mips.c (mips16_copy_fpr_return_value): New function, split out from...
[official-gcc.git] / gcc / c-decl.c
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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, 2005, 2006, 2007 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 3, 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 COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Process declarations and symbol lookup for C front end.
22 Also constructs types; the standard scalar types at initialization,
23 and structure, union, array and enum types when they are declared. */
25 /* ??? not all decl nodes are given the most useful possible
26 line numbers. For example, the CONST_DECLs for enum values. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "input.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"
62 #include "pointer-set.h"
64 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
65 enum decl_context
66 { NORMAL, /* Ordinary declaration */
67 FUNCDEF, /* Function definition */
68 PARM, /* Declaration of parm before function body */
69 FIELD, /* Declaration inside struct or union */
70 TYPENAME}; /* Typename (inside cast or sizeof) */
72 /* States indicating how grokdeclarator() should handle declspecs marked
73 with __attribute__((deprecated)). An object declared as
74 __attribute__((deprecated)) suppresses warnings of uses of other
75 deprecated items. */
77 enum deprecated_states {
78 DEPRECATED_NORMAL,
79 DEPRECATED_SUPPRESS
83 /* Nonzero if we have seen an invalid cross reference
84 to a struct, union, or enum, but not yet printed the message. */
85 tree pending_invalid_xref;
87 /* File and line to appear in the eventual error message. */
88 location_t pending_invalid_xref_location;
90 /* True means we've initialized exception handling. */
91 bool c_eh_initialized_p;
93 /* The file and line that the prototype came from if this is an
94 old-style definition; used for diagnostics in
95 store_parm_decls_oldstyle. */
97 static location_t current_function_prototype_locus;
99 /* Whether this prototype was built-in. */
101 static bool current_function_prototype_built_in;
103 /* The argument type information of this prototype. */
105 static tree current_function_prototype_arg_types;
107 /* The argument information structure for the function currently being
108 defined. */
110 static struct c_arg_info *current_function_arg_info;
112 /* The obstack on which parser and related data structures, which are
113 not live beyond their top-level declaration or definition, are
114 allocated. */
115 struct obstack parser_obstack;
117 /* The current statement tree. */
119 static GTY(()) struct stmt_tree_s c_stmt_tree;
121 /* State saving variables. */
122 tree c_break_label;
123 tree c_cont_label;
125 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
126 included in this invocation. Note that the current translation
127 unit is not included in this list. */
129 static GTY(()) tree all_translation_units;
131 /* A list of decls to be made automatically visible in each file scope. */
132 static GTY(()) tree visible_builtins;
134 /* Set to 0 at beginning of a function definition, set to 1 if
135 a return statement that specifies a return value is seen. */
137 int current_function_returns_value;
139 /* Set to 0 at beginning of a function definition, set to 1 if
140 a return statement with no argument is seen. */
142 int current_function_returns_null;
144 /* Set to 0 at beginning of a function definition, set to 1 if
145 a call to a noreturn function is seen. */
147 int current_function_returns_abnormally;
149 /* Set to nonzero by `grokdeclarator' for a function
150 whose return type is defaulted, if warnings for this are desired. */
152 static int warn_about_return_type;
154 /* Nonzero when the current toplevel function contains a declaration
155 of a nested function which is never defined. */
157 static bool undef_nested_function;
159 /* True means global_bindings_p should return false even if the scope stack
160 says we are in file scope. */
161 bool c_override_global_bindings_to_false;
164 /* Each c_binding structure describes one binding of an identifier to
165 a decl. All the decls in a scope - irrespective of namespace - are
166 chained together by the ->prev field, which (as the name implies)
167 runs in reverse order. All the decls in a given namespace bound to
168 a given identifier are chained by the ->shadowed field, which runs
169 from inner to outer scopes.
171 The ->decl field usually points to a DECL node, but there are two
172 exceptions. In the namespace of type tags, the bound entity is a
173 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
174 identifier is encountered, it is bound to error_mark_node to
175 suppress further errors about that identifier in the current
176 function.
178 The ->type field stores the type of the declaration in this scope;
179 if NULL, the type is the type of the ->decl field. This is only of
180 relevance for objects with external or internal linkage which may
181 be redeclared in inner scopes, forming composite types that only
182 persist for the duration of those scopes. In the external scope,
183 this stores the composite of all the types declared for this
184 object, visible or not. The ->inner_comp field (used only at file
185 scope) stores whether an incomplete array type at file scope was
186 completed at an inner scope to an array size other than 1.
188 The depth field is copied from the scope structure that holds this
189 decl. It is used to preserve the proper ordering of the ->shadowed
190 field (see bind()) and also for a handful of special-case checks.
191 Finally, the invisible bit is true for a decl which should be
192 ignored for purposes of normal name lookup, and the nested bit is
193 true for a decl that's been bound a second time in an inner scope;
194 in all such cases, the binding in the outer scope will have its
195 invisible bit true. */
197 struct c_binding GTY((chain_next ("%h.prev")))
199 tree decl; /* the decl bound */
200 tree type; /* the type in this scope */
201 tree id; /* the identifier it's bound to */
202 struct c_binding *prev; /* the previous decl in this scope */
203 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
204 unsigned int depth : 28; /* depth of this scope */
205 BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
206 BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
207 BOOL_BITFIELD inner_comp : 1; /* incomplete array completed in inner scope */
208 /* one free bit */
210 #define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
211 #define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
212 #define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
213 #define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
215 #define I_SYMBOL_BINDING(node) \
216 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->symbol_binding)
217 #define I_SYMBOL_DECL(node) \
218 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
220 #define I_TAG_BINDING(node) \
221 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->tag_binding)
222 #define I_TAG_DECL(node) \
223 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
225 #define I_LABEL_BINDING(node) \
226 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->label_binding)
227 #define I_LABEL_DECL(node) \
228 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
230 /* Each C symbol points to three linked lists of c_binding structures.
231 These describe the values of the identifier in the three different
232 namespaces defined by the language. */
234 struct lang_identifier GTY(())
236 struct c_common_identifier common_id;
237 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
238 struct c_binding *tag_binding; /* struct/union/enum tags */
239 struct c_binding *label_binding; /* labels */
242 /* Validate c-lang.c's assumptions. */
243 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
244 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
246 /* The resulting tree type. */
248 union lang_tree_node
249 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
250 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *) TYPE_NEXT_VARIANT (&%h.generic) : ((union lang_tree_node *) GENERIC_NEXT (&%h.generic))")))
252 union tree_node GTY ((tag ("0"),
253 desc ("tree_node_structure (&%h)")))
254 generic;
255 struct lang_identifier GTY ((tag ("1"))) identifier;
258 /* Each c_scope structure describes the complete contents of one
259 scope. Four scopes are distinguished specially: the innermost or
260 current scope, the innermost function scope, the file scope (always
261 the second to outermost) and the outermost or external scope.
263 Most declarations are recorded in the current scope.
265 All normal label declarations are recorded in the innermost
266 function scope, as are bindings of undeclared identifiers to
267 error_mark_node. (GCC permits nested functions as an extension,
268 hence the 'innermost' qualifier.) Explicitly declared labels
269 (using the __label__ extension) appear in the current scope.
271 Being in the file scope (current_scope == file_scope) causes
272 special behavior in several places below. Also, under some
273 conditions the Objective-C front end records declarations in the
274 file scope even though that isn't the current scope.
276 All declarations with external linkage are recorded in the external
277 scope, even if they aren't visible there; this models the fact that
278 such declarations are visible to the entire program, and (with a
279 bit of cleverness, see pushdecl) allows diagnosis of some violations
280 of C99 6.2.2p7 and 6.2.7p2:
282 If, within the same translation unit, the same identifier appears
283 with both internal and external linkage, the behavior is
284 undefined.
286 All declarations that refer to the same object or function shall
287 have compatible type; otherwise, the behavior is undefined.
289 Initially only the built-in declarations, which describe compiler
290 intrinsic functions plus a subset of the standard library, are in
291 this scope.
293 The order of the blocks list matters, and it is frequently appended
294 to. To avoid having to walk all the way to the end of the list on
295 each insertion, or reverse the list later, we maintain a pointer to
296 the last list entry. (FIXME: It should be feasible to use a reversed
297 list here.)
299 The bindings list is strictly in reverse order of declarations;
300 pop_scope relies on this. */
303 struct c_scope GTY((chain_next ("%h.outer")))
305 /* The scope containing this one. */
306 struct c_scope *outer;
308 /* The next outermost function scope. */
309 struct c_scope *outer_function;
311 /* All bindings in this scope. */
312 struct c_binding *bindings;
314 /* For each scope (except the global one), a chain of BLOCK nodes
315 for all the scopes that were entered and exited one level down. */
316 tree blocks;
317 tree blocks_last;
319 /* The depth of this scope. Used to keep the ->shadowed chain of
320 bindings sorted innermost to outermost. */
321 unsigned int depth : 28;
323 /* True if we are currently filling this scope with parameter
324 declarations. */
325 BOOL_BITFIELD parm_flag : 1;
327 /* True if we saw [*] in this scope. Used to give an error messages
328 if these appears in a function definition. */
329 BOOL_BITFIELD had_vla_unspec : 1;
331 /* True if we already complained about forward parameter decls
332 in this scope. This prevents double warnings on
333 foo (int a; int b; ...) */
334 BOOL_BITFIELD warned_forward_parm_decls : 1;
336 /* True if this is the outermost block scope of a function body.
337 This scope contains the parameters, the local variables declared
338 in the outermost block, and all the labels (except those in
339 nested functions, or declared at block scope with __label__). */
340 BOOL_BITFIELD function_body : 1;
342 /* True means make a BLOCK for this scope no matter what. */
343 BOOL_BITFIELD keep : 1;
346 /* The scope currently in effect. */
348 static GTY(()) struct c_scope *current_scope;
350 /* The innermost function scope. Ordinary (not explicitly declared)
351 labels, bindings to error_mark_node, and the lazily-created
352 bindings of __func__ and its friends get this scope. */
354 static GTY(()) struct c_scope *current_function_scope;
356 /* The C file scope. This is reset for each input translation unit. */
358 static GTY(()) struct c_scope *file_scope;
360 /* The outermost scope. This is used for all declarations with
361 external linkage, and only these, hence the name. */
363 static GTY(()) struct c_scope *external_scope;
365 /* A chain of c_scope structures awaiting reuse. */
367 static GTY((deletable)) struct c_scope *scope_freelist;
369 /* A chain of c_binding structures awaiting reuse. */
371 static GTY((deletable)) struct c_binding *binding_freelist;
373 /* Append VAR to LIST in scope SCOPE. */
374 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
375 struct c_scope *s_ = (scope); \
376 tree d_ = (decl); \
377 if (s_->list##_last) \
378 TREE_CHAIN (s_->list##_last) = d_; \
379 else \
380 s_->list = d_; \
381 s_->list##_last = d_; \
382 } while (0)
384 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
385 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
386 struct c_scope *t_ = (tscope); \
387 struct c_scope *f_ = (fscope); \
388 if (t_->to##_last) \
389 TREE_CHAIN (t_->to##_last) = f_->from; \
390 else \
391 t_->to = f_->from; \
392 t_->to##_last = f_->from##_last; \
393 } while (0)
395 /* True means unconditionally make a BLOCK for the next scope pushed. */
397 static bool keep_next_level_flag;
399 /* True means the next call to push_scope will be the outermost scope
400 of a function body, so do not push a new scope, merely cease
401 expecting parameter decls. */
403 static bool next_is_function_body;
405 /* Forward declarations. */
406 static tree lookup_name_in_scope (tree, struct c_scope *);
407 static tree c_make_fname_decl (tree, int);
408 static tree grokdeclarator (const struct c_declarator *,
409 struct c_declspecs *,
410 enum decl_context, bool, tree *, tree *,
411 enum deprecated_states);
412 static tree grokparms (struct c_arg_info *, bool);
413 static void layout_array_type (tree);
415 /* T is a statement. Add it to the statement-tree. This is the
416 C/ObjC version--C++ has a slightly different version of this
417 function. */
419 tree
420 add_stmt (tree t)
422 enum tree_code code = TREE_CODE (t);
424 if (CAN_HAVE_LOCATION_P (t) && code != LABEL_EXPR)
426 if (!EXPR_HAS_LOCATION (t))
427 SET_EXPR_LOCATION (t, input_location);
430 if (code == LABEL_EXPR || code == CASE_LABEL_EXPR)
431 STATEMENT_LIST_HAS_LABEL (cur_stmt_list) = 1;
433 /* Add T to the statement-tree. Non-side-effect statements need to be
434 recorded during statement expressions. */
435 append_to_statement_list_force (t, &cur_stmt_list);
437 return t;
441 void
442 c_print_identifier (FILE *file, tree node, int indent)
444 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
445 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
446 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
447 if (C_IS_RESERVED_WORD (node))
449 tree rid = ridpointers[C_RID_CODE (node)];
450 indent_to (file, indent + 4);
451 fprintf (file, "rid %p \"%s\"",
452 (void *) rid, IDENTIFIER_POINTER (rid));
456 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
457 which may be any of several kinds of DECL or TYPE or error_mark_node,
458 in the scope SCOPE. */
459 static void
460 bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
462 struct c_binding *b, **here;
464 if (binding_freelist)
466 b = binding_freelist;
467 binding_freelist = b->prev;
469 else
470 b = GGC_NEW (struct c_binding);
472 b->shadowed = 0;
473 b->decl = decl;
474 b->id = name;
475 b->depth = scope->depth;
476 b->invisible = invisible;
477 b->nested = nested;
478 b->inner_comp = 0;
480 b->type = 0;
482 b->prev = scope->bindings;
483 scope->bindings = b;
485 if (!name)
486 return;
488 switch (TREE_CODE (decl))
490 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
491 case ENUMERAL_TYPE:
492 case UNION_TYPE:
493 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
494 case VAR_DECL:
495 case FUNCTION_DECL:
496 case TYPE_DECL:
497 case CONST_DECL:
498 case PARM_DECL:
499 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
501 default:
502 gcc_unreachable ();
505 /* Locate the appropriate place in the chain of shadowed decls
506 to insert this binding. Normally, scope == current_scope and
507 this does nothing. */
508 while (*here && (*here)->depth > scope->depth)
509 here = &(*here)->shadowed;
511 b->shadowed = *here;
512 *here = b;
515 /* Clear the binding structure B, stick it on the binding_freelist,
516 and return the former value of b->prev. This is used by pop_scope
517 and get_parm_info to iterate destructively over all the bindings
518 from a given scope. */
519 static struct c_binding *
520 free_binding_and_advance (struct c_binding *b)
522 struct c_binding *prev = b->prev;
524 memset (b, 0, sizeof (struct c_binding));
525 b->prev = binding_freelist;
526 binding_freelist = b;
528 return prev;
532 /* Hook called at end of compilation to assume 1 elt
533 for a file-scope tentative array defn that wasn't complete before. */
535 void
536 c_finish_incomplete_decl (tree decl)
538 if (TREE_CODE (decl) == VAR_DECL)
540 tree type = TREE_TYPE (decl);
541 if (type != error_mark_node
542 && TREE_CODE (type) == ARRAY_TYPE
543 && !DECL_EXTERNAL (decl)
544 && TYPE_DOMAIN (type) == 0)
546 warning (0, "array %q+D assumed to have one element", decl);
548 complete_array_type (&TREE_TYPE (decl), NULL_TREE, true);
550 layout_decl (decl, 0);
555 /* The Objective-C front-end often needs to determine the current scope. */
557 void *
558 objc_get_current_scope (void)
560 return current_scope;
563 /* The following function is used only by Objective-C. It needs to live here
564 because it accesses the innards of c_scope. */
566 void
567 objc_mark_locals_volatile (void *enclosing_blk)
569 struct c_scope *scope;
570 struct c_binding *b;
572 for (scope = current_scope;
573 scope && scope != enclosing_blk;
574 scope = scope->outer)
576 for (b = scope->bindings; b; b = b->prev)
577 objc_volatilize_decl (b->decl);
579 /* Do not climb up past the current function. */
580 if (scope->function_body)
581 break;
585 /* Nonzero if we are currently in file scope. */
588 global_bindings_p (void)
590 return current_scope == file_scope && !c_override_global_bindings_to_false;
593 void
594 keep_next_level (void)
596 keep_next_level_flag = true;
599 /* Identify this scope as currently being filled with parameters. */
601 void
602 declare_parm_level (void)
604 current_scope->parm_flag = true;
607 void
608 push_scope (void)
610 if (next_is_function_body)
612 /* This is the transition from the parameters to the top level
613 of the function body. These are the same scope
614 (C99 6.2.1p4,6) so we do not push another scope structure.
615 next_is_function_body is set only by store_parm_decls, which
616 in turn is called when and only when we are about to
617 encounter the opening curly brace for the function body.
619 The outermost block of a function always gets a BLOCK node,
620 because the debugging output routines expect that each
621 function has at least one BLOCK. */
622 current_scope->parm_flag = false;
623 current_scope->function_body = true;
624 current_scope->keep = true;
625 current_scope->outer_function = current_function_scope;
626 current_function_scope = current_scope;
628 keep_next_level_flag = false;
629 next_is_function_body = false;
631 else
633 struct c_scope *scope;
634 if (scope_freelist)
636 scope = scope_freelist;
637 scope_freelist = scope->outer;
639 else
640 scope = GGC_CNEW (struct c_scope);
642 scope->keep = keep_next_level_flag;
643 scope->outer = current_scope;
644 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
646 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
647 possible. */
648 if (current_scope && scope->depth == 0)
650 scope->depth--;
651 sorry ("GCC supports only %u nested scopes", scope->depth);
654 current_scope = scope;
655 keep_next_level_flag = false;
659 /* Set the TYPE_CONTEXT of all of TYPE's variants to CONTEXT. */
661 static void
662 set_type_context (tree type, tree context)
664 for (type = TYPE_MAIN_VARIANT (type); type;
665 type = TYPE_NEXT_VARIANT (type))
666 TYPE_CONTEXT (type) = context;
669 /* Exit a scope. Restore the state of the identifier-decl mappings
670 that were in effect when this scope was entered. Return a BLOCK
671 node containing all the DECLs in this scope that are of interest
672 to debug info generation. */
674 tree
675 pop_scope (void)
677 struct c_scope *scope = current_scope;
678 tree block, context, p;
679 struct c_binding *b;
681 bool functionbody = scope->function_body;
682 bool keep = functionbody || scope->keep || scope->bindings;
684 c_end_vm_scope (scope->depth);
686 /* If appropriate, create a BLOCK to record the decls for the life
687 of this function. */
688 block = 0;
689 if (keep)
691 block = make_node (BLOCK);
692 BLOCK_SUBBLOCKS (block) = scope->blocks;
693 TREE_USED (block) = 1;
695 /* In each subblock, record that this is its superior. */
696 for (p = scope->blocks; p; p = TREE_CHAIN (p))
697 BLOCK_SUPERCONTEXT (p) = block;
699 BLOCK_VARS (block) = 0;
702 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
703 scope must be set so that they point to the appropriate
704 construct, i.e. either to the current FUNCTION_DECL node, or
705 else to the BLOCK node we just constructed.
707 Note that for tagged types whose scope is just the formal
708 parameter list for some function type specification, we can't
709 properly set their TYPE_CONTEXTs here, because we don't have a
710 pointer to the appropriate FUNCTION_TYPE node readily available
711 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
712 type nodes get set in `grokdeclarator' as soon as we have created
713 the FUNCTION_TYPE node which will represent the "scope" for these
714 "parameter list local" tagged types. */
715 if (scope->function_body)
716 context = current_function_decl;
717 else if (scope == file_scope)
719 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
720 TREE_CHAIN (file_decl) = all_translation_units;
721 all_translation_units = file_decl;
722 context = file_decl;
724 else
725 context = block;
727 /* Clear all bindings in this scope. */
728 for (b = scope->bindings; b; b = free_binding_and_advance (b))
730 p = b->decl;
731 switch (TREE_CODE (p))
733 case LABEL_DECL:
734 /* Warnings for unused labels, errors for undefined labels. */
735 if (TREE_USED (p) && !DECL_INITIAL (p))
737 error ("label %q+D used but not defined", p);
738 DECL_INITIAL (p) = error_mark_node;
740 else
741 warn_for_unused_label (p);
743 /* Labels go in BLOCK_VARS. */
744 TREE_CHAIN (p) = BLOCK_VARS (block);
745 BLOCK_VARS (block) = p;
746 gcc_assert (I_LABEL_BINDING (b->id) == b);
747 I_LABEL_BINDING (b->id) = b->shadowed;
748 break;
750 case ENUMERAL_TYPE:
751 case UNION_TYPE:
752 case RECORD_TYPE:
753 set_type_context (p, context);
755 /* Types may not have tag-names, in which case the type
756 appears in the bindings list with b->id NULL. */
757 if (b->id)
759 gcc_assert (I_TAG_BINDING (b->id) == b);
760 I_TAG_BINDING (b->id) = b->shadowed;
762 break;
764 case FUNCTION_DECL:
765 /* Propagate TREE_ADDRESSABLE from nested functions to their
766 containing functions. */
767 if (!TREE_ASM_WRITTEN (p)
768 && DECL_INITIAL (p) != 0
769 && TREE_ADDRESSABLE (p)
770 && DECL_ABSTRACT_ORIGIN (p) != 0
771 && DECL_ABSTRACT_ORIGIN (p) != p)
772 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
773 if (!DECL_EXTERNAL (p)
774 && !DECL_INITIAL (p)
775 && scope != file_scope
776 && scope != external_scope)
778 error ("nested function %q+D declared but never defined", p);
779 undef_nested_function = true;
781 /* C99 6.7.4p6: "a function with external linkage... declared
782 with an inline function specifier ... shall also be defined in the
783 same translation unit." */
784 else if (DECL_DECLARED_INLINE_P (p)
785 && TREE_PUBLIC (p)
786 && !DECL_INITIAL (p)
787 && !flag_gnu89_inline)
788 pedwarn ("inline function %q+D declared but never defined", p);
790 goto common_symbol;
792 case VAR_DECL:
793 /* Warnings for unused variables. */
794 if (!TREE_USED (p)
795 && !TREE_NO_WARNING (p)
796 && !DECL_IN_SYSTEM_HEADER (p)
797 && DECL_NAME (p)
798 && !DECL_ARTIFICIAL (p)
799 && scope != file_scope
800 && scope != external_scope)
801 warning (OPT_Wunused_variable, "unused variable %q+D", p);
803 if (b->inner_comp)
805 error ("type of array %q+D completed incompatibly with"
806 " implicit initialization", p);
809 /* Fall through. */
810 case TYPE_DECL:
811 case CONST_DECL:
812 common_symbol:
813 /* All of these go in BLOCK_VARS, but only if this is the
814 binding in the home scope. */
815 if (!b->nested)
817 TREE_CHAIN (p) = BLOCK_VARS (block);
818 BLOCK_VARS (block) = p;
820 /* If this is the file scope, and we are processing more
821 than one translation unit in this compilation, set
822 DECL_CONTEXT of each decl to the TRANSLATION_UNIT_DECL.
823 This makes same_translation_unit_p work, and causes
824 static declarations to be given disambiguating suffixes. */
825 if (scope == file_scope && num_in_fnames > 1)
827 DECL_CONTEXT (p) = context;
828 if (TREE_CODE (p) == TYPE_DECL)
829 set_type_context (TREE_TYPE (p), context);
832 /* Fall through. */
833 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
834 already been put there by store_parm_decls. Unused-
835 parameter warnings are handled by function.c.
836 error_mark_node obviously does not go in BLOCK_VARS and
837 does not get unused-variable warnings. */
838 case PARM_DECL:
839 case ERROR_MARK:
840 /* It is possible for a decl not to have a name. We get
841 here with b->id NULL in this case. */
842 if (b->id)
844 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
845 I_SYMBOL_BINDING (b->id) = b->shadowed;
846 if (b->shadowed && b->shadowed->type)
847 TREE_TYPE (b->shadowed->decl) = b->shadowed->type;
849 break;
851 default:
852 gcc_unreachable ();
857 /* Dispose of the block that we just made inside some higher level. */
858 if ((scope->function_body || scope == file_scope) && context)
860 DECL_INITIAL (context) = block;
861 BLOCK_SUPERCONTEXT (block) = context;
863 else if (scope->outer)
865 if (block)
866 SCOPE_LIST_APPEND (scope->outer, blocks, block);
867 /* If we did not make a block for the scope just exited, any
868 blocks made for inner scopes must be carried forward so they
869 will later become subblocks of something else. */
870 else if (scope->blocks)
871 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
874 /* Pop the current scope, and free the structure for reuse. */
875 current_scope = scope->outer;
876 if (scope->function_body)
877 current_function_scope = scope->outer_function;
879 memset (scope, 0, sizeof (struct c_scope));
880 scope->outer = scope_freelist;
881 scope_freelist = scope;
883 return block;
886 void
887 push_file_scope (void)
889 tree decl;
891 if (file_scope)
892 return;
894 push_scope ();
895 file_scope = current_scope;
897 start_fname_decls ();
899 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
900 bind (DECL_NAME (decl), decl, file_scope,
901 /*invisible=*/false, /*nested=*/true);
904 void
905 pop_file_scope (void)
907 /* In case there were missing closebraces, get us back to the global
908 binding level. */
909 while (current_scope != file_scope)
910 pop_scope ();
912 /* __FUNCTION__ is defined at file scope (""). This
913 call may not be necessary as my tests indicate it
914 still works without it. */
915 finish_fname_decls ();
917 /* This is the point to write out a PCH if we're doing that.
918 In that case we do not want to do anything else. */
919 if (pch_file)
921 c_common_write_pch ();
922 return;
925 /* Pop off the file scope and close this translation unit. */
926 pop_scope ();
927 file_scope = 0;
929 maybe_apply_pending_pragma_weaks ();
930 cgraph_finalize_compilation_unit ();
933 /* Insert BLOCK at the end of the list of subblocks of the current
934 scope. This is used when a BIND_EXPR is expanded, to handle the
935 BLOCK node inside the BIND_EXPR. */
937 void
938 insert_block (tree block)
940 TREE_USED (block) = 1;
941 SCOPE_LIST_APPEND (current_scope, blocks, block);
944 /* Push a definition or a declaration of struct, union or enum tag "name".
945 "type" should be the type node.
946 We assume that the tag "name" is not already defined.
948 Note that the definition may really be just a forward reference.
949 In that case, the TYPE_SIZE will be zero. */
951 static void
952 pushtag (tree name, tree type)
954 /* Record the identifier as the type's name if it has none. */
955 if (name && !TYPE_NAME (type))
956 TYPE_NAME (type) = name;
957 bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
959 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
960 tagged type we just added to the current scope. This fake
961 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
962 to output a representation of a tagged type, and it also gives
963 us a convenient place to record the "scope start" address for the
964 tagged type. */
966 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
968 /* An approximation for now, so we can tell this is a function-scope tag.
969 This will be updated in pop_scope. */
970 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
973 /* Subroutine of compare_decls. Allow harmless mismatches in return
974 and argument types provided that the type modes match. This function
975 return a unified type given a suitable match, and 0 otherwise. */
977 static tree
978 match_builtin_function_types (tree newtype, tree oldtype)
980 tree newrettype, oldrettype;
981 tree newargs, oldargs;
982 tree trytype, tryargs;
984 /* Accept the return type of the new declaration if same modes. */
985 oldrettype = TREE_TYPE (oldtype);
986 newrettype = TREE_TYPE (newtype);
988 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
989 return 0;
991 oldargs = TYPE_ARG_TYPES (oldtype);
992 newargs = TYPE_ARG_TYPES (newtype);
993 tryargs = newargs;
995 while (oldargs || newargs)
997 if (!oldargs
998 || !newargs
999 || !TREE_VALUE (oldargs)
1000 || !TREE_VALUE (newargs)
1001 || TYPE_MODE (TREE_VALUE (oldargs))
1002 != TYPE_MODE (TREE_VALUE (newargs)))
1003 return 0;
1005 oldargs = TREE_CHAIN (oldargs);
1006 newargs = TREE_CHAIN (newargs);
1009 trytype = build_function_type (newrettype, tryargs);
1010 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
1013 /* Subroutine of diagnose_mismatched_decls. Check for function type
1014 mismatch involving an empty arglist vs a nonempty one and give clearer
1015 diagnostics. */
1016 static void
1017 diagnose_arglist_conflict (tree newdecl, tree olddecl,
1018 tree newtype, tree oldtype)
1020 tree t;
1022 if (TREE_CODE (olddecl) != FUNCTION_DECL
1023 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
1024 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
1026 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
1027 return;
1029 t = TYPE_ARG_TYPES (oldtype);
1030 if (t == 0)
1031 t = TYPE_ARG_TYPES (newtype);
1032 for (; t; t = TREE_CHAIN (t))
1034 tree type = TREE_VALUE (t);
1036 if (TREE_CHAIN (t) == 0
1037 && TYPE_MAIN_VARIANT (type) != void_type_node)
1039 inform ("a parameter list with an ellipsis can%'t match "
1040 "an empty parameter name list declaration");
1041 break;
1044 if (c_type_promotes_to (type) != type)
1046 inform ("an argument type that has a default promotion can%'t match "
1047 "an empty parameter name list declaration");
1048 break;
1053 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
1054 old-style function definition, NEWDECL is a prototype declaration.
1055 Diagnose inconsistencies in the argument list. Returns TRUE if
1056 the prototype is compatible, FALSE if not. */
1057 static bool
1058 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
1060 tree newargs, oldargs;
1061 int i;
1063 #define END_OF_ARGLIST(t) ((t) == void_type_node)
1065 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
1066 newargs = TYPE_ARG_TYPES (newtype);
1067 i = 1;
1069 for (;;)
1071 tree oldargtype = TREE_VALUE (oldargs);
1072 tree newargtype = TREE_VALUE (newargs);
1074 if (oldargtype == error_mark_node || newargtype == error_mark_node)
1075 return false;
1077 oldargtype = TYPE_MAIN_VARIANT (oldargtype);
1078 newargtype = TYPE_MAIN_VARIANT (newargtype);
1080 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
1081 break;
1083 /* Reaching the end of just one list means the two decls don't
1084 agree on the number of arguments. */
1085 if (END_OF_ARGLIST (oldargtype))
1087 error ("prototype for %q+D declares more arguments "
1088 "than previous old-style definition", newdecl);
1089 return false;
1091 else if (END_OF_ARGLIST (newargtype))
1093 error ("prototype for %q+D declares fewer arguments "
1094 "than previous old-style definition", newdecl);
1095 return false;
1098 /* Type for passing arg must be consistent with that declared
1099 for the arg. */
1100 else if (!comptypes (oldargtype, newargtype))
1102 error ("prototype for %q+D declares argument %d"
1103 " with incompatible type",
1104 newdecl, i);
1105 return false;
1108 oldargs = TREE_CHAIN (oldargs);
1109 newargs = TREE_CHAIN (newargs);
1110 i++;
1113 /* If we get here, no errors were found, but do issue a warning
1114 for this poor-style construct. */
1115 warning (0, "prototype for %q+D follows non-prototype definition",
1116 newdecl);
1117 return true;
1118 #undef END_OF_ARGLIST
1121 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1122 first in a pair of mismatched declarations, using the diagnostic
1123 function DIAG. */
1124 static void
1125 locate_old_decl (tree decl, void (*diag)(const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2))
1127 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1129 else if (DECL_INITIAL (decl))
1130 diag (G_("previous definition of %q+D was here"), decl);
1131 else if (C_DECL_IMPLICIT (decl))
1132 diag (G_("previous implicit declaration of %q+D was here"), decl);
1133 else
1134 diag (G_("previous declaration of %q+D was here"), decl);
1137 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1138 Returns true if the caller should proceed to merge the two, false
1139 if OLDDECL should simply be discarded. As a side effect, issues
1140 all necessary diagnostics for invalid or poor-style combinations.
