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 2, or (at your option) any later
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
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
22 /* Process declarations and symbol lookup for C front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
31 #include "coretypes.h"
36 #include "tree-inline.h"
53 #include "langhooks.h"
54 #include "tree-mudflap.h"
55 #include "tree-gimple.h"
56 #include "diagnostic.h"
57 #include "tree-dump.h"
62 #include "langhooks-def.h"
63 #include "pointer-set.h"
65 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
67 { NORMAL, /* Ordinary declaration */
68 FUNCDEF, /* Function definition */
69 PARM, /* Declaration of parm before function body */
70 FIELD, /* Declaration inside struct or union */
71 TYPENAME}; /* Typename (inside cast or sizeof) */
74 /* Nonzero if we have seen an invalid cross reference
75 to a struct, union, or enum, but not yet printed the message. */
76 tree pending_invalid_xref;
78 /* File and line to appear in the eventual error message. */
79 location_t pending_invalid_xref_location;
81 /* True means we've initialized exception handling. */
82 bool c_eh_initialized_p;
84 /* While defining an enum type, this is 1 plus the last enumerator
85 constant value. Note that will do not have to save this or `enum_overflow'
86 around nested function definition since such a definition could only
87 occur in an enum value expression and we don't use these variables in
90 static tree enum_next_value;
92 /* Nonzero means that there was overflow computing enum_next_value. */
94 static int enum_overflow;
96 /* The file and line that the prototype came from if this is an
97 old-style definition; used for diagnostics in
98 store_parm_decls_oldstyle. */
100 static location_t current_function_prototype_locus;
102 /* Whether this prototype was built-in. */
104 static bool current_function_prototype_built_in;
106 /* The argument type information of this prototype. */
108 static tree current_function_prototype_arg_types;
110 /* The argument information structure for the function currently being
113 static struct c_arg_info *current_function_arg_info;
115 /* The obstack on which parser and related data structures, which are
116 not live beyond their top-level declaration or definition, are
118 struct obstack parser_obstack;
120 /* The current statement tree. */
122 static GTY(()) struct stmt_tree_s c_stmt_tree;
124 /* State saving variables. */
128 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
129 included in this invocation. Note that the current translation
130 unit is not included in this list. */
132 static GTY(()) tree all_translation_units;
134 /* A list of decls to be made automatically visible in each file scope. */
135 static GTY(()) tree visible_builtins;
137 /* Set to 0 at beginning of a function definition, set to 1 if
138 a return statement that specifies a return value is seen. */
140 int current_function_returns_value;
142 /* Set to 0 at beginning of a function definition, set to 1 if
143 a return statement with no argument is seen. */
145 int current_function_returns_null;
147 /* Set to 0 at beginning of a function definition, set to 1 if
148 a call to a noreturn function is seen. */
150 int current_function_returns_abnormally;
152 /* Set to nonzero by `grokdeclarator' for a function
153 whose return type is defaulted, if warnings for this are desired. */
155 static int warn_about_return_type;
157 /* Nonzero when the current toplevel function contains a declaration
158 of a nested function which is never defined. */
160 static bool undef_nested_function;
162 /* True means global_bindings_p should return false even if the scope stack
163 says we are in file scope. */
164 bool c_override_global_bindings_to_false;
167 /* Each c_binding structure describes one binding of an identifier to
168 a decl. All the decls in a scope - irrespective of namespace - are
169 chained together by the ->prev field, which (as the name implies)
170 runs in reverse order. All the decls in a given namespace bound to
171 a given identifier are chained by the ->shadowed field, which runs
172 from inner to outer scopes.
174 The ->decl field usually points to a DECL node, but there are two
175 exceptions. In the namespace of type tags, the bound entity is a
176 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
177 identifier is encountered, it is bound to error_mark_node to
178 suppress further errors about that identifier in the current
181 The ->type field stores the type of the declaration in this scope;
182 if NULL, the type is the type of the ->decl field. This is only of
183 relevance for objects with external or internal linkage which may
184 be redeclared in inner scopes, forming composite types that only
185 persist for the duration of those scopes. In the external scope,
186 this stores the composite of all the types declared for this
187 object, visible or not. The ->inner_comp field (used only at file
188 scope) stores whether an incomplete array type at file scope was
189 completed at an inner scope to an array size other than 1.
