, to avoid allowing arbitrary balanced token
           sequences as arguments.  */
        || is_attribute_p ("outer", name))
      {
        error_at (open_loc, "%qE attribute does not take any arguments", name);
        parens.skip_until_found_close (parser);
        return error_mark_node;
      }
    /* If this is a fake attribute created to handle -Wno-attributes,
       we must skip parsing the arguments.  */
    if (as && !attribute_ignored_p (as))
      {
        bool takes_identifier
          = (ns != NULL_TREE
             && strcmp (IDENTIFIER_POINTER (ns), "gnu") == 0
             && attribute_takes_identifier_p (name));
        bool require_string
          = (ns == NULL_TREE
             && (strcmp (IDENTIFIER_POINTER (name), "deprecated") == 0
                 || strcmp (IDENTIFIER_POINTER (name), "nodiscard") == 0));
        bool assume_attr
          = (ns != NULL_TREE
             && strcmp (IDENTIFIER_POINTER (ns), "gnu") == 0
             && strcmp (IDENTIFIER_POINTER (name), "assume") == 0);
        TREE_VALUE (attribute)
          = c_parser_attribute_arguments (parser, takes_identifier,
                                          require_string, assume_attr, false);
      }
    else
      {
        if ((flag_openmp || flag_openmp_simd)
            && ns
            && is_attribute_p ("omp", ns))
          {
            if (is_attribute_p ("directive", name))
              {
                c_parser_omp_directive_args (parser, attribute, false);
                parens.skip_until_found_close (parser);
                return attribute;
              }
            else if (is_attribute_p ("decl", name))
              {
                TREE_VALUE (TREE_PURPOSE (attribute))
                  = get_identifier ("directive");
                c_parser_omp_directive_args (parser, attribute, true);
                parens.skip_until_found_close (parser);
                return attribute;
              }
            else if (is_attribute_p ("sequence", name))
              {
                TREE_VALUE (TREE_PURPOSE (attribute))
                  = get_identifier ("directive");
                c_parser_omp_sequence_args (parser, attribute);
                parens.skip_until_found_close (parser);
                TREE_VALUE (attribute) = nreverse (TREE_VALUE (attribute));
                return attribute;
              }
          }
        c_parser_balanced_token_sequence (parser);
      }
    parens.require_close (parser);
  }
 out:
  if (ns == NULL_TREE && !for_tm && !as)
    {
      /* An attribute with standard syntax and no namespace specified
         is a constraint violation if it is not one of the known
         standard attributes.  Diagnose it here with a pedwarn and
         then discard it to prevent a duplicate warning later.  */
      pedwarn (input_location, OPT_Wattributes, "%qE attribute ignored",
               name);
      return error_mark_node;
    }
  return attribute;
}

static tree
c_parser_std_attribute_list (c_parser *parser, bool for_tm,
                             bool loose_scope_p = false)
{
  tree attributes = NULL_TREE;
  while (true)
    {
      c_token *token = c_parser_peek_token (parser);
      if (token->type == CPP_CLOSE_SQUARE)
        break;
      if (token->type == CPP_COMMA)
        {
          c_parser_consume_token (parser);
          continue;
        }
      tree attribute = c_parser_std_attribute (parser, for_tm, loose_scope_p);
      if (attribute != error_mark_node)
        {
          TREE_CHAIN (attribute) = attributes;
          attributes = attribute;
        }
      if (c_parser_next_token_is_not (parser, CPP_COMMA))
        break;
    }
  return attributes;
}

static tree
c_parser_std_attribute_specifier (c_parser *parser, bool for_tm)
{
  location_t loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_OPEN_SQUARE, "expected %<[%>"))
    return NULL_TREE;
  if (!c_parser_require (parser, CPP_OPEN_SQUARE, "expected %<[%>"))
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE, "expected %<]%>");
      return NULL_TREE;
    }
  tree attributes;
  if (c_parser_next_token_is_keyword (parser, RID_EXTENSION))
    {
      auto ext = disable_extension_diagnostics ();
      c_parser_consume_token (parser);
      attributes = c_parser_std_attribute_list (parser, for_tm, true);
      restore_extension_diagnostics (ext);
    }
  else
    {
      if (!for_tm)
        pedwarn_c11 (loc, OPT_Wpedantic,
                     "ISO C does not support %<[[]]%> attributes before C23");
      attributes = c_parser_std_attribute_list (parser, for_tm);
    }
  c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE, "expected %<]%>");
  c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE, "expected %<]%>");
  return nreverse (attributes);
}

/* Look past an optional balanced token sequence of raw look-ahead
   tokens starting with the *Nth token.  *N is updated to point to the
   following token.  Return true if such a sequence was found, false
   if the tokens parsed were not balanced.  */

static bool
c_parser_check_balanced_raw_token_sequence (c_parser *parser, unsigned int *n)
{
  while (true)
    {
      c_token *token = c_parser_peek_nth_token_raw (parser, *n);
      switch (token->type)
        {
        case CPP_OPEN_BRACE:
          {
            ++*n;
            if (c_parser_check_balanced_raw_token_sequence (parser, n))
              {
                token = c_parser_peek_nth_token_raw (parser, *n);
                if (token->type == CPP_CLOSE_BRACE)
                  ++*n;
                else
                  return false;
              }
            else
              return false;
            break;
          }

        case CPP_OPEN_PAREN:
          {
            ++*n;
            if (c_parser_check_balanced_raw_token_sequence (parser, n))
              {
                token = c_parser_peek_nth_token_raw (parser, *n);
                if (token->type == CPP_CLOSE_PAREN)
                  ++*n;
                else
                  return false;
              }
            else
              return false;
            break;
          }

        case CPP_OPEN_SQUARE:
          {
            ++*n;
            if (c_parser_check_balanced_raw_token_sequence (parser, n))
              {
                token = c_parser_peek_nth_token_raw (parser, *n);
                if (token->type == CPP_CLOSE_SQUARE)
                  ++*n;
                else
                  return false;
              }
            else
              return false;
            break;
          }

        case CPP_CLOSE_BRACE:
        case CPP_CLOSE_PAREN:
        case CPP_CLOSE_SQUARE:
        case CPP_EOF:
          return true;

        default:
          ++*n;
          break;
        }
    }
}

/* Return whether standard attributes start with the Nth token.  */

static bool
c_parser_nth_token_starts_std_attributes (c_parser *parser, unsigned int n)
{
  if (!(c_parser_peek_nth_token (parser, n)->type == CPP_OPEN_SQUARE
        && c_parser_peek_nth_token (parser, n + 1)->type == CPP_OPEN_SQUARE))
    return false;
  /* In C, '[[' must start attributes.  In Objective-C, we need to
     check whether '[[' is matched by ']]'.  */
  if (!c_dialect_objc ())
    return true;
  n += 2;
  if (!c_parser_check_balanced_raw_token_sequence (parser, &n))
    return false;
  c_token *token = c_parser_peek_nth_token_raw (parser, n);
  if (token->type != CPP_CLOSE_SQUARE)
    return false;
  token = c_parser_peek_nth_token_raw (parser, n + 1);
  return token->type == CPP_CLOSE_SQUARE;
}

static tree
c_parser_std_attribute_specifier_sequence (c_parser *parser)
{
  tree attributes = NULL_TREE;
  do
    {
      tree attrs = c_parser_std_attribute_specifier (parser, false);
      attributes = chainon (attributes, attrs);
    }
  while (c_parser_nth_token_starts_std_attributes (parser, 1));
  return attributes;
}

/* Parse a type name (C90 6.5.5, C99 6.7.6, C11 6.7.7).  ALIGNAS_OK
   says whether alignment specifiers are OK (only in cases that might
   be the type name of a compound literal).

   type-name:
     specifier-qualifier-list abstract-declarator[opt]
*/

struct c_type_name *
c_parser_type_name (c_parser *parser, bool alignas_ok)
{
  struct c_declspecs *specs = build_null_declspecs ();
  struct c_declarator *declarator;
  struct c_type_name *ret;
  bool dummy = false;
  c_parser_declspecs (parser, specs, false, true, true, alignas_ok, false,
                      false, true, cla_prefer_type);
  if (!specs->declspecs_seen_p)
    {
      c_parser_error (parser, "expected specifier-qualifier-list");
      return NULL;
    }
  if (specs->type != error_mark_node)
    {
      pending_xref_error ();
      finish_declspecs (specs);
    }
  declarator = c_parser_declarator (parser,
                                    specs->typespec_kind != ctsk_none,
                                    C_DTR_ABSTRACT, &dummy);
  if (declarator == NULL)
    return NULL;
  ret = XOBNEW (&parser_obstack, struct c_type_name);
  ret->specs = specs;
  ret->declarator = declarator;
  return ret;
}

/* Parse an initializer (C90 6.5.7, C99 6.7.8, C11 6.7.9).

   initializer:
     assignment-expression
     { initializer-list }
     { initializer-list , }

   initializer-list:
     designation[opt] initializer
     initializer-list , designation[opt] initializer

   designation:
     designator-list =

   designator-list:
     designator
     designator-list designator

   designator:
     array-designator
     . identifier

   array-designator:
     [ constant-expression ]

   GNU extensions:

   initializer:
     { }

   designation:
     array-designator
     identifier :

   array-designator:
     [ constant-expression ... constant-expression ]

   Any expression without commas is accepted in the syntax for the
   constant-expressions, with non-constant expressions rejected later.

   DECL is the declaration we're parsing this initializer for.

   This function is only used for top-level initializers; for nested
   ones, see c_parser_initval.  */

static struct c_expr
c_parser_initializer (c_parser *parser, tree decl)
{
  if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    return c_parser_braced_init (parser, NULL_TREE, false, NULL, decl);
  else
    {
      struct c_expr ret;
      location_t loc = c_parser_peek_token (parser)->location;
      ret = c_parser_expr_no_commas (parser, NULL);
      if (decl != error_mark_node && C_DECL_VARIABLE_SIZE (decl))
        {
          error_at (loc,
                    "variable-sized object may not be initialized except "
                    "with an empty initializer");
          ret.set_error ();
        }
      /* This is handled mostly by gimplify.cc, but we have to deal with
         not warning about int x = x; as it is a GCC extension to turn off
         this warning but only if warn_init_self is zero.  */
      if (VAR_P (decl)
          && !DECL_EXTERNAL (decl)
          && !TREE_STATIC (decl)
          && ret.value == decl
          && !warning_enabled_at (DECL_SOURCE_LOCATION (decl), OPT_Winit_self))
        suppress_warning (decl, OPT_Winit_self);
      if (TREE_CODE (ret.value) != STRING_CST
          && (TREE_CODE (ret.value) != COMPOUND_LITERAL_EXPR
              || C_DECL_DECLARED_CONSTEXPR (COMPOUND_LITERAL_EXPR_DECL
                                            (ret.value))))
        ret = convert_lvalue_to_rvalue (loc, ret, true, true, true);
      return ret;
    }
}

/* The location of the last comma within the current initializer list,
   or UNKNOWN_LOCATION if not within one.  */

location_t last_init_list_comma;

/* Parse a braced initializer list.  TYPE is the type specified for a
   compound literal, and NULL_TREE for other initializers and for
   nested braced lists.  NESTED_P is true for nested braced lists,
   false for the list of a compound literal or the list that is the
   top-level initializer in a declaration.  DECL is the declaration for
   the top-level initializer for a declaration, otherwise NULL_TREE.  */

static struct c_expr
c_parser_braced_init (c_parser *parser, tree type, bool nested_p,
                      struct obstack *outer_obstack, tree decl)
{
  struct c_expr ret;
  struct obstack braced_init_obstack;
  location_t brace_loc = c_parser_peek_token (parser)->location;
  gcc_obstack_init (&braced_init_obstack);
  gcc_assert (c_parser_next_token_is (parser, CPP_OPEN_BRACE));
  bool save_c_omp_array_section_p = c_omp_array_section_p;
  c_omp_array_section_p = false;
  matching_braces braces;
  braces.consume_open (parser);
  if (nested_p)
    {
      finish_implicit_inits (brace_loc, outer_obstack);
      push_init_level (brace_loc, 0, &braced_init_obstack);
    }
  else
    really_start_incremental_init (type);
  if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
    {
      pedwarn_c11 (brace_loc, OPT_Wpedantic,
                   "ISO C forbids empty initializer braces before C23");
    }
  else
    {
      if (decl && decl != error_mark_node && C_DECL_VARIABLE_SIZE (decl))
        error_at (brace_loc,
                  "variable-sized object may not be initialized except "
                  "with an empty initializer");
      /* Parse a non-empty initializer list, possibly with a trailing
         comma.  */
      while (true)
        {
          c_parser_initelt (parser, &braced_init_obstack);
          if (parser->error)
            break;
          if (c_parser_next_token_is (parser, CPP_COMMA))
            {
              last_init_list_comma = c_parser_peek_token (parser)->location;
              c_parser_consume_token (parser);
            }
          else
            break;
          if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
            break;
        }
    }
  c_omp_array_section_p = save_c_omp_array_section_p;
  c_token *next_tok = c_parser_peek_token (parser);
  if (next_tok->type != CPP_CLOSE_BRACE)
    {
      ret.set_error ();
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
      braces.skip_until_found_close (parser);
      pop_init_level (brace_loc, 0, &braced_init_obstack, last_init_list_comma);
      obstack_free (&braced_init_obstack, NULL);
      return ret;
    }
  location_t close_loc = next_tok->location;
  c_parser_consume_token (parser);
  ret = pop_init_level (brace_loc, 0, &braced_init_obstack, close_loc);
  obstack_free (&braced_init_obstack, NULL);
  set_c_expr_source_range (&ret, brace_loc, close_loc);
  return ret;
}

/* Parse a nested initializer, including designators.  */

static void
c_parser_initelt (c_parser *parser, struct obstack * braced_init_obstack)
{
  /* Parse any designator or designator list.  A single array
     designator may have the subsequent "=" omitted in GNU C, but a
     longer list or a structure member designator may not.  */
  if (c_parser_next_token_is (parser, CPP_NAME)
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    {
      /* Old-style structure member designator.  */
      set_init_label (c_parser_peek_token (parser)->location,
                      c_parser_peek_token (parser)->value,
                      c_parser_peek_token (parser)->location,
                      braced_init_obstack);
      /* Use the colon as the error location.  */
      pedwarn (c_parser_peek_2nd_token (parser)->location, OPT_Wpedantic,
               "obsolete use of designated initializer with %<:%>");
      c_parser_consume_token (parser);
      c_parser_consume_token (parser);
    }
  else
    {
      /* des_seen is 0 if there have been no designators, 1 if there
         has been a single array designator and 2 otherwise.  */
      int des_seen = 0;
      /* Location of a designator.  */
      location_t des_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
      while (c_parser_next_token_is (parser, CPP_OPEN_SQUARE)
             || c_parser_next_token_is (parser, CPP_DOT))
        {
          int des_prev = des_seen;
          if (!des_seen)
            des_loc = c_parser_peek_token (parser)->location;
          if (des_seen < 2)
            des_seen++;
          if (c_parser_next_token_is (parser, CPP_DOT))
            {
              des_seen = 2;
              c_parser_consume_token (parser);
              if (c_parser_next_token_is (parser, CPP_NAME))
                {
                  set_init_label (des_loc, c_parser_peek_token (parser)->value,
                                  c_parser_peek_token (parser)->location,
                                  braced_init_obstack);
                  c_parser_consume_token (parser);
                }
              else
                {
                  struct c_expr init;
                  init.set_error ();
                  init.original_code = ERROR_MARK;
                  init.original_type = NULL;
                  c_parser_error (parser, "expected identifier");
                  c_parser_skip_until_found (parser, CPP_COMMA, NULL);
                  process_init_element (input_location, init, false,
                                        braced_init_obstack);
                  return;
                }
            }
          else
            {
              struct c_expr first_expr;
              tree first, second;
              location_t ellipsis_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
              location_t array_index_loc = UNKNOWN_LOCATION;
              /* ??? Following the old parser, [ objc-receiver
                 objc-message-args ] is accepted as an initializer,
                 being distinguished from a designator by what follows
                 the first assignment expression inside the square
                 brackets, but after a first array designator a
                 subsequent square bracket is for Objective-C taken to
                 start an expression, using the obsolete form of
                 designated initializer without '=', rather than
                 possibly being a second level of designation: in LALR
                 terms, the '[' is shifted rather than reducing
                 designator to designator-list.  */
              if (des_prev == 1 && c_dialect_objc ())
                {
                  des_seen = des_prev;
                  break;
                }
              if (des_prev == 0 && c_dialect_objc ())
                {
                  /* This might be an array designator or an
                     Objective-C message expression.  If the former,
                     continue parsing here; if the latter, parse the
                     remainder of the initializer given the starting
                     primary-expression.  ??? It might make sense to
                     distinguish when des_prev == 1 as well; see
                     previous comment.  */
                  tree rec, args;
                  struct c_expr mexpr;
                  c_parser_consume_token (parser);
                  if (c_parser_peek_token (parser)->type == CPP_NAME
                      && ((c_parser_peek_token (parser)->id_kind
                           == C_ID_TYPENAME)
                          || (c_parser_peek_token (parser)->id_kind
                              == C_ID_CLASSNAME)))
                    {
                      /* Type name receiver.  */
                      tree id = c_parser_peek_token (parser)->value;
                      c_parser_consume_token (parser);
                      rec = objc_get_class_reference (id);
                      goto parse_message_args;
                    }
                  array_index_loc = c_parser_peek_token (parser)->location;
                  first_expr = c_parser_expr_no_commas (parser, NULL);
                  mark_exp_read (first_expr.value);
                  if (c_parser_next_token_is (parser, CPP_ELLIPSIS)
                      || c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
                    goto array_desig_after_first;
                  first = first_expr.value;
                  /* Expression receiver.  So far only one part
                     without commas has been parsed; there might be
                     more of the expression.  */
                  rec = first;
                  while (c_parser_next_token_is (parser, CPP_COMMA))
                    {
                      struct c_expr next;
                      location_t comma_loc, exp_loc;
                      comma_loc = c_parser_peek_token (parser)->location;
                      c_parser_consume_token (parser);
                      exp_loc = c_parser_peek_token (parser)->location;
                      next = c_parser_expr_no_commas (parser, NULL);
                      next = convert_lvalue_to_rvalue (exp_loc, next,
                                                       true, true);
                      rec = build_compound_expr (comma_loc, rec, next.value);
                    }
                parse_message_args:
                  /* Now parse the objc-message-args.  */
                  args = c_parser_objc_message_args (parser);
                  c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                             "expected %<]%>");
                  mexpr.value
                    = objc_build_message_expr (rec, args);
                  mexpr.original_code = ERROR_MARK;
                  mexpr.original_type = NULL;
                  mexpr.m_decimal = 0;
                  /* Now parse and process the remainder of the
                     initializer, starting with this message
                     expression as a primary-expression.  */
                  c_parser_initval (parser, &mexpr, braced_init_obstack);
                  return;
                }
              c_parser_consume_token (parser);
              array_index_loc = c_parser_peek_token (parser)->location;
              first_expr = c_parser_expr_no_commas (parser, NULL);
              mark_exp_read (first_expr.value);
            array_desig_after_first:
              first_expr = convert_lvalue_to_rvalue (array_index_loc,
                                                     first_expr,
                                                     true, true);
              first = first_expr.value;
              if (c_parser_next_token_is (parser, CPP_ELLIPSIS))
                {
                  ellipsis_loc = c_parser_peek_token (parser)->location;
                  c_parser_consume_token (parser);
                  second = convert_lvalue_to_rvalue (ellipsis_loc,
                                                     (c_parser_expr_no_commas
                                                      (parser, NULL)),
                                                     true, true).value;
                  mark_exp_read (second);
                }
              else
                second = NULL_TREE;
              if (c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
                {
                  c_parser_consume_token (parser);
                  set_init_index (array_index_loc, first, second,
                                  braced_init_obstack);
                  if (second)
                    pedwarn (ellipsis_loc, OPT_Wpedantic,
                             "ISO C forbids specifying range of elements to initialize");
                }
              else
                c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                           "expected %<]%>");
            }
        }
      if (des_seen >= 1)
        {
          if (c_parser_next_token_is (parser, CPP_EQ))
            {
              pedwarn_c90 (des_loc, OPT_Wpedantic,
                           "ISO C90 forbids specifying subobject "
                           "to initialize");
              c_parser_consume_token (parser);
            }
          else
            {
              if (des_seen == 1)
                pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
                         "obsolete use of designated initializer without %<=%>");
              else
                {
                  struct c_expr init;
                  init.set_error ();
                  init.original_code = ERROR_MARK;
                  init.original_type = NULL;
                  c_parser_error (parser, "expected %<=%>");
                  c_parser_skip_until_found (parser, CPP_COMMA, NULL);
                  process_init_element (input_location, init, false,
                                        braced_init_obstack);
                  return;
                }
            }
        }
    }
  c_parser_initval (parser, NULL, braced_init_obstack);
}

/* Parse a nested initializer; as c_parser_initializer but parses
   initializers within braced lists, after any designators have been
   applied.  If AFTER is not NULL then it is an Objective-C message
   expression which is the primary-expression starting the
   initializer.  */

static void
c_parser_initval (c_parser *parser, struct c_expr *after,
                  struct obstack * braced_init_obstack)
{
  struct c_expr init;
  gcc_assert (!after || c_dialect_objc ());
  location_t loc = c_parser_peek_token (parser)->location;

  if (c_parser_next_token_is (parser, CPP_OPEN_BRACE) && !after)
    init = c_parser_braced_init (parser, NULL_TREE, true,
                                 braced_init_obstack, NULL_TREE);
  else
    {
      init = c_parser_expr_no_commas (parser, after);
      if (init.value != NULL_TREE
          && TREE_CODE (init.value) != STRING_CST
          && (TREE_CODE (init.value) != COMPOUND_LITERAL_EXPR
              || C_DECL_DECLARED_CONSTEXPR (COMPOUND_LITERAL_EXPR_DECL
                                            (init.value))))
        init = convert_lvalue_to_rvalue (loc, init, true, true, true);
    }
  process_init_element (loc, init, false, braced_init_obstack);
}

/* Parse a compound statement (possibly a function body) (C90 6.6.2,
   C99 6.8.2, C11 6.8.2, C23 6.8.2).

   compound-statement:
     { block-item-list[opt] }
     { label-declarations block-item-list }

   block-item-list:
     block-item
     block-item-list block-item

   block-item:
     label
     nested-declaration
     statement

   nested-declaration:
     declaration

   GNU extensions:

   compound-statement:
     { label-declarations block-item-list }

   nested-declaration:
     __extension__ nested-declaration
     nested-function-definition

   label-declarations:
     label-declaration
     label-declarations label-declaration

   label-declaration:
     __label__ identifier-list ;

   Allowing the mixing of declarations and code is new in C99.  The
   GNU syntax also permits (not shown above) labels at the end of
   compound statements, which yield an error.  We don't allow labels
   on declarations; this might seem like a natural extension, but
   there would be a conflict between gnu-attributes on the label and
   prefix gnu-attributes on the declaration.  ??? The syntax follows the
   old parser in requiring something after label declarations.
   Although they are erroneous if the labels declared aren't defined,
   is it useful for the syntax to be this way?

   OpenACC:

   block-item:
     openacc-directive

   openacc-directive:
     update-directive

   OpenMP:

   block-item:
     openmp-directive

   openmp-directive:
     barrier-directive
     flush-directive
     taskwait-directive
     taskyield-directive
     cancel-directive
     cancellation-point-directive  */

static tree
c_parser_compound_statement (c_parser *parser, location_t *endlocp)
{
  tree stmt;
  location_t brace_loc;
  brace_loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
    {
      /* Ensure a scope is entered and left anyway to avoid confusion
         if we have just prepared to enter a function body.  */
      stmt = c_begin_compound_stmt (true);
      c_end_compound_stmt (brace_loc, stmt, true);
      return error_mark_node;
    }
  stmt = c_begin_compound_stmt (true);
  location_t end_loc = c_parser_compound_statement_nostart (parser);
  if (endlocp)
    *endlocp = end_loc;

  return c_end_compound_stmt (brace_loc, stmt, true);
}

/* Diagnose errors related to imperfectly nested loops in an OMP
   loop construct.  This function is called when such code is seen.
   Only issue one such diagnostic no matter how much invalid
   intervening code there is in the loop.
   FIXME: maybe the location associated with the diagnostic should
   be the current parser token instead of the location of the outer loop
   nest.  */

static void
check_omp_intervening_code (c_parser *parser)
{
  struct omp_for_parse_data *omp_for_parse_state = parser->omp_for_parse_state;
  gcc_assert (omp_for_parse_state);

  if (!omp_for_parse_state->in_intervening_code)
    return;
  omp_for_parse_state->saw_intervening_code = true;

  /* Only diagnose errors related to perfect nesting once.  */
  if (!omp_for_parse_state->perfect_nesting_fail)
    {

      /* OpenACC does not (yet) permit intervening code, in
         addition to situations forbidden by the OpenMP spec.  */
      if (omp_for_parse_state->code == OACC_LOOP)
        {
          error_at (omp_for_parse_state->for_loc,
                    "inner loops must be perfectly nested in "
                    "%<#pragma acc loop%>");
          omp_for_parse_state->perfect_nesting_fail = true;
        }
      else if (omp_for_parse_state->ordered)
        {
          error_at (omp_for_parse_state->for_loc,
                    "inner loops must be perfectly nested with "
                    "%<ordered%> clause");
          omp_for_parse_state->perfect_nesting_fail = true;
        }
      else if (omp_for_parse_state->inscan)
        {
          error_at (omp_for_parse_state->for_loc,
                    "inner loops must be perfectly nested with "
                    "%<reduction%> %<inscan%> clause");
          omp_for_parse_state->perfect_nesting_fail = true;
        }
      /* TODO: Also reject loops with TILE directive.  */
      if (omp_for_parse_state->perfect_nesting_fail)
        omp_for_parse_state->fail = true;
    }
}

/* Helper function for below:  wrap an OMP_STRUCTURED_BLOCK around SL
   and add the statement to the current list.  If SL is an empty statement
   list, do nothing.  */
static void
add_structured_block_stmt (tree sl)
{
  if (TREE_CODE (sl) != STATEMENT_LIST
      || !tsi_end_p (tsi_start (sl)))
    add_stmt (build1 (OMP_STRUCTURED_BLOCK, void_type_node, sl));
}

struct c_omp_attribute_data
{
  vec<c_token, va_gc> *tokens;
  const c_omp_directive *dir;
  c_omp_directive_kind kind;
};

/* Handle omp::directive and omp::sequence attributes in ATTRS
   (if any) at the start of a statement or in attribute-declaration.  */

static bool
c_parser_handle_statement_omp_attributes (c_parser *parser, tree &attrs,
                                          bool *have_std_attrs)
{
  if (!flag_openmp && !flag_openmp_simd)
    return false;

  auto_vec<c_omp_attribute_data, 16> vd;
  int cnt = 0;
  int tokens = 0;
  bool bad = false;
  for (tree *pa = &attrs; *pa; )
    if (is_attribute_namespace_p ("omp", *pa)
        && is_attribute_p ("directive", get_attribute_name (*pa)))
      {
        cnt++;
        for (tree a = TREE_VALUE (*pa); a; a = TREE_CHAIN (a))
          {
            tree d = TREE_VALUE (a);
            gcc_assert (TREE_CODE (d) == C_TOKEN_VEC);
            vec<c_token, va_gc> *toks = C_TOKEN_VEC_TOKENS (d);
            c_token *first = toks->address ();
            c_token *last = first + toks->length ();
            if (parser->omp_attrs_forbidden_p)
              {
                error_at (first->location,
                          "mixing OpenMP directives with attribute and pragma "
                          "syntax on the same statement");
                parser->omp_attrs_forbidden_p = false;
                bad = true;
              }
            else if (TREE_PUBLIC (d))
              {
                error_at (first->location,
                          "OpenMP %<omp::decl%> attribute on a statement");
                bad = true;
              }
            const char *directive[3] = {};
            for (int i = 0; i < 3; i++)
              {
                tree id = NULL_TREE;
                if (first + i == last)
                  break;
                if (first[i].type == CPP_NAME)
                  id = first[i].value;
                else if (first[i].type == CPP_KEYWORD)
                  id = ridpointers[(int) first[i].keyword];
                else
                  break;
                directive[i] = IDENTIFIER_POINTER (id);
              }
            const c_omp_directive *dir = NULL;
            if (directive[0])
              dir = c_omp_categorize_directive (directive[0], directive[1],
                                                directive[2]);
            if (dir == NULL)
              {
                error_at (first->location,
                          "unknown OpenMP directive name in %qs attribute "
                          "argument",
                          TREE_PUBLIC (d) ? "omp::decl" : "omp::directive");
                continue;
              }
            c_omp_directive_kind kind = dir->kind;
            if (dir->id == PRAGMA_OMP_ORDERED)
              {
                /* ordered is C_OMP_DIR_CONSTRUCT only if it doesn't contain
                   depend/doacross clause.  */
                if (directive[1]
                    && (strcmp (directive[1], "depend") == 0
                        || strcmp (directive[1], "doacross") == 0))
                  kind = C_OMP_DIR_STANDALONE;
                else if (first + 2 < last
                         && first[1].type == CPP_COMMA
                         && first[2].type == CPP_NAME
                         && (strcmp (IDENTIFIER_POINTER (first[2].value),
                                     "depend") == 0
                             || strcmp (IDENTIFIER_POINTER (first[2].value),
                                        "doacross") == 0))
                  kind = C_OMP_DIR_STANDALONE;
              }
            else if (dir->id == PRAGMA_OMP_ERROR)
              {
                /* error with at(execution) clause is C_OMP_DIR_STANDALONE.  */
                int paren_depth = 0;
                for (int i = 1; first + i < last; i++)
                  if (first[i].type == CPP_OPEN_PAREN)
                    paren_depth++;
                  else if (first[i].type == CPP_CLOSE_PAREN)
                    paren_depth--;
                  else if (paren_depth == 0
                           && first + i + 2 < last
                           && first[i].type == CPP_NAME
                           && first[i + 1].type == CPP_OPEN_PAREN
                           && first[i + 2].type == CPP_NAME
                           && !strcmp (IDENTIFIER_POINTER (first[i].value),
                                       "at")
                           && !strcmp (IDENTIFIER_POINTER (first[i
                                                                 + 2].value),
                                       "execution"))
                    {
                      kind = C_OMP_DIR_STANDALONE;
                      break;
                    }
              }
            c_omp_attribute_data v = { toks, dir, kind };
            vd.safe_push (v);
            if (flag_openmp || dir->simd)
              tokens += (last - first) + 1;
          }
        c_omp_attribute_data v = {};
        vd.safe_push (v);
        *pa = TREE_CHAIN (*pa);
      }
    else
      pa = &TREE_CHAIN (*pa);

  if (bad)
    {
    fail:
      if (have_std_attrs && attrs == NULL)
        *have_std_attrs = false;
      return false;
    }

  unsigned int i;
  c_omp_attribute_data *v;
  c_omp_attribute_data *construct_seen = nullptr;
  c_omp_attribute_data *standalone_seen = nullptr;
  c_omp_attribute_data *prev_standalone_seen = nullptr;
  FOR_EACH_VEC_ELT (vd, i, v)
    if (v->tokens)
      {
        if (v->kind == C_OMP_DIR_CONSTRUCT && !construct_seen)
          construct_seen = v;
        else if (v->kind == C_OMP_DIR_STANDALONE && !standalone_seen)
          standalone_seen = v;
      }
    else
      {
        if (standalone_seen && !prev_standalone_seen)
          {
            prev_standalone_seen = standalone_seen;
            standalone_seen = nullptr;
          }
      }

  if (cnt > 1 && construct_seen)
    {
      error_at ((*construct_seen->tokens)[0].location,
                "OpenMP construct among %<omp::directive%> attributes"
                " requires all %<omp::directive%> attributes on the"
                " same statement to be in the same %<omp::sequence%>");
      goto fail;
    }
  if (cnt > 1 && standalone_seen && prev_standalone_seen)
    {
      error_at ((*standalone_seen->tokens)[0].location,
                "multiple OpenMP standalone directives among"
                " %<omp::directive%> attributes must be all within the"
                " same %<omp::sequence%>");
      goto fail;
    }

  if (prev_standalone_seen)
    standalone_seen = prev_standalone_seen;
  if (standalone_seen
      && !c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      error_at (standalone_seen->tokens->address ()->location,
                "standalone OpenMP directives in %<omp::directive%> attribute"
                " can only appear on an empty statement");
      goto fail;
    }
  if (cnt && c_parser_next_token_is (parser, CPP_PRAGMA))
    {
      c_token *token = c_parser_peek_token (parser);
      enum pragma_kind kind = token->pragma_kind;
      if (kind >= PRAGMA_OMP__START_ && kind <= PRAGMA_OMP__LAST_)
        {
          error_at (token->location,
                    "mixing OpenMP directives with attribute and pragma "
                    "syntax on the same statement");
          goto fail;
        }
    }

  if (!tokens)
    return false;

  unsigned int tokens_avail = parser->tokens_avail;
  gcc_assert (parser->tokens == &parser->tokens_buf[0]);

  tokens++;
  vec<c_token, va_gc> *toks = NULL;
  vec_safe_reserve (toks, tokens, true);
  FOR_EACH_VEC_ELT (vd, i, v)
    {
      if (!v->tokens)
        continue;
      if (!flag_openmp && !v->dir->simd)
        continue;
      c_token *first = v->tokens->address ();
      c_token *last = first + v->tokens->length ();
      c_token tok = {};
      tok.type = CPP_PRAGMA;
      tok.keyword = RID_MAX;
      tok.pragma_kind = pragma_kind (v->dir->id);
      tok.location = first->location;
      toks->quick_push (tok);
      while (++first < last)
        toks->quick_push (*first);
      tok = {};
      tok.type = CPP_PRAGMA_EOL;
      tok.keyword = RID_MAX;
      tok.location = last[-1].location;
      toks->quick_push (tok);
    }

  c_token tok = {};
  tok.type = CPP_EOF;
  tok.keyword = RID_MAX;
  tok.location = toks->last ().location;
  tok.flags = tokens_avail;
  toks->quick_push (tok);

  parser->tokens = toks->address ();
  parser->tokens_avail = tokens;
  parser->in_omp_attribute_pragma = toks;
  return true;
}

/* Handle omp::directive and omp::sequence attributes in ATTRS
   (if any) at the start or after declaration-id of a declaration.  */

static void
c_parser_handle_directive_omp_attributes (tree &attrs,
                                          vec<c_token> *&pragma_clauses,
                                          vec<c_token> *attr_clauses)
{
  if (!flag_openmp && !flag_openmp_simd)
    return;

  for (tree *pa = &attrs; *pa; )
    if (is_attribute_namespace_p ("omp", *pa)
        && is_attribute_p ("directive", get_attribute_name (*pa)))
      {
        int cnt = 0;
        for (tree *pa2 = &TREE_VALUE (*pa); *pa2; )
          {
            tree a = *pa2;
            tree d = TREE_VALUE (a);
            gcc_assert (TREE_CODE (d) == C_TOKEN_VEC);
            vec<c_token, va_gc> *toks = C_TOKEN_VEC_TOKENS (d);
            c_token *first = toks->address ();
            c_token *last = first + toks->length ();
            const char *directive[3] = {};
            for (int i = 0; i < 3; i++)
              {
                tree id = NULL_TREE;
                if (first + i == last)
                  break;
                if (first[i].type == CPP_NAME)
                  id = first[i].value;
                else if (first[i].type == CPP_KEYWORD)
                  id = ridpointers[(int) first[i].keyword];
                else
                  break;
                directive[i] = IDENTIFIER_POINTER (id);
              }
            const c_omp_directive *dir = NULL;
            if (directive[0])
              dir = c_omp_categorize_directive (directive[0], directive[1],
                                                directive[2]);
            if (dir == NULL)
              {
                error_at (first->location,
                          "unknown OpenMP directive name in "
                          "%qs attribute argument",
                          TREE_PUBLIC (d) ? "omp::decl" : "omp::directive");
                *pa2 = TREE_CHAIN (a);
              }
            else if (dir->id == PRAGMA_OMP_DECLARE
                     && (strcmp (directive[1], "simd") == 0
                         || strcmp (directive[1], "variant") == 0))
              {
                if (pragma_clauses)
                  {
                    error_at (first->location,
                              "mixing OpenMP directives with attribute and "
                              "pragma syntax on the same declaration");
                    for (pa = &attrs; *pa; )
                      if (is_attribute_namespace_p ("omp", *pa)
                          && is_attribute_p ("directive",
                                             get_attribute_name (*pa)))
                        *pa = TREE_CHAIN (*pa);
                      else
                        pa = &TREE_CHAIN (*pa);
                    return;
                  }
                ++cnt;
                attr_clauses->reserve (attr_clauses->length ()
                                       + toks->length () + 2);
                for (++first; first < last; ++first)
                  attr_clauses->quick_push (*first);
                c_token tok = {};
                tok.type = CPP_PRAGMA_EOL;
                tok.keyword = RID_MAX;
                tok.location = last[-1].location;
                attr_clauses->quick_push (tok);
                *pa2 = TREE_CHAIN (a);
              }
            else
              pa2 = &TREE_CHAIN (a);
          }
        if (cnt && TREE_VALUE (*pa) == NULL_TREE)
          *pa = TREE_CHAIN (*pa);
        else
          pa = &TREE_CHAIN (*pa);
      }
    else
      pa = &TREE_CHAIN (*pa);
  if (attr_clauses->length ())
    {
      c_token tok = {};
      tok.type = CPP_EOF;
      tok.keyword = RID_MAX;
      tok.location = attr_clauses->last ().location;
      attr_clauses->quick_push (tok);
      attr_clauses->quick_push (tok);
      pragma_clauses = attr_clauses;
    }
}

/* Parse a compound statement except for the opening brace.  This is
   used for parsing both compound statements and statement expressions
   (which follow different paths to handling the opening).  */

static location_t
c_parser_compound_statement_nostart (c_parser *parser)
{
  bool last_stmt = false;
  bool last_label = false;
  bool save_valid_for_pragma = valid_location_for_stdc_pragma_p ();
  location_t label_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
  struct omp_for_parse_data *omp_for_parse_state
    = parser->omp_for_parse_state;
  bool in_omp_loop_block
    = omp_for_parse_state ? omp_for_parse_state->want_nested_loop : false;
  tree sl = NULL_TREE;

  if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
    {
      location_t endloc = c_parser_peek_token (parser)->location;
      add_debug_begin_stmt (endloc);
      c_parser_consume_token (parser);
      return endloc;
    }

  /* If we're parsing a {} sequence in an OMP_FOR body, start a
     statement list for intervening code.  */
  if (in_omp_loop_block)
    sl = push_stmt_list ();

  mark_valid_location_for_stdc_pragma (true);
  if (c_parser_next_token_is_keyword (parser, RID_LABEL))
    {
      /* Read zero or more forward-declarations for labels that nested
         functions can jump to.  */
      mark_valid_location_for_stdc_pragma (false);
      if (in_omp_loop_block)
        check_omp_intervening_code (parser);
      while (c_parser_next_token_is_keyword (parser, RID_LABEL))
        {
          label_loc = c_parser_peek_token (parser)->location;
          c_parser_consume_token (parser);
          /* Any identifiers, including those declared as type names,
             are OK here.  */
          while (true)
            {
              tree label;
              if (c_parser_next_token_is_not (parser, CPP_NAME))
                {
                  c_parser_error (parser, "expected identifier");
                  break;
                }
              label
                = declare_label (c_parser_peek_token (parser)->value);
              C_DECLARED_LABEL_FLAG (label) = 1;
              add_stmt (build_stmt (label_loc, DECL_EXPR, label));
              c_parser_consume_token (parser);
              if (c_parser_next_token_is (parser, CPP_COMMA))
                c_parser_consume_token (parser);
              else
                break;
            }
          c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
        }
      pedwarn (label_loc, OPT_Wpedantic, "ISO C forbids label declarations");
    }
  /* We must now have at least one statement, label or declaration.  */
  if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
    {
      mark_valid_location_for_stdc_pragma (save_valid_for_pragma);
      c_parser_error (parser, "expected declaration or statement");
      location_t endloc = c_parser_peek_token (parser)->location;
      c_parser_consume_token (parser);
      return endloc;
    }
  while (c_parser_next_token_is_not (parser, CPP_CLOSE_BRACE))
    {
      location_t loc = c_parser_peek_token (parser)->location;
      loc = expansion_point_location_if_in_system_header (loc);

      bool want_nested_loop = (omp_for_parse_state
                               ? omp_for_parse_state->want_nested_loop
                               : false);

      /* First take care of special cases for OpenMP "canonical loop
         nest form", that do not allow standard attributes, labels, or
         __extension__ before the nested statement.  */
      if (in_omp_loop_block && !last_label)
        {
          if (want_nested_loop
              && c_parser_next_token_is_keyword (parser, RID_FOR))
            {
              /* Found the next nested loop.  If there were intervening
                 code statements collected before now, wrap them in an
                 OMP_STRUCTURED_BLOCK node, and start a new structured
                 block to hold statements that may come after the FOR.  */
              gcc_assert (sl);
              add_structured_block_stmt (pop_stmt_list (sl));
              omp_for_parse_state->depth++;
              add_stmt (c_parser_omp_loop_nest (parser, NULL));
              omp_for_parse_state->depth--;
              sl = push_stmt_list ();
              parser->error = false;
              continue;
            }
          else if (want_nested_loop
                   && c_parser_next_token_is (parser, CPP_OPEN_BRACE))
            {
              /* If this nested compound statement contains the nested loop,
                 we need to separate the other statements in the current
                 statement into separate blocks of intervening code.  If
                 there's no nested loop, it's all part of the same
                 chunk of intervening code.  */
              tree pre_sl = pop_stmt_list (sl);
              tree nested_sl = push_stmt_list ();
              mark_valid_location_for_stdc_pragma (false);
              c_parser_statement_after_labels (parser, NULL);
              nested_sl = pop_stmt_list (nested_sl);
              if (omp_for_parse_state->want_nested_loop)
                {
                  /* This block didn't contain a loop-nest, so it's
                     all part of the same chunk of intervening code.  */
                  check_omp_intervening_code (parser);
                  sl = push_stmt_list ();
                  add_stmt (pre_sl);
                  add_stmt (nested_sl);
                }
              else
                {
                  /* It contains the nested loop.  */
                  add_structured_block_stmt (pre_sl);
                  add_stmt (nested_sl);
                  sl = push_stmt_list ();
                }
              parser->error = false;
              continue;
            }
          else if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              /* Prior to implementing the OpenMP 5.1 syntax for canonical
                 loop form, GCC used to accept an empty statements that
                 would now be flagged as intervening code.  Continue to
                 do that, as an extension.  */
              /* FIXME:  Maybe issue a warning or something here?  */
              c_parser_consume_token (parser);
              continue;
            }
        }

      /* Standard attributes may start a label, statement or declaration.  */
      bool have_std_attrs
        = c_parser_nth_token_starts_std_attributes (parser, 1);
      tree std_attrs = NULL_TREE;
      if (have_std_attrs)
        std_attrs = c_parser_std_attribute_specifier_sequence (parser);
      if (c_parser_next_token_is_keyword (parser, RID_CASE)
          || c_parser_next_token_is_keyword (parser, RID_DEFAULT)
          || (c_parser_next_token_is (parser, CPP_NAME)
              && c_parser_peek_2nd_token (parser)->type == CPP_COLON))
        {
          if (c_parser_next_token_is_keyword (parser, RID_CASE))
            label_loc = c_parser_peek_2nd_token (parser)->location;
          else
            label_loc = c_parser_peek_token (parser)->location;
          last_label = true;
          last_stmt = false;
          mark_valid_location_for_stdc_pragma (false);
          if (in_omp_loop_block)
            check_omp_intervening_code (parser);
          c_parser_label (parser, std_attrs);
        }
      else if (c_parser_next_tokens_start_declaration (parser)
               || (have_std_attrs
                   && !c_parser_handle_statement_omp_attributes
                                (parser, std_attrs, &have_std_attrs)
                   && c_parser_next_token_is (parser, CPP_SEMICOLON)
                   && (have_std_attrs = true)))
        {
          if (last_label)
            pedwarn_c11 (c_parser_peek_token (parser)->location, OPT_Wpedantic,
                         "a label can only be part of a statement and "
                         "a declaration is not a statement");
          /* It's unlikely we'll see a nested loop in a declaration in
             intervening code in an OMP loop, but disallow it anyway.  */
          if (in_omp_loop_block)
            {
              check_omp_intervening_code (parser);
              omp_for_parse_state->want_nested_loop = false;
            }
          mark_valid_location_for_stdc_pragma (false);
          bool fallthru_attr_p = false;
          c_parser_declaration_or_fndef (parser, true, !have_std_attrs,
                                         true, true, true, NULL,
                                         NULL, have_std_attrs, std_attrs,
                                         NULL, &fallthru_attr_p);

          if (in_omp_loop_block)
              omp_for_parse_state->want_nested_loop = want_nested_loop;
          if (last_stmt && !fallthru_attr_p)
            pedwarn_c90 (loc, OPT_Wdeclaration_after_statement,
                         "ISO C90 forbids mixed declarations and code");
          last_stmt = fallthru_attr_p;
          last_label = false;
        }
      else if (c_parser_next_token_is_keyword (parser, RID_EXTENSION))
        {
          /* __extension__ can start a declaration, but is also an
             unary operator that can start an expression.  Consume all
             but the last of a possible series of __extension__ to
             determine which.  If standard attributes have already
             been seen, it must start a statement, not a declaration,
             but standard attributes starting a declaration may appear
             after __extension__.  */
          while (c_parser_peek_2nd_token (parser)->type == CPP_KEYWORD
                 && (c_parser_peek_2nd_token (parser)->keyword
                     == RID_EXTENSION))
            c_parser_consume_token (parser);
          if (!have_std_attrs
              && (c_token_starts_declaration (c_parser_peek_2nd_token (parser))
                  || c_parser_nth_token_starts_std_attributes (parser, 2)))
            {
              int ext;
              ext = disable_extension_diagnostics ();
              c_parser_consume_token (parser);
              last_label = false;
              /* It's unlikely we'll see a nested loop in a declaration in
                 intervening code in an OMP loop, but disallow it anyway.  */
              if (in_omp_loop_block)
                {
                  check_omp_intervening_code (parser);
                  omp_for_parse_state->want_nested_loop = false;
                }
              mark_valid_location_for_stdc_pragma (false);
              c_parser_declaration_or_fndef (parser, true, true, true, true,
                                             true);
              if (in_omp_loop_block)
                omp_for_parse_state->want_nested_loop = want_nested_loop;
              /* Following the old parser, __extension__ does not
                 disable this diagnostic.  */
              restore_extension_diagnostics (ext);
              if (last_stmt)
                pedwarn_c90 (loc, OPT_Wdeclaration_after_statement,
                             "ISO C90 forbids mixed declarations and code");
              last_stmt = false;
            }
          else
            goto statement;
        }
      else if (c_parser_next_token_is (parser, CPP_PRAGMA))
        {
          if (have_std_attrs && !parser->in_omp_attribute_pragma)
            c_parser_error (parser, "expected declaration or statement");
          else if (std_attrs)
            c_warn_unused_attributes (std_attrs);
          /* External pragmas, and some omp pragmas, are not associated
             with regular c code, and so are not to be considered statements
             syntactically.  This ensures that the user doesn't put them
             places that would turn into syntax errors if the directive
             were ignored.  */
          if (omp_for_parse_state)
            omp_for_parse_state->want_nested_loop = false;
          if (c_parser_pragma (parser,
                               last_label ? pragma_stmt : pragma_compound,
                               NULL))
            {
              last_label = false;
              last_stmt = true;
              if (omp_for_parse_state)
                check_omp_intervening_code (parser);
            }
          if (omp_for_parse_state)
            omp_for_parse_state->want_nested_loop = want_nested_loop;
        }
      else if (c_parser_next_token_is (parser, CPP_EOF))
        {
          mark_valid_location_for_stdc_pragma (save_valid_for_pragma);
          c_parser_error (parser, "expected declaration or statement");
          return c_parser_peek_token (parser)->location;
        }
      else if (c_parser_next_token_is_keyword (parser, RID_ELSE))
        {
          if (parser->in_if_block)
            {
              mark_valid_location_for_stdc_pragma (save_valid_for_pragma);
              error_at (loc, "expected %<}%> before %<else%>");
              return c_parser_peek_token (parser)->location;
            }
          else
            {
              error_at (loc, "%<else%> without a previous %<if%>");
              c_parser_consume_token (parser);
              continue;
            }
        }
      else
        {
        statement:
          c_warn_unused_attributes (std_attrs);
          last_label = false;
          last_stmt = true;
          mark_valid_location_for_stdc_pragma (false);
          if (!omp_for_parse_state)
            c_parser_statement_after_labels (parser, NULL);
          else
            {
              /* In canonical loop nest form, nested loops can only appear
                 directly, or in a directly nested compound statement.  We
                 already took care of those cases above, so now we have
                 something else.  This statement and everything inside
                 it must be intervening code.  */
              omp_for_parse_state->want_nested_loop = false;
              check_omp_intervening_code (parser);
              c_parser_statement_after_labels (parser, NULL);
              omp_for_parse_state->want_nested_loop = want_nested_loop;
            }
        }

      parser->error = false;
    }
  if (last_label)
    pedwarn_c11 (label_loc, OPT_Wpedantic, "label at end of compound statement");
  location_t endloc = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);

  /* Restore the value we started with.  */
  mark_valid_location_for_stdc_pragma (save_valid_for_pragma);

  /* Package leftover intervening code, or the whole contents of the
     compound statement if we were looking for a nested loop in an OMP_FOR
     construct and didn't find one.  */
  if (sl)
    {
      sl = pop_stmt_list (sl);
      if (omp_for_parse_state->want_nested_loop)
        add_stmt (sl);
      else
        add_structured_block_stmt (sl);
    }
  return endloc;
}

/* Parse all consecutive labels, possibly preceded by standard
   attributes.  In this context, a statement is required, not a
   declaration, so attributes must be followed by a statement that is
   not just a semicolon.  */

static void
c_parser_all_labels (c_parser *parser)
{
  bool have_std_attrs;
  tree std_attrs = NULL;
  if ((have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1)))
    std_attrs = c_parser_std_attribute_specifier_sequence (parser);
  while (c_parser_next_token_is_keyword (parser, RID_CASE)
         || c_parser_next_token_is_keyword (parser, RID_DEFAULT)
         || (c_parser_next_token_is (parser, CPP_NAME)
             && c_parser_peek_2nd_token (parser)->type == CPP_COLON))
    {
      c_parser_label (parser, std_attrs);
      std_attrs = NULL;
      if ((have_std_attrs = c_parser_nth_token_starts_std_attributes (parser,
                                                                      1)))
        std_attrs = c_parser_std_attribute_specifier_sequence (parser);
    }
  if (std_attrs
      && (!c_parser_handle_statement_omp_attributes (parser, std_attrs, &have_std_attrs)
          || std_attrs))
    {
      if (have_std_attrs && c_parser_next_token_is (parser, CPP_SEMICOLON))
        c_parser_error (parser, "expected statement");
      c_warn_unused_attributes (std_attrs);
    }
  else if (have_std_attrs && c_parser_next_token_is (parser, CPP_SEMICOLON))
    c_parser_error (parser, "expected statement");
}

/* Parse a label (C90 6.6.1, C99 6.8.1, C11 6.8.1).

   label:
     identifier : gnu-attributes[opt]
     case constant-expression :
     default :

   GNU extensions:

   label:
     case constant-expression ... constant-expression :

   The use of gnu-attributes on labels is a GNU extension.  The syntax in
   GNU C accepts any expressions without commas, non-constant
   expressions being rejected later.  Any standard
   attribute-specifier-sequence before the first label has been parsed
   in the caller, to distinguish statements from declarations.  Any
   attribute-specifier-sequence after the label is parsed in this
   function.  */
static void
c_parser_label (c_parser *parser, tree std_attrs)
{
  location_t loc1 = c_parser_peek_token (parser)->location;
  tree label = NULL_TREE;

  /* Remember whether this case or a user-defined label is allowed to fall
     through to.  */
  bool fallthrough_p = c_parser_peek_token (parser)->flags & PREV_FALLTHROUGH;

  if (c_parser_next_token_is_keyword (parser, RID_CASE))
    {
      tree exp1, exp2;
      c_parser_consume_token (parser);
      exp1 = convert_lvalue_to_rvalue (loc1,
                                       c_parser_expr_no_commas (parser, NULL),
                                       true, true).value;
      if (c_parser_next_token_is (parser, CPP_COLON))
        {
          c_parser_consume_token (parser);
          label = do_case (loc1, exp1, NULL_TREE, std_attrs);
        }
      else if (c_parser_next_token_is (parser, CPP_ELLIPSIS))
        {
          c_parser_consume_token (parser);
          exp2 = convert_lvalue_to_rvalue (loc1,
                                           c_parser_expr_no_commas (parser,
                                                                    NULL),
                                           true, true).value;
          if (c_parser_require (parser, CPP_COLON, "expected %<:%>"))
            label = do_case (loc1, exp1, exp2, std_attrs);
        }
      else
        c_parser_error (parser, "expected %<:%> or %<...%>");
    }
  else if (c_parser_next_token_is_keyword (parser, RID_DEFAULT))
    {
      c_parser_consume_token (parser);
      if (c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        label = do_case (loc1, NULL_TREE, NULL_TREE, std_attrs);
    }
  else
    {
      tree name = c_parser_peek_token (parser)->value;
      tree tlab;
      tree attrs;
      location_t loc2 = c_parser_peek_token (parser)->location;
      gcc_assert (c_parser_next_token_is (parser, CPP_NAME));
      c_parser_consume_token (parser);
      gcc_assert (c_parser_next_token_is (parser, CPP_COLON));
      c_parser_consume_token (parser);
      attrs = c_parser_gnu_attributes (parser);
      tlab = define_label (loc2, name);
      if (tlab)
        {
          decl_attributes (&tlab, attrs, 0);
          decl_attributes (&tlab, std_attrs, 0);
          label = add_stmt (build_stmt (loc1, LABEL_EXPR, tlab));
        }
      if (attrs
          && c_parser_next_tokens_start_declaration (parser))
          warning_at (loc2, OPT_Wattributes, "GNU-style attribute between"
                      " label and declaration appertains to the label");
    }
  if (label)
    {
      if (TREE_CODE (label) == LABEL_EXPR)
        FALLTHROUGH_LABEL_P (LABEL_EXPR_LABEL (label)) = fallthrough_p;
      else
        FALLTHROUGH_LABEL_P (CASE_LABEL (label)) = fallthrough_p;
    }
}

/* Parse a statement (C90 6.6, C99 6.8, C11 6.8).

   statement:
     labeled-statement
     attribute-specifier-sequence[opt] compound-statement
     expression-statement
     attribute-specifier-sequence[opt] selection-statement
     attribute-specifier-sequence[opt] iteration-statement
     attribute-specifier-sequence[opt] jump-statement

   labeled-statement:
     attribute-specifier-sequence[opt] label statement

   expression-statement:
     expression[opt] ;
     attribute-specifier-sequence expression ;

   selection-statement:
     if-statement
     switch-statement

   iteration-statement:
     while-statement
     do-statement
     for-statement

   jump-statement:
     goto identifier ;
     continue ;
     break ;
     return expression[opt] ;

   GNU extensions:

   statement:
     attribute-specifier-sequence[opt] asm-statement

   jump-statement:
     goto * expression ;

   expression-statement:
     gnu-attributes ;

   Objective-C:

   statement:
     attribute-specifier-sequence[opt] objc-throw-statement
     attribute-specifier-sequence[opt] objc-try-catch-statement
     attribute-specifier-sequence[opt] objc-synchronized-statement

   objc-throw-statement:
     @throw expression ;
     @throw ;

   OpenACC:

   statement:
     attribute-specifier-sequence[opt] openacc-construct

   openacc-construct:
     parallel-construct
     kernels-construct
     data-construct
     loop-construct

   parallel-construct:
     parallel-directive structured-block

   kernels-construct:
     kernels-directive structured-block

   data-construct:
     data-directive structured-block

   loop-construct:
     loop-directive structured-block

   OpenMP:

   statement:
     attribute-specifier-sequence[opt] openmp-construct

   openmp-construct:
     parallel-construct
     for-construct
     simd-construct
     for-simd-construct
     sections-construct
     single-construct
     parallel-for-construct
     parallel-for-simd-construct
     parallel-sections-construct
     master-construct
     critical-construct
     atomic-construct
     ordered-construct

   parallel-construct:
     parallel-directive structured-block

   for-construct:
     for-directive iteration-statement

   simd-construct:
     simd-directive iteration-statements

   for-simd-construct:
     for-simd-directive iteration-statements

   sections-construct:
     sections-directive section-scope

   single-construct:
     single-directive structured-block

   parallel-for-construct:
     parallel-for-directive iteration-statement

   parallel-for-simd-construct:
     parallel-for-simd-directive iteration-statement

   parallel-sections-construct:
     parallel-sections-directive section-scope

   master-construct:
     master-directive structured-block

   critical-construct:
     critical-directive structured-block

   atomic-construct:
     atomic-directive expression-statement

   ordered-construct:
     ordered-directive structured-block

   Transactional Memory:

   statement:
     attribute-specifier-sequence[opt] transaction-statement
     attribute-specifier-sequence[opt] transaction-cancel-statement

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static void
c_parser_statement (c_parser *parser, bool *if_p, location_t *loc_after_labels)
{
  c_parser_all_labels (parser);
  if (loc_after_labels)
    *loc_after_labels = c_parser_peek_token (parser)->location;
  parser->omp_attrs_forbidden_p = false;
  c_parser_statement_after_labels (parser, if_p, NULL);
}

/* Parse a statement, other than a labeled statement.  CHAIN is a vector
   of if-else-if conditions.  All labels and standard attributes have
   been parsed in the caller.

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static void
c_parser_statement_after_labels (c_parser *parser, bool *if_p,
                                 vec<tree> *chain)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree stmt = NULL_TREE;
  bool in_if_block = parser->in_if_block;
  parser->in_if_block = false;
  if (if_p != NULL)
    *if_p = false;

  if (c_parser_peek_token (parser)->type != CPP_OPEN_BRACE)
    add_debug_begin_stmt (loc);

 restart:
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_OPEN_BRACE:
      add_stmt (c_parser_compound_statement (parser));
      break;
    case CPP_KEYWORD:
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_IF:
          c_parser_if_statement (parser, if_p, chain);
          break;
        case RID_SWITCH:
          c_parser_switch_statement (parser, if_p);
          break;
        case RID_WHILE:
          c_parser_while_statement (parser, false, 0, false, if_p);
          break;
        case RID_DO:
          c_parser_do_statement (parser, false, 0, false);
          break;
        case RID_FOR:
          c_parser_for_statement (parser, false, 0, false, if_p);
          break;
        case RID_GOTO:
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_NAME))
            {
              stmt = c_finish_goto_label (loc,
                                          c_parser_peek_token (parser)->value);
              c_parser_consume_token (parser);
            }
          else if (c_parser_next_token_is (parser, CPP_MULT))
            {
              struct c_expr val;

              c_parser_consume_token (parser);
              val = c_parser_expression (parser);
              val = convert_lvalue_to_rvalue (loc, val, false, true);
              stmt = c_finish_goto_ptr (loc, val);
            }
          else
            c_parser_error (parser, "expected identifier or %<*%>");
          goto expect_semicolon;
        case RID_CONTINUE:
          c_parser_consume_token (parser);
          stmt = c_finish_bc_stmt (loc, objc_foreach_continue_label, false);
          goto expect_semicolon;
        case RID_BREAK:
          c_parser_consume_token (parser);
          stmt = c_finish_bc_stmt (loc, objc_foreach_break_label, true);
          goto expect_semicolon;
        case RID_RETURN:
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              stmt = c_finish_return (loc, NULL_TREE, NULL_TREE);
              c_parser_consume_token (parser);
            }
          else
            {
              location_t xloc = c_parser_peek_token (parser)->location;
              struct c_expr expr = c_parser_expression_conv (parser);
              mark_exp_read (expr.value);
              stmt = c_finish_return (EXPR_LOC_OR_LOC (expr.value, xloc),
                                      expr.value, expr.original_type);
              goto expect_semicolon;
            }
          break;
        case RID_ASM:
          stmt = c_parser_asm_statement (parser);
          break;
        case RID_TRANSACTION_ATOMIC:
        case RID_TRANSACTION_RELAXED:
          stmt = c_parser_transaction (parser,
              c_parser_peek_token (parser)->keyword);
          break;
        case RID_TRANSACTION_CANCEL:
          stmt = c_parser_transaction_cancel (parser);
          goto expect_semicolon;
        case RID_AT_THROW:
          gcc_assert (c_dialect_objc ());
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              stmt = objc_build_throw_stmt (loc, NULL_TREE);
              c_parser_consume_token (parser);
            }
          else
            {
              struct c_expr expr = c_parser_expression (parser);
              expr = convert_lvalue_to_rvalue (loc, expr, false, false);
              expr.value = c_fully_fold (expr.value, false, NULL);
              stmt = objc_build_throw_stmt (loc, expr.value);
              goto expect_semicolon;
            }
          break;
        case RID_AT_TRY:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_try_catch_finally_statement (parser);
          break;
        case RID_AT_SYNCHRONIZED:
          gcc_assert (c_dialect_objc ());
          c_parser_objc_synchronized_statement (parser);
          break;
        case RID_ATTRIBUTE:
          {
            /* Allow '__attribute__((fallthrough));' or
               '__attribute__((assume(cond)));'.  */
            tree attrs = c_parser_gnu_attributes (parser);
            bool has_assume = lookup_attribute ("assume", attrs);
            if (has_assume)
              {
                if (c_parser_next_token_is (parser, CPP_SEMICOLON))
                  attrs = handle_assume_attribute (loc, attrs, true);
                else
                  {
                    warning_at (loc, OPT_Wattributes,
                                "%<assume%> attribute not followed by %<;%>");
                    has_assume = false;
                  }
              }
            if (attribute_fallthrough_p (attrs))
              {
                if (c_parser_next_token_is (parser, CPP_SEMICOLON))
                  {
                    tree fn = build_call_expr_internal_loc (loc,
                                                            IFN_FALLTHROUGH,
                                                            void_type_node, 0);
                    add_stmt (fn);
                    /* Eat the ';'.  */
                    c_parser_consume_token (parser);
                  }
                else
                  warning_at (loc, OPT_Wattributes,
                              "%<fallthrough%> attribute not followed "
                              "by %<;%>");
              }
            else if (has_assume)
              /* Eat the ';'.  */
              c_parser_consume_token (parser);
            else if (attrs != NULL_TREE)
              warning_at (loc, OPT_Wattributes,
                          "only attribute %<fallthrough%> or %<assume%> can "
                          "be applied to a null statement");
            break;
          }
        default:
          goto expr_stmt;
        }
      break;
    case CPP_SEMICOLON:
      c_parser_consume_token (parser);
      break;
    case CPP_CLOSE_PAREN:
    case CPP_CLOSE_SQUARE:
      /* Avoid infinite loop in error recovery:
         c_parser_skip_until_found stops at a closing nesting
         delimiter without consuming it, but here we need to consume
         it to proceed further.  */
      c_parser_error (parser, "expected statement");
      c_parser_consume_token (parser);
      break;
    case CPP_PRAGMA:
      if (!c_parser_pragma (parser, pragma_stmt, if_p))
        goto restart;
      break;
    default:
    expr_stmt:
      stmt = c_finish_expr_stmt (loc, c_parser_expression_conv (parser).value);
    expect_semicolon:
      c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
      break;
    }
  /* Two cases cannot and do not have line numbers associated: If stmt
     is degenerate, such as "2;", then stmt is an INTEGER_CST, which
     cannot hold line numbers.  But that's OK because the statement
     will either be changed to a MODIFY_EXPR during gimplification of
     the statement expr, or discarded.  If stmt was compound, but
     without new variables, we will have skipped the creation of a
     BIND and will have a bare STATEMENT_LIST.  But that's OK because
     (recursively) all of the component statements should already have
     line numbers assigned.  ??? Can we discard no-op statements
     earlier?  */
  if (EXPR_LOCATION (stmt) == UNKNOWN_LOCATION)
    protected_set_expr_location (stmt, loc);

  parser->in_if_block = in_if_block;
}

/* Parse the condition from an if, do, while or for statements.  */

static tree
c_parser_condition (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree cond;
  cond = c_parser_expression_conv (parser).value;
  cond = c_objc_common_truthvalue_conversion (loc, cond);
  cond = c_fully_fold (cond, false, NULL);
  if (warn_sequence_point)
    verify_sequence_points (cond);
  return cond;
}

/* Parse a parenthesized condition from an if, do or while statement.

   condition:
     ( expression )
*/
static tree
c_parser_paren_condition (c_parser *parser)
{
  tree cond;
  matching_parens parens;
  if (!parens.require_open (parser))
    return error_mark_node;
  cond = c_parser_condition (parser);
  parens.skip_until_found_close (parser);
  return cond;
}

/* Parse a statement which is a block in C99.

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static tree
c_parser_c99_block_statement (c_parser *parser, bool *if_p,
                              location_t *loc_after_labels)
{
  tree block = c_begin_compound_stmt (flag_isoc99);
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_statement (parser, if_p, loc_after_labels);
  return c_end_compound_stmt (loc, block, flag_isoc99);
}

/* Parse the body of an if statement.  This is just parsing a
   statement but (a) it is a block in C99, (b) we track whether the
   body is an if statement for the sake of -Wparentheses warnings, (c)
   we handle an empty body specially for the sake of -Wempty-body
   warnings, and (d) we call parser_compound_statement directly
   because c_parser_statement_after_labels resets
   parser->in_if_block.

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static tree
c_parser_if_body (c_parser *parser, bool *if_p,
                  const token_indent_info &if_tinfo)
{
  tree block = c_begin_compound_stmt (flag_isoc99);
  location_t body_loc = c_parser_peek_token (parser)->location;
  location_t body_loc_after_labels = UNKNOWN_LOCATION;
  token_indent_info body_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));

  c_parser_all_labels (parser);
  if (c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      location_t loc = c_parser_peek_token (parser)->location;
      add_stmt (build_empty_stmt (loc));
      c_parser_consume_token (parser);
      if (!c_parser_next_token_is_keyword (parser, RID_ELSE))
        warning_at (loc, OPT_Wempty_body,
                    "suggest braces around empty body in an %<if%> statement");
    }
  else if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    add_stmt (c_parser_compound_statement (parser));
  else
    {
      body_loc_after_labels = c_parser_peek_token (parser)->location;
      c_parser_statement_after_labels (parser, if_p);
    }

  token_indent_info next_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  warn_for_misleading_indentation (if_tinfo, body_tinfo, next_tinfo);
  if (body_loc_after_labels != UNKNOWN_LOCATION
      && next_tinfo.type != CPP_SEMICOLON)
    warn_for_multistatement_macros (body_loc_after_labels, next_tinfo.location,
                                    if_tinfo.location, RID_IF);

  return c_end_compound_stmt (body_loc, block, flag_isoc99);
}

/* Parse the else body of an if statement.  This is just parsing a
   statement but (a) it is a block in C99, (b) we handle an empty body
   specially for the sake of -Wempty-body warnings.  CHAIN is a vector
   of if-else-if conditions.  */

static tree
c_parser_else_body (c_parser *parser, const token_indent_info &else_tinfo,
                    vec<tree> *chain)
{
  location_t body_loc = c_parser_peek_token (parser)->location;
  tree block = c_begin_compound_stmt (flag_isoc99);
  token_indent_info body_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  location_t body_loc_after_labels = UNKNOWN_LOCATION;

  c_parser_all_labels (parser);
  if (c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      location_t loc = c_parser_peek_token (parser)->location;
      warning_at (loc,
                  OPT_Wempty_body,
                 "suggest braces around empty body in an %<else%> statement");
      add_stmt (build_empty_stmt (loc));
      c_parser_consume_token (parser);
    }
  else
    {
      if (!c_parser_next_token_is (parser, CPP_OPEN_BRACE))
        body_loc_after_labels = c_parser_peek_token (parser)->location;
      c_parser_statement_after_labels (parser, NULL, chain);
    }

  token_indent_info next_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  warn_for_misleading_indentation (else_tinfo, body_tinfo, next_tinfo);
  if (body_loc_after_labels != UNKNOWN_LOCATION
      && next_tinfo.type != CPP_SEMICOLON)
    warn_for_multistatement_macros (body_loc_after_labels, next_tinfo.location,
                                    else_tinfo.location, RID_ELSE);

  return c_end_compound_stmt (body_loc, block, flag_isoc99);
}

/* We might need to reclassify any previously-lexed identifier, e.g.
   when we've left a for loop with an if-statement without else in the
   body - we might have used a wrong scope for the token.  See PR67784.  */

static void
c_parser_maybe_reclassify_token (c_parser *parser)
{
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      c_token *token = c_parser_peek_token (parser);

      if (token->id_kind != C_ID_CLASSNAME)
        {
          tree decl = lookup_name (token->value);

          token->id_kind = C_ID_ID;
          if (decl)
            {
              if (TREE_CODE (decl) == TYPE_DECL)
                token->id_kind = C_ID_TYPENAME;
            }
          else if (c_dialect_objc ())
            {
              tree objc_interface_decl = objc_is_class_name (token->value);
              /* Objective-C class names are in the same namespace as
                 variables and typedefs, and hence are shadowed by local
                 declarations.  */
              if (objc_interface_decl)
                {
                  token->value = objc_interface_decl;
                  token->id_kind = C_ID_CLASSNAME;
                }
            }
        }
    }
}

/* Parse an if statement (C90 6.6.4, C99 6.8.4, C11 6.8.4).

   if-statement:
     if ( expression ) statement
     if ( expression ) statement else statement

   CHAIN is a vector of if-else-if conditions.
   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static void
c_parser_if_statement (c_parser *parser, bool *if_p, vec<tree> *chain)
{
  tree block;
  location_t loc;
  tree cond;
  bool nested_if = false;
  tree first_body, second_body;
  bool in_if_block;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_IF));
  token_indent_info if_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  c_parser_consume_token (parser);
  block = c_begin_compound_stmt (flag_isoc99);
  loc = c_parser_peek_token (parser)->location;
  cond = c_parser_paren_condition (parser);
  in_if_block = parser->in_if_block;
  parser->in_if_block = true;
  first_body = c_parser_if_body (parser, &nested_if, if_tinfo);
  parser->in_if_block = in_if_block;

  if (warn_duplicated_cond)
    warn_duplicated_cond_add_or_warn (EXPR_LOCATION (cond), cond, &chain);

  if (c_parser_next_token_is_keyword (parser, RID_ELSE))
    {
      token_indent_info else_tinfo
        = get_token_indent_info (c_parser_peek_token (parser));
      c_parser_consume_token (parser);
      if (warn_duplicated_cond)
        {
          if (c_parser_next_token_is_keyword (parser, RID_IF)
              && chain == NULL)
            {
              /* We've got "if (COND) else if (COND2)".  Start the
                 condition chain and add COND as the first element.  */
              chain = new vec<tree> ();
              if (!CONSTANT_CLASS_P (cond) && !TREE_SIDE_EFFECTS (cond))
                chain->safe_push (cond);
            }
          else if (!c_parser_next_token_is_keyword (parser, RID_IF))
            /* This is if-else without subsequent if.  Zap the condition
               chain; we would have already warned at this point.  */
            vec_free (chain);
        }
      second_body = c_parser_else_body (parser, else_tinfo, chain);
      /* Set IF_P to true to indicate that this if statement has an
         else clause.  This may trigger the Wparentheses warning
         below when we get back up to the parent if statement.  */
      if (if_p != NULL)
        *if_p = true;
    }
  else
    {
      second_body = NULL_TREE;

      /* Diagnose an ambiguous else if if-then-else is nested inside
         if-then.  */
      if (nested_if)
        warning_at (loc, OPT_Wdangling_else,
                    "suggest explicit braces to avoid ambiguous %<else%>");

      if (warn_duplicated_cond)
        /* This if statement does not have an else clause.  We don't
           need the condition chain anymore.  */
        vec_free (chain);
    }
  c_finish_if_stmt (loc, cond, first_body, second_body);
  add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));

  c_parser_maybe_reclassify_token (parser);
}

/* Parse a switch statement (C90 6.6.4, C99 6.8.4, C11 6.8.4).

   switch-statement:
     switch (expression) statement
*/

static void
c_parser_switch_statement (c_parser *parser, bool *if_p)
{
  struct c_expr ce;
  tree block, expr, body;
  unsigned char save_in_statement;
  location_t switch_loc = c_parser_peek_token (parser)->location;
  location_t switch_cond_loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_SWITCH));
  c_parser_consume_token (parser);
  block = c_begin_compound_stmt (flag_isoc99);
  bool explicit_cast_p = false;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      switch_cond_loc = c_parser_peek_token (parser)->location;
      if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)
          && c_token_starts_typename (c_parser_peek_2nd_token (parser)))
        explicit_cast_p = true;
      ce = c_parser_expression (parser);
      ce = convert_lvalue_to_rvalue (switch_cond_loc, ce, true, true);
      expr = ce.value;
      /* ??? expr has no valid location?  */
      parens.skip_until_found_close (parser);
    }
  else
    {
      switch_cond_loc = UNKNOWN_LOCATION;
      expr = error_mark_node;
      ce.original_type = error_mark_node;
    }
  c_start_switch (switch_loc, switch_cond_loc, expr, explicit_cast_p);
  save_in_statement = in_statement;
  in_statement |= IN_SWITCH_STMT;
  location_t loc_after_labels;
  bool open_brace_p = c_parser_peek_token (parser)->type == CPP_OPEN_BRACE;
  body = c_parser_c99_block_statement (parser, if_p, &loc_after_labels);
  location_t next_loc = c_parser_peek_token (parser)->location;
  if (!open_brace_p && c_parser_peek_token (parser)->type != CPP_SEMICOLON)
    warn_for_multistatement_macros (loc_after_labels, next_loc, switch_loc,
                                    RID_SWITCH);
  c_finish_switch (body, ce.original_type);
  in_statement = save_in_statement;
  add_stmt (c_end_compound_stmt (switch_loc, block, flag_isoc99));
  c_parser_maybe_reclassify_token (parser);
}

/* Parse a while statement (C90 6.6.5, C99 6.8.5, C11 6.8.5).

   while-statement:
      while (expression) statement

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static void
c_parser_while_statement (c_parser *parser, bool ivdep, unsigned short unroll,
                          bool novector, bool *if_p)
{
  tree block, cond, body;
  unsigned char save_in_statement;
  location_t loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_WHILE));
  token_indent_info while_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));

  if (parser->omp_for_parse_state)
    {
      error_at (c_parser_peek_token (parser)->location,
                "loop not permitted in intervening code in OpenMP loop body");
      parser->omp_for_parse_state->fail = true;
    }

  c_parser_consume_token (parser);
  block = c_begin_compound_stmt (flag_isoc99);
  loc = c_parser_peek_token (parser)->location;
  cond = c_parser_paren_condition (parser);
  if (ivdep && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_ivdep_kind),
                   integer_zero_node);
  if (unroll && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_unroll_kind),
                   build_int_cst (integer_type_node, unroll));
  if (novector && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_no_vector_kind),
                   integer_zero_node);
  save_in_statement = in_statement;
  in_statement = IN_ITERATION_STMT;

  token_indent_info body_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));

  location_t loc_after_labels;
  bool open_brace = c_parser_next_token_is (parser, CPP_OPEN_BRACE);
  body = c_parser_c99_block_statement (parser, if_p, &loc_after_labels);
  add_stmt (build_stmt (loc, WHILE_STMT, cond, body));
  add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));
  c_parser_maybe_reclassify_token (parser);

  token_indent_info next_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  warn_for_misleading_indentation (while_tinfo, body_tinfo, next_tinfo);

  if (next_tinfo.type != CPP_SEMICOLON && !open_brace)
    warn_for_multistatement_macros (loc_after_labels, next_tinfo.location,
                                    while_tinfo.location, RID_WHILE);

  in_statement = save_in_statement;
}

/* Parse a do statement (C90 6.6.5, C99 6.8.5, C11 6.8.5).

   do-statement:
     do statement while ( expression ) ;
*/

static void
c_parser_do_statement (c_parser *parser, bool ivdep, unsigned short unroll,
                       bool novector)
{
  tree block, cond, body;
  unsigned char save_in_statement;
  location_t loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_DO));

  if (parser->omp_for_parse_state)
    {
      error_at (c_parser_peek_token (parser)->location,
                "loop not permitted in intervening code in OpenMP loop body");
      parser->omp_for_parse_state->fail = true;
    }

  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_SEMICOLON))
    warning_at (c_parser_peek_token (parser)->location,
                OPT_Wempty_body,
                "suggest braces around empty body in %<do%> statement");
  block = c_begin_compound_stmt (flag_isoc99);
  loc = c_parser_peek_token (parser)->location;
  save_in_statement = in_statement;
  in_statement = IN_ITERATION_STMT;
  body = c_parser_c99_block_statement (parser, NULL);
  c_parser_require_keyword (parser, RID_WHILE, "expected %<while%>");
  in_statement = save_in_statement;
  cond = c_parser_paren_condition (parser);
  if (ivdep && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_ivdep_kind),
                   integer_zero_node);
  if (unroll && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_unroll_kind),
                   build_int_cst (integer_type_node, unroll));
  if (novector && cond != error_mark_node)
    cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                   build_int_cst (integer_type_node,
                                  annot_expr_no_vector_kind),
                   integer_zero_node);
  if (!c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
    c_parser_skip_to_end_of_block_or_statement (parser);

  add_stmt (build_stmt (loc, DO_STMT, cond, body));
  add_stmt (c_end_compound_stmt (loc, block, flag_isoc99));
}

/* Parse a for statement (C90 6.6.5, C99 6.8.5, C11 6.8.5).

   for-statement:
     for ( expression[opt] ; expression[opt] ; expression[opt] ) statement
     for ( nested-declaration expression[opt] ; expression[opt] ) statement

   The form with a declaration is new in C99.

   ??? In accordance with the old parser, the declaration may be a
   nested function, which is then rejected in check_for_loop_decls,
   but does it make any sense for this to be included in the grammar?
   Note in particular that the nested function does not include a
   trailing ';', whereas the "declaration" production includes one.
   Also, can we reject bad declarations earlier and cheaper than
   check_for_loop_decls?

   In Objective-C, there are two additional variants:

   foreach-statement:
     for ( expression in expresssion ) statement
     for ( declaration in expression ) statement

   This is inconsistent with C, because the second variant is allowed
   even if c99 is not enabled.

   The rest of the comment documents these Objective-C foreach-statement.

   Here is the canonical example of the first variant:
    for (object in array)    { do something with object }
   we call the first expression ("object") the "object_expression" and 
   the second expression ("array") the "collection_expression".
   object_expression must be an lvalue of type "id" (a generic Objective-C
   object) because the loop works by assigning to object_expression the
   various objects from the collection_expression.  collection_expression
   must evaluate to something of type "id" which responds to the method
   countByEnumeratingWithState:objects:count:.

   The canonical example of the second variant is:
    for (id object in array)    { do something with object }
   which is completely equivalent to
    {
      id object;
      for (object in array) { do something with object }
    }
   Note that initizializing 'object' in some way (eg, "for ((object =
   xxx) in array) { do something with object }") is possibly
   technically valid, but completely pointless as 'object' will be
   assigned to something else as soon as the loop starts.  We should
   most likely reject it (TODO).

   The beginning of the Objective-C foreach-statement looks exactly
   like the beginning of the for-statement, and we can tell it is a
   foreach-statement only because the initial declaration or
   expression is terminated by 'in' instead of ';'.

