xref: /netbsd-src/external/gpl3/gcc/dist/gcc/c/c-tree.h (revision b1e838363e3c6fc78a55519254d99869742dd33c)
1 /* Definitions for C parsing and type checking.
2    Copyright (C) 1987-2022 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 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, UNION_TYPE or ENUMERAL_TYPE, a list of
42    variable declarations whose type would be completed by completing
43    that type.  */
44 #define C_TYPE_INCOMPLETE_VARS(TYPE) \
45   TYPE_LANG_SLOT_1 (TREE_CHECK4 (TYPE, RECORD_TYPE, UNION_TYPE, \
46 				 QUAL_UNION_TYPE, ENUMERAL_TYPE))
47 
48 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
49    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword.  */
50 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
51 
52 /* Record whether a type or decl was written with nonconstant size.
53    Note that TYPE_SIZE may have simplified to a constant.  */
54 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
55 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
56 
57 /* Record whether a type is defined inside a struct or union type.
58    This is used for -Wc++-compat. */
59 #define C_TYPE_DEFINED_IN_STRUCT(TYPE) TYPE_LANG_FLAG_2 (TYPE)
60 
61 /* Record whether a typedef for type `int' was actually `signed int'.  */
62 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
63 
64 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
65    return type.  */
66 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
67 
68 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
69 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
70 
71 /* For a PARM_DECL, nonzero if it was declared as an array.  */
72 #define C_ARRAY_PARAMETER(NODE) DECL_LANG_FLAG_0 (NODE)
73 
74 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
75    been declared.  */
76 #define C_DECL_DECLARED_BUILTIN(EXP)		\
77   DECL_LANG_FLAG_3 (FUNCTION_DECL_CHECK (EXP))
78 
79 /* For FUNCTION_DECLs, evaluates true if the decl is built-in, has a
80    built-in prototype and does not have a non-built-in prototype.  */
81 #define C_DECL_BUILTIN_PROTOTYPE(EXP)		\
82   DECL_LANG_FLAG_6 (FUNCTION_DECL_CHECK (EXP))
83 
84 /* Record whether a decl was declared register.  This is strictly a
85    front-end flag, whereas DECL_REGISTER is used for code generation;
86    they may differ for structures with volatile fields.  */
87 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
88 
89 /* Record whether a decl was used in an expression anywhere except an
90    unevaluated operand of sizeof / typeof / alignof.  This is only
91    used for functions declared static but not defined, though outside
92    sizeof and typeof it is set for other function decls as well.  */
93 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (FUNCTION_DECL_CHECK (EXP))
94 
95 /* Record whether a variable has been declared threadprivate by
96    #pragma omp threadprivate.  */
97 #define C_DECL_THREADPRIVATE_P(DECL) DECL_LANG_FLAG_3 (VAR_DECL_CHECK (DECL))
98 
99 /* Set on VAR_DECLs for compound literals.  */
100 #define C_DECL_COMPOUND_LITERAL_P(DECL) \
101   DECL_LANG_FLAG_5 (VAR_DECL_CHECK (DECL))
102 
103 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
104    N.B. Could be simplified if all built-in decls had complete prototypes
105    (but this is presently difficult because some of them need FILE*).  */
106 #define C_DECL_ISNT_PROTOTYPE(EXP)			\
107        (EXP == 0					\
108 	|| (!prototype_p (TREE_TYPE (EXP))	\
109 	    && !fndecl_built_in_p (EXP)))
110 
111 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
112    TYPE_ARG_TYPES for functions with prototypes, but created for functions
113    without prototypes.  */
114 #define TYPE_ACTUAL_ARG_TYPES(NODE) \
115   TYPE_LANG_SLOT_1 (FUNCTION_TYPE_CHECK (NODE))
116 
117 /* For a CONSTRUCTOR, whether some initializer contains a
118    subexpression meaning it is not a constant expression.  */
119 #define CONSTRUCTOR_NON_CONST(EXPR) TREE_LANG_FLAG_1 (CONSTRUCTOR_CHECK (EXPR))
120 
121 /* For a SAVE_EXPR, nonzero if the operand of the SAVE_EXPR has already
122    been folded.  */
123 #define SAVE_EXPR_FOLDED_P(EXP)	TREE_LANG_FLAG_1 (SAVE_EXPR_CHECK (EXP))
124 
125 /* Record parser information about an expression that is irrelevant
126    for code generation alongside a tree representing its value.  */
127 struct c_expr
128 {
129   /* The value of the expression.  */
130   tree value;
131   /* Record the original unary/binary operator of an expression, which may
132      have been changed by fold, STRING_CST for unparenthesized string
133      constants, C_MAYBE_CONST_EXPR for __builtin_constant_p calls
134      (even if parenthesized), for subexpressions, and for non-constant
135      initializers, or ERROR_MARK for other expressions (including
136      parenthesized expressions).  */
137   enum tree_code original_code;
138   /* If not NULL, the original type of an expression.  This will
139      differ from the type of the value field for an enum constant.