191 The depth field is copied from the scope structure that holds this
192 decl. It is used to preserve the proper ordering of the ->shadowed
193 field (see bind()) and also for a handful of special-case checks.
194 Finally, the invisible bit is true for a decl which should be
195 ignored for purposes of normal name lookup, and the nested bit is
196 true for a decl that's been bound a second time in an inner scope;
197 in all such cases, the binding in the outer scope will have its
198 invisible bit true. */
200 struct c_binding GTY((chain_next ("%h.prev")))
202 tree decl; /* the decl bound */
203 tree type; /* the type in this scope */
204 tree id; /* the identifier it's bound to */
205 struct c_binding *prev; /* the previous decl in this scope */
206 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
207 unsigned int depth : 28; /* depth of this scope */
208 BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
209 BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
210 BOOL_BITFIELD inner_comp : 1; /* incomplete array completed in inner scope */
213 #define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
214 #define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
215 #define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
216 #define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
218 #define I_SYMBOL_BINDING(node) \
219 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->symbol_binding)
220 #define I_SYMBOL_DECL(node) \
221 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
223 #define I_TAG_BINDING(node) \
224 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->tag_binding)
225 #define I_TAG_DECL(node) \
226 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
228 #define I_LABEL_BINDING(node) \
229 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->label_binding)
230 #define I_LABEL_DECL(node) \
231 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
233 /* Each C symbol points to three linked lists of c_binding structures.
234 These describe the values of the identifier in the three different
235 namespaces defined by the language. */
237 struct lang_identifier GTY(())
239 struct c_common_identifier common_id;
240 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
241 struct c_binding *tag_binding; /* struct/union/enum tags */
242 struct c_binding *label_binding; /* labels */
245 /* Validate c-lang.c's assumptions. */
246 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
247 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
249 /* The resulting tree type. */
252 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
253 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *) TYPE_NEXT_VARIANT (&%h.generic) : (GIMPLE_TUPLE_P (&%h.generic) ? (union lang_tree_node *) 0 : (union lang_tree_node *) TREE_CHAIN (&%h.generic))")))
255 union tree_node GTY ((tag ("0"),
256 desc ("tree_node_structure (&%h)")))
258 struct lang_identifier GTY ((tag ("1"))) identifier;
261 /* Each c_scope structure describes the complete contents of one
262 scope. Four scopes are distinguished specially: the innermost or
263 current scope, the innermost function scope, the file scope (always
264 the second to outermost) and the outermost or external scope.
266 Most declarations are recorded in the current scope.
268 All normal label declarations are recorded in the innermost
269 function scope, as are bindings of undeclared identifiers to
270 error_mark_node. (GCC permits nested functions as an extension,
271 hence the 'innermost' qualifier.) Explicitly declared labels
272 (using the __label__ extension) appear in the current scope.
274 Being in the file scope (current_scope == file_scope) causes
275 special behavior in several places below. Also, under some
276 conditions the Objective-C front end records declarations in the
277 file scope even though that isn't the current scope.
279 All declarations with external linkage are recorded in the external
280 scope, even if they aren't visible there; this models the fact that
281 such declarations are visible to the entire program, and (with a
282 bit of cleverness, see pushdecl) allows diagnosis of some violations
283 of C99 6.2.2p7 and 6.2.7p2:
285 If, within the same translation unit, the same identifier appears
286 with both internal and external linkage, the behavior is
289 All declarations that refer to the same object or function shall
290 have compatible type; otherwise, the behavior is undefined.