   IF_P is used to track whether there's a (possibly labeled) if statement
   which is not enclosed in braces and has an else clause.  This is used to
   implement -Wparentheses.  */

static void
c_parser_for_statement (c_parser *parser, bool ivdep, unsigned short unroll,
                        bool novector, bool *if_p)
{
  tree block, cond, incr, body;
  unsigned char save_in_statement;
  tree save_objc_foreach_break_label, save_objc_foreach_continue_label;
  /* The following are only used when parsing an ObjC foreach statement.  */
  tree object_expression;
  /* Silence the bogus uninitialized warning.  */
  tree collection_expression = NULL;
  location_t loc = c_parser_peek_token (parser)->location;
  location_t for_loc = loc;
  bool is_foreach_statement = false;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_FOR));
  token_indent_info for_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));

  if (parser->omp_for_parse_state)
    {
      error_at (for_loc,
                "loop not permitted in intervening code in OpenMP loop body");
      parser->omp_for_parse_state->fail = true;
    }

  c_parser_consume_token (parser);
  /* Open a compound statement in Objective-C as well, just in case this is
     as foreach expression.  */
  block = c_begin_compound_stmt (flag_isoc99 || c_dialect_objc ());
  cond = error_mark_node;
  incr = error_mark_node;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      /* Parse the initialization declaration or expression.  */
      object_expression = error_mark_node;
      parser->objc_could_be_foreach_context = c_dialect_objc ();
      if (c_parser_next_token_is (parser, CPP_SEMICOLON))
        {
          parser->objc_could_be_foreach_context = false;
          c_parser_consume_token (parser);
          c_finish_expr_stmt (loc, NULL_TREE);
        }
      else if (c_parser_next_tokens_start_declaration (parser)
               || c_parser_nth_token_starts_std_attributes (parser, 1))
        {
          c_parser_declaration_or_fndef (parser, true, true, true, true, true, 
                                         &object_expression);
          parser->objc_could_be_foreach_context = false;
          
          if (c_parser_next_token_is_keyword (parser, RID_IN))
            {
              c_parser_consume_token (parser);
              is_foreach_statement = true;
              if (check_for_loop_decls (for_loc, true) == NULL_TREE)
                c_parser_error (parser, "multiple iterating variables in "
                                        "fast enumeration");
            }
          else
            check_for_loop_decls (for_loc, flag_isoc99);
        }
      else if (c_parser_next_token_is_keyword (parser, RID_EXTENSION))
        {
          /* __extension__ can start a declaration, but is also an
             unary operator that can start an expression.  Consume all
             but the last of a possible series of __extension__ to
             determine which.  */
          while (c_parser_peek_2nd_token (parser)->type == CPP_KEYWORD
                 && (c_parser_peek_2nd_token (parser)->keyword
                     == RID_EXTENSION))
            c_parser_consume_token (parser);
          if (c_token_starts_declaration (c_parser_peek_2nd_token (parser))
              || c_parser_nth_token_starts_std_attributes (parser, 2))
            {
              int ext;
              ext = disable_extension_diagnostics ();
              c_parser_consume_token (parser);
              c_parser_declaration_or_fndef (parser, true, true, true, true,
                                             true, &object_expression);
              parser->objc_could_be_foreach_context = false;
              
              restore_extension_diagnostics (ext);
              if (c_parser_next_token_is_keyword (parser, RID_IN))
                {
                  c_parser_consume_token (parser);
                  is_foreach_statement = true;
                  if (check_for_loop_decls (for_loc, true) == NULL_TREE)
                    c_parser_error (parser, "multiple iterating variables in "
                                            "fast enumeration");
                }
              else
                check_for_loop_decls (for_loc, flag_isoc99);
            }
          else
            goto init_expr;
        }
      else
        {
        init_expr:
          {
            struct c_expr ce;
            tree init_expression;
            ce = c_parser_expression (parser);
            init_expression = ce.value;
            parser->objc_could_be_foreach_context = false;
            if (c_parser_next_token_is_keyword (parser, RID_IN))
              {
                c_parser_consume_token (parser);
                is_foreach_statement = true;
                if (! lvalue_p (init_expression))
                  c_parser_error (parser, "invalid iterating variable in "
                                          "fast enumeration");
                object_expression
                  = c_fully_fold (init_expression, false, NULL);
              }
            else
              {
                ce = convert_lvalue_to_rvalue (loc, ce, true, false);
                init_expression = ce.value;
                c_finish_expr_stmt (loc, init_expression);
                c_parser_skip_until_found (parser, CPP_SEMICOLON,
                                           "expected %<;%>");
              }
          }
        }
      /* Parse the loop condition.  In the case of a foreach
         statement, there is no loop condition.  */
      gcc_assert (!parser->objc_could_be_foreach_context);
      if (!is_foreach_statement)
        {
          if (c_parser_next_token_is (parser, CPP_SEMICOLON))
            {
              if (ivdep)
                {
                  c_parser_error (parser, "missing loop condition in loop "
                                          "with %<GCC ivdep%> pragma");
                  cond = error_mark_node;
                }
              else if (unroll)
                {
                  c_parser_error (parser, "missing loop condition in loop "
                                          "with %<GCC unroll%> pragma");
                  cond = error_mark_node;
                }
              else
                {
                  c_parser_consume_token (parser);
                  cond = NULL_TREE;
                }
            }
          else
            {
              cond = c_parser_condition (parser);
              c_parser_skip_until_found (parser, CPP_SEMICOLON,
                                         "expected %<;%>");
            }
          if (ivdep && cond != error_mark_node)
            cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                           build_int_cst (integer_type_node,
                                          annot_expr_ivdep_kind),
                           integer_zero_node);
          if (unroll && cond != error_mark_node)
            cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                           build_int_cst (integer_type_node,
                                          annot_expr_unroll_kind),
                           build_int_cst (integer_type_node, unroll));
          if (novector && cond && cond != error_mark_node)
            cond = build3 (ANNOTATE_EXPR, TREE_TYPE (cond), cond,
                           build_int_cst (integer_type_node,
                                          annot_expr_no_vector_kind),
                           integer_zero_node);
        }
      /* Parse the increment expression (the third expression in a
         for-statement).  In the case of a foreach-statement, this is
         the expression that follows the 'in'.  */
      loc = c_parser_peek_token (parser)->location;
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          if (is_foreach_statement)
            {
              c_parser_error (parser,
                              "missing collection in fast enumeration");
              collection_expression = error_mark_node;
            }
          else
            incr = c_process_expr_stmt (loc, NULL_TREE);
        }
      else
        {
          if (is_foreach_statement)
            collection_expression
              = c_fully_fold (c_parser_expression (parser).value, false, NULL);
          else
            {
              struct c_expr ce = c_parser_expression (parser);
              ce = convert_lvalue_to_rvalue (loc, ce, true, false);
              incr = c_process_expr_stmt (loc, ce.value);
            }
        }
      parens.skip_until_found_close (parser);
    }
  save_in_statement = in_statement;
  if (is_foreach_statement)
    {
      in_statement = IN_OBJC_FOREACH;
      save_objc_foreach_break_label = objc_foreach_break_label;
      save_objc_foreach_continue_label = objc_foreach_continue_label;
      objc_foreach_break_label = create_artificial_label (loc);
      objc_foreach_continue_label = create_artificial_label (loc);
    }
  else
    in_statement = IN_ITERATION_STMT;

  token_indent_info body_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));

  location_t loc_after_labels;
  bool open_brace = c_parser_next_token_is (parser, CPP_OPEN_BRACE);
  body = c_parser_c99_block_statement (parser, if_p, &loc_after_labels);

  if (is_foreach_statement)
    objc_finish_foreach_loop (for_loc, object_expression,
                              collection_expression, body,
                              objc_foreach_break_label,
                              objc_foreach_continue_label);
  else
    add_stmt (build_stmt (for_loc, FOR_STMT, NULL_TREE, cond, incr,
                          body, NULL_TREE));
  add_stmt (c_end_compound_stmt (for_loc, block,
                                 flag_isoc99 || c_dialect_objc ()));
  c_parser_maybe_reclassify_token (parser);

  token_indent_info next_tinfo
    = get_token_indent_info (c_parser_peek_token (parser));
  warn_for_misleading_indentation (for_tinfo, body_tinfo, next_tinfo);

  if (next_tinfo.type != CPP_SEMICOLON && !open_brace)
    warn_for_multistatement_macros (loc_after_labels, next_tinfo.location,
                                    for_tinfo.location, RID_FOR);

  in_statement = save_in_statement;
  if (is_foreach_statement)
    {
      objc_foreach_break_label = save_objc_foreach_break_label;
      objc_foreach_continue_label = save_objc_foreach_continue_label;
    }
}

/* Parse an asm statement, a GNU extension.  This is a full-blown asm
   statement with inputs, outputs, clobbers, and volatile, inline, and goto
   tags allowed.

   asm-qualifier:
     volatile
     inline
     goto

   asm-qualifier-list:
     asm-qualifier-list asm-qualifier
     asm-qualifier

   asm-statement:
     asm asm-qualifier-list[opt] ( asm-argument ) ;

   asm-argument:
     asm-string-literal
     asm-string-literal : asm-operands[opt]
     asm-string-literal : asm-operands[opt] : asm-operands[opt]
     asm-string-literal : asm-operands[opt] : asm-operands[opt] \
       : asm-clobbers[opt]
     asm-string-literal : : asm-operands[opt] : asm-clobbers[opt] \
       : asm-goto-operands

   The form with asm-goto-operands is valid if and only if the
   asm-qualifier-list contains goto, and is the only allowed form in that case.
   Duplicate asm-qualifiers are not allowed.

   The :: token is considered equivalent to two consecutive : tokens.  */

static tree
c_parser_asm_statement (c_parser *parser)
{
  tree str, outputs, inputs, clobbers, labels, ret;
  bool simple;
  location_t asm_loc = c_parser_peek_token (parser)->location;
  int section, nsections;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_ASM));
  c_parser_consume_token (parser);

  /* Handle the asm-qualifier-list.  */
  location_t volatile_loc = UNKNOWN_LOCATION;
  location_t inline_loc = UNKNOWN_LOCATION;
  location_t goto_loc = UNKNOWN_LOCATION;
  for (;;)
    {
      c_token *token = c_parser_peek_token (parser);
      location_t loc = token->location;
      switch (token->keyword)
        {
        case RID_VOLATILE:
          if (volatile_loc)
            {
              error_at (loc, "duplicate %<asm%> qualifier %qE", token->value);
              inform (volatile_loc, "first seen here");
            }
          else
            volatile_loc = loc;
          c_parser_consume_token (parser);
          continue;

        case RID_INLINE:
          if (inline_loc)
            {
              error_at (loc, "duplicate %<asm%> qualifier %qE", token->value);
              inform (inline_loc, "first seen here");
            }
          else
            inline_loc = loc;
          c_parser_consume_token (parser);
          continue;

        case RID_GOTO:
          if (goto_loc)
            {
              error_at (loc, "duplicate %<asm%> qualifier %qE", token->value);
              inform (goto_loc, "first seen here");
            }
          else
            goto_loc = loc;
          c_parser_consume_token (parser);
          continue;

        case RID_CONST:
        case RID_RESTRICT:
          error_at (loc, "%qE is not a valid %<asm%> qualifier", token->value);
          c_parser_consume_token (parser);
          continue;

        default:
          break;
        }
      break;
    }

  bool is_volatile = (volatile_loc != UNKNOWN_LOCATION);
  bool is_inline = (inline_loc != UNKNOWN_LOCATION);
  bool is_goto = (goto_loc != UNKNOWN_LOCATION);

  ret = NULL;

  matching_parens parens;
  if (!parens.require_open (parser))
    goto error;

  str = c_parser_asm_string_literal (parser);
  if (str == NULL_TREE)
    goto error_close_paren;

  simple = true;
  outputs = NULL_TREE;
  inputs = NULL_TREE;
  clobbers = NULL_TREE;
  labels = NULL_TREE;

  if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN) && !is_goto)
    goto done_asm;

  /* Parse each colon-delimited section of operands.  */
  nsections = 3 + is_goto;
  for (section = 0; section < nsections; ++section)
    {
      if (c_parser_next_token_is (parser, CPP_SCOPE))
        {
          ++section;
          if (section == nsections)
            {
              c_parser_error (parser, "expected %<)%>");
              goto error_close_paren;
            }
          c_parser_consume_token (parser);
        }
      else if (!c_parser_require (parser, CPP_COLON,
                                  is_goto
                                  ? G_("expected %<:%>")
                                  : G_("expected %<:%> or %<)%>"),
                                  UNKNOWN_LOCATION, is_goto))
        goto error_close_paren;

      /* Once past any colon, we're no longer a simple asm.  */
      simple = false;

      if ((!c_parser_next_token_is (parser, CPP_COLON)
           && !c_parser_next_token_is (parser, CPP_SCOPE)
           && !c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
          || section == 3)
        switch (section)
          {
          case 0:
            outputs = c_parser_asm_operands (parser);
            break;
          case 1:
            inputs = c_parser_asm_operands (parser);
            break;
          case 2:
            clobbers = c_parser_asm_clobbers (parser);
            break;
          case 3:
            labels = c_parser_asm_goto_operands (parser);
            break;
          default:
            gcc_unreachable ();
          }

      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN) && !is_goto)
        goto done_asm;
    }

 done_asm:
  if (!parens.require_close (parser))
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
      goto error;
    }

  if (!c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
    c_parser_skip_to_end_of_block_or_statement (parser);

  ret = build_asm_stmt (is_volatile,
                        build_asm_expr (asm_loc, str, outputs, inputs,
                                        clobbers, labels, simple, is_inline));

 error:
  return ret;

 error_close_paren:
  c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
  goto error;
}

/* Parse asm operands, a GNU extension.

   asm-operands:
     asm-operand
     asm-operands , asm-operand

   asm-operand:
     asm-string-literal ( expression )
     [ identifier ] asm-string-literal ( expression )
*/

static tree
c_parser_asm_operands (c_parser *parser)
{
  tree list = NULL_TREE;
  while (true)
    {
      tree name, str;
      struct c_expr expr;
      if (c_parser_next_token_is (parser, CPP_OPEN_SQUARE))
        {
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_NAME))
            {
              tree id = c_parser_peek_token (parser)->value;
              c_parser_consume_token (parser);
              name = build_string (IDENTIFIER_LENGTH (id),
                                   IDENTIFIER_POINTER (id));
            }
          else
            {
              c_parser_error (parser, "expected identifier");
              c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE, NULL);
              return NULL_TREE;
            }
          c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                     "expected %<]%>");
        }
      else
        name = NULL_TREE;
      str = c_parser_asm_string_literal (parser);
      if (str == NULL_TREE)
        return NULL_TREE;
      matching_parens parens;
      if (!parens.require_open (parser))
        return NULL_TREE;
      expr = c_parser_expression (parser);
      mark_exp_read (expr.value);
      if (!parens.require_close (parser))
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          return NULL_TREE;
        }
      list = chainon (list, build_tree_list (build_tree_list (name, str),
                                             expr.value));
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  return list;
}

/* Parse asm clobbers, a GNU extension.

   asm-clobbers:
     asm-string-literal
     asm-clobbers , asm-string-literal
*/

static tree
c_parser_asm_clobbers (c_parser *parser)
{
  tree list = NULL_TREE;
  while (true)
    {
      tree str = c_parser_asm_string_literal (parser);
      if (str)
        list = tree_cons (NULL_TREE, str, list);
      else
        return NULL_TREE;
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  return list;
}

/* Parse asm goto labels, a GNU extension.

   asm-goto-operands:
     identifier
     asm-goto-operands , identifier
*/

static tree
c_parser_asm_goto_operands (c_parser *parser)
{
  tree list = NULL_TREE;
  while (true)
    {
      tree name, label;

      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          c_token *tok = c_parser_peek_token (parser);
          name = tok->value;
          label = lookup_label_for_goto (tok->location, name);
          c_parser_consume_token (parser);
          TREE_USED (label) = 1;
        }
      else
        {
          c_parser_error (parser, "expected identifier");
          return NULL_TREE;
        }

      name = build_string (IDENTIFIER_LENGTH (name),
                           IDENTIFIER_POINTER (name));
      list = tree_cons (name, label, list);
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        return nreverse (list);
    }
}

/* Parse a possibly concatenated sequence of string literals.
   TRANSLATE says whether to translate them to the execution character
   set; WIDE_OK says whether any kind of prefixed string literal is
   permitted in this context.  This code is based on that in
   lex_string.  */

struct c_expr
c_parser_string_literal (c_parser *parser, bool translate, bool wide_ok)
{
  struct c_expr ret;
  size_t count;
  struct obstack str_ob;
  struct obstack loc_ob;
  cpp_string str, istr, *strs;
  c_token *tok;
  location_t loc, last_tok_loc;
  enum cpp_ttype type;
  tree value, string_tree;

  tok = c_parser_peek_token (parser);
  loc = tok->location;
  last_tok_loc = linemap_resolve_location (line_table, loc,
                                           LRK_MACRO_DEFINITION_LOCATION,
                                           NULL);
  type = tok->type;
  switch (type)
    {
    case CPP_STRING:
    case CPP_WSTRING:
    case CPP_STRING16:
    case CPP_STRING32:
    case CPP_UTF8STRING:
      string_tree = tok->value;
      break;

    default:
      c_parser_error (parser, "expected string literal");
      ret.set_error ();
      ret.value = NULL_TREE;
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL_TREE;
      return ret;
    }

  /* Try to avoid the overhead of creating and destroying an obstack
     for the common case of just one string.  */
  switch (c_parser_peek_2nd_token (parser)->type)
    {
    default:
      c_parser_consume_token (parser);
      str.text = (const unsigned char *) TREE_STRING_POINTER (string_tree);
      str.len = TREE_STRING_LENGTH (string_tree);
      count = 1;
      strs = &str;
      break;

    case CPP_STRING:
    case CPP_WSTRING:
    case CPP_STRING16:
    case CPP_STRING32:
    case CPP_UTF8STRING:
      gcc_obstack_init (&str_ob);
      gcc_obstack_init (&loc_ob);
      count = 0;
      do
        {
          c_parser_consume_token (parser);
          count++;
          str.text = (const unsigned char *) TREE_STRING_POINTER (string_tree);
          str.len = TREE_STRING_LENGTH (string_tree);
          if (type != tok->type)
            {
              if (type == CPP_STRING)
                type = tok->type;
              else if (tok->type != CPP_STRING)
                error ("unsupported non-standard concatenation "
                       "of string literals");
            }
          obstack_grow (&str_ob, &str, sizeof (cpp_string));
          obstack_grow (&loc_ob, &last_tok_loc, sizeof (location_t));
          tok = c_parser_peek_token (parser);
          string_tree = tok->value;
          last_tok_loc
            = linemap_resolve_location (line_table, tok->location,
                                        LRK_MACRO_DEFINITION_LOCATION, NULL);
        }
      while (tok->type == CPP_STRING
             || tok->type == CPP_WSTRING
             || tok->type == CPP_STRING16
             || tok->type == CPP_STRING32
             || tok->type == CPP_UTF8STRING);
      strs = (cpp_string *) obstack_finish (&str_ob);
    }

  if (count > 1 && !in_system_header_at (input_location))
    warning (OPT_Wtraditional,
             "traditional C rejects string constant concatenation");

  if ((type == CPP_STRING || wide_ok)
      && ((translate
          ? cpp_interpret_string : cpp_interpret_string_notranslate)
          (parse_in, strs, count, &istr, type)))
    {
      value = build_string (istr.len, (const char *) istr.text);
      free (CONST_CAST (unsigned char *, istr.text));
      if (count > 1)
        {
          location_t *locs = (location_t *) obstack_finish (&loc_ob);
          gcc_assert (g_string_concat_db);
          g_string_concat_db->record_string_concatenation (count, locs);
        }
    }
  else
    {
      if (type != CPP_STRING && !wide_ok)
        {
          error_at (loc, "a wide string is invalid in this context");
          type = CPP_STRING;
        }
      /* Callers cannot generally handle error_mark_node in this
         context, so return the empty string instead.  An error has
         been issued, either above or from cpp_interpret_string.  */
      switch (type)
        {
        default:
        case CPP_STRING:
        case CPP_UTF8STRING:
          if (type == CPP_UTF8STRING && flag_char8_t)
            {
              value = build_string (TYPE_PRECISION (char8_type_node)
                                    / TYPE_PRECISION (char_type_node),
                                    "");  /* char8_t is 8 bits */
            }
          else
            value = build_string (1, "");
          break;
        case CPP_STRING16:
          value = build_string (TYPE_PRECISION (char16_type_node)
                                / TYPE_PRECISION (char_type_node),
                                "\0");  /* char16_t is 16 bits */
          break;
        case CPP_STRING32:
          value = build_string (TYPE_PRECISION (char32_type_node)
                                / TYPE_PRECISION (char_type_node),
                                "\0\0\0");  /* char32_t is 32 bits */
          break;
        case CPP_WSTRING:
          value = build_string (TYPE_PRECISION (wchar_type_node)
                                / TYPE_PRECISION (char_type_node),
                                "\0\0\0");  /* widest supported wchar_t
                                               is 32 bits */
          break;
        }
    }

  switch (type)
    {
    default:
    case CPP_STRING:
      TREE_TYPE (value) = char_array_type_node;
      break;
    case CPP_UTF8STRING:
      if (flag_char8_t)
        TREE_TYPE (value) = char8_array_type_node;
      else
        TREE_TYPE (value) = char_array_type_node;
      break;
    case CPP_STRING16:
      TREE_TYPE (value) = char16_array_type_node;
      break;
    case CPP_STRING32:
      TREE_TYPE (value) = char32_array_type_node;
      break;
    case CPP_WSTRING:
      TREE_TYPE (value) = wchar_array_type_node;
    }
  value = fix_string_type (value);

  if (count > 1)
    {
      obstack_free (&str_ob, 0);
      obstack_free (&loc_ob, 0);
    }

  ret.value = value;
  ret.original_code = STRING_CST;
  ret.original_type = NULL_TREE;
  set_c_expr_source_range (&ret, get_range_from_loc (line_table, loc));
  ret.m_decimal = 0;
  parser->seen_string_literal = true;
  return ret;
}

/* Parse an expression other than a compound expression; that is, an
   assignment expression (C90 6.3.16, C99 6.5.16, C11 6.5.16).  If
   AFTER is not NULL then it is an Objective-C message expression which
   is the primary-expression starting the expression as an initializer.

   assignment-expression:
     conditional-expression
     unary-expression assignment-operator assignment-expression

   assignment-operator: one of
     = *= /= %= += -= <<= >>= &= ^= |=

   In GNU C we accept any conditional expression on the LHS and
   diagnose the invalid lvalue rather than producing a syntax
   error.  */

static struct c_expr
c_parser_expr_no_commas (c_parser *parser, struct c_expr *after,
                         tree omp_atomic_lhs)
{
  struct c_expr lhs, rhs, ret;
  enum tree_code code;
  location_t op_location, exp_location;
  bool save_in_omp_for = c_in_omp_for;
  c_in_omp_for = false;
  gcc_assert (!after || c_dialect_objc ());
  lhs = c_parser_conditional_expression (parser, after, omp_atomic_lhs);
  op_location = c_parser_peek_token (parser)->location;
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_EQ:
      code = NOP_EXPR;
      break;
    case CPP_MULT_EQ:
      code = MULT_EXPR;
      break;
    case CPP_DIV_EQ:
      code = TRUNC_DIV_EXPR;
      break;
    case CPP_MOD_EQ:
      code = TRUNC_MOD_EXPR;
      break;
    case CPP_PLUS_EQ:
      code = PLUS_EXPR;
      break;
    case CPP_MINUS_EQ:
      code = MINUS_EXPR;
      break;
    case CPP_LSHIFT_EQ:
      code = LSHIFT_EXPR;
      break;
    case CPP_RSHIFT_EQ:
      code = RSHIFT_EXPR;
      break;
    case CPP_AND_EQ:
      code = BIT_AND_EXPR;
      break;
    case CPP_XOR_EQ:
      code = BIT_XOR_EXPR;
      break;
    case CPP_OR_EQ:
      code = BIT_IOR_EXPR;
      break;
    default:
      c_in_omp_for = save_in_omp_for;
      return lhs;
    }
  c_parser_consume_token (parser);
  exp_location = c_parser_peek_token (parser)->location;
  rhs = c_parser_expr_no_commas (parser, NULL);
  rhs = convert_lvalue_to_rvalue (exp_location, rhs, true, true);
  
  ret.value = build_modify_expr (op_location, lhs.value, lhs.original_type,
                                 code, exp_location, rhs.value,
                                 rhs.original_type);
  ret.m_decimal = 0;
  set_c_expr_source_range (&ret, lhs.get_start (), rhs.get_finish ());
  if (code == NOP_EXPR)
    ret.original_code = MODIFY_EXPR;
  else
    {
      suppress_warning (ret.value, OPT_Wparentheses);
      ret.original_code = ERROR_MARK;
    }
  ret.original_type = NULL;
  c_in_omp_for = save_in_omp_for;
  return ret;
}

/* Parse a conditional expression (C90 6.3.15, C99 6.5.15, C11 6.5.15).  If
   AFTER is not NULL then it is an Objective-C message expression which is
   the primary-expression starting the expression as an initializer.

   conditional-expression:
     logical-OR-expression
     logical-OR-expression ? expression : conditional-expression

   GNU extensions:

   conditional-expression:
     logical-OR-expression ? : conditional-expression
*/

static struct c_expr
c_parser_conditional_expression (c_parser *parser, struct c_expr *after,
                                 tree omp_atomic_lhs)
{
  struct c_expr cond, exp1, exp2, ret;
  location_t start, cond_loc, colon_loc;
  bool save_c_omp_array_section_p = c_omp_array_section_p;

  gcc_assert (!after || c_dialect_objc ());

  cond = c_parser_binary_expression (parser, after, omp_atomic_lhs);

  if (c_parser_next_token_is_not (parser, CPP_QUERY))
    return cond;
  c_omp_array_section_p = false;
  if (cond.value != error_mark_node)
    start = cond.get_start ();
  else
    start = UNKNOWN_LOCATION;
  cond_loc = c_parser_peek_token (parser)->location;
  cond = convert_lvalue_to_rvalue (cond_loc, cond, true, true);
  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_COLON))
    {
      tree eptype = NULL_TREE;

      location_t middle_loc = c_parser_peek_token (parser)->location;
      pedwarn (middle_loc, OPT_Wpedantic,
               "ISO C forbids omitting the middle term of a %<?:%> expression");
      if (TREE_CODE (cond.value) == EXCESS_PRECISION_EXPR)
        {
          eptype = TREE_TYPE (cond.value);
          cond.value = TREE_OPERAND (cond.value, 0);
        }
      tree e = cond.value;
      while (TREE_CODE (e) == COMPOUND_EXPR)
        e = TREE_OPERAND (e, 1);
      warn_for_omitted_condop (middle_loc, e);
      /* Make sure first operand is calculated only once.  */
      exp1.value = save_expr (default_conversion (cond.value));
      if (eptype)
        exp1.value = build1 (EXCESS_PRECISION_EXPR, eptype, exp1.value);
      exp1.original_type = NULL;
      exp1.src_range = cond.src_range;
      cond.value = c_objc_common_truthvalue_conversion (cond_loc, exp1.value);
      c_inhibit_evaluation_warnings += cond.value == truthvalue_true_node;
    }
  else
    {
      cond.value
        = c_objc_common_truthvalue_conversion
        (cond_loc, default_conversion (cond.value));
      c_inhibit_evaluation_warnings += cond.value == truthvalue_false_node;
      exp1 = c_parser_expression_conv (parser);
      mark_exp_read (exp1.value);
      c_inhibit_evaluation_warnings +=
        ((cond.value == truthvalue_true_node)
         - (cond.value == truthvalue_false_node));
    }

  colon_loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
    {
      c_inhibit_evaluation_warnings -= cond.value == truthvalue_true_node;
      ret.set_error ();
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
      c_omp_array_section_p = save_c_omp_array_section_p;
      return ret;
    }
  {
    location_t exp2_loc = c_parser_peek_token (parser)->location;
    exp2 = c_parser_conditional_expression (parser, NULL, NULL_TREE);
    exp2 = convert_lvalue_to_rvalue (exp2_loc, exp2, true, true);
  }
  c_inhibit_evaluation_warnings -= cond.value == truthvalue_true_node;
  location_t loc1 = make_location (exp1.get_start (), exp1.src_range);
  location_t loc2 = make_location (exp2.get_start (), exp2.src_range);
  if (UNLIKELY (omp_atomic_lhs != NULL)
      && (TREE_CODE (cond.value) == GT_EXPR
          || TREE_CODE (cond.value) == LT_EXPR
          || TREE_CODE (cond.value) == EQ_EXPR)
      && c_tree_equal (exp2.value, omp_atomic_lhs)
      && (c_tree_equal (TREE_OPERAND (cond.value, 0), omp_atomic_lhs)
          || c_tree_equal (TREE_OPERAND (cond.value, 1), omp_atomic_lhs)))
    ret.value = build3_loc (colon_loc, COND_EXPR, TREE_TYPE (omp_atomic_lhs),
                            cond.value, exp1.value, exp2.value);
  else
    ret.value
      = build_conditional_expr (colon_loc, cond.value,
                                cond.original_code == C_MAYBE_CONST_EXPR,
                                exp1.value, exp1.original_type, loc1,
                                exp2.value, exp2.original_type, loc2);
  ret.original_code = ERROR_MARK;
  if (exp1.value == error_mark_node || exp2.value == error_mark_node)
    ret.original_type = NULL;
  else
    {
      tree t1, t2;

      /* If both sides are enum type, the default conversion will have
         made the type of the result be an integer type.  We want to
         remember the enum types we started with.  */
      t1 = exp1.original_type ? exp1.original_type : TREE_TYPE (exp1.value);
      t2 = exp2.original_type ? exp2.original_type : TREE_TYPE (exp2.value);
      ret.original_type = ((t1 != error_mark_node
                            && t2 != error_mark_node
                            && (TYPE_MAIN_VARIANT (t1)
                                == TYPE_MAIN_VARIANT (t2)))
                           ? t1
                           : NULL);
    }
  set_c_expr_source_range (&ret, start, exp2.get_finish ());
  ret.m_decimal = 0;
  c_omp_array_section_p = save_c_omp_array_section_p;
  return ret;
}

/* Parse a binary expression; that is, a logical-OR-expression (C90
   6.3.5-6.3.14, C99 6.5.5-6.5.14, C11 6.5.5-6.5.14).  If AFTER is not
   NULL then it is an Objective-C message expression which is the
   primary-expression starting the expression as an initializer.

   OMP_ATOMIC_LHS is NULL, unless parsing OpenMP #pragma omp atomic,
   when it should be the unfolded lhs.  In a valid OpenMP source,
   one of the operands of the toplevel binary expression must be equal
   to it.  In that case, just return a build2 created binary operation
   rather than result of parser_build_binary_op.

   multiplicative-expression:
     cast-expression
     multiplicative-expression * cast-expression
     multiplicative-expression / cast-expression
     multiplicative-expression % cast-expression

   additive-expression:
     multiplicative-expression
     additive-expression + multiplicative-expression
     additive-expression - multiplicative-expression

   shift-expression:
     additive-expression
     shift-expression << additive-expression
     shift-expression >> additive-expression

   relational-expression:
     shift-expression
     relational-expression < shift-expression
     relational-expression > shift-expression
     relational-expression <= shift-expression
     relational-expression >= shift-expression

   equality-expression:
     relational-expression
     equality-expression == relational-expression
     equality-expression != relational-expression

   AND-expression:
     equality-expression
     AND-expression & equality-expression

   exclusive-OR-expression:
     AND-expression
     exclusive-OR-expression ^ AND-expression

   inclusive-OR-expression:
     exclusive-OR-expression
     inclusive-OR-expression | exclusive-OR-expression

   logical-AND-expression:
     inclusive-OR-expression
     logical-AND-expression && inclusive-OR-expression

   logical-OR-expression:
     logical-AND-expression
     logical-OR-expression || logical-AND-expression
*/

static struct c_expr
c_parser_binary_expression (c_parser *parser, struct c_expr *after,
                            tree omp_atomic_lhs)
{
  /* A binary expression is parsed using operator-precedence parsing,
     with the operands being cast expressions.  All the binary
     operators are left-associative.  Thus a binary expression is of
     form:

     E0 op1 E1 op2 E2 ...

     which we represent on a stack.  On the stack, the precedence
     levels are strictly increasing.  When a new operator is
     encountered of higher precedence than that at the top of the
     stack, it is pushed; its LHS is the top expression, and its RHS
     is everything parsed until it is popped.  When a new operator is
     encountered with precedence less than or equal to that at the top
     of the stack, triples E[i-1] op[i] E[i] are popped and replaced
     by the result of the operation until the operator at the top of
     the stack has lower precedence than the new operator or there is
     only one element on the stack; then the top expression is the LHS
     of the new operator.  In the case of logical AND and OR
     expressions, we also need to adjust c_inhibit_evaluation_warnings
     as appropriate when the operators are pushed and popped.  */

  struct {
    /* The expression at this stack level.  */
    struct c_expr expr;
    /* The precedence of the operator on its left, PREC_NONE at the
       bottom of the stack.  */
    enum c_parser_prec prec;
    /* The operation on its left.  */
    enum tree_code op;
    /* The source location of this operation.  */
    location_t loc;
    /* The sizeof argument if expr.original_code == {PAREN_,}SIZEOF_EXPR.  */
    tree sizeof_arg;
  } stack[NUM_PRECS];
  int sp;
  /* Location of the binary operator.  */
  location_t binary_loc = UNKNOWN_LOCATION;  /* Quiet warning.  */
#define POP                                                                   \
  do {                                                                        \
    switch (stack[sp].op)                                                     \
      {                                                                       \
      case TRUTH_ANDIF_EXPR:                                                  \
        c_inhibit_evaluation_warnings -= (stack[sp - 1].expr.value            \
                                          == truthvalue_false_node);          \
        break;                                                                \
      case TRUTH_ORIF_EXPR:                                                   \
        c_inhibit_evaluation_warnings -= (stack[sp - 1].expr.value            \
                                          == truthvalue_true_node);           \
        break;                                                                \
      case TRUNC_DIV_EXPR:                                                    \
        if ((stack[sp - 1].expr.original_code == SIZEOF_EXPR                  \
             || stack[sp - 1].expr.original_code == PAREN_SIZEOF_EXPR)        \
            && (stack[sp].expr.original_code == SIZEOF_EXPR                   \
                || stack[sp].expr.original_code == PAREN_SIZEOF_EXPR))        \
          {                                                                   \
            tree type0 = stack[sp - 1].sizeof_arg;                            \
            tree type1 = stack[sp].sizeof_arg;                                \
            tree first_arg = type0;                                           \
            if (!TYPE_P (type0))                                              \
              type0 = TREE_TYPE (type0);                                      \
            if (!TYPE_P (type1))                                              \
              type1 = TREE_TYPE (type1);                                      \
            if (POINTER_TYPE_P (type0)                                        \
                && comptypes (TREE_TYPE (type0), type1)                       \
                && !(TREE_CODE (first_arg) == PARM_DECL                       \
                     && C_ARRAY_PARAMETER (first_arg)                         \
                     && warn_sizeof_array_argument))                          \
              {                                                               \
                auto_diagnostic_group d;                                      \
                if (warning_at (stack[sp].loc, OPT_Wsizeof_pointer_div,       \
                                  "division %<sizeof (%T) / sizeof (%T)%> "   \
                                  "does not compute the number of array "     \
                                  "elements",                                 \
                                  type0, type1))                              \
                  if (DECL_P (first_arg))                                     \
                    inform (DECL_SOURCE_LOCATION (first_arg),                 \
                              "first %<sizeof%> operand was declared here");  \
              }                                                               \
            else if (TREE_CODE (type0) == ARRAY_TYPE                          \
                     && !char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type0)))  \
                     && stack[sp].expr.original_code != PAREN_SIZEOF_EXPR)    \
              maybe_warn_sizeof_array_div (stack[sp].loc, first_arg, type0,   \
                                           stack[sp].sizeof_arg, type1);      \
          }                                                                   \
        break;                                                                \
      default:                                                                \
        break;                                                                \
      }                                                                       \
    stack[sp - 1].expr                                                        \
      = convert_lvalue_to_rvalue (stack[sp - 1].loc,                          \
                                  stack[sp - 1].expr, true, true);            \
    stack[sp].expr                                                            \
      = convert_lvalue_to_rvalue (stack[sp].loc,                              \
                                  stack[sp].expr, true, true);                \
    if (UNLIKELY (omp_atomic_lhs != NULL_TREE) && sp == 1                     \
        && ((c_parser_next_token_is (parser, CPP_SEMICOLON)                   \
             && ((1 << stack[sp].prec)                                        \
                 & ((1 << PREC_BITOR) | (1 << PREC_BITXOR)                    \
                     | (1 << PREC_BITAND) | (1 << PREC_SHIFT)                 \
                     | (1 << PREC_ADD) | (1 << PREC_MULT)                     \
                     | (1 << PREC_EQ))))                                      \
            || ((c_parser_next_token_is (parser, CPP_QUERY)                   \
                 || (omp_atomic_lhs == void_list_node                         \
                     && c_parser_next_token_is (parser, CPP_CLOSE_PAREN)))    \
                && (stack[sp].prec == PREC_REL || stack[sp].prec == PREC_EQ)))\
        && stack[sp].op != TRUNC_MOD_EXPR                                     \
        && stack[sp].op != GE_EXPR                                            \
        && stack[sp].op != LE_EXPR                                            \
        && stack[sp].op != NE_EXPR                                            \
        && stack[0].expr.value != error_mark_node                             \
        && stack[1].expr.value != error_mark_node                             \
        && (omp_atomic_lhs == void_list_node                                  \
            || c_tree_equal (stack[0].expr.value, omp_atomic_lhs)             \
            || c_tree_equal (stack[1].expr.value, omp_atomic_lhs)             \
            || (stack[sp].op == EQ_EXPR                                       \
                && c_parser_peek_2nd_token (parser)->keyword == RID_IF)))     \
      {                                                                       \
        tree t = make_node (stack[1].op);                                     \
        TREE_TYPE (t) = TREE_TYPE (stack[0].expr.value);                      \
        TREE_OPERAND (t, 0) = stack[0].expr.value;                            \
        TREE_OPERAND (t, 1) = stack[1].expr.value;                            \
        stack[0].expr.value = t;                                              \
        stack[0].expr.m_decimal = 0;                                          \
      }                                                                       \
    else                                                                      \
      stack[sp - 1].expr = parser_build_binary_op (stack[sp].loc,             \
                                                   stack[sp].op,              \
                                                   stack[sp - 1].expr,        \
                                                   stack[sp].expr);           \
    sp--;                                                                     \
  } while (0)
  gcc_assert (!after || c_dialect_objc ());
  stack[0].loc = c_parser_peek_token (parser)->location;
  stack[0].expr = c_parser_cast_expression (parser, after);
  stack[0].prec = PREC_NONE;
  stack[0].sizeof_arg = c_last_sizeof_arg;
  sp = 0;
  while (true)
    {
      enum c_parser_prec oprec;
      enum tree_code ocode;
      source_range src_range;
      if (parser->error)
        goto out;
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_MULT:
          oprec = PREC_MULT;
          ocode = MULT_EXPR;
          break;
        case CPP_DIV:
          oprec = PREC_MULT;
          ocode = TRUNC_DIV_EXPR;
          break;
        case CPP_MOD:
          oprec = PREC_MULT;
          ocode = TRUNC_MOD_EXPR;
          break;
        case CPP_PLUS:
          oprec = PREC_ADD;
          ocode = PLUS_EXPR;
          break;
        case CPP_MINUS:
          oprec = PREC_ADD;
          ocode = MINUS_EXPR;
          break;
        case CPP_LSHIFT:
          oprec = PREC_SHIFT;
          ocode = LSHIFT_EXPR;
          break;
        case CPP_RSHIFT:
          oprec = PREC_SHIFT;
          ocode = RSHIFT_EXPR;
          break;
        case CPP_LESS:
          oprec = PREC_REL;
          ocode = LT_EXPR;
          break;
        case CPP_GREATER:
          oprec = PREC_REL;
          ocode = GT_EXPR;
          break;
        case CPP_LESS_EQ:
          oprec = PREC_REL;
          ocode = LE_EXPR;
          break;
        case CPP_GREATER_EQ:
          oprec = PREC_REL;
          ocode = GE_EXPR;
          break;
        case CPP_EQ_EQ:
          oprec = PREC_EQ;
          ocode = EQ_EXPR;
          break;
        case CPP_NOT_EQ:
          oprec = PREC_EQ;
          ocode = NE_EXPR;
          break;
        case CPP_AND:
          oprec = PREC_BITAND;
          ocode = BIT_AND_EXPR;
          break;
        case CPP_XOR:
          oprec = PREC_BITXOR;
          ocode = BIT_XOR_EXPR;
          break;
        case CPP_OR:
          oprec = PREC_BITOR;
          ocode = BIT_IOR_EXPR;
          break;
        case CPP_AND_AND:
          oprec = PREC_LOGAND;
          ocode = TRUTH_ANDIF_EXPR;
          break;
        case CPP_OR_OR:
          oprec = PREC_LOGOR;
          ocode = TRUTH_ORIF_EXPR;
          break;
        default:
          /* Not a binary operator, so end of the binary
             expression.  */
          goto out;
        }
      binary_loc = c_parser_peek_token (parser)->location;
      while (oprec <= stack[sp].prec)
        POP;
      c_parser_consume_token (parser);
      switch (ocode)
        {
        case TRUTH_ANDIF_EXPR:
          src_range = stack[sp].expr.src_range;
          stack[sp].expr
            = convert_lvalue_to_rvalue (stack[sp].loc,
                                        stack[sp].expr, true, true);
          stack[sp].expr.value = c_objc_common_truthvalue_conversion
            (stack[sp].loc, default_conversion (stack[sp].expr.value));
          c_inhibit_evaluation_warnings += (stack[sp].expr.value
                                            == truthvalue_false_node);
          set_c_expr_source_range (&stack[sp].expr, src_range);
          break;
        case TRUTH_ORIF_EXPR:
          src_range = stack[sp].expr.src_range;
          stack[sp].expr
            = convert_lvalue_to_rvalue (stack[sp].loc,
                                        stack[sp].expr, true, true);
          stack[sp].expr.value = c_objc_common_truthvalue_conversion
            (stack[sp].loc, default_conversion (stack[sp].expr.value));
          c_inhibit_evaluation_warnings += (stack[sp].expr.value
                                            == truthvalue_true_node);
          set_c_expr_source_range (&stack[sp].expr, src_range);
          break;
        default:
          break;
        }
      sp++;
      stack[sp].loc = binary_loc;
      stack[sp].expr = c_parser_cast_expression (parser, NULL);
      stack[sp].prec = oprec;
      stack[sp].op = ocode;
      stack[sp].sizeof_arg = c_last_sizeof_arg;
    }
 out:
  while (sp > 0)
    POP;
  return stack[0].expr;
#undef POP
}

/* Parse any storage class specifiers after an open parenthesis in a
   context where a compound literal is permitted.  */

static struct c_declspecs *
c_parser_compound_literal_scspecs (c_parser *parser)
{
  bool seen_scspec = false;
  struct c_declspecs *specs = build_null_declspecs ();
  while (c_parser_next_token_is (parser, CPP_KEYWORD))
    {
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_CONSTEXPR:
        case RID_REGISTER:
        case RID_STATIC:
        case RID_THREAD:
          seen_scspec = true;
          declspecs_add_scspec (c_parser_peek_token (parser)->location,
                                specs, c_parser_peek_token (parser)->value);
          c_parser_consume_token (parser);
          break;
        default:
          goto out;
        }
    }
 out:
  return seen_scspec ? specs : NULL;
}

/* Parse a cast expression (C90 6.3.4, C99 6.5.4, C11 6.5.4).  If AFTER
   is not NULL then it is an Objective-C message expression which is the
   primary-expression starting the expression as an initializer.

   cast-expression:
     unary-expression
     ( type-name ) unary-expression
*/

static struct c_expr
c_parser_cast_expression (c_parser *parser, struct c_expr *after)
{
  location_t cast_loc = c_parser_peek_token (parser)->location;
  gcc_assert (!after || c_dialect_objc ());
  if (after)
    return c_parser_postfix_expression_after_primary (parser,
                                                      cast_loc, *after);
  /* If the expression begins with a parenthesized type name, it may
     be either a cast or a compound literal; we need to see whether
     the next character is '{' to tell the difference.  If not, it is
     an unary expression.  Full detection of unknown typenames here
     would require a 3-token lookahead.  */
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)
      && c_token_starts_compound_literal (c_parser_peek_2nd_token (parser)))
    {
      struct c_declspecs *scspecs;
      struct c_type_name *type_name;
      struct c_expr ret;
      struct c_expr expr;
      matching_parens parens;
      parens.consume_open (parser);
      scspecs = c_parser_compound_literal_scspecs (parser);
      type_name = c_parser_type_name (parser, true);
      parens.skip_until_found_close (parser);
      if (type_name == NULL)
        {
          ret.set_error ();
          ret.original_code = ERROR_MARK;
          ret.original_type = NULL;
          return ret;
        }

      /* Save casted types in the function's used types hash table.  */
      used_types_insert (type_name->specs->type);

      if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
        return c_parser_postfix_expression_after_paren_type (parser, scspecs,
                                                             type_name,
                                                             cast_loc);
      if (scspecs)
        error_at (cast_loc, "storage class specifier in cast");
      if (type_name->specs->alignas_p)
        error_at (type_name->specs->locations[cdw_alignas],
                  "alignment specified for type name in cast");
      {
        location_t expr_loc = c_parser_peek_token (parser)->location;
        expr = c_parser_cast_expression (parser, NULL);
        expr = convert_lvalue_to_rvalue (expr_loc, expr, true, true);
      }
      ret.value = c_cast_expr (cast_loc, type_name, expr.value);
      if (ret.value && expr.value)
        set_c_expr_source_range (&ret, cast_loc, expr.get_finish ());
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
      ret.m_decimal = 0;
      return ret;
    }
  else
    return c_parser_unary_expression (parser);
}

/* Parse an unary expression (C90 6.3.3, C99 6.5.3, C11 6.5.3).

   unary-expression:
     postfix-expression
     ++ unary-expression
     -- unary-expression
     unary-operator cast-expression
     sizeof unary-expression
     sizeof ( type-name )

   unary-operator: one of
     & * + - ~ !

   GNU extensions:

   unary-expression:
     __alignof__ unary-expression
     __alignof__ ( type-name )
     && identifier

   (C11 permits _Alignof with type names only.)

   unary-operator: one of
     __extension__ __real__ __imag__

   Transactional Memory:

   unary-expression:
     transaction-expression

   In addition, the GNU syntax treats ++ and -- as unary operators, so
   they may be applied to cast expressions with errors for non-lvalues
   given later.  */

static struct c_expr
c_parser_unary_expression (c_parser *parser)
{
  int ext;
  struct c_expr ret, op;
  location_t op_loc = c_parser_peek_token (parser)->location;
  location_t exp_loc;
  location_t finish;
  ret.original_code = ERROR_MARK;
  ret.original_type = NULL;
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_PLUS_PLUS:
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);

      op = default_function_array_read_conversion (exp_loc, op);
      return parser_build_unary_op (op_loc, PREINCREMENT_EXPR, op);
    case CPP_MINUS_MINUS:
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);
      
      op = default_function_array_read_conversion (exp_loc, op);
      return parser_build_unary_op (op_loc, PREDECREMENT_EXPR, op);
    case CPP_AND:
      c_parser_consume_token (parser);
      op = c_parser_cast_expression (parser, NULL);
      mark_exp_read (op.value);
      return parser_build_unary_op (op_loc, ADDR_EXPR, op);
    case CPP_MULT:
      {
        c_parser_consume_token (parser);
        exp_loc = c_parser_peek_token (parser)->location;
        op = c_parser_cast_expression (parser, NULL);
        finish = op.get_finish ();
        op = convert_lvalue_to_rvalue (exp_loc, op, true, true);
        location_t combined_loc = make_location (op_loc, op_loc, finish);
        ret.value = build_indirect_ref (combined_loc, op.value, RO_UNARY_STAR);
        ret.src_range.m_start = op_loc;
        ret.src_range.m_finish = finish;
        ret.m_decimal = 0;
        return ret;
      }
    case CPP_PLUS:
      if (!c_dialect_objc () && !in_system_header_at (input_location))
        warning_at (op_loc,
                    OPT_Wtraditional,
                    "traditional C rejects the unary plus operator");
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);
      op = convert_lvalue_to_rvalue (exp_loc, op, true, true);
      return parser_build_unary_op (op_loc, CONVERT_EXPR, op);
    case CPP_MINUS:
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);
      op = convert_lvalue_to_rvalue (exp_loc, op, true, true);
      return parser_build_unary_op (op_loc, NEGATE_EXPR, op);
    case CPP_COMPL:
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);
      op = convert_lvalue_to_rvalue (exp_loc, op, true, true);
      return parser_build_unary_op (op_loc, BIT_NOT_EXPR, op);
    case CPP_NOT:
      c_parser_consume_token (parser);
      exp_loc = c_parser_peek_token (parser)->location;
      op = c_parser_cast_expression (parser, NULL);
      op = convert_lvalue_to_rvalue (exp_loc, op, true, true);
      return parser_build_unary_op (op_loc, TRUTH_NOT_EXPR, op);
    case CPP_AND_AND:
      /* Refer to the address of a label as a pointer.  */
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          ret.value = finish_label_address_expr
            (c_parser_peek_token (parser)->value, op_loc);
          set_c_expr_source_range (&ret, op_loc,
                                   c_parser_peek_token (parser)->get_finish ());
          c_parser_consume_token (parser);
        }
      else
        {
          c_parser_error (parser, "expected identifier");
          ret.set_error ();
        }
      return ret;
    case CPP_KEYWORD:
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_SIZEOF:
          return c_parser_sizeof_expression (parser);
        case RID_ALIGNOF:
          return c_parser_alignof_expression (parser);
        case RID_BUILTIN_HAS_ATTRIBUTE:
          return c_parser_has_attribute_expression (parser);
        case RID_EXTENSION:
          c_parser_consume_token (parser);
          ext = disable_extension_diagnostics ();
          ret = c_parser_cast_expression (parser, NULL);
          restore_extension_diagnostics (ext);
          return ret;
        case RID_REALPART:
          c_parser_consume_token (parser);
          exp_loc = c_parser_peek_token (parser)->location;
          op = c_parser_cast_expression (parser, NULL);
          op = default_function_array_conversion (exp_loc, op);
          return parser_build_unary_op (op_loc, REALPART_EXPR, op);
        case RID_IMAGPART:
          c_parser_consume_token (parser);
          exp_loc = c_parser_peek_token (parser)->location;
          op = c_parser_cast_expression (parser, NULL);
          op = default_function_array_conversion (exp_loc, op);
          return parser_build_unary_op (op_loc, IMAGPART_EXPR, op);
        case RID_TRANSACTION_ATOMIC:
        case RID_TRANSACTION_RELAXED:
          return c_parser_transaction_expression (parser,
              c_parser_peek_token (parser)->keyword);
        default:
          return c_parser_postfix_expression (parser);
        }
    default:
      return c_parser_postfix_expression (parser);
    }
}

/* Parse a sizeof expression.  */

static struct c_expr
c_parser_sizeof_expression (c_parser *parser)
{
  struct c_expr expr;
  struct c_expr result;
  location_t expr_loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_SIZEOF));

  location_t start;
  location_t finish = UNKNOWN_LOCATION;

  start = c_parser_peek_token (parser)->location;

  c_parser_consume_token (parser);
  c_inhibit_evaluation_warnings++;
  in_sizeof++;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)
      && c_token_starts_compound_literal (c_parser_peek_2nd_token (parser)))
    {
      /* Either sizeof ( type-name ) or sizeof unary-expression
         starting with a compound literal.  */
      struct c_declspecs *scspecs;
      struct c_type_name *type_name;
      matching_parens parens;
      parens.consume_open (parser);
      expr_loc = c_parser_peek_token (parser)->location;
      scspecs = c_parser_compound_literal_scspecs (parser);
      type_name = c_parser_type_name (parser, true);
      parens.skip_until_found_close (parser);
      finish = parser->tokens_buf[0].location;
      if (type_name == NULL)
        {
          struct c_expr ret;
          c_inhibit_evaluation_warnings--;
          in_sizeof--;
          ret.set_error ();
          ret.original_code = ERROR_MARK;
          ret.original_type = NULL;
          return ret;
        }
      if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
        {
          expr = c_parser_postfix_expression_after_paren_type (parser, scspecs,
                                                               type_name,
                                                               expr_loc);
          finish = expr.get_finish ();
          goto sizeof_expr;
        }
      /* sizeof ( type-name ).  */
      if (scspecs)
        error_at (expr_loc, "storage class specifier in %<sizeof%>");
      if (type_name->specs->alignas_p)
        error_at (type_name->specs->locations[cdw_alignas],
                  "alignment specified for type name in %<sizeof%>");
      c_inhibit_evaluation_warnings--;
      in_sizeof--;
      result = c_expr_sizeof_type (expr_loc, type_name);
    }
  else
    {
      expr_loc = c_parser_peek_token (parser)->location;
      expr = c_parser_unary_expression (parser);
      finish = expr.get_finish ();
    sizeof_expr:
      c_inhibit_evaluation_warnings--;
      in_sizeof--;
      mark_exp_read (expr.value);
      if (TREE_CODE (expr.value) == COMPONENT_REF
          && DECL_C_BIT_FIELD (TREE_OPERAND (expr.value, 1)))
        error_at (expr_loc, "%<sizeof%> applied to a bit-field");
      result = c_expr_sizeof_expr (expr_loc, expr);
    }
  if (finish == UNKNOWN_LOCATION)
    finish = start;
  set_c_expr_source_range (&result, start, finish);
  return result;
}

/* Parse an alignof expression.  */

static struct c_expr
c_parser_alignof_expression (c_parser *parser)
{
  struct c_expr expr;
  location_t start_loc = c_parser_peek_token (parser)->location;
  location_t end_loc;
  tree alignof_spelling = c_parser_peek_token (parser)->value;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_ALIGNOF));
  bool is_c11_alignof = (strcmp (IDENTIFIER_POINTER (alignof_spelling),
                                "_Alignof") == 0
                         || strcmp (IDENTIFIER_POINTER (alignof_spelling),
                                    "alignof") == 0);
  /* A diagnostic is not required for the use of this identifier in
     the implementation namespace; only diagnose it for the C11 or C23
     spelling because of existing code using the other spellings.  */
  if (is_c11_alignof)
    {
      if (flag_isoc99)
        pedwarn_c99 (start_loc, OPT_Wpedantic, "ISO C99 does not support %qE",
                     alignof_spelling);
      else
        pedwarn_c99 (start_loc, OPT_Wpedantic, "ISO C90 does not support %qE",
                     alignof_spelling);
    }
  c_parser_consume_token (parser);
  c_inhibit_evaluation_warnings++;
  in_alignof++;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)
      && c_token_starts_compound_literal (c_parser_peek_2nd_token (parser)))
    {
      /* Either __alignof__ ( type-name ) or __alignof__
         unary-expression starting with a compound literal.  */
      location_t loc;
      struct c_declspecs *scspecs;
      struct c_type_name *type_name;
      struct c_expr ret;
      matching_parens parens;
      parens.consume_open (parser);
      loc = c_parser_peek_token (parser)->location;
      scspecs = c_parser_compound_literal_scspecs (parser);
      type_name = c_parser_type_name (parser, true);
      end_loc = c_parser_peek_token (parser)->location;
      parens.skip_until_found_close (parser);
      if (type_name == NULL)
        {
          struct c_expr ret;
          c_inhibit_evaluation_warnings--;
          in_alignof--;
          ret.set_error ();
          ret.original_code = ERROR_MARK;
          ret.original_type = NULL;
          return ret;
        }
      if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
        {
          expr = c_parser_postfix_expression_after_paren_type (parser, scspecs,
                                                               type_name,
                                                               loc);
          goto alignof_expr;
        }
      /* alignof ( type-name ).  */
      if (scspecs)
        error_at (loc, "storage class specifier in %qE", alignof_spelling);
      if (type_name->specs->alignas_p)
        error_at (type_name->specs->locations[cdw_alignas],
                  "alignment specified for type name in %qE",
                  alignof_spelling);
      c_inhibit_evaluation_warnings--;
      in_alignof--;
      ret.value = c_sizeof_or_alignof_type (loc, groktypename (type_name,
                                                               NULL, NULL),
                                            false, is_c11_alignof, 1);
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
      set_c_expr_source_range (&ret, start_loc, end_loc);
      ret.m_decimal = 0;
      return ret;
    }
  else
    {
      struct c_expr ret;
      expr = c_parser_unary_expression (parser);
      end_loc = expr.src_range.m_finish;
    alignof_expr:
      mark_exp_read (expr.value);
      c_inhibit_evaluation_warnings--;
      in_alignof--;
      if (is_c11_alignof)
        pedwarn (start_loc,
                 OPT_Wpedantic, "ISO C does not allow %<%E (expression)%>",
                 alignof_spelling);
      ret.value = c_alignof_expr (start_loc, expr.value);
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
      set_c_expr_source_range (&ret, start_loc, end_loc);
      ret.m_decimal = 0;
      return ret;
    }
}

/* Parse the __builtin_has_attribute ([expr|type], attribute-spec)
   expression.  */

static struct c_expr
c_parser_has_attribute_expression (c_parser *parser)
{
  gcc_assert (c_parser_next_token_is_keyword (parser,
                                              RID_BUILTIN_HAS_ATTRIBUTE));
  location_t start = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);

  c_inhibit_evaluation_warnings++;

  matching_parens parens;
  if (!parens.require_open (parser))
    {
      c_inhibit_evaluation_warnings--;
      in_typeof--;

      struct c_expr result;
      result.set_error ();
      result.original_code = ERROR_MARK;
      result.original_type = NULL;
      return result;
    }

  /* Treat the type argument the same way as in typeof for the purposes
     of warnings.  FIXME: Generalize this so the warning refers to
     __builtin_has_attribute rather than typeof.  */
  in_typeof++;

  /* The first operand: one of DECL, EXPR, or TYPE.  */
  tree oper = NULL_TREE;
  if (c_parser_next_tokens_start_typename (parser, cla_prefer_id))
    {
      struct c_type_name *tname = c_parser_type_name (parser);
      in_typeof--;
      if (tname)
        {
          oper = groktypename (tname, NULL, NULL);
          pop_maybe_used (c_type_variably_modified_p (oper));
        }
    }
  else
    {
      struct c_expr cexpr = c_parser_expr_no_commas (parser, NULL);
      c_inhibit_evaluation_warnings--;
      in_typeof--;
      if (cexpr.value != error_mark_node)
        {
          mark_exp_read (cexpr.value);
          oper = cexpr.value;
          tree etype = TREE_TYPE (oper);
          bool was_vm = c_type_variably_modified_p (etype);
          /* This is returned with the type so that when the type is
             evaluated, this can be evaluated.  */
          if (was_vm)
            oper = c_fully_fold (oper, false, NULL);
          pop_maybe_used (was_vm);
        }
    }

  struct c_expr result;
  result.original_code = ERROR_MARK;
  result.original_type = NULL;

  if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
    {
      /* Consume the closing parenthesis if that's the next token
         in the likely case the built-in was invoked with fewer
         than two arguments.  */
      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        c_parser_consume_token (parser);
      c_inhibit_evaluation_warnings--;
      result.set_error ();
      return result;
    }

  bool save_translate_strings_p = parser->translate_strings_p;

  location_t atloc = c_parser_peek_token (parser)->location;
  /* Parse a single attribute.  Require no leading comma and do not
     allow empty attributes.  */
  tree attr = c_parser_gnu_attribute (parser, NULL_TREE, false, false);

  parser->translate_strings_p = save_translate_strings_p;

  location_t finish = c_parser_peek_token (parser)->location;
  if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
    c_parser_consume_token (parser);
  else
    {
      c_parser_error (parser, "expected identifier");
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);

      result.set_error ();
      return result;
    }

  if (!attr)
    {
      error_at (atloc, "expected identifier");
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                 "expected %<)%>");
      result.set_error ();
      return result;
    }

  result.original_code = INTEGER_CST;
  result.original_type = boolean_type_node;

  if (has_attribute (atloc, oper, attr, default_conversion))
    result.value = boolean_true_node;
  else
    result.value =  boolean_false_node;

  set_c_expr_source_range (&result, start, finish);
  result.m_decimal = 0;
  return result;
}

/* Helper function to read arguments of builtins which are interfaces
   for the middle-end nodes like COMPLEX_EXPR, VEC_PERM_EXPR and
   others.  The name of the builtin is passed using BNAME parameter.
   Function returns true if there were no errors while parsing and
   stores the arguments in CEXPR_LIST.  If it returns true,
   *OUT_CLOSE_PAREN_LOC is written to with the location of the closing
   parenthesis.  */
static bool
c_parser_get_builtin_args (c_parser *parser, const char *bname,
                           vec<c_expr_t, va_gc> **ret_cexpr_list,
                           bool choose_expr_p,
                           location_t *out_close_paren_loc)
{
  location_t loc = c_parser_peek_token (parser)->location;
  vec<c_expr_t, va_gc> *cexpr_list;
  c_expr_t expr;
  bool saved_force_folding_builtin_constant_p;

  *ret_cexpr_list = NULL;
  if (c_parser_next_token_is_not (parser, CPP_OPEN_PAREN))
    {
      error_at (loc, "cannot take address of %qs", bname);
      return false;
    }

  c_parser_consume_token (parser);

  if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
    {
      *out_close_paren_loc = c_parser_peek_token (parser)->location;
      c_parser_consume_token (parser);
      return true;
    }

  saved_force_folding_builtin_constant_p
    = force_folding_builtin_constant_p;
  force_folding_builtin_constant_p |= choose_expr_p;
  expr = c_parser_expr_no_commas (parser, NULL);
  force_folding_builtin_constant_p
    = saved_force_folding_builtin_constant_p;
  vec_alloc (cexpr_list, 1);
  vec_safe_push (cexpr_list, expr);
  while (c_parser_next_token_is (parser, CPP_COMMA))
    {
      c_parser_consume_token (parser);
      expr = c_parser_expr_no_commas (parser, NULL);
      vec_safe_push (cexpr_list, expr);
    }

  *out_close_paren_loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
    return false;

  *ret_cexpr_list = cexpr_list;
  return true;
}

/* This represents a single generic-association.  */

struct c_generic_association
{
  /* The location of the starting token of the type.  */
  location_t type_location;
  /* The association's type, or NULL_TREE for 'default'.  */
  tree type;
  /* The association's expression.  */
  struct c_expr expression;
};

/* Parse a generic-selection.  (C11 6.5.1.1).
   
   generic-selection:
     _Generic ( assignment-expression , generic-assoc-list )
     
   generic-assoc-list:
     generic-association
     generic-assoc-list , generic-association
   
   generic-association:
     type-name : assignment-expression
     default : assignment-expression
*/

static struct c_expr
c_parser_generic_selection (c_parser *parser)
{
  struct c_expr selector, error_expr;
  tree selector_type;
  struct c_generic_association matched_assoc;
  int match_found = -1;
  location_t generic_loc, selector_loc;

  error_expr.original_code = ERROR_MARK;
  error_expr.original_type = NULL;
  error_expr.set_error ();
  matched_assoc.type_location = UNKNOWN_LOCATION;
  matched_assoc.type = NULL_TREE;
  matched_assoc.expression = error_expr;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_GENERIC));
  generic_loc = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);
  if (flag_isoc99)
    pedwarn_c99 (generic_loc, OPT_Wpedantic,
                 "ISO C99 does not support %<_Generic%>");
  else
    pedwarn_c99 (generic_loc, OPT_Wpedantic,
                 "ISO C90 does not support %<_Generic%>");

  matching_parens parens;
  if (!parens.require_open (parser))
    return error_expr;

  c_inhibit_evaluation_warnings++;
  selector_loc = c_parser_peek_token (parser)->location;
  selector = c_parser_expr_no_commas (parser, NULL);
  selector = default_function_array_conversion (selector_loc, selector);
  c_inhibit_evaluation_warnings--;

  if (selector.value == error_mark_node)
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
      return selector;
    }
  mark_exp_read (selector.value);
  selector_type = TREE_TYPE (selector.value);
  /* In ISO C terms, rvalues (including the controlling expression of
     _Generic) do not have qualified types.  */
  if (TREE_CODE (selector_type) != ARRAY_TYPE)
    selector_type = TYPE_MAIN_VARIANT (selector_type);
  /* In ISO C terms, _Noreturn is not part of the type of expressions
     such as &abort, but in GCC it is represented internally as a type
     qualifier.  */
  if (FUNCTION_POINTER_TYPE_P (selector_type)
      && TYPE_QUALS (TREE_TYPE (selector_type)) != TYPE_UNQUALIFIED)
    selector_type
      = build_pointer_type (TYPE_MAIN_VARIANT (TREE_TYPE (selector_type)));

  if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
      return error_expr;
    }

  auto_vec<c_generic_association> associations;
  while (1)
    {
      struct c_generic_association assoc, *iter;
      unsigned int ix;
      c_token *token = c_parser_peek_token (parser);

      assoc.type_location = token->location;
      if (token->type == CPP_KEYWORD && token->keyword == RID_DEFAULT)
        {
          c_parser_consume_token (parser);
          assoc.type = NULL_TREE;
        }
      else
        {
          struct c_type_name *type_name;

          type_name = c_parser_type_name (parser);
          if (type_name == NULL)
            {
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
              return error_expr;
            }
          assoc.type = groktypename (type_name, NULL, NULL);
          if (assoc.type == error_mark_node)
            {
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
              return error_expr;
            }

          if (TREE_CODE (assoc.type) == FUNCTION_TYPE)
            error_at (assoc.type_location,
                      "%<_Generic%> association has function type");
          else if (!COMPLETE_TYPE_P (assoc.type))
            error_at (assoc.type_location,
                      "%<_Generic%> association has incomplete type");

          if (c_type_variably_modified_p (assoc.type))
            error_at (assoc.type_location,
                      "%<_Generic%> association has "
                      "variable length type");
        }

      if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          return error_expr;
        }

      bool match = assoc.type == NULL_TREE
                   || comptypes (assoc.type, selector_type);

      if (!match)
        c_inhibit_evaluation_warnings++;

      assoc.expression = c_parser_expr_no_commas (parser, NULL);

      if (!match)
          c_inhibit_evaluation_warnings--;

      if (assoc.expression.value == error_mark_node)
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          return error_expr;
        }

      for (ix = 0; associations.iterate (ix, &iter); ++ix)
        {
          if (assoc.type == NULL_TREE)
            {
              if (iter->type == NULL_TREE)
                {
                  error_at (assoc.type_location,
                            "duplicate %<default%> case in %<_Generic%>");
                  inform (iter->type_location, "original %<default%> is here");
                }
            }
          else if (iter->type != NULL_TREE)
            {
              if (comptypes (assoc.type, iter->type))
                {
                  error_at (assoc.type_location,
                            "%<_Generic%> specifies two compatible types");
                  inform (iter->type_location, "compatible type is here");
                }
            }
        }

      if (assoc.type == NULL_TREE)
        {
          if (match_found < 0)
            {
              matched_assoc = assoc;
              match_found = associations.length ();
            }
        }
      else if (match)
        {
          if (match_found < 0 || matched_assoc.type == NULL_TREE)
            {
              matched_assoc = assoc;
              match_found = associations.length ();
            }
          else
            {
              error_at (assoc.type_location,
                        "%<_Generic%> selector matches multiple associations");
              inform (matched_assoc.type_location,
                      "other match is here");
            }
        }

      associations.safe_push (assoc);

      if (c_parser_peek_token (parser)->type != CPP_COMMA)
        break;
      c_parser_consume_token (parser);
    }

  unsigned int ix;
  struct c_generic_association *iter;
  FOR_EACH_VEC_ELT (associations, ix, iter)
    if (ix != (unsigned) match_found)
      mark_exp_read (iter->expression.value);

  if (!parens.require_close (parser))
    {
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
      return error_expr;
    }

  if (match_found < 0)
    {
      error_at (selector_loc, "%<_Generic%> selector of type %qT is not "
                "compatible with any association",
                selector_type);
      return error_expr;
    }

  return matched_assoc.expression;
}

/* Check the validity of a function pointer argument *EXPR (argument
   position POS) to __builtin_tgmath.  Return the number of function
   arguments if possibly valid; return 0 having reported an error if
   not valid.  */

static unsigned int
check_tgmath_function (c_expr *expr, unsigned int pos)
{
  tree type = TREE_TYPE (expr->value);
  if (!FUNCTION_POINTER_TYPE_P (type))
    {
      error_at (expr->get_location (),
                "argument %u of %<__builtin_tgmath%> is not a function pointer",
                pos);
      return 0;
    }
  type = TREE_TYPE (type);
  if (!prototype_p (type))
    {
      error_at (expr->get_location (),
                "argument %u of %<__builtin_tgmath%> is unprototyped", pos);
      return 0;
    }
  if (stdarg_p (type))
    {
      error_at (expr->get_location (),
                "argument %u of %<__builtin_tgmath%> has variable arguments",
                pos);
      return 0;
    }
  unsigned int nargs = 0;
  function_args_iterator iter;
  tree t;
  FOREACH_FUNCTION_ARGS (type, t, iter)
    {
      if (t == void_type_node)
        break;
      nargs++;
    }
  if (nargs == 0)
    {
      error_at (expr->get_location (),
                "argument %u of %<__builtin_tgmath%> has no arguments", pos);
      return 0;
    }
  return nargs;
}

/* Ways in which a parameter or return value of a type-generic macro
   may vary between the different functions the macro may call.  */
enum tgmath_parm_kind
  {
    tgmath_fixed, tgmath_real, tgmath_complex
  };

/* Helper function for c_parser_postfix_expression.  Parse predefined
   identifiers.  */

static struct c_expr
c_parser_predefined_identifier (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  switch (c_parser_peek_token (parser)->keyword)
    {
    case RID_FUNCTION_NAME:
      pedwarn (loc, OPT_Wpedantic, "ISO C does not support %qs predefined "
               "identifier", "__FUNCTION__");
      break;
    case RID_PRETTY_FUNCTION_NAME:
      pedwarn (loc, OPT_Wpedantic, "ISO C does not support %qs predefined "
               "identifier", "__PRETTY_FUNCTION__");
      break;
    case RID_C99_FUNCTION_NAME:
      pedwarn_c90 (loc, OPT_Wpedantic, "ISO C90 does not support "
                   "%<__func__%> predefined identifier");
      break;
    default:
      gcc_unreachable ();
    }

  struct c_expr expr;
  expr.original_code = ERROR_MARK;
  expr.original_type = NULL;
  expr.value = fname_decl (loc, c_parser_peek_token (parser)->keyword,
                           c_parser_peek_token (parser)->value);
  set_c_expr_source_range (&expr, loc, loc);
  expr.m_decimal = 0;
  c_parser_consume_token (parser);
  return expr;
}

/* Parse a postfix expression (C90 6.3.1-6.3.2, C99 6.5.1-6.5.2,
   C11 6.5.1-6.5.2).  Compound literals aren't handled here; callers have to
   call c_parser_postfix_expression_after_paren_type on encountering them.

   postfix-expression:
     primary-expression
     postfix-expression [ expression ]
     postfix-expression ( argument-expression-list[opt] )
     postfix-expression . identifier
     postfix-expression -> identifier
     postfix-expression ++
     postfix-expression --
     ( storage-class-specifiers[opt] type-name ) { initializer-list[opt] }
     ( storage-class-specifiers[opt] type-name ) { initializer-list , }

   argument-expression-list:
     argument-expression
     argument-expression-list , argument-expression

   primary-expression:
     identifier
     constant
     string-literal
     ( expression )
     generic-selection

   GNU extensions:

   primary-expression:
     __func__
       (treated as a keyword in GNU C)
     __FUNCTION__
     __PRETTY_FUNCTION__
     ( compound-statement )
     __builtin_va_arg ( assignment-expression , type-name )
     __builtin_offsetof ( type-name , offsetof-member-designator )
     __builtin_choose_expr ( assignment-expression ,
                             assignment-expression ,
                             assignment-expression )
     __builtin_types_compatible_p ( type-name , type-name )
     __builtin_tgmath ( expr-list )
     __builtin_complex ( assignment-expression , assignment-expression )
     __builtin_shuffle ( assignment-expression , assignment-expression )
     __builtin_shuffle ( assignment-expression ,
                         assignment-expression ,
                         assignment-expression, )
     __builtin_convertvector ( assignment-expression , type-name )
     __builtin_assoc_barrier ( assignment-expression )

   offsetof-member-designator:
     identifier
     offsetof-member-designator . identifier
     offsetof-member-designator [ expression ]

   Objective-C:

   primary-expression:
     [ objc-receiver objc-message-args ]
     @selector ( objc-selector-arg )
     @protocol ( identifier )
     @encode ( type-name )
     objc-string-literal
     Classname . identifier
*/

static struct c_expr
c_parser_postfix_expression (c_parser *parser)
{
  struct c_expr expr, e1;
  struct c_type_name *t1, *t2;
  location_t loc = c_parser_peek_token (parser)->location;
  source_range tok_range = c_parser_peek_token (parser)->get_range ();
  expr.original_code = ERROR_MARK;
  expr.original_type = NULL;
  expr.m_decimal = 0;
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_NUMBER:
      expr.value = c_parser_peek_token (parser)->value;
      set_c_expr_source_range (&expr, tok_range);
      loc = c_parser_peek_token (parser)->location;
      expr.m_decimal = c_parser_peek_token (parser)->flags & DECIMAL_INT;
      c_parser_consume_token (parser);
      if (TREE_CODE (expr.value) == FIXED_CST
          && !targetm.fixed_point_supported_p ())
        {
          error_at (loc, "fixed-point types not supported for this target");
          expr.set_error ();
        }
      break;
    case CPP_CHAR:
    case CPP_CHAR16:
    case CPP_CHAR32:
    case CPP_UTF8CHAR:
    case CPP_WCHAR:
      expr.value = c_parser_peek_token (parser)->value;
      /* For the purpose of warning when a pointer is compared with
         a zero character constant.  */
      expr.original_type = char_type_node;
      set_c_expr_source_range (&expr, tok_range);
      c_parser_consume_token (parser);
      break;
    case CPP_STRING:
    case CPP_STRING16:
    case CPP_STRING32:
    case CPP_WSTRING:
    case CPP_UTF8STRING:
      expr = c_parser_string_literal (parser, parser->translate_strings_p,
                                      true);
      break;
    case CPP_OBJC_STRING:
      gcc_assert (c_dialect_objc ());
      expr.value
        = objc_build_string_object (c_parser_peek_token (parser)->value);
      set_c_expr_source_range (&expr, tok_range);
      c_parser_consume_token (parser);
      break;
    case CPP_NAME:
      switch (c_parser_peek_token (parser)->id_kind)
        {
        case C_ID_ID:
          {
            tree id = c_parser_peek_token (parser)->value;
            c_parser_consume_token (parser);
            expr.value = build_external_ref (loc, id,
                                             (c_parser_peek_token (parser)->type
                                              == CPP_OPEN_PAREN),
                                             &expr.original_type);
            set_c_expr_source_range (&expr, tok_range);
            break;
          }
        case C_ID_CLASSNAME:
          {
            /* Here we parse the Objective-C 2.0 Class.name dot
               syntax.  */
            tree class_name = c_parser_peek_token (parser)->value;
            tree component;
            c_parser_consume_token (parser);
            gcc_assert (c_dialect_objc ());
            if (!c_parser_require (parser, CPP_DOT, "expected %<.%>"))
              {
                expr.set_error ();
                break;
              }
            if (c_parser_next_token_is_not (parser, CPP_NAME))
              {
                c_parser_error (parser, "expected identifier");
                expr.set_error ();
                break;
              }
            c_token *component_tok = c_parser_peek_token (parser);
            component = component_tok->value;
            location_t end_loc = component_tok->get_finish ();
            c_parser_consume_token (parser);
            expr.value = objc_build_class_component_ref (class_name, 
                                                         component);
            set_c_expr_source_range (&expr, loc, end_loc);
            break;
          }
        default:
          c_parser_error (parser, "expected expression");
          expr.set_error ();
          break;
        }
      break;
    case CPP_OPEN_PAREN:
      /* A parenthesized expression, statement expression or compound
         literal.  */
      if (c_parser_peek_2nd_token (parser)->type == CPP_OPEN_BRACE)
        {
          /* A statement expression.  */
          tree stmt;
          location_t brace_loc;
          bool save_c_omp_array_section_p = c_omp_array_section_p;
          c_parser_consume_token (parser);
          brace_loc = c_parser_peek_token (parser)->location;
          c_parser_consume_token (parser);
          /* If we've not yet started the current function's statement list,
             or we're in the parameter scope of an old-style function
             declaration, statement expressions are not allowed.  */
          if (!building_stmt_list_p () || old_style_parameter_scope ())
            {
              error_at (loc, "braced-group within expression allowed "
                        "only inside a function");
              parser->error = true;
              c_parser_skip_until_found (parser, CPP_CLOSE_BRACE, NULL);
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
              expr.set_error ();
              break;
            }
          c_omp_array_section_p = false;
          stmt = c_begin_stmt_expr ();
          c_parser_compound_statement_nostart (parser);
          location_t close_loc = c_parser_peek_token (parser)->location;
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          pedwarn (loc, OPT_Wpedantic,
                   "ISO C forbids braced-groups within expressions");
          expr.value = c_finish_stmt_expr (brace_loc, stmt);
          set_c_expr_source_range (&expr, loc, close_loc);
          mark_exp_read (expr.value);
          c_omp_array_section_p = save_c_omp_array_section_p;
        }
      else
        {
          /* A parenthesized expression.  */
          location_t loc_open_paren = c_parser_peek_token (parser)->location;
          c_parser_consume_token (parser);
          expr = c_parser_expression (parser);
          if (TREE_CODE (expr.value) == MODIFY_EXPR)
            suppress_warning (expr.value, OPT_Wparentheses);
          if (expr.original_code != C_MAYBE_CONST_EXPR
              && expr.original_code != SIZEOF_EXPR)
            expr.original_code = ERROR_MARK;
          /* Remember that we saw ( ) around the sizeof.  */
          if (expr.original_code == SIZEOF_EXPR)
            expr.original_code = PAREN_SIZEOF_EXPR;
          /* Don't change EXPR.ORIGINAL_TYPE.  */
          location_t loc_close_paren = c_parser_peek_token (parser)->location;
          set_c_expr_source_range (&expr, loc_open_paren, loc_close_paren);
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>", loc_open_paren);
        }
      break;
    case CPP_KEYWORD:
      switch (c_parser_peek_token (parser)->keyword)
        {
        case RID_FUNCTION_NAME:
        case RID_PRETTY_FUNCTION_NAME:
        case RID_C99_FUNCTION_NAME:
          expr = c_parser_predefined_identifier (parser);
          break;
        case RID_VA_ARG:
          {
            location_t start_loc = loc;
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            e1 = c_parser_expr_no_commas (parser, NULL);
            mark_exp_read (e1.value);
            e1.value = c_fully_fold (e1.value, false, NULL);
            if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
              {
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                expr.set_error ();
                break;
              }
            loc = c_parser_peek_token (parser)->location;
            t1 = c_parser_type_name (parser);
            location_t end_loc = c_parser_peek_token (parser)->get_finish ();
            c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                       "expected %<)%>");
            if (t1 == NULL)
              {
                expr.set_error ();
              }
            else
              {
                tree type_expr = NULL_TREE;
                expr.value = c_build_va_arg (start_loc, e1.value, loc,
                                             groktypename (t1, &type_expr, NULL));
                if (type_expr)
                  {
                    expr.value = build2 (C_MAYBE_CONST_EXPR,
                                         TREE_TYPE (expr.value), type_expr,
                                         expr.value);
                    C_MAYBE_CONST_EXPR_NON_CONST (expr.value) = true;
                  }
                set_c_expr_source_range (&expr, start_loc, end_loc);
              }
          }
          break;
        case RID_OFFSETOF:
          {
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            t1 = c_parser_type_name (parser);
            if (t1 == NULL)
              parser->error = true;
            if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
              gcc_assert (parser->error);
            if (parser->error)
              {
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                expr.set_error ();
                break;
              }
            tree type = groktypename (t1, NULL, NULL);
            tree offsetof_ref;
            if (type == error_mark_node)
              offsetof_ref = error_mark_node;
            else
              {
                offsetof_ref = build1 (INDIRECT_REF, type, null_pointer_node);
                SET_EXPR_LOCATION (offsetof_ref, loc);
              }
            /* Parse the second argument to __builtin_offsetof.  We
               must have one identifier, and beyond that we want to
               accept sub structure and sub array references.  */
            if (c_parser_next_token_is (parser, CPP_NAME))
              {
                c_token *comp_tok = c_parser_peek_token (parser);
                offsetof_ref
                  = build_component_ref (loc, offsetof_ref, comp_tok->value,
                                         comp_tok->location, UNKNOWN_LOCATION);
                c_parser_consume_token (parser);
                while (c_parser_next_token_is (parser, CPP_DOT)
                       || c_parser_next_token_is (parser,
                                                  CPP_OPEN_SQUARE)
                       || c_parser_next_token_is (parser,
                                                  CPP_DEREF))
                  {
                    if (c_parser_next_token_is (parser, CPP_DEREF))
                      {
                        loc = c_parser_peek_token (parser)->location;
                        offsetof_ref = build_array_ref (loc,
                                                        offsetof_ref,
                                                        integer_zero_node);
                        goto do_dot;
                      }
                    else if (c_parser_next_token_is (parser, CPP_DOT))
                      {
                      do_dot:
                        c_parser_consume_token (parser);
                        if (c_parser_next_token_is_not (parser,
                                                        CPP_NAME))
                          {
                            c_parser_error (parser, "expected identifier");
                            break;
                          }
                        c_token *comp_tok = c_parser_peek_token (parser);
                        offsetof_ref
                          = build_component_ref (loc, offsetof_ref,
                                                 comp_tok->value,
                                                 comp_tok->location,
                                                 UNKNOWN_LOCATION);
                        c_parser_consume_token (parser);
                      }
                    else
                      {
                        struct c_expr ce;
                        tree idx;
                        loc = c_parser_peek_token (parser)->location;
                        c_parser_consume_token (parser);
                        ce = c_parser_expression (parser);
                        ce = convert_lvalue_to_rvalue (loc, ce, false, false);
                        idx = ce.value;
                        idx = c_fully_fold (idx, false, NULL);
                        c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                                   "expected %<]%>");
                        offsetof_ref = build_array_ref (loc, offsetof_ref, idx);
                      }
                  }
              }
            else
              c_parser_error (parser, "expected identifier");
            location_t end_loc = c_parser_peek_token (parser)->get_finish ();
            c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                       "expected %<)%>");
            expr.value = fold_offsetof (offsetof_ref);
            set_c_expr_source_range (&expr, loc, end_loc);
          }
          break;
        case RID_CHOOSE_EXPR:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            c_expr_t *e1_p, *e2_p, *e3_p;
            tree c;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_choose_expr",
                                            &cexpr_list, true,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            if (vec_safe_length (cexpr_list) != 3)
              {
                error_at (loc, "wrong number of arguments to "
                               "%<__builtin_choose_expr%>");
                expr.set_error ();
                break;
              }

            e1_p = &(*cexpr_list)[0];
            e2_p = &(*cexpr_list)[1];
            e3_p = &(*cexpr_list)[2];

            c = e1_p->value;
            mark_exp_read (e2_p->value);
            mark_exp_read (e3_p->value);
            if (TREE_CODE (c) != INTEGER_CST
                || !INTEGRAL_TYPE_P (TREE_TYPE (c)))
              error_at (loc,
                        "first argument to %<__builtin_choose_expr%> not"
                        " a constant");
            constant_expression_warning (c);
            expr = integer_zerop (c) ? *e3_p : *e2_p;
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_TYPES_COMPATIBLE_P:
          {
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            t1 = c_parser_type_name (parser);
            if (t1 == NULL)
              {
                expr.set_error ();
                break;
              }
            if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
              {
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                expr.set_error ();
                break;
              }
            t2 = c_parser_type_name (parser);
            if (t2 == NULL)
              {
                expr.set_error ();
                break;
              }
            location_t close_paren_loc = c_parser_peek_token (parser)->location;
            parens.skip_until_found_close (parser);
            tree e1, e2;
            e1 = groktypename (t1, NULL, NULL);
            e2 = groktypename (t2, NULL, NULL);
            if (e1 == error_mark_node || e2 == error_mark_node)
              {
                expr.set_error ();
                break;
              }

            e1 = TYPE_MAIN_VARIANT (e1);
            e2 = TYPE_MAIN_VARIANT (e2);

            expr.value
              = comptypes (e1, e2) ? integer_one_node : integer_zero_node;
            set_c_expr_source_range (&expr, loc, close_paren_loc);
          }
          break;
        case RID_BUILTIN_TGMATH:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_tgmath",
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            if (vec_safe_length (cexpr_list) < 3)
              {
                error_at (loc, "too few arguments to %<__builtin_tgmath%>");
                expr.set_error ();
                break;
              }

            unsigned int i;
            c_expr_t *p;
            FOR_EACH_VEC_ELT (*cexpr_list, i, p)
              *p = convert_lvalue_to_rvalue (loc, *p, true, true);
            unsigned int nargs = check_tgmath_function (&(*cexpr_list)[0], 1);
            if (nargs == 0)
              {
                expr.set_error ();
                break;
              }
            if (vec_safe_length (cexpr_list) < nargs)
              {
                error_at (loc, "too few arguments to %<__builtin_tgmath%>");
                expr.set_error ();
                break;
              }
            unsigned int num_functions = vec_safe_length (cexpr_list) - nargs;
            if (num_functions < 2)
              {
                error_at (loc, "too few arguments to %<__builtin_tgmath%>");
                expr.set_error ();
                break;
              }