1141 If it returns true, writes the types of NEWDECL and OLDDECL to
1142 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1143 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1145 static bool
1146 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1147 tree *newtypep, tree *oldtypep)
1149 tree newtype, oldtype;
1150 bool pedwarned = false;
1151 bool warned = false;
1152 bool retval = true;
1154 #define DECL_EXTERN_INLINE(DECL) (DECL_DECLARED_INLINE_P (DECL) \
1155 && DECL_EXTERNAL (DECL))
1157 /* If we have error_mark_node for either decl or type, just discard
1158 the previous decl - we're in an error cascade already. */
1159 if (olddecl == error_mark_node || newdecl == error_mark_node)
1160 return false;
1161 *oldtypep = oldtype = TREE_TYPE (olddecl);
1162 *newtypep = newtype = TREE_TYPE (newdecl);
1163 if (oldtype == error_mark_node || newtype == error_mark_node)
1164 return false;
1166 /* Two different categories of symbol altogether. This is an error
1167 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1168 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1170 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1171 && DECL_BUILT_IN (olddecl)
1172 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1174 error ("%q+D redeclared as different kind of symbol", newdecl);
1175 locate_old_decl (olddecl, error);
1177 else if (TREE_PUBLIC (newdecl))
1178 warning (0, "built-in function %q+D declared as non-function",
1179 newdecl);
1180 else
1181 warning (OPT_Wshadow, "declaration of %q+D shadows "
1182 "a built-in function", newdecl);
1183 return false;
1186 /* Enumerators have no linkage, so may only be declared once in a
1187 given scope. */
1188 if (TREE_CODE (olddecl) == CONST_DECL)
1190 error ("redeclaration of enumerator %q+D", newdecl);
1191 locate_old_decl (olddecl, error);
1192 return false;
1195 if (!comptypes (oldtype, newtype))
1197 if (TREE_CODE (olddecl) == FUNCTION_DECL
1198 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1200 /* Accept harmless mismatch in function types.
1201 This is for the ffs and fprintf builtins. */
1202 tree trytype = match_builtin_function_types (newtype, oldtype);
1204 if (trytype && comptypes (newtype, trytype))
1205 *oldtypep = oldtype = trytype;
1206 else
1208 /* If types don't match for a built-in, throw away the
1209 built-in. No point in calling locate_old_decl here, it
1210 won't print anything. */
1211 warning (0, "conflicting types for built-in function %q+D",
1212 newdecl);
1213 return false;
1216 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1217 && DECL_IS_BUILTIN (olddecl))
1219 /* A conflicting function declaration for a predeclared
1220 function that isn't actually built in. Objective C uses
1221 these. The new declaration silently overrides everything
1222 but the volatility (i.e. noreturn) indication. See also
1223 below. FIXME: Make Objective C use normal builtins. */
1224 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1225 return false;
1227 /* Permit void foo (...) to match int foo (...) if the latter is
1228 the definition and implicit int was used. See
1229 c-torture/compile/920625-2.c. */
1230 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1231 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1232 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1233 && C_FUNCTION_IMPLICIT_INT (newdecl) && !DECL_INITIAL (olddecl))
1235 pedwarn ("conflicting types for %q+D", newdecl);
1236 /* Make sure we keep void as the return type. */
1237 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1238 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1239 pedwarned = true;
1241 /* Permit void foo (...) to match an earlier call to foo (...) with
1242 no declared type (thus, implicitly int). */
1243 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1244 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == void_type_node
1245 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == integer_type_node
1246 && C_DECL_IMPLICIT (olddecl) && !DECL_INITIAL (olddecl))
1248 pedwarn ("conflicting types for %q+D", newdecl);
1249 /* Make sure we keep void as the return type. */
1250 TREE_TYPE (olddecl) = *oldtypep = oldtype = newtype;
1251 pedwarned = true;
1253 else
1255 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1256 error ("conflicting type qualifiers for %q+D", newdecl);
1257 else
1258 error ("conflicting types for %q+D", newdecl);
1259 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1260 locate_old_decl (olddecl, error);
1261 return false;
1265 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1266 but silently ignore the redeclaration if either is in a system
1267 header. (Conflicting redeclarations were handled above.) */
1268 if (TREE_CODE (newdecl) == TYPE_DECL)
1270 if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
1271 return true; /* Allow OLDDECL to continue in use. */
1273 error ("redefinition of typedef %q+D", newdecl);
1274 locate_old_decl (olddecl, error);
1275 return false;
1278 /* Function declarations can either be 'static' or 'extern' (no
1279 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1280 can never conflict with each other on account of linkage
1281 (6.2.2p4). Multiple definitions are not allowed (6.9p3,5) but
1282 gnu89 mode permits two definitions if one is 'extern inline' and
1283 one is not. The non- extern-inline definition supersedes the
1284 extern-inline definition. */
1286 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1288 /* If you declare a built-in function name as static, or
1289 define the built-in with an old-style definition (so we
1290 can't validate the argument list) the built-in definition is
1291 overridden, but optionally warn this was a bad choice of name. */
1292 if (DECL_BUILT_IN (olddecl)
1293 && !C_DECL_DECLARED_BUILTIN (olddecl)
1294 && (!TREE_PUBLIC (newdecl)
1295 || (DECL_INITIAL (newdecl)
1296 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1298 warning (OPT_Wshadow, "declaration of %q+D shadows "
1299 "a built-in function", newdecl);
1300 /* Discard the old built-in function. */
1301 return false;
1304 if (DECL_INITIAL (newdecl))
1306 if (DECL_INITIAL (olddecl))
1308 /* If both decls are in the same TU and the new declaration
1309 isn't overriding an extern inline reject the new decl.
1310 In c99, no overriding is allowed in the same translation
1311 unit. */
1312 if ((!DECL_EXTERN_INLINE (olddecl)
1313 || DECL_EXTERN_INLINE (newdecl)
1314 || (!flag_gnu89_inline
1315 && (!DECL_DECLARED_INLINE_P (olddecl)
1316 || !lookup_attribute ("gnu_inline",
1317 DECL_ATTRIBUTES (olddecl)))
1318 && (!DECL_DECLARED_INLINE_P (newdecl)
1319 || !lookup_attribute ("gnu_inline",
1320 DECL_ATTRIBUTES (newdecl))))
1322 && same_translation_unit_p (newdecl, olddecl))
1324 error ("redefinition of %q+D", newdecl);
1325 locate_old_decl (olddecl, error);
1326 return false;
1330 /* If we have a prototype after an old-style function definition,
1331 the argument types must be checked specially. */
1332 else if (DECL_INITIAL (olddecl)
1333 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1334 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1335 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1337 locate_old_decl (olddecl, error);
1338 return false;
1340 /* A non-static declaration (even an "extern") followed by a
1341 static declaration is undefined behavior per C99 6.2.2p3-5,7.
1342 The same is true for a static forward declaration at block
1343 scope followed by a non-static declaration/definition at file
1344 scope. Static followed by non-static at the same scope is
1345 not undefined behavior, and is the most convenient way to get
1346 some effects (see e.g. what unwind-dw2-fde-glibc.c does to
1347 the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
1348 we do diagnose it if -Wtraditional. */
1349 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1351 /* Two exceptions to the rule. If olddecl is an extern
1352 inline, or a predeclared function that isn't actually
1353 built in, newdecl silently overrides olddecl. The latter
1354 occur only in Objective C; see also above. (FIXME: Make
1355 Objective C use normal builtins.) */
1356 if (!DECL_IS_BUILTIN (olddecl)
1357 && !DECL_EXTERN_INLINE (olddecl))
1359 error ("static declaration of %q+D follows "
1360 "non-static declaration", newdecl);
1361 locate_old_decl (olddecl, error);
1363 return false;
1365 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
1367 if (DECL_CONTEXT (olddecl))
1369 error ("non-static declaration of %q+D follows "
1370 "static declaration", newdecl);
1371 locate_old_decl (olddecl, error);
1372 return false;
1374 else if (warn_traditional)
1376 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1377 "follows static declaration", newdecl);
1378 warned = true;
1382 /* Make sure gnu_inline attribute is either not present, or
1383 present on all inline decls. */
1384 if (DECL_DECLARED_INLINE_P (olddecl)
1385 && DECL_DECLARED_INLINE_P (newdecl))
1387 bool newa = lookup_attribute ("gnu_inline",
1388 DECL_ATTRIBUTES (newdecl)) != NULL;
1389 bool olda = lookup_attribute ("gnu_inline",
1390 DECL_ATTRIBUTES (olddecl)) != NULL;
1391 if (newa != olda)
1393 error ("%<gnu_inline%> attribute present on %q+D",
1394 newa ? newdecl : olddecl);
1395 error ("%Jbut not here", newa ? olddecl : newdecl);
1399 else if (TREE_CODE (newdecl) == VAR_DECL)
1401 /* Only variables can be thread-local, and all declarations must
1402 agree on this property. */
1403 if (C_DECL_THREADPRIVATE_P (olddecl) && !DECL_THREAD_LOCAL_P (newdecl))
1405 /* Nothing to check. Since OLDDECL is marked threadprivate
1406 and NEWDECL does not have a thread-local attribute, we
1407 will merge the threadprivate attribute into NEWDECL. */
1410 else if (DECL_THREAD_LOCAL_P (newdecl) != DECL_THREAD_LOCAL_P (olddecl))
1412 if (DECL_THREAD_LOCAL_P (newdecl))
1413 error ("thread-local declaration of %q+D follows "
1414 "non-thread-local declaration", newdecl);
1415 else
1416 error ("non-thread-local declaration of %q+D follows "
1417 "thread-local declaration", newdecl);
1419 locate_old_decl (olddecl, error);
1420 return false;
1423 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1424 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1426 error ("redefinition of %q+D", newdecl);
1427 locate_old_decl (olddecl, error);
1428 return false;
1431 /* Objects declared at file scope: if the first declaration had
1432 external linkage (even if it was an external reference) the
1433 second must have external linkage as well, or the behavior is
1434 undefined. If the first declaration had internal linkage, then
1435 the second must too, or else be an external reference (in which
1436 case the composite declaration still has internal linkage).
1437 As for function declarations, we warn about the static-then-
1438 extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
1439 if (DECL_FILE_SCOPE_P (newdecl)
1440 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1442 if (DECL_EXTERNAL (newdecl))
1444 if (!DECL_FILE_SCOPE_P (olddecl))
1446 error ("extern declaration of %q+D follows "
1447 "declaration with no linkage", newdecl);
1448 locate_old_decl (olddecl, error);
1449 return false;
1451 else if (warn_traditional)
1453 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1454 "follows static declaration", newdecl);
1455 warned = true;
1458 else
1460 if (TREE_PUBLIC (newdecl))
1461 error ("non-static declaration of %q+D follows "
1462 "static declaration", newdecl);
1463 else
1464 error ("static declaration of %q+D follows "
1465 "non-static declaration", newdecl);
1467 locate_old_decl (olddecl, error);
1468 return false;
1471 /* Two objects with the same name declared at the same block
1472 scope must both be external references (6.7p3). */
1473 else if (!DECL_FILE_SCOPE_P (newdecl))
1475 if (DECL_EXTERNAL (newdecl))
1477 /* Extern with initializer at block scope, which will
1478 already have received an error. */
1480 else if (DECL_EXTERNAL (olddecl))
1482 error ("declaration of %q+D with no linkage follows "
1483 "extern declaration", newdecl);
1484 locate_old_decl (olddecl, error);
1486 else
1488 error ("redeclaration of %q+D with no linkage", newdecl);
1489 locate_old_decl (olddecl, error);
1492 return false;
1496 /* warnings */
1497 /* All decls must agree on a visibility. */
1498 if (CODE_CONTAINS_STRUCT (TREE_CODE (newdecl), TS_DECL_WITH_VIS)
1499 && DECL_VISIBILITY_SPECIFIED (newdecl) && DECL_VISIBILITY_SPECIFIED (olddecl)
1500 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1502 warning (0, "redeclaration of %q+D with different visibility "
1503 "(old visibility preserved)", newdecl);
1504 warned = true;
1507 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1509 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1510 if (DECL_DECLARED_INLINE_P (newdecl)
1511 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1513 warning (OPT_Wattributes, "inline declaration of %qD follows "
1514 "declaration with attribute noinline", newdecl);
1515 warned = true;
1517 else if (DECL_DECLARED_INLINE_P (olddecl)
1518 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1520 warning (OPT_Wattributes, "declaration of %q+D with attribute "
1521 "noinline follows inline declaration ", newdecl);
1522 warned = true;
1525 /* Inline declaration after use or definition.
1526 ??? Should we still warn about this now we have unit-at-a-time
1527 mode and can get it right?
1528 Definitely don't complain if the decls are in different translation
1529 units.
1530 C99 permits this, so don't warn in that case. (The function
1531 may not be inlined everywhere in function-at-a-time mode, but
1532 we still shouldn't warn.) */
1533 if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl)
1534 && same_translation_unit_p (olddecl, newdecl)
1535 && flag_gnu89_inline)
1537 if (TREE_USED (olddecl))
1539 warning (0, "%q+D declared inline after being called", olddecl);
1540 warned = true;
1542 else if (DECL_INITIAL (olddecl))
1544 warning (0, "%q+D declared inline after its definition", olddecl);
1545 warned = true;
1549 else /* PARM_DECL, VAR_DECL */
1551 /* Redeclaration of a parameter is a constraint violation (this is
1552 not explicitly stated, but follows from C99 6.7p3 [no more than
1553 one declaration of the same identifier with no linkage in the
1554 same scope, except type tags] and 6.2.2p6 [parameters have no
1555 linkage]). We must check for a forward parameter declaration,
1556 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1557 an extension, the mandatory diagnostic for which is handled by
1558 mark_forward_parm_decls. */
1560 if (TREE_CODE (newdecl) == PARM_DECL
1561 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1563 error ("redefinition of parameter %q+D", newdecl);
1564 locate_old_decl (olddecl, error);
1565 return false;
1569 /* Optional warning for completely redundant decls. */
1570 if (!warned && !pedwarned
1571 && warn_redundant_decls
1572 /* Don't warn about a function declaration followed by a
1573 definition. */
1574 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1575 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1576 /* Don't warn about redundant redeclarations of builtins. */
1577 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1578 && !DECL_BUILT_IN (newdecl)
1579 && DECL_BUILT_IN (olddecl)
1580 && !C_DECL_DECLARED_BUILTIN (olddecl))
1581 /* Don't warn about an extern followed by a definition. */
1582 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1583 /* Don't warn about forward parameter decls. */
1584 && !(TREE_CODE (newdecl) == PARM_DECL
1585 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1586 /* Don't warn about a variable definition following a declaration. */
1587 && !(TREE_CODE (newdecl) == VAR_DECL
1588 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl)))
1590 warning (OPT_Wredundant_decls, "redundant redeclaration of %q+D",
1591 newdecl);
1592 warned = true;
1595 /* Report location of previous decl/defn in a consistent manner. */
1596 if (warned || pedwarned)
1597 locate_old_decl (olddecl, pedwarned ? pedwarn : warning0);
1599 #undef DECL_EXTERN_INLINE
1601 return retval;
1604 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1605 consistent with OLDDECL, but carries new information. Merge the
1606 new information into OLDDECL. This function issues no
1607 diagnostics. */
1609 static void
1610 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1612 bool new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1613 && DECL_INITIAL (newdecl) != 0);
1614 bool new_is_prototype = (TREE_CODE (newdecl) == FUNCTION_DECL
1615 && TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0);
1616 bool old_is_prototype = (TREE_CODE (olddecl) == FUNCTION_DECL
1617 && TYPE_ARG_TYPES (TREE_TYPE (olddecl)) != 0);
1618 bool extern_changed = false;
1620 /* For real parm decl following a forward decl, rechain the old decl
1621 in its new location and clear TREE_ASM_WRITTEN (it's not a
1622 forward decl anymore). */
1623 if (TREE_CODE (newdecl) == PARM_DECL
1624 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1626 struct c_binding *b, **here;
1628 for (here = &current_scope->bindings; *here; here = &(*here)->prev)
1629 if ((*here)->decl == olddecl)
1630 goto found;
1631 gcc_unreachable ();
1633 found:
1634 b = *here;
1635 *here = b->prev;
1636 b->prev = current_scope->bindings;
1637 current_scope->bindings = b;
1639 TREE_ASM_WRITTEN (olddecl) = 0;
1642 DECL_ATTRIBUTES (newdecl)
1643 = targetm.merge_decl_attributes (olddecl, newdecl);
1645 /* Merge the data types specified in the two decls. */
1646 TREE_TYPE (newdecl)
1647 = TREE_TYPE (olddecl)
1648 = composite_type (newtype, oldtype);
1650 /* Lay the type out, unless already done. */
1651 if (!comptypes (oldtype, TREE_TYPE (newdecl)))
1653 if (TREE_TYPE (newdecl) != error_mark_node)
1654 layout_type (TREE_TYPE (newdecl));
1655 if (TREE_CODE (newdecl) != FUNCTION_DECL
1656 && TREE_CODE (newdecl) != TYPE_DECL
1657 && TREE_CODE (newdecl) != CONST_DECL)
1658 layout_decl (newdecl, 0);
1660 else
1662 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1663 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1664 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1665 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1666 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1668 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1669 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1674 /* Merge the type qualifiers. */
1675 if (TREE_READONLY (newdecl))
1676 TREE_READONLY (olddecl) = 1;
1678 if (TREE_THIS_VOLATILE (newdecl))
1679 TREE_THIS_VOLATILE (olddecl) = 1;
1681 /* Merge deprecatedness. */
1682 if (TREE_DEPRECATED (newdecl))
1683 TREE_DEPRECATED (olddecl) = 1;
1685 /* Keep source location of definition rather than declaration and of
1686 prototype rather than non-prototype unless that prototype is
1687 built-in. */
1688 if ((DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1689 || (old_is_prototype && !new_is_prototype
1690 && !C_DECL_BUILTIN_PROTOTYPE (olddecl)))
1691 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1693 /* Merge the initialization information. */
1694 if (DECL_INITIAL (newdecl) == 0)
1695 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1697 /* Merge the threadprivate attribute. */
1698 if (TREE_CODE (olddecl) == VAR_DECL && C_DECL_THREADPRIVATE_P (olddecl))
1700 DECL_TLS_MODEL (newdecl) = DECL_TLS_MODEL (olddecl);
1701 C_DECL_THREADPRIVATE_P (newdecl) = 1;
1704 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS))
1706 /* Merge the unused-warning information. */
1707 if (DECL_IN_SYSTEM_HEADER (olddecl))
1708 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1709 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1710 DECL_IN_SYSTEM_HEADER (olddecl) = 1;
1712 /* Merge the section attribute.
1713 We want to issue an error if the sections conflict but that
1714 must be done later in decl_attributes since we are called
1715 before attributes are assigned. */
1716 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1717 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1719 /* Copy the assembler name.
1720 Currently, it can only be defined in the prototype. */
1721 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1723 /* Use visibility of whichever declaration had it specified */
1724 if (DECL_VISIBILITY_SPECIFIED (olddecl))
1726 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1727 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
1730 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1732 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1733 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1734 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1735 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1736 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1737 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1738 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1739 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1740 DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
1741 DECL_IS_NOVOPS (newdecl) |= DECL_IS_NOVOPS (olddecl);
1744 /* Merge the storage class information. */
1745 merge_weak (newdecl, olddecl);
1747 /* For functions, static overrides non-static. */
1748 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1750 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1751 /* This is since we don't automatically
1752 copy the attributes of NEWDECL into OLDDECL. */
1753 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1754 /* If this clears `static', clear it in the identifier too. */
1755 if (!TREE_PUBLIC (olddecl))
1756 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1760 /* In c99, 'extern' declaration before (or after) 'inline' means this
1761 function is not DECL_EXTERNAL, unless 'gnu_inline' attribute
1762 is present. */
1763 if (TREE_CODE (newdecl) == FUNCTION_DECL
1764 && !flag_gnu89_inline
1765 && (DECL_DECLARED_INLINE_P (newdecl)
1766 || DECL_DECLARED_INLINE_P (olddecl))
1767 && (!DECL_DECLARED_INLINE_P (newdecl)
1768 || !DECL_DECLARED_INLINE_P (olddecl)
1769 || !DECL_EXTERNAL (olddecl))
1770 && DECL_EXTERNAL (newdecl)
1771 && !lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (newdecl)))
1772 DECL_EXTERNAL (newdecl) = 0;
1774 if (DECL_EXTERNAL (newdecl))
1776 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1777 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1779 /* An extern decl does not override previous storage class. */
1780 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1781 if (!DECL_EXTERNAL (newdecl))
1783 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1784 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1787 else
1789 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1790 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1793 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1795 /* If we're redefining a function previously defined as extern
1796 inline, make sure we emit debug info for the inline before we
1797 throw it away, in case it was inlined into a function that
1798 hasn't been written out yet. */
1799 if (new_is_definition && DECL_INITIAL (olddecl))
1801 if (TREE_USED (olddecl)
1802 /* In unit-at-a-time mode we never inline re-defined extern
1803 inline functions. */
1804 && !flag_unit_at_a_time
1805 && cgraph_function_possibly_inlined_p (olddecl))
1806 (*debug_hooks->outlining_inline_function) (olddecl);
1808 /* The new defn must not be inline. */
1809 DECL_INLINE (newdecl) = 0;
1810 DECL_UNINLINABLE (newdecl) = 1;
1812 else
1814 /* If either decl says `inline', this fn is inline, unless
1815 its definition was passed already. */
1816 if (DECL_DECLARED_INLINE_P (newdecl)
1817 || DECL_DECLARED_INLINE_P (olddecl))
1818 DECL_DECLARED_INLINE_P (newdecl) = 1;
1820 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1821 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1823 DECL_DISREGARD_INLINE_LIMITS (newdecl)
1824 = DECL_DISREGARD_INLINE_LIMITS (olddecl)
1825 = (DECL_DISREGARD_INLINE_LIMITS (newdecl)
1826 || DECL_DISREGARD_INLINE_LIMITS (olddecl));
1829 if (DECL_BUILT_IN (olddecl))
1831 /* If redeclaring a builtin function, it stays built in.
1832 But it gets tagged as having been declared. */
1833 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1834 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1835 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1836 if (new_is_prototype)
1837 C_DECL_BUILTIN_PROTOTYPE (newdecl) = 0;
1838 else
1839 C_DECL_BUILTIN_PROTOTYPE (newdecl)
1840 = C_DECL_BUILTIN_PROTOTYPE (olddecl);
1843 /* Also preserve various other info from the definition. */
1844 if (!new_is_definition)
1846 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1847 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1848 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1849 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1850 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1852 /* Set DECL_INLINE on the declaration if we've got a body
1853 from which to instantiate. */
1854 if (DECL_INLINE (olddecl) && !DECL_UNINLINABLE (newdecl))
1856 DECL_INLINE (newdecl) = 1;
1857 DECL_ABSTRACT_ORIGIN (newdecl)
1858 = DECL_ABSTRACT_ORIGIN (olddecl);
1861 else
1863 /* If a previous declaration said inline, mark the
1864 definition as inlinable. */
1865 if (DECL_DECLARED_INLINE_P (newdecl)
1866 && !DECL_UNINLINABLE (newdecl))
1867 DECL_INLINE (newdecl) = 1;
1871 extern_changed = DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl);
1873 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1874 But preserve OLDDECL's DECL_UID and DECL_CONTEXT. */
1876 unsigned olddecl_uid = DECL_UID (olddecl);
1877 tree olddecl_context = DECL_CONTEXT (olddecl);
1879 memcpy ((char *) olddecl + sizeof (struct tree_common),
1880 (char *) newdecl + sizeof (struct tree_common),
1881 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
1882 switch (TREE_CODE (olddecl))
1884 case FIELD_DECL:
1885 case VAR_DECL:
1886 case PARM_DECL:
1887 case LABEL_DECL:
1888 case RESULT_DECL:
1889 case CONST_DECL:
1890 case TYPE_DECL:
1891 case FUNCTION_DECL:
1892 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1893 (char *) newdecl + sizeof (struct tree_decl_common),
1894 tree_code_size (TREE_CODE (olddecl)) - sizeof (struct tree_decl_common));
1895 break;
1897 default:
1899 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1900 (char *) newdecl + sizeof (struct tree_decl_common),
1901 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common));
1903 DECL_UID (olddecl) = olddecl_uid;
1904 DECL_CONTEXT (olddecl) = olddecl_context;
1907 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1908 so that encode_section_info has a chance to look at the new decl
1909 flags and attributes. */
1910 if (DECL_RTL_SET_P (olddecl)
1911 && (TREE_CODE (olddecl) == FUNCTION_DECL
1912 || (TREE_CODE (olddecl) == VAR_DECL
1913 && TREE_STATIC (olddecl))))
1914 make_decl_rtl (olddecl);
1916 /* If we changed a function from DECL_EXTERNAL to !DECL_EXTERNAL,
1917 and the definition is coming from the old version, cgraph needs
1918 to be called again. */
1919 if (extern_changed && !new_is_definition
1920 && TREE_CODE (olddecl) == FUNCTION_DECL && DECL_INITIAL (olddecl))
1921 cgraph_finalize_function (olddecl, false);
1924 /* Handle when a new declaration NEWDECL has the same name as an old
1925 one OLDDECL in the same binding contour. Prints an error message
1926 if appropriate.
1928 If safely possible, alter OLDDECL to look like NEWDECL, and return
1929 true. Otherwise, return false. */
1931 static bool
1932 duplicate_decls (tree newdecl, tree olddecl)
1934 tree newtype = NULL, oldtype = NULL;
1936 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1938 /* Avoid `unused variable' and other warnings for OLDDECL. */
1939 TREE_NO_WARNING (olddecl) = 1;
1940 return false;
1943 merge_decls (newdecl, olddecl, newtype, oldtype);
1944 return true;
1948 /* Check whether decl-node NEW_DECL shadows an existing declaration. */
1949 static void
1950 warn_if_shadowing (tree new_decl)
1952 struct c_binding *b;
1954 /* Shadow warnings wanted? */
1955 if (!warn_shadow
1956 /* No shadow warnings for internally generated vars. */
1957 || DECL_IS_BUILTIN (new_decl)
1958 /* No shadow warnings for vars made for inlining. */
1959 || DECL_FROM_INLINE (new_decl))
1960 return;
1962 /* Is anything being shadowed? Invisible decls do not count. */
1963 for (b = I_SYMBOL_BINDING (DECL_NAME (new_decl)); b; b = b->shadowed)
1964 if (b->decl && b->decl != new_decl && !b->invisible)
1966 tree old_decl = b->decl;
1968 if (old_decl == error_mark_node)
1970 warning (OPT_Wshadow, "declaration of %q+D shadows previous "
1971 "non-variable", new_decl);
1972 break;
1974 else if (TREE_CODE (old_decl) == PARM_DECL)
1975 warning (OPT_Wshadow, "declaration of %q+D shadows a parameter",
1976 new_decl);
1977 else if (DECL_FILE_SCOPE_P (old_decl))
1978 warning (OPT_Wshadow, "declaration of %q+D shadows a global "
1979 "declaration", new_decl);
1980 else if (TREE_CODE (old_decl) == FUNCTION_DECL
1981 && DECL_BUILT_IN (old_decl))
1983 warning (OPT_Wshadow, "declaration of %q+D shadows "
1984 "a built-in function", new_decl);
1985 break;
1987 else
1988 warning (OPT_Wshadow, "declaration of %q+D shadows a previous local",
1989 new_decl);
1991 warning (OPT_Wshadow, "%Jshadowed declaration is here", old_decl);
1993 break;
1998 /* Subroutine of pushdecl.
2000 X is a TYPE_DECL for a typedef statement. Create a brand new
2001 ..._TYPE node (which will be just a variant of the existing
2002 ..._TYPE node with identical properties) and then install X
2003 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2005 The whole point here is to end up with a situation where each
2006 and every ..._TYPE node the compiler creates will be uniquely
2007 associated with AT MOST one node representing a typedef name.
2008 This way, even though the compiler substitutes corresponding
2009 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2010 early on, later parts of the compiler can always do the reverse
2011 translation and get back the corresponding typedef name. For
2012 example, given:
2014 typedef struct S MY_TYPE;
2015 MY_TYPE object;
2017 Later parts of the compiler might only know that `object' was of
2018 type `struct S' if it were not for code just below. With this
2019 code however, later parts of the compiler see something like:
2021 struct S' == struct S
2022 typedef struct S' MY_TYPE;
2023 struct S' object;
2025 And they can then deduce (from the node for type struct S') that
2026 the original object declaration was:
2028 MY_TYPE object;
2030 Being able to do this is important for proper support of protoize,
2031 and also for generating precise symbolic debugging information
2032 which takes full account of the programmer's (typedef) vocabulary.
2034 Obviously, we don't want to generate a duplicate ..._TYPE node if
2035 the TYPE_DECL node that we are now processing really represents a
2036 standard built-in type. */
2038 static void
2039 clone_underlying_type (tree x)
2041 if (DECL_IS_BUILTIN (x))
2043 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2044 TYPE_NAME (TREE_TYPE (x)) = x;
2046 else if (TREE_TYPE (x) != error_mark_node
2047 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2049 tree tt = TREE_TYPE (x);
2050 DECL_ORIGINAL_TYPE (x) = tt;
2051 tt = build_variant_type_copy (tt);
2052 TYPE_NAME (tt) = x;
2053 TREE_USED (tt) = TREE_USED (x);
2054 TREE_TYPE (x) = tt;
2058 /* Record a decl-node X as belonging to the current lexical scope.
2059 Check for errors (such as an incompatible declaration for the same
2060 name already seen in the same scope).
2062 Returns either X or an old decl for the same name.
2063 If an old decl is returned, it may have been smashed
2064 to agree with what X says. */
2066 tree
2067 pushdecl (tree x)
2069 tree name = DECL_NAME (x);
2070 struct c_scope *scope = current_scope;
2071 struct c_binding *b;
2072 bool nested = false;
2074 /* Must set DECL_CONTEXT for everything not at file scope or
2075 DECL_FILE_SCOPE_P won't work. Local externs don't count
2076 unless they have initializers (which generate code). */
2077 if (current_function_decl
2078 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
2079 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
2080 DECL_CONTEXT (x) = current_function_decl;
2082 /* If this is of variably modified type, prevent jumping into its
2083 scope. */
2084 if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == TYPE_DECL)
2085 && variably_modified_type_p (TREE_TYPE (x), NULL_TREE))
2086 c_begin_vm_scope (scope->depth);
2088 /* Anonymous decls are just inserted in the scope. */
2089 if (!name)
2091 bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
2092 return x;
2095 /* First, see if there is another declaration with the same name in
2096 the current scope. If there is, duplicate_decls may do all the
2097 work for us. If duplicate_decls returns false, that indicates
2098 two incompatible decls in the same scope; we are to silently
2099 replace the old one (duplicate_decls has issued all appropriate
2100 diagnostics). In particular, we should not consider possible
2101 duplicates in the external scope, or shadowing. */
2102 b = I_SYMBOL_BINDING (name);
2103 if (b && B_IN_SCOPE (b, scope))
2105 struct c_binding *b_ext, *b_use;
2106 tree type = TREE_TYPE (x);
2107 tree visdecl = b->decl;
2108 tree vistype = TREE_TYPE (visdecl);
2109 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
2110 && COMPLETE_TYPE_P (TREE_TYPE (x)))
2111 b->inner_comp = false;
2112 b_use = b;
2113 b_ext = b;
2114 /* If this is an external linkage declaration, we should check
2115 for compatibility with the type in the external scope before
2116 setting the type at this scope based on the visible
2117 information only. */
2118 if (TREE_PUBLIC (x) && TREE_PUBLIC (visdecl))
2120 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
2121 b_ext = b_ext->shadowed;
2122 if (b_ext)
2124 b_use = b_ext;
2125 if (b_use->type)
2126 TREE_TYPE (b_use->decl) = b_use->type;
2129 if (duplicate_decls (x, b_use->decl))
2131 if (b_use != b)
2133 /* Save the updated type in the external scope and
2134 restore the proper type for this scope. */
2135 tree thistype;
2136 if (comptypes (vistype, type))
2137 thistype = composite_type (vistype, type);
2138 else
2139 thistype = TREE_TYPE (b_use->decl);
2140 b_use->type = TREE_TYPE (b_use->decl);
2141 if (TREE_CODE (b_use->decl) == FUNCTION_DECL
2142 && DECL_BUILT_IN (b_use->decl))
2143 thistype
2144 = build_type_attribute_variant (thistype,
2145 TYPE_ATTRIBUTES
2146 (b_use->type));
2147 TREE_TYPE (b_use->decl) = thistype;
2149 return b_use->decl;
2151 else
2152 goto skip_external_and_shadow_checks;
2155 /* All declarations with external linkage, and all external
2156 references, go in the external scope, no matter what scope is
2157 current. However, the binding in that scope is ignored for
2158 purposes of normal name lookup. A separate binding structure is
2159 created in the requested scope; this governs the normal
2160 visibility of the symbol.
