gcc/c/c-tree.h

   1 /* Definitions for C parsing and type checking.
   2    Copyright (C) 1987-2016 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_C_TREE_H
  21 #define GCC_C_TREE_H
  22
  23 #include "c-family/c-common.h"
  24 #include "diagnostic.h"
  25
  26 /* struct lang_identifier is private to c-decl.c, but langhooks.c needs to
  27    know how big it is.  This is sanity-checked in c-decl.c.  */
  28 #define C_SIZEOF_STRUCT_LANG_IDENTIFIER \
  29   (sizeof (struct c_common_identifier) + 3 * sizeof (void *))
  30
  31 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
  32 #define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1 (TYPE)
  33
  34 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile.  */
  35 #define C_TYPE_FIELDS_VOLATILE(TYPE) TREE_LANG_FLAG_2 (TYPE)
  36
  37 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  38    nonzero if the definition of the type has already started.  */
  39 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
  40
  41 /* In an incomplete RECORD_TYPE or UNION_TYPE, a list of variable
  42    declarations whose type would be completed by completing that type.  */
  43 #define C_TYPE_INCOMPLETE_VARS(TYPE) TYPE_VFIELD (TYPE)
  44
  45 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
  46    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword,
  47    and C_RID_YYCODE is the token number wanted by Yacc.  */
  48 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
  49
  50 /* Record whether a type or decl was written with nonconstant size.
  51    Note that TYPE_SIZE may have simplified to a constant.  */
  52 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
  53 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
  54
  55 /* Record whether a type is defined inside a struct or union type.
  56    This is used for -Wc++-compat. */
  57 #define C_TYPE_DEFINED_IN_STRUCT(TYPE) TYPE_LANG_FLAG_2 (TYPE)
  58
  59 /* Record whether an "incomplete type" error was given for the type.  */
  60 #define C_TYPE_ERROR_REPORTED(TYPE) TYPE_LANG_FLAG_3 (TYPE)
  61
  62 /* Record whether a typedef for type `int' was actually `signed int'.  */
  63 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
  64
  65 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
  66    return type.  */
  67 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
  68
  69 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
  70 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
  71
  72 /* For a PARM_DECL, nonzero if it was declared as an array.  */
  73 #define C_ARRAY_PARAMETER(NODE) DECL_LANG_FLAG_0 (NODE)
  74
  75 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
  76    been declared.  */
  77 #define C_DECL_DECLARED_BUILTIN(EXP)            \
  78   DECL_LANG_FLAG_3 (FUNCTION_DECL_CHECK (EXP))
  79
  80 /* For FUNCTION_DECLs, evaluates true if the decl is built-in, has a
  81    built-in prototype and does not have a non-built-in prototype.  */
  82 #define C_DECL_BUILTIN_PROTOTYPE(EXP)           \
  83   DECL_LANG_FLAG_6 (FUNCTION_DECL_CHECK (EXP))
  84
  85 /* Record whether a decl was declared register.  This is strictly a
  86    front-end flag, whereas DECL_REGISTER is used for code generation;
  87    they may differ for structures with volatile fields.  */
  88 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
  89
  90 /* Record whether a decl was used in an expression anywhere except an
  91    unevaluated operand of sizeof / typeof / alignof.  This is only
  92    used for functions declared static but not defined, though outside
  93    sizeof and typeof it is set for other function decls as well.  */
  94 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (FUNCTION_DECL_CHECK (EXP))
  95
  96 /* Record whether a variable has been declared threadprivate by
  97    #pragma omp threadprivate.  */
  98 #define C_DECL_THREADPRIVATE_P(DECL) DECL_LANG_FLAG_3 (VAR_DECL_CHECK (DECL))
  99
 100 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
 101    N.B. Could be simplified if all built-in decls had complete prototypes
 102    (but this is presently difficult because some of them need FILE*).  */
 103 #define C_DECL_ISNT_PROTOTYPE(EXP)                      \
 104        (EXP == 0                                        \
 105         || (!prototype_p (TREE_TYPE (EXP))      \
 106             && !DECL_BUILT_IN (EXP)))
 107
 108 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 109    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 110    without prototypes.  */
 111 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_LANG_SLOT_1 (NODE)
 112
 113 /* For a CONSTRUCTOR, whether some initializer contains a
 114    subexpression meaning it is not a constant expression.  */
 115 #define CONSTRUCTOR_NON_CONST(EXPR) TREE_LANG_FLAG_1 (CONSTRUCTOR_CHECK (EXPR))
 116
 117 /* Record parser information about an expression that is irrelevant
 118    for code generation alongside a tree representing its value.  */
 119 struct c_expr
 120 {
 121   /* The value of the expression.  */
 122   tree value;
 123   /* Record the original unary/binary operator of an expression, which may
 124      have been changed by fold, STRING_CST for unparenthesized string
 125      constants, C_MAYBE_CONST_EXPR for __builtin_constant_p calls
 126      (even if parenthesized), for subexpressions, and for non-constant
 127      initializers, or ERROR_MARK for other expressions (including
 128      parenthesized expressions).  */
 129   enum tree_code original_code;
 130   /* If not NULL, the original type of an expression.  This will
 131      differ from the type of the value field for an enum constant.