140      The type of an enum constant is a plain integer type, but this
141      field will be the enum type.  */
142   tree original_type;
143 
144   /* The source range of this expression.  This is redundant
145      for node values that have locations, but not all node kinds
146      have locations (e.g. constants, and references to params, locals,
147      etc), so we stash a copy here.  */
148   source_range src_range;
149 
150   /* Access to the first and last locations within the source spelling
151      of this expression.  */
get_startc_expr152   location_t get_start () const { return src_range.m_start; }
get_finishc_expr153   location_t get_finish () const { return src_range.m_finish; }
154 
get_locationc_expr155   location_t get_location () const
156   {
157     if (EXPR_HAS_LOCATION (value))
158       return EXPR_LOCATION (value);
159     else
160       return make_location (get_start (), get_start (), get_finish ());
161   }
162 
163   /* Set the value to error_mark_node whilst ensuring that src_range
164      is initialized.  */
set_errorc_expr165   void set_error ()
166   {
167     value = error_mark_node;
168     src_range.m_start = UNKNOWN_LOCATION;
169     src_range.m_finish = UNKNOWN_LOCATION;
170   }
171 };
172 
173 /* Type alias for struct c_expr. This allows to use the structure
174    inside the VEC types.  */
175 typedef struct c_expr c_expr_t;
176 
177 /* A kind of type specifier.  Note that this information is currently
178    only used to distinguish tag definitions, tag references and typeof
179    uses.  */
180 enum c_typespec_kind {
181   /* No typespec.  This appears only in struct c_declspec.  */
182   ctsk_none,
183   /* A reserved keyword type specifier.  */
184   ctsk_resword,
185   /* A reference to a tag, previously declared, such as "struct foo".
186      This includes where the previous declaration was as a different
187      kind of tag, in which case this is only valid if shadowing that
188      tag in an inner scope.  */
189   ctsk_tagref,
190   /* Likewise, with standard attributes present in the reference.  */
191   ctsk_tagref_attrs,
192   /* A reference to a tag, not previously declared in a visible
193      scope.  */
194   ctsk_tagfirstref,
195   /* Likewise, with standard attributes present in the reference.  */
196   ctsk_tagfirstref_attrs,
197   /* A definition of a tag such as "struct foo { int a; }".  */
198   ctsk_tagdef,
199   /* A typedef name.  */
200   ctsk_typedef,
201   /* An ObjC-specific kind of type specifier.  */
202   ctsk_objc,
203   /* A typeof specifier, or _Atomic ( type-name ).  */
204   ctsk_typeof
205 };
206 
207 /* A type specifier: this structure is created in the parser and
208    passed to declspecs_add_type only.  */
209 struct c_typespec {
210   /* What kind of type specifier this is.  */
211   enum c_typespec_kind kind;
212   /* Whether the expression has operands suitable for use in constant
213      expressions.  */
214   bool expr_const_operands;
215   /* The specifier itself.  */
216   tree spec;
217   /* An expression to be evaluated before the type specifier, in the
218      case of typeof specifiers, or NULL otherwise or if no such
219      expression is required for a particular typeof specifier.  In
220      particular, when typeof is applied to an expression of variably
221      modified type, that expression must be evaluated in order to
222      determine array sizes that form part of the type, but the
223      expression itself (as opposed to the array sizes) forms no part
224      of the type and so needs to be recorded separately.  */
225   tree expr;
226 };
227 
228 /* A storage class specifier.  */
229 enum c_storage_class {
230   csc_none,
231   csc_auto,
232   csc_extern,
233   csc_register,
234   csc_static,
235   csc_typedef
236 };
237 
238 /* A type specifier keyword "void", "_Bool", "char", "int", "float",
239    "double", "_Decimal32", "_Decimal64", "_Decimal128", "_Fract", "_Accum",
240    or none of these.  */
241 enum c_typespec_keyword {
242   cts_none,
243   cts_void,
244   cts_bool,
245   cts_char,
246   cts_int,
247   cts_float,
248   cts_int_n,
249   cts_double,
250   cts_dfloat32,
251   cts_dfloat64,
252   cts_dfloat128,
253   cts_floatn_nx,
254   cts_fract,
255   cts_accum,
256   cts_auto_type
257 };
258 
259 /* This enum lists all the possible declarator specifiers, storage
260    class or attribute that a user can write.  There is at least one
261    enumerator per possible declarator specifier in the struct
262    c_declspecs below.
