gcc/c/c-tree.h

   1 /* Definitions for C parsing and type checking.
   2    Copyright (C) 1987-2023 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.cc, but langhooks.cc needs to
  27    know how big it is.  This is sanity-checked in c-decl.cc.  */
  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, nonzero if any component is
  38    volatile, restrict-qualified or atomic; that is, has a type not
  39    permitted for a constexpr object.  */
  40 #define C_TYPE_FIELDS_NON_CONSTEXPR(TYPE) TREE_LANG_FLAG_4 (TYPE)
  41
  42 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  43    nonzero if the definition of the type has already started.  */
  44 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
  45
  46 /* In an incomplete RECORD_TYPE, UNION_TYPE or ENUMERAL_TYPE, a list of
  47    variable declarations whose type would be completed by completing
  48    that type.  */
  49 #define C_TYPE_INCOMPLETE_VARS(TYPE) \
  50   TYPE_LANG_SLOT_1 (TREE_CHECK4 (TYPE, RECORD_TYPE, UNION_TYPE, \
  51                                  QUAL_UNION_TYPE, ENUMERAL_TYPE))
  52
  53 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
  54    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword.  */
  55 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
  56
  57 /* Record whether a type or decl was written with nonconstant size.
  58    Note that TYPE_SIZE may have simplified to a constant.  */
  59 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
  60 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
  61
  62 /* Record whether a type is variably modified. */
  63 #define C_TYPE_VARIABLY_MODIFIED(TYPE) TYPE_LANG_FLAG_6 (TYPE)
  64
  65
  66 /* Record whether a type is defined inside a struct or union type.
  67    This is used for -Wc++-compat. */
  68 #define C_TYPE_DEFINED_IN_STRUCT(TYPE) TYPE_LANG_FLAG_2 (TYPE)
  69
  70 /* Record whether a typedef for type `int' was actually `signed int'.  */
  71 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
  72
  73 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
  74    return type.  */
  75 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
  76
  77 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
  78 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
  79
  80 /* For a PARM_DECL, nonzero if it was declared as an array.  */
  81 #define C_ARRAY_PARAMETER(NODE) DECL_LANG_FLAG_0 (NODE)
  82
  83 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
  84    been declared.  */
  85 #define C_DECL_DECLARED_BUILTIN(EXP)            \
  86   DECL_LANG_FLAG_3 (FUNCTION_DECL_CHECK (EXP))
  87
  88 /* For FUNCTION_DECLs, evaluates true if the decl is built-in, has a
  89    built-in prototype and does not have a non-built-in prototype.  */
  90 #define C_DECL_BUILTIN_PROTOTYPE(EXP)           \
  91   DECL_LANG_FLAG_6 (FUNCTION_DECL_CHECK (EXP))
  92
  93 /* Record whether a decl was declared register.  This is strictly a
  94    front-end flag, whereas DECL_REGISTER is used for code generation;
  95    they may differ for structures with volatile fields.  */
  96 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
  97
  98 /* Record whether a decl was used in an expression anywhere except an
  99    unevaluated operand of sizeof / typeof / alignof.  This is only
 100    used for functions declared static but not defined, though outside
 101    sizeof and typeof it is set for other function decls as well.  */
 102 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (FUNCTION_DECL_CHECK (EXP))
 103
 104 /* Record whether a variable has been declared threadprivate by
 105    #pragma omp threadprivate.  */
 106 #define C_DECL_THREADPRIVATE_P(DECL) DECL_LANG_FLAG_3 (VAR_DECL_CHECK (DECL))
 107
 108 /* Set on VAR_DECLs for compound literals.  */
 109 #define C_DECL_COMPOUND_LITERAL_P(DECL) \
 110   DECL_LANG_FLAG_5 (VAR_DECL_CHECK (DECL))
 111
 112 /* Set on decls used as placeholders for a C2x underspecified object
 113    definition.  */
 114 #define C_DECL_UNDERSPECIFIED(DECL) DECL_LANG_FLAG_7 (DECL)
 115
 116 /* Set on VAR_DECLs declared as 'constexpr'.  */
 117 #define C_DECL_DECLARED_CONSTEXPR(DECL) \
 118   DECL_LANG_FLAG_8 (VAR_DECL_CHECK (DECL))
 119
 120 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
 121    N.B. Could be simplified if all built-in decls had complete prototypes
 122    (but this is presently difficult because some of them need FILE*).  */
 123 #define C_DECL_ISNT_PROTOTYPE(EXP)                      \
 124        (EXP == 0                                        \
 125         || (!prototype_p (TREE_TYPE (EXP))      \
 126             && !fndecl_built_in_p (EXP)))
 127
 128 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 129    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 130    without prototypes.  */
 131 #define TYPE_ACTUAL_ARG_TYPES(NODE) \
 132   TYPE_LANG_SLOT_1 (FUNCTION_TYPE_CHECK (NODE))
 133
 134 /* For a CONSTRUCTOR, whether some initializer contains a
 135    subexpression meaning it is not a constant expression.  */
 136 #define CONSTRUCTOR_NON_CONST(EXPR) TREE_LANG_FLAG_1 (CONSTRUCTOR_CHECK (EXPR))
 137
 138 /* For a SAVE_EXPR, nonzero if the operand of the SAVE_EXPR has already
 139    been folded.  */
 140 #define SAVE_EXPR_FOLDED_P(EXP) TREE_LANG_FLAG_1 (SAVE_EXPR_CHECK (EXP))
 141
 142 /* Whether a type has boolean semantics: either a boolean type or an
 143    enumeration type with a boolean type as its underlying type.  */
 144 #define C_BOOLEAN_TYPE_P(TYPE)                                          \
 145   (TREE_CODE (TYPE) == BOOLEAN_TYPE                                     \
 146    || (TREE_CODE (TYPE) == ENUMERAL_TYPE                                \
 147        && ENUM_UNDERLYING_TYPE (TYPE) != NULL_TREE                      \