2162 The binding in the externals scope is used exclusively for
2163 detecting duplicate declarations of the same object, no matter
2164 what scope they are in; this is what we do here. (C99 6.2.7p2:
2165 All declarations that refer to the same object or function shall
2166 have compatible type; otherwise, the behavior is undefined.) */
2167 if (DECL_EXTERNAL (x) || scope == file_scope)
2169 tree type = TREE_TYPE (x);
2170 tree vistype = 0;
2171 tree visdecl = 0;
2172 bool type_saved = false;
2173 if (b && !B_IN_EXTERNAL_SCOPE (b)
2174 && (TREE_CODE (b->decl) == FUNCTION_DECL
2175 || TREE_CODE (b->decl) == VAR_DECL)
2176 && DECL_FILE_SCOPE_P (b->decl))
2178 visdecl = b->decl;
2179 vistype = TREE_TYPE (visdecl);
2181 if (scope != file_scope
2182 && !DECL_IN_SYSTEM_HEADER (x))
2183 warning (OPT_Wnested_externs, "nested extern declaration of %qD", x);
2185 while (b && !B_IN_EXTERNAL_SCOPE (b))
2187 /* If this decl might be modified, save its type. This is
2188 done here rather than when the decl is first bound
2189 because the type may change after first binding, through
2190 being completed or through attributes being added. If we
2191 encounter multiple such decls, only the first should have
2192 its type saved; the others will already have had their
2193 proper types saved and the types will not have changed as
2194 their scopes will not have been re-entered. */
2195 if (DECL_P (b->decl) && DECL_FILE_SCOPE_P (b->decl) && !type_saved)
2197 b->type = TREE_TYPE (b->decl);
2198 type_saved = true;
2200 if (B_IN_FILE_SCOPE (b)
2201 && TREE_CODE (b->decl) == VAR_DECL
2202 && TREE_STATIC (b->decl)
2203 && TREE_CODE (TREE_TYPE (b->decl)) == ARRAY_TYPE
2204 && !TYPE_DOMAIN (TREE_TYPE (b->decl))
2205 && TREE_CODE (type) == ARRAY_TYPE
2206 && TYPE_DOMAIN (type)
2207 && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
2208 && !integer_zerop (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
2210 /* Array type completed in inner scope, which should be
2211 diagnosed if the completion does not have size 1 and
2212 it does not get completed in the file scope. */
2213 b->inner_comp = true;
2215 b = b->shadowed;
2218 /* If a matching external declaration has been found, set its
2219 type to the composite of all the types of that declaration.
2220 After the consistency checks, it will be reset to the
2221 composite of the visible types only. */
2222 if (b && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2223 && b->type)
2224 TREE_TYPE (b->decl) = b->type;
2226 /* The point of the same_translation_unit_p check here is,
2227 we want to detect a duplicate decl for a construct like
2228 foo() { extern bar(); } ... static bar(); but not if
2229 they are in different translation units. In any case,
2230 the static does not go in the externals scope. */
2231 if (b
2232 && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2233 && duplicate_decls (x, b->decl))
2235 tree thistype;
2236 if (vistype)
2238 if (comptypes (vistype, type))
2239 thistype = composite_type (vistype, type);
2240 else
2241 thistype = TREE_TYPE (b->decl);
2243 else
2244 thistype = type;
2245 b->type = TREE_TYPE (b->decl);
2246 if (TREE_CODE (b->decl) == FUNCTION_DECL && DECL_BUILT_IN (b->decl))
2247 thistype
2248 = build_type_attribute_variant (thistype,
2249 TYPE_ATTRIBUTES (b->type));
2250 TREE_TYPE (b->decl) = thistype;
2251 bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
2252 return b->decl;
2254 else if (TREE_PUBLIC (x))
2256 if (visdecl && !b && duplicate_decls (x, visdecl))
2258 /* An external declaration at block scope referring to a
2259 visible entity with internal linkage. The composite
2260 type will already be correct for this scope, so we
2261 just need to fall through to make the declaration in
2262 this scope. */
2263 nested = true;
2264 x = visdecl;
2266 else
2268 bind (name, x, external_scope, /*invisible=*/true,
2269 /*nested=*/false);
2270 nested = true;
2275 if (TREE_CODE (x) != PARM_DECL)
2276 warn_if_shadowing (x);
2278 skip_external_and_shadow_checks:
2279 if (TREE_CODE (x) == TYPE_DECL)
2280 clone_underlying_type (x);
2282 bind (name, x, scope, /*invisible=*/false, nested);
2284 /* If x's type is incomplete because it's based on a
2285 structure or union which has not yet been fully declared,
2286 attach it to that structure or union type, so we can go
2287 back and complete the variable declaration later, if the
2288 structure or union gets fully declared.
2290 If the input is erroneous, we can have error_mark in the type
2291 slot (e.g. "f(void a, ...)") - that doesn't count as an
2292 incomplete type. */
2293 if (TREE_TYPE (x) != error_mark_node
2294 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2296 tree element = TREE_TYPE (x);
2298 while (TREE_CODE (element) == ARRAY_TYPE)
2299 element = TREE_TYPE (element);
2300 element = TYPE_MAIN_VARIANT (element);
2302 if ((TREE_CODE (element) == RECORD_TYPE
2303 || TREE_CODE (element) == UNION_TYPE)
2304 && (TREE_CODE (x) != TYPE_DECL
2305 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
2306 && !COMPLETE_TYPE_P (element))
2307 C_TYPE_INCOMPLETE_VARS (element)
2308 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
2310 return x;
2313 /* Record X as belonging to file scope.
2314 This is used only internally by the Objective-C front end,
2315 and is limited to its needs. duplicate_decls is not called;
2316 if there is any preexisting decl for this identifier, it is an ICE. */
2318 tree
2319 pushdecl_top_level (tree x)
2321 tree name;
2322 bool nested = false;
2323 gcc_assert (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL);
2325 name = DECL_NAME (x);
2327 gcc_assert (TREE_CODE (x) == CONST_DECL || !I_SYMBOL_BINDING (name));
2329 if (TREE_PUBLIC (x))
2331 bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
2332 nested = true;
2334 if (file_scope)
2335 bind (name, x, file_scope, /*invisible=*/false, nested);
2337 return x;
2340 static void
2341 implicit_decl_warning (tree id, tree olddecl)
2343 if (warn_implicit_function_declaration)
2345 if (flag_isoc99)
2346 pedwarn (G_("implicit declaration of function %qE"), id);
2347 else
2348 warning (OPT_Wimplicit_function_declaration,
2349 G_("implicit declaration of function %qE"), id);
2350 if (olddecl)
2351 locate_old_decl (olddecl, inform);
2355 /* Generate an implicit declaration for identifier FUNCTIONID as a
2356 function of type int (). */
2358 tree
2359 implicitly_declare (tree functionid)
2361 struct c_binding *b;
2362 tree decl = 0;
2363 tree asmspec_tree;
2365 for (b = I_SYMBOL_BINDING (functionid); b; b = b->shadowed)
2367 if (B_IN_SCOPE (b, external_scope))
2369 decl = b->decl;
2370 break;
2374 if (decl)
2376 if (decl == error_mark_node)
2377 return decl;
2379 /* FIXME: Objective-C has weird not-really-builtin functions
2380 which are supposed to be visible automatically. They wind up
2381 in the external scope because they're pushed before the file
2382 scope gets created. Catch this here and rebind them into the
2383 file scope. */
2384 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
2386 bind (functionid, decl, file_scope,
2387 /*invisible=*/false, /*nested=*/true);
2388 return decl;
2390 else
2392 tree newtype = default_function_type;
2393 if (b->type)
2394 TREE_TYPE (decl) = b->type;
2395 /* Implicit declaration of a function already declared
2396 (somehow) in a different scope, or as a built-in.
2397 If this is the first time this has happened, warn;
2398 then recycle the old declaration but with the new type. */
2399 if (!C_DECL_IMPLICIT (decl))
2401 implicit_decl_warning (functionid, decl);
2402 C_DECL_IMPLICIT (decl) = 1;
2404 if (DECL_BUILT_IN (decl))
2406 newtype = build_type_attribute_variant (newtype,
2407 TYPE_ATTRIBUTES
2408 (TREE_TYPE (decl)));
2409 if (!comptypes (newtype, TREE_TYPE (decl)))
2411 warning (0, "incompatible implicit declaration of built-in"
2412 " function %qD", decl);
2413 newtype = TREE_TYPE (decl);
2416 else
2418 if (!comptypes (newtype, TREE_TYPE (decl)))
2420 error ("incompatible implicit declaration of function %qD",
2421 decl);
2422 locate_old_decl (decl, error);
2425 b->type = TREE_TYPE (decl);
2426 TREE_TYPE (decl) = newtype;
2427 bind (functionid, decl, current_scope,
2428 /*invisible=*/false, /*nested=*/true);
2429 return decl;
2433 /* Not seen before. */
2434 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2435 DECL_EXTERNAL (decl) = 1;
2436 TREE_PUBLIC (decl) = 1;
2437 C_DECL_IMPLICIT (decl) = 1;
2438 implicit_decl_warning (functionid, 0);
2439 asmspec_tree = maybe_apply_renaming_pragma (decl, /*asmname=*/NULL);
2440 if (asmspec_tree)
2441 set_user_assembler_name (decl, TREE_STRING_POINTER (asmspec_tree));
2443 /* C89 says implicit declarations are in the innermost block.
2444 So we record the decl in the standard fashion. */
2445 decl = pushdecl (decl);
2447 /* No need to call objc_check_decl here - it's a function type. */
2448 rest_of_decl_compilation (decl, 0, 0);
2450 /* Write a record describing this implicit function declaration
2451 to the prototypes file (if requested). */
2452 gen_aux_info_record (decl, 0, 1, 0);
2454 /* Possibly apply some default attributes to this implicit declaration. */
2455 decl_attributes (&decl, NULL_TREE, 0);
2457 return decl;
2460 /* Issue an error message for a reference to an undeclared variable
2461 ID, including a reference to a builtin outside of function-call
2462 context. Establish a binding of the identifier to error_mark_node
2463 in an appropriate scope, which will suppress further errors for the
2464 same identifier. The error message should be given location LOC. */
2465 void
2466 undeclared_variable (tree id, location_t loc)
2468 static bool already = false;
2469 struct c_scope *scope;
2471 if (current_function_decl == 0)
2473 error ("%H%qE undeclared here (not in a function)", &loc, id);
2474 scope = current_scope;
2476 else
2478 error ("%H%qE undeclared (first use in this function)", &loc, id);
2480 if (!already)
2482 error ("%H(Each undeclared identifier is reported only once", &loc);
2483 error ("%Hfor each function it appears in.)", &loc);
2484 already = true;
2487 /* If we are parsing old-style parameter decls, current_function_decl
2488 will be nonnull but current_function_scope will be null. */
2489 scope = current_function_scope ? current_function_scope : current_scope;
2491 bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
2494 /* Subroutine of lookup_label, declare_label, define_label: construct a
2495 LABEL_DECL with all the proper frills. */
2497 static tree
2498 make_label (tree name, location_t location)
2500 tree label = build_decl (LABEL_DECL, name, void_type_node);
2502 DECL_CONTEXT (label) = current_function_decl;
2503 DECL_MODE (label) = VOIDmode;
2504 DECL_SOURCE_LOCATION (label) = location;
2506 return label;
2509 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2510 Create one if none exists so far for the current function.
2511 This is called when a label is used in a goto expression or
2512 has its address taken. */
2514 tree
2515 lookup_label (tree name)
2517 tree label;
2519 if (current_function_decl == 0)
2521 error ("label %qE referenced outside of any function", name);
2522 return 0;
2525 /* Use a label already defined or ref'd with this name, but not if
2526 it is inherited from a containing function and wasn't declared
2527 using __label__. */
2528 label = I_LABEL_DECL (name);
2529 if (label && (DECL_CONTEXT (label) == current_function_decl
2530 || C_DECLARED_LABEL_FLAG (label)))
2532 /* If the label has only been declared, update its apparent
2533 location to point here, for better diagnostics if it
2534 turns out not to have been defined. */
2535 if (!TREE_USED (label))
2536 DECL_SOURCE_LOCATION (label) = input_location;
2537 return label;
2540 /* No label binding for that identifier; make one. */
2541 label = make_label (name, input_location);
2543 /* Ordinary labels go in the current function scope. */
2544 bind (name, label, current_function_scope,
2545 /*invisible=*/false, /*nested=*/false);
2546 return label;
2549 /* Make a label named NAME in the current function, shadowing silently
2550 any that may be inherited from containing functions or containing
2551 scopes. This is called for __label__ declarations. */
2553 tree
2554 declare_label (tree name)
2556 struct c_binding *b = I_LABEL_BINDING (name);
2557 tree label;
2559 /* Check to make sure that the label hasn't already been declared
2560 at this scope */
2561 if (b && B_IN_CURRENT_SCOPE (b))
2563 error ("duplicate label declaration %qE", name);
2564 locate_old_decl (b->decl, error);
2566 /* Just use the previous declaration. */
2567 return b->decl;
2570 label = make_label (name, input_location);
2571 C_DECLARED_LABEL_FLAG (label) = 1;
2573 /* Declared labels go in the current scope. */
2574 bind (name, label, current_scope,
2575 /*invisible=*/false, /*nested=*/false);
2576 return label;
2579 /* Define a label, specifying the location in the source file.
2580 Return the LABEL_DECL node for the label, if the definition is valid.
2581 Otherwise return 0. */
2583 tree
2584 define_label (location_t location, tree name)
2586 /* Find any preexisting label with this name. It is an error
2587 if that label has already been defined in this function, or
2588 if there is a containing function with a declared label with
2589 the same name. */
2590 tree label = I_LABEL_DECL (name);
2591 struct c_label_list *nlist_se, *nlist_vm;
2593 if (label
2594 && ((DECL_CONTEXT (label) == current_function_decl
2595 && DECL_INITIAL (label) != 0)
2596 || (DECL_CONTEXT (label) != current_function_decl
2597 && C_DECLARED_LABEL_FLAG (label))))
2599 error ("%Hduplicate label %qD", &location, label);
2600 locate_old_decl (label, error);
2601 return 0;
2603 else if (label && DECL_CONTEXT (label) == current_function_decl)
2605 /* The label has been used or declared already in this function,
2606 but not defined. Update its location to point to this
2607 definition. */
2608 if (C_DECL_UNDEFINABLE_STMT_EXPR (label))
2609 error ("%Jjump into statement expression", label);
2610 if (C_DECL_UNDEFINABLE_VM (label))
2611 error ("%Jjump into scope of identifier with variably modified type",
2612 label);
2613 DECL_SOURCE_LOCATION (label) = location;
2615 else
2617 /* No label binding for that identifier; make one. */
2618 label = make_label (name, location);
2620 /* Ordinary labels go in the current function scope. */
2621 bind (name, label, current_function_scope,
2622 /*invisible=*/false, /*nested=*/false);
2625 if (!in_system_header && lookup_name (name))
2626 warning (OPT_Wtraditional, "%Htraditional C lacks a separate namespace "
2627 "for labels, identifier %qE conflicts", &location, name);
2629 nlist_se = XOBNEW (&parser_obstack, struct c_label_list);
2630 nlist_se->next = label_context_stack_se->labels_def;
2631 nlist_se->label = label;
2632 label_context_stack_se->labels_def = nlist_se;
2634 nlist_vm = XOBNEW (&parser_obstack, struct c_label_list);
2635 nlist_vm->next = label_context_stack_vm->labels_def;
2636 nlist_vm->label = label;
2637 label_context_stack_vm->labels_def = nlist_vm;
2639 /* Mark label as having been defined. */
2640 DECL_INITIAL (label) = error_mark_node;
2641 return label;
2644 /* Given NAME, an IDENTIFIER_NODE,
2645 return the structure (or union or enum) definition for that name.
2646 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2647 CODE says which kind of type the caller wants;
2648 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2649 If the wrong kind of type is found, an error is reported. */
2651 static tree
2652 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2654 struct c_binding *b = I_TAG_BINDING (name);
2655 int thislevel = 0;
2657 if (!b || !b->decl)
2658 return 0;
2660 /* We only care about whether it's in this level if
2661 thislevel_only was set or it might be a type clash. */
2662 if (thislevel_only || TREE_CODE (b->decl) != code)
2664 /* For our purposes, a tag in the external scope is the same as
2665 a tag in the file scope. (Primarily relevant to Objective-C
2666 and its builtin structure tags, which get pushed before the
2667 file scope is created.) */
2668 if (B_IN_CURRENT_SCOPE (b)
2669 || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
2670 thislevel = 1;
2673 if (thislevel_only && !thislevel)
2674 return 0;
2676 if (TREE_CODE (b->decl) != code)
2678 /* Definition isn't the kind we were looking for. */
2679 pending_invalid_xref = name;
2680 pending_invalid_xref_location = input_location;
2682 /* If in the same binding level as a declaration as a tag
2683 of a different type, this must not be allowed to
2684 shadow that tag, so give the error immediately.
2685 (For example, "struct foo; union foo;" is invalid.) */
2686 if (thislevel)
2687 pending_xref_error ();
2689 return b->decl;
2692 /* Print an error message now
2693 for a recent invalid struct, union or enum cross reference.
2694 We don't print them immediately because they are not invalid
2695 when used in the `struct foo;' construct for shadowing. */
2697 void
2698 pending_xref_error (void)
2700 if (pending_invalid_xref != 0)
2701 error ("%H%qE defined as wrong kind of tag",
2702 &pending_invalid_xref_location, pending_invalid_xref);
2703 pending_invalid_xref = 0;
2707 /* Look up NAME in the current scope and its superiors
2708 in the namespace of variables, functions and typedefs.
2709 Return a ..._DECL node of some kind representing its definition,
2710 or return 0 if it is undefined. */
2712 tree
2713 lookup_name (tree name)
2715 struct c_binding *b = I_SYMBOL_BINDING (name);
2716 if (b && !b->invisible)
2717 return b->decl;
2718 return 0;
2721 /* Similar to `lookup_name' but look only at the indicated scope. */
2723 static tree
2724 lookup_name_in_scope (tree name, struct c_scope *scope)
2726 struct c_binding *b;
2728 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2729 if (B_IN_SCOPE (b, scope))
2730 return b->decl;
2731 return 0;
2734 /* Create the predefined scalar types of C,
2735 and some nodes representing standard constants (0, 1, (void *) 0).
2736 Initialize the global scope.
2737 Make definitions for built-in primitive functions. */
2739 void
2740 c_init_decl_processing (void)
2742 location_t save_loc = input_location;
2744 /* Initialize reserved words for parser. */
2745 c_parse_init ();
2747 current_function_decl = 0;
2749 gcc_obstack_init (&parser_obstack);
2751 /* Make the externals scope. */
2752 push_scope ();
2753 external_scope = current_scope;
2755 /* Declarations from c_common_nodes_and_builtins must not be associated
2756 with this input file, lest we get differences between using and not
2757 using preprocessed headers. */
2758 #ifdef USE_MAPPED_LOCATION
2759 input_location = BUILTINS_LOCATION;
2760 #else
2761 input_location.file = "<built-in>";
2762 input_location.line = 0;
2763 #endif
2765 build_common_tree_nodes (flag_signed_char, false);
2767 c_common_nodes_and_builtins ();
2769 /* In C, comparisons and TRUTH_* expressions have type int. */
2770 truthvalue_type_node = integer_type_node;
2771 truthvalue_true_node = integer_one_node;
2772 truthvalue_false_node = integer_zero_node;
2774 /* Even in C99, which has a real boolean type. */
2775 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2776 boolean_type_node));
2778 input_location = save_loc;
2780 pedantic_lvalues = true;
2782 make_fname_decl = c_make_fname_decl;
2783 start_fname_decls ();
2786 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2787 decl, NAME is the initialization string and TYPE_DEP indicates whether
2788 NAME depended on the type of the function. As we don't yet implement
2789 delayed emission of static data, we mark the decl as emitted
2790 so it is not placed in the output. Anything using it must therefore pull
2791 out the STRING_CST initializer directly. FIXME. */
2793 static tree
2794 c_make_fname_decl (tree id, int type_dep)
2796 const char *name = fname_as_string (type_dep);
2797 tree decl, type, init;
2798 size_t length = strlen (name);
2800 type = build_array_type (char_type_node,
2801 build_index_type (size_int (length)));
2802 type = c_build_qualified_type (type, TYPE_QUAL_CONST);
2804 decl = build_decl (VAR_DECL, id, type);
2806 TREE_STATIC (decl) = 1;
2807 TREE_READONLY (decl) = 1;
2808 DECL_ARTIFICIAL (decl) = 1;
2810 init = build_string (length + 1, name);
2811 free (CONST_CAST (char *, name));
2812 TREE_TYPE (init) = type;
2813 DECL_INITIAL (decl) = init;
2815 TREE_USED (decl) = 1;
2817 if (current_function_decl
2818 /* For invalid programs like this:
2820 void foo()
2821 const char* p = __FUNCTION__;
2823 the __FUNCTION__ is believed to appear in K&R style function
2824 parameter declarator. In that case we still don't have
2825 function_scope. */
2826 && (!errorcount || current_function_scope))
2828 DECL_CONTEXT (decl) = current_function_decl;
2829 bind (id, decl, current_function_scope,
2830 /*invisible=*/false, /*nested=*/false);
2833 finish_decl (decl, init, NULL_TREE);
2835 return decl;
2838 tree
2839 c_builtin_function (tree decl)
2841 tree type = TREE_TYPE (decl);
2842 tree id = DECL_NAME (decl);
2844 const char *name = IDENTIFIER_POINTER (id);
2845 C_DECL_BUILTIN_PROTOTYPE (decl) = (TYPE_ARG_TYPES (type) != 0);
2847 /* Should never be called on a symbol with a preexisting meaning. */
2848 gcc_assert (!I_SYMBOL_BINDING (id));
2850 bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
2852 /* Builtins in the implementation namespace are made visible without
2853 needing to be explicitly declared. See push_file_scope. */
2854 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2856 TREE_CHAIN (decl) = visible_builtins;
2857 visible_builtins = decl;
2860 return decl;
2863 /* Called when a declaration is seen that contains no names to declare.
2864 If its type is a reference to a structure, union or enum inherited
2865 from a containing scope, shadow that tag name for the current scope
2866 with a forward reference.
2867 If its type defines a new named structure or union
2868 or defines an enum, it is valid but we need not do anything here.
2869 Otherwise, it is an error. */
2871 void
2872 shadow_tag (const struct c_declspecs *declspecs)
2874 shadow_tag_warned (declspecs, 0);
2877 /* WARNED is 1 if we have done a pedwarn, 2 if we have done a warning,
2878 but no pedwarn. */
2879 void
2880 shadow_tag_warned (const struct c_declspecs *declspecs, int warned)
2882 bool found_tag = false;
2884 if (declspecs->type && !declspecs->default_int_p && !declspecs->typedef_p)
2886 tree value = declspecs->type;
2887 enum tree_code code = TREE_CODE (value);
2889 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2890 /* Used to test also that TYPE_SIZE (value) != 0.
2891 That caused warning for `struct foo;' at top level in the file. */
2893 tree name = TYPE_NAME (value);
2894 tree t;
2896 found_tag = true;
2898 if (name == 0)
2900 if (warned != 1 && code != ENUMERAL_TYPE)
2901 /* Empty unnamed enum OK */
2903 pedwarn ("unnamed struct/union that defines no instances");
2904 warned = 1;
2907 else if (!declspecs->tag_defined_p
2908 && declspecs->storage_class != csc_none)
2910 if (warned != 1)
2911 pedwarn ("empty declaration with storage class specifier "
2912 "does not redeclare tag");
2913 warned = 1;
2914 pending_xref_error ();
2916 else if (!declspecs->tag_defined_p
2917 && (declspecs->const_p
2918 || declspecs->volatile_p
2919 || declspecs->restrict_p))
2921 if (warned != 1)
2922 pedwarn ("empty declaration with type qualifier "
2923 "does not redeclare tag");
2924 warned = 1;
2925 pending_xref_error ();
2927 else
2929 pending_invalid_xref = 0;
2930 t = lookup_tag (code, name, 1);
2932 if (t == 0)
2934 t = make_node (code);
2935 pushtag (name, t);
2939 else
2941 if (warned != 1 && !in_system_header)
2943 pedwarn ("useless type name in empty declaration");
2944 warned = 1;
2948 else if (warned != 1 && !in_system_header && declspecs->typedef_p)
2950 pedwarn ("useless type name in empty declaration");
2951 warned = 1;
2954 pending_invalid_xref = 0;
2956 if (declspecs->inline_p)
2958 error ("%<inline%> in empty declaration");
2959 warned = 1;
2962 if (current_scope == file_scope && declspecs->storage_class == csc_auto)
2964 error ("%<auto%> in file-scope empty declaration");
2965 warned = 1;
2968 if (current_scope == file_scope && declspecs->storage_class == csc_register)
2970 error ("%<register%> in file-scope empty declaration");
2971 warned = 1;
2974 if (!warned && !in_system_header && declspecs->storage_class != csc_none)
2976 warning (0, "useless storage class specifier in empty declaration");
2977 warned = 2;
2980 if (!warned && !in_system_header && declspecs->thread_p)
2982 warning (0, "useless %<__thread%> in empty declaration");
2983 warned = 2;
2986 if (!warned && !in_system_header && (declspecs->const_p
2987 || declspecs->volatile_p
2988 || declspecs->restrict_p))
2990 warning (0, "useless type qualifier in empty declaration");
2991 warned = 2;
2994 if (warned != 1)
2996 if (!found_tag)
2997 pedwarn ("empty declaration");
3002 /* Return the qualifiers from SPECS as a bitwise OR of TYPE_QUAL_*
3003 bits. SPECS represents declaration specifiers that the grammar
3004 only permits to contain type qualifiers and attributes. */
3007 quals_from_declspecs (const struct c_declspecs *specs)
3009 int quals = ((specs->const_p ? TYPE_QUAL_CONST : 0)
3010 | (specs->volatile_p ? TYPE_QUAL_VOLATILE : 0)
3011 | (specs->restrict_p ? TYPE_QUAL_RESTRICT : 0));
3012 gcc_assert (!specs->type
3013 && !specs->decl_attr
3014 && specs->typespec_word == cts_none
3015 && specs->storage_class == csc_none
3016 && !specs->typedef_p
3017 && !specs->explicit_signed_p
3018 && !specs->deprecated_p
3019 && !specs->long_p
3020 && !specs->long_long_p
3021 && !specs->short_p
3022 && !specs->signed_p
3023 && !specs->unsigned_p
3024 && !specs->complex_p
3025 && !specs->inline_p
3026 && !specs->thread_p);
3027 return quals;
3030 /* Construct an array declarator. EXPR is the expression inside [],
3031 or NULL_TREE. QUALS are the type qualifiers inside the [] (to be
3032 applied to the pointer to which a parameter array is converted).
3033 STATIC_P is true if "static" is inside the [], false otherwise.
3034 VLA_UNSPEC_P is true if the array is [*], a VLA of unspecified
3035 length which is nevertheless a complete type, false otherwise. The
3036 field for the contained declarator is left to be filled in by
3037 set_array_declarator_inner. */
3039 struct c_declarator *
3040 build_array_declarator (tree expr, struct c_declspecs *quals, bool static_p,
3041 bool vla_unspec_p)
3043 struct c_declarator *declarator = XOBNEW (&parser_obstack,
3044 struct c_declarator);
3045 declarator->kind = cdk_array;
3046 declarator->declarator = 0;
3047 declarator->u.array.dimen = expr;
3048 if (quals)
3050 declarator->u.array.attrs = quals->attrs;
3051 declarator->u.array.quals = quals_from_declspecs (quals);
3053 else
3055 declarator->u.array.attrs = NULL_TREE;
3056 declarator->u.array.quals = 0;
3058 declarator->u.array.static_p = static_p;
3059 declarator->u.array.vla_unspec_p = vla_unspec_p;
3060 if (pedantic && !flag_isoc99)
3062 if (static_p || quals != NULL)
3063 pedwarn ("ISO C90 does not support %<static%> or type "
3064 "qualifiers in parameter array declarators");
3065 if (vla_unspec_p)
3066 pedwarn ("ISO C90 does not support %<[*]%> array declarators");
3068 if (vla_unspec_p)
3070 if (!current_scope->parm_flag)
3072 /* C99 6.7.5.2p4 */
3073 error ("%<[*]%> not allowed in other than function prototype scope");
3074 declarator->u.array.vla_unspec_p = false;
3075 return NULL;
3077 current_scope->had_vla_unspec = true;
3079 return declarator;
3082 /* Set the contained declarator of an array declarator. DECL is the
3083 declarator, as constructed by build_array_declarator; INNER is what
3084 appears on the left of the []. ABSTRACT_P is true if it is an
3085 abstract declarator, false otherwise; this is used to reject static
3086 and type qualifiers in abstract declarators, where they are not in
3087 the C99 grammar (subject to possible change in DR#289). */
3089 struct c_declarator *
3090 set_array_declarator_inner (struct c_declarator *decl,
3091 struct c_declarator *inner, bool abstract_p)
3093 decl->declarator = inner;
3094 if (abstract_p && (decl->u.array.quals != TYPE_UNQUALIFIED
3095 || decl->u.array.attrs != NULL_TREE
3096 || decl->u.array.static_p))
3097 error ("static or type qualifiers in abstract declarator");
3098 return decl;
3101 /* INIT is a constructor that forms DECL's initializer. If the final
3102 element initializes a flexible array field, add the size of that
3103 initializer to DECL's size. */
3105 static void
3106 add_flexible_array_elts_to_size (tree decl, tree init)
3108 tree elt, type;
3110 if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init)))
3111 return;
3113 elt = VEC_last (constructor_elt, CONSTRUCTOR_ELTS (init))->value;
3114 type = TREE_TYPE (elt);
3115 if (TREE_CODE (type) == ARRAY_TYPE
3116 && TYPE_SIZE (type) == NULL_TREE
3117 && TYPE_DOMAIN (type) != NULL_TREE
3118 && TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL_TREE)
3120 complete_array_type (&type, elt, false);
3121 DECL_SIZE (decl)
3122 = size_binop (PLUS_EXPR, DECL_SIZE (decl), TYPE_SIZE (type));
3123 DECL_SIZE_UNIT (decl)
3124 = size_binop (PLUS_EXPR, DECL_SIZE_UNIT (decl), TYPE_SIZE_UNIT (type));
3128 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3130 tree
3131 groktypename (struct c_type_name *type_name)
3133 tree type;
3134 tree attrs = type_name->specs->attrs;
3136 type_name->specs->attrs = NULL_TREE;
3138 type = grokdeclarator (type_name->declarator, type_name->specs, TYPENAME,
3139 false, NULL, &attrs, DEPRECATED_NORMAL);
3141 /* Apply attributes. */
3142 decl_attributes (&type, attrs, 0);
3144 return type;
3147 /* Decode a declarator in an ordinary declaration or data definition.