            /* The first NUM_FUNCTIONS expressions are the function
               pointers.  The remaining NARGS expressions are the
               arguments that are to be passed to one of those
               functions, chosen following <tgmath.h> rules.  */
            for (unsigned int j = 1; j < num_functions; j++)
              {
                unsigned int this_nargs
                  = check_tgmath_function (&(*cexpr_list)[j], j + 1);
                if (this_nargs == 0)
                  {
                    expr.set_error ();
                    goto out;
                  }
                if (this_nargs != nargs)
                  {
                    error_at ((*cexpr_list)[j].get_location (),
                              "argument %u of %<__builtin_tgmath%> has "
                              "wrong number of arguments", j + 1);
                    expr.set_error ();
                    goto out;
                  }
              }

            /* The functions all have the same number of arguments.
               Determine whether arguments and return types vary in
               ways permitted for <tgmath.h> functions.  */
            /* The first entry in each of these vectors is for the
               return type, subsequent entries for parameter
               types.  */
            auto_vec<enum tgmath_parm_kind> parm_kind (nargs + 1);
            auto_vec<tree> parm_first (nargs + 1);
            auto_vec<bool> parm_complex (nargs + 1);
            auto_vec<bool> parm_varies (nargs + 1);
            tree first_type = TREE_TYPE (TREE_TYPE ((*cexpr_list)[0].value));
            tree first_ret = TYPE_MAIN_VARIANT (TREE_TYPE (first_type));
            parm_first.quick_push (first_ret);
            parm_complex.quick_push (TREE_CODE (first_ret) == COMPLEX_TYPE);
            parm_varies.quick_push (false);
            function_args_iterator iter;
            tree t;
            unsigned int argpos;
            FOREACH_FUNCTION_ARGS (first_type, t, iter)
              {
                if (t == void_type_node)
                  break;
                parm_first.quick_push (TYPE_MAIN_VARIANT (t));
                parm_complex.quick_push (TREE_CODE (t) == COMPLEX_TYPE);
                parm_varies.quick_push (false);
              }
            for (unsigned int j = 1; j < num_functions; j++)
              {
                tree type = TREE_TYPE (TREE_TYPE ((*cexpr_list)[j].value));
                tree ret = TYPE_MAIN_VARIANT (TREE_TYPE (type));
                if (ret != parm_first[0])
                  {
                    parm_varies[0] = true;
                    if (!SCALAR_FLOAT_TYPE_P (parm_first[0])
                        && !COMPLEX_FLOAT_TYPE_P (parm_first[0]))
                      {
                        error_at ((*cexpr_list)[0].get_location (),
                                  "invalid type-generic return type for "
                                  "argument %u of %<__builtin_tgmath%>",
                                  1);
                        expr.set_error ();
                        goto out;
                      }
                    if (!SCALAR_FLOAT_TYPE_P (ret)
                        && !COMPLEX_FLOAT_TYPE_P (ret))
                      {
                        error_at ((*cexpr_list)[j].get_location (),
                                  "invalid type-generic return type for "
                                  "argument %u of %<__builtin_tgmath%>",
                                  j + 1);
                        expr.set_error ();
                        goto out;
                      }
                  }
                if (TREE_CODE (ret) == COMPLEX_TYPE)
                  parm_complex[0] = true;
                argpos = 1;
                FOREACH_FUNCTION_ARGS (type, t, iter)
                  {
                    if (t == void_type_node)
                      break;
                    t = TYPE_MAIN_VARIANT (t);
                    if (t != parm_first[argpos])
                      {
                        parm_varies[argpos] = true;
                        if (!SCALAR_FLOAT_TYPE_P (parm_first[argpos])
                            && !COMPLEX_FLOAT_TYPE_P (parm_first[argpos]))
                          {
                            error_at ((*cexpr_list)[0].get_location (),
                                      "invalid type-generic type for "
                                      "argument %u of argument %u of "
                                      "%<__builtin_tgmath%>", argpos, 1);
                            expr.set_error ();
                            goto out;
                          }
                        if (!SCALAR_FLOAT_TYPE_P (t)
                            && !COMPLEX_FLOAT_TYPE_P (t))
                          {
                            error_at ((*cexpr_list)[j].get_location (),
                                      "invalid type-generic type for "
                                      "argument %u of argument %u of "
                                      "%<__builtin_tgmath%>", argpos, j + 1);
                            expr.set_error ();
                            goto out;
                          }
                      }
                    if (TREE_CODE (t) == COMPLEX_TYPE)
                      parm_complex[argpos] = true;
                    argpos++;
                  }
              }
            enum tgmath_parm_kind max_variation = tgmath_fixed;
            for (unsigned int j = 0; j <= nargs; j++)
              {
                enum tgmath_parm_kind this_kind;
                if (parm_varies[j])
                  {
                    if (parm_complex[j])
                      max_variation = this_kind = tgmath_complex;
                    else
                      {
                        this_kind = tgmath_real;
                        if (max_variation != tgmath_complex)
                          max_variation = tgmath_real;
                      }
                  }
                else
                  this_kind = tgmath_fixed;
                parm_kind.quick_push (this_kind);
              }
            if (max_variation == tgmath_fixed)
              {
                error_at (loc, "function arguments of %<__builtin_tgmath%> "
                          "all have the same type");
                expr.set_error ();
                break;
              }

            /* Identify a parameter (not the return type) that varies,
               including with complex types if any variation includes
               complex types; there must be at least one such
               parameter.  */
            unsigned int tgarg = 0;
            for (unsigned int j = 1; j <= nargs; j++)
              if (parm_kind[j] == max_variation)
                {
                  tgarg = j;
                  break;
                }
            if (tgarg == 0)
              {
                error_at (loc, "function arguments of %<__builtin_tgmath%> "
                          "lack type-generic parameter");
                expr.set_error ();
                break;
              }

            /* Determine the type of the relevant parameter for each
               function.  */
            auto_vec<tree> tg_type (num_functions);
            for (unsigned int j = 0; j < num_functions; j++)
              {
                tree type = TREE_TYPE (TREE_TYPE ((*cexpr_list)[j].value));
                argpos = 1;
                FOREACH_FUNCTION_ARGS (type, t, iter)
                  {
                    if (argpos == tgarg)
                      {
                        tg_type.quick_push (TYPE_MAIN_VARIANT (t));
                        break;
                      }
                    argpos++;
                  }
              }

            /* Verify that the corresponding types are different for
               all the listed functions.  Also determine whether all
               the types are complex, whether all the types are
               standard or binary, and whether all the types are
               decimal.  */
            bool all_complex = true;
            bool all_binary = true;
            bool all_decimal = true;
            hash_set<tree> tg_types;
            FOR_EACH_VEC_ELT (tg_type, i, t)
              {
                if (TREE_CODE (t) == COMPLEX_TYPE)
                  all_decimal = false;
                else
                  {
                    all_complex = false;
                    if (DECIMAL_FLOAT_TYPE_P (t))
                      all_binary = false;
                    else
                      all_decimal = false;
                  }
                if (tg_types.add (t))
                  {
                    error_at ((*cexpr_list)[i].get_location (),
                              "duplicate type-generic parameter type for "
                              "function argument %u of %<__builtin_tgmath%>",
                              i + 1);
                    expr.set_error ();
                    goto out;
                  }
              }

            /* Verify that other parameters and the return type whose
               types vary have their types varying in the correct
               way.  */
            for (unsigned int j = 0; j < num_functions; j++)
              {
                tree exp_type = tg_type[j];
                tree exp_real_type = exp_type;
                if (TREE_CODE (exp_type) == COMPLEX_TYPE)
                  exp_real_type = TREE_TYPE (exp_type);
                tree type = TREE_TYPE (TREE_TYPE ((*cexpr_list)[j].value));
                tree ret = TYPE_MAIN_VARIANT (TREE_TYPE (type));
                if ((parm_kind[0] == tgmath_complex && ret != exp_type)
                    || (parm_kind[0] == tgmath_real && ret != exp_real_type))
                  {
                    error_at ((*cexpr_list)[j].get_location (),
                              "bad return type for function argument %u "
                              "of %<__builtin_tgmath%>", j + 1);
                    expr.set_error ();
                    goto out;
                  }
                argpos = 1;
                FOREACH_FUNCTION_ARGS (type, t, iter)
                  {
                    if (t == void_type_node)
                      break;
                    t = TYPE_MAIN_VARIANT (t);
                    if ((parm_kind[argpos] == tgmath_complex
                         && t != exp_type)
                        || (parm_kind[argpos] == tgmath_real
                            && t != exp_real_type))
                      {
                        error_at ((*cexpr_list)[j].get_location (),
                                  "bad type for argument %u of "
                                  "function argument %u of "
                                  "%<__builtin_tgmath%>", argpos, j + 1);
                        expr.set_error ();
                        goto out;
                      }
                    argpos++;
                  }
              }

            /* The functions listed are a valid set of functions for a
               <tgmath.h> macro to select between.  Identify the
               matching function, if any.  First, the argument types
               must be combined following <tgmath.h> rules.  Integer
               types are treated as _Decimal64 if any type-generic
               argument is decimal, or if the only alternatives for
               type-generic arguments are of decimal types, and are
               otherwise treated as _Float32x (or _Complex _Float32x
               for complex integer types) if any type-generic argument
               has _FloatNx type, otherwise as double (or _Complex
               double for complex integer types).  After that
               adjustment, types are combined following the usual
               arithmetic conversions.  If the function only accepts
               complex arguments, a complex type is produced.  */
            bool arg_complex = all_complex;
            bool arg_binary = all_binary;
            bool arg_int_decimal = all_decimal;
            bool arg_int_floatnx = false;
            for (unsigned int j = 1; j <= nargs; j++)
              {
                if (parm_kind[j] == tgmath_fixed)
                  continue;
                c_expr_t *ce = &(*cexpr_list)[num_functions + j - 1];
                tree type = TREE_TYPE (ce->value);
                if (!INTEGRAL_TYPE_P (type)
                    && !SCALAR_FLOAT_TYPE_P (type)
                    && TREE_CODE (type) != COMPLEX_TYPE)
                  {
                    error_at (ce->get_location (),
                              "invalid type of argument %u of type-generic "
                              "function", j);
                    expr.set_error ();
                    goto out;
                  }
                if (DECIMAL_FLOAT_TYPE_P (type))
                  {
                    arg_int_decimal = true;
                    if (all_complex)
                      {
                        error_at (ce->get_location (),
                                  "decimal floating-point argument %u to "
                                  "complex-only type-generic function", j);
                        expr.set_error ();
                        goto out;
                      }
                    else if (all_binary)
                      {
                        error_at (ce->get_location (),
                                  "decimal floating-point argument %u to "
                                  "binary-only type-generic function", j);
                        expr.set_error ();
                        goto out;
                      }
                    else if (arg_complex)
                      {
                        error_at (ce->get_location (),
                                  "both complex and decimal floating-point "
                                  "arguments to type-generic function");
                        expr.set_error ();
                        goto out;
                      }
                    else if (arg_binary)
                      {
                        error_at (ce->get_location (),
                                  "both binary and decimal floating-point "
                                  "arguments to type-generic function");
                        expr.set_error ();
                        goto out;
                      }
                  }
                else if (TREE_CODE (type) == COMPLEX_TYPE)
                  {
                    arg_complex = true;
                    if (COMPLEX_FLOAT_TYPE_P (type))
                      arg_binary = true;
                    if (all_decimal)
                      {
                        error_at (ce->get_location (),
                                  "complex argument %u to "
                                  "decimal-only type-generic function", j);
                        expr.set_error ();
                        goto out;
                      }
                    else if (arg_int_decimal)
                      {
                        error_at (ce->get_location (),
                                  "both complex and decimal floating-point "
                                  "arguments to type-generic function");
                        expr.set_error ();
                        goto out;
                      }
                  }
                else if (SCALAR_FLOAT_TYPE_P (type))
                  {
                    arg_binary = true;
                    if (all_decimal)
                      {
                        error_at (ce->get_location (),
                                  "binary argument %u to "
                                  "decimal-only type-generic function", j);
                        expr.set_error ();
                        goto out;
                      }
                    else if (arg_int_decimal)
                      {
                        error_at (ce->get_location (),
                                  "both binary and decimal floating-point "
                                  "arguments to type-generic function");
                        expr.set_error ();
                        goto out;
                      }
                  }
                tree rtype = TYPE_MAIN_VARIANT (type);
                if (TREE_CODE (rtype) == COMPLEX_TYPE)
                  rtype = TREE_TYPE (rtype);
                if (SCALAR_FLOAT_TYPE_P (rtype))
                  for (unsigned int j = 0; j < NUM_FLOATNX_TYPES; j++)
                    if (rtype == FLOATNX_TYPE_NODE (j))
                      {
                        arg_int_floatnx = true;
                        break;
                      }
              }
            tree arg_real = NULL_TREE;
            for (unsigned int j = 1; j <= nargs; j++)
              {
                if (parm_kind[j] == tgmath_fixed)
                  continue;
                c_expr_t *ce = &(*cexpr_list)[num_functions + j - 1];
                tree type = TYPE_MAIN_VARIANT (TREE_TYPE (ce->value));
                if (TREE_CODE (type) == COMPLEX_TYPE)
                  type = TREE_TYPE (type);
                if (INTEGRAL_TYPE_P (type))
                  type = (arg_int_decimal
                          ? dfloat64_type_node
                          : arg_int_floatnx
                          ? float32x_type_node
                          : double_type_node);
                if (arg_real == NULL_TREE)
                  arg_real = type;
                else
                  arg_real = common_type (arg_real, type);
                if (arg_real == error_mark_node)
                  {
                    expr.set_error ();
                    goto out;
                  }
              }
            tree arg_type = (arg_complex
                             ? build_complex_type (arg_real)
                             : arg_real);

            /* Look for a function to call with type-generic parameter
               type ARG_TYPE.  */
            c_expr_t *fn = NULL;
            for (unsigned int j = 0; j < num_functions; j++)
              {
                if (tg_type[j] == arg_type)
                  {
                    fn = &(*cexpr_list)[j];
                    break;
                  }
              }
            if (fn == NULL
                && parm_kind[0] == tgmath_fixed
                && SCALAR_FLOAT_TYPE_P (parm_first[0]))
              {
                /* Presume this is a macro that rounds its result to a
                   narrower type, and look for the first function with
                   at least the range and precision of the argument
                   type.  */
                for (unsigned int j = 0; j < num_functions; j++)
                  {
                    if (arg_complex
                        != (TREE_CODE (tg_type[j]) == COMPLEX_TYPE))
                      continue;
                    tree real_tg_type = (arg_complex
                                         ? TREE_TYPE (tg_type[j])
                                         : tg_type[j]);
                    if (DECIMAL_FLOAT_TYPE_P (arg_real)
                        != DECIMAL_FLOAT_TYPE_P (real_tg_type))
                      continue;
                    scalar_float_mode arg_mode
                      = SCALAR_FLOAT_TYPE_MODE (arg_real);
                    scalar_float_mode tg_mode
                      = SCALAR_FLOAT_TYPE_MODE (real_tg_type);
                    const real_format *arg_fmt = REAL_MODE_FORMAT (arg_mode);
                    const real_format *tg_fmt = REAL_MODE_FORMAT (tg_mode);
                    if (arg_fmt->b == tg_fmt->b
                        && arg_fmt->p <= tg_fmt->p
                        && arg_fmt->emax <= tg_fmt->emax
                        && (arg_fmt->emin - arg_fmt->p
                            >= tg_fmt->emin - tg_fmt->p))
                      {
                        fn = &(*cexpr_list)[j];
                        break;
                      }
                  }
              }
            if (fn == NULL)
              {
                error_at (loc, "no matching function for type-generic call");
                expr.set_error ();
                break;
              }

            /* Construct a call to FN.  */
            vec<tree, va_gc> *args;
            vec_alloc (args, nargs);
            vec<tree, va_gc> *origtypes;
            vec_alloc (origtypes, nargs);
            auto_vec<location_t> arg_loc (nargs);
            for (unsigned int j = 0; j < nargs; j++)
              {
                c_expr_t *ce = &(*cexpr_list)[num_functions + j];
                args->quick_push (ce->value);
                arg_loc.quick_push (ce->get_location ());
                origtypes->quick_push (ce->original_type);
              }
            expr.value = c_build_function_call_vec (loc, arg_loc, fn->value,
                                                    args, origtypes);
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_BUILTIN_CALL_WITH_STATIC_CHAIN:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            c_expr_t *e2_p;
            tree chain_value;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_call_with_static_chain",
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }
            if (vec_safe_length (cexpr_list) != 2)
              {
                error_at (loc, "wrong number of arguments to "
                               "%<__builtin_call_with_static_chain%>");
                expr.set_error ();
                break;
              }

            expr = (*cexpr_list)[0];
            e2_p = &(*cexpr_list)[1];
            *e2_p = convert_lvalue_to_rvalue (loc, *e2_p, true, true);
            chain_value = e2_p->value;
            mark_exp_read (chain_value);

            if (TREE_CODE (expr.value) != CALL_EXPR)
              error_at (loc, "first argument to "
                        "%<__builtin_call_with_static_chain%> "
                        "must be a call expression");
            else if (TREE_CODE (TREE_TYPE (chain_value)) != POINTER_TYPE)
              error_at (loc, "second argument to "
                        "%<__builtin_call_with_static_chain%> "
                        "must be a pointer type");
            else
              CALL_EXPR_STATIC_CHAIN (expr.value) = chain_value;
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_BUILTIN_COMPLEX:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            c_expr_t *e1_p, *e2_p;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_complex",
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            if (vec_safe_length (cexpr_list) != 2)
              {
                error_at (loc, "wrong number of arguments to "
                               "%<__builtin_complex%>");
                expr.set_error ();
                break;
              }

            e1_p = &(*cexpr_list)[0];
            e2_p = &(*cexpr_list)[1];

            *e1_p = convert_lvalue_to_rvalue (loc, *e1_p, true, true);
            if (TREE_CODE (e1_p->value) == EXCESS_PRECISION_EXPR)
              e1_p->value = convert (TREE_TYPE (e1_p->value),
                                     TREE_OPERAND (e1_p->value, 0));
            *e2_p = convert_lvalue_to_rvalue (loc, *e2_p, true, true);
            if (TREE_CODE (e2_p->value) == EXCESS_PRECISION_EXPR)
              e2_p->value = convert (TREE_TYPE (e2_p->value),
                                     TREE_OPERAND (e2_p->value, 0));
            if (!SCALAR_FLOAT_TYPE_P (TREE_TYPE (e1_p->value))
                || DECIMAL_FLOAT_TYPE_P (TREE_TYPE (e1_p->value))
                || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (e2_p->value))
                || DECIMAL_FLOAT_TYPE_P (TREE_TYPE (e2_p->value)))
              {
                error_at (loc, "%<__builtin_complex%> operand "
                          "not of real binary floating-point type");
                expr.set_error ();
                break;
              }
            if (TYPE_MAIN_VARIANT (TREE_TYPE (e1_p->value))
                != TYPE_MAIN_VARIANT (TREE_TYPE (e2_p->value)))
              {
                error_at (loc,
                          "%<__builtin_complex%> operands of different types");
                expr.set_error ();
                break;
              }
            pedwarn_c90 (loc, OPT_Wpedantic,
                         "ISO C90 does not support complex types");
            expr.value = build2_loc (loc, COMPLEX_EXPR,
                                     build_complex_type
                                     (TYPE_MAIN_VARIANT
                                      (TREE_TYPE (e1_p->value))),
                                     e1_p->value, e2_p->value);
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_BUILTIN_SHUFFLE:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            unsigned int i;
            c_expr_t *p;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_shuffle",
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            FOR_EACH_VEC_SAFE_ELT (cexpr_list, i, p)
              *p = convert_lvalue_to_rvalue (loc, *p, true, true);

            if (vec_safe_length (cexpr_list) == 2)
              expr.value = c_build_vec_perm_expr (loc, (*cexpr_list)[0].value,
                                                  NULL_TREE,
                                                  (*cexpr_list)[1].value);

            else if (vec_safe_length (cexpr_list) == 3)
              expr.value = c_build_vec_perm_expr (loc, (*cexpr_list)[0].value,
                                                  (*cexpr_list)[1].value,
                                                  (*cexpr_list)[2].value);
            else
              {
                error_at (loc, "wrong number of arguments to "
                               "%<__builtin_shuffle%>");
                expr.set_error ();
              }
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_BUILTIN_SHUFFLEVECTOR:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            unsigned int i;
            c_expr_t *p;
            location_t close_paren_loc;

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser,
                                            "__builtin_shufflevector",
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            FOR_EACH_VEC_SAFE_ELT (cexpr_list, i, p)
              *p = convert_lvalue_to_rvalue (loc, *p, true, true);

            if (vec_safe_length (cexpr_list) < 3)
              {
                error_at (loc, "wrong number of arguments to "
                               "%<__builtin_shuffle%>");
                expr.set_error ();
              }
            else
              {
                auto_vec<tree, 16> mask;
                for (i = 2; i < cexpr_list->length (); ++i)
                  mask.safe_push ((*cexpr_list)[i].value);
                expr.value = c_build_shufflevector (loc, (*cexpr_list)[0].value,
                                                    (*cexpr_list)[1].value,
                                                    mask);
              }
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            break;
          }
        case RID_BUILTIN_CONVERTVECTOR:
          {
            location_t start_loc = loc;
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            e1 = c_parser_expr_no_commas (parser, NULL);
            mark_exp_read (e1.value);
            if (!c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
              {
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                expr.set_error ();
                break;
              }
            loc = c_parser_peek_token (parser)->location;
            t1 = c_parser_type_name (parser);
            location_t end_loc = c_parser_peek_token (parser)->get_finish ();
            c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                       "expected %<)%>");
            if (t1 == NULL)
              expr.set_error ();
            else
              {
                tree type_expr = NULL_TREE;
                expr.value = c_build_vec_convert (start_loc, e1.value, loc,
                                                  groktypename (t1, &type_expr,
                                                                NULL));
                set_c_expr_source_range (&expr, start_loc, end_loc);
              }
          }
          break;
        case RID_BUILTIN_ASSOC_BARRIER:
          {
            location_t start_loc = loc;
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            e1 = c_parser_expr_no_commas (parser, NULL);
            mark_exp_read (e1.value);
            location_t end_loc = c_parser_peek_token (parser)->get_finish ();
            parens.skip_until_found_close (parser);
            expr = parser_build_unary_op (loc, PAREN_EXPR, e1);
            set_c_expr_source_range (&expr, start_loc, end_loc);
          }
          break;
        case RID_BUILTIN_STDC:
          {
            vec<c_expr_t, va_gc> *cexpr_list;
            c_expr_t *arg_p;
            location_t close_paren_loc;
            enum c_builtin_stdc {
              C_BUILTIN_STDC_BIT_CEIL,
              C_BUILTIN_STDC_BIT_FLOOR,
              C_BUILTIN_STDC_BIT_WIDTH,
              C_BUILTIN_STDC_COUNT_ONES,
              C_BUILTIN_STDC_COUNT_ZEROS,
              C_BUILTIN_STDC_FIRST_LEADING_ONE,
              C_BUILTIN_STDC_FIRST_LEADING_ZERO,
              C_BUILTIN_STDC_FIRST_TRAILING_ONE,
              C_BUILTIN_STDC_FIRST_TRAILING_ZERO,
              C_BUILTIN_STDC_HAS_SINGLE_BIT,
              C_BUILTIN_STDC_LEADING_ONES,
              C_BUILTIN_STDC_LEADING_ZEROS,
              C_BUILTIN_STDC_TRAILING_ONES,
              C_BUILTIN_STDC_TRAILING_ZEROS,
              C_BUILTIN_STDC_MAX
            } stdc_rid = C_BUILTIN_STDC_MAX;
            const char *name
              = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
            switch (name[sizeof ("__builtin_stdc_") - 1])
              {
              case 'b':
                switch (name[sizeof ("__builtin_stdc_bit_") - 1])
                  {
                  case 'c':
                    stdc_rid = C_BUILTIN_STDC_BIT_CEIL;
                    break;
                  case 'f':
                    stdc_rid = C_BUILTIN_STDC_BIT_FLOOR;
                    break;
                  default:
                    stdc_rid = C_BUILTIN_STDC_BIT_WIDTH;
                    break;
                  }
                break;
              case 'c':
                if (name[sizeof ("__builtin_stdc_count_") - 1] == 'o')
                  stdc_rid = C_BUILTIN_STDC_COUNT_ONES;
                else
                  stdc_rid = C_BUILTIN_STDC_COUNT_ZEROS;
                break;
              case 'f':
                switch (name[sizeof ("__builtin_stdc_first_trailing_") - 1])
                  {
                  case 'n':
                    stdc_rid = C_BUILTIN_STDC_FIRST_LEADING_ONE;
                    break;
                  case 'e':
                    stdc_rid = C_BUILTIN_STDC_FIRST_LEADING_ZERO;
                    break;
                  case 'o':
                    stdc_rid = C_BUILTIN_STDC_FIRST_TRAILING_ONE;
                    break;
                  default:
                    stdc_rid = C_BUILTIN_STDC_FIRST_TRAILING_ZERO;
                    break;
                  }
                break;
              case 'h':
                stdc_rid = C_BUILTIN_STDC_HAS_SINGLE_BIT;
                break;
              case 'l':
                if (name[sizeof ("__builtin_stdc_leading_") - 1] == 'o')
                  stdc_rid = C_BUILTIN_STDC_LEADING_ONES;
                else
                  stdc_rid = C_BUILTIN_STDC_LEADING_ZEROS;
                break;
              case 't':
                if (name[sizeof ("__builtin_stdc_trailing_") - 1] == 'o')
                  stdc_rid = C_BUILTIN_STDC_TRAILING_ONES;
                else
                  stdc_rid = C_BUILTIN_STDC_TRAILING_ZEROS;
                break;
              }
            gcc_checking_assert (stdc_rid != C_BUILTIN_STDC_MAX);

            c_parser_consume_token (parser);
            if (!c_parser_get_builtin_args (parser, name,
                                            &cexpr_list, false,
                                            &close_paren_loc))
              {
                expr.set_error ();
                break;
              }

            if (vec_safe_length (cexpr_list) != 1)
              {
                error_at (loc, "wrong number of arguments to %qs", name);
                expr.set_error ();
                break;
              }

            arg_p = &(*cexpr_list)[0];
            *arg_p = convert_lvalue_to_rvalue (loc, *arg_p, true, true);
            if (!INTEGRAL_TYPE_P (TREE_TYPE (arg_p->value)))
              {
                error_at (loc, "%qs operand not an integral type", name);
                expr.set_error ();
                break;
              }
            tree arg = arg_p->value;
            tree type = TYPE_MAIN_VARIANT (TREE_TYPE (arg));
            /* Expand:
               __builtin_stdc_leading_zeros (arg) as
                 (unsigned int) __builtin_clzg (arg, prec)
               __builtin_stdc_leading_ones (arg) as
                 (unsigned int) __builtin_clzg ((type) ~arg, prec)
               __builtin_stdc_trailing_zeros (arg) as
                 (unsigned int) __builtin_ctzg (arg, prec)
               __builtin_stdc_trailing_ones (arg) as
                 (unsigned int) __builtin_ctzg ((type) ~arg, prec)
               __builtin_stdc_first_leading_zero (arg) as
                 __builtin_clzg ((type) ~arg, -1) + 1U
               __builtin_stdc_first_leading_one (arg) as
                 __builtin_clzg (arg, -1) + 1U
               __builtin_stdc_first_trailing_zero (arg) as
                 __builtin_ctzg ((type) ~arg, -1) + 1U
               __builtin_stdc_first_trailing_one (arg) as
                 __builtin_ctzg (arg, -1) + 1U
               __builtin_stdc_count_zeros (arg) as
                 (unsigned int) __builtin_popcountg ((type) ~arg)
               __builtin_stdc_count_ones (arg) as
                 (unsigned int) __builtin_popcountg (arg)
               __builtin_stdc_has_single_bit (arg) as
                 (_Bool) (__builtin_popcountg (arg) == 1)
               __builtin_stdc_bit_width (arg) as
                 (unsigned int) (prec - __builtin_clzg (arg, prec))
               __builtin_stdc_bit_floor (arg) as
                 arg == 0 ? (type) 0
                          : (type) 1 << (prec - 1 - __builtin_clzg (arg))
               __builtin_stdc_bit_ceil (arg) as
                 arg <= 1 ? (type) 1
                          : (type) 2 << (prec - 1 - __builtin_clzg (arg - 1))
               without evaluating arg multiple times, type being
               __typeof (arg) and prec __builtin_popcountg ((type) ~0)).  */
            int prec = TYPE_PRECISION (type);
            tree barg1 = arg;
            switch (stdc_rid)
              {
              case C_BUILTIN_STDC_BIT_CEIL:
                arg = save_expr (arg);
                barg1 = build2_loc (loc, PLUS_EXPR, type, arg,
                                    build_int_cst (type, -1));
                break;
              case C_BUILTIN_STDC_BIT_FLOOR:
                barg1 = arg = save_expr (arg);
                break;
              case C_BUILTIN_STDC_COUNT_ZEROS:
              case C_BUILTIN_STDC_FIRST_LEADING_ZERO:
              case C_BUILTIN_STDC_FIRST_TRAILING_ZERO:
              case C_BUILTIN_STDC_LEADING_ONES:
              case C_BUILTIN_STDC_TRAILING_ONES:
                barg1 = build1_loc (loc, BIT_NOT_EXPR, type, arg);
                break;
              default:
                break;
              }
            tree barg2 = NULL_TREE;
            switch (stdc_rid)
              {
              case C_BUILTIN_STDC_BIT_WIDTH:
              case C_BUILTIN_STDC_LEADING_ONES:
              case C_BUILTIN_STDC_LEADING_ZEROS:
              case C_BUILTIN_STDC_TRAILING_ONES:
              case C_BUILTIN_STDC_TRAILING_ZEROS:
                barg2 = build_int_cst (integer_type_node, prec);
                break;
              case C_BUILTIN_STDC_FIRST_LEADING_ONE:
              case C_BUILTIN_STDC_FIRST_LEADING_ZERO:
              case C_BUILTIN_STDC_FIRST_TRAILING_ONE:
              case C_BUILTIN_STDC_FIRST_TRAILING_ZERO:
                barg2 = integer_minus_one_node;
                break;
              default:
                break;
              }
            tree fndecl = NULL_TREE;
            switch (stdc_rid)
              {
              case C_BUILTIN_STDC_BIT_CEIL:
              case C_BUILTIN_STDC_BIT_FLOOR:
              case C_BUILTIN_STDC_BIT_WIDTH:
              case C_BUILTIN_STDC_FIRST_LEADING_ONE:
              case C_BUILTIN_STDC_FIRST_LEADING_ZERO:
              case C_BUILTIN_STDC_LEADING_ONES:
              case C_BUILTIN_STDC_LEADING_ZEROS:
                fndecl = builtin_decl_explicit (BUILT_IN_CLZG);
                break;
              case C_BUILTIN_STDC_FIRST_TRAILING_ONE:
              case C_BUILTIN_STDC_FIRST_TRAILING_ZERO:
              case C_BUILTIN_STDC_TRAILING_ONES:
              case C_BUILTIN_STDC_TRAILING_ZEROS:
                fndecl = builtin_decl_explicit (BUILT_IN_CTZG);
                break;
              case C_BUILTIN_STDC_COUNT_ONES:
              case C_BUILTIN_STDC_COUNT_ZEROS:
              case C_BUILTIN_STDC_HAS_SINGLE_BIT:
                fndecl = builtin_decl_explicit (BUILT_IN_POPCOUNTG);
                break;
              default:
                gcc_unreachable ();
              }
            /* Construct a call to __builtin_{clz,ctz,popcount}g.  */
            int nargs = barg2 != NULL_TREE ? 2 : 1;
            vec<tree, va_gc> *args;
            vec_alloc (args, nargs);
            vec<tree, va_gc> *origtypes;
            vec_alloc (origtypes, nargs);
            auto_vec<location_t> arg_loc (nargs);
            args->quick_push (barg1);
            arg_loc.quick_push (arg_p->get_location ());
            origtypes->quick_push (arg_p->original_type);
            if (nargs == 2)
              {
                args->quick_push (barg2);
                arg_loc.quick_push (loc);
                origtypes->quick_push (integer_type_node);
              }
            expr.value = c_build_function_call_vec (loc, arg_loc, fndecl,
                                                    args, origtypes);
            set_c_expr_source_range (&expr, loc, close_paren_loc);
            if (expr.value == error_mark_node)
              break;
            switch (stdc_rid)
              {
              case C_BUILTIN_STDC_BIT_CEIL:
              case C_BUILTIN_STDC_BIT_FLOOR:
                --prec;
                /* FALLTHRU */
              case C_BUILTIN_STDC_BIT_WIDTH:
                expr.value = build2_loc (loc, MINUS_EXPR, integer_type_node,
                                         build_int_cst (integer_type_node,
                                                        prec), expr.value);
                break;
              case C_BUILTIN_STDC_FIRST_LEADING_ONE:
              case C_BUILTIN_STDC_FIRST_LEADING_ZERO:
              case C_BUILTIN_STDC_FIRST_TRAILING_ONE:
              case C_BUILTIN_STDC_FIRST_TRAILING_ZERO:
                expr.value = build2_loc (loc, PLUS_EXPR, integer_type_node,
                                         expr.value, integer_one_node);
                break;
              case C_BUILTIN_STDC_HAS_SINGLE_BIT:
                expr.value = build2_loc (loc, EQ_EXPR, boolean_type_node,
                                         expr.value, integer_one_node);
                break;
              default:
                break;
              }

            if (stdc_rid != C_BUILTIN_STDC_BIT_CEIL
                && stdc_rid != C_BUILTIN_STDC_BIT_FLOOR)
              {
                if (stdc_rid != C_BUILTIN_STDC_HAS_SINGLE_BIT)
                  expr.value = fold_convert_loc (loc, unsigned_type_node,
                                                 expr.value);
                break;
              }
            /* For __builtin_stdc_bit_ceil (0U) or __builtin_stdc_bit_ceil (1U)
               or __builtin_stdc_bit_floor (0U) avoid bogus -Wshift-count-*
               warnings.  The LSHIFT_EXPR is in dead code in that case.  */
            if (integer_zerop (arg)
                || (stdc_rid == C_BUILTIN_STDC_BIT_CEIL && integer_onep (arg)))
              expr.value = build_int_cst (type, 0);
            else
              expr.value
                = build2_loc (loc, LSHIFT_EXPR, type,
                              build_int_cst (type,
                                             (stdc_rid
                                              == C_BUILTIN_STDC_BIT_CEIL
                                              ? 2 : 1)), expr.value);
            if (stdc_rid == C_BUILTIN_STDC_BIT_CEIL)
              expr.value = build3_loc (loc, COND_EXPR, type,
                                       build2_loc (loc, LE_EXPR,
                                                   boolean_type_node, arg,
                                                   build_int_cst (type, 1)),
                                       build_int_cst (type, 1),
                                       expr.value);
            else
              expr.value = build3_loc (loc, COND_EXPR, type,
                                       build2_loc (loc, EQ_EXPR,
                                                   boolean_type_node, arg,
                                                   build_int_cst (type, 0)),
                                       build_int_cst (type, 0),
                                       expr.value);
            break;
          }
        case RID_AT_SELECTOR:
          {
            gcc_assert (c_dialect_objc ());
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            tree sel = c_parser_objc_selector_arg (parser);
            location_t close_loc = c_parser_peek_token (parser)->location;
            parens.skip_until_found_close (parser);
            expr.value = objc_build_selector_expr (loc, sel);
            set_c_expr_source_range (&expr, loc, close_loc);
          }
          break;
        case RID_AT_PROTOCOL:
          {
            gcc_assert (c_dialect_objc ());
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            if (c_parser_next_token_is_not (parser, CPP_NAME))
              {
                c_parser_error (parser, "expected identifier");
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                expr.set_error ();
                break;
              }
            tree id = c_parser_peek_token (parser)->value;
            c_parser_consume_token (parser);
            location_t close_loc = c_parser_peek_token (parser)->location;
            parens.skip_until_found_close (parser);
            expr.value = objc_build_protocol_expr (id);
            set_c_expr_source_range (&expr, loc, close_loc);
          }
          break;
        case RID_AT_ENCODE:
          {
            /* Extension to support C-structures in the archiver.  */
            gcc_assert (c_dialect_objc ());
            c_parser_consume_token (parser);
            matching_parens parens;
            if (!parens.require_open (parser))
              {
                expr.set_error ();
                break;
              }
            t1 = c_parser_type_name (parser);
            if (t1 == NULL)
              {
                expr.set_error ();
                c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
                break;
              }
            location_t close_loc = c_parser_peek_token (parser)->location;
            parens.skip_until_found_close (parser);
            tree type = groktypename (t1, NULL, NULL);
            expr.value = objc_build_encode_expr (type);
            set_c_expr_source_range (&expr, loc, close_loc);
          }
          break;
        case RID_GENERIC:
          expr = c_parser_generic_selection (parser);
          break;
        case RID_OMP_ALL_MEMORY:
          gcc_assert (flag_openmp);
          c_parser_consume_token (parser);
          error_at (loc, "%<omp_all_memory%> may only be used in OpenMP "
                         "%<depend%> clause");
          expr.set_error ();
          break;
        /* C23 'nullptr' literal.  */
        case RID_NULLPTR:
          c_parser_consume_token (parser);
          expr.value = nullptr_node;
          set_c_expr_source_range (&expr, tok_range);
          pedwarn_c11 (loc, OPT_Wpedantic,
                       "ISO C does not support %qs before C23", "nullptr");
          break;
        case RID_TRUE:
          c_parser_consume_token (parser);
          expr.value = boolean_true_node;
          set_c_expr_source_range (&expr, tok_range);
          break;
        case RID_FALSE:
          c_parser_consume_token (parser);
          expr.value = boolean_false_node;
          set_c_expr_source_range (&expr, tok_range);
          break;
        default:
          c_parser_error (parser, "expected expression");
          expr.set_error ();
          break;
        }
      break;
    case CPP_OPEN_SQUARE:
      if (c_dialect_objc ())
        {
          tree receiver, args;
          c_parser_consume_token (parser);
          receiver = c_parser_objc_receiver (parser);
          args = c_parser_objc_message_args (parser);
          location_t close_loc = c_parser_peek_token (parser)->location;
          c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                     "expected %<]%>");
          expr.value = objc_build_message_expr (receiver, args);
          set_c_expr_source_range (&expr, loc, close_loc);
          break;
        }
      /* Else fall through to report error.  */
      /* FALLTHRU */
    default:
      c_parser_error (parser, "expected expression");
      expr.set_error ();
      break;
    }
 out:
  return c_parser_postfix_expression_after_primary
    (parser, EXPR_LOC_OR_LOC (expr.value, loc), expr);
}

/* Parse a postfix expression after a parenthesized type name: the
   brace-enclosed initializer of a compound literal, possibly followed
   by some postfix operators.  This is separate because it is not
   possible to tell until after the type name whether a cast
   expression has a cast or a compound literal, or whether the operand
   of sizeof is a parenthesized type name or starts with a compound
   literal.  TYPE_LOC is the location where TYPE_NAME starts--the
   location of the first token after the parentheses around the type
   name.  */

static struct c_expr
c_parser_postfix_expression_after_paren_type (c_parser *parser,
                                              struct c_declspecs *scspecs,
                                              struct c_type_name *type_name,
                                              location_t type_loc)
{
  tree type;
  struct c_expr init;
  bool non_const;
  struct c_expr expr;
  location_t start_loc;
  tree type_expr = NULL_TREE;
  bool type_expr_const = true;
  bool constexpr_p = scspecs ? scspecs->constexpr_p : false;
  unsigned int underspec_state = 0;
  check_compound_literal_type (type_loc, type_name);
  rich_location richloc (line_table, type_loc);
  start_loc = c_parser_peek_token (parser)->location;
  if (constexpr_p)
    {
      underspec_state = start_underspecified_init (start_loc, NULL_TREE);
      /* A constexpr compound literal is subject to the constraints on
         underspecified declarations, which may not declare tags or
         members or structures or unions; it is undefined behavior to
         declare the members of an enumeration.  Where the structure,
         union or enumeration type is declared within the compound
         literal initializer, this is diagnosed elsewhere as a result
         of the above call to start_underspecified_init.  Diagnose
         here the case of declaring such a type in the type specifiers
         of the compound literal.  */
      switch (type_name->specs->typespec_kind)
        {
        case ctsk_tagfirstref:
        case ctsk_tagfirstref_attrs:
          error_at (type_loc, "%qT declared in %<constexpr%> compound literal",
                    type_name->specs->type);
          break;

        case ctsk_tagdef:
          error_at (type_loc, "%qT defined in %<constexpr%> compound literal",
                    type_name->specs->type);
          break;

        default:
          break;
        }
    }
  start_init (NULL_TREE, NULL,
              (global_bindings_p ()
               || (scspecs && scspecs->storage_class == csc_static)
               || constexpr_p), constexpr_p, &richloc);
  type = groktypename (type_name, &type_expr, &type_expr_const);
  if (type != error_mark_node && C_TYPE_VARIABLE_SIZE (type))
    {
      error_at (type_loc, "compound literal has variable size");
      type = error_mark_node;
    }
  else if (TREE_CODE (type) == FUNCTION_TYPE)
    {
      error_at (type_loc, "compound literal has function type");
      type = error_mark_node;
    }
  if (constexpr_p && type != error_mark_node)
    {
      tree type_no_array = strip_array_types (type);
      /* The type of a constexpr object must not be variably modified
         (which applies to all compound literals), volatile, atomic or
         restrict qualified or have a member with such a qualifier.
         const qualification is implicitly added.  */
      if (TYPE_QUALS (type_no_array)
          & (TYPE_QUAL_VOLATILE | TYPE_QUAL_RESTRICT | TYPE_QUAL_ATOMIC))
        error_at (type_loc, "invalid qualifiers for %<constexpr%> object");
      else if (RECORD_OR_UNION_TYPE_P (type_no_array)
               && C_TYPE_FIELDS_NON_CONSTEXPR (type_no_array))
        error_at (type_loc, "invalid qualifiers for field of "
                  "%<constexpr%> object");
      type = c_build_qualified_type (type,
                                     (TYPE_QUALS (type_no_array)
                                      | TYPE_QUAL_CONST));
    }
  init = c_parser_braced_init (parser, type, false, NULL, NULL_TREE);
  if (constexpr_p)
    finish_underspecified_init (NULL_TREE, underspec_state);
  finish_init ();
  maybe_warn_string_init (type_loc, type, init);

  if (type != error_mark_node
      && !ADDR_SPACE_GENERIC_P (TYPE_ADDR_SPACE (type))
      && current_function_decl)
    {
      error ("compound literal qualified by address-space qualifier");
      type = error_mark_node;
    }

  if (!pedwarn_c90 (start_loc, OPT_Wpedantic,
                    "ISO C90 forbids compound literals") && scspecs)
    pedwarn_c11 (start_loc, OPT_Wpedantic,
                 "ISO C forbids storage class specifiers in compound literals "
                 "before C23");
  non_const = ((init.value && TREE_CODE (init.value) == CONSTRUCTOR)
               ? CONSTRUCTOR_NON_CONST (init.value)
               : init.original_code == C_MAYBE_CONST_EXPR);
  non_const |= !type_expr_const;
  unsigned int alignas_align = 0;
  if (type != error_mark_node
      && type_name->specs->align_log != -1)
    {
      alignas_align = 1U << type_name->specs->align_log;
      if (alignas_align < min_align_of_type (type))
        {
          error_at (type_name->specs->locations[cdw_alignas],
                    "%<_Alignas%> specifiers cannot reduce "
                    "alignment of compound literal");
          alignas_align = 0;
        }
    }
  expr.value = build_compound_literal (start_loc, type, init.value, non_const,
                                       alignas_align, scspecs);
  set_c_expr_source_range (&expr, init.src_range);
  expr.m_decimal = 0;
  expr.original_code = ERROR_MARK;
  expr.original_type = NULL;
  if (type != error_mark_node
      && expr.value != error_mark_node
      && type_expr)
    {
      if (TREE_CODE (expr.value) == C_MAYBE_CONST_EXPR)
        {
          gcc_assert (C_MAYBE_CONST_EXPR_PRE (expr.value) == NULL_TREE);
          C_MAYBE_CONST_EXPR_PRE (expr.value) = type_expr;
        }
      else
        {
          gcc_assert (!non_const);
          expr.value = build2 (C_MAYBE_CONST_EXPR, type,
                               type_expr, expr.value);
        }
    }
  return c_parser_postfix_expression_after_primary (parser, start_loc, expr);
}

/* Callback function for sizeof_pointer_memaccess_warning to compare
   types.  */

static bool
sizeof_ptr_memacc_comptypes (tree type1, tree type2)
{
  return comptypes (type1, type2) == 1;
}

/* Warn for patterns where abs-like function appears to be used incorrectly,
   gracefully ignore any non-abs-like function.  The warning location should
   be LOC.  FNDECL is the declaration of called function, it must be a
   BUILT_IN_NORMAL function.  ARG is the first and only argument of the
   call.  */

static void
warn_for_abs (location_t loc, tree fndecl, tree arg)
{
  /* Avoid warning in unreachable subexpressions.  */
  if (c_inhibit_evaluation_warnings)
    return;

  tree atype = TREE_TYPE (arg);

  /* Casts from pointers (and thus arrays and fndecls) will generate
     -Wint-conversion warnings.  Most other wrong types hopefully lead to type
     mismatch errors.  TODO: Think about what to do with FIXED_POINT_TYPE_P
     types and possibly other exotic types.  */
  if (!INTEGRAL_TYPE_P (atype)
      && !SCALAR_FLOAT_TYPE_P (atype)
      && TREE_CODE (atype) != COMPLEX_TYPE)
    return;

  enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);

  switch (fcode)
    {
    case BUILT_IN_ABS:
    case BUILT_IN_LABS:
    case BUILT_IN_LLABS:
    case BUILT_IN_IMAXABS:
      if (!INTEGRAL_TYPE_P (atype))
        {
          if (SCALAR_FLOAT_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using integer absolute value function %qD when "
                        "argument is of floating-point type %qT",
                        fndecl, atype);
          else if (TREE_CODE (atype) == COMPLEX_TYPE)
            warning_at (loc, OPT_Wabsolute_value,
                        "using integer absolute value function %qD when "
                        "argument is of complex type %qT", fndecl, atype);
          else
            gcc_unreachable ();
          return;
        }
      if (TYPE_UNSIGNED (atype))
        warning_at (loc, OPT_Wabsolute_value,
                    "taking the absolute value of unsigned type %qT "
                    "has no effect", atype);
      break;

    CASE_FLT_FN (BUILT_IN_FABS):
    CASE_FLT_FN_FLOATN_NX (BUILT_IN_FABS):
      if (!SCALAR_FLOAT_TYPE_P (atype)
          || DECIMAL_FLOAT_MODE_P (TYPE_MODE (atype)))
        {
          if (INTEGRAL_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using floating-point absolute value function %qD "
                        "when argument is of integer type %qT", fndecl, atype);
          else if (DECIMAL_FLOAT_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using floating-point absolute value function %qD "
                        "when argument is of decimal floating-point type %qT",
                        fndecl, atype);
          else if (TREE_CODE (atype) == COMPLEX_TYPE)
            warning_at (loc, OPT_Wabsolute_value,
                        "using floating-point absolute value function %qD when "
                        "argument is of complex type %qT", fndecl, atype);
          else
            gcc_unreachable ();
          return;
        }
      break;

    CASE_FLT_FN (BUILT_IN_CABS):
      if (TREE_CODE (atype) != COMPLEX_TYPE)
        {
          if (INTEGRAL_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using complex absolute value function %qD when "
                        "argument is of integer type %qT", fndecl, atype);
          else if (SCALAR_FLOAT_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using complex absolute value function %qD when "
                        "argument is of floating-point type %qT",
                        fndecl, atype);
          else
            gcc_unreachable ();

          return;
        }
      break;

    case BUILT_IN_FABSD32:
    case BUILT_IN_FABSD64:
    case BUILT_IN_FABSD128:
      if (!DECIMAL_FLOAT_TYPE_P (atype))
        {
          if (INTEGRAL_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using decimal floating-point absolute value "
                        "function %qD when argument is of integer type %qT",
                        fndecl, atype);
          else if (SCALAR_FLOAT_TYPE_P (atype))
            warning_at (loc, OPT_Wabsolute_value,
                        "using decimal floating-point absolute value "
                        "function %qD when argument is of floating-point "
                        "type %qT", fndecl, atype);
          else if (TREE_CODE (atype) == COMPLEX_TYPE)
            warning_at (loc, OPT_Wabsolute_value,
                        "using decimal floating-point absolute value "
                        "function %qD when argument is of complex type %qT",
                        fndecl, atype);
          else
            gcc_unreachable ();
          return;
        }
      break;

    default:
      return;
    }

  if (!TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
    return;

  tree ftype = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
  if (TREE_CODE (atype) == COMPLEX_TYPE)
    {
      gcc_assert (TREE_CODE (ftype) == COMPLEX_TYPE);
      atype = TREE_TYPE (atype);
      ftype = TREE_TYPE (ftype);
    }

  if (TYPE_PRECISION (ftype) < TYPE_PRECISION (atype))
    warning_at (loc, OPT_Wabsolute_value,
                "absolute value function %qD given an argument of type %qT "
                "but has parameter of type %qT which may cause truncation "
                "of value", fndecl, atype, ftype);
}


/* Parse a postfix expression after the initial primary or compound
   literal; that is, parse a series of postfix operators.

   EXPR_LOC is the location of the primary expression.  */

static struct c_expr
c_parser_postfix_expression_after_primary (c_parser *parser,
                                           location_t expr_loc,
                                           struct c_expr expr)
{
  struct c_expr orig_expr;
  tree ident, idx, len;
  location_t sizeof_arg_loc[6], comp_loc;
  tree sizeof_arg[6];
  unsigned int literal_zero_mask;
  unsigned int i;
  vec<tree, va_gc> *exprlist;
  vec<tree, va_gc> *origtypes = NULL;
  vec<location_t> arg_loc = vNULL;
  location_t start;
  location_t finish;

  while (true)
    {
      location_t op_loc = c_parser_peek_token (parser)->location;
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_OPEN_SQUARE:
          /* Array reference.  */
          c_parser_consume_token (parser);
          idx = len = NULL_TREE;
          if (!c_omp_array_section_p
              || c_parser_next_token_is_not (parser, CPP_COLON))
            idx = c_parser_expression (parser).value;

          if (c_omp_array_section_p
              && c_parser_next_token_is (parser, CPP_COLON))
            {
              c_parser_consume_token (parser);
              if (c_parser_next_token_is_not (parser, CPP_CLOSE_SQUARE))
                len = c_parser_expression (parser).value;

              expr.value = build_omp_array_section (op_loc, expr.value, idx,
                                                    len);
            }
          else
            expr.value = build_array_ref (op_loc, expr.value, idx);

          c_parser_skip_until_found (parser, CPP_CLOSE_SQUARE,
                                     "expected %<]%>");

          start = expr.get_start ();
          finish = parser->tokens_buf[0].location;
          set_c_expr_source_range (&expr, start, finish);
          expr.original_code = ERROR_MARK;
          expr.original_type = NULL;
          expr.m_decimal = 0;
          break;
        case CPP_OPEN_PAREN:
          /* Function call.  */
          {
            matching_parens parens;
            parens.consume_open (parser);
            for (i = 0; i < 6; i++)
              {
                sizeof_arg[i] = NULL_TREE;
                sizeof_arg_loc[i] = UNKNOWN_LOCATION;
              }
            literal_zero_mask = 0;
            if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
              exprlist = NULL;
            else if (TREE_CODE (expr.value) == FUNCTION_DECL
                     && fndecl_built_in_p (expr.value, BUILT_IN_CLASSIFY_TYPE)
                     && c_parser_next_tokens_start_typename (parser,
                                                             cla_prefer_id))
              {
                /* __builtin_classify_type (type)  */
                c_inhibit_evaluation_warnings++;
                in_alignof++;
                struct c_type_name *type = c_parser_type_name (parser);
                c_inhibit_evaluation_warnings--;
                in_alignof--;
                struct c_typespec ret;
                ret.expr = NULL_TREE;
                ret.spec = error_mark_node;
                ret.expr_const_operands = false;
                if (type != NULL)
                  ret.spec = groktypename (type, &ret.expr,
                                           &ret.expr_const_operands);
                parens.skip_until_found_close (parser);
                expr.value = build_int_cst (integer_type_node,
                                            type_to_class (ret.spec));
                break;
              }
            else
              exprlist = c_parser_expr_list (parser, true, false, &origtypes,
                                             sizeof_arg_loc, sizeof_arg,
                                             &arg_loc, &literal_zero_mask);
            parens.skip_until_found_close (parser);
          }
          orig_expr = expr;
          mark_exp_read (expr.value);
          if (warn_sizeof_pointer_memaccess)
            sizeof_pointer_memaccess_warning (sizeof_arg_loc,
                                              expr.value, exprlist,
                                              sizeof_arg,
                                              sizeof_ptr_memacc_comptypes);
          if (TREE_CODE (expr.value) == FUNCTION_DECL)
            {
              if (fndecl_built_in_p (expr.value, BUILT_IN_MEMSET)
                  && vec_safe_length (exprlist) == 3)
                {
                  tree arg0 = (*exprlist)[0];
                  tree arg2 = (*exprlist)[2];
                  warn_for_memset (expr_loc, arg0, arg2, literal_zero_mask);
                }
              if (warn_absolute_value
                  && fndecl_built_in_p (expr.value, BUILT_IN_NORMAL)
                  && vec_safe_length (exprlist) == 1)
                warn_for_abs (expr_loc, expr.value, (*exprlist)[0]);
              if (parser->omp_for_parse_state
                  && parser->omp_for_parse_state->in_intervening_code
                  && omp_runtime_api_call (expr.value))
                {
                  error_at (expr_loc, "calls to the OpenMP runtime API are "
                                      "not permitted in intervening code");
                  parser->omp_for_parse_state->fail = true;
                }
              if (warn_calloc_transposed_args)
                if (tree attr = lookup_attribute ("alloc_size",
                                                  TYPE_ATTRIBUTES
                                                    (TREE_TYPE (expr.value))))
                  if (TREE_VALUE (attr) && TREE_CHAIN (TREE_VALUE (attr)))
                    warn_for_calloc (sizeof_arg_loc, expr.value, exprlist,
                                     sizeof_arg, attr);
            }

          start = expr.get_start ();
          finish = parser->tokens_buf[0].get_finish ();
          expr.value
            = c_build_function_call_vec (expr_loc, arg_loc, expr.value,
                                         exprlist, origtypes);
          set_c_expr_source_range (&expr, start, finish);
          expr.m_decimal = 0;

          expr.original_code = ERROR_MARK;
          if (TREE_CODE (expr.value) == INTEGER_CST
              && TREE_CODE (orig_expr.value) == FUNCTION_DECL
              && fndecl_built_in_p (orig_expr.value, BUILT_IN_CONSTANT_P))
            expr.original_code = C_MAYBE_CONST_EXPR;
          expr.original_type = NULL;
          if (exprlist)
            {
              release_tree_vector (exprlist);
              release_tree_vector (origtypes);
            }
          arg_loc.release ();
          break;
        case CPP_DOT:
          /* Structure element reference.  */
          c_parser_consume_token (parser);
          expr = default_function_array_conversion (expr_loc, expr);
          if (c_parser_next_token_is (parser, CPP_NAME))
            {
              c_token *comp_tok = c_parser_peek_token (parser);
              ident = comp_tok->value;
              comp_loc = comp_tok->location;
            }
          else
            {
              c_parser_error (parser, "expected identifier");
              expr.set_error ();
              expr.original_code = ERROR_MARK;
              expr.original_type = NULL;
              return expr;
            }
          start = expr.get_start ();
          finish = c_parser_peek_token (parser)->get_finish ();
          c_parser_consume_token (parser);
          expr.value = build_component_ref (op_loc, expr.value, ident,
                                            comp_loc, UNKNOWN_LOCATION);
          set_c_expr_source_range (&expr, start, finish);
          expr.original_code = ERROR_MARK;
          if (TREE_CODE (expr.value) != COMPONENT_REF)
            expr.original_type = NULL;
          else
            {
              /* Remember the original type of a bitfield.  */
              tree field = TREE_OPERAND (expr.value, 1);
              if (TREE_CODE (field) != FIELD_DECL)
                expr.original_type = NULL;
              else
                expr.original_type = DECL_BIT_FIELD_TYPE (field);
            }
          expr.m_decimal = 0;
          break;
        case CPP_DEREF:
          /* Structure element reference.  */
          c_parser_consume_token (parser);
          expr = convert_lvalue_to_rvalue (expr_loc, expr, true, false);
          if (c_parser_next_token_is (parser, CPP_NAME))
            {
              c_token *comp_tok = c_parser_peek_token (parser);
              ident = comp_tok->value;
              comp_loc = comp_tok->location;
            }
          else
            {
              c_parser_error (parser, "expected identifier");
              expr.set_error ();
              expr.original_code = ERROR_MARK;
              expr.original_type = NULL;
              return expr;
            }
          start = expr.get_start ();
          finish = c_parser_peek_token (parser)->get_finish ();
          c_parser_consume_token (parser);
          expr.value = build_component_ref (op_loc,
                                            build_indirect_ref (op_loc,
                                                                expr.value,
                                                                RO_ARROW),
                                            ident, comp_loc,
                                            expr.get_location ());
          set_c_expr_source_range (&expr, start, finish);
          expr.original_code = ERROR_MARK;
          if (TREE_CODE (expr.value) != COMPONENT_REF)
            expr.original_type = NULL;
          else
            {
              /* Remember the original type of a bitfield.  */
              tree field = TREE_OPERAND (expr.value, 1);
              if (TREE_CODE (field) != FIELD_DECL)
                expr.original_type = NULL;
              else
                expr.original_type = DECL_BIT_FIELD_TYPE (field);
            }
          expr.m_decimal = 0;
          break;
        case CPP_PLUS_PLUS:
          /* Postincrement.  */
          start = expr.get_start ();
          finish = c_parser_peek_token (parser)->get_finish ();
          c_parser_consume_token (parser);
          expr = default_function_array_read_conversion (expr_loc, expr);
          expr.value = build_unary_op (op_loc, POSTINCREMENT_EXPR,
                                       expr.value, false);
          set_c_expr_source_range (&expr, start, finish);
          expr.original_code = ERROR_MARK;
          expr.original_type = NULL;
          break;
        case CPP_MINUS_MINUS:
          /* Postdecrement.  */
          start = expr.get_start ();
          finish = c_parser_peek_token (parser)->get_finish ();
          c_parser_consume_token (parser);
          expr = default_function_array_read_conversion (expr_loc, expr);
          expr.value = build_unary_op (op_loc, POSTDECREMENT_EXPR,
                                       expr.value, false);
          set_c_expr_source_range (&expr, start, finish);
          expr.original_code = ERROR_MARK;
          expr.original_type = NULL;
          break;
        default:
          return expr;
        }
    }
}

/* Parse an expression (C90 6.3.17, C99 6.5.17, C11 6.5.17).

   expression:
     assignment-expression
     expression , assignment-expression
*/

static struct c_expr
c_parser_expression (c_parser *parser)
{
  location_t tloc = c_parser_peek_token (parser)->location;
  struct c_expr expr;
  expr = c_parser_expr_no_commas (parser, NULL);
  if (c_parser_next_token_is (parser, CPP_COMMA))
    expr = convert_lvalue_to_rvalue (tloc, expr, true, false);
  while (c_parser_next_token_is (parser, CPP_COMMA))
    {
      struct c_expr next;
      tree lhsval;
      location_t loc = c_parser_peek_token (parser)->location;
      location_t expr_loc;
      c_parser_consume_token (parser);
      expr_loc = c_parser_peek_token (parser)->location;
      lhsval = expr.value;
      while (TREE_CODE (lhsval) == COMPOUND_EXPR
             || TREE_CODE (lhsval) == NOP_EXPR)
        {
          if (TREE_CODE (lhsval) == COMPOUND_EXPR)
            lhsval = TREE_OPERAND (lhsval, 1);
          else
            lhsval = TREE_OPERAND (lhsval, 0);
        }
      if (DECL_P (lhsval) || handled_component_p (lhsval))
        mark_exp_read (lhsval);
      next = c_parser_expr_no_commas (parser, NULL);
      next = convert_lvalue_to_rvalue (expr_loc, next, true, false);
      expr.value = build_compound_expr (loc, expr.value, next.value);
      expr.original_code = COMPOUND_EXPR;
      expr.original_type = next.original_type;
      expr.m_decimal = 0;
    }
  return expr;
}

/* Parse an expression and convert functions or arrays to pointers and
   lvalues to rvalues.  */

static struct c_expr
c_parser_expression_conv (c_parser *parser)
{
  struct c_expr expr;
  location_t loc = c_parser_peek_token (parser)->location;
  expr = c_parser_expression (parser);
  expr = convert_lvalue_to_rvalue (loc, expr, true, false);
  return expr;
}

/* Helper function of c_parser_expr_list.  Check if IDXth (0 based)
   argument is a literal zero alone and if so, set it in literal_zero_mask.  */

static inline void
c_parser_check_literal_zero (c_parser *parser, unsigned *literal_zero_mask,
                             unsigned int idx)
{
  if (idx >= HOST_BITS_PER_INT)
    return;

  c_token *tok = c_parser_peek_token (parser);
  switch (tok->type)
    {
    case CPP_NUMBER:
    case CPP_CHAR:
    case CPP_WCHAR:
    case CPP_CHAR16:
    case CPP_CHAR32:
    case CPP_UTF8CHAR:
      /* If a parameter is literal zero alone, remember it
         for -Wmemset-transposed-args warning.  */
      if (integer_zerop (tok->value)
          && !TREE_OVERFLOW (tok->value)
          && (c_parser_peek_2nd_token (parser)->type == CPP_COMMA
              || c_parser_peek_2nd_token (parser)->type == CPP_CLOSE_PAREN))
        *literal_zero_mask |= 1U << idx;
    default:
      break;
    }
}

/* Parse a non-empty list of expressions.  If CONVERT_P, convert
   functions and arrays to pointers and lvalues to rvalues.  If
   FOLD_P, fold the expressions.  If LOCATIONS is non-NULL, save the
   locations of function arguments into this vector.

   nonempty-expr-list:
     assignment-expression
     nonempty-expr-list , assignment-expression
*/

static vec<tree, va_gc> *
c_parser_expr_list (c_parser *parser, bool convert_p, bool fold_p,
                    vec<tree, va_gc> **p_orig_types,
                    location_t *sizeof_arg_loc, tree *sizeof_arg,
                    vec<location_t> *locations,
                    unsigned int *literal_zero_mask)
{
  vec<tree, va_gc> *ret;
  vec<tree, va_gc> *orig_types;
  struct c_expr expr;
  unsigned int idx = 0;
  bool save_c_omp_array_section_p = c_omp_array_section_p;
  c_omp_array_section_p = false;

  ret = make_tree_vector ();
  if (p_orig_types == NULL)
    orig_types = NULL;
  else
    orig_types = make_tree_vector ();

  if (literal_zero_mask)
    c_parser_check_literal_zero (parser, literal_zero_mask, 0);
  expr = c_parser_expr_no_commas (parser, NULL);
  if (convert_p)
    expr = convert_lvalue_to_rvalue (expr.get_location (), expr, true, true);
  if (fold_p)
    expr.value = c_fully_fold (expr.value, false, NULL);
  ret->quick_push (expr.value);
  if (orig_types)
    orig_types->quick_push (expr.original_type);
  if (locations)
    locations->safe_push (expr.get_location ());
  if (sizeof_arg != NULL
      && (expr.original_code == SIZEOF_EXPR
          || expr.original_code == PAREN_SIZEOF_EXPR))
    {
      sizeof_arg[0] = c_last_sizeof_arg;
      sizeof_arg_loc[0] = c_last_sizeof_loc;
    }
  while (c_parser_next_token_is (parser, CPP_COMMA))
    {
      c_parser_consume_token (parser);
      if (literal_zero_mask)
        c_parser_check_literal_zero (parser, literal_zero_mask, idx + 1);
      expr = c_parser_expr_no_commas (parser, NULL);
      if (convert_p)
        expr = convert_lvalue_to_rvalue (expr.get_location (), expr, true,
                                         true);
      if (fold_p)
        expr.value = c_fully_fold (expr.value, false, NULL);
      vec_safe_push (ret, expr.value);
      if (orig_types)
        vec_safe_push (orig_types, expr.original_type);
      if (locations)
        locations->safe_push (expr.get_location ());
      if (++idx < 6
          && sizeof_arg != NULL
          && (expr.original_code == SIZEOF_EXPR
              || expr.original_code == PAREN_SIZEOF_EXPR))
        {
          sizeof_arg[idx] = c_last_sizeof_arg;
          sizeof_arg_loc[idx] = c_last_sizeof_loc;
        }
    }
  if (orig_types)
    *p_orig_types = orig_types;
  c_omp_array_section_p = save_c_omp_array_section_p;
  return ret;
}
\f
/* Parse Objective-C-specific constructs.  */

/* Parse an objc-class-definition.

   objc-class-definition:
     @interface identifier objc-superclass[opt] objc-protocol-refs[opt]
       objc-class-instance-variables[opt] objc-methodprotolist @end
     @implementation identifier objc-superclass[opt]
       objc-class-instance-variables[opt]
     @interface identifier ( identifier ) objc-protocol-refs[opt]
       objc-methodprotolist @end
     @interface identifier ( ) objc-protocol-refs[opt]
       objc-methodprotolist @end
     @implementation identifier ( identifier )

   objc-superclass:
     : identifier

   "@interface identifier (" must start "@interface identifier (
   identifier ) ...": objc-methodprotolist in the first production may
   not start with a parenthesized identifier as a declarator of a data
   definition with no declaration specifiers if the objc-superclass,
   objc-protocol-refs and objc-class-instance-variables are omitted.  */

static void
c_parser_objc_class_definition (c_parser *parser, tree attributes)
{
  bool iface_p;
  tree id1;
  tree superclass;
  if (c_parser_next_token_is_keyword (parser, RID_AT_INTERFACE))
    iface_p = true;
  else if (c_parser_next_token_is_keyword (parser, RID_AT_IMPLEMENTATION))
    iface_p = false;
  else
    gcc_unreachable ();

  c_parser_consume_token (parser);
  if (c_parser_next_token_is_not (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected identifier");
      return;
    }
  id1 = c_parser_peek_token (parser)->value;
  location_t loc1 = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      /* We have a category or class extension.  */
      tree id2;
      tree proto = NULL_TREE;
      matching_parens parens;
      parens.consume_open (parser);
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          if (iface_p && c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
            {
              /* We have a class extension.  */
              id2 = NULL_TREE;
            }
          else
            {
              c_parser_error (parser, "expected identifier or %<)%>");
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
              return;
            }
        }
      else
        {
          id2 = c_parser_peek_token (parser)->value;
          c_parser_consume_token (parser);
        }
      parens.skip_until_found_close (parser);
      if (!iface_p)
        {
          objc_start_category_implementation (id1, id2);
          return;
        }
      if (c_parser_next_token_is (parser, CPP_LESS))
        proto = c_parser_objc_protocol_refs (parser);
      objc_start_category_interface (id1, id2, proto, attributes);
      c_parser_objc_methodprotolist (parser);
      c_parser_require_keyword (parser, RID_AT_END, "expected %<@end%>");
      objc_finish_interface ();
      return;
    }
  if (c_parser_next_token_is (parser, CPP_COLON))
    {
      c_parser_consume_token (parser);
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          return;
        }
      superclass = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);
    }
  else
    superclass = NULL_TREE;
  if (iface_p)
    {
      tree proto = NULL_TREE;
      if (c_parser_next_token_is (parser, CPP_LESS))
        proto = c_parser_objc_protocol_refs (parser);
      objc_start_class_interface (id1, loc1, superclass, proto, attributes);
    }
  else
    objc_start_class_implementation (id1, superclass);
  if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    c_parser_objc_class_instance_variables (parser);
  if (iface_p)
    {
      objc_continue_interface ();
      c_parser_objc_methodprotolist (parser);
      c_parser_require_keyword (parser, RID_AT_END, "expected %<@end%>");
      objc_finish_interface ();
    }
  else
    {
      objc_continue_implementation ();
      return;
    }
}

/* Parse objc-class-instance-variables.

   objc-class-instance-variables:
     { objc-instance-variable-decl-list[opt] }

   objc-instance-variable-decl-list:
     objc-visibility-spec
     objc-instance-variable-decl ;
     ;
     objc-instance-variable-decl-list objc-visibility-spec
     objc-instance-variable-decl-list objc-instance-variable-decl ;
     objc-instance-variable-decl-list ;

   objc-visibility-spec:
     @private
     @protected
     @public

   objc-instance-variable-decl:
     struct-declaration
*/

static void
c_parser_objc_class_instance_variables (c_parser *parser)
{
  gcc_assert (c_parser_next_token_is (parser, CPP_OPEN_BRACE));
  c_parser_consume_token (parser);
  while (c_parser_next_token_is_not (parser, CPP_EOF))
    {
      tree decls;
      /* Parse any stray semicolon.  */
      if (c_parser_next_token_is (parser, CPP_SEMICOLON))
        {
          pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
                   "extra semicolon");
          c_parser_consume_token (parser);
          continue;
        }
      /* Stop if at the end of the instance variables.  */
      if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
        {
          c_parser_consume_token (parser);
          break;
        }
      /* Parse any objc-visibility-spec.  */
      if (c_parser_next_token_is_keyword (parser, RID_AT_PRIVATE))
        {
          c_parser_consume_token (parser);
          objc_set_visibility (OBJC_IVAR_VIS_PRIVATE);
          continue;
        }
      else if (c_parser_next_token_is_keyword (parser, RID_AT_PROTECTED))
        {
          c_parser_consume_token (parser);
          objc_set_visibility (OBJC_IVAR_VIS_PROTECTED);
          continue;
        }
      else if (c_parser_next_token_is_keyword (parser, RID_AT_PUBLIC))
        {
          c_parser_consume_token (parser);
          objc_set_visibility (OBJC_IVAR_VIS_PUBLIC);
          continue;
        }
      else if (c_parser_next_token_is_keyword (parser, RID_AT_PACKAGE))
        {
          c_parser_consume_token (parser);
          objc_set_visibility (OBJC_IVAR_VIS_PACKAGE);
          continue;
        }
      else if (c_parser_next_token_is (parser, CPP_PRAGMA))
        {
          c_parser_pragma (parser, pragma_external, NULL);
          continue;
        }

      /* Parse some comma-separated declarations.  */
      decls = c_parser_struct_declaration (parser, NULL);
      if (decls == NULL)
        {
          /* There is a syntax error.  We want to skip the offending
             tokens up to the next ';' (included) or '}'
             (excluded).  */
          
          /* First, skip manually a ')' or ']'.  This is because they
             reduce the nesting level, so c_parser_skip_until_found()
             wouldn't be able to skip past them.  */
          c_token *token = c_parser_peek_token (parser);
          if (token->type == CPP_CLOSE_PAREN || token->type == CPP_CLOSE_SQUARE)
            c_parser_consume_token (parser);

          /* Then, do the standard skipping.  */
          c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);

          /* We hopefully recovered.  Start normal parsing again.  */
          parser->error = false;
          continue;
        }
      else
        {
          /* Comma-separated instance variables are chained together
             in reverse order; add them one by one.  */
          tree ivar = nreverse (decls);
          for (; ivar; ivar = DECL_CHAIN (ivar))
            objc_add_instance_variable (copy_node (ivar));
        }
      c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
    }
}

/* Parse an objc-class-declaration.

   objc-class-declaration:
     @class identifier-list ;
*/

static void
c_parser_objc_class_declaration (c_parser *parser)
{
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_CLASS));
  c_parser_consume_token (parser);
  /* Any identifiers, including those declared as type names, are OK
     here.  */
  while (true)
    {
      tree id;
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
          parser->error = false;
          return;
        }
      id = c_parser_peek_token (parser)->value;
      objc_declare_class (id);
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
}

/* Parse an objc-alias-declaration.

   objc-alias-declaration:
     @compatibility_alias identifier identifier ;
*/

static void
c_parser_objc_alias_declaration (c_parser *parser)
{
  tree id1, id2;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_ALIAS));
  c_parser_consume_token (parser);
  if (c_parser_next_token_is_not (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected identifier");
      c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
      return;
    }
  id1 = c_parser_peek_token (parser)->value;
  c_parser_consume_token (parser);
  if (c_parser_next_token_is_not (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected identifier");
      c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
      return;
    }
  id2 = c_parser_peek_token (parser)->value;
  c_parser_consume_token (parser);
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
  objc_declare_alias (id1, id2);
}

/* Parse an objc-protocol-definition.

   objc-protocol-definition:
     @protocol identifier objc-protocol-refs[opt] objc-methodprotolist @end
     @protocol identifier-list ;

   "@protocol identifier ;" should be resolved as "@protocol
   identifier-list ;": objc-methodprotolist may not start with a
   semicolon in the first alternative if objc-protocol-refs are
   omitted.  */

static void
c_parser_objc_protocol_definition (c_parser *parser, tree attributes)
{
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_PROTOCOL));

  c_parser_consume_token (parser);
  if (c_parser_next_token_is_not (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected identifier");
      return;
    }
  if (c_parser_peek_2nd_token (parser)->type == CPP_COMMA
      || c_parser_peek_2nd_token (parser)->type == CPP_SEMICOLON)
    {
      /* Any identifiers, including those declared as type names, are
         OK here.  */
      while (true)
        {
          tree id;
          if (c_parser_next_token_is_not (parser, CPP_NAME))
            {
              c_parser_error (parser, "expected identifier");
              break;
            }
          id = c_parser_peek_token (parser)->value;
          objc_declare_protocol (id, attributes);
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_COMMA))
            c_parser_consume_token (parser);
          else
            break;
        }
      c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
    }
  else
    {
      tree id = c_parser_peek_token (parser)->value;
      tree proto = NULL_TREE;
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_LESS))
        proto = c_parser_objc_protocol_refs (parser);
      parser->objc_pq_context = true;
      objc_start_protocol (id, proto, attributes);
      c_parser_objc_methodprotolist (parser);
      c_parser_require_keyword (parser, RID_AT_END, "expected %<@end%>");
      parser->objc_pq_context = false;
      objc_finish_interface ();
    }
}

/* Parse an objc-method-type.

   objc-method-type:
     +
     -

   Return true if it is a class method (+) and false if it is
   an instance method (-).
*/
static inline bool
c_parser_objc_method_type (c_parser *parser)
{
  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_PLUS:
      c_parser_consume_token (parser);
      return true;
    case CPP_MINUS:
      c_parser_consume_token (parser);
      return false;
    default:
      gcc_unreachable ();
    }
}

/* Parse an objc-method-definition.

   objc-method-definition:
     objc-method-type objc-method-decl ;[opt] compound-statement
*/

static void
c_parser_objc_method_definition (c_parser *parser)
{
  bool is_class_method = c_parser_objc_method_type (parser);
  tree decl, attributes = NULL_TREE, expr = NULL_TREE;
  parser->objc_pq_context = true;
  decl = c_parser_objc_method_decl (parser, is_class_method, &attributes,
                                    &expr);
  if (decl == error_mark_node)
    return;  /* Bail here. */

  if (c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      c_parser_consume_token (parser);
      pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
               "extra semicolon in method definition specified");
    }

  if (!c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    {
      c_parser_error (parser, "expected %<{%>");
      return;
    }

  parser->objc_pq_context = false;
  if (objc_start_method_definition (is_class_method, decl, attributes, expr))
    {
      add_stmt (c_parser_compound_statement (parser));
      objc_finish_method_definition (current_function_decl);
    }
  else
    {
      /* This code is executed when we find a method definition
         outside of an @implementation context (or invalid for other
         reasons).  Parse the method (to keep going) but do not emit
         any code.
      */
      c_parser_compound_statement (parser);
    }
}

/* Parse an objc-methodprotolist.

   objc-methodprotolist:
     empty
     objc-methodprotolist objc-methodproto
     objc-methodprotolist declaration
     objc-methodprotolist ;
     @optional
     @required

   The declaration is a data definition, which may be missing
   declaration specifiers under the same rules and diagnostics as
   other data definitions outside functions, and the stray semicolon
   is diagnosed the same way as a stray semicolon outside a
   function.  */

static void
c_parser_objc_methodprotolist (c_parser *parser)
{
  while (true)
    {
      /* The list is terminated by @end.  */
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_SEMICOLON:
          pedwarn (c_parser_peek_token (parser)->location, OPT_Wpedantic,
                   "ISO C does not allow extra %<;%> outside of a function");
          c_parser_consume_token (parser);
          break;
        case CPP_PLUS:
        case CPP_MINUS:
          c_parser_objc_methodproto (parser);
          break;
        case CPP_PRAGMA:
          c_parser_pragma (parser, pragma_external, NULL);
          break;
        case CPP_EOF:
          return;
        default:
          if (c_parser_next_token_is_keyword (parser, RID_AT_END))
            return;
          else if (c_parser_next_token_is_keyword (parser, RID_AT_PROPERTY))
            c_parser_objc_at_property_declaration (parser);
          else if (c_parser_next_token_is_keyword (parser, RID_AT_OPTIONAL))
            {
              objc_set_method_opt (true);
              c_parser_consume_token (parser);
            }
          else if (c_parser_next_token_is_keyword (parser, RID_AT_REQUIRED))
            {
              objc_set_method_opt (false);
              c_parser_consume_token (parser);
            }
          else
            c_parser_declaration_or_fndef (parser, false, false, true,
                                           false, true);
          break;
        }
    }
}

/* Parse an objc-methodproto.

   objc-methodproto:
     objc-method-type objc-method-decl ;
*/

static void
c_parser_objc_methodproto (c_parser *parser)
{
  bool is_class_method = c_parser_objc_method_type (parser);
  tree decl, attributes = NULL_TREE;

  /* Remember protocol qualifiers in prototypes.  */
  parser->objc_pq_context = true;
  decl = c_parser_objc_method_decl (parser, is_class_method, &attributes,
                                    NULL);
  /* Forget protocol qualifiers now.  */
  parser->objc_pq_context = false;

  /* Do not allow the presence of attributes to hide an erroneous 
     method implementation in the interface section.  */
  if (!c_parser_next_token_is (parser, CPP_SEMICOLON))
    {
      c_parser_error (parser, "expected %<;%>");
      return;
    }
  
  if (decl != error_mark_node)
    objc_add_method_declaration (is_class_method, decl, attributes);

  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
}

/* If we are at a position that method attributes may be present, check that 
   there are not any parsed already (a syntax error) and then collect any 
   specified at the current location.  Finally, if new attributes were present,
   check that the next token is legal ( ';' for decls and '{' for defs).  */
   
static bool 
c_parser_objc_maybe_method_attributes (c_parser* parser, tree* attributes)
{
  bool bad = false;
  if (*attributes)
    {
      c_parser_error (parser, 
                    "method attributes must be specified at the end only");
      *attributes = NULL_TREE;
      bad = true;
    }

  if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
    *attributes = c_parser_gnu_attributes (parser);

  /* If there were no attributes here, just report any earlier error.  */
  if (*attributes == NULL_TREE || bad)
    return bad;

  /* If the attributes are followed by a ; or {, then just report any earlier
     error.  */
  if (c_parser_next_token_is (parser, CPP_SEMICOLON)
      || c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    return bad;

  /* We've got attributes, but not at the end.  */
  c_parser_error (parser, 
                  "expected %<;%> or %<{%> after method attribute definition");
  return true;
}

/* Parse an objc-method-decl.

   objc-method-decl:
     ( objc-type-name ) objc-selector
     objc-selector
     ( objc-type-name ) objc-keyword-selector objc-optparmlist
     objc-keyword-selector objc-optparmlist
     gnu-attributes

   objc-keyword-selector:
     objc-keyword-decl
     objc-keyword-selector objc-keyword-decl

   objc-keyword-decl:
     objc-selector : ( objc-type-name ) identifier
     objc-selector : identifier
     : ( objc-type-name ) identifier
     : identifier

   objc-optparmlist:
     objc-optparms objc-optellipsis

   objc-optparms:
     empty
     objc-opt-parms , parameter-declaration

   objc-optellipsis:
     empty
     , ...
*/

static tree
c_parser_objc_method_decl (c_parser *parser, bool is_class_method,
                           tree *attributes, tree *expr)
{
  tree type = NULL_TREE;
  tree sel;
  tree parms = NULL_TREE;
  bool ellipsis = false;
  bool attr_err = false;

  *attributes = NULL_TREE;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      matching_parens parens;
      parens.consume_open (parser);
      type = c_parser_objc_type_name (parser);
      parens.skip_until_found_close (parser);
    }
  sel = c_parser_objc_selector (parser);
  /* If there is no selector, or a colon follows, we have an
     objc-keyword-selector.  If there is a selector, and a colon does
     not follow, that selector ends the objc-method-decl.  */
  if (!sel || c_parser_next_token_is (parser, CPP_COLON))
    {
      tree tsel = sel;
      tree list = NULL_TREE;
      while (true)
        {
          tree atype = NULL_TREE, id, keyworddecl;
          tree param_attr = NULL_TREE;
          if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
            break;
          if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
            {
              c_parser_consume_token (parser);
              atype = c_parser_objc_type_name (parser);
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                         "expected %<)%>");
            }
          /* New ObjC allows attributes on method parameters.  */
          if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
            param_attr = c_parser_gnu_attributes (parser);
          if (c_parser_next_token_is_not (parser, CPP_NAME))
            {
              c_parser_error (parser, "expected identifier");
              return error_mark_node;
            }
          id = c_parser_peek_token (parser)->value;
          c_parser_consume_token (parser);
          keyworddecl = objc_build_keyword_decl (tsel, atype, id, param_attr);
          list = chainon (list, keyworddecl);
          tsel = c_parser_objc_selector (parser);
          if (!tsel && c_parser_next_token_is_not (parser, CPP_COLON))
            break;
        }

      attr_err |= c_parser_objc_maybe_method_attributes (parser, attributes) ;

      /* Parse the optional parameter list.  Optional Objective-C
         method parameters follow the C syntax, and may include '...'
         to denote a variable number of arguments.  */
      parms = make_node (TREE_LIST);
      while (c_parser_next_token_is (parser, CPP_COMMA))
        {
          struct c_parm *parm;
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_ELLIPSIS))
            {
              ellipsis = true;
              c_parser_consume_token (parser);
              attr_err |= c_parser_objc_maybe_method_attributes 
                                                (parser, attributes) ;
              break;
            }
          parm = c_parser_parameter_declaration (parser, NULL_TREE, false);
          if (parm == NULL)
            break;
          parms = chainon (parms,
                           build_tree_list (NULL_TREE, grokparm (parm, expr)));
        }
      sel = list;
    }
  else
    attr_err |= c_parser_objc_maybe_method_attributes (parser, attributes) ;

  if (sel == NULL)
    {
      c_parser_error (parser, "objective-c method declaration is expected");
      return error_mark_node;
    }

  if (attr_err)
    return error_mark_node;

  return objc_build_method_signature (is_class_method, type, sel, parms, ellipsis);
}

/* Parse an objc-type-name.

   objc-type-name:
     objc-type-qualifiers[opt] type-name
     objc-type-qualifiers[opt]

   objc-type-qualifiers:
     objc-type-qualifier
     objc-type-qualifiers objc-type-qualifier

   objc-type-qualifier: one of
     in out inout bycopy byref oneway
*/

static tree
c_parser_objc_type_name (c_parser *parser)
{
  tree quals = NULL_TREE;
  struct c_type_name *type_name = NULL;
  tree type = NULL_TREE;
  while (true)
    {
      c_token *token = c_parser_peek_token (parser);
      if (token->type == CPP_KEYWORD
          && (token->keyword == RID_IN
              || token->keyword == RID_OUT
              || token->keyword == RID_INOUT
              || token->keyword == RID_BYCOPY
              || token->keyword == RID_BYREF
              || token->keyword == RID_ONEWAY))
        {
          quals = chainon (build_tree_list (NULL_TREE, token->value), quals);
          c_parser_consume_token (parser);
        }
      else
        break;
    }
  if (c_parser_next_tokens_start_typename (parser, cla_prefer_type))
    type_name = c_parser_type_name (parser);
  if (type_name)
    type = groktypename (type_name, NULL, NULL);

  /* If the type is unknown, and error has already been produced and
     we need to recover from the error.  In that case, use NULL_TREE
     for the type, as if no type had been specified; this will use the
     default type ('id') which is good for error recovery.  */
  if (type == error_mark_node)
    type = NULL_TREE;

  return build_tree_list (quals, type);
}

/* Parse objc-protocol-refs.

   objc-protocol-refs:
     < identifier-list >
*/

static tree
c_parser_objc_protocol_refs (c_parser *parser)
{
  tree list = NULL_TREE;
  gcc_assert (c_parser_next_token_is (parser, CPP_LESS));
  c_parser_consume_token (parser);
  /* Any identifiers, including those declared as type names, are OK
     here.  */
  while (true)
    {
      tree id;
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          break;
        }
      id = c_parser_peek_token (parser)->value;
      list = chainon (list, build_tree_list (NULL_TREE, id));
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  c_parser_require (parser, CPP_GREATER, "expected %<>%>");
  return list;
}

/* Parse an objc-try-catch-finally-statement.

   objc-try-catch-finally-statement:
     @try compound-statement objc-catch-list[opt]
     @try compound-statement objc-catch-list[opt] @finally compound-statement

   objc-catch-list:
     @catch ( objc-catch-parameter-declaration ) compound-statement
     objc-catch-list @catch ( objc-catch-parameter-declaration ) compound-statement

   objc-catch-parameter-declaration:
     parameter-declaration
     '...'

   where '...' is to be interpreted literally, that is, it means CPP_ELLIPSIS.