 148        && TREE_CODE (ENUM_UNDERLYING_TYPE (TYPE)) == BOOLEAN_TYPE))
 149
 150 /* Record parser information about an expression that is irrelevant
 151    for code generation alongside a tree representing its value.  */
 152 struct c_expr
 153 {
 154   /* The value of the expression.  */
 155   tree value;
 156   /* Record the original unary/binary operator of an expression, which may
 157      have been changed by fold, STRING_CST for unparenthesized string
 158      constants, C_MAYBE_CONST_EXPR for __builtin_constant_p calls
 159      (even if parenthesized), for subexpressions, and for non-constant
 160      initializers, or ERROR_MARK for other expressions (including
 161      parenthesized expressions).  */
 162   enum tree_code original_code;
 163   /* If not NULL, the original type of an expression.  This will
 164      differ from the type of the value field for an enum constant.
 165      The type of an enum constant is a plain integer type, but this
 166      field will be the enum type.  */
 167   tree original_type;
 168
 169   /* The source range of this expression.  This is redundant
 170      for node values that have locations, but not all node kinds
 171      have locations (e.g. constants, and references to params, locals,
 172      etc), so we stash a copy here.  */
 173   source_range src_range;
 174
 175   /* True if this was directly from a decimal constant token.  */
 176   bool m_decimal : 1;
 177
 178   /* Access to the first and last locations within the source spelling
 179      of this expression.  */
 180   location_t get_start () const { return src_range.m_start; }
 181   location_t get_finish () const { return src_range.m_finish; }
 182
 183   location_t get_location () const
 184   {
 185     if (EXPR_HAS_LOCATION (value))
 186       return EXPR_LOCATION (value);
 187     else
 188       return make_location (get_start (), get_start (), get_finish ());
 189   }
 190
 191   /* Set the value to error_mark_node whilst ensuring that src_range
 192      and m_decimal are initialized.  */
 193   void set_error ()
 194   {
 195     value = error_mark_node;
 196     src_range.m_start = UNKNOWN_LOCATION;
 197     src_range.m_finish = UNKNOWN_LOCATION;
 198     m_decimal = 0;
 199   }
 200 };
 201
 202 /* Type alias for struct c_expr. This allows to use the structure
 203    inside the VEC types.  */
 204 typedef struct c_expr c_expr_t;
 205
 206 /* A kind of type specifier.  Note that this information is currently
 207    only used to distinguish tag definitions, tag references and typeof
 208    uses.  */
 209 enum c_typespec_kind {
 210   /* No typespec.  This appears only in struct c_declspec.  */
 211   ctsk_none,
 212   /* A reserved keyword type specifier.  */
 213   ctsk_resword,
 214   /* A reference to a tag, previously declared, such as "struct foo".
 215      This includes where the previous declaration was as a different
 216      kind of tag, in which case this is only valid if shadowing that
 217      tag in an inner scope.  */
 218   ctsk_tagref,
 219   /* Likewise, with standard attributes present in the reference.  */
 220   ctsk_tagref_attrs,
 221   /* A reference to a tag, not previously declared in a visible
 222      scope.  */
 223   ctsk_tagfirstref,
 224   /* Likewise, with standard attributes present in the reference.  */
 225   ctsk_tagfirstref_attrs,
 226   /* A definition of a tag such as "struct foo { int a; }".  */
 227   ctsk_tagdef,
 228   /* A typedef name.  */
 229   ctsk_typedef,
 230   /* An ObjC-specific kind of type specifier.  */
 231   ctsk_objc,
 232   /* A typeof specifier, or _Atomic ( type-name ).  */
 233   ctsk_typeof
 234 };
 235
 236 /* A type specifier: this structure is created in the parser and
 237    passed to declspecs_add_type only.  */
 238 struct c_typespec {
 239   /* What kind of type specifier this is.  */
 240   enum c_typespec_kind kind;
 241   /* Whether the expression has operands suitable for use in constant
 242      expressions.  */
 243   bool expr_const_operands;
 244   /* Whether the type specifier includes an enum type specifier (that
 245      is, ": specifier-qualifier-list" in a declaration using
 246      "enum").  */
 247   bool has_enum_type_specifier;
 248   /* The specifier itself.  */
 249   tree spec;
 250   /* An expression to be evaluated before the type specifier, in the
 251      case of typeof specifiers, or NULL otherwise or if no such
 252      expression is required for a particular typeof specifier.  In
 253      particular, when typeof is applied to an expression of variably
 254      modified type, that expression must be evaluated in order to
 255      determine array sizes that form part of the type, but the
 256      expression itself (as opposed to the array sizes) forms no part
 257      of the type and so needs to be recorded separately.  */
 258   tree expr;
 259 };
 260
 261 /* A storage class specifier.  */
 262 enum c_storage_class {
 263   csc_none,
 264   csc_auto,
 265   csc_extern,
 266   csc_register,
 267   csc_static,
 268   csc_typedef
 269 };
 270
 271 /* A type specifier keyword "void", "_Bool", "char", "int", "float",
 272    "double", "_Decimal32", "_Decimal64", "_Decimal128", "_Fract", "_Accum",
 273    or none of these.  */
 274 enum c_typespec_keyword {
 275   cts_none,
 276   cts_void,
 277   cts_bool,
 278   cts_char,
 279   cts_int,
 280   cts_float,
 281   cts_int_n,
 282   cts_double,
 283   cts_dfloat32,
 284   cts_dfloat64,
 285   cts_dfloat128,
 286   cts_floatn_nx,
 287   cts_fract,
 288   cts_accum,
 289   cts_auto_type
 290 };
 291
 292 /* This enum lists all the possible declarator specifiers, storage
 293    class or attribute that a user can write.  There is at least one
 294    enumerator per possible declarator specifier in the struct
 295    c_declspecs below.