292 Initially only the built-in declarations, which describe compiler
293 intrinsic functions plus a subset of the standard library, are in
296 The order of the blocks list matters, and it is frequently appended
297 to. To avoid having to walk all the way to the end of the list on
298 each insertion, or reverse the list later, we maintain a pointer to
299 the last list entry. (FIXME: It should be feasible to use a reversed
302 The bindings list is strictly in reverse order of declarations;
303 pop_scope relies on this. */
306 struct c_scope GTY((chain_next ("%h.outer")))
308 /* The scope containing this one. */
309 struct c_scope *outer;
311 /* The next outermost function scope. */
312 struct c_scope *outer_function;
314 /* All bindings in this scope. */
315 struct c_binding *bindings;
317 /* For each scope (except the global one), a chain of BLOCK nodes
318 for all the scopes that were entered and exited one level down. */
322 /* The depth of this scope. Used to keep the ->shadowed chain of
323 bindings sorted innermost to outermost. */
324 unsigned int depth : 28;
326 /* True if we are currently filling this scope with parameter
328 BOOL_BITFIELD parm_flag : 1;
330 /* True if we saw [*] in this scope. Used to give an error messages
331 if these appears in a function definition. */
332 BOOL_BITFIELD had_vla_unspec : 1;
334 /* True if we already complained about forward parameter decls
335 in this scope. This prevents double warnings on
336 foo (int a; int b; ...) */
337 BOOL_BITFIELD warned_forward_parm_decls : 1;
339 /* True if this is the outermost block scope of a function body.
340 This scope contains the parameters, the local variables declared
341 in the outermost block, and all the labels (except those in
342 nested functions, or declared at block scope with __label__). */
343 BOOL_BITFIELD function_body : 1;
345 /* True means make a BLOCK for this scope no matter what. */
346 BOOL_BITFIELD keep : 1;
349 /* The scope currently in effect. */
351 static GTY(()) struct c_scope *current_scope;
353 /* The innermost function scope. Ordinary (not explicitly declared)
354 labels, bindings to error_mark_node, and the lazily-created
355 bindings of __func__ and its friends get this scope. */
357 static GTY(()) struct c_scope *current_function_scope;
359 /* The C file scope. This is reset for each input translation unit. */
361 static GTY(()) struct c_scope *file_scope;
363 /* The outermost scope. This is used for all declarations with
364 external linkage, and only these, hence the name. */
366 static GTY(()) struct c_scope *external_scope;
368 /* A chain of c_scope structures awaiting reuse. */
370 static GTY((deletable)) struct c_scope *scope_freelist;
372 /* A chain of c_binding structures awaiting reuse. */
374 static GTY((deletable)) struct c_binding *binding_freelist;
376 /* Append VAR to LIST in scope SCOPE. */
377 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
378 struct c_scope *s_ = (scope); \
380 if (s_->list##_last) \
381 TREE_CHAIN (s_->list##_last) = d_; \
384 s_->list##_last = d_; \
387 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
388 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
389 struct c_scope *t_ = (tscope); \
390 struct c_scope *f_ = (fscope); \
392 TREE_CHAIN (t_->to##_last) = f_->from; \
395 t_->to##_last = f_->from##_last; \
398 /* True means unconditionally make a BLOCK for the next scope pushed. */
400 static bool keep_next_level_flag;
402 /* True means the next call to push_scope will be the outermost scope
403 of a function body, so do not push a new scope, merely cease
404 expecting parameter decls. */
406 static bool next_is_function_body;
408 /* Forward declarations. */
409 static tree lookup_name_in_scope (tree, struct c_scope *);
410 static tree c_make_fname_decl (tree, int);
411 static tree grokdeclarator (const struct c_declarator *,
412 struct c_declspecs *,
413 enum decl_context, bool, tree *);
414 static tree grokparms (struct c_arg_info *, bool);
415 static void layout_array_type (tree);
417 /* T is a statement. Add it to the statement-tree. This is the
418 C/ObjC version--C++ has a slightly different version of this
424 enum tree_code code = TREE_CODE (t);
426 if (CAN_HAVE_LOCATION_P (t) && code != LABEL_EXPR)
428 if (!EXPR_HAS_LOCATION (t))
