re PR c/20519 (completed type not selected properly with typeof)
[gcc.git] / gcc / c-tree.h
1 /* Definitions for C parsing and type checking.
2 Copyright (C) 1987, 1993, 1994, 1995, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
21
22 #ifndef GCC_C_TREE_H
23 #define GCC_C_TREE_H
24
25 #include "c-common.h"
26 #include "diagnostic.h"
27
28 /* struct lang_identifier is private to c-decl.c, but langhooks.c needs to
29 know how big it is. This is sanity-checked in c-decl.c. */
30 #define C_SIZEOF_STRUCT_LANG_IDENTIFIER \
31 (sizeof (struct c_common_identifier) + 3 * sizeof (void *))
32
33 /* For gc purposes, return the most likely link for the longest chain. */
34 #define C_LANG_TREE_NODE_CHAIN_NEXT(T) \
35 ((union lang_tree_node *) \
36 (TREE_CODE (T) == INTEGER_TYPE ? TYPE_NEXT_VARIANT (T) \
37 : TREE_CODE (T) == COMPOUND_EXPR ? TREE_OPERAND (T, 1) \
38 : TREE_CHAIN (T)))
39
40 /* Language-specific declaration information. */
41
42 struct lang_decl GTY(())
43 {
44 char dummy;
45 };
46
47 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only. */
48 #define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1 (TYPE)
49
50 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile. */
51 #define C_TYPE_FIELDS_VOLATILE(TYPE) TREE_LANG_FLAG_2 (TYPE)
52
53 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
54 nonzero if the definition of the type has already started. */
55 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
56
57 /* In an incomplete RECORD_TYPE or UNION_TYPE, a list of variable
58 declarations whose type would be completed by completing that type. */
59 #define C_TYPE_INCOMPLETE_VARS(TYPE) TYPE_VFIELD (TYPE)
60
61 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
62 keyword. C_RID_CODE (node) is then the RID_* value of the keyword,
63 and C_RID_YYCODE is the token number wanted by Yacc. */
64 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
65
66 struct lang_type GTY(())
67 {
68 /* In a RECORD_TYPE, a sorted array of the fields of the type. */
69 struct sorted_fields_type * GTY ((reorder ("resort_sorted_fields"))) s;
70 /* In an ENUMERAL_TYPE, the min and max values. */
71 tree enum_min;
72 tree enum_max;
73 /* In a RECORD_TYPE, information specific to Objective-C, such
74 as a list of adopted protocols or a pointer to a corresponding
75 @interface. See objc/objc-act.h for details. */
76 tree objc_info;
77 };
78
79 /* Record whether a type or decl was written with nonconstant size.
80 Note that TYPE_SIZE may have simplified to a constant. */
81 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
82 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
83
84 /* Record whether a typedef for type `int' was actually `signed int'. */
85 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
86
87 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
88 return type. */
89 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
90
91 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration. */
92 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
93
94 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
95 been declared. */
96 #define C_DECL_DECLARED_BUILTIN(EXP) DECL_LANG_FLAG_3 (EXP)
97
98 /* Record whether a decl was declared register. This is strictly a
99 front-end flag, whereas DECL_REGISTER is used for code generation;
100 they may differ for structures with volatile fields. */
101 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
102
103 /* Record whether a decl was used in an expression anywhere except an
104 unevaluated operand of sizeof / typeof / alignof. This is only
105 used for functions declared static but not defined, though outside
106 sizeof and typeof it is set for other function decls as well. */
107 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (EXP)
108
109 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
110 N.B. Could be simplified if all built-in decls had complete prototypes
111 (but this is presently difficult because some of them need FILE*). */
112 #define C_DECL_ISNT_PROTOTYPE(EXP) \
113 (EXP == 0 \
114 || (TYPE_ARG_TYPES (TREE_TYPE (EXP)) == 0 \
115 && !DECL_BUILT_IN (EXP)))
116
117 /* For FUNCTION_TYPE, a hidden list of types of arguments. The same as
118 TYPE_ARG_TYPES for functions with prototypes, but created for functions
119 without prototypes. */
120 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_LANG_SLOT_1 (NODE)
121
122 /* Record parser information about an expression that is irrelevant
123 for code generation alongside a tree representing its value. */
124 struct c_expr
125 {
126 /* The value of the expression. */
127 tree value;
128 /* Record the original binary operator of an expression, which may
129 have been changed by fold, STRING_CST for unparenthesized string
130 constants, or ERROR_MARK for other expressions (including
131 parenthesized expressions). */
132 enum tree_code original_code;
133 };
134
135 /* A kind of type specifier. Note that this information is currently
136 only used to distinguish tag definitions, tag references and typeof
137 uses. */
138 enum c_typespec_kind {
139 /* A reserved keyword type specifier. */
140 ctsk_resword,
141 /* A reference to a tag, previously declared, such as "struct foo".