 296
 297    It is used to index the array of declspec locations in struct
 298    c_declspecs.  */
 299 enum c_declspec_word {
 300   cdw_typespec /* A catch-all for a typespec.  */,
 301   cdw_storage_class  /* A catch-all for a storage class */,
 302   cdw_attributes,
 303   cdw_typedef,
 304   cdw_explicit_signed,
 305   cdw_deprecated,
 306   cdw_default_int,
 307   cdw_long,
 308   cdw_long_long,
 309   cdw_short,
 310   cdw_signed,
 311   cdw_unsigned,
 312   cdw_complex,
 313   cdw_inline,
 314   cdw_noreturn,
 315   cdw_thread,
 316   cdw_const,
 317   cdw_volatile,
 318   cdw_restrict,
 319   cdw_atomic,
 320   cdw_saturating,
 321   cdw_alignas,
 322   cdw_address_space,
 323   cdw_gimple,
 324   cdw_rtl,
 325   cdw_number_of_elements /* This one must always be the last
 326                             enumerator.  */
 327 };
 328
 329 enum c_declspec_il {
 330   cdil_none,
 331   cdil_gimple,          /* __GIMPLE  */
 332   cdil_gimple_cfg,      /* __GIMPLE(cfg)  */
 333   cdil_gimple_ssa,      /* __GIMPLE(ssa)  */
 334   cdil_rtl              /* __RTL  */
 335 };
 336
 337 /* A sequence of declaration specifiers in C.  When a new declaration
 338    specifier is added, please update the enum c_declspec_word above
 339    accordingly.  */
 340 struct c_declspecs {
 341   location_t locations[cdw_number_of_elements];
 342   /* The type specified, if a single type specifier such as a struct,
 343      union or enum specifier, typedef name or typeof specifies the
 344      whole type, or NULL_TREE if none or a keyword such as "void" or
 345      "char" is used.  Does not include qualifiers.  */
 346   tree type;
 347   /* Any expression to be evaluated before the type, from a typeof
 348      specifier.  */
 349   tree expr;
 350   /* The attributes from a typedef decl.  */
 351   tree decl_attr;
 352   /* When parsing, the GNU attributes and prefix standard attributes.