429 SET_EXPR_LOCATION (t, input_location);
432 if (code == LABEL_EXPR || code == CASE_LABEL_EXPR)
433 STATEMENT_LIST_HAS_LABEL (cur_stmt_list) = 1;
435 /* Add T to the statement-tree. Non-side-effect statements need to be
436 recorded during statement expressions. */
437 append_to_statement_list_force (t, &cur_stmt_list);
442 /* States indicating how grokdeclarator() should handle declspecs marked
443 with __attribute__((deprecated)). An object declared as
444 __attribute__((deprecated)) suppresses warnings of uses of other
447 enum deprecated_states {
452 static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
455 c_print_identifier (FILE *file, tree node, int indent)
457 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
458 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
459 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
460 if (C_IS_RESERVED_WORD (node))
462 tree rid = ridpointers[C_RID_CODE (node)];
463 indent_to (file, indent + 4);
464 fprintf (file, "rid %p \"%s\"",
465 (void *) rid, IDENTIFIER_POINTER (rid));
469 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
470 which may be any of several kinds of DECL or TYPE or error_mark_node,
471 in the scope SCOPE. */
473 bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
475 struct c_binding *b, **here;
477 if (binding_freelist)
479 b = binding_freelist;
480 binding_freelist = b->prev;
483 b = GGC_NEW (struct c_binding);
488 b->depth = scope->depth;
489 b->invisible = invisible;
495 b->prev = scope->bindings;
501 switch (TREE_CODE (decl))
503 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
506 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
512 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
518 /* Locate the appropriate place in the chain of shadowed decls
519 to insert this binding. Normally, scope == current_scope and
520 this does nothing. */
521 while (*here && (*here)->depth > scope->depth)
522 here = &(*here)->shadowed;
528 /* Clear the binding structure B, stick it on the binding_freelist,
529 and return the former value of b->prev. This is used by pop_scope
530 and get_parm_info to iterate destructively over all the bindings
531 from a given scope. */
532 static struct c_binding *
533 free_binding_and_advance (struct c_binding *b)
535 struct c_binding *prev = b->prev;
537 memset (b, 0, sizeof (struct c_binding));
538 b->prev = binding_freelist;
539 binding_freelist = b;
545 /* Hook called at end of compilation to assume 1 elt
546 for a file-scope tentative array defn that wasn't complete before. */
549 c_finish_incomplete_decl (tree decl)
551 if (TREE_CODE (decl) == VAR_DECL)
553 tree type = TREE_TYPE (decl);
554 if (type != error_mark_node
555 && TREE_CODE (type) == ARRAY_TYPE
556 && !DECL_EXTERNAL (decl)
557 && TYPE_DOMAIN (type) == 0)
559 warning (0, "array %q+D assumed to have one element", decl);
561 complete_array_type (&TREE_TYPE (decl), NULL_TREE, true);
563 layout_decl (decl, 0);
568 /* The Objective-C front-end often needs to determine the current scope. */
571 objc_get_current_scope (void)
573 return current_scope;
576 /* The following function is used only by Objective-C. It needs to live here
577 because it accesses the innards of c_scope. */
580 objc_mark_locals_volatile (void *enclosing_blk)
582 struct c_scope *scope;
585 for (scope = current_scope;
586 scope && scope != enclosing_blk;
587 scope = scope->outer)
589 for (b = scope->bindings; b; b = b->prev)
590 objc_volatilize_decl (b->decl);
592 /* Do not climb up past the current function. */
593 if (scope->function_body)
598 /* Nonzero if we are currently in file scope. */
601 global_bindings_p (void)
603 return current_scope == file_scope && !c_override_global_bindings_to_false;
607 keep_next_level (void)
609 keep_next_level_flag = true;
612 /* Identify this scope as currently being filled with parameters. */
615 declare_parm_level (void)
617 current_scope->parm_flag = true;
623 if (next_is_function_body)
625 /* This is the transition from the parameters to the top level
626 of the function body. These are the same scope
627 (C99 6.2.1p4,6) so we do not push another scope structure.
628 next_is_function_body is set only by store_parm_decls, which
629 in turn is called when and only when we are about to
630 encounter the opening curly brace for the function body.