142 This includes where the previous declaration was as a different
143 kind of tag, in which case this is only valid if shadowing that
144 tag in an inner scope. */
145 ctsk_tagref,
146 /* A reference to a tag, not previously declared in a visible
147 scope. */
148 ctsk_tagfirstref,
149 /* A definition of a tag such as "struct foo { int a; }". */
150 ctsk_tagdef,
151 /* A typedef name. */
152 ctsk_typedef,
153 /* An ObjC-specific kind of type specifier. */
154 ctsk_objc,
155 /* A typeof specifier. */
156 ctsk_typeof
157 };
158
159 /* A type specifier: this structure is created in the parser and
160 passed to declspecs_add_type only. */
161 struct c_typespec {
162 /* What kind of type specifier this is. */
163 enum c_typespec_kind kind;
164 /* The specifier itself. */
165 tree spec;
166 };
167
168 /* A storage class specifier. */
169 enum c_storage_class {
170 csc_none,
171 csc_auto,
172 csc_extern,
173 csc_register,
174 csc_static,
175 csc_typedef
176 };
177
178 /* A type specifier keyword "void", "_Bool", "char", "int", "float",
179 "double", or none of these. */
180 enum c_typespec_keyword {
181 cts_none,
182 cts_void,
183 cts_bool,
184 cts_char,
185 cts_int,
186 cts_float,
187 cts_double
188 };
189
190 /* A sequence of declaration specifiers in C. */
191 struct c_declspecs {
192 /* The type specified, if a single type specifier such as a struct,
193 union or enum specifier, typedef name or typeof specifies the
194 whole type, or NULL_TREE if none or a keyword such as "void" or
195 "char" is used. Does not include qualifiers. */
196 tree type;
197 /* The attributes from a typedef decl. */
198 tree decl_attr;
199 /* When parsing, the attributes. Outside the parser, this will be
200 NULL; attributes (possibly from multiple lists) will be passed
201 separately. */
202 tree attrs;
203 /* Any type specifier keyword used such as "int", not reflecting
204 modifiers such as "short", or cts_none if none. */
205 enum c_typespec_keyword typespec_word;
206 /* The storage class specifier, or csc_none if none. */
207 enum c_storage_class storage_class;
208 /* Whether any declaration specifiers have been seen at all. */
209 BOOL_BITFIELD declspecs_seen_p : 1;
210 /* Whether a type specifier has been seen. */
211 BOOL_BITFIELD type_seen_p : 1;
212 /* Whether something other than a storage class specifier or
213 attribute has been seen. This is used to warn for the
214 obsolescent usage of storage class specifiers other than at the
215 start of the list. (Doing this properly would require function
216 specifiers to be handled separately from storage class
217 specifiers.) */
218 BOOL_BITFIELD non_sc_seen_p : 1;
219 /* Whether the type is specified by a typedef or typeof name. */
220 BOOL_BITFIELD typedef_p : 1;
221 /* Whether a struct, union or enum type either had its content
222 defined by a type specifier in the list or was the first visible
223 declaration of its tag. */
224 BOOL_BITFIELD tag_defined_p : 1;
225 /* Whether the type is explicitly "signed" or specified by a typedef
226 whose type is explicitly "signed". */
227 BOOL_BITFIELD explicit_signed_p : 1;
228 /* Whether the specifiers include a deprecated typedef. */
229 BOOL_BITFIELD deprecated_p : 1;
230 /* Whether the type defaulted to "int" because there were no type
