* target.h (struct gcc_target): Add new field to struct cxx: import_export_class.
[official-gcc.git] / gcc / c-decl.c
blob00bb5872da0d04d21271483f31bcbbc6ee6f73d8
1 /* Process declarations and variables for C compiler.
2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
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.
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.
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. */
22 /* Process declarations and symbol lookup for C front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
29 #include "config.h"
30 #include "system.h"
31 #include "coretypes.h"
32 #include "tm.h"
33 #include "intl.h"
34 #include "tree.h"
35 #include "tree-inline.h"
36 #include "rtl.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "output.h"
40 #include "expr.h"
41 #include "c-tree.h"
42 #include "toplev.h"
43 #include "ggc.h"
44 #include "tm_p.h"
45 #include "cpplib.h"
46 #include "target.h"
47 #include "debug.h"
48 #include "opts.h"
49 #include "timevar.h"
50 #include "c-common.h"
51 #include "c-pragma.h"
52 #include "langhooks.h"
53 #include "tree-mudflap.h"
54 #include "tree-gimple.h"
55 #include "diagnostic.h"
56 #include "tree-dump.h"
57 #include "cgraph.h"
58 #include "hashtab.h"
59 #include "libfuncs.h"
60 #include "except.h"
61 #include "langhooks-def.h"
63 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
64 enum decl_context
65 { NORMAL, /* Ordinary declaration */
66 FUNCDEF, /* Function definition */
67 PARM, /* Declaration of parm before function body */
68 FIELD, /* Declaration inside struct or union */
69 TYPENAME}; /* Typename (inside cast or sizeof) */
72 /* Nonzero if we have seen an invalid cross reference
73 to a struct, union, or enum, but not yet printed the message. */
74 tree pending_invalid_xref;
76 /* File and line to appear in the eventual error message. */
77 location_t pending_invalid_xref_location;
79 /* True means we've initialized exception handling. */
80 bool c_eh_initialized_p;
82 /* While defining an enum type, this is 1 plus the last enumerator
83 constant value. Note that will do not have to save this or `enum_overflow'
84 around nested function definition since such a definition could only
85 occur in an enum value expression and we don't use these variables in
86 that case. */
88 static tree enum_next_value;
90 /* Nonzero means that there was overflow computing enum_next_value. */
92 static int enum_overflow;
94 /* These #defines are for clarity in working with the information block
95 returned by get_parm_info. */
96 #define ARG_INFO_PARMS(args) TREE_PURPOSE(args)
97 #define ARG_INFO_TAGS(args) TREE_VALUE(args)
98 #define ARG_INFO_TYPES(args) TREE_CHAIN(args)
99 #define ARG_INFO_OTHERS(args) TREE_TYPE(args)
101 /* The file and line that the prototype came from if this is an
102 old-style definition; used for diagnostics in
103 store_parm_decls_oldstyle. */
105 static location_t current_function_prototype_locus;
107 /* The current statement tree. */
109 static GTY(()) struct stmt_tree_s c_stmt_tree;
111 /* State saving variables. */
112 tree c_break_label;
113 tree c_cont_label;
115 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
116 included in this invocation. Note that the current translation
117 unit is not included in this list. */
119 static GTY(()) tree all_translation_units;
121 /* A list of decls to be made automatically visible in each file scope. */
122 static GTY(()) tree visible_builtins;
124 /* Set to 0 at beginning of a function definition, set to 1 if
125 a return statement that specifies a return value is seen. */
127 int current_function_returns_value;
129 /* Set to 0 at beginning of a function definition, set to 1 if
130 a return statement with no argument is seen. */
132 int current_function_returns_null;
134 /* Set to 0 at beginning of a function definition, set to 1 if
135 a call to a noreturn function is seen. */
137 int current_function_returns_abnormally;
139 /* Set to nonzero by `grokdeclarator' for a function
140 whose return type is defaulted, if warnings for this are desired. */
142 static int warn_about_return_type;
144 /* Nonzero when starting a function declared `extern inline'. */
146 static int current_extern_inline;
148 /* True means global_bindings_p should return false even if the scope stack
149 says we are in file scope. */
150 bool c_override_global_bindings_to_false;
153 /* Each c_binding structure describes one binding of an identifier to
154 a decl. All the decls in a scope - irrespective of namespace - are
155 chained together by the ->prev field, which (as the name implies)
156 runs in reverse order. All the decls in a given namespace bound to
157 a given identifier are chained by the ->shadowed field, which runs
158 from inner to outer scopes. Finally, the ->contour field points
159 back to the relevant scope structure; this is mainly used to make
160 decls in the externals scope invisible (see below).
162 The ->decl field usually points to a DECL node, but there are two
163 exceptions. In the namespace of type tags, the bound entity is a
164 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
165 identifier is encountered, it is bound to error_mark_node to
166 suppress further errors about that identifier in the current
167 function. */
169 struct c_binding GTY((chain_next ("%h.prev")))
171 tree decl; /* the decl bound */
172 tree id; /* the identifier it's bound to */
173 struct c_binding *prev; /* the previous decl in this scope */
174 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
175 struct c_scope *contour; /* the scope in which this decl is bound */
178 #define I_SYMBOL_BINDING(node) \
179 (((struct lang_identifier *)IDENTIFIER_NODE_CHECK(node))->symbol_binding)
180 #define I_SYMBOL_DECL(node) \
181 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
183 #define I_TAG_BINDING(node) \
184 (((struct lang_identifier *)IDENTIFIER_NODE_CHECK(node))->tag_binding)
185 #define I_TAG_DECL(node) \
186 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
188 #define I_LABEL_BINDING(node) \
189 (((struct lang_identifier *)IDENTIFIER_NODE_CHECK(node))->label_binding)
190 #define I_LABEL_DECL(node) \
191 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
193 /* Each C symbol points to three linked lists of c_binding structures.
194 These describe the values of the identifier in the three different
195 namespaces defined by the language. */
197 struct lang_identifier GTY(())
199 struct c_common_identifier common_id;
200 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
201 struct c_binding *tag_binding; /* struct/union/enum tags */
202 struct c_binding *label_binding; /* labels */
205 /* Validate c-lang.c's assumptions. */
206 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
207 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
209 /* The resulting tree type. */
211 union lang_tree_node
212 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
213 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *)TYPE_NEXT_VARIANT (&%h.generic) : (union lang_tree_node *)TREE_CHAIN (&%h.generic)")))
215 union tree_node GTY ((tag ("0"),
216 desc ("tree_node_structure (&%h)")))
217 generic;
218 struct lang_identifier GTY ((tag ("1"))) identifier;
221 /* Each c_scope structure describes the complete contents of one
222 scope. Four scopes are distinguished specially: the innermost or
223 current scope, the innermost function scope, the file scope (always
224 the second to outermost) and the outermost or external scope.
226 Most declarations are recorded in the current scope.
228 All normal label declarations are recorded in the innermost
229 function scope, as are bindings of undeclared identifiers to
230 error_mark_node. (GCC permits nested functions as an extension,
231 hence the 'innermost' qualifier.) Explicitly declared labels
232 (using the __label__ extension) appear in the current scope.
234 Being in the file scope (current_scope == file_scope) causes
235 special behavior in several places below. Also, under some
236 conditions the Objective-C front end records declarations in the
237 file scope even though that isn't the current scope.
239 All declarations with external linkage are recorded in the external
240 scope, even if they aren't visible there; this models the fact that
241 such declarations are visible to the entire program, and (with a
242 bit of cleverness, see pushdecl) allows diagnosis of some violations
243 of C99 6.2.2p7 and 6.2.7p2:
245 If, within the same translation unit, the same identifier appears
246 with both internal and external linkage, the behavior is
247 undefined.
249 All declarations that refer to the same object or function shall
250 have compatible type; otherwise, the behavior is undefined.
252 Initially only the built-in declarations, which describe compiler
253 intrinsic functions plus a subset of the standard library, are in
254 this scope.
256 The order of the blocks list matters, and it is frequently appended
257 to. To avoid having to walk all the way to the end of the list on
258 each insertion, or reverse the list later, we maintain a pointer to
259 the last list entry. (FIXME: It should be feasible to use a reversed
260 list here.)
262 The bindings list is strictly in reverse order of declarations;
263 pop_scope relies on this. */
266 struct c_scope GTY((chain_next ("%h.outer")))
268 /* The scope containing this one. */
269 struct c_scope *outer;
271 /* The next outermost function scope. */
272 struct c_scope *outer_function;
274 /* All bindings in this scope. */
275 struct c_binding *bindings;
277 /* For each scope (except the global one), a chain of BLOCK nodes
278 for all the scopes that were entered and exited one level down. */
279 tree blocks;
280 tree blocks_last;
282 /* The depth of this scope. Used to keep the ->shadowed chain of
283 bindings sorted innermost to outermost. */
284 unsigned int depth : 28;
286 /* True if we are currently filling this scope with parameter
287 declarations. */
288 BOOL_BITFIELD parm_flag : 1;
290 /* True if we already complained about forward parameter decls
291 in this scope. This prevents double warnings on
292 foo (int a; int b; ...) */
293 BOOL_BITFIELD warned_forward_parm_decls : 1;
295 /* True if this is the outermost block scope of a function body.
296 This scope contains the parameters, the local variables declared
297 in the outermost block, and all the labels (except those in
298 nested functions, or declared at block scope with __label__). */
299 BOOL_BITFIELD function_body : 1;
301 /* True means make a BLOCK for this scope no matter what. */
302 BOOL_BITFIELD keep : 1;
305 /* The scope currently in effect. */
307 static GTY(()) struct c_scope *current_scope;
309 /* The innermost function scope. Ordinary (not explicitly declared)
310 labels, bindings to error_mark_node, and the lazily-created
311 bindings of __func__ and its friends get this scope. */
313 static GTY(()) struct c_scope *current_function_scope;
315 /* The C file scope. This is reset for each input translation unit. */
317 static GTY(()) struct c_scope *file_scope;
319 /* The outermost scope. This is used for all declarations with
320 external linkage, and only these, hence the name. */
322 static GTY(()) struct c_scope *external_scope;
324 /* A chain of c_scope structures awaiting reuse. */
326 static GTY((deletable)) struct c_scope *scope_freelist;
328 /* A chain of c_binding structures awaiting reuse. */
330 static GTY((deletable)) struct c_binding *binding_freelist;
332 /* Append VAR to LIST in scope SCOPE. */
333 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
334 struct c_scope *s_ = (scope); \
335 tree d_ = (decl); \
336 if (s_->list##_last) \
337 TREE_CHAIN (s_->list##_last) = d_; \
338 else \
339 s_->list = d_; \
340 s_->list##_last = d_; \
341 } while (0)
343 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
344 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
345 struct c_scope *t_ = (tscope); \
346 struct c_scope *f_ = (fscope); \
347 if (t_->to##_last) \
348 TREE_CHAIN (t_->to##_last) = f_->from; \
349 else \
350 t_->to = f_->from; \
351 t_->to##_last = f_->from##_last; \
352 } while (0)
354 /* True means unconditionally make a BLOCK for the next scope pushed. */
356 static bool keep_next_level_flag;
358 /* True means the next call to push_scope will be the outermost scope
359 of a function body, so do not push a new scope, merely cease
360 expecting parameter decls. */
362 static bool next_is_function_body;
364 /* Functions called automatically at the beginning and end of execution. */
366 tree static_ctors, static_dtors;
368 /* Forward declarations. */
369 static tree lookup_name_in_scope (tree, struct c_scope *);
370 static tree c_make_fname_decl (tree, int);
371 static tree grokdeclarator (tree, tree, enum decl_context, int, tree *);
372 static tree grokparms (tree, int);
373 static void layout_array_type (tree);
375 /* States indicating how grokdeclarator() should handle declspecs marked
376 with __attribute__((deprecated)). An object declared as
377 __attribute__((deprecated)) suppresses warnings of uses of other
378 deprecated items. */
380 enum deprecated_states {
381 DEPRECATED_NORMAL,
382 DEPRECATED_SUPPRESS
385 static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
387 void
388 c_print_identifier (FILE *file, tree node, int indent)
390 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
391 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
392 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
393 if (C_IS_RESERVED_WORD (node))
395 tree rid = ridpointers[C_RID_CODE (node)];
396 indent_to (file, indent + 4);
397 fprintf (file, "rid " HOST_PTR_PRINTF " \"%s\"",
398 (void *) rid, IDENTIFIER_POINTER (rid));
402 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
403 which may be any of several kinds of DECL or TYPE or error_mark_node,
404 in the scope SCOPE. */
405 static void
406 bind (tree name, tree decl, struct c_scope *scope)
408 struct c_binding *b, **here;
410 if (binding_freelist)
412 b = binding_freelist;
413 binding_freelist = b->prev;
415 else
416 b = ggc_alloc (sizeof (struct c_binding));
418 b->shadowed = 0;
419 b->decl = decl;
420 b->id = name;
421 b->contour = scope;
423 b->prev = scope->bindings;
424 scope->bindings = b;
426 if (!name)
427 return;
429 switch (TREE_CODE (decl))
431 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
432 case ENUMERAL_TYPE:
433 case UNION_TYPE:
434 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
435 case VAR_DECL:
436 case FUNCTION_DECL:
437 case TYPE_DECL:
438 case CONST_DECL:
439 case PARM_DECL:
440 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
442 default:
443 abort ();
446 /* Locate the appropriate place in the chain of shadowed decls
447 to insert this binding. Normally, scope == current_scope and
448 this does nothing. */
449 while (*here && (*here)->contour->depth > scope->depth)
450 here = &(*here)->shadowed;
452 b->shadowed = *here;
453 *here = b;
456 /* Clear the binding structure B, stick it on the binding_freelist,
457 and return the former value of b->prev. This is used by pop_scope
458 and get_parm_info to iterate destructively over all the bindings
459 from a given scope. */
460 static struct c_binding *
461 free_binding_and_advance (struct c_binding *b)
463 struct c_binding *prev = b->prev;
465 b->id = 0;
466 b->decl = 0;
467 b->contour = 0;
468 b->shadowed = 0;
469 b->prev = binding_freelist;
470 binding_freelist = b;
472 return prev;
476 /* Hook called at end of compilation to assume 1 elt
477 for a file-scope tentative array defn that wasn't complete before. */
479 void
480 c_finish_incomplete_decl (tree decl)
482 if (TREE_CODE (decl) == VAR_DECL)
484 tree type = TREE_TYPE (decl);
485 if (type != error_mark_node
486 && TREE_CODE (type) == ARRAY_TYPE
487 && ! DECL_EXTERNAL (decl)
488 && TYPE_DOMAIN (type) == 0)
490 warning ("%Jarray '%D' assumed to have one element", decl, decl);
492 complete_array_type (type, NULL_TREE, 1);
494 layout_decl (decl, 0);
499 /* The Objective-C front-end often needs to determine the current scope. */
501 void *
502 get_current_scope (void)
504 return current_scope;
507 /* The following function is used only by Objective-C. It needs to live here
508 because it accesses the innards of c_scope. */
510 void
511 objc_mark_locals_volatile (void *enclosing_blk)
513 struct c_scope *scope;
514 struct c_binding *b;
516 for (scope = current_scope;
517 scope && scope != enclosing_blk;
518 scope = scope->outer)
520 for (b = scope->bindings; b; b = b->prev)
522 if (TREE_CODE (b->decl) == VAR_DECL
523 || TREE_CODE (b->decl) == PARM_DECL)
525 C_DECL_REGISTER (b->decl) = 0;
526 DECL_REGISTER (b->decl) = 0;
527 TREE_THIS_VOLATILE (b->decl) = 1;
531 /* Do not climb up past the current function. */
532 if (scope->function_body)
533 break;
537 /* Nonzero if we are currently in file scope. */
540 global_bindings_p (void)
542 return current_scope == file_scope && !c_override_global_bindings_to_false;
545 void
546 keep_next_level (void)
548 keep_next_level_flag = true;
551 /* Identify this scope as currently being filled with parameters. */
553 void
554 declare_parm_level (void)
556 current_scope->parm_flag = true;
559 void
560 push_scope (void)
562 if (next_is_function_body)
564 /* This is the transition from the parameters to the top level
565 of the function body. These are the same scope
566 (C99 6.2.1p4,6) so we do not push another scope structure.
567 next_is_function_body is set only by store_parm_decls, which
568 in turn is called when and only when we are about to
569 encounter the opening curly brace for the function body.
571 The outermost block of a function always gets a BLOCK node,
572 because the debugging output routines expect that each
573 function has at least one BLOCK. */
574 current_scope->parm_flag = false;
575 current_scope->function_body = true;
576 current_scope->keep = true;
577 current_scope->outer_function = current_function_scope;
578 current_function_scope = current_scope;
580 keep_next_level_flag = false;
581 next_is_function_body = false;
583 else
585 struct c_scope *scope;
586 if (scope_freelist)
588 scope = scope_freelist;
589 scope_freelist = scope->outer;
591 else
592 scope = ggc_alloc_cleared (sizeof (struct c_scope));
594 scope->keep = keep_next_level_flag;
595 scope->outer = current_scope;
596 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
598 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
599 possible. */
600 if (current_scope && scope->depth == 0)
602 scope->depth--;
603 sorry ("GCC supports only %u nested scopes\n", scope->depth);
606 current_scope = scope;
607 keep_next_level_flag = false;
611 /* Exit a scope. Restore the state of the identifier-decl mappings
612 that were in effect when this scope was entered. Return a BLOCK
613 node containing all the DECLs in this scope that are of interest
614 to debug info generation. */
616 tree
617 pop_scope (void)
619 struct c_scope *scope = current_scope;
620 tree block, context, p;
621 struct c_binding *b;
623 bool functionbody = scope->function_body;
624 bool keep = functionbody || scope->keep || scope->bindings;
626 /* If appropriate, create a BLOCK to record the decls for the life
627 of this function. */
628 block = 0;
629 if (keep)
631 block = make_node (BLOCK);
632 BLOCK_SUBBLOCKS (block) = scope->blocks;
633 TREE_USED (block) = 1;
635 /* In each subblock, record that this is its superior. */
636 for (p = scope->blocks; p; p = TREE_CHAIN (p))
637 BLOCK_SUPERCONTEXT (p) = block;
639 BLOCK_VARS (block) = 0;
642 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
643 scope must be set so that they point to the appropriate
644 construct, i.e. either to the current FUNCTION_DECL node, or
645 else to the BLOCK node we just constructed.
647 Note that for tagged types whose scope is just the formal
648 parameter list for some function type specification, we can't
649 properly set their TYPE_CONTEXTs here, because we don't have a
650 pointer to the appropriate FUNCTION_TYPE node readily available
651 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
652 type nodes get set in `grokdeclarator' as soon as we have created
653 the FUNCTION_TYPE node which will represent the "scope" for these
654 "parameter list local" tagged types. */
655 if (scope->function_body)
656 context = current_function_decl;
657 else if (scope == file_scope)
659 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
660 TREE_CHAIN (file_decl) = all_translation_units;
661 all_translation_units = file_decl;
662 context = file_decl;
664 else
665 context = block;
667 /* Clear all bindings in this scope. */
668 for (b = scope->bindings; b; b = free_binding_and_advance (b))
670 p = b->decl;
671 switch (TREE_CODE (p))
673 case LABEL_DECL:
674 /* Warnings for unused labels, errors for undefined labels. */
675 if (TREE_USED (p) && !DECL_INITIAL (p))
677 error ("%Jlabel `%D' used but not defined", p, p);
678 DECL_INITIAL (p) = error_mark_node;
680 else if (!TREE_USED (p) && warn_unused_label)
682 if (DECL_INITIAL (p))
683 warning ("%Jlabel `%D' defined but not used", p, p);
684 else
685 warning ("%Jlabel `%D' declared but not defined", p, p);
687 /* Labels go in BLOCK_VARS. */
688 TREE_CHAIN (p) = BLOCK_VARS (block);
689 BLOCK_VARS (block) = p;
691 #ifdef ENABLE_CHECKING
692 if (I_LABEL_BINDING (b->id) != b) abort ();
693 #endif
694 I_LABEL_BINDING (b->id) = b->shadowed;
695 break;
697 case ENUMERAL_TYPE:
698 case UNION_TYPE:
699 case RECORD_TYPE:
700 TYPE_CONTEXT (p) = context;
702 /* Types may not have tag-names, in which case the type
703 appears in the bindings list with b->id NULL. */
704 if (b->id)
706 #ifdef ENABLE_CHECKING
707 if (I_TAG_BINDING (b->id) != b) abort ();
708 #endif
709 I_TAG_BINDING (b->id) = b->shadowed;
711 break;
713 case FUNCTION_DECL:
714 /* Propagate TREE_ADDRESSABLE from nested functions to their
715 containing functions. */
716 if (! TREE_ASM_WRITTEN (p)
717 && DECL_INITIAL (p) != 0
718 && TREE_ADDRESSABLE (p)
719 && DECL_ABSTRACT_ORIGIN (p) != 0
720 && DECL_ABSTRACT_ORIGIN (p) != p)
721 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
722 goto common_symbol;
724 case VAR_DECL:
725 /* Warnings for unused variables. Keep this in sync with
726 stmt.c:warn_about_unused_variables, which we cannot use
727 since it expects a different data structure. */
728 if (warn_unused_variable
729 && !TREE_USED (p)
730 && !DECL_IN_SYSTEM_HEADER (p)
731 && DECL_NAME (p)
732 && !DECL_ARTIFICIAL (p)
733 && (scope != file_scope
734 || (TREE_STATIC (p) && !TREE_PUBLIC (p)
735 && !TREE_THIS_VOLATILE (p)))
736 && scope != external_scope)
737 warning ("%Junused variable `%D'", p, p);
739 /* Fall through. */
740 case TYPE_DECL:
741 case CONST_DECL:
742 common_symbol:
743 /* All of these go in BLOCK_VARS, but only if this is the
744 binding in the home scope. */
745 if (!C_DECL_IN_EXTERNAL_SCOPE (p) || scope == external_scope)
747 TREE_CHAIN (p) = BLOCK_VARS (block);
748 BLOCK_VARS (block) = p;
750 /* If this is the file scope, must set DECL_CONTEXT on these. */
751 if (!C_DECL_IN_EXTERNAL_SCOPE (p) && scope == file_scope)
752 DECL_CONTEXT (p) = context;
754 /* Fall through. */
755 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
756 already been put there by store_parm_decls. Unused-
757 parameter warnings are handled by function.c.
758 error_mark_node obviously does not go in BLOCK_VARS and
759 does not get unused-variable warnings. */
760 case PARM_DECL:
761 case ERROR_MARK:
762 /* It is possible for a decl not to have a name. We get
763 here with b->id NULL in this case. */
764 if (b->id)
766 #ifdef ENABLE_CHECKING
767 if (I_SYMBOL_BINDING (b->id) != b) abort ();
768 #endif
769 I_SYMBOL_BINDING (b->id) = b->shadowed;
771 break;
773 default:
774 abort ();
779 /* Dispose of the block that we just made inside some higher level. */
780 if ((scope->function_body || scope == file_scope) && context)
782 DECL_INITIAL (context) = block;
783 BLOCK_SUPERCONTEXT (block) = context;
785 else if (scope->outer)
787 if (block)
788 SCOPE_LIST_APPEND (scope->outer, blocks, block);
789 /* If we did not make a block for the scope just exited, any
790 blocks made for inner scopes must be carried forward so they
791 will later become subblocks of something else. */
792 else if (scope->blocks)
793 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
796 /* Pop the current scope, and free the structure for reuse. */
797 current_scope = scope->outer;
798 if (scope->function_body)
799 current_function_scope = scope->outer_function;
801 memset (scope, 0, sizeof (struct c_scope));
802 scope->outer = scope_freelist;
803 scope_freelist = scope;
805 return block;
808 void
809 push_file_scope (void)
811 tree decl;
813 if (file_scope)
814 return;
816 push_scope ();
817 file_scope = current_scope;
819 start_fname_decls ();
821 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
822 bind (DECL_NAME (decl), decl, file_scope);
825 void
826 pop_file_scope (void)
828 /* In case there were missing closebraces, get us back to the global
829 binding level. */
830 while (current_scope != file_scope)
831 pop_scope ();
833 /* __FUNCTION__ is defined at file scope (""). This
834 call may not be necessary as my tests indicate it
835 still works without it. */
836 finish_fname_decls ();
838 /* Kludge: don't actually pop the file scope if generating a
839 precompiled header, so that macros and local symbols are still
840 visible to the PCH generator. */
841 if (pch_file)
842 return;
844 /* And pop off the file scope. */
845 pop_scope ();
846 file_scope = 0;
848 cpp_undef_all (parse_in);
851 /* Insert BLOCK at the end of the list of subblocks of the current
852 scope. This is used when a BIND_EXPR is expanded, to handle the
853 BLOCK node inside the BIND_EXPR. */
855 void
856 insert_block (tree block)
858 TREE_USED (block) = 1;
859 SCOPE_LIST_APPEND (current_scope, blocks, block);
862 /* Push a definition or a declaration of struct, union or enum tag "name".
863 "type" should be the type node.
864 We assume that the tag "name" is not already defined.
866 Note that the definition may really be just a forward reference.
867 In that case, the TYPE_SIZE will be zero. */
869 static void
870 pushtag (tree name, tree type)
872 /* Record the identifier as the type's name if it has none. */
873 if (name && !TYPE_NAME (type))
874 TYPE_NAME (type) = name;
875 bind (name, type, current_scope);
877 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
878 tagged type we just added to the current scope. This fake
879 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
880 to output a representation of a tagged type, and it also gives
881 us a convenient place to record the "scope start" address for the
882 tagged type. */
884 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
886 /* An approximation for now, so we can tell this is a function-scope tag.