632 The outermost block of a function always gets a BLOCK node,
633 because the debugging output routines expect that each
634 function has at least one BLOCK. */
635 current_scope->parm_flag = false;
636 current_scope->function_body = true;
637 current_scope->keep = true;
638 current_scope->outer_function = current_function_scope;
639 current_function_scope = current_scope;
641 keep_next_level_flag = false;
642 next_is_function_body = false;
646 struct c_scope *scope;
649 scope = scope_freelist;
650 scope_freelist = scope->outer;
653 scope = GGC_CNEW (struct c_scope);
655 scope->keep = keep_next_level_flag;
656 scope->outer = current_scope;
657 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
659 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
661 if (current_scope && scope->depth == 0)
664 sorry ("GCC supports only %u nested scopes", scope->depth);
667 current_scope = scope;
668 keep_next_level_flag = false;
672 /* Set the TYPE_CONTEXT of all of TYPE's variants to CONTEXT. */
675 set_type_context (tree type, tree context)
677 for (type = TYPE_MAIN_VARIANT (type); type;
678 type = TYPE_NEXT_VARIANT (type))
679 TYPE_CONTEXT (type) = context;
682 /* Exit a scope. Restore the state of the identifier-decl mappings
683 that were in effect when this scope was entered. Return a BLOCK
684 node containing all the DECLs in this scope that are of interest
685 to debug info generation. */
690 struct c_scope *scope = current_scope;
691 tree block, context, p;
694 bool functionbody = scope->function_body;
695 bool keep = functionbody || scope->keep || scope->bindings;
697 c_end_vm_scope (scope->depth);
699 /* If appropriate, create a BLOCK to record the decls for the life
704 block = make_node (BLOCK);
705 BLOCK_SUBBLOCKS (block) = scope->blocks;
706 TREE_USED (block) = 1;
708 /* In each subblock, record that this is its superior. */
709 for (p = scope->blocks; p; p = TREE_CHAIN (p))
710 BLOCK_SUPERCONTEXT (p) = block;
712 BLOCK_VARS (block) = 0;
715 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
716 scope must be set so that they point to the appropriate
717 construct, i.e. either to the current FUNCTION_DECL node, or
718 else to the BLOCK node we just constructed.
720 Note that for tagged types whose scope is just the formal
721 parameter list for some function type specification, we can't
722 properly set their TYPE_CONTEXTs here, because we don't have a
723 pointer to the appropriate FUNCTION_TYPE node readily available
724 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
725 type nodes get set in `grokdeclarator' as soon as we have created
726 the FUNCTION_TYPE node which will represent the "scope" for these
727 "parameter list local" tagged types. */
728 if (scope->function_body)
729 context = current_function_decl;
730 else if (scope == file_scope)
732 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
733 TREE_CHAIN (file_decl) = all_translation_units;
734 all_translation_units = file_decl;
740 /* Clear all bindings in this scope. */
741 for (b = scope->bindings; b; b = free_binding_and_advance (b))
744 switch (TREE_CODE (p))
747 /* Warnings for unused labels, errors for undefined labels. */
748 if (TREE_USED (p) && !DECL_INITIAL (p))
750 error ("label %q+D used but not defined", p);
751 DECL_INITIAL (p) = error_mark_node;
754 warn_for_unused_label (p);
756 /* Labels go in BLOCK_VARS. */
757 TREE_CHAIN (p) = BLOCK_VARS (block);
758 BLOCK_VARS (block) = p;
759 gcc_assert (I_LABEL_BINDING (b->id) == b);
760 I_LABEL_BINDING (b->id) = b->shadowed;
766 set_type_context (p, context);
768 /* Types may not have tag-names, in which case the type
769 appears in the bindings list with b->id NULL. */
772 gcc_assert (I_TAG_BINDING (b->id) == b);
773 I_TAG_BINDING (b->id) = b->shadowed;