231 specifiers. */
232 BOOL_BITFIELD default_int_p;
233 /* Whether "long" was specified. */
234 BOOL_BITFIELD long_p : 1;
235 /* Whether "long" was specified more than once. */
236 BOOL_BITFIELD long_long_p : 1;
237 /* Whether "short" was specified. */
238 BOOL_BITFIELD short_p : 1;
239 /* Whether "signed" was specified. */
240 BOOL_BITFIELD signed_p : 1;
241 /* Whether "unsigned" was specified. */
242 BOOL_BITFIELD unsigned_p : 1;
243 /* Whether "complex" was specified. */
244 BOOL_BITFIELD complex_p : 1;
245 /* Whether "inline" was specified. */
246 BOOL_BITFIELD inline_p : 1;
247 /* Whether "__thread" was specified. */
248 BOOL_BITFIELD thread_p : 1;
249 /* Whether "const" was specified. */
250 BOOL_BITFIELD const_p : 1;
251 /* Whether "volatile" was specified. */
252 BOOL_BITFIELD volatile_p : 1;
253 /* Whether "restrict" was specified. */
254 BOOL_BITFIELD restrict_p : 1;
255 };
256
257 /* The various kinds of declarators in C. */
258 enum c_declarator_kind {
259 /* An identifier. */
260 cdk_id,
261 /* A function. */
262 cdk_function,
263 /* An array. */
264 cdk_array,
265 /* A pointer. */
266 cdk_pointer,
267 /* Parenthesized declarator with nested attributes. */
268 cdk_attrs
269 };
270
271 /* Information about the parameters in a function declarator. */
272 struct c_arg_info {
273 /* A list of parameter decls. */
274 tree parms;
275 /* A list of structure, union and enum tags defined. */
276 tree tags;
277 /* A list of argument types to go in the FUNCTION_TYPE. */
278 tree types;
279 /* A list of non-parameter decls (notably enumeration constants)
280 defined with the parameters. */
281 tree others;
282 };
283
284 /* A declarator. */
285 struct c_declarator {
286 /* The kind of declarator. */
287 enum c_declarator_kind kind;
288 /* Except for cdk_id, the contained declarator. For cdk_id, NULL. */
289 struct c_declarator *declarator;
290 location_t id_loc; /* Currently only set for cdk_id. */
291 union {
292 /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract
293 declarator. */
294 tree id;
295 /* For functions. */
296 struct c_arg_info *arg_info;
297 /* For arrays. */
298 struct {
299 /* The array dimension, or NULL for [] and [*]. */
300 tree dimen;
301 /* The qualifiers inside []. */
302 int quals;
303 /* The attributes (currently ignored) inside []. */
304 tree attrs;
305 /* Whether [static] was used. */
306 BOOL_BITFIELD static_p : 1;
307 /* Whether [*] was used. */
308 BOOL_BITFIELD vla_unspec_p : 1;
309 } array;
310 /* For pointers, the qualifiers on the pointer type. */
311 int pointer_quals;
312 /* For attributes. */
313 tree attrs;
314 } u;
315 };
316
317 /* A type name. */
318 struct c_type_name {
319 /* The declaration specifiers. */
320 struct c_declspecs *specs;
321 /* The declarator. */
322 struct c_declarator *declarator;
323 };
324
325 /* A parameter. */
326 struct c_parm {
327 /* The declaration specifiers, minus any prefix attributes. */
328 struct c_declspecs *specs;
329 /* The attributes. */
330 tree attrs;
331 /* The declarator. */
332 struct c_declarator *declarator;
333 };
334
335 /* Save and restore the variables in this file and elsewhere
336 that keep track of the progress of compilation of the current function.