887 This will be updated in pop_scope. */
888 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
891 /* Subroutine of compare_decls. Allow harmless mismatches in return
892 and argument types provided that the type modes match. This function
893 return a unified type given a suitable match, and 0 otherwise. */
895 static tree
896 match_builtin_function_types (tree newtype, tree oldtype)
898 tree newrettype, oldrettype;
899 tree newargs, oldargs;
900 tree trytype, tryargs;
902 /* Accept the return type of the new declaration if same modes. */
903 oldrettype = TREE_TYPE (oldtype);
904 newrettype = TREE_TYPE (newtype);
906 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
907 return 0;
909 oldargs = TYPE_ARG_TYPES (oldtype);
910 newargs = TYPE_ARG_TYPES (newtype);
911 tryargs = newargs;
913 while (oldargs || newargs)
915 if (! oldargs
916 || ! newargs
917 || ! TREE_VALUE (oldargs)
918 || ! TREE_VALUE (newargs)
919 || TYPE_MODE (TREE_VALUE (oldargs))
920 != TYPE_MODE (TREE_VALUE (newargs)))
921 return 0;
923 oldargs = TREE_CHAIN (oldargs);
924 newargs = TREE_CHAIN (newargs);
927 trytype = build_function_type (newrettype, tryargs);
928 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
931 /* Subroutine of diagnose_mismatched_decls. Check for function type
932 mismatch involving an empty arglist vs a nonempty one and give clearer
933 diagnostics. */
934 static void
935 diagnose_arglist_conflict (tree newdecl, tree olddecl,
936 tree newtype, tree oldtype)
938 tree t;
940 if (TREE_CODE (olddecl) != FUNCTION_DECL
941 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
942 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
944 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
945 return;
947 t = TYPE_ARG_TYPES (oldtype);
948 if (t == 0)
949 t = TYPE_ARG_TYPES (newtype);
950 for (; t; t = TREE_CHAIN (t))
952 tree type = TREE_VALUE (t);
954 if (TREE_CHAIN (t) == 0
955 && TYPE_MAIN_VARIANT (type) != void_type_node)
957 inform ("a parameter list with an ellipsis can't match "
958 "an empty parameter name list declaration");
959 break;
962 if (c_type_promotes_to (type) != type)
964 inform ("an argument type that has a default promotion can't match "
965 "an empty parameter name list declaration");
966 break;
971 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
972 old-style function definition, NEWDECL is a prototype declaration.
973 Diagnose inconsistencies in the argument list. Returns TRUE if
974 the prototype is compatible, FALSE if not. */
975 static bool
976 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
978 tree newargs, oldargs;
979 int i;
981 /* ??? Elsewhere TYPE_MAIN_VARIANT is not used in this context. */
982 #define END_OF_ARGLIST(t) (TYPE_MAIN_VARIANT (t) == void_type_node)
984 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
985 newargs = TYPE_ARG_TYPES (newtype);
986 i = 1;
988 for (;;)
990 tree oldargtype = TREE_VALUE (oldargs);
991 tree newargtype = TREE_VALUE (newargs);
993 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
994 break;
996 /* Reaching the end of just one list means the two decls don't
997 agree on the number of arguments. */
998 if (END_OF_ARGLIST (oldargtype))
1000 error ("%Jprototype for '%D' declares more arguments "
1001 "than previous old-style definition", newdecl, newdecl);
1002 return false;
1004 else if (END_OF_ARGLIST (newargtype))
1006 error ("%Jprototype for '%D' declares fewer arguments "
1007 "than previous old-style definition", newdecl, newdecl);
1008 return false;
1011 /* Type for passing arg must be consistent with that declared
1012 for the arg. */
1013 else if (! comptypes (oldargtype, newargtype))
1015 error ("%Jprototype for '%D' declares arg %d with incompatible type",
1016 newdecl, newdecl, i);
1017 return false;
1020 oldargs = TREE_CHAIN (oldargs);
1021 newargs = TREE_CHAIN (newargs);
1022 i++;
1025 /* If we get here, no errors were found, but do issue a warning
1026 for this poor-style construct. */
1027 warning ("%Jprototype for '%D' follows non-prototype definition",
1028 newdecl, newdecl);
1029 return true;
1030 #undef END_OF_ARGLIST
1033 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1034 first in a pair of mismatched declarations, using the diagnostic
1035 function DIAG. */
1036 static void
1037 locate_old_decl (tree decl, void (*diag)(const char *, ...))
1039 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1041 else if (DECL_INITIAL (decl))
1042 diag (N_("%Jprevious definition of '%D' was here"), decl, decl);
1043 else if (C_DECL_IMPLICIT (decl))
1044 diag (N_("%Jprevious implicit declaration of '%D' was here"), decl, decl);
1045 else
1046 diag (N_("%Jprevious declaration of '%D' was here"), decl, decl);
1049 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1050 Returns true if the caller should proceed to merge the two, false
1051 if OLDDECL should simply be discarded. As a side effect, issues
1052 all necessary diagnostics for invalid or poor-style combinations.
1053 If it returns true, writes the types of NEWDECL and OLDDECL to
1054 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1055 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1057 static bool
1058 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1059 tree *newtypep, tree *oldtypep)
1061 tree newtype, oldtype;
1062 bool pedwarned = false;
1063 bool warned = false;
1065 /* If we have error_mark_node for either decl or type, just discard
1066 the previous decl - we're in an error cascade already. */
1067 if (olddecl == error_mark_node || newdecl == error_mark_node)
1068 return false;
1069 *oldtypep = oldtype = TREE_TYPE (olddecl);
1070 *newtypep = newtype = TREE_TYPE (newdecl);
1071 if (oldtype == error_mark_node || newtype == error_mark_node)
1072 return false;
1074 /* Two different categories of symbol altogether. This is an error
1075 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1076 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1078 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1079 && DECL_BUILT_IN (olddecl)
1080 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1082 error ("%J'%D' redeclared as different kind of symbol",
1083 newdecl, newdecl);
1084 locate_old_decl (olddecl, error);
1086 else if (TREE_PUBLIC (newdecl))
1087 warning ("%Jbuilt-in function '%D' declared as non-function",
1088 newdecl, newdecl);
1089 else if (warn_shadow)
1090 warning ("%Jdeclaration of '%D' shadows a built-in function",
1091 newdecl, newdecl);
1092 return false;
1095 if (!comptypes (oldtype, newtype))
1097 if (TREE_CODE (olddecl) == FUNCTION_DECL
1098 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1100 /* Accept harmless mismatch in function types.
1101 This is for the ffs and fprintf builtins. */
1102 tree trytype = match_builtin_function_types (newtype, oldtype);
1104 if (trytype && comptypes (newtype, trytype))
1105 *oldtypep = oldtype = trytype;
1106 else
1108 /* If types don't match for a built-in, throw away the
1109 built-in. No point in calling locate_old_decl here, it
1110 won't print anything. */
1111 warning ("%Jconflicting types for built-in function '%D'",
1112 newdecl, newdecl);
1113 return false;
1116 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1117 && DECL_IS_BUILTIN (olddecl))
1119 /* A conflicting function declaration for a predeclared
1120 function that isn't actually built in. Objective C uses
1121 these. The new declaration silently overrides everything
1122 but the volatility (i.e. noreturn) indication. See also
1123 below. FIXME: Make Objective C use normal builtins. */
1124 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1125 return false;
1127 /* Permit void foo (...) to match int foo (...) if the latter is
1128 the definition and implicit int was used. See
1129 c-torture/compile/920625-2.c. */
1130 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1131 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1132 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1133 && C_FUNCTION_IMPLICIT_INT (newdecl))
1135 pedwarn ("%Jconflicting types for '%D'", newdecl, newdecl);
1136 /* Make sure we keep void as the return type. */
1137 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1138 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1139 pedwarned = true;
1141 else
1143 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1144 error ("%J conflicting type qualifiers for '%D'", newdecl, newdecl);
1145 else
1146 error ("%Jconflicting types for '%D'", newdecl, newdecl);
1147 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1148 locate_old_decl (olddecl, error);
1149 return false;
1153 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1154 but silently ignore the redeclaration if either is in a system
1155 header. (Conflicting redeclarations were handled above.) */
1156 if (TREE_CODE (newdecl) == TYPE_DECL)
1158 if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
1159 return true; /* Allow OLDDECL to continue in use. */
1161 error ("%Jredefinition of typedef '%D'", newdecl, newdecl);
1162 locate_old_decl (olddecl, error);
1163 return false;
1166 /* Function declarations can either be 'static' or 'extern' (no
1167 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1168 can never conflict with each other on account of linkage (6.2.2p4).
1169 Multiple definitions are not allowed (6.9p3,5) but GCC permits
1170 two definitions if one is 'extern inline' and one is not. The non-
1171 extern-inline definition supersedes the extern-inline definition. */
1172 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1174 /* If you declare a built-in function name as static, or
1175 define the built-in with an old-style definition (so we
1176 can't validate the argument list) the built-in definition is
1177 overridden, but optionally warn this was a bad choice of name. */
1178 if (DECL_BUILT_IN (olddecl)
1179 && !C_DECL_DECLARED_BUILTIN (olddecl)
1180 && (!TREE_PUBLIC (newdecl)
1181 || (DECL_INITIAL (newdecl)
1182 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1184 if (warn_shadow)
1185 warning ("%Jdeclaration of '%D' shadows a built-in function",
1186 newdecl, newdecl);
1187 /* Discard the old built-in function. */
1188 return false;
1191 if (DECL_INITIAL (newdecl))
1193 if (DECL_INITIAL (olddecl)
1194 && !(DECL_DECLARED_INLINE_P (olddecl)
1195 && DECL_EXTERNAL (olddecl)
1196 && !(DECL_DECLARED_INLINE_P (newdecl)
1197 && DECL_EXTERNAL (newdecl))))
1199 error ("%Jredefinition of '%D'", newdecl, newdecl);
1200 locate_old_decl (olddecl, error);
1201 return false;
1204 /* If we have a prototype after an old-style function definition,
1205 the argument types must be checked specially. */
1206 else if (DECL_INITIAL (olddecl)
1207 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1208 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1209 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1211 locate_old_decl (olddecl, error);
1212 return false;
1214 /* Mismatched non-static and static is considered poor style.
1215 We only diagnose static then non-static if -Wtraditional,
1216 because it is the most convenient way to get some effects
1217 (see e.g. what unwind-dw2-fde-glibc.c does to the definition
1218 of _Unwind_Find_FDE in unwind-dw2-fde.c). Revisit? */
1219 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1221 /* A static function declaration for a predeclared function
1222 that isn't actually built in, silently overrides the
1223 default. Objective C uses these. See also above.
1224 FIXME: Make Objective C use normal builtins. */
1225 if (TREE_CODE (olddecl) == FUNCTION_DECL
1226 && DECL_IS_BUILTIN (olddecl))
1227 return false;
1228 else
1230 warning ("%Jstatic declaration of '%D' follows "
1231 "non-static declaration", newdecl, newdecl);
1232 warned = true;
1235 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl)
1236 && warn_traditional)
1238 warning ("%Jnon-static declaration of '%D' follows "
1239 "static declaration", newdecl, newdecl);
1240 warned = true;
1243 else if (TREE_CODE (newdecl) == VAR_DECL)
1245 /* Only variables can be thread-local, and all declarations must
1246 agree on this property. */
1247 if (DECL_THREAD_LOCAL (newdecl) != DECL_THREAD_LOCAL (olddecl))
1249 if (DECL_THREAD_LOCAL (newdecl))
1250 error ("%Jthread-local declaration of '%D' follows "
1251 "non-thread-local declaration", newdecl, newdecl);
1252 else
1253 error ("%Jnon-thread-local declaration of '%D' follows "
1254 "thread-local declaration", newdecl, newdecl);
1256 locate_old_decl (olddecl, error);
1257 return false;
1260 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1261 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1263 error ("%Jredefinition of '%D'", newdecl, newdecl);
1264 locate_old_decl (olddecl, error);
1265 return false;
1268 /* Objects declared at file scope: if at least one is 'extern',
1269 it's fine (6.2.2p4); otherwise the linkage must agree (6.2.2p7). */
1270 if (DECL_FILE_SCOPE_P (newdecl))
1272 if (!DECL_EXTERNAL (newdecl)
1273 && !DECL_EXTERNAL (olddecl)
1274 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1276 if (TREE_PUBLIC (newdecl))
1277 error ("%Jnon-static declaration of '%D' follows "
1278 "static declaration", newdecl, newdecl);
1279 else
1280 error ("%Jstatic declaration of '%D' follows "
1281 "non-static declaration", newdecl, newdecl);
1283 locate_old_decl (olddecl, error);
1284 return false;
1287 /* Two objects with the same name declared at the same block
1288 scope must both be external references (6.7p3). */
1289 else if (DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl)
1290 && (!DECL_EXTERNAL (newdecl) || !DECL_EXTERNAL (olddecl)))
1292 if (DECL_EXTERNAL (newdecl))
1293 error ("%Jextern declaration of '%D' follows "
1294 "declaration with no linkage", newdecl, newdecl);
1295 else if (DECL_EXTERNAL (olddecl))
1296 error ("%Jdeclaration of '%D' with no linkage follows "
1297 "extern declaration", newdecl, newdecl);
1298 else
1299 error ("%Jredeclaration of '%D' with no linkage",
1300 newdecl, newdecl);
1302 locate_old_decl (olddecl, error);
1303 return false;
1307 /* warnings */
1308 /* All decls must agree on a non-default visibility. */
1309 if (DECL_VISIBILITY (newdecl) != VISIBILITY_DEFAULT
1310 && DECL_VISIBILITY (olddecl) != VISIBILITY_DEFAULT
1311 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1313 warning ("%Jredeclaration of '%D' with different visibility "
1314 "(old visibility preserved)", newdecl, newdecl);
1315 warned = true;
1318 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1320 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1321 if (DECL_DECLARED_INLINE_P (newdecl)
1322 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1324 warning ("%Jinline declaration of '%D' follows "
1325 "declaration with attribute noinline", newdecl, newdecl);
1326 warned = true;
1328 else if (DECL_DECLARED_INLINE_P (olddecl)
1329 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1331 warning ("%Jdeclaration of '%D' with attribute noinline follows "
1332 "inline declaration ", newdecl, newdecl);
1333 warned = true;
1336 /* Inline declaration after use or definition.
1337 ??? Should we still warn about this now we have unit-at-a-time
1338 mode and can get it right? */
1339 if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl))
1341 if (TREE_USED (olddecl))
1343 warning ("%J'%D' declared inline after being called",
1344 olddecl, olddecl);
1345 warned = true;
1347 else if (DECL_INITIAL (olddecl))
1349 warning ("%J'%D' declared inline after its definition",
1350 olddecl, olddecl);
1351 warned = true;
1355 else /* PARM_DECL, VAR_DECL */
1357 /* Redeclaration of a parameter is a constraint violation (this is
1358 not explicitly stated, but follows from C99 6.7p3 [no more than
1359 one declaration of the same identifier with no linkage in the
1360 same scope, except type tags] and 6.2.2p6 [parameters have no
1361 linkage]). We must check for a forward parameter declaration,
1362 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1363 an extension, the mandatory diagnostic for which is handled by
1364 mark_forward_parm_decls. */
1366 if (TREE_CODE (newdecl) == PARM_DECL
1367 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1369 error ("%Jredefinition of parameter '%D'", newdecl, newdecl);
1370 locate_old_decl (olddecl, error);
1371 return false;
1375 /* Optional warning for completely redundant decls. */
1376 if (!warned && !pedwarned
1377 && warn_redundant_decls
1378 /* Don't warn about a function declaration followed by a
1379 definition. */
1380 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1381 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1382 /* Don't warn about an extern followed by a definition. */
1383 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1384 /* Don't warn about forward parameter decls. */
1385 && !(TREE_CODE (newdecl) == PARM_DECL
1386 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl)))
1388 warning ("%Jredundant redeclaration of '%D'", newdecl, newdecl);
1389 warned = true;
1392 /* Report location of previous decl/defn in a consistent manner. */
1393 if (warned || pedwarned)
1394 locate_old_decl (olddecl, pedwarned ? pedwarn : warning);
1396 return true;
1399 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1400 consistent with OLDDECL, but carries new information. Merge the
1401 new information into OLDDECL. This function issues no
1402 diagnostics. */
1404 static void
1405 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1407 int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1408 && DECL_INITIAL (newdecl) != 0);
1410 /* For real parm decl following a forward decl, rechain the old decl
1411 in its new location and clear TREE_ASM_WRITTEN (it's not a
1412 forward decl anymore). */
1413 if (TREE_CODE (newdecl) == PARM_DECL
1414 && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
1416 struct c_binding *b, **here;
1418 for (here = &current_scope->bindings; *here; here = &(*here)->prev)
1419 if ((*here)->decl == olddecl)
1420 goto found;
1421 abort ();
1423 found:
1424 b = *here;
1425 *here = b->prev;
1426 b->prev = current_scope->bindings;
1427 current_scope->bindings = b;
1429 TREE_ASM_WRITTEN (olddecl) = 0;
1432 DECL_ATTRIBUTES (newdecl)
1433 = targetm.merge_decl_attributes (olddecl, newdecl);
1435 /* Merge the data types specified in the two decls. */
1436 TREE_TYPE (newdecl)
1437 = TREE_TYPE (olddecl)
1438 = composite_type (newtype, oldtype);
1440 /* Lay the type out, unless already done. */
1441 if (oldtype != TREE_TYPE (newdecl))
1443 if (TREE_TYPE (newdecl) != error_mark_node)
1444 layout_type (TREE_TYPE (newdecl));
1445 if (TREE_CODE (newdecl) != FUNCTION_DECL
1446 && TREE_CODE (newdecl) != TYPE_DECL
1447 && TREE_CODE (newdecl) != CONST_DECL)
1448 layout_decl (newdecl, 0);
1450 else
1452 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1453 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1454 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1455 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1456 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1457 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1459 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1460 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1464 /* Keep the old rtl since we can safely use it. */
1465 COPY_DECL_RTL (olddecl, newdecl);
1467 /* Merge the type qualifiers. */
1468 if (TREE_READONLY (newdecl))
1469 TREE_READONLY (olddecl) = 1;
1471 if (TREE_THIS_VOLATILE (newdecl))
1473 TREE_THIS_VOLATILE (olddecl) = 1;
1474 if (TREE_CODE (newdecl) == VAR_DECL)
1475 make_var_volatile (newdecl);
1478 /* Keep source location of definition rather than declaration. */
1479 if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1480 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1482 /* Merge the unused-warning information. */
1483 if (DECL_IN_SYSTEM_HEADER (olddecl))
1484 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1485 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1486 DECL_IN_SYSTEM_HEADER (olddecl) = 1;
1488 /* Merge the initialization information. */
1489 if (DECL_INITIAL (newdecl) == 0)
1490 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1492 /* Merge the section attribute.
1493 We want to issue an error if the sections conflict but that must be
1494 done later in decl_attributes since we are called before attributes
1495 are assigned. */
1496 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1497 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1499 /* Copy the assembler name.
1500 Currently, it can only be defined in the prototype. */
1501 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1503 /* If either declaration has a nondefault visibility, use it. */
1504 if (DECL_VISIBILITY (olddecl) != VISIBILITY_DEFAULT)
1505 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1507 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1509 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1510 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1511 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1512 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1513 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1514 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1515 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1516 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1517 DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
1520 /* Merge the storage class information. */
1521 merge_weak (newdecl, olddecl);
1523 /* For functions, static overrides non-static. */
1524 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1526 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1527 /* This is since we don't automatically
1528 copy the attributes of NEWDECL into OLDDECL. */
1529 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1530 /* If this clears `static', clear it in the identifier too. */
1531 if (! TREE_PUBLIC (olddecl))
1532 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1534 if (DECL_EXTERNAL (newdecl))
1536 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1537 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1539 /* An extern decl does not override previous storage class. */
1540 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1541 if (! DECL_EXTERNAL (newdecl))
1543 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1544 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1547 else
1549 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1550 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1553 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1555 /* If we're redefining a function previously defined as extern
1556 inline, make sure we emit debug info for the inline before we
1557 throw it away, in case it was inlined into a function that hasn't
1558 been written out yet. */
1559 if (new_is_definition && DECL_INITIAL (olddecl))
1561 if (TREE_USED (olddecl)
1562 /* In unit-at-a-time mode we never inline re-defined extern
1563 inline functions. */
1564 && !flag_unit_at_a_time
1565 && cgraph_function_possibly_inlined_p (olddecl))
1566 (*debug_hooks->outlining_inline_function) (olddecl);
1568 /* The new defn must not be inline. */
1569 DECL_INLINE (newdecl) = 0;
1570 DECL_UNINLINABLE (newdecl) = 1;
1572 else
1574 /* If either decl says `inline', this fn is inline,
1575 unless its definition was passed already. */
1576 if (DECL_DECLARED_INLINE_P (newdecl)
1577 || DECL_DECLARED_INLINE_P (olddecl))
1578 DECL_DECLARED_INLINE_P (newdecl) = 1;
1580 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1581 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1584 if (DECL_BUILT_IN (olddecl))
1586 /* If redeclaring a builtin function, it stays built in.
1587 But it gets tagged as having been declared. */
1588 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1589 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1590 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1593 /* Also preserve various other info from the definition. */
1594 if (! new_is_definition)
1596 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1597 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1598 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1599 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1600 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1602 /* Set DECL_INLINE on the declaration if we've got a body
1603 from which to instantiate. */
1604 if (DECL_INLINE (olddecl) && ! DECL_UNINLINABLE (newdecl))
1606 DECL_INLINE (newdecl) = 1;
1607 DECL_ABSTRACT_ORIGIN (newdecl)
1608 = DECL_ABSTRACT_ORIGIN (olddecl);
1611 else
1613 /* If a previous declaration said inline, mark the
1614 definition as inlinable. */
1615 if (DECL_DECLARED_INLINE_P (newdecl)
1616 && ! DECL_UNINLINABLE (newdecl))
1617 DECL_INLINE (newdecl) = 1;
1621 /* This bit must not get wiped out. */
1622 C_DECL_IN_EXTERNAL_SCOPE (newdecl) |= C_DECL_IN_EXTERNAL_SCOPE (olddecl);
1624 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1625 But preserve OLDDECL's DECL_UID. */
1627 unsigned olddecl_uid = DECL_UID (olddecl);
1629 memcpy ((char *) olddecl + sizeof (struct tree_common),
1630 (char *) newdecl + sizeof (struct tree_common),
1631 sizeof (struct tree_decl) - sizeof (struct tree_common));
1632 DECL_UID (olddecl) = olddecl_uid;
1635 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1636 so that encode_section_info has a chance to look at the new decl
1637 flags and attributes. */
1638 if (DECL_RTL_SET_P (olddecl)
1639 && (TREE_CODE (olddecl) == FUNCTION_DECL
1640 || (TREE_CODE (olddecl) == VAR_DECL
1641 && TREE_STATIC (olddecl))))
1642 make_decl_rtl (olddecl, NULL);
1645 /* Handle when a new declaration NEWDECL has the same name as an old
1646 one OLDDECL in the same binding contour. Prints an error message
1647 if appropriate.
1649 If safely possible, alter OLDDECL to look like NEWDECL, and return
1650 true. Otherwise, return false. */
1652 static bool
1653 duplicate_decls (tree newdecl, tree olddecl)
1655 tree newtype = NULL, oldtype = NULL;
1657 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1658 return false;
1660 merge_decls (newdecl, olddecl, newtype, oldtype);
1661 return true;
1665 /* Check whether decl-node NEW shadows an existing declaration. */
1666 static void
1667 warn_if_shadowing (tree new)
1669 struct c_binding *b;
1671 /* Shadow warnings wanted? */
1672 if (!warn_shadow
1673 /* No shadow warnings for internally generated vars. */
1674 || DECL_IS_BUILTIN (new)
1675 /* No shadow warnings for vars made for inlining. */
1676 || DECL_FROM_INLINE (new)
1677 /* Don't warn about the parm names in function declarator
1678 within a function declarator. It would be nice to avoid
1679 warning in any function declarator in a declaration, as
1680 opposed to a definition, but there is no way to tell
1681 it's not a definition at this point. */
1682 || (TREE_CODE (new) == PARM_DECL && current_scope->outer->parm_flag))
1683 return;
1685 /* Is anything being shadowed? Do not be confused by a second binding
1686 to the same decl in the externals scope. */
1687 for (b = I_SYMBOL_BINDING (DECL_NAME (new)); b; b = b->shadowed)
1688 if (b->decl && b->decl != new && b->contour != external_scope)
1690 tree old = b->decl;
1692 if (TREE_CODE (old) == PARM_DECL)
1693 warning ("%Jdeclaration of '%D' shadows a parameter", new, new);
1694 else if (DECL_FILE_SCOPE_P (old))
1695 warning ("%Jdeclaration of '%D' shadows a global declaration",
1696 new, new);
1697 else if (TREE_CODE (old) == FUNCTION_DECL && DECL_BUILT_IN (old))
1698 warning ("%Jdeclaration of '%D' shadows a built-in function",
1699 new, new);
1700 else
1701 warning ("%Jdeclaration of '%D' shadows a previous local", new, new);
1703 if (TREE_CODE (old) != FUNCTION_DECL || !DECL_BUILT_IN (old))
1704 warning ("%Jshadowed declaration is here", old);
1706 break;
1711 /* Subroutine of pushdecl.
1713 X is a TYPE_DECL for a typedef statement. Create a brand new
1714 ..._TYPE node (which will be just a variant of the existing
1715 ..._TYPE node with identical properties) and then install X
1716 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
1718 The whole point here is to end up with a situation where each
1719 and every ..._TYPE node the compiler creates will be uniquely
1720 associated with AT MOST one node representing a typedef name.