778 /* Propagate TREE_ADDRESSABLE from nested functions to their
779 containing functions. */
780 if (!TREE_ASM_WRITTEN (p)
781 && DECL_INITIAL (p) != 0
782 && TREE_ADDRESSABLE (p)
783 && DECL_ABSTRACT_ORIGIN (p) != 0
784 && DECL_ABSTRACT_ORIGIN (p) != p)
785 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
786 if (!DECL_EXTERNAL (p)
788 && scope != file_scope
789 && scope != external_scope)
791 error ("nested function %q+D declared but never defined", p);
792 undef_nested_function = true;
794 /* C99 6.7.4p6: "a function with external linkage... declared
795 with an inline function specifier ... shall also be defined in the
796 same translation unit." */
797 else if (DECL_DECLARED_INLINE_P (p)
800 && !flag_gnu89_inline)
801 pedwarn ("inline function %q+D declared but never defined", p);
806 /* Warnings for unused variables. */
808 && !TREE_NO_WARNING (p)
809 && !DECL_IN_SYSTEM_HEADER (p)
811 && !DECL_ARTIFICIAL (p)
812 && scope != file_scope
813 && scope != external_scope)
814 warning (OPT_Wunused_variable, "unused variable %q+D", p);
818 error ("type of array %q+D completed incompatibly with"
819 " implicit initialization", p);
826 /* All of these go in BLOCK_VARS, but only if this is the
827 binding in the home scope. */
830 TREE_CHAIN (p) = BLOCK_VARS (block);
831 BLOCK_VARS (block) = p;
833 /* If this is the file scope, and we are processing more
834 than one translation unit in this compilation, set
835 DECL_CONTEXT of each decl to the TRANSLATION_UNIT_DECL.
836 This makes same_translation_unit_p work, and causes
837 static declarations to be given disambiguating suffixes. */
838 if (scope == file_scope && num_in_fnames > 1)
840 DECL_CONTEXT (p) = context;
841 if (TREE_CODE (p) == TYPE_DECL)
842 set_type_context (TREE_TYPE (p), context);
846 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
847 already been put there by store_parm_decls. Unused-
848 parameter warnings are handled by function.c.
849 error_mark_node obviously does not go in BLOCK_VARS and
850 does not get unused-variable warnings. */
853 /* It is possible for a decl not to have a name. We get
854 here with b->id NULL in this case. */
857 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
858 I_SYMBOL_BINDING (b->id) = b->shadowed;
859 if (b->shadowed && b->shadowed->type)
860 TREE_TYPE (b->shadowed->decl) = b->shadowed->type;
870 /* Dispose of the block that we just made inside some higher level. */
871 if ((scope->function_body || scope == file_scope) && context)
873 DECL_INITIAL (context) = block;
874 BLOCK_SUPERCONTEXT (block) = context;
876 else if (scope->outer)
879 SCOPE_LIST_APPEND (scope->outer, blocks, block);
880 /* If we did not make a block for the scope just exited, any
881 blocks made for inner scopes must be carried forward so they
882 will later become subblocks of something else. */
883 else if (scope->blocks)
884 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
887 /* Pop the current scope, and free the structure for reuse. */
888 current_scope = scope->outer;
889 if (scope->function_body)
890 current_function_scope = scope->outer_function;
892 memset (scope, 0, sizeof (struct c_scope));
893 scope->outer = scope_freelist;
894 scope_freelist = scope;
900 push_file_scope (void)
908 file_scope = current_scope;
910 start_fname_decls ();
912 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
913 bind (DECL_NAME (decl), decl, file_scope,
914 /*invisible=*/false, /*nested=*/true);
918 pop_file_scope (void)
920 /* In case there were missing closebraces, get us back to the global
922 while (current_scope != file_scope)
925 /* __FUNCTION__ is defined at file scope (""). This
926 call may not be necessary as my tests indicate it
927 still works without it. */
928 finish_fname_decls ();
930 /* This is the point to write out a PCH if we're doing that.