 132      The type of an enum constant is a plain integer type, but this
 133      field will be the enum type.  */
 134   tree original_type;
 135
 136   /* The source range of this expression.  This is redundant
 137      for node values that have locations, but not all node kinds
 138      have locations (e.g. constants, and references to params, locals,
 139      etc), so we stash a copy here.  */
 140   source_range src_range;
 141
 142   /* Access to the first and last locations within the source spelling
 143      of this expression.  */
 144   location_t get_start () const { return src_range.m_start; }
 145   location_t get_finish () const { return src_range.m_finish; }
 146
 147   /* Set the value to error_mark_node whilst ensuring that src_range
 148      is initialized.  */
 149   void set_error ()
 150   {
 151     value = error_mark_node;
 152     src_range.m_start = UNKNOWN_LOCATION;
 153     src_range.m_finish = UNKNOWN_LOCATION;
 154   }
 155 };
 156
 157 /* Type alias for struct c_expr. This allows to use the structure
 158    inside the VEC types.  */
 159 typedef struct c_expr c_expr_t;
 160
 161 /* A kind of type specifier.  Note that this information is currently
 162    only used to distinguish tag definitions, tag references and typeof
 163    uses.  */
 164 enum c_typespec_kind {
 165   /* No typespec.  This appears only in struct c_declspec.  */
 166   ctsk_none,
 167   /* A reserved keyword type specifier.  */
 168   ctsk_resword,
 169   /* A reference to a tag, previously declared, such as "struct foo".
 170      This includes where the previous declaration was as a different
 171      kind of tag, in which case this is only valid if shadowing that
 172      tag in an inner scope.  */
 173   ctsk_tagref,
 174   /* A reference to a tag, not previously declared in a visible
 175      scope.  */
 176   ctsk_tagfirstref,
 177   /* A definition of a tag such as "struct foo { int a; }".  */
 178   ctsk_tagdef,
 179   /* A typedef name.  */
 180   ctsk_typedef,
 181   /* An ObjC-specific kind of type specifier.  */
 182   ctsk_objc,
 183   /* A typeof specifier, or _Atomic ( type-name ).  */
 184   ctsk_typeof
 185 };
 186
 187 /* A type specifier: this structure is created in the parser and
 188    passed to declspecs_add_type only.  */
 189 struct c_typespec {
 190   /* What kind of type specifier this is.  */
 191   enum c_typespec_kind kind;
 192   /* Whether the expression has operands suitable for use in constant
 193      expressions.  */
 194   bool expr_const_operands;
 195   /* The specifier itself.  */
 196   tree spec;
 197   /* An expression to be evaluated before the type specifier, in the
 198      case of typeof specifiers, or NULL otherwise or if no such
 199      expression is required for a particular typeof specifier.  In
 200      particular, when typeof is applied to an expression of variably
 201      modified type, that expression must be evaluated in order to
 202      determine array sizes that form part of the type, but the
 203      expression itself (as opposed to the array sizes) forms no part
 204      of the type and so needs to be recorded separately.  */
 205   tree expr;
 206 };
 207
 208 /* A storage class specifier.  */
 209 enum c_storage_class {
 210   csc_none,
 211   csc_auto,
 212   csc_extern,
 213   csc_register,
 214   csc_static,
 215   csc_typedef
 216 };
 217
 218 /* A type specifier keyword "void", "_Bool", "char", "int", "float",
 219    "double", "_Decimal32", "_Decimal64", "_Decimal128", "_Fract", "_Accum",
 220    or none of these.  */
 221 enum c_typespec_keyword {
 222   cts_none,
 223   cts_void,
 224   cts_bool,
 225   cts_char,
 226   cts_int,
 227   cts_float,
 228   cts_int_n,
 229   cts_double,
 230   cts_dfloat32,
 231   cts_dfloat64,
 232   cts_dfloat128,
 233   cts_floatn_nx,
 234   cts_fract,
 235   cts_accum,
 236   cts_auto_type
 237 };
 238
 239 /* This enum lists all the possible declarator specifiers, storage
 240    class or attribute that a user can write.  There is at least one
 241    enumerator per possible declarator specifier in the struct
 242    c_declspecs below.