3148 This is called as soon as the type information and variable name
3149 have been parsed, before parsing the initializer if any.
3150 Here we create the ..._DECL node, fill in its type,
3151 and put it on the list of decls for the current context.
3152 The ..._DECL node is returned as the value.
3154 Exception: for arrays where the length is not specified,
3155 the type is left null, to be filled in by `finish_decl'.
3157 Function definitions do not come here; they go to start_function
3158 instead. However, external and forward declarations of functions
3159 do go through here. Structure field declarations are done by
3160 grokfield and not through here. */
3162 tree
3163 start_decl (struct c_declarator *declarator, struct c_declspecs *declspecs,
3164 bool initialized, tree attributes)
3166 tree decl;
3167 tree tem;
3168 enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
3170 /* An object declared as __attribute__((deprecated)) suppresses
3171 warnings of uses of other deprecated items. */
3172 if (lookup_attribute ("deprecated", attributes))
3173 deprecated_state = DEPRECATED_SUPPRESS;
3175 decl = grokdeclarator (declarator, declspecs,
3176 NORMAL, initialized, NULL, &attributes,
3177 deprecated_state);
3178 if (!decl)
3179 return 0;
3181 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3182 && MAIN_NAME_P (DECL_NAME (decl)))
3183 warning (OPT_Wmain, "%q+D is usually a function", decl);
3185 if (initialized)
3186 /* Is it valid for this decl to have an initializer at all?
3187 If not, set INITIALIZED to zero, which will indirectly
3188 tell 'finish_decl' to ignore the initializer once it is parsed. */
3189 switch (TREE_CODE (decl))
3191 case TYPE_DECL:
3192 error ("typedef %qD is initialized (use __typeof__ instead)", decl);
3193 initialized = 0;
3194 break;
3196 case FUNCTION_DECL:
3197 error ("function %qD is initialized like a variable", decl);
3198 initialized = 0;
3199 break;
3201 case PARM_DECL:
3202 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3203 error ("parameter %qD is initialized", decl);
3204 initialized = 0;
3205 break;
3207 default:
3208 /* Don't allow initializations for incomplete types except for
3209 arrays which might be completed by the initialization. */
3211 /* This can happen if the array size is an undefined macro.
3212 We already gave a warning, so we don't need another one. */
3213 if (TREE_TYPE (decl) == error_mark_node)
3214 initialized = 0;
3215 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3217 /* A complete type is ok if size is fixed. */
3219 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3220 || C_DECL_VARIABLE_SIZE (decl))
3222 error ("variable-sized object may not be initialized");
3223 initialized = 0;
3226 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3228 error ("variable %qD has initializer but incomplete type", decl);
3229 initialized = 0;
3231 else if (C_DECL_VARIABLE_SIZE (decl))
3233 /* Although C99 is unclear about whether incomplete arrays
3234 of VLAs themselves count as VLAs, it does not make
3235 sense to permit them to be initialized given that
3236 ordinary VLAs may not be initialized. */
3237 error ("variable-sized object may not be initialized");
3238 initialized = 0;
3242 if (initialized)
3244 if (current_scope == file_scope)
3245 TREE_STATIC (decl) = 1;
3247 /* Tell 'pushdecl' this is an initialized decl
3248 even though we don't yet have the initializer expression.
3249 Also tell 'finish_decl' it may store the real initializer. */
3250 DECL_INITIAL (decl) = error_mark_node;
3253 /* If this is a function declaration, write a record describing it to the
3254 prototypes file (if requested). */
3256 if (TREE_CODE (decl) == FUNCTION_DECL)
3257 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3259 /* ANSI specifies that a tentative definition which is not merged with
3260 a non-tentative definition behaves exactly like a definition with an
3261 initializer equal to zero. (Section 3.7.2)
3263 -fno-common gives strict ANSI behavior, though this tends to break
3264 a large body of code that grew up without this rule.
3266 Thread-local variables are never common, since there's no entrenched
3267 body of code to break, and it allows more efficient variable references
3268 in the presence of dynamic linking. */
3270 if (TREE_CODE (decl) == VAR_DECL
3271 && !initialized
3272 && TREE_PUBLIC (decl)
3273 && !DECL_THREAD_LOCAL_P (decl)
3274 && !flag_no_common)
3275 DECL_COMMON (decl) = 1;
3277 /* Set attributes here so if duplicate decl, will have proper attributes. */
3278 decl_attributes (&decl, attributes, 0);
3280 /* Handle gnu_inline attribute. */
3281 if (declspecs->inline_p
3282 && !flag_gnu89_inline
3283 && TREE_CODE (decl) == FUNCTION_DECL
3284 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl)))
3286 if (declspecs->storage_class == csc_auto && current_scope != file_scope)
3288 else if (declspecs->storage_class != csc_static)
3289 DECL_EXTERNAL (decl) = !DECL_EXTERNAL (decl);
3292 if (TREE_CODE (decl) == FUNCTION_DECL
3293 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
3295 struct c_declarator *ce = declarator;
3297 if (ce->kind == cdk_pointer)
3298 ce = declarator->declarator;
3299 if (ce->kind == cdk_function)
3301 tree args = ce->u.arg_info->parms;
3302 for (; args; args = TREE_CHAIN (args))
3304 tree type = TREE_TYPE (args);
3305 if (type && INTEGRAL_TYPE_P (type)
3306 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
3307 DECL_ARG_TYPE (args) = integer_type_node;
3312 if (TREE_CODE (decl) == FUNCTION_DECL
3313 && DECL_DECLARED_INLINE_P (decl)
3314 && DECL_UNINLINABLE (decl)
3315 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3316 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
3317 decl);
3319 /* C99 6.7.4p3: An inline definition of a function with external
3320 linkage shall not contain a definition of a modifiable object
3321 with static storage duration... */
3322 if (TREE_CODE (decl) == VAR_DECL
3323 && current_scope != file_scope
3324 && TREE_STATIC (decl)
3325 && DECL_DECLARED_INLINE_P (current_function_decl)
3326 && DECL_EXTERNAL (current_function_decl))
3327 pedwarn ("%q+D is static but declared in inline function %qD "
3328 "which is not static", decl, current_function_decl);
3330 /* Add this decl to the current scope.
3331 TEM may equal DECL or it may be a previous decl of the same name. */
3332 tem = pushdecl (decl);
3334 if (initialized && DECL_EXTERNAL (tem))
3336 DECL_EXTERNAL (tem) = 0;
3337 TREE_STATIC (tem) = 1;
3340 return tem;
3343 /* Initialize EH if not initialized yet and exceptions are enabled. */
3345 void
3346 c_maybe_initialize_eh (void)
3348 if (!flag_exceptions || c_eh_initialized_p)
3349 return;
3351 c_eh_initialized_p = true;
3352 eh_personality_libfunc
3353 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3354 ? "__gcc_personality_sj0"
3355 : "__gcc_personality_v0");
3356 default_init_unwind_resume_libfunc ();
3357 using_eh_for_cleanups ();
3360 /* Finish processing of a declaration;
3361 install its initial value.
3362 If the length of an array type is not known before,
3363 it must be determined now, from the initial value, or it is an error. */
3365 void
3366 finish_decl (tree decl, tree init, tree asmspec_tree)
3368 tree type;
3369 int was_incomplete = (DECL_SIZE (decl) == 0);
3370 const char *asmspec = 0;
3372 /* If a name was specified, get the string. */
3373 if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL)
3374 && DECL_FILE_SCOPE_P (decl))
3375 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3376 if (asmspec_tree)
3377 asmspec = TREE_STRING_POINTER (asmspec_tree);
3379 /* If `start_decl' didn't like having an initialization, ignore it now. */
3380 if (init != 0 && DECL_INITIAL (decl) == 0)
3381 init = 0;
3383 /* Don't crash if parm is initialized. */
3384 if (TREE_CODE (decl) == PARM_DECL)
3385 init = 0;
3387 if (init)
3388 store_init_value (decl, init);
3390 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
3391 || TREE_CODE (decl) == FUNCTION_DECL
3392 || TREE_CODE (decl) == FIELD_DECL))
3393 objc_check_decl (decl);
3395 type = TREE_TYPE (decl);
3397 /* Deduce size of array from initialization, if not already known. */
3398 if (TREE_CODE (type) == ARRAY_TYPE
3399 && TYPE_DOMAIN (type) == 0
3400 && TREE_CODE (decl) != TYPE_DECL)
3402 bool do_default
3403 = (TREE_STATIC (decl)
3404 /* Even if pedantic, an external linkage array
3405 may have incomplete type at first. */
3406 ? pedantic && !TREE_PUBLIC (decl)
3407 : !DECL_EXTERNAL (decl));
3408 int failure
3409 = complete_array_type (&TREE_TYPE (decl), DECL_INITIAL (decl),
3410 do_default);
3412 /* Get the completed type made by complete_array_type. */
3413 type = TREE_TYPE (decl);
3415 switch (failure)
3417 case 1:
3418 error ("initializer fails to determine size of %q+D", decl);
3419 break;
3421 case 2:
3422 if (do_default)
3423 error ("array size missing in %q+D", decl);
3424 /* If a `static' var's size isn't known,
3425 make it extern as well as static, so it does not get
3426 allocated.
3427 If it is not `static', then do not mark extern;
3428 finish_incomplete_decl will give it a default size
3429 and it will get allocated. */
3430 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
3431 DECL_EXTERNAL (decl) = 1;
3432 break;
3434 case 3:
3435 error ("zero or negative size array %q+D", decl);
3436 break;
3438 case 0:
3439 /* For global variables, update the copy of the type that
3440 exists in the binding. */
3441 if (TREE_PUBLIC (decl))
3443 struct c_binding *b_ext = I_SYMBOL_BINDING (DECL_NAME (decl));
3444 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
3445 b_ext = b_ext->shadowed;
3446 if (b_ext)
3448 if (b_ext->type)
3449 b_ext->type = composite_type (b_ext->type, type);
3450 else
3451 b_ext->type = type;
3454 break;
3456 default:
3457 gcc_unreachable ();
3460 if (DECL_INITIAL (decl))
3461 TREE_TYPE (DECL_INITIAL (decl)) = type;
3463 layout_decl (decl, 0);
3466 if (TREE_CODE (decl) == VAR_DECL)
3468 if (init && TREE_CODE (init) == CONSTRUCTOR)
3469 add_flexible_array_elts_to_size (decl, init);
3471 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3472 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3473 layout_decl (decl, 0);
3475 if (DECL_SIZE (decl) == 0
3476 /* Don't give an error if we already gave one earlier. */
3477 && TREE_TYPE (decl) != error_mark_node
3478 && (TREE_STATIC (decl)
3479 /* A static variable with an incomplete type
3480 is an error if it is initialized.
3481 Also if it is not file scope.
3482 Otherwise, let it through, but if it is not `extern'
3483 then it may cause an error message later. */
3484 ? (DECL_INITIAL (decl) != 0
3485 || !DECL_FILE_SCOPE_P (decl))
3486 /* An automatic variable with an incomplete type
3487 is an error. */
3488 : !DECL_EXTERNAL (decl)))
3490 error ("storage size of %q+D isn%'t known", decl);
3491 TREE_TYPE (decl) = error_mark_node;
3494 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3495 && DECL_SIZE (decl) != 0)
3497 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3498 constant_expression_warning (DECL_SIZE (decl));
3499 else
3500 error ("storage size of %q+D isn%'t constant", decl);
3503 if (TREE_USED (type))
3504 TREE_USED (decl) = 1;
3507 /* If this is a function and an assembler name is specified, reset DECL_RTL
3508 so we can give it its new name. Also, update built_in_decls if it
3509 was a normal built-in. */
3510 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3512 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
3513 set_builtin_user_assembler_name (decl, asmspec);
3514 set_user_assembler_name (decl, asmspec);
3517 /* If #pragma weak was used, mark the decl weak now. */
3518 maybe_apply_pragma_weak (decl);
3520 /* Output the assembler code and/or RTL code for variables and functions,
3521 unless the type is an undefined structure or union.
3522 If not, it will get done when the type is completed. */
3524 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3526 /* Determine the ELF visibility. */
3527 if (TREE_PUBLIC (decl))
3528 c_determine_visibility (decl);
3530 /* This is a no-op in c-lang.c or something real in objc-act.c. */
3531 if (c_dialect_objc ())
3532 objc_check_decl (decl);
3534 if (asmspec)
3536 /* If this is not a static variable, issue a warning.
3537 It doesn't make any sense to give an ASMSPEC for an
3538 ordinary, non-register local variable. Historically,
3539 GCC has accepted -- but ignored -- the ASMSPEC in
3540 this case. */
3541 if (!DECL_FILE_SCOPE_P (decl)
3542 && TREE_CODE (decl) == VAR_DECL
3543 && !C_DECL_REGISTER (decl)
3544 && !TREE_STATIC (decl))
3545 warning (0, "ignoring asm-specifier for non-static local "
3546 "variable %q+D", decl);
3547 else
3548 set_user_assembler_name (decl, asmspec);
3551 if (DECL_FILE_SCOPE_P (decl))
3553 if (DECL_INITIAL (decl) == NULL_TREE
3554 || DECL_INITIAL (decl) == error_mark_node)
3555 /* Don't output anything
3556 when a tentative file-scope definition is seen.
3557 But at end of compilation, do output code for them. */
3558 DECL_DEFER_OUTPUT (decl) = 1;
3559 rest_of_decl_compilation (decl, true, 0);
3561 else
3563 /* In conjunction with an ASMSPEC, the `register'
3564 keyword indicates that we should place the variable
3565 in a particular register. */
3566 if (asmspec && C_DECL_REGISTER (decl))
3568 DECL_HARD_REGISTER (decl) = 1;
3569 /* This cannot be done for a structure with volatile
3570 fields, on which DECL_REGISTER will have been
3571 reset. */
3572 if (!DECL_REGISTER (decl))
3573 error ("cannot put object with volatile field into register");
3576 if (TREE_CODE (decl) != FUNCTION_DECL)
3578 /* If we're building a variable sized type, and we might be
3579 reachable other than via the top of the current binding
3580 level, then create a new BIND_EXPR so that we deallocate
3581 the object at the right time. */
3582 /* Note that DECL_SIZE can be null due to errors. */
3583 if (DECL_SIZE (decl)
3584 && !TREE_CONSTANT (DECL_SIZE (decl))
3585 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
3587 tree bind;
3588 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
3589 TREE_SIDE_EFFECTS (bind) = 1;
3590 add_stmt (bind);
3591 BIND_EXPR_BODY (bind) = push_stmt_list ();
3593 add_stmt (build_stmt (DECL_EXPR, decl));
3598 if (!DECL_FILE_SCOPE_P (decl))
3600 /* Recompute the RTL of a local array now
3601 if it used to be an incomplete type. */
3602 if (was_incomplete
3603 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
3605 /* If we used it already as memory, it must stay in memory. */
3606 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3607 /* If it's still incomplete now, no init will save it. */
3608 if (DECL_SIZE (decl) == 0)
3609 DECL_INITIAL (decl) = 0;
3614 /* If this was marked 'used', be sure it will be output. */
3615 if (!flag_unit_at_a_time && lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
3616 mark_decl_referenced (decl);
3618 if (TREE_CODE (decl) == TYPE_DECL)
3620 if (!DECL_FILE_SCOPE_P (decl)
3621 && variably_modified_type_p (TREE_TYPE (decl), NULL_TREE))
3622 add_stmt (build_stmt (DECL_EXPR, decl));
3624 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl), 0);
3627 /* At the end of a declaration, throw away any variable type sizes
3628 of types defined inside that declaration. There is no use
3629 computing them in the following function definition. */
3630 if (current_scope == file_scope)
3631 get_pending_sizes ();
3633 /* Install a cleanup (aka destructor) if one was given. */
3634 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
3636 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
3637 if (attr)
3639 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
3640 tree cleanup_decl = lookup_name (cleanup_id);
3641 tree cleanup;
3643 /* Build "cleanup(&decl)" for the destructor. */
3644 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3645 cleanup = build_tree_list (NULL_TREE, cleanup);
3646 cleanup = build_function_call (cleanup_decl, cleanup);
3648 /* Don't warn about decl unused; the cleanup uses it. */
3649 TREE_USED (decl) = 1;
3650 TREE_USED (cleanup_decl) = 1;
3652 /* Initialize EH, if we've been told to do so. */
3653 c_maybe_initialize_eh ();
3655 push_cleanup (decl, cleanup, false);
3660 /* Given a parsed parameter declaration, decode it into a PARM_DECL. */
3662 tree
3663 grokparm (const struct c_parm *parm)
3665 tree attrs = parm->attrs;
3666 tree decl = grokdeclarator (parm->declarator, parm->specs, PARM, false,
3667 NULL, &attrs, DEPRECATED_NORMAL);
3669 decl_attributes (&decl, attrs, 0);
3671 return decl;
3674 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3675 and push that on the current scope. */
3677 void
3678 push_parm_decl (const struct c_parm *parm)
3680 tree attrs = parm->attrs;
3681 tree decl;
3683 decl = grokdeclarator (parm->declarator, parm->specs, PARM, false, NULL,
3684 &attrs, DEPRECATED_NORMAL);
3685 decl_attributes (&decl, attrs, 0);
3687 decl = pushdecl (decl);
3689 finish_decl (decl, NULL_TREE, NULL_TREE);
3692 /* Mark all the parameter declarations to date as forward decls.
3693 Also diagnose use of this extension. */
3695 void
3696 mark_forward_parm_decls (void)
3698 struct c_binding *b;
3700 if (pedantic && !current_scope->warned_forward_parm_decls)
3702 pedwarn ("ISO C forbids forward parameter declarations");
3703 current_scope->warned_forward_parm_decls = true;
3706 for (b = current_scope->bindings; b; b = b->prev)
3707 if (TREE_CODE (b->decl) == PARM_DECL)
3708 TREE_ASM_WRITTEN (b->decl) = 1;
3711 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3712 literal, which may be an incomplete array type completed by the
3713 initializer; INIT is a CONSTRUCTOR that initializes the compound
3714 literal. */
3716 tree
3717 build_compound_literal (tree type, tree init)
3719 /* We do not use start_decl here because we have a type, not a declarator;
3720 and do not use finish_decl because the decl should be stored inside
3721 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3722 tree decl;
3723 tree complit;
3724 tree stmt;
3726 if (type == error_mark_node)
3727 return error_mark_node;
3729 decl = build_decl (VAR_DECL, NULL_TREE, type);
3730 DECL_EXTERNAL (decl) = 0;
3731 TREE_PUBLIC (decl) = 0;
3732 TREE_STATIC (decl) = (current_scope == file_scope);
3733 DECL_CONTEXT (decl) = current_function_decl;
3734 TREE_USED (decl) = 1;
3735 TREE_TYPE (decl) = type;
3736 TREE_READONLY (decl) = TYPE_READONLY (type);
3737 store_init_value (decl, init);
3739 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3741 int failure = complete_array_type (&TREE_TYPE (decl),
3742 DECL_INITIAL (decl), true);
3743 gcc_assert (!failure);
3745 type = TREE_TYPE (decl);
3746 TREE_TYPE (DECL_INITIAL (decl)) = type;
3749 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3750 return error_mark_node;
3752 stmt = build_stmt (DECL_EXPR, decl);
3753 complit = build1 (COMPOUND_LITERAL_EXPR, type, stmt);
3754 TREE_SIDE_EFFECTS (complit) = 1;
3756 layout_decl (decl, 0);
3758 if (TREE_STATIC (decl))
3760 /* This decl needs a name for the assembler output. */
3761 set_compound_literal_name (decl);
3762 DECL_DEFER_OUTPUT (decl) = 1;
3763 DECL_COMDAT (decl) = 1;
3764 DECL_ARTIFICIAL (decl) = 1;
3765 DECL_IGNORED_P (decl) = 1;
3766 pushdecl (decl);
3767 rest_of_decl_compilation (decl, 1, 0);
3770 return complit;
3773 /* Determine whether TYPE is a structure with a flexible array member,
3774 or a union containing such a structure (possibly recursively). */
3776 static bool
3777 flexible_array_type_p (tree type)
3779 tree x;
3780 switch (TREE_CODE (type))
3782 case RECORD_TYPE:
3783 x = TYPE_FIELDS (type);
3784 if (x == NULL_TREE)
3785 return false;
3786 while (TREE_CHAIN (x) != NULL_TREE)
3787 x = TREE_CHAIN (x);
3788 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3789 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3790 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3791 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3792 return true;
3793 return false;
3794 case UNION_TYPE:
3795 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3797 if (flexible_array_type_p (TREE_TYPE (x)))
3798 return true;
3800 return false;
3801 default:
3802 return false;
3806 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3807 replacing with appropriate values if they are invalid. */
3808 static void
3809 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3811 tree type_mv;
3812 unsigned int max_width;
3813 unsigned HOST_WIDE_INT w;
3814 const char *name = orig_name ? orig_name: _("<anonymous>");
3816 /* Detect and ignore out of range field width and process valid
3817 field widths. */
3818 if (!INTEGRAL_TYPE_P (TREE_TYPE (*width))
3819 || TREE_CODE (*width) != INTEGER_CST)
3821 error ("bit-field %qs width not an integer constant", name);
3822 *width = integer_one_node;
3824 else
3826 constant_expression_warning (*width);
3827 if (tree_int_cst_sgn (*width) < 0)
3829 error ("negative width in bit-field %qs", name);
3830 *width = integer_one_node;
3832 else if (integer_zerop (*width) && orig_name)
3834 error ("zero width for bit-field %qs", name);
3835 *width = integer_one_node;
3839 /* Detect invalid bit-field type. */
3840 if (TREE_CODE (*type) != INTEGER_TYPE
3841 && TREE_CODE (*type) != BOOLEAN_TYPE
3842 && TREE_CODE (*type) != ENUMERAL_TYPE)
3844 error ("bit-field %qs has invalid type", name);
3845 *type = unsigned_type_node;
3848 type_mv = TYPE_MAIN_VARIANT (*type);
3849 if (pedantic
3850 && !in_system_header
3851 && type_mv != integer_type_node
3852 && type_mv != unsigned_type_node
3853 && type_mv != boolean_type_node)
3854 pedwarn ("type of bit-field %qs is a GCC extension", name);
3856 max_width = TYPE_PRECISION (*type);
3858 if (0 < compare_tree_int (*width, max_width))
3860 error ("width of %qs exceeds its type", name);
3861 w = max_width;
3862 *width = build_int_cst (NULL_TREE, w);
3864 else
3865 w = tree_low_cst (*width, 1);
3867 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3869 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3870 if (!lt
3871 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3872 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3873 warning (0, "%qs is narrower than values of its type", name);
3879 /* Print warning about variable length array if necessary. */
3881 static void
3882 warn_variable_length_array (const char *name, tree size)
3884 int ped = !flag_isoc99 && pedantic && warn_vla != 0;
3885 int const_size = TREE_CONSTANT (size);
3887 if (ped)
3889 if (const_size)
3891 if (name)
3892 pedwarn ("ISO C90 forbids array %qs whose size "
3893 "can%'t be evaluated",
3894 name);
3895 else
3896 pedwarn ("ISO C90 forbids array whose size "
3897 "can%'t be evaluated");
3899 else
3901 if (name)
3902 pedwarn ("ISO C90 forbids variable length array %qs",
3903 name);
3904 else
3905 pedwarn ("ISO C90 forbids variable length array");
3908 else if (warn_vla > 0)
3910 if (const_size)
3912 if (name)
3913 warning (OPT_Wvla,
3914 "the size of array %qs can"
3915 "%'t be evaluated", name);
3916 else
3917 warning (OPT_Wvla,
3918 "the size of array can %'t be evaluated");
3920 else
3922 if (name)
3923 warning (OPT_Wvla,
3924 "variable length array %qs is used",
3925 name);
3926 else
3927 warning (OPT_Wvla,
3928 "variable length array is used");
3933 /* Given declspecs and a declarator,
3934 determine the name and type of the object declared
3935 and construct a ..._DECL node for it.
3936 (In one case we can return a ..._TYPE node instead.
3937 For invalid input we sometimes return 0.)
3939 DECLSPECS is a c_declspecs structure for the declaration specifiers.
3941 DECL_CONTEXT says which syntactic context this declaration is in:
3942 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3943 FUNCDEF for a function definition. Like NORMAL but a few different
3944 error messages in each case. Return value may be zero meaning
3945 this definition is too screwy to try to parse.
3946 PARM for a parameter declaration (either within a function prototype
3947 or before a function body). Make a PARM_DECL, or return void_type_node.
3948 TYPENAME if for a typename (in a cast or sizeof).
3949 Don't make a DECL node; just return the ..._TYPE node.
3950 FIELD for a struct or union field; make a FIELD_DECL.
3951 INITIALIZED is true if the decl has an initializer.
3952 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3953 representing the width of the bit-field.
3954 DECL_ATTRS points to the list of attributes that should be added to this
3955 decl. Any nested attributes that belong on the decl itself will be
3956 added to this list.
3957 DEPRECATED_STATE is a deprecated_states value indicating whether
3958 deprecation warnings should be suppressed.
3960 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3961 It may also be so in the PARM case, for a prototype where the
3962 argument type is specified but not the name.
3964 This function is where the complicated C meanings of `static'
3965 and `extern' are interpreted. */
3967 static tree
3968 grokdeclarator (const struct c_declarator *declarator,
3969 struct c_declspecs *declspecs,
3970 enum decl_context decl_context, bool initialized, tree *width,
3971 tree *decl_attrs, enum deprecated_states deprecated_state)
3973 tree type = declspecs->type;
3974 bool threadp = declspecs->thread_p;
3975 enum c_storage_class storage_class = declspecs->storage_class;
3976 int constp;
3977 int restrictp;
3978 int volatilep;
3979 int type_quals = TYPE_UNQUALIFIED;
3980 const char *name, *orig_name;
3981 tree typedef_type = 0;
3982 bool funcdef_flag = false;
3983 bool funcdef_syntax = false;
3984 int size_varies = 0;
3985 tree decl_attr = declspecs->decl_attr;
3986 int array_ptr_quals = TYPE_UNQUALIFIED;
3987 tree array_ptr_attrs = NULL_TREE;
3988 int array_parm_static = 0;
3989 bool array_parm_vla_unspec_p = false;
3990 tree returned_attrs = NULL_TREE;
3991 bool bitfield = width != NULL;
3992 tree element_type;
3993 struct c_arg_info *arg_info = 0;
3995 if (decl_context == FUNCDEF)
3996 funcdef_flag = true, decl_context = NORMAL;
3998 /* Look inside a declarator for the name being declared
3999 and get it as a string, for an error message. */
4001 const struct c_declarator *decl = declarator;
4002 name = 0;
4004 while (decl)
4005 switch (decl->kind)
4007 case cdk_function:
4008 case cdk_array:
4009 case cdk_pointer:
4010 funcdef_syntax = (decl->kind == cdk_function);
4011 decl = decl->declarator;
4012 break;
4014 case cdk_attrs:
4015 decl = decl->declarator;
4016 break;
4018 case cdk_id:
4019 if (decl->u.id)
4020 name = IDENTIFIER_POINTER (decl->u.id);
4021 decl = 0;
4022 break;
4024 default:
4025 gcc_unreachable ();
4027 orig_name = name;
4028 if (name == 0)
4029 name = "type name";
4032 /* A function definition's declarator must have the form of
4033 a function declarator. */
4035 if (funcdef_flag && !funcdef_syntax)
4036 return 0;
4038 /* If this looks like a function definition, make it one,
4039 even if it occurs where parms are expected.
4040 Then store_parm_decls will reject it and not use it as a parm. */
4041 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
4042 decl_context = PARM;
4044 if (declspecs->deprecated_p && deprecated_state != DEPRECATED_SUPPRESS)
4045 warn_deprecated_use (declspecs->type);
4047 if ((decl_context == NORMAL || decl_context == FIELD)
4048 && current_scope == file_scope
4049 && variably_modified_type_p (type, NULL_TREE))
4051 error ("variably modified %qs at file scope", name);
4052 type = integer_type_node;
4055 typedef_type = type;
4056 size_varies = C_TYPE_VARIABLE_SIZE (type);
4058 /* Diagnose defaulting to "int". */
4060 if (declspecs->default_int_p && !in_system_header)
4062 /* Issue a warning if this is an ISO C 99 program or if
4063 -Wreturn-type and this is a function, or if -Wimplicit;
4064 prefer the former warning since it is more explicit. */
4065 if ((warn_implicit_int || warn_return_type || flag_isoc99)
4066 && funcdef_flag)
4067 warn_about_return_type = 1;
4068 else if (warn_implicit_int || flag_isoc99)
4069 pedwarn_c99 ("type defaults to %<int%> in declaration of %qs", name);
4072 /* Adjust the type if a bit-field is being declared,
4073 -funsigned-bitfields applied and the type is not explicitly
4074 "signed". */
4075 if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
4076 && TREE_CODE (type) == INTEGER_TYPE)
4077 type = c_common_unsigned_type (type);
4079 /* Figure out the type qualifiers for the declaration. There are
4080 two ways a declaration can become qualified. One is something
4081 like `const int i' where the `const' is explicit. Another is
4082 something like `typedef const int CI; CI i' where the type of the
4083 declaration contains the `const'. A third possibility is that
4084 there is a type qualifier on the element type of a typedefed
4085 array type, in which case we should extract that qualifier so
4086 that c_apply_type_quals_to_decls receives the full list of
4087 qualifiers to work with (C90 is not entirely clear about whether
4088 duplicate qualifiers should be diagnosed in this case, but it
4089 seems most appropriate to do so). */
4090 element_type = strip_array_types (type);
4091 constp = declspecs->const_p + TYPE_READONLY (element_type);
4092 restrictp = declspecs->restrict_p + TYPE_RESTRICT (element_type);
4093 volatilep = declspecs->volatile_p + TYPE_VOLATILE (element_type);
4094 if (pedantic && !flag_isoc99)
4096 if (constp > 1)
4097 pedwarn ("duplicate %<const%>");
4098 if (restrictp > 1)
4099 pedwarn ("duplicate %<restrict%>");
4100 if (volatilep > 1)
4101 pedwarn ("duplicate %<volatile%>");
4103 if (!flag_gen_aux_info && (TYPE_QUALS (element_type)))
4104 type = TYPE_MAIN_VARIANT (type);
4105 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4106 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4107 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4109 /* Warn about storage classes that are invalid for certain
4110 kinds of declarations (parameters, typenames, etc.). */
4112 if (funcdef_flag
4113 && (threadp
4114 || storage_class == csc_auto
4115 || storage_class == csc_register
4116 || storage_class == csc_typedef))
4118 if (storage_class == csc_auto
4119 && (pedantic || current_scope == file_scope))
4120 pedwarn ("function definition declared %<auto%>");
4121 if (storage_class == csc_register)
4122 error ("function definition declared %<register%>");
4123 if (storage_class == csc_typedef)
4124 error ("function definition declared %<typedef%>");
4125 if (threadp)
4126 error ("function definition declared %<__thread%>");
4127 threadp = false;
4128 if (storage_class == csc_auto
4129 || storage_class == csc_register
4130 || storage_class == csc_typedef)
4131 storage_class = csc_none;
4133 else if (decl_context != NORMAL && (storage_class != csc_none || threadp))
4135 if (decl_context == PARM && storage_class == csc_register)
4137 else
4139 switch (decl_context)
4141 case FIELD:
4142 error ("storage class specified for structure field %qs",
4143 name);
4144 break;
4145 case PARM:
4146 error ("storage class specified for parameter %qs", name);
4147 break;
4148 default:
4149 error ("storage class specified for typename");
4150 break;
4152 storage_class = csc_none;
4153 threadp = false;
4156 else if (storage_class == csc_extern
4157 && initialized
4158 && !funcdef_flag)
4160 /* 'extern' with initialization is invalid if not at file scope. */
4161 if (current_scope == file_scope)
4163 /* It is fine to have 'extern const' when compiling at C
4164 and C++ intersection. */
4165 if (!(warn_cxx_compat && constp))
4166 warning (0, "%qs initialized and declared %<extern%>", name);
4168 else
4169 error ("%qs has both %<extern%> and initializer", name);
4171 else if (current_scope == file_scope)
4173 if (storage_class == csc_auto)
4174 error ("file-scope declaration of %qs specifies %<auto%>", name);
4175 if (pedantic && storage_class == csc_register)
4176 pedwarn ("file-scope declaration of %qs specifies %<register%>", name);
4178 else
4180 if (storage_class == csc_extern && funcdef_flag)
4181 error ("nested function %qs declared %<extern%>", name);
4182 else if (threadp && storage_class == csc_none)
4184 error ("function-scope %qs implicitly auto and declared "
4185 "%<__thread%>",
4186 name);
4187 threadp = false;
4191 /* Now figure out the structure of the declarator proper.