1721 This way, even though the compiler substitutes corresponding
1722 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
1723 early on, later parts of the compiler can always do the reverse
1724 translation and get back the corresponding typedef name. For
1725 example, given:
1727 typedef struct S MY_TYPE;
1728 MY_TYPE object;
1730 Later parts of the compiler might only know that `object' was of
1731 type `struct S' if it were not for code just below. With this
1732 code however, later parts of the compiler see something like:
1734 struct S' == struct S
1735 typedef struct S' MY_TYPE;
1736 struct S' object;
1738 And they can then deduce (from the node for type struct S') that
1739 the original object declaration was:
1741 MY_TYPE object;
1743 Being able to do this is important for proper support of protoize,
1744 and also for generating precise symbolic debugging information
1745 which takes full account of the programmer's (typedef) vocabulary.
1747 Obviously, we don't want to generate a duplicate ..._TYPE node if
1748 the TYPE_DECL node that we are now processing really represents a
1749 standard built-in type.
1751 Since all standard types are effectively declared at line zero
1752 in the source file, we can easily check to see if we are working
1753 on a standard type by checking the current value of lineno. */
1755 static void
1756 clone_underlying_type (tree x)
1758 if (DECL_IS_BUILTIN (x))
1760 if (TYPE_NAME (TREE_TYPE (x)) == 0)
1761 TYPE_NAME (TREE_TYPE (x)) = x;
1763 else if (TREE_TYPE (x) != error_mark_node
1764 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
1766 tree tt = TREE_TYPE (x);
1767 DECL_ORIGINAL_TYPE (x) = tt;
1768 tt = build_type_copy (tt);
1769 TYPE_NAME (tt) = x;
1770 TREE_USED (tt) = TREE_USED (x);
1771 TREE_TYPE (x) = tt;
1775 /* Record a decl-node X as belonging to the current lexical scope.
1776 Check for errors (such as an incompatible declaration for the same
1777 name already seen in the same scope).
1779 Returns either X or an old decl for the same name.
1780 If an old decl is returned, it may have been smashed
1781 to agree with what X says. */
1783 tree
1784 pushdecl (tree x)
1786 tree name = DECL_NAME (x);
1787 struct c_scope *scope = current_scope;
1788 struct c_binding *b;
1790 /* Functions need the lang_decl data. */
1791 if (TREE_CODE (x) == FUNCTION_DECL && ! DECL_LANG_SPECIFIC (x))
1792 DECL_LANG_SPECIFIC (x) = ggc_alloc_cleared (sizeof (struct lang_decl));
1794 /* Must set DECL_CONTEXT for everything not at file scope or
1795 DECL_FILE_SCOPE_P won't work. Local externs don't count
1796 unless they have initializers (which generate code). */
1797 if (current_function_decl
1798 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
1799 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
1800 DECL_CONTEXT (x) = current_function_decl;
1802 /* Anonymous decls are just inserted in the scope. */
1803 if (!name)
1805 bind (name, x, scope);
1806 return x;
1809 /* First, see if there is another declaration with the same name in
1810 the current scope. If there is, duplicate_decls may do all the
1811 work for us. If duplicate_decls returns false, that indicates
1812 two incompatible decls in the same scope; we are to silently
1813 replace the old one (duplicate_decls has issued all appropriate
1814 diagnostics). In particular, we should not consider possible
1815 duplicates in the external scope, or shadowing. */
1816 b = I_SYMBOL_BINDING (name);
1817 if (b && b->contour == scope)
1819 if (duplicate_decls (x, b->decl))
1820 return b->decl;
1821 else
1822 goto skip_external_and_shadow_checks;
1825 /* All declarations with external linkage, and all external
1826 references, go in the external scope, no matter what scope is
1827 current. However, the binding in that scope is ignored for
1828 purposes of normal name lookup. A separate binding structure is
1829 created in the requested scope; this governs the normal
1830 visibility of the symbol.
1832 The binding in the externals scope is used exclusively for
1833 detecting duplicate declarations of the same object, no matter
1834 what scope they are in; this is what we do here. (C99 6.2.7p2:
1835 All declarations that refer to the same object or function shall
1836 have compatible type; otherwise, the behavior is undefined.) */
1837 if (DECL_EXTERNAL (x) || scope == file_scope)
1839 if (warn_nested_externs
1840 && scope != file_scope
1841 && !DECL_IN_SYSTEM_HEADER (x))
1842 warning ("nested extern declaration of `%s'",
1843 IDENTIFIER_POINTER (name));
1845 while (b && b->contour != external_scope)
1846 b = b->shadowed;
1848 /* The point of the same_translation_unit_p check here is,
1849 we want to detect a duplicate decl for a construct like
1850 foo() { extern bar(); } ... static bar(); but not if
1851 they are in different translation units. In any case,
1852 the static does not go in the externals scope. */
1853 if (b
1854 && (DECL_EXTERNAL (x) || TREE_PUBLIC (x)
1855 || same_translation_unit_p (x, b->decl))
1856 && duplicate_decls (x, b->decl))
1858 bind (name, b->decl, scope);
1859 return b->decl;
1861 else if (DECL_EXTERNAL (x) || TREE_PUBLIC (x))
1863 C_DECL_IN_EXTERNAL_SCOPE (x) = 1;
1864 bind (name, x, external_scope);
1868 warn_if_shadowing (x);
1870 skip_external_and_shadow_checks:
1871 if (TREE_CODE (x) == TYPE_DECL)
1872 clone_underlying_type (x);
1874 bind (name, x, scope);
1876 /* If x's type is incomplete because it's based on a
1877 structure or union which has not yet been fully declared,
1878 attach it to that structure or union type, so we can go
1879 back and complete the variable declaration later, if the
1880 structure or union gets fully declared.
1882 If the input is erroneous, we can have error_mark in the type
1883 slot (e.g. "f(void a, ...)") - that doesn't count as an
1884 incomplete type. */
1885 if (TREE_TYPE (x) != error_mark_node
1886 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
1888 tree element = TREE_TYPE (x);
1890 while (TREE_CODE (element) == ARRAY_TYPE)
1891 element = TREE_TYPE (element);
1892 element = TYPE_MAIN_VARIANT (element);
1894 if ((TREE_CODE (element) == RECORD_TYPE
1895 || TREE_CODE (element) == UNION_TYPE)
1896 && (TREE_CODE (x) != TYPE_DECL
1897 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
1898 && !COMPLETE_TYPE_P (element))
1899 C_TYPE_INCOMPLETE_VARS (element)
1900 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
1902 return x;
1905 /* Record X as belonging to file scope.
1906 This is used only internally by the Objective-C front end,
1907 and is limited to its needs. duplicate_decls is not called;
1908 if there is any preexisting decl for this identifier, it is an ICE. */
1910 tree
1911 pushdecl_top_level (tree x)
1913 tree name;
1915 if (TREE_CODE (x) != VAR_DECL)
1916 abort ();
1918 name = DECL_NAME (x);
1920 if (I_SYMBOL_BINDING (name))
1921 abort ();
1923 if (DECL_EXTERNAL (x) || TREE_PUBLIC (x))
1925 C_DECL_IN_EXTERNAL_SCOPE (x) = 1;
1926 bind (name, x, external_scope);
1928 if (file_scope)
1929 bind (name, x, file_scope);
1931 return x;
1934 static void
1935 implicit_decl_warning (tree id, tree olddecl)
1937 void (*diag) (const char *, ...);
1938 switch (mesg_implicit_function_declaration)
1940 case 0: return;
1941 case 1: diag = warning; break;
1942 case 2: diag = error; break;
1943 default: abort ();
1946 diag (N_("implicit declaration of function '%E'"), id);
1947 if (olddecl)
1948 locate_old_decl (olddecl, diag);
1951 /* Generate an implicit declaration for identifier FUNCTIONID as a
1952 function of type int (). */
1954 tree
1955 implicitly_declare (tree functionid)
1957 tree decl = lookup_name_in_scope (functionid, external_scope);
1959 if (decl)
1961 /* FIXME: Objective-C has weird not-really-builtin functions
1962 which are supposed to be visible automatically. They wind up
1963 in the external scope because they're pushed before the file
1964 scope gets created. Catch this here and rebind them into the
1965 file scope. */
1966 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
1968 bind (functionid, decl, file_scope);
1969 return decl;
1971 else
1973 /* Implicit declaration of a function already declared
1974 (somehow) in a different scope, or as a built-in.
1975 If this is the first time this has happened, warn;
1976 then recycle the old declaration. */
1977 if (!C_DECL_IMPLICIT (decl))
1979 implicit_decl_warning (functionid, decl);
1980 C_DECL_IMPLICIT (decl) = 1;
1982 bind (functionid, decl, current_scope);
1983 return decl;
1987 /* Not seen before. */
1988 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
1989 DECL_EXTERNAL (decl) = 1;
1990 TREE_PUBLIC (decl) = 1;
1991 C_DECL_IMPLICIT (decl) = 1;
1992 implicit_decl_warning (functionid, 0);
1994 /* C89 says implicit declarations are in the innermost block.
1995 So we record the decl in the standard fashion. */
1996 decl = pushdecl (decl);
1998 /* No need to call objc_check_decl here - it's a function type. */
1999 rest_of_decl_compilation (decl, NULL, 0, 0);
2001 /* Write a record describing this implicit function declaration
2002 to the prototypes file (if requested). */
2003 gen_aux_info_record (decl, 0, 1, 0);
2005 /* Possibly apply some default attributes to this implicit declaration. */
2006 decl_attributes (&decl, NULL_TREE, 0);
2008 return decl;
2011 /* Issue an error message for a reference to an undeclared variable
2012 ID, including a reference to a builtin outside of function-call
2013 context. Establish a binding of the identifier to error_mark_node
2014 in an appropriate scope, which will suppress further errors for the
2015 same identifier. */
2016 void
2017 undeclared_variable (tree id)
2019 static bool already = false;
2020 struct c_scope *scope;
2022 if (current_function_decl == 0)
2024 error ("'%E' undeclared here (not in a function)", id);
2025 scope = current_scope;
2027 else
2029 error ("'%E' undeclared (first use in this function)", id);
2031 if (! already)
2033 error ("(Each undeclared identifier is reported only once");
2034 error ("for each function it appears in.)");
2035 already = true;
2038 /* If we are parsing old-style parameter decls, current_function_decl
2039 will be nonnull but current_function_scope will be null. */
2040 scope = current_function_scope ? current_function_scope : current_scope;
2042 bind (id, error_mark_node, scope);
2045 /* Subroutine of lookup_label, declare_label, define_label: construct a
2046 LABEL_DECL with all the proper frills. */
2048 static tree
2049 make_label (tree name, location_t location)
2051 tree label = build_decl (LABEL_DECL, name, void_type_node);
2053 DECL_CONTEXT (label) = current_function_decl;
2054 DECL_MODE (label) = VOIDmode;
2055 DECL_SOURCE_LOCATION (label) = location;
2057 return label;
2060 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2061 Create one if none exists so far for the current function.
2062 This is called when a label is used in a goto expression or
2063 has its address taken. */
2065 tree
2066 lookup_label (tree name)
2068 tree label;
2070 if (current_function_decl == 0)
2072 error ("label %s referenced outside of any function",
2073 IDENTIFIER_POINTER (name));
2074 return 0;
2077 /* Use a label already defined or ref'd with this name, but not if
2078 it is inherited from a containing function and wasn't declared
2079 using __label__. */
2080 label = I_LABEL_DECL (name);
2081 if (label && (DECL_CONTEXT (label) == current_function_decl
2082 || C_DECLARED_LABEL_FLAG (label)))
2084 /* If the label has only been declared, update its apparent
2085 location to point here, for better diagnostics if it
2086 turns out not to have been defined. */
2087 if (!TREE_USED (label))
2088 DECL_SOURCE_LOCATION (label) = input_location;
2089 return label;
2092 /* No label binding for that identifier; make one. */
2093 label = make_label (name, input_location);
2095 /* Ordinary labels go in the current function scope. */
2096 bind (name, label, current_function_scope);
2097 return label;
2100 /* Make a label named NAME in the current function, shadowing silently
2101 any that may be inherited from containing functions or containing
2102 scopes. This is called for __label__ declarations. */
2104 tree
2105 declare_label (tree name)
2107 struct c_binding *b = I_LABEL_BINDING (name);
2108 tree label;
2110 /* Check to make sure that the label hasn't already been declared
2111 at this scope */
2112 if (b && b->contour == current_scope)
2114 error ("duplicate label declaration `%s'", IDENTIFIER_POINTER (name));
2115 locate_old_decl (b->decl, error);
2117 /* Just use the previous declaration. */
2118 return b->decl;
2121 label = make_label (name, input_location);
2122 C_DECLARED_LABEL_FLAG (label) = 1;
2124 /* Declared labels go in the current scope. */
2125 bind (name, label, current_scope);
2126 return label;
2129 /* Define a label, specifying the location in the source file.
2130 Return the LABEL_DECL node for the label, if the definition is valid.
2131 Otherwise return 0. */
2133 tree
2134 define_label (location_t location, tree name)
2136 /* Find any preexisting label with this name. It is an error
2137 if that label has already been defined in this function, or
2138 if there is a containing function with a declared label with
2139 the same name. */
2140 tree label = I_LABEL_DECL (name);
2142 if (label
2143 && ((DECL_CONTEXT (label) == current_function_decl
2144 && DECL_INITIAL (label) != 0)
2145 || (DECL_CONTEXT (label) != current_function_decl
2146 && C_DECLARED_LABEL_FLAG (label))))
2148 error ("%Hduplicate label `%D'", &location, label);
2149 locate_old_decl (label, error);
2150 return 0;
2152 else if (label && DECL_CONTEXT (label) == current_function_decl)
2154 /* The label has been used or declared already in this function,
2155 but not defined. Update its location to point to this
2156 definition. */
2157 DECL_SOURCE_LOCATION (label) = location;
2159 else
2161 /* No label binding for that identifier; make one. */
2162 label = make_label (name, location);
2164 /* Ordinary labels go in the current function scope. */
2165 bind (name, label, current_function_scope);
2168 if (warn_traditional && !in_system_header && lookup_name (name))
2169 warning ("%Htraditional C lacks a separate namespace for labels, "
2170 "identifier `%s' conflicts", &location,
2171 IDENTIFIER_POINTER (name));
2173 /* Mark label as having been defined. */
2174 DECL_INITIAL (label) = error_mark_node;
2175 return label;
2178 /* Given NAME, an IDENTIFIER_NODE,
2179 return the structure (or union or enum) definition for that name.
2180 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2181 CODE says which kind of type the caller wants;
2182 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2183 If the wrong kind of type is found, an error is reported. */
2185 static tree
2186 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2188 struct c_binding *b = I_TAG_BINDING (name);
2189 int thislevel = 0;
2191 if (!b || !b->decl)
2192 return 0;
2194 /* We only care about whether it's in this level if
2195 thislevel_only was set or it might be a type clash. */
2196 if (thislevel_only || TREE_CODE (b->decl) != code)
2198 /* For our purposes, a tag in the external scope is the same as
2199 a tag in the file scope. (Primarily relevant to Objective-C
2200 and its builtin structure tags, which get pushed before the
2201 file scope is created.) */
2202 if (b->contour == current_scope
2203 || (current_scope == file_scope && b->contour == external_scope))
2204 thislevel = 1;
2207 if (thislevel_only && !thislevel)
2208 return 0;
2210 if (TREE_CODE (b->decl) != code)
2212 /* Definition isn't the kind we were looking for. */
2213 pending_invalid_xref = name;
2214 pending_invalid_xref_location = input_location;
2216 /* If in the same binding level as a declaration as a tag
2217 of a different type, this must not be allowed to
2218 shadow that tag, so give the error immediately.
2219 (For example, "struct foo; union foo;" is invalid.) */
2220 if (thislevel)
2221 pending_xref_error ();
2223 return b->decl;
2226 /* Print an error message now
2227 for a recent invalid struct, union or enum cross reference.
2228 We don't print them immediately because they are not invalid
2229 when used in the `struct foo;' construct for shadowing. */
2231 void
2232 pending_xref_error (void)
2234 if (pending_invalid_xref != 0)
2235 error ("%H`%s' defined as wrong kind of tag",
2236 &pending_invalid_xref_location,
2237 IDENTIFIER_POINTER (pending_invalid_xref));
2238 pending_invalid_xref = 0;
2242 /* Look up NAME in the current scope and its superiors
2243 in the namespace of variables, functions and typedefs.
2244 Return a ..._DECL node of some kind representing its definition,
2245 or return 0 if it is undefined. */
2247 tree
2248 lookup_name (tree name)
2250 struct c_binding *b = I_SYMBOL_BINDING (name);
2251 if (b && (b->contour != external_scope || TREE_CODE (b->decl) == TYPE_DECL))
2252 return b->decl;
2253 return 0;
2256 /* Similar to `lookup_name' but look only at the indicated scope. */
2258 static tree
2259 lookup_name_in_scope (tree name, struct c_scope *scope)
2261 struct c_binding *b;
2263 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2264 if (b->contour == scope)
2265 return b->decl;
2266 return 0;
2269 /* Create the predefined scalar types of C,
2270 and some nodes representing standard constants (0, 1, (void *) 0).
2271 Initialize the global scope.
2272 Make definitions for built-in primitive functions. */
2274 void
2275 c_init_decl_processing (void)
2277 tree endlink;
2278 tree ptr_ftype_void, ptr_ftype_ptr;
2279 location_t save_loc = input_location;
2281 /* Adds some ggc roots, and reserved words for c-parse.in. */
2282 c_parse_init ();
2284 current_function_decl = 0;
2286 /* Make the externals scope. */
2287 push_scope ();
2288 external_scope = current_scope;
2290 /* Declarations from c_common_nodes_and_builtins must not be associated
2291 with this input file, lest we get differences between using and not
2292 using preprocessed headers. */
2293 #ifdef USE_MAPPED_LOCATION
2294 input_location = BUILTINS_LOCATION;
2295 #else
2296 input_location.file = "<built-in>";
2297 input_location.line = 0;
2298 #endif
2300 build_common_tree_nodes (flag_signed_char);
2302 c_common_nodes_and_builtins ();
2304 /* In C, comparisons and TRUTH_* expressions have type int. */
2305 truthvalue_type_node = integer_type_node;
2306 truthvalue_true_node = integer_one_node;
2307 truthvalue_false_node = integer_zero_node;
2309 /* Even in C99, which has a real boolean type. */
2310 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2311 boolean_type_node));
2313 endlink = void_list_node;
2314 ptr_ftype_void = build_function_type (ptr_type_node, endlink);
2315 ptr_ftype_ptr
2316 = build_function_type (ptr_type_node,
2317 tree_cons (NULL_TREE, ptr_type_node, endlink));
2319 input_location = save_loc;
2321 pedantic_lvalues = true;
2323 make_fname_decl = c_make_fname_decl;
2324 start_fname_decls ();
2327 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2328 decl, NAME is the initialization string and TYPE_DEP indicates whether
2329 NAME depended on the type of the function. As we don't yet implement
2330 delayed emission of static data, we mark the decl as emitted
2331 so it is not placed in the output. Anything using it must therefore pull
2332 out the STRING_CST initializer directly. FIXME. */
2334 static tree
2335 c_make_fname_decl (tree id, int type_dep)
2337 const char *name = fname_as_string (type_dep);
2338 tree decl, type, init;
2339 size_t length = strlen (name);
2341 type = build_array_type
2342 (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
2343 build_index_type (size_int (length)));
2345 decl = build_decl (VAR_DECL, id, type);
2347 TREE_STATIC (decl) = 1;
2348 TREE_READONLY (decl) = 1;
2349 DECL_ARTIFICIAL (decl) = 1;
2351 init = build_string (length + 1, name);
2352 free ((char *) name);
2353 TREE_TYPE (init) = type;
2354 DECL_INITIAL (decl) = init;
2356 TREE_USED (decl) = 1;
2358 if (current_function_decl)
2360 DECL_CONTEXT (decl) = current_function_decl;
2361 bind (id, decl, current_function_scope);
2364 finish_decl (decl, init, NULL_TREE);
2366 return decl;
2369 /* Return a definition for a builtin function named NAME and whose data type
2370 is TYPE. TYPE should be a function type with argument types.
2371 FUNCTION_CODE tells later passes how to compile calls to this function.
2372 See tree.h for its possible values.
2374 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
2375 the name to be called if we can't opencode the function. If
2376 ATTRS is nonzero, use that for the function's attribute list. */
2378 tree
2379 builtin_function (const char *name, tree type, int function_code,
2380 enum built_in_class class, const char *library_name,
2381 tree attrs)
2383 tree id = get_identifier (name);
2384 tree decl = build_decl (FUNCTION_DECL, id, type);
2385 TREE_PUBLIC (decl) = 1;
2386 DECL_EXTERNAL (decl) = 1;
2387 DECL_LANG_SPECIFIC (decl) = ggc_alloc_cleared (sizeof (struct lang_decl));
2388 DECL_BUILT_IN_CLASS (decl) = class;
2389 DECL_FUNCTION_CODE (decl) = function_code;
2390 if (library_name)
2391 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
2393 /* Should never be called on a symbol with a preexisting meaning. */
2394 if (I_SYMBOL_BINDING (id))
2395 abort ();
2397 C_DECL_IN_EXTERNAL_SCOPE (decl) = 1;
2398 bind (id, decl, external_scope);
2400 /* Builtins in the implementation namespace are made visible without
2401 needing to be explicitly declared. See push_file_scope. */
2402 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2404 TREE_CHAIN (decl) = visible_builtins;
2405 visible_builtins = decl;
2408 /* Possibly apply some default attributes to this built-in function. */
2409 if (attrs)
2410 decl_attributes (&decl, attrs, ATTR_FLAG_BUILT_IN);
2411 else
2412 decl_attributes (&decl, NULL_TREE, 0);
2414 return decl;
2417 /* Called when a declaration is seen that contains no names to declare.
2418 If its type is a reference to a structure, union or enum inherited
2419 from a containing scope, shadow that tag name for the current scope
2420 with a forward reference.
2421 If its type defines a new named structure or union
2422 or defines an enum, it is valid but we need not do anything here.
2423 Otherwise, it is an error. */
2425 void
2426 shadow_tag (tree declspecs)
2428 shadow_tag_warned (declspecs, 0);
2431 void
2432 shadow_tag_warned (tree declspecs, int warned)
2435 /* 1 => we have done a pedwarn. 2 => we have done a warning, but
2436 no pedwarn. */
2438 int found_tag = 0;
2439 tree link;
2440 tree specs, attrs;
2442 pending_invalid_xref = 0;
2444 /* Remove the attributes from declspecs, since they will confuse the
2445 following code. */
2446 split_specs_attrs (declspecs, &specs, &attrs);
2448 for (link = specs; link; link = TREE_CHAIN (link))
2450 tree value = TREE_VALUE (link);
2451 enum tree_code code = TREE_CODE (value);
2453 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2454 /* Used to test also that TYPE_SIZE (value) != 0.
2455 That caused warning for `struct foo;' at top level in the file. */
2457 tree name = TYPE_NAME (value);
2458 tree t;
2460 found_tag++;
2462 if (name == 0)
2464 if (warned != 1 && code != ENUMERAL_TYPE)
2465 /* Empty unnamed enum OK */
2467 pedwarn ("unnamed struct/union that defines no instances");
2468 warned = 1;
2471 else
2473 t = lookup_tag (code, name, 1);
2475 if (t == 0)
2477 t = make_node (code);
2478 pushtag (name, t);
2482 else
2484 if (!warned && ! in_system_header)
2486 warning ("useless keyword or type name in empty declaration");
2487 warned = 2;
2492 if (found_tag > 1)
2493 error ("two types specified in one empty declaration");
2495 if (warned != 1)
2497 if (found_tag == 0)
2498 pedwarn ("empty declaration");
2502 /* Construct an array declarator. EXPR is the expression inside [], or
2503 NULL_TREE. QUALS are the type qualifiers inside the [] (to be applied
2504 to the pointer to which a parameter array is converted). STATIC_P is
2505 nonzero if "static" is inside the [], zero otherwise. VLA_UNSPEC_P
2506 is nonzero is the array is [*], a VLA of unspecified length which is
2507 nevertheless a complete type (not currently implemented by GCC),
2508 zero otherwise. The declarator is constructed as an ARRAY_REF
2509 (to be decoded by grokdeclarator), whose operand 0 is what's on the
2510 left of the [] (filled by in set_array_declarator_type) and operand 1
2511 is the expression inside; whose TREE_TYPE is the type qualifiers and
2512 which has TREE_STATIC set if "static" is used. */
2514 tree
2515 build_array_declarator (tree expr, tree quals, int static_p, int vla_unspec_p)
2517 tree decl;
2518 decl = build_nt (ARRAY_REF, NULL_TREE, expr, NULL_TREE, NULL_TREE);
2519 TREE_TYPE (decl) = quals;
2520 TREE_STATIC (decl) = (static_p ? 1 : 0);
2521 if (pedantic && !flag_isoc99)
2523 if (static_p || quals != NULL_TREE)
2524 pedwarn ("ISO C90 does not support `static' or type qualifiers in parameter array declarators");
2525 if (vla_unspec_p)
2526 pedwarn ("ISO C90 does not support `[*]' array declarators");
2528 if (vla_unspec_p)
2529 warning ("GCC does not yet properly implement `[*]' array declarators");
2530 return decl;
2533 /* Set the type of an array declarator. DECL is the declarator, as
2534 constructed by build_array_declarator; TYPE is what appears on the left
2535 of the [] and goes in operand 0. ABSTRACT_P is nonzero if it is an
2536 abstract declarator, zero otherwise; this is used to reject static and
2537 type qualifiers in abstract declarators, where they are not in the
2538 C99 grammar. */
2540 tree
2541 set_array_declarator_type (tree decl, tree type, int abstract_p)
2543 TREE_OPERAND (decl, 0) = type;
2544 if (abstract_p && (TREE_TYPE (decl) != NULL_TREE || TREE_STATIC (decl)))
2545 error ("static or type qualifiers in abstract declarator");
2546 return decl;
2549 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
2551 tree
2552 groktypename (tree typename)
2554 tree specs, attrs;
2556 if (TREE_CODE (typename) != TREE_LIST)
2557 return typename;
2559 split_specs_attrs (TREE_PURPOSE (typename), &specs, &attrs);
2561 typename = grokdeclarator (TREE_VALUE (typename), specs, TYPENAME, 0,
2562 NULL);
2564 /* Apply attributes. */
2565 decl_attributes (&typename, attrs, 0);
2567 return typename;
2570 /* Return a PARM_DECL node for a given pair of specs and declarator. */
2572 tree
2573 groktypename_in_parm_context (tree typename)
2575 if (TREE_CODE (typename) != TREE_LIST)
2576 return typename;
2577 return grokdeclarator (TREE_VALUE (typename),
2578 TREE_PURPOSE (typename),
2579 PARM, 0, NULL);
2582 /* Decode a declarator in an ordinary declaration or data definition.