263 
264    It is used to index the array of declspec locations in struct
265    c_declspecs.  */
266 enum c_declspec_word {
267   cdw_typespec /* A catch-all for a typespec.  */,
268   cdw_storage_class  /* A catch-all for a storage class */,
269   cdw_attributes,
270   cdw_typedef,
271   cdw_explicit_signed,
272   cdw_deprecated,
273   cdw_default_int,
274   cdw_long,
275   cdw_long_long,
276   cdw_short,
277   cdw_signed,
278   cdw_unsigned,
279   cdw_complex,
280   cdw_inline,
281   cdw_noreturn,
282   cdw_thread,
283   cdw_const,
284   cdw_volatile,
285   cdw_restrict,
286   cdw_atomic,
287   cdw_saturating,
288   cdw_alignas,
289   cdw_address_space,
290   cdw_gimple,
291   cdw_rtl,
292   cdw_number_of_elements /* This one must always be the last
293 			    enumerator.  */
294 };
295 
296 enum c_declspec_il {
297   cdil_none,
298   cdil_gimple,		/* __GIMPLE  */
299   cdil_gimple_cfg,	/* __GIMPLE(cfg)  */
300   cdil_gimple_ssa,	/* __GIMPLE(ssa)  */
301   cdil_rtl		/* __RTL  */
302 };
303 
304 /* A sequence of declaration specifiers in C.  When a new declaration
305    specifier is added, please update the enum c_declspec_word above
306    accordingly.  */
307 struct c_declspecs {
308   location_t locations[cdw_number_of_elements];
309   /* The type specified, if a single type specifier such as a struct,
310      union or enum specifier, typedef name or typeof specifies the
311      whole type, or NULL_TREE if none or a keyword such as "void" or
312      "char" is used.  Does not include qualifiers.  */
313   tree type;
314   /* Any expression to be evaluated before the type, from a typeof
315      specifier.  */
316   tree expr;
317   /* The attributes from a typedef decl.  */
318   tree decl_attr;
319   /* When parsing, the GNU attributes and prefix standard attributes.
320      Outside the parser, this will be NULL; attributes (possibly from
321      multiple lists) will be passed separately.  */
322   tree attrs;
323   /* When parsing, postfix standard attributes (which appertain to the
324      type specified by the preceding declaration specifiers, unlike
325      prefix standard attributes which appertain to the declaration or
326      declarations as a whole).  */
327   tree postfix_attrs;
328   /* The pass to start compiling a __GIMPLE or __RTL function with.  */
329   char *gimple_or_rtl_pass;
330   /* ENTRY BB count.  */
331   profile_count entry_bb_count;
332   /* The base-2 log of the greatest alignment required by an _Alignas
333      specifier, in bytes, or -1 if no such specifiers with nonzero
334      alignment.  */
335   int align_log;
336   /* For the __intN declspec, this stores the index into the int_n_* arrays.  */
337   int int_n_idx;
338   /* For the _FloatN and _FloatNx declspec, this stores the index into
339      the floatn_nx_types array.  */
340   int floatn_nx_idx;
341   /* The storage class specifier, or csc_none if none.  */
342   enum c_storage_class storage_class;
343   /* Any type specifier keyword used such as "int", not reflecting
344      modifiers such as "short", or cts_none if none.  */
345   ENUM_BITFIELD (c_typespec_keyword) typespec_word : 8;
346   /* The kind of type specifier if one has been seen, ctsk_none
347      otherwise.  */
348   ENUM_BITFIELD (c_typespec_kind) typespec_kind : 4;
349   ENUM_BITFIELD (c_declspec_il) declspec_il : 3;
350   /* Whether any expressions in typeof specifiers may appear in
351      constant expressions.  */
352   BOOL_BITFIELD expr_const_operands : 1;
353   /* Whether any declaration specifiers have been seen at all.  */
354   BOOL_BITFIELD declspecs_seen_p : 1;
355   /* Whether any declaration specifiers other than standard attributes