 353      Outside the parser, this will be NULL; attributes (possibly from
 354      multiple lists) will be passed separately.  */
 355   tree attrs;
 356   /* When parsing, postfix standard attributes (which appertain to the
 357      type specified by the preceding declaration specifiers, unlike
 358      prefix standard attributes which appertain to the declaration or
 359      declarations as a whole).  */
 360   tree postfix_attrs;
 361   /* The pass to start compiling a __GIMPLE or __RTL function with.  */
 362   char *gimple_or_rtl_pass;
 363   /* ENTRY BB count.  */
 364   profile_count entry_bb_count;
 365   /* The base-2 log of the greatest alignment required by an _Alignas
 366      specifier, in bytes, or -1 if no such specifiers with nonzero
 367      alignment.  */
 368   int align_log;
 369   /* For the __intN declspec, this stores the index into the int_n_* arrays.  */
 370   int int_n_idx;
 371   /* For the _FloatN and _FloatNx declspec, this stores the index into
 372      the floatn_nx_types array.  */
 373   int floatn_nx_idx;
 374   /* The storage class specifier, or csc_none if none.  */
 375   enum c_storage_class storage_class;
 376   /* Any type specifier keyword used such as "int", not reflecting
 377      modifiers such as "short", or cts_none if none.  */
 378   ENUM_BITFIELD (c_typespec_keyword) typespec_word : 8;
 379   /* The kind of type specifier if one has been seen, ctsk_none
 380      otherwise.  */
 381   ENUM_BITFIELD (c_typespec_kind) typespec_kind : 4;
 382   ENUM_BITFIELD (c_declspec_il) declspec_il : 3;
 383   /* Whether any expressions in typeof specifiers may appear in
 384      constant expressions.  */
 385   BOOL_BITFIELD expr_const_operands : 1;
 386   /* Whether any declaration specifiers have been seen at all.  */
 387   BOOL_BITFIELD declspecs_seen_p : 1;
 388   /* Whether any declaration specifiers other than standard attributes
 389      have been seen at all.  If only standard attributes have been
 390      seen, this is an attribute-declaration.  */
 391   BOOL_BITFIELD non_std_attrs_seen_p : 1;
 392   /* Whether something other than a storage class specifier or
 393      attribute has been seen.  This is used to warn for the
 394      obsolescent usage of storage class specifiers other than at the
 395      start of the list.  (Doing this properly would require function
 396      specifiers to be handled separately from storage class
 397      specifiers.)  */
 398   BOOL_BITFIELD non_sc_seen_p : 1;
 399   /* Whether the type is specified by a typedef or typeof name.  */
 400   BOOL_BITFIELD typedef_p : 1;
 401   /* Whether the type is explicitly "signed" or specified by a typedef
 402      whose type is explicitly "signed".  */
 403   BOOL_BITFIELD explicit_signed_p : 1;
 404   /* Whether the specifiers include a deprecated typedef.  */
 405   BOOL_BITFIELD deprecated_p : 1;
 406   /* Whether the specifiers include an unavailable typedef.  */
 407   BOOL_BITFIELD unavailable_p : 1;
 408   /* Whether the type defaulted to "int" because there were no type
 409      specifiers.  */
 410   BOOL_BITFIELD default_int_p : 1;
 411   /* Whether "long" was specified.  */
 412   BOOL_BITFIELD long_p : 1;
 413   /* Whether "long" was specified more than once.  */
 414   BOOL_BITFIELD long_long_p : 1;
 415   /* Whether "short" was specified.  */
 416   BOOL_BITFIELD short_p : 1;
 417   /* Whether "signed" was specified.  */
 418   BOOL_BITFIELD signed_p : 1;
 419   /* Whether "unsigned" was specified.  */
 420   BOOL_BITFIELD unsigned_p : 1;
 421   /* Whether "complex" was specified.  */
 422   BOOL_BITFIELD complex_p : 1;
 423   /* Whether "inline" was specified.  */
 424   BOOL_BITFIELD inline_p : 1;
 425   /* Whether "_Noreturn" was speciied.  */
 426   BOOL_BITFIELD noreturn_p : 1;
 427   /* Whether "__thread" or "_Thread_local" was specified.  */
 428   BOOL_BITFIELD thread_p : 1;
 429   /* Whether "__thread" rather than "_Thread_local" was specified.  */
 430   BOOL_BITFIELD thread_gnu_p : 1;
 431   /* Whether "const" was specified.  */
 432   BOOL_BITFIELD const_p : 1;
 433   /* Whether "volatile" was specified.  */
 434   BOOL_BITFIELD volatile_p : 1;
 435   /* Whether "restrict" was specified.  */
 436   BOOL_BITFIELD restrict_p : 1;
 437   /* Whether "_Atomic" was specified.  */
 438   BOOL_BITFIELD atomic_p : 1;
 439   /* Whether "_Sat" was specified.  */
 440   BOOL_BITFIELD saturating_p : 1;
 441   /* Whether any alignment specifier (even with zero alignment) was
 442      specified.  */
 443   BOOL_BITFIELD alignas_p : 1;
 444   /* Whether an enum type specifier (": specifier-qualifier-list") was
 445      specified other than in a definition of that enum (if so, this is
 446      invalid unless it is an empty declaration "enum identifier
 447      enum-type-specifier;", but such an empty declaration is valid in
 448      C2x when "enum identifier;" would not be).  */
 449   BOOL_BITFIELD enum_type_specifier_ref_p : 1;
 450   /* Whether "auto" was specified in C2X (or later) mode and means the
 451      type is to be deduced from an initializer, or would mean that if
 452      no type specifier appears later in these declaration
 453      specifiers.  */
 454   BOOL_BITFIELD c2x_auto_p : 1;
 455   /* Whether "constexpr" was specified.  */
 456   BOOL_BITFIELD constexpr_p : 1;
 457   /* The address space that the declaration belongs to.  */
 458   addr_space_t address_space;
 459 };
 460
 461 /* The various kinds of declarators in C.  */
 462 enum c_declarator_kind {
 463   /* An identifier.  */
 464   cdk_id,
 465   /* A function.  */
 466   cdk_function,
 467   /* An array.  */
 468   cdk_array,
 469   /* A pointer.  */
 470   cdk_pointer,
 471   /* Parenthesized declarator with nested attributes.  */
 472   cdk_attrs
 473 };
 474
 475 struct c_arg_tag {
 476   /* The argument name.  */
 477   tree id;
 478   /* The type of the argument.  */
 479   tree type;
 480 };
 481
 482
 483 /* Information about the parameters in a function declarator.  */
 484 struct c_arg_info {
 485   /* A list of parameter decls.  */
 486   tree parms;
 487   /* A list of structure, union and enum tags defined.  */
 488   vec<c_arg_tag, va_gc> *tags;
 489   /* A list of argument types to go in the FUNCTION_TYPE.  */
 490   tree types;
 491   /* A list of non-parameter decls (notably enumeration constants)
 492      defined with the parameters.  */
 493   tree others;
 494   /* A compound expression of VLA sizes from the parameters, or NULL.