   PS: This function is identical to cp_parser_objc_try_catch_finally_statement
   for C++.  Keep them in sync.  */   

static void
c_parser_objc_try_catch_finally_statement (c_parser *parser)
{
  location_t location;
  tree stmt;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_TRY));
  c_parser_consume_token (parser);
  location = c_parser_peek_token (parser)->location;
  objc_maybe_warn_exceptions (location);
  stmt = c_parser_compound_statement (parser);
  objc_begin_try_stmt (location, stmt);

  while (c_parser_next_token_is_keyword (parser, RID_AT_CATCH))
    {
      struct c_parm *parm;
      tree parameter_declaration = error_mark_node;
      bool seen_open_paren = false;

      c_parser_consume_token (parser);
      matching_parens parens;
      if (!parens.require_open (parser))
        seen_open_paren = true;
      if (c_parser_next_token_is (parser, CPP_ELLIPSIS))
        {
          /* We have "@catch (...)" (where the '...' are literally
             what is in the code).  Skip the '...'.
             parameter_declaration is set to NULL_TREE, and
             objc_being_catch_clauses() knows that that means
             '...'.  */
          c_parser_consume_token (parser);
          parameter_declaration = NULL_TREE;
        }
      else
        {
          /* We have "@catch (NSException *exception)" or something
             like that.  Parse the parameter declaration.  */
          parm = c_parser_parameter_declaration (parser, NULL_TREE, false);
          if (parm == NULL)
            parameter_declaration = error_mark_node;
          else
            parameter_declaration = grokparm (parm, NULL);
        }
      if (seen_open_paren)
        parens.require_close (parser);
      else
        {
          /* If there was no open parenthesis, we are recovering from
             an error, and we are trying to figure out what mistake
             the user has made.  */

          /* If there is an immediate closing parenthesis, the user
             probably forgot the opening one (ie, they typed "@catch
             NSException *e)".  Parse the closing parenthesis and keep
             going.  */
          if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
            c_parser_consume_token (parser);
          
          /* If these is no immediate closing parenthesis, the user
             probably doesn't know that parenthesis are required at
             all (ie, they typed "@catch NSException *e").  So, just
             forget about the closing parenthesis and keep going.  */
        }
      objc_begin_catch_clause (parameter_declaration);
      if (c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
        c_parser_compound_statement_nostart (parser);
      objc_finish_catch_clause ();
    }
  if (c_parser_next_token_is_keyword (parser, RID_AT_FINALLY))
    {
      c_parser_consume_token (parser);
      location = c_parser_peek_token (parser)->location;
      stmt = c_parser_compound_statement (parser);
      objc_build_finally_clause (location, stmt);
    }
  objc_finish_try_stmt ();
}

/* Parse an objc-synchronized-statement.

   objc-synchronized-statement:
     @synchronized ( expression ) compound-statement
*/

static void
c_parser_objc_synchronized_statement (c_parser *parser)
{
  location_t loc;
  tree expr, stmt;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_SYNCHRONIZED));
  c_parser_consume_token (parser);
  loc = c_parser_peek_token (parser)->location;
  objc_maybe_warn_exceptions (loc);
  matching_parens parens;
  if (parens.require_open (parser))
    {
      struct c_expr ce = c_parser_expression (parser);
      ce = convert_lvalue_to_rvalue (loc, ce, false, false);
      expr = ce.value;
      expr = c_fully_fold (expr, false, NULL);
      parens.skip_until_found_close (parser);
    }
  else
    expr = error_mark_node;
  stmt = c_parser_compound_statement (parser);
  objc_build_synchronized (loc, expr, stmt);
}

/* Parse an objc-selector; return NULL_TREE without an error if the
   next token is not an objc-selector.

   objc-selector:
     identifier
     one of
       enum struct union if else while do for switch case default
       break continue return goto asm sizeof typeof typeof_unqual __alignof
       unsigned long const short volatile signed restrict _Complex
       in out inout bycopy byref oneway int char float double void _Bool
       _Atomic

   ??? Why this selection of keywords but not, for example, storage
   class specifiers?  */

static tree
c_parser_objc_selector (c_parser *parser)
{
  c_token *token = c_parser_peek_token (parser);
  tree value = token->value;
  if (token->type == CPP_NAME)
    {
      c_parser_consume_token (parser);
      return value;
    }
  if (token->type != CPP_KEYWORD)
    return NULL_TREE;
  switch (token->keyword)
    {
    case RID_ENUM:
    case RID_STRUCT:
    case RID_UNION:
    case RID_IF:
    case RID_ELSE:
    case RID_WHILE:
    case RID_DO:
    case RID_FOR:
    case RID_SWITCH:
    case RID_CASE:
    case RID_DEFAULT:
    case RID_BREAK:
    case RID_CONTINUE:
    case RID_RETURN:
    case RID_GOTO:
    case RID_ASM:
    case RID_SIZEOF:
    case RID_TYPEOF:
    case RID_TYPEOF_UNQUAL:
    case RID_ALIGNOF:
    case RID_UNSIGNED:
    case RID_LONG:
    case RID_CONST:
    case RID_SHORT:
    case RID_VOLATILE:
    case RID_SIGNED:
    case RID_RESTRICT:
    case RID_COMPLEX:
    case RID_IN:
    case RID_OUT:
    case RID_INOUT:
    case RID_BYCOPY:
    case RID_BYREF:
    case RID_ONEWAY:
    case RID_INT:
    case RID_CHAR:
    case RID_FLOAT:
    case RID_DOUBLE:
    CASE_RID_FLOATN_NX:
    case RID_VOID:
    case RID_BOOL:
    case RID_ATOMIC:
    case RID_AUTO_TYPE:
    case RID_INT_N_0:
    case RID_INT_N_1:
    case RID_INT_N_2:
    case RID_INT_N_3:
      c_parser_consume_token (parser);
      return value;
    default:
      return NULL_TREE;
    }
}

/* Parse an objc-selector-arg.

   objc-selector-arg:
     objc-selector
     objc-keywordname-list

   objc-keywordname-list:
     objc-keywordname
     objc-keywordname-list objc-keywordname

   objc-keywordname:
     objc-selector :
     :
*/

static tree
c_parser_objc_selector_arg (c_parser *parser)
{
  tree sel = c_parser_objc_selector (parser);
  tree list = NULL_TREE;
  if (sel
      && c_parser_next_token_is_not (parser, CPP_COLON)
      && c_parser_next_token_is_not (parser, CPP_SCOPE))
    return sel;
  while (true)
    {
      if (c_parser_next_token_is (parser, CPP_SCOPE))
        {
          c_parser_consume_token (parser);
          list = chainon (list, build_tree_list (sel, NULL_TREE));
          list = chainon (list, build_tree_list (NULL_TREE, NULL_TREE));
        }
      else
        {
          if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
            return list;
          list = chainon (list, build_tree_list (sel, NULL_TREE));
        }
      sel = c_parser_objc_selector (parser);
      if (!sel
          && c_parser_next_token_is_not (parser, CPP_COLON)
          && c_parser_next_token_is_not (parser, CPP_SCOPE))
        break;
    }
  return list;
}

/* Parse an objc-receiver.

   objc-receiver:
     expression
     class-name
     type-name
*/

static tree
c_parser_objc_receiver (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;

  if (c_parser_peek_token (parser)->type == CPP_NAME
      && (c_parser_peek_token (parser)->id_kind == C_ID_TYPENAME
          || c_parser_peek_token (parser)->id_kind == C_ID_CLASSNAME))
    {
      tree id = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);
      return objc_get_class_reference (id);
    }
  struct c_expr ce = c_parser_expression (parser);
  ce = convert_lvalue_to_rvalue (loc, ce, false, false);
  return c_fully_fold (ce.value, false, NULL);
}

/* Parse objc-message-args.

   objc-message-args:
     objc-selector
     objc-keywordarg-list

   objc-keywordarg-list:
     objc-keywordarg
     objc-keywordarg-list objc-keywordarg

   objc-keywordarg:
     objc-selector : objc-keywordexpr
     : objc-keywordexpr
*/

static tree
c_parser_objc_message_args (c_parser *parser)
{
  tree sel = c_parser_objc_selector (parser);
  tree list = NULL_TREE;
  if (sel && c_parser_next_token_is_not (parser, CPP_COLON))
    return sel;
  while (true)
    {
      tree keywordexpr;
      if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        return error_mark_node;
      keywordexpr = c_parser_objc_keywordexpr (parser);
      list = chainon (list, build_tree_list (sel, keywordexpr));
      sel = c_parser_objc_selector (parser);
      if (!sel && c_parser_next_token_is_not (parser, CPP_COLON))
        break;
    }
  return list;
}

/* Parse an objc-keywordexpr.

   objc-keywordexpr:
     nonempty-expr-list
*/

static tree
c_parser_objc_keywordexpr (c_parser *parser)
{
  tree ret;
  vec<tree, va_gc> *expr_list = c_parser_expr_list (parser, true, true,
                                                NULL, NULL, NULL, NULL);
  if (vec_safe_length (expr_list) == 1)
    {
      /* Just return the expression, remove a level of
         indirection.  */
      ret = (*expr_list)[0];
    }
  else
    {
      /* We have a comma expression, we will collapse later.  */
      ret = build_tree_list_vec (expr_list);
    }
  release_tree_vector (expr_list);
  return ret;
}

/* A check, needed in several places, that ObjC interface, implementation or
   method definitions are not prefixed by incorrect items.  */
static bool
c_parser_objc_diagnose_bad_element_prefix (c_parser *parser, 
                                           struct c_declspecs *specs)
{
  if (!specs->declspecs_seen_p || specs->non_sc_seen_p
      || specs->typespec_kind != ctsk_none)
    {
      c_parser_error (parser, 
                      "no type or storage class may be specified here,");
      c_parser_skip_to_end_of_block_or_statement (parser);
      return true;
    }
  return false;
}

/* Parse an Objective-C @property declaration.  The syntax is:

   objc-property-declaration:
     '@property' objc-property-attributes[opt] struct-declaration ;

   objc-property-attributes:
    '(' objc-property-attribute-list ')'

   objc-property-attribute-list:
     objc-property-attribute
     objc-property-attribute-list, objc-property-attribute

   objc-property-attribute
     'getter' = identifier
     'setter' = identifier
     'readonly'
     'readwrite'
     'assign'
     'retain'
     'copy'
     'nonatomic'

  For example:
    @property NSString *name;
    @property (readonly) id object;
    @property (retain, nonatomic, getter=getTheName) id name;
    @property int a, b, c;

  PS: This function is identical to cp_parser_objc_at_propery_declaration
  for C++.  Keep them in sync.  */
static void
c_parser_objc_at_property_declaration (c_parser *parser)
{
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_PROPERTY));
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_token (parser);  /* Eat '@property'.  */

  /* Parse the optional attribute list.

     A list of parsed, but not verified, attributes.  */
  vec<property_attribute_info *> prop_attr_list = vNULL;

  bool syntax_error = false;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      matching_parens parens;

      location_t attr_start = c_parser_peek_token (parser)->location;
      /* Eat the '(' */
      parens.consume_open (parser);

      /* Property attribute keywords are valid now.  */
      parser->objc_property_attr_context = true;

      /* Allow @property (), with a warning.  */
      location_t attr_end = c_parser_peek_token (parser)->location;

      if (c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        {
          location_t attr_comb = make_location (attr_end, attr_start, attr_end);
          warning_at (attr_comb, OPT_Wattributes,
                      "empty property attribute list");
        }
      else
        while (true)
          {
            c_token *token = c_parser_peek_token (parser);
            attr_start = token->location;
            attr_end = get_finish (token->location);
            location_t attr_comb = make_location (attr_start, attr_start,
                                                  attr_end);

            if (token->type == CPP_CLOSE_PAREN || token->type == CPP_COMMA)
              {
                warning_at (attr_comb, OPT_Wattributes,
                            "missing property attribute");
                if (token->type == CPP_CLOSE_PAREN)
                  break;
                c_parser_consume_token (parser);
                continue;
              }

            tree attr_name = NULL_TREE;
            enum rid keyword = RID_MAX; /* Not a valid property attribute.  */
            bool add_at = false;
            if (token->type == CPP_KEYWORD)
              {
                keyword = token->keyword;
                if (OBJC_IS_AT_KEYWORD (keyword))
                  {
                    /* For '@' keywords the token value has the keyword,
                       prepend the '@' for diagnostics.  */
                    attr_name = token->value;
                    add_at = true;
                  }
                else
                  attr_name = ridpointers[(int)keyword];
              }
            else if (token->type == CPP_NAME)
              attr_name = token->value;
            c_parser_consume_token (parser);

            enum objc_property_attribute_kind prop_kind
              = objc_prop_attr_kind_for_rid (keyword);
            property_attribute_info *prop
              = new property_attribute_info (attr_name, attr_comb, prop_kind);
            prop_attr_list.safe_push (prop);

            tree meth_name;
            switch (prop->prop_kind)
              {
              default: break;
              case OBJC_PROPERTY_ATTR_UNKNOWN:
                if (attr_name)
                  error_at (attr_comb, "unknown property attribute %<%s%s%>",
                            add_at ? "@" : "", IDENTIFIER_POINTER (attr_name));
                else
                  error_at (attr_comb, "unknown property attribute");
                prop->parse_error = syntax_error = true;
                break;

              case OBJC_PROPERTY_ATTR_GETTER:
              case OBJC_PROPERTY_ATTR_SETTER:
                if (c_parser_next_token_is_not (parser, CPP_EQ))
                  {
                    attr_comb = make_location (attr_end, attr_start, attr_end);
                    error_at (attr_comb, "expected %<=%> after Objective-C %qE",
                              attr_name);
                    prop->parse_error = syntax_error = true;
                    break;
                  }
                token = c_parser_peek_token (parser);
                attr_end = token->location;
                c_parser_consume_token (parser); /* eat the = */
                if (c_parser_next_token_is_not (parser, CPP_NAME))
                  {
                    attr_comb = make_location (attr_end, attr_start, attr_end);
                    error_at (attr_comb, "expected %qE selector name",
                              attr_name);
                    prop->parse_error = syntax_error = true;
                    break;
                  }
                /* Get the end of the method name, and consume the name.  */
                token = c_parser_peek_token (parser);
                attr_end = get_finish (token->location);
                meth_name = token->value;
                c_parser_consume_token (parser);
                if (prop->prop_kind == OBJC_PROPERTY_ATTR_SETTER)
                  {
                    if (c_parser_next_token_is_not (parser, CPP_COLON))
                      {
                        attr_comb = make_location (attr_end, attr_start,
                                                   attr_end);
                        error_at (attr_comb, "setter method names must"
                                  " terminate with %<:%>");
                        prop->parse_error = syntax_error = true;
                      }
                    else
                      {
                        attr_end = get_finish (c_parser_peek_token
                                               (parser)->location);
                        c_parser_consume_token (parser);
                      }
                    attr_comb = make_location (attr_start, attr_start,
                                               attr_end);
                  }
                else
                  attr_comb = make_location (attr_start, attr_start,
                                               attr_end);
                prop->ident = meth_name;
                /* Updated location including all that was successfully
                   parsed.  */
                prop->prop_loc = attr_comb;
                break;
            }

          /* If we see a comma here, then keep going - even if we already
             saw a syntax error.  For simple mistakes e.g. (asign, getter=x)
             this makes a more useful output and avoid spurious warnings about
             missing attributes that are, in fact, specified after the one with
             the syntax error.  */
          if (c_parser_next_token_is (parser, CPP_COMMA))
            c_parser_consume_token (parser);
          else
            break;
        }
      parser->objc_property_attr_context = false;

      if (syntax_error && c_parser_next_token_is_not (parser, CPP_CLOSE_PAREN))
        /* We don't really want to chew the whole of the file looking for a
           matching closing parenthesis, so we will try to read the decl and
           let the error handling for that close out the statement.  */
        ;
      else
        syntax_error = false, parens.skip_until_found_close (parser);
    }

  /* 'properties' is the list of properties that we read.  Usually a
     single one, but maybe more (eg, in "@property int a, b, c;" there
     are three).  */
  tree properties = c_parser_struct_declaration (parser, NULL);

  if (properties == error_mark_node)
    c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
  else
    {
      if (properties == NULL_TREE)
        c_parser_error (parser, "expected identifier");
      else
        {
          /* Comma-separated properties are chained together in reverse order;
             add them one by one.  */
          properties = nreverse (properties);
          for (; properties; properties = TREE_CHAIN (properties))
            objc_add_property_declaration (loc, copy_node (properties),
                                            prop_attr_list);
        }
      c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
    }

  while (!prop_attr_list.is_empty())
    delete prop_attr_list.pop ();
  prop_attr_list.release ();
  parser->error = false;
}

/* Parse an Objective-C @synthesize declaration.  The syntax is:

   objc-synthesize-declaration:
     @synthesize objc-synthesize-identifier-list ;

   objc-synthesize-identifier-list:
     objc-synthesize-identifier
     objc-synthesize-identifier-list, objc-synthesize-identifier

   objc-synthesize-identifier
     identifier
     identifier = identifier

  For example:
    @synthesize MyProperty;
    @synthesize OneProperty, AnotherProperty=MyIvar, YetAnotherProperty;

  PS: This function is identical to cp_parser_objc_at_synthesize_declaration
  for C++.  Keep them in sync.
*/
static void
c_parser_objc_at_synthesize_declaration (c_parser *parser)
{
  tree list = NULL_TREE;
  location_t loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_SYNTHESIZE));
  loc = c_parser_peek_token (parser)->location;

  c_parser_consume_token (parser);
  while (true)
    {
      tree property, ivar;
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
          /* Once we find the semicolon, we can resume normal parsing.
             We have to reset parser->error manually because
             c_parser_skip_until_found() won't reset it for us if the
             next token is precisely a semicolon.  */
          parser->error = false;
          return;
        }
      property = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_EQ))
        {
          c_parser_consume_token (parser);
          if (c_parser_next_token_is_not (parser, CPP_NAME))
            {
              c_parser_error (parser, "expected identifier");
              c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
              parser->error = false;
              return;
            }
          ivar = c_parser_peek_token (parser)->value;
          c_parser_consume_token (parser);
        }
      else
        ivar = NULL_TREE;
      list = chainon (list, build_tree_list (ivar, property));
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
  objc_add_synthesize_declaration (loc, list);
}

/* Parse an Objective-C @dynamic declaration.  The syntax is:

   objc-dynamic-declaration:
     @dynamic identifier-list ;

   For example:
     @dynamic MyProperty;
     @dynamic MyProperty, AnotherProperty;

  PS: This function is identical to cp_parser_objc_at_dynamic_declaration
  for C++.  Keep them in sync.
*/
static void
c_parser_objc_at_dynamic_declaration (c_parser *parser)
{
  tree list = NULL_TREE;
  location_t loc;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_AT_DYNAMIC));
  loc = c_parser_peek_token (parser)->location;

  c_parser_consume_token (parser);
  while (true)
    {
      tree property;
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          c_parser_skip_until_found (parser, CPP_SEMICOLON, NULL);
          parser->error = false;
          return;
        }
      property = c_parser_peek_token (parser)->value;
      list = chainon (list, build_tree_list (NULL_TREE, property));
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
  objc_add_dynamic_declaration (loc, list);
}

\f
/* Parse a pragma GCC ivdep.  */

static bool
c_parse_pragma_ivdep (c_parser *parser)
{
  c_parser_consume_pragma (parser);
  c_parser_skip_to_pragma_eol (parser);
  return true;
}

/* Parse a pragma GCC novector.  */

static bool
c_parse_pragma_novector (c_parser *parser)
{
  c_parser_consume_pragma (parser);
  c_parser_skip_to_pragma_eol (parser);
  return true;
}

/* Parse a pragma GCC unroll.  */

static unsigned short
c_parser_pragma_unroll (c_parser *parser)
{
  unsigned short unroll;
  c_parser_consume_pragma (parser);
  location_t location = c_parser_peek_token (parser)->location;
  tree expr = c_parser_expr_no_commas (parser, NULL).value;
  mark_exp_read (expr);
  expr = c_fully_fold (expr, false, NULL);
  HOST_WIDE_INT lunroll = 0;
  if (!INTEGRAL_TYPE_P (TREE_TYPE (expr))
      || TREE_CODE (expr) != INTEGER_CST
      || (lunroll = tree_to_shwi (expr)) < 0
      || lunroll >= USHRT_MAX)
    {
      error_at (location, "%<#pragma GCC unroll%> requires an"
                " assignment-expression that evaluates to a non-negative"
                " integral constant less than %u", USHRT_MAX);
      unroll = 0;
    }
  else
    {
      unroll = (unsigned short)lunroll;
      if (unroll == 0)
        unroll = 1;
    }

  c_parser_skip_to_pragma_eol (parser);
  return unroll;
}

/* Handle pragmas.  Some OpenMP pragmas are associated with, and therefore
   should be considered, statements.  ALLOW_STMT is true if we're within
   the context of a function and such pragmas are to be allowed.  Returns
   true if we actually parsed such a pragma.  */

static bool
c_parser_pragma (c_parser *parser, enum pragma_context context, bool *if_p)
{
  unsigned int id;
  const char *construct = NULL;

  input_location = c_parser_peek_token (parser)->location;
  id = c_parser_peek_token (parser)->pragma_kind;
  gcc_assert (id != PRAGMA_NONE);
  if (parser->omp_for_parse_state
      && parser->omp_for_parse_state->in_intervening_code
      && id >= PRAGMA_OMP__START_
      && id <= PRAGMA_OMP__LAST_)
    {
      error_at (input_location,
                "intervening code must not contain OpenMP directives");
      parser->omp_for_parse_state->fail = true;
      c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
      return false;
    }

  switch (id)
    {
    case PRAGMA_OACC_DECLARE:
      c_parser_oacc_declare (parser);
      return false;

    case PRAGMA_OACC_ENTER_DATA:
      if (context != pragma_compound)
        {
          construct = "acc enter data";
        in_compound:
          if (context == pragma_stmt)
            {
              error_at (c_parser_peek_token (parser)->location,
                        "%<#pragma %s%> may only be used in compound "
                        "statements", construct);
              c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
              return true;
            }
          goto bad_stmt;
        }
      c_parser_oacc_enter_exit_data (parser, true);
      return false;

    case PRAGMA_OACC_EXIT_DATA:
      if (context != pragma_compound)
        {
          construct = "acc exit data";
          goto in_compound;
        }
      c_parser_oacc_enter_exit_data (parser, false);
      return false;

    case PRAGMA_OACC_ROUTINE:
      if (context != pragma_external)
        {
          error_at (c_parser_peek_token (parser)->location,
                    "%<#pragma acc routine%> must be at file scope");
          c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
          return false;
        }
      c_parser_oacc_routine (parser, context);
      return false;

    case PRAGMA_OACC_UPDATE:
      if (context != pragma_compound)
        {
          construct = "acc update";
          goto in_compound;
        }
      c_parser_oacc_update (parser);
      return false;

    case PRAGMA_OMP_BARRIER:
      if (context != pragma_compound)
        {
          construct = "omp barrier";
          goto in_compound;
        }
      c_parser_omp_barrier (parser);
      return false;

    case PRAGMA_OMP_DEPOBJ:
      if (context != pragma_compound)
        {
          construct = "omp depobj";
          goto in_compound;
        }
      c_parser_omp_depobj (parser);
      return false;

    case PRAGMA_OMP_FLUSH:
      if (context != pragma_compound)
        {
          construct = "omp flush";
          goto in_compound;
        }
      c_parser_omp_flush (parser);
      return false;

    case PRAGMA_OMP_TASKWAIT:
      if (context != pragma_compound)
        {
          construct = "omp taskwait";
          goto in_compound;
        }
      c_parser_omp_taskwait (parser);
      return false;

    case PRAGMA_OMP_TASKYIELD:
      if (context != pragma_compound)
        {
          construct = "omp taskyield";
          goto in_compound;
        }
      c_parser_omp_taskyield (parser);
      return false;

    case PRAGMA_OMP_CANCEL:
      if (context != pragma_compound)
        {
          construct = "omp cancel";
          goto in_compound;
        }
      c_parser_omp_cancel (parser);
      return false;

    case PRAGMA_OMP_CANCELLATION_POINT:
      return c_parser_omp_cancellation_point (parser, context);

    case PRAGMA_OMP_THREADPRIVATE:
      c_parser_omp_threadprivate (parser);
      return false;

    case PRAGMA_OMP_TARGET:
      return c_parser_omp_target (parser, context, if_p);

    case PRAGMA_OMP_BEGIN:
      c_parser_omp_begin (parser);
      return false;

    case PRAGMA_OMP_END:
      c_parser_omp_end (parser);
      return false;

    case PRAGMA_OMP_SCAN:
      error_at (c_parser_peek_token (parser)->location,
                "%<#pragma omp scan%> may only be used in "
                "a loop construct with %<inscan%> %<reduction%> clause");
      c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
      return false;

    case PRAGMA_OMP_SECTION:
      error_at (c_parser_peek_token (parser)->location,
                "%<#pragma omp section%> may only be used in "
                "%<#pragma omp sections%> construct");
      c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
      return false;

    case PRAGMA_OMP_DECLARE:
      return c_parser_omp_declare (parser, context);

    case PRAGMA_OMP_REQUIRES:
      if (context != pragma_external)
        {
          error_at (c_parser_peek_token (parser)->location,
                    "%<#pragma %s%> may only be used at file scope",
                    "omp requires");
          c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
          return false;
        }
      c_parser_omp_requires (parser);
      return false;

    case PRAGMA_OMP_ALLOCATE:
      c_parser_omp_allocate (parser);
      return false;

    case PRAGMA_OMP_ASSUMES:
      if (context != pragma_external)
        {
          error_at (c_parser_peek_token (parser)->location,
                    "%<#pragma %s%> may only be used at file scope",
                    "omp assumes");
          c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
          return false;
        }
      c_parser_omp_assumes (parser);
      return false;

    case PRAGMA_OMP_NOTHING:
      c_parser_omp_nothing (parser);
      return false;

    case PRAGMA_OMP_ERROR:
      return c_parser_omp_error (parser, context);

    case PRAGMA_OMP_ORDERED:
      return c_parser_omp_ordered (parser, context, if_p);

    case PRAGMA_NOVECTOR:
    case PRAGMA_UNROLL:
    case PRAGMA_IVDEP:
      {
        bool novector = false;
        unsigned short unroll = 0;
        bool ivdep = false;

        switch (id)
          {
          case PRAGMA_NOVECTOR:
            novector = c_parse_pragma_novector (parser);
            break;
          case PRAGMA_UNROLL:
            unroll = c_parser_pragma_unroll (parser);
            break;
          case PRAGMA_IVDEP:
            ivdep = c_parse_pragma_ivdep (parser);
            break;
          default:
            gcc_unreachable ();
          }

        c_token *tok = c_parser_peek_token (parser);
        bool has_more = tok->type == CPP_PRAGMA;
        while (has_more)
          {
            switch (tok->pragma_kind)
              {
              case PRAGMA_IVDEP:
                ivdep = c_parse_pragma_ivdep (parser);
                break;
              case PRAGMA_UNROLL:
                unroll = c_parser_pragma_unroll (parser);
                break;
              case PRAGMA_NOVECTOR:
                novector = c_parse_pragma_novector (parser);
                break;
              default:
                has_more = false;
                break;
              }
            tok = c_parser_peek_token (parser);
            has_more = has_more && tok->type == CPP_PRAGMA;
          }
        if (!c_parser_next_token_is_keyword (parser, RID_FOR)
            && !c_parser_next_token_is_keyword (parser, RID_WHILE)
            && !c_parser_next_token_is_keyword (parser, RID_DO))
          {
            c_parser_error (parser, "for, while or do statement expected");
            return false;
          }
        if (c_parser_next_token_is_keyword (parser, RID_FOR))
          c_parser_for_statement (parser, ivdep, unroll, novector, if_p);
        else if (c_parser_next_token_is_keyword (parser, RID_WHILE))
          c_parser_while_statement (parser, ivdep, unroll, novector, if_p);
        else
          c_parser_do_statement (parser, ivdep, unroll, novector);
      }
      return true;

    case PRAGMA_GCC_PCH_PREPROCESS:
      c_parser_error (parser, "%<#pragma GCC pch_preprocess%> must be first");
      c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
      return false;

    case PRAGMA_OACC_WAIT:
      if (context != pragma_compound)
        {
          construct = "acc wait";
          goto in_compound;
        }
        /* FALL THROUGH.  */

    default:
      if (id < PRAGMA_FIRST_EXTERNAL)
        {
          if (context != pragma_stmt && context != pragma_compound)
            {
            bad_stmt:
              c_parser_error (parser, "expected declaration specifiers");
              c_parser_skip_until_found (parser, CPP_PRAGMA_EOL, NULL);
              return false;
            }
          c_parser_omp_construct (parser, if_p);
          return true;
        }
      break;
    }

  c_parser_consume_pragma (parser);
  c_invoke_pragma_handler (id);

  /* Skip to EOL, but suppress any error message.  Those will have been
     generated by the handler routine through calling error, as opposed
     to calling c_parser_error.  */
  parser->error = true;
  c_parser_skip_to_pragma_eol (parser);

  return false;
}

/* The interface the pragma parsers have to the lexer.  */

enum cpp_ttype
pragma_lex (tree *value, location_t *loc)
{
  c_token *tok = c_parser_peek_token (the_parser);
  enum cpp_ttype ret = tok->type;

  *value = tok->value;
  if (loc)
    *loc = tok->location;

  if (ret == CPP_PRAGMA_EOL || ret == CPP_EOF)
    ret = CPP_EOF;
  else if (ret == CPP_STRING)
    *value = c_parser_string_literal (the_parser, false, false).value;
  else
    {
      if (ret == CPP_KEYWORD)
        ret = CPP_NAME;
      c_parser_consume_token (the_parser);
    }

  return ret;
}

void
pragma_lex_discard_to_eol ()
{
  cpp_ttype type;
  do
    {
      type = c_parser_peek_token (the_parser)->type;
      gcc_assert (type != CPP_EOF);
      c_parser_consume_token (the_parser);
    } while (type != CPP_PRAGMA_EOL);
}

static void
c_parser_pragma_pch_preprocess (c_parser *parser)
{
  tree name = NULL;

  parser->lex_joined_string = true;
  c_parser_consume_pragma (parser);
  if (c_parser_next_token_is (parser, CPP_STRING))
    {
      name = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);
    }
  else
    c_parser_error (parser, "expected string literal");
  c_parser_skip_to_pragma_eol (parser);
  parser->lex_joined_string = false;

  if (name)
    c_common_pch_pragma (parse_in, TREE_STRING_POINTER (name));
}
\f
/* OpenACC and OpenMP parsing routines.  */

/* Returns name of the next clause.
   If the clause is not recognized PRAGMA_OMP_CLAUSE_NONE is returned and
   the token is not consumed.  Otherwise appropriate pragma_omp_clause is
   returned and the token is consumed.  */

static pragma_omp_clause
c_parser_omp_clause_name (c_parser *parser)
{
  pragma_omp_clause result = PRAGMA_OMP_CLAUSE_NONE;

  if (c_parser_next_token_is_keyword (parser, RID_AUTO))
    result = PRAGMA_OACC_CLAUSE_AUTO;
  else if (c_parser_next_token_is_keyword (parser, RID_IF))
    result = PRAGMA_OMP_CLAUSE_IF;
  else if (c_parser_next_token_is_keyword (parser, RID_DEFAULT))
    result = PRAGMA_OMP_CLAUSE_DEFAULT;
  else if (c_parser_next_token_is_keyword (parser, RID_FOR))
    result = PRAGMA_OMP_CLAUSE_FOR;
  else if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      switch (p[0])
        {
        case 'a':
          if (!strcmp ("affinity", p))
            result = PRAGMA_OMP_CLAUSE_AFFINITY;
          else if (!strcmp ("aligned", p))
            result = PRAGMA_OMP_CLAUSE_ALIGNED;
          else if (!strcmp ("allocate", p))
            result = PRAGMA_OMP_CLAUSE_ALLOCATE;
          else if (!strcmp ("async", p))
            result = PRAGMA_OACC_CLAUSE_ASYNC;
          else if (!strcmp ("attach", p))
            result = PRAGMA_OACC_CLAUSE_ATTACH;
          break;
        case 'b':
          if (!strcmp ("bind", p))
            result = PRAGMA_OMP_CLAUSE_BIND;
          break;
        case 'c':
          if (!strcmp ("collapse", p))
            result = PRAGMA_OMP_CLAUSE_COLLAPSE;
          else if (!strcmp ("copy", p))
            result = PRAGMA_OACC_CLAUSE_COPY;
          else if (!strcmp ("copyin", p))
            result = PRAGMA_OMP_CLAUSE_COPYIN;
          else if (!strcmp ("copyout", p))
            result = PRAGMA_OACC_CLAUSE_COPYOUT;
          else if (!strcmp ("copyprivate", p))
            result = PRAGMA_OMP_CLAUSE_COPYPRIVATE;
          else if (!strcmp ("create", p))
            result = PRAGMA_OACC_CLAUSE_CREATE;
          break;
        case 'd':
          if (!strcmp ("defaultmap", p))
            result = PRAGMA_OMP_CLAUSE_DEFAULTMAP;
          else if (!strcmp ("delete", p))
            result = PRAGMA_OACC_CLAUSE_DELETE;
          else if (!strcmp ("depend", p))
            result = PRAGMA_OMP_CLAUSE_DEPEND;
          else if (!strcmp ("detach", p))
            result = PRAGMA_OACC_CLAUSE_DETACH;
          else if (!strcmp ("device", p))
            result = PRAGMA_OMP_CLAUSE_DEVICE;
          else if (!strcmp ("deviceptr", p))
            result = PRAGMA_OACC_CLAUSE_DEVICEPTR;
          else if (!strcmp ("device_resident", p))
            result = PRAGMA_OACC_CLAUSE_DEVICE_RESIDENT;
          else if (!strcmp ("device_type", p))
            result = PRAGMA_OMP_CLAUSE_DEVICE_TYPE;
          else if (!strcmp ("dist_schedule", p))
            result = PRAGMA_OMP_CLAUSE_DIST_SCHEDULE;
          else if (!strcmp ("doacross", p))
            result = PRAGMA_OMP_CLAUSE_DOACROSS;
          break;
        case 'e':
          if (!strcmp ("enter", p))
            result = PRAGMA_OMP_CLAUSE_ENTER;
          break;
        case 'f':
          if (!strcmp ("filter", p))
            result = PRAGMA_OMP_CLAUSE_FILTER;
          else if (!strcmp ("final", p))
            result = PRAGMA_OMP_CLAUSE_FINAL;
          else if (!strcmp ("finalize", p))
            result = PRAGMA_OACC_CLAUSE_FINALIZE;
          else if (!strcmp ("firstprivate", p))
            result = PRAGMA_OMP_CLAUSE_FIRSTPRIVATE;
          else if (!strcmp ("from", p))
            result = PRAGMA_OMP_CLAUSE_FROM;
          break;
        case 'g':
          if (!strcmp ("gang", p))
            result = PRAGMA_OACC_CLAUSE_GANG;
          else if (!strcmp ("grainsize", p))
            result = PRAGMA_OMP_CLAUSE_GRAINSIZE;
          break;
        case 'h':
          if (!strcmp ("has_device_addr", p))
            result = PRAGMA_OMP_CLAUSE_HAS_DEVICE_ADDR;
          else if (!strcmp ("hint", p))
            result = PRAGMA_OMP_CLAUSE_HINT;
          else if (!strcmp ("host", p))
            result = PRAGMA_OACC_CLAUSE_HOST;
          break;
        case 'i':
          if (!strcmp ("if_present", p))
            result = PRAGMA_OACC_CLAUSE_IF_PRESENT;
          else if (!strcmp ("in_reduction", p))
            result = PRAGMA_OMP_CLAUSE_IN_REDUCTION;
          else if (!strcmp ("inbranch", p))
            result = PRAGMA_OMP_CLAUSE_INBRANCH;
          else if (!strcmp ("independent", p))
            result = PRAGMA_OACC_CLAUSE_INDEPENDENT;
          else if (!strcmp ("indirect", p))
            result = PRAGMA_OMP_CLAUSE_INDIRECT;
          else if (!strcmp ("is_device_ptr", p))
            result = PRAGMA_OMP_CLAUSE_IS_DEVICE_PTR;
          break;
        case 'l':
          if (!strcmp ("lastprivate", p))
            result = PRAGMA_OMP_CLAUSE_LASTPRIVATE;
          else if (!strcmp ("linear", p))
            result = PRAGMA_OMP_CLAUSE_LINEAR;
          else if (!strcmp ("link", p))
            result = PRAGMA_OMP_CLAUSE_LINK;
          break;
        case 'm':
          if (!strcmp ("map", p))
            result = PRAGMA_OMP_CLAUSE_MAP;
          else if (!strcmp ("mergeable", p))
            result = PRAGMA_OMP_CLAUSE_MERGEABLE;
          break;
        case 'n':
          if (!strcmp ("no_create", p))
            result = PRAGMA_OACC_CLAUSE_NO_CREATE;
          else if (!strcmp ("nogroup", p))
            result = PRAGMA_OMP_CLAUSE_NOGROUP;
          else if (!strcmp ("nohost", p))
            result = PRAGMA_OACC_CLAUSE_NOHOST;
          else if (!strcmp ("nontemporal", p))
            result = PRAGMA_OMP_CLAUSE_NONTEMPORAL;
          else if (!strcmp ("notinbranch", p))
            result = PRAGMA_OMP_CLAUSE_NOTINBRANCH;
          else if (!strcmp ("nowait", p))
            result = PRAGMA_OMP_CLAUSE_NOWAIT;
          else if (!strcmp ("num_gangs", p))
            result = PRAGMA_OACC_CLAUSE_NUM_GANGS;
          else if (!strcmp ("num_tasks", p))
            result = PRAGMA_OMP_CLAUSE_NUM_TASKS;
          else if (!strcmp ("num_teams", p))
            result = PRAGMA_OMP_CLAUSE_NUM_TEAMS;
          else if (!strcmp ("num_threads", p))
            result = PRAGMA_OMP_CLAUSE_NUM_THREADS;
          else if (!strcmp ("num_workers", p))
            result = PRAGMA_OACC_CLAUSE_NUM_WORKERS;
          break;
        case 'o':
          if (!strcmp ("ordered", p))
            result = PRAGMA_OMP_CLAUSE_ORDERED;
          else if (!strcmp ("order", p))
            result = PRAGMA_OMP_CLAUSE_ORDER;
          break;
        case 'p':
          if (!strcmp ("parallel", p))
            result = PRAGMA_OMP_CLAUSE_PARALLEL;
          else if (!strcmp ("present", p))
            result = PRAGMA_OACC_CLAUSE_PRESENT;
          /* As of OpenACC 2.5, these are now aliases of the non-present_or
             clauses.  */
          else if (!strcmp ("present_or_copy", p)
                   || !strcmp ("pcopy", p))
            result = PRAGMA_OACC_CLAUSE_COPY;
          else if (!strcmp ("present_or_copyin", p)
                   || !strcmp ("pcopyin", p))
            result = PRAGMA_OACC_CLAUSE_COPYIN;
          else if (!strcmp ("present_or_copyout", p)
                   || !strcmp ("pcopyout", p))
            result = PRAGMA_OACC_CLAUSE_COPYOUT;
          else if (!strcmp ("present_or_create", p)
                   || !strcmp ("pcreate", p))
            result = PRAGMA_OACC_CLAUSE_CREATE;
          else if (!strcmp ("priority", p))
            result = PRAGMA_OMP_CLAUSE_PRIORITY;
          else if (!strcmp ("private", p))
            result = PRAGMA_OMP_CLAUSE_PRIVATE;
          else if (!strcmp ("proc_bind", p))
            result = PRAGMA_OMP_CLAUSE_PROC_BIND;
          break;
        case 'r':
          if (!strcmp ("reduction", p))
            result = PRAGMA_OMP_CLAUSE_REDUCTION;
          break;
        case 's':
          if (!strcmp ("safelen", p))
            result = PRAGMA_OMP_CLAUSE_SAFELEN;
          else if (!strcmp ("schedule", p))
            result = PRAGMA_OMP_CLAUSE_SCHEDULE;
          else if (!strcmp ("sections", p))
            result = PRAGMA_OMP_CLAUSE_SECTIONS;
          else if (!strcmp ("self", p))
            result = PRAGMA_OACC_CLAUSE_SELF;
          else if (!strcmp ("seq", p))
            result = PRAGMA_OACC_CLAUSE_SEQ;
          else if (!strcmp ("shared", p))
            result = PRAGMA_OMP_CLAUSE_SHARED;
          else if (!strcmp ("simd", p))
            result = PRAGMA_OMP_CLAUSE_SIMD;
          else if (!strcmp ("simdlen", p))
            result = PRAGMA_OMP_CLAUSE_SIMDLEN;
          break;
        case 't':
          if (!strcmp ("task_reduction", p))
            result = PRAGMA_OMP_CLAUSE_TASK_REDUCTION;
          else if (!strcmp ("taskgroup", p))
            result = PRAGMA_OMP_CLAUSE_TASKGROUP;
          else if (!strcmp ("thread_limit", p))
            result = PRAGMA_OMP_CLAUSE_THREAD_LIMIT;
          else if (!strcmp ("threads", p))
            result = PRAGMA_OMP_CLAUSE_THREADS;
          else if (!strcmp ("tile", p))
            result = PRAGMA_OACC_CLAUSE_TILE;
          else if (!strcmp ("to", p))
            result = PRAGMA_OMP_CLAUSE_TO;
          break;
        case 'u':
          if (!strcmp ("uniform", p))
            result = PRAGMA_OMP_CLAUSE_UNIFORM;
          else if (!strcmp ("untied", p))
            result = PRAGMA_OMP_CLAUSE_UNTIED;
          else if (!strcmp ("use_device", p))
            result = PRAGMA_OACC_CLAUSE_USE_DEVICE;
          else if (!strcmp ("use_device_addr", p))
            result = PRAGMA_OMP_CLAUSE_USE_DEVICE_ADDR;
          else if (!strcmp ("use_device_ptr", p))
            result = PRAGMA_OMP_CLAUSE_USE_DEVICE_PTR;
          break;
        case 'v':
          if (!strcmp ("vector", p))
            result = PRAGMA_OACC_CLAUSE_VECTOR;
          else if (!strcmp ("vector_length", p))
            result = PRAGMA_OACC_CLAUSE_VECTOR_LENGTH;
          break;
        case 'w':
          if (!strcmp ("wait", p))
            result = PRAGMA_OACC_CLAUSE_WAIT;
          else if (!strcmp ("worker", p))
            result = PRAGMA_OACC_CLAUSE_WORKER;
          break;
        }
    }

  if (result != PRAGMA_OMP_CLAUSE_NONE)
    c_parser_consume_token (parser);

  return result;
}

/* Validate that a clause of the given type does not already exist.  */

static void
check_no_duplicate_clause (tree clauses, enum omp_clause_code code,
                           const char *name)
{
  if (tree c = omp_find_clause (clauses, code))
    error_at (OMP_CLAUSE_LOCATION (c), "too many %qs clauses", name);
}

/* OpenACC 2.0
   Parse wait clause or wait directive parameters.  */

static tree
c_parser_oacc_wait_list (c_parser *parser, location_t clause_loc, tree list)
{
  vec<tree, va_gc> *args;
  tree t, args_tree;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  args = c_parser_expr_list (parser, false, true, NULL, NULL, NULL, NULL);
  args_tree = build_tree_list_vec (args);

  for (t = args_tree; t; t = TREE_CHAIN (t))
    {
      tree targ = TREE_VALUE (t);

      if (targ != error_mark_node)
        {
          if (!INTEGRAL_TYPE_P (TREE_TYPE (targ)))
            {
              c_parser_error (parser, "expression must be integral");
              targ = error_mark_node;
            }
          else
            {
              tree c = build_omp_clause (clause_loc, OMP_CLAUSE_WAIT);

              OMP_CLAUSE_DECL (c) = targ;
              OMP_CLAUSE_CHAIN (c) = list;
              list = c;
            }
        }
    }

  release_tree_vector (args);
  parens.require_close (parser);
  return list;
}

/* OpenACC 2.0, OpenMP 2.5:
   variable-list:
     identifier
     variable-list , identifier

   If KIND is nonzero, create the appropriate node and install the
   decl in OMP_CLAUSE_DECL and add the node to the head of the list.
   If KIND is nonzero, CLAUSE_LOC is the location of the clause.

   If KIND is zero, create a TREE_LIST with the decl in TREE_PURPOSE;
   return the list created.

   The optional ALLOW_DEREF argument is true if list items can use the deref
   (->) operator.  */

struct omp_dim
{
  tree low_bound, length;
  location_t loc;
  bool no_colon;
  omp_dim (tree lb, tree len, location_t lo, bool nc)
  : low_bound (lb), length (len), loc (lo), no_colon (nc) {}
};

static tree
c_parser_omp_variable_list (c_parser *parser,
                            location_t clause_loc,
                            enum omp_clause_code kind, tree list,
                            bool map_lvalue = false)
{
  auto_vec<omp_dim> dims;
  bool array_section_p;
  auto_vec<c_token> tokens;
  unsigned int tokens_avail = 0;
  c_token *saved_tokens = NULL;
  bool first = true;

  while (1)
    {
      tree t = NULL_TREE;

      if (kind == OMP_CLAUSE_DEPEND || kind == OMP_CLAUSE_AFFINITY)
        {
          if (c_parser_next_token_is_not (parser, CPP_NAME)
              || c_parser_peek_token (parser)->id_kind != C_ID_ID)
            {
              struct c_expr expr;
              if (kind == OMP_CLAUSE_DEPEND
                  && c_parser_next_token_is_keyword (parser,
                                                     RID_OMP_ALL_MEMORY)
                  && (c_parser_peek_2nd_token (parser)->type == CPP_COMMA
                      || (c_parser_peek_2nd_token (parser)->type
                          == CPP_CLOSE_PAREN)))
                {
                  expr.value = ridpointers[RID_OMP_ALL_MEMORY];
                  c_parser_consume_token (parser);
                }
              else
                expr = c_parser_expr_no_commas (parser, NULL);
              if (expr.value != error_mark_node)
                {
                  tree u = build_omp_clause (clause_loc, kind);
                  OMP_CLAUSE_DECL (u) = expr.value;
                  OMP_CLAUSE_CHAIN (u) = list;
                  list = u;
                }

              if (c_parser_next_token_is_not (parser, CPP_COMMA))
                break;

              c_parser_consume_token (parser);
              first = false;
              continue;
            }

          tokens.truncate (0);
          unsigned int nesting_depth = 0;
          while (1)
            {
              c_token *token = c_parser_peek_token (parser);
              switch (token->type)
                {
                case CPP_EOF:
                case CPP_PRAGMA_EOL:
                  break;
                case CPP_OPEN_BRACE:
                case CPP_OPEN_PAREN:
                case CPP_OPEN_SQUARE:
                  ++nesting_depth;
                  goto add;
                case CPP_CLOSE_BRACE:
                case CPP_CLOSE_PAREN:
                case CPP_CLOSE_SQUARE:
                  if (nesting_depth-- == 0)
                    break;
                  goto add;
                case CPP_COMMA:
                  if (nesting_depth == 0)
                    break;
                  goto add;
                default:
                add:
                  tokens.safe_push (*token);
                  c_parser_consume_token (parser);
                  continue;
                }
              break;
            }

          /* Make sure nothing tries to read past the end of the tokens.  */
          c_token eof_token;
          memset (&eof_token, 0, sizeof (eof_token));
          eof_token.type = CPP_EOF;
          tokens.safe_push (eof_token);
          tokens.safe_push (eof_token);

          saved_tokens = parser->tokens;
          tokens_avail = parser->tokens_avail;
          parser->tokens = tokens.address ();
          parser->tokens_avail = tokens.length ();
        }
      else if (map_lvalue
               && (kind == OMP_CLAUSE_MAP
                   || kind == OMP_CLAUSE_TO
                   || kind == OMP_CLAUSE_FROM))
        {
          location_t loc = c_parser_peek_token (parser)->location;
          bool save_c_omp_array_section_p = c_omp_array_section_p;
          c_omp_array_section_p = true;
          c_expr expr = c_parser_expr_no_commas (parser, NULL);
          if (expr.value != error_mark_node)
            mark_exp_read (expr.value);
          c_omp_array_section_p = save_c_omp_array_section_p;
          tree decl = expr.value;

         /* This code rewrites a parsed expression containing various tree
            codes used to represent array accesses into a more uniform nest of
            OMP_ARRAY_SECTION nodes before it is processed by
            c-typeck.cc:handle_omp_array_sections_1.  It might be more
            efficient to move this logic to that function instead, analysing
            the parsed expression directly rather than this preprocessed
            form.  (See also equivalent code in cp/parser.cc,
            cp/semantics.cc).  */
          dims.truncate (0);
          if (TREE_CODE (decl) == OMP_ARRAY_SECTION)
            {
              while (TREE_CODE (decl) == OMP_ARRAY_SECTION)
                {
                  tree low_bound = TREE_OPERAND (decl, 1);
                  tree length = TREE_OPERAND (decl, 2);
                  dims.safe_push (omp_dim (low_bound, length, loc, false));
                  decl = TREE_OPERAND (decl, 0);
                }

              while (TREE_CODE (decl) == ARRAY_REF
                     || TREE_CODE (decl) == INDIRECT_REF
                     || TREE_CODE (decl) == COMPOUND_EXPR)
                {
                  if (TREE_CODE (decl) == COMPOUND_EXPR)
                    {
                      decl = TREE_OPERAND (decl, 1);
                      STRIP_NOPS (decl);
                    }
                  else if (TREE_CODE (decl) == INDIRECT_REF)
                    {
                      dims.safe_push (omp_dim (integer_zero_node,
                                               integer_one_node, loc, true));
                      decl = TREE_OPERAND (decl, 0);
                    }
                  else  /* ARRAY_REF. */
                    {
                      tree index = TREE_OPERAND (decl, 1);
                      dims.safe_push (omp_dim (index, integer_one_node, loc,
                                               true));
                      decl = TREE_OPERAND (decl, 0);
                    }
                }

              for (int i = dims.length () - 1; i >= 0; i--)
                decl = build_omp_array_section (loc,  decl, dims[i].low_bound,
                                                dims[i].length);
            }
          else if (TREE_CODE (decl) == INDIRECT_REF)
            {
              /* Turn indirection of a pointer "*foo" into "foo[0:1]".  */
              decl = TREE_OPERAND (decl, 0);
              STRIP_NOPS (decl);

              decl = build_omp_array_section (loc, decl, integer_zero_node,
                                              integer_one_node);
            }
          else if (TREE_CODE (decl) == ARRAY_REF)
            {
              tree idx = TREE_OPERAND (decl, 1);

              decl = TREE_OPERAND (decl, 0);
              STRIP_NOPS (decl);

              decl = build_omp_array_section (loc, decl, idx, integer_one_node);
            }
          else if (TREE_CODE (decl) == NON_LVALUE_EXPR
                   || CONVERT_EXPR_P (decl))
            decl = TREE_OPERAND (decl, 0);

          tree u = build_omp_clause (clause_loc, kind);
          OMP_CLAUSE_DECL (u) = decl;
          OMP_CLAUSE_CHAIN (u) = list;
          list = u;

          goto next_item;
        }

      if (c_parser_next_token_is (parser, CPP_NAME)
          && c_parser_peek_token (parser)->id_kind == C_ID_ID)
        {
          t = lookup_name (c_parser_peek_token (parser)->value);

          if (t == NULL_TREE)
            {
              undeclared_variable (c_parser_peek_token (parser)->location,
              c_parser_peek_token (parser)->value);
              t = error_mark_node;
            }

          c_parser_consume_token (parser);
        }
      else if (c_parser_next_token_is (parser, CPP_KEYWORD)
               && (c_parser_peek_token (parser)->keyword == RID_FUNCTION_NAME
                   || (c_parser_peek_token (parser)->keyword
                       == RID_PRETTY_FUNCTION_NAME)
                   || (c_parser_peek_token (parser)->keyword
                       == RID_C99_FUNCTION_NAME)))
        t = c_parser_predefined_identifier (parser).value;
      else
        {
          if (first)
            c_parser_error (parser, "expected identifier");
          break;
        }

      if (t == error_mark_node)
        ;
      else if (kind != 0)
        {
          switch (kind)
            {
            case OMP_CLAUSE__CACHE_:
              /* The OpenACC cache directive explicitly only allows "array
                 elements or subarrays".  */
              if (c_parser_peek_token (parser)->type != CPP_OPEN_SQUARE)
                {
                  c_parser_error (parser, "expected %<[%>");
                  t = error_mark_node;
                  break;
                }
              /* FALLTHROUGH  */
            case OMP_CLAUSE_MAP:
            case OMP_CLAUSE_FROM:
            case OMP_CLAUSE_TO:
            start_component_ref:
              while (c_parser_next_token_is (parser, CPP_DOT)
                     || c_parser_next_token_is (parser, CPP_DEREF))
                {
                  location_t op_loc = c_parser_peek_token (parser)->location;
                  location_t arrow_loc = UNKNOWN_LOCATION;
                  if (c_parser_next_token_is (parser, CPP_DEREF))
                    {
                      c_expr t_expr;
                      t_expr.value = t;
                      t_expr.original_code = ERROR_MARK;
                      t_expr.original_type = NULL;
                      set_c_expr_source_range (&t_expr, op_loc, op_loc);
                      t_expr.m_decimal = 0;
                      t_expr = convert_lvalue_to_rvalue (op_loc, t_expr,
                                                         true, false);
                      t = build_indirect_ref (op_loc, t_expr.value, RO_ARROW);
                      arrow_loc = t_expr.get_location ();
                    }
                  c_parser_consume_token (parser);
                  if (!c_parser_next_token_is (parser, CPP_NAME))
                    {
                      c_parser_error (parser, "expected identifier");
                      t = error_mark_node;
                      break;
                    }

                  c_token *comp_tok = c_parser_peek_token (parser);
                  tree ident = comp_tok->value;
                  location_t comp_loc = comp_tok->location;
                  c_parser_consume_token (parser);
                  t = build_component_ref (op_loc, t, ident, comp_loc,
                                           arrow_loc);
                }
              /* FALLTHROUGH  */
            case OMP_CLAUSE_AFFINITY:
            case OMP_CLAUSE_DEPEND:
            case OMP_CLAUSE_REDUCTION:
            case OMP_CLAUSE_IN_REDUCTION:
            case OMP_CLAUSE_TASK_REDUCTION:
            case OMP_CLAUSE_HAS_DEVICE_ADDR:
              array_section_p = false;
              dims.truncate (0);
              while (c_parser_next_token_is (parser, CPP_OPEN_SQUARE))
                {
                  location_t loc = UNKNOWN_LOCATION;
                  tree low_bound = NULL_TREE, length = NULL_TREE;
                  bool no_colon = false;

                  c_parser_consume_token (parser);
                  if (!c_parser_next_token_is (parser, CPP_COLON))
                    {
                      location_t expr_loc
                        = c_parser_peek_token (parser)->location;
                      c_expr expr = c_parser_expression (parser);
                      expr = convert_lvalue_to_rvalue (expr_loc, expr,
                                                       false, true);
                      low_bound = expr.value;
                      loc = expr_loc;
                    }
                  if (c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
                    {
                      length = integer_one_node;
                      no_colon = true;
                    }
                  else
                    {
                      /* Look for `:'.  */
                      if (!c_parser_require (parser, CPP_COLON,
                                             "expected %<:%>"))
                        {
                          t = error_mark_node;
                          break;
                        }
                      array_section_p = true;
                      if (!c_parser_next_token_is (parser, CPP_CLOSE_SQUARE))
                        {
                          location_t expr_loc
                            = c_parser_peek_token (parser)->location;
                          c_expr expr = c_parser_expression (parser);
                          expr = convert_lvalue_to_rvalue (expr_loc, expr,
                                                           false, true);
                          length = expr.value;
                        }
                    }
                  /* Look for the closing `]'.  */
                  if (!c_parser_require (parser, CPP_CLOSE_SQUARE,
                                         "expected %<]%>"))
                    {
                      t = error_mark_node;
                      break;
                    }

                  dims.safe_push (omp_dim (low_bound, length, loc, no_colon));
                }

              if (t != error_mark_node)
                {
                  if ((kind == OMP_CLAUSE_MAP
                       || kind == OMP_CLAUSE_FROM
                       || kind == OMP_CLAUSE_TO)
                      && !array_section_p
                      && (c_parser_next_token_is (parser, CPP_DOT)
                          || c_parser_next_token_is (parser, CPP_DEREF)))
                    {
                      for (unsigned i = 0; i < dims.length (); i++)
                        {
                          gcc_assert (dims[i].length == integer_one_node);
                          t = build_array_ref (dims[i].loc,
                                               t, dims[i].low_bound);
                        }
                      goto start_component_ref;
                    }
                  else
                    for (unsigned i = 0; i < dims.length (); i++)
                      t = build_omp_array_section (clause_loc, t,
                                                   dims[i].low_bound,
                                                   dims[i].length);
                }

              if ((kind == OMP_CLAUSE_DEPEND || kind == OMP_CLAUSE_AFFINITY)
                  && t != error_mark_node
                  && parser->tokens_avail != 2)
                {
                  if (array_section_p)
                    {
                      error_at (c_parser_peek_token (parser)->location,
                                "expected %<)%> or %<,%>");
                      t = error_mark_node;
                    }
                  else
                    {
                      parser->tokens = tokens.address ();
                      parser->tokens_avail = tokens.length ();

                      t = c_parser_expr_no_commas (parser, NULL).value;
                      if (t != error_mark_node && parser->tokens_avail != 2)
                        {
                          error_at (c_parser_peek_token (parser)->location,
                                    "expected %<)%> or %<,%>");
                          t = error_mark_node;
                        }
                    }
                }
              break;
            default:
              break;
            }

          if (t != error_mark_node)
            {
              tree u = build_omp_clause (clause_loc, kind);
              OMP_CLAUSE_DECL (u) = t;
              OMP_CLAUSE_CHAIN (u) = list;
              list = u;
            }
        }
      else
        list = tree_cons (t, NULL_TREE, list);

      if (kind == OMP_CLAUSE_DEPEND || kind == OMP_CLAUSE_AFFINITY)
        {
          parser->tokens = saved_tokens;
          parser->tokens_avail = tokens_avail;
        }

    next_item:
      if (c_parser_next_token_is_not (parser, CPP_COMMA))
        break;

      c_parser_consume_token (parser);
      first = false;
    }

  return list;
}

/* Similarly, but expect leading and trailing parenthesis.  This is a very
   common case for OpenACC and OpenMP clauses.  The optional ALLOW_DEREF
   argument is true if list items can use the deref (->) operator.  */

static tree
c_parser_omp_var_list_parens (c_parser *parser, enum omp_clause_code kind,
                              tree list, bool map_lvalue = false)
{
  /* The clauses location.  */
  location_t loc = c_parser_peek_token (parser)->location;

  if (parser->in_omp_decl_attribute)
    {
      if (kind)
        {
          tree u = build_omp_clause (loc, kind);
          OMP_CLAUSE_DECL (u) = parser->in_omp_decl_attribute;
          OMP_CLAUSE_CHAIN (u) = list;
          return u;
        }
      else
        return tree_cons (parser->in_omp_decl_attribute, NULL_TREE, list);
    }

  matching_parens parens;
  if (parens.require_open (parser))
    {
      list = c_parser_omp_variable_list (parser, loc, kind, list, map_lvalue);
      parens.skip_until_found_close (parser);
    }
  return list;
}

/* OpenACC 2.0:
   copy ( variable-list )
   copyin ( variable-list )
   copyout ( variable-list )
   create ( variable-list )
   delete ( variable-list )
   present ( variable-list )

   OpenACC 2.6:
   no_create ( variable-list )
   attach ( variable-list )
   detach ( variable-list ) */

static tree
c_parser_oacc_data_clause (c_parser *parser, pragma_omp_clause c_kind,
                           tree list)
{
  enum gomp_map_kind kind;
  switch (c_kind)
    {
    case PRAGMA_OACC_CLAUSE_ATTACH:
      kind = GOMP_MAP_ATTACH;
      break;
    case PRAGMA_OACC_CLAUSE_COPY:
      kind = GOMP_MAP_TOFROM;
      break;
    case PRAGMA_OACC_CLAUSE_COPYIN:
      kind = GOMP_MAP_TO;
      break;
    case PRAGMA_OACC_CLAUSE_COPYOUT:
      kind = GOMP_MAP_FROM;
      break;
    case PRAGMA_OACC_CLAUSE_CREATE:
      kind = GOMP_MAP_ALLOC;
      break;
    case PRAGMA_OACC_CLAUSE_DELETE:
      kind = GOMP_MAP_RELEASE;
      break;
    case PRAGMA_OACC_CLAUSE_DETACH:
      kind = GOMP_MAP_DETACH;
      break;
    case PRAGMA_OACC_CLAUSE_DEVICE:
      kind = GOMP_MAP_FORCE_TO;
      break;
    case PRAGMA_OACC_CLAUSE_DEVICE_RESIDENT:
      kind = GOMP_MAP_DEVICE_RESIDENT;
      break;
    case PRAGMA_OACC_CLAUSE_LINK:
      kind = GOMP_MAP_LINK;
      break;
    case PRAGMA_OACC_CLAUSE_NO_CREATE:
      kind = GOMP_MAP_IF_PRESENT;
      break;
    case PRAGMA_OACC_CLAUSE_PRESENT:
      kind = GOMP_MAP_FORCE_PRESENT;
      break;
    case PRAGMA_OACC_CLAUSE_SELF:
      /* "The 'host' clause is a synonym for the 'self' clause."  */
    case PRAGMA_OACC_CLAUSE_HOST:
      kind = GOMP_MAP_FORCE_FROM;
      break;
    default:
      gcc_unreachable ();
    }
  tree nl, c;
  nl = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_MAP, list, false);

  for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
    OMP_CLAUSE_SET_MAP_KIND (c, kind);

  return nl;
}

/* OpenACC 2.0:
   deviceptr ( variable-list ) */

static tree
c_parser_oacc_data_clause_deviceptr (c_parser *parser, tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree vars, t;

  /* Can't use OMP_CLAUSE_MAP here (that is, can't use the generic
     c_parser_oacc_data_clause), as for PRAGMA_OACC_CLAUSE_DEVICEPTR,
     variable-list must only allow for pointer variables.  */
  vars = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ERROR, NULL);
  for (t = vars; t && t; t = TREE_CHAIN (t))
    {
      tree v = TREE_PURPOSE (t);

      /* FIXME diagnostics: Ideally we should keep individual
         locations for all the variables in the var list to make the
         following errors more precise.  Perhaps
         c_parser_omp_var_list_parens() should construct a list of
         locations to go along with the var list.  */

      if (!VAR_P (v) && TREE_CODE (v) != PARM_DECL)
        error_at (loc, "%qD is not a variable", v);
      else if (TREE_TYPE (v) == error_mark_node)
        ;
      else if (!POINTER_TYPE_P (TREE_TYPE (v)))
        error_at (loc, "%qD is not a pointer variable", v);

      tree u = build_omp_clause (loc, OMP_CLAUSE_MAP);
      OMP_CLAUSE_SET_MAP_KIND (u, GOMP_MAP_FORCE_DEVICEPTR);
      OMP_CLAUSE_DECL (u) = v;
      OMP_CLAUSE_CHAIN (u) = list;
      list = u;
    }

  return list;
}

/* OpenACC 2.0, OpenMP 3.0:
   collapse ( constant-expression ) */

static tree
c_parser_omp_clause_collapse (c_parser *parser, tree list)
{
  tree c, num = error_mark_node;
  HOST_WIDE_INT n;
  location_t loc;

  check_no_duplicate_clause (list, OMP_CLAUSE_COLLAPSE, "collapse");
  check_no_duplicate_clause (list, OMP_CLAUSE_TILE, "tile");

  loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      num = c_parser_expr_no_commas (parser, NULL).value;
      parens.skip_until_found_close (parser);
    }
  if (num == error_mark_node)
    return list;
  mark_exp_read (num);
  num = c_fully_fold (num, false, NULL);
  if (!INTEGRAL_TYPE_P (TREE_TYPE (num))
      || !tree_fits_shwi_p (num)
      || (n = tree_to_shwi (num)) <= 0
      || (int) n != n)
    {
      error_at (loc,
                "collapse argument needs positive constant integer expression");
      return list;
    }
  c = build_omp_clause (loc, OMP_CLAUSE_COLLAPSE);
  OMP_CLAUSE_COLLAPSE_EXPR (c) = num;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 2.5:
   copyin ( variable-list ) */

static tree
c_parser_omp_clause_copyin (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_COPYIN, list);
}

/* OpenMP 2.5:
   copyprivate ( variable-list ) */

static tree
c_parser_omp_clause_copyprivate (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_COPYPRIVATE, list);
}

/* OpenMP 2.5:
   default ( none | shared )

   OpenMP 5.1:
   default ( private | firstprivate )

   OpenACC:
   default ( none | present ) */

static tree
c_parser_omp_clause_default (c_parser *parser, tree list, bool is_oacc)
{
  enum omp_clause_default_kind kind = OMP_CLAUSE_DEFAULT_UNSPECIFIED;
  location_t loc = c_parser_peek_token (parser)->location;
  tree c;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      switch (p[0])
        {
        case 'n':
          if (strcmp ("none", p) != 0)
            goto invalid_kind;
          kind = OMP_CLAUSE_DEFAULT_NONE;
          break;

        case 'p':
          if (is_oacc)
            {
              if (strcmp ("present", p) != 0)
                goto invalid_kind;
              kind = OMP_CLAUSE_DEFAULT_PRESENT;
            }
          else
            {
              if (strcmp ("private", p) != 0)
                goto invalid_kind;
              kind = OMP_CLAUSE_DEFAULT_PRIVATE;
            }
          break;

        case 'f':
          if (strcmp ("firstprivate", p) != 0 || is_oacc)
            goto invalid_kind;
          kind = OMP_CLAUSE_DEFAULT_FIRSTPRIVATE;
          break;

        case 's':
          if (strcmp ("shared", p) != 0 || is_oacc)
            goto invalid_kind;
          kind = OMP_CLAUSE_DEFAULT_SHARED;
          break;

        default:
          goto invalid_kind;
        }

      c_parser_consume_token (parser);
    }
  else
    {
    invalid_kind:
      if (is_oacc)
        c_parser_error (parser, "expected %<none%> or %<present%>");
      else
        c_parser_error (parser, "expected %<none%>, %<shared%>, "
                                "%<private%> or %<firstprivate%>");
    }
  parens.skip_until_found_close (parser);

  if (kind == OMP_CLAUSE_DEFAULT_UNSPECIFIED)
    return list;

  check_no_duplicate_clause (list, OMP_CLAUSE_DEFAULT, "default");
  c = build_omp_clause (loc, OMP_CLAUSE_DEFAULT);
  OMP_CLAUSE_CHAIN (c) = list;
  OMP_CLAUSE_DEFAULT_KIND (c) = kind;

  return c;
}

/* OpenMP 2.5:
   firstprivate ( variable-list ) */

static tree
c_parser_omp_clause_firstprivate (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_FIRSTPRIVATE, list);
}

/* OpenMP 3.1:
   final ( expression ) */

static tree
c_parser_omp_clause_final (c_parser *parser, tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      matching_parens parens;
      tree t, c;
      if (!parens.require_open (parser))
        t = error_mark_node;
      else
        {
          location_t eloc = c_parser_peek_token (parser)->location;
          c_expr expr = c_parser_expr_no_commas (parser, NULL);
          t = convert_lvalue_to_rvalue (eloc, expr, true, true).value;
          t = c_objc_common_truthvalue_conversion (eloc, t);
          t = c_fully_fold (t, false, NULL);
          parens.skip_until_found_close (parser);
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_FINAL, "final");

      c = build_omp_clause (loc, OMP_CLAUSE_FINAL);
      OMP_CLAUSE_FINAL_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }
  else
    c_parser_error (parser, "expected %<(%>");

  return list;
}

/* OpenMP 5.1:
   indirect [( expression )]
*/

static tree
c_parser_omp_clause_indirect (c_parser *parser, tree list)
{
  location_t location = c_parser_peek_token (parser)->location;
  tree t;

  if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
    {
      matching_parens parens;
      if (!parens.require_open (parser))
        return list;

      location_t loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (loc, expr, true, true);
      t = c_objc_common_truthvalue_conversion (loc, expr.value);
      t = c_fully_fold (t, false, NULL);
      if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
          || TREE_CODE (t) != INTEGER_CST)
        {
          c_parser_error (parser, "expected constant logical expression");
          return list;
        }
      parens.skip_until_found_close (parser);
    }
  else
    t = integer_one_node;

  check_no_duplicate_clause (list, OMP_CLAUSE_INDIRECT, "indirect");

  tree c = build_omp_clause (location, OMP_CLAUSE_INDIRECT);
  OMP_CLAUSE_INDIRECT_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenACC, OpenMP 2.5:
   if ( expression )

   OpenMP 4.5:
   if ( directive-name-modifier : expression )

   directive-name-modifier:
     parallel | task | taskloop | target data | target | target update
     | target enter data | target exit data

   OpenMP 5.0:
   directive-name-modifier:
     ... | simd | cancel  */

static tree
c_parser_omp_clause_if (c_parser *parser, tree list, bool is_omp)
{
  location_t location = c_parser_peek_token (parser)->location;
  enum tree_code if_modifier = ERROR_MARK;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (is_omp && c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      int n = 2;
      if (strcmp (p, "cancel") == 0)
        if_modifier = VOID_CST;
      else if (strcmp (p, "parallel") == 0)
        if_modifier = OMP_PARALLEL;
      else if (strcmp (p, "simd") == 0)
        if_modifier = OMP_SIMD;
      else if (strcmp (p, "task") == 0)
        if_modifier = OMP_TASK;
      else if (strcmp (p, "taskloop") == 0)
        if_modifier = OMP_TASKLOOP;
      else if (strcmp (p, "target") == 0)
        {
          if_modifier = OMP_TARGET;
          if (c_parser_peek_2nd_token (parser)->type == CPP_NAME)
            {
              p = IDENTIFIER_POINTER (c_parser_peek_2nd_token (parser)->value);
              if (strcmp ("data", p) == 0)
                if_modifier = OMP_TARGET_DATA;
              else if (strcmp ("update", p) == 0)
                if_modifier = OMP_TARGET_UPDATE;
              else if (strcmp ("enter", p) == 0)
                if_modifier = OMP_TARGET_ENTER_DATA;
              else if (strcmp ("exit", p) == 0)
                if_modifier = OMP_TARGET_EXIT_DATA;
              if (if_modifier != OMP_TARGET)
                {
                  n = 3;
                  c_parser_consume_token (parser);
                }
              else
                {
                  location_t loc = c_parser_peek_2nd_token (parser)->location;
                  error_at (loc, "expected %<data%>, %<update%>, %<enter%> "
                                 "or %<exit%>");
                  if_modifier = ERROR_MARK;
                }
              if (if_modifier == OMP_TARGET_ENTER_DATA
                  || if_modifier == OMP_TARGET_EXIT_DATA)
                {
                  if (c_parser_peek_2nd_token (parser)->type == CPP_NAME)
                    {
                      p = IDENTIFIER_POINTER
                                (c_parser_peek_2nd_token (parser)->value);
                      if (strcmp ("data", p) == 0)
                        n = 4;
                    }
                  if (n == 4)
                    c_parser_consume_token (parser);
                  else
                    {
                      location_t loc
                        = c_parser_peek_2nd_token (parser)->location;
                      error_at (loc, "expected %<data%>");
                      if_modifier = ERROR_MARK;
                    }
                }
            }
        }
      if (if_modifier != ERROR_MARK)
        {
          if (c_parser_peek_2nd_token (parser)->type == CPP_COLON)
            {
              c_parser_consume_token (parser);
              c_parser_consume_token (parser);
            }
          else
            {
              if (n > 2)
                {
                  location_t loc = c_parser_peek_2nd_token (parser)->location;
                  error_at (loc, "expected %<:%>");
                }
              if_modifier = ERROR_MARK;
            }
        }
    }

  location_t loc = c_parser_peek_token (parser)->location;
  c_expr expr = c_parser_expr_no_commas (parser, NULL);
  expr = convert_lvalue_to_rvalue (loc, expr, true, true);
  tree t = c_objc_common_truthvalue_conversion (loc, expr.value), c;
  t = c_fully_fold (t, false, NULL);
  parens.skip_until_found_close (parser);

  for (c = list; c ; c = OMP_CLAUSE_CHAIN (c))
    if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_IF)
      {
        if (if_modifier != ERROR_MARK
            && OMP_CLAUSE_IF_MODIFIER (c) == if_modifier)
          {
            const char *p = NULL;
            switch (if_modifier)
              {
              case VOID_CST: p = "cancel"; break;
              case OMP_PARALLEL: p = "parallel"; break;
              case OMP_SIMD: p = "simd"; break;
              case OMP_TASK: p = "task"; break;
              case OMP_TASKLOOP: p = "taskloop"; break;
              case OMP_TARGET_DATA: p = "target data"; break;
              case OMP_TARGET: p = "target"; break;
              case OMP_TARGET_UPDATE: p = "target update"; break;
              case OMP_TARGET_ENTER_DATA: p = "target enter data"; break;
              case OMP_TARGET_EXIT_DATA: p = "target exit data"; break;
              default: gcc_unreachable ();
              }
            error_at (location, "too many %<if%> clauses with %qs modifier",
                      p);
            return list;
          }
        else if (OMP_CLAUSE_IF_MODIFIER (c) == if_modifier)
          {
            if (!is_omp)
              error_at (location, "too many %<if%> clauses");
            else
              error_at (location, "too many %<if%> clauses without modifier");
            return list;
          }
        else if (if_modifier == ERROR_MARK
                 || OMP_CLAUSE_IF_MODIFIER (c) == ERROR_MARK)
          {
            error_at (location, "if any %<if%> clause has modifier, then all "
                                "%<if%> clauses have to use modifier");
            return list;
          }
      }

  c = build_omp_clause (location, OMP_CLAUSE_IF);
  OMP_CLAUSE_IF_MODIFIER (c) = if_modifier;
  OMP_CLAUSE_IF_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 2.5:
   lastprivate ( variable-list )