4192 Descend through it, creating more complex types, until we reach
4193 the declared identifier (or NULL_TREE, in an absolute declarator).
4194 At each stage we maintain an unqualified version of the type
4195 together with any qualifiers that should be applied to it with
4196 c_build_qualified_type; this way, array types including
4197 multidimensional array types are first built up in unqualified
4198 form and then the qualified form is created with
4199 TYPE_MAIN_VARIANT pointing to the unqualified form. */
4201 while (declarator && declarator->kind != cdk_id)
4203 if (type == error_mark_node)
4205 declarator = declarator->declarator;
4206 continue;
4209 /* Each level of DECLARATOR is either a cdk_array (for ...[..]),
4210 a cdk_pointer (for *...),
4211 a cdk_function (for ...(...)),
4212 a cdk_attrs (for nested attributes),
4213 or a cdk_id (for the name being declared
4214 or the place in an absolute declarator
4215 where the name was omitted).
4216 For the last case, we have just exited the loop.
4218 At this point, TYPE is the type of elements of an array,
4219 or for a function to return, or for a pointer to point to.
4220 After this sequence of ifs, TYPE is the type of the
4221 array or function or pointer, and DECLARATOR has had its
4222 outermost layer removed. */
4224 if (array_ptr_quals != TYPE_UNQUALIFIED
4225 || array_ptr_attrs != NULL_TREE
4226 || array_parm_static)
4228 /* Only the innermost declarator (making a parameter be of
4229 array type which is converted to pointer type)
4230 may have static or type qualifiers. */
4231 error ("static or type qualifiers in non-parameter array declarator");
4232 array_ptr_quals = TYPE_UNQUALIFIED;
4233 array_ptr_attrs = NULL_TREE;
4234 array_parm_static = 0;
4237 switch (declarator->kind)
4239 case cdk_attrs:
4241 /* A declarator with embedded attributes. */
4242 tree attrs = declarator->u.attrs;
4243 const struct c_declarator *inner_decl;
4244 int attr_flags = 0;
4245 declarator = declarator->declarator;
4246 inner_decl = declarator;
4247 while (inner_decl->kind == cdk_attrs)
4248 inner_decl = inner_decl->declarator;
4249 if (inner_decl->kind == cdk_id)
4250 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4251 else if (inner_decl->kind == cdk_function)
4252 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4253 else if (inner_decl->kind == cdk_array)
4254 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4255 returned_attrs = decl_attributes (&type,
4256 chainon (returned_attrs, attrs),
4257 attr_flags);
4258 break;
4260 case cdk_array:
4262 tree itype = NULL_TREE;
4263 tree size = declarator->u.array.dimen;
4264 /* The index is a signed object `sizetype' bits wide. */
4265 tree index_type = c_common_signed_type (sizetype);
4267 array_ptr_quals = declarator->u.array.quals;
4268 array_ptr_attrs = declarator->u.array.attrs;
4269 array_parm_static = declarator->u.array.static_p;
4270 array_parm_vla_unspec_p = declarator->u.array.vla_unspec_p;
4272 declarator = declarator->declarator;
4274 /* Check for some types that there cannot be arrays of. */
4276 if (VOID_TYPE_P (type))
4278 error ("declaration of %qs as array of voids", name);
4279 type = error_mark_node;
4282 if (TREE_CODE (type) == FUNCTION_TYPE)
4284 error ("declaration of %qs as array of functions", name);
4285 type = error_mark_node;
4288 if (pedantic && !in_system_header && flexible_array_type_p (type))
4289 pedwarn ("invalid use of structure with flexible array member");
4291 if (size == error_mark_node)
4292 type = error_mark_node;
4294 if (type == error_mark_node)
4295 continue;
4297 /* If size was specified, set ITYPE to a range-type for
4298 that size. Otherwise, ITYPE remains null. finish_decl
4299 may figure it out from an initial value. */
4301 if (size)
4303 /* Strip NON_LVALUE_EXPRs since we aren't using as an
4304 lvalue. */
4305 STRIP_TYPE_NOPS (size);
4307 if (!INTEGRAL_TYPE_P (TREE_TYPE (size)))
4309 error ("size of array %qs has non-integer type", name);
4310 size = integer_one_node;
4313 if (pedantic && integer_zerop (size))
4314 pedwarn ("ISO C forbids zero-size array %qs", name);
4316 if (TREE_CODE (size) == INTEGER_CST)
4318 constant_expression_warning (size);
4319 if (tree_int_cst_sgn (size) < 0)
4321 error ("size of array %qs is negative", name);
4322 size = integer_one_node;
4325 else if ((decl_context == NORMAL || decl_context == FIELD)
4326 && current_scope == file_scope)
4328 error ("variably modified %qs at file scope", name);
4329 size = integer_one_node;
4331 else
4333 /* Make sure the array size remains visibly
4334 nonconstant even if it is (eg) a const variable
4335 with known value. */
4336 size_varies = 1;
4337 warn_variable_length_array (orig_name, size);
4340 if (integer_zerop (size))
4342 /* A zero-length array cannot be represented with
4343 an unsigned index type, which is what we'll
4344 get with build_index_type. Create an
4345 open-ended range instead. */
4346 itype = build_range_type (sizetype, size, NULL_TREE);
4348 else
4350 /* Arrange for the SAVE_EXPR on the inside of the
4351 MINUS_EXPR, which allows the -1 to get folded
4352 with the +1 that happens when building TYPE_SIZE. */
4353 if (size_varies)
4354 size = variable_size (size);
4356 /* Compute the maximum valid index, that is, size
4357 - 1. Do the calculation in index_type, so that
4358 if it is a variable the computations will be
4359 done in the proper mode. */
4360 itype = fold_build2 (MINUS_EXPR, index_type,
4361 convert (index_type, size),
4362 convert (index_type,
4363 size_one_node));
4365 /* If that overflowed, the array is too big. ???
4366 While a size of INT_MAX+1 technically shouldn't
4367 cause an overflow (because we subtract 1), the
4368 overflow is recorded during the conversion to
4369 index_type, before the subtraction. Handling
4370 this case seems like an unnecessary
4371 complication. */
4372 if (TREE_CODE (itype) == INTEGER_CST
4373 && TREE_OVERFLOW (itype))
4375 error ("size of array %qs is too large", name);
4376 type = error_mark_node;
4377 continue;
4380 itype = build_index_type (itype);
4383 else if (decl_context == FIELD)
4385 if (pedantic && !flag_isoc99 && !in_system_header)
4386 pedwarn ("ISO C90 does not support flexible array members");
4388 /* ISO C99 Flexible array members are effectively
4389 identical to GCC's zero-length array extension. */
4390 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4392 else if (decl_context == PARM)
4394 if (array_parm_vla_unspec_p)
4396 if (! orig_name)
4398 /* C99 6.7.5.2p4 */
4399 error ("%<[*]%> not allowed in other than a declaration");
4402 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4403 size_varies = 1;
4406 else if (decl_context == TYPENAME)
4408 if (array_parm_vla_unspec_p)
4410 /* The error is printed elsewhere. We use this to
4411 avoid messing up with incomplete array types of
4412 the same type, that would otherwise be modified
4413 below. */
4414 itype = build_range_type (sizetype, size_zero_node,
4415 NULL_TREE);
4419 /* Complain about arrays of incomplete types. */
4420 if (!COMPLETE_TYPE_P (type))
4422 error ("array type has incomplete element type");
4423 type = error_mark_node;
4425 else
4426 /* When itype is NULL, a shared incomplete array type is
4427 returned for all array of a given type. Elsewhere we
4428 make sure we don't complete that type before copying
4429 it, but here we want to make sure we don't ever
4430 modify the shared type, so we gcc_assert (itype)
4431 below. */
4432 type = build_array_type (type, itype);
4434 if (type != error_mark_node)
4436 if (size_varies)
4438 /* It is ok to modify type here even if itype is
4439 NULL: if size_varies, we're in a
4440 multi-dimensional array and the inner type has
4441 variable size, so the enclosing shared array type
4442 must too. */
4443 if (size && TREE_CODE (size) == INTEGER_CST)
4444 type
4445 = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4446 C_TYPE_VARIABLE_SIZE (type) = 1;
4449 /* The GCC extension for zero-length arrays differs from
4450 ISO flexible array members in that sizeof yields
4451 zero. */
4452 if (size && integer_zerop (size))
4454 gcc_assert (itype);
4455 TYPE_SIZE (type) = bitsize_zero_node;
4456 TYPE_SIZE_UNIT (type) = size_zero_node;
4458 if (array_parm_vla_unspec_p)
4460 gcc_assert (itype);
4461 /* The type is complete. C99 6.7.5.2p4 */
4462 TYPE_SIZE (type) = bitsize_zero_node;
4463 TYPE_SIZE_UNIT (type) = size_zero_node;
4467 if (decl_context != PARM
4468 && (array_ptr_quals != TYPE_UNQUALIFIED
4469 || array_ptr_attrs != NULL_TREE
4470 || array_parm_static))
4472 error ("static or type qualifiers in non-parameter array declarator");
4473 array_ptr_quals = TYPE_UNQUALIFIED;
4474 array_ptr_attrs = NULL_TREE;
4475 array_parm_static = 0;
4477 break;
4479 case cdk_function:
4481 /* Say it's a definition only for the declarator closest
4482 to the identifier, apart possibly from some
4483 attributes. */
4484 bool really_funcdef = false;
4485 tree arg_types;
4486 if (funcdef_flag)
4488 const struct c_declarator *t = declarator->declarator;
4489 while (t->kind == cdk_attrs)
4490 t = t->declarator;
4491 really_funcdef = (t->kind == cdk_id);
4494 /* Declaring a function type. Make sure we have a valid
4495 type for the function to return. */
4496 if (type == error_mark_node)
4497 continue;
4499 size_varies = 0;
4501 /* Warn about some types functions can't return. */
4502 if (TREE_CODE (type) == FUNCTION_TYPE)
4504 error ("%qs declared as function returning a function", name);
4505 type = integer_type_node;
4507 if (TREE_CODE (type) == ARRAY_TYPE)
4509 error ("%qs declared as function returning an array", name);
4510 type = integer_type_node;
4513 /* Construct the function type and go to the next
4514 inner layer of declarator. */
4515 arg_info = declarator->u.arg_info;
4516 arg_types = grokparms (arg_info, really_funcdef);
4517 if (really_funcdef)
4518 put_pending_sizes (arg_info->pending_sizes);
4520 /* Type qualifiers before the return type of the function
4521 qualify the return type, not the function type. */
4522 if (type_quals)
4524 /* Type qualifiers on a function return type are
4525 normally permitted by the standard but have no
4526 effect, so give a warning at -Wreturn-type.
4527 Qualifiers on a void return type are banned on
4528 function definitions in ISO C; GCC used to used
4529 them for noreturn functions. */
4530 if (VOID_TYPE_P (type) && really_funcdef)
4531 pedwarn ("function definition has qualified void return type");
4532 else
4533 warning (OPT_Wreturn_type,
4534 "type qualifiers ignored on function return type");
4536 type = c_build_qualified_type (type, type_quals);
4538 type_quals = TYPE_UNQUALIFIED;
4540 type = build_function_type (type, arg_types);
4541 declarator = declarator->declarator;
4543 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4544 the formal parameter list of this FUNCTION_TYPE to point to
4545 the FUNCTION_TYPE node itself. */
4547 tree link;
4549 for (link = arg_info->tags;
4550 link;
4551 link = TREE_CHAIN (link))
4552 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4554 break;
4556 case cdk_pointer:
4558 /* Merge any constancy or volatility into the target type
4559 for the pointer. */
4561 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4562 && type_quals)
4563 pedwarn ("ISO C forbids qualified function types");
4564 if (type_quals)
4565 type = c_build_qualified_type (type, type_quals);
4566 size_varies = 0;
4568 /* When the pointed-to type involves components of variable size,
4569 care must be taken to ensure that the size evaluation code is
4570 emitted early enough to dominate all the possible later uses
4571 and late enough for the variables on which it depends to have
4572 been assigned.
4574 This is expected to happen automatically when the pointed-to
4575 type has a name/declaration of it's own, but special attention
4576 is required if the type is anonymous.
4578 We handle the NORMAL and FIELD contexts here by attaching an
4579 artificial TYPE_DECL to such pointed-to type. This forces the
4580 sizes evaluation at a safe point and ensures it is not deferred
4581 until e.g. within a deeper conditional context.
4583 We expect nothing to be needed here for PARM or TYPENAME.
4584 Pushing a TYPE_DECL at this point for TYPENAME would actually
4585 be incorrect, as we might be in the middle of an expression
4586 with side effects on the pointed-to type size "arguments" prior
4587 to the pointer declaration point and the fake TYPE_DECL in the
4588 enclosing context would force the size evaluation prior to the
4589 side effects. */
4591 if (!TYPE_NAME (type)
4592 && (decl_context == NORMAL || decl_context == FIELD)
4593 && variably_modified_type_p (type, NULL_TREE))
4595 tree decl = build_decl (TYPE_DECL, NULL_TREE, type);
4596 DECL_ARTIFICIAL (decl) = 1;
4597 pushdecl (decl);
4598 finish_decl (decl, NULL_TREE, NULL_TREE);
4599 TYPE_NAME (type) = decl;
4602 type = build_pointer_type (type);
4604 /* Process type qualifiers (such as const or volatile)
4605 that were given inside the `*'. */
4606 type_quals = declarator->u.pointer_quals;
4608 declarator = declarator->declarator;
4609 break;
4611 default:
4612 gcc_unreachable ();
4615 *decl_attrs = chainon (returned_attrs, *decl_attrs);
4617 /* Now TYPE has the actual type, apart from any qualifiers in
4618 TYPE_QUALS. */
4620 /* Check the type and width of a bit-field. */
4621 if (bitfield)
4622 check_bitfield_type_and_width (&type, width, orig_name);
4624 /* Did array size calculations overflow? */
4626 if (TREE_CODE (type) == ARRAY_TYPE
4627 && COMPLETE_TYPE_P (type)
4628 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
4629 && TREE_OVERFLOW (TYPE_SIZE_UNIT (type)))
4631 error ("size of array %qs is too large", name);
4632 /* If we proceed with the array type as it is, we'll eventually
4633 crash in tree_low_cst(). */
4634 type = error_mark_node;
4637 /* If this is declaring a typedef name, return a TYPE_DECL. */
4639 if (storage_class == csc_typedef)
4641 tree decl;
4642 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4643 && type_quals)
4644 pedwarn ("ISO C forbids qualified function types");
4645 if (type_quals)
4646 type = c_build_qualified_type (type, type_quals);
4647 decl = build_decl (TYPE_DECL, declarator->u.id, type);
4648 if (declspecs->explicit_signed_p)
4649 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4650 if (declspecs->inline_p)
4651 pedwarn ("typedef %q+D declared %<inline%>", decl);
4652 return decl;
4655 /* If this is a type name (such as, in a cast or sizeof),
4656 compute the type and return it now. */
4658 if (decl_context == TYPENAME)
4660 /* Note that the grammar rejects storage classes in typenames
4661 and fields. */
4662 gcc_assert (storage_class == csc_none && !threadp
4663 && !declspecs->inline_p);
4664 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4665 && type_quals)
4666 pedwarn ("ISO C forbids const or volatile function types");
4667 if (type_quals)
4668 type = c_build_qualified_type (type, type_quals);
4669 return type;
4672 if (pedantic && decl_context == FIELD
4673 && variably_modified_type_p (type, NULL_TREE))
4675 /* C99 6.7.2.1p8 */
4676 pedwarn ("a member of a structure or union cannot have a variably modified type");
4679 /* Aside from typedefs and type names (handle above),
4680 `void' at top level (not within pointer)
4681 is allowed only in public variables.
4682 We don't complain about parms either, but that is because
4683 a better error message can be made later. */
4685 if (VOID_TYPE_P (type) && decl_context != PARM
4686 && !((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4687 && (storage_class == csc_extern
4688 || (current_scope == file_scope
4689 && !(storage_class == csc_static
4690 || storage_class == csc_register)))))
4692 error ("variable or field %qs declared void", name);
4693 type = integer_type_node;
4696 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4697 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4700 tree decl;
4702 if (decl_context == PARM)
4704 tree type_as_written;
4705 tree promoted_type;
4707 /* A parameter declared as an array of T is really a pointer to T.
4708 One declared as a function is really a pointer to a function. */
4710 if (TREE_CODE (type) == ARRAY_TYPE)
4712 /* Transfer const-ness of array into that of type pointed to. */
4713 type = TREE_TYPE (type);
4714 if (type_quals)
4715 type = c_build_qualified_type (type, type_quals);
4716 type = build_pointer_type (type);
4717 type_quals = array_ptr_quals;
4718 if (type_quals)
4719 type = c_build_qualified_type (type, type_quals);
4721 /* We don't yet implement attributes in this context. */
4722 if (array_ptr_attrs != NULL_TREE)
4723 warning (OPT_Wattributes,
4724 "attributes in parameter array declarator ignored");
4726 size_varies = 0;
4728 else if (TREE_CODE (type) == FUNCTION_TYPE)
4730 if (pedantic && type_quals)
4731 pedwarn ("ISO C forbids qualified function types");
4732 if (type_quals)
4733 type = c_build_qualified_type (type, type_quals);
4734 type = build_pointer_type (type);
4735 type_quals = TYPE_UNQUALIFIED;
4737 else if (type_quals)
4738 type = c_build_qualified_type (type, type_quals);
4740 type_as_written = type;
4742 decl = build_decl (PARM_DECL, declarator->u.id, type);
4743 if (size_varies)
4744 C_DECL_VARIABLE_SIZE (decl) = 1;
4746 /* Compute the type actually passed in the parmlist,
4747 for the case where there is no prototype.
4748 (For example, shorts and chars are passed as ints.)
4749 When there is a prototype, this is overridden later. */
4751 if (type == error_mark_node)
4752 promoted_type = type;
4753 else
4754 promoted_type = c_type_promotes_to (type);
4756 DECL_ARG_TYPE (decl) = promoted_type;
4757 if (declspecs->inline_p)
4758 pedwarn ("parameter %q+D declared %<inline%>", decl);
4760 else if (decl_context == FIELD)
4762 /* Note that the grammar rejects storage classes in typenames
4763 and fields. */
4764 gcc_assert (storage_class == csc_none && !threadp
4765 && !declspecs->inline_p);
4767 /* Structure field. It may not be a function. */
4769 if (TREE_CODE (type) == FUNCTION_TYPE)
4771 error ("field %qs declared as a function", name);
4772 type = build_pointer_type (type);
4774 else if (TREE_CODE (type) != ERROR_MARK
4775 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4777 error ("field %qs has incomplete type", name);
4778 type = error_mark_node;
4780 type = c_build_qualified_type (type, type_quals);
4781 decl = build_decl (FIELD_DECL, declarator->u.id, type);
4782 DECL_NONADDRESSABLE_P (decl) = bitfield;
4783 if (bitfield && !declarator->u.id)
4784 TREE_NO_WARNING (decl) = 1;
4786 if (size_varies)
4787 C_DECL_VARIABLE_SIZE (decl) = 1;
4789 else if (TREE_CODE (type) == FUNCTION_TYPE)
4791 if (storage_class == csc_register || threadp)
4793 error ("invalid storage class for function %qs", name);
4795 else if (current_scope != file_scope)
4797 /* Function declaration not at file scope. Storage
4798 classes other than `extern' are not allowed, C99
4799 6.7.1p5, and `extern' makes no difference. However,
4800 GCC allows 'auto', perhaps with 'inline', to support
4801 nested functions. */
4802 if (storage_class == csc_auto)
4804 if (pedantic)
4805 pedwarn ("invalid storage class for function %qs", name);
4807 else if (storage_class == csc_static)
4809 error ("invalid storage class for function %qs", name);
4810 if (funcdef_flag)
4811 storage_class = declspecs->storage_class = csc_none;
4812 else
4813 return 0;
4817 decl = build_decl (FUNCTION_DECL, declarator->u.id, type);
4818 decl = build_decl_attribute_variant (decl, decl_attr);
4820 if (pedantic && type_quals && !DECL_IN_SYSTEM_HEADER (decl))
4821 pedwarn ("ISO C forbids qualified function types");
4823 /* GNU C interprets a volatile-qualified function type to indicate
4824 that the function does not return. */
4825 if ((type_quals & TYPE_QUAL_VOLATILE)
4826 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4827 warning (0, "%<noreturn%> function returns non-void value");
4829 /* Every function declaration is an external reference
4830 (DECL_EXTERNAL) except for those which are not at file
4831 scope and are explicitly declared "auto". This is
4832 forbidden by standard C (C99 6.7.1p5) and is interpreted by
4833 GCC to signify a forward declaration of a nested function. */
4834 if (storage_class == csc_auto && current_scope != file_scope)
4835 DECL_EXTERNAL (decl) = 0;
4836 /* In C99, a function which is declared 'inline' with 'extern'
4837 is not an external reference (which is confusing). It
4838 means that the later definition of the function must be output
4839 in this file, C99 6.7.4p6. In GNU C89, a function declared
4840 'extern inline' is an external reference. */
4841 else if (declspecs->inline_p && storage_class != csc_static)
4842 DECL_EXTERNAL (decl) = ((storage_class == csc_extern)
4843 == flag_gnu89_inline);
4844 else
4845 DECL_EXTERNAL (decl) = !initialized;
4847 /* Record absence of global scope for `static' or `auto'. */
4848 TREE_PUBLIC (decl)
4849 = !(storage_class == csc_static || storage_class == csc_auto);
4851 /* For a function definition, record the argument information
4852 block where store_parm_decls will look for it. */
4853 if (funcdef_flag)
4854 current_function_arg_info = arg_info;
4856 if (declspecs->default_int_p)
4857 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4859 /* Record presence of `inline', if it is reasonable. */
4860 if (flag_hosted && MAIN_NAME_P (declarator->u.id))
4862 if (declspecs->inline_p)
4863 pedwarn ("cannot inline function %<main%>");
4865 else if (declspecs->inline_p)
4867 /* Record that the function is declared `inline'. */
4868 DECL_DECLARED_INLINE_P (decl) = 1;
4870 /* Do not mark bare declarations as DECL_INLINE. Doing so
4871 in the presence of multiple declarations can result in
4872 the abstract origin pointing between the declarations,
4873 which will confuse dwarf2out. */
4874 if (initialized)
4875 DECL_INLINE (decl) = 1;
4877 /* If -finline-functions, assume it can be inlined. This does
4878 two things: let the function be deferred until it is actually
4879 needed, and let dwarf2 know that the function is inlinable. */
4880 else if (flag_inline_trees == 2 && initialized)
4881 DECL_INLINE (decl) = 1;
4883 else
4885 /* It's a variable. */
4886 /* An uninitialized decl with `extern' is a reference. */
4887 int extern_ref = !initialized && storage_class == csc_extern;
4889 type = c_build_qualified_type (type, type_quals);
4891 /* C99 6.2.2p7: It is invalid (compile-time undefined
4892 behavior) to create an 'extern' declaration for a
4893 variable if there is a global declaration that is
4894 'static' and the global declaration is not visible.
4895 (If the static declaration _is_ currently visible,
4896 the 'extern' declaration is taken to refer to that decl.) */
4897 if (extern_ref && current_scope != file_scope)
4899 tree global_decl = identifier_global_value (declarator->u.id);
4900 tree visible_decl = lookup_name (declarator->u.id);
4902 if (global_decl
4903 && global_decl != visible_decl
4904 && TREE_CODE (global_decl) == VAR_DECL
4905 && !TREE_PUBLIC (global_decl))
4906 error ("variable previously declared %<static%> redeclared "
4907 "%<extern%>");
4910 decl = build_decl (VAR_DECL, declarator->u.id, type);
4911 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4912 if (size_varies)
4913 C_DECL_VARIABLE_SIZE (decl) = 1;
4915 if (declspecs->inline_p)
4916 pedwarn ("variable %q+D declared %<inline%>", decl);
4918 /* At file scope, an initialized extern declaration may follow
4919 a static declaration. In that case, DECL_EXTERNAL will be
4920 reset later in start_decl. */
4921 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4923 /* At file scope, the presence of a `static' or `register' storage
4924 class specifier, or the absence of all storage class specifiers
4925 makes this declaration a definition (perhaps tentative). Also,
4926 the absence of `static' makes it public. */
4927 if (current_scope == file_scope)
4929 TREE_PUBLIC (decl) = storage_class != csc_static;
4930 TREE_STATIC (decl) = !extern_ref;
4932 /* Not at file scope, only `static' makes a static definition. */
4933 else
4935 TREE_STATIC (decl) = (storage_class == csc_static);
4936 TREE_PUBLIC (decl) = extern_ref;
4939 if (threadp)
4940 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
4943 if (storage_class == csc_extern
4944 && variably_modified_type_p (type, NULL_TREE))
4946 /* C99 6.7.5.2p2 */
4947 error ("object with variably modified type must have no linkage");
4950 /* Record `register' declaration for warnings on &
4951 and in case doing stupid register allocation. */
4953 if (storage_class == csc_register)
4955 C_DECL_REGISTER (decl) = 1;
4956 DECL_REGISTER (decl) = 1;
4959 /* Record constancy and volatility. */
4960 c_apply_type_quals_to_decl (type_quals, decl);
4962 /* If a type has volatile components, it should be stored in memory.
4963 Otherwise, the fact that those components are volatile
4964 will be ignored, and would even crash the compiler.
4965 Of course, this only makes sense on VAR,PARM, and RESULT decl's. */
4966 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl))
4967 && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
4968 || TREE_CODE (decl) == RESULT_DECL))
4970 /* It is not an error for a structure with volatile fields to
4971 be declared register, but reset DECL_REGISTER since it
4972 cannot actually go in a register. */
4973 int was_reg = C_DECL_REGISTER (decl);
4974 C_DECL_REGISTER (decl) = 0;
4975 DECL_REGISTER (decl) = 0;
4976 c_mark_addressable (decl);
4977 C_DECL_REGISTER (decl) = was_reg;
4980 /* This is the earliest point at which we might know the assembler
4981 name of a variable. Thus, if it's known before this, die horribly. */
4982 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl));
4984 return decl;
4988 /* Decode the parameter-list info for a function type or function definition.
4989 The argument is the value returned by `get_parm_info' (or made in c-parse.c
4990 if there is an identifier list instead of a parameter decl list).
4991 These two functions are separate because when a function returns
4992 or receives functions then each is called multiple times but the order
4993 of calls is different. The last call to `grokparms' is always the one
4994 that contains the formal parameter names of a function definition.
4996 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4998 FUNCDEF_FLAG is true for a function definition, false for
4999 a mere declaration. A nonempty identifier-list gets an error message
5000 when FUNCDEF_FLAG is false. */
5002 static tree
5003 grokparms (struct c_arg_info *arg_info, bool funcdef_flag)
5005 tree arg_types = arg_info->types;
5007 if (funcdef_flag && arg_info->had_vla_unspec)
5009 /* A function definition isn't function prototype scope C99 6.2.1p4. */
5010 /* C99 6.7.5.2p4 */
5011 error ("%<[*]%> not allowed in other than function prototype scope");
5014 if (arg_types == 0 && !funcdef_flag && !in_system_header)
5015 warning (OPT_Wstrict_prototypes,
5016 "function declaration isn%'t a prototype");
5018 if (arg_types == error_mark_node)
5019 return 0; /* don't set TYPE_ARG_TYPES in this case */
5021 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
5023 if (!funcdef_flag)
5024 pedwarn ("parameter names (without types) in function declaration");
5026 arg_info->parms = arg_info->types;
5027 arg_info->types = 0;
5028 return 0;
5030 else
5032 tree parm, type, typelt;
5033 unsigned int parmno;
5035 /* If there is a parameter of incomplete type in a definition,
5036 this is an error. In a declaration this is valid, and a
5037 struct or union type may be completed later, before any calls
5038 or definition of the function. In the case where the tag was
5039 first declared within the parameter list, a warning has
5040 already been given. If a parameter has void type, then
5041 however the function cannot be defined or called, so
5042 warn. */
5044 for (parm = arg_info->parms, typelt = arg_types, parmno = 1;
5045 parm;
5046 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
5048 type = TREE_VALUE (typelt);
5049 if (type == error_mark_node)
5050 continue;
5052 if (!COMPLETE_TYPE_P (type))
5054 if (funcdef_flag)
5056 if (DECL_NAME (parm))
5057 error ("parameter %u (%q+D) has incomplete type",
5058 parmno, parm);
5059 else
5060 error ("%Jparameter %u has incomplete type",
5061 parm, parmno);
5063 TREE_VALUE (typelt) = error_mark_node;
5064 TREE_TYPE (parm) = error_mark_node;
5066 else if (VOID_TYPE_P (type))
5068 if (DECL_NAME (parm))
5069 warning (0, "parameter %u (%q+D) has void type",
5070 parmno, parm);
5071 else
5072 warning (0, "%Jparameter %u has void type",
5073 parm, parmno);
5077 if (DECL_NAME (parm) && TREE_USED (parm))
5078 warn_if_shadowing (parm);
5080 return arg_types;
5084 /* Take apart the current scope and return a c_arg_info structure with
5085 info on a parameter list just parsed.
5087 This structure is later fed to 'grokparms' and 'store_parm_decls'.
5089 ELLIPSIS being true means the argument list ended in '...' so don't
5090 append a sentinel (void_list_node) to the end of the type-list. */
5092 struct c_arg_info *
5093 get_parm_info (bool ellipsis)
5095 struct c_binding *b = current_scope->bindings;
5096 struct c_arg_info *arg_info = XOBNEW (&parser_obstack,
5097 struct c_arg_info);
5098 tree parms = 0;
5099 tree tags = 0;
5100 tree types = 0;
5101 tree others = 0;
5103 static bool explained_incomplete_types = false;
5104 bool gave_void_only_once_err = false;
5106 arg_info->parms = 0;
5107 arg_info->tags = 0;
5108 arg_info->types = 0;
5109 arg_info->others = 0;
5110 arg_info->pending_sizes = 0;
5111 arg_info->had_vla_unspec = current_scope->had_vla_unspec;
5113 /* The bindings in this scope must not get put into a block.