 495      In a function definition, these are used to ensure that
 496      side-effects in sizes of arrays converted to pointers (such as a
 497      parameter int i[n++]) take place; otherwise, they are
 498      ignored.  */
 499   tree pending_sizes;
 500   /* True when these arguments had [*].  */
 501   BOOL_BITFIELD had_vla_unspec : 1;
 502   /* True when the arguments are a (...) prototype.  */
 503   BOOL_BITFIELD no_named_args_stdarg_p : 1;
 504 };
 505
 506 /* A declarator.  */
 507 struct c_declarator {
 508   /* The kind of declarator.  */
 509   enum c_declarator_kind kind;
 510   location_t id_loc; /* Currently only set for cdk_id, cdk_array. */
 511   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
 512   struct c_declarator *declarator;
 513   union {
 514     /* For identifiers.  */
 515     struct {
 516       /* An IDENTIFIER_NODE, or NULL_TREE if an abstract
 517          declarator.  */
 518       tree id;
 519       /* Any attributes (which apply to the declaration rather than to
 520          the type described by the outer declarators).  */
 521       tree attrs;
 522     } id;
 523     /* For functions.  */
 524     struct c_arg_info *arg_info;
 525     /* For arrays.  */
 526     struct {
 527       /* The array dimension, or NULL for [] and [*].  */
 528       tree dimen;
 529       /* The qualifiers inside [].  */
 530       int quals;
 531       /* The attributes (currently ignored) inside [].  */
 532       tree attrs;
 533       /* Whether [static] was used.  */
 534       BOOL_BITFIELD static_p : 1;
 535       /* Whether [*] was used.  */
 536       BOOL_BITFIELD vla_unspec_p : 1;
 537     } array;
 538     /* For pointers, the qualifiers on the pointer type.  */
 539     int pointer_quals;
 540     /* For attributes.  */
 541     tree attrs;
 542   } u;
 543 };
 544
 545 /* A type name.  */
 546 struct c_type_name {
 547   /* The declaration specifiers.  */
 548   struct c_declspecs *specs;
 549   /* The declarator.  */
 550   struct c_declarator *declarator;
 551 };
 552
 553 /* A parameter.  */
 554 struct c_parm {
 555   /* The declaration specifiers, minus any prefix attributes.  */
 556   struct c_declspecs *specs;
 557   /* The attributes.  */
 558   tree attrs;
 559   /* The declarator.  */
 560   struct c_declarator *declarator;
 561   /* The location of the parameter.  */
 562   location_t loc;
 563 };
 564
 565 /* Used when parsing an enum.  Initialized by start_enum.  */
 566 struct c_enum_contents
 567 {
 568   /* While defining an enum type, this is 1 plus the last enumerator
 569      constant value.  */
 570   tree enum_next_value;
 571
 572   /* The enumeration type itself.  */
 573   tree enum_type;
 574
 575   /* Nonzero means that there was overflow computing enum_next_value.  */
 576   int enum_overflow;
 577 };
 578
 579 /* A type of reference to a static identifier in an inline
 580    function.  */
 581 enum c_inline_static_type {
 582   /* Identifier with internal linkage used in function that may be an
 583      inline definition (i.e., file-scope static).  */
 584   csi_internal,
 585   /* Modifiable object with static storage duration defined in
 586      function that may be an inline definition (i.e., local
 587      static).  */
 588   csi_modifiable
 589 };
 590
 591 \f
 592 /* in c-parser.cc */
 593 extern void c_parse_init (void);
 594 extern bool c_keyword_starts_typename (enum rid keyword);
 595
 596 /* in c-aux-info.cc */
 597 extern void gen_aux_info_record (tree, int, int, int);
 598
 599 /* in c-decl.cc */
 600 struct c_spot_bindings;
 601 class c_struct_parse_info;
 602 extern struct obstack parser_obstack;
 603 /* Set to IN_ITERATION_STMT if parsing an iteration-statement,
 604    to IN_OMP_BLOCK if parsing OpenMP structured block and
 605    IN_OMP_FOR if parsing OpenMP loop.  If parsing a switch statement,
 606    this is bitwise ORed with IN_SWITCH_STMT, unless parsing an
 607    iteration-statement, OpenMP block or loop within that switch.  */
 608 #define IN_SWITCH_STMT          1
 609 #define IN_ITERATION_STMT       2
 610 #define IN_OMP_BLOCK            4
 611 #define IN_OMP_FOR              8
 612 #define IN_OBJC_FOREACH         16
 613 extern unsigned char in_statement;
 614
 615 extern bool switch_statement_break_seen_p;
 616
 617 extern bool global_bindings_p (void);
 618 extern tree pushdecl (tree);
 619 extern unsigned int start_underspecified_init (location_t, tree);
 620 extern void finish_underspecified_init (tree, unsigned int);
 621 extern void push_scope (void);
 622 extern tree pop_scope (void);
 623 extern void c_bindings_start_stmt_expr (struct c_spot_bindings *);
 624 extern void c_bindings_end_stmt_expr (struct c_spot_bindings *);
 625
 626 extern void record_inline_static (location_t, tree, tree,
 627                                   enum c_inline_static_type);
 628 extern void c_init_decl_processing (void);
 629 extern void c_print_identifier (FILE *, tree, int);