356      have been seen at all.  If only standard attributes have been
357      seen, this is an attribute-declaration.  */
358   BOOL_BITFIELD non_std_attrs_seen_p : 1;
359   /* Whether something other than a storage class specifier or
360      attribute has been seen.  This is used to warn for the
361      obsolescent usage of storage class specifiers other than at the
362      start of the list.  (Doing this properly would require function
363      specifiers to be handled separately from storage class
364      specifiers.)  */
365   BOOL_BITFIELD non_sc_seen_p : 1;
366   /* Whether the type is specified by a typedef or typeof name.  */
367   BOOL_BITFIELD typedef_p : 1;
368   /* Whether the type is explicitly "signed" or specified by a typedef
369      whose type is explicitly "signed".  */
370   BOOL_BITFIELD explicit_signed_p : 1;
371   /* Whether the specifiers include a deprecated typedef.  */
372   BOOL_BITFIELD deprecated_p : 1;
373   /* Whether the specifiers include an unavailable typedef.  */
374   BOOL_BITFIELD unavailable_p : 1;
375   /* Whether the type defaulted to "int" because there were no type
376      specifiers.  */
377   BOOL_BITFIELD default_int_p : 1;
378   /* Whether "long" was specified.  */
379   BOOL_BITFIELD long_p : 1;
380   /* Whether "long" was specified more than once.  */
381   BOOL_BITFIELD long_long_p : 1;
382   /* Whether "short" was specified.  */
383   BOOL_BITFIELD short_p : 1;
384   /* Whether "signed" was specified.  */
385   BOOL_BITFIELD signed_p : 1;
386   /* Whether "unsigned" was specified.  */
387   BOOL_BITFIELD unsigned_p : 1;
388   /* Whether "complex" was specified.  */
389   BOOL_BITFIELD complex_p : 1;
390   /* Whether "inline" was specified.  */
391   BOOL_BITFIELD inline_p : 1;
392   /* Whether "_Noreturn" was speciied.  */
393   BOOL_BITFIELD noreturn_p : 1;
394   /* Whether "__thread" or "_Thread_local" was specified.  */
395   BOOL_BITFIELD thread_p : 1;
396   /* Whether "__thread" rather than "_Thread_local" was specified.  */
397   BOOL_BITFIELD thread_gnu_p : 1;
398   /* Whether "const" was specified.  */
399   BOOL_BITFIELD const_p : 1;
400   /* Whether "volatile" was specified.  */
401   BOOL_BITFIELD volatile_p : 1;
402   /* Whether "restrict" was specified.  */
403   BOOL_BITFIELD restrict_p : 1;
404   /* Whether "_Atomic" was specified.  */
405   BOOL_BITFIELD atomic_p : 1;
406   /* Whether "_Sat" was specified.  */
407   BOOL_BITFIELD saturating_p : 1;
408   /* Whether any alignment specifier (even with zero alignment) was
409      specified.  */
410   BOOL_BITFIELD alignas_p : 1;
411   /* The address space that the declaration belongs to.  */
412   addr_space_t address_space;
413 };
414 
415 /* The various kinds of declarators in C.  */
416 enum c_declarator_kind {
417   /* An identifier.  */
418   cdk_id,
419   /* A function.  */
420   cdk_function,
421   /* An array.  */
422   cdk_array,
423   /* A pointer.  */
424   cdk_pointer,
425   /* Parenthesized declarator with nested attributes.  */
426   cdk_attrs
427 };
428 
429 struct c_arg_tag {
430   /* The argument name.  */
431   tree id;
432   /* The type of the argument.  */
433   tree type;
434 };
435 
436 
437 /* Information about the parameters in a function declarator.  */
438 struct c_arg_info {
439   /* A list of parameter decls.  */
440   tree parms;
441   /* A list of structure, union and enum tags defined.  */
442   vec<c_arg_tag, va_gc> *tags;
443   /* A list of argument types to go in the FUNCTION_TYPE.  */
444   tree types;
445   /* A list of non-parameter decls (notably enumeration constants)
446      defined with the parameters.  */
447   tree others;
448   /* A compound expression of VLA sizes from the parameters, or NULL.