 243
 244    It is used to index the array of declspec locations in struct
 245    c_declspecs.  */
 246 enum c_declspec_word {
 247   cdw_typespec /* A catch-all for a typespec.  */,
 248   cdw_storage_class  /* A catch-all for a storage class */,
 249   cdw_attributes,
 250   cdw_typedef,
 251   cdw_explicit_signed,
 252   cdw_deprecated,
 253   cdw_default_int,
 254   cdw_long,
 255   cdw_long_long,
 256   cdw_short,
 257   cdw_signed,
 258   cdw_unsigned,
 259   cdw_complex,
 260   cdw_inline,
 261   cdw_noreturn,
 262   cdw_thread,
 263   cdw_const,
 264   cdw_volatile,
 265   cdw_restrict,
 266   cdw_atomic,
 267   cdw_saturating,
 268   cdw_alignas,
 269   cdw_address_space,
 270   cdw_gimple,
 271   cdw_number_of_elements /* This one must always be the last
 272                             enumerator.  */
 273 };
 274
 275 /* A sequence of declaration specifiers in C.  When a new declaration
 276    specifier is added, please update the enum c_declspec_word above
 277    accordingly.  */
 278 struct c_declspecs {
 279   source_location locations[cdw_number_of_elements];
 280   /* The type specified, if a single type specifier such as a struct,
 281      union or enum specifier, typedef name or typeof specifies the
 282      whole type, or NULL_TREE if none or a keyword such as "void" or
 283      "char" is used.  Does not include qualifiers.  */
 284   tree type;
 285   /* Any expression to be evaluated before the type, from a typeof
 286      specifier.  */
 287   tree expr;
 288   /* The attributes from a typedef decl.  */
 289   tree decl_attr;
 290   /* When parsing, the attributes.  Outside the parser, this will be
 291      NULL; attributes (possibly from multiple lists) will be passed
 292      separately.  */
 293   tree attrs;
 294   /* The pass to start compiling a __GIMPLE function with.  */
 295   char *gimple_pass;
 296   /* The base-2 log of the greatest alignment required by an _Alignas
 297      specifier, in bytes, or -1 if no such specifiers with nonzero
 298      alignment.  */
 299   int align_log;
 300   /* For the __intN declspec, this stores the index into the int_n_* arrays.  */
 301   int int_n_idx;
 302   /* For the _FloatN and _FloatNx declspec, this stores the index into
 303      the floatn_nx_types array.  */
 304   int floatn_nx_idx;
 305   /* The storage class specifier, or csc_none if none.  */
 306   enum c_storage_class storage_class;
 307   /* Any type specifier keyword used such as "int", not reflecting
 308      modifiers such as "short", or cts_none if none.  */
 309   ENUM_BITFIELD (c_typespec_keyword) typespec_word : 8;
 310   /* The kind of type specifier if one has been seen, ctsk_none
 311      otherwise.  */
 312   ENUM_BITFIELD (c_typespec_kind) typespec_kind : 3;
 313   /* Whether any expressions in typeof specifiers may appear in
 314      constant expressions.  */
 315   BOOL_BITFIELD expr_const_operands : 1;
 316   /* Whether any declaration specifiers have been seen at all.  */
 317   BOOL_BITFIELD declspecs_seen_p : 1;
 318   /* Whether something other than a storage class specifier or
 319      attribute has been seen.  This is used to warn for the
 320      obsolescent usage of storage class specifiers other than at the
 321      start of the list.  (Doing this properly would require function