   OpenMP 5.0:
   lastprivate ( [ lastprivate-modifier : ] variable-list ) */

static tree
c_parser_omp_clause_lastprivate (c_parser *parser, tree list)
{
  /* The clauses location.  */
  location_t loc = c_parser_peek_token (parser)->location;

  if (c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
    {
      bool conditional = false;
      if (c_parser_next_token_is (parser, CPP_NAME)
          && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
        {
          const char *p
            = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
          if (strcmp (p, "conditional") == 0)
            {
              conditional = true;
              c_parser_consume_token (parser);
              c_parser_consume_token (parser);
            }
        }
      tree nlist = c_parser_omp_variable_list (parser, loc,
                                               OMP_CLAUSE_LASTPRIVATE, list);
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, "expected %<)%>");
      if (conditional)
        for (tree c = nlist; c != list; c = OMP_CLAUSE_CHAIN (c))
          OMP_CLAUSE_LASTPRIVATE_CONDITIONAL (c) = 1;
      return nlist;
    }
  return list;
}

/* OpenMP 3.1:
   mergeable */

static tree
c_parser_omp_clause_mergeable (c_parser *parser ATTRIBUTE_UNUSED, tree list)
{
  tree c;

  /* FIXME: Should we allow duplicates?  */
  check_no_duplicate_clause (list, OMP_CLAUSE_MERGEABLE, "mergeable");

  c = build_omp_clause (c_parser_peek_token (parser)->location,
                        OMP_CLAUSE_MERGEABLE);
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenMP 2.5:
   nowait */

static tree
c_parser_omp_clause_nowait (c_parser *parser ATTRIBUTE_UNUSED, tree list)
{
  tree c;
  location_t loc = c_parser_peek_token (parser)->location;

  check_no_duplicate_clause (list, OMP_CLAUSE_NOWAIT, "nowait");

  c = build_omp_clause (loc, OMP_CLAUSE_NOWAIT);
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 2.5:
   num_threads ( expression ) */

static tree
c_parser_omp_clause_num_threads (c_parser *parser, tree list)
{
  location_t num_threads_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't positive.  */
      c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, t,
                       build_int_cst (TREE_TYPE (t), 0));
      protected_set_expr_location (c, expr_loc);
      if (c == boolean_true_node)
        {
          warning_at (expr_loc, OPT_Wopenmp,
                      "%<num_threads%> value must be positive");
          t = integer_one_node;
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_NUM_THREADS, "num_threads");

      c = build_omp_clause (num_threads_loc, OMP_CLAUSE_NUM_THREADS);
      OMP_CLAUSE_NUM_THREADS_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.5:
   num_tasks ( expression )

   OpenMP 5.1:
   num_tasks ( strict : expression ) */

static tree
c_parser_omp_clause_num_tasks (c_parser *parser, tree list)
{
  location_t num_tasks_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      bool strict = false;
      if (c_parser_next_token_is (parser, CPP_NAME)
          && c_parser_peek_2nd_token (parser)->type == CPP_COLON
          && strcmp (IDENTIFIER_POINTER (c_parser_peek_token (parser)->value),
                     "strict") == 0)
        {
          strict = true;
          c_parser_consume_token (parser);
          c_parser_consume_token (parser);
        }

      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't positive.  */
      c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, t,
                           build_int_cst (TREE_TYPE (t), 0));
      if (CAN_HAVE_LOCATION_P (c))
        SET_EXPR_LOCATION (c, expr_loc);
      if (c == boolean_true_node)
        {
          warning_at (expr_loc, OPT_Wopenmp,
                      "%<num_tasks%> value must be positive");
          t = integer_one_node;
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_NUM_TASKS, "num_tasks");

      c = build_omp_clause (num_tasks_loc, OMP_CLAUSE_NUM_TASKS);
      OMP_CLAUSE_NUM_TASKS_EXPR (c) = t;
      OMP_CLAUSE_NUM_TASKS_STRICT (c) = strict;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.5:
   grainsize ( expression )

   OpenMP 5.1:
   grainsize ( strict : expression ) */

static tree
c_parser_omp_clause_grainsize (c_parser *parser, tree list)
{
  location_t grainsize_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      bool strict = false;
      if (c_parser_next_token_is (parser, CPP_NAME)
          && c_parser_peek_2nd_token (parser)->type == CPP_COLON
          && strcmp (IDENTIFIER_POINTER (c_parser_peek_token (parser)->value),
                     "strict") == 0)
        {
          strict = true;
          c_parser_consume_token (parser);
          c_parser_consume_token (parser);
        }

      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't positive.  */
      c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, t,
                           build_int_cst (TREE_TYPE (t), 0));
      if (CAN_HAVE_LOCATION_P (c))
        SET_EXPR_LOCATION (c, expr_loc);
      if (c == boolean_true_node)
        {
          warning_at (expr_loc, OPT_Wopenmp,
                      "%<grainsize%> value must be positive");
          t = integer_one_node;
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_GRAINSIZE, "grainsize");

      c = build_omp_clause (grainsize_loc, OMP_CLAUSE_GRAINSIZE);
      OMP_CLAUSE_GRAINSIZE_EXPR (c) = t;
      OMP_CLAUSE_GRAINSIZE_STRICT (c) = strict;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.5:
   priority ( expression ) */

static tree
c_parser_omp_clause_priority (c_parser *parser, tree list)
{
  location_t priority_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't
         non-negative.  */
      c = fold_build2_loc (expr_loc, LT_EXPR, boolean_type_node, t,
                           build_int_cst (TREE_TYPE (t), 0));
      if (CAN_HAVE_LOCATION_P (c))
        SET_EXPR_LOCATION (c, expr_loc);
      if (c == boolean_true_node)
        {
          warning_at (expr_loc, OPT_Wopenmp,
                      "%<priority%> value must be non-negative");
          t = integer_one_node;
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_PRIORITY, "priority");

      c = build_omp_clause (priority_loc, OMP_CLAUSE_PRIORITY);
      OMP_CLAUSE_PRIORITY_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.5:
   hint ( expression ) */

static tree
c_parser_omp_clause_hint (c_parser *parser, tree list)
{
  location_t hint_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);
      if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
          || TREE_CODE (t) != INTEGER_CST
          || tree_int_cst_sgn (t) == -1)
        {
          c_parser_error (parser, "expected constant integer expression "
                                  "with valid sync-hint value");
          return list;
        }
      parens.skip_until_found_close (parser);
      check_no_duplicate_clause (list, OMP_CLAUSE_HINT, "hint");

      c = build_omp_clause (hint_loc, OMP_CLAUSE_HINT);
      OMP_CLAUSE_HINT_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 5.1:
   filter ( integer-expression ) */

static tree
c_parser_omp_clause_filter (c_parser *parser, tree list)
{
  location_t hint_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);
      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }
      parens.skip_until_found_close (parser);
      check_no_duplicate_clause (list, OMP_CLAUSE_FILTER, "filter");

      c = build_omp_clause (hint_loc, OMP_CLAUSE_FILTER);
      OMP_CLAUSE_FILTER_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.5:
   defaultmap ( tofrom : scalar )

   OpenMP 5.0:
   defaultmap ( implicit-behavior [ : variable-category ] ) */

static tree
c_parser_omp_clause_defaultmap (c_parser *parser, tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree c;
  const char *p;
  enum omp_clause_defaultmap_kind behavior = OMP_CLAUSE_DEFAULTMAP_DEFAULT;
  enum omp_clause_defaultmap_kind category
    = OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;
  if (c_parser_next_token_is_keyword (parser, RID_DEFAULT))
    p = "default";
  else if (!c_parser_next_token_is (parser, CPP_NAME))
    {
    invalid_behavior:
      c_parser_error (parser, "expected %<alloc%>, %<to%>, %<from%>, "
                              "%<tofrom%>, %<firstprivate%>, %<none%> "
                              "or %<default%>");
      goto out_err;
    }
  else
    p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

  switch (p[0])
    {
    case 'a':
      if (strcmp ("alloc", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_ALLOC;
      else
        goto invalid_behavior;
      break;

    case 'd':
      if (strcmp ("default", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_DEFAULT;
      else
        goto invalid_behavior;
      break;

    case 'f':
      if (strcmp ("firstprivate", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_FIRSTPRIVATE;
      else if (strcmp ("from", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_FROM;
      else
        goto invalid_behavior;
      break;

    case 'n':
      if (strcmp ("none", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_NONE;
      else
        goto invalid_behavior;
      break;

    case 'p':
      if (strcmp ("present", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_PRESENT;
      else
        goto invalid_behavior;
      break;

    case 't':
      if (strcmp ("tofrom", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_TOFROM;
      else if (strcmp ("to", p) == 0)
        behavior = OMP_CLAUSE_DEFAULTMAP_TO;
      else
        goto invalid_behavior;
      break;

    default:
      goto invalid_behavior;
    }
  c_parser_consume_token (parser);

  if (!c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
    {
      if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        goto out_err;
      if (!c_parser_next_token_is (parser, CPP_NAME))
        {
        invalid_category:
          c_parser_error (parser, "expected %<scalar%>, %<aggregate%>, "
                                  "%<pointer%> or %<all%>");
          goto out_err;
        }
      p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      switch (p[0])
        {
        case 'a':
          if (strcmp ("aggregate", p) == 0)
            category = OMP_CLAUSE_DEFAULTMAP_CATEGORY_AGGREGATE;
          else if (strcmp ("all", p) == 0)
            category = OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL;
          else
            goto invalid_category;
          break;

        case 'p':
          if (strcmp ("pointer", p) == 0)
            category = OMP_CLAUSE_DEFAULTMAP_CATEGORY_POINTER;
          else
            goto invalid_category;
          break;

        case 's':
          if (strcmp ("scalar", p) == 0)
            category = OMP_CLAUSE_DEFAULTMAP_CATEGORY_SCALAR;
          else
            goto invalid_category;
          break;

        default:
          goto invalid_category;
        }

      c_parser_consume_token (parser);
    }
  parens.skip_until_found_close (parser);

  for (c = list; c ; c = OMP_CLAUSE_CHAIN (c))
    if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEFAULTMAP
        && (category == OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED
            || category == OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL
            || OMP_CLAUSE_DEFAULTMAP_CATEGORY (c) == category
            || (OMP_CLAUSE_DEFAULTMAP_CATEGORY (c)
                == OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED)
            || (OMP_CLAUSE_DEFAULTMAP_CATEGORY (c)
                == OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL)))
      {
        enum omp_clause_defaultmap_kind cat = category;
        location_t loc = OMP_CLAUSE_LOCATION (c);
        if (cat == OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED
            || (cat == OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL
                && (OMP_CLAUSE_DEFAULTMAP_CATEGORY (c)
                    != OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED)))
          cat = OMP_CLAUSE_DEFAULTMAP_CATEGORY (c);
        p = NULL;
        switch (cat)
          {
          case OMP_CLAUSE_DEFAULTMAP_CATEGORY_UNSPECIFIED:
            p = NULL;
            break;
          case OMP_CLAUSE_DEFAULTMAP_CATEGORY_ALL:
            p = "all";
            break;
          case OMP_CLAUSE_DEFAULTMAP_CATEGORY_AGGREGATE:
            p = "aggregate";
            break;
          case OMP_CLAUSE_DEFAULTMAP_CATEGORY_POINTER:
            p = "pointer";
            break;
          case OMP_CLAUSE_DEFAULTMAP_CATEGORY_SCALAR:
            p = "scalar";
            break;
          default:
            gcc_unreachable ();
          }
        if (p)
          error_at (loc, "too many %<defaultmap%> clauses with %qs category",
                    p);
        else
          error_at (loc, "too many %<defaultmap%> clauses with unspecified "
                         "category");
        break;
      }

  c = build_omp_clause (loc, OMP_CLAUSE_DEFAULTMAP);
  OMP_CLAUSE_DEFAULTMAP_SET_KIND (c, behavior, category);
  OMP_CLAUSE_CHAIN (c) = list;
  return c;

 out_err:
  parens.skip_until_found_close (parser);
  return list;
}

/* OpenACC 2.0:
   use_device ( variable-list )

   OpenMP 4.5:
   use_device_ptr ( variable-list ) */

static tree
c_parser_omp_clause_use_device_ptr (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_USE_DEVICE_PTR,
                                       list);
}

/* OpenMP 5.0:
   use_device_addr ( variable-list ) */

static tree
c_parser_omp_clause_use_device_addr (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_USE_DEVICE_ADDR,
                                       list);
}

/* OpenMP 5.1:
   has_device_addr ( variable-list ) */

static tree
c_parser_omp_clause_has_device_addr (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_HAS_DEVICE_ADDR,
                                       list);
}

/* OpenMP 4.5:
   is_device_ptr ( variable-list ) */

static tree
c_parser_omp_clause_is_device_ptr (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_IS_DEVICE_PTR, list);
}

/* OpenACC:
   num_gangs ( expression )
   num_workers ( expression )
   vector_length ( expression )  */

static tree
c_parser_oacc_single_int_clause (c_parser *parser, omp_clause_code code,
                                 tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  location_t expr_loc = c_parser_peek_token (parser)->location;
  c_expr expr = c_parser_expression (parser);
  expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
  tree c, t = expr.value;
  t = c_fully_fold (t, false, NULL);

  parens.skip_until_found_close (parser);

  if (t == error_mark_node)
    return list;
  else if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
    {
      error_at (expr_loc, "%qs expression must be integral",
                omp_clause_code_name[code]);
      return list;
    }

  /* Attempt to statically determine when the number isn't positive.  */
  c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, t,
                       build_int_cst (TREE_TYPE (t), 0));
  protected_set_expr_location (c, expr_loc);
  if (c == boolean_true_node)
    {
      warning_at (expr_loc, 0,
                  "%qs value must be positive",
                  omp_clause_code_name[code]);
      t = integer_one_node;
    }

  check_no_duplicate_clause (list, code, omp_clause_code_name[code]);

  c = build_omp_clause (loc, code);
  OMP_CLAUSE_OPERAND (c, 0) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenACC:

    gang [( gang-arg-list )]
    worker [( [num:] int-expr )]
    vector [( [length:] int-expr )]

  where gang-arg is one of:

    [num:] int-expr
    static: size-expr

  and size-expr may be:

    *
    int-expr
*/

static tree
c_parser_oacc_shape_clause (c_parser *parser, location_t loc,
                            omp_clause_code kind,
                            const char *str, tree list)
{
  const char *id = "num";
  tree ops[2] = { NULL_TREE, NULL_TREE }, c;

  if (kind == OMP_CLAUSE_VECTOR)
    id = "length";

  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      c_parser_consume_token (parser);

      do
        {
          c_token *next = c_parser_peek_token (parser);
          int idx = 0;

          /* Gang static argument.  */
          if (kind == OMP_CLAUSE_GANG
              && c_parser_next_token_is_keyword (parser, RID_STATIC))
            {
              c_parser_consume_token (parser);

              if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
                goto cleanup_error;

              idx = 1;
              if (ops[idx] != NULL_TREE)
                {
                  c_parser_error (parser, "too many %<static%> arguments");
                  goto cleanup_error;
                }

              /* Check for the '*' argument.  */
              if (c_parser_next_token_is (parser, CPP_MULT)
                  && (c_parser_peek_2nd_token (parser)->type == CPP_COMMA
                      || c_parser_peek_2nd_token (parser)->type
                         == CPP_CLOSE_PAREN))
                {
                  c_parser_consume_token (parser);
                  ops[idx] = integer_minus_one_node;

                  if (c_parser_next_token_is (parser, CPP_COMMA))
                    {
                      c_parser_consume_token (parser);
                      continue;
                    }
                  else
                    break;
                }
            }
          /* Worker num: argument and vector length: arguments.  */
          else if (c_parser_next_token_is (parser, CPP_NAME)
                   && strcmp (id, IDENTIFIER_POINTER (next->value)) == 0
                   && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
            {
              c_parser_consume_token (parser);  /* id  */
              c_parser_consume_token (parser);  /* ':'  */
            }

          /* Now collect the actual argument.  */
          if (ops[idx] != NULL_TREE)
            {
              c_parser_error (parser, "unexpected argument");
              goto cleanup_error;
            }

          location_t expr_loc = c_parser_peek_token (parser)->location;
          c_expr cexpr = c_parser_expr_no_commas (parser, NULL);
          cexpr = convert_lvalue_to_rvalue (expr_loc, cexpr, false, true);
          tree expr = cexpr.value;
          if (expr == error_mark_node)
            goto cleanup_error;

          expr = c_fully_fold (expr, false, NULL);

          /* Attempt to statically determine when the number isn't a
             positive integer.  */

          if (!INTEGRAL_TYPE_P (TREE_TYPE (expr)))
            {
              c_parser_error (parser, "expected integer expression");
              return list;
            }

          tree c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, expr,
                                    build_int_cst (TREE_TYPE (expr), 0));
          if (c == boolean_true_node)
            {
              warning_at (loc, 0,
                          "%qs value must be positive", str);
              expr = integer_one_node;
            }

          ops[idx] = expr;

          if (kind == OMP_CLAUSE_GANG
              && c_parser_next_token_is (parser, CPP_COMMA))
            {
              c_parser_consume_token (parser);
              continue;
            }
          break;
        }
      while (1);

      if (!c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
        goto cleanup_error;
    }

  check_no_duplicate_clause (list, kind, str);

  c = build_omp_clause (loc, kind);

  if (ops[1])
    OMP_CLAUSE_OPERAND (c, 1) = ops[1];

  OMP_CLAUSE_OPERAND (c, 0) = ops[0];
  OMP_CLAUSE_CHAIN (c) = list;

  return c;

 cleanup_error:
  c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, 0);
  return list;
}

/* OpenACC 2.5:
   auto
   finalize
   independent
   nohost
   seq */

static tree
c_parser_oacc_simple_clause (location_t loc, enum omp_clause_code code,
                             tree list)
{
  check_no_duplicate_clause (list, code, omp_clause_code_name[code]);

  tree c = build_omp_clause (loc, code);
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenACC:
   async [( int-expr )] */

static tree
c_parser_oacc_clause_async (c_parser *parser, tree list)
{
  tree c, t;
  location_t loc = c_parser_peek_token (parser)->location;

  t = build_int_cst (integer_type_node, GOMP_ASYNC_NOVAL);

  if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
    {
      c_parser_consume_token (parser);

      t = c_parser_expr_no_commas (parser, NULL).value;
      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        c_parser_error (parser, "expected integer expression");
      else if (t == error_mark_node
          || !c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
        return list;
    }
  else
    t = c_fully_fold (t, false, NULL);

  check_no_duplicate_clause (list, OMP_CLAUSE_ASYNC, "async");

  c = build_omp_clause (loc, OMP_CLAUSE_ASYNC);
  OMP_CLAUSE_ASYNC_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  list = c;

  return list;
}

/* OpenACC 2.0:
   tile ( size-expr-list ) */

static tree
c_parser_oacc_clause_tile (c_parser *parser, tree list)
{
  tree c, expr = error_mark_node;
  location_t loc;
  tree tile = NULL_TREE;

  check_no_duplicate_clause (list, OMP_CLAUSE_TILE, "tile");
  check_no_duplicate_clause (list, OMP_CLAUSE_COLLAPSE, "collapse");

  loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
    return list;

  do
    {
      if (tile && !c_parser_require (parser, CPP_COMMA, "expected %<,%>"))
        return list;

      if (c_parser_next_token_is (parser, CPP_MULT)
          && (c_parser_peek_2nd_token (parser)->type == CPP_COMMA
              || c_parser_peek_2nd_token (parser)->type == CPP_CLOSE_PAREN))
        {
          c_parser_consume_token (parser);
          expr = integer_zero_node;
        }
      else
        {
          location_t expr_loc = c_parser_peek_token (parser)->location;
          c_expr cexpr = c_parser_expr_no_commas (parser, NULL);
          cexpr = convert_lvalue_to_rvalue (expr_loc, cexpr, false, true);
          expr = cexpr.value;

          if (expr == error_mark_node)
            {
              c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                         "expected %<)%>");
              return list;
            }

          expr = c_fully_fold (expr, false, NULL);

          if (!INTEGRAL_TYPE_P (TREE_TYPE (expr))
              || !tree_fits_shwi_p (expr)
              || tree_to_shwi (expr) <= 0)
            {
              error_at (expr_loc, "%<tile%> argument needs positive"
                        " integral constant");
              expr = integer_zero_node;
            }
        }

      tile = tree_cons (NULL_TREE, expr, tile);
    }
  while (c_parser_next_token_is_not (parser, CPP_CLOSE_PAREN));

  /* Consume the trailing ')'.  */
  c_parser_consume_token (parser);

  c = build_omp_clause (loc, OMP_CLAUSE_TILE);
  tile = nreverse (tile);
  OMP_CLAUSE_TILE_LIST (c) = tile;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenACC:
   wait [( int-expr-list )] */

static tree
c_parser_oacc_clause_wait (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;

  if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
    list = c_parser_oacc_wait_list (parser, clause_loc, list);
  else
    {
      tree c = build_omp_clause (clause_loc, OMP_CLAUSE_WAIT);

      OMP_CLAUSE_DECL (c) = build_int_cst (integer_type_node, GOMP_ASYNC_NOVAL);
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenACC 2.7:
   self [( expression )] */

static tree
c_parser_oacc_compute_clause_self (c_parser *parser, tree list)
{
  tree t;
  location_t location = c_parser_peek_token (parser)->location;
  if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
    {
      matching_parens parens;
      parens.consume_open (parser);

      location_t loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (loc, expr, true, true);
      t = c_objc_common_truthvalue_conversion (loc, expr.value);
      t = c_fully_fold (t, false, NULL);
      parens.skip_until_found_close (parser);
    }
  else
    t = truthvalue_true_node;

  for (tree c = list; c; c = OMP_CLAUSE_CHAIN (c))
    if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_SELF)
      {
        error_at (location, "too many %<self%> clauses");
        return list;
      }

  tree c = build_omp_clause (location, OMP_CLAUSE_SELF);
  OMP_CLAUSE_SELF_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 5.0:
   order ( concurrent )

   OpenMP 5.1:
   order ( order-modifier : concurrent )

   order-modifier:
     reproducible
     unconstrained  */

static tree
c_parser_omp_clause_order (c_parser *parser, tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree c;
  const char *p;
  bool unconstrained = false;
  bool reproducible = false;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;
  if (c_parser_next_token_is (parser, CPP_NAME)
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    {
      p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "unconstrained") == 0)
        unconstrained = true;
      else if (strcmp (p, "reproducible") == 0)
        reproducible = true;
      else
        {
          c_parser_error (parser, "expected %<reproducible%> or "
                                  "%<unconstrained%>");
          goto out_err;
        }
      c_parser_consume_token (parser);
      c_parser_consume_token (parser);
    }
  if (!c_parser_next_token_is (parser, CPP_NAME))
    {
      c_parser_error (parser, "expected %<concurrent%>");
      goto out_err;
    }
  p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp (p, "concurrent") != 0)
    {
      c_parser_error (parser, "expected %<concurrent%>");
      goto out_err;
    }
  c_parser_consume_token (parser);
  parens.skip_until_found_close (parser);
  check_no_duplicate_clause (list, OMP_CLAUSE_ORDER, "order");
  c = build_omp_clause (loc, OMP_CLAUSE_ORDER);
  OMP_CLAUSE_ORDER_UNCONSTRAINED (c) = unconstrained;
  OMP_CLAUSE_ORDER_REPRODUCIBLE (c) = reproducible;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;

 out_err:
  parens.skip_until_found_close (parser);
  return list;
}


/* OpenMP 5.0:
   bind ( teams | parallel | thread ) */

static tree
c_parser_omp_clause_bind (c_parser *parser, tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree c;
  const char *p;
  enum omp_clause_bind_kind kind = OMP_CLAUSE_BIND_THREAD;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;
  if (!c_parser_next_token_is (parser, CPP_NAME))
    {
     invalid:
      c_parser_error (parser,
                      "expected %<teams%>, %<parallel%> or %<thread%>");
      parens.skip_until_found_close (parser);
      return list;
    }
  p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp (p, "teams") == 0)
    kind = OMP_CLAUSE_BIND_TEAMS;
  else if (strcmp (p, "parallel") == 0)
    kind = OMP_CLAUSE_BIND_PARALLEL;
  else if (strcmp (p, "thread") != 0)
    goto invalid;
  c_parser_consume_token (parser);
  parens.skip_until_found_close (parser);
  /* check_no_duplicate_clause (list, OMP_CLAUSE_BIND, "bind"); */
  c = build_omp_clause (loc, OMP_CLAUSE_BIND);
  OMP_CLAUSE_BIND_KIND (c) = kind;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}


/* OpenMP 2.5:
   ordered

   OpenMP 4.5:
   ordered ( constant-expression ) */

static tree
c_parser_omp_clause_ordered (c_parser *parser, tree list)
{
  check_no_duplicate_clause (list, OMP_CLAUSE_ORDERED, "ordered");

  tree c, num = NULL_TREE;
  HOST_WIDE_INT n;
  location_t loc = c_parser_peek_token (parser)->location;
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      matching_parens parens;
      parens.consume_open (parser);
      num = c_parser_expr_no_commas (parser, NULL).value;
      parens.skip_until_found_close (parser);
    }
  if (num == error_mark_node)
    return list;
  if (num)
    {
      mark_exp_read (num);
      num = c_fully_fold (num, false, NULL);
      if (!INTEGRAL_TYPE_P (TREE_TYPE (num))
          || !tree_fits_shwi_p (num)
          || (n = tree_to_shwi (num)) <= 0
          || (int) n != n)
        {
          error_at (loc, "ordered argument needs positive "
                         "constant integer expression");
          return list;
        }
    }
  c = build_omp_clause (loc, OMP_CLAUSE_ORDERED);
  OMP_CLAUSE_ORDERED_EXPR (c) = num;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 2.5:
   private ( variable-list ) */

static tree
c_parser_omp_clause_private (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_PRIVATE, list);
}

/* OpenMP 2.5:
   reduction ( reduction-operator : variable-list )

   reduction-operator:
     One of: + * - & ^ | && ||

   OpenMP 3.1:
   
   reduction-operator:
     One of: + * - & ^ | && || max min

   OpenMP 4.0:

   reduction-operator:
     One of: + * - & ^ | && ||
     identifier

   OpenMP 5.0:
   reduction ( reduction-modifier, reduction-operator : variable-list )
   in_reduction ( reduction-operator : variable-list )
   task_reduction ( reduction-operator : variable-list )  */

static tree
c_parser_omp_clause_reduction (c_parser *parser, enum omp_clause_code kind,
                               bool is_omp, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      bool task = false;
      bool inscan = false;
      enum tree_code code = ERROR_MARK;
      tree reduc_id = NULL_TREE;

      if (kind == OMP_CLAUSE_REDUCTION && is_omp)
        {
          if (c_parser_next_token_is_keyword (parser, RID_DEFAULT)
              && c_parser_peek_2nd_token (parser)->type == CPP_COMMA)
            {
              c_parser_consume_token (parser);
              c_parser_consume_token (parser);
            }
          else if (c_parser_next_token_is (parser, CPP_NAME)
                   && c_parser_peek_2nd_token (parser)->type == CPP_COMMA)
            {
              const char *p
                = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
              if (strcmp (p, "task") == 0)
                task = true;
              else if (strcmp (p, "inscan") == 0)
                inscan = true;
              if (task || inscan)
                {
                  c_parser_consume_token (parser);
                  c_parser_consume_token (parser);
                }
            }
        }

      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_PLUS:
          code = PLUS_EXPR;
          break;
        case CPP_MULT:
          code = MULT_EXPR;
          break;
        case CPP_MINUS:
          code = MINUS_EXPR;
          break;
        case CPP_AND:
          code = BIT_AND_EXPR;
          break;
        case CPP_XOR:
          code = BIT_XOR_EXPR;
          break;
        case CPP_OR:
          code = BIT_IOR_EXPR;
          break;
        case CPP_AND_AND:
          code = TRUTH_ANDIF_EXPR;
          break;
        case CPP_OR_OR:
          code = TRUTH_ORIF_EXPR;
          break;
        case CPP_NAME:
          {
            const char *p
              = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
            if (strcmp (p, "min") == 0)
              {
                code = MIN_EXPR;
                break;
              }
            if (strcmp (p, "max") == 0)
              {
                code = MAX_EXPR;
                break;
              }
            reduc_id = c_parser_peek_token (parser)->value;
            break;
          }
        default:
          c_parser_error (parser,
                          "expected %<+%>, %<*%>, %<-%>, %<&%>, "
                          "%<^%>, %<|%>, %<&&%>, %<||%> or identifier");
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, 0);
          return list;
        }
      c_parser_consume_token (parser);
      reduc_id = c_omp_reduction_id (code, reduc_id);
      if (c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        {
          tree nl, c;

          nl = c_parser_omp_variable_list (parser, clause_loc, kind, list);
          for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
            {
              tree d = OMP_CLAUSE_DECL (c), type;
              if (TREE_CODE (d) != OMP_ARRAY_SECTION)
                type = TREE_TYPE (d);
              else
                {
                  int cnt = 0;
                  tree t;
                  for (t = d;
                      TREE_CODE (t) == OMP_ARRAY_SECTION;
                      t = TREE_OPERAND (t, 0))
                    cnt++;
                  type = TREE_TYPE (t);
                  while (cnt > 0)
                    {
                      if (TREE_CODE (type) != POINTER_TYPE
                          && TREE_CODE (type) != ARRAY_TYPE)
                        break;
                      type = TREE_TYPE (type);
                      cnt--;
                    }
                }
              while (TREE_CODE (type) == ARRAY_TYPE)
                type = TREE_TYPE (type);
              OMP_CLAUSE_REDUCTION_CODE (c) = code;
              if (task)
                OMP_CLAUSE_REDUCTION_TASK (c) = 1;
              else if (inscan)
                OMP_CLAUSE_REDUCTION_INSCAN (c) = 1;
              if (code == ERROR_MARK
                  || !(INTEGRAL_TYPE_P (type)
                       || SCALAR_FLOAT_TYPE_P (type)
                       || TREE_CODE (type) == COMPLEX_TYPE))
                OMP_CLAUSE_REDUCTION_PLACEHOLDER (c)
                  = c_omp_reduction_lookup (reduc_id,
                                            TYPE_MAIN_VARIANT (type));
            }

          list = nl;
        }
      parens.skip_until_found_close (parser);
    }
  return list;
}

/* OpenMP 2.5:
   schedule ( schedule-kind )
   schedule ( schedule-kind , expression )

   schedule-kind:
     static | dynamic | guided | runtime | auto

   OpenMP 4.5:
   schedule ( schedule-modifier : schedule-kind )
   schedule ( schedule-modifier [ , schedule-modifier ] : schedule-kind , expression )

   schedule-modifier:
     simd
     monotonic
     nonmonotonic  */

static tree
c_parser_omp_clause_schedule (c_parser *parser, tree list)
{
  tree c, t;
  location_t loc = c_parser_peek_token (parser)->location;
  int modifiers = 0, nmodifiers = 0;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  c = build_omp_clause (loc, OMP_CLAUSE_SCHEDULE);

  location_t comma = UNKNOWN_LOCATION;
  while (c_parser_next_token_is (parser, CPP_NAME))
    {
      tree kind = c_parser_peek_token (parser)->value;
      const char *p = IDENTIFIER_POINTER (kind);
      if (strcmp ("simd", p) == 0)
        OMP_CLAUSE_SCHEDULE_SIMD (c) = 1;
      else if (strcmp ("monotonic", p) == 0)
        modifiers |= OMP_CLAUSE_SCHEDULE_MONOTONIC;
      else if (strcmp ("nonmonotonic", p) == 0)
        modifiers |= OMP_CLAUSE_SCHEDULE_NONMONOTONIC;
      else
        break;
      comma = UNKNOWN_LOCATION;
      c_parser_consume_token (parser);
      if (nmodifiers++ == 0
          && c_parser_next_token_is (parser, CPP_COMMA))
        {
          comma = c_parser_peek_token (parser)->location;
          c_parser_consume_token (parser);
        }
      else
        {
          c_parser_require (parser, CPP_COLON, "expected %<:%>");
          break;
        }
    }
  if (comma != UNKNOWN_LOCATION)
    error_at (comma, "expected %<:%>");

  if ((modifiers & (OMP_CLAUSE_SCHEDULE_MONOTONIC
                    | OMP_CLAUSE_SCHEDULE_NONMONOTONIC))
      == (OMP_CLAUSE_SCHEDULE_MONOTONIC
          | OMP_CLAUSE_SCHEDULE_NONMONOTONIC))
    {
      error_at (loc, "both %<monotonic%> and %<nonmonotonic%> modifiers "
                     "specified");
      modifiers = 0;
    }

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      tree kind = c_parser_peek_token (parser)->value;
      const char *p = IDENTIFIER_POINTER (kind);

      switch (p[0])
        {
        case 'd':
          if (strcmp ("dynamic", p) != 0)
            goto invalid_kind;
          OMP_CLAUSE_SCHEDULE_KIND (c) = OMP_CLAUSE_SCHEDULE_DYNAMIC;
          break;

        case 'g':
          if (strcmp ("guided", p) != 0)
            goto invalid_kind;
          OMP_CLAUSE_SCHEDULE_KIND (c) = OMP_CLAUSE_SCHEDULE_GUIDED;
          break;

        case 'r':
          if (strcmp ("runtime", p) != 0)
            goto invalid_kind;
          OMP_CLAUSE_SCHEDULE_KIND (c) = OMP_CLAUSE_SCHEDULE_RUNTIME;
          break;

        default:
          goto invalid_kind;
        }
    }
  else if (c_parser_next_token_is_keyword (parser, RID_STATIC))
    OMP_CLAUSE_SCHEDULE_KIND (c) = OMP_CLAUSE_SCHEDULE_STATIC;
  else if (c_parser_next_token_is_keyword (parser, RID_AUTO))
    OMP_CLAUSE_SCHEDULE_KIND (c) = OMP_CLAUSE_SCHEDULE_AUTO;
  else
    goto invalid_kind;

  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_COMMA))
    {
      location_t here;
      c_parser_consume_token (parser);

      here = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (here, expr, false, true);
      t = expr.value;
      t = c_fully_fold (t, false, NULL);

      if (OMP_CLAUSE_SCHEDULE_KIND (c) == OMP_CLAUSE_SCHEDULE_RUNTIME)
        error_at (here, "schedule %<runtime%> does not take "
                  "a %<chunk_size%> parameter");
      else if (OMP_CLAUSE_SCHEDULE_KIND (c) == OMP_CLAUSE_SCHEDULE_AUTO)
        error_at (here,
                  "schedule %<auto%> does not take "
                  "a %<chunk_size%> parameter");
      else if (TREE_CODE (TREE_TYPE (t)) == INTEGER_TYPE
               || TREE_CODE (TREE_TYPE (t)) == BITINT_TYPE)
        {
          /* Attempt to statically determine when the number isn't
             positive.  */
          tree s = fold_build2_loc (loc, LE_EXPR, boolean_type_node, t,
                                    build_int_cst (TREE_TYPE (t), 0));
          protected_set_expr_location (s, loc);
          if (s == boolean_true_node)
            {
              warning_at (loc, OPT_Wopenmp,
                          "chunk size value must be positive");
              t = integer_one_node;
            }
          OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t;
        }
      else
        c_parser_error (parser, "expected integer expression");

      parens.skip_until_found_close (parser);
    }
  else
    c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                               "expected %<,%> or %<)%>");

  OMP_CLAUSE_SCHEDULE_KIND (c)
    = (enum omp_clause_schedule_kind)
      (OMP_CLAUSE_SCHEDULE_KIND (c) | modifiers);

  check_no_duplicate_clause (list, OMP_CLAUSE_SCHEDULE, "schedule");
  OMP_CLAUSE_CHAIN (c) = list;
  return c;

 invalid_kind:
  c_parser_error (parser, "invalid schedule kind");
  c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, 0);
  return list;
}

/* OpenMP 2.5:
   shared ( variable-list ) */

static tree
c_parser_omp_clause_shared (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_SHARED, list);
}

/* OpenMP 3.0:
   untied */

static tree
c_parser_omp_clause_untied (c_parser *parser ATTRIBUTE_UNUSED, tree list)
{
  tree c;

  /* FIXME: Should we allow duplicates?  */
  check_no_duplicate_clause (list, OMP_CLAUSE_UNTIED, "untied");

  c = build_omp_clause (c_parser_peek_token (parser)->location,
                        OMP_CLAUSE_UNTIED);
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenMP 4.0:
   inbranch
   notinbranch */

static tree
c_parser_omp_clause_branch (c_parser *parser ATTRIBUTE_UNUSED,
                            enum omp_clause_code code, tree list)
{
  check_no_duplicate_clause (list, code, omp_clause_code_name[code]);

  tree c = build_omp_clause (c_parser_peek_token (parser)->location, code);
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenMP 4.0:
   parallel
   for
   sections
   taskgroup */

static tree
c_parser_omp_clause_cancelkind (c_parser *parser ATTRIBUTE_UNUSED,
                                enum omp_clause_code code, tree list)
{
  tree c = build_omp_clause (c_parser_peek_token (parser)->location, code);
  OMP_CLAUSE_CHAIN (c) = list;

  return c;
}

/* OpenMP 4.5:
   nogroup */

static tree
c_parser_omp_clause_nogroup (c_parser *parser ATTRIBUTE_UNUSED, tree list)
{
  check_no_duplicate_clause (list, OMP_CLAUSE_NOGROUP, "nogroup");
  tree c = build_omp_clause (c_parser_peek_token (parser)->location,
                             OMP_CLAUSE_NOGROUP);
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 4.5:
   simd
   threads */

static tree
c_parser_omp_clause_orderedkind (c_parser *parser ATTRIBUTE_UNUSED,
                                 enum omp_clause_code code, tree list)
{
  check_no_duplicate_clause (list, code, omp_clause_code_name[code]);
  tree c = build_omp_clause (c_parser_peek_token (parser)->location, code);
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 4.0:
   num_teams ( expression )

   OpenMP 5.1:
   num_teams ( expression : expression ) */

static tree
c_parser_omp_clause_num_teams (c_parser *parser, tree list)
{
  location_t num_teams_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t upper_loc = c_parser_peek_token (parser)->location;
      location_t lower_loc = UNKNOWN_LOCATION;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (upper_loc, expr, false, true);
      tree c, upper = expr.value, lower = NULL_TREE;
      upper = c_fully_fold (upper, false, NULL);

      if (c_parser_next_token_is (parser, CPP_COLON))
        {
          c_parser_consume_token (parser);
          lower_loc = upper_loc;
          lower = upper;
          upper_loc = c_parser_peek_token (parser)->location;
          expr = c_parser_expr_no_commas (parser, NULL);
          expr = convert_lvalue_to_rvalue (upper_loc, expr, false, true);
          upper = expr.value;
          upper = c_fully_fold (upper, false, NULL);
        }

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (upper))
          || (lower && !INTEGRAL_TYPE_P (TREE_TYPE (lower))))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't positive.  */
      c = fold_build2_loc (upper_loc, LE_EXPR, boolean_type_node, upper,
                           build_int_cst (TREE_TYPE (upper), 0));
      protected_set_expr_location (c, upper_loc);
      if (c == boolean_true_node)
        {
          warning_at (upper_loc, OPT_Wopenmp,
                      "%<num_teams%> value must be positive");
          upper = integer_one_node;
        }
      if (lower)
        {
          c = fold_build2_loc (lower_loc, LE_EXPR, boolean_type_node, lower,
                               build_int_cst (TREE_TYPE (lower), 0));
          protected_set_expr_location (c, lower_loc);
          if (c == boolean_true_node)
            {
              warning_at (lower_loc, OPT_Wopenmp,
                          "%<num_teams%> value must be positive");
              lower = NULL_TREE;
            }
          else if (TREE_CODE (lower) == INTEGER_CST
                   && TREE_CODE (upper) == INTEGER_CST
                   && tree_int_cst_lt (upper, lower))
            {
              warning_at (lower_loc, OPT_Wopenmp,
                          "%<num_teams%> lower bound %qE bigger than upper "
                          "bound %qE", lower, upper);
              lower = NULL_TREE;
            }
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_NUM_TEAMS, "num_teams");

      c = build_omp_clause (num_teams_loc, OMP_CLAUSE_NUM_TEAMS);
      OMP_CLAUSE_NUM_TEAMS_UPPER_EXPR (c) = upper;
      OMP_CLAUSE_NUM_TEAMS_LOWER_EXPR (c) = lower;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.0:
   thread_limit ( expression ) */

static tree
c_parser_omp_clause_thread_limit (c_parser *parser, tree list)
{
  location_t num_thread_limit_loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree c, t = expr.value;
      t = c_fully_fold (t, false, NULL);

      parens.skip_until_found_close (parser);

      if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
        {
          c_parser_error (parser, "expected integer expression");
          return list;
        }

      /* Attempt to statically determine when the number isn't positive.  */
      c = fold_build2_loc (expr_loc, LE_EXPR, boolean_type_node, t,
                           build_int_cst (TREE_TYPE (t), 0));
      protected_set_expr_location (c, expr_loc);
      if (c == boolean_true_node)
        {
          warning_at (expr_loc, OPT_Wopenmp,
                      "%<thread_limit%> value must be positive");
          t = integer_one_node;
        }

      check_no_duplicate_clause (list, OMP_CLAUSE_THREAD_LIMIT,
                                 "thread_limit");

      c = build_omp_clause (num_thread_limit_loc, OMP_CLAUSE_THREAD_LIMIT);
      OMP_CLAUSE_THREAD_LIMIT_EXPR (c) = t;
      OMP_CLAUSE_CHAIN (c) = list;
      list = c;
    }

  return list;
}

/* OpenMP 4.0:
   aligned ( variable-list )
   aligned ( variable-list : constant-expression ) */

static tree
c_parser_omp_clause_aligned (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree nl, c;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  nl = c_parser_omp_variable_list (parser, clause_loc,
                                   OMP_CLAUSE_ALIGNED, list);

  if (c_parser_next_token_is (parser, CPP_COLON))
    {
      c_parser_consume_token (parser);
      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      tree alignment = expr.value;
      alignment = c_fully_fold (alignment, false, NULL);
      if (TREE_CODE (alignment) != INTEGER_CST
          || !INTEGRAL_TYPE_P (TREE_TYPE (alignment))
          || tree_int_cst_sgn (alignment) != 1)
        {
          error_at (clause_loc, "%<aligned%> clause alignment expression must "
                                "be positive constant integer expression");
          alignment = NULL_TREE;
        }

      for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
        OMP_CLAUSE_ALIGNED_ALIGNMENT (c) = alignment;
    }

  parens.skip_until_found_close (parser);
  return nl;
}

/* OpenMP 5.0:
   allocate ( variable-list )
   allocate ( expression : variable-list )

   OpenMP 5.1:
   allocate ( allocator-modifier : variable-list )
   allocate ( allocator-modifier , allocator-modifier : variable-list )

   allocator-modifier:
   allocator ( expression )
   align ( expression )  */

static tree
c_parser_omp_clause_allocate (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree nl, c;
  tree allocator = NULL_TREE;
  tree align = NULL_TREE;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if ((c_parser_next_token_is_not (parser, CPP_NAME)
       && c_parser_next_token_is_not (parser, CPP_KEYWORD))
      || (c_parser_peek_2nd_token (parser)->type != CPP_COMMA
          && c_parser_peek_2nd_token (parser)->type != CPP_CLOSE_PAREN))
    {
      bool has_modifiers = false;
      tree orig_type = NULL_TREE;
      if (c_parser_next_token_is (parser, CPP_NAME)
          && c_parser_peek_2nd_token (parser)->type == CPP_OPEN_PAREN)
        {
          unsigned int n = 3;
          const char *p
            = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
          if ((strcmp (p, "allocator") == 0 || strcmp (p, "align") == 0)
              && c_parser_check_balanced_raw_token_sequence (parser, &n)
              && (c_parser_peek_nth_token_raw (parser, n)->type
                  == CPP_CLOSE_PAREN))
            {
              if (c_parser_peek_nth_token_raw (parser, n + 1)->type
                  == CPP_COLON)
                has_modifiers = true;
              else if (c_parser_peek_nth_token_raw (parser, n + 1)->type
                       == CPP_COMMA
                       && (c_parser_peek_nth_token_raw (parser, n + 2)->type
                           == CPP_NAME)
                       && (c_parser_peek_nth_token_raw (parser, n + 3)->type
                           == CPP_OPEN_PAREN))
                {
                  c_token *tok = c_parser_peek_nth_token_raw (parser, n + 2);
                  const char *q = IDENTIFIER_POINTER (tok->value);
                  n += 4;
                  if ((strcmp (q, "allocator") == 0
                       || strcmp (q, "align") == 0)
                      && c_parser_check_balanced_raw_token_sequence (parser,
                                                                     &n)
                      && (c_parser_peek_nth_token_raw (parser, n)->type
                          == CPP_CLOSE_PAREN)
                      && (c_parser_peek_nth_token_raw (parser, n + 1)->type
                          == CPP_COLON))
                    has_modifiers = true;
                }
            }
          if (has_modifiers)
            {
              c_parser_consume_token (parser);
              matching_parens parens2;;
              parens2.require_open (parser);
              location_t expr_loc = c_parser_peek_token (parser)->location;
              c_expr expr = c_parser_expr_no_commas (parser, NULL);
              expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
              if (expr.value == error_mark_node)
                ;
              else if (strcmp (p, "allocator") == 0)
                {
                  allocator = expr.value;
                  allocator = c_fully_fold (allocator, false, NULL);
                  orig_type = expr.original_type
                              ? expr.original_type : TREE_TYPE (allocator);
                  orig_type = TYPE_MAIN_VARIANT (orig_type);
                }
              else
                {
                  align = expr.value;
                  align = c_fully_fold (align, false, NULL);
                }
              parens2.skip_until_found_close (parser);
              if (c_parser_next_token_is (parser, CPP_COMMA))
                {
                  c_parser_consume_token (parser);
                  c_token *tok = c_parser_peek_token (parser);
                  const char *q = "";
                  if (c_parser_next_token_is (parser, CPP_NAME))
                    q = IDENTIFIER_POINTER (tok->value);
                  if (strcmp (q, "allocator") != 0 && strcmp (q, "align") != 0)
                    {
                      c_parser_error (parser, "expected %<allocator%> or "
                                              "%<align%>");
                      parens.skip_until_found_close (parser);
                      return list;
                    }
                  else if (strcmp (p, q) == 0)
                    {
                      error_at (tok->location, "duplicate %qs modifier", p);
                      parens.skip_until_found_close (parser);
                      return list;
                    }
                  c_parser_consume_token (parser);
                  if (!parens2.require_open (parser))
                    {
                      parens.skip_until_found_close (parser);
                      return list;
                    }
                  expr_loc = c_parser_peek_token (parser)->location;
                  expr = c_parser_expr_no_commas (parser, NULL);
                  expr = convert_lvalue_to_rvalue (expr_loc, expr, false,
                                                   true);
                  if (strcmp (q, "allocator") == 0)
                    {
                      allocator = expr.value;
                      allocator = c_fully_fold (allocator, false, NULL);
                      orig_type = expr.original_type
                                  ? expr.original_type : TREE_TYPE (allocator);
                      orig_type = TYPE_MAIN_VARIANT (orig_type);
                    }
                  else
                    {
                      align = expr.value;
                      align = c_fully_fold (align, false, NULL);
                    }
                  parens2.skip_until_found_close (parser);
                }
            }
        }
      if (!has_modifiers)
        {
          location_t expr_loc = c_parser_peek_token (parser)->location;
          c_expr expr = c_parser_expr_no_commas (parser, NULL);
          expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
          allocator = expr.value;
          allocator = c_fully_fold (allocator, false, NULL);
          orig_type = expr.original_type
                      ? expr.original_type : TREE_TYPE (allocator);
          orig_type = TYPE_MAIN_VARIANT (orig_type);
        }
      if (allocator
          && (!INTEGRAL_TYPE_P (TREE_TYPE (allocator))
              || TREE_CODE (orig_type) != ENUMERAL_TYPE
              || (TYPE_NAME (orig_type)
                  != get_identifier ("omp_allocator_handle_t"))))
        {
          error_at (clause_loc, "%<allocate%> clause allocator expression "
                                "has type %qT rather than "
                                "%<omp_allocator_handle_t%>",
                                TREE_TYPE (allocator));
          allocator = NULL_TREE;
        }
      if (align
          && (!INTEGRAL_TYPE_P (TREE_TYPE (align))
              || !tree_fits_uhwi_p (align)
              || !integer_pow2p (align)))
        {
          error_at (clause_loc, "%<allocate%> clause %<align%> modifier "
                                "argument needs to be positive constant "
                                "power of two integer expression");
          align = NULL_TREE;
        }
      if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        {
          parens.skip_until_found_close (parser);
          return list;
        }
    }

  nl = c_parser_omp_variable_list (parser, clause_loc,
                                   OMP_CLAUSE_ALLOCATE, list);

  if (allocator || align)
    for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
      {
        OMP_CLAUSE_ALLOCATE_ALLOCATOR (c) = allocator;
        OMP_CLAUSE_ALLOCATE_ALIGN (c) = align;
      }

  parens.skip_until_found_close (parser);
  return nl;
}

/* OpenMP 4.0:
   linear ( variable-list )
   linear ( variable-list : expression )

   OpenMP 4.5:
   linear ( modifier ( variable-list ) )
   linear ( modifier ( variable-list ) : expression )

   modifier:
     val

   OpenMP 5.2:
   linear ( variable-list : modifiers-list )

   modifiers:
     val
     step ( expression )  */

static tree
c_parser_omp_clause_linear (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree nl, c, step;
  enum omp_clause_linear_kind kind = OMP_CLAUSE_LINEAR_DEFAULT;
  bool old_linear_modifier = false;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      c_token *tok = c_parser_peek_token (parser);
      const char *p = IDENTIFIER_POINTER (tok->value);
      if (strcmp ("val", p) == 0)
        kind = OMP_CLAUSE_LINEAR_VAL;
      if (c_parser_peek_2nd_token (parser)->type != CPP_OPEN_PAREN)
        kind = OMP_CLAUSE_LINEAR_DEFAULT;
      if (kind != OMP_CLAUSE_LINEAR_DEFAULT)
        {
          old_linear_modifier = true;
          c_parser_consume_token (parser);
          c_parser_consume_token (parser);
        }
    }

  nl = c_parser_omp_variable_list (parser, clause_loc,
                                   OMP_CLAUSE_LINEAR, list);

  if (kind != OMP_CLAUSE_LINEAR_DEFAULT)
    parens.skip_until_found_close (parser);

  if (c_parser_next_token_is (parser, CPP_COLON))
    {
      c_parser_consume_token (parser);
      location_t expr_loc = c_parser_peek_token (parser)->location;
      bool has_modifiers = false;
      if (kind == OMP_CLAUSE_LINEAR_DEFAULT
          && c_parser_next_token_is (parser, CPP_NAME))
        {
          c_token *tok = c_parser_peek_token (parser);
          const char *p = IDENTIFIER_POINTER (tok->value);
          unsigned int pos = 0;
          if (strcmp ("val", p) == 0)
            pos = 2;
          else if (strcmp ("step", p) == 0
                   && c_parser_peek_2nd_token (parser)->type == CPP_OPEN_PAREN)
            {
              pos = 3;
              if (c_parser_check_balanced_raw_token_sequence (parser, &pos)
                  && (c_parser_peek_nth_token_raw (parser, pos)->type
                      == CPP_CLOSE_PAREN))
                ++pos;
              else
                pos = 0;
            }
          if (pos)
            {
              tok = c_parser_peek_nth_token_raw (parser, pos);
              if (tok->type == CPP_COMMA || tok->type == CPP_CLOSE_PAREN)
                has_modifiers = true;
            }
        }
      if (has_modifiers)
        {
          step = NULL_TREE;
          while (c_parser_next_token_is (parser, CPP_NAME))
            {
              c_token *tok = c_parser_peek_token (parser);
              const char *p = IDENTIFIER_POINTER (tok->value);
              if (strcmp ("val", p) == 0)
                {
                  if (kind != OMP_CLAUSE_LINEAR_DEFAULT)
                    error_at (tok->location, "multiple linear modifiers");
                  kind = OMP_CLAUSE_LINEAR_DEFAULT;
                  c_parser_consume_token (parser);
                }
              else if (strcmp ("step", p) == 0)
                {
                  c_parser_consume_token (parser);
                  matching_parens parens2;
                  if (parens2.require_open (parser))
                    {
                      if (step)
                        error_at (tok->location,
                                  "multiple %<step%> modifiers");
                      expr_loc = c_parser_peek_token (parser)->location;
                      c_expr expr = c_parser_expr_no_commas (parser, NULL);
                      expr = convert_lvalue_to_rvalue (expr_loc, expr, false,
                                                       true);
                      step = c_fully_fold (expr.value, false, NULL);
                      if (!INTEGRAL_TYPE_P (TREE_TYPE (step)))
                        {
                          error_at (clause_loc, "%<linear%> clause step "
                                                "expression must be integral");
                          step = integer_one_node;
                        }
                      parens2.skip_until_found_close (parser);
                    }
                  else
                    break;
                }
              else
                break;
              if (c_parser_next_token_is (parser, CPP_COMMA))
                {
                  c_parser_consume_token (parser);
                  continue;
                }
              break;
            }
          if (!step)
            step = integer_one_node;
        }
      else
        {
          c_expr expr = c_parser_expr_no_commas (parser, NULL);
          expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
          step = c_fully_fold (expr.value, false, NULL);
          if (!INTEGRAL_TYPE_P (TREE_TYPE (step)))
            {
              error_at (clause_loc, "%<linear%> clause step expression must "
                                    "be integral");
              step = integer_one_node;
            }
        }

    }
  else
    step = integer_one_node;

  for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
    {
      OMP_CLAUSE_LINEAR_STEP (c) = step;
      OMP_CLAUSE_LINEAR_KIND (c) = kind;
      OMP_CLAUSE_LINEAR_OLD_LINEAR_MODIFIER (c) = old_linear_modifier;
    }

  parens.skip_until_found_close (parser);
  return nl;
}

/* OpenMP 5.0:
   nontemporal ( variable-list ) */

static tree
c_parser_omp_clause_nontemporal (c_parser *parser, tree list)
{
  return c_parser_omp_var_list_parens (parser, OMP_CLAUSE_NONTEMPORAL, list);
}

/* OpenMP 4.0:
   safelen ( constant-expression ) */

static tree
c_parser_omp_clause_safelen (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree c, t;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  location_t expr_loc = c_parser_peek_token (parser)->location;
  c_expr expr = c_parser_expr_no_commas (parser, NULL);
  expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
  t = expr.value;
  t = c_fully_fold (t, false, NULL);
  if (TREE_CODE (t) != INTEGER_CST
      || !INTEGRAL_TYPE_P (TREE_TYPE (t))
      || tree_int_cst_sgn (t) != 1)
    {
      error_at (clause_loc, "%<safelen%> clause expression must "
                            "be positive constant integer expression");
      t = NULL_TREE;
    }

  parens.skip_until_found_close (parser);
  if (t == NULL_TREE || t == error_mark_node)
    return list;

  check_no_duplicate_clause (list, OMP_CLAUSE_SAFELEN, "safelen");

  c = build_omp_clause (clause_loc, OMP_CLAUSE_SAFELEN);
  OMP_CLAUSE_SAFELEN_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 4.0:
   simdlen ( constant-expression ) */

static tree
c_parser_omp_clause_simdlen (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree c, t;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  location_t expr_loc = c_parser_peek_token (parser)->location;
  c_expr expr = c_parser_expr_no_commas (parser, NULL);
  expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
  t = expr.value;
  t = c_fully_fold (t, false, NULL);
  if (TREE_CODE (t) != INTEGER_CST
      || !INTEGRAL_TYPE_P (TREE_TYPE (t))
      || tree_int_cst_sgn (t) != 1)
    {
      error_at (clause_loc, "%<simdlen%> clause expression must "
                            "be positive constant integer expression");
      t = NULL_TREE;
    }

  parens.skip_until_found_close (parser);
  if (t == NULL_TREE || t == error_mark_node)
    return list;

  check_no_duplicate_clause (list, OMP_CLAUSE_SIMDLEN, "simdlen");

  c = build_omp_clause (clause_loc, OMP_CLAUSE_SIMDLEN);
  OMP_CLAUSE_SIMDLEN_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 4.5:
   vec:
     identifier [+/- integer]
     vec , identifier [+/- integer]
*/

static tree
c_parser_omp_clause_doacross_sink (c_parser *parser, location_t clause_loc,
                                   tree list, bool depend_p)
{
  tree vec = NULL;
  if (c_parser_next_token_is_not (parser, CPP_NAME)
      || c_parser_peek_token (parser)->id_kind != C_ID_ID)
    {
      c_parser_error (parser, "expected identifier");
      return list;
    }

  if (!depend_p)
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "omp_cur_iteration") == 0
          && c_parser_peek_2nd_token (parser)->type == CPP_MINUS
          && c_parser_peek_nth_token (parser, 3)->type == CPP_NUMBER
          && c_parser_peek_nth_token (parser, 4)->type == CPP_CLOSE_PAREN)
        {
          tree val = c_parser_peek_nth_token (parser, 3)->value;
          if (integer_onep (val))
            {
              c_parser_consume_token (parser);
              c_parser_consume_token (parser);
              c_parser_consume_token (parser);
              tree u = build_omp_clause (clause_loc, OMP_CLAUSE_DOACROSS);
              OMP_CLAUSE_DOACROSS_KIND (u) = OMP_CLAUSE_DOACROSS_SINK;
              OMP_CLAUSE_CHAIN (u) = list;
              return u;
            }
        }
    }



  while (c_parser_next_token_is (parser, CPP_NAME)
         && c_parser_peek_token (parser)->id_kind == C_ID_ID)
    {
      tree t = lookup_name (c_parser_peek_token (parser)->value);
      tree addend = NULL;

      if (t == NULL_TREE)
        {
          undeclared_variable (c_parser_peek_token (parser)->location,
                               c_parser_peek_token (parser)->value);
          t = error_mark_node;
        }

      c_parser_consume_token (parser);

      bool neg = false;
      if (c_parser_next_token_is (parser, CPP_MINUS))
        neg = true;
      else if (!c_parser_next_token_is (parser, CPP_PLUS))
        {
          addend = integer_zero_node;
          neg = false;
          goto add_to_vector;
        }
      c_parser_consume_token (parser);

      if (c_parser_next_token_is_not (parser, CPP_NUMBER))
        {
          c_parser_error (parser, "expected integer");
          return list;
        }

      addend = c_parser_peek_token (parser)->value;
      if (TREE_CODE (addend) != INTEGER_CST)
        {
          c_parser_error (parser, "expected integer");
          return list;
        }
      c_parser_consume_token (parser);

    add_to_vector:
      if (t != error_mark_node)
        {
          vec = tree_cons (addend, t, vec);
          if (neg)
            OMP_CLAUSE_DOACROSS_SINK_NEGATIVE (vec) = 1;
        }

      if (c_parser_next_token_is_not (parser, CPP_COMMA)
          || c_parser_peek_2nd_token (parser)->type != CPP_NAME
          || c_parser_peek_2nd_token (parser)->id_kind != C_ID_ID)
        break;

      c_parser_consume_token (parser);
    }

  if (vec == NULL_TREE)
    return list;

  tree u = build_omp_clause (clause_loc, OMP_CLAUSE_DOACROSS);
  OMP_CLAUSE_DOACROSS_KIND (u) = OMP_CLAUSE_DOACROSS_SINK;
  OMP_CLAUSE_DOACROSS_DEPEND (u) = depend_p;
  OMP_CLAUSE_DECL (u) = nreverse (vec);
  OMP_CLAUSE_CHAIN (u) = list;
  return u;
}

/* OpenMP 5.0:
   iterators ( iterators-definition )

   iterators-definition:
     iterator-specifier
     iterator-specifier , iterators-definition

   iterator-specifier:
     identifier = range-specification
     iterator-type identifier = range-specification

   range-specification:
     begin : end
     begin : end : step  */

static tree
c_parser_omp_iterators (c_parser *parser)
{
  tree ret = NULL_TREE, *last = &ret;
  c_parser_consume_token (parser);

  push_scope ();

  matching_parens parens;
  if (!parens.require_open (parser))
    return error_mark_node;

  do
    {
      tree iter_type = NULL_TREE, type_expr = NULL_TREE;
      if (c_parser_next_tokens_start_typename (parser, cla_prefer_id))
        {
          struct c_type_name *type = c_parser_type_name (parser);
          if (type != NULL)
            iter_type = groktypename (type, &type_expr, NULL);
        }
      if (iter_type == NULL_TREE)
        iter_type = integer_type_node;

      location_t loc = c_parser_peek_token (parser)->location;
      if (!c_parser_next_token_is (parser, CPP_NAME))
        {
          c_parser_error (parser, "expected identifier");
          break;
        }

      tree id = c_parser_peek_token (parser)->value;
      c_parser_consume_token (parser);

      if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
        break;

      location_t eloc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (eloc, expr, true, false);
      tree begin = expr.value;

      if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
        break;

      eloc = c_parser_peek_token (parser)->location;
      expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (eloc, expr, true, false);
      tree end = expr.value;

      tree step = integer_one_node;
      if (c_parser_next_token_is (parser, CPP_COLON))
        {
          c_parser_consume_token (parser);
          eloc = c_parser_peek_token (parser)->location;
          expr = c_parser_expr_no_commas (parser, NULL);
          expr = convert_lvalue_to_rvalue (eloc, expr, true, false);
          step = expr.value;
        }

      tree iter_var = build_decl (loc, VAR_DECL, id, iter_type);
      DECL_ARTIFICIAL (iter_var) = 1;
      DECL_CONTEXT (iter_var) = current_function_decl;
      pushdecl (iter_var);

      *last = make_tree_vec (6);
      TREE_VEC_ELT (*last, 0) = iter_var;
      TREE_VEC_ELT (*last, 1) = begin;
      TREE_VEC_ELT (*last, 2) = end;
      TREE_VEC_ELT (*last, 3) = step;
      last = &TREE_CHAIN (*last);

      if (c_parser_next_token_is (parser, CPP_COMMA))
        {
          c_parser_consume_token (parser);
          continue;
        }
      break;
    }
  while (1);

  parens.skip_until_found_close (parser);
  return ret ? ret : error_mark_node;
}

/* OpenMP 5.0:
   affinity ( [aff-modifier :] variable-list )
   aff-modifier:
     iterator ( iterators-definition )  */

static tree
c_parser_omp_clause_affinity (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  tree nl, iterators = NULL_TREE;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      bool parse_iter = ((strcmp ("iterator", p) == 0)
                         && (c_parser_peek_2nd_token (parser)->type
                             == CPP_OPEN_PAREN));
      if (parse_iter)
        {
          unsigned n = 3;
          parse_iter = (c_parser_check_balanced_raw_token_sequence (parser, &n)
                        && (c_parser_peek_nth_token_raw (parser, n)->type
                            == CPP_CLOSE_PAREN)
                        && (c_parser_peek_nth_token_raw (parser, n + 1)->type
                            == CPP_COLON));
        }
      if (parse_iter)
        {
          iterators = c_parser_omp_iterators (parser);
          if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
            {
              if (iterators)
                pop_scope ();
              parens.skip_until_found_close (parser);
              return list;
            }
        }
    }
  nl = c_parser_omp_variable_list (parser, clause_loc, OMP_CLAUSE_AFFINITY,
                                   list);
  if (iterators)
    {
      tree block = pop_scope ();
      if (iterators != error_mark_node)
        {
          TREE_VEC_ELT (iterators, 5) = block;
          for (tree c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
            OMP_CLAUSE_DECL (c) = build_tree_list (iterators,
                                                   OMP_CLAUSE_DECL (c));
        }
    }

  parens.skip_until_found_close (parser);
  return nl;
}


/* OpenMP 4.0:
   depend ( depend-kind: variable-list )

   depend-kind:
     in | out | inout

   OpenMP 4.5:
   depend ( source )

   depend ( sink  : vec )

   OpenMP 5.0:
   depend ( depend-modifier , depend-kind: variable-list )

   depend-kind:
     in | out | inout | mutexinoutset | depobj | inoutset

   depend-modifier:
     iterator ( iterators-definition )  */

static tree
c_parser_omp_clause_depend (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  enum omp_clause_depend_kind kind = OMP_CLAUSE_DEPEND_LAST;
  enum omp_clause_doacross_kind dkind = OMP_CLAUSE_DOACROSS_LAST;
  tree nl, c, iterators = NULL_TREE;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  do
    {
      if (c_parser_next_token_is_not (parser, CPP_NAME))
        goto invalid_kind;

      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp ("iterator", p) == 0 && iterators == NULL_TREE)
        {
          iterators = c_parser_omp_iterators (parser);
          c_parser_require (parser, CPP_COMMA, "expected %<,%>");
          continue;
        }
      if (strcmp ("in", p) == 0)
        kind = OMP_CLAUSE_DEPEND_IN;
      else if (strcmp ("inout", p) == 0)
        kind = OMP_CLAUSE_DEPEND_INOUT;
      else if (strcmp ("inoutset", p) == 0)
        kind = OMP_CLAUSE_DEPEND_INOUTSET;
      else if (strcmp ("mutexinoutset", p) == 0)
        kind = OMP_CLAUSE_DEPEND_MUTEXINOUTSET;
      else if (strcmp ("out", p) == 0)
        kind = OMP_CLAUSE_DEPEND_OUT;
      else if (strcmp ("depobj", p) == 0)
        kind = OMP_CLAUSE_DEPEND_DEPOBJ;
      else if (strcmp ("sink", p) == 0)
        dkind = OMP_CLAUSE_DOACROSS_SINK;
      else if (strcmp ("source", p) == 0)
        dkind = OMP_CLAUSE_DOACROSS_SOURCE;
      else
        goto invalid_kind;
      break;
    }
  while (1);

  c_parser_consume_token (parser);

  if (iterators
      && (dkind == OMP_CLAUSE_DOACROSS_SOURCE
          || dkind == OMP_CLAUSE_DOACROSS_SINK))
    {
      pop_scope ();
      error_at (clause_loc, "%<iterator%> modifier incompatible with %qs",
                dkind == OMP_CLAUSE_DOACROSS_SOURCE ? "source" : "sink");
      iterators = NULL_TREE;
    }

  if (dkind == OMP_CLAUSE_DOACROSS_SOURCE)
    {
      c = build_omp_clause (clause_loc, OMP_CLAUSE_DOACROSS);
      OMP_CLAUSE_DOACROSS_KIND (c) = dkind;
      OMP_CLAUSE_DOACROSS_DEPEND (c) = 1;
      OMP_CLAUSE_DECL (c) = NULL_TREE;
      OMP_CLAUSE_CHAIN (c) = list;
      parens.skip_until_found_close (parser);
      return c;
    }

  if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
    goto resync_fail;

  if (dkind == OMP_CLAUSE_DOACROSS_SINK)
    nl = c_parser_omp_clause_doacross_sink (parser, clause_loc, list, true);
  else
    {
      nl = c_parser_omp_variable_list (parser, clause_loc,
                                       OMP_CLAUSE_DEPEND, list);

      if (iterators)
        {
          tree block = pop_scope ();
          if (iterators == error_mark_node)
            iterators = NULL_TREE;
          else
            TREE_VEC_ELT (iterators, 5) = block;
        }

      for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
        {
          OMP_CLAUSE_DEPEND_KIND (c) = kind;
          if (iterators)
            OMP_CLAUSE_DECL (c)
              = build_tree_list (iterators, OMP_CLAUSE_DECL (c));
        }
    }

  parens.skip_until_found_close (parser);
  return nl;

 invalid_kind:
  c_parser_error (parser, "invalid depend kind");
 resync_fail:
  parens.skip_until_found_close (parser);
  if (iterators)
    pop_scope ();
  return list;
}

/* OpenMP 5.2:
   doacross ( source : )
   doacross ( source : omp_cur_iteration )

   doacross ( sink : vec )
   doacross ( sink : omp_cur_iteration - logical_iteration )  */

static tree
c_parser_omp_clause_doacross (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  enum omp_clause_doacross_kind kind = OMP_CLAUSE_DOACROSS_LAST;
  tree nl;
  const char *p;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is_not (parser, CPP_NAME))
    goto invalid_kind;

  p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp ("sink", p) == 0)
    kind = OMP_CLAUSE_DOACROSS_SINK;
  else if (strcmp ("source", p) == 0)
    kind = OMP_CLAUSE_DOACROSS_SOURCE;
  else
    goto invalid_kind;

  c_parser_consume_token (parser);

  if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
    goto resync_fail;

  if (kind == OMP_CLAUSE_DOACROSS_SOURCE)
    {
      if (c_parser_next_token_is (parser, CPP_NAME)
          && strcmp (IDENTIFIER_POINTER (c_parser_peek_token (parser)->value),
                     "omp_cur_iteration") == 0)
        c_parser_consume_token (parser);
      nl = build_omp_clause (clause_loc, OMP_CLAUSE_DOACROSS);
      OMP_CLAUSE_DOACROSS_KIND (nl) = OMP_CLAUSE_DOACROSS_SOURCE;
      OMP_CLAUSE_DECL (nl) = NULL_TREE;
      OMP_CLAUSE_CHAIN (nl) = list;
    }
  else
    nl = c_parser_omp_clause_doacross_sink (parser, clause_loc, list, false);

  parens.skip_until_found_close (parser);
  return nl;

 invalid_kind:
  c_parser_error (parser, "invalid doacross kind");
 resync_fail:
  parens.skip_until_found_close (parser);
  return list;
}

/* OpenMP 4.0:
   map ( map-kind: variable-list )
   map ( variable-list )

   map-kind:
     alloc | to | from | tofrom

   OpenMP 4.5:
   map-kind:
     alloc | to | from | tofrom | release | delete

   map ( always [,] map-kind: variable-list )

   OpenMP 5.0:
   map ( [map-type-modifier[,] ...] map-kind: variable-list )

   map-type-modifier:
     always | close */

static tree
c_parser_omp_clause_map (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  enum gomp_map_kind kind = GOMP_MAP_TOFROM;
  tree nl, c;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  int pos = 1;
  int map_kind_pos = 0;
  while (c_parser_peek_nth_token_raw (parser, pos)->type == CPP_NAME)
    {
      if (c_parser_peek_nth_token_raw (parser, pos + 1)->type == CPP_COLON)
        {
          map_kind_pos = pos;
          break;
        }

      if (c_parser_peek_nth_token_raw (parser, pos + 1)->type == CPP_COMMA)
        pos++;
      pos++;
    }

  int always_modifier = 0;
  int close_modifier = 0;
  int present_modifier = 0;
  for (int pos = 1; pos < map_kind_pos; ++pos)
    {
      c_token *tok = c_parser_peek_token (parser);

      if (tok->type == CPP_COMMA)
        {
          c_parser_consume_token (parser);
          continue;
        }

      const char *p = IDENTIFIER_POINTER (tok->value);
      if (strcmp ("always", p) == 0)
        {
          if (always_modifier)
            {
              c_parser_error (parser, "too many %<always%> modifiers");
              parens.skip_until_found_close (parser);
              return list;
            }
          always_modifier++;
        }
      else if (strcmp ("close", p) == 0)
        {
          if (close_modifier)
            {
              c_parser_error (parser, "too many %<close%> modifiers");
              parens.skip_until_found_close (parser);
              return list;
            }
          close_modifier++;
        }
      else if (strcmp ("present", p) == 0)
        {
          if (present_modifier)
            {
              c_parser_error (parser, "too many %<present%> modifiers");
              parens.skip_until_found_close (parser);
              return list;
            }
          present_modifier++;
        }
      else
        {
          c_parser_error (parser, "%<map%> clause with map-type modifier other "
                                  "than %<always%>, %<close%> or %<present%>");
          parens.skip_until_found_close (parser);
          return list;
        }

        c_parser_consume_token (parser);
    }

  if (c_parser_next_token_is (parser, CPP_NAME)
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      int always_present_modifier = always_modifier && present_modifier;

      if (strcmp ("alloc", p) == 0)
        kind = present_modifier ? GOMP_MAP_PRESENT_ALLOC : GOMP_MAP_ALLOC;
      else if (strcmp ("to", p) == 0)
        kind = (always_present_modifier ? GOMP_MAP_ALWAYS_PRESENT_TO
                : present_modifier ? GOMP_MAP_PRESENT_TO
                : always_modifier ? GOMP_MAP_ALWAYS_TO
                : GOMP_MAP_TO);
      else if (strcmp ("from", p) == 0)
        kind = (always_present_modifier ? GOMP_MAP_ALWAYS_PRESENT_FROM
                : present_modifier ? GOMP_MAP_PRESENT_FROM
                : always_modifier ? GOMP_MAP_ALWAYS_FROM
                : GOMP_MAP_FROM);
      else if (strcmp ("tofrom", p) == 0)
        kind = (always_present_modifier ? GOMP_MAP_ALWAYS_PRESENT_TOFROM
                : present_modifier ? GOMP_MAP_PRESENT_TOFROM
                : always_modifier ? GOMP_MAP_ALWAYS_TOFROM
                : GOMP_MAP_TOFROM);
      else if (strcmp ("release", p) == 0)
        kind = GOMP_MAP_RELEASE;
      else if (strcmp ("delete", p) == 0)
        kind = GOMP_MAP_DELETE;
      else
        {
          c_parser_error (parser, "invalid map kind");
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                     "expected %<)%>");
          return list;
        }
      c_parser_consume_token (parser);
      c_parser_consume_token (parser);
    }

  nl = c_parser_omp_variable_list (parser, clause_loc, OMP_CLAUSE_MAP, list,
                                   true);

  for (c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
    OMP_CLAUSE_SET_MAP_KIND (c, kind);

  parens.skip_until_found_close (parser);
  return nl;
}

/* OpenMP 4.0:
   device ( expression )

   OpenMP 5.0:
   device ( [device-modifier :] integer-expression )

   device-modifier:
     ancestor | device_num */

static tree
c_parser_omp_clause_device (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  location_t expr_loc;
  c_expr expr;
  tree c, t;
  bool ancestor = false;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is (parser, CPP_NAME)
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    {
      c_token *tok = c_parser_peek_token (parser);
      const char *p = IDENTIFIER_POINTER (tok->value);
      if (strcmp ("ancestor", p) == 0)
        {
          /* A requires directive with the reverse_offload clause must be
          specified.  */
          if ((omp_requires_mask & OMP_REQUIRES_REVERSE_OFFLOAD) == 0)
            {
              error_at (tok->location, "%<ancestor%> device modifier not "
                                       "preceded by %<requires%> directive "
                                       "with %<reverse_offload%> clause");
              parens.skip_until_found_close (parser);
              return list;
            }
          ancestor = true;
        }
      else if (strcmp ("device_num", p) == 0)
        ;
      else
        {
          error_at (tok->location, "expected %<ancestor%> or %<device_num%>");
          parens.skip_until_found_close (parser);
          return list;
        }
      c_parser_consume_token (parser);
      c_parser_consume_token (parser);
    }

  expr_loc = c_parser_peek_token (parser)->location;
  expr = c_parser_expr_no_commas (parser, NULL);
  expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
  t = expr.value;
  t = c_fully_fold (t, false, NULL);

  parens.skip_until_found_close (parser);

  if (!INTEGRAL_TYPE_P (TREE_TYPE (t)))
    {
      c_parser_error (parser, "expected integer expression");
      return list;
    }
  if (ancestor && TREE_CODE (t) == INTEGER_CST && !integer_onep (t))
    {
      error_at (expr_loc, "the %<device%> clause expression must evaluate to "
                          "%<1%>");
      return list;
    }

  check_no_duplicate_clause (list, OMP_CLAUSE_DEVICE, "device");

  c = build_omp_clause (clause_loc, OMP_CLAUSE_DEVICE);

  OMP_CLAUSE_DEVICE_ID (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  OMP_CLAUSE_DEVICE_ANCESTOR (c) = ancestor;

  list = c;
  return list;
}

/* OpenMP 4.0:
   dist_schedule ( static )
   dist_schedule ( static , expression ) */

static tree
c_parser_omp_clause_dist_schedule (c_parser *parser, tree list)
{
  tree c, t = NULL_TREE;
  location_t loc = c_parser_peek_token (parser)->location;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (!c_parser_next_token_is_keyword (parser, RID_STATIC))
    {
      c_parser_error (parser, "invalid dist_schedule kind");
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                 "expected %<)%>");
      return list;
    }

  c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_COMMA))
    {
      c_parser_consume_token (parser);

      location_t expr_loc = c_parser_peek_token (parser)->location;
      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      t = expr.value;
      t = c_fully_fold (t, false, NULL);
      parens.skip_until_found_close (parser);
    }
  else
    c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                               "expected %<,%> or %<)%>");

  /* check_no_duplicate_clause (list, OMP_CLAUSE_DIST_SCHEDULE,
                                "dist_schedule"); */
  if (omp_find_clause (list, OMP_CLAUSE_DIST_SCHEDULE))
    warning_at (loc, OPT_Wopenmp, "too many %qs clauses", "dist_schedule");
  if (t == error_mark_node)
    return list;

  c = build_omp_clause (loc, OMP_CLAUSE_DIST_SCHEDULE);
  OMP_CLAUSE_DIST_SCHEDULE_CHUNK_EXPR (c) = t;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;
}

/* OpenMP 4.0:
   proc_bind ( proc-bind-kind )

   proc-bind-kind:
     primary | master | close | spread
   where OpenMP 5.1 added 'primary' and deprecated the alias 'master'.  */

static tree
c_parser_omp_clause_proc_bind (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  enum omp_clause_proc_bind_kind kind;
  tree c;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp ("primary", p) == 0)
        kind = OMP_CLAUSE_PROC_BIND_PRIMARY;
      else if (strcmp ("master", p) == 0)
        kind = OMP_CLAUSE_PROC_BIND_MASTER;
      else if (strcmp ("close", p) == 0)
        kind = OMP_CLAUSE_PROC_BIND_CLOSE;
      else if (strcmp ("spread", p) == 0)
        kind = OMP_CLAUSE_PROC_BIND_SPREAD;
      else
        goto invalid_kind;
    }
  else
    goto invalid_kind;

  check_no_duplicate_clause (list, OMP_CLAUSE_PROC_BIND, "proc_bind");
  c_parser_consume_token (parser);
  parens.skip_until_found_close (parser);
  c = build_omp_clause (clause_loc, OMP_CLAUSE_PROC_BIND);
  OMP_CLAUSE_PROC_BIND_KIND (c) = kind;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;

 invalid_kind:
  c_parser_error (parser, "invalid proc_bind kind");
  parens.skip_until_found_close (parser);
  return list;
}

/* OpenMP 5.0:
   device_type ( host | nohost | any )  */

static tree
c_parser_omp_clause_device_type (c_parser *parser, tree list)
{
  location_t clause_loc = c_parser_peek_token (parser)->location;
  enum omp_clause_device_type_kind kind;
  tree c;

  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp ("host", p) == 0)
        kind = OMP_CLAUSE_DEVICE_TYPE_HOST;
      else if (strcmp ("nohost", p) == 0)
        kind = OMP_CLAUSE_DEVICE_TYPE_NOHOST;
      else if (strcmp ("any", p) == 0)
        kind = OMP_CLAUSE_DEVICE_TYPE_ANY;
      else
        goto invalid_kind;
    }
  else
    goto invalid_kind;

  check_no_duplicate_clause (list, OMP_CLAUSE_DEVICE_TYPE,
                             "device_type");
  c_parser_consume_token (parser);
  parens.skip_until_found_close (parser);
  c = build_omp_clause (clause_loc, OMP_CLAUSE_DEVICE_TYPE);
  OMP_CLAUSE_DEVICE_TYPE_KIND (c) = kind;
  OMP_CLAUSE_CHAIN (c) = list;
  return c;

 invalid_kind:
  c_parser_error (parser, "expected %<host%>, %<nohost%> or %<any%>");
  parens.skip_until_found_close (parser);
  return list;
}

/* OpenMP 4.0:
   from ( variable-list )
   to ( variable-list )