449      In a function definition, these are used to ensure that
450      side-effects in sizes of arrays converted to pointers (such as a
451      parameter int i[n++]) take place; otherwise, they are
452      ignored.  */
453   tree pending_sizes;
454   /* True when these arguments had [*].  */
455   BOOL_BITFIELD had_vla_unspec : 1;
456 };
457 
458 /* A declarator.  */
459 struct c_declarator {
460   /* The kind of declarator.  */
461   enum c_declarator_kind kind;
462   location_t id_loc; /* Currently only set for cdk_id, cdk_array. */
463   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
464   struct c_declarator *declarator;
465   union {
466     /* For identifiers.  */
467     struct {
468       /* An IDENTIFIER_NODE, or NULL_TREE if an abstract
469 	 declarator.  */
470       tree id;
471       /* Any attributes (which apply to the declaration rather than to
472 	 the type described by the outer declarators).  */
473       tree attrs;
474     } id;
475     /* For functions.  */
476     struct c_arg_info *arg_info;
477     /* For arrays.  */
478     struct {
479       /* The array dimension, or NULL for [] and [*].  */
480       tree dimen;
481       /* The qualifiers inside [].  */
482       int quals;
483       /* The attributes (currently ignored) inside [].  */
484       tree attrs;
485       /* Whether [static] was used.  */
486       BOOL_BITFIELD static_p : 1;
487       /* Whether [*] was used.  */
488       BOOL_BITFIELD vla_unspec_p : 1;
489     } array;
490     /* For pointers, the qualifiers on the pointer type.  */
491     int pointer_quals;
492     /* For attributes.  */
493     tree attrs;
494   } u;
495 };
496 
497 /* A type name.  */
498 struct c_type_name {
499   /* The declaration specifiers.  */
500   struct c_declspecs *specs;
501   /* The declarator.  */
502   struct c_declarator *declarator;
503 };
504 
505 /* A parameter.  */
506 struct c_parm {
507   /* The declaration specifiers, minus any prefix attributes.  */
508   struct c_declspecs *specs;
509   /* The attributes.  */
510   tree attrs;
511   /* The declarator.  */
512   struct c_declarator *declarator;
513   /* The location of the parameter.  */
514   location_t loc;
515 };
516 
517 /* Used when parsing an enum.  Initialized by start_enum.  */
518 struct c_enum_contents
519 {
520   /* While defining an enum type, this is 1 plus the last enumerator
521      constant value.  */
522   tree enum_next_value;
523 
524   /* Nonzero means that there was overflow computing enum_next_value.  */
525   int enum_overflow;
526 };
527 
528 /* A type of reference to a static identifier in an inline
529    function.  */
530 enum c_inline_static_type {
531   /* Identifier with internal linkage used in function that may be an
532      inline definition (i.e., file-scope static).  */
533   csi_internal,
534   /* Modifiable object with static storage duration defined in
535      function that may be an inline definition (i.e., local
536      static).  */
537   csi_modifiable
538 };
539 
540 
541 /* in c-parser.cc */
542 extern void c_parse_init (void);
543 extern bool c_keyword_starts_typename (enum rid keyword);
544 
545 /* in c-aux-info.cc */
546 extern void gen_aux_info_record (tree, int, int, int);
547 
548 /* in c-decl.cc */
549 struct c_spot_bindings;
550 class c_struct_parse_info;
551 extern struct obstack parser_obstack;
552 /* Set to IN_ITERATION_STMT if parsing an iteration-statement,
553    to IN_OMP_BLOCK if parsing OpenMP structured block and
554    IN_OMP_FOR if parsing OpenMP loop.  If parsing a switch statement,
555    this is bitwise ORed with IN_SWITCH_STMT, unless parsing an
556    iteration-statement, OpenMP block or loop within that switch.  */
557 #define IN_SWITCH_STMT		1
558 #define IN_ITERATION_STMT	2
559 #define IN_OMP_BLOCK		4
560 #define IN_OMP_FOR		8
561 #define IN_OBJC_FOREACH		16
562 extern unsigned char in_statement;
563 
564 extern bool switch_statement_break_seen_p;
565 
566 extern bool global_bindings_p (void);
567 extern tree pushdecl (tree);
568 extern void push_scope (void);
569 extern tree pop_scope (void);
570 extern void c_bindings_start_stmt_expr (struct c_spot_bindings *);
571 extern void c_bindings_end_stmt_expr (struct c_spot_bindings *);
572 
573 extern void record_inline_static (location_t, tree, tree,