2583 This is called as soon as the type information and variable name
2584 have been parsed, before parsing the initializer if any.
2585 Here we create the ..._DECL node, fill in its type,
2586 and put it on the list of decls for the current context.
2587 The ..._DECL node is returned as the value.
2589 Exception: for arrays where the length is not specified,
2590 the type is left null, to be filled in by `finish_decl'.
2592 Function definitions do not come here; they go to start_function
2593 instead. However, external and forward declarations of functions
2594 do go through here. Structure field declarations are done by
2595 grokfield and not through here. */
2597 tree
2598 start_decl (tree declarator, tree declspecs, int initialized, tree attributes)
2600 tree decl;
2601 tree tem;
2603 /* An object declared as __attribute__((deprecated)) suppresses
2604 warnings of uses of other deprecated items. */
2605 if (lookup_attribute ("deprecated", attributes))
2606 deprecated_state = DEPRECATED_SUPPRESS;
2608 decl = grokdeclarator (declarator, declspecs,
2609 NORMAL, initialized, NULL);
2611 deprecated_state = DEPRECATED_NORMAL;
2613 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
2614 && MAIN_NAME_P (DECL_NAME (decl)))
2615 warning ("%J'%D' is usually a function", decl, decl);
2617 if (initialized)
2618 /* Is it valid for this decl to have an initializer at all?
2619 If not, set INITIALIZED to zero, which will indirectly
2620 tell 'finish_decl' to ignore the initializer once it is parsed. */
2621 switch (TREE_CODE (decl))
2623 case TYPE_DECL:
2624 error ("typedef '%D' is initialized (use __typeof__ instead)", decl);
2625 initialized = 0;
2626 break;
2628 case FUNCTION_DECL:
2629 error ("function '%D' is initialized like a variable", decl);
2630 initialized = 0;
2631 break;
2633 case PARM_DECL:
2634 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
2635 error ("parameter '%D' is initialized", decl);
2636 initialized = 0;
2637 break;
2639 default:
2640 /* Don't allow initializations for incomplete types except for
2641 arrays which might be completed by the initialization. */
2643 /* This can happen if the array size is an undefined macro.
2644 We already gave a warning, so we don't need another one. */
2645 if (TREE_TYPE (decl) == error_mark_node)
2646 initialized = 0;
2647 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
2649 /* A complete type is ok if size is fixed. */
2651 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
2652 || C_DECL_VARIABLE_SIZE (decl))
2654 error ("variable-sized object may not be initialized");
2655 initialized = 0;
2658 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
2660 error ("variable '%D' has initializer but incomplete type", decl);
2661 initialized = 0;
2663 else if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
2665 error ("elements of array '%D' have incomplete type", decl);
2666 initialized = 0;
2670 if (initialized)
2672 DECL_EXTERNAL (decl) = 0;
2673 if (current_scope == file_scope)
2674 TREE_STATIC (decl) = 1;
2676 /* Tell 'pushdecl' this is an initialized decl
2677 even though we don't yet have the initializer expression.
2678 Also tell 'finish_decl' it may store the real initializer. */
2679 DECL_INITIAL (decl) = error_mark_node;
2682 /* If this is a function declaration, write a record describing it to the
2683 prototypes file (if requested). */
2685 if (TREE_CODE (decl) == FUNCTION_DECL)
2686 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
2688 /* ANSI specifies that a tentative definition which is not merged with
2689 a non-tentative definition behaves exactly like a definition with an
2690 initializer equal to zero. (Section 3.7.2)
2692 -fno-common gives strict ANSI behavior, though this tends to break
2693 a large body of code that grew up without this rule.
2695 Thread-local variables are never common, since there's no entrenched
2696 body of code to break, and it allows more efficient variable references
2697 in the presence of dynamic linking. */
2699 if (TREE_CODE (decl) == VAR_DECL
2700 && !initialized
2701 && TREE_PUBLIC (decl)
2702 && !DECL_THREAD_LOCAL (decl)
2703 && !flag_no_common)
2704 DECL_COMMON (decl) = 1;
2706 /* Set attributes here so if duplicate decl, will have proper attributes. */
2707 decl_attributes (&decl, attributes, 0);
2709 if (TREE_CODE (decl) == FUNCTION_DECL
2710 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
2712 tree ce = declarator;
2714 if (TREE_CODE (ce) == INDIRECT_REF)
2715 ce = TREE_OPERAND (declarator, 0);
2716 if (TREE_CODE (ce) == CALL_EXPR)
2718 tree args = TREE_PURPOSE (TREE_OPERAND (ce, 1));
2719 for (; args; args = TREE_CHAIN (args))
2721 tree type = TREE_TYPE (args);
2722 if (type && INTEGRAL_TYPE_P (type)
2723 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
2724 DECL_ARG_TYPE (args) = integer_type_node;
2729 if (TREE_CODE (decl) == FUNCTION_DECL
2730 && DECL_DECLARED_INLINE_P (decl)
2731 && DECL_UNINLINABLE (decl)
2732 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
2733 warning ("%Jinline function '%D' given attribute noinline", decl, decl);
2735 /* Add this decl to the current scope.
2736 TEM may equal DECL or it may be a previous decl of the same name. */
2737 tem = pushdecl (decl);
2739 return tem;
2742 /* Finish processing of a declaration;
2743 install its initial value.
2744 If the length of an array type is not known before,
2745 it must be determined now, from the initial value, or it is an error. */
2747 void
2748 finish_decl (tree decl, tree init, tree asmspec_tree)
2750 tree type = TREE_TYPE (decl);
2751 int was_incomplete = (DECL_SIZE (decl) == 0);
2752 const char *asmspec = 0;
2754 /* If a name was specified, get the string. */
2755 if (current_scope == file_scope)
2756 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
2757 if (asmspec_tree)
2758 asmspec = TREE_STRING_POINTER (asmspec_tree);
2760 /* If `start_decl' didn't like having an initialization, ignore it now. */
2761 if (init != 0 && DECL_INITIAL (decl) == 0)
2762 init = 0;
2764 /* Don't crash if parm is initialized. */
2765 if (TREE_CODE (decl) == PARM_DECL)
2766 init = 0;
2768 if (init)
2769 store_init_value (decl, init);
2771 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
2772 || TREE_CODE (decl) == FUNCTION_DECL
2773 || TREE_CODE (decl) == FIELD_DECL))
2774 objc_check_decl (decl);
2776 /* Deduce size of array from initialization, if not already known. */
2777 if (TREE_CODE (type) == ARRAY_TYPE
2778 && TYPE_DOMAIN (type) == 0
2779 && TREE_CODE (decl) != TYPE_DECL)
2781 int do_default
2782 = (TREE_STATIC (decl)
2783 /* Even if pedantic, an external linkage array
2784 may have incomplete type at first. */
2785 ? pedantic && !TREE_PUBLIC (decl)
2786 : !DECL_EXTERNAL (decl));
2787 int failure
2788 = complete_array_type (type, DECL_INITIAL (decl), do_default);
2790 /* Get the completed type made by complete_array_type. */
2791 type = TREE_TYPE (decl);
2793 if (failure == 1)
2794 error ("%Jinitializer fails to determine size of '%D'", decl, decl);
2796 else if (failure == 2)
2798 if (do_default)
2799 error ("%Jarray size missing in '%D'", decl, decl);
2800 /* If a `static' var's size isn't known,
2801 make it extern as well as static, so it does not get
2802 allocated.
2803 If it is not `static', then do not mark extern;
2804 finish_incomplete_decl will give it a default size
2805 and it will get allocated. */
2806 else if (!pedantic && TREE_STATIC (decl) && ! TREE_PUBLIC (decl))
2807 DECL_EXTERNAL (decl) = 1;
2810 /* TYPE_MAX_VALUE is always one less than the number of elements
2811 in the array, because we start counting at zero. Therefore,
2812 warn only if the value is less than zero. */
2813 else if (pedantic && TYPE_DOMAIN (type) != 0
2814 && tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) < 0)
2815 error ("%Jzero or negative size array '%D'", decl, decl);
2817 layout_decl (decl, 0);
2820 if (TREE_CODE (decl) == VAR_DECL)
2822 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
2823 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
2824 layout_decl (decl, 0);
2826 if (DECL_SIZE (decl) == 0
2827 /* Don't give an error if we already gave one earlier. */
2828 && TREE_TYPE (decl) != error_mark_node
2829 && (TREE_STATIC (decl)
2831 /* A static variable with an incomplete type
2832 is an error if it is initialized.
2833 Also if it is not file scope.
2834 Otherwise, let it through, but if it is not `extern'
2835 then it may cause an error message later. */
2836 (DECL_INITIAL (decl) != 0
2837 || !DECL_FILE_SCOPE_P (decl))
2839 /* An automatic variable with an incomplete type
2840 is an error. */
2841 !DECL_EXTERNAL (decl)))
2843 error ("%Jstorage size of '%D' isn't known", decl, decl);
2844 TREE_TYPE (decl) = error_mark_node;
2847 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
2848 && DECL_SIZE (decl) != 0)
2850 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
2851 constant_expression_warning (DECL_SIZE (decl));
2852 else
2853 error ("%Jstorage size of '%D' isn't constant", decl, decl);
2856 if (TREE_USED (type))
2857 TREE_USED (decl) = 1;
2860 /* If this is a function and an assembler name is specified, reset DECL_RTL
2861 so we can give it its new name. Also, update built_in_decls if it
2862 was a normal built-in. */
2863 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
2865 /* ASMSPEC is given, and not the name of a register. Mark the
2866 name with a star so assemble_name won't munge it. */
2867 char *starred = alloca (strlen (asmspec) + 2);
2868 starred[0] = '*';
2869 strcpy (starred + 1, asmspec);
2871 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
2873 tree builtin = built_in_decls [DECL_FUNCTION_CODE (decl)];
2874 SET_DECL_RTL (builtin, NULL_RTX);
2875 change_decl_assembler_name (builtin, get_identifier (starred));
2876 #ifdef TARGET_MEM_FUNCTIONS
2877 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMCPY)
2878 init_block_move_fn (starred);
2879 else if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMSET)
2880 init_block_clear_fn (starred);
2881 #else
2882 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_BCOPY)
2883 init_block_move_fn (starred);
2884 else if (DECL_FUNCTION_CODE (decl) == BUILT_IN_BZERO)
2885 init_block_clear_fn (starred);
2886 #endif
2888 SET_DECL_RTL (decl, NULL_RTX);
2889 change_decl_assembler_name (decl, get_identifier (starred));
2892 /* If #pragma weak was used, mark the decl weak now. */
2893 if (current_scope == file_scope)
2894 maybe_apply_pragma_weak (decl);
2896 /* Output the assembler code and/or RTL code for variables and functions,
2897 unless the type is an undefined structure or union.
2898 If not, it will get done when the type is completed. */
2900 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
2902 /* This is a no-op in c-lang.c or something real in objc-act.c. */
2903 if (c_dialect_objc ())
2904 objc_check_decl (decl);
2906 if (DECL_FILE_SCOPE_P (decl))
2908 if (DECL_INITIAL (decl) == NULL_TREE
2909 || DECL_INITIAL (decl) == error_mark_node)
2910 /* Don't output anything
2911 when a tentative file-scope definition is seen.
2912 But at end of compilation, do output code for them. */
2913 DECL_DEFER_OUTPUT (decl) = 1;
2914 rest_of_decl_compilation (decl, asmspec, true, 0);
2916 else
2918 /* This is a local variable. If there is an ASMSPEC, the
2919 user has requested that we handle it specially. */
2920 if (asmspec)
2922 /* In conjunction with an ASMSPEC, the `register'
2923 keyword indicates that we should place the variable
2924 in a particular register. */
2925 if (C_DECL_REGISTER (decl))
2927 DECL_HARD_REGISTER (decl) = 1;
2928 /* This cannot be done for a structure with volatile
2929 fields, on which DECL_REGISTER will have been
2930 reset. */
2931 if (!DECL_REGISTER (decl))
2932 error ("cannot put object with volatile field into register");
2935 /* If this is not a static variable, issue a warning.
2936 It doesn't make any sense to give an ASMSPEC for an
2937 ordinary, non-register local variable. Historically,
2938 GCC has accepted -- but ignored -- the ASMSPEC in
2939 this case. */
2940 if (TREE_CODE (decl) == VAR_DECL
2941 && !C_DECL_REGISTER (decl)
2942 && !TREE_STATIC (decl))
2943 warning ("%Jignoring asm-specifier for non-static local "
2944 "variable '%D'", decl, decl);
2945 else
2946 change_decl_assembler_name (decl, get_identifier (asmspec));
2949 if (TREE_CODE (decl) != FUNCTION_DECL)
2950 add_stmt (build_stmt (DECL_EXPR, decl));
2953 if (!DECL_FILE_SCOPE_P (decl))
2955 /* Recompute the RTL of a local array now
2956 if it used to be an incomplete type. */
2957 if (was_incomplete
2958 && ! TREE_STATIC (decl) && ! DECL_EXTERNAL (decl))
2960 /* If we used it already as memory, it must stay in memory. */
2961 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
2962 /* If it's still incomplete now, no init will save it. */
2963 if (DECL_SIZE (decl) == 0)
2964 DECL_INITIAL (decl) = 0;
2969 /* If this was marked 'used', be sure it will be output. */
2970 if (lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
2971 mark_decl_referenced (decl);
2973 if (TREE_CODE (decl) == TYPE_DECL)
2975 if (!DECL_FILE_SCOPE_P (decl)
2976 && variably_modified_type_p (TREE_TYPE (decl)))
2977 add_stmt (build_stmt (DECL_EXPR, decl));
2979 rest_of_decl_compilation (decl, NULL, DECL_FILE_SCOPE_P (decl), 0);
2982 /* At the end of a declaration, throw away any variable type sizes
2983 of types defined inside that declaration. There is no use
2984 computing them in the following function definition. */
2985 if (current_scope == file_scope)
2986 get_pending_sizes ();
2988 /* Install a cleanup (aka destructor) if one was given. */
2989 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
2991 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
2992 if (attr)
2994 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
2995 tree cleanup_decl = lookup_name (cleanup_id);
2996 tree cleanup;
2998 /* Build "cleanup(&decl)" for the destructor. */
2999 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3000 cleanup = build_tree_list (NULL_TREE, cleanup);
3001 cleanup = build_function_call (cleanup_decl, cleanup);
3003 /* Don't warn about decl unused; the cleanup uses it. */
3004 TREE_USED (decl) = 1;
3005 TREE_USED (cleanup_decl) = 1;
3007 /* Initialize EH, if we've been told to do so. */
3008 if (flag_exceptions && !c_eh_initialized_p)
3010 c_eh_initialized_p = true;
3011 eh_personality_libfunc
3012 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3013 ? "__gcc_personality_sj0"
3014 : "__gcc_personality_v0");
3015 using_eh_for_cleanups ();
3018 push_cleanup (decl, cleanup, false);
3023 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3024 and push that on the current scope. */
3026 void
3027 push_parm_decl (tree parm)
3029 tree decl;
3031 decl = grokdeclarator (TREE_VALUE (TREE_PURPOSE (parm)),
3032 TREE_PURPOSE (TREE_PURPOSE (parm)),
3033 PARM, 0, NULL);
3034 decl_attributes (&decl, TREE_VALUE (parm), 0);
3036 decl = pushdecl (decl);
3038 finish_decl (decl, NULL_TREE, NULL_TREE);
3041 /* Mark all the parameter declarations to date as forward decls.
3042 Also diagnose use of this extension. */
3044 void
3045 mark_forward_parm_decls (void)
3047 struct c_binding *b;
3049 if (pedantic && !current_scope->warned_forward_parm_decls)
3051 pedwarn ("ISO C forbids forward parameter declarations");
3052 current_scope->warned_forward_parm_decls = true;
3055 for (b = current_scope->bindings; b; b = b->prev)
3056 if (TREE_CODE (b->decl) == PARM_DECL)
3057 TREE_ASM_WRITTEN (b->decl) = 1;
3060 static GTY(()) int compound_literal_number;
3062 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3063 literal, which may be an incomplete array type completed by the
3064 initializer; INIT is a CONSTRUCTOR that initializes the compound
3065 literal. */
3067 tree
3068 build_compound_literal (tree type, tree init)
3070 /* We do not use start_decl here because we have a type, not a declarator;
3071 and do not use finish_decl because the decl should be stored inside
3072 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3073 tree decl = build_decl (VAR_DECL, NULL_TREE, type);
3074 tree complit;
3075 tree stmt;
3076 DECL_EXTERNAL (decl) = 0;
3077 TREE_PUBLIC (decl) = 0;
3078 TREE_STATIC (decl) = (current_scope == file_scope);
3079 DECL_CONTEXT (decl) = current_function_decl;
3080 TREE_USED (decl) = 1;
3081 TREE_TYPE (decl) = type;
3082 TREE_READONLY (decl) = TYPE_READONLY (type);
3083 store_init_value (decl, init);
3085 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3087 int failure = complete_array_type (type, DECL_INITIAL (decl), 1);
3088 if (failure)
3089 abort ();
3092 type = TREE_TYPE (decl);
3093 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3094 return error_mark_node;
3096 stmt = build_stmt (DECL_EXPR, decl);
3097 complit = build1 (COMPOUND_LITERAL_EXPR, TREE_TYPE (decl), stmt);
3098 TREE_SIDE_EFFECTS (complit) = 1;
3100 layout_decl (decl, 0);
3102 if (TREE_STATIC (decl))
3104 /* This decl needs a name for the assembler output. We also need
3105 a unique suffix to be added to the name. */
3106 char *name;
3108 ASM_FORMAT_PRIVATE_NAME (name, "__compound_literal",
3109 compound_literal_number);
3110 compound_literal_number++;
3111 DECL_NAME (decl) = get_identifier (name);
3112 DECL_DEFER_OUTPUT (decl) = 1;
3113 DECL_COMDAT (decl) = 1;
3114 DECL_ARTIFICIAL (decl) = 1;
3115 pushdecl (decl);
3116 rest_of_decl_compilation (decl, NULL, 1, 0);
3119 return complit;
3122 /* Make TYPE a complete type based on INITIAL_VALUE.
3123 Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
3124 2 if there was no information (in which case assume 1 if DO_DEFAULT). */
3127 complete_array_type (tree type, tree initial_value, int do_default)
3129 tree maxindex = NULL_TREE;
3130 int value = 0;
3132 if (initial_value)
3134 /* Note MAXINDEX is really the maximum index,
3135 one less than the size. */
3136 if (TREE_CODE (initial_value) == STRING_CST)
3138 int eltsize
3139 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
3140 maxindex = build_int_2 ((TREE_STRING_LENGTH (initial_value)
3141 / eltsize) - 1, 0);
3143 else if (TREE_CODE (initial_value) == CONSTRUCTOR)
3145 tree elts = CONSTRUCTOR_ELTS (initial_value);
3146 maxindex = build_int_2 (-1, -1);
3147 for (; elts; elts = TREE_CHAIN (elts))
3149 if (TREE_PURPOSE (elts))
3150 maxindex = TREE_PURPOSE (elts);
3151 else
3152 maxindex = fold (build (PLUS_EXPR, integer_type_node,
3153 maxindex, integer_one_node));
3155 maxindex = copy_node (maxindex);
3157 else
3159 /* Make an error message unless that happened already. */
3160 if (initial_value != error_mark_node)
3161 value = 1;
3163 /* Prevent further error messages. */
3164 maxindex = build_int_2 (0, 0);
3168 if (!maxindex)
3170 if (do_default)
3171 maxindex = build_int_2 (0, 0);
3172 value = 2;
3175 if (maxindex)
3177 TYPE_DOMAIN (type) = build_index_type (maxindex);
3178 if (!TREE_TYPE (maxindex))
3179 TREE_TYPE (maxindex) = TYPE_DOMAIN (type);
3182 /* Lay out the type now that we can get the real answer. */
3184 layout_type (type);
3186 return value;
3189 /* Determine whether TYPE is a structure with a flexible array member,
3190 or a union containing such a structure (possibly recursively). */
3192 static bool
3193 flexible_array_type_p (tree type)
3195 tree x;
3196 switch (TREE_CODE (type))
3198 case RECORD_TYPE:
3199 x = TYPE_FIELDS (type);
3200 if (x == NULL_TREE)
3201 return false;
3202 while (TREE_CHAIN (x) != NULL_TREE)
3203 x = TREE_CHAIN (x);
3204 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3205 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3206 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3207 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3208 return true;
3209 return false;
3210 case UNION_TYPE:
3211 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3213 if (flexible_array_type_p (TREE_TYPE (x)))
3214 return true;
3216 return false;
3217 default:
3218 return false;
3222 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3223 replacing with appropriate values if they are invalid. */
3224 static void
3225 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3227 tree type_mv;
3228 unsigned int max_width;
3229 unsigned HOST_WIDE_INT w;
3230 const char *name = orig_name ? orig_name: _("<anonymous>");
3232 /* Necessary? */
3233 STRIP_NOPS (*width);
3235 /* Detect and ignore out of range field width and process valid
3236 field widths. */
3237 if (TREE_CODE (*width) != INTEGER_CST)
3239 error ("bit-field `%s' width not an integer constant", name);
3240 *width = integer_one_node;
3242 else
3244 constant_expression_warning (*width);
3245 if (tree_int_cst_sgn (*width) < 0)
3247 error ("negative width in bit-field `%s'", name);
3248 *width = integer_one_node;
3250 else if (integer_zerop (*width) && orig_name)
3252 error ("zero width for bit-field `%s'", name);
3253 *width = integer_one_node;
3257 /* Detect invalid bit-field type. */
3258 if (TREE_CODE (*type) != INTEGER_TYPE
3259 && TREE_CODE (*type) != BOOLEAN_TYPE
3260 && TREE_CODE (*type) != ENUMERAL_TYPE)
3262 error ("bit-field `%s' has invalid type", name);
3263 *type = unsigned_type_node;
3266 type_mv = TYPE_MAIN_VARIANT (*type);
3267 if (pedantic
3268 && type_mv != integer_type_node
3269 && type_mv != unsigned_type_node
3270 && type_mv != boolean_type_node)
3271 pedwarn ("type of bit-field `%s' is a GCC extension", name);
3273 if (type_mv == boolean_type_node)
3274 max_width = CHAR_TYPE_SIZE;
3275 else
3276 max_width = TYPE_PRECISION (*type);
3278 if (0 < compare_tree_int (*width, max_width))
3280 error ("width of `%s' exceeds its type", name);
3281 w = max_width;
3282 *width = build_int_2 (w, 0);
3284 else
3285 w = tree_low_cst (*width, 1);
3287 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3289 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3290 if (!lt
3291 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3292 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3293 warning ("`%s' is narrower than values of its type", name);
3297 /* Given declspecs and a declarator,
3298 determine the name and type of the object declared
3299 and construct a ..._DECL node for it.
3300 (In one case we can return a ..._TYPE node instead.
3301 For invalid input we sometimes return 0.)
3303 DECLSPECS is a chain of tree_list nodes whose value fields
3304 are the storage classes and type specifiers.
3306 DECL_CONTEXT says which syntactic context this declaration is in:
3307 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3308 FUNCDEF for a function definition. Like NORMAL but a few different
3309 error messages in each case. Return value may be zero meaning
3310 this definition is too screwy to try to parse.
3311 PARM for a parameter declaration (either within a function prototype
3312 or before a function body). Make a PARM_DECL, or return void_type_node.
3313 TYPENAME if for a typename (in a cast or sizeof).
3314 Don't make a DECL node; just return the ..._TYPE node.
3315 FIELD for a struct or union field; make a FIELD_DECL.
3316 INITIALIZED is 1 if the decl has an initializer.
3317 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3318 representing the width of the bit-field.
3320 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3321 It may also be so in the PARM case, for a prototype where the
3322 argument type is specified but not the name.