   OpenMP 5.1:
   from ( [present :] variable-list )
   to ( [present :] variable-list ) */

static tree
c_parser_omp_clause_from_to (c_parser *parser, enum omp_clause_code kind,
                             tree list)
{
  location_t loc = c_parser_peek_token (parser)->location;
  matching_parens parens;
  if (!parens.require_open (parser))
    return list;

  bool present = false;
  c_token *token = c_parser_peek_token (parser);

  if (token->type == CPP_NAME
      && strcmp (IDENTIFIER_POINTER (token->value), "present") == 0
      && c_parser_peek_2nd_token (parser)->type == CPP_COLON)
    {
      present = true;
      c_parser_consume_token (parser);
      c_parser_consume_token (parser);
    }

  tree nl = c_parser_omp_variable_list (parser, loc, kind, list);
  parens.skip_until_found_close (parser);

  if (present)
    for (tree c = nl; c != list; c = OMP_CLAUSE_CHAIN (c))
      OMP_CLAUSE_MOTION_PRESENT (c) = 1;

  return nl;
}

/* OpenMP 4.0:
   uniform ( variable-list ) */

static tree
c_parser_omp_clause_uniform (c_parser *parser, tree list)
{
  /* The clauses location.  */
  location_t loc = c_parser_peek_token (parser)->location;

  matching_parens parens;
  if (parens.require_open (parser))
    {
      list = c_parser_omp_variable_list (parser, loc, OMP_CLAUSE_UNIFORM,
                                         list);
      parens.skip_until_found_close (parser);
    }
  return list;
}

/* OpenMP 5.0:
   detach ( event-handle ) */

static tree
c_parser_omp_clause_detach (c_parser *parser, tree list)
{
  matching_parens parens;
  location_t clause_loc = c_parser_peek_token (parser)->location;

  if (!parens.require_open (parser))
    return list;

  if (c_parser_next_token_is_not (parser, CPP_NAME)
      || c_parser_peek_token (parser)->id_kind != C_ID_ID)
    {
      c_parser_error (parser, "expected identifier");
      parens.skip_until_found_close (parser);
      return list;
    }

  tree t = lookup_name (c_parser_peek_token (parser)->value);
  if (t == NULL_TREE)
    {
      undeclared_variable (c_parser_peek_token (parser)->location,
                           c_parser_peek_token (parser)->value);
      parens.skip_until_found_close (parser);
      return list;
    }
  c_parser_consume_token (parser);

  tree type = TYPE_MAIN_VARIANT (TREE_TYPE (t));
  if (!INTEGRAL_TYPE_P (type)
      || TREE_CODE (type) != ENUMERAL_TYPE
      || TYPE_NAME (type) != get_identifier ("omp_event_handle_t"))
    {
      error_at (clause_loc, "%<detach%> clause event handle "
                            "has type %qT rather than "
                            "%<omp_event_handle_t%>",
                            type);
      parens.skip_until_found_close (parser);
      return list;
    }

  tree u = build_omp_clause (clause_loc, OMP_CLAUSE_DETACH);
  OMP_CLAUSE_DECL (u) = t;
  OMP_CLAUSE_CHAIN (u) = list;
  parens.skip_until_found_close (parser);
  return u;
}

/* Parse all OpenACC clauses.  The set clauses allowed by the directive
   is a bitmask in MASK.  Return the list of clauses found.  */

static tree
c_parser_oacc_all_clauses (c_parser *parser, omp_clause_mask mask,
                           const char *where, bool finish_p = true,
                           bool target_p = false)
{
  tree clauses = NULL;
  bool first = true;

  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      location_t here;
      pragma_omp_clause c_kind;
      const char *c_name;
      tree prev = clauses;

      if (!first && c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);

      here = c_parser_peek_token (parser)->location;
      c_kind = c_parser_omp_clause_name (parser);

      switch (c_kind)
        {
        case PRAGMA_OACC_CLAUSE_ASYNC:
          clauses = c_parser_oacc_clause_async (parser, clauses);
          c_name = "async";
          break;
        case PRAGMA_OACC_CLAUSE_AUTO:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_AUTO,
                                                 clauses);
          c_name = "auto";
          break;
        case PRAGMA_OACC_CLAUSE_ATTACH:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "attach";
          break;
        case PRAGMA_OACC_CLAUSE_COLLAPSE:
          clauses = c_parser_omp_clause_collapse (parser, clauses);
          c_name = "collapse";
          break;
        case PRAGMA_OACC_CLAUSE_COPY:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "copy";
          break;
        case PRAGMA_OACC_CLAUSE_COPYIN:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "copyin";
          break;
        case PRAGMA_OACC_CLAUSE_COPYOUT:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "copyout";
          break;
        case PRAGMA_OACC_CLAUSE_CREATE:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "create";
          break;
        case PRAGMA_OACC_CLAUSE_DELETE:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "delete";
          break;
        case PRAGMA_OMP_CLAUSE_DEFAULT:
          clauses = c_parser_omp_clause_default (parser, clauses, true);
          c_name = "default";
          break;
        case PRAGMA_OACC_CLAUSE_DETACH:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "detach";
          break;
        case PRAGMA_OACC_CLAUSE_DEVICE:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "device";
          break;
        case PRAGMA_OACC_CLAUSE_DEVICEPTR:
          clauses = c_parser_oacc_data_clause_deviceptr (parser, clauses);
          c_name = "deviceptr";
          break;
        case PRAGMA_OACC_CLAUSE_DEVICE_RESIDENT:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "device_resident";
          break;
        case PRAGMA_OACC_CLAUSE_FINALIZE:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_FINALIZE,
                                                 clauses);
          c_name = "finalize";
          break;
        case PRAGMA_OACC_CLAUSE_FIRSTPRIVATE:
          clauses = c_parser_omp_clause_firstprivate (parser, clauses);
          c_name = "firstprivate";
          break;
        case PRAGMA_OACC_CLAUSE_GANG:
          c_name = "gang";
          clauses = c_parser_oacc_shape_clause (parser, here, OMP_CLAUSE_GANG,
                                                c_name, clauses);
          break;
        case PRAGMA_OACC_CLAUSE_HOST:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "host";
          break;
        case PRAGMA_OACC_CLAUSE_IF:
          clauses = c_parser_omp_clause_if (parser, clauses, false);
          c_name = "if";
          break;
        case PRAGMA_OACC_CLAUSE_IF_PRESENT:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_IF_PRESENT,
                                                 clauses);
          c_name = "if_present";
          break;
        case PRAGMA_OACC_CLAUSE_INDEPENDENT:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_INDEPENDENT,
                                                 clauses);
          c_name = "independent";
          break;
        case PRAGMA_OACC_CLAUSE_LINK:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "link";
          break;
        case PRAGMA_OACC_CLAUSE_NO_CREATE:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "no_create";
          break;
        case PRAGMA_OACC_CLAUSE_NOHOST:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_NOHOST,
                                                 clauses);
          c_name = "nohost";
          break;
        case PRAGMA_OACC_CLAUSE_NUM_GANGS:
          clauses = c_parser_oacc_single_int_clause (parser,
                                                     OMP_CLAUSE_NUM_GANGS,
                                                     clauses);
          c_name = "num_gangs";
          break;
        case PRAGMA_OACC_CLAUSE_NUM_WORKERS:
          clauses = c_parser_oacc_single_int_clause (parser,
                                                     OMP_CLAUSE_NUM_WORKERS,
                                                     clauses);
          c_name = "num_workers";
          break;
        case PRAGMA_OACC_CLAUSE_PRESENT:
          clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "present";
          break;
        case PRAGMA_OACC_CLAUSE_PRIVATE:
          clauses = c_parser_omp_clause_private (parser, clauses);
          c_name = "private";
          break;
        case PRAGMA_OACC_CLAUSE_REDUCTION:
          clauses
            = c_parser_omp_clause_reduction (parser, OMP_CLAUSE_REDUCTION,
                                             false, clauses);
          c_name = "reduction";
          break;
        case PRAGMA_OACC_CLAUSE_SELF:
          if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_HOST)) == 0)
            /* OpenACC compute construct */
            clauses = c_parser_oacc_compute_clause_self (parser, clauses);
          else
            /* OpenACC 'update' directive */
            clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
          c_name = "self";
          break;
        case PRAGMA_OACC_CLAUSE_SEQ:
          clauses = c_parser_oacc_simple_clause (here, OMP_CLAUSE_SEQ,
                                                 clauses);
          c_name = "seq";
          break;
        case PRAGMA_OACC_CLAUSE_TILE:
          clauses = c_parser_oacc_clause_tile (parser, clauses);
          c_name = "tile";
          break;
        case PRAGMA_OACC_CLAUSE_USE_DEVICE:
          clauses = c_parser_omp_clause_use_device_ptr (parser, clauses);
          c_name = "use_device";
          break;
        case PRAGMA_OACC_CLAUSE_VECTOR:
          c_name = "vector";
          clauses = c_parser_oacc_shape_clause (parser, here, OMP_CLAUSE_VECTOR,
                                                c_name, clauses);
          break;
        case PRAGMA_OACC_CLAUSE_VECTOR_LENGTH:
          clauses = c_parser_oacc_single_int_clause (parser,
                                                     OMP_CLAUSE_VECTOR_LENGTH,
                                                     clauses);
          c_name = "vector_length";
          break;
        case PRAGMA_OACC_CLAUSE_WAIT:
          clauses = c_parser_oacc_clause_wait (parser, clauses);
          c_name = "wait";
          break;
        case PRAGMA_OACC_CLAUSE_WORKER:
          c_name = "worker";
          clauses = c_parser_oacc_shape_clause (parser, here, OMP_CLAUSE_WORKER,
                                                c_name, clauses);
          break;
        default:
          c_parser_error (parser, "expected an OpenACC clause");
          goto saw_error;
        }

      first = false;

      if (((mask >> c_kind) & 1) == 0)
        {
          /* Remove the invalid clause(s) from the list to avoid
             confusing the rest of the compiler.  */
          clauses = prev;
          error_at (here, "%qs is not valid for %qs", c_name, where);
        }
    }

 saw_error:
  c_parser_skip_to_pragma_eol (parser);

  if (finish_p)
    return c_finish_omp_clauses (clauses, target_p ? C_ORT_ACC_TARGET
                                                   : C_ORT_ACC);

  return clauses;
}

/* Parse all OpenMP clauses.  The set clauses allowed by the directive
   is a bitmask in MASK.  Return the list of clauses found.
   FINISH_P set if c_finish_omp_clauses should be called.
   NESTED non-zero if clauses should be terminated by closing paren instead
   of end of pragma.  If it is 2, additionally commas are required in between
   the clauses.  */

static tree
c_parser_omp_all_clauses (c_parser *parser, omp_clause_mask mask,
                          const char *where, bool finish_p = true,
                          int nested = 0)
{
  tree clauses = NULL;
  bool first = true;

  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      location_t here;
      pragma_omp_clause c_kind;
      const char *c_name;
      tree prev = clauses;

      if (nested && c_parser_next_token_is (parser, CPP_CLOSE_PAREN))
        break;

      if (!first || nested != 2)
        {
          if (c_parser_next_token_is (parser, CPP_COMMA))
            c_parser_consume_token (parser);
          else if (nested == 2)
            error_at (c_parser_peek_token (parser)->location,
                      "clauses in %<simd%> trait should be separated "
                      "by %<,%>");
        }

      here = c_parser_peek_token (parser)->location;
      c_kind = c_parser_omp_clause_name (parser);

      switch (c_kind)
        {
        case PRAGMA_OMP_CLAUSE_BIND:
          clauses = c_parser_omp_clause_bind (parser, clauses);
          c_name = "bind";
          break;
        case PRAGMA_OMP_CLAUSE_COLLAPSE:
          clauses = c_parser_omp_clause_collapse (parser, clauses);
          c_name = "collapse";
          break;
        case PRAGMA_OMP_CLAUSE_COPYIN:
          clauses = c_parser_omp_clause_copyin (parser, clauses);
          c_name = "copyin";
          break;
        case PRAGMA_OMP_CLAUSE_COPYPRIVATE:
          clauses = c_parser_omp_clause_copyprivate (parser, clauses);
          c_name = "copyprivate";
          break;
        case PRAGMA_OMP_CLAUSE_DEFAULT:
          clauses = c_parser_omp_clause_default (parser, clauses, false);
          c_name = "default";
          break;
        case PRAGMA_OMP_CLAUSE_DETACH:
          clauses = c_parser_omp_clause_detach (parser, clauses);
          c_name = "detach";
          break;
        case PRAGMA_OMP_CLAUSE_FILTER:
          clauses = c_parser_omp_clause_filter (parser, clauses);
          c_name = "filter";
          break;
        case PRAGMA_OMP_CLAUSE_FIRSTPRIVATE:
          clauses = c_parser_omp_clause_firstprivate (parser, clauses);
          c_name = "firstprivate";
          break;
        case PRAGMA_OMP_CLAUSE_FINAL:
          clauses = c_parser_omp_clause_final (parser, clauses);
          c_name = "final";
          break;
        case PRAGMA_OMP_CLAUSE_GRAINSIZE:
          clauses = c_parser_omp_clause_grainsize (parser, clauses);
          c_name = "grainsize";
          break;
        case PRAGMA_OMP_CLAUSE_HINT:
          clauses = c_parser_omp_clause_hint (parser, clauses);
          c_name = "hint";
          break;
        case PRAGMA_OMP_CLAUSE_DEFAULTMAP:
          clauses = c_parser_omp_clause_defaultmap (parser, clauses);
          c_name = "defaultmap";
          break;
        case PRAGMA_OMP_CLAUSE_IF:
          clauses = c_parser_omp_clause_if (parser, clauses, true);
          c_name = "if";
          break;
        case PRAGMA_OMP_CLAUSE_IN_REDUCTION:
          clauses
            = c_parser_omp_clause_reduction (parser, OMP_CLAUSE_IN_REDUCTION,
                                             true, clauses);
          c_name = "in_reduction";
          break;
        case PRAGMA_OMP_CLAUSE_INDIRECT:
          clauses = c_parser_omp_clause_indirect (parser, clauses);
          c_name = "indirect";
          break;
        case PRAGMA_OMP_CLAUSE_LASTPRIVATE:
          clauses = c_parser_omp_clause_lastprivate (parser, clauses);
          c_name = "lastprivate";
          break;
        case PRAGMA_OMP_CLAUSE_MERGEABLE:
          clauses = c_parser_omp_clause_mergeable (parser, clauses);
          c_name = "mergeable";
          break;
        case PRAGMA_OMP_CLAUSE_NOWAIT:
          clauses = c_parser_omp_clause_nowait (parser, clauses);
          c_name = "nowait";
          break;
        case PRAGMA_OMP_CLAUSE_NUM_TASKS:
          clauses = c_parser_omp_clause_num_tasks (parser, clauses);
          c_name = "num_tasks";
          break;
        case PRAGMA_OMP_CLAUSE_NUM_THREADS:
          clauses = c_parser_omp_clause_num_threads (parser, clauses);
          c_name = "num_threads";
          break;
        case PRAGMA_OMP_CLAUSE_ORDER:
          clauses = c_parser_omp_clause_order (parser, clauses);
          c_name = "order";
          break;
        case PRAGMA_OMP_CLAUSE_ORDERED:
          clauses = c_parser_omp_clause_ordered (parser, clauses);
          c_name = "ordered";
          break;
        case PRAGMA_OMP_CLAUSE_PRIORITY:
          clauses = c_parser_omp_clause_priority (parser, clauses);
          c_name = "priority";
          break;
        case PRAGMA_OMP_CLAUSE_PRIVATE:
          clauses = c_parser_omp_clause_private (parser, clauses);
          c_name = "private";
          break;
        case PRAGMA_OMP_CLAUSE_REDUCTION:
          clauses
            = c_parser_omp_clause_reduction (parser, OMP_CLAUSE_REDUCTION,
                                             true, clauses);
          c_name = "reduction";
          break;
        case PRAGMA_OMP_CLAUSE_SCHEDULE:
          clauses = c_parser_omp_clause_schedule (parser, clauses);
          c_name = "schedule";
          break;
        case PRAGMA_OMP_CLAUSE_SHARED:
          clauses = c_parser_omp_clause_shared (parser, clauses);
          c_name = "shared";
          break;
        case PRAGMA_OMP_CLAUSE_TASK_REDUCTION:
          clauses
            = c_parser_omp_clause_reduction (parser, OMP_CLAUSE_TASK_REDUCTION,
                                             true, clauses);
          c_name = "task_reduction";
          break;
        case PRAGMA_OMP_CLAUSE_UNTIED:
          clauses = c_parser_omp_clause_untied (parser, clauses);
          c_name = "untied";
          break;
        case PRAGMA_OMP_CLAUSE_INBRANCH:
          clauses = c_parser_omp_clause_branch (parser, OMP_CLAUSE_INBRANCH,
                                                clauses);
          c_name = "inbranch";
          break;
        case PRAGMA_OMP_CLAUSE_NONTEMPORAL:
          clauses = c_parser_omp_clause_nontemporal (parser, clauses);
          c_name = "nontemporal";
          break;
        case PRAGMA_OMP_CLAUSE_NOTINBRANCH:
          clauses = c_parser_omp_clause_branch (parser, OMP_CLAUSE_NOTINBRANCH,
                                                clauses);
          c_name = "notinbranch";
          break;
        case PRAGMA_OMP_CLAUSE_PARALLEL:
          clauses
            = c_parser_omp_clause_cancelkind (parser, OMP_CLAUSE_PARALLEL,
                                              clauses);
          c_name = "parallel";
          if (!first)
            {
             clause_not_first:
              error_at (here, "%qs must be the first clause of %qs",
                        c_name, where);
              clauses = prev;
            }
          break;
        case PRAGMA_OMP_CLAUSE_FOR:
          clauses
            = c_parser_omp_clause_cancelkind (parser, OMP_CLAUSE_FOR,
                                              clauses);
          c_name = "for";
          if (!first)
            goto clause_not_first;
          break;
        case PRAGMA_OMP_CLAUSE_SECTIONS:
          clauses
            = c_parser_omp_clause_cancelkind (parser, OMP_CLAUSE_SECTIONS,
                                              clauses);
          c_name = "sections";
          if (!first)
            goto clause_not_first;
          break;
        case PRAGMA_OMP_CLAUSE_TASKGROUP:
          clauses
            = c_parser_omp_clause_cancelkind (parser, OMP_CLAUSE_TASKGROUP,
                                              clauses);
          c_name = "taskgroup";
          if (!first)
            goto clause_not_first;
          break;
        case PRAGMA_OMP_CLAUSE_LINK:
          clauses
            = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_LINK, clauses);
          c_name = "link";
          break;
        case PRAGMA_OMP_CLAUSE_TO:
          if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINK)) != 0)
            {
              tree nl = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ENTER,
                                                      clauses);
              for (tree c = nl; c != clauses; c = OMP_CLAUSE_CHAIN (c))
                OMP_CLAUSE_ENTER_TO (c) = 1;
              clauses = nl;
            }
          else
            clauses = c_parser_omp_clause_from_to (parser, OMP_CLAUSE_TO,
                                                   clauses);
          c_name = "to";
          break;
        case PRAGMA_OMP_CLAUSE_FROM:
          clauses = c_parser_omp_clause_from_to (parser, OMP_CLAUSE_FROM,
                                                 clauses);
          c_name = "from";
          break;
        case PRAGMA_OMP_CLAUSE_UNIFORM:
          clauses = c_parser_omp_clause_uniform (parser, clauses);
          c_name = "uniform";
          break;
        case PRAGMA_OMP_CLAUSE_NUM_TEAMS:
          clauses = c_parser_omp_clause_num_teams (parser, clauses);
          c_name = "num_teams";
          break;
        case PRAGMA_OMP_CLAUSE_THREAD_LIMIT:
          clauses = c_parser_omp_clause_thread_limit (parser, clauses);
          c_name = "thread_limit";
          break;
        case PRAGMA_OMP_CLAUSE_ALIGNED:
          clauses = c_parser_omp_clause_aligned (parser, clauses);
          c_name = "aligned";
          break;
        case PRAGMA_OMP_CLAUSE_ALLOCATE:
          clauses = c_parser_omp_clause_allocate (parser, clauses);
          c_name = "allocate";
          break;
        case PRAGMA_OMP_CLAUSE_LINEAR: 
          clauses = c_parser_omp_clause_linear (parser, clauses); 
          c_name = "linear";
          break;
        case PRAGMA_OMP_CLAUSE_AFFINITY:
          clauses = c_parser_omp_clause_affinity (parser, clauses);
          c_name = "affinity";
          break;
        case PRAGMA_OMP_CLAUSE_DEPEND:
          clauses = c_parser_omp_clause_depend (parser, clauses);
          c_name = "depend";
          break;
        case PRAGMA_OMP_CLAUSE_DOACROSS:
          clauses = c_parser_omp_clause_doacross (parser, clauses);
          c_name = "doacross";
          break;
        case PRAGMA_OMP_CLAUSE_MAP:
          clauses = c_parser_omp_clause_map (parser, clauses);
          c_name = "map";
          break;
        case PRAGMA_OMP_CLAUSE_USE_DEVICE_PTR:
          clauses = c_parser_omp_clause_use_device_ptr (parser, clauses);
          c_name = "use_device_ptr";
          break;
        case PRAGMA_OMP_CLAUSE_USE_DEVICE_ADDR:
          clauses = c_parser_omp_clause_use_device_addr (parser, clauses);
          c_name = "use_device_addr";
          break;
        case PRAGMA_OMP_CLAUSE_HAS_DEVICE_ADDR:
          clauses = c_parser_omp_clause_has_device_addr (parser, clauses);
          c_name = "has_device_addr";
          break;
        case PRAGMA_OMP_CLAUSE_IS_DEVICE_PTR:
          clauses = c_parser_omp_clause_is_device_ptr (parser, clauses);
          c_name = "is_device_ptr";
          break;
        case PRAGMA_OMP_CLAUSE_DEVICE:
          clauses = c_parser_omp_clause_device (parser, clauses);
          c_name = "device";
          break;
        case PRAGMA_OMP_CLAUSE_DIST_SCHEDULE:
          clauses = c_parser_omp_clause_dist_schedule (parser, clauses);
          c_name = "dist_schedule";
          break;
        case PRAGMA_OMP_CLAUSE_PROC_BIND:
          clauses = c_parser_omp_clause_proc_bind (parser, clauses);
          c_name = "proc_bind";
          break;
        case PRAGMA_OMP_CLAUSE_DEVICE_TYPE:
          clauses = c_parser_omp_clause_device_type (parser, clauses);
          c_name = "device_type";
          break;
        case PRAGMA_OMP_CLAUSE_SAFELEN:
          clauses = c_parser_omp_clause_safelen (parser, clauses);
          c_name = "safelen";
          break;
        case PRAGMA_OMP_CLAUSE_SIMDLEN:
          clauses = c_parser_omp_clause_simdlen (parser, clauses);
          c_name = "simdlen";
          break;
        case PRAGMA_OMP_CLAUSE_NOGROUP:
          clauses = c_parser_omp_clause_nogroup (parser, clauses);
          c_name = "nogroup";
          break;
        case PRAGMA_OMP_CLAUSE_THREADS:
          clauses
            = c_parser_omp_clause_orderedkind (parser, OMP_CLAUSE_THREADS,
                                               clauses);
          c_name = "threads";
          break;
        case PRAGMA_OMP_CLAUSE_SIMD:
          clauses
            = c_parser_omp_clause_orderedkind (parser, OMP_CLAUSE_SIMD,
                                               clauses);
          c_name = "simd";
          break;
        case PRAGMA_OMP_CLAUSE_ENTER:
          clauses
            = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ENTER,
                                            clauses);
          c_name = "enter";
          break;
        default:
          c_parser_error (parser, "expected an OpenMP clause");
          goto saw_error;
        }

      first = false;

      if (((mask >> c_kind) & 1) == 0)
        {
          /* Remove the invalid clause(s) from the list to avoid
             confusing the rest of the compiler.  */
          clauses = prev;
          error_at (here, "%qs is not valid for %qs", c_name, where);
        }
    }

 saw_error:
  if (!nested)
    c_parser_skip_to_pragma_eol (parser);

  if (finish_p)
    {
      if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_UNIFORM)) != 0)
        return c_finish_omp_clauses (clauses, C_ORT_OMP_DECLARE_SIMD);
      return c_finish_omp_clauses (clauses, C_ORT_OMP);
    }

  return clauses;
}

/* OpenACC 2.0, OpenMP 2.5:
   structured-block:
     statement

   In practice, we're also interested in adding the statement to an
   outer node.  So it is convenient if we work around the fact that
   c_parser_statement calls add_stmt.  */

static tree
c_parser_omp_structured_block (c_parser *parser, bool *if_p)
{
  tree stmt = push_stmt_list ();
  parser->omp_attrs_forbidden_p = true;
  c_parser_statement (parser, if_p);
  return pop_stmt_list (stmt);
}

/* OpenACC 2.0:
   # pragma acc cache (variable-list) new-line

   LOC is the location of the #pragma token.
*/

static tree
c_parser_oacc_cache (location_t loc, c_parser *parser)
{
  tree stmt, clauses;

  clauses = c_parser_omp_var_list_parens (parser, OMP_CLAUSE__CACHE_, NULL);
  clauses = c_finish_omp_clauses (clauses, C_ORT_ACC);

  c_parser_skip_to_pragma_eol (parser);

  stmt = make_node (OACC_CACHE);
  TREE_TYPE (stmt) = void_type_node;
  OACC_CACHE_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);

  return stmt;
}

/* OpenACC 2.0:
   # pragma acc data oacc-data-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma token.
*/

#define OACC_DATA_CLAUSE_MASK                                           \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ATTACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPY)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEFAULT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICEPTR)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NO_CREATE)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRESENT))

static tree
c_parser_oacc_data (location_t loc, c_parser *parser, bool *if_p)
{
  tree stmt, clauses, block;

  clauses = c_parser_oacc_all_clauses (parser, OACC_DATA_CLAUSE_MASK,
                                       "#pragma acc data");

  block = c_begin_omp_parallel ();
  add_stmt (c_parser_omp_structured_block (parser, if_p));

  stmt = c_finish_oacc_data (loc, clauses, block);

  return stmt;
}

/* OpenACC 2.0:
   # pragma acc declare oacc-data-clause[optseq] new-line
*/

#define OACC_DECLARE_CLAUSE_MASK                                        \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPY)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICEPTR)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICE_RESIDENT)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_LINK)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRESENT))

static void
c_parser_oacc_declare (c_parser *parser)
{
  location_t pragma_loc = c_parser_peek_token (parser)->location;
  tree clauses, stmt, t, decl;

  bool error = false;

  c_parser_consume_pragma (parser);

  clauses = c_parser_oacc_all_clauses (parser, OACC_DECLARE_CLAUSE_MASK,
                                       "#pragma acc declare");
  if (!clauses)
    {
      error_at (pragma_loc,
                "no valid clauses specified in %<#pragma acc declare%>");
      return;
    }

  for (t = clauses; t; t = OMP_CLAUSE_CHAIN (t))
    {
      location_t loc = OMP_CLAUSE_LOCATION (t);
      decl = OMP_CLAUSE_DECL (t);
      if (!DECL_P (decl))
        {
          error_at (loc, "array section in %<#pragma acc declare%>");
          error = true;
          continue;
        }

      switch (OMP_CLAUSE_MAP_KIND (t))
        {
        case GOMP_MAP_FIRSTPRIVATE_POINTER:
        case GOMP_MAP_ALLOC:
        case GOMP_MAP_TO:
        case GOMP_MAP_FORCE_DEVICEPTR:
        case GOMP_MAP_DEVICE_RESIDENT:
          break;

        case GOMP_MAP_LINK:
          if (!global_bindings_p ()
              && (TREE_STATIC (decl)
               || !DECL_EXTERNAL (decl)))
            {
              error_at (loc,
                        "%qD must be a global variable in "
                        "%<#pragma acc declare link%>",
                        decl);
              error = true;
              continue;
            }
          break;

        default:
          if (global_bindings_p ())
            {
              error_at (loc, "invalid OpenACC clause at file scope");
              error = true;
              continue;
            }
          if (DECL_EXTERNAL (decl))
            {
              error_at (loc,
                        "invalid use of %<extern%> variable %qD "
                        "in %<#pragma acc declare%>", decl);
              error = true;
              continue;
            }
          else if (TREE_PUBLIC (decl))
            {
              error_at (loc,
                        "invalid use of %<global%> variable %qD "
                        "in %<#pragma acc declare%>", decl);
              error = true;
              continue;
            }
          break;
        }

      if (!c_check_in_current_scope (decl))
        {
          error_at (loc,
                    "%qD must be a variable declared in the same scope as "
                    "%<#pragma acc declare%>", decl);
          error = true;
          continue;
        }

      if (lookup_attribute ("omp declare target", DECL_ATTRIBUTES (decl))
          || lookup_attribute ("omp declare target link",
                               DECL_ATTRIBUTES (decl)))
        {
          error_at (loc, "variable %qD used more than once with "
                    "%<#pragma acc declare%>", decl);
          error = true;
          continue;
        }

      if (!error)
        {
          tree id;

          if (OMP_CLAUSE_MAP_KIND (t) == GOMP_MAP_LINK)
            id = get_identifier ("omp declare target link");
          else
            id = get_identifier ("omp declare target");

          DECL_ATTRIBUTES (decl)
                           = tree_cons (id, NULL_TREE, DECL_ATTRIBUTES (decl));

          if (global_bindings_p ())
            {
              symtab_node *node = symtab_node::get (decl);
              if (node != NULL)
                {
                  node->offloadable = 1;
                  if (ENABLE_OFFLOADING)
                    {
                      g->have_offload = true;
                      if (is_a <varpool_node *> (node))
                        vec_safe_push (offload_vars, decl);
                    }
                }
            }
        }
    }

  if (error || global_bindings_p ())
    return;

  stmt = make_node (OACC_DECLARE);
  TREE_TYPE (stmt) = void_type_node;
  OACC_DECLARE_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, pragma_loc);

  add_stmt (stmt);

  return;
}

/* OpenACC 2.0:
   # pragma acc enter data oacc-enter-data-clause[optseq] new-line

   or

   # pragma acc exit data oacc-exit-data-clause[optseq] new-line


   LOC is the location of the #pragma token.
*/

#define OACC_ENTER_DATA_CLAUSE_MASK                                     \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ATTACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

#define OACC_EXIT_DATA_CLAUSE_MASK                                      \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DELETE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DETACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_FINALIZE)            \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

static void
c_parser_oacc_enter_exit_data (c_parser *parser, bool enter)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree clauses, stmt;
  const char *p = "";

  c_parser_consume_pragma (parser);

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      c_parser_consume_token (parser);
    }

  if (strcmp (p, "data") != 0)
    {
      error_at (loc, "expected %<data%> after %<#pragma acc %s%>",
                enter ? "enter" : "exit");
      parser->error = true;
      c_parser_skip_to_pragma_eol (parser);
      return;
    }

  if (enter)
    clauses = c_parser_oacc_all_clauses (parser, OACC_ENTER_DATA_CLAUSE_MASK,
                                         "#pragma acc enter data");
  else
    clauses = c_parser_oacc_all_clauses (parser, OACC_EXIT_DATA_CLAUSE_MASK,
                                         "#pragma acc exit data");

  if (omp_find_clause (clauses, OMP_CLAUSE_MAP) == NULL_TREE)
    {
      error_at (loc, "%<#pragma acc %s data%> has no data movement clause",
                enter ? "enter" : "exit");
      return;
    }

  stmt = enter ? make_node (OACC_ENTER_DATA) : make_node (OACC_EXIT_DATA);
  TREE_TYPE (stmt) = void_type_node;
  OMP_STANDALONE_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
}


/* OpenACC 2.0:
   # pragma acc host_data oacc-data-clause[optseq] new-line
     structured-block
*/

#define OACC_HOST_DATA_CLAUSE_MASK                                      \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_USE_DEVICE)          \
         | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
         | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF_PRESENT) )

static tree
c_parser_oacc_host_data (location_t loc, c_parser *parser, bool *if_p)
{
  tree stmt, clauses, block;

  clauses = c_parser_oacc_all_clauses (parser, OACC_HOST_DATA_CLAUSE_MASK,
                                       "#pragma acc host_data", false);
  if (!omp_find_clause (clauses, OMP_CLAUSE_USE_DEVICE_PTR))
    {
      error_at (loc, "%<host_data%> construct requires %<use_device%> clause");
      return error_mark_node;
    }
  clauses = c_finish_omp_clauses (clauses, C_ORT_ACC);
  block = c_begin_omp_parallel ();
  add_stmt (c_parser_omp_structured_block (parser, if_p));
  stmt = c_finish_oacc_host_data (loc, clauses, block);
  return stmt;
}


/* OpenACC 2.0:

   # pragma acc loop oacc-loop-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma token.
*/

#define OACC_LOOP_CLAUSE_MASK                                           \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COLLAPSE)            \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRIVATE)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_REDUCTION)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_GANG)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WORKER)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_VECTOR)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_AUTO)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_INDEPENDENT)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SEQ)                 \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_TILE) )
static tree
c_parser_oacc_loop (location_t loc, c_parser *parser, char *p_name,
                    omp_clause_mask mask, tree *cclauses, bool *if_p)
{
  bool is_parallel = ((mask >> PRAGMA_OACC_CLAUSE_REDUCTION) & 1) == 1;

  strcat (p_name, " loop");
  mask |= OACC_LOOP_CLAUSE_MASK;

  tree clauses = c_parser_oacc_all_clauses (parser, mask, p_name,
                                            /*finish_p=*/cclauses == NULL,
                                            /*target=*/is_parallel);
  if (cclauses)
    {
      clauses = c_oacc_split_loop_clauses (clauses, cclauses, is_parallel);
      if (*cclauses)
        *cclauses = c_finish_omp_clauses (*cclauses, C_ORT_ACC_TARGET);
      if (clauses)
        clauses = c_finish_omp_clauses (clauses, C_ORT_ACC);
    }

  tree block = c_begin_compound_stmt (true);
  tree stmt = c_parser_omp_for_loop (loc, parser, OACC_LOOP, clauses, NULL,
                                     if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return stmt;
}

/* OpenACC 2.0:
   # pragma acc kernels oacc-kernels-clause[optseq] new-line
     structured-block

   or

   # pragma acc parallel oacc-parallel-clause[optseq] new-line
     structured-block

   OpenACC 2.6:

   # pragma acc serial oacc-serial-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma token.
*/

#define OACC_KERNELS_CLAUSE_MASK                                        \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ATTACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPY)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEFAULT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICEPTR)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NO_CREATE)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NUM_GANGS)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NUM_WORKERS)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRESENT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SELF)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_VECTOR_LENGTH)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

#define OACC_PARALLEL_CLAUSE_MASK                                       \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ATTACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPY)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEFAULT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICEPTR)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NO_CREATE)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRIVATE)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_FIRSTPRIVATE)        \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NUM_GANGS)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NUM_WORKERS)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRESENT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_REDUCTION)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SELF)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_VECTOR_LENGTH)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

#define OACC_SERIAL_CLAUSE_MASK                                 \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ATTACH)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPY)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYIN)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_COPYOUT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_CREATE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEFAULT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICEPTR)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NO_CREATE)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRIVATE)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_FIRSTPRIVATE)        \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_PRESENT)             \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_REDUCTION)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SELF)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

static tree
c_parser_oacc_compute (location_t loc, c_parser *parser,
                       enum pragma_kind p_kind, char *p_name, bool *if_p)
{
  omp_clause_mask mask;
  enum tree_code code;
  switch (p_kind)
    {
    case PRAGMA_OACC_KERNELS:
      strcat (p_name, " kernels");
      mask = OACC_KERNELS_CLAUSE_MASK;
      code = OACC_KERNELS;
      break;
    case PRAGMA_OACC_PARALLEL:
      strcat (p_name, " parallel");
      mask = OACC_PARALLEL_CLAUSE_MASK;
      code = OACC_PARALLEL;
      break;
    case PRAGMA_OACC_SERIAL:
      strcat (p_name, " serial");
      mask = OACC_SERIAL_CLAUSE_MASK;
      code = OACC_SERIAL;
      break;
    default:
      gcc_unreachable ();
    }

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "loop") == 0)
        {
          c_parser_consume_token (parser);
          tree block = c_begin_omp_parallel ();
          tree clauses;
          c_parser_oacc_loop (loc, parser, p_name, mask, &clauses, if_p);
          return c_finish_omp_construct (loc, code, block, clauses);
        }
    }

  tree clauses = c_parser_oacc_all_clauses (parser, mask, p_name,
                                            /*finish_p=*/true,
                                            /*target=*/true);

  tree block = c_begin_omp_parallel ();
  add_stmt (c_parser_omp_structured_block (parser, if_p));

  return c_finish_omp_construct (loc, code, block, clauses);
}

/* OpenACC 2.0:
   # pragma acc routine oacc-routine-clause[optseq] new-line
     function-definition

   # pragma acc routine ( name ) oacc-routine-clause[optseq] new-line
*/

#define OACC_ROUTINE_CLAUSE_MASK                                        \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_GANG)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WORKER)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_VECTOR)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SEQ)                 \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_NOHOST) )

/* Parse an OpenACC routine directive.  For named directives, we apply
   immediately to the named function.  For unnamed ones we then parse
   a declaration or definition, which must be for a function.  */

static void
c_parser_oacc_routine (c_parser *parser, enum pragma_context context)
{
  gcc_checking_assert (context == pragma_external);

  oacc_routine_data data;
  data.error_seen = false;
  data.fndecl_seen = false;
  data.loc = c_parser_peek_token (parser)->location;

  c_parser_consume_pragma (parser);

  /* Look for optional '( name )'.  */
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      c_parser_consume_token (parser); /* '(' */

      tree decl = NULL_TREE;
      c_token *name_token = c_parser_peek_token (parser);
      location_t name_loc = name_token->location;
      if (name_token->type == CPP_NAME
          && (name_token->id_kind == C_ID_ID
              || name_token->id_kind == C_ID_TYPENAME))
        {
          decl = lookup_name (name_token->value);
          if (!decl)
            error_at (name_loc,
                      "%qE has not been declared", name_token->value);
          c_parser_consume_token (parser);
        }
      else
        c_parser_error (parser, "expected function name");

      if (!decl
          || !c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
        {
          c_parser_skip_to_pragma_eol (parser, false);
          return;
        }

      data.clauses
        = c_parser_oacc_all_clauses (parser, OACC_ROUTINE_CLAUSE_MASK,
                                     "#pragma acc routine");
      /* The clauses are in reverse order; fix that to make later diagnostic
         emission easier.  */
      data.clauses = nreverse (data.clauses);

      if (TREE_CODE (decl) != FUNCTION_DECL)
        {
          error_at (name_loc, "%qD does not refer to a function", decl);
          return;
        }

      c_finish_oacc_routine (&data, decl, false);
    }
  else /* No optional '( name )'.  */
    {
      data.clauses
        = c_parser_oacc_all_clauses (parser, OACC_ROUTINE_CLAUSE_MASK,
                                     "#pragma acc routine");
      /* The clauses are in reverse order; fix that to make later diagnostic
         emission easier.  */
      data.clauses = nreverse (data.clauses);

      /* Emit a helpful diagnostic if there's another pragma following this
         one.  Also don't allow a static assertion declaration, as in the
         following we'll just parse a *single* "declaration or function
         definition", and the static assertion counts an one.  */
      if (c_parser_next_token_is (parser, CPP_PRAGMA)
          || c_parser_next_token_is_keyword (parser, RID_STATIC_ASSERT))
        {
          error_at (data.loc,
                    "%<#pragma acc routine%> not immediately followed by"
                    " function declaration or definition");
          /* ..., and then just keep going.  */
          return;
        }

      /* We only have to consider the pragma_external case here.  */
      if (c_parser_next_token_is (parser, CPP_KEYWORD)
          && c_parser_peek_token (parser)->keyword == RID_EXTENSION)
        {
          int ext = disable_extension_diagnostics ();
          do
            c_parser_consume_token (parser);
          while (c_parser_next_token_is (parser, CPP_KEYWORD)
                 && c_parser_peek_token (parser)->keyword == RID_EXTENSION);
          c_parser_declaration_or_fndef (parser, true, true, true, false, true,
                                         NULL, NULL, false, NULL, &data);
          restore_extension_diagnostics (ext);
        }
      else
        c_parser_declaration_or_fndef (parser, true, true, true, false, true,
                                       NULL, NULL, false, NULL, &data);
    }
}

/* Finalize an OpenACC routine pragma, applying it to FNDECL.
   IS_DEFN is true if we're applying it to the definition.  */

static void
c_finish_oacc_routine (struct oacc_routine_data *data, tree fndecl,
                       bool is_defn)
{
  /* Keep going if we're in error reporting mode.  */
  if (data->error_seen
      || fndecl == error_mark_node)
    return;

  if (data->fndecl_seen)
    {
      error_at (data->loc,
                "%<#pragma acc routine%> not immediately followed by"
                " a single function declaration or definition");
      data->error_seen = true;
      return;
    }
  if (fndecl == NULL_TREE || TREE_CODE (fndecl) != FUNCTION_DECL)
    {
      error_at (data->loc,
                "%<#pragma acc routine%> not immediately followed by"
                " function declaration or definition");
      data->error_seen = true;
      return;
    }

  int compatible
    = oacc_verify_routine_clauses (fndecl, &data->clauses, data->loc,
                                   "#pragma acc routine");
  if (compatible < 0)
    {
      data->error_seen = true;
      return;
    }
  if (compatible > 0)
    {
    }
  else
    {
      if (TREE_USED (fndecl) || (!is_defn && DECL_SAVED_TREE (fndecl)))
        {
          error_at (data->loc,
                    TREE_USED (fndecl)
                    ? G_("%<#pragma acc routine%> must be applied before use")
                    : G_("%<#pragma acc routine%> must be applied before"
                         " definition"));
          data->error_seen = true;
          return;
        }

      /* Set the routine's level of parallelism.  */
      tree dims = oacc_build_routine_dims (data->clauses);
      oacc_replace_fn_attrib (fndecl, dims);

      /* Add an "omp declare target" attribute.  */
      DECL_ATTRIBUTES (fndecl)
        = tree_cons (get_identifier ("omp declare target"),
                     data->clauses, DECL_ATTRIBUTES (fndecl));
    }

  /* Remember that we've used this "#pragma acc routine".  */
  data->fndecl_seen = true;
}

/* OpenACC 2.0:
   # pragma acc update oacc-update-clause[optseq] new-line
*/

#define OACC_UPDATE_CLAUSE_MASK                                         \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_DEVICE)              \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_HOST)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF)                  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_IF_PRESENT)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_SELF)                \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_WAIT) )

static void
c_parser_oacc_update (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;

  c_parser_consume_pragma (parser);

  tree clauses = c_parser_oacc_all_clauses (parser, OACC_UPDATE_CLAUSE_MASK,
                                            "#pragma acc update");
  if (omp_find_clause (clauses, OMP_CLAUSE_MAP) == NULL_TREE)
    {
      error_at (loc,
                "%<#pragma acc update%> must contain at least one "
                "%<device%> or %<host%> or %<self%> clause");
      return;
    }

  if (parser->error)
    return;

  tree stmt = make_node (OACC_UPDATE);
  TREE_TYPE (stmt) = void_type_node;
  OACC_UPDATE_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
}

/* OpenACC 2.0:
   # pragma acc wait [(intseq)] oacc-wait-clause[optseq] new-line

   LOC is the location of the #pragma token.
*/

#define OACC_WAIT_CLAUSE_MASK                                           \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OACC_CLAUSE_ASYNC) )

static tree
c_parser_oacc_wait (location_t loc, c_parser *parser, char *p_name)
{
  tree clauses, list = NULL_TREE, stmt = NULL_TREE;

  if (c_parser_peek_token (parser)->type == CPP_OPEN_PAREN)
    list = c_parser_oacc_wait_list (parser, loc, list);

  strcpy (p_name, " wait");
  clauses = c_parser_oacc_all_clauses (parser, OACC_WAIT_CLAUSE_MASK, p_name);
  stmt = c_finish_oacc_wait (loc, list, clauses);
  add_stmt (stmt);

  return stmt;
}

struct c_omp_loc_tree
{
  location_t loc;
  tree var;
};

/* Check whether the expression used in the allocator clause is declared or
   modified between the variable declaration and its allocate directive.  */
static tree
c_check_omp_allocate_allocator_r (tree *tp, int *, void *data)
{
  tree var = ((struct c_omp_loc_tree *) data)->var;
  location_t loc = ((struct c_omp_loc_tree *) data)->loc;
  if (TREE_CODE (*tp) == VAR_DECL && c_check_in_current_scope (*tp))
    {
      if (linemap_location_before_p (line_table, DECL_SOURCE_LOCATION (var),
                                     DECL_SOURCE_LOCATION (*tp)))
        {
          error_at (loc, "variable %qD used in the %<allocator%> clause must "
                         "be declared before %qD", *tp, var);
          inform (DECL_SOURCE_LOCATION (*tp), "declared here");
          inform (DECL_SOURCE_LOCATION (var),
                  "to be allocated variable declared here");
          return *tp;
        }
      else
        {
          gcc_assert (cur_stmt_list
                      && TREE_CODE (cur_stmt_list) == STATEMENT_LIST);

          tree_stmt_iterator l = tsi_last (cur_stmt_list);
          while (!tsi_end_p (l))
            {
              if (linemap_location_before_p (line_table, EXPR_LOCATION (*l),
                                             DECL_SOURCE_LOCATION (var)))
                  break;
              if (TREE_CODE (*l) == MODIFY_EXPR
                  && TREE_OPERAND (*l, 0) == *tp)
                {
                  error_at (loc,
                            "variable %qD used in the %<allocator%> clause "
                            "must not be modified between declaration of %qD "
                            "and its %<allocate%> directive", *tp, var);
                  inform (EXPR_LOCATION (*l), "modified here");
                  inform (DECL_SOURCE_LOCATION (var),
                          "to be allocated variable declared here");
                  return *tp;
                }
              --l;
            }
        }
    }
  return NULL_TREE;
}

/* OpenMP 5.x:
   # pragma omp allocate (list)  clauses

   OpenMP 5.0 clause:
   allocator (omp_allocator_handle_t expression)

   OpenMP 5.1 additional clause:
   align (constant-expression)]  */

static void
c_parser_omp_allocate (c_parser *parser)
{
  tree alignment = NULL_TREE;
  tree allocator = NULL_TREE;
  c_parser_consume_pragma (parser);
  location_t loc = c_parser_peek_token (parser)->location;
  location_t allocator_loc = UNKNOWN_LOCATION;
  tree nl = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ALLOCATE, NULL_TREE);
  do
    {
      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);
      if (!c_parser_next_token_is (parser, CPP_NAME))
        break;
      matching_parens parens;
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      c_parser_consume_token (parser);
      location_t expr_loc = c_parser_peek_token (parser)->location;
      if (strcmp ("align", p) != 0 && strcmp ("allocator", p) != 0)
        {
          error_at (c_parser_peek_token (parser)->location,
                    "expected %<allocator%> or %<align%>");
          break;
        }
      if (!parens.require_open (parser))
        break;

      c_expr expr = c_parser_expr_no_commas (parser, NULL);
      expr = convert_lvalue_to_rvalue (expr_loc, expr, false, true);
      expr_loc = c_parser_peek_token (parser)->location;
      if (expr.value == error_mark_node)
        ;
      else if (p[2] == 'i' && alignment)
        {
          error_at (expr_loc, "too many %qs clauses", "align");
          break;
        }
      else if (p[2] == 'i')
        {
          alignment = c_fully_fold (expr.value, false, NULL);
          if (TREE_CODE (alignment) != INTEGER_CST
              || !INTEGRAL_TYPE_P (TREE_TYPE (alignment))
              || tree_int_cst_sgn (alignment) != 1
              || !integer_pow2p (alignment))
            {
              error_at (expr_loc, "%<align%> clause argument needs to be "
                                  "positive constant power of two integer "
                                  "expression");
              alignment = NULL_TREE;
            }
        }
      else if (allocator)
        {
          error_at (expr_loc, "too many %qs clauses", "allocator");
          break;
        }
      else
        {
          allocator = c_fully_fold (expr.value, false, NULL);
          allocator_loc = expr_loc;
          tree orig_type
            = expr.original_type ? expr.original_type : TREE_TYPE (allocator);
          orig_type = TYPE_MAIN_VARIANT (orig_type);
          if (!INTEGRAL_TYPE_P (TREE_TYPE (allocator))
              || TREE_CODE (orig_type) != ENUMERAL_TYPE
              || TYPE_NAME (orig_type)
                 != get_identifier ("omp_allocator_handle_t"))
            {
              error_at (expr_loc,
                        "%<allocator%> clause allocator expression has type "
                        "%qT rather than %<omp_allocator_handle_t%>",
                        TREE_TYPE (allocator));
              allocator = NULL_TREE;
            }
        }
      parens.skip_until_found_close (parser);
    } while (true);
  c_parser_skip_to_pragma_eol (parser);

  c_mark_decl_jump_unsafe_in_current_scope ();
  for (tree c = nl; c != NULL_TREE; c = OMP_CLAUSE_CHAIN (c))
    {
      tree var = OMP_CLAUSE_DECL (c);
      if (TREE_CODE (var) == PARM_DECL)
        {
          error_at (OMP_CLAUSE_LOCATION (nl),
                    "function parameter %qD may not appear as list item in an "
                    "%<allocate%> directive", var);
          continue;
        }
      if (!c_check_in_current_scope (var))
        {
          error_at (OMP_CLAUSE_LOCATION (nl),
                    "%<allocate%> directive must be in the same scope as %qD",
                    var);
          inform (DECL_SOURCE_LOCATION (var), "declared here");
          continue;
        }
      if (lookup_attribute ("omp allocate", DECL_ATTRIBUTES (var)))
        {
          error_at (OMP_CLAUSE_LOCATION (nl),
                    "%qD already appeared as list item in an "
                    "%<allocate%> directive", var);
          continue;
        }
      if (TREE_STATIC (var))
        {
          if (allocator == NULL_TREE && allocator_loc == UNKNOWN_LOCATION)
            error_at (loc, "%<allocator%> clause required for "
                           "static variable %qD", var);
          else if (allocator
                   && (wi::to_widest (allocator) < 1
                       || wi::to_widest (allocator) > 8))
            /* 8 = largest predefined memory allocator. */
            error_at (allocator_loc,
                      "%<allocator%> clause requires a predefined allocator as "
                      "%qD is static", var);
          else
            sorry_at (OMP_CLAUSE_LOCATION (nl),
                      "%<#pragma omp allocate%> for static variables like "
                      "%qD not yet supported", var);
          continue;
        }
      if (allocator)
        {
          struct c_omp_loc_tree data
            = {EXPR_LOC_OR_LOC (allocator, OMP_CLAUSE_LOCATION (nl)), var};
          walk_tree (&allocator, c_check_omp_allocate_allocator_r, &data, NULL);
        }
      DECL_ATTRIBUTES (var) = tree_cons (get_identifier ("omp allocate"),
                                         build_tree_list (allocator, alignment),
                                         DECL_ATTRIBUTES (var));
    }
}

/* OpenMP 2.5:
   # pragma omp atomic new-line
     expression-stmt

   expression-stmt:
     x binop= expr | x++ | ++x | x-- | --x
   binop:
     +, *, -, /, &, ^, |, <<, >>

  where x is an lvalue expression with scalar type.

   OpenMP 3.1:
   # pragma omp atomic new-line
     update-stmt

   # pragma omp atomic read new-line
     read-stmt

   # pragma omp atomic write new-line
     write-stmt

   # pragma omp atomic update new-line
     update-stmt

   # pragma omp atomic capture new-line
     capture-stmt

   # pragma omp atomic capture new-line
     capture-block

   read-stmt:
     v = x
   write-stmt:
     x = expr
   update-stmt:
     expression-stmt | x = x binop expr
   capture-stmt:
     v = expression-stmt
   capture-block:
     { v = x; update-stmt; } | { update-stmt; v = x; }

   OpenMP 4.0:
   update-stmt:
     expression-stmt | x = x binop expr | x = expr binop x
   capture-stmt:
     v = update-stmt
   capture-block:
     { v = x; update-stmt; } | { update-stmt; v = x; } | { v = x; x = expr; }

   OpenMP 5.1:
   # pragma omp atomic compare new-line
     conditional-update-atomic

   # pragma omp atomic compare capture new-line
     conditional-update-capture-atomic

   conditional-update-atomic:
     cond-expr-stmt | cond-update-stmt
   cond-expr-stmt:
     x = expr ordop x ? expr : x;
     x = x ordop expr ? expr : x;
     x = x == e ? d : x;
   cond-update-stmt:
     if (expr ordop x) { x = expr; }
     if (x ordop expr) { x = expr; }
     if (x == e) { x = d; }
   ordop:
     <, >
   conditional-update-capture-atomic:
     v = cond-expr-stmt
     { v = x; cond-expr-stmt }
     { cond-expr-stmt v = x; }
     { v = x; cond-update-stmt }
     { cond-update-stmt v = x; }
     if (x == e) { x = d; } else { v = x; }
     { r = x == e; if (r) { x = d; } }
     { r = x == e; if (r) { x = d; } else { v = x; } }

  where x, r and v are lvalue expressions with scalar type,
  expr, e and d are expressions with scalar type and e might be
  the same as v.

  LOC is the location of the #pragma token.  */

static void
c_parser_omp_atomic (location_t loc, c_parser *parser, bool openacc)
{
  tree lhs = NULL_TREE, rhs = NULL_TREE, v = NULL_TREE, r = NULL_TREE;
  tree lhs1 = NULL_TREE, rhs1 = NULL_TREE;
  tree stmt, orig_lhs, unfolded_lhs = NULL_TREE, unfolded_lhs1 = NULL_TREE;
  enum tree_code code = ERROR_MARK, opcode = NOP_EXPR;
  enum omp_memory_order memory_order = OMP_MEMORY_ORDER_UNSPECIFIED;
  struct c_expr expr;
  location_t eloc;
  bool structured_block = false;
  bool swapped = false;
  bool non_lvalue_p;
  tree clauses = NULL_TREE;
  bool capture = false;
  bool compare = false;
  bool weak = false;
  enum omp_memory_order fail = OMP_MEMORY_ORDER_UNSPECIFIED;
  bool no_semicolon = false;
  bool extra_scope = false;

  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);

      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          const char *p
            = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
          location_t cloc = c_parser_peek_token (parser)->location;
          enum tree_code new_code = ERROR_MARK;
          enum omp_memory_order new_memory_order
            = OMP_MEMORY_ORDER_UNSPECIFIED;
          bool new_capture = false;
          bool new_compare = false;
          bool new_weak = false;
          enum omp_memory_order new_fail = OMP_MEMORY_ORDER_UNSPECIFIED;

          if (!strcmp (p, "read"))
            new_code = OMP_ATOMIC_READ;
          else if (!strcmp (p, "write"))
            new_code = NOP_EXPR;
          else if (!strcmp (p, "update"))
            new_code = OMP_ATOMIC;
          else if (openacc && !strcmp (p, "capture"))
            new_code = OMP_ATOMIC_CAPTURE_NEW;
          else if (openacc)
            {
              p = NULL;
              error_at (cloc, "expected %<read%>, %<write%>, %<update%>, "
                              "or %<capture%> clause");
            }
          else if (!strcmp (p, "capture"))
            new_capture = true;
          else if (!strcmp (p, "compare"))
            new_compare = true;
          else if (!strcmp (p, "weak"))
            new_weak = true;
          else if (!strcmp (p, "fail"))
            {
              matching_parens parens;

              c_parser_consume_token (parser);
              if (!parens.require_open (parser))
                continue;

              if (c_parser_next_token_is (parser, CPP_NAME))
                {
                  const char *q
                    = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

                  if (!strcmp (q, "seq_cst"))
                    new_fail = OMP_MEMORY_ORDER_SEQ_CST;
                  else if (!strcmp (q, "acquire"))
                    new_fail = OMP_MEMORY_ORDER_ACQUIRE;
                  else if (!strcmp (q, "relaxed"))
                    new_fail = OMP_MEMORY_ORDER_RELAXED;
                }

              if (new_fail != OMP_MEMORY_ORDER_UNSPECIFIED)
                {
                  c_parser_consume_token (parser);
                  if (fail != OMP_MEMORY_ORDER_UNSPECIFIED)
                    error_at (cloc, "too many %qs clauses", "fail");
                  else
                    fail = new_fail;
                }
              else
                c_parser_error (parser, "expected %<seq_cst%>, %<acquire%> "
                                        "or %<relaxed%>");
              parens.skip_until_found_close (parser);
              continue;
            }
          else if (!strcmp (p, "seq_cst"))
            new_memory_order = OMP_MEMORY_ORDER_SEQ_CST;
          else if (!strcmp (p, "acq_rel"))
            new_memory_order = OMP_MEMORY_ORDER_ACQ_REL;
          else if (!strcmp (p, "release"))
            new_memory_order = OMP_MEMORY_ORDER_RELEASE;
          else if (!strcmp (p, "acquire"))
            new_memory_order = OMP_MEMORY_ORDER_ACQUIRE;
          else if (!strcmp (p, "relaxed"))
            new_memory_order = OMP_MEMORY_ORDER_RELAXED;
          else if (!strcmp (p, "hint"))
            {
              c_parser_consume_token (parser);
              clauses = c_parser_omp_clause_hint (parser, clauses);
              continue;
            }
          else
            {
              p = NULL;
              error_at (cloc, "expected %<read%>, %<write%>, %<update%>, "
                              "%<capture%>, %<compare%>, %<weak%>, %<fail%>, "
                              "%<seq_cst%>, %<acq_rel%>, %<release%>, "
                              "%<relaxed%> or %<hint%> clause");
            }
          if (p)
            {
              if (new_code != ERROR_MARK)
                {
                  /* OpenACC permits 'update capture'.  */
                  if (openacc
                      && code == OMP_ATOMIC
                      && new_code == OMP_ATOMIC_CAPTURE_NEW)
                    code = new_code;
                  else if (code != ERROR_MARK)
                    error_at (cloc, "too many atomic clauses");
                  else
                    code = new_code;
                }
              else if (new_memory_order != OMP_MEMORY_ORDER_UNSPECIFIED)
                {
                  if (memory_order != OMP_MEMORY_ORDER_UNSPECIFIED)
                    error_at (cloc, "too many memory order clauses");
                  else
                    memory_order = new_memory_order;
                }
              else if (new_capture)
                {
                  if (capture)
                    error_at (cloc, "too many %qs clauses", "capture");
                  else
                    capture = true;
                }
              else if (new_compare)
                {
                  if (compare)
                    error_at (cloc, "too many %qs clauses", "compare");
                  else
                    compare = true;
                }
              else if (new_weak)
                {
                  if (weak)
                    error_at (cloc, "too many %qs clauses", "weak");
                  else
                    weak = true;
                }
              c_parser_consume_token (parser);
              continue;
            }
        }
      break;
    }
  c_parser_skip_to_pragma_eol (parser);

  if (code == ERROR_MARK)
    code = OMP_ATOMIC;
  if (capture)
    {
      if (code != OMP_ATOMIC)
        error_at (loc, "%qs clause is incompatible with %<read%> or %<write%> "
                       "clauses", "capture");
      else
        code = OMP_ATOMIC_CAPTURE_NEW;
    }
  if (compare && code != OMP_ATOMIC && code != OMP_ATOMIC_CAPTURE_NEW)
    {
      error_at (loc, "%qs clause is incompatible with %<read%> or %<write%> "
                      "clauses", "compare");
      compare = false;
    }
  if (fail != OMP_MEMORY_ORDER_UNSPECIFIED && !compare)
    {
      error_at (loc, "%qs clause requires %qs clause", "fail", "compare");
      fail = OMP_MEMORY_ORDER_UNSPECIFIED;
    }
  if (weak && !compare)
    {
      error_at (loc, "%qs clause requires %qs clause", "weak", "compare");
      weak = false;
    }
  if (openacc)
    memory_order = OMP_MEMORY_ORDER_RELAXED;
  else if (memory_order == OMP_MEMORY_ORDER_UNSPECIFIED)
    {
      omp_requires_mask
        = (enum omp_requires) (omp_requires_mask
                               | OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER_USED);
      switch ((enum omp_memory_order)
              (omp_requires_mask & OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER))
        {
        case OMP_MEMORY_ORDER_UNSPECIFIED:
        case OMP_MEMORY_ORDER_RELAXED:
          memory_order = OMP_MEMORY_ORDER_RELAXED;
          break;
        case OMP_MEMORY_ORDER_SEQ_CST:
          memory_order = OMP_MEMORY_ORDER_SEQ_CST;
          break;
        case OMP_MEMORY_ORDER_ACQUIRE:
          if (code == NOP_EXPR)  /* atomic write */
            {
              error_at (loc, "%<#pragma omp atomic write%> incompatible with "
                             "%<acquire%> clause implicitly provided by a "
                             "%<requires%> directive");
              memory_order = OMP_MEMORY_ORDER_SEQ_CST;
            }
          else
            memory_order = OMP_MEMORY_ORDER_ACQUIRE;
          break;
        case OMP_MEMORY_ORDER_RELEASE:
          if (code == OMP_ATOMIC_READ)
            {
              error_at (loc, "%<#pragma omp atomic read%> incompatible with "
                             "%<release%> clause implicitly provided by a "
                             "%<requires%> directive");
              memory_order = OMP_MEMORY_ORDER_SEQ_CST;
            }
          else
            memory_order = OMP_MEMORY_ORDER_RELEASE;
          break;
        case OMP_MEMORY_ORDER_ACQ_REL:
          switch (code)
            {
            case OMP_ATOMIC_READ:
              memory_order = OMP_MEMORY_ORDER_ACQUIRE;
              break;
            case NOP_EXPR: /* atomic write */
              memory_order = OMP_MEMORY_ORDER_RELEASE;
              break;
            default:
              memory_order = OMP_MEMORY_ORDER_ACQ_REL;
              break;
            }
          break;
        default:
          gcc_unreachable ();
        }
    }
  else
    switch (code)
      {
      case OMP_ATOMIC_READ:
        if (memory_order == OMP_MEMORY_ORDER_RELEASE)
          {
            error_at (loc, "%<#pragma omp atomic read%> incompatible with "
                           "%<release%> clause");
            memory_order = OMP_MEMORY_ORDER_SEQ_CST;
          }
        else if (memory_order == OMP_MEMORY_ORDER_ACQ_REL)
          memory_order = OMP_MEMORY_ORDER_ACQUIRE;
        break;
      case NOP_EXPR: /* atomic write */
        if (memory_order == OMP_MEMORY_ORDER_ACQUIRE)
          {
            error_at (loc, "%<#pragma omp atomic write%> incompatible with "
                           "%<acquire%> clause");
            memory_order = OMP_MEMORY_ORDER_SEQ_CST;
          }
        else if (memory_order == OMP_MEMORY_ORDER_ACQ_REL)
          memory_order = OMP_MEMORY_ORDER_RELEASE;
        break;
      default:
        break;
      }
  if (fail != OMP_MEMORY_ORDER_UNSPECIFIED)
    memory_order
      = (enum omp_memory_order) (memory_order
                                 | (fail << OMP_FAIL_MEMORY_ORDER_SHIFT));

  switch (code)
    {
    case OMP_ATOMIC_READ:
    case NOP_EXPR: /* atomic write */
      v = c_parser_cast_expression (parser, NULL).value;
      non_lvalue_p = !lvalue_p (v);
      v = c_fully_fold (v, false, NULL, true);
      if (v == error_mark_node)
        goto saw_error;
      if (non_lvalue_p)
        v = non_lvalue (v);
      loc = c_parser_peek_token (parser)->location;
      if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
        goto saw_error;
      if (code == NOP_EXPR)
        {
          lhs = c_parser_expression (parser).value;
          lhs = c_fully_fold (lhs, false, NULL);
          if (lhs == error_mark_node)
            goto saw_error;
        }
      else
        {
          lhs = c_parser_cast_expression (parser, NULL).value;
          non_lvalue_p = !lvalue_p (lhs);
          lhs = c_fully_fold (lhs, false, NULL, true);
          if (lhs == error_mark_node)
            goto saw_error;
          if (non_lvalue_p)
            lhs = non_lvalue (lhs);
        }
      if (code == NOP_EXPR)
        {
          /* atomic write is represented by OMP_ATOMIC with NOP_EXPR
             opcode.  */
          code = OMP_ATOMIC;
          rhs = lhs;
          lhs = v;
          v = NULL_TREE;
        }
      goto done;
    case OMP_ATOMIC_CAPTURE_NEW:
      if (c_parser_next_token_is (parser, CPP_OPEN_BRACE))
        {
          c_parser_consume_token (parser);
          structured_block = true;
        }
      else if (compare
               && c_parser_next_token_is_keyword (parser, RID_IF))
        break;
      else
        {
          v = c_parser_cast_expression (parser, NULL).value;
          non_lvalue_p = !lvalue_p (v);
          v = c_fully_fold (v, false, NULL, true);
          if (v == error_mark_node)
            goto saw_error;
          if (non_lvalue_p)
            v = non_lvalue (v);
          if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
            goto saw_error;
          if (compare && c_parser_next_token_is_keyword (parser, RID_IF))
            {
              eloc = c_parser_peek_token (parser)->location;
              error_at (eloc, "expected expression");
              goto saw_error;
            }
        }
      break;
    default:
      break;
    }

  /* For structured_block case we don't know yet whether
     old or new x should be captured.  */
restart:
  if (compare && c_parser_next_token_is_keyword (parser, RID_IF))
    {
      c_parser_consume_token (parser);

      matching_parens parens;
      if (!parens.require_open (parser))
        goto saw_error;
      eloc = c_parser_peek_token (parser)->location;
      c_expr cmp_expr;
      if (r)
        {
          cmp_expr = c_parser_cast_expression (parser, NULL);
          cmp_expr = default_function_array_conversion (eloc, cmp_expr);
        }
      else
        cmp_expr = c_parser_binary_expression (parser, NULL, void_list_node);
      parens.skip_until_found_close (parser);
      if (cmp_expr.value == error_mark_node)
        goto saw_error;
      if (r)
        {
          if (!c_tree_equal (cmp_expr.value, unfolded_lhs))
            goto bad_if;
          cmp_expr.value = rhs1;
          rhs1 = NULL_TREE;
          gcc_assert (TREE_CODE (cmp_expr.value) == EQ_EXPR);
        }
      if (TREE_CODE (cmp_expr.value) == EQ_EXPR)
        ;
      else if (!structured_block && code == OMP_ATOMIC_CAPTURE_NEW)
        {
          error_at (EXPR_LOC_OR_LOC (cmp_expr.value, eloc),
                    "expected %<==%> comparison in %<if%> condition");
          goto saw_error;
        }
      else if (TREE_CODE (cmp_expr.value) != GT_EXPR
               && TREE_CODE (cmp_expr.value) != LT_EXPR)
        {
          error_at (EXPR_LOC_OR_LOC (cmp_expr.value, eloc),
                    "expected %<==%>, %<<%> or %<>%> comparison in %<if%> "
                    "condition");
          goto saw_error;
        }
      if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
        goto saw_error;

      extra_scope = true;
      eloc = c_parser_peek_token (parser)->location;
      expr = c_parser_cast_expression (parser, NULL);
      lhs = expr.value;
      expr = default_function_array_conversion (eloc, expr);
      unfolded_lhs = expr.value;
      lhs = c_fully_fold (lhs, false, NULL, true);
      orig_lhs = lhs;
      if (lhs == error_mark_node)
        goto saw_error;
      if (!lvalue_p (unfolded_lhs))
        lhs = non_lvalue (lhs);
      if (!c_parser_next_token_is (parser, CPP_EQ))
        {
          c_parser_error (parser, "expected %<=%>");
          goto saw_error;
        }
      c_parser_consume_token (parser);
      eloc = c_parser_peek_token (parser)->location;
      expr = c_parser_expr_no_commas (parser, NULL);
      rhs1 = expr.value;

      if (!c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
        goto saw_error;

      if (!c_parser_require (parser, CPP_CLOSE_BRACE, "expected %<}%>"))
        goto saw_error;

      extra_scope = false;
      no_semicolon = true;

      if (c_tree_equal (TREE_OPERAND (cmp_expr.value, 0), unfolded_lhs))
        {
          if (TREE_CODE (cmp_expr.value) == EQ_EXPR)
            {
              opcode = COND_EXPR;
              rhs = c_fully_fold (TREE_OPERAND (cmp_expr.value, 1),
                                  false, NULL, true);
              rhs1 = c_fully_fold (rhs1, false, NULL, true);
            }
          else if (c_tree_equal (TREE_OPERAND (cmp_expr.value, 1), rhs1))
            {
              opcode = (TREE_CODE (cmp_expr.value) == GT_EXPR
                        ? MIN_EXPR : MAX_EXPR);
              rhs = c_fully_fold (rhs1, false, NULL, true);
              rhs1 = c_fully_fold (TREE_OPERAND (cmp_expr.value, 0),
                                   false, NULL, true);
            }
          else
            goto bad_if;
        }
      else if (TREE_CODE (cmp_expr.value) == EQ_EXPR)
        goto bad_if;
      else if (c_tree_equal (TREE_OPERAND (cmp_expr.value, 1), unfolded_lhs)
               && c_tree_equal (TREE_OPERAND (cmp_expr.value, 0), rhs1))
        {
          opcode = (TREE_CODE (cmp_expr.value) == GT_EXPR
                    ? MAX_EXPR : MIN_EXPR);
          rhs = c_fully_fold (rhs1, false, NULL, true);
          rhs1 = c_fully_fold (TREE_OPERAND (cmp_expr.value, 1),
                               false, NULL, true);
        }
      else
        {
        bad_if:
          c_parser_error (parser,
                          "invalid form of %<#pragma omp atomic compare%>");
          goto saw_error;
        }

      if (c_parser_next_token_is_keyword (parser, RID_ELSE))
        {
          if (code != OMP_ATOMIC_CAPTURE_NEW
              || (structured_block && r == NULL_TREE)
              || TREE_CODE (cmp_expr.value) != EQ_EXPR)
            {
              eloc = c_parser_peek_token (parser)->location;
              error_at (eloc, "unexpected %<else%>");
              goto saw_error;
            }

          c_parser_consume_token (parser);

          if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
            goto saw_error;

          extra_scope = true;
          v = c_parser_cast_expression (parser, NULL).value;
          non_lvalue_p = !lvalue_p (v);
          v = c_fully_fold (v, false, NULL, true);
          if (v == error_mark_node)
            goto saw_error;
          if (non_lvalue_p)
            v = non_lvalue (v);
          if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
            goto saw_error;

          expr = c_parser_expr_no_commas (parser, NULL);

          if (!c_tree_equal (expr.value, unfolded_lhs))
            goto bad_if;

          if (!c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
            goto saw_error;

          if (!c_parser_require (parser, CPP_CLOSE_BRACE, "expected %<}%>"))
            goto saw_error;

          extra_scope = false;
          code = OMP_ATOMIC_CAPTURE_OLD;
          if (r == NULL_TREE)
            /* Signal to c_finish_omp_atomic that in
               if (x == e) { x = d; } else { v = x; }
               case the store to v should be conditional.  */
            r = void_list_node;
        }
      else if (code == OMP_ATOMIC_CAPTURE_NEW && !structured_block)
        {
          c_parser_require_keyword (parser, RID_ELSE, "expected %<else%>");
          goto saw_error;
        }
      else if (code == OMP_ATOMIC_CAPTURE_NEW
               && r != NULL_TREE
               && v == NULL_TREE)
        code = OMP_ATOMIC;
      goto stmt_done;
    }
  eloc = c_parser_peek_token (parser)->location;
  expr = c_parser_cast_expression (parser, NULL);
  lhs = expr.value;
  expr = default_function_array_conversion (eloc, expr);
  unfolded_lhs = expr.value;
  lhs = c_fully_fold (lhs, false, NULL, true);
  orig_lhs = lhs;
  switch (TREE_CODE (lhs))
    {
    invalid_compare:
      error_at (eloc, "invalid form of %<pragma omp atomic compare%>");
      /* FALLTHRU */
    case ERROR_MARK:
    saw_error:
      c_parser_skip_to_end_of_block_or_statement (parser);
      if (extra_scope && c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
        c_parser_consume_token (parser);
      if (structured_block)
        {
          if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
            c_parser_consume_token (parser);
          else if (code == OMP_ATOMIC_CAPTURE_NEW)
            {
              c_parser_skip_to_end_of_block_or_statement (parser);
              if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
                c_parser_consume_token (parser);
            }
        }
      return;

    case POSTINCREMENT_EXPR:
      if (code == OMP_ATOMIC_CAPTURE_NEW && !structured_block)
        code = OMP_ATOMIC_CAPTURE_OLD;
      /* FALLTHROUGH */
    case PREINCREMENT_EXPR:
      lhs = TREE_OPERAND (lhs, 0);
      unfolded_lhs = NULL_TREE;
      opcode = PLUS_EXPR;
      rhs = integer_one_node;
      if (compare)
        goto invalid_compare;
      break;

    case POSTDECREMENT_EXPR:
      if (code == OMP_ATOMIC_CAPTURE_NEW && !structured_block)
        code = OMP_ATOMIC_CAPTURE_OLD;
      /* FALLTHROUGH */
    case PREDECREMENT_EXPR:
      lhs = TREE_OPERAND (lhs, 0);
      unfolded_lhs = NULL_TREE;
      opcode = MINUS_EXPR;
      rhs = integer_one_node;
      if (compare)
        goto invalid_compare;
      break;

    case COMPOUND_EXPR:
      if (TREE_CODE (TREE_OPERAND (lhs, 0)) == SAVE_EXPR
          && TREE_CODE (TREE_OPERAND (lhs, 1)) == COMPOUND_EXPR
          && TREE_CODE (TREE_OPERAND (TREE_OPERAND (lhs, 1), 0)) == MODIFY_EXPR
          && TREE_OPERAND (TREE_OPERAND (lhs, 1), 1) == TREE_OPERAND (lhs, 0)
          && C_BOOLEAN_TYPE_P (TREE_TYPE (TREE_OPERAND (TREE_OPERAND
                                              (TREE_OPERAND (lhs, 1), 0), 0))))
        /* Undo effects of boolean_increment for post {in,de}crement.  */
        lhs = TREE_OPERAND (TREE_OPERAND (lhs, 1), 0);
      /* FALLTHRU */
    case MODIFY_EXPR:
      if (TREE_CODE (lhs) == MODIFY_EXPR
          && C_BOOLEAN_TYPE_P (TREE_TYPE (TREE_OPERAND (lhs, 0))))
        {
          /* Undo effects of boolean_increment.  */
          if (integer_onep (TREE_OPERAND (lhs, 1)))
            {
              /* This is pre or post increment.  */
              rhs = TREE_OPERAND (lhs, 1);
              lhs = TREE_OPERAND (lhs, 0);
              unfolded_lhs = NULL_TREE;
              opcode = NOP_EXPR;
              if (code == OMP_ATOMIC_CAPTURE_NEW
                  && !structured_block
                  && TREE_CODE (orig_lhs) == COMPOUND_EXPR)
                code = OMP_ATOMIC_CAPTURE_OLD;
              if (compare)
                goto invalid_compare;
              break;
            }
          if (TREE_CODE (TREE_OPERAND (lhs, 1)) == TRUTH_NOT_EXPR
              && TREE_OPERAND (lhs, 0)
                 == TREE_OPERAND (TREE_OPERAND (lhs, 1), 0))
            {
              /* This is pre or post decrement.  */
              rhs = TREE_OPERAND (lhs, 1);
              lhs = TREE_OPERAND (lhs, 0);
              unfolded_lhs = NULL_TREE;
              opcode = NOP_EXPR;
              if (code == OMP_ATOMIC_CAPTURE_NEW
                  && !structured_block
                  && TREE_CODE (orig_lhs) == COMPOUND_EXPR)
                code = OMP_ATOMIC_CAPTURE_OLD;
              if (compare)
                goto invalid_compare;
              break;
            }
        }
      /* FALLTHRU */
    default:
      if (!lvalue_p (unfolded_lhs))
        lhs = non_lvalue (lhs);
      if (compare && !c_parser_next_token_is (parser, CPP_EQ))
        {
          c_parser_error (parser, "expected %<=%>");
          goto saw_error;
        }
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_MULT_EQ:
          opcode = MULT_EXPR;
          break;
        case CPP_DIV_EQ:
          opcode = TRUNC_DIV_EXPR;
          break;
        case CPP_PLUS_EQ:
          opcode = PLUS_EXPR;
          break;
        case CPP_MINUS_EQ:
          opcode = MINUS_EXPR;
          break;
        case CPP_LSHIFT_EQ:
          opcode = LSHIFT_EXPR;
          break;
        case CPP_RSHIFT_EQ:
          opcode = RSHIFT_EXPR;
          break;
        case CPP_AND_EQ:
          opcode = BIT_AND_EXPR;
          break;
        case CPP_OR_EQ:
          opcode = BIT_IOR_EXPR;
          break;
        case CPP_XOR_EQ:
          opcode = BIT_XOR_EXPR;
          break;
        case CPP_EQ:
          c_parser_consume_token (parser);
          eloc = c_parser_peek_token (parser)->location;
          expr = c_parser_expr_no_commas (parser, NULL, unfolded_lhs);
          rhs1 = expr.value;
          switch (TREE_CODE (rhs1))
            {
            case MULT_EXPR:
            case TRUNC_DIV_EXPR:
            case RDIV_EXPR:
            case PLUS_EXPR:
            case MINUS_EXPR:
            case LSHIFT_EXPR:
            case RSHIFT_EXPR:
            case BIT_AND_EXPR:
            case BIT_IOR_EXPR:
            case BIT_XOR_EXPR:
              if (compare)
                break;
              if (c_tree_equal (TREE_OPERAND (rhs1, 0), unfolded_lhs))
                {
                  opcode = TREE_CODE (rhs1);
                  rhs = c_fully_fold (TREE_OPERAND (rhs1, 1), false, NULL,
                                      true);
                  rhs1 = c_fully_fold (TREE_OPERAND (rhs1, 0), false, NULL,
                                       true);
                  goto stmt_done;
                }
              if (c_tree_equal (TREE_OPERAND (rhs1, 1), unfolded_lhs))
                {
                  opcode = TREE_CODE (rhs1);
                  rhs = c_fully_fold (TREE_OPERAND (rhs1, 0), false, NULL,
                                      true);
                  rhs1 = c_fully_fold (TREE_OPERAND (rhs1, 1), false, NULL,
                                       true);
                  swapped = !commutative_tree_code (opcode);
                  goto stmt_done;
                }
              break;
            case COND_EXPR:
              if (!compare)
                break;
              if (TREE_CODE (TREE_OPERAND (rhs1, 0)) != GT_EXPR
                  && TREE_CODE (TREE_OPERAND (rhs1, 0)) != LT_EXPR
                  && TREE_CODE (TREE_OPERAND (rhs1, 0)) != EQ_EXPR)
                break;
              if (!TREE_OPERAND (rhs1, 1))
                break;
              if (!c_tree_equal (TREE_OPERAND (rhs1, 2), unfolded_lhs))
                break;
              if (c_tree_equal (TREE_OPERAND (TREE_OPERAND (rhs1, 0), 0),
                                unfolded_lhs))
                {
                  if (TREE_CODE (TREE_OPERAND (rhs1, 0)) == EQ_EXPR)
                    {
                      opcode = COND_EXPR;
                      rhs = c_fully_fold (TREE_OPERAND (TREE_OPERAND (rhs1,
                                                                      0), 1),
                                          false, NULL, true);
                      rhs1 = c_fully_fold (TREE_OPERAND (rhs1, 1), false,
                                           NULL, true);
                      goto stmt_done;
                    }
                  if (c_tree_equal (TREE_OPERAND (TREE_OPERAND (rhs1, 0), 1),
                                    TREE_OPERAND (rhs1, 1)))
                    {
                      opcode = (TREE_CODE (TREE_OPERAND (rhs1, 0)) == GT_EXPR
                                ? MIN_EXPR : MAX_EXPR);
                      rhs = c_fully_fold (TREE_OPERAND (rhs1, 1), false, NULL,
                                          true);
                      rhs1 = c_fully_fold (TREE_OPERAND (TREE_OPERAND (rhs1,
                                                                       0), 0),
                                           false, NULL, true);
                      goto stmt_done;
                    }
                }
              else if (TREE_CODE (TREE_OPERAND (rhs1, 0)) == EQ_EXPR)
                break;
              else if (c_tree_equal (TREE_OPERAND (TREE_OPERAND (rhs1, 0), 1),
                                     unfolded_lhs))
                {
                  if (c_tree_equal (TREE_OPERAND (TREE_OPERAND (rhs1, 0), 0),
                                    TREE_OPERAND (rhs1, 1)))
                    {
                      opcode = (TREE_CODE (TREE_OPERAND (rhs1, 0)) == GT_EXPR
                                ? MAX_EXPR : MIN_EXPR);
                      rhs = c_fully_fold (TREE_OPERAND (rhs1, 1), false, NULL,
                                          true);
                      rhs1 = c_fully_fold (TREE_OPERAND (TREE_OPERAND (rhs1,
                                                                       0), 1),
                                           false, NULL, true);
                      goto stmt_done;
                    }
                }
              break;
            case EQ_EXPR:
              if (!compare
                  || code != OMP_ATOMIC_CAPTURE_NEW
                  || !structured_block
                  || v
                  || r)
                break;
              if (c_parser_next_token_is (parser, CPP_SEMICOLON)
                  && c_parser_peek_2nd_token (parser)->keyword == RID_IF)
                {
                  r = lhs;
                  lhs = NULL_TREE;
                  c_parser_consume_token (parser);
                  goto restart;
                }
              break;
            case ERROR_MARK:
              goto saw_error;
            default:
              break;
            }
          if (c_parser_peek_token (parser)->type == CPP_SEMICOLON)
            {
              if (structured_block && code == OMP_ATOMIC_CAPTURE_NEW)
                {
                  code = OMP_ATOMIC_CAPTURE_OLD;
                  v = lhs;
                  lhs = NULL_TREE;
                  expr = default_function_array_read_conversion (eloc, expr);
                  unfolded_lhs1 = expr.value;
                  lhs1 = c_fully_fold (unfolded_lhs1, false, NULL, true);
                  rhs1 = NULL_TREE;
                  c_parser_consume_token (parser);
                  goto restart;
                }
              if (structured_block && !compare)
                {
                  opcode = NOP_EXPR;
                  expr = default_function_array_read_conversion (eloc, expr);
                  rhs = c_fully_fold (expr.value, false, NULL, true);
                  rhs1 = NULL_TREE;
                  goto stmt_done;
                }
            }
          c_parser_error (parser, "invalid form of %<#pragma omp atomic%>");
          goto saw_error;
        default:
          c_parser_error (parser,
                          "invalid operator for %<#pragma omp atomic%>");
          goto saw_error;
        }