574 				  enum c_inline_static_type);
575 extern void c_init_decl_processing (void);
576 extern void c_print_identifier (FILE *, tree, int);
577 extern int quals_from_declspecs (const struct c_declspecs *);
578 extern struct c_declarator *build_array_declarator (location_t, tree,
579     						    struct c_declspecs *,
580 						    bool, bool);
581 extern tree build_enumerator (location_t, location_t, struct c_enum_contents *,
582 			      tree, tree);
583 extern tree check_for_loop_decls (location_t, bool);
584 extern void mark_forward_parm_decls (void);
585 extern void declare_parm_level (void);
586 extern void undeclared_variable (location_t, tree);
587 extern tree lookup_label_for_goto (location_t, tree);
588 extern tree declare_label (tree);
589 extern tree define_label (location_t, tree);
590 extern struct c_spot_bindings *c_get_switch_bindings (void);
591 extern void c_release_switch_bindings (struct c_spot_bindings *);
592 extern bool c_check_switch_jump_warnings (struct c_spot_bindings *,
593 					  location_t, location_t);
594 extern void finish_decl (tree, location_t, tree, tree, tree);
595 extern tree finish_enum (tree, tree, tree);
596 extern void finish_function (location_t = input_location);
597 extern tree finish_struct (location_t, tree, tree, tree,
598 			   class c_struct_parse_info *);
599 extern tree c_simulate_enum_decl (location_t, const char *,
600 				  vec<string_int_pair> *);
601 extern tree c_simulate_record_decl (location_t, const char *,
602 				    array_slice<const tree>);
603 extern struct c_arg_info *build_arg_info (void);
604 extern struct c_arg_info *get_parm_info (bool, tree);
605 extern tree grokfield (location_t, struct c_declarator *,
606 		       struct c_declspecs *, tree, tree *);
607 extern tree groktypename (struct c_type_name *, tree *, bool *);
608 extern tree grokparm (const struct c_parm *, tree *);
609 extern tree implicitly_declare (location_t, tree);
610 extern void keep_next_level (void);
611 extern void pending_xref_error (void);
612 extern void c_push_function_context (void);
613 extern void c_pop_function_context (void);
614 extern void push_parm_decl (const struct c_parm *, tree *);
615 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
616 							struct c_declarator *);
617 extern tree c_builtin_function (tree);
618 extern tree c_builtin_function_ext_scope (tree);
619 extern tree c_simulate_builtin_function_decl (tree);
620 extern void c_warn_unused_attributes (tree);
621 extern tree c_warn_type_attributes (tree);
622 extern void shadow_tag (const struct c_declspecs *);
623 extern void shadow_tag_warned (const struct c_declspecs *, int);
624 extern tree start_enum (location_t, struct c_enum_contents *, tree);
625 extern bool start_function (struct c_declspecs *, struct c_declarator *, tree);
626 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
627 			tree, location_t * = NULL);
628 extern tree start_struct (location_t, enum tree_code, tree,
629 			  class c_struct_parse_info **);
630 extern void store_parm_decls (void);
631 extern void store_parm_decls_from (struct c_arg_info *);
632 extern void temp_store_parm_decls (tree, tree);
633 extern void temp_pop_parm_decls (void);
634 extern tree xref_tag (enum tree_code, tree);
635 extern struct c_typespec parser_xref_tag (location_t, enum tree_code, tree,
636 					  bool, tree);
637 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
638 				    struct c_declarator *, location_t);
639 extern struct c_declarator *build_attrs_declarator (tree,
640 						    struct c_declarator *);
641 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
642 						       struct c_declarator *);
643 extern struct c_declarator *build_id_declarator (tree);
644 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
645 						     struct c_declarator *);
646 extern struct c_declspecs *build_null_declspecs (void);
647 extern struct c_declspecs *declspecs_add_qual (location_t,
648 					       struct c_declspecs *, tree);
649 extern struct c_declspecs *declspecs_add_type (location_t,
650 					       struct c_declspecs *,
651 					       struct c_typespec);
652 extern struct c_declspecs *declspecs_add_scspec (location_t,
653 						 struct c_declspecs *, tree);
654 extern struct c_declspecs *declspecs_add_attrs (location_t,
655 						struct c_declspecs *, tree);