3324 This function is where the complicated C meanings of `static'
3325 and `extern' are interpreted. */
3327 static tree
3328 grokdeclarator (tree declarator, tree declspecs,
3329 enum decl_context decl_context, int initialized, tree *width)
3331 int specbits = 0;
3332 tree spec;
3333 tree type = NULL_TREE;
3334 int longlong = 0;
3335 int constp;
3336 int restrictp;
3337 int volatilep;
3338 int type_quals = TYPE_UNQUALIFIED;
3339 int inlinep;
3340 int explicit_int = 0;
3341 int explicit_char = 0;
3342 int defaulted_int = 0;
3343 tree typedef_decl = 0;
3344 const char *name, *orig_name;
3345 tree typedef_type = 0;
3346 int funcdef_flag = 0;
3347 enum tree_code innermost_code = ERROR_MARK;
3348 int size_varies = 0;
3349 tree decl_attr = NULL_TREE;
3350 tree array_ptr_quals = NULL_TREE;
3351 int array_parm_static = 0;
3352 tree returned_attrs = NULL_TREE;
3353 bool bitfield = width != NULL;
3354 tree element_type;
3355 tree arg_info = NULL_TREE;
3357 if (decl_context == FUNCDEF)
3358 funcdef_flag = 1, decl_context = NORMAL;
3360 /* Look inside a declarator for the name being declared
3361 and get it as a string, for an error message. */
3363 tree decl = declarator;
3364 name = 0;
3366 while (decl)
3367 switch (TREE_CODE (decl))
3369 case ARRAY_REF:
3370 case INDIRECT_REF:
3371 case CALL_EXPR:
3372 innermost_code = TREE_CODE (decl);
3373 decl = TREE_OPERAND (decl, 0);
3374 break;
3376 case TREE_LIST:
3377 decl = TREE_VALUE (decl);
3378 break;
3380 case IDENTIFIER_NODE:
3381 name = IDENTIFIER_POINTER (decl);
3382 decl = 0;
3383 break;
3385 default:
3386 abort ();
3388 orig_name = name;
3389 if (name == 0)
3390 name = "type name";
3393 /* A function definition's declarator must have the form of
3394 a function declarator. */
3396 if (funcdef_flag && innermost_code != CALL_EXPR)
3397 return 0;
3399 /* If this looks like a function definition, make it one,
3400 even if it occurs where parms are expected.
3401 Then store_parm_decls will reject it and not use it as a parm. */
3402 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
3403 decl_context = PARM;
3405 /* Look through the decl specs and record which ones appear.
3406 Some typespecs are defined as built-in typenames.
3407 Others, the ones that are modifiers of other types,
3408 are represented by bits in SPECBITS: set the bits for
3409 the modifiers that appear. Storage class keywords are also in SPECBITS.
3411 If there is a typedef name or a type, store the type in TYPE.
3412 This includes builtin typedefs such as `int'.
3414 Set EXPLICIT_INT or EXPLICIT_CHAR if the type is `int' or `char'
3415 and did not come from a user typedef.
3417 Set LONGLONG if `long' is mentioned twice. */
3419 for (spec = declspecs; spec; spec = TREE_CHAIN (spec))
3421 tree id = TREE_VALUE (spec);
3423 /* If the entire declaration is itself tagged as deprecated then
3424 suppress reports of deprecated items. */
3425 if (id && TREE_DEPRECATED (id))
3427 if (deprecated_state != DEPRECATED_SUPPRESS)
3428 warn_deprecated_use (id);
3431 if (id == ridpointers[(int) RID_INT])
3432 explicit_int = 1;
3433 if (id == ridpointers[(int) RID_CHAR])
3434 explicit_char = 1;
3436 if (TREE_CODE (id) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (id))
3438 enum rid i = C_RID_CODE (id);
3439 if ((int) i <= (int) RID_LAST_MODIFIER)
3441 if (i == RID_LONG && (specbits & (1 << (int) RID_LONG)))
3443 if (longlong)
3444 error ("`long long long' is too long for GCC");
3445 else
3447 if (pedantic && !flag_isoc99 && ! in_system_header
3448 && warn_long_long)
3449 pedwarn ("ISO C90 does not support `long long'");
3450 longlong = 1;
3453 else if (specbits & (1 << (int) i))
3455 if (i == RID_CONST || i == RID_VOLATILE || i == RID_RESTRICT)
3457 if (pedantic && !flag_isoc99)
3458 pedwarn ("duplicate `%s'", IDENTIFIER_POINTER (id));
3460 else
3461 error ("duplicate `%s'", IDENTIFIER_POINTER (id));
3464 /* Diagnose "__thread extern". Recall that this list
3465 is in the reverse order seen in the text. */
3466 if (i == RID_THREAD
3467 && (specbits & (1 << (int) RID_EXTERN
3468 | 1 << (int) RID_STATIC)))
3470 if (specbits & 1 << (int) RID_EXTERN)
3471 error ("`__thread' before `extern'");
3472 else
3473 error ("`__thread' before `static'");
3476 specbits |= 1 << (int) i;
3477 goto found;
3480 if (type)
3481 error ("two or more data types in declaration of `%s'", name);
3482 /* Actual typedefs come to us as TYPE_DECL nodes. */
3483 else if (TREE_CODE (id) == TYPE_DECL)
3485 if (TREE_TYPE (id) == error_mark_node)
3486 ; /* Allow the type to default to int to avoid cascading errors. */
3487 else
3489 type = TREE_TYPE (id);
3490 decl_attr = DECL_ATTRIBUTES (id);
3491 typedef_decl = id;
3494 /* Built-in types come as identifiers. */
3495 else if (TREE_CODE (id) == IDENTIFIER_NODE)
3497 tree t = lookup_name (id);
3498 if (!t || TREE_CODE (t) != TYPE_DECL)
3499 error ("`%s' fails to be a typedef or built in type",
3500 IDENTIFIER_POINTER (id));
3501 else if (TREE_TYPE (t) == error_mark_node)
3503 else
3505 type = TREE_TYPE (t);
3506 typedef_decl = t;
3509 else if (TREE_CODE (id) != ERROR_MARK)
3510 type = id;
3512 found:
3516 typedef_type = type;
3517 if (type)
3518 size_varies = C_TYPE_VARIABLE_SIZE (type);
3520 /* No type at all: default to `int', and set DEFAULTED_INT
3521 because it was not a user-defined typedef. */
3523 if (type == 0)
3525 if ((! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
3526 | (1 << (int) RID_SIGNED)
3527 | (1 << (int) RID_UNSIGNED)
3528 | (1 << (int) RID_COMPLEX))))
3529 /* Don't warn about typedef foo = bar. */
3530 && ! (specbits & (1 << (int) RID_TYPEDEF) && initialized)
3531 && ! in_system_header)
3533 /* Issue a warning if this is an ISO C 99 program or if -Wreturn-type
3534 and this is a function, or if -Wimplicit; prefer the former
3535 warning since it is more explicit. */
3536 if ((warn_implicit_int || warn_return_type || flag_isoc99)
3537 && funcdef_flag)
3538 warn_about_return_type = 1;
3539 else if (warn_implicit_int || flag_isoc99)
3540 pedwarn_c99 ("type defaults to `int' in declaration of `%s'",
3541 name);
3544 defaulted_int = 1;
3545 type = integer_type_node;
3548 /* Now process the modifiers that were specified
3549 and check for invalid combinations. */
3551 /* Long double is a special combination. */
3553 if ((specbits & 1 << (int) RID_LONG) && ! longlong
3554 && TYPE_MAIN_VARIANT (type) == double_type_node)
3556 specbits &= ~(1 << (int) RID_LONG);
3557 type = long_double_type_node;
3560 /* Check all other uses of type modifiers. */
3562 if (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
3563 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED)))
3565 int ok = 0;
3567 if ((specbits & 1 << (int) RID_LONG)
3568 && (specbits & 1 << (int) RID_SHORT))
3569 error ("both long and short specified for `%s'", name);
3570 else if (((specbits & 1 << (int) RID_LONG)
3571 || (specbits & 1 << (int) RID_SHORT))
3572 && explicit_char)
3573 error ("long or short specified with char for `%s'", name);
3574 else if (((specbits & 1 << (int) RID_LONG)
3575 || (specbits & 1 << (int) RID_SHORT))
3576 && TREE_CODE (type) == REAL_TYPE)
3578 static int already = 0;
3580 error ("long or short specified with floating type for `%s'", name);
3581 if (! already && ! pedantic)
3583 error ("the only valid combination is `long double'");
3584 already = 1;
3587 else if ((specbits & 1 << (int) RID_SIGNED)
3588 && (specbits & 1 << (int) RID_UNSIGNED))
3589 error ("both signed and unsigned specified for `%s'", name);
3590 else if (TREE_CODE (type) != INTEGER_TYPE)
3591 error ("long, short, signed or unsigned invalid for `%s'", name);
3592 else
3594 ok = 1;
3595 if (!explicit_int && !defaulted_int && !explicit_char)
3597 error ("long, short, signed or unsigned used invalidly for `%s'",
3598 name);
3599 ok = 0;
3603 /* Discard the type modifiers if they are invalid. */
3604 if (! ok)
3606 specbits &= ~((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
3607 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED));
3608 longlong = 0;
3612 if ((specbits & (1 << (int) RID_COMPLEX))
3613 && TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
3615 error ("complex invalid for `%s'", name);
3616 specbits &= ~(1 << (int) RID_COMPLEX);
3619 /* Decide whether an integer type is signed or not.
3620 Optionally treat bit-fields as signed by default. */
3621 if (specbits & 1 << (int) RID_UNSIGNED
3622 || (bitfield && ! flag_signed_bitfields
3623 && (explicit_int || defaulted_int || explicit_char
3624 /* A typedef for plain `int' without `signed'
3625 can be controlled just like plain `int'. */
3626 || ! (typedef_decl != 0
3627 && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
3628 && TREE_CODE (type) != ENUMERAL_TYPE
3629 && !(specbits & 1 << (int) RID_SIGNED)))
3631 if (longlong)
3632 type = long_long_unsigned_type_node;
3633 else if (specbits & 1 << (int) RID_LONG)
3634 type = long_unsigned_type_node;
3635 else if (specbits & 1 << (int) RID_SHORT)
3636 type = short_unsigned_type_node;
3637 else if (type == char_type_node)
3638 type = unsigned_char_type_node;
3639 else if (typedef_decl)
3640 type = c_common_unsigned_type (type);
3641 else
3642 type = unsigned_type_node;
3644 else if ((specbits & 1 << (int) RID_SIGNED)
3645 && type == char_type_node)
3646 type = signed_char_type_node;
3647 else if (longlong)
3648 type = long_long_integer_type_node;
3649 else if (specbits & 1 << (int) RID_LONG)
3650 type = long_integer_type_node;
3651 else if (specbits & 1 << (int) RID_SHORT)
3652 type = short_integer_type_node;
3654 if (specbits & 1 << (int) RID_COMPLEX)
3656 if (pedantic && !flag_isoc99)
3657 pedwarn ("ISO C90 does not support complex types");
3658 /* If we just have "complex", it is equivalent to
3659 "complex double", but if any modifiers at all are specified it is
3660 the complex form of TYPE. E.g, "complex short" is
3661 "complex short int". */
3663 if (defaulted_int && ! longlong
3664 && ! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
3665 | (1 << (int) RID_SIGNED)
3666 | (1 << (int) RID_UNSIGNED))))
3668 if (pedantic)
3669 pedwarn ("ISO C does not support plain `complex' meaning `double complex'");
3670 type = complex_double_type_node;
3672 else if (type == integer_type_node)
3674 if (pedantic)
3675 pedwarn ("ISO C does not support complex integer types");
3676 type = complex_integer_type_node;
3678 else if (type == float_type_node)
3679 type = complex_float_type_node;
3680 else if (type == double_type_node)
3681 type = complex_double_type_node;
3682 else if (type == long_double_type_node)
3683 type = complex_long_double_type_node;
3684 else
3686 if (pedantic)
3687 pedwarn ("ISO C does not support complex integer types");
3688 type = build_complex_type (type);
3692 /* Check the type and width of a bit-field. */
3693 if (bitfield)
3694 check_bitfield_type_and_width (&type, width, orig_name);
3696 /* Figure out the type qualifiers for the declaration. There are
3697 two ways a declaration can become qualified. One is something
3698 like `const int i' where the `const' is explicit. Another is
3699 something like `typedef const int CI; CI i' where the type of the
3700 declaration contains the `const'. A third possibility is that
3701 there is a type qualifier on the element type of a typedefed
3702 array type, in which case we should extract that qualifier so
3703 that c_apply_type_quals_to_decls receives the full list of
3704 qualifiers to work with (C90 is not entirely clear about whether
3705 duplicate qualifiers should be diagnosed in this case, but it
3706 seems most appropriate to do so). */
3707 element_type = strip_array_types (type);
3708 constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (element_type);
3709 restrictp
3710 = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (element_type);
3711 volatilep
3712 = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (element_type);
3713 inlinep = !! (specbits & (1 << (int) RID_INLINE));
3714 if (pedantic && !flag_isoc99)
3716 if (constp > 1)
3717 pedwarn ("duplicate `const'");
3718 if (restrictp > 1)
3719 pedwarn ("duplicate `restrict'");
3720 if (volatilep > 1)
3721 pedwarn ("duplicate `volatile'");
3723 if (! flag_gen_aux_info && (TYPE_QUALS (type)))
3724 type = TYPE_MAIN_VARIANT (type);
3725 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
3726 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
3727 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
3729 /* Warn if two storage classes are given. Default to `auto'. */
3732 int nclasses = 0;
3734 if (specbits & 1 << (int) RID_AUTO) nclasses++;
3735 if (specbits & 1 << (int) RID_STATIC) nclasses++;
3736 if (specbits & 1 << (int) RID_EXTERN) nclasses++;
3737 if (specbits & 1 << (int) RID_REGISTER) nclasses++;
3738 if (specbits & 1 << (int) RID_TYPEDEF) nclasses++;
3740 /* "static __thread" and "extern __thread" are allowed. */
3741 if ((specbits & (1 << (int) RID_THREAD
3742 | 1 << (int) RID_STATIC
3743 | 1 << (int) RID_EXTERN)) == (1 << (int) RID_THREAD))
3744 nclasses++;
3746 /* Warn about storage classes that are invalid for certain
3747 kinds of declarations (parameters, typenames, etc.). */
3749 if (nclasses > 1)
3750 error ("multiple storage classes in declaration of `%s'", name);
3751 else if (funcdef_flag
3752 && (specbits
3753 & ((1 << (int) RID_REGISTER)
3754 | (1 << (int) RID_AUTO)
3755 | (1 << (int) RID_TYPEDEF)
3756 | (1 << (int) RID_THREAD))))
3758 if (specbits & 1 << (int) RID_AUTO
3759 && (pedantic || current_scope == file_scope))
3760 pedwarn ("function definition declared `auto'");
3761 if (specbits & 1 << (int) RID_REGISTER)
3762 error ("function definition declared `register'");
3763 if (specbits & 1 << (int) RID_TYPEDEF)
3764 error ("function definition declared `typedef'");
3765 if (specbits & 1 << (int) RID_THREAD)
3766 error ("function definition declared `__thread'");
3767 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
3768 | (1 << (int) RID_AUTO) | (1 << (int) RID_THREAD));
3770 else if (decl_context != NORMAL && nclasses > 0)
3772 if (decl_context == PARM && specbits & 1 << (int) RID_REGISTER)
3774 else
3776 switch (decl_context)
3778 case FIELD:
3779 error ("storage class specified for structure field `%s'",
3780 name);
3781 break;
3782 case PARM:
3783 error ("storage class specified for parameter `%s'", name);
3784 break;
3785 default:
3786 error ("storage class specified for typename");
3787 break;
3789 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
3790 | (1 << (int) RID_AUTO) | (1 << (int) RID_STATIC)
3791 | (1 << (int) RID_EXTERN) | (1 << (int) RID_THREAD));
3794 else if (specbits & 1 << (int) RID_EXTERN && initialized && ! funcdef_flag)
3796 /* `extern' with initialization is invalid if not at file scope. */
3797 if (current_scope == file_scope)
3798 warning ("`%s' initialized and declared `extern'", name);
3799 else
3800 error ("`%s' has both `extern' and initializer", name);
3802 else if (current_scope == file_scope)
3804 if (specbits & 1 << (int) RID_AUTO)
3805 error ("file-scope declaration of `%s' specifies `auto'", name);
3807 else
3809 if (specbits & 1 << (int) RID_EXTERN && funcdef_flag)
3810 error ("nested function `%s' declared `extern'", name);
3811 else if ((specbits & (1 << (int) RID_THREAD
3812 | 1 << (int) RID_EXTERN
3813 | 1 << (int) RID_STATIC))
3814 == (1 << (int) RID_THREAD))
3816 error ("function-scope `%s' implicitly auto and declared `__thread'",
3817 name);
3818 specbits &= ~(1 << (int) RID_THREAD);
3823 /* Now figure out the structure of the declarator proper.
3824 Descend through it, creating more complex types, until we reach
3825 the declared identifier (or NULL_TREE, in an absolute declarator). */
3827 while (declarator && TREE_CODE (declarator) != IDENTIFIER_NODE)
3829 if (type == error_mark_node)
3831 declarator = TREE_OPERAND (declarator, 0);
3832 continue;
3835 /* Each level of DECLARATOR is either an ARRAY_REF (for ...[..]),
3836 an INDIRECT_REF (for *...),
3837 a CALL_EXPR (for ...(...)),
3838 a TREE_LIST (for nested attributes),
3839 an identifier (for the name being declared)
3840 or a null pointer (for the place in an absolute declarator
3841 where the name was omitted).
3842 For the last two cases, we have just exited the loop.
3844 At this point, TYPE is the type of elements of an array,
3845 or for a function to return, or for a pointer to point to.
3846 After this sequence of ifs, TYPE is the type of the
3847 array or function or pointer, and DECLARATOR has had its
3848 outermost layer removed. */
3850 if (array_ptr_quals != NULL_TREE || array_parm_static)
3852 /* Only the innermost declarator (making a parameter be of
3853 array type which is converted to pointer type)
3854 may have static or type qualifiers. */
3855 error ("static or type qualifiers in non-parameter array declarator");
3856 array_ptr_quals = NULL_TREE;
3857 array_parm_static = 0;
3860 if (TREE_CODE (declarator) == TREE_LIST)
3862 /* We encode a declarator with embedded attributes using
3863 a TREE_LIST. */
3864 tree attrs = TREE_PURPOSE (declarator);
3865 tree inner_decl;
3866 int attr_flags = 0;
3867 declarator = TREE_VALUE (declarator);
3868 inner_decl = declarator;
3869 while (inner_decl != NULL_TREE
3870 && TREE_CODE (inner_decl) == TREE_LIST)
3871 inner_decl = TREE_VALUE (inner_decl);
3872 if (inner_decl == NULL_TREE
3873 || TREE_CODE (inner_decl) == IDENTIFIER_NODE)
3874 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
3875 else if (TREE_CODE (inner_decl) == CALL_EXPR)
3876 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
3877 else if (TREE_CODE (inner_decl) == ARRAY_REF)
3878 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
3879 returned_attrs = decl_attributes (&type,
3880 chainon (returned_attrs, attrs),
3881 attr_flags);
3883 else if (TREE_CODE (declarator) == ARRAY_REF)
3885 tree itype = NULL_TREE;
3886 tree size = TREE_OPERAND (declarator, 1);
3887 /* The index is a signed object `sizetype' bits wide. */
3888 tree index_type = c_common_signed_type (sizetype);
3890 array_ptr_quals = TREE_TYPE (declarator);
3891 array_parm_static = TREE_STATIC (declarator);
3893 declarator = TREE_OPERAND (declarator, 0);
3895 /* Check for some types that there cannot be arrays of. */
3897 if (VOID_TYPE_P (type))
3899 error ("declaration of `%s' as array of voids", name);
3900 type = error_mark_node;
3903 if (TREE_CODE (type) == FUNCTION_TYPE)
3905 error ("declaration of `%s' as array of functions", name);
3906 type = error_mark_node;
3909 if (pedantic && !in_system_header && flexible_array_type_p (type))
3910 pedwarn ("invalid use of structure with flexible array member");
3912 if (size == error_mark_node)
3913 type = error_mark_node;
3915 if (type == error_mark_node)
3916 continue;
3918 /* If size was specified, set ITYPE to a range-type for that size.
3919 Otherwise, ITYPE remains null. finish_decl may figure it out
3920 from an initial value. */
3922 if (size)
3924 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3925 STRIP_TYPE_NOPS (size);
3927 if (! INTEGRAL_TYPE_P (TREE_TYPE (size)))
3929 error ("size of array `%s' has non-integer type", name);
3930 size = integer_one_node;
3933 if (pedantic && integer_zerop (size))
3934 pedwarn ("ISO C forbids zero-size array `%s'", name);
3936 if (TREE_CODE (size) == INTEGER_CST)
3938 constant_expression_warning (size);
3939 if (tree_int_cst_sgn (size) < 0)
3941 error ("size of array `%s' is negative", name);
3942 size = integer_one_node;
3945 else
3947 /* Make sure the array size remains visibly nonconstant
3948 even if it is (eg) a const variable with known value. */
3949 size_varies = 1;
3951 if (!flag_isoc99 && pedantic)
3953 if (TREE_CONSTANT (size))
3954 pedwarn ("ISO C90 forbids array `%s' whose size can't be evaluated",
3955 name);
3956 else
3957 pedwarn ("ISO C90 forbids variable-size array `%s'",
3958 name);
3962 if (integer_zerop (size))
3964 /* A zero-length array cannot be represented with an
3965 unsigned index type, which is what we'll get with
3966 build_index_type. Create an open-ended range instead. */
3967 itype = build_range_type (sizetype, size, NULL_TREE);
3969 else
3971 /* Compute the maximum valid index, that is, size - 1.
3972 Do the calculation in index_type, so that if it is
3973 a variable the computations will be done in the
3974 proper mode. */
3975 itype = fold (build (MINUS_EXPR, index_type,
3976 convert (index_type, size),
3977 convert (index_type, size_one_node)));
3979 /* If that overflowed, the array is too big.
3980 ??? While a size of INT_MAX+1 technically shouldn't
3981 cause an overflow (because we subtract 1), the overflow
3982 is recorded during the conversion to index_type, before
3983 the subtraction. Handling this case seems like an
3984 unnecessary complication. */
3985 if (TREE_OVERFLOW (itype))
3987 error ("size of array `%s' is too large", name);
3988 type = error_mark_node;
3989 continue;
3992 if (size_varies)
3994 /* We must be able to distinguish the
3995 SAVE_EXPR_CONTEXT for the variably-sized type
3996 so that we can set it correctly in
3997 set_save_expr_context. The convention is
3998 that all SAVE_EXPRs that need to be reset
3999 have NULL_TREE for their SAVE_EXPR_CONTEXT. */
4000 tree cfd = current_function_decl;
4001 if (decl_context == PARM)
4002 current_function_decl = NULL_TREE;
4003 itype = variable_size (itype);
4004 if (decl_context == PARM)
4005 current_function_decl = cfd;
4007 itype = build_index_type (itype);
4010 else if (decl_context == FIELD)
4012 if (pedantic && !flag_isoc99 && !in_system_header)
4013 pedwarn ("ISO C90 does not support flexible array members");
4015 /* ISO C99 Flexible array members are effectively identical
4016 to GCC's zero-length array extension. */
4017 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4020 /* If pedantic, complain about arrays of incomplete types. */
4022 if (pedantic && !COMPLETE_TYPE_P (type))
4023 pedwarn ("array type has incomplete element type");
4025 /* Build the array type itself, then merge any constancy or
4026 volatility into the target type. We must do it in this order
4027 to ensure that the TYPE_MAIN_VARIANT field of the array type
4028 is set correctly. */
4030 type = build_array_type (type, itype);
4031 if (type_quals)
4032 type = c_build_qualified_type (type, type_quals);
4034 if (size_varies)
4035 C_TYPE_VARIABLE_SIZE (type) = 1;
4037 /* The GCC extension for zero-length arrays differs from
4038 ISO flexible array members in that sizeof yields zero. */
4039 if (size && integer_zerop (size))
4041 layout_type (type);
4042 TYPE_SIZE (type) = bitsize_zero_node;
4043 TYPE_SIZE_UNIT (type) = size_zero_node;
4045 else if (declarator && TREE_CODE (declarator) == INDIRECT_REF)
4046 /* We can never complete an array type which is the target of a
4047 pointer, so go ahead and lay it out. */
4048 layout_type (type);
4050 if (decl_context != PARM
4051 && (array_ptr_quals != NULL_TREE || array_parm_static))
4053 error ("static or type qualifiers in non-parameter array declarator");
4054 array_ptr_quals = NULL_TREE;
4055 array_parm_static = 0;
4058 else if (TREE_CODE (declarator) == CALL_EXPR)
4060 /* Say it's a definition only for the CALL_EXPR closest to
4061 the identifier. */
4062 bool really_funcdef = (funcdef_flag
4063 && (TREE_CODE (TREE_OPERAND (declarator, 0))
4064 == IDENTIFIER_NODE));
4065 tree arg_types;
4067 /* Declaring a function type.