931 In that case we do not want to do anything else. */
934 c_common_write_pch ();
938 /* Pop off the file scope and close this translation unit. */
942 maybe_apply_pending_pragma_weaks ();
943 cgraph_finalize_compilation_unit ();
946 /* Insert BLOCK at the end of the list of subblocks of the current
947 scope. This is used when a BIND_EXPR is expanded, to handle the
948 BLOCK node inside the BIND_EXPR. */
951 insert_block (tree block)
953 TREE_USED (block) = 1;
954 SCOPE_LIST_APPEND (current_scope, blocks, block);
957 /* Push a definition or a declaration of struct, union or enum tag "name".
958 "type" should be the type node.
959 We assume that the tag "name" is not already defined.
961 Note that the definition may really be just a forward reference.
962 In that case, the TYPE_SIZE will be zero. */
965 pushtag (tree name, tree type)
967 /* Record the identifier as the type's name if it has none. */
968 if (name && !TYPE_NAME (type))
969 TYPE_NAME (type) = name;
970 bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
972 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
973 tagged type we just added to the current scope. This fake
974 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
975 to output a representation of a tagged type, and it also gives
976 us a convenient place to record the "scope start" address for the
979 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
981 /* An approximation for now, so we can tell this is a function-scope tag.
982 This will be updated in pop_scope. */
983 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
986 /* Subroutine of compare_decls. Allow harmless mismatches in return
987 and argument types provided that the type modes match. This function
988 return a unified type given a suitable match, and 0 otherwise. */
991 match_builtin_function_types (tree newtype, tree oldtype)
993 tree newrettype, oldrettype;
994 tree newargs, oldargs;
995 tree trytype, tryargs;
997 /* Accept the return type of the new declaration if same modes. */
998 oldrettype = TREE_TYPE (oldtype);
999 newrettype = TREE_TYPE (newtype);
1001 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
1004 oldargs = TYPE_ARG_TYPES (oldtype);
1005 newargs = TYPE_ARG_TYPES (newtype);
1008 while (oldargs || newargs)
1012 || !TREE_VALUE (oldargs)
1013 || !TREE_VALUE (newargs)
1014 || TYPE_MODE (TREE_VALUE (oldargs))
1015 != TYPE_MODE (TREE_VALUE (newargs)))
1018 oldargs = TREE_CHAIN (oldargs);
1019 newargs = TREE_CHAIN (newargs);
1022 trytype = build_function_type (newrettype, tryargs);
1023 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
1026 /* Subroutine of diagnose_mismatched_decls. Check for function type
1027 mismatch involving an empty arglist vs a nonempty one and give clearer
1030 diagnose_arglist_conflict (tree newdecl, tree olddecl,
1031 tree newtype, tree oldtype)
1035 if (TREE_CODE (olddecl) != FUNCTION_DECL
1036 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
1037 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
1039 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
1042 t = TYPE_ARG_TYPES (oldtype);
1044 t = TYPE_ARG_TYPES (newtype);
1045 for (; t; t = TREE_CHAIN (t))
1047 tree type = TREE_VALUE (t);
1049 if (TREE_CHAIN (t) == 0
1050 && TYPE_MAIN_VARIANT (type) != void_type_node)
1052 inform ("a parameter list with an ellipsis can%'t match "
1053 "an empty parameter name list declaration");
1057 if (c_type_promotes_to (type) != type)
1059 inform ("an argument type that has a default promotion can%'t match "
1060 "an empty parameter name list declaration");
1066 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
1067 old-style function definition, NEWDECL is a prototype declaration.