656 extern struct c_declspecs *declspecs_add_addrspace (location_t,
657 						    struct c_declspecs *,
658 						    addr_space_t);
659 extern struct c_declspecs *declspecs_add_alignas (location_t,
660 						  struct c_declspecs *, tree);
661 extern struct c_declspecs *finish_declspecs (struct c_declspecs *);
662 
663 /* in c-objc-common.cc */
664 extern bool c_objc_common_init (void);
665 extern bool c_missing_noreturn_ok_p (tree);
666 extern bool c_warn_unused_global_decl (const_tree);
667 extern void c_initialize_diagnostics (diagnostic_context *);
668 extern bool c_vla_unspec_p (tree x, tree fn);
669 extern alias_set_type c_get_alias_set (tree);
670 
671 /* in c-typeck.cc */
672 extern int in_alignof;
673 extern int in_sizeof;
674 extern int in_typeof;
675 extern bool c_in_omp_for;
676 
677 extern tree c_last_sizeof_arg;
678 extern location_t c_last_sizeof_loc;
679 
680 extern struct c_switch *c_switch_stack;
681 
682 extern bool char_type_p (tree);
683 extern tree c_objc_common_truthvalue_conversion (location_t, tree);
684 extern tree require_complete_type (location_t, tree);
685 extern bool same_translation_unit_p (const_tree, const_tree);
686 extern int comptypes (tree, tree);
687 extern int comptypes_check_different_types (tree, tree, bool *);
688 extern bool c_vla_type_p (const_tree);
689 extern bool c_mark_addressable (tree, bool = false);
690 extern void c_incomplete_type_error (location_t, const_tree, const_tree);
691 extern tree c_type_promotes_to (tree);
692 extern struct c_expr default_function_array_conversion (location_t,
693 							struct c_expr);
694 extern struct c_expr default_function_array_read_conversion (location_t,
695 							     struct c_expr);
696 extern struct c_expr convert_lvalue_to_rvalue (location_t, struct c_expr,
697 					       bool, bool);
698 extern tree decl_constant_value_1 (tree, bool);
699 extern void mark_exp_read (tree);
700 extern tree composite_type (tree, tree);
701 extern tree build_component_ref (location_t, tree, tree, location_t);
702 extern tree build_array_ref (location_t, tree, tree);
703 extern tree build_external_ref (location_t, tree, bool, tree *);
704 extern void pop_maybe_used (bool);
705 extern struct c_expr c_expr_sizeof_expr (location_t, struct c_expr);
706 extern struct c_expr c_expr_sizeof_type (location_t, struct c_type_name *);
707 extern struct c_expr parser_build_unary_op (location_t, enum tree_code,
708     					    struct c_expr);
709 extern struct c_expr parser_build_binary_op (location_t,
710     					     enum tree_code, struct c_expr,
711 					     struct c_expr);
712 extern tree build_conditional_expr (location_t, tree, bool, tree, tree,
713 				    location_t, tree, tree, location_t);
714 extern tree build_compound_expr (location_t, tree, tree);
715 extern tree c_cast_expr (location_t, struct c_type_name *, tree);
716 extern tree build_c_cast (location_t, tree, tree);
717 extern void store_init_value (location_t, tree, tree, tree);
718 extern void maybe_warn_string_init (location_t, tree, struct c_expr);
719 extern void start_init (tree, tree, int, rich_location *);
720 extern void finish_init (void);
721 extern void really_start_incremental_init (tree);
722 extern void finish_implicit_inits (location_t, struct obstack *);
723 extern void push_init_level (location_t, int, struct obstack *);
724 extern struct c_expr pop_init_level (location_t, int, struct obstack *,
725 				     location_t);
726 extern void set_init_index (location_t, tree, tree, struct obstack *);
727 extern void set_init_label (location_t, tree, location_t, struct obstack *);
728 extern void process_init_element (location_t, struct c_expr, bool,
729 				  struct obstack *);
730 extern tree build_compound_literal (location_t, tree, tree, bool,
731 				    unsigned int);
732 extern void check_compound_literal_type (location_t, struct c_type_name *);
733 extern tree c_start_switch (location_t, location_t, tree, bool);
734 extern void c_finish_switch (tree, tree);
735 extern tree build_asm_expr (location_t, tree, tree, tree, tree, tree, bool,
736 			    bool);
737 extern tree build_asm_stmt (bool, tree);
738 extern int c_types_compatible_p (tree, tree);
739 extern tree c_begin_compound_stmt (bool);
740 extern tree c_end_compound_stmt (location_t, tree, bool);
741 extern void c_finish_if_stmt (location_t, tree, tree, tree);