5114 We will take care of deleting the binding nodes. */
5115 current_scope->bindings = 0;
5117 /* This function is only called if there was *something* on the
5118 parameter list. */
5119 gcc_assert (b);
5121 /* A parameter list consisting solely of 'void' indicates that the
5122 function takes no arguments. But if the 'void' is qualified
5123 (by 'const' or 'volatile'), or has a storage class specifier
5124 ('register'), then the behavior is undefined; issue an error.
5125 Typedefs for 'void' are OK (see DR#157). */
5126 if (b->prev == 0 /* one binding */
5127 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
5128 && !DECL_NAME (b->decl) /* anonymous */
5129 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
5131 if (TREE_THIS_VOLATILE (b->decl)
5132 || TREE_READONLY (b->decl)
5133 || C_DECL_REGISTER (b->decl))
5134 error ("%<void%> as only parameter may not be qualified");
5136 /* There cannot be an ellipsis. */
5137 if (ellipsis)
5138 error ("%<void%> must be the only parameter");
5140 arg_info->types = void_list_node;
5141 return arg_info;
5144 if (!ellipsis)
5145 types = void_list_node;
5147 /* Break up the bindings list into parms, tags, types, and others;
5148 apply sanity checks; purge the name-to-decl bindings. */
5149 while (b)
5151 tree decl = b->decl;
5152 tree type = TREE_TYPE (decl);
5153 const char *keyword;
5155 switch (TREE_CODE (decl))
5157 case PARM_DECL:
5158 if (b->id)
5160 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5161 I_SYMBOL_BINDING (b->id) = b->shadowed;
5164 /* Check for forward decls that never got their actual decl. */
5165 if (TREE_ASM_WRITTEN (decl))
5166 error ("parameter %q+D has just a forward declaration", decl);
5167 /* Check for (..., void, ...) and issue an error. */
5168 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
5170 if (!gave_void_only_once_err)
5172 error ("%<void%> must be the only parameter");
5173 gave_void_only_once_err = true;
5176 else
5178 /* Valid parameter, add it to the list. */
5179 TREE_CHAIN (decl) = parms;
5180 parms = decl;
5182 /* Since there is a prototype, args are passed in their
5183 declared types. The back end may override this later. */
5184 DECL_ARG_TYPE (decl) = type;
5185 types = tree_cons (0, type, types);
5187 break;
5189 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
5190 case UNION_TYPE: keyword = "union"; goto tag;
5191 case RECORD_TYPE: keyword = "struct"; goto tag;
5192 tag:
5193 /* Types may not have tag-names, in which case the type
5194 appears in the bindings list with b->id NULL. */
5195 if (b->id)
5197 gcc_assert (I_TAG_BINDING (b->id) == b);
5198 I_TAG_BINDING (b->id) = b->shadowed;
5201 /* Warn about any struct, union or enum tags defined in a
5202 parameter list. The scope of such types is limited to
5203 the parameter list, which is rarely if ever desirable
5204 (it's impossible to call such a function with type-
5205 correct arguments). An anonymous union parm type is
5206 meaningful as a GNU extension, so don't warn for that. */
5207 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
5209 if (b->id)
5210 /* The %s will be one of 'struct', 'union', or 'enum'. */
5211 warning (0, "%<%s %E%> declared inside parameter list",
5212 keyword, b->id);
5213 else
5214 /* The %s will be one of 'struct', 'union', or 'enum'. */
5215 warning (0, "anonymous %s declared inside parameter list",
5216 keyword);
5218 if (!explained_incomplete_types)
5220 warning (0, "its scope is only this definition or declaration,"
5221 " which is probably not what you want");
5222 explained_incomplete_types = true;
5226 tags = tree_cons (b->id, decl, tags);
5227 break;
5229 case CONST_DECL:
5230 case TYPE_DECL:
5231 case FUNCTION_DECL:
5232 /* CONST_DECLs appear here when we have an embedded enum,
5233 and TYPE_DECLs appear here when we have an embedded struct
5234 or union. No warnings for this - we already warned about the
5235 type itself. FUNCTION_DECLs appear when there is an implicit
5236 function declaration in the parameter list. */
5238 TREE_CHAIN (decl) = others;
5239 others = decl;
5240 /* fall through */
5242 case ERROR_MARK:
5243 /* error_mark_node appears here when we have an undeclared
5244 variable. Just throw it away. */
5245 if (b->id)
5247 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5248 I_SYMBOL_BINDING (b->id) = b->shadowed;
5250 break;
5252 /* Other things that might be encountered. */
5253 case LABEL_DECL:
5254 case VAR_DECL:
5255 default:
5256 gcc_unreachable ();
5259 b = free_binding_and_advance (b);
5262 arg_info->parms = parms;
5263 arg_info->tags = tags;
5264 arg_info->types = types;
5265 arg_info->others = others;
5266 arg_info->pending_sizes = get_pending_sizes ();
5267 return arg_info;
5270 /* Get the struct, enum or union (CODE says which) with tag NAME.
5271 Define the tag as a forward-reference if it is not defined.
5272 Return a c_typespec structure for the type specifier. */
5274 struct c_typespec
5275 parser_xref_tag (enum tree_code code, tree name)
5277 struct c_typespec ret;
5278 /* If a cross reference is requested, look up the type
5279 already defined for this tag and return it. */
5281 tree ref = lookup_tag (code, name, 0);
5282 /* If this is the right type of tag, return what we found.
5283 (This reference will be shadowed by shadow_tag later if appropriate.)
5284 If this is the wrong type of tag, do not return it. If it was the
5285 wrong type in the same scope, we will have had an error
5286 message already; if in a different scope and declaring
5287 a name, pending_xref_error will give an error message; but if in a
5288 different scope and not declaring a name, this tag should
5289 shadow the previous declaration of a different type of tag, and
5290 this would not work properly if we return the reference found.
5291 (For example, with "struct foo" in an outer scope, "union foo;"
5292 must shadow that tag with a new one of union type.) */
5293 ret.kind = (ref ? ctsk_tagref : ctsk_tagfirstref);
5294 if (ref && TREE_CODE (ref) == code)
5296 ret.spec = ref;
5297 return ret;
5300 /* If no such tag is yet defined, create a forward-reference node
5301 and record it as the "definition".
5302 When a real declaration of this type is found,
5303 the forward-reference will be altered into a real type. */
5305 ref = make_node (code);
5306 if (code == ENUMERAL_TYPE)
5308 /* Give the type a default layout like unsigned int
5309 to avoid crashing if it does not get defined. */
5310 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5311 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5312 TYPE_USER_ALIGN (ref) = 0;
5313 TYPE_UNSIGNED (ref) = 1;
5314 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5315 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5316 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5319 pushtag (name, ref);
5321 ret.spec = ref;
5322 return ret;
5325 /* Get the struct, enum or union (CODE says which) with tag NAME.
5326 Define the tag as a forward-reference if it is not defined.
5327 Return a tree for the type. */
5329 tree
5330 xref_tag (enum tree_code code, tree name)
5332 return parser_xref_tag (code, name).spec;
5335 /* Make sure that the tag NAME is defined *in the current scope*
5336 at least as a forward reference.
5337 CODE says which kind of tag NAME ought to be. */
5339 tree
5340 start_struct (enum tree_code code, tree name)
5342 /* If there is already a tag defined at this scope
5343 (as a forward reference), just return it. */
5345 tree ref = 0;
5347 if (name != 0)
5348 ref = lookup_tag (code, name, 1);
5349 if (ref && TREE_CODE (ref) == code)
5351 if (TYPE_SIZE (ref))
5353 if (code == UNION_TYPE)
5354 error ("redefinition of %<union %E%>", name);
5355 else
5356 error ("redefinition of %<struct %E%>", name);
5358 else if (C_TYPE_BEING_DEFINED (ref))
5360 if (code == UNION_TYPE)
5361 error ("nested redefinition of %<union %E%>", name);
5362 else
5363 error ("nested redefinition of %<struct %E%>", name);
5364 /* Don't create structures that contain themselves. */
5365 ref = NULL_TREE;
5369 /* Otherwise create a forward-reference just so the tag is in scope. */
5371 if (ref == NULL_TREE || TREE_CODE (ref) != code)
5373 ref = make_node (code);
5374 pushtag (name, ref);
5377 C_TYPE_BEING_DEFINED (ref) = 1;
5378 TYPE_PACKED (ref) = flag_pack_struct;
5379 return ref;
5382 /* Process the specs, declarator and width (NULL if omitted)
5383 of a structure component, returning a FIELD_DECL node.
5384 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
5385 DECL_ATTRS is as for grokdeclarator.
5387 This is done during the parsing of the struct declaration.
5388 The FIELD_DECL nodes are chained together and the lot of them
5389 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5391 tree
5392 grokfield (struct c_declarator *declarator, struct c_declspecs *declspecs,
5393 tree width, tree *decl_attrs)
5395 tree value;
5397 if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE
5398 && width == NULL_TREE)
5400 /* This is an unnamed decl.
5402 If we have something of the form "union { list } ;" then this
5403 is the anonymous union extension. Similarly for struct.
5405 If this is something of the form "struct foo;", then
5406 If MS extensions are enabled, this is handled as an
5407 anonymous struct.
5408 Otherwise this is a forward declaration of a structure tag.
5410 If this is something of the form "foo;" and foo is a TYPE_DECL, then
5411 If MS extensions are enabled and foo names a structure, then
5412 again this is an anonymous struct.
5413 Otherwise this is an error.
5415 Oh what a horrid tangled web we weave. I wonder if MS consciously
5416 took this from Plan 9 or if it was an accident of implementation
5417 that took root before someone noticed the bug... */
5419 tree type = declspecs->type;
5420 bool type_ok = (TREE_CODE (type) == RECORD_TYPE
5421 || TREE_CODE (type) == UNION_TYPE);
5422 bool ok = false;
5424 if (type_ok
5425 && (flag_ms_extensions || !declspecs->typedef_p))
5427 if (flag_ms_extensions)
5428 ok = true;
5429 else if (flag_iso)
5430 ok = false;
5431 else if (TYPE_NAME (type) == NULL)
5432 ok = true;
5433 else
5434 ok = false;
5436 if (!ok)
5438 pedwarn ("declaration does not declare anything");
5439 return NULL_TREE;
5441 if (pedantic)
5442 pedwarn ("ISO C doesn%'t support unnamed structs/unions");
5445 value = grokdeclarator (declarator, declspecs, FIELD, false,
5446 width ? &width : NULL, decl_attrs,
5447 DEPRECATED_NORMAL);
5449 finish_decl (value, NULL_TREE, NULL_TREE);
5450 DECL_INITIAL (value) = width;
5452 return value;
5455 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5456 the list such that this does not present a problem later. */
5458 static void
5459 detect_field_duplicates (tree fieldlist)
5461 tree x, y;
5462 int timeout = 10;
5464 /* First, see if there are more than "a few" fields.
5465 This is trivially true if there are zero or one fields. */
5466 if (!fieldlist)
5467 return;
5468 x = TREE_CHAIN (fieldlist);
5469 if (!x)
5470 return;
5471 do {
5472 timeout--;
5473 x = TREE_CHAIN (x);
5474 } while (timeout > 0 && x);
5476 /* If there were "few" fields, avoid the overhead of allocating
5477 a hash table. Instead just do the nested traversal thing. */
5478 if (timeout > 0)
5480 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5481 if (DECL_NAME (x))
5483 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5484 if (DECL_NAME (y) == DECL_NAME (x))
5486 error ("duplicate member %q+D", x);
5487 DECL_NAME (x) = NULL_TREE;
5491 else
5493 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5494 void **slot;
5496 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5497 if ((y = DECL_NAME (x)) != 0)
5499 slot = htab_find_slot (htab, y, INSERT);
5500 if (*slot)
5502 error ("duplicate member %q+D", x);
5503 DECL_NAME (x) = NULL_TREE;
5505 *slot = y;
5508 htab_delete (htab);
5512 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5513 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5514 ATTRIBUTES are attributes to be applied to the structure. */
5516 tree
5517 finish_struct (tree t, tree fieldlist, tree attributes)
5519 tree x;
5520 bool toplevel = file_scope == current_scope;
5521 int saw_named_field;
5523 /* If this type was previously laid out as a forward reference,
5524 make sure we lay it out again. */
5526 TYPE_SIZE (t) = 0;
5528 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5530 if (pedantic)
5532 for (x = fieldlist; x; x = TREE_CHAIN (x))
5533 if (DECL_NAME (x) != 0)
5534 break;
5536 if (x == 0)
5538 if (TREE_CODE (t) == UNION_TYPE)
5540 if (fieldlist)
5541 pedwarn ("union has no named members");
5542 else
5543 pedwarn ("union has no members");
5545 else
5547 if (fieldlist)
5548 pedwarn ("struct has no named members");
5549 else
5550 pedwarn ("struct has no members");
5555 /* Install struct as DECL_CONTEXT of each field decl.
5556 Also process specified field sizes, found in the DECL_INITIAL,
5557 storing 0 there after the type has been changed to precision equal
5558 to its width, rather than the precision of the specified standard
5559 type. (Correct layout requires the original type to have been preserved
5560 until now.) */
5562 saw_named_field = 0;
5563 for (x = fieldlist; x; x = TREE_CHAIN (x))
5565 if (TREE_TYPE (x) == error_mark_node)
5566 continue;
5568 DECL_CONTEXT (x) = t;
5570 if (TYPE_PACKED (t) && TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
5571 DECL_PACKED (x) = 1;
5573 /* If any field is const, the structure type is pseudo-const. */
5574 if (TREE_READONLY (x))
5575 C_TYPE_FIELDS_READONLY (t) = 1;
5576 else
5578 /* A field that is pseudo-const makes the structure likewise. */
5579 tree t1 = TREE_TYPE (x);
5580 while (TREE_CODE (t1) == ARRAY_TYPE)
5581 t1 = TREE_TYPE (t1);
5582 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5583 && C_TYPE_FIELDS_READONLY (t1))
5584 C_TYPE_FIELDS_READONLY (t) = 1;
5587 /* Any field that is volatile means variables of this type must be
5588 treated in some ways as volatile. */
5589 if (TREE_THIS_VOLATILE (x))
5590 C_TYPE_FIELDS_VOLATILE (t) = 1;
5592 /* Any field of nominal variable size implies structure is too. */
5593 if (C_DECL_VARIABLE_SIZE (x))
5594 C_TYPE_VARIABLE_SIZE (t) = 1;
5596 if (DECL_INITIAL (x))
5598 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5599 DECL_SIZE (x) = bitsize_int (width);
5600 DECL_BIT_FIELD (x) = 1;
5601 SET_DECL_C_BIT_FIELD (x);
5604 /* Detect flexible array member in an invalid context. */
5605 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5606 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5607 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5608 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5610 if (TREE_CODE (t) == UNION_TYPE)
5612 error ("%Jflexible array member in union", x);
5613 TREE_TYPE (x) = error_mark_node;
5615 else if (TREE_CHAIN (x) != NULL_TREE)
5617 error ("%Jflexible array member not at end of struct", x);
5618 TREE_TYPE (x) = error_mark_node;
5620 else if (!saw_named_field)
5622 error ("%Jflexible array member in otherwise empty struct", x);
5623 TREE_TYPE (x) = error_mark_node;
5627 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5628 && flexible_array_type_p (TREE_TYPE (x)))
5629 pedwarn ("%Jinvalid use of structure with flexible array member", x);
5631 if (DECL_NAME (x))
5632 saw_named_field = 1;
5635 detect_field_duplicates (fieldlist);
5637 /* Now we have the nearly final fieldlist. Record it,
5638 then lay out the structure or union (including the fields). */
5640 TYPE_FIELDS (t) = fieldlist;
5642 layout_type (t);
5644 /* Give bit-fields their proper types. */
5646 tree *fieldlistp = &fieldlist;
5647 while (*fieldlistp)
5648 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp)
5649 && TREE_TYPE (*fieldlistp) != error_mark_node)
5651 unsigned HOST_WIDE_INT width
5652 = tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
5653 tree type = TREE_TYPE (*fieldlistp);
5654 if (width != TYPE_PRECISION (type))
5656 TREE_TYPE (*fieldlistp)
5657 = c_build_bitfield_integer_type (width, TYPE_UNSIGNED (type));
5658 DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
5660 DECL_INITIAL (*fieldlistp) = 0;
5662 else
5663 fieldlistp = &TREE_CHAIN (*fieldlistp);
5666 /* Now we have the truly final field list.
5667 Store it in this type and in the variants. */
5669 TYPE_FIELDS (t) = fieldlist;
5671 /* If there are lots of fields, sort so we can look through them fast.
5672 We arbitrarily consider 16 or more elts to be "a lot". */
5675 int len = 0;
5677 for (x = fieldlist; x; x = TREE_CHAIN (x))
5679 if (len > 15 || DECL_NAME (x) == NULL)
5680 break;
5681 len += 1;
5684 if (len > 15)
5686 tree *field_array;
5687 struct lang_type *space;
5688 struct sorted_fields_type *space2;
5690 len += list_length (x);
5692 /* Use the same allocation policy here that make_node uses, to
5693 ensure that this lives as long as the rest of the struct decl.
5694 All decls in an inline function need to be saved. */
5696 space = GGC_CNEW (struct lang_type);
5697 space2 = GGC_NEWVAR (struct sorted_fields_type,
5698 sizeof (struct sorted_fields_type) + len * sizeof (tree));
5700 len = 0;
5701 space->s = space2;
5702 field_array = &space2->elts[0];
5703 for (x = fieldlist; x; x = TREE_CHAIN (x))
5705 field_array[len++] = x;
5707 /* If there is anonymous struct or union, break out of the loop. */
5708 if (DECL_NAME (x) == NULL)
5709 break;
5711 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5712 if (x == NULL)
5714 TYPE_LANG_SPECIFIC (t) = space;
5715 TYPE_LANG_SPECIFIC (t)->s->len = len;
5716 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5717 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5722 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5724 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5725 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5726 C_TYPE_FIELDS_READONLY (x) = C_TYPE_FIELDS_READONLY (t);
5727 C_TYPE_FIELDS_VOLATILE (x) = C_TYPE_FIELDS_VOLATILE (t);
5728 C_TYPE_VARIABLE_SIZE (x) = C_TYPE_VARIABLE_SIZE (t);
5731 /* If this was supposed to be a transparent union, but we can't
5732 make it one, warn and turn off the flag. */
5733 if (TREE_CODE (t) == UNION_TYPE
5734 && TYPE_TRANSPARENT_UNION (t)
5735 && (!TYPE_FIELDS (t) || TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t))))
5737 TYPE_TRANSPARENT_UNION (t) = 0;
5738 warning (0, "union cannot be made transparent");
5741 /* If this structure or union completes the type of any previous
5742 variable declaration, lay it out and output its rtl. */
5743 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5745 x = TREE_CHAIN (x))
5747 tree decl = TREE_VALUE (x);
5748 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5749 layout_array_type (TREE_TYPE (decl));
5750 if (TREE_CODE (decl) != TYPE_DECL)
5752 layout_decl (decl, 0);
5753 if (c_dialect_objc ())
5754 objc_check_decl (decl);
5755 rest_of_decl_compilation (decl, toplevel, 0);
5756 if (!toplevel)
5757 expand_decl (decl);
5760 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5762 /* Finish debugging output for this type. */
5763 rest_of_type_compilation (t, toplevel);
5765 /* If we're inside a function proper, i.e. not file-scope and not still
5766 parsing parameters, then arrange for the size of a variable sized type
5767 to be bound now. */
5768 if (cur_stmt_list && variably_modified_type_p (t, NULL_TREE))
5769 add_stmt (build_stmt (DECL_EXPR, build_decl (TYPE_DECL, NULL, t)));
5771 return t;
5774 /* Lay out the type T, and its element type, and so on. */
5776 static void
5777 layout_array_type (tree t)
5779 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5780 layout_array_type (TREE_TYPE (t));
5781 layout_type (t);
5784 /* Begin compiling the definition of an enumeration type.
5785 NAME is its name (or null if anonymous).
5786 Returns the type object, as yet incomplete.
5787 Also records info about it so that build_enumerator
5788 may be used to declare the individual values as they are read. */
5790 tree
5791 start_enum (struct c_enum_contents *the_enum, tree name)
5793 tree enumtype = 0;
5795 /* If this is the real definition for a previous forward reference,
5796 fill in the contents in the same object that used to be the
5797 forward reference. */
5799 if (name != 0)
5800 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5802 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5804 enumtype = make_node (ENUMERAL_TYPE);
5805 pushtag (name, enumtype);
5808 if (C_TYPE_BEING_DEFINED (enumtype))
5809 error ("nested redefinition of %<enum %E%>", name);
5811 C_TYPE_BEING_DEFINED (enumtype) = 1;
5813 if (TYPE_VALUES (enumtype) != 0)
5815 /* This enum is a named one that has been declared already. */
5816 error ("redeclaration of %<enum %E%>", name);
5818 /* Completely replace its old definition.
5819 The old enumerators remain defined, however. */
5820 TYPE_VALUES (enumtype) = 0;
5823 the_enum->enum_next_value = integer_zero_node;
5824 the_enum->enum_overflow = 0;
5826 if (flag_short_enums)
5827 TYPE_PACKED (enumtype) = 1;
5829 return enumtype;
5832 /* After processing and defining all the values of an enumeration type,
5833 install their decls in the enumeration type and finish it off.
5834 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5835 and ATTRIBUTES are the specified attributes.
5836 Returns ENUMTYPE. */
5838 tree
5839 finish_enum (tree enumtype, tree values, tree attributes)
5841 tree pair, tem;
5842 tree minnode = 0, maxnode = 0;
5843 int precision, unsign;
5844 bool toplevel = (file_scope == current_scope);
5845 struct lang_type *lt;
5847 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5849 /* Calculate the maximum value of any enumerator in this type. */
5851 if (values == error_mark_node)
5852 minnode = maxnode = integer_zero_node;
5853 else
5855 minnode = maxnode = TREE_VALUE (values);
5856 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5858 tree value = TREE_VALUE (pair);
5859 if (tree_int_cst_lt (maxnode, value))
5860 maxnode = value;
5861 if (tree_int_cst_lt (value, minnode))
5862 minnode = value;
5866 /* Construct the final type of this enumeration. It is the same
5867 as one of the integral types - the narrowest one that fits, except
5868 that normally we only go as narrow as int - and signed iff any of
5869 the values are negative. */
5870 unsign = (tree_int_cst_sgn (minnode) >= 0);
5871 precision = MAX (min_precision (minnode, unsign),
5872 min_precision (maxnode, unsign));
5874 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5876 tem = c_common_type_for_size (precision, unsign);
5877 if (tem == NULL)
5879 warning (0, "enumeration values exceed range of largest integer");
5880 tem = long_long_integer_type_node;
5883 else
5884 tem = unsign ? unsigned_type_node : integer_type_node;
5886 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5887 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5888 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5889 TYPE_SIZE (enumtype) = 0;
5891 /* If the precision of the type was specific with an attribute and it
5892 was too small, give an error. Otherwise, use it. */
5893 if (TYPE_PRECISION (enumtype))
5895 if (precision > TYPE_PRECISION (enumtype))
5896 error ("specified mode too small for enumeral values");
5898 else
5899 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5901 layout_type (enumtype);
5903 if (values != error_mark_node)
5905 /* Change the type of the enumerators to be the enum type. We
5906 need to do this irrespective of the size of the enum, for
5907 proper type checking. Replace the DECL_INITIALs of the
5908 enumerators, and the value slots of the list, with copies
5909 that have the enum type; they cannot be modified in place
5910 because they may be shared (e.g. integer_zero_node) Finally,
5911 change the purpose slots to point to the names of the decls. */
5912 for (pair = values; pair; pair = TREE_CHAIN (pair))
5914 tree enu = TREE_PURPOSE (pair);
5915 tree ini = DECL_INITIAL (enu);
5917 TREE_TYPE (enu) = enumtype;
5919 /* The ISO C Standard mandates enumerators to have type int,
5920 even though the underlying type of an enum type is
5921 unspecified. Here we convert any enumerators that fit in
5922 an int to type int, to avoid promotions to unsigned types
5923 when comparing integers with enumerators that fit in the
5924 int range. When -pedantic is given, build_enumerator()
5925 would have already taken care of those that don't fit. */
5926 if (int_fits_type_p (ini, integer_type_node))
5927 tem = integer_type_node;
5928 else
5929 tem = enumtype;
5930 ini = convert (tem, ini);
5932 DECL_INITIAL (enu) = ini;
5933 TREE_PURPOSE (pair) = DECL_NAME (enu);
5934 TREE_VALUE (pair) = ini;
5937 TYPE_VALUES (enumtype) = values;
5940 /* Record the min/max values so that we can warn about bit-field
5941 enumerations that are too small for the values. */
5942 lt = GGC_CNEW (struct lang_type);
5943 lt->enum_min = minnode;
5944 lt->enum_max = maxnode;
5945 TYPE_LANG_SPECIFIC (enumtype) = lt;
5947 /* Fix up all variant types of this enum type. */
5948 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5950 if (tem == enumtype)
5951 continue;
5952 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5953 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5954 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5955 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5956 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5957 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5958 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5959 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5960 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5961 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5962 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5965 /* Finish debugging output for this type. */
5966 rest_of_type_compilation (enumtype, toplevel);
5968 return enumtype;
5971 /* Build and install a CONST_DECL for one value of the
5972 current enumeration type (one that was begun with start_enum).
5973 Return a tree-list containing the CONST_DECL and its value.
5974 Assignment of sequential values by default is handled here. */
5976 tree
5977 build_enumerator (struct c_enum_contents *the_enum, tree name, tree value)
5979 tree decl, type;
5981 /* Validate and default VALUE. */
5983 if (value != 0)
5985 /* Don't issue more errors for error_mark_node (i.e. an
5986 undeclared identifier) - just ignore the value expression. */
5987 if (value == error_mark_node)
5988 value = 0;
5989 else if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
5990 || TREE_CODE (value) != INTEGER_CST)
5992 error ("enumerator value for %qE is not an integer constant", name);
5993 value = 0;
5995 else
5997 value = default_conversion (value);
5998 constant_expression_warning (value);
6002 /* Default based on previous value. */
6003 /* It should no longer be possible to have NON_LVALUE_EXPR
6004 in the default. */
6005 if (value == 0)
6007 value = the_enum->enum_next_value;
6008 if (the_enum->enum_overflow)
6009 error ("overflow in enumeration values");
6012 if (pedantic && !int_fits_type_p (value, integer_type_node))
6014 pedwarn ("ISO C restricts enumerator values to range of %<int%>");
6015 /* XXX This causes -pedantic to change the meaning of the program.
6016 Remove? -zw 2004-03-15 */
6017 value = convert (integer_type_node, value);
6020 /* Set basis for default for next value. */
6021 the_enum->enum_next_value = build_binary_op (PLUS_EXPR, value,
6022 integer_one_node, 0);
6023 the_enum->enum_overflow = tree_int_cst_lt (the_enum->enum_next_value, value);
6025 /* Now create a declaration for the enum value name. */
6027 type = TREE_TYPE (value);
6028 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
6029 TYPE_PRECISION (integer_type_node)),
6030 (TYPE_PRECISION (type)
6031 >= TYPE_PRECISION (integer_type_node)
6032 && TYPE_UNSIGNED (type)));
6034 decl = build_decl (CONST_DECL, name, type);
6035 DECL_INITIAL (decl) = convert (type, value);
6036 pushdecl (decl);
6038 return tree_cons (decl, value, NULL_TREE);
6042 /* Create the FUNCTION_DECL for a function definition.
6043 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
6044 the declaration; they describe the function's name and the type it returns,
6045 but twisted together in a fashion that parallels the syntax of C.
6047 This function creates a binding context for the function body
6048 as well as setting up the FUNCTION_DECL in current_function_decl.
6050 Returns 1 on success. If the DECLARATOR is not suitable for a function
6051 (it defines a datum instead), we return 0, which tells
6052 yyparse to report a parse error. */
6055 start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
6056 tree attributes)
6058 tree decl1, old_decl;
6059 tree restype, resdecl;
6060 struct c_label_context_se *nstack_se;
6061 struct c_label_context_vm *nstack_vm;
6063 current_function_returns_value = 0; /* Assume, until we see it does. */
6064 current_function_returns_null = 0;
6065 current_function_returns_abnormally = 0;
6066 warn_about_return_type = 0;
6067 c_switch_stack = NULL;
6069 nstack_se = XOBNEW (&parser_obstack, struct c_label_context_se);
6070 nstack_se->labels_def = NULL;
6071 nstack_se->labels_used = NULL;
6072 nstack_se->next = label_context_stack_se;
6073 label_context_stack_se = nstack_se;
6075 nstack_vm = XOBNEW (&parser_obstack, struct c_label_context_vm);
6076 nstack_vm->labels_def = NULL;
6077 nstack_vm->labels_used = NULL;
6078 nstack_vm->scope = 0;
6079 nstack_vm->next = label_context_stack_vm;
6080 label_context_stack_vm = nstack_vm;
6082 /* Indicate no valid break/continue context by setting these variables
6083 to some non-null, non-label value. We'll notice and emit the proper
6084 error message in c_finish_bc_stmt. */
6085 c_break_label = c_cont_label = size_zero_node;
6087 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, true, NULL,
6088 &attributes, DEPRECATED_NORMAL);
6090 /* If the declarator is not suitable for a function definition,
6091 cause a syntax error. */
6092 if (decl1 == 0)
6094 label_context_stack_se = label_context_stack_se->next;
6095 label_context_stack_vm = label_context_stack_vm->next;
6096 return 0;
6099 decl_attributes (&decl1, attributes, 0);
6101 if (DECL_DECLARED_INLINE_P (decl1)
6102 && DECL_UNINLINABLE (decl1)
6103 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6104 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
6105 decl1);
6107 /* Handle gnu_inline attribute. */
6108 if (declspecs->inline_p
6109 && !flag_gnu89_inline
6110 && TREE_CODE (decl1) == FUNCTION_DECL
6111 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl1)))
6113 if (declspecs->storage_class != csc_static)
6114 DECL_EXTERNAL (decl1) = !DECL_EXTERNAL (decl1);
6117 announce_function (decl1);
6119 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6121 error ("return type is an incomplete type");
6122 /* Make it return void instead. */
6123 TREE_TYPE (decl1)
6124 = build_function_type (void_type_node,
6125 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6128 if (warn_about_return_type)
6129 pedwarn_c99 ("return type defaults to %<int%>");
6131 /* Make the init_value nonzero so pushdecl knows this is not tentative.