 630 extern int quals_from_declspecs (const struct c_declspecs *);
 631 extern struct c_declarator *build_array_declarator (location_t, tree,
 632                                                     struct c_declspecs *,
 633                                                     bool, bool);
 634 extern tree build_enumerator (location_t, location_t, struct c_enum_contents *,
 635                               tree, tree);
 636 extern tree check_for_loop_decls (location_t, bool);
 637 extern void mark_forward_parm_decls (void);
 638 extern void declare_parm_level (void);
 639 extern void undeclared_variable (location_t, tree);
 640 extern tree lookup_label_for_goto (location_t, tree);
 641 extern tree declare_label (tree);
 642 extern tree define_label (location_t, tree);
 643 extern struct c_spot_bindings *c_get_switch_bindings (void);
 644 extern void c_release_switch_bindings (struct c_spot_bindings *);
 645 extern bool c_check_switch_jump_warnings (struct c_spot_bindings *,
 646                                           location_t, location_t);
 647 extern void finish_decl (tree, location_t, tree, tree, tree);
 648 extern tree finish_enum (tree, tree, tree);
 649 extern void finish_function (location_t = input_location);
 650 extern tree finish_struct (location_t, tree, tree, tree,
 651                            class c_struct_parse_info *);
 652 extern tree c_simulate_enum_decl (location_t, const char *,
 653                                   vec<string_int_pair> *);
 654 extern tree c_simulate_record_decl (location_t, const char *,
 655                                     array_slice<const tree>);
 656 extern struct c_arg_info *build_arg_info (void);
 657 extern struct c_arg_info *get_parm_info (bool, tree);
 658 extern tree grokfield (location_t, struct c_declarator *,
 659                        struct c_declspecs *, tree, tree *);
 660 extern tree groktypename (struct c_type_name *, tree *, bool *);
 661 extern tree grokparm (const struct c_parm *, tree *);
 662 extern tree implicitly_declare (location_t, tree);
 663 extern void keep_next_level (void);
 664 extern void pending_xref_error (void);
 665 extern void c_push_function_context (void);
 666 extern void c_pop_function_context (void);
 667 extern void push_parm_decl (const struct c_parm *, tree *);
 668 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
 669                                                         struct c_declarator *);
 670 extern tree c_builtin_function (tree);
 671 extern tree c_builtin_function_ext_scope (tree);
 672 extern tree c_simulate_builtin_function_decl (tree);
 673 extern void c_warn_unused_attributes (tree);
 674 extern tree c_warn_type_attributes (tree);
 675 extern void shadow_tag (const struct c_declspecs *);
 676 extern void shadow_tag_warned (const struct c_declspecs *, int);
 677 extern tree start_enum (location_t, struct c_enum_contents *, tree, tree);
 678 extern bool start_function (struct c_declspecs *, struct c_declarator *, tree);
 679 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
 680                         tree, bool = true, location_t * = NULL);
 681 extern tree start_struct (location_t, enum tree_code, tree,
 682                           class c_struct_parse_info **);
 683 extern void store_parm_decls (void);
 684 extern void store_parm_decls_from (struct c_arg_info *);
 685 extern void temp_store_parm_decls (tree, tree);
 686 extern void temp_pop_parm_decls (void);
 687 extern tree xref_tag (enum tree_code, tree);
 688 extern struct c_typespec parser_xref_tag (location_t, enum tree_code, tree,
 689                                           bool, tree, bool);
 690 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
 691                                     struct c_declarator *, location_t);
 692 extern struct c_declarator *build_attrs_declarator (tree,
 693                                                     struct c_declarator *);
 694 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
 695                                                        struct c_declarator *);
 696 extern struct c_declarator *build_id_declarator (tree);
 697 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
 698                                                      struct c_declarator *);
 699 extern struct c_declspecs *build_null_declspecs (void);
 700 extern struct c_declspecs *declspecs_add_qual (location_t,
 701                                                struct c_declspecs *, tree);
 702 extern struct c_declspecs *declspecs_add_type (location_t,
 703                                                struct c_declspecs *,
 704                                                struct c_typespec);
 705 extern struct c_declspecs *declspecs_add_scspec (location_t,
 706                                                  struct c_declspecs *, tree);
 707 extern struct c_declspecs *declspecs_add_attrs (location_t,