742 extern void c_finish_loop (location_t, location_t, tree, location_t, tree,
743 			   tree, tree, tree, bool);
744 extern tree c_begin_stmt_expr (void);
745 extern tree c_finish_stmt_expr (location_t, tree);
746 extern tree c_process_expr_stmt (location_t, tree);
747 extern tree c_finish_expr_stmt (location_t, tree);
748 extern tree c_finish_return (location_t, tree, tree);
749 extern tree c_finish_bc_stmt (location_t, tree, bool);
750 extern tree c_finish_goto_label (location_t, tree);
751 extern tree c_finish_goto_ptr (location_t, c_expr val);
752 extern tree c_expr_to_decl (tree, bool *, bool *);
753 extern tree c_finish_omp_construct (location_t, enum tree_code, tree, tree);
754 extern tree c_finish_oacc_data (location_t, tree, tree);
755 extern tree c_finish_oacc_host_data (location_t, tree, tree);
756 extern tree c_begin_omp_parallel (void);
757 extern tree c_finish_omp_parallel (location_t, tree, tree);
758 extern tree c_begin_omp_task (void);
759 extern tree c_finish_omp_task (location_t, tree, tree);
760 extern void c_finish_omp_cancel (location_t, tree);
761 extern void c_finish_omp_cancellation_point (location_t, tree);
762 extern tree c_finish_omp_clauses (tree, enum c_omp_region_type);
763 extern tree c_build_va_arg (location_t, tree, location_t, tree);
764 extern tree c_finish_transaction (location_t, tree, int);
765 extern bool c_tree_equal (tree, tree);
766 extern tree c_build_function_call_vec (location_t, const vec<location_t>&,
767 				       tree, vec<tree, va_gc> *,
768 				       vec<tree, va_gc> *);
769 extern tree c_omp_clause_copy_ctor (tree, tree, tree);
770 
771 /* Set to 0 at beginning of a function definition, set to 1 if
772    a return statement that specifies a return value is seen.  */
773 
774 extern int current_function_returns_value;
775 
776 /* Set to 0 at beginning of a function definition, set to 1 if
777    a return statement with no argument is seen.  */
778 
779 extern int current_function_returns_null;
780 
781 /* Set to 0 at beginning of a function definition, set to 1 if
782    a call to a noreturn function is seen.  */
783 
784 extern int current_function_returns_abnormally;
785 
786 /* In c-decl.cc */
787 
788 /* Tell the binding oracle what kind of binding we are looking for.  */
789 
790 enum c_oracle_request
791 {
792   C_ORACLE_SYMBOL,
793   C_ORACLE_TAG,
794   C_ORACLE_LABEL
795 };
796 
797 /* If this is non-NULL, then it is a "binding oracle" which can lazily
798    create bindings when needed by the C compiler.  The oracle is told
799    the name and type of the binding to create.  It can call pushdecl
800    or the like to ensure the binding is visible; or do nothing,
801    leaving the binding untouched.  c-decl.cc takes note of when the
802    oracle has been called and will not call it again if it fails to
803    create a given binding.  */
804 
805 typedef void c_binding_oracle_function (enum c_oracle_request, tree identifier);
806 
807 extern c_binding_oracle_function *c_binding_oracle;
808 
809 extern void c_finish_incomplete_decl (tree);
810 extern tree c_omp_reduction_id (enum tree_code, tree);
811 extern tree c_omp_reduction_decl (tree);
812 extern tree c_omp_reduction_lookup (tree, tree);
813 extern tree c_check_omp_declare_reduction_r (tree *, int *, void *);
814 extern bool c_check_in_current_scope (tree);
815 extern void c_pushtag (location_t, tree, tree);
816 extern void c_bind (location_t, tree, bool);
817 extern bool tag_exists_p (enum tree_code, tree);
818 
819 /* In c-errors.cc */
820 extern bool pedwarn_c90 (location_t, int opt, const char *, ...)
821     ATTRIBUTE_GCC_DIAG(3,4);
822 extern bool pedwarn_c99 (location_t, int opt, const char *, ...)
823     ATTRIBUTE_GCC_DIAG(3,4);
824 extern bool pedwarn_c11 (location_t, int opt, const char *, ...)
825     ATTRIBUTE_GCC_DIAG(3,4);
826 
827 extern void
828 set_c_expr_source_range (c_expr *expr,
829 			 location_t start, location_t finish);
830 
831 extern void
832 set_c_expr_source_range (c_expr *expr,
833 			 source_range src_range);
834 
835 /* In c-fold.cc */
836 extern vec<tree> incomplete_record_decls;
837 
838 #if CHECKING_P
839 namespace selftest {
840   extern void run_c_tests (void);
841 } // namespace selftest
842 #endif /* #if CHECKING_P */
843 
844 
845 #endif /* ! GCC_C_TREE_H */
846