6132 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
6133 DECL_INITIAL (decl1) = error_mark_node;
6135 /* If this definition isn't a prototype and we had a prototype declaration
6136 before, copy the arg type info from that prototype. */
6137 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
6138 if (old_decl && TREE_CODE (old_decl) != FUNCTION_DECL)
6139 old_decl = 0;
6140 current_function_prototype_locus = UNKNOWN_LOCATION;
6141 current_function_prototype_built_in = false;
6142 current_function_prototype_arg_types = NULL_TREE;
6143 if (TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6145 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6146 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6147 TREE_TYPE (TREE_TYPE (old_decl))))
6149 TREE_TYPE (decl1) = composite_type (TREE_TYPE (old_decl),
6150 TREE_TYPE (decl1));
6151 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
6152 current_function_prototype_built_in
6153 = C_DECL_BUILTIN_PROTOTYPE (old_decl);
6154 current_function_prototype_arg_types
6155 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
6157 if (TREE_PUBLIC (decl1))
6159 /* If there is an external prototype declaration of this
6160 function, record its location but do not copy information
6161 to this decl. This may be an invisible declaration
6162 (built-in or in a scope which has finished) or simply
6163 have more refined argument types than any declaration
6164 found above. */
6165 struct c_binding *b;
6166 for (b = I_SYMBOL_BINDING (DECL_NAME (decl1)); b; b = b->shadowed)
6167 if (B_IN_SCOPE (b, external_scope))
6168 break;
6169 if (b)
6171 tree ext_decl, ext_type;
6172 ext_decl = b->decl;
6173 ext_type = b->type ? b->type : TREE_TYPE (ext_decl);
6174 if (TREE_CODE (ext_type) == FUNCTION_TYPE
6175 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6176 TREE_TYPE (ext_type)))
6178 current_function_prototype_locus
6179 = DECL_SOURCE_LOCATION (ext_decl);
6180 current_function_prototype_built_in
6181 = C_DECL_BUILTIN_PROTOTYPE (ext_decl);
6182 current_function_prototype_arg_types
6183 = TYPE_ARG_TYPES (ext_type);
6189 /* Optionally warn of old-fashioned def with no previous prototype. */
6190 if (warn_strict_prototypes
6191 && old_decl != error_mark_node
6192 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6193 && C_DECL_ISNT_PROTOTYPE (old_decl))
6194 warning (OPT_Wstrict_prototypes,
6195 "function declaration isn%'t a prototype");
6196 /* Optionally warn of any global def with no previous prototype. */
6197 else if (warn_missing_prototypes
6198 && old_decl != error_mark_node
6199 && TREE_PUBLIC (decl1)
6200 && !MAIN_NAME_P (DECL_NAME (decl1))
6201 && C_DECL_ISNT_PROTOTYPE (old_decl))
6202 warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl1);
6203 /* Optionally warn of any def with no previous prototype
6204 if the function has already been used. */
6205 else if (warn_missing_prototypes
6206 && old_decl != 0
6207 && old_decl != error_mark_node
6208 && TREE_USED (old_decl)
6209 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6210 warning (OPT_Wmissing_prototypes,
6211 "%q+D was used with no prototype before its definition", decl1);
6212 /* Optionally warn of any global def with no previous declaration. */
6213 else if (warn_missing_declarations
6214 && TREE_PUBLIC (decl1)
6215 && old_decl == 0
6216 && !MAIN_NAME_P (DECL_NAME (decl1)))
6217 warning (OPT_Wmissing_declarations, "no previous declaration for %q+D",
6218 decl1);
6219 /* Optionally warn of any def with no previous declaration
6220 if the function has already been used. */
6221 else if (warn_missing_declarations
6222 && old_decl != 0
6223 && old_decl != error_mark_node
6224 && TREE_USED (old_decl)
6225 && C_DECL_IMPLICIT (old_decl))
6226 warning (OPT_Wmissing_declarations,
6227 "%q+D was used with no declaration before its definition", decl1);
6229 /* This function exists in static storage.
6230 (This does not mean `static' in the C sense!) */
6231 TREE_STATIC (decl1) = 1;
6233 /* A nested function is not global. */
6234 if (current_function_decl != 0)
6235 TREE_PUBLIC (decl1) = 0;
6237 /* This is the earliest point at which we might know the assembler
6238 name of the function. Thus, if it's set before this, die horribly. */
6239 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl1));
6241 /* If #pragma weak was used, mark the decl weak now. */
6242 if (current_scope == file_scope)
6243 maybe_apply_pragma_weak (decl1);
6245 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6246 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6248 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6249 != integer_type_node)
6250 pedwarn ("return type of %q+D is not %<int%>", decl1);
6252 check_main_parameter_types(decl1);
6254 if (!TREE_PUBLIC (decl1))
6255 pedwarn ("%q+D is normally a non-static function", decl1);
6258 /* Record the decl so that the function name is defined.
6259 If we already have a decl for this name, and it is a FUNCTION_DECL,
6260 use the old decl. */
6262 current_function_decl = pushdecl (decl1);
6264 push_scope ();
6265 declare_parm_level ();
6267 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6268 resdecl = build_decl (RESULT_DECL, NULL_TREE, restype);
6269 DECL_ARTIFICIAL (resdecl) = 1;
6270 DECL_IGNORED_P (resdecl) = 1;
6271 DECL_RESULT (current_function_decl) = resdecl;
6273 start_fname_decls ();
6275 return 1;
6278 /* Subroutine of store_parm_decls which handles new-style function
6279 definitions (prototype format). The parms already have decls, so we
6280 need only record them as in effect and complain if any redundant
6281 old-style parm decls were written. */
6282 static void
6283 store_parm_decls_newstyle (tree fndecl, const struct c_arg_info *arg_info)
6285 tree decl;
6287 if (current_scope->bindings)
6289 error ("%Jold-style parameter declarations in prototyped "
6290 "function definition", fndecl);
6292 /* Get rid of the old-style declarations. */
6293 pop_scope ();
6294 push_scope ();
6296 /* Don't issue this warning for nested functions, and don't issue this
6297 warning if we got here because ARG_INFO_TYPES was error_mark_node
6298 (this happens when a function definition has just an ellipsis in
6299 its parameter list). */
6300 else if (!in_system_header && !current_function_scope
6301 && arg_info->types != error_mark_node)
6302 warning (OPT_Wtraditional,
6303 "%Jtraditional C rejects ISO C style function definitions",
6304 fndecl);
6306 /* Now make all the parameter declarations visible in the function body.
6307 We can bypass most of the grunt work of pushdecl. */
6308 for (decl = arg_info->parms; decl; decl = TREE_CHAIN (decl))
6310 DECL_CONTEXT (decl) = current_function_decl;
6311 if (DECL_NAME (decl))
6313 bind (DECL_NAME (decl), decl, current_scope,
6314 /*invisible=*/false, /*nested=*/false);
6315 if (!TREE_USED (decl))
6316 warn_if_shadowing (decl);
6318 else
6319 error ("%Jparameter name omitted", decl);
6322 /* Record the parameter list in the function declaration. */
6323 DECL_ARGUMENTS (fndecl) = arg_info->parms;
6325 /* Now make all the ancillary declarations visible, likewise. */
6326 for (decl = arg_info->others; decl; decl = TREE_CHAIN (decl))
6328 DECL_CONTEXT (decl) = current_function_decl;
6329 if (DECL_NAME (decl))
6330 bind (DECL_NAME (decl), decl, current_scope,
6331 /*invisible=*/false, /*nested=*/false);
6334 /* And all the tag declarations. */
6335 for (decl = arg_info->tags; decl; decl = TREE_CHAIN (decl))
6336 if (TREE_PURPOSE (decl))
6337 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
6338 /*invisible=*/false, /*nested=*/false);
6341 /* Subroutine of store_parm_decls which handles old-style function
6342 definitions (separate parameter list and declarations). */
6344 static void
6345 store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
6347 struct c_binding *b;
6348 tree parm, decl, last;
6349 tree parmids = arg_info->parms;
6350 struct pointer_set_t *seen_args = pointer_set_create ();
6352 if (!in_system_header)
6353 warning (OPT_Wold_style_definition, "%Jold-style function definition",
6354 fndecl);
6356 /* Match each formal parameter name with its declaration. Save each
6357 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
6358 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6360 if (TREE_VALUE (parm) == 0)
6362 error ("%Jparameter name missing from parameter list", fndecl);
6363 TREE_PURPOSE (parm) = 0;
6364 continue;
6367 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
6368 if (b && B_IN_CURRENT_SCOPE (b))
6370 decl = b->decl;
6371 /* If we got something other than a PARM_DECL it is an error. */
6372 if (TREE_CODE (decl) != PARM_DECL)
6373 error ("%q+D declared as a non-parameter", decl);
6374 /* If the declaration is already marked, we have a duplicate
6375 name. Complain and ignore the duplicate. */
6376 else if (pointer_set_contains (seen_args, decl))
6378 error ("multiple parameters named %q+D", decl);
6379 TREE_PURPOSE (parm) = 0;
6380 continue;
6382 /* If the declaration says "void", complain and turn it into
6383 an int. */
6384 else if (VOID_TYPE_P (TREE_TYPE (decl)))
6386 error ("parameter %q+D declared with void type", decl);
6387 TREE_TYPE (decl) = integer_type_node;
6388 DECL_ARG_TYPE (decl) = integer_type_node;
6389 layout_decl (decl, 0);
6391 warn_if_shadowing (decl);
6393 /* If no declaration found, default to int. */
6394 else
6396 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
6397 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
6398 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
6399 pushdecl (decl);
6400 warn_if_shadowing (decl);
6402 if (flag_isoc99)
6403 pedwarn ("type of %q+D defaults to %<int%>", decl);
6404 else
6405 warning (OPT_Wmissing_parameter_type, "type of %q+D defaults to %<int%>", decl);
6408 TREE_PURPOSE (parm) = decl;
6409 pointer_set_insert (seen_args, decl);
6412 /* Now examine the parms chain for incomplete declarations
6413 and declarations with no corresponding names. */
6415 for (b = current_scope->bindings; b; b = b->prev)
6417 parm = b->decl;
6418 if (TREE_CODE (parm) != PARM_DECL)
6419 continue;
6421 if (TREE_TYPE (parm) != error_mark_node
6422 && !COMPLETE_TYPE_P (TREE_TYPE (parm)))
6424 error ("parameter %q+D has incomplete type", parm);
6425 TREE_TYPE (parm) = error_mark_node;
6428 if (!pointer_set_contains (seen_args, parm))
6430 error ("declaration for parameter %q+D but no such parameter", parm);
6432 /* Pretend the parameter was not missing.
6433 This gets us to a standard state and minimizes
6434 further error messages. */
6435 parmids = chainon (parmids, tree_cons (parm, 0, 0));
6439 /* Chain the declarations together in the order of the list of
6440 names. Store that chain in the function decl, replacing the
6441 list of names. Update the current scope to match. */
6442 DECL_ARGUMENTS (fndecl) = 0;
6444 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6445 if (TREE_PURPOSE (parm))
6446 break;
6447 if (parm && TREE_PURPOSE (parm))
6449 last = TREE_PURPOSE (parm);
6450 DECL_ARGUMENTS (fndecl) = last;
6452 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
6453 if (TREE_PURPOSE (parm))
6455 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6456 last = TREE_PURPOSE (parm);
6458 TREE_CHAIN (last) = 0;
6461 pointer_set_destroy (seen_args);
6463 /* If there was a previous prototype,
6464 set the DECL_ARG_TYPE of each argument according to
6465 the type previously specified, and report any mismatches. */
6467 if (current_function_prototype_arg_types)
6469 tree type;
6470 for (parm = DECL_ARGUMENTS (fndecl),
6471 type = current_function_prototype_arg_types;
6472 parm || (type && TREE_VALUE (type) != error_mark_node
6473 && (TYPE_MAIN_VARIANT (TREE_VALUE (type)) != void_type_node));
6474 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6476 if (parm == 0 || type == 0
6477 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6479 if (current_function_prototype_built_in)
6480 warning (0, "number of arguments doesn%'t match "
6481 "built-in prototype");
6482 else
6484 error ("number of arguments doesn%'t match prototype");
6485 error ("%Hprototype declaration",
6486 &current_function_prototype_locus);
6488 break;
6490 /* Type for passing arg must be consistent with that
6491 declared for the arg. ISO C says we take the unqualified
6492 type for parameters declared with qualified type. */
6493 if (!comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6494 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6496 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6497 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6499 /* Adjust argument to match prototype. E.g. a previous
6500 `int foo(float);' prototype causes
6501 `int foo(x) float x; {...}' to be treated like
6502 `int foo(float x) {...}'. This is particularly
6503 useful for argument types like uid_t. */
6504 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6506 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6507 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6508 && TYPE_PRECISION (TREE_TYPE (parm))
6509 < TYPE_PRECISION (integer_type_node))
6510 DECL_ARG_TYPE (parm) = integer_type_node;
6512 if (pedantic)
6514 /* ??? Is it possible to get here with a
6515 built-in prototype or will it always have
6516 been diagnosed as conflicting with an
6517 old-style definition and discarded? */
6518 if (current_function_prototype_built_in)
6519 warning (0, "promoted argument %qD "
6520 "doesn%'t match built-in prototype", parm);
6521 else
6523 pedwarn ("promoted argument %qD "
6524 "doesn%'t match prototype", parm);
6525 pedwarn ("%Hprototype declaration",
6526 &current_function_prototype_locus);
6530 else
6532 if (current_function_prototype_built_in)
6533 warning (0, "argument %qD doesn%'t match "
6534 "built-in prototype", parm);
6535 else
6537 error ("argument %qD doesn%'t match prototype", parm);
6538 error ("%Hprototype declaration",
6539 &current_function_prototype_locus);
6544 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6547 /* Otherwise, create a prototype that would match. */
6549 else
6551 tree actual = 0, last = 0, type;
6553 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6555 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6556 if (last)
6557 TREE_CHAIN (last) = type;
6558 else
6559 actual = type;
6560 last = type;
6562 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6563 if (last)
6564 TREE_CHAIN (last) = type;
6565 else
6566 actual = type;
6568 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6569 of the type of this function, but we need to avoid having this
6570 affect the types of other similarly-typed functions, so we must
6571 first force the generation of an identical (but separate) type
6572 node for the relevant function type. The new node we create
6573 will be a variant of the main variant of the original function
6574 type. */
6576 TREE_TYPE (fndecl) = build_variant_type_copy (TREE_TYPE (fndecl));
6578 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6582 /* Store parameter declarations passed in ARG_INFO into the current
6583 function declaration. */
6585 void
6586 store_parm_decls_from (struct c_arg_info *arg_info)
6588 current_function_arg_info = arg_info;
6589 store_parm_decls ();
6592 /* Store the parameter declarations into the current function declaration.
6593 This is called after parsing the parameter declarations, before
6594 digesting the body of the function.
6596 For an old-style definition, construct a prototype out of the old-style
6597 parameter declarations and inject it into the function's type. */
6599 void
6600 store_parm_decls (void)
6602 tree fndecl = current_function_decl;
6603 bool proto;
6605 /* The argument information block for FNDECL. */
6606 struct c_arg_info *arg_info = current_function_arg_info;
6607 current_function_arg_info = 0;
6609 /* True if this definition is written with a prototype. Note:
6610 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6611 list in a function definition as equivalent to (void) -- an
6612 empty argument list specifies the function has no parameters,
6613 but only (void) sets up a prototype for future calls. */
6614 proto = arg_info->types != 0;
6616 if (proto)
6617 store_parm_decls_newstyle (fndecl, arg_info);
6618 else
6619 store_parm_decls_oldstyle (fndecl, arg_info);
6621 /* The next call to push_scope will be a function body. */
6623 next_is_function_body = true;
6625 /* Write a record describing this function definition to the prototypes
6626 file (if requested). */
6628 gen_aux_info_record (fndecl, 1, 0, proto);
6630 /* Initialize the RTL code for the function. */
6631 allocate_struct_function (fndecl);
6633 /* Begin the statement tree for this function. */
6634 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6636 /* ??? Insert the contents of the pending sizes list into the function
6637 to be evaluated. The only reason left to have this is
6638 void foo(int n, int array[n++])
6639 because we throw away the array type in favor of a pointer type, and
6640 thus won't naturally see the SAVE_EXPR containing the increment. All
6641 other pending sizes would be handled by gimplify_parameters. */
6643 tree t;
6644 for (t = nreverse (get_pending_sizes ()); t ; t = TREE_CHAIN (t))
6645 add_stmt (TREE_VALUE (t));
6648 /* Even though we're inside a function body, we still don't want to
6649 call expand_expr to calculate the size of a variable-sized array.
6650 We haven't necessarily assigned RTL to all variables yet, so it's
6651 not safe to try to expand expressions involving them. */
6652 cfun->x_dont_save_pending_sizes_p = 1;
6655 /* Emit diagnostics that require gimple input for detection. Operate on
6656 FNDECL and all its nested functions. */
6658 static void
6659 c_gimple_diagnostics_recursively (tree fndecl)
6661 struct cgraph_node *cgn;
6663 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6664 c_warn_unused_result (&DECL_SAVED_TREE (fndecl));
6666 /* Notice when OpenMP structured block constraints are violated. */
6667 if (flag_openmp)
6668 diagnose_omp_structured_block_errors (fndecl);
6670 /* Finalize all nested functions now. */
6671 cgn = cgraph_node (fndecl);
6672 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6673 c_gimple_diagnostics_recursively (cgn->decl);
6676 /* Finish up a function declaration and compile that function
6677 all the way to assembler language output. The free the storage
6678 for the function definition.
6680 This is called after parsing the body of the function definition. */
6682 void
6683 finish_function (void)
6685 tree fndecl = current_function_decl;
6687 label_context_stack_se = label_context_stack_se->next;
6688 label_context_stack_vm = label_context_stack_vm->next;
6690 if (TREE_CODE (fndecl) == FUNCTION_DECL
6691 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6693 tree args = DECL_ARGUMENTS (fndecl);
6694 for (; args; args = TREE_CHAIN (args))
6696 tree type = TREE_TYPE (args);
6697 if (INTEGRAL_TYPE_P (type)
6698 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6699 DECL_ARG_TYPE (args) = integer_type_node;
6703 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6704 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6706 /* Must mark the RESULT_DECL as being in this function. */
6708 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6709 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6711 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6713 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6714 != integer_type_node)
6716 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6717 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6718 if (!warn_main)
6719 pedwarn ("return type of %q+D is not %<int%>", fndecl);
6721 else
6723 if (flag_isoc99)
6725 tree stmt = c_finish_return (integer_zero_node);
6726 #ifdef USE_MAPPED_LOCATION
6727 /* Hack. We don't want the middle-end to warn that this return
6728 is unreachable, so we mark its location as special. Using
6729 UNKNOWN_LOCATION has the problem that it gets clobbered in
6730 annotate_one_with_locus. A cleaner solution might be to
6731 ensure ! should_carry_locus_p (stmt), but that needs a flag.
6733 SET_EXPR_LOCATION (stmt, BUILTINS_LOCATION);
6734 #else
6735 /* Hack. We don't want the middle-end to warn that this
6736 return is unreachable, so put the statement on the
6737 special line 0. */
6738 annotate_with_file_line (stmt, input_filename, 0);
6739 #endif
6744 /* Tie off the statement tree for this function. */
6745 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6747 finish_fname_decls ();
6749 /* Complain if there's just no return statement. */
6750 if (warn_return_type
6751 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6752 && !current_function_returns_value && !current_function_returns_null
6753 /* Don't complain if we are no-return. */
6754 && !current_function_returns_abnormally
6755 /* Don't warn for main(). */
6756 && !MAIN_NAME_P (DECL_NAME (fndecl))
6757 /* Or if they didn't actually specify a return type. */
6758 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6759 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6760 inline function, as we might never be compiled separately. */
6761 && DECL_INLINE (fndecl))
6763 warning (OPT_Wreturn_type,
6764 "no return statement in function returning non-void");
6765 TREE_NO_WARNING (fndecl) = 1;
6768 /* Store the end of the function, so that we get good line number
6769 info for the epilogue. */
6770 cfun->function_end_locus = input_location;
6772 /* Finalize the ELF visibility for the function. */
6773 c_determine_visibility (fndecl);
6775 /* For GNU C extern inline functions disregard inline limits. */
6776 if (DECL_EXTERNAL (fndecl)
6777 && DECL_DECLARED_INLINE_P (fndecl))
6778 DECL_DISREGARD_INLINE_LIMITS (fndecl) = 1;
6780 /* Genericize before inlining. Delay genericizing nested functions
6781 until their parent function is genericized. Since finalizing
6782 requires GENERIC, delay that as well. */
6784 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node
6785 && !undef_nested_function)
6787 if (!decl_function_context (fndecl))
6789 c_genericize (fndecl);
6790 c_gimple_diagnostics_recursively (fndecl);
6792 /* ??? Objc emits functions after finalizing the compilation unit.
6793 This should be cleaned up later and this conditional removed. */
6794 if (cgraph_global_info_ready)
6796 cgraph_add_new_function (fndecl, false);
6797 return;
6800 cgraph_finalize_function (fndecl, false);
6802 else
6804 /* Register this function with cgraph just far enough to get it
6805 added to our parent's nested function list. Handy, since the
6806 C front end doesn't have such a list. */
6807 (void) cgraph_node (fndecl);
6811 if (!decl_function_context (fndecl))
6812 undef_nested_function = false;
6814 /* We're leaving the context of this function, so zap cfun.
6815 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6816 tree_rest_of_compilation. */
6817 set_cfun (NULL);
6818 current_function_decl = NULL;
6821 /* Check the declarations given in a for-loop for satisfying the C99
6822 constraints. If exactly one such decl is found, return it. */
6824 tree
6825 check_for_loop_decls (void)
6827 struct c_binding *b;
6828 tree one_decl = NULL_TREE;
6829 int n_decls = 0;
6832 if (!flag_isoc99)
6834 /* If we get here, declarations have been used in a for loop without
6835 the C99 for loop scope. This doesn't make much sense, so don't
6836 allow it. */
6837 error ("%<for%> loop initial declaration used outside C99 mode");
6838 return NULL_TREE;
6840 /* C99 subclause 6.8.5 paragraph 3:
6842 [#3] The declaration part of a for statement shall only
6843 declare identifiers for objects having storage class auto or
6844 register.
6846 It isn't clear whether, in this sentence, "identifiers" binds to
6847 "shall only declare" or to "objects" - that is, whether all identifiers
6848 declared must be identifiers for objects, or whether the restriction
6849 only applies to those that are. (A question on this in comp.std.c
6850 in November 2000 received no answer.) We implement the strictest
6851 interpretation, to avoid creating an extension which later causes
6852 problems. */
6854 for (b = current_scope->bindings; b; b = b->prev)
6856 tree id = b->id;
6857 tree decl = b->decl;
6859 if (!id)
6860 continue;
6862 switch (TREE_CODE (decl))
6864 case VAR_DECL:
6865 if (TREE_STATIC (decl))
6866 error ("declaration of static variable %q+D in %<for%> loop "
6867 "initial declaration", decl);
6868 else if (DECL_EXTERNAL (decl))
6869 error ("declaration of %<extern%> variable %q+D in %<for%> loop "
6870 "initial declaration", decl);
6871 break;
6873 case RECORD_TYPE:
6874 error ("%<struct %E%> declared in %<for%> loop initial declaration",
6875 id);
6876 break;
6877 case UNION_TYPE:
6878 error ("%<union %E%> declared in %<for%> loop initial declaration",
6879 id);
6880 break;
6881 case ENUMERAL_TYPE:
6882 error ("%<enum %E%> declared in %<for%> loop initial declaration",
6883 id);
6884 break;
6885 default:
6886 error ("declaration of non-variable %q+D in %<for%> loop "
6887 "initial declaration", decl);
6890 n_decls++;
6891 one_decl = decl;
6894 return n_decls == 1 ? one_decl : NULL_TREE;
6897 /* Save and reinitialize the variables
6898 used during compilation of a C function. */
6900 void
6901 c_push_function_context (struct function *f)
6903 struct language_function *p;
6904 p = GGC_NEW (struct language_function);
6905 f->language = p;
6907 p->base.x_stmt_tree = c_stmt_tree;
6908 p->x_break_label = c_break_label;
6909 p->x_cont_label = c_cont_label;
6910 p->x_switch_stack = c_switch_stack;
6911 p->arg_info = current_function_arg_info;
6912 p->returns_value = current_function_returns_value;
6913 p->returns_null = current_function_returns_null;
6914 p->returns_abnormally = current_function_returns_abnormally;
6915 p->warn_about_return_type = warn_about_return_type;
6918 /* Restore the variables used during compilation of a C function. */
6920 void
6921 c_pop_function_context (struct function *f)
6923 struct language_function *p = f->language;
6925 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6926 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6928 /* Stop pointing to the local nodes about to be freed. */
6929 /* But DECL_INITIAL must remain nonzero so we know this
6930 was an actual function definition. */
6931 DECL_INITIAL (current_function_decl) = error_mark_node;
6932 DECL_ARGUMENTS (current_function_decl) = 0;
6935 c_stmt_tree = p->base.x_stmt_tree;
6936 c_break_label = p->x_break_label;
6937 c_cont_label = p->x_cont_label;
6938 c_switch_stack = p->x_switch_stack;
6939 current_function_arg_info = p->arg_info;
6940 current_function_returns_value = p->returns_value;
6941 current_function_returns_null = p->returns_null;
6942 current_function_returns_abnormally = p->returns_abnormally;
6943 warn_about_return_type = p->warn_about_return_type;
6945 f->language = NULL;
6948 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6950 void
6951 c_dup_lang_specific_decl (tree decl)
6953 struct lang_decl *ld;
6955 if (!DECL_LANG_SPECIFIC (decl))
6956 return;
6958 ld = GGC_NEW (struct lang_decl);
6959 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
6960 DECL_LANG_SPECIFIC (decl) = ld;
6963 /* The functions below are required for functionality of doing
6964 function at once processing in the C front end. Currently these
6965 functions are not called from anywhere in the C front end, but as
6966 these changes continue, that will change. */
6968 /* Returns the stmt_tree (if any) to which statements are currently
6969 being added. If there is no active statement-tree, NULL is
6970 returned. */
6972 stmt_tree
6973 current_stmt_tree (void)
6975 return &c_stmt_tree;
6978 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
6979 C. */
6982 anon_aggr_type_p (const_tree ARG_UNUSED (node))
6984 return 0;
6987 /* Return the global value of T as a symbol. */
6989 tree
6990 identifier_global_value (tree t)
6992 struct c_binding *b;
6994 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
6995 if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
6996 return b->decl;
6998 return 0;
7001 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
7002 otherwise the name is found in ridpointers from RID_INDEX. */
7004 void
7005 record_builtin_type (enum rid rid_index, const char *name, tree type)
7007 tree id, decl;
7008 if (name == 0)
7009 id = ridpointers[(int) rid_index];
7010 else
7011 id = get_identifier (name);
7012 decl = build_decl (TYPE_DECL, id, type);
7013 pushdecl (decl);
7014 if (debug_hooks->type_decl)
7015 debug_hooks->type_decl (decl, false);
7018 /* Build the void_list_node (void_type_node having been created). */
7019 tree
7020 build_void_list_node (void)
7022 tree t = build_tree_list (NULL_TREE, void_type_node);
7023 return t;
7026 /* Return a c_parm structure with the given SPECS, ATTRS and DECLARATOR. */
7028 struct c_parm *
7029 build_c_parm (struct c_declspecs *specs, tree attrs,
7030 struct c_declarator *declarator)
7032 struct c_parm *ret = XOBNEW (&parser_obstack, struct c_parm);
7033 ret->specs = specs;
7034 ret->attrs = attrs;
7035 ret->declarator = declarator;
7036 return ret;
7039 /* Return a declarator with nested attributes. TARGET is the inner
7040 declarator to which these attributes apply. ATTRS are the
7041 attributes. */
7043 struct c_declarator *
7044 build_attrs_declarator (tree attrs, struct c_declarator *target)
7046 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7047 ret->kind = cdk_attrs;
7048 ret->declarator = target;
7049 ret->u.attrs = attrs;
7050 return ret;
7053 /* Return a declarator for a function with arguments specified by ARGS
7054 and return type specified by TARGET. */
7056 struct c_declarator *
7057 build_function_declarator (struct c_arg_info *args,
7058 struct c_declarator *target)
7060 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7061 ret->kind = cdk_function;
7062 ret->declarator = target;
7063 ret->u.arg_info = args;
7064 return ret;
7067 /* Return a declarator for the identifier IDENT (which may be
7068 NULL_TREE for an abstract declarator). */
7070 struct c_declarator *
7071 build_id_declarator (tree ident)
7073 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7074 ret->kind = cdk_id;
7075 ret->declarator = 0;
7076 ret->u.id = ident;
7077 /* Default value - may get reset to a more precise location. */
7078 ret->id_loc = input_location;
7079 return ret;
7082 /* Return something to represent absolute declarators containing a *.