 322      specifiers to be handled separately from storage class
 323      specifiers.)  */
 324   BOOL_BITFIELD non_sc_seen_p : 1;
 325   /* Whether the type is specified by a typedef or typeof name.  */
 326   BOOL_BITFIELD typedef_p : 1;
 327   /* Whether the type is explicitly "signed" or specified by a typedef
 328      whose type is explicitly "signed".  */
 329   BOOL_BITFIELD explicit_signed_p : 1;
 330   /* Whether the specifiers include a deprecated typedef.  */
 331   BOOL_BITFIELD deprecated_p : 1;
 332   /* Whether the type defaulted to "int" because there were no type
 333      specifiers.  */
 334   BOOL_BITFIELD default_int_p : 1;
 335   /* Whether "long" was specified.  */
 336   BOOL_BITFIELD long_p : 1;
 337   /* Whether "long" was specified more than once.  */
 338   BOOL_BITFIELD long_long_p : 1;
 339   /* Whether "short" was specified.  */
 340   BOOL_BITFIELD short_p : 1;
 341   /* Whether "signed" was specified.  */
 342   BOOL_BITFIELD signed_p : 1;
 343   /* Whether "unsigned" was specified.  */
 344   BOOL_BITFIELD unsigned_p : 1;
 345   /* Whether "complex" was specified.  */
 346   BOOL_BITFIELD complex_p : 1;
 347   /* Whether "inline" was specified.  */
 348   BOOL_BITFIELD inline_p : 1;
 349   /* Whether "_Noreturn" was speciied.  */
 350   BOOL_BITFIELD noreturn_p : 1;
 351   /* Whether "__thread" or "_Thread_local" was specified.  */
 352   BOOL_BITFIELD thread_p : 1;
 353   /* Whether "__thread" rather than "_Thread_local" was specified.  */
 354   BOOL_BITFIELD thread_gnu_p : 1;
 355   /* Whether "const" was specified.  */
 356   BOOL_BITFIELD const_p : 1;
 357   /* Whether "volatile" was specified.  */
 358   BOOL_BITFIELD volatile_p : 1;
 359   /* Whether "restrict" was specified.  */
 360   BOOL_BITFIELD restrict_p : 1;
 361   /* Whether "_Atomic" was specified.  */
 362   BOOL_BITFIELD atomic_p : 1;
 363   /* Whether "_Sat" was specified.  */
 364   BOOL_BITFIELD saturating_p : 1;
 365   /* Whether any alignment specifier (even with zero alignment) was
 366      specified.  */
 367   BOOL_BITFIELD alignas_p : 1;
 368   /* Whether any __GIMPLE specifier was specified.  */
 369   BOOL_BITFIELD gimple_p : 1;
 370   /* The address space that the declaration belongs to.  */
 371   addr_space_t address_space;
 372 };
 373
 374 /* The various kinds of declarators in C.  */
 375 enum c_declarator_kind {
 376   /* An identifier.  */
 377   cdk_id,
 378   /* A function.  */
 379   cdk_function,
 380   /* An array.  */
 381   cdk_array,
 382   /* A pointer.  */
 383   cdk_pointer,
 384   /* Parenthesized declarator with nested attributes.  */
 385   cdk_attrs
 386 };
 387
 388 struct c_arg_tag {
 389   /* The argument name.  */
 390   tree id;
 391   /* The type of the argument.  */
 392   tree type;
 393 };
 394
 395
 396 /* Information about the parameters in a function declarator.  */
 397 struct c_arg_info {
 398   /* A list of parameter decls.  */
 399   tree parms;
 400   /* A list of structure, union and enum tags defined.  */
 401   vec<c_arg_tag, va_gc> *tags;
 402   /* A list of argument types to go in the FUNCTION_TYPE.  */
 403   tree types;
 404   /* A list of non-parameter decls (notably enumeration constants)
 405      defined with the parameters.  */
 406   tree others;
 407   /* A compound expression of VLA sizes from the parameters, or NULL.