 708                                                 struct c_declspecs *, tree);
 709 extern struct c_declspecs *declspecs_add_addrspace (location_t,
 710                                                     struct c_declspecs *,
 711                                                     addr_space_t);
 712 extern struct c_declspecs *declspecs_add_alignas (location_t,
 713                                                   struct c_declspecs *, tree);
 714 extern struct c_declspecs *finish_declspecs (struct c_declspecs *);
 715
 716 /* in c-objc-common.cc */
 717 extern bool c_objc_common_init (void);
 718 extern bool c_missing_noreturn_ok_p (tree);
 719 extern bool c_warn_unused_global_decl (const_tree);
 720 extern void c_initialize_diagnostics (diagnostic_context *);
 721 extern bool c_var_mod_p (tree x, tree fn);
 722 extern alias_set_type c_get_alias_set (tree);
 723
 724 /* in c-typeck.cc */
 725 extern int in_alignof;
 726 extern int in_sizeof;
 727 extern int in_typeof;
 728 extern bool c_in_omp_for;
 729
 730 extern tree c_last_sizeof_arg;
 731 extern location_t c_last_sizeof_loc;
 732
 733 extern struct c_switch *c_switch_stack;
 734
 735 extern bool null_pointer_constant_p (const_tree);
 736
 737
 738 inline
 739 bool c_type_variably_modified_p (tree t)
 740 {
 741   return error_mark_node != t && C_TYPE_VARIABLY_MODIFIED (t);
 742 }
 743
 744
 745 extern bool char_type_p (tree);
 746 extern tree c_objc_common_truthvalue_conversion (location_t, tree);
 747 extern tree require_complete_type (location_t, tree);
 748 extern bool same_translation_unit_p (const_tree, const_tree);
 749 extern int comptypes (tree, tree);
 750 extern int comptypes_check_different_types (tree, tree, bool *);
 751 extern int comptypes_check_enum_int (tree, tree, bool *);
 752 extern bool c_mark_addressable (tree, bool = false);
 753 extern void c_incomplete_type_error (location_t, const_tree, const_tree);
 754 extern tree c_type_promotes_to (tree);
 755 extern struct c_expr default_function_array_conversion (location_t,
 756                                                         struct c_expr);
 757 extern struct c_expr default_function_array_read_conversion (location_t,
 758                                                              struct c_expr);
 759 extern struct c_expr convert_lvalue_to_rvalue (location_t, struct c_expr,
 760                                                bool, bool, bool = false);
 761 extern tree decl_constant_value_1 (tree, bool);
 762 extern void mark_exp_read (tree);
 763 extern tree composite_type (tree, tree);
 764 extern tree build_component_ref (location_t, tree, tree, location_t,
 765                                  location_t);
 766 extern tree build_array_ref (location_t, tree, tree);
 767 extern tree build_external_ref (location_t, tree, bool, tree *);
 768 extern void pop_maybe_used (bool);
 769 extern struct c_expr c_expr_sizeof_expr (location_t, struct c_expr);
 770 extern struct c_expr c_expr_sizeof_type (location_t, struct c_type_name *);
 771 extern struct c_expr parser_build_unary_op (location_t, enum tree_code,
 772                                             struct c_expr);
 773 extern struct c_expr parser_build_binary_op (location_t,
 774                                              enum tree_code, struct c_expr,
 775                                              struct c_expr);
 776 extern tree build_conditional_expr (location_t, tree, bool, tree, tree,
 777                                     location_t, tree, tree, location_t);
 778 extern tree build_compound_expr (location_t, tree, tree);
 779 extern tree c_cast_expr (location_t, struct c_type_name *, tree);
 780 extern tree build_c_cast (location_t, tree, tree);
 781 extern void store_init_value (location_t, tree, tree, tree);
 782 extern void maybe_warn_string_init (location_t, tree, struct c_expr);
 783 extern void start_init (tree, tree, bool, bool, rich_location *);
 784 extern void finish_init (void);
 785 extern void really_start_incremental_init (tree);
 786 extern void finish_implicit_inits (location_t, struct obstack *);
 787 extern void push_init_level (location_t, int, struct obstack *);
 788 extern struct c_expr pop_init_level (location_t, int, struct obstack *,
 789                                      location_t);
 790 extern void set_init_index (location_t, tree, tree, struct obstack *);
 791 extern void set_init_label (location_t, tree, location_t, struct obstack *);
 792 extern void process_init_element (location_t, struct c_expr, bool,
 793                                   struct obstack *);
 794 extern tree build_compound_literal (location_t, tree, tree, bool,
 795                                     unsigned int, struct c_declspecs *);
 796 extern void check_compound_literal_type (location_t, struct c_type_name *);
 797 extern tree c_start_switch (location_t, location_t, tree, bool);
 798 extern void c_finish_switch (tree, tree);