337 Used for nested functions. */
338
339 struct language_function GTY(())
340 {
341 struct c_language_function base;
342 tree x_break_label;
343 tree x_cont_label;
344 struct c_switch * GTY((skip)) x_switch_stack;
345 struct c_arg_info * GTY((skip)) arg_info;
346 int returns_value;
347 int returns_null;
348 int returns_abnormally;
349 int warn_about_return_type;
350 int extern_inline;
351 };
352
353 \f
354 /* in c-parser.c */
355 extern void c_parse_init (void);
356
357 /* in c-aux-info.c */
358 extern void gen_aux_info_record (tree, int, int, int);
359
360 /* in c-decl.c */
361 extern struct obstack parser_obstack;
362 extern tree c_break_label;
363 extern tree c_cont_label;
364
365 extern int global_bindings_p (void);
366 extern void push_scope (void);
367 extern tree pop_scope (void);
368 extern void insert_block (tree);
369 extern tree pushdecl (tree);
370 extern void c_expand_body (tree);
371
372 extern void c_init_decl_processing (void);
373 extern void c_dup_lang_specific_decl (tree);
374 extern void c_print_identifier (FILE *, tree, int);
375 extern int quals_from_declspecs (const struct c_declspecs *);
376 extern struct c_declarator *build_array_declarator (tree, struct c_declspecs *,
377 bool, bool);
378 extern tree build_enumerator (tree, tree);
379 extern void check_for_loop_decls (void);
380 extern void mark_forward_parm_decls (void);
381 extern void declare_parm_level (void);
382 extern void undeclared_variable (tree, location_t);
383 extern tree declare_label (tree);
384 extern tree define_label (location_t, tree);
385 extern void finish_decl (tree, tree, tree);
386 extern tree finish_enum (tree, tree, tree);
387 extern void finish_function (void);
388 extern tree finish_struct (tree, tree, tree);
389 extern struct c_arg_info *get_parm_info (bool);
390 extern tree grokfield (struct c_declarator *, struct c_declspecs *, tree);
391 extern tree groktypename (struct c_type_name *);
392 extern tree grokparm (const struct c_parm *);
393 extern tree implicitly_declare (tree);
394 extern void keep_next_level (void);
395 extern tree lookup_name (tree);
396 extern void pending_xref_error (void);
397 extern void c_push_function_context (struct function *);
398 extern void c_pop_function_context (struct function *);
399 extern void push_parm_decl (const struct c_parm *);
400 extern tree pushdecl_top_level (tree);
401 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
402 struct c_declarator *,
403 bool);
404 extern tree builtin_function (const char *, tree, int, enum built_in_class,
405 const char *, tree);
406 extern void shadow_tag (const struct c_declspecs *);
407 extern void shadow_tag_warned (const struct c_declspecs *, int);
408 extern tree start_enum (tree);
409 extern int start_function (struct c_declspecs *, struct c_declarator *, tree);
410 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
411 tree);
412 extern tree start_struct (enum tree_code, tree);
413 extern void store_parm_decls (void);
414 extern void store_parm_decls_from (struct c_arg_info *);
415 extern tree xref_tag (enum tree_code, tree);
416 extern struct c_typespec parser_xref_tag (enum tree_code, tree);
417 extern int c_expand_decl (tree);
418 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
419 struct c_declarator *);
420 extern struct c_declarator *build_attrs_declarator (tree,
421 struct c_declarator *);
422 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
423 struct c_declarator *);
424 extern struct c_declarator *build_id_declarator (tree);
425 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
426 struct c_declarator *);
427 extern struct c_declspecs *build_null_declspecs (void);
428 extern struct c_declspecs *declspecs_add_qual (struct c_declspecs *, tree);
429 extern struct c_declspecs *declspecs_add_type (struct c_declspecs *,
430 struct c_typespec);
431 extern struct c_declspecs *declspecs_add_scspec (struct c_declspecs *, tree);
432 extern struct c_declspecs *declspecs_add_attrs (struct c_declspecs *, tree);
433 extern struct c_declspecs *finish_declspecs (struct c_declspecs *);
434
435 /* in c-objc-common.c */
436 extern int c_disregard_inline_limits (tree);
437 extern int c_cannot_inline_tree_fn (tree *);
438 extern bool c_objc_common_init (void);
439 extern bool c_missing_noreturn_ok_p (tree);
440 extern tree c_objc_common_truthvalue_conversion (tree expr);
441 extern bool c_warn_unused_global_decl (tree);
442 extern void c_initialize_diagnostics (diagnostic_context *);
443
444 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P) \
445 c_build_qualified_type ((TYPE), \