4068 Make sure we have a valid type for the function to return. */
4069 if (type == error_mark_node)
4070 continue;
4072 size_varies = 0;
4074 /* Warn about some types functions can't return. */
4076 if (TREE_CODE (type) == FUNCTION_TYPE)
4078 error ("`%s' declared as function returning a function", name);
4079 type = integer_type_node;
4081 if (TREE_CODE (type) == ARRAY_TYPE)
4083 error ("`%s' declared as function returning an array", name);
4084 type = integer_type_node;
4087 /* Construct the function type and go to the next
4088 inner layer of declarator. */
4089 arg_info = TREE_OPERAND (declarator, 1);
4090 arg_types = grokparms (arg_info, really_funcdef);
4092 /* Type qualifiers before the return type of the function
4093 qualify the return type, not the function type. */
4094 if (type_quals)
4096 /* Type qualifiers on a function return type are normally
4097 permitted by the standard but have no effect, so give a
4098 warning at -Wextra. Qualifiers on a void return type have
4099 meaning as a GNU extension, and are banned on function
4100 definitions in ISO C. FIXME: strictly we shouldn't
4101 pedwarn for qualified void return types except on function
4102 definitions, but not doing so could lead to the undesirable
4103 state of a "volatile void" function return type not being
4104 warned about, and a use of the function being compiled
4105 with GNU semantics, with no diagnostics under -pedantic. */
4106 if (VOID_TYPE_P (type) && pedantic && !in_system_header)
4107 pedwarn ("ISO C forbids qualified void function return type");
4108 else if (extra_warnings
4109 && !(VOID_TYPE_P (type)
4110 && type_quals == TYPE_QUAL_VOLATILE))
4111 warning ("type qualifiers ignored on function return type");
4113 type = c_build_qualified_type (type, type_quals);
4115 type_quals = TYPE_UNQUALIFIED;
4117 type = build_function_type (type, arg_types);
4118 declarator = TREE_OPERAND (declarator, 0);
4120 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4121 the formal parameter list of this FUNCTION_TYPE to point to
4122 the FUNCTION_TYPE node itself. */
4125 tree link;
4127 for (link = ARG_INFO_TAGS (arg_info);
4128 link;
4129 link = TREE_CHAIN (link))
4130 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4133 else if (TREE_CODE (declarator) == INDIRECT_REF)
4135 /* Merge any constancy or volatility into the target type
4136 for the pointer. */
4138 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4139 && type_quals)
4140 pedwarn ("ISO C forbids qualified function types");
4141 if (type_quals)
4142 type = c_build_qualified_type (type, type_quals);
4143 type_quals = TYPE_UNQUALIFIED;
4144 size_varies = 0;
4146 type = build_pointer_type (type);
4148 /* Process a list of type modifier keywords
4149 (such as const or volatile) that were given inside the `*'. */
4151 if (TREE_TYPE (declarator))
4153 tree typemodlist;
4154 int erred = 0;
4156 constp = 0;
4157 volatilep = 0;
4158 restrictp = 0;
4159 for (typemodlist = TREE_TYPE (declarator); typemodlist;
4160 typemodlist = TREE_CHAIN (typemodlist))
4162 tree qualifier = TREE_VALUE (typemodlist);
4164 if (C_IS_RESERVED_WORD (qualifier))
4166 if (C_RID_CODE (qualifier) == RID_CONST)
4167 constp++;
4168 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4169 volatilep++;
4170 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4171 restrictp++;
4172 else
4173 erred++;
4175 else
4176 erred++;
4179 if (erred)
4180 error ("invalid type modifier within pointer declarator");
4181 if (pedantic && !flag_isoc99)
4183 if (constp > 1)
4184 pedwarn ("duplicate `const'");
4185 if (volatilep > 1)
4186 pedwarn ("duplicate `volatile'");
4187 if (restrictp > 1)
4188 pedwarn ("duplicate `restrict'");
4191 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4192 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4193 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4196 declarator = TREE_OPERAND (declarator, 0);
4198 else
4199 abort ();
4203 /* Now TYPE has the actual type. */
4205 /* Did array size calculations overflow? */
4207 if (TREE_CODE (type) == ARRAY_TYPE
4208 && COMPLETE_TYPE_P (type)
4209 && TREE_OVERFLOW (TYPE_SIZE (type)))
4211 error ("size of array `%s' is too large", name);
4212 /* If we proceed with the array type as it is, we'll eventually
4213 crash in tree_low_cst(). */
4214 type = error_mark_node;
4217 /* If this is declaring a typedef name, return a TYPE_DECL. */
4219 if (specbits & (1 << (int) RID_TYPEDEF))
4221 tree decl;
4222 /* Note that the grammar rejects storage classes
4223 in typenames, fields or parameters */
4224 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4225 && type_quals)
4226 pedwarn ("ISO C forbids qualified function types");
4227 if (type_quals)
4228 type = c_build_qualified_type (type, type_quals);
4229 decl = build_decl (TYPE_DECL, declarator, type);
4230 if ((specbits & (1 << (int) RID_SIGNED))
4231 || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4232 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4233 decl_attributes (&decl, returned_attrs, 0);
4234 return decl;
4237 /* Detect the case of an array type of unspecified size
4238 which came, as such, direct from a typedef name.
4239 We must copy the type, so that each identifier gets
4240 a distinct type, so that each identifier's size can be
4241 controlled separately by its own initializer. */
4243 if (type != 0 && typedef_type != 0
4244 && TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0
4245 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
4247 type = build_array_type (TREE_TYPE (type), 0);
4248 if (size_varies)
4249 C_TYPE_VARIABLE_SIZE (type) = 1;
4252 /* If this is a type name (such as, in a cast or sizeof),
4253 compute the type and return it now. */
4255 if (decl_context == TYPENAME)
4257 /* Note that the grammar rejects storage classes
4258 in typenames, fields or parameters */
4259 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4260 && type_quals)
4261 pedwarn ("ISO C forbids const or volatile function types");
4262 if (type_quals)
4263 type = c_build_qualified_type (type, type_quals);
4264 decl_attributes (&type, returned_attrs, 0);
4265 return type;
4268 /* Aside from typedefs and type names (handle above),
4269 `void' at top level (not within pointer)
4270 is allowed only in public variables.
4271 We don't complain about parms either, but that is because
4272 a better error message can be made later. */
4274 if (VOID_TYPE_P (type) && decl_context != PARM
4275 && ! ((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4276 && ((specbits & (1 << (int) RID_EXTERN))
4277 || (current_scope == file_scope
4278 && !(specbits
4279 & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)))))))
4281 error ("variable or field `%s' declared void", name);
4282 type = integer_type_node;
4285 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4286 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4289 tree decl;
4291 if (decl_context == PARM)
4293 tree type_as_written;
4294 tree promoted_type;
4296 /* A parameter declared as an array of T is really a pointer to T.
4297 One declared as a function is really a pointer to a function. */
4299 if (TREE_CODE (type) == ARRAY_TYPE)
4301 /* Transfer const-ness of array into that of type pointed to. */
4302 type = TREE_TYPE (type);
4303 if (type_quals)
4304 type = c_build_qualified_type (type, type_quals);
4305 type = build_pointer_type (type);
4306 type_quals = TYPE_UNQUALIFIED;
4307 if (array_ptr_quals)
4309 tree new_ptr_quals, new_ptr_attrs;
4310 int erred = 0;
4311 split_specs_attrs (array_ptr_quals, &new_ptr_quals, &new_ptr_attrs);
4312 /* We don't yet implement attributes in this context. */
4313 if (new_ptr_attrs != NULL_TREE)
4314 warning ("attributes in parameter array declarator ignored");
4316 constp = 0;
4317 volatilep = 0;
4318 restrictp = 0;
4319 for (; new_ptr_quals; new_ptr_quals = TREE_CHAIN (new_ptr_quals))
4321 tree qualifier = TREE_VALUE (new_ptr_quals);
4323 if (C_IS_RESERVED_WORD (qualifier))
4325 if (C_RID_CODE (qualifier) == RID_CONST)
4326 constp++;
4327 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4328 volatilep++;
4329 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4330 restrictp++;
4331 else
4332 erred++;
4334 else
4335 erred++;
4338 if (erred)
4339 error ("invalid type modifier within array declarator");
4341 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4342 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4343 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4345 size_varies = 0;
4347 else if (TREE_CODE (type) == FUNCTION_TYPE)
4349 if (pedantic && type_quals)
4350 pedwarn ("ISO C forbids qualified function types");
4351 if (type_quals)
4352 type = c_build_qualified_type (type, type_quals);
4353 type = build_pointer_type (type);
4354 type_quals = TYPE_UNQUALIFIED;
4356 else if (type_quals)
4357 type = c_build_qualified_type (type, type_quals);
4359 type_as_written = type;
4361 decl = build_decl (PARM_DECL, declarator, type);
4362 if (size_varies)
4363 C_DECL_VARIABLE_SIZE (decl) = 1;
4365 /* Compute the type actually passed in the parmlist,
4366 for the case where there is no prototype.
4367 (For example, shorts and chars are passed as ints.)
4368 When there is a prototype, this is overridden later. */
4370 if (type == error_mark_node)
4371 promoted_type = type;
4372 else
4373 promoted_type = c_type_promotes_to (type);
4375 DECL_ARG_TYPE (decl) = promoted_type;
4376 DECL_ARG_TYPE_AS_WRITTEN (decl) = type_as_written;
4378 else if (decl_context == FIELD)
4380 /* Structure field. It may not be a function. */
4382 if (TREE_CODE (type) == FUNCTION_TYPE)
4384 error ("field `%s' declared as a function", name);
4385 type = build_pointer_type (type);
4387 else if (TREE_CODE (type) != ERROR_MARK
4388 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4390 error ("field `%s' has incomplete type", name);
4391 type = error_mark_node;
4393 /* Move type qualifiers down to element of an array. */
4394 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4395 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4396 type_quals),
4397 TYPE_DOMAIN (type));
4398 decl = build_decl (FIELD_DECL, declarator, type);
4399 DECL_NONADDRESSABLE_P (decl) = bitfield;
4401 if (size_varies)
4402 C_DECL_VARIABLE_SIZE (decl) = 1;
4404 else if (TREE_CODE (type) == FUNCTION_TYPE)
4406 /* Every function declaration is "external"
4407 except for those which are inside a function body
4408 in which `auto' is used.
4409 That is a case not specified by ANSI C,
4410 and we use it for forward declarations for nested functions. */
4411 int extern_ref = (!(specbits & (1 << (int) RID_AUTO))
4412 || current_scope == file_scope);
4414 if (specbits & (1 << (int) RID_AUTO)
4415 && (pedantic || current_scope == file_scope))
4416 pedwarn ("invalid storage class for function `%s'", name);
4417 if (specbits & (1 << (int) RID_REGISTER))
4418 error ("invalid storage class for function `%s'", name);
4419 if (specbits & (1 << (int) RID_THREAD))
4420 error ("invalid storage class for function `%s'", name);
4421 /* Function declaration not at file scope.
4422 Storage classes other than `extern' are not allowed
4423 and `extern' makes no difference. */
4424 if (current_scope != file_scope
4425 && (specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_INLINE)))
4426 && pedantic)
4427 pedwarn ("invalid storage class for function `%s'", name);
4429 decl = build_decl (FUNCTION_DECL, declarator, type);
4430 decl = build_decl_attribute_variant (decl, decl_attr);
4432 DECL_LANG_SPECIFIC (decl)
4433 = ggc_alloc_cleared (sizeof (struct lang_decl));
4435 if (pedantic && type_quals && ! DECL_IN_SYSTEM_HEADER (decl))
4436 pedwarn ("ISO C forbids qualified function types");
4438 /* GNU C interprets a `volatile void' return type to indicate
4439 that the function does not return. */
4440 if ((type_quals & TYPE_QUAL_VOLATILE)
4441 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4442 warning ("`noreturn' function returns non-void value");
4444 if (extern_ref)
4445 DECL_EXTERNAL (decl) = 1;
4446 /* Record absence of global scope for `static' or `auto'. */
4447 TREE_PUBLIC (decl)
4448 = !(specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_AUTO)));
4450 /* For a function definition, record the argument information
4451 block in DECL_ARGUMENTS where store_parm_decls will look
4452 for it. */
4453 if (funcdef_flag)
4454 DECL_ARGUMENTS (decl) = arg_info;
4456 if (defaulted_int)
4457 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4459 /* Record presence of `inline', if it is reasonable. */
4460 if (MAIN_NAME_P (declarator))
4462 if (inlinep)
4463 warning ("cannot inline function `main'");
4465 else if (inlinep)
4467 /* Record that the function is declared `inline'. */
4468 DECL_DECLARED_INLINE_P (decl) = 1;
4470 /* Do not mark bare declarations as DECL_INLINE. Doing so
4471 in the presence of multiple declarations can result in
4472 the abstract origin pointing between the declarations,
4473 which will confuse dwarf2out. */
4474 if (initialized)
4476 DECL_INLINE (decl) = 1;
4477 if (specbits & (1 << (int) RID_EXTERN))
4478 current_extern_inline = 1;
4481 /* If -finline-functions, assume it can be inlined. This does
4482 two things: let the function be deferred until it is actually
4483 needed, and let dwarf2 know that the function is inlinable. */
4484 else if (flag_inline_trees == 2 && initialized)
4485 DECL_INLINE (decl) = 1;
4487 else
4489 /* It's a variable. */
4490 /* An uninitialized decl with `extern' is a reference. */
4491 int extern_ref = !initialized && (specbits & (1 << (int) RID_EXTERN));
4493 /* Move type qualifiers down to element of an array. */
4494 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4496 int saved_align = TYPE_ALIGN(type);
4497 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4498 type_quals),
4499 TYPE_DOMAIN (type));
4500 TYPE_ALIGN (type) = saved_align;
4502 else if (type_quals)
4503 type = c_build_qualified_type (type, type_quals);
4505 /* C99 6.2.2p7: It is invalid (compile-time undefined
4506 behavior) to create an 'extern' declaration for a
4507 variable if there is a global declaration that is
4508 'static' and the global declaration is not visible.
4509 (If the static declaration _is_ currently visible,
4510 the 'extern' declaration is taken to refer to that decl.) */
4511 if (extern_ref && current_scope != file_scope)
4513 tree global_decl = identifier_global_value (declarator);
4514 tree visible_decl = lookup_name (declarator);
4516 if (global_decl
4517 && global_decl != visible_decl
4518 && TREE_CODE (global_decl) == VAR_DECL
4519 && !TREE_PUBLIC (global_decl))
4520 error ("variable previously declared 'static' redeclared "
4521 "'extern'");
4524 decl = build_decl (VAR_DECL, declarator, type);
4525 if (size_varies)
4526 C_DECL_VARIABLE_SIZE (decl) = 1;
4528 if (inlinep)
4529 pedwarn ("%Jvariable '%D' declared `inline'", decl, decl);
4531 DECL_EXTERNAL (decl) = extern_ref;
4533 /* At file scope, the presence of a `static' or `register' storage
4534 class specifier, or the absence of all storage class specifiers
4535 makes this declaration a definition (perhaps tentative). Also,
4536 the absence of both `static' and `register' makes it public. */
4537 if (current_scope == file_scope)
4539 TREE_PUBLIC (decl) = !(specbits & ((1 << (int) RID_STATIC)
4540 | (1 << (int) RID_REGISTER)));
4541 TREE_STATIC (decl) = !extern_ref;
4543 /* Not at file scope, only `static' makes a static definition. */
4544 else
4546 TREE_STATIC (decl) = (specbits & (1 << (int) RID_STATIC)) != 0;
4547 TREE_PUBLIC (decl) = extern_ref;
4550 if (specbits & 1 << (int) RID_THREAD)
4552 if (targetm.have_tls)
4553 DECL_THREAD_LOCAL (decl) = 1;
4554 else
4555 /* A mere warning is sure to result in improper semantics
4556 at runtime. Don't bother to allow this to compile. */
4557 error ("thread-local storage not supported for this target");
4561 /* Record `register' declaration for warnings on &
4562 and in case doing stupid register allocation. */
4564 if (specbits & (1 << (int) RID_REGISTER))
4566 C_DECL_REGISTER (decl) = 1;
4567 DECL_REGISTER (decl) = 1;
4570 /* Record constancy and volatility. */
4571 c_apply_type_quals_to_decl (type_quals, decl);
4573 /* If a type has volatile components, it should be stored in memory.
4574 Otherwise, the fact that those components are volatile
4575 will be ignored, and would even crash the compiler. */
4576 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl)))
4578 /* It is not an error for a structure with volatile fields to
4579 be declared register, but reset DECL_REGISTER since it
4580 cannot actually go in a register. */
4581 int was_reg = C_DECL_REGISTER (decl);
4582 C_DECL_REGISTER (decl) = 0;
4583 DECL_REGISTER (decl) = 0;
4584 c_mark_addressable (decl);
4585 C_DECL_REGISTER (decl) = was_reg;
4588 #ifdef ENABLE_CHECKING
4589 /* This is the earliest point at which we might know the assembler
4590 name of a variable. Thus, if it's known before this, die horribly. */
4591 if (DECL_ASSEMBLER_NAME_SET_P (decl))
4592 abort ();
4593 #endif
4595 decl_attributes (&decl, returned_attrs, 0);
4597 return decl;
4601 /* Decode the parameter-list info for a function type or function definition.
4602 The argument is the value returned by `get_parm_info' (or made in parse.y
4603 if there is an identifier list instead of a parameter decl list).
4604 These two functions are separate because when a function returns
4605 or receives functions then each is called multiple times but the order
4606 of calls is different. The last call to `grokparms' is always the one
4607 that contains the formal parameter names of a function definition.
4609 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4611 FUNCDEF_FLAG is nonzero for a function definition, 0 for
4612 a mere declaration. A nonempty identifier-list gets an error message
4613 when FUNCDEF_FLAG is zero. */
4615 static tree
4616 grokparms (tree arg_info, int funcdef_flag)
4618 tree arg_types = ARG_INFO_TYPES (arg_info);
4620 if (warn_strict_prototypes && arg_types == 0 && !funcdef_flag
4621 && !in_system_header)
4622 warning ("function declaration isn't a prototype");
4624 if (arg_types == error_mark_node)
4625 return 0; /* don't set TYPE_ARG_TYPES in this case */
4627 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
4629 if (! funcdef_flag)
4630 pedwarn ("parameter names (without types) in function declaration");
4632 ARG_INFO_PARMS (arg_info) = ARG_INFO_TYPES (arg_info);
4633 ARG_INFO_TYPES (arg_info) = 0;
4634 return 0;
4636 else
4638 tree parm, type, typelt;
4639 unsigned int parmno;
4641 /* If the arg types are incomplete in a declaration, they must
4642 include undefined tags. These tags can never be defined in
4643 the scope of the declaration, so the types can never be
4644 completed, and no call can be compiled successfully. */
4646 for (parm = ARG_INFO_PARMS (arg_info), typelt = arg_types, parmno = 1;
4647 parm;
4648 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
4650 type = TREE_VALUE (typelt);
4651 if (type == error_mark_node)
4652 continue;
4654 if (!COMPLETE_TYPE_P (type))
4656 if (funcdef_flag)
4658 if (DECL_NAME (parm))
4659 error ("%Jparameter %u ('%D') has incomplete type",
4660 parm, parmno, parm);
4661 else
4662 error ("%Jparameter %u has incomplete type",
4663 parm, parmno);
4665 TREE_VALUE (typelt) = error_mark_node;
4666 TREE_TYPE (parm) = error_mark_node;
4668 else
4670 if (DECL_NAME (parm))
4671 warning ("%Jparameter %u ('%D') has incomplete type",
4672 parm, parmno, parm);
4673 else
4674 warning ("%Jparameter %u has incomplete type",
4675 parm, parmno);
4679 return arg_types;
4683 /* Take apart the current scope and return a tree_list node with info
4684 on a parameter list just parsed. This tree_list node should be
4685 examined using the ARG_INFO_* macros, defined above:
4687 ARG_INFO_PARMS: a list of parameter decls.
4688 ARG_INFO_TAGS: a list of structure, union and enum tags defined.
4689 ARG_INFO_TYPES: a list of argument types to go in the FUNCTION_TYPE.
4690 ARG_INFO_OTHERS: a list of non-parameter decls (notably enumeration
4691 constants) defined with the parameters.
4693 This tree_list node is later fed to 'grokparms' and 'store_parm_decls'.
4695 ELLIPSIS being true means the argument list ended in '...' so don't
4696 append a sentinel (void_list_node) to the end of the type-list. */
4698 tree
4699 get_parm_info (bool ellipsis)
4701 struct c_binding *b = current_scope->bindings;
4702 tree arg_info = make_node (TREE_LIST);
4703 tree parms = 0;
4704 tree tags = 0;
4705 tree types = 0;
4706 tree others = 0;
4708 static bool explained_incomplete_types = false;
4709 bool gave_void_only_once_err = false;
4711 /* The bindings in this scope must not get put into a block.
4712 We will take care of deleting the binding nodes. */
4713 current_scope->bindings = 0;
4715 /* This function is only called if there was *something* on the
4716 parameter list. */
4717 #ifdef ENABLE_CHECKING
4718 if (b == 0)
4719 abort ();
4720 #endif
4722 /* A parameter list consisting solely of 'void' indicates that the
4723 function takes no arguments. But if the 'void' is qualified
4724 (by 'const' or 'volatile'), or has a storage class specifier
4725 ('register'), then the behavior is undefined; issue an error.
4726 Typedefs for 'void' are OK (see DR#157). */
4727 if (b->prev == 0 /* one binding */
4728 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
4729 && !DECL_NAME (b->decl) /* anonymous */
4730 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
4732 if (TREE_THIS_VOLATILE (b->decl)
4733 || TREE_READONLY (b->decl)
4734 || C_DECL_REGISTER (b->decl))
4735 error ("'void' as only parameter may not be qualified");
4737 /* There cannot be an ellipsis. */
4738 if (ellipsis)
4739 error ("'void' must be the only parameter");
4741 ARG_INFO_TYPES (arg_info) = void_list_node;
4742 return arg_info;
4745 if (!ellipsis)
4746 types = void_list_node;
4748 /* Break up the bindings list into parms, tags, types, and others;
4749 apply sanity checks; purge the name-to-decl bindings. */
4750 while (b)
4752 tree decl = b->decl;
4753 tree type = TREE_TYPE (decl);
4754 const char *keyword;
4756 switch (TREE_CODE (decl))
4758 case PARM_DECL:
4759 if (b->id)
4761 #ifdef ENABLE_CHECKING
4762 if (I_SYMBOL_BINDING (b->id) != b) abort ();
4763 #endif
4764 I_SYMBOL_BINDING (b->id) = b->shadowed;
4767 /* Check for forward decls that never got their actual decl. */
4768 if (TREE_ASM_WRITTEN (decl))
4769 error ("%Jparameter '%D' has just a forward declaration",
4770 decl, decl);
4771 /* Check for (..., void, ...) and issue an error. */
4772 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
4774 if (!gave_void_only_once_err)
4776 error ("'void' must be the only parameter");
4777 gave_void_only_once_err = true;
4780 else
4782 /* Valid parameter, add it to the list. */
4783 TREE_CHAIN (decl) = parms;
4784 parms = decl;
4786 /* Since there is a prototype, args are passed in their
4787 declared types. The back end may override this later. */
4788 DECL_ARG_TYPE (decl) = type;
4789 types = tree_cons (0, type, types);
4791 break;
4793 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
4794 case UNION_TYPE: keyword = "union"; goto tag;
4795 case RECORD_TYPE: keyword = "struct"; goto tag;
4796 tag:
4797 /* Types may not have tag-names, in which case the type
4798 appears in the bindings list with b->id NULL. */
4799 if (b->id)
4801 #ifdef ENABLE_CHECKING
4802 if (I_TAG_BINDING (b->id) != b) abort ();
4803 #endif
4804 I_TAG_BINDING (b->id) = b->shadowed;
4807 /* Warn about any struct, union or enum tags defined in a
4808 parameter list. The scope of such types is limited to
4809 the parameter list, which is rarely if ever desirable
4810 (it's impossible to call such a function with type-
4811 correct arguments). An anonymous union parm type is
4812 meaningful as a GNU extension, so don't warn for that. */
4813 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
4815 if (b->id)
4816 /* The %s will be one of 'struct', 'union', or 'enum'. */
4817 warning ("'%s %E' declared inside parameter list",
4818 keyword, b->id);
4819 else
4820 /* The %s will be one of 'struct', 'union', or 'enum'. */
4821 warning ("anonymous %s declared inside parameter list",
4822 keyword);
4824 if (! explained_incomplete_types)
4826 warning ("its scope is only this definition or declaration,"
4827 " which is probably not what you want");
4828 explained_incomplete_types = true;
4832 tags = tree_cons (b->id, decl, tags);
4833 break;
4835 case CONST_DECL:
4836 case TYPE_DECL:
4837 /* CONST_DECLs appear here when we have an embedded enum,
4838 and TYPE_DECLs appear here when we have an embedded struct
4839 or union. No warnings for this - we already warned about the
4840 type itself. */
4841 TREE_CHAIN (decl) = others;
4842 others = decl;
4843 /* fall through */
4845 case ERROR_MARK:
4846 /* error_mark_node appears here when we have an undeclared
4847 variable. Just throw it away. */
4848 if (b->id)
4850 #ifdef ENABLE_CHECKING
4851 if (I_SYMBOL_BINDING (b->id) != b) abort ();
4852 #endif
4853 I_SYMBOL_BINDING (b->id) = b->shadowed;
4855 break;
4857 /* Other things that might be encountered. */
4858 case LABEL_DECL:
4859 case FUNCTION_DECL:
4860 case VAR_DECL:
4861 default:
4862 abort ();
4865 b = free_binding_and_advance (b);
4868 ARG_INFO_PARMS (arg_info) = parms;
4869 ARG_INFO_TAGS (arg_info) = tags;
4870 ARG_INFO_TYPES (arg_info) = types;
4871 ARG_INFO_OTHERS (arg_info) = others;
4872 return arg_info;
4875 /* Get the struct, enum or union (CODE says which) with tag NAME.
4876 Define the tag as a forward-reference if it is not defined. */
4878 tree
4879 xref_tag (enum tree_code code, tree name)
4881 /* If a cross reference is requested, look up the type
4882 already defined for this tag and return it. */
4884 tree ref = lookup_tag (code, name, 0);
4885 /* If this is the right type of tag, return what we found.
4886 (This reference will be shadowed by shadow_tag later if appropriate.)