 408      In a function definition, these are used to ensure that
 409      side-effects in sizes of arrays converted to pointers (such as a
 410      parameter int i[n++]) take place; otherwise, they are
 411      ignored.  */
 412   tree pending_sizes;
 413   /* True when these arguments had [*].  */
 414   BOOL_BITFIELD had_vla_unspec : 1;
 415 };
 416
 417 /* A declarator.  */
 418 struct c_declarator {
 419   /* The kind of declarator.  */
 420   enum c_declarator_kind kind;
 421   location_t id_loc; /* Currently only set for cdk_id, cdk_array. */
 422   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
 423   struct c_declarator *declarator;
 424   union {
 425     /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract
 426        declarator.  */
 427     tree id;
 428     /* For functions.  */
 429     struct c_arg_info *arg_info;
 430     /* For arrays.  */
 431     struct {
 432       /* The array dimension, or NULL for [] and [*].  */
 433       tree dimen;
 434       /* The qualifiers inside [].  */
 435       int quals;
 436       /* The attributes (currently ignored) inside [].  */
 437       tree attrs;
 438       /* Whether [static] was used.  */
 439       BOOL_BITFIELD static_p : 1;
 440       /* Whether [*] was used.  */
 441       BOOL_BITFIELD vla_unspec_p : 1;
 442     } array;
 443     /* For pointers, the qualifiers on the pointer type.  */
 444     int pointer_quals;
 445     /* For attributes.  */
 446     tree attrs;
 447   } u;
 448 };
 449
 450 /* A type name.  */
 451 struct c_type_name {
 452   /* The declaration specifiers.  */
 453   struct c_declspecs *specs;
 454   /* The declarator.  */
 455   struct c_declarator *declarator;
 456 };
 457
 458 /* A parameter.  */
 459 struct c_parm {
 460   /* The declaration specifiers, minus any prefix attributes.  */
 461   struct c_declspecs *specs;
 462   /* The attributes.  */
 463   tree attrs;
 464   /* The declarator.  */
 465   struct c_declarator *declarator;
 466 };
 467
 468 /* Used when parsing an enum.  Initialized by start_enum.  */
 469 struct c_enum_contents
 470 {
 471   /* While defining an enum type, this is 1 plus the last enumerator
 472      constant value.  */
 473   tree enum_next_value;
 474
 475   /* Nonzero means that there was overflow computing enum_next_value.  */
 476   int enum_overflow;
 477 };
 478
 479 /* A type of reference to a static identifier in an inline
 480    function.  */
 481 enum c_inline_static_type {
 482   /* Identifier with internal linkage used in function that may be an
 483      inline definition (i.e., file-scope static).  */
 484   csi_internal,
 485   /* Modifiable object with static storage duration defined in
 486      function that may be an inline definition (i.e., local
 487      static).  */
 488   csi_modifiable
 489 };
 490
 491 \f
 492 /* in c-parser.c */
 493 extern void c_parse_init (void);
 494 extern bool c_keyword_starts_typename (enum rid keyword);
 495
 496 /* in c-aux-info.c */
 497 extern void gen_aux_info_record (tree, int, int, int);
 498
 499 /* in c-decl.c */
 500 struct c_spot_bindings;
 501 struct c_struct_parse_info;
 502 extern struct obstack parser_obstack;
 503 extern tree c_break_label;
 504 extern tree c_cont_label;
 505
 506 extern bool global_bindings_p (void);
 507 extern void push_scope (void);
 508 extern tree pop_scope (void);
 509 extern void c_bindings_start_stmt_expr (struct c_spot_bindings *);
 510 extern void c_bindings_end_stmt_expr (struct c_spot_bindings *);
 511
 512 extern void record_inline_static (location_t, tree, tree,
 513                                   enum c_inline_static_type);
 514 extern void c_init_decl_processing (void);
 515 extern void c_print_identifier (FILE *, tree, int);
 516 extern int quals_from_declspecs (const struct c_declspecs *);
 517 extern struct c_declarator *build_array_declarator (location_t, tree,
 518                                                     struct c_declspecs *,
 519                                                     bool, bool);
 520 extern tree build_enumerator (location_t, location_t, struct c_enum_contents *,
 521                               tree, tree);
 522 extern tree check_for_loop_decls (location_t, bool);