      /* Arrange to pass the location of the assignment operator to
         c_finish_omp_atomic.  */
      loc = c_parser_peek_token (parser)->location;
      c_parser_consume_token (parser);
      eloc = c_parser_peek_token (parser)->location;
      expr = c_parser_expression (parser);
      expr = default_function_array_read_conversion (eloc, expr);
      rhs = expr.value;
      rhs = c_fully_fold (rhs, false, NULL, true);
      break;
    }
stmt_done:
  if (structured_block && code == OMP_ATOMIC_CAPTURE_NEW && r == NULL_TREE)
    {
      if (!no_semicolon
          && !c_parser_require (parser, CPP_SEMICOLON, "expected %<;%>"))
        goto saw_error;
      no_semicolon = false;
      v = c_parser_cast_expression (parser, NULL).value;
      non_lvalue_p = !lvalue_p (v);
      v = c_fully_fold (v, false, NULL, true);
      if (v == error_mark_node)
        goto saw_error;
      if (non_lvalue_p)
        v = non_lvalue (v);
      if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
        goto saw_error;
      eloc = c_parser_peek_token (parser)->location;
      expr = c_parser_cast_expression (parser, NULL);
      lhs1 = expr.value;
      expr = default_function_array_read_conversion (eloc, expr);
      unfolded_lhs1 = expr.value;
      lhs1 = c_fully_fold (lhs1, false, NULL, true);
      if (lhs1 == error_mark_node)
        goto saw_error;
      if (!lvalue_p (unfolded_lhs1))
        lhs1 = non_lvalue (lhs1);
    }
  if (structured_block)
    {
      if (!no_semicolon)
        c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
      c_parser_require (parser, CPP_CLOSE_BRACE, "expected %<}%>");
    }
done:
  if (weak && opcode != COND_EXPR)
    {
      error_at (loc, "%<weak%> clause requires atomic equality comparison");
      weak = false;
    }
  if (unfolded_lhs && unfolded_lhs1
      && !c_tree_equal (unfolded_lhs, unfolded_lhs1))
    {
      error ("%<#pragma omp atomic capture%> uses two different "
             "expressions for memory");
      stmt = error_mark_node;
    }
  else
    stmt = c_finish_omp_atomic (loc, code, opcode, lhs, rhs, v, lhs1, rhs1, r,
                                swapped, memory_order, weak);
  if (stmt != error_mark_node)
    add_stmt (stmt);

  if (!structured_block && !no_semicolon)
    c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
}


/* OpenMP 2.5:
   # pragma omp barrier new-line
*/

static void
c_parser_omp_barrier (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);
  c_parser_skip_to_pragma_eol (parser);

  c_finish_omp_barrier (loc);
}

/* OpenMP 2.5:
   # pragma omp critical [(name)] new-line
     structured-block

   OpenMP 4.5:
   # pragma omp critical [(name) [hint(expression)]] new-line

  LOC is the location of the #pragma itself.  */

#define OMP_CRITICAL_CLAUSE_MASK                \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_HINT) )

static tree
c_parser_omp_critical (location_t loc, c_parser *parser, bool *if_p)
{
  tree stmt, name = NULL_TREE, clauses = NULL_TREE;

  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          name = c_parser_peek_token (parser)->value;
          c_parser_consume_token (parser);
          c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>");
        }
      else
        c_parser_error (parser, "expected identifier");

      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);
    }
  clauses = c_parser_omp_all_clauses (parser, OMP_CRITICAL_CLAUSE_MASK,
                                      "#pragma omp critical");
  stmt = c_parser_omp_structured_block (parser, if_p);
  return c_finish_omp_critical (loc, stmt, name, clauses);
}

/* OpenMP 5.0:
   # pragma omp depobj ( depobj ) depobj-clause new-line

   depobj-clause:
     depend (dependence-type : locator)
     destroy
     update (dependence-type)

   OpenMP 5.2 additionally:
     destroy ( depobj )

   dependence-type:
     in
     out
     inout
     mutexinout  */

static void
c_parser_omp_depobj (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);
  matching_parens parens;
  if (!parens.require_open (parser))
    {
      c_parser_skip_to_pragma_eol (parser);
      return;
    }

  tree depobj = c_parser_expr_no_commas (parser, NULL).value;
  if (depobj != error_mark_node)
    {
      if (!lvalue_p (depobj))
        {
          error_at (EXPR_LOC_OR_LOC (depobj, loc),
                    "%<depobj%> expression is not lvalue expression");
          depobj = error_mark_node;
        }
      else
        {
          tree addr = build_unary_op (EXPR_LOC_OR_LOC (depobj, loc), ADDR_EXPR,
                                      depobj, false);
          if (addr == error_mark_node)
            depobj = error_mark_node;
          else
            depobj = build_indirect_ref (EXPR_LOC_OR_LOC (depobj, loc),
                                         addr, RO_UNARY_STAR);
        }
    }

  parens.skip_until_found_close (parser);
  tree clause = NULL_TREE;
  enum omp_clause_depend_kind kind = OMP_CLAUSE_DEPEND_INVALID;
  if (c_parser_next_token_is (parser, CPP_COMMA))
    c_parser_consume_token (parser);
  location_t c_loc = c_parser_peek_token (parser)->location;
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      c_parser_consume_token (parser);
      if (!strcmp ("depend", p))
        {
          clause = c_parser_omp_clause_depend (parser, NULL_TREE);
          clause = c_finish_omp_clauses (clause, C_ORT_OMP);
          if (!clause)
            clause = error_mark_node;
        }
      else if (!strcmp ("destroy", p))
        {
          matching_parens c_parens;
          kind = OMP_CLAUSE_DEPEND_LAST;
          if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)
              && c_parens.require_open (parser))
            {
              tree destobj = c_parser_expr_no_commas (parser, NULL).value;
              if (!lvalue_p (destobj))
                error_at (EXPR_LOC_OR_LOC (destobj, c_loc),
                          "%<destroy%> expression is not lvalue expression");
              else if (depobj != error_mark_node
                       && !operand_equal_p (destobj, depobj,
                                            OEP_MATCH_SIDE_EFFECTS
                                            | OEP_LEXICOGRAPHIC))
                warning_at (EXPR_LOC_OR_LOC (destobj, c_loc), OPT_Wopenmp,
                            "the %<destroy%> expression %qE should be the same "
                            "as the %<depobj%> argument %qE", destobj, depobj);
              c_parens.skip_until_found_close (parser);
            }
        }
      else if (!strcmp ("update", p))
        {
          matching_parens c_parens;
          if (c_parens.require_open (parser))
            {
              location_t c2_loc = c_parser_peek_token (parser)->location;
              if (c_parser_next_token_is (parser, CPP_NAME))
                {
                  const char *p2
                    = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

                  c_parser_consume_token (parser);
                  if (!strcmp ("in", p2))
                    kind = OMP_CLAUSE_DEPEND_IN;
                  else if (!strcmp ("out", p2))
                    kind = OMP_CLAUSE_DEPEND_OUT;
                  else if (!strcmp ("inout", p2))
                    kind = OMP_CLAUSE_DEPEND_INOUT;
                  else if (!strcmp ("mutexinoutset", p2))
                    kind = OMP_CLAUSE_DEPEND_MUTEXINOUTSET;
                  else if (!strcmp ("inoutset", p2))
                    kind = OMP_CLAUSE_DEPEND_INOUTSET;
                }
              if (kind == OMP_CLAUSE_DEPEND_INVALID)
                {
                  clause = error_mark_node;
                  error_at (c2_loc, "expected %<in%>, %<out%>, %<inout%>, "
                                    "%<mutexinoutset%> or %<inoutset%>");
                }
              c_parens.skip_until_found_close (parser);
            }
          else
            clause = error_mark_node;
        }
    }
  if (!clause && kind == OMP_CLAUSE_DEPEND_INVALID)
    {
      clause = error_mark_node;
      error_at (c_loc, "expected %<depend%>, %<destroy%> or %<update%> clause");
    }
  c_parser_skip_to_pragma_eol (parser);

  c_finish_omp_depobj (loc, depobj, kind, clause);
}


/* OpenMP 2.5:
   # pragma omp flush flush-vars[opt] new-line

   flush-vars:
     ( variable-list )

   OpenMP 5.0:
   # pragma omp flush memory-order-clause new-line  */

static void
c_parser_omp_flush (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);
  enum memmodel mo = MEMMODEL_LAST;
  if (c_parser_next_token_is (parser, CPP_COMMA)
      && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
    c_parser_consume_token (parser);
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p
        = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      if (!strcmp (p, "seq_cst"))
        mo = MEMMODEL_SEQ_CST;
      else if (!strcmp (p, "acq_rel"))
        mo = MEMMODEL_ACQ_REL;
      else if (!strcmp (p, "release"))
        mo = MEMMODEL_RELEASE;
      else if (!strcmp (p, "acquire"))
        mo = MEMMODEL_ACQUIRE;
      else
        error_at (c_parser_peek_token (parser)->location,
                  "expected %<seq_cst%>, %<acq_rel%>, %<release%> or "
                  "%<acquire%>");
      c_parser_consume_token (parser);
    }
  if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      if (mo != MEMMODEL_LAST)
        error_at (c_parser_peek_token (parser)->location,
                  "%<flush%> list specified together with memory order "
                  "clause");
      c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ERROR, NULL);
    }
  else if (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    c_parser_error (parser, "expected %<(%> or end of line");
  c_parser_skip_to_pragma_eol (parser);

  c_finish_omp_flush (loc, mo);
}

/* Return true if next tokens contain a standard attribute that contains
   omp::directive (DIRECTIVE).  */

static bool
c_parser_omp_section_scan (c_parser *parser, const char *directive,
                           bool tentative)
{
  if (!c_parser_nth_token_starts_std_attributes (parser, 1))
    return false;
  unsigned int n = 3;
  if (!c_parser_check_balanced_raw_token_sequence (parser, &n))
    return false;
  c_token *token = c_parser_peek_nth_token_raw (parser, n);
  if (token->type != CPP_CLOSE_SQUARE)
    return false;
  token = c_parser_peek_nth_token_raw (parser, n + 1);
  if (token->type != CPP_CLOSE_SQUARE)
    return false;
  if (n < 9)
    return false;
  if (c_parser_peek_nth_token_raw (parser, 3)->type == CPP_NAME
      && c_parser_peek_nth_token_raw (parser, 4)->type == CPP_OPEN_PAREN
      && c_parser_peek_nth_token_raw (parser, 5)->type == CPP_NAME)
    {
      tree first = c_parser_peek_nth_token_raw (parser, 3)->value;
      tree second = c_parser_peek_nth_token_raw (parser, 5)->value;
      if (strcmp (IDENTIFIER_POINTER (first), "directive")
          && strcmp (IDENTIFIER_POINTER (first), "__directive__"))
        return false;
      if (strcmp (IDENTIFIER_POINTER (second), directive))
        return false;
    }
  if (tentative)
    return true;
  location_t first_loc = c_parser_peek_token (parser)->location;
  location_t last_loc = c_parser_peek_nth_token_raw (parser, n + 1)->location;
  location_t middle_loc = UNKNOWN_LOCATION;
  tree std_attrs = c_parser_std_attribute_specifier_sequence (parser);
  bool seen = false;
  int cnt = 0;
  for (tree attr = std_attrs; attr; attr = TREE_CHAIN (attr))
    if (is_attribute_namespace_p ("omp", attr)
        && is_attribute_p ("directive", get_attribute_name (attr)))
      {
        for (tree a = TREE_VALUE (attr); a; a = TREE_CHAIN (a))
          {
            tree d = TREE_VALUE (a);
            gcc_assert (TREE_CODE (d) == C_TOKEN_VEC);
            c_token *first = C_TOKEN_VEC_TOKENS (d)->address ();
            cnt++;
            if (first->type == CPP_NAME
                && strcmp (IDENTIFIER_POINTER (first->value),
                           directive) == 0)
              {
                seen = true;
                if (middle_loc == UNKNOWN_LOCATION)
                  middle_loc = first->location;
              }
          }
      }
  if (!seen)
    return false;
  if (cnt != 1 || TREE_CHAIN (std_attrs))
    {
      error_at (make_location (first_loc, last_loc, middle_loc),
                "%<[[omp::directive(%s)]]%> must be the only specified "
                "attribute on a statement", directive);
      return false;
    }
  c_parser_handle_statement_omp_attributes (parser, std_attrs, NULL);
  return true;
}

/* Parse an OpenMP structured block sequence.  KIND is the corresponding
   separating directive.  */

static tree
c_parser_omp_structured_block_sequence (c_parser *parser,
                                        enum pragma_kind kind)
{
  tree stmt = push_stmt_list ();
  c_parser_statement (parser, NULL);
  do
    {
      if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
        break;
      if (c_parser_next_token_is (parser, CPP_EOF))
        break;

      if (kind != PRAGMA_NONE
          && c_parser_peek_token (parser)->pragma_kind == kind)
        break;

      if (kind != PRAGMA_NONE
          && c_parser_omp_section_scan (parser,
                                        kind == PRAGMA_OMP_SCAN
                                        ? "scan" : "section", false))
        break;

      c_parser_statement (parser, NULL);
    }
  while (1);
  return pop_stmt_list (stmt);
}

/* OpenMP 5.0:

   scan-loop-body:
     { structured-block scan-directive structured-block }  */

static void
c_parser_omp_scan_loop_body (c_parser *parser, bool open_brace_parsed)
{
  tree substmt;
  location_t loc;
  tree clauses = NULL_TREE;
  bool found_scan = false;

  loc = c_parser_peek_token (parser)->location;
  if (!open_brace_parsed
      && !c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
    {
      /* Avoid skipping until the end of the block.  */
      parser->error = false;
      return;
    }

  if (c_parser_peek_token (parser)->pragma_kind != PRAGMA_OMP_SCAN)
    substmt = c_parser_omp_structured_block_sequence (parser, PRAGMA_OMP_SCAN);
  else
    {
      warning_at (c_parser_peek_token (parser)->location, OPT_Wopenmp,
                  "%<#pragma omp scan%> with zero preceding executable "
                  "statements");
      substmt = build_empty_stmt (loc);
    }
  substmt = build2 (OMP_SCAN, void_type_node, substmt, NULL_TREE);
  SET_EXPR_LOCATION (substmt, loc);
  add_stmt (substmt);

  loc = c_parser_peek_token (parser)->location;
  if (c_parser_peek_token (parser)->pragma_kind == PRAGMA_OMP_SCAN)
    {
      enum omp_clause_code clause = OMP_CLAUSE_ERROR;
      found_scan = true;

      c_parser_consume_pragma (parser);

      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);

      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          const char *p
            = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
          if (strcmp (p, "inclusive") == 0)
            clause = OMP_CLAUSE_INCLUSIVE;
          else if (strcmp (p, "exclusive") == 0)
            clause = OMP_CLAUSE_EXCLUSIVE;
        }
      if (clause != OMP_CLAUSE_ERROR)
        {
          c_parser_consume_token (parser);
          clauses = c_parser_omp_var_list_parens (parser, clause, NULL_TREE);
        }
      else
        c_parser_error (parser, "expected %<inclusive%> or "
                                "%<exclusive%> clause");
      c_parser_skip_to_pragma_eol (parser);
    }
  else
    error ("expected %<#pragma omp scan%>");

  clauses = c_finish_omp_clauses (clauses, C_ORT_OMP);
  if (!c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
    substmt = c_parser_omp_structured_block_sequence (parser, PRAGMA_NONE);
  else
    {
      if (found_scan)
        warning_at (loc, OPT_Wopenmp,
                    "%<#pragma omp scan%> with zero succeeding executable "
                    "statements");
      substmt = build_empty_stmt (loc);
    }
  substmt = build2 (OMP_SCAN, void_type_node, substmt, clauses);
  SET_EXPR_LOCATION (substmt, loc);
  add_stmt (substmt);

  c_parser_skip_until_found (parser, CPP_CLOSE_BRACE,
                             "expected %<}%>");
}


/* This function parses a single level of a loop nest, invoking itself
   recursively if necessary.

   loop-nest :: for (...) loop-body
   loop-body :: loop-nest
             |  { [intervening-code] loop-body [intervening-code] }
             |  final-loop-body
   intervening-code :: structured-block-sequence
   final-loop-body :: structured-block

   For a collapsed loop nest, only a single OMP_FOR is built, pulling out
   all the iterator information from the inner loops into the
   parser->omp_for_parse_state structure.

   The iterator decl, init, cond, and incr are stored in vectors.

   Initialization code for iterator variables is collected into
   parser->omp_for_parse_state->pre_body and ends up inserted directly
   into the OMP_FOR structure.  */

static tree
c_parser_omp_loop_nest (c_parser *parser, bool *if_p)
{
  tree decl, cond, incr, init;
  tree body = NULL_TREE;
  matching_parens parens;
  bool moreloops;
  unsigned char save_in_statement;
  tree loop_scope;
  location_t loc;
  struct omp_for_parse_data *omp_for_parse_state
    = parser->omp_for_parse_state;
  gcc_assert (omp_for_parse_state);
  int depth = omp_for_parse_state->depth;

  /* We have already matched the FOR token but not consumed it yet.  */
  loc = c_parser_peek_token (parser)->location;
  gcc_assert (c_parser_next_token_is_keyword (parser, RID_FOR));
  c_parser_consume_token (parser);

  /* Forbid break/continue in the loop initializer, condition, and
     increment expressions.  */
  save_in_statement = in_statement;
  in_statement = IN_OMP_BLOCK;

  /* We are not in intervening code now.  */
  omp_for_parse_state->in_intervening_code = false;

  if (!parens.require_open (parser))
    {
      omp_for_parse_state->fail = true;
      return NULL_TREE;
    }

  /* An implicit scope block surrounds each level of FOR loop, for
     declarations of iteration variables at this loop depth.  */
  loop_scope = c_begin_compound_stmt (true);

  /* Parse the initialization declaration or expression.  */
  if (c_parser_next_tokens_start_declaration (parser))
    {
      /* This is a declaration, which must be added to the pre_body code.  */
      tree this_pre_body = push_stmt_list ();
      c_in_omp_for = true;
      c_parser_declaration_or_fndef (parser, true, true, true, true, true);
      c_in_omp_for = false;
      this_pre_body = pop_stmt_list (this_pre_body);
      append_to_statement_list_force (this_pre_body,
                                      &(omp_for_parse_state->pre_body));
      decl = check_for_loop_decls (omp_for_parse_state->for_loc, flag_isoc99);
      if (decl == NULL)
        goto error_init;
      if (DECL_INITIAL (decl) == error_mark_node)
        decl = error_mark_node;
      init = decl;
    }
  else if (c_parser_next_token_is (parser, CPP_NAME)
           && c_parser_peek_2nd_token (parser)->type == CPP_EQ)
    {
      struct c_expr decl_exp;
      struct c_expr init_exp;
      location_t init_loc;

      decl_exp = c_parser_postfix_expression (parser);
      decl = decl_exp.value;

      c_parser_require (parser, CPP_EQ, "expected %<=%>");

      init_loc = c_parser_peek_token (parser)->location;
      init_exp = c_parser_expr_no_commas (parser, NULL);
      init_exp = default_function_array_read_conversion (init_loc,
                                                         init_exp);
      c_in_omp_for = true;
      init = build_modify_expr (init_loc, decl, decl_exp.original_type,
                                NOP_EXPR, init_loc, init_exp.value,
                                init_exp.original_type);
      c_in_omp_for = false;
      init = c_process_expr_stmt (init_loc, init);

      c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");
    }
  else
    {
    error_init:
      c_parser_error (parser,
                      "expected iteration declaration or initialization");
      c_parser_skip_until_found (parser, CPP_CLOSE_PAREN,
                                 "expected %<)%>");
      omp_for_parse_state->fail = true;
      goto parse_next;
    }

  /* Parse the loop condition.  */
  cond = NULL_TREE;
  if (c_parser_next_token_is_not (parser, CPP_SEMICOLON))
    {
      location_t cond_loc = c_parser_peek_token (parser)->location;
      c_in_omp_for = true;
      struct c_expr cond_expr
        = c_parser_binary_expression (parser, NULL, NULL_TREE);
      c_in_omp_for = false;

      cond = cond_expr.value;
      cond = c_objc_common_truthvalue_conversion (cond_loc, cond);
      switch (cond_expr.original_code)
        {
        case GT_EXPR:
        case GE_EXPR:
        case LT_EXPR:
        case LE_EXPR:
          break;
        case NE_EXPR:
          if (omp_for_parse_state->code != OACC_LOOP)
            break;
          /* FALLTHRU.  */
        default:
          /* Can't be cond = error_mark_node, because we want to preserve
             the location until c_finish_omp_for.  */
          cond = build1 (NOP_EXPR, boolean_type_node, error_mark_node);
          break;
        }
      protected_set_expr_location (cond, cond_loc);
    }
  c_parser_skip_until_found (parser, CPP_SEMICOLON, "expected %<;%>");

  /* Parse the increment expression.  */
  incr = NULL_TREE;
  if (c_parser_next_token_is_not (parser, CPP_CLOSE_PAREN))
    {
      location_t incr_loc = c_parser_peek_token (parser)->location;

      incr = c_process_expr_stmt (incr_loc,
                                  c_parser_expression (parser).value);
    }
  parens.skip_until_found_close (parser);

  if (decl == NULL || decl == error_mark_node || init == error_mark_node)
    omp_for_parse_state->fail = true;
  else
    {
      TREE_VEC_ELT (omp_for_parse_state->declv, depth) = decl;
      TREE_VEC_ELT (omp_for_parse_state->initv, depth) = init;
      TREE_VEC_ELT (omp_for_parse_state->condv, depth) = cond;
      TREE_VEC_ELT (omp_for_parse_state->incrv, depth) = incr;
    }

parse_next:
  moreloops = depth < omp_for_parse_state->count - 1;
  omp_for_parse_state->want_nested_loop = moreloops;
  if (moreloops && c_parser_next_token_is_keyword (parser, RID_FOR))
    {
      omp_for_parse_state->depth++;
      body = c_parser_omp_loop_nest (parser, if_p);
      omp_for_parse_state->depth--;
    }
  else if (moreloops && c_parser_next_token_is (parser, CPP_OPEN_BRACE))
    {
      /* This is the open brace in the loop-body grammar production.  Rather
         than trying to special-case braces, just parse it as a compound
         statement and handle the nested loop-body case there.  Note that
         when we see a further open brace inside the compound statement
         loop-body, we don't know whether it is the start of intervening
         code that is a compound statement, or a level of braces
         surrounding a nested loop-body.  Use the WANT_NESTED_LOOP state
         bit to ensure we have only one nested loop at each level.  */
      omp_for_parse_state->in_intervening_code = true;
      body = c_parser_compound_statement (parser, NULL);
      omp_for_parse_state->in_intervening_code = false;
      if (omp_for_parse_state->want_nested_loop)
        {
          /* We have already parsed the whole loop body and not found a
             nested loop.  */
          error_at (omp_for_parse_state->for_loc,
                    "not enough nested loops");
          omp_for_parse_state->fail = true;
        }
      if_p = NULL;
    }
  else
    {
      /* This is the final-loop-body case in the grammar: we have
         something that is not a FOR and not an open brace.  */
      if (moreloops)
        {
          /* If we were expecting a nested loop, give an error and mark
             that parsing has failed, and try to recover by parsing the
             body as regular code without further collapsing.  */
          error_at (omp_for_parse_state->for_loc,
                    "not enough nested loops");
          omp_for_parse_state->fail = true;
        }
      in_statement = IN_OMP_FOR;
      parser->omp_for_parse_state = NULL;
      body = push_stmt_list ();
      if (omp_for_parse_state->inscan)
        c_parser_omp_scan_loop_body (parser, false);
      else
        add_stmt (c_parser_c99_block_statement (parser, if_p));
      body = pop_stmt_list (body);
      parser->omp_for_parse_state = omp_for_parse_state;
    }
  in_statement = save_in_statement;
  omp_for_parse_state->want_nested_loop = false;
  omp_for_parse_state->in_intervening_code = true;

  /* Pop and return the implicit scope surrounding this level of loop.
     If the iteration variable at this depth was bound in the for loop,
     pull out and save the binding.  Later in c_parser_omp_for_loop,
     these bindings will be moved to the scope surrounding the entire
     OMP_FOR.  That keeps the gimplifier happy later on, and meanwhile
     we have already resolved all references to the iteration variable
     in its true scope.  */
  add_stmt (body);
  body = c_end_compound_stmt (loc, loop_scope, true);
  if (decl && TREE_CODE (body) == BIND_EXPR)
    {
      tree t = BIND_EXPR_VARS (body);
      tree prev = NULL_TREE, next = NULL_TREE;
      while (t)
        {
          next = DECL_CHAIN (t);
          if (t == decl)
            {
              if (prev)
                DECL_CHAIN (prev) = next;
              else
                {
                  BIND_EXPR_VARS (body) = next;
                  BLOCK_VARS (BIND_EXPR_BLOCK (body)) = next;
                }
              DECL_CHAIN (t) = omp_for_parse_state->bindings;
              omp_for_parse_state->bindings = t;
              break;
            }
          else
            {
              prev = t;
              t = next;
            }
        }
      if (BIND_EXPR_VARS (body) == NULL_TREE)
        body = BIND_EXPR_BODY (body);
    }

  return body;
}

/* Parse the restricted form of loop statements allowed by OpenACC and OpenMP.
   The real trick here is to determine the loop control variable early
   so that we can push a new decl if necessary to make it private.
   LOC is the location of the "acc" or "omp" in "#pragma acc" or "#pragma omp",
   respectively.  */

static tree
c_parser_omp_for_loop (location_t loc, c_parser *parser, enum tree_code code,
                       tree clauses, tree *cclauses, bool *if_p)
{
  tree body, stmt, cl;
  tree ret = NULL_TREE;
  tree ordered_cl = NULL_TREE;
  int i, collapse = 1, ordered = 0, count;
  bool tiling = false;
  bool inscan = false;
  struct omp_for_parse_data data;
  struct omp_for_parse_data *save_data = parser->omp_for_parse_state;

  for (cl = clauses; cl; cl = OMP_CLAUSE_CHAIN (cl))
    if (OMP_CLAUSE_CODE (cl) == OMP_CLAUSE_COLLAPSE)
      collapse = tree_to_shwi (OMP_CLAUSE_COLLAPSE_EXPR (cl));
    else if (OMP_CLAUSE_CODE (cl) == OMP_CLAUSE_TILE)
      {
        tiling = true;
        collapse = list_length (OMP_CLAUSE_TILE_LIST (cl));
      }
    else if (OMP_CLAUSE_CODE (cl) == OMP_CLAUSE_ORDERED
             && OMP_CLAUSE_ORDERED_EXPR (cl))
      {
        ordered_cl = cl;
        ordered = tree_to_shwi (OMP_CLAUSE_ORDERED_EXPR (cl));
      }
    else if (OMP_CLAUSE_CODE (cl) == OMP_CLAUSE_REDUCTION
             && OMP_CLAUSE_REDUCTION_INSCAN (cl)
             && (code == OMP_SIMD || code == OMP_FOR))
      inscan = true;

  if (ordered && ordered < collapse)
    {
      error_at (OMP_CLAUSE_LOCATION (ordered_cl),
                "%<ordered%> clause parameter is less than %<collapse%>");
      OMP_CLAUSE_ORDERED_EXPR (ordered_cl)
        = build_int_cst (NULL_TREE, collapse);
      ordered = collapse;
    }

  gcc_assert (tiling || (collapse >= 1 && ordered >= 0));
  count = ordered ? ordered : collapse;

  if (!c_parser_next_token_is_keyword (parser, RID_FOR))
    {
      c_parser_error (parser, "for statement expected");
      return NULL;
    }

  /* Initialize parse state for recursive descent.  */
  data.declv = make_tree_vec (count);
  data.initv = make_tree_vec (count);
  data.condv = make_tree_vec (count);
  data.incrv = make_tree_vec (count);
  data.pre_body = NULL_TREE;;
  data.bindings = NULL_TREE;
  data.for_loc = c_parser_peek_token (parser)->location;
  data.count = count;
  data.depth = 0;
  data.want_nested_loop = true;
  data.ordered = ordered > 0;
  data.in_intervening_code = false;
  data.perfect_nesting_fail = false;
  data.fail = false;
  data.inscan = inscan;
  data.saw_intervening_code = false;
  data.code = code;
  parser->omp_for_parse_state = &data;

  body = c_parser_omp_loop_nest (parser, if_p);

  /* Add saved bindings for iteration variables that were declared in
     the nested for loop to the scope surrounding the entire loop.  */
  for (tree t = data.bindings; t; )
    {
      tree n = TREE_CHAIN (t);
      TREE_CHAIN (t) = NULL_TREE;
      pushdecl (t);
      t = n;
    }

  /* Only bother calling c_finish_omp_for if we haven't already generated
     an error from the initialization parsing.  */
  if (!data.fail)
    {
      c_in_omp_for = true;
      stmt = c_finish_omp_for (loc, code, data.declv, NULL, data.initv,
                               data.condv, data.incrv,
                               body, data.pre_body, true);
      c_in_omp_for = false;

      /* Check for iterators appearing in lb, b or incr expressions.  */
      if (stmt && !c_omp_check_loop_iv (stmt, data.declv, NULL))
        stmt = NULL_TREE;

      /* Check for errors involving lb/ub/incr expressions referencing
         variables declared in intervening code.  */
      if (data.saw_intervening_code
          && !c_omp_check_loop_binding_exprs (stmt, NULL))
        stmt = NULL_TREE;

      if (stmt)
        {
          add_stmt (stmt);

          for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (stmt)); i++)
            {
              tree init = TREE_VEC_ELT (OMP_FOR_INIT (stmt), i);
              gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
              tree decl = TREE_OPERAND (init, 0);
              tree cond = TREE_VEC_ELT (OMP_FOR_COND (stmt), i);
              gcc_assert (COMPARISON_CLASS_P (cond));
              gcc_assert (TREE_OPERAND (cond, 0) == decl);

              tree op0 = TREE_OPERAND (init, 1);
              if (!OMP_FOR_NON_RECTANGULAR (stmt)
                  || TREE_CODE (op0) != TREE_VEC)
                TREE_OPERAND (init, 1) = c_fully_fold (op0, false, NULL);
              else
                {
                  TREE_VEC_ELT (op0, 1)
                    = c_fully_fold (TREE_VEC_ELT (op0, 1), false, NULL);
                  TREE_VEC_ELT (op0, 2)
                    = c_fully_fold (TREE_VEC_ELT (op0, 2), false, NULL);
                }

              tree op1 = TREE_OPERAND (cond, 1);
              if (!OMP_FOR_NON_RECTANGULAR (stmt)
                  || TREE_CODE (op1) != TREE_VEC)
                TREE_OPERAND (cond, 1) = c_fully_fold (op1, false, NULL);
              else
                {
                  TREE_VEC_ELT (op1, 1)
                    = c_fully_fold (TREE_VEC_ELT (op1, 1), false, NULL);
                  TREE_VEC_ELT (op1, 2)
                    = c_fully_fold (TREE_VEC_ELT (op1, 2), false, NULL);
                }
            }

          if (cclauses != NULL
              && cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL] != NULL)
            {
              tree *c;
              for (c = &cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL]; *c ; )
                if (OMP_CLAUSE_CODE (*c) != OMP_CLAUSE_FIRSTPRIVATE
                    && OMP_CLAUSE_CODE (*c) != OMP_CLAUSE_LASTPRIVATE)
                  c = &OMP_CLAUSE_CHAIN (*c);
                else
                  {
                    for (i = 0; i < count; i++)
                      if (TREE_VEC_ELT (data.declv, i) == OMP_CLAUSE_DECL (*c))
                        break;
                    if (i == count)
                      c = &OMP_CLAUSE_CHAIN (*c);
                    else if (OMP_CLAUSE_CODE (*c) == OMP_CLAUSE_FIRSTPRIVATE)
                      {
                        error_at (loc,
                                  "iteration variable %qD should not be firstprivate",
                                  OMP_CLAUSE_DECL (*c));
                        *c = OMP_CLAUSE_CHAIN (*c);
                      }
                    else
                      {
                        /* Move lastprivate (decl) clause to
                           OMP_FOR_CLAUSES.  */
                        tree l = *c;
                        *c = OMP_CLAUSE_CHAIN (*c);
                        if (code == OMP_SIMD)
                          {
                            OMP_CLAUSE_CHAIN (l)
                              = cclauses[C_OMP_CLAUSE_SPLIT_FOR];
                            cclauses[C_OMP_CLAUSE_SPLIT_FOR] = l;
                          }
                        else
                          {
                            OMP_CLAUSE_CHAIN (l) = clauses;
                            clauses = l;
                          }
                      }
                  }
            }
          OMP_FOR_CLAUSES (stmt) = clauses;
        }
      ret = stmt;
    }

  parser->omp_for_parse_state = save_data;
  return ret;
}

/* Helper function for OpenMP parsing, split clauses and call
   finish_omp_clauses on each of the set of clauses afterwards.  */

static void
omp_split_clauses (location_t loc, enum tree_code code,
                   omp_clause_mask mask, tree clauses, tree *cclauses)
{
  int i;
  c_omp_split_clauses (loc, code, mask, clauses, cclauses);
  for (i = 0; i < C_OMP_CLAUSE_SPLIT_COUNT; i++)
    if (cclauses[i])
      cclauses[i] = c_finish_omp_clauses (cclauses[i],
                                          i == C_OMP_CLAUSE_SPLIT_TARGET
                                          ? C_ORT_OMP_TARGET : C_ORT_OMP);
}

/* OpenMP 5.0:
   #pragma omp loop loop-clause[optseq] new-line
     for-loop

   LOC is the location of the #pragma token.
*/

#define OMP_LOOP_CLAUSE_MASK                                    \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_BIND)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDER))

static tree
c_parser_omp_loop (location_t loc, c_parser *parser,
                   char *p_name, omp_clause_mask mask, tree *cclauses,
                   bool *if_p)
{
  tree block, clauses, ret;

  strcat (p_name, " loop");
  mask |= OMP_LOOP_CLAUSE_MASK;

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_LOOP, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_LOOP];
    }

  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_for_loop (loc, parser, OMP_LOOP, clauses, cclauses, if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

/* OpenMP 4.0:
   #pragma omp simd simd-clause[optseq] new-line
     for-loop

   LOC is the location of the #pragma token.
*/

#define OMP_SIMD_CLAUSE_MASK                                    \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SAFELEN)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SIMDLEN)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINEAR)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALIGNED)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NONTEMPORAL)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDER))

static tree
c_parser_omp_simd (location_t loc, c_parser *parser,
                   char *p_name, omp_clause_mask mask, tree *cclauses,
                   bool *if_p)
{
  tree block, clauses, ret;

  strcat (p_name, " simd");
  mask |= OMP_SIMD_CLAUSE_MASK;

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_SIMD, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_SIMD];
    }

  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_for_loop (loc, parser, OMP_SIMD, clauses, cclauses, if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

/* OpenMP 2.5:
   #pragma omp for for-clause[optseq] new-line
     for-loop

   OpenMP 4.0:
   #pragma omp for simd for-simd-clause[optseq] new-line
     for-loop

   LOC is the location of the #pragma token.
*/

#define OMP_FOR_CLAUSE_MASK                                     \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINEAR)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDERED)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SCHEDULE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDER))

static tree
c_parser_omp_for (location_t loc, c_parser *parser,
                  char *p_name, omp_clause_mask mask, tree *cclauses,
                  bool *if_p)
{
  tree block, clauses, ret;

  strcat (p_name, " for");
  mask |= OMP_FOR_CLAUSE_MASK;
  /* parallel for{, simd} disallows nowait clause, but for
     target {teams distribute ,}parallel for{, simd} it should be accepted.  */
  if (cclauses && (mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)) == 0)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT);
  /* Composite distribute parallel for{, simd} disallows ordered clause.  */
  if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DIST_SCHEDULE)) != 0)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDERED);

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      if (strcmp (p, "simd") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_simd (loc, parser, p_name, mask, cclauses,
                                      if_p);
          block = c_begin_compound_stmt (true);
          ret = c_parser_omp_simd (loc, parser, p_name, mask, cclauses, if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL_TREE)
            return ret;
          ret = make_node (OMP_FOR);
          TREE_TYPE (ret) = void_type_node;
          OMP_FOR_BODY (ret) = block;
          OMP_FOR_CLAUSES (ret) = cclauses[C_OMP_CLAUSE_SPLIT_FOR];
          SET_EXPR_LOCATION (ret, loc);
          add_stmt (ret);
          return ret;
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  /* Composite distribute parallel for disallows linear clause.  */
  if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DIST_SCHEDULE)) != 0)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINEAR);

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_FOR, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_FOR];
    }

  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_for_loop (loc, parser, OMP_FOR, clauses, cclauses, if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

static tree c_parser_omp_taskloop (location_t, c_parser *, char *,
                                   omp_clause_mask, tree *, bool *);

/* OpenMP 2.5:
   # pragma omp master new-line
     structured-block

   LOC is the location of the #pragma token.
*/

static tree
c_parser_omp_master (location_t loc, c_parser *parser,
                     char *p_name, omp_clause_mask mask, tree *cclauses,
                     bool *if_p)
{
  tree block, clauses, ret;

  strcat (p_name, " master");

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      if (strcmp (p, "taskloop") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_taskloop (loc, parser, p_name, mask, cclauses,
                                          if_p);
          block = c_begin_compound_stmt (true);
          ret = c_parser_omp_taskloop (loc, parser, p_name, mask, cclauses,
                                       if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL_TREE)
            return ret;
          ret = c_finish_omp_master (loc, block);
          OMP_MASTER_COMBINED (ret) = 1;
          return ret;
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  if (cclauses)
    {
      clauses = c_parser_omp_all_clauses (parser, mask, p_name, false);
      omp_split_clauses (loc, OMP_MASTER, mask, clauses, cclauses);
    }
  else
    c_parser_skip_to_pragma_eol (parser);

  return c_finish_omp_master (loc, c_parser_omp_structured_block (parser,
                                                                  if_p));
}

/* OpenMP 5.1:
   # pragma omp masked masked-clauses new-line
     structured-block

   LOC is the location of the #pragma token.
*/

#define OMP_MASKED_CLAUSE_MASK                                  \
        (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FILTER)

static tree
c_parser_omp_masked (location_t loc, c_parser *parser,
                     char *p_name, omp_clause_mask mask, tree *cclauses,
                     bool *if_p)
{
  tree block, clauses, ret;

  strcat (p_name, " masked");
  mask |= OMP_MASKED_CLAUSE_MASK;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      if (strcmp (p, "taskloop") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_taskloop (loc, parser, p_name, mask, cclauses,
                                          if_p);
          block = c_begin_compound_stmt (true);
          ret = c_parser_omp_taskloop (loc, parser, p_name, mask, cclauses,
                                       if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL_TREE)
            return ret;
          ret = c_finish_omp_masked (loc, block,
                                     cclauses[C_OMP_CLAUSE_SPLIT_MASKED]);
          OMP_MASKED_COMBINED (ret) = 1;
          return ret;
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_MASKED, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_MASKED];
    }

  return c_finish_omp_masked (loc, c_parser_omp_structured_block (parser,
                                                                  if_p),
                              clauses);
}

/* OpenMP 2.5:
   # pragma omp ordered new-line
     structured-block

   OpenMP 4.5:
   # pragma omp ordered ordered-clauses new-line
     structured-block

   # pragma omp ordered depend-clauses new-line

   OpenMP 5.2
   # pragma omp ordered doacross-clauses new-line  */

#define OMP_ORDERED_CLAUSE_MASK                                 \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_THREADS)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SIMD))

#define OMP_ORDERED_DEPEND_CLAUSE_MASK                          \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DOACROSS))

static bool
c_parser_omp_ordered (c_parser *parser, enum pragma_context context,
                      bool *if_p)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);

  if (context != pragma_stmt && context != pragma_compound)
    {
      c_parser_error (parser, "expected declaration specifiers");
      c_parser_skip_to_pragma_eol (parser, false);
      return false;
    }

  int n = 1;
  if (c_parser_next_token_is (parser, CPP_COMMA))
    n = 2;

  if (c_parser_peek_nth_token (parser, n)->type == CPP_NAME)
    {
      const char *p
        = IDENTIFIER_POINTER (c_parser_peek_nth_token (parser, n)->value);

      if (!strcmp ("depend", p) || !strcmp ("doacross", p))
        {
          if (!flag_openmp)     /* flag_openmp_simd  */
            {
              c_parser_skip_to_pragma_eol (parser, false);
              return false;
            }
          if (context == pragma_stmt)
            {
              error_at (loc,
                        "%<#pragma omp ordered%> with %qs clause may "
                        "only be used in compound statements", p);
              c_parser_skip_to_pragma_eol (parser, false);
              return true;
            }

          tree clauses
            = c_parser_omp_all_clauses (parser,
                                        OMP_ORDERED_DEPEND_CLAUSE_MASK,
                                        "#pragma omp ordered");
          c_finish_omp_ordered (loc, clauses, NULL_TREE);
          return false;
        }
    }

  tree clauses = c_parser_omp_all_clauses (parser, OMP_ORDERED_CLAUSE_MASK,
                                           "#pragma omp ordered");

  if (!flag_openmp      /* flag_openmp_simd  */
      && omp_find_clause (clauses, OMP_CLAUSE_SIMD) == NULL_TREE)
    return false;

  c_finish_omp_ordered (loc, clauses,
                        c_parser_omp_structured_block (parser, if_p));
  return true;
}

/* OpenMP 2.5:

   section-scope:
     { section-sequence }

   section-sequence:
     section-directive[opt] structured-block
     section-sequence section-directive structured-block

   OpenMP 5.1 allows structured-block-sequence instead of structured-block.

    SECTIONS_LOC is the location of the #pragma omp sections.  */

static tree
c_parser_omp_sections_scope (location_t sections_loc, c_parser *parser)
{
  tree stmt, substmt;
  bool error_suppress = false;
  location_t loc;

  loc = c_parser_peek_token (parser)->location;
  if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
    {
      /* Avoid skipping until the end of the block.  */
      parser->error = false;
      return NULL_TREE;
    }

  stmt = push_stmt_list ();

  if (c_parser_peek_token (parser)->pragma_kind != PRAGMA_OMP_SECTION
      && !c_parser_omp_section_scan (parser, "section", true))
    {
      substmt = c_parser_omp_structured_block_sequence (parser,
                                                        PRAGMA_OMP_SECTION);
      substmt = build1 (OMP_SECTION, void_type_node, substmt);
      SET_EXPR_LOCATION (substmt, loc);
      add_stmt (substmt);
    }

  while (1)
    {
      if (c_parser_next_token_is (parser, CPP_CLOSE_BRACE))
        break;
      if (c_parser_next_token_is (parser, CPP_EOF))
        break;

      loc = c_parser_peek_token (parser)->location;
      c_parser_omp_section_scan (parser, "section", false);
      if (c_parser_peek_token (parser)->pragma_kind == PRAGMA_OMP_SECTION)
        {
          c_parser_consume_pragma (parser);
          c_parser_skip_to_pragma_eol (parser);
          error_suppress = false;
        }
      else if (!error_suppress)
        {
          error_at (loc, "expected %<#pragma omp section%> or %<}%>");
          error_suppress = true;
        }

      substmt = c_parser_omp_structured_block_sequence (parser,
                                                        PRAGMA_OMP_SECTION);
      substmt = build1 (OMP_SECTION, void_type_node, substmt);
      SET_EXPR_LOCATION (substmt, loc);
      add_stmt (substmt);
    }
  c_parser_skip_until_found (parser, CPP_CLOSE_BRACE,
                             "expected %<#pragma omp section%> or %<}%>");

  substmt = pop_stmt_list (stmt);

  stmt = make_node (OMP_SECTIONS);
  SET_EXPR_LOCATION (stmt, sections_loc);
  TREE_TYPE (stmt) = void_type_node;
  OMP_SECTIONS_BODY (stmt) = substmt;

  return add_stmt (stmt);
}

/* OpenMP 2.5:
   # pragma omp sections sections-clause[optseq] newline
     sections-scope

   LOC is the location of the #pragma token.
*/

#define OMP_SECTIONS_CLAUSE_MASK                                \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static tree
c_parser_omp_sections (location_t loc, c_parser *parser,
                       char *p_name, omp_clause_mask mask, tree *cclauses)
{
  tree block, clauses, ret;

  strcat (p_name, " sections");
  mask |= OMP_SECTIONS_CLAUSE_MASK;
  if (cclauses)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT);

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_SECTIONS, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_SECTIONS];
    }

  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_sections_scope (loc, parser);
  if (ret)
    OMP_SECTIONS_CLAUSES (ret) = clauses;
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

/* OpenMP 2.5:
   # pragma omp parallel parallel-clause[optseq] new-line
     structured-block
   # pragma omp parallel for parallel-for-clause[optseq] new-line
     structured-block
   # pragma omp parallel sections parallel-sections-clause[optseq] new-line
     structured-block

   OpenMP 4.0:
   # pragma omp parallel for simd parallel-for-simd-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma token.
*/

#define OMP_PARALLEL_CLAUSE_MASK                                \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEFAULT)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SHARED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COPYIN)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NUM_THREADS)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PROC_BIND))

static tree
c_parser_omp_parallel (location_t loc, c_parser *parser,
                       char *p_name, omp_clause_mask mask, tree *cclauses,
                       bool *if_p)
{
  tree stmt, clauses, block;

  strcat (p_name, " parallel");
  mask |= OMP_PARALLEL_CLAUSE_MASK;
  /* #pragma omp target parallel{, for, for simd} disallow copyin clause.  */
  if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)) != 0
      && (mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DIST_SCHEDULE)) == 0)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COPYIN);

  if (c_parser_next_token_is_keyword (parser, RID_FOR))
    {
      tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
      if (cclauses == NULL)
        cclauses = cclauses_buf;

      c_parser_consume_token (parser);
      if (!flag_openmp)  /* flag_openmp_simd  */
        return c_parser_omp_for (loc, parser, p_name, mask, cclauses, if_p);
      block = c_begin_omp_parallel ();
      tree ret = c_parser_omp_for (loc, parser, p_name, mask, cclauses, if_p);
      stmt
        = c_finish_omp_parallel (loc, cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL],
                                 block);
      if (ret == NULL_TREE)
        return ret;
      OMP_PARALLEL_COMBINED (stmt) = 1;
      return stmt;
    }
  /* When combined with distribute, parallel has to be followed by for.
     #pragma omp target parallel is allowed though.  */
  else if (cclauses
           && (mask & (OMP_CLAUSE_MASK_1
                       << PRAGMA_OMP_CLAUSE_DIST_SCHEDULE)) != 0)
    {
      error_at (loc, "expected %<for%> after %qs", p_name);
      c_parser_skip_to_pragma_eol (parser);
      return NULL_TREE;
    }
  else if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (cclauses == NULL && strcmp (p, "masked") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_masked (loc, parser, p_name, mask, cclauses,
                                        if_p);
          block = c_begin_omp_parallel ();
          tree ret = c_parser_omp_masked (loc, parser, p_name, mask, cclauses,
                                          if_p);
          stmt = c_finish_omp_parallel (loc,
                                        cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL],
                                        block);
          if (ret == NULL)
            return ret;
          /* masked does have just filter clause, but during gimplification
             isn't represented by a gimplification omp context, so for
             #pragma omp parallel masked don't set OMP_PARALLEL_COMBINED,
             so that
             #pragma omp parallel masked
             #pragma omp taskloop simd lastprivate (x)
             isn't confused with
             #pragma omp parallel masked taskloop simd lastprivate (x)  */
          if (OMP_MASKED_COMBINED (ret))
            OMP_PARALLEL_COMBINED (stmt) = 1;
          return stmt;
        }
      else if (cclauses == NULL && strcmp (p, "master") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_master (loc, parser, p_name, mask, cclauses,
                                        if_p);
          block = c_begin_omp_parallel ();
          tree ret = c_parser_omp_master (loc, parser, p_name, mask, cclauses,
                                          if_p);
          stmt = c_finish_omp_parallel (loc,
                                        cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL],
                                        block);
          if (ret == NULL)
            return ret;
          /* master doesn't have any clauses and during gimplification
             isn't represented by a gimplification omp context, so for
             #pragma omp parallel master don't set OMP_PARALLEL_COMBINED,
             so that
             #pragma omp parallel master
             #pragma omp taskloop simd lastprivate (x)
             isn't confused with
             #pragma omp parallel master taskloop simd lastprivate (x)  */
          if (OMP_MASTER_COMBINED (ret))
            OMP_PARALLEL_COMBINED (stmt) = 1;
          return stmt;
        }
      else if (strcmp (p, "loop") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_loop (loc, parser, p_name, mask, cclauses,
                                      if_p);
          block = c_begin_omp_parallel ();
          tree ret = c_parser_omp_loop (loc, parser, p_name, mask, cclauses,
                                        if_p);
          stmt
            = c_finish_omp_parallel (loc,
                                     cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL],
                                     block);
          if (ret == NULL_TREE)
            return ret;
          OMP_PARALLEL_COMBINED (stmt) = 1;
          return stmt;
        }
      else if (!flag_openmp)  /* flag_openmp_simd  */
        {
          c_parser_skip_to_pragma_eol (parser, false);
          return NULL_TREE;
        }
      else if (cclauses == NULL && strcmp (p, "sections") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          block = c_begin_omp_parallel ();
          c_parser_omp_sections (loc, parser, p_name, mask, cclauses);
          stmt = c_finish_omp_parallel (loc,
                                        cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL],
                                        block);
          OMP_PARALLEL_COMBINED (stmt) = 1;
          return stmt;
        }
    }
  else if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_PARALLEL, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_PARALLEL];
    }

  block = c_begin_omp_parallel ();
  parser->omp_attrs_forbidden_p = true;
  c_parser_statement (parser, if_p);
  stmt = c_finish_omp_parallel (loc, clauses, block);

  return stmt;
}

/* OpenMP 2.5:
   # pragma omp single single-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma.
*/

#define OMP_SINGLE_CLAUSE_MASK                                  \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COPYPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static tree
c_parser_omp_single (location_t loc, c_parser *parser, bool *if_p)
{
  tree stmt = make_node (OMP_SINGLE);
  SET_EXPR_LOCATION (stmt, loc);
  TREE_TYPE (stmt) = void_type_node;

  OMP_SINGLE_CLAUSES (stmt)
    = c_parser_omp_all_clauses (parser, OMP_SINGLE_CLAUSE_MASK,
                                "#pragma omp single");
  OMP_SINGLE_BODY (stmt) = c_parser_omp_structured_block (parser, if_p);

  return add_stmt (stmt);
}

/* OpenMP 5.1:
   # pragma omp scope scope-clause[optseq] new-line
     structured-block

   LOC is the location of the #pragma.
*/

#define OMP_SCOPE_CLAUSE_MASK                                   \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static tree
c_parser_omp_scope (location_t loc, c_parser *parser, bool *if_p)
{
  tree stmt = make_node (OMP_SCOPE);
  SET_EXPR_LOCATION (stmt, loc);
  TREE_TYPE (stmt) = void_type_node;

  OMP_SCOPE_CLAUSES (stmt)
    = c_parser_omp_all_clauses (parser, OMP_SCOPE_CLAUSE_MASK,
                                "#pragma omp scope");
  OMP_SCOPE_BODY (stmt) = c_parser_omp_structured_block (parser, if_p);

  return add_stmt (stmt);
}

/* OpenMP 3.0:
   # pragma omp task task-clause[optseq] new-line

   LOC is the location of the #pragma.
*/

#define OMP_TASK_CLAUSE_MASK                                    \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_UNTIED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEFAULT)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SHARED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FINAL)        \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MERGEABLE)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIORITY)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IN_REDUCTION) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DETACH)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_AFFINITY))

static tree
c_parser_omp_task (location_t loc, c_parser *parser, bool *if_p)
{
  tree clauses, block;

  clauses = c_parser_omp_all_clauses (parser, OMP_TASK_CLAUSE_MASK,
                                      "#pragma omp task");

  block = c_begin_omp_task ();
  parser->omp_attrs_forbidden_p = true;
  c_parser_statement (parser, if_p);
  return c_finish_omp_task (loc, clauses, block);
}

/* OpenMP 3.0:
   # pragma omp taskwait new-line

   OpenMP 5.0:
   # pragma omp taskwait taskwait-clause[optseq] new-line
*/

#define OMP_TASKWAIT_CLAUSE_MASK                                        \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)               \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static void
c_parser_omp_taskwait (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);

  tree clauses
    = c_parser_omp_all_clauses (parser, OMP_TASKWAIT_CLAUSE_MASK,
                                "#pragma omp taskwait");

  if (clauses)
    {
      tree stmt = make_node (OMP_TASK);
      TREE_TYPE (stmt) = void_node;
      OMP_TASK_CLAUSES (stmt) = clauses;
      OMP_TASK_BODY (stmt) = NULL_TREE;
      SET_EXPR_LOCATION (stmt, loc);
      add_stmt (stmt);
    }
  else
    c_finish_omp_taskwait (loc);
}

/* OpenMP 3.1:
   # pragma omp taskyield new-line
*/

static void
c_parser_omp_taskyield (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);
  c_parser_skip_to_pragma_eol (parser);

  c_finish_omp_taskyield (loc);
}

/* OpenMP 4.0:
   # pragma omp taskgroup new-line

   OpenMP 5.0:
   # pragma omp taskgroup taskgroup-clause[optseq] new-line
*/

#define OMP_TASKGROUP_CLAUSE_MASK                               \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_TASK_REDUCTION))

static tree
c_parser_omp_taskgroup (location_t loc, c_parser *parser, bool *if_p)
{
  tree clauses = c_parser_omp_all_clauses (parser, OMP_TASKGROUP_CLAUSE_MASK,
                                           "#pragma omp taskgroup");

  tree body = c_parser_omp_structured_block (parser, if_p);
  return c_finish_omp_taskgroup (loc, body, clauses);
}

/* OpenMP 4.0:
   # pragma omp cancel cancel-clause[optseq] new-line

   LOC is the location of the #pragma.
*/

#define OMP_CANCEL_CLAUSE_MASK                                  \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PARALLEL)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FOR)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SECTIONS)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_TASKGROUP)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF))

static void
c_parser_omp_cancel (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;

  c_parser_consume_pragma (parser);
  tree clauses = c_parser_omp_all_clauses (parser, OMP_CANCEL_CLAUSE_MASK,
                                           "#pragma omp cancel");

  c_finish_omp_cancel (loc, clauses);
}

/* OpenMP 4.0:
   # pragma omp cancellation point cancelpt-clause[optseq] new-line

   LOC is the location of the #pragma.
*/

#define OMP_CANCELLATION_POINT_CLAUSE_MASK                      \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PARALLEL)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FOR)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SECTIONS)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_TASKGROUP))

static bool
c_parser_omp_cancellation_point (c_parser *parser, enum pragma_context context)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree clauses;
  bool point_seen = false;

  c_parser_consume_pragma (parser);
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "point") == 0)
        {
          c_parser_consume_token (parser);
          point_seen = true;
        }
    }
  if (!point_seen)
    {
      c_parser_error (parser, "expected %<point%>");
      c_parser_skip_to_pragma_eol (parser);
      return false;
    }

  if (context != pragma_compound)
    {
      if (context == pragma_stmt)
        error_at (loc,
                  "%<#pragma %s%> may only be used in compound statements",
                  "omp cancellation point");
      else
        c_parser_error (parser, "expected declaration specifiers");
      c_parser_skip_to_pragma_eol (parser, false);
      return true;
    }

  clauses
    = c_parser_omp_all_clauses (parser, OMP_CANCELLATION_POINT_CLAUSE_MASK,
                                "#pragma omp cancellation point");

  c_finish_omp_cancellation_point (loc, clauses);
  return true;
}

/* OpenMP 4.0:
   #pragma omp distribute distribute-clause[optseq] new-line
     for-loop  */

#define OMP_DISTRIBUTE_CLAUSE_MASK                              \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DIST_SCHEDULE)\
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ORDER))

static tree
c_parser_omp_distribute (location_t loc, c_parser *parser,
                         char *p_name, omp_clause_mask mask, tree *cclauses,
                         bool *if_p)
{
  tree clauses, block, ret;

  strcat (p_name, " distribute");
  mask |= OMP_DISTRIBUTE_CLAUSE_MASK;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      bool simd = false;
      bool parallel = false;

      if (strcmp (p, "simd") == 0)
        simd = true;
      else
        parallel = strcmp (p, "parallel") == 0;
      if (parallel || simd)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;
          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            {
              if (simd)
                return c_parser_omp_simd (loc, parser, p_name, mask, cclauses,
                                          if_p);
              else
                return c_parser_omp_parallel (loc, parser, p_name, mask,
                                              cclauses, if_p);
            }
          block = c_begin_compound_stmt (true);
          if (simd)
            ret = c_parser_omp_simd (loc, parser, p_name, mask, cclauses,
                                     if_p);
          else
            ret = c_parser_omp_parallel (loc, parser, p_name, mask, cclauses,
                                         if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL)
            return ret;
          ret = make_node (OMP_DISTRIBUTE);
          TREE_TYPE (ret) = void_type_node;
          OMP_FOR_BODY (ret) = block;
          OMP_FOR_CLAUSES (ret) = cclauses[C_OMP_CLAUSE_SPLIT_DISTRIBUTE];
          SET_EXPR_LOCATION (ret, loc);
          add_stmt (ret);
          return ret;
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_DISTRIBUTE, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_DISTRIBUTE];
    }

  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_for_loop (loc, parser, OMP_DISTRIBUTE, clauses, NULL,
                               if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

/* OpenMP 4.0:
   # pragma omp teams teams-clause[optseq] new-line
     structured-block  */

#define OMP_TEAMS_CLAUSE_MASK                                   \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SHARED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NUM_TEAMS)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_THREAD_LIMIT) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEFAULT))

static tree
c_parser_omp_teams (location_t loc, c_parser *parser,
                    char *p_name, omp_clause_mask mask, tree *cclauses,
                    bool *if_p)
{
  tree clauses, block, ret;

  strcat (p_name, " teams");
  mask |= OMP_TEAMS_CLAUSE_MASK;

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "distribute") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_distribute (loc, parser, p_name, mask,
                                            cclauses, if_p);
          block = c_begin_omp_parallel ();
          ret = c_parser_omp_distribute (loc, parser, p_name, mask, cclauses,
                                         if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL)
            return ret;
          clauses = cclauses[C_OMP_CLAUSE_SPLIT_TEAMS];
          ret = make_node (OMP_TEAMS);
          TREE_TYPE (ret) = void_type_node;
          OMP_TEAMS_CLAUSES (ret) = clauses;
          OMP_TEAMS_BODY (ret) = block;
          OMP_TEAMS_COMBINED (ret) = 1;
          SET_EXPR_LOCATION (ret, loc);
          return add_stmt (ret);
        }
      else if (strcmp (p, "loop") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;

          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_loop (loc, parser, p_name, mask, cclauses,
                                      if_p);
          block = c_begin_omp_parallel ();
          ret = c_parser_omp_loop (loc, parser, p_name, mask, cclauses, if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL)
            return ret;
          clauses = cclauses[C_OMP_CLAUSE_SPLIT_TEAMS];
          ret = make_node (OMP_TEAMS);
          TREE_TYPE (ret) = void_type_node;
          OMP_TEAMS_CLAUSES (ret) = clauses;
          OMP_TEAMS_BODY (ret) = block;
          OMP_TEAMS_COMBINED (ret) = 1;
          SET_EXPR_LOCATION (ret, loc);
          return add_stmt (ret);
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_TEAMS, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_TEAMS];
    }

  tree stmt = make_node (OMP_TEAMS);
  TREE_TYPE (stmt) = void_type_node;
  OMP_TEAMS_CLAUSES (stmt) = clauses;
  block = c_begin_omp_parallel ();
  add_stmt (c_parser_omp_structured_block (parser, if_p));
  OMP_TEAMS_BODY (stmt) = c_end_compound_stmt (loc, block, true);
  SET_EXPR_LOCATION (stmt, loc);

  return add_stmt (stmt);
}

/* OpenMP 4.0:
   # pragma omp target data target-data-clause[optseq] new-line
     structured-block  */

#define OMP_TARGET_DATA_CLAUSE_MASK                             \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_USE_DEVICE_PTR) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_USE_DEVICE_ADDR))

static tree
c_parser_omp_target_data (location_t loc, c_parser *parser, bool *if_p)
{
  if (flag_openmp)
    omp_requires_mask
      = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);

  tree clauses
    = c_parser_omp_all_clauses (parser, OMP_TARGET_DATA_CLAUSE_MASK,
                                "#pragma omp target data");
  c_omp_adjust_map_clauses (clauses, false);
  int map_seen = 0;
  for (tree *pc = &clauses; *pc;)
    {
      if (OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_MAP)
        switch (OMP_CLAUSE_MAP_KIND (*pc))
          {
          case GOMP_MAP_TO:
          case GOMP_MAP_ALWAYS_TO:
          case GOMP_MAP_PRESENT_TO:
          case GOMP_MAP_ALWAYS_PRESENT_TO:
          case GOMP_MAP_FROM:
          case GOMP_MAP_ALWAYS_FROM:
          case GOMP_MAP_PRESENT_FROM:
          case GOMP_MAP_ALWAYS_PRESENT_FROM:
          case GOMP_MAP_TOFROM:
          case GOMP_MAP_ALWAYS_TOFROM:
          case GOMP_MAP_PRESENT_TOFROM:
          case GOMP_MAP_ALWAYS_PRESENT_TOFROM:
          case GOMP_MAP_ALLOC:
          case GOMP_MAP_PRESENT_ALLOC:
            map_seen = 3;
            break;
          case GOMP_MAP_FIRSTPRIVATE_POINTER:
          case GOMP_MAP_ALWAYS_POINTER:
          case GOMP_MAP_ATTACH_DETACH:
          case GOMP_MAP_ATTACH:
            break;
          default:
            map_seen |= 1;
            error_at (OMP_CLAUSE_LOCATION (*pc),
                      "%<#pragma omp target data%> with map-type other "
                      "than %<to%>, %<from%>, %<tofrom%> or %<alloc%> "
                      "on %<map%> clause");
            *pc = OMP_CLAUSE_CHAIN (*pc);
            continue;
          }
      else if (OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_USE_DEVICE_PTR
               || OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_USE_DEVICE_ADDR)
        map_seen = 3;
      pc = &OMP_CLAUSE_CHAIN (*pc);
    }

  if (map_seen != 3)
    {
      if (map_seen == 0)
        error_at (loc,
                  "%<#pragma omp target data%> must contain at least "
                  "one %<map%>, %<use_device_ptr%> or %<use_device_addr%> "
                  "clause");
      return NULL_TREE;
    }

  tree stmt = make_node (OMP_TARGET_DATA);
  TREE_TYPE (stmt) = void_type_node;
  OMP_TARGET_DATA_CLAUSES (stmt) = clauses;
  keep_next_level ();
  tree block = c_begin_compound_stmt (true);
  add_stmt (c_parser_omp_structured_block (parser, if_p));
  OMP_TARGET_DATA_BODY (stmt) = c_end_compound_stmt (loc, block, true);

  SET_EXPR_LOCATION (stmt, loc);
  return add_stmt (stmt);
}

/* OpenMP 4.0:
   # pragma omp target update target-update-clause[optseq] new-line */

#define OMP_TARGET_UPDATE_CLAUSE_MASK                           \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FROM)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_TO)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static bool
c_parser_omp_target_update (location_t loc, c_parser *parser,
                            enum pragma_context context)
{
  if (context == pragma_stmt)
    {
      error_at (loc, "%<#pragma %s%> may only be used in compound statements",
                "omp target update");
      c_parser_skip_to_pragma_eol (parser, false);
      return true;
    }

  tree clauses
    = c_parser_omp_all_clauses (parser, OMP_TARGET_UPDATE_CLAUSE_MASK,
                                "#pragma omp target update");
  if (omp_find_clause (clauses, OMP_CLAUSE_TO) == NULL_TREE
      && omp_find_clause (clauses, OMP_CLAUSE_FROM) == NULL_TREE)
    {
      error_at (loc,
                "%<#pragma omp target update%> must contain at least one "
                "%<from%> or %<to%> clauses");
      return false;
    }

  if (flag_openmp)
    omp_requires_mask
      = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);

  tree stmt = make_node (OMP_TARGET_UPDATE);
  TREE_TYPE (stmt) = void_type_node;
  OMP_TARGET_UPDATE_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
  return false;
}

/* OpenMP 4.5:
   # pragma omp target enter data target-data-clause[optseq] new-line  */

#define OMP_TARGET_ENTER_DATA_CLAUSE_MASK                       \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static bool
c_parser_omp_target_enter_data (location_t loc, c_parser *parser,
                                enum pragma_context context)
{
  bool data_seen = false;
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "data") == 0)
        {
          c_parser_consume_token (parser);
          data_seen = true;
        }
    }
  if (!data_seen)
    {
      c_parser_error (parser, "expected %<data%>");
      c_parser_skip_to_pragma_eol (parser);
      return false;
    }

  if (context == pragma_stmt)
    {
      error_at (loc, "%<#pragma %s%> may only be used in compound statements",
                "omp target enter data");
      c_parser_skip_to_pragma_eol (parser, false);
      return true;
    }

  if (flag_openmp)
    omp_requires_mask
      = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);

  tree clauses
    = c_parser_omp_all_clauses (parser, OMP_TARGET_ENTER_DATA_CLAUSE_MASK,
                                "#pragma omp target enter data");
  c_omp_adjust_map_clauses (clauses, false);
  int map_seen = 0;
  for (tree *pc = &clauses; *pc;)
    {
      if (OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_MAP)
        switch (OMP_CLAUSE_MAP_KIND (*pc))
          {
          case GOMP_MAP_TO:
          case GOMP_MAP_ALWAYS_TO:
          case GOMP_MAP_PRESENT_TO:
          case GOMP_MAP_ALWAYS_PRESENT_TO:
          case GOMP_MAP_ALLOC:
          case GOMP_MAP_PRESENT_ALLOC:
            map_seen = 3;
            break;
          case GOMP_MAP_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_TO);
            map_seen = 3;
            break;
          case GOMP_MAP_ALWAYS_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_ALWAYS_TO);
            map_seen = 3;
            break;
          case GOMP_MAP_PRESENT_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_PRESENT_TO);
            map_seen = 3;
            break;
          case GOMP_MAP_ALWAYS_PRESENT_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_ALWAYS_PRESENT_TO);
            map_seen = 3;
            break;
          case GOMP_MAP_FIRSTPRIVATE_POINTER:
          case GOMP_MAP_ALWAYS_POINTER:
          case GOMP_MAP_ATTACH_DETACH:
          case GOMP_MAP_ATTACH:
            break;
          default:
            map_seen |= 1;
            error_at (OMP_CLAUSE_LOCATION (*pc),
                      "%<#pragma omp target enter data%> with map-type other "
                      "than %<to%>, %<tofrom%> or %<alloc%> on %<map%> clause");
            *pc = OMP_CLAUSE_CHAIN (*pc);
            continue;
          }
      pc = &OMP_CLAUSE_CHAIN (*pc);
    }

  if (map_seen != 3)
    {
      if (map_seen == 0)
        error_at (loc,
                  "%<#pragma omp target enter data%> must contain at least "
                  "one %<map%> clause");
      return true;
    }

  tree stmt = make_node (OMP_TARGET_ENTER_DATA);
  TREE_TYPE (stmt) = void_type_node;
  OMP_TARGET_ENTER_DATA_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
  return true;
}

/* OpenMP 4.5:
   # pragma omp target exit data target-data-clause[optseq] new-line  */

#define OMP_TARGET_EXIT_DATA_CLAUSE_MASK                        \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT))

static bool
c_parser_omp_target_exit_data (location_t loc, c_parser *parser,
                               enum pragma_context context)
{
  bool data_seen = false;
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "data") == 0)
        {
          c_parser_consume_token (parser);
          data_seen = true;
        }
    }
  if (!data_seen)
    {
      c_parser_error (parser, "expected %<data%>");
      c_parser_skip_to_pragma_eol (parser);
      return false;
    }

  if (context == pragma_stmt)
    {
      error_at (loc, "%<#pragma %s%> may only be used in compound statements",
                "omp target exit data");
      c_parser_skip_to_pragma_eol (parser, false);
      return true;
    }

  if (flag_openmp)
    omp_requires_mask
      = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);

  tree clauses
    = c_parser_omp_all_clauses (parser, OMP_TARGET_EXIT_DATA_CLAUSE_MASK,
                                "#pragma omp target exit data", false);
  clauses = c_finish_omp_clauses (clauses, C_ORT_OMP_EXIT_DATA);
  c_omp_adjust_map_clauses (clauses, false);
  int map_seen = 0;
  for (tree *pc = &clauses; *pc;)
    {
      if (OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_MAP)
        switch (OMP_CLAUSE_MAP_KIND (*pc))
          {
          case GOMP_MAP_FROM:
          case GOMP_MAP_ALWAYS_FROM:
          case GOMP_MAP_PRESENT_FROM:
          case GOMP_MAP_ALWAYS_PRESENT_FROM:
          case GOMP_MAP_RELEASE:
          case GOMP_MAP_DELETE:
            map_seen = 3;
            break;
          case GOMP_MAP_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_FROM);
            map_seen = 3;
            break;
          case GOMP_MAP_ALWAYS_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_ALWAYS_FROM);
            map_seen = 3;
            break;
          case GOMP_MAP_PRESENT_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_PRESENT_FROM);
            map_seen = 3;
            break;
          case GOMP_MAP_ALWAYS_PRESENT_TOFROM:
            OMP_CLAUSE_SET_MAP_KIND (*pc, GOMP_MAP_ALWAYS_PRESENT_FROM);
            map_seen = 3;
            break;
          case GOMP_MAP_FIRSTPRIVATE_POINTER:
          case GOMP_MAP_ALWAYS_POINTER:
          case GOMP_MAP_ATTACH_DETACH:
          case GOMP_MAP_DETACH:
            break;
          default:
            map_seen |= 1;
            error_at (OMP_CLAUSE_LOCATION (*pc),
                      "%<#pragma omp target exit data%> with map-type other "
                      "than %<from%>, %<tofrom%>, %<release%> or %<delete%> "
                      "on %<map%> clause");
            *pc = OMP_CLAUSE_CHAIN (*pc);
            continue;
          }
      pc = &OMP_CLAUSE_CHAIN (*pc);
    }

  if (map_seen != 3)
    {
      if (map_seen == 0)
        error_at (loc,
                  "%<#pragma omp target exit data%> must contain at least one "
                  "%<map%> clause");
      return true;
    }

  tree stmt = make_node (OMP_TARGET_EXIT_DATA);
  TREE_TYPE (stmt) = void_type_node;
  OMP_TARGET_EXIT_DATA_CLAUSES (stmt) = clauses;
  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);
  return true;
}

/* OpenMP 4.0:
   # pragma omp target target-clause[optseq] new-line
     structured-block  */

#define OMP_TARGET_CLAUSE_MASK                                  \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MAP)          \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEPEND)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOWAIT)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEFAULTMAP)   \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IN_REDUCTION) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_THREAD_LIMIT) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IS_DEVICE_PTR)\
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_HAS_DEVICE_ADDR))

static bool
c_parser_omp_target (c_parser *parser, enum pragma_context context, bool *if_p)
{
  location_t loc = c_parser_peek_token (parser)->location;
  c_parser_consume_pragma (parser);
  tree *pc = NULL, stmt, block;

  if (context != pragma_stmt && context != pragma_compound)
    {
      c_parser_error (parser, "expected declaration specifiers");
      c_parser_skip_to_pragma_eol (parser);
      return false;
    }

  if (flag_openmp)
    omp_requires_mask
      = (enum omp_requires) (omp_requires_mask | OMP_REQUIRES_TARGET_USED);

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      enum tree_code ccode = ERROR_MARK;

      if (strcmp (p, "teams") == 0)
        ccode = OMP_TEAMS;
      else if (strcmp (p, "parallel") == 0)
        ccode = OMP_PARALLEL;
      else if (strcmp (p, "simd") == 0)
        ccode = OMP_SIMD;
      if (ccode != ERROR_MARK)
        {
          tree cclauses[C_OMP_CLAUSE_SPLIT_COUNT];
          char p_name[sizeof ("#pragma omp target teams distribute "
                              "parallel for simd")];

          c_parser_consume_token (parser);
          strcpy (p_name, "#pragma omp target");
          if (!flag_openmp)  /* flag_openmp_simd  */
            {
              tree stmt;
              switch (ccode)
                {
                case OMP_TEAMS:
                  stmt = c_parser_omp_teams (loc, parser, p_name,
                                             OMP_TARGET_CLAUSE_MASK,
                                             cclauses, if_p);
                  break;
                case OMP_PARALLEL:
                  stmt = c_parser_omp_parallel (loc, parser, p_name,
                                                OMP_TARGET_CLAUSE_MASK,
                                                cclauses, if_p);
                  break;
                case OMP_SIMD:
                  stmt = c_parser_omp_simd (loc, parser, p_name,
                                            OMP_TARGET_CLAUSE_MASK,
                                            cclauses, if_p);
                  break;
                default:
                  gcc_unreachable ();
                }
              return stmt != NULL_TREE;
            }
          keep_next_level ();
          tree block = c_begin_compound_stmt (true), ret;
          switch (ccode)
            {
            case OMP_TEAMS:
              ret = c_parser_omp_teams (loc, parser, p_name,
                                        OMP_TARGET_CLAUSE_MASK, cclauses,
                                        if_p);
              break;
            case OMP_PARALLEL:
              ret = c_parser_omp_parallel (loc, parser, p_name,
                                           OMP_TARGET_CLAUSE_MASK, cclauses,
                                           if_p);
              break;
            case OMP_SIMD:
              ret = c_parser_omp_simd (loc, parser, p_name,
                                       OMP_TARGET_CLAUSE_MASK, cclauses,
                                       if_p);
              break;
            default:
              gcc_unreachable ();
            }
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL_TREE)
            return false;
          if (ccode == OMP_TEAMS)
            /* For combined target teams, ensure the num_teams and
               thread_limit clause expressions are evaluated on the host,
               before entering the target construct.  */
            for (tree c = cclauses[C_OMP_CLAUSE_SPLIT_TEAMS];
                 c; c = OMP_CLAUSE_CHAIN (c))
              if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_NUM_TEAMS
                  || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_THREAD_LIMIT)
                for (int i = 0;
                     i <= (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_NUM_TEAMS); ++i)
                  if (OMP_CLAUSE_OPERAND (c, i)
                      && TREE_CODE (OMP_CLAUSE_OPERAND (c, i)) != INTEGER_CST)
                    {
                      tree expr = OMP_CLAUSE_OPERAND (c, i);
                      tree tmp = create_tmp_var_raw (TREE_TYPE (expr));
                      expr = build4 (TARGET_EXPR, TREE_TYPE (expr), tmp,
                                     expr, NULL_TREE, NULL_TREE);
                      add_stmt (expr);
                      OMP_CLAUSE_OPERAND (c, i) = expr;
                      tree tc = build_omp_clause (OMP_CLAUSE_LOCATION (c),
                                                  OMP_CLAUSE_FIRSTPRIVATE);
                      OMP_CLAUSE_DECL (tc) = tmp;
                      OMP_CLAUSE_CHAIN (tc)
                        = cclauses[C_OMP_CLAUSE_SPLIT_TARGET];
                      cclauses[C_OMP_CLAUSE_SPLIT_TARGET] = tc;
                    }
          tree stmt = make_node (OMP_TARGET);
          TREE_TYPE (stmt) = void_type_node;
          OMP_TARGET_CLAUSES (stmt) = cclauses[C_OMP_CLAUSE_SPLIT_TARGET];
          c_omp_adjust_map_clauses (OMP_TARGET_CLAUSES (stmt), true);
          OMP_TARGET_BODY (stmt) = block;
          OMP_TARGET_COMBINED (stmt) = 1;
          SET_EXPR_LOCATION (stmt, loc);
          add_stmt (stmt);
          pc = &OMP_TARGET_CLAUSES (stmt);
          goto check_clauses;
        }
      else if (!flag_openmp)  /* flag_openmp_simd  */
        {
          c_parser_skip_to_pragma_eol (parser, false);
          return false;
        }
      else if (strcmp (p, "data") == 0)
        {
          c_parser_consume_token (parser);
          c_parser_omp_target_data (loc, parser, if_p);
          return true;
        }
      else if (strcmp (p, "enter") == 0)
        {
          c_parser_consume_token (parser);
          return c_parser_omp_target_enter_data (loc, parser, context);
        }
      else if (strcmp (p, "exit") == 0)
        {
          c_parser_consume_token (parser);
          return c_parser_omp_target_exit_data (loc, parser, context);
        }
      else if (strcmp (p, "update") == 0)
        {
          c_parser_consume_token (parser);
          return c_parser_omp_target_update (loc, parser, context);
        }
    }
  if (!flag_openmp) /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return false;
    }

  stmt = make_node (OMP_TARGET);
  TREE_TYPE (stmt) = void_type_node;

  OMP_TARGET_CLAUSES (stmt)
    = c_parser_omp_all_clauses (parser, OMP_TARGET_CLAUSE_MASK,
                                "#pragma omp target", false);
  for (tree c = OMP_TARGET_CLAUSES (stmt); c; c = OMP_CLAUSE_CHAIN (c))
    if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_IN_REDUCTION)
      {
        tree nc = build_omp_clause (OMP_CLAUSE_LOCATION (c), OMP_CLAUSE_MAP);
        OMP_CLAUSE_DECL (nc) = OMP_CLAUSE_DECL (c);
        OMP_CLAUSE_SET_MAP_KIND (nc, GOMP_MAP_ALWAYS_TOFROM);
        OMP_CLAUSE_CHAIN (nc) = OMP_CLAUSE_CHAIN (c);
        OMP_CLAUSE_CHAIN (c) = nc;
      }
  OMP_TARGET_CLAUSES (stmt)
    = c_finish_omp_clauses (OMP_TARGET_CLAUSES (stmt), C_ORT_OMP_TARGET);
  c_omp_adjust_map_clauses (OMP_TARGET_CLAUSES (stmt), true);

  pc = &OMP_TARGET_CLAUSES (stmt);
  keep_next_level ();
  block = c_begin_compound_stmt (true);
  add_stmt (c_parser_omp_structured_block (parser, if_p));
  OMP_TARGET_BODY (stmt) = c_end_compound_stmt (loc, block, true);

  SET_EXPR_LOCATION (stmt, loc);
  add_stmt (stmt);

check_clauses:
  while (*pc)
    {
      if (OMP_CLAUSE_CODE (*pc) == OMP_CLAUSE_MAP)
        switch (OMP_CLAUSE_MAP_KIND (*pc))
          {
          case GOMP_MAP_TO:
          case GOMP_MAP_ALWAYS_TO:
          case GOMP_MAP_PRESENT_TO:
          case GOMP_MAP_ALWAYS_PRESENT_TO:
          case GOMP_MAP_FROM:
          case GOMP_MAP_ALWAYS_FROM:
          case GOMP_MAP_PRESENT_FROM:
          case GOMP_MAP_ALWAYS_PRESENT_FROM:
          case GOMP_MAP_TOFROM:
          case GOMP_MAP_ALWAYS_TOFROM:
          case GOMP_MAP_PRESENT_TOFROM:
          case GOMP_MAP_ALWAYS_PRESENT_TOFROM:
          case GOMP_MAP_ALLOC:
          case GOMP_MAP_PRESENT_ALLOC:
          case GOMP_MAP_FIRSTPRIVATE_POINTER:
          case GOMP_MAP_ALWAYS_POINTER:
          case GOMP_MAP_POINTER:
          case GOMP_MAP_ATTACH_DETACH:
          case GOMP_MAP_ATTACH:
            break;
          default:
            error_at (OMP_CLAUSE_LOCATION (*pc),
                      "%<#pragma omp target%> with map-type other "
                      "than %<to%>, %<from%>, %<tofrom%> or %<alloc%> "
                      "on %<map%> clause");
            *pc = OMP_CLAUSE_CHAIN (*pc);
            continue;
          }
      pc = &OMP_CLAUSE_CHAIN (*pc);
    }
  cfun->has_omp_target = true;
  return true;
}

/* OpenMP 4.0:
   # pragma omp declare simd declare-simd-clauses[optseq] new-line