446 ((CONST_P) ? TYPE_QUAL_CONST : 0) | \
447 ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
448
449 /* in c-typeck.c */
450 extern int in_alignof;
451 extern int in_sizeof;
452 extern int in_typeof;
453
454 extern struct c_switch *c_switch_stack;
455
456 extern tree require_complete_type (tree);
457 extern int same_translation_unit_p (tree, tree);
458 extern int comptypes (tree, tree);
459 extern bool c_mark_addressable (tree);
460 extern void c_incomplete_type_error (tree, tree);
461 extern tree c_type_promotes_to (tree);
462 extern tree default_conversion (tree);
463 extern tree composite_type (tree, tree);
464 extern tree build_component_ref (tree, tree);
465 extern tree build_indirect_ref (tree, const char *);
466 extern tree build_array_ref (tree, tree);
467 extern tree build_external_ref (tree, int, location_t);
468 extern void pop_maybe_used (bool);
469 extern struct c_expr c_expr_sizeof_expr (struct c_expr);
470 extern struct c_expr c_expr_sizeof_type (struct c_type_name *);
471 extern struct c_expr parser_build_binary_op (enum tree_code, struct c_expr,
472 struct c_expr);
473 extern tree build_conditional_expr (tree, tree, tree);
474 extern tree build_compound_expr (tree, tree);
475 extern tree c_cast_expr (struct c_type_name *, tree);
476 extern tree build_c_cast (tree, tree);
477 extern tree build_modify_expr (tree, enum tree_code, tree);
478 extern void store_init_value (tree, tree);
479 extern void error_init (const char *);
480 extern void pedwarn_init (const char *);
481 extern void maybe_warn_string_init (tree, struct c_expr);
482 extern void start_init (tree, tree, int);
483 extern void finish_init (void);
484 extern void really_start_incremental_init (tree);
485 extern void push_init_level (int);
486 extern struct c_expr pop_init_level (int);
487 extern void set_init_index (tree, tree);
488 extern void set_init_label (tree);
489 extern void process_init_element (struct c_expr);
490 extern tree build_compound_literal (tree, tree);
491 extern tree c_start_case (tree);
492 extern void c_finish_case (tree);
493 extern tree build_asm_expr (tree, tree, tree, tree, bool);
494 extern tree build_asm_stmt (tree, tree);
495 extern tree c_convert_parm_for_inlining (tree, tree, tree, int);
496 extern int c_types_compatible_p (tree, tree);
497 extern tree c_begin_compound_stmt (bool);
498 extern tree c_end_compound_stmt (tree, bool);
499 extern void c_finish_if_stmt (location_t, tree, tree, tree, bool);
500 extern void c_finish_loop (location_t, tree, tree, tree, tree, tree, bool);
501 extern tree c_begin_stmt_expr (void);
502 extern tree c_finish_stmt_expr (tree);
503 extern tree c_process_expr_stmt (tree);
504 extern tree c_finish_expr_stmt (tree);
505 extern tree c_finish_return (tree);
506 extern tree c_finish_bc_stmt (tree *, bool);
507 extern tree c_finish_goto_label (tree);
508 extern tree c_finish_goto_ptr (tree);
509
510 /* Set to 0 at beginning of a function definition, set to 1 if
511 a return statement that specifies a return value is seen. */
512
513 extern int current_function_returns_value;
514
515 /* Set to 0 at beginning of a function definition, set to 1 if
516 a return statement with no argument is seen. */
517
518 extern int current_function_returns_null;
519
520 /* Set to 0 at beginning of a function definition, set to 1 if
521 a call to a noreturn function is seen. */
522
523 extern int current_function_returns_abnormally;
524
525 /* Nonzero means we are reading code that came from a system header file. */
526
527 extern int system_header_p;
528
529 /* True means global_bindings_p should return false even if the scope stack
530 says we are in file scope. */
531
532 extern bool c_override_global_bindings_to_false;
533
534 /* True means we've initialized exception handling. */
535 extern bool c_eh_initialized_p;
536
537 /* In c-decl.c */
538 extern void c_finish_incomplete_decl (tree);
539 extern void c_write_global_declarations (void);
540
541 /* In order for the format checking to accept the C frontend
542 diagnostic framework extensions, you must include this file before
543 toplev.h, not after. */
544 #define GCC_DIAG_STYLE __gcc_cdiag__
545 #if GCC_VERSION >= 3005
546 #define ATTRIBUTE_GCC_CDIAG(m, n) __attribute__ ((__format__ (GCC_DIAG_STYLE, m ,n))) ATTRIBUTE_NONNULL(m)
547 #else
548 #define ATTRIBUTE_GCC_CDIAG(m, n) ATTRIBUTE_NONNULL(m)
549 #endif
550
551 extern void pedwarn_c90 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
552 extern void pedwarn_c99 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
553
554 #endif /* ! GCC_C_TREE_H */