7083 TARGET is the absolute declarator that the * contains.
7084 TYPE_QUALS_ATTRS is a structure for type qualifiers and attributes
7085 to apply to the pointer type. */
7087 struct c_declarator *
7088 make_pointer_declarator (struct c_declspecs *type_quals_attrs,
7089 struct c_declarator *target)
7091 tree attrs;
7092 int quals = 0;
7093 struct c_declarator *itarget = target;
7094 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7095 if (type_quals_attrs)
7097 attrs = type_quals_attrs->attrs;
7098 quals = quals_from_declspecs (type_quals_attrs);
7099 if (attrs != NULL_TREE)
7100 itarget = build_attrs_declarator (attrs, target);
7102 ret->kind = cdk_pointer;
7103 ret->declarator = itarget;
7104 ret->u.pointer_quals = quals;
7105 return ret;
7108 /* Return a pointer to a structure for an empty list of declaration
7109 specifiers. */
7111 struct c_declspecs *
7112 build_null_declspecs (void)
7114 struct c_declspecs *ret = XOBNEW (&parser_obstack, struct c_declspecs);
7115 ret->type = 0;
7116 ret->decl_attr = 0;
7117 ret->attrs = 0;
7118 ret->typespec_word = cts_none;
7119 ret->storage_class = csc_none;
7120 ret->declspecs_seen_p = false;
7121 ret->type_seen_p = false;
7122 ret->non_sc_seen_p = false;
7123 ret->typedef_p = false;
7124 ret->tag_defined_p = false;
7125 ret->explicit_signed_p = false;
7126 ret->deprecated_p = false;
7127 ret->default_int_p = false;
7128 ret->long_p = false;
7129 ret->long_long_p = false;
7130 ret->short_p = false;
7131 ret->signed_p = false;
7132 ret->unsigned_p = false;
7133 ret->complex_p = false;
7134 ret->inline_p = false;
7135 ret->thread_p = false;
7136 ret->const_p = false;
7137 ret->volatile_p = false;
7138 ret->restrict_p = false;
7139 ret->saturating_p = false;
7140 return ret;
7143 /* Add the type qualifier QUAL to the declaration specifiers SPECS,
7144 returning SPECS. */
7146 struct c_declspecs *
7147 declspecs_add_qual (struct c_declspecs *specs, tree qual)
7149 enum rid i;
7150 bool dupe = false;
7151 specs->non_sc_seen_p = true;
7152 specs->declspecs_seen_p = true;
7153 gcc_assert (TREE_CODE (qual) == IDENTIFIER_NODE
7154 && C_IS_RESERVED_WORD (qual));
7155 i = C_RID_CODE (qual);
7156 switch (i)
7158 case RID_CONST:
7159 dupe = specs->const_p;
7160 specs->const_p = true;
7161 break;
7162 case RID_VOLATILE:
7163 dupe = specs->volatile_p;
7164 specs->volatile_p = true;
7165 break;
7166 case RID_RESTRICT:
7167 dupe = specs->restrict_p;
7168 specs->restrict_p = true;
7169 break;
7170 default:
7171 gcc_unreachable ();
7173 if (dupe && pedantic && !flag_isoc99)
7174 pedwarn ("duplicate %qE", qual);
7175 return specs;
7178 /* Add the type specifier TYPE to the declaration specifiers SPECS,
7179 returning SPECS. */
7181 struct c_declspecs *
7182 declspecs_add_type (struct c_declspecs *specs, struct c_typespec spec)
7184 tree type = spec.spec;
7185 specs->non_sc_seen_p = true;
7186 specs->declspecs_seen_p = true;
7187 specs->type_seen_p = true;
7188 if (TREE_DEPRECATED (type))
7189 specs->deprecated_p = true;
7191 /* Handle type specifier keywords. */
7192 if (TREE_CODE (type) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (type))
7194 enum rid i = C_RID_CODE (type);
7195 if (specs->type)
7197 error ("two or more data types in declaration specifiers");
7198 return specs;
7200 if ((int) i <= (int) RID_LAST_MODIFIER)
7202 /* "long", "short", "signed", "unsigned", "_Complex" or "_Sat". */
7203 bool dupe = false;
7204 switch (i)
7206 case RID_LONG:
7207 if (specs->long_long_p)
7209 error ("%<long long long%> is too long for GCC");
7210 break;
7212 if (specs->long_p)
7214 if (specs->typespec_word == cts_double)
7216 error ("both %<long long%> and %<double%> in "
7217 "declaration specifiers");
7218 break;
7220 if (pedantic && !flag_isoc99 && !in_system_header
7221 && warn_long_long)
7222 pedwarn ("ISO C90 does not support %<long long%>");
7223 specs->long_long_p = 1;
7224 break;
7226 if (specs->short_p)
7227 error ("both %<long%> and %<short%> in "
7228 "declaration specifiers");
7229 else if (specs->typespec_word == cts_void)
7230 error ("both %<long%> and %<void%> in "
7231 "declaration specifiers");
7232 else if (specs->typespec_word == cts_bool)
7233 error ("both %<long%> and %<_Bool%> in "
7234 "declaration specifiers");
7235 else if (specs->typespec_word == cts_char)
7236 error ("both %<long%> and %<char%> in "
7237 "declaration specifiers");
7238 else if (specs->typespec_word == cts_float)
7239 error ("both %<long%> and %<float%> in "
7240 "declaration specifiers");
7241 else if (specs->typespec_word == cts_dfloat32)
7242 error ("both %<long%> and %<_Decimal32%> in "
7243 "declaration specifiers");
7244 else if (specs->typespec_word == cts_dfloat64)
7245 error ("both %<long%> and %<_Decimal64%> in "
7246 "declaration specifiers");
7247 else if (specs->typespec_word == cts_dfloat128)
7248 error ("both %<long%> and %<_Decimal128%> in "
7249 "declaration specifiers");
7250 else
7251 specs->long_p = true;
7252 break;
7253 case RID_SHORT:
7254 dupe = specs->short_p;
7255 if (specs->long_p)
7256 error ("both %<long%> and %<short%> in "
7257 "declaration specifiers");
7258 else if (specs->typespec_word == cts_void)
7259 error ("both %<short%> and %<void%> in "
7260 "declaration specifiers");
7261 else if (specs->typespec_word == cts_bool)
7262 error ("both %<short%> and %<_Bool%> in "
7263 "declaration specifiers");
7264 else if (specs->typespec_word == cts_char)
7265 error ("both %<short%> and %<char%> in "
7266 "declaration specifiers");
7267 else if (specs->typespec_word == cts_float)
7268 error ("both %<short%> and %<float%> in "
7269 "declaration specifiers");
7270 else if (specs->typespec_word == cts_double)
7271 error ("both %<short%> and %<double%> in "
7272 "declaration specifiers");
7273 else if (specs->typespec_word == cts_dfloat32)
7274 error ("both %<short%> and %<_Decimal32%> in "
7275 "declaration specifiers");
7276 else if (specs->typespec_word == cts_dfloat64)
7277 error ("both %<short%> and %<_Decimal64%> in "
7278 "declaration specifiers");
7279 else if (specs->typespec_word == cts_dfloat128)
7280 error ("both %<short%> and %<_Decimal128%> in "
7281 "declaration specifiers");
7282 else
7283 specs->short_p = true;
7284 break;
7285 case RID_SIGNED:
7286 dupe = specs->signed_p;
7287 if (specs->unsigned_p)
7288 error ("both %<signed%> and %<unsigned%> in "
7289 "declaration specifiers");
7290 else if (specs->typespec_word == cts_void)
7291 error ("both %<signed%> and %<void%> in "
7292 "declaration specifiers");
7293 else if (specs->typespec_word == cts_bool)
7294 error ("both %<signed%> and %<_Bool%> in "
7295 "declaration specifiers");
7296 else if (specs->typespec_word == cts_float)
7297 error ("both %<signed%> and %<float%> in "
7298 "declaration specifiers");
7299 else if (specs->typespec_word == cts_double)
7300 error ("both %<signed%> and %<double%> in "
7301 "declaration specifiers");
7302 else if (specs->typespec_word == cts_dfloat32)
7303 error ("both %<signed%> and %<_Decimal32%> in "
7304 "declaration specifiers");
7305 else if (specs->typespec_word == cts_dfloat64)
7306 error ("both %<signed%> and %<_Decimal64%> in "
7307 "declaration specifiers");
7308 else if (specs->typespec_word == cts_dfloat128)
7309 error ("both %<signed%> and %<_Decimal128%> in "
7310 "declaration specifiers");
7311 else
7312 specs->signed_p = true;
7313 break;
7314 case RID_UNSIGNED:
7315 dupe = specs->unsigned_p;
7316 if (specs->signed_p)
7317 error ("both %<signed%> and %<unsigned%> in "
7318 "declaration specifiers");
7319 else if (specs->typespec_word == cts_void)
7320 error ("both %<unsigned%> and %<void%> in "
7321 "declaration specifiers");
7322 else if (specs->typespec_word == cts_bool)
7323 error ("both %<unsigned%> and %<_Bool%> in "
7324 "declaration specifiers");
7325 else if (specs->typespec_word == cts_float)
7326 error ("both %<unsigned%> and %<float%> in "
7327 "declaration specifiers");
7328 else if (specs->typespec_word == cts_double)
7329 error ("both %<unsigned%> and %<double%> in "
7330 "declaration specifiers");
7331 else if (specs->typespec_word == cts_dfloat32)
7332 error ("both %<unsigned%> and %<_Decimal32%> in "
7333 "declaration specifiers");
7334 else if (specs->typespec_word == cts_dfloat64)
7335 error ("both %<unsigned%> and %<_Decimal64%> in "
7336 "declaration specifiers");
7337 else if (specs->typespec_word == cts_dfloat128)
7338 error ("both %<unsigned%> and %<_Decimal128%> in "
7339 "declaration specifiers");
7340 else
7341 specs->unsigned_p = true;
7342 break;
7343 case RID_COMPLEX:
7344 dupe = specs->complex_p;
7345 if (pedantic && !flag_isoc99 && !in_system_header)
7346 pedwarn ("ISO C90 does not support complex types");
7347 if (specs->typespec_word == cts_void)
7348 error ("both %<complex%> and %<void%> in "
7349 "declaration specifiers");
7350 else if (specs->typespec_word == cts_bool)
7351 error ("both %<complex%> and %<_Bool%> in "
7352 "declaration specifiers");
7353 else if (specs->typespec_word == cts_dfloat32)
7354 error ("both %<complex%> and %<_Decimal32%> in "
7355 "declaration specifiers");
7356 else if (specs->typespec_word == cts_dfloat64)
7357 error ("both %<complex%> and %<_Decimal64%> in "
7358 "declaration specifiers");
7359 else if (specs->typespec_word == cts_dfloat128)
7360 error ("both %<complex%> and %<_Decimal128%> in "
7361 "declaration specifiers");
7362 else if (specs->typespec_word == cts_fract)
7363 error ("both %<complex%> and %<_Fract%> in "
7364 "declaration specifiers");
7365 else if (specs->typespec_word == cts_accum)
7366 error ("both %<complex%> and %<_Accum%> in "
7367 "declaration specifiers");
7368 else if (specs->saturating_p)
7369 error ("both %<complex%> and %<_Sat%> in "
7370 "declaration specifiers");
7371 else
7372 specs->complex_p = true;
7373 break;
7374 case RID_SAT:
7375 dupe = specs->saturating_p;
7376 if (pedantic)
7377 pedwarn ("ISO C does not support saturating types");
7378 if (specs->typespec_word == cts_void)
7379 error ("both %<_Sat%> and %<void%> in "
7380 "declaration specifiers");
7381 else if (specs->typespec_word == cts_bool)
7382 error ("both %<_Sat%> and %<_Bool%> in "
7383 "declaration specifiers");
7384 else if (specs->typespec_word == cts_char)
7385 error ("both %<_Sat%> and %<char%> in "
7386 "declaration specifiers");
7387 else if (specs->typespec_word == cts_int)
7388 error ("both %<_Sat%> and %<int%> in "
7389 "declaration specifiers");
7390 else if (specs->typespec_word == cts_float)
7391 error ("both %<_Sat%> and %<float%> in "
7392 "declaration specifiers");
7393 else if (specs->typespec_word == cts_double)
7394 error ("both %<_Sat%> and %<double%> in "
7395 "declaration specifiers");
7396 else if (specs->typespec_word == cts_dfloat32)
7397 error ("both %<_Sat%> and %<_Decimal32%> in "
7398 "declaration specifiers");
7399 else if (specs->typespec_word == cts_dfloat64)
7400 error ("both %<_Sat%> and %<_Decimal64%> in "
7401 "declaration specifiers");
7402 else if (specs->typespec_word == cts_dfloat128)
7403 error ("both %<_Sat%> and %<_Decimal128%> in "
7404 "declaration specifiers");
7405 else if (specs->complex_p)
7406 error ("both %<_Sat%> and %<complex%> in "
7407 "declaration specifiers");
7408 else
7409 specs->saturating_p = true;
7410 break;
7411 default:
7412 gcc_unreachable ();
7415 if (dupe)
7416 error ("duplicate %qE", type);
7418 return specs;
7420 else
7422 /* "void", "_Bool", "char", "int", "float", "double", "_Decimal32",
7423 "_Decimal64", "_Decimal128", "_Fract" or "_Accum". */
7424 if (specs->typespec_word != cts_none)
7426 error ("two or more data types in declaration specifiers");
7427 return specs;
7429 switch (i)
7431 case RID_VOID:
7432 if (specs->long_p)
7433 error ("both %<long%> and %<void%> in "
7434 "declaration specifiers");
7435 else if (specs->short_p)
7436 error ("both %<short%> and %<void%> in "
7437 "declaration specifiers");
7438 else if (specs->signed_p)
7439 error ("both %<signed%> and %<void%> in "
7440 "declaration specifiers");
7441 else if (specs->unsigned_p)
7442 error ("both %<unsigned%> and %<void%> in "
7443 "declaration specifiers");
7444 else if (specs->complex_p)
7445 error ("both %<complex%> and %<void%> in "
7446 "declaration specifiers");
7447 else if (specs->saturating_p)
7448 error ("both %<_Sat%> and %<void%> in "
7449 "declaration specifiers");
7450 else
7451 specs->typespec_word = cts_void;
7452 return specs;
7453 case RID_BOOL:
7454 if (specs->long_p)
7455 error ("both %<long%> and %<_Bool%> in "
7456 "declaration specifiers");
7457 else if (specs->short_p)
7458 error ("both %<short%> and %<_Bool%> in "
7459 "declaration specifiers");
7460 else if (specs->signed_p)
7461 error ("both %<signed%> and %<_Bool%> in "
7462 "declaration specifiers");
7463 else if (specs->unsigned_p)
7464 error ("both %<unsigned%> and %<_Bool%> in "
7465 "declaration specifiers");
7466 else if (specs->complex_p)
7467 error ("both %<complex%> and %<_Bool%> in "
7468 "declaration specifiers");
7469 else if (specs->saturating_p)
7470 error ("both %<_Sat%> and %<_Bool%> in "
7471 "declaration specifiers");
7472 else
7473 specs->typespec_word = cts_bool;
7474 return specs;
7475 case RID_CHAR:
7476 if (specs->long_p)
7477 error ("both %<long%> and %<char%> in "
7478 "declaration specifiers");
7479 else if (specs->short_p)
7480 error ("both %<short%> and %<char%> in "
7481 "declaration specifiers");
7482 else if (specs->saturating_p)
7483 error ("both %<_Sat%> and %<char%> in "
7484 "declaration specifiers");
7485 else
7486 specs->typespec_word = cts_char;
7487 return specs;
7488 case RID_INT:
7489 if (specs->saturating_p)
7490 error ("both %<_Sat%> and %<int%> in "
7491 "declaration specifiers");
7492 else
7493 specs->typespec_word = cts_int;
7494 return specs;
7495 case RID_FLOAT:
7496 if (specs->long_p)
7497 error ("both %<long%> and %<float%> in "
7498 "declaration specifiers");
7499 else if (specs->short_p)
7500 error ("both %<short%> and %<float%> in "
7501 "declaration specifiers");
7502 else if (specs->signed_p)
7503 error ("both %<signed%> and %<float%> in "
7504 "declaration specifiers");
7505 else if (specs->unsigned_p)
7506 error ("both %<unsigned%> and %<float%> in "
7507 "declaration specifiers");
7508 else if (specs->saturating_p)
7509 error ("both %<_Sat%> and %<float%> in "
7510 "declaration specifiers");
7511 else
7512 specs->typespec_word = cts_float;
7513 return specs;
7514 case RID_DOUBLE:
7515 if (specs->long_long_p)
7516 error ("both %<long long%> and %<double%> in "
7517 "declaration specifiers");
7518 else if (specs->short_p)
7519 error ("both %<short%> and %<double%> in "
7520 "declaration specifiers");
7521 else if (specs->signed_p)
7522 error ("both %<signed%> and %<double%> in "
7523 "declaration specifiers");
7524 else if (specs->unsigned_p)
7525 error ("both %<unsigned%> and %<double%> in "
7526 "declaration specifiers");
7527 else if (specs->saturating_p)
7528 error ("both %<_Sat%> and %<double%> in "
7529 "declaration specifiers");
7530 else
7531 specs->typespec_word = cts_double;
7532 return specs;
7533 case RID_DFLOAT32:
7534 case RID_DFLOAT64:
7535 case RID_DFLOAT128:
7537 const char *str;
7538 if (i == RID_DFLOAT32)
7539 str = "_Decimal32";
7540 else if (i == RID_DFLOAT64)
7541 str = "_Decimal64";
7542 else
7543 str = "_Decimal128";
7544 if (specs->long_long_p)
7545 error ("both %<long long%> and %<%s%> in "
7546 "declaration specifiers", str);
7547 if (specs->long_p)
7548 error ("both %<long%> and %<%s%> in "
7549 "declaration specifiers", str);
7550 else if (specs->short_p)
7551 error ("both %<short%> and %<%s%> in "
7552 "declaration specifiers", str);
7553 else if (specs->signed_p)
7554 error ("both %<signed%> and %<%s%> in "
7555 "declaration specifiers", str);
7556 else if (specs->unsigned_p)
7557 error ("both %<unsigned%> and %<%s%> in "
7558 "declaration specifiers", str);
7559 else if (specs->complex_p)
7560 error ("both %<complex%> and %<%s%> in "
7561 "declaration specifiers", str);
7562 else if (specs->saturating_p)
7563 error ("both %<_Sat%> and %<%s%> in "
7564 "declaration specifiers", str);
7565 else if (i == RID_DFLOAT32)
7566 specs->typespec_word = cts_dfloat32;
7567 else if (i == RID_DFLOAT64)
7568 specs->typespec_word = cts_dfloat64;
7569 else
7570 specs->typespec_word = cts_dfloat128;
7572 if (!targetm.decimal_float_supported_p ())
7573 error ("decimal floating point not supported for this target");
7574 if (pedantic)
7575 pedwarn ("ISO C does not support decimal floating point");
7576 return specs;
7577 case RID_FRACT:
7578 case RID_ACCUM:
7580 const char *str;
7581 if (i == RID_FRACT)
7582 str = "_Fract";
7583 else
7584 str = "_Accum";
7585 if (specs->complex_p)
7586 error ("both %<complex%> and %<%s%> in "
7587 "declaration specifiers", str);
7588 else if (i == RID_FRACT)
7589 specs->typespec_word = cts_fract;
7590 else
7591 specs->typespec_word = cts_accum;
7593 if (!targetm.fixed_point_supported_p ())
7594 error ("fixed-point types not supported for this target");
7595 if (pedantic)
7596 pedwarn ("ISO C does not support fixed-point types");
7597 return specs;
7598 default:
7599 /* ObjC reserved word "id", handled below. */
7600 break;
7605 /* Now we have a typedef (a TYPE_DECL node), an identifier (some
7606 form of ObjC type, cases such as "int" and "long" being handled
7607 above), a TYPE (struct, union, enum and typeof specifiers) or an
7608 ERROR_MARK. In none of these cases may there have previously
7609 been any type specifiers. */
7610 if (specs->type || specs->typespec_word != cts_none
7611 || specs->long_p || specs->short_p || specs->signed_p
7612 || specs->unsigned_p || specs->complex_p)
7613 error ("two or more data types in declaration specifiers");
7614 else if (TREE_CODE (type) == TYPE_DECL)
7616 if (TREE_TYPE (type) == error_mark_node)
7617 ; /* Allow the type to default to int to avoid cascading errors. */
7618 else
7620 specs->type = TREE_TYPE (type);
7621 specs->decl_attr = DECL_ATTRIBUTES (type);
7622 specs->typedef_p = true;
7623 specs->explicit_signed_p = C_TYPEDEF_EXPLICITLY_SIGNED (type);
7626 else if (TREE_CODE (type) == IDENTIFIER_NODE)
7628 tree t = lookup_name (type);
7629 if (!t || TREE_CODE (t) != TYPE_DECL)
7630 error ("%qE fails to be a typedef or built in type", type);
7631 else if (TREE_TYPE (t) == error_mark_node)
7633 else
7634 specs->type = TREE_TYPE (t);
7636 else if (TREE_CODE (type) != ERROR_MARK)
7638 if (spec.kind == ctsk_tagdef || spec.kind == ctsk_tagfirstref)
7639 specs->tag_defined_p = true;
7640 if (spec.kind == ctsk_typeof)
7641 specs->typedef_p = true;
7642 specs->type = type;
7645 return specs;
7648 /* Add the storage class specifier or function specifier SCSPEC to the
7649 declaration specifiers SPECS, returning SPECS. */
7651 struct c_declspecs *
7652 declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
7654 enum rid i;
7655 enum c_storage_class n = csc_none;
7656 bool dupe = false;
7657 specs->declspecs_seen_p = true;
7658 gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
7659 && C_IS_RESERVED_WORD (scspec));
7660 i = C_RID_CODE (scspec);
7661 if (specs->non_sc_seen_p)
7662 warning (OPT_Wold_style_declaration,
7663 "%qE is not at beginning of declaration", scspec);
7664 switch (i)
7666 case RID_INLINE:
7667 /* C99 permits duplicate inline. Although of doubtful utility,
7668 it seems simplest to permit it in gnu89 mode as well, as
7669 there is also little utility in maintaining this as a
7670 difference between gnu89 and C99 inline. */
7671 dupe = false;
7672 specs->inline_p = true;
7673 break;
7674 case RID_THREAD:
7675 dupe = specs->thread_p;
7676 if (specs->storage_class == csc_auto)
7677 error ("%<__thread%> used with %<auto%>");
7678 else if (specs->storage_class == csc_register)
7679 error ("%<__thread%> used with %<register%>");
7680 else if (specs->storage_class == csc_typedef)
7681 error ("%<__thread%> used with %<typedef%>");
7682 else
7683 specs->thread_p = true;
7684 break;
7685 case RID_AUTO:
7686 n = csc_auto;
7687 break;
7688 case RID_EXTERN:
7689 n = csc_extern;
7690 /* Diagnose "__thread extern". */
7691 if (specs->thread_p)
7692 error ("%<__thread%> before %<extern%>");
7693 break;
7694 case RID_REGISTER:
7695 n = csc_register;
7696 break;
7697 case RID_STATIC:
7698 n = csc_static;
7699 /* Diagnose "__thread static". */
7700 if (specs->thread_p)
7701 error ("%<__thread%> before %<static%>");
7702 break;
7703 case RID_TYPEDEF:
7704 n = csc_typedef;
7705 break;
7706 default:
7707 gcc_unreachable ();
7709 if (n != csc_none && n == specs->storage_class)
7710 dupe = true;
7711 if (dupe)
7712 error ("duplicate %qE", scspec);
7713 if (n != csc_none)
7715 if (specs->storage_class != csc_none && n != specs->storage_class)
7717 error ("multiple storage classes in declaration specifiers");
7719 else
7721 specs->storage_class = n;
7722 if (n != csc_extern && n != csc_static && specs->thread_p)
7724 error ("%<__thread%> used with %qE", scspec);
7725 specs->thread_p = false;
7729 return specs;
7732 /* Add the attributes ATTRS to the declaration specifiers SPECS,
7733 returning SPECS. */
7735 struct c_declspecs *
7736 declspecs_add_attrs (struct c_declspecs *specs, tree attrs)
7738 specs->attrs = chainon (attrs, specs->attrs);
7739 specs->declspecs_seen_p = true;
7740 return specs;
7743 /* Combine "long", "short", "signed", "unsigned" and "_Complex" type
7744 specifiers with any other type specifier to determine the resulting
7745 type. This is where ISO C checks on complex types are made, since
7746 "_Complex long" is a prefix of the valid ISO C type "_Complex long
7747 double". */
7749 struct c_declspecs *
7750 finish_declspecs (struct c_declspecs *specs)
7752 /* If a type was specified as a whole, we have no modifiers and are
7753 done. */
7754 if (specs->type != NULL_TREE)
7756 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7757 && !specs->signed_p && !specs->unsigned_p
7758 && !specs->complex_p);
7759 return specs;
7762 /* If none of "void", "_Bool", "char", "int", "float" or "double"
7763 has been specified, treat it as "int" unless "_Complex" is
7764 present and there are no other specifiers. If we just have
7765 "_Complex", it is equivalent to "_Complex double", but e.g.
7766 "_Complex short" is equivalent to "_Complex short int". */
7767 if (specs->typespec_word == cts_none)
7769 if (specs->saturating_p)
7771 error ("%<_Sat%> is used without %<_Fract%> or %<_Accum%>");
7772 specs->typespec_word = cts_fract;
7774 else if (specs->long_p || specs->short_p
7775 || specs->signed_p || specs->unsigned_p)
7777 specs->typespec_word = cts_int;
7779 else if (specs->complex_p)
7781 specs->typespec_word = cts_double;
7782 if (pedantic)
7783 pedwarn ("ISO C does not support plain %<complex%> meaning "
7784 "%<double complex%>");
7786 else
7788 specs->typespec_word = cts_int;
7789 specs->default_int_p = true;
7790 /* We don't diagnose this here because grokdeclarator will
7791 give more specific diagnostics according to whether it is
7792 a function definition. */
7796 /* If "signed" was specified, record this to distinguish "int" and
7797 "signed int" in the case of a bit-field with
7798 -funsigned-bitfields. */
7799 specs->explicit_signed_p = specs->signed_p;
7801 /* Now compute the actual type. */
7802 switch (specs->typespec_word)
7804 case cts_void:
7805 gcc_assert (!specs->long_p && !specs->short_p
7806 && !specs->signed_p && !specs->unsigned_p
7807 && !specs->complex_p);
7808 specs->type = void_type_node;
7809 break;
7810 case cts_bool:
7811 gcc_assert (!specs->long_p && !specs->short_p
7812 && !specs->signed_p && !specs->unsigned_p
7813 && !specs->complex_p);
7814 specs->type = boolean_type_node;
7815 break;
7816 case cts_char:
7817 gcc_assert (!specs->long_p && !specs->short_p);
7818 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7819 if (specs->signed_p)
7820 specs->type = signed_char_type_node;
7821 else if (specs->unsigned_p)
7822 specs->type = unsigned_char_type_node;
7823 else
7824 specs->type = char_type_node;
7825 if (specs->complex_p)
7827 if (pedantic)
7828 pedwarn ("ISO C does not support complex integer types");
7829 specs->type = build_complex_type (specs->type);
7831 break;
7832 case cts_int:
7833 gcc_assert (!(specs->long_p && specs->short_p));
7834 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7835 if (specs->long_long_p)
7836 specs->type = (specs->unsigned_p
7837 ? long_long_unsigned_type_node
7838 : long_long_integer_type_node);
7839 else if (specs->long_p)
7840 specs->type = (specs->unsigned_p
7841 ? long_unsigned_type_node
7842 : long_integer_type_node);
7843 else if (specs->short_p)
7844 specs->type = (specs->unsigned_p
7845 ? short_unsigned_type_node
7846 : short_integer_type_node);
7847 else
7848 specs->type = (specs->unsigned_p
7849 ? unsigned_type_node
7850 : integer_type_node);
7851 if (specs->complex_p)
7853 if (pedantic)
7854 pedwarn ("ISO C does not support complex integer types");
7855 specs->type = build_complex_type (specs->type);
7857 break;
7858 case cts_float:
7859 gcc_assert (!specs->long_p && !specs->short_p
7860 && !specs->signed_p && !specs->unsigned_p);
7861 specs->type = (specs->complex_p
7862 ? complex_float_type_node
7863 : float_type_node);
7864 break;
7865 case cts_double:
7866 gcc_assert (!specs->long_long_p && !specs->short_p
7867 && !specs->signed_p && !specs->unsigned_p);
7868 if (specs->long_p)
7870 specs->type = (specs->complex_p
7871 ? complex_long_double_type_node
7872 : long_double_type_node);
7874 else
7876 specs->type = (specs->complex_p
7877 ? complex_double_type_node
7878 : double_type_node);
7880 break;
7881 case cts_dfloat32:
7882 case cts_dfloat64:
7883 case cts_dfloat128:
7884 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7885 && !specs->signed_p && !specs->unsigned_p && !specs->complex_p);
7886 if (specs->typespec_word == cts_dfloat32)
7887 specs->type = dfloat32_type_node;
7888 else if (specs->typespec_word == cts_dfloat64)
7889 specs->type = dfloat64_type_node;
7890 else
7891 specs->type = dfloat128_type_node;
7892 break;
7893 case cts_fract:
7894 gcc_assert (!specs->complex_p);
7895 if (specs->saturating_p)
7897 if (specs->long_long_p)
7898 specs->type = specs->unsigned_p
7899 ? sat_unsigned_long_long_fract_type_node
7900 : sat_long_long_fract_type_node;
7901 else if (specs->long_p)
7902 specs->type = specs->unsigned_p
7903 ? sat_unsigned_long_fract_type_node
7904 : sat_long_fract_type_node;
7905 else if (specs->short_p)
7906 specs->type = specs->unsigned_p
7907 ? sat_unsigned_short_fract_type_node
7908 : sat_short_fract_type_node;
7909 else
7910 specs->type = specs->unsigned_p
7911 ? sat_unsigned_fract_type_node
7912 : sat_fract_type_node;
7914 else
7916 if (specs->long_long_p)
7917 specs->type = specs->unsigned_p
7918 ? unsigned_long_long_fract_type_node
7919 : long_long_fract_type_node;
7920 else if (specs->long_p)
7921 specs->type = specs->unsigned_p
7922 ? unsigned_long_fract_type_node
7923 : long_fract_type_node;
7924 else if (specs->short_p)
7925 specs->type = specs->unsigned_p
7926 ? unsigned_short_fract_type_node
7927 : short_fract_type_node;
7928 else
7929 specs->type = specs->unsigned_p
7930 ? unsigned_fract_type_node
7931 : fract_type_node;
7933 break;
7934 case cts_accum:
7935 gcc_assert (!specs->complex_p);
7936 if (specs->saturating_p)
7938 if (specs->long_long_p)
7939 specs->type = specs->unsigned_p
7940 ? sat_unsigned_long_long_accum_type_node
7941 : sat_long_long_accum_type_node;
7942 else if (specs->long_p)
7943 specs->type = specs->unsigned_p
7944 ? sat_unsigned_long_accum_type_node
7945 : sat_long_accum_type_node;
7946 else if (specs->short_p)
7947 specs->type = specs->unsigned_p
7948 ? sat_unsigned_short_accum_type_node
7949 : sat_short_accum_type_node;
7950 else
7951 specs->type = specs->unsigned_p
7952 ? sat_unsigned_accum_type_node
7953 : sat_accum_type_node;
7955 else
7957 if (specs->long_long_p)
7958 specs->type = specs->unsigned_p
7959 ? unsigned_long_long_accum_type_node
7960 : long_long_accum_type_node;
7961 else if (specs->long_p)
7962 specs->type = specs->unsigned_p
7963 ? unsigned_long_accum_type_node
7964 : long_accum_type_node;
7965 else if (specs->short_p)
7966 specs->type = specs->unsigned_p
7967 ? unsigned_short_accum_type_node
7968 : short_accum_type_node;
7969 else
7970 specs->type = specs->unsigned_p
7971 ? unsigned_accum_type_node
7972 : accum_type_node;
7974 break;
7975 default:
7976 gcc_unreachable ();
7979 return specs;
7982 /* A subroutine of c_write_global_declarations. Perform final processing
7983 on one file scope's declarations (or the external scope's declarations),
7984 GLOBALS. */
7986 static void
7987 c_write_global_declarations_1 (tree globals)
7989 tree decl;
7990 bool reconsider;
7992 /* Process the decls in the order they were written. */
7993 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7995 /* Check for used but undefined static functions using the C
7996 standard's definition of "used", and set TREE_NO_WARNING so
7997 that check_global_declarations doesn't repeat the check. */
7998 if (TREE_CODE (decl) == FUNCTION_DECL
7999 && DECL_INITIAL (decl) == 0
8000 && DECL_EXTERNAL (decl)
8001 && !TREE_PUBLIC (decl)
8002 && C_DECL_USED (decl))
8004 pedwarn ("%q+F used but never defined", decl);
8005 TREE_NO_WARNING (decl) = 1;
8008 wrapup_global_declaration_1 (decl);
8013 reconsider = false;
8014 for (decl = globals; decl; decl = TREE_CHAIN (decl))
8015 reconsider |= wrapup_global_declaration_2 (decl);
8017 while (reconsider);
8019 for (decl = globals; decl; decl = TREE_CHAIN (decl))
8020 check_global_declaration_1 (decl);
8023 /* A subroutine of c_write_global_declarations Emit debug information for each
8024 of the declarations in GLOBALS. */
8026 static void
8027 c_write_global_declarations_2 (tree globals)
8029 tree decl;
8031 for (decl = globals; decl ; decl = TREE_CHAIN (decl))
8032 debug_hooks->global_decl (decl);
8035 /* Preserve the external declarations scope across a garbage collect. */
8036 static GTY(()) tree ext_block;
8038 void
8039 c_write_global_declarations (void)
8041 tree t;
8043 /* We don't want to do this if generating a PCH. */
8044 if (pch_file)
8045 return;
8047 /* Don't waste time on further processing if -fsyntax-only or we've
8048 encountered errors. */
8049 if (flag_syntax_only || errorcount || sorrycount || cpp_errors (parse_in))
8050 return;
8052 /* Close the external scope. */
8053 ext_block = pop_scope ();
8054 external_scope = 0;
8055 gcc_assert (!current_scope);
8057 if (ext_block)
8059 tree tmp = BLOCK_VARS (ext_block);
8060 int flags;
8061 FILE * stream = dump_begin (TDI_tu, &flags);
8062 if (stream && tmp)
8064 dump_node (tmp, flags & ~TDF_SLIM, stream);
8065 dump_end (TDI_tu, stream);
8069 /* Process all file scopes in this compilation, and the external_scope,
8070 through wrapup_global_declarations and check_global_declarations. */
8071 for (t = all_translation_units; t; t = TREE_CHAIN (t))
8072 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
8073 c_write_global_declarations_1 (BLOCK_VARS (ext_block));
8075 /* We're done parsing; proceed to optimize and emit assembly.
8076 FIXME: shouldn't be the front end's responsibility to call this. */
8077 cgraph_optimize ();
8079 /* After cgraph has had a chance to emit everything that's going to
8080 be emitted, output debug information for globals. */
8081 if (errorcount == 0 && sorrycount == 0)
8083 timevar_push (TV_SYMOUT);
8084 for (t = all_translation_units; t; t = TREE_CHAIN (t))
8085 c_write_global_declarations_2 (BLOCK_VARS (DECL_INITIAL (t)));
8086 c_write_global_declarations_2 (BLOCK_VARS (ext_block));
8087 timevar_pop (TV_SYMOUT);
8090 ext_block = NULL;
8093 #include "gt-c-decl.h"