 523 extern void mark_forward_parm_decls (void);
 524 extern void declare_parm_level (void);
 525 extern void undeclared_variable (location_t, tree);
 526 extern tree lookup_label_for_goto (location_t, tree);
 527 extern tree declare_label (tree);
 528 extern tree define_label (location_t, tree);
 529 extern struct c_spot_bindings *c_get_switch_bindings (void);
 530 extern void c_release_switch_bindings (struct c_spot_bindings *);
 531 extern bool c_check_switch_jump_warnings (struct c_spot_bindings *,
 532                                           location_t, location_t);
 533 extern void finish_decl (tree, location_t, tree, tree, tree);
 534 extern tree finish_enum (tree, tree, tree);
 535 extern void finish_function (void);
 536 extern tree finish_struct (location_t, tree, tree, tree,
 537                            struct c_struct_parse_info *);
 538 extern struct c_arg_info *build_arg_info (void);
 539 extern struct c_arg_info *get_parm_info (bool, tree);
 540 extern tree grokfield (location_t, struct c_declarator *,
 541                        struct c_declspecs *, tree, tree *);
 542 extern tree groktypename (struct c_type_name *, tree *, bool *);
 543 extern tree grokparm (const struct c_parm *, tree *);
 544 extern tree implicitly_declare (location_t, tree);
 545 extern void keep_next_level (void);
 546 extern void pending_xref_error (void);
 547 extern void c_push_function_context (void);
 548 extern void c_pop_function_context (void);
 549 extern void push_parm_decl (const struct c_parm *, tree *);
 550 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
 551                                                         struct c_declarator *);
 552 extern tree c_builtin_function (tree);
 553 extern tree c_builtin_function_ext_scope (tree);
 554 extern void shadow_tag (const struct c_declspecs *);
 555 extern void shadow_tag_warned (const struct c_declspecs *, int);
 556 extern tree start_enum (location_t, struct c_enum_contents *, tree);
 557 extern int  start_function (struct c_declspecs *, struct c_declarator *, tree);
 558 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
 559                         tree);
 560 extern tree start_struct (location_t, enum tree_code, tree,
 561                           struct c_struct_parse_info **);
 562 extern void store_parm_decls (void);
 563 extern void store_parm_decls_from (struct c_arg_info *);
 564 extern void temp_store_parm_decls (tree, tree);
 565 extern void temp_pop_parm_decls (void);
 566 extern tree xref_tag (enum tree_code, tree);
 567 extern struct c_typespec parser_xref_tag (location_t, enum tree_code, tree);
 568 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
 569                                     struct c_declarator *);
 570 extern struct c_declarator *build_attrs_declarator (tree,
 571                                                     struct c_declarator *);
 572 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
 573                                                        struct c_declarator *);
 574 extern struct c_declarator *build_id_declarator (tree);
 575 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
 576                                                      struct c_declarator *);
 577 extern struct c_declspecs *build_null_declspecs (void);
 578 extern struct c_declspecs *declspecs_add_qual (source_location,
 579                                                struct c_declspecs *, tree);
 580 extern struct c_declspecs *declspecs_add_type (location_t,
 581                                                struct c_declspecs *,
 582                                                struct c_typespec);
 583 extern struct c_declspecs *declspecs_add_scspec (source_location,
 584                                                  struct c_declspecs *, tree);
 585 extern struct c_declspecs *declspecs_add_attrs (source_location,
 586                                                 struct c_declspecs *, tree);
 587 extern struct c_declspecs *declspecs_add_addrspace (source_location,
 588                                                     struct c_declspecs *,
 589                                                     addr_space_t);