 799 extern tree build_asm_expr (location_t, tree, tree, tree, tree, tree, bool,
 800                             bool);
 801 extern tree build_asm_stmt (bool, tree);
 802 extern int c_types_compatible_p (tree, tree);
 803 extern tree c_begin_compound_stmt (bool);
 804 extern tree c_end_compound_stmt (location_t, tree, bool);
 805 extern void c_finish_if_stmt (location_t, tree, tree, tree);
 806 extern void c_finish_loop (location_t, location_t, tree, location_t, tree,
 807                            tree, tree, tree, bool);
 808 extern tree c_begin_stmt_expr (void);
 809 extern tree c_finish_stmt_expr (location_t, tree);
 810 extern tree c_process_expr_stmt (location_t, tree);
 811 extern tree c_finish_expr_stmt (location_t, tree);
 812 extern tree c_finish_return (location_t, tree, tree);
 813 extern tree c_finish_bc_stmt (location_t, tree, bool);
 814 extern tree c_finish_goto_label (location_t, tree);
 815 extern tree c_finish_goto_ptr (location_t, c_expr val);
 816 extern tree c_expr_to_decl (tree, bool *, bool *);
 817 extern tree c_finish_omp_construct (location_t, enum tree_code, tree, tree);
 818 extern tree c_finish_oacc_data (location_t, tree, tree);
 819 extern tree c_finish_oacc_host_data (location_t, tree, tree);
 820 extern tree c_begin_omp_parallel (void);
 821 extern tree c_finish_omp_parallel (location_t, tree, tree);
 822 extern tree c_begin_omp_task (void);
 823 extern tree c_finish_omp_task (location_t, tree, tree);
 824 extern void c_finish_omp_cancel (location_t, tree);
 825 extern void c_finish_omp_cancellation_point (location_t, tree);
 826 extern tree c_finish_omp_clauses (tree, enum c_omp_region_type);
 827 extern tree c_build_va_arg (location_t, tree, location_t, tree);
 828 extern tree c_finish_transaction (location_t, tree, int);
 829 extern bool c_tree_equal (tree, tree);
 830 extern tree c_build_function_call_vec (location_t, const vec<location_t>&,
 831                                        tree, vec<tree, va_gc> *,
 832                                        vec<tree, va_gc> *);
 833 extern tree c_omp_clause_copy_ctor (tree, tree, tree);
 834
 835 /* Set to 0 at beginning of a function definition, set to 1 if
 836    a return statement that specifies a return value is seen.  */
 837
 838 extern int current_function_returns_value;
 839
 840 /* Set to 0 at beginning of a function definition, set to 1 if
 841    a return statement with no argument is seen.  */
 842
 843 extern int current_function_returns_null;
 844
 845 /* Set to 0 at beginning of a function definition, set to 1 if
 846    a call to a noreturn function is seen.  */
 847
 848 extern int current_function_returns_abnormally;
 849
 850 /* In c-decl.cc */
 851
 852 /* Tell the binding oracle what kind of binding we are looking for.  */
 853
 854 enum c_oracle_request
 855 {
 856   C_ORACLE_SYMBOL,
 857   C_ORACLE_TAG,
 858   C_ORACLE_LABEL
 859 };
 860
 861 /* If this is non-NULL, then it is a "binding oracle" which can lazily
 862    create bindings when needed by the C compiler.  The oracle is told
 863    the name and type of the binding to create.  It can call pushdecl
 864    or the like to ensure the binding is visible; or do nothing,
 865    leaving the binding untouched.  c-decl.cc takes note of when the
 866    oracle has been called and will not call it again if it fails to
 867    create a given binding.  */
 868
 869 typedef void c_binding_oracle_function (enum c_oracle_request, tree identifier);
 870
 871 extern c_binding_oracle_function *c_binding_oracle;
 872
 873 extern void c_finish_incomplete_decl (tree);
 874 extern tree c_omp_reduction_id (enum tree_code, tree);
 875 extern tree c_omp_reduction_decl (tree);
 876 extern tree c_omp_reduction_lookup (tree, tree);
 877 extern tree c_check_omp_declare_reduction_r (tree *, int *, void *);
 878 extern bool c_check_in_current_scope (tree);
 879 extern void c_pushtag (location_t, tree, tree);
 880 extern void c_bind (location_t, tree, bool);
 881 extern bool tag_exists_p (enum tree_code, tree);
 882
 883 /* In c-errors.cc */
 884 extern bool pedwarn_c90 (location_t, int opt, const char *, ...)
 885     ATTRIBUTE_GCC_DIAG(3,4);
 886 extern bool pedwarn_c99 (location_t, int opt, const char *, ...)
 887     ATTRIBUTE_GCC_DIAG(3,4);
 888 extern bool pedwarn_c11 (location_t, int opt, const char *, ...)
 889     ATTRIBUTE_GCC_DIAG(3,4);
 890
 891 extern void
 892 set_c_expr_source_range (c_expr *expr,
 893                          location_t start, location_t finish);
 894
 895 extern void
 896 set_c_expr_source_range (c_expr *expr,
 897                          source_range src_range);
 898
 899 /* In c-fold.cc */
 900 extern vec<tree> incomplete_record_decls;
 901
 902 extern const char *c_get_sarif_source_language (const char *filename);
 903
 904 #if CHECKING_P
 905 namespace selftest {
 906   extern void run_c_tests (void);
 907 } // namespace selftest
 908 #endif /* #if CHECKING_P */
 909
 910
 911 #endif /* ! GCC_C_TREE_H */