   OpenMP 5.0:
   # pragma omp declare variant (identifier) match(context-selector) new-line
   */

#define OMP_DECLARE_SIMD_CLAUSE_MASK                            \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SIMDLEN)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINEAR)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALIGNED)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_UNIFORM)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_INBRANCH)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOTINBRANCH))

static void
c_parser_omp_declare_simd (c_parser *parser, enum pragma_context context)
{
  c_token *token = c_parser_peek_token (parser);
  gcc_assert (token->type == CPP_NAME);
  tree kind = token->value;
  gcc_assert (strcmp (IDENTIFIER_POINTER (kind), "simd") == 0
              || strcmp (IDENTIFIER_POINTER (kind), "variant") == 0);

  auto_vec<c_token> clauses;
  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      c_token *token = c_parser_peek_token (parser);
      if (token->type == CPP_EOF)
        {
          c_parser_skip_to_pragma_eol (parser);
          return;
        }
      clauses.safe_push (*token);
      c_parser_consume_token (parser);
    }
  clauses.safe_push (*c_parser_peek_token (parser));
  c_parser_skip_to_pragma_eol (parser);

  while (c_parser_next_token_is (parser, CPP_PRAGMA))
    {
      if (c_parser_peek_token (parser)->pragma_kind != PRAGMA_OMP_DECLARE
          || c_parser_peek_2nd_token (parser)->type != CPP_NAME
          || c_parser_peek_2nd_token (parser)->value != kind)
        {
          error ("%<#pragma omp declare %s%> must be followed by "
                 "function declaration or definition or another "
                 "%<#pragma omp declare %s%>",
                 IDENTIFIER_POINTER (kind), IDENTIFIER_POINTER (kind));
          return;
        }
      c_parser_consume_pragma (parser);
      while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
        {
          c_token *token = c_parser_peek_token (parser);
          if (token->type == CPP_EOF)
            {
              c_parser_skip_to_pragma_eol (parser);
              return;
            }
          clauses.safe_push (*token);
          c_parser_consume_token (parser);
        }
      clauses.safe_push (*c_parser_peek_token (parser));
      c_parser_skip_to_pragma_eol (parser);
    }

  /* Make sure nothing tries to read past the end of the tokens.  */
  c_token eof_token;
  memset (&eof_token, 0, sizeof (eof_token));
  eof_token.type = CPP_EOF;
  clauses.safe_push (eof_token);
  clauses.safe_push (eof_token);

  switch (context)
    {
    case pragma_external:
      if (c_parser_next_token_is (parser, CPP_KEYWORD)
          && c_parser_peek_token (parser)->keyword == RID_EXTENSION)
        {
          int ext = disable_extension_diagnostics ();
          do
            c_parser_consume_token (parser);
          while (c_parser_next_token_is (parser, CPP_KEYWORD)
                 && c_parser_peek_token (parser)->keyword == RID_EXTENSION);
          c_parser_declaration_or_fndef (parser, true, true, true, false, true,
                                         NULL, &clauses);
          restore_extension_diagnostics (ext);
        }
      else
        c_parser_declaration_or_fndef (parser, true, true, true, false, true,
                                       NULL, &clauses);
      break;
    case pragma_struct:
    case pragma_param:
    case pragma_stmt:
      error ("%<#pragma omp declare %s%> must be followed by "
             "function declaration or definition",
             IDENTIFIER_POINTER (kind));
      break;
    case pragma_compound:
      bool have_std_attrs;
      tree std_attrs;
      have_std_attrs = c_parser_nth_token_starts_std_attributes (parser, 1);
      if (have_std_attrs)
        std_attrs = c_parser_std_attribute_specifier_sequence (parser);
      else
        std_attrs = NULL_TREE;
      if (c_parser_next_token_is (parser, CPP_KEYWORD)
          && c_parser_peek_token (parser)->keyword == RID_EXTENSION)
        {
          int ext = disable_extension_diagnostics ();
          do
            c_parser_consume_token (parser);
          while (c_parser_next_token_is (parser, CPP_KEYWORD)
                 && c_parser_peek_token (parser)->keyword == RID_EXTENSION);
          if (c_parser_next_tokens_start_declaration (parser)
              || c_parser_nth_token_starts_std_attributes (parser, 1))
            {
              c_parser_declaration_or_fndef (parser, true, true, true, true,
                                             true, NULL, &clauses,
                                             have_std_attrs, std_attrs);
              restore_extension_diagnostics (ext);
              break;
            }
          restore_extension_diagnostics (ext);
        }
      else if (c_parser_next_tokens_start_declaration (parser))
        {
          c_parser_declaration_or_fndef (parser, true, true, true, true, true,
                                         NULL, &clauses, have_std_attrs,
                                         std_attrs);
          break;
        }
      error ("%<#pragma omp declare %s%> must be followed by "
             "function declaration or definition",
             IDENTIFIER_POINTER (kind));
      break;
    default:
      gcc_unreachable ();
    }
}

/* OpenMP 5.0:

   trait-selector:
     trait-selector-name[([trait-score:]trait-property[,trait-property[,...]])]

   trait-score:
     score(score-expression)

   Note that this function returns a list of trait selectors for the
   trait-selector-set SET.  */

static tree
c_parser_omp_context_selector (c_parser *parser, enum omp_tss_code set,
                               tree parms)
{
  tree ret = NULL_TREE;
  do
    {
      tree selector;
      if (c_parser_next_token_is (parser, CPP_KEYWORD)
          || c_parser_next_token_is (parser, CPP_NAME))
        selector = c_parser_peek_token (parser)->value;
      else
        {
          c_parser_error (parser, "expected trait selector name");
          return error_mark_node;
        }
      enum omp_ts_code sel
        = omp_lookup_ts_code (set, IDENTIFIER_POINTER (selector));

      if (sel == OMP_TRAIT_INVALID)
        {
          /* Per the spec, "Implementations can ignore specified selectors
             that are not those described in this section"; however, we
             must record such selectors because they cause match failures.  */
          warning_at (c_parser_peek_token (parser)->location, OPT_Wopenmp,
                      "unknown selector %qs for context selector set %qs",
                      IDENTIFIER_POINTER (selector),  omp_tss_map[set]);
          c_parser_consume_token (parser);
          ret = make_trait_selector (sel, NULL_TREE, NULL_TREE, ret);
          if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
            c_parser_balanced_token_sequence (parser);
          if (c_parser_next_token_is (parser, CPP_COMMA))
            {
              c_parser_consume_token (parser);
              continue;
            }
          else
            break;
        }

      c_parser_consume_token (parser);

      tree properties = NULL_TREE;
      tree scoreval = NULL_TREE;
      enum omp_tp_type property_kind = omp_ts_map[sel].tp_type;
      bool allow_score = omp_ts_map[sel].allow_score;
      tree t;

      if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
        {
          if (property_kind == OMP_TRAIT_PROPERTY_NONE)
            {
              error_at (c_parser_peek_token (parser)->location,
                        "selector %qs does not accept any properties",
                        IDENTIFIER_POINTER (selector));
              return error_mark_node;
            }

          matching_parens parens;
          parens.require_open (parser);

          c_token *token = c_parser_peek_token (parser);
          if (c_parser_next_token_is (parser, CPP_NAME)
              && strcmp (IDENTIFIER_POINTER (token->value), "score") == 0
              && c_parser_peek_2nd_token (parser)->type == CPP_OPEN_PAREN)
            {
              c_parser_consume_token (parser);

              matching_parens parens2;
              parens2.require_open (parser);
              tree score = c_parser_expr_no_commas (parser, NULL).value;
              parens2.skip_until_found_close (parser);
              c_parser_require (parser, CPP_COLON, "expected %<:%>");
              if (!allow_score)
                error_at (token->location,
                          "%<score%> cannot be specified in traits "
                          "in the %qs trait-selector-set",
                          omp_tss_map[set]);
              else if (score != error_mark_node)
                {
                  mark_exp_read (score);
                  score = c_fully_fold (score, false, NULL);
                  if (!INTEGRAL_TYPE_P (TREE_TYPE (score))
                      || TREE_CODE (score) != INTEGER_CST)
                    error_at (token->location, "%<score%> argument must "
                              "be constant integer expression");
                  else if (tree_int_cst_sgn (score) < 0)
                    error_at (token->location, "%<score%> argument must "
                              "be non-negative");
                  else
                    scoreval = score;
                }
              token = c_parser_peek_token (parser);
            }

          switch (property_kind)
            {
            case OMP_TRAIT_PROPERTY_ID:
              if (c_parser_next_token_is (parser, CPP_KEYWORD)
                  || c_parser_next_token_is (parser, CPP_NAME))
                {
                  tree prop = c_parser_peek_token (parser)->value;
                  c_parser_consume_token (parser);
                  properties = make_trait_property (prop, NULL_TREE,
                                                    properties);
                }
              else
                {
                  c_parser_error (parser, "expected identifier");
                  return error_mark_node;
                }
              break;
            case OMP_TRAIT_PROPERTY_NAME_LIST:
              do
                {
                  tree prop = OMP_TP_NAMELIST_NODE;
                  tree value = NULL_TREE;
                  if (c_parser_next_token_is (parser, CPP_KEYWORD)
                      || c_parser_next_token_is (parser, CPP_NAME))
                    {
                      value = c_parser_peek_token (parser)->value;
                      c_parser_consume_token (parser);
                    }
                  else if (c_parser_next_token_is (parser, CPP_STRING))
                    value = c_parser_string_literal (parser, false,
                                                     false).value;
                  else
                    {
                      c_parser_error (parser, "expected identifier or "
                                              "string literal");
                      return error_mark_node;
                    }

                  properties = make_trait_property (prop, value, properties);

                  if (c_parser_next_token_is (parser, CPP_COMMA))
                    c_parser_consume_token (parser);
                  else
                    break;
                }
              while (1);
              break;
            case OMP_TRAIT_PROPERTY_EXPR:
              t = c_parser_expr_no_commas (parser, NULL).value;
              if (t != error_mark_node)
                {
                  mark_exp_read (t);
                  t = c_fully_fold (t, false, NULL);
                  /* FIXME: this is bogus, both device_num and
                     condition selectors allow arbitrary expressions.  */
                  if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
                      || !tree_fits_shwi_p (t))
                    error_at (token->location, "property must be "
                              "constant integer expression");
                  else
                    properties = make_trait_property (NULL_TREE, t,
                                                      properties);
                }
              else
                return error_mark_node;
              break;
            case OMP_TRAIT_PROPERTY_CLAUSE_LIST:
              if (sel == OMP_TRAIT_CONSTRUCT_SIMD)
                {
                  if (parms == NULL_TREE)
                    {
                      error_at (token->location, "properties for %<simd%> "
                                "selector may not be specified in "
                                "%<metadirective%>");
                      return error_mark_node;
                    }
                  tree c;
                  c = c_parser_omp_all_clauses (parser,
                                                OMP_DECLARE_SIMD_CLAUSE_MASK,
                                                "simd", true, 2);
                  c = c_omp_declare_simd_clauses_to_numbers (parms
                                                             == error_mark_node
                                                             ? NULL_TREE : parms,
                                                             c);
                  properties = c;
                }
              else if (sel == OMP_TRAIT_IMPLEMENTATION_REQUIRES)
                {
                  /* FIXME: The "requires" selector was added in OpenMP 5.1.
                     Currently only the now-deprecated syntax
                     from OpenMP 5.0 is supported.  */
                  sorry_at (token->location,
                            "%<requires%> selector is not supported yet");
                  return error_mark_node;
                }
              else
                gcc_unreachable ();
              break;
            default:
              gcc_unreachable ();
            }

          parens.skip_until_found_close (parser);
          properties = nreverse (properties);
        }
      else if (property_kind != OMP_TRAIT_PROPERTY_NONE
               && property_kind != OMP_TRAIT_PROPERTY_CLAUSE_LIST
               && property_kind != OMP_TRAIT_PROPERTY_EXTENSION)
        {
          c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>");
          return error_mark_node;
        }

      ret = make_trait_selector (sel, scoreval, properties, ret);

      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  while (1);

  return nreverse (ret);
}

/* OpenMP 5.0:

   trait-set-selector[,trait-set-selector[,...]]

   trait-set-selector:
     trait-set-selector-name = { trait-selector[, trait-selector[, ...]] }

   trait-set-selector-name:
     constructor
     device
     implementation
     user  */

static tree
c_parser_omp_context_selector_specification (c_parser *parser, tree parms)
{
  tree ret = NULL_TREE;
  do
    {
      const char *setp = "";
      if (c_parser_next_token_is (parser, CPP_NAME))
        setp = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      enum omp_tss_code set = omp_lookup_tss_code (setp);

      if (set == OMP_TRAIT_SET_INVALID)
        {
          c_parser_error (parser, "expected context selector set name");
          return error_mark_node;
        }

      c_parser_consume_token (parser);

      if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
        return error_mark_node;

      matching_braces braces;
      if (!braces.require_open (parser))
        return error_mark_node;

      tree selectors = c_parser_omp_context_selector (parser, set, parms);
      if (selectors == error_mark_node)
        ret = error_mark_node;
      else if (ret != error_mark_node)
        ret = make_trait_set_selector (set, selectors, ret);

      braces.skip_until_found_close (parser);

      if (c_parser_next_token_is (parser, CPP_COMMA))
        c_parser_consume_token (parser);
      else
        break;
    }
  while (1);

  if (ret == error_mark_node)
    return ret;
  return nreverse (ret);
}

/* Finalize #pragma omp declare variant after FNDECL has been parsed, and put
   that into "omp declare variant base" attribute.  */

static void
c_finish_omp_declare_variant (c_parser *parser, tree fndecl, tree parms)
{
  matching_parens parens;
  if (!parens.require_open (parser))
    {
     fail:
      c_parser_skip_to_pragma_eol (parser, false);
      return;
    }

  if (c_parser_next_token_is_not (parser, CPP_NAME)
      || c_parser_peek_token (parser)->id_kind != C_ID_ID)
    {
      c_parser_error (parser, "expected identifier");
      goto fail;
    }

  c_token *token = c_parser_peek_token (parser);
  tree variant = lookup_name (token->value);

  if (variant == NULL_TREE)
    {
      undeclared_variable (token->location, token->value);
      variant = error_mark_node;
    }

  c_parser_consume_token (parser);

  parens.require_close (parser);

  if (c_parser_next_token_is (parser, CPP_COMMA)
      && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
    c_parser_consume_token (parser);

  const char *clause = "";
  location_t match_loc = c_parser_peek_token (parser)->location;
  if (c_parser_next_token_is (parser, CPP_NAME))
    clause = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp (clause, "match"))
    {
      c_parser_error (parser, "expected %<match%>");
      goto fail;
    }

  c_parser_consume_token (parser);

  if (!parens.require_open (parser))
    goto fail;

  if (parms == NULL_TREE)
    parms = error_mark_node;

  tree ctx = c_parser_omp_context_selector_specification (parser, parms);
  if (ctx == error_mark_node)
    goto fail;
  ctx = omp_check_context_selector (match_loc, ctx);
  if (ctx != error_mark_node && variant != error_mark_node)
    {
      if (TREE_CODE (variant) != FUNCTION_DECL)
        {
          error_at (token->location, "variant %qD is not a function", variant);
          variant = error_mark_node;
        }
      else if (!omp_get_context_selector (ctx, OMP_TRAIT_SET_CONSTRUCT,
                                          OMP_TRAIT_CONSTRUCT_SIMD)
               && !comptypes (TREE_TYPE (fndecl), TREE_TYPE (variant)))
        {
          error_at (token->location, "variant %qD and base %qD have "
                                     "incompatible types", variant, fndecl);
          variant = error_mark_node;
        }
      else if (fndecl_built_in_p (variant)
               && (strncmp (IDENTIFIER_POINTER (DECL_NAME (variant)),
                            "__builtin_", strlen ("__builtin_")) == 0
                   || strncmp (IDENTIFIER_POINTER (DECL_NAME (variant)),
                               "__sync_", strlen ("__sync_")) == 0
                   || strncmp (IDENTIFIER_POINTER (DECL_NAME (variant)),
                               "__atomic_", strlen ("__atomic_")) == 0))
        {
          error_at (token->location, "variant %qD is a built-in", variant);
          variant = error_mark_node;
        }
      if (variant != error_mark_node)
        {
          C_DECL_USED (variant) = 1;
          tree construct
            = omp_get_context_selector_list (ctx, OMP_TRAIT_SET_CONSTRUCT);
          omp_mark_declare_variant (match_loc, variant, construct);
          if (omp_context_selector_matches (ctx))
            {
              tree attr
                = tree_cons (get_identifier ("omp declare variant base"),
                             build_tree_list (variant, ctx),
                             DECL_ATTRIBUTES (fndecl));
              DECL_ATTRIBUTES (fndecl) = attr;
            }
        }
    }

  parens.require_close (parser);
  c_parser_skip_to_pragma_eol (parser);
}

/* Finalize #pragma omp declare simd or #pragma omp declare variant
   clauses after FNDECL has been parsed, and put that into "omp declare simd"
   or "omp declare variant base" attribute.  */

static void
c_finish_omp_declare_simd (c_parser *parser, tree fndecl, tree parms,
                           vec<c_token> *pclauses)
{
  vec<c_token> &clauses = *pclauses;

  /* Normally first token is CPP_NAME "simd" or "variant".  CPP_EOF there
     indicates error has been reported and CPP_PRAGMA that
     c_finish_omp_declare_simd has already processed the tokens.  */
  if (clauses.exists () && clauses[0].type == CPP_EOF)
    return;
  const char *kind = "simd";
  if (clauses.exists ()
      && (clauses[0].type == CPP_NAME || clauses[0].type == CPP_PRAGMA))
    kind = IDENTIFIER_POINTER (clauses[0].value);
  gcc_assert (strcmp (kind, "simd") == 0 || strcmp (kind, "variant") == 0);
  if (fndecl == NULL_TREE || TREE_CODE (fndecl) != FUNCTION_DECL)
    {
      error ("%<#pragma omp declare %s%> not immediately followed by "
             "a function declaration or definition", kind);
      clauses[0].type = CPP_EOF;
      return;
    }
  if (clauses.exists () && clauses[0].type != CPP_NAME)
    {
      error_at (DECL_SOURCE_LOCATION (fndecl),
                "%<#pragma omp declare %s%> not immediately followed by "
                "a single function declaration or definition", kind);
      clauses[0].type = CPP_EOF;
      return;
    }

  if (parms == NULL_TREE)
    parms = DECL_ARGUMENTS (fndecl);

  unsigned int tokens_avail = parser->tokens_avail;
  gcc_assert (parser->tokens == &parser->tokens_buf[0]);

  parser->tokens = clauses.address ();
  parser->tokens_avail = clauses.length ();
  
  /* c_parser_omp_declare_simd pushed 2 extra CPP_EOF tokens at the end.  */
  while (parser->tokens_avail > 3)
    {
      c_token *token = c_parser_peek_token (parser);
      gcc_assert (token->type == CPP_NAME);
      kind = IDENTIFIER_POINTER (token->value);
      c_parser_consume_token (parser);
      parser->in_pragma = true;

      if (strcmp (kind, "simd") == 0)
        {
          tree c;
          c = c_parser_omp_all_clauses (parser, OMP_DECLARE_SIMD_CLAUSE_MASK,
                                        "#pragma omp declare simd");
          c = c_omp_declare_simd_clauses_to_numbers (parms, c);
          if (c != NULL_TREE)
            c = tree_cons (NULL_TREE, c, NULL_TREE);
          c = build_tree_list (get_identifier ("omp declare simd"), c);
          TREE_CHAIN (c) = DECL_ATTRIBUTES (fndecl);
          DECL_ATTRIBUTES (fndecl) = c;
        }
      else
        {
          gcc_assert (strcmp (kind, "variant") == 0);
          c_finish_omp_declare_variant (parser, fndecl, parms);
        }
    }

  parser->tokens = &parser->tokens_buf[0];
  parser->tokens_avail = tokens_avail;
  if (clauses.exists ())
    clauses[0].type = CPP_PRAGMA;
}

/* D should be C_TOKEN_VEC from omp::decl attribute.  If it contains
   a threadprivate, groupprivate, allocate or declare target directive,
   return true and parse it for DECL.  */

bool
c_maybe_parse_omp_decl (tree decl, tree d)
{
  gcc_assert (TREE_CODE (d) == C_TOKEN_VEC);
  vec<c_token, va_gc> *toks = C_TOKEN_VEC_TOKENS (d);
  c_token *first = toks->address ();
  c_token *last = first + toks->length ();
  const char *directive[3] = {};
  for (int j = 0; j < 3; j++)
    {
      tree id = NULL_TREE;
      if (first + j == last)
        break;
      if (first[j].type == CPP_NAME)
        id = first[j].value;
      else if (first[j].type == CPP_KEYWORD)
        id = ridpointers[(int) first[j].keyword];
      else
        break;
      directive[j] = IDENTIFIER_POINTER (id);
    }
  const c_omp_directive *dir = NULL;
  if (directive[0])
    dir = c_omp_categorize_directive (directive[0], directive[1],
                                      directive[2]);
  if (dir == NULL)
    {
      error_at (first->location,
                "unknown OpenMP directive name in "
                "%qs attribute argument", "omp::decl");
      return false;
    }
  if (dir->id != PRAGMA_OMP_THREADPRIVATE
      /* && dir->id != PRAGMA_OMP_GROUPPRIVATE */
      && dir->id != PRAGMA_OMP_ALLOCATE
      && (dir->id != PRAGMA_OMP_DECLARE
          || strcmp (directive[1], "target") != 0))
    return false;

  if (!flag_openmp && !dir->simd)
    return true;

  c_parser *parser = the_parser;
  unsigned int tokens_avail = parser->tokens_avail;
  gcc_assert (parser->tokens == &parser->tokens_buf[0]);
  toks = NULL;
  vec_safe_reserve (toks, last - first + 2, true);
  c_token tok = {};
  tok.type = CPP_PRAGMA;
  tok.keyword = RID_MAX;
  tok.pragma_kind = pragma_kind (dir->id);
  tok.location = first->location;
  toks->quick_push (tok);
  while (++first < last)
    toks->quick_push (*first);
  tok = {};
  tok.type = CPP_PRAGMA_EOL;
  tok.keyword = RID_MAX;
  tok.location = last[-1].location;
  toks->quick_push (tok);
  tok = {};
  tok.type = CPP_EOF;
  tok.keyword = RID_MAX;
  tok.location = last[-1].location;
  tok.flags = tokens_avail;
  toks->quick_push (tok);
  parser->in_omp_decl_attribute = decl;
  parser->tokens = toks->address ();
  parser->tokens_avail = toks->length ();
  parser->in_omp_attribute_pragma = toks;
  c_parser_pragma (parser, pragma_external, NULL);
  parser->in_omp_decl_attribute = NULL_TREE;
  return true;
}

/* OpenMP 4.0:
   # pragma omp declare target new-line
   declarations and definitions
   # pragma omp end declare target new-line

   OpenMP 4.5:
   # pragma omp declare target ( extended-list ) new-line

   # pragma omp declare target declare-target-clauses[seq] new-line  */

#define OMP_DECLARE_TARGET_CLAUSE_MASK                          \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_TO)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ENTER)        \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LINK)         \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE_TYPE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_INDIRECT))

static void
c_parser_omp_declare_target (c_parser *parser)
{
  tree clauses = NULL_TREE;
  int device_type = 0;
  bool indirect = false;
  bool only_device_type_or_indirect = true;
  if (c_parser_next_token_is (parser, CPP_NAME)
      || (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME))
    clauses = c_parser_omp_all_clauses (parser, OMP_DECLARE_TARGET_CLAUSE_MASK,
                                        "#pragma omp declare target");
  else if (parser->in_omp_decl_attribute
           || c_parser_next_token_is (parser, CPP_OPEN_PAREN))
    {
      clauses = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ENTER,
                                              clauses);
      clauses = c_finish_omp_clauses (clauses, C_ORT_OMP);
      c_parser_skip_to_pragma_eol (parser);
    }
  else
    {
      bool attr_syntax = parser->in_omp_attribute_pragma != NULL;
      c_parser_skip_to_pragma_eol (parser);
      c_omp_declare_target_attr attr = { attr_syntax, -1, 0 };
      vec_safe_push (current_omp_declare_target_attribute, attr);
      return;
    }
  for (tree c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
    {
      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEVICE_TYPE)
        device_type |= OMP_CLAUSE_DEVICE_TYPE_KIND (c);
      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_INDIRECT)
        indirect |= !integer_zerop (OMP_CLAUSE_INDIRECT_EXPR (c));
    }
  for (tree c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
    {
      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEVICE_TYPE
          || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_INDIRECT)
        continue;
      tree t = OMP_CLAUSE_DECL (c), id;
      tree at1 = lookup_attribute ("omp declare target", DECL_ATTRIBUTES (t));
      tree at2 = lookup_attribute ("omp declare target link",
                                   DECL_ATTRIBUTES (t));
      only_device_type_or_indirect = false;
      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LINK)
        {
          id = get_identifier ("omp declare target link");
          std::swap (at1, at2);
        }
      else
        id = get_identifier ("omp declare target");
      if (at2)
        {
          if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_ENTER)
            error_at (OMP_CLAUSE_LOCATION (c),
                      "%qD specified both in declare target %<link%> and %qs"
                      " clauses", t, OMP_CLAUSE_ENTER_TO (c) ? "to" : "enter");
          else
            error_at (OMP_CLAUSE_LOCATION (c),
                      "%qD specified both in declare target %<link%> and "
                      "%<to%> or %<enter%> clauses", t);
          continue;
        }
      if (!at1)
        {
          DECL_ATTRIBUTES (t) = tree_cons (id, NULL_TREE, DECL_ATTRIBUTES (t));
          if (TREE_CODE (t) != FUNCTION_DECL && !is_global_var (t))
            continue;

          symtab_node *node = symtab_node::get (t);
          if (node != NULL)
            {
              node->offloadable = 1;
              if (ENABLE_OFFLOADING)
                {
                  g->have_offload = true;
                  if (is_a <varpool_node *> (node))
                    vec_safe_push (offload_vars, t);
                }
            }
        }
      if (TREE_CODE (t) != FUNCTION_DECL)
        continue;
      if ((device_type & OMP_CLAUSE_DEVICE_TYPE_HOST) != 0)
        {
          tree at3 = lookup_attribute ("omp declare target host",
                                       DECL_ATTRIBUTES (t));
          if (at3 == NULL_TREE)
            {
              id = get_identifier ("omp declare target host");
              DECL_ATTRIBUTES (t)
                = tree_cons (id, NULL_TREE, DECL_ATTRIBUTES (t));
            }
        }
      if ((device_type & OMP_CLAUSE_DEVICE_TYPE_NOHOST) != 0)
        {
          tree at3 = lookup_attribute ("omp declare target nohost",
                                       DECL_ATTRIBUTES (t));
          if (at3 == NULL_TREE)
            {
              id = get_identifier ("omp declare target nohost");
              DECL_ATTRIBUTES (t)
                = tree_cons (id, NULL_TREE, DECL_ATTRIBUTES (t));
            }
        }
      if (indirect)
        {
          tree at4 = lookup_attribute ("omp declare target indirect",
                                       DECL_ATTRIBUTES (t));
          if (at4 == NULL_TREE)
            {
              id = get_identifier ("omp declare target indirect");
              DECL_ATTRIBUTES (t)
                = tree_cons (id, NULL_TREE, DECL_ATTRIBUTES (t));
            }
        }
    }
  if ((device_type || indirect) && only_device_type_or_indirect)
    error_at (OMP_CLAUSE_LOCATION (clauses),
              "directive with only %<device_type%> or %<indirect%> clauses");
  if (indirect && device_type && device_type != OMP_CLAUSE_DEVICE_TYPE_ANY)
    error_at (OMP_CLAUSE_LOCATION (clauses),
              "%<device_type%> clause must specify 'any' when used with "
              "an %<indirect%> clause");
}

/* OpenMP 5.1
   #pragma omp begin assumes clauses[optseq] new-line

   #pragma omp begin declare target clauses[optseq] new-line  */

#define OMP_BEGIN_DECLARE_TARGET_CLAUSE_MASK                    \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEVICE_TYPE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_INDIRECT))

static void
c_parser_omp_begin (c_parser *parser)
{
  const char *p = "";
  c_parser_consume_pragma (parser);
  if (c_parser_next_token_is (parser, CPP_NAME))
    p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp (p, "declare") == 0)
    {
      c_parser_consume_token (parser);
      p = "";
      if (c_parser_next_token_is (parser, CPP_NAME))
        p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "target") == 0)
        {
          c_parser_consume_token (parser);
          bool attr_syntax = parser->in_omp_attribute_pragma != NULL;
          tree clauses
            = c_parser_omp_all_clauses (parser,
                                        OMP_BEGIN_DECLARE_TARGET_CLAUSE_MASK,
                                        "#pragma omp begin declare target");
          int device_type = 0;
          int indirect = 0;
          for (tree c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
            {
              if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_DEVICE_TYPE)
                device_type |= OMP_CLAUSE_DEVICE_TYPE_KIND (c);
              if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_INDIRECT)
                indirect |= !integer_zerop (OMP_CLAUSE_INDIRECT_EXPR (c));
            }
          c_omp_declare_target_attr attr = { attr_syntax, device_type,
                                             indirect };
          vec_safe_push (current_omp_declare_target_attribute, attr);
        }
      else
        {
          c_parser_error (parser, "expected %<target%>");
          c_parser_skip_to_pragma_eol (parser);
        }
    }
  else if (strcmp (p, "assumes") == 0)
    {
      c_parser_consume_token (parser);
      bool attr_syntax = parser->in_omp_attribute_pragma != NULL;
      c_parser_omp_assumption_clauses (parser, false);
      struct c_omp_begin_assumes_data a = { attr_syntax };
      vec_safe_push (current_omp_begin_assumes, a);
    }
  else
    {
      c_parser_error (parser, "expected %<declare target%> or %<assumes%>");
      c_parser_skip_to_pragma_eol (parser);
    }
}

/* OpenMP 4.0
   #pragma omp end declare target

   OpenMP 5.1
   #pragma omp end assumes  */

static void
c_parser_omp_end (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  const char *p = "";
  c_parser_consume_pragma (parser);
  if (c_parser_next_token_is (parser, CPP_NAME))
    p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
  if (strcmp (p, "declare") == 0)
    {
      c_parser_consume_token (parser);
      if (c_parser_next_token_is (parser, CPP_NAME)
          && strcmp (IDENTIFIER_POINTER (c_parser_peek_token (parser)->value),
                     "target") == 0)
        c_parser_consume_token (parser);
      else
        {
          c_parser_error (parser, "expected %<target%>");
          c_parser_skip_to_pragma_eol (parser);
          return;
        }
      bool attr_syntax = parser->in_omp_attribute_pragma != NULL;
      c_parser_skip_to_pragma_eol (parser);
      if (!vec_safe_length (current_omp_declare_target_attribute))
        error_at (loc, "%<#pragma omp end declare target%> without "
                       "corresponding %<#pragma omp declare target%> or "
                       "%<#pragma omp begin declare target%>");
      else
        {
          c_omp_declare_target_attr
            a = current_omp_declare_target_attribute->pop ();
          if (a.attr_syntax != attr_syntax)
            {
              if (a.attr_syntax)
                error_at (loc,
                          "%qs in attribute syntax terminated "
                          "with %qs in pragma syntax",
                          a.device_type >= 0 ? "begin declare target"
                                             : "declare target",
                          "end declare target");
              else
                error_at (loc,
                          "%qs in pragma syntax terminated "
                          "with %qs in attribute syntax",
                          a.device_type >= 0 ? "begin declare target"
                                             : "declare target",
                          "end declare target");
            }
        }
    }
  else if (strcmp (p, "assumes") == 0)
    {
      c_parser_consume_token (parser);
      bool attr_syntax = parser->in_omp_attribute_pragma != NULL;
      c_parser_skip_to_pragma_eol (parser);
      if (!vec_safe_length (current_omp_begin_assumes))
        error_at (loc, "%qs without corresponding %qs",
                  "#pragma omp end assumes", "#pragma omp begin assumes");
      else
        {
          c_omp_begin_assumes_data
            a = current_omp_begin_assumes->pop ();
          if (a.attr_syntax != attr_syntax)
            {
              if (a.attr_syntax)
                error_at (loc,
                          "%qs in attribute syntax terminated "
                          "with %qs in pragma syntax",
                          "begin assumes", "end assumes");
              else
                error_at (loc,
                          "%qs in pragma syntax terminated "
                          "with %qs in attribute syntax",
                          "begin assumes", "end assumes");
            }
        }
    }
  else
    {
      c_parser_error (parser, "expected %<declare%> or %<assumes%>");
      c_parser_skip_to_pragma_eol (parser);
    }
}

/* OpenMP 4.0
   #pragma omp declare reduction (reduction-id : typename-list : expression) \
      initializer-clause[opt] new-line

   initializer-clause:
      initializer (omp_priv = initializer)
      initializer (function-name (argument-list))  */

static void
c_parser_omp_declare_reduction (c_parser *parser, enum pragma_context context)
{
  unsigned int tokens_avail = 0, i;
  c_token *saved_tokens = NULL;
  vec<tree> types = vNULL;
  vec<c_token> clauses = vNULL;
  enum tree_code reduc_code = ERROR_MARK;
  tree reduc_id = NULL_TREE;
  tree type;
  location_t rloc = c_parser_peek_token (parser)->location;

  if (context == pragma_struct || context == pragma_param)
    {
      error ("%<#pragma omp declare reduction%> not at file or block scope");
      goto fail;
    }

  if (!c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
    goto fail;

  switch (c_parser_peek_token (parser)->type)
    {
    case CPP_PLUS:
      reduc_code = PLUS_EXPR;
      break;
    case CPP_MULT:
      reduc_code = MULT_EXPR;
      break;
    case CPP_MINUS:
      reduc_code = MINUS_EXPR;
      break;
    case CPP_AND:
      reduc_code = BIT_AND_EXPR;
      break;
    case CPP_XOR:
      reduc_code = BIT_XOR_EXPR;
      break;
    case CPP_OR:
      reduc_code = BIT_IOR_EXPR;
      break;
    case CPP_AND_AND:
      reduc_code = TRUTH_ANDIF_EXPR;
      break;
    case CPP_OR_OR:
      reduc_code = TRUTH_ORIF_EXPR;
      break;
    case CPP_NAME:
      const char *p;
      p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "min") == 0)
        {
          reduc_code = MIN_EXPR;
          break;
        }
      if (strcmp (p, "max") == 0)
        {
          reduc_code = MAX_EXPR;
          break;
        }
      reduc_id = c_parser_peek_token (parser)->value;
      break;
    default:
      c_parser_error (parser,
                      "expected %<+%>, %<*%>, %<-%>, %<&%>, "
                      "%<^%>, %<|%>, %<&&%>, %<||%> or identifier");
      goto fail;
    }

  tree orig_reduc_id, reduc_decl;
  orig_reduc_id = reduc_id;
  reduc_id = c_omp_reduction_id (reduc_code, reduc_id);
  reduc_decl = c_omp_reduction_decl (reduc_id);
  c_parser_consume_token (parser);

  if (!c_parser_require (parser, CPP_COLON, "expected %<:%>"))
    goto fail;

  while (true)
    {
      location_t loc = c_parser_peek_token (parser)->location;
      struct c_type_name *ctype = c_parser_type_name (parser);
      if (ctype != NULL)
        {
          type = groktypename (ctype, NULL, NULL);
          if (type == error_mark_node)
            ;
          else if ((INTEGRAL_TYPE_P (type)
                    || SCALAR_FLOAT_TYPE_P (type)
                    || TREE_CODE (type) == COMPLEX_TYPE)
                   && orig_reduc_id == NULL_TREE)
            error_at (loc, "predeclared arithmetic type in "
                           "%<#pragma omp declare reduction%>");
          else if (TREE_CODE (type) == FUNCTION_TYPE
                   || TREE_CODE (type) == ARRAY_TYPE)
            error_at (loc, "function or array type in "
                      "%<#pragma omp declare reduction%>");
          else if (TYPE_ATOMIC (type))
            error_at (loc, "%<_Atomic%> qualified type in "
                           "%<#pragma omp declare reduction%>");
          else if (TYPE_QUALS_NO_ADDR_SPACE (type))
            error_at (loc, "const, volatile or restrict qualified type in "
                           "%<#pragma omp declare reduction%>");
          else
            {
              tree t;
              for (t = DECL_INITIAL (reduc_decl); t; t = TREE_CHAIN (t))
                if (comptypes (TREE_PURPOSE (t), type))
                  {
                    error_at (loc, "redeclaration of %qs "
                                   "%<#pragma omp declare reduction%> for "
                                   "type %qT",
                                   IDENTIFIER_POINTER (reduc_id)
                                   + sizeof ("omp declare reduction ") - 1,
                                   type);
                    location_t ploc
                      = DECL_SOURCE_LOCATION (TREE_VEC_ELT (TREE_VALUE (t),
                                                            0));
                    error_at (ploc, "previous %<#pragma omp declare "
                                    "reduction%>");
                    break;
                  }
              if (t == NULL_TREE)
                types.safe_push (type);
            }
          if (c_parser_next_token_is (parser, CPP_COMMA))
            c_parser_consume_token (parser);
          else
            break;
        }
      else
        break;
    }

  if (!c_parser_require (parser, CPP_COLON, "expected %<:%>")
      || types.is_empty ())
    {
     fail:
      clauses.release ();
      types.release ();
      while (true)
        {
          c_token *token = c_parser_peek_token (parser);
          if (token->type == CPP_EOF || token->type == CPP_PRAGMA_EOL)
            break;
          c_parser_consume_token (parser);
        }
      c_parser_skip_to_pragma_eol (parser);
      return;
    }

  if (types.length () > 1)
    {
      while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
        {
          c_token *token = c_parser_peek_token (parser);
          if (token->type == CPP_EOF)
            goto fail;
          clauses.safe_push (*token);
          c_parser_consume_token (parser);
        }
      clauses.safe_push (*c_parser_peek_token (parser));
      c_parser_skip_to_pragma_eol (parser);

      /* Make sure nothing tries to read past the end of the tokens.  */
      c_token eof_token;
      memset (&eof_token, 0, sizeof (eof_token));
      eof_token.type = CPP_EOF;
      clauses.safe_push (eof_token);
      clauses.safe_push (eof_token);
    }

  int errs = errorcount;
  FOR_EACH_VEC_ELT (types, i, type)
    {
      saved_tokens = parser->tokens;
      tokens_avail = parser->tokens_avail;
      if (!clauses.is_empty ())
        {
          parser->tokens = clauses.address ();
          parser->tokens_avail = clauses.length ();
          parser->in_pragma = true;
        }

      bool nested = current_function_decl != NULL_TREE;
      if (nested)
        c_push_function_context ();
      tree fndecl = build_decl (BUILTINS_LOCATION, FUNCTION_DECL,
                                reduc_id, default_function_type);
      current_function_decl = fndecl;
      allocate_struct_function (fndecl, true);
      push_scope ();
      tree stmt = push_stmt_list ();
      /* Intentionally BUILTINS_LOCATION, so that -Wshadow doesn't
         warn about these.  */
      tree omp_out = build_decl (BUILTINS_LOCATION, VAR_DECL,
                                 get_identifier ("omp_out"), type);
      DECL_ARTIFICIAL (omp_out) = 1;
      DECL_CONTEXT (omp_out) = fndecl;
      pushdecl (omp_out);
      tree omp_in = build_decl (BUILTINS_LOCATION, VAR_DECL,
                                get_identifier ("omp_in"), type);
      DECL_ARTIFICIAL (omp_in) = 1;
      DECL_CONTEXT (omp_in) = fndecl;
      pushdecl (omp_in);
      struct c_expr combiner = c_parser_expression (parser);
      struct c_expr initializer;
      tree omp_priv = NULL_TREE, omp_orig = NULL_TREE;
      bool bad = false;
      initializer.set_error ();
      if (!c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
        bad = true;
      else if (c_parser_next_token_is (parser, CPP_COMMA)
               && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);
      if (!bad
          && (c_parser_next_token_is (parser, CPP_NAME)
              && strcmp (IDENTIFIER_POINTER
                                (c_parser_peek_token (parser)->value),
                          "initializer") == 0))
        {
          c_parser_consume_token (parser);
          pop_scope ();
          push_scope ();
          omp_priv = build_decl (BUILTINS_LOCATION, VAR_DECL,
                                 get_identifier ("omp_priv"), type);
          DECL_ARTIFICIAL (omp_priv) = 1;
          DECL_INITIAL (omp_priv) = error_mark_node;
          DECL_CONTEXT (omp_priv) = fndecl;
          pushdecl (omp_priv);
          omp_orig = build_decl (BUILTINS_LOCATION, VAR_DECL,
                                 get_identifier ("omp_orig"), type);
          DECL_ARTIFICIAL (omp_orig) = 1;
          DECL_CONTEXT (omp_orig) = fndecl;
          pushdecl (omp_orig);
          if (!c_parser_require (parser, CPP_OPEN_PAREN, "expected %<(%>"))
            bad = true;
          else if (!c_parser_next_token_is (parser, CPP_NAME))
            {
              c_parser_error (parser, "expected %<omp_priv%> or "
                                      "function-name");
              bad = true;
            }
          else if (strcmp (IDENTIFIER_POINTER
                                (c_parser_peek_token (parser)->value),
                           "omp_priv") != 0)
            {
              if (c_parser_peek_2nd_token (parser)->type != CPP_OPEN_PAREN
                  || c_parser_peek_token (parser)->id_kind != C_ID_ID)
                {
                  c_parser_error (parser, "expected function-name %<(%>");
                  bad = true;
                }
              else
                initializer = c_parser_postfix_expression (parser);
              if (initializer.value
                  && TREE_CODE (initializer.value) == CALL_EXPR)
                {
                  int j;
                  tree c = initializer.value;
                  for (j = 0; j < call_expr_nargs (c); j++)
                    {
                      tree a = CALL_EXPR_ARG (c, j);
                      STRIP_NOPS (a);
                      if (TREE_CODE (a) == ADDR_EXPR
                          && TREE_OPERAND (a, 0) == omp_priv)
                        break;
                    }
                  if (j == call_expr_nargs (c))
                    error ("one of the initializer call arguments should be "
                           "%<&omp_priv%>");
                }
            }
          else
            {
              c_parser_consume_token (parser);
              if (!c_parser_require (parser, CPP_EQ, "expected %<=%>"))
                bad = true;
              else
                {
                  tree st = push_stmt_list ();
                  location_t loc = c_parser_peek_token (parser)->location;
                  rich_location richloc (line_table, loc);
                  start_init (omp_priv, NULL_TREE, false, false, &richloc);
                  struct c_expr init = c_parser_initializer (parser, omp_priv);
                  finish_init ();
                  finish_decl (omp_priv, loc, init.value,
                               init.original_type, NULL_TREE);
                  pop_stmt_list (st);
                }
            }
          if (!bad
              && !c_parser_require (parser, CPP_CLOSE_PAREN, "expected %<)%>"))
            bad = true;
        }

      if (!bad)
        {
          c_parser_skip_to_pragma_eol (parser);

          tree t = tree_cons (type, make_tree_vec (omp_priv ? 6 : 3),
                              DECL_INITIAL (reduc_decl));
          DECL_INITIAL (reduc_decl) = t;
          DECL_SOURCE_LOCATION (omp_out) = rloc;
          TREE_VEC_ELT (TREE_VALUE (t), 0) = omp_out;
          TREE_VEC_ELT (TREE_VALUE (t), 1) = omp_in;
          TREE_VEC_ELT (TREE_VALUE (t), 2) = combiner.value;
          walk_tree (&combiner.value, c_check_omp_declare_reduction_r,
                     &TREE_VEC_ELT (TREE_VALUE (t), 0), NULL);
          if (omp_priv)
            {
              DECL_SOURCE_LOCATION (omp_priv) = rloc;
              TREE_VEC_ELT (TREE_VALUE (t), 3) = omp_priv;
              TREE_VEC_ELT (TREE_VALUE (t), 4) = omp_orig;
              TREE_VEC_ELT (TREE_VALUE (t), 5) = initializer.value;
              walk_tree (&initializer.value, c_check_omp_declare_reduction_r,
                         &TREE_VEC_ELT (TREE_VALUE (t), 3), NULL);
              walk_tree (&DECL_INITIAL (omp_priv),
                         c_check_omp_declare_reduction_r,
                         &TREE_VEC_ELT (TREE_VALUE (t), 3), NULL);
            }
        }

      pop_stmt_list (stmt);
      pop_scope ();
      if (cfun->language != NULL)
        {
          ggc_free (cfun->language);
          cfun->language = NULL;
        }
      set_cfun (NULL);
      current_function_decl = NULL_TREE;
      if (nested)
        c_pop_function_context ();

      if (!clauses.is_empty ())
        {
          parser->tokens = saved_tokens;
          parser->tokens_avail = tokens_avail;
        }
      if (bad)
        goto fail;
      if (errs != errorcount)
        break;
    }

  clauses.release ();
  types.release ();
}


/* OpenMP 4.0
   #pragma omp declare simd declare-simd-clauses[optseq] new-line
   #pragma omp declare reduction (reduction-id : typename-list : expression) \
      initializer-clause[opt] new-line
   #pragma omp declare target new-line

   OpenMP 5.0
   #pragma omp declare variant (identifier) match (context-selector)  */

static bool
c_parser_omp_declare (c_parser *parser, enum pragma_context context)
{
  c_parser_consume_pragma (parser);
  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      if (strcmp (p, "simd") == 0)
        {
          /* c_parser_consume_token (parser); done in
             c_parser_omp_declare_simd.  */
          c_parser_omp_declare_simd (parser, context);
          return true;
        }
      if (strcmp (p, "reduction") == 0)
        {
          c_parser_consume_token (parser);
          c_parser_omp_declare_reduction (parser, context);
          return false;
        }
      if (!flag_openmp)  /* flag_openmp_simd  */
        {
          c_parser_skip_to_pragma_eol (parser, false);
          return false;
        }
      if (strcmp (p, "target") == 0)
        {
          c_parser_consume_token (parser);
          c_parser_omp_declare_target (parser);
          return false;
        }
      if (strcmp (p, "variant") == 0)
        {
          /* c_parser_consume_token (parser); done in
             c_parser_omp_declare_simd.  */
          c_parser_omp_declare_simd (parser, context);
          return true;
        }
    }

  c_parser_error (parser, "expected %<simd%>, %<reduction%>, "
                          "%<target%> or %<variant%>");
  c_parser_skip_to_pragma_eol (parser);
  return false;
}

/* OpenMP 5.0
   #pragma omp requires clauses[optseq] new-line  */

static void
c_parser_omp_requires (c_parser *parser)
{
  enum omp_requires new_req = (enum omp_requires) 0;

  c_parser_consume_pragma (parser);

  location_t loc = c_parser_peek_token (parser)->location;
  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);

      if (c_parser_next_token_is (parser, CPP_NAME))
        {
          const char *p
            = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
          location_t cloc = c_parser_peek_token (parser)->location;
          enum omp_requires this_req = (enum omp_requires) 0;

          if (!strcmp (p, "unified_address"))
            this_req = OMP_REQUIRES_UNIFIED_ADDRESS;
          else if (!strcmp (p, "unified_shared_memory"))
            this_req = OMP_REQUIRES_UNIFIED_SHARED_MEMORY;
          else if (!strcmp (p, "dynamic_allocators"))
            this_req = OMP_REQUIRES_DYNAMIC_ALLOCATORS;
          else if (!strcmp (p, "reverse_offload"))
            this_req = OMP_REQUIRES_REVERSE_OFFLOAD;
          else if (!strcmp (p, "atomic_default_mem_order"))
            {
              c_parser_consume_token (parser);

              matching_parens parens;
              if (parens.require_open (parser))
                {
                  if (c_parser_next_token_is (parser, CPP_NAME))
                    {
                      tree v = c_parser_peek_token (parser)->value;
                      p = IDENTIFIER_POINTER (v);

                      if (!strcmp (p, "seq_cst"))
                        this_req
                          = (enum omp_requires) OMP_MEMORY_ORDER_SEQ_CST;
                      else if (!strcmp (p, "relaxed"))
                        this_req
                          = (enum omp_requires) OMP_MEMORY_ORDER_RELAXED;
                      else if (!strcmp (p, "release"))
                        this_req
                          = (enum omp_requires) OMP_MEMORY_ORDER_RELEASE;
                      else if (!strcmp (p, "acq_rel"))
                        this_req
                          = (enum omp_requires) OMP_MEMORY_ORDER_ACQ_REL;
                      else if (!strcmp (p, "acquire"))
                        this_req
                          = (enum omp_requires) OMP_MEMORY_ORDER_ACQUIRE;
                    }
                  if (this_req == 0)
                    {
                      error_at (c_parser_peek_token (parser)->location,
                                "expected %<acq_rel%>, %<acquire%>, "
                                "%<relaxed%>, %<release%> or %<seq_cst%>");
                      switch (c_parser_peek_token (parser)->type)
                        {
                        case CPP_EOF:
                        case CPP_PRAGMA_EOL:
                        case CPP_CLOSE_PAREN:
                          break;
                        default:
                          if (c_parser_peek_2nd_token (parser)->type
                              == CPP_CLOSE_PAREN)
                            c_parser_consume_token (parser);
                          break;
                        }
                    }
                  else
                    c_parser_consume_token (parser);

                  parens.skip_until_found_close (parser);
                  if (this_req == 0)
                    {
                      c_parser_skip_to_pragma_eol (parser, false);
                      return;
                    }
                }
              p = NULL;
            }
          else
            {
              error_at (cloc, "expected %<unified_address%>, "
                              "%<unified_shared_memory%>, "
                              "%<dynamic_allocators%>, "
                               "%<reverse_offload%> "
                               "or %<atomic_default_mem_order%> clause");
              c_parser_skip_to_pragma_eol (parser, false);
              return;
            }
          if (p)
            c_parser_consume_token (parser);
          if (this_req)
            {
              if ((this_req & ~OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER) != 0)
                {
                  if ((this_req & new_req) != 0)
                    error_at (cloc, "too many %qs clauses", p);
                  if (this_req != OMP_REQUIRES_DYNAMIC_ALLOCATORS
                      && (omp_requires_mask & OMP_REQUIRES_TARGET_USED) != 0)
                    error_at (cloc, "%qs clause used lexically after first "
                                    "target construct or offloading API", p);
                }
              else if ((new_req & OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER) != 0)
                {
                  error_at (cloc, "too many %qs clauses",
                            "atomic_default_mem_order");
                  this_req = (enum omp_requires) 0;
                }
              else if ((omp_requires_mask
                        & OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER) != 0)
                {
                  error_at (cloc, "more than one %<atomic_default_mem_order%>"
                                  " clause in a single compilation unit");
                  this_req
                    = (enum omp_requires)
                       (omp_requires_mask
                        & OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER);
                }
              else if ((omp_requires_mask
                        & OMP_REQUIRES_ATOMIC_DEFAULT_MEM_ORDER_USED) != 0)
                error_at (cloc, "%<atomic_default_mem_order%> clause used "
                                "lexically after first %<atomic%> construct "
                                "without memory order clause");
              new_req = (enum omp_requires) (new_req | this_req);
              omp_requires_mask
                = (enum omp_requires) (omp_requires_mask | this_req);
              continue;
            }
        }
      break;
    }
  c_parser_skip_to_pragma_eol (parser);

  if (new_req == 0)
    error_at (loc, "%<pragma omp requires%> requires at least one clause");
}

/* Helper function for c_parser_omp_taskloop.
   Disallow zero sized or potentially zero sized task reductions.  */

static tree
c_finish_taskloop_clauses (tree clauses)
{
  tree *pc = &clauses;
  for (tree c = clauses; c; c = *pc)
    {
      bool remove = false;
      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION)
        {
          tree type = strip_array_types (TREE_TYPE (OMP_CLAUSE_DECL (c)));
          if (integer_zerop (TYPE_SIZE_UNIT (type)))
            {
              error_at (OMP_CLAUSE_LOCATION (c),
                        "zero sized type %qT in %<reduction%> clause", type);
              remove = true;
            }
          else if (TREE_CODE (TYPE_SIZE_UNIT (type)) != INTEGER_CST)
            {
              error_at (OMP_CLAUSE_LOCATION (c),
                        "variable sized type %qT in %<reduction%> clause",
                        type);
              remove = true;
            }
        }
      if (remove)
        *pc = OMP_CLAUSE_CHAIN (c);
      else
        pc = &OMP_CLAUSE_CHAIN (c);
    }
  return clauses;
}

/* OpenMP 4.5:
   #pragma omp taskloop taskloop-clause[optseq] new-line
     for-loop

   #pragma omp taskloop simd taskloop-simd-clause[optseq] new-line
     for-loop  */

#define OMP_TASKLOOP_CLAUSE_MASK                                \
        ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_SHARED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIVATE)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FIRSTPRIVATE) \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_LASTPRIVATE)  \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_DEFAULT)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_GRAINSIZE)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NUM_TASKS)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_UNTIED)       \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IF)           \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_FINAL)        \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_MERGEABLE)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NOGROUP)      \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRIORITY)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_ALLOCATE)     \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)    \
        | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IN_REDUCTION))

static tree
c_parser_omp_taskloop (location_t loc, c_parser *parser,
                       char *p_name, omp_clause_mask mask, tree *cclauses,
                       bool *if_p)
{
  tree clauses, block, ret;

  strcat (p_name, " taskloop");
  mask |= OMP_TASKLOOP_CLAUSE_MASK;
  /* #pragma omp parallel master taskloop{, simd} disallow in_reduction
     clause.  */
  if ((mask & (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NUM_THREADS)) != 0)
    mask &= ~(OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_IN_REDUCTION);

  if (c_parser_next_token_is (parser, CPP_NAME))
    {
      const char *p = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);

      if (strcmp (p, "simd") == 0)
        {
          tree cclauses_buf[C_OMP_CLAUSE_SPLIT_COUNT];
          if (cclauses == NULL)
            cclauses = cclauses_buf;
          c_parser_consume_token (parser);
          if (!flag_openmp)  /* flag_openmp_simd  */
            return c_parser_omp_simd (loc, parser, p_name, mask, cclauses,
                                      if_p);
          block = c_begin_compound_stmt (true);
          ret = c_parser_omp_simd (loc, parser, p_name, mask, cclauses, if_p);
          block = c_end_compound_stmt (loc, block, true);
          if (ret == NULL)
            return ret;
          ret = make_node (OMP_TASKLOOP);
          TREE_TYPE (ret) = void_type_node;
          OMP_FOR_BODY (ret) = block;
          OMP_FOR_CLAUSES (ret) = cclauses[C_OMP_CLAUSE_SPLIT_TASKLOOP];
          OMP_FOR_CLAUSES (ret)
            = c_finish_taskloop_clauses (OMP_FOR_CLAUSES (ret));
          SET_EXPR_LOCATION (ret, loc);
          add_stmt (ret);
          return ret;
        }
    }
  if (!flag_openmp)  /* flag_openmp_simd  */
    {
      c_parser_skip_to_pragma_eol (parser, false);
      return NULL_TREE;
    }

  clauses = c_parser_omp_all_clauses (parser, mask, p_name, cclauses == NULL);
  if (cclauses)
    {
      omp_split_clauses (loc, OMP_TASKLOOP, mask, clauses, cclauses);
      clauses = cclauses[C_OMP_CLAUSE_SPLIT_TASKLOOP];
    }

  clauses = c_finish_taskloop_clauses (clauses);
  block = c_begin_compound_stmt (true);
  ret = c_parser_omp_for_loop (loc, parser, OMP_TASKLOOP, clauses, NULL, if_p);
  block = c_end_compound_stmt (loc, block, true);
  add_stmt (block);

  return ret;
}

/* OpenMP 5.1
   #pragma omp nothing new-line  */

static void
c_parser_omp_nothing (c_parser *parser)
{
  c_parser_consume_pragma (parser);
  c_parser_skip_to_pragma_eol (parser);
}

/* OpenMP 5.1
   #pragma omp error clauses[optseq] new-line  */

static bool
c_parser_omp_error (c_parser *parser, enum pragma_context context)
{
  int at_compilation = -1;
  int severity_fatal = -1;
  tree message = NULL_TREE;
  bool bad = false;
  location_t loc = c_parser_peek_token (parser)->location;

  c_parser_consume_pragma (parser);

  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);

      if (!c_parser_next_token_is (parser, CPP_NAME))
        break;

      const char *p
        = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      location_t cloc = c_parser_peek_token (parser)->location;
      static const char *args[] = {
        "execution", "compilation", "warning", "fatal"
      };
      int *v = NULL;
      int idx = 0, n = -1;
      tree m = NULL_TREE;

      if (!strcmp (p, "at"))
        v = &at_compilation;
      else if (!strcmp (p, "severity"))
        {
          v = &severity_fatal;
          idx += 2;
        }
      else if (strcmp (p, "message"))
        {
          error_at (cloc,
                    "expected %<at%>, %<severity%> or %<message%> clause");
          c_parser_skip_to_pragma_eol (parser, false);
          return false;
        }

      c_parser_consume_token (parser);

      matching_parens parens;
      if (parens.require_open (parser))
        {
          if (v == NULL)
            {
              location_t expr_loc = c_parser_peek_token (parser)->location;
              c_expr expr = c_parser_expr_no_commas (parser, NULL);
              expr = convert_lvalue_to_rvalue (expr_loc, expr, true, true);
              m = convert (const_string_type_node, expr.value);
              m = c_fully_fold (m, false, NULL);
            }
          else
            {
              if (c_parser_next_token_is (parser, CPP_NAME))
                {
                  tree val = c_parser_peek_token (parser)->value;
                  const char *q = IDENTIFIER_POINTER (val);

                  if (!strcmp (q, args[idx]))
                    n = 0;
                  else if (!strcmp (q, args[idx + 1]))
                    n = 1;
                }
              if (n == -1)
                {
                  error_at (c_parser_peek_token (parser)->location,
                            "expected %qs or %qs", args[idx], args[idx + 1]);
                  bad = true;
                  switch (c_parser_peek_token (parser)->type)
                    {
                    case CPP_EOF:
                    case CPP_PRAGMA_EOL:
                    case CPP_CLOSE_PAREN:
                      break;
                    default:
                      if (c_parser_peek_2nd_token (parser)->type
                          == CPP_CLOSE_PAREN)
                        c_parser_consume_token (parser);
                      break;
                    }
                }
              else
                c_parser_consume_token (parser);
            }

          parens.skip_until_found_close (parser);

          if (v == NULL)
            {
              if (message)
                {
                  error_at (cloc, "too many %qs clauses", p);
                  bad = true;
                }
              else
                message = m;
            }
          else if (n != -1)
            {
              if (*v != -1)
                {
                  error_at (cloc, "too many %qs clauses", p);
                  bad = true;
                }
              else
                *v = n;
            }
        }
      else
        bad = true;
    }
  c_parser_skip_to_pragma_eol (parser);
  if (bad)
    return true;

  if (at_compilation == -1)
    at_compilation = 1;
  if (severity_fatal == -1)
    severity_fatal = 1;
  if (!at_compilation)
    {
      if (context != pragma_compound)
        {
          error_at (loc, "%<#pragma omp error%> with %<at(execution)%> clause "
                         "may only be used in compound statements");
          return true;
        }
      tree fndecl
        = builtin_decl_explicit (severity_fatal ? BUILT_IN_GOMP_ERROR
                                                : BUILT_IN_GOMP_WARNING);
      if (!message)
        message = build_zero_cst (const_string_type_node);
      tree stmt = build_call_expr_loc (loc, fndecl, 2, message,
                                       build_all_ones_cst (size_type_node));
      add_stmt (stmt);
      return true;
    }
  const char *msg = NULL;
  if (message)
    {
      msg = c_getstr (message);
      if (msg == NULL)
        msg = _("<message unknown at compile time>");
    }
  if (msg)
    emit_diagnostic (severity_fatal ? DK_ERROR : DK_WARNING, loc, 0,
                     "%<pragma omp error%> encountered: %s", msg);
  else
    emit_diagnostic (severity_fatal ? DK_ERROR : DK_WARNING, loc, 0,
                     "%<pragma omp error%> encountered");
  return false;
}

/* Assumption clauses:
   OpenMP 5.1
   absent (directive-name-list)
   contains (directive-name-list)
   holds (expression)
   no_openmp
   no_openmp_routines
   no_parallelism  */

static void
c_parser_omp_assumption_clauses (c_parser *parser, bool is_assume)
{
  bool no_openmp = false;
  bool no_openmp_routines = false;
  bool no_parallelism = false;
  bitmap_head absent_head, contains_head;

  bitmap_obstack_initialize (NULL);
  bitmap_initialize (&absent_head, &bitmap_default_obstack);
  bitmap_initialize (&contains_head, &bitmap_default_obstack);

  if (c_parser_next_token_is (parser, CPP_PRAGMA_EOL))
    error_at (c_parser_peek_token (parser)->location,
              "expected at least one assumption clause");

  while (c_parser_next_token_is_not (parser, CPP_PRAGMA_EOL))
    {
      if (c_parser_next_token_is (parser, CPP_COMMA)
          && c_parser_peek_2nd_token (parser)->type == CPP_NAME)
        c_parser_consume_token (parser);

      if (!c_parser_next_token_is (parser, CPP_NAME))
        break;

      const char *p
        = IDENTIFIER_POINTER (c_parser_peek_token (parser)->value);
      location_t cloc = c_parser_peek_token (parser)->location;

      if (!strcmp (p, "no_openmp"))
        {
          c_parser_consume_token (parser);
          if (no_openmp)
            error_at (cloc, "too many %qs clauses", "no_openmp");
          no_openmp = true;
        }
      else if (!strcmp (p, "no_openmp_routines"))
        {
          c_parser_consume_token (parser);
          if (no_openmp_routines)
            error_at (cloc, "too many %qs clauses", "no_openmp_routines");
          no_openmp_routines = true;
        }
      else if (!strcmp (p, "no_parallelism"))
        {
          c_parser_consume_token (parser);
          if (no_parallelism)
            error_at (cloc, "too many %qs clauses", "no_parallelism");
          no_parallelism = true;
        }
      else if (!strcmp (p, "holds"))
        {
          c_parser_consume_token (parser);
          matching_parens parens;
          if (parens.require_open (parser))
            {
              location_t eloc = c_parser_peek_token (parser)->location;
              c_expr expr = c_parser_expr_no_commas (parser, NULL);
              tree t = convert_lvalue_to_rvalue (eloc, expr, true, true).value;
              t = c_objc_common_truthvalue_conversion (eloc, t);
              t = c_fully_fold (t, false, NULL);
              if (is_assume && t != error_mark_node)
                {
                  tree fn = build_call_expr_internal_loc (eloc, IFN_ASSUME,
                                                          void_type_node, 1,
                                                          t);
                  add_stmt (fn);
                }
              parens.skip_until_found_close (parser);
            }
        }
      else if (!strcmp (p, "absent") || !strcmp (p, "contains"))
        {
          c_parser_consume_token (parser);
          matching_parens parens;
          if (parens.require_open (parser))
            {
              do
                {
                  const char *directive[3] = {};
                  int i;
                  location_t dloc = c_parser_peek_token (parser)->location;
                  for (i = 0; i < 3; i++)
                    {
                      tree id;
                      if (c_parser_peek_nth_token (parser, i + 1)->type
                          == CPP_NAME)
                        id = c_parser_peek_nth_token (parser, i + 1)->value;
                      else if (c_parser_peek_nth_token (parser, i + 1)->keyword
                               != RID_MAX)
                        {
                          enum rid rid
                            = c_parser_peek_nth_token (parser, i + 1)->keyword;
                          id = ridpointers[rid];
                        }
                      else
                        break;
                      directive[i] = IDENTIFIER_POINTER (id);
                    }
                  if (i == 0)
                    error_at (dloc, "expected directive name");
                  else
                    {
                      const struct c_omp_directive *dir
                        = c_omp_categorize_directive (directive[0],
                                                      directive[1],
                                                      directive[2]);
                      if (dir == NULL
                          || dir->kind == C_OMP_DIR_DECLARATIVE
                          || dir->kind == C_OMP_DIR_INFORMATIONAL
                          || dir->id == PRAGMA_OMP_END
                          || (!dir->second && directive[1])
                          || (!dir->third && directive[2]))
                        error_at (dloc, "unknown OpenMP directive name in "
                                        "%qs clause argument", p);
                      else
                        {
                          int id = dir - c_omp_directives;
                          if (bitmap_bit_p (p[0] == 'a' ? &contains_head
                                                        : &absent_head, id))
                            error_at (dloc, "%<%s%s%s%s%s%> directive "
                                            "mentioned in both %<absent%> and "
                                            "%<contains%> clauses",
                                      directive[0],
                                      directive[1] ? " " : "",
                                      directive[1] ? directive[1] : "",
                                      directive[2] ? " " : "",
                                      directive[2] ? directive[2] : "");
                          else if (!bitmap_set_bit (p[0] == 'a'
                                                    ? &absent_head
                                                    : &contains_head, id))
                            error_at (dloc, "%<%s%s%s%s%s%> directive "
                                            "mentioned multiple times in %qs "
                                            "clauses",
                                      directive[0],
                                      directive[1] ? " " : "",
                                      directive[1] ? directive[1] : "",
                                      directive[2] ? " " : "",
                                      directive[2] ? directive[2] : "", p);
                        }
                      for (; i; --i)
                        c_parser_consume_token (parser);
                    }
                  if (c_parser_next_token_is (parser, CPP_COMMA))
                    c_parser_consume_token (parser);
                  else
                    break;
                }
              while (1);
              parens.skip_until_found_close (parser);
            }
        }
      else if (startswith (p, "ext_"))
        {
          warning_at (cloc, OPT_Wopenmp, "unknown assumption clause %qs", p);
          c_parser_consume_token (parser);
          if (c_parser_next_token_is (parser, CPP_OPEN_PAREN))
            {
              matching_parens parens;
              parens.consume_open (parser);
              c_parser_balanced_token_sequence (parser);
              parens.require_close (parser);
            }
        }
      else
        {
          c_parser_consume_token (parser);
          error_at (cloc, "expected assumption clause");
          break;
        }
    }
  c_parser_skip_to_pragma_eol (parser);
}

/* OpenMP 5.1
   #pragma omp assume clauses[optseq] new-line  */

static void
c_parser_omp_assume (c_parser *parser, bool *if_p)
{
  c_parser_omp_assumption_clauses (parser, true);
  add_stmt (c_parser_omp_structured_block (parser, if_p));
}

/* OpenMP 5.1
   #pragma omp assumes clauses[optseq] new-line  */

static void
c_parser_omp_assumes (c_parser *parser)
{
  c_parser_consume_pragma (parser);
  c_parser_omp_assumption_clauses (parser, false);
}

/* Main entry point to parsing most OpenMP pragmas.  */

static void
c_parser_omp_construct (c_parser *parser, bool *if_p)
{
  enum pragma_kind p_kind;
  location_t loc;
  tree stmt;
  char p_name[sizeof "#pragma omp teams distribute parallel for simd"];
  omp_clause_mask mask (0);

  loc = c_parser_peek_token (parser)->location;
  p_kind = c_parser_peek_token (parser)->pragma_kind;
  c_parser_consume_pragma (parser);

  switch (p_kind)
    {
    case PRAGMA_OACC_ATOMIC:
      c_parser_omp_atomic (loc, parser, true);
      return;
    case PRAGMA_OACC_CACHE:
      strcpy (p_name, "#pragma acc");
      stmt = c_parser_oacc_cache (loc, parser);
      break;
    case PRAGMA_OACC_DATA:
      stmt = c_parser_oacc_data (loc, parser, if_p);
      break;
    case PRAGMA_OACC_HOST_DATA:
      stmt = c_parser_oacc_host_data (loc, parser, if_p);
      break;
    case PRAGMA_OACC_KERNELS:
    case PRAGMA_OACC_PARALLEL:
    case PRAGMA_OACC_SERIAL:
      strcpy (p_name, "#pragma acc");
      stmt = c_parser_oacc_compute (loc, parser, p_kind, p_name, if_p);
      break;
    case PRAGMA_OACC_LOOP:
      strcpy (p_name, "#pragma acc");
      stmt = c_parser_oacc_loop (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OACC_WAIT:
      strcpy (p_name, "#pragma wait");
      stmt = c_parser_oacc_wait (loc, parser, p_name);
      break;
    case PRAGMA_OMP_ATOMIC:
      c_parser_omp_atomic (loc, parser, false);
      return;
    case PRAGMA_OMP_CRITICAL:
      stmt = c_parser_omp_critical (loc, parser, if_p);
      break;
    case PRAGMA_OMP_DISTRIBUTE:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_distribute (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_FOR:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_for (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_LOOP:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_loop (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_MASKED:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_masked (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_MASTER:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_master (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_PARALLEL:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_parallel (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_SCOPE:
      stmt = c_parser_omp_scope (loc, parser, if_p);
      break;
    case PRAGMA_OMP_SECTIONS:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_sections (loc, parser, p_name, mask, NULL);
      break;
    case PRAGMA_OMP_SIMD:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_simd (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_SINGLE:
      stmt = c_parser_omp_single (loc, parser, if_p);
      break;
    case PRAGMA_OMP_TASK:
      stmt = c_parser_omp_task (loc, parser, if_p);
      break;
    case PRAGMA_OMP_TASKGROUP:
      stmt = c_parser_omp_taskgroup (loc, parser, if_p);
      break;
    case PRAGMA_OMP_TASKLOOP:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_taskloop (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_TEAMS:
      strcpy (p_name, "#pragma omp");
      stmt = c_parser_omp_teams (loc, parser, p_name, mask, NULL, if_p);
      break;
    case PRAGMA_OMP_ASSUME:
      c_parser_omp_assume (parser, if_p);
      return;
    default:
      gcc_unreachable ();
    }

  if (stmt && stmt != error_mark_node)
    gcc_assert (EXPR_LOCATION (stmt) != UNKNOWN_LOCATION);
}


/* OpenMP 2.5:
   # pragma omp threadprivate (variable-list) */

static void
c_parser_omp_threadprivate (c_parser *parser)
{
  tree vars, t;
  location_t loc;

  c_parser_consume_pragma (parser);
  loc = c_parser_peek_token (parser)->location;
  vars = c_parser_omp_var_list_parens (parser, OMP_CLAUSE_ERROR, NULL);

  /* Mark every variable in VARS to be assigned thread local storage.  */
  for (t = vars; t; t = TREE_CHAIN (t))
    {
      tree v = TREE_PURPOSE (t);

      /* FIXME diagnostics: Ideally we should keep individual
         locations for all the variables in the var list to make the
         following errors more precise.  Perhaps
         c_parser_omp_var_list_parens() should construct a list of
         locations to go along with the var list.  */

      /* If V had already been marked threadprivate, it doesn't matter
         whether it had been used prior to this point.  */
      if (!VAR_P (v))
        error_at (loc, "%qD is not a variable", v);
      else if (TREE_USED (v) && !C_DECL_THREADPRIVATE_P (v))
        error_at (loc, "%qE declared %<threadprivate%> after first use", v);
      else if (! is_global_var (v))
        error_at (loc, "automatic variable %qE cannot be %<threadprivate%>", v);
      else if (TREE_TYPE (v) == error_mark_node)
        ;
      else if (! COMPLETE_TYPE_P (TREE_TYPE (v)))
        error_at (loc, "%<threadprivate%> %qE has incomplete type", v);
      else
        {
          if (! DECL_THREAD_LOCAL_P (v))
            {
              set_decl_tls_model (v, decl_default_tls_model (v));
              /* If rtl has been already set for this var, call
                 make_decl_rtl once again, so that encode_section_info
                 has a chance to look at the new decl flags.  */
              if (DECL_RTL_SET_P (v))
                make_decl_rtl (v);
            }
          C_DECL_THREADPRIVATE_P (v) = 1;
        }
    }

  c_parser_skip_to_pragma_eol (parser);
}

/* Parse a transaction attribute (GCC Extension).

   transaction-attribute:
     gnu-attributes
     attribute-specifier
*/

static tree
c_parser_transaction_attributes (c_parser *parser)
{
  if (c_parser_next_token_is_keyword (parser, RID_ATTRIBUTE))
    return c_parser_gnu_attributes (parser);

  if (!c_parser_next_token_is (parser, CPP_OPEN_SQUARE))
    return NULL_TREE;
  return c_parser_std_attribute_specifier (parser, true);
}

/* Parse a __transaction_atomic or __transaction_relaxed statement
   (GCC Extension).

   transaction-statement:
     __transaction_atomic transaction-attribute[opt] compound-statement
     __transaction_relaxed compound-statement

   Note that the only valid attribute is: "outer".
*/

static tree
c_parser_transaction (c_parser *parser, enum rid keyword)
{
  unsigned int old_in = parser->in_transaction;
  unsigned int this_in = 1, new_in;
  location_t loc = c_parser_peek_token (parser)->location;
  tree stmt, attrs;

  gcc_assert ((keyword == RID_TRANSACTION_ATOMIC
      || keyword == RID_TRANSACTION_RELAXED)
      && c_parser_next_token_is_keyword (parser, keyword));
  c_parser_consume_token (parser);

  if (keyword == RID_TRANSACTION_RELAXED)
    this_in |= TM_STMT_ATTR_RELAXED;
  else
    {
      attrs = c_parser_transaction_attributes (parser);
      if (attrs)
        this_in |= parse_tm_stmt_attr (attrs, TM_STMT_ATTR_OUTER);
    }

  /* Keep track if we're in the lexical scope of an outer transaction.  */
  new_in = this_in | (old_in & TM_STMT_ATTR_OUTER);

  parser->in_transaction = new_in;
  stmt = c_parser_compound_statement (parser);
  parser->in_transaction = old_in;

  if (flag_tm)
    stmt = c_finish_transaction (loc, stmt, this_in);
  else
    error_at (loc, (keyword == RID_TRANSACTION_ATOMIC ?
        "%<__transaction_atomic%> without transactional memory support enabled"
        : "%<__transaction_relaxed %> "
        "without transactional memory support enabled"));

  return stmt;
}

/* Parse a __transaction_atomic or __transaction_relaxed expression
   (GCC Extension).

   transaction-expression:
     __transaction_atomic ( expression )
     __transaction_relaxed ( expression )
*/

static struct c_expr
c_parser_transaction_expression (c_parser *parser, enum rid keyword)
{
  struct c_expr ret;
  unsigned int old_in = parser->in_transaction;
  unsigned int this_in = 1;
  location_t loc = c_parser_peek_token (parser)->location;
  tree attrs;

  gcc_assert ((keyword == RID_TRANSACTION_ATOMIC
      || keyword == RID_TRANSACTION_RELAXED)
      && c_parser_next_token_is_keyword (parser, keyword));
  c_parser_consume_token (parser);

  if (keyword == RID_TRANSACTION_RELAXED)
    this_in |= TM_STMT_ATTR_RELAXED;
  else
    {
      attrs = c_parser_transaction_attributes (parser);
      if (attrs)
        this_in |= parse_tm_stmt_attr (attrs, 0);
    }

  parser->in_transaction = this_in;
  matching_parens parens;
  if (parens.require_open (parser))
    {
      tree expr = c_parser_expression (parser).value;
      ret.original_type = TREE_TYPE (expr);
      ret.value = build1 (TRANSACTION_EXPR, ret.original_type, expr);
      if (this_in & TM_STMT_ATTR_RELAXED)
        TRANSACTION_EXPR_RELAXED (ret.value) = 1;
      SET_EXPR_LOCATION (ret.value, loc);
      ret.original_code = TRANSACTION_EXPR;
      ret.m_decimal = 0;
      if (!parens.require_close (parser))
        {
          c_parser_skip_until_found (parser, CPP_CLOSE_PAREN, NULL);
          goto error;
        }
    }
  else
    {
     error:
      ret.set_error ();
      ret.original_code = ERROR_MARK;
      ret.original_type = NULL;
    }
  parser->in_transaction = old_in;

  if (!flag_tm)
    error_at (loc, (keyword == RID_TRANSACTION_ATOMIC ?
        "%<__transaction_atomic%> without transactional memory support enabled"
        : "%<__transaction_relaxed %> "
        "without transactional memory support enabled"));

  set_c_expr_source_range (&ret, loc, loc);

  return ret;
}

/* Parse a __transaction_cancel statement (GCC Extension).

   transaction-cancel-statement:
     __transaction_cancel transaction-attribute[opt] ;

   Note that the only valid attribute is "outer".
*/

static tree
c_parser_transaction_cancel (c_parser *parser)
{
  location_t loc = c_parser_peek_token (parser)->location;
  tree attrs;
  bool is_outer = false;

  gcc_assert (c_parser_next_token_is_keyword (parser, RID_TRANSACTION_CANCEL));
  c_parser_consume_token (parser);

  attrs = c_parser_transaction_attributes (parser);
  if (attrs)
    is_outer = (parse_tm_stmt_attr (attrs, TM_STMT_ATTR_OUTER) != 0);

  if (!flag_tm)
    {
      error_at (loc, "%<__transaction_cancel%> without "
                "transactional memory support enabled");
      goto ret_error;
    }
  else if (parser->in_transaction & TM_STMT_ATTR_RELAXED)
    {
      error_at (loc, "%<__transaction_cancel%> within a "
                "%<__transaction_relaxed%>");
      goto ret_error;
    }
  else if (is_outer)
    {
      if ((parser->in_transaction & TM_STMT_ATTR_OUTER) == 0
          && !is_tm_may_cancel_outer (current_function_decl))
        {
          error_at (loc, "outer %<__transaction_cancel%> not "
                    "within outer %<__transaction_atomic%> or "
                    "a %<transaction_may_cancel_outer%> function");
          goto ret_error;
        }
    }
  else if (parser->in_transaction == 0)
    {
      error_at (loc, "%<__transaction_cancel%> not within "
                "%<__transaction_atomic%>");
      goto ret_error;
    }

  return add_stmt (build_tm_abort_call (loc, is_outer));

 ret_error:
  return build1 (NOP_EXPR, void_type_node, error_mark_node);
}
\f
/* Parse a single source file.  */

void
c_parse_file (void)
{
  /* Use local storage to begin.  If the first token is a pragma, parse it.
     If it is #pragma GCC pch_preprocess, then this will load a PCH file
     which will cause garbage collection.  */
  c_parser tparser;

  memset (&tparser, 0, sizeof tparser);
  tparser.translate_strings_p = true;
  tparser.tokens = &tparser.tokens_buf[0];
  the_parser = &tparser;

  if (c_parser_peek_token (&tparser)->pragma_kind == PRAGMA_GCC_PCH_PREPROCESS)
    c_parser_pragma_pch_preprocess (&tparser);
  else
    c_common_no_more_pch ();

  the_parser = ggc_alloc<c_parser> ();
  *the_parser = tparser;
  if (tparser.tokens == &tparser.tokens_buf[0])
    the_parser->tokens = &the_parser->tokens_buf[0];

  /* Initialize EH, if we've been told to do so.  */
  if (flag_exceptions)
    using_eh_for_cleanups ();

  c_parser_translation_unit (the_parser);
  the_parser = NULL;
}

void
c_init_preprocess (void)
{
  /* Create a parser for use by pragma_lex during preprocessing.  */
  the_parser = ggc_alloc<c_parser> ();
  memset (the_parser, 0, sizeof (c_parser));
  the_parser->tokens = &the_parser->tokens_buf[0];
}

/* Parse the body of a function declaration marked with "__RTL".

   The RTL parser works on the level of characters read from a
   FILE *, whereas c_parser works at the level of tokens.
   Square this circle by consuming all of the tokens up to and
   including the closing brace, recording the start/end of the RTL
   fragment, and reopening the file and re-reading the relevant
   lines within the RTL parser.

   This requires the opening and closing braces of the C function
   to be on separate lines from the RTL they wrap.

   Take ownership of START_WITH_PASS, if non-NULL.  */

location_t
c_parser_parse_rtl_body (c_parser *parser, char *start_with_pass)
{
  if (!c_parser_require (parser, CPP_OPEN_BRACE, "expected %<{%>"))
    {
      free (start_with_pass);
      return c_parser_peek_token (parser)->location;
    }

  location_t start_loc = c_parser_peek_token (parser)->location;

  /* Consume all tokens, up to the closing brace, handling
     matching pairs of braces in the rtl dump.  */
  int num_open_braces = 1;
  while (1)
    {
      switch (c_parser_peek_token (parser)->type)
        {
        case CPP_OPEN_BRACE:
          num_open_braces++;
          break;
        case CPP_CLOSE_BRACE:
          if (--num_open_braces == 0)
            goto found_closing_brace;
          break;
        case CPP_EOF:
          error_at (start_loc, "no closing brace");
          free (start_with_pass);
          return c_parser_peek_token (parser)->location;
        default:
          break;
        }
      c_parser_consume_token (parser);
    }

 found_closing_brace:
  /* At the closing brace; record its location.  */
  location_t end_loc = c_parser_peek_token (parser)->location;

  /* Consume the closing brace.  */
  c_parser_consume_token (parser);

  /* Invoke the RTL parser.  */
  if (!read_rtl_function_body_from_file_range (start_loc, end_loc))
    {
      free (start_with_pass);
      return end_loc;
    }

 /*  Run the backend on the cfun created above, transferring ownership of
     START_WITH_PASS.  */
  run_rtl_passes (start_with_pass);
  return end_loc;
}

#include "gt-c-c-parser.h"