4887 If this is the wrong type of tag, do not return it. If it was the
4888 wrong type in the same scope, we will have had an error
4889 message already; if in a different scope and declaring
4890 a name, pending_xref_error will give an error message; but if in a
4891 different scope and not declaring a name, this tag should
4892 shadow the previous declaration of a different type of tag, and
4893 this would not work properly if we return the reference found.
4894 (For example, with "struct foo" in an outer scope, "union foo;"
4895 must shadow that tag with a new one of union type.) */
4896 if (ref && TREE_CODE (ref) == code)
4897 return ref;
4899 /* If no such tag is yet defined, create a forward-reference node
4900 and record it as the "definition".
4901 When a real declaration of this type is found,
4902 the forward-reference will be altered into a real type. */
4904 ref = make_node (code);
4905 if (code == ENUMERAL_TYPE)
4907 /* Give the type a default layout like unsigned int
4908 to avoid crashing if it does not get defined. */
4909 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
4910 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
4911 TYPE_USER_ALIGN (ref) = 0;
4912 TYPE_UNSIGNED (ref) = 1;
4913 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
4914 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
4915 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
4918 pushtag (name, ref);
4920 return ref;
4923 /* Make sure that the tag NAME is defined *in the current scope*
4924 at least as a forward reference.
4925 CODE says which kind of tag NAME ought to be. */
4927 tree
4928 start_struct (enum tree_code code, tree name)
4930 /* If there is already a tag defined at this scope
4931 (as a forward reference), just return it. */
4933 tree ref = 0;
4935 if (name != 0)
4936 ref = lookup_tag (code, name, 1);
4937 if (ref && TREE_CODE (ref) == code)
4939 if (TYPE_FIELDS (ref))
4941 if (code == UNION_TYPE)
4942 error ("redefinition of `union %s'", IDENTIFIER_POINTER (name));
4943 else
4944 error ("redefinition of `struct %s'", IDENTIFIER_POINTER (name));
4947 else
4949 /* Otherwise create a forward-reference just so the tag is in scope. */
4951 ref = make_node (code);
4952 pushtag (name, ref);
4955 C_TYPE_BEING_DEFINED (ref) = 1;
4956 TYPE_PACKED (ref) = flag_pack_struct;
4957 return ref;
4960 /* Process the specs, declarator (NULL if omitted) and width (NULL if omitted)
4961 of a structure component, returning a FIELD_DECL node.
4962 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
4964 This is done during the parsing of the struct declaration.
4965 The FIELD_DECL nodes are chained together and the lot of them
4966 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
4968 tree
4969 grokfield (tree declarator, tree declspecs, tree width)
4971 tree value;
4973 if (declarator == NULL_TREE && width == NULL_TREE)
4975 /* This is an unnamed decl.
4977 If we have something of the form "union { list } ;" then this
4978 is the anonymous union extension. Similarly for struct.
4980 If this is something of the form "struct foo;", then
4981 If MS extensions are enabled, this is handled as an
4982 anonymous struct.
4983 Otherwise this is a forward declaration of a structure tag.
4985 If this is something of the form "foo;" and foo is a TYPE_DECL, then
4986 If MS extensions are enabled and foo names a structure, then
4987 again this is an anonymous struct.
4988 Otherwise this is an error.
4990 Oh what a horrid tangled web we weave. I wonder if MS consciously
4991 took this from Plan 9 or if it was an accident of implementation
4992 that took root before someone noticed the bug... */
4994 tree type = TREE_VALUE (declspecs);
4996 if (flag_ms_extensions && TREE_CODE (type) == TYPE_DECL)
4997 type = TREE_TYPE (type);
4998 if (TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE)
5000 if (flag_ms_extensions)
5001 ; /* ok */
5002 else if (flag_iso)
5003 goto warn_unnamed_field;
5004 else if (TYPE_NAME (type) == NULL)
5005 ; /* ok */
5006 else
5007 goto warn_unnamed_field;
5009 else
5011 warn_unnamed_field:
5012 warning ("declaration does not declare anything");
5013 return NULL_TREE;
5017 value = grokdeclarator (declarator, declspecs, FIELD, 0,
5018 width ? &width : NULL);
5020 finish_decl (value, NULL_TREE, NULL_TREE);
5021 DECL_INITIAL (value) = width;
5023 return value;
5026 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5027 the list such that this does not present a problem later. */
5029 static void
5030 detect_field_duplicates (tree fieldlist)
5032 tree x, y;
5033 int timeout = 10;
5035 /* First, see if there are more than "a few" fields.
5036 This is trivially true if there are zero or one fields. */
5037 if (!fieldlist)
5038 return;
5039 x = TREE_CHAIN (fieldlist);
5040 if (!x)
5041 return;
5042 do {
5043 timeout--;
5044 x = TREE_CHAIN (x);
5045 } while (timeout > 0 && x);
5047 /* If there were "few" fields, avoid the overhead of allocating
5048 a hash table. Instead just do the nested traversal thing. */
5049 if (timeout > 0)
5051 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5052 if (DECL_NAME (x))
5054 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5055 if (DECL_NAME (y) == DECL_NAME (x))
5057 error ("%Jduplicate member '%D'", x, x);
5058 DECL_NAME (x) = NULL_TREE;
5062 else
5064 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5065 void **slot;
5067 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5068 if ((y = DECL_NAME (x)) != 0)
5070 slot = htab_find_slot (htab, y, INSERT);
5071 if (*slot)
5073 error ("%Jduplicate member '%D'", x, x);
5074 DECL_NAME (x) = NULL_TREE;
5076 *slot = y;
5079 htab_delete (htab);
5083 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5084 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5085 ATTRIBUTES are attributes to be applied to the structure. */
5087 tree
5088 finish_struct (tree t, tree fieldlist, tree attributes)
5090 tree x;
5091 bool toplevel = file_scope == current_scope;
5092 int saw_named_field;
5094 /* If this type was previously laid out as a forward reference,
5095 make sure we lay it out again. */
5097 TYPE_SIZE (t) = 0;
5099 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5101 if (pedantic)
5103 for (x = fieldlist; x; x = TREE_CHAIN (x))
5104 if (DECL_NAME (x) != 0)
5105 break;
5107 if (x == 0)
5108 pedwarn ("%s has no %s",
5109 TREE_CODE (t) == UNION_TYPE ? _("union") : _("struct"),
5110 fieldlist ? _("named members") : _("members"));
5113 /* Install struct as DECL_CONTEXT of each field decl.
5114 Also process specified field sizes,m which is found in the DECL_INITIAL.
5115 Store 0 there, except for ": 0" fields (so we can find them
5116 and delete them, below). */
5118 saw_named_field = 0;
5119 for (x = fieldlist; x; x = TREE_CHAIN (x))
5121 DECL_CONTEXT (x) = t;
5122 DECL_PACKED (x) |= TYPE_PACKED (t);
5124 /* If any field is const, the structure type is pseudo-const. */
5125 if (TREE_READONLY (x))
5126 C_TYPE_FIELDS_READONLY (t) = 1;
5127 else
5129 /* A field that is pseudo-const makes the structure likewise. */
5130 tree t1 = TREE_TYPE (x);
5131 while (TREE_CODE (t1) == ARRAY_TYPE)
5132 t1 = TREE_TYPE (t1);
5133 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5134 && C_TYPE_FIELDS_READONLY (t1))
5135 C_TYPE_FIELDS_READONLY (t) = 1;
5138 /* Any field that is volatile means variables of this type must be
5139 treated in some ways as volatile. */
5140 if (TREE_THIS_VOLATILE (x))
5141 C_TYPE_FIELDS_VOLATILE (t) = 1;
5143 /* Any field of nominal variable size implies structure is too. */
5144 if (C_DECL_VARIABLE_SIZE (x))
5145 C_TYPE_VARIABLE_SIZE (t) = 1;
5147 /* Detect invalid nested redefinition. */
5148 if (TREE_TYPE (x) == t)
5149 error ("nested redefinition of `%s'",
5150 IDENTIFIER_POINTER (TYPE_NAME (t)));
5152 if (DECL_INITIAL (x))
5154 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5155 DECL_SIZE (x) = bitsize_int (width);
5156 DECL_BIT_FIELD (x) = 1;
5157 SET_DECL_C_BIT_FIELD (x);
5160 DECL_INITIAL (x) = 0;
5162 /* Detect flexible array member in an invalid context. */
5163 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5164 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5165 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5166 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5168 if (TREE_CODE (t) == UNION_TYPE)
5170 error ("%Jflexible array member in union", x);
5171 TREE_TYPE (x) = error_mark_node;
5173 else if (TREE_CHAIN (x) != NULL_TREE)
5175 error ("%Jflexible array member not at end of struct", x);
5176 TREE_TYPE (x) = error_mark_node;
5178 else if (! saw_named_field)
5180 error ("%Jflexible array member in otherwise empty struct", x);
5181 TREE_TYPE (x) = error_mark_node;
5185 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5186 && flexible_array_type_p (TREE_TYPE (x)))
5187 pedwarn ("%Jinvalid use of structure with flexible array member", x);
5189 if (DECL_NAME (x))
5190 saw_named_field = 1;
5193 detect_field_duplicates (fieldlist);
5195 /* Now we have the nearly final fieldlist. Record it,
5196 then lay out the structure or union (including the fields). */
5198 TYPE_FIELDS (t) = fieldlist;
5200 layout_type (t);
5202 /* Delete all zero-width bit-fields from the fieldlist. */
5204 tree *fieldlistp = &fieldlist;
5205 while (*fieldlistp)
5206 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp))
5207 *fieldlistp = TREE_CHAIN (*fieldlistp);
5208 else
5209 fieldlistp = &TREE_CHAIN (*fieldlistp);
5212 /* Now we have the truly final field list.
5213 Store it in this type and in the variants. */
5215 TYPE_FIELDS (t) = fieldlist;
5217 /* If there are lots of fields, sort so we can look through them fast.
5218 We arbitrarily consider 16 or more elts to be "a lot". */
5221 int len = 0;
5223 for (x = fieldlist; x; x = TREE_CHAIN (x))
5225 if (len > 15 || DECL_NAME (x) == NULL)
5226 break;
5227 len += 1;
5230 if (len > 15)
5232 tree *field_array;
5233 struct lang_type *space;
5234 struct sorted_fields_type *space2;
5236 len += list_length (x);
5238 /* Use the same allocation policy here that make_node uses, to
5239 ensure that this lives as long as the rest of the struct decl.
5240 All decls in an inline function need to be saved. */
5242 space = ggc_alloc_cleared (sizeof (struct lang_type));
5243 space2 = ggc_alloc (sizeof (struct sorted_fields_type) + len * sizeof (tree));
5245 len = 0;
5246 space->s = space2;
5247 field_array = &space2->elts[0];
5248 for (x = fieldlist; x; x = TREE_CHAIN (x))
5250 field_array[len++] = x;
5252 /* If there is anonymous struct or union, break out of the loop. */
5253 if (DECL_NAME (x) == NULL)
5254 break;
5256 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5257 if (x == NULL)
5259 TYPE_LANG_SPECIFIC (t) = space;
5260 TYPE_LANG_SPECIFIC (t)->s->len = len;
5261 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5262 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5267 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5269 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5270 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5271 TYPE_ALIGN (x) = TYPE_ALIGN (t);
5272 TYPE_USER_ALIGN (x) = TYPE_USER_ALIGN (t);
5275 /* If this was supposed to be a transparent union, but we can't
5276 make it one, warn and turn off the flag. */
5277 if (TREE_CODE (t) == UNION_TYPE
5278 && TYPE_TRANSPARENT_UNION (t)
5279 && TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t)))
5281 TYPE_TRANSPARENT_UNION (t) = 0;
5282 warning ("union cannot be made transparent");
5285 /* If this structure or union completes the type of any previous
5286 variable declaration, lay it out and output its rtl. */
5287 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5289 x = TREE_CHAIN (x))
5291 tree decl = TREE_VALUE (x);
5292 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5293 layout_array_type (TREE_TYPE (decl));
5294 if (TREE_CODE (decl) != TYPE_DECL)
5296 layout_decl (decl, 0);
5297 if (c_dialect_objc ())
5298 objc_check_decl (decl);
5299 rest_of_decl_compilation (decl, NULL, toplevel, 0);
5300 if (! toplevel)
5301 expand_decl (decl);
5304 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5306 /* Finish debugging output for this type. */
5307 rest_of_type_compilation (t, toplevel);
5309 return t;
5312 /* Lay out the type T, and its element type, and so on. */
5314 static void
5315 layout_array_type (tree t)
5317 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5318 layout_array_type (TREE_TYPE (t));
5319 layout_type (t);
5322 /* Begin compiling the definition of an enumeration type.
5323 NAME is its name (or null if anonymous).
5324 Returns the type object, as yet incomplete.
5325 Also records info about it so that build_enumerator
5326 may be used to declare the individual values as they are read. */
5328 tree
5329 start_enum (tree name)
5331 tree enumtype = 0;
5333 /* If this is the real definition for a previous forward reference,
5334 fill in the contents in the same object that used to be the
5335 forward reference. */
5337 if (name != 0)
5338 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5340 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5342 enumtype = make_node (ENUMERAL_TYPE);
5343 pushtag (name, enumtype);
5346 C_TYPE_BEING_DEFINED (enumtype) = 1;
5348 if (TYPE_VALUES (enumtype) != 0)
5350 /* This enum is a named one that has been declared already. */
5351 error ("redeclaration of `enum %s'", IDENTIFIER_POINTER (name));
5353 /* Completely replace its old definition.
5354 The old enumerators remain defined, however. */
5355 TYPE_VALUES (enumtype) = 0;
5358 enum_next_value = integer_zero_node;
5359 enum_overflow = 0;
5361 if (flag_short_enums)
5362 TYPE_PACKED (enumtype) = 1;
5364 return enumtype;
5367 /* After processing and defining all the values of an enumeration type,
5368 install their decls in the enumeration type and finish it off.
5369 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5370 and ATTRIBUTES are the specified attributes.
5371 Returns ENUMTYPE. */
5373 tree
5374 finish_enum (tree enumtype, tree values, tree attributes)
5376 tree pair, tem;
5377 tree minnode = 0, maxnode = 0;
5378 int precision, unsign;
5379 bool toplevel = (file_scope == current_scope);
5380 struct lang_type *lt;
5382 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5384 /* Calculate the maximum value of any enumerator in this type. */
5386 if (values == error_mark_node)
5387 minnode = maxnode = integer_zero_node;
5388 else
5390 minnode = maxnode = TREE_VALUE (values);
5391 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5393 tree value = TREE_VALUE (pair);
5394 if (tree_int_cst_lt (maxnode, value))
5395 maxnode = value;
5396 if (tree_int_cst_lt (value, minnode))
5397 minnode = value;
5401 /* Construct the final type of this enumeration. It is the same
5402 as one of the integral types - the narrowest one that fits, except
5403 that normally we only go as narrow as int - and signed iff any of
5404 the values are negative. */
5405 unsign = (tree_int_cst_sgn (minnode) >= 0);
5406 precision = MAX (min_precision (minnode, unsign),
5407 min_precision (maxnode, unsign));
5408 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5410 tem = c_common_type_for_size (precision, unsign);
5411 if (tem == NULL)
5413 warning ("enumeration values exceed range of largest integer");
5414 tem = long_long_integer_type_node;
5417 else
5418 tem = unsign ? unsigned_type_node : integer_type_node;
5420 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5421 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5422 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5423 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5424 TYPE_SIZE (enumtype) = 0;
5425 layout_type (enumtype);
5427 if (values != error_mark_node)
5429 /* Change the type of the enumerators to be the enum type. We
5430 need to do this irrespective of the size of the enum, for
5431 proper type checking. Replace the DECL_INITIALs of the
5432 enumerators, and the value slots of the list, with copies
5433 that have the enum type; they cannot be modified in place
5434 because they may be shared (e.g. integer_zero_node) Finally,
5435 change the purpose slots to point to the names of the decls. */
5436 for (pair = values; pair; pair = TREE_CHAIN (pair))
5438 tree enu = TREE_PURPOSE (pair);
5439 tree ini = DECL_INITIAL (enu);
5441 TREE_TYPE (enu) = enumtype;
5443 /* The ISO C Standard mandates enumerators to have type int,
5444 even though the underlying type of an enum type is
5445 unspecified. Here we convert any enumerators that fit in
5446 an int to type int, to avoid promotions to unsigned types
5447 when comparing integers with enumerators that fit in the
5448 int range. When -pedantic is given, build_enumerator()
5449 would have already taken care of those that don't fit. */
5450 if (int_fits_type_p (ini, integer_type_node))
5451 tem = integer_type_node;
5452 else
5453 tem = enumtype;
5454 ini = convert (tem, ini);
5456 DECL_INITIAL (enu) = ini;
5457 TREE_PURPOSE (pair) = DECL_NAME (enu);
5458 TREE_VALUE (pair) = ini;
5461 TYPE_VALUES (enumtype) = values;
5464 /* Record the min/max values so that we can warn about bit-field
5465 enumerations that are too small for the values. */
5466 lt = ggc_alloc_cleared (sizeof (struct lang_type));
5467 lt->enum_min = minnode;
5468 lt->enum_max = maxnode;
5469 TYPE_LANG_SPECIFIC (enumtype) = lt;
5471 /* Fix up all variant types of this enum type. */
5472 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5474 if (tem == enumtype)
5475 continue;
5476 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5477 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5478 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5479 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5480 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5481 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5482 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5483 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5484 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5485 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5486 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5489 /* Finish debugging output for this type. */
5490 rest_of_type_compilation (enumtype, toplevel);
5492 return enumtype;
5495 /* Build and install a CONST_DECL for one value of the
5496 current enumeration type (one that was begun with start_enum).
5497 Return a tree-list containing the CONST_DECL and its value.
5498 Assignment of sequential values by default is handled here. */
5500 tree
5501 build_enumerator (tree name, tree value)
5503 tree decl, type;
5505 /* Validate and default VALUE. */
5507 /* Remove no-op casts from the value. */
5508 if (value)
5509 STRIP_TYPE_NOPS (value);
5511 if (value != 0)
5513 /* Don't issue more errors for error_mark_node (i.e. an
5514 undeclared identifier) - just ignore the value expression. */
5515 if (value == error_mark_node)
5516 value = 0;
5517 else if (TREE_CODE (value) != INTEGER_CST)
5519 error ("enumerator value for '%E' is not an integer constant", name);
5520 value = 0;
5522 else
5524 value = default_conversion (value);
5525 constant_expression_warning (value);
5529 /* Default based on previous value. */
5530 /* It should no longer be possible to have NON_LVALUE_EXPR
5531 in the default. */
5532 if (value == 0)
5534 value = enum_next_value;
5535 if (enum_overflow)
5536 error ("overflow in enumeration values");
5539 if (pedantic && ! int_fits_type_p (value, integer_type_node))
5541 pedwarn ("ISO C restricts enumerator values to range of `int'");
5542 /* XXX This causes -pedantic to change the meaning of the program.
5543 Remove? -zw 2004-03-15 */
5544 value = convert (integer_type_node, value);
5547 /* Set basis for default for next value. */
5548 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
5549 enum_overflow = tree_int_cst_lt (enum_next_value, value);
5551 /* Now create a declaration for the enum value name. */
5553 type = TREE_TYPE (value);
5554 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
5555 TYPE_PRECISION (integer_type_node)),
5556 (TYPE_PRECISION (type)
5557 >= TYPE_PRECISION (integer_type_node)
5558 && TYPE_UNSIGNED (type)));
5560 decl = build_decl (CONST_DECL, name, type);
5561 DECL_INITIAL (decl) = convert (type, value);
5562 pushdecl (decl);
5564 return tree_cons (decl, value, NULL_TREE);
5568 /* Create the FUNCTION_DECL for a function definition.
5569 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
5570 the declaration; they describe the function's name and the type it returns,
5571 but twisted together in a fashion that parallels the syntax of C.
5573 This function creates a binding context for the function body
5574 as well as setting up the FUNCTION_DECL in current_function_decl.
5576 Returns 1 on success. If the DECLARATOR is not suitable for a function
5577 (it defines a datum instead), we return 0, which tells
5578 yyparse to report a parse error. */
5581 start_function (tree declspecs, tree declarator, tree attributes)
5583 tree decl1, old_decl;
5584 tree restype;
5586 current_function_returns_value = 0; /* Assume, until we see it does. */
5587 current_function_returns_null = 0;
5588 current_function_returns_abnormally = 0;
5589 warn_about_return_type = 0;
5590 current_extern_inline = 0;
5591 c_switch_stack = NULL;
5593 /* Indicate no valid break/continue context by setting these variables
5594 to some non-null, non-label value. We'll notice and emit the proper
5595 error message in c_finish_bc_stmt. */
5596 c_break_label = c_cont_label = size_zero_node;
5598 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1, NULL);
5600 /* If the declarator is not suitable for a function definition,
5601 cause a syntax error. */
5602 if (decl1 == 0)
5603 return 0;
5605 decl_attributes (&decl1, attributes, 0);
5607 if (DECL_DECLARED_INLINE_P (decl1)
5608 && DECL_UNINLINABLE (decl1)
5609 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
5610 warning ("%Jinline function '%D' given attribute noinline", decl1, decl1);
5612 announce_function (decl1);
5614 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
5616 error ("return type is an incomplete type");
5617 /* Make it return void instead. */
5618 TREE_TYPE (decl1)
5619 = build_function_type (void_type_node,
5620 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
5623 if (warn_about_return_type)
5624 pedwarn_c99 ("return type defaults to `int'");
5626 /* Make the init_value nonzero so pushdecl knows this is not tentative.
5627 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
5628 DECL_INITIAL (decl1) = error_mark_node;
5630 /* If this definition isn't a prototype and we had a prototype declaration
5631 before, copy the arg type info from that prototype.
5632 But not if what we had before was a builtin function. */
5633 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
5634 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
5635 && !DECL_BUILT_IN (old_decl)
5636 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
5637 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (old_decl))))
5638 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
5640 TREE_TYPE (decl1) = TREE_TYPE (old_decl);
5641 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
5644 /* Optionally warn of old-fashioned def with no previous prototype. */
5645 if (warn_strict_prototypes
5646 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
5647 && C_DECL_ISNT_PROTOTYPE (old_decl))
5648 warning ("function declaration isn't a prototype");
5649 /* Optionally warn of any global def with no previous prototype. */
5650 else if (warn_missing_prototypes
5651 && TREE_PUBLIC (decl1)
5652 && ! MAIN_NAME_P (DECL_NAME (decl1))
5653 && C_DECL_ISNT_PROTOTYPE (old_decl))
5654 warning ("%Jno previous prototype for '%D'", decl1, decl1);
5655 /* Optionally warn of any def with no previous prototype
5656 if the function has already been used. */
5657 else if (warn_missing_prototypes
5658 && old_decl != 0 && TREE_USED (old_decl)
5659 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
5660 warning ("%J'%D' was used with no prototype before its definition",
5661 decl1, decl1);
5662 /* Optionally warn of any global def with no previous declaration. */
5663 else if (warn_missing_declarations
5664 && TREE_PUBLIC (decl1)
5665 && old_decl == 0
5666 && ! MAIN_NAME_P (DECL_NAME (decl1)))
5667 warning ("%Jno previous declaration for '%D'", decl1, decl1);
5668 /* Optionally warn of any def with no previous declaration
5669 if the function has already been used. */
5670 else if (warn_missing_declarations
5671 && old_decl != 0 && TREE_USED (old_decl)
5672 && C_DECL_IMPLICIT (old_decl))
5673 warning ("%J`%D' was used with no declaration before its definition",
5674 decl1, decl1);
5676 /* This is a definition, not a reference.
5677 So normally clear DECL_EXTERNAL.
5678 However, `extern inline' acts like a declaration
5679 except for defining how to inline. So set DECL_EXTERNAL in that case. */
5680 DECL_EXTERNAL (decl1) = current_extern_inline;
5682 /* This function exists in static storage.
5683 (This does not mean `static' in the C sense!) */
5684 TREE_STATIC (decl1) = 1;
5686 /* A nested function is not global. */
5687 if (current_function_decl != 0)
5688 TREE_PUBLIC (decl1) = 0;
5690 #ifdef ENABLE_CHECKING
5691 /* This is the earliest point at which we might know the assembler
5692 name of the function. Thus, if it's set before this, die horribly. */
5693 if (DECL_ASSEMBLER_NAME_SET_P (decl1))
5694 abort ();
5695 #endif
5697 /* If #pragma weak was used, mark the decl weak now. */
5698 if (current_scope == file_scope)
5699 maybe_apply_pragma_weak (decl1);
5701 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
5702 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
5704 tree args;
5705 int argct = 0;
5707 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
5708 != integer_type_node)
5709 pedwarn ("%Jreturn type of '%D' is not `int'", decl1, decl1);
5711 for (args = TYPE_ARG_TYPES (TREE_TYPE (decl1)); args;
5712 args = TREE_CHAIN (args))
5714 tree type = args ? TREE_VALUE (args) : 0;
5716 if (type == void_type_node)
5717 break;
5719 ++argct;
5720 switch (argct)
5722 case 1:
5723 if (TYPE_MAIN_VARIANT (type) != integer_type_node)
5724 pedwarn ("%Jfirst argument of '%D' should be `int'",
5725 decl1, decl1);
5726 break;
5728 case 2:
5729 if (TREE_CODE (type) != POINTER_TYPE
5730 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
5731 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
5732 != char_type_node))
5733 pedwarn ("%Jsecond argument of '%D' should be 'char **'",
5734 decl1, decl1);
5735 break;
5737 case 3:
5738 if (TREE_CODE (type) != POINTER_TYPE
5739 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
5740 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
5741 != char_type_node))
5742 pedwarn ("%Jthird argument of '%D' should probably be "
5743 "'char **'", decl1, decl1);
5744 break;
5748 /* It is intentional that this message does not mention the third
5749 argument because it's only mentioned in an appendix of the
5750 standard. */
5751 if (argct > 0 && (argct < 2 || argct > 3))
5752 pedwarn ("%J'%D' takes only zero or two arguments", decl1, decl1);
5754 if (! TREE_PUBLIC (decl1))
5755 pedwarn ("%J'%D' is normally a non-static function", decl1, decl1);
5758 /* Record the decl so that the function name is defined.