 590 extern struct c_declspecs *declspecs_add_alignas (source_location,
 591                                                   struct c_declspecs *, tree);
 592 extern struct c_declspecs *finish_declspecs (struct c_declspecs *);
 593
 594 /* in c-objc-common.c */
 595 extern bool c_objc_common_init (void);
 596 extern bool c_missing_noreturn_ok_p (tree);
 597 extern bool c_warn_unused_global_decl (const_tree);
 598 extern void c_initialize_diagnostics (diagnostic_context *);
 599 extern bool c_vla_unspec_p (tree x, tree fn);
 600
 601 /* in c-typeck.c */
 602 extern int in_alignof;
 603 extern int in_sizeof;
 604 extern int in_typeof;
 605
 606 extern tree c_last_sizeof_arg;
 607
 608 extern struct c_switch *c_switch_stack;
 609
 610 extern tree c_objc_common_truthvalue_conversion (location_t, tree);
 611 extern tree require_complete_type (location_t, tree);
 612 extern int same_translation_unit_p (const_tree, const_tree);
 613 extern int comptypes (tree, tree);
 614 extern int comptypes_check_different_types (tree, tree, bool *);
 615 extern bool c_vla_type_p (const_tree);
 616 extern bool c_mark_addressable (tree);
 617 extern void c_incomplete_type_error (location_t, const_tree, const_tree);
 618 extern tree c_type_promotes_to (tree);
 619 extern struct c_expr default_function_array_conversion (location_t,
 620                                                         struct c_expr);
 621 extern struct c_expr default_function_array_read_conversion (location_t,
 622                                                              struct c_expr);
 623 extern struct c_expr convert_lvalue_to_rvalue (location_t, struct c_expr,
 624                                                bool, bool);
 625 extern void mark_exp_read (tree);
 626 extern tree composite_type (tree, tree);
 627 extern tree build_component_ref (location_t, tree, tree, location_t);
 628 extern tree build_array_ref (location_t, tree, tree);
 629 extern tree build_external_ref (location_t, tree, int, tree *);
 630 extern void pop_maybe_used (bool);
 631 extern struct c_expr c_expr_sizeof_expr (location_t, struct c_expr);
 632 extern struct c_expr c_expr_sizeof_type (location_t, struct c_type_name *);
 633 extern struct c_expr parser_build_unary_op (location_t, enum tree_code,
 634                                             struct c_expr);
 635 extern struct c_expr parser_build_binary_op (location_t,
 636                                              enum tree_code, struct c_expr,
 637                                              struct c_expr);
 638 extern tree build_conditional_expr (location_t, tree, bool, tree, tree,
 639                                     tree, tree);
 640 extern tree build_compound_expr (location_t, tree, tree);
 641 extern tree c_cast_expr (location_t, struct c_type_name *, tree);
 642 extern tree build_c_cast (location_t, tree, tree);
 643 extern void store_init_value (location_t, tree, tree, tree);
 644 extern void maybe_warn_string_init (location_t, tree, struct c_expr);
 645 extern void start_init (tree, tree, int);
 646 extern void finish_init (void);
 647 extern void really_start_incremental_init (tree);
 648 extern void finish_implicit_inits (location_t, struct obstack *);
 649 extern void push_init_level (location_t, int, struct obstack *);
 650 extern struct c_expr pop_init_level (location_t, int, struct obstack *);
 651 extern void set_init_index (location_t, tree, tree, struct obstack *);
 652 extern void set_init_label (location_t, tree, location_t, struct obstack *);
 653 extern void process_init_element (location_t, struct c_expr, bool,
 654                                   struct obstack *);
 655 extern tree build_compound_literal (location_t, tree, tree, bool);
 656 extern void check_compound_literal_type (location_t, struct c_type_name *);
 657 extern tree c_start_case (location_t, location_t, tree, bool);
 658 extern void c_finish_case (tree, tree);
 659 extern tree build_asm_expr (location_t, tree, tree, tree, tree, tree, bool);
 660 extern tree build_asm_stmt (tree, tree);
 661 extern int c_types_compatible_p (tree, tree);
 662 extern tree c_begin_compound_stmt (bool);
 663 extern tree c_end_compound_stmt (location_t, tree, bool);