5759 If we already have a decl for this name, and it is a FUNCTION_DECL,
5760 use the old decl. */
5762 current_function_decl = pushdecl (decl1);
5764 push_scope ();
5765 declare_parm_level ();
5767 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
5768 /* Promote the value to int before returning it. */
5769 if (c_promoting_integer_type_p (restype))
5771 /* It retains unsignedness if not really getting wider. */
5772 if (TYPE_UNSIGNED (restype)
5773 && (TYPE_PRECISION (restype)
5774 == TYPE_PRECISION (integer_type_node)))
5775 restype = unsigned_type_node;
5776 else
5777 restype = integer_type_node;
5779 DECL_RESULT (current_function_decl)
5780 = build_decl (RESULT_DECL, NULL_TREE, restype);
5782 start_fname_decls ();
5784 return 1;
5787 /* Subroutine of store_parm_decls which handles new-style function
5788 definitions (prototype format). The parms already have decls, so we
5789 need only record them as in effect and complain if any redundant
5790 old-style parm decls were written. */
5791 static void
5792 store_parm_decls_newstyle (tree fndecl, tree arg_info)
5794 tree decl;
5795 tree parms = ARG_INFO_PARMS (arg_info);
5796 tree tags = ARG_INFO_TAGS (arg_info);
5797 tree others = ARG_INFO_OTHERS (arg_info);
5799 if (current_scope->bindings)
5801 error ("%Jold-style parameter declarations in prototyped "
5802 "function definition", fndecl);
5804 /* Get rid of the old-style declarations. */
5805 pop_scope ();
5806 push_scope ();
5808 /* Don't issue this warning for nested functions, and don't issue this
5809 warning if we got here because ARG_INFO_TYPES was error_mark_node
5810 (this happens when a function definition has just an ellipsis in
5811 its parameter list). */
5812 else if (warn_traditional && !in_system_header && !current_function_scope
5813 && ARG_INFO_TYPES (arg_info) != error_mark_node)
5814 warning ("%Jtraditional C rejects ISO C style function definitions",
5815 fndecl);
5817 /* Now make all the parameter declarations visible in the function body.
5818 We can bypass most of the grunt work of pushdecl. */
5819 for (decl = parms; decl; decl = TREE_CHAIN (decl))
5821 DECL_CONTEXT (decl) = current_function_decl;
5822 if (DECL_NAME (decl))
5823 bind (DECL_NAME (decl), decl, current_scope);
5824 else
5825 error ("%Jparameter name omitted", decl);
5828 /* Record the parameter list in the function declaration. */
5829 DECL_ARGUMENTS (fndecl) = parms;
5831 /* Now make all the ancillary declarations visible, likewise. */
5832 for (decl = others; decl; decl = TREE_CHAIN (decl))
5834 DECL_CONTEXT (decl) = current_function_decl;
5835 if (DECL_NAME (decl))
5836 bind (DECL_NAME (decl), decl, current_scope);
5839 /* And all the tag declarations. */
5840 for (decl = tags; decl; decl = TREE_CHAIN (decl))
5841 if (TREE_PURPOSE (decl))
5842 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope);
5845 /* Subroutine of store_parm_decls which handles old-style function
5846 definitions (separate parameter list and declarations). */
5848 static void
5849 store_parm_decls_oldstyle (tree fndecl, tree arg_info)
5851 struct c_binding *b;
5852 tree parm, decl, last;
5853 tree parmids = ARG_INFO_PARMS (arg_info);
5855 /* We use DECL_WEAK as a flag to show which parameters have been
5856 seen already, since it is not used on PARM_DECL. */
5857 #ifdef ENABLE_CHECKING
5858 for (b = current_scope->bindings; b; b = b->prev)
5859 if (TREE_CODE (b->decl) == PARM_DECL && DECL_WEAK (b->decl))
5860 abort ();
5861 #endif
5863 if (warn_old_style_definition && !in_system_header)
5864 warning ("%Jold-style function definition", fndecl);
5866 /* Match each formal parameter name with its declaration. Save each
5867 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
5868 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
5870 if (TREE_VALUE (parm) == 0)
5872 error ("%Jparameter name missing from parameter list", fndecl);
5873 TREE_PURPOSE (parm) = 0;
5874 continue;
5877 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
5878 if (b && b->contour == current_scope)
5880 decl = b->decl;
5881 /* If we got something other than a PARM_DECL it is an error. */
5882 if (TREE_CODE (decl) != PARM_DECL)
5883 error ("%J'%D' declared as a non-parameter", decl, decl);
5884 /* If the declaration is already marked, we have a duplicate
5885 name. Complain and ignore the duplicate. */
5886 else if (DECL_WEAK (decl))
5888 error ("%Jmultiple parameters named '%D'", decl, decl);
5889 TREE_PURPOSE (parm) = 0;
5890 continue;
5892 /* If the declaration says "void", complain and turn it into
5893 an int. */
5894 else if (VOID_TYPE_P (TREE_TYPE (decl)))
5896 error ("%Jparameter '%D' declared with void type", decl, decl);
5897 TREE_TYPE (decl) = integer_type_node;
5898 DECL_ARG_TYPE (decl) = integer_type_node;
5899 layout_decl (decl, 0);
5902 /* If no declaration found, default to int. */
5903 else
5905 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
5906 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
5907 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
5908 pushdecl (decl);
5910 if (flag_isoc99)
5911 pedwarn ("%Jtype of '%D' defaults to 'int'", decl, decl);
5912 else if (extra_warnings)
5913 warning ("%Jtype of '%D' defaults to 'int'", decl, decl);
5916 TREE_PURPOSE (parm) = decl;
5917 DECL_WEAK (decl) = 1;
5920 /* Now examine the parms chain for incomplete declarations
5921 and declarations with no corresponding names. */
5923 for (b = current_scope->bindings; b; b = b->prev)
5925 parm = b->decl;
5926 if (TREE_CODE (parm) != PARM_DECL)
5927 continue;
5929 if (!COMPLETE_TYPE_P (TREE_TYPE (parm)))
5931 error ("%Jparameter '%D' has incomplete type", parm, parm);
5932 TREE_TYPE (parm) = error_mark_node;
5935 if (! DECL_WEAK (parm))
5937 error ("%Jdeclaration for parameter '%D' but no such parameter",
5938 parm, parm);
5940 /* Pretend the parameter was not missing.
5941 This gets us to a standard state and minimizes
5942 further error messages. */
5943 parmids = chainon (parmids, tree_cons (parm, 0, 0));
5947 /* Chain the declarations together in the order of the list of
5948 names. Store that chain in the function decl, replacing the
5949 list of names. Update the current scope to match. */
5950 DECL_ARGUMENTS (fndecl) = 0;
5952 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
5953 if (TREE_PURPOSE (parm))
5954 break;
5955 if (parm && TREE_PURPOSE (parm))
5957 last = TREE_PURPOSE (parm);
5958 DECL_ARGUMENTS (fndecl) = last;
5959 DECL_WEAK (last) = 0;
5961 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
5962 if (TREE_PURPOSE (parm))
5964 TREE_CHAIN (last) = TREE_PURPOSE (parm);
5965 last = TREE_PURPOSE (parm);
5966 DECL_WEAK (last) = 0;
5968 TREE_CHAIN (last) = 0;
5971 /* If there was a previous prototype,
5972 set the DECL_ARG_TYPE of each argument according to
5973 the type previously specified, and report any mismatches. */
5975 if (TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
5977 tree type;
5978 for (parm = DECL_ARGUMENTS (fndecl),
5979 type = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
5980 parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
5981 != void_type_node));
5982 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
5984 if (parm == 0 || type == 0
5985 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
5987 error ("number of arguments doesn't match prototype");
5988 error ("%Hprototype declaration",
5989 &current_function_prototype_locus);
5990 break;
5992 /* Type for passing arg must be consistent with that
5993 declared for the arg. ISO C says we take the unqualified
5994 type for parameters declared with qualified type. */
5995 if (! comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
5996 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
5998 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
5999 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6001 /* Adjust argument to match prototype. E.g. a previous
6002 `int foo(float);' prototype causes
6003 `int foo(x) float x; {...}' to be treated like
6004 `int foo(float x) {...}'. This is particularly
6005 useful for argument types like uid_t. */
6006 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6008 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6009 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6010 && TYPE_PRECISION (TREE_TYPE (parm))
6011 < TYPE_PRECISION (integer_type_node))
6012 DECL_ARG_TYPE (parm) = integer_type_node;
6014 if (pedantic)
6016 pedwarn ("promoted argument '%D' "
6017 "doesn't match prototype", parm);
6018 pedwarn ("%Hprototype declaration",
6019 &current_function_prototype_locus);
6022 else
6024 error ("argument '%D' doesn't match prototype", parm);
6025 error ("%Hprototype declaration",
6026 &current_function_prototype_locus);
6030 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6033 /* Otherwise, create a prototype that would match. */
6035 else
6037 tree actual = 0, last = 0, type;
6039 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6041 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6042 if (last)
6043 TREE_CHAIN (last) = type;
6044 else
6045 actual = type;
6046 last = type;
6048 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6049 if (last)
6050 TREE_CHAIN (last) = type;
6051 else
6052 actual = type;
6054 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6055 of the type of this function, but we need to avoid having this
6056 affect the types of other similarly-typed functions, so we must
6057 first force the generation of an identical (but separate) type
6058 node for the relevant function type. The new node we create
6059 will be a variant of the main variant of the original function
6060 type. */
6062 TREE_TYPE (fndecl) = build_type_copy (TREE_TYPE (fndecl));
6064 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6068 /* A subroutine of store_parm_decls called via walk_tree. Mark all
6069 decls non-local. */
6071 static tree
6072 set_decl_nonlocal (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
6074 tree t = *tp;
6076 if (DECL_P (t))
6078 DECL_NONLOCAL (t) = 1;
6079 *walk_subtrees = 0;
6081 else if (TYPE_P (t))
6082 *walk_subtrees = 0;
6084 return NULL;
6087 /* Store the parameter declarations into the current function declaration.
6088 This is called after parsing the parameter declarations, before
6089 digesting the body of the function.
6091 For an old-style definition, construct a prototype out of the old-style
6092 parameter declarations and inject it into the function's type. */
6094 void
6095 store_parm_decls (void)
6097 tree fndecl = current_function_decl;
6099 /* The function containing FNDECL, if any. */
6100 tree context = decl_function_context (fndecl);
6102 /* The argument information block for FNDECL. */
6103 tree arg_info = DECL_ARGUMENTS (fndecl);
6105 /* True if this definition is written with a prototype. Note:
6106 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6107 list in a function definition as equivalent to (void) -- an
6108 empty argument list specifies the function has no parameters,
6109 but only (void) sets up a prototype for future calls. */
6110 bool proto = ARG_INFO_TYPES (arg_info) != 0;
6112 if (proto)
6113 store_parm_decls_newstyle (fndecl, arg_info);
6114 else
6115 store_parm_decls_oldstyle (fndecl, arg_info);
6117 /* The next call to push_scope will be a function body. */
6119 next_is_function_body = true;
6121 /* Write a record describing this function definition to the prototypes
6122 file (if requested). */
6124 gen_aux_info_record (fndecl, 1, 0, proto);
6126 /* Initialize the RTL code for the function. */
6127 allocate_struct_function (fndecl);
6129 /* Begin the statement tree for this function. */
6130 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6132 /* If this is a nested function, save away the sizes of any
6133 variable-size types so that we can expand them when generating
6134 RTL. */
6135 if (context)
6137 tree t;
6139 DECL_LANG_SPECIFIC (fndecl)->pending_sizes
6140 = nreverse (get_pending_sizes ());
6141 for (t = DECL_LANG_SPECIFIC (fndecl)->pending_sizes;
6143 t = TREE_CHAIN (t))
6145 /* We will have a nonlocal use of whatever variables are
6146 buried inside here. */
6147 walk_tree (&TREE_OPERAND (TREE_VALUE (t), 0),
6148 set_decl_nonlocal, NULL, NULL);
6150 SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = context;
6154 /* Even though we're inside a function body, we still don't want to
6155 call expand_expr to calculate the size of a variable-sized array.
6156 We haven't necessarily assigned RTL to all variables yet, so it's
6157 not safe to try to expand expressions involving them. */
6158 cfun->x_dont_save_pending_sizes_p = 1;
6161 /* Give FNDECL and all its nested functions to cgraph for compilation. */
6163 static void
6164 c_finalize (tree fndecl)
6166 struct cgraph_node *cgn;
6168 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6169 c_warn_unused_result (&DECL_SAVED_TREE (fndecl));
6171 /* ??? Objc emits functions after finalizing the compilation unit.
6172 This should be cleaned up later and this conditional removed. */
6173 if (cgraph_global_info_ready)
6175 c_expand_body (fndecl);
6176 return;
6179 /* Finalize all nested functions now. */
6180 cgn = cgraph_node (fndecl);
6181 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6182 c_finalize (cgn->decl);
6184 cgraph_finalize_function (fndecl, false);
6187 /* Finish up a function declaration and compile that function
6188 all the way to assembler language output. The free the storage
6189 for the function definition.
6191 This is called after parsing the body of the function definition. */
6193 void
6194 finish_function (void)
6196 tree fndecl = current_function_decl;
6198 if (TREE_CODE (fndecl) == FUNCTION_DECL
6199 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6201 tree args = DECL_ARGUMENTS (fndecl);
6202 for (; args; args = TREE_CHAIN (args))
6204 tree type = TREE_TYPE (args);
6205 if (INTEGRAL_TYPE_P (type)
6206 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6207 DECL_ARG_TYPE (args) = integer_type_node;
6211 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6212 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6214 /* Must mark the RESULT_DECL as being in this function. */
6216 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6217 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6219 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6221 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6222 != integer_type_node)
6224 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6225 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6226 if (!warn_main)
6227 pedwarn ("%Jreturn type of '%D' is not `int'", fndecl, fndecl);
6229 else
6231 if (flag_isoc99)
6232 c_finish_return (integer_zero_node);
6236 /* Tie off the statement tree for this function. */
6237 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6239 finish_fname_decls ();
6241 /* Complain if there's just no return statement. */
6242 if (warn_return_type
6243 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6244 && !current_function_returns_value && !current_function_returns_null
6245 /* Don't complain if we abort. */
6246 && !current_function_returns_abnormally
6247 /* Don't warn for main(). */
6248 && !MAIN_NAME_P (DECL_NAME (fndecl))
6249 /* Or if they didn't actually specify a return type. */
6250 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6251 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6252 inline function, as we might never be compiled separately. */
6253 && DECL_INLINE (fndecl))
6254 warning ("no return statement in function returning non-void");
6256 /* With just -Wextra, complain only if function returns both with
6257 and without a value. */
6258 if (extra_warnings
6259 && current_function_returns_value
6260 && current_function_returns_null)
6261 warning ("this function may return with or without a value");
6263 /* Store the end of the function, so that we get good line number
6264 info for the epilogue. */
6265 cfun->function_end_locus = input_location;
6267 /* If we don't have ctors/dtors sections, and this is a static
6268 constructor or destructor, it must be recorded now. */
6269 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6270 && !targetm.have_ctors_dtors)
6271 static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
6272 if (DECL_STATIC_DESTRUCTOR (fndecl)
6273 && !targetm.have_ctors_dtors)
6274 static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
6276 /* Genericize before inlining. Delay genericizing nested functions
6277 until their parent function is genericized. Since finalizing
6278 requires GENERIC, delay that as well. */
6280 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6282 if (!decl_function_context (fndecl))
6284 c_genericize (fndecl);
6285 lower_nested_functions (fndecl);
6286 c_finalize (fndecl);
6288 else
6290 /* Register this function with cgraph just far enough to get it
6291 added to our parent's nested function list. Handy, since the
6292 C front end doesn't have such a list. */
6293 (void) cgraph_node (fndecl);
6297 /* We're leaving the context of this function, so zap cfun.
6298 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6299 tree_rest_of_compilation. */
6300 cfun = NULL;
6301 current_function_decl = NULL;
6304 /* Generate the RTL for the body of FNDECL. */
6306 void
6307 c_expand_body (tree fndecl)
6310 if (!DECL_INITIAL (fndecl)
6311 || DECL_INITIAL (fndecl) == error_mark_node)
6312 return;
6314 tree_rest_of_compilation (fndecl, false);
6316 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6317 && targetm.have_ctors_dtors)
6318 targetm.asm_out.constructor (XEXP (DECL_RTL (fndecl), 0),
6319 DEFAULT_INIT_PRIORITY);
6320 if (DECL_STATIC_DESTRUCTOR (fndecl)
6321 && targetm.have_ctors_dtors)
6322 targetm.asm_out.destructor (XEXP (DECL_RTL (fndecl), 0),
6323 DEFAULT_INIT_PRIORITY);
6326 /* Check the declarations given in a for-loop for satisfying the C99
6327 constraints. */
6328 void
6329 check_for_loop_decls (void)
6331 struct c_binding *b;
6333 if (!flag_isoc99)
6335 /* If we get here, declarations have been used in a for loop without
6336 the C99 for loop scope. This doesn't make much sense, so don't
6337 allow it. */
6338 error ("'for' loop initial declaration used outside C99 mode");
6339 return;
6341 /* C99 subclause 6.8.5 paragraph 3:
6343 [#3] The declaration part of a for statement shall only
6344 declare identifiers for objects having storage class auto or
6345 register.
6347 It isn't clear whether, in this sentence, "identifiers" binds to
6348 "shall only declare" or to "objects" - that is, whether all identifiers
6349 declared must be identifiers for objects, or whether the restriction
6350 only applies to those that are. (A question on this in comp.std.c
6351 in November 2000 received no answer.) We implement the strictest
6352 interpretation, to avoid creating an extension which later causes
6353 problems. */
6355 for (b = current_scope->bindings; b; b = b->prev)
6357 tree id = b->id;
6358 tree decl = b->decl;
6360 if (!id)
6361 continue;
6363 switch (TREE_CODE (decl))
6365 case VAR_DECL:
6366 if (TREE_STATIC (decl))
6367 error ("%Jdeclaration of static variable '%D' in 'for' loop "
6368 "initial declaration", decl, decl);
6369 else if (DECL_EXTERNAL (decl))
6370 error ("%Jdeclaration of 'extern' variable '%D' in 'for' loop "
6371 "initial declaration", decl, decl);
6372 break;
6374 case RECORD_TYPE:
6375 error ("'struct %E' declared in 'for' loop initial declaration", id);
6376 break;
6377 case UNION_TYPE:
6378 error ("'union %E' declared in 'for' loop initial declaration", id);
6379 break;
6380 case ENUMERAL_TYPE:
6381 error ("'enum %E' declared in 'for' loop initial declaration", id);
6382 break;
6383 default:
6384 error ("%Jdeclaration of non-variable '%D' in 'for' loop "
6385 "initial declaration", decl, decl);
6390 /* Save and reinitialize the variables
6391 used during compilation of a C function. */
6393 void
6394 c_push_function_context (struct function *f)
6396 struct language_function *p;
6397 p = ggc_alloc (sizeof (struct language_function));
6398 f->language = p;
6400 p->base.x_stmt_tree = c_stmt_tree;
6401 p->x_break_label = c_break_label;
6402 p->x_cont_label = c_cont_label;
6403 p->x_switch_stack = c_switch_stack;
6404 p->returns_value = current_function_returns_value;
6405 p->returns_null = current_function_returns_null;
6406 p->returns_abnormally = current_function_returns_abnormally;
6407 p->warn_about_return_type = warn_about_return_type;
6408 p->extern_inline = current_extern_inline;
6411 /* Restore the variables used during compilation of a C function. */
6413 void
6414 c_pop_function_context (struct function *f)
6416 struct language_function *p = f->language;
6418 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6419 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6421 /* Stop pointing to the local nodes about to be freed. */
6422 /* But DECL_INITIAL must remain nonzero so we know this
6423 was an actual function definition. */
6424 DECL_INITIAL (current_function_decl) = error_mark_node;
6425 DECL_ARGUMENTS (current_function_decl) = 0;
6428 c_stmt_tree = p->base.x_stmt_tree;
6429 c_break_label = p->x_break_label;
6430 c_cont_label = p->x_cont_label;
6431 c_switch_stack = p->x_switch_stack;
6432 current_function_returns_value = p->returns_value;
6433 current_function_returns_null = p->returns_null;
6434 current_function_returns_abnormally = p->returns_abnormally;
6435 warn_about_return_type = p->warn_about_return_type;
6436 current_extern_inline = p->extern_inline;
6438 f->language = NULL;
6441 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6443 void
6444 c_dup_lang_specific_decl (tree decl)
6446 struct lang_decl *ld;
6448 if (!DECL_LANG_SPECIFIC (decl))
6449 return;
6451 ld = ggc_alloc (sizeof (struct lang_decl));
6452 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
6453 DECL_LANG_SPECIFIC (decl) = ld;
6456 /* The functions below are required for functionality of doing
6457 function at once processing in the C front end. Currently these
6458 functions are not called from anywhere in the C front end, but as
6459 these changes continue, that will change. */
6461 /* Returns nonzero if the current statement is a full expression,
6462 i.e. temporaries created during that statement should be destroyed
6463 at the end of the statement. */
6466 stmts_are_full_exprs_p (void)
6468 return 0;
6471 /* Returns the stmt_tree (if any) to which statements are currently
6472 being added. If there is no active statement-tree, NULL is
6473 returned. */
6475 stmt_tree
6476 current_stmt_tree (void)
6478 return &c_stmt_tree;
6481 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
6482 C. */
6485 anon_aggr_type_p (tree node ATTRIBUTE_UNUSED)
6487 return 0;
6490 /* Dummy function in place of callback used by C++. */
6492 void
6493 extract_interface_info (void)
6497 /* Return the global value of T as a symbol. */
6499 tree
6500 identifier_global_value (tree t)
6502 struct c_binding *b;
6504 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
6505 if (b->contour == file_scope || b->contour == external_scope)
6506 return b->decl;
6508 return 0;
6511 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
6512 otherwise the name is found in ridpointers from RID_INDEX. */
6514 void
6515 record_builtin_type (enum rid rid_index, const char *name, tree type)
6517 tree id;
6518 if (name == 0)
6519 id = ridpointers[(int) rid_index];
6520 else
6521 id = get_identifier (name);
6522 pushdecl (build_decl (TYPE_DECL, id, type));
6525 /* Build the void_list_node (void_type_node having been created). */
6526 tree
6527 build_void_list_node (void)
6529 tree t = build_tree_list (NULL_TREE, void_type_node);
6530 return t;
6533 /* Return something to represent absolute declarators containing a *.
6534 TARGET is the absolute declarator that the * contains.
6535 TYPE_QUALS_ATTRS is a list of modifiers such as const or volatile
6536 to apply to the pointer type, represented as identifiers, possible mixed
6537 with attributes.
6539 We return an INDIRECT_REF whose "contents" are TARGET (inside a TREE_LIST,
6540 if attributes are present) and whose type is the modifier list. */
6542 tree
6543 make_pointer_declarator (tree type_quals_attrs, tree target)
6545 tree quals, attrs;
6546 tree itarget = target;
6547 split_specs_attrs (type_quals_attrs, &quals, &attrs);
6548 if (attrs != NULL_TREE)
6549 itarget = tree_cons (attrs, target, NULL_TREE);
6550 return build1 (INDIRECT_REF, quals, itarget);
6553 /* A wrapper around lhd_set_decl_assembler_name that gives static
6554 variables their C names if they are at file scope and only one
6555 translation unit is being compiled, for backwards compatibility
6556 with certain bizarre assembler hacks (like crtstuff.c). */
6558 void
6559 c_static_assembler_name (tree decl)
6561 if (num_in_fnames == 1
6562 && !TREE_PUBLIC (decl) && DECL_CONTEXT (decl)
6563 && TREE_CODE (DECL_CONTEXT (decl)) == TRANSLATION_UNIT_DECL)
6564 SET_DECL_ASSEMBLER_NAME (decl, DECL_NAME (decl));
6565 else
6566 lhd_set_decl_assembler_name (decl);
6569 /* Perform final processing on file-scope data. */
6570 static void
6571 c_write_global_declarations_1 (tree globals)
6573 size_t len = list_length (globals);
6574 tree *vec = xmalloc (sizeof (tree) * len);
6575 size_t i;
6576 tree decl;
6578 /* Process the decls in the order they were written. */
6579 for (i = 0, decl = globals; i < len; i++, decl = TREE_CHAIN (decl))
6580 vec[i] = decl;
6582 wrapup_global_declarations (vec, len);
6583 check_global_declarations (vec, len);
6585 free (vec);
6588 void
6589 c_write_global_declarations (void)
6591 tree t;
6593 /* We don't want to do this if generating a PCH. */
6594 if (pch_file)
6595 return;
6597 /* Process all file scopes in this compilation. */
6598 for (t = all_translation_units; t; t = TREE_CHAIN (t))
6599 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
6601 /* Now do the same for the externals scope. */
6602 t = pop_scope ();
6603 if (t)
6604 c_write_global_declarations_1 (BLOCK_VARS (t));
6607 #include "gt-c-decl.h"