 664 extern void c_finish_if_stmt (location_t, tree, tree, tree);
 665 extern void c_finish_loop (location_t, tree, tree, tree, tree, tree, bool);
 666 extern tree c_begin_stmt_expr (void);
 667 extern tree c_finish_stmt_expr (location_t, tree);
 668 extern tree c_process_expr_stmt (location_t, tree);
 669 extern tree c_finish_expr_stmt (location_t, tree);
 670 extern tree c_finish_return (location_t, tree, tree);
 671 extern tree c_finish_bc_stmt (location_t, tree *, bool);
 672 extern tree c_finish_goto_label (location_t, tree);
 673 extern tree c_finish_goto_ptr (location_t, tree);
 674 extern tree c_expr_to_decl (tree, bool *, bool *);
 675 extern tree c_finish_omp_construct (location_t, enum tree_code, tree, tree);
 676 extern tree c_finish_oacc_data (location_t, tree, tree);
 677 extern tree c_finish_oacc_host_data (location_t, tree, tree);
 678 extern tree c_begin_omp_parallel (void);
 679 extern tree c_finish_omp_parallel (location_t, tree, tree);
 680 extern tree c_begin_omp_task (void);
 681 extern tree c_finish_omp_task (location_t, tree, tree);
 682 extern void c_finish_omp_cancel (location_t, tree);
 683 extern void c_finish_omp_cancellation_point (location_t, tree);
 684 extern tree c_finish_omp_clauses (tree, enum c_omp_region_type);
 685 extern tree c_build_va_arg (location_t, tree, location_t, tree);
 686 extern tree c_finish_transaction (location_t, tree, int);
 687 extern bool c_tree_equal (tree, tree);
 688 extern tree c_build_function_call_vec (location_t, vec<location_t>, tree,
 689                                        vec<tree, va_gc> *, vec<tree, va_gc> *);
 690 extern tree c_omp_clause_copy_ctor (tree, tree, tree);
 691
 692 /* Set to 0 at beginning of a function definition, set to 1 if
 693    a return statement that specifies a return value is seen.  */
 694
 695 extern int current_function_returns_value;
 696
 697 /* Set to 0 at beginning of a function definition, set to 1 if
 698    a return statement with no argument is seen.  */
 699
 700 extern int current_function_returns_null;
 701
 702 /* Set to 0 at beginning of a function definition, set to 1 if
 703    a call to a noreturn function is seen.  */
 704
 705 extern int current_function_returns_abnormally;
 706
 707 /* In c-decl.c */
 708
 709 /* Tell the binding oracle what kind of binding we are looking for.  */
 710
 711 enum c_oracle_request
 712 {
 713   C_ORACLE_SYMBOL,
 714   C_ORACLE_TAG,
 715   C_ORACLE_LABEL
 716 };
 717
 718 /* If this is non-NULL, then it is a "binding oracle" which can lazily
 719    create bindings when needed by the C compiler.  The oracle is told
 720    the name and type of the binding to create.  It can call pushdecl
 721    or the like to ensure the binding is visible; or do nothing,
 722    leaving the binding untouched.  c-decl.c takes note of when the
 723    oracle has been called and will not call it again if it fails to
 724    create a given binding.  */
 725
 726 typedef void c_binding_oracle_function (enum c_oracle_request, tree identifier);
 727
 728 extern c_binding_oracle_function *c_binding_oracle;
 729
 730 extern void c_finish_incomplete_decl (tree);
 731 extern tree c_omp_reduction_id (enum tree_code, tree);
 732 extern tree c_omp_reduction_decl (tree);
 733 extern tree c_omp_reduction_lookup (tree, tree);
 734 extern tree c_check_omp_declare_reduction_r (tree *, int *, void *);
 735 extern void c_pushtag (location_t, tree, tree);
 736 extern void c_bind (location_t, tree, bool);
 737 extern bool tag_exists_p (enum tree_code, tree);
 738
 739 /* In c-errors.c */
 740 extern bool pedwarn_c90 (location_t, int opt, const char *, ...)
 741     ATTRIBUTE_GCC_DIAG(3,4);
 742 extern bool pedwarn_c99 (location_t, int opt, const char *, ...)
 743     ATTRIBUTE_GCC_DIAG(3,4);
 744
 745 extern void
 746 set_c_expr_source_range (c_expr *expr,
 747                          location_t start, location_t finish);
 748
 749 extern void
 750 set_c_expr_source_range (c_expr *expr,
 751                          source_range src_range);
 752
 753 /* In c-fold.c */
 754 extern tree decl_constant_value_for_optimization (tree);
 755
 756 extern vec<tree> incomplete_record_decls;
 757
 758 #endif /* ! GCC_C_TREE_H */