1068 Diagnose inconsistencies in the argument list. Returns TRUE if
1069 the prototype is compatible, FALSE if not. */
1071 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
1073 tree newargs, oldargs;
1076 #define END_OF_ARGLIST(t) ((t) == void_type_node)
1078 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
1079 newargs = TYPE_ARG_TYPES (newtype);
1084 tree oldargtype = TREE_VALUE (oldargs);
1085 tree newargtype = TREE_VALUE (newargs);
1087 if (oldargtype == error_mark_node || newargtype == error_mark_node)
1090 oldargtype = TYPE_MAIN_VARIANT (oldargtype);
1091 newargtype = TYPE_MAIN_VARIANT (newargtype);
1093 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
1096 /* Reaching the end of just one list means the two decls don't
1097 agree on the number of arguments. */
1098 if (END_OF_ARGLIST (oldargtype))
1100 error ("prototype for %q+D declares more arguments "
1101 "than previous old-style definition", newdecl);
1104 else if (END_OF_ARGLIST (newargtype))
1106 error ("prototype for %q+D declares fewer arguments "
1107 "than previous old-style definition", newdecl);
1111 /* Type for passing arg must be consistent with that declared
1113 else if (!comptypes (oldargtype, newargtype))
1115 error ("prototype for %q+D declares argument %d"
1116 " with incompatible type",
1121 oldargs = TREE_CHAIN (oldargs);
1122 newargs = TREE_CHAIN (newargs);
1126 /* If we get here, no errors were found, but do issue a warning
1127 for this poor-style construct. */
1128 warning (0, "prototype for %q+D follows non-prototype definition",
1131 #undef END_OF_ARGLIST
1134 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1135 first in a pair of mismatched declarations, using the diagnostic
1138 locate_old_decl (tree decl, void (*diag)(const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2))
1140 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1142 else if (DECL_INITIAL (decl))
1143 diag (G_("previous definition of %q+D was here"), decl);
1144 else if (C_DECL_IMPLICIT (decl))
1145 diag (G_("previous implicit declaration of %q+D was here"), decl);
1147 diag (G_("previous declaration of %q+D was here"), decl);
1150 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1151 Returns true if the caller should proceed to merge the two, false
1152 if OLDDECL should simply be discarded. As a side effect, issues
1153 all necessary diagnostics for invalid or poor-style combinations.
1154 If it returns true, writes the types of NEWDECL and OLDDECL to
1155 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1156 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1159 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1160 tree *newtypep, tree *oldtypep)
1162 tree newtype, oldtype;
1163 bool pedwarned = false;
1164 bool warned = false;
1167 #define DECL_EXTERN_INLINE(DECL) (DECL_DECLARED_INLINE_P (DECL) \
1168 && DECL_EXTERNAL (DECL))
1170 /* If we have error_mark_node for either decl or type, just discard
1171 the previous decl - we're in an error cascade already. */
1172 if (olddecl == error_mark_node || newdecl == error_mark_node)
1174 *oldtypep = oldtype = TREE_TYPE (olddecl);
1175 *newtypep = newtype = TREE_TYPE (newdecl);
1176 if (oldtype == error_mark_node || newtype == error_mark_node)
1179 /* Two different categories of symbol altogether. This is an error
1180 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1181 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1183 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1184 && DECL_BUILT_IN (olddecl)
1185 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1187 error ("%q+D redeclared as different kind of symbol", newdecl);
1188 locate_old_decl (olddecl, error);
1190 else if (TREE_PUBLIC (newdecl))
1191 warning (0, "built-in function %q+D declared as non-function",
1194 warning (OPT_Wshadow, "declaration of %q+D shadows "
1195 "a built-in function", newdecl);
1199 /* Enumerators have no linkage, so may only be declared once in a
1201 if (TREE_CODE (olddecl) == CONST_DECL)
1203 error ("redeclaration of enumerator %q+D", newdecl);
1204 locate_old_decl (olddecl, error);
1208 if (!comptypes (oldtype, newtype))
1210 if (TREE_CODE (olddecl) == FUNCTION_DECL
1211 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1213 /* Accept harmless mismatch in function types.
1214 This is for the ffs and fprintf builtins. */
1215 tree trytype = match_builtin_function_types (newtype, oldtype);
1217 if (trytype && comptypes (newtype, trytype))
1218 *oldtypep = oldtype = trytype;
1221 /* If types don't match for a built-in, throw away the
1222 built-in. No point in calling locate_old_decl here, it
1223 won't print anything. */
1224 warning (0, "conflicting types for built-in function %q+D",
1229 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1230 && DECL_IS_BUILTIN (olddecl))
1232 /* A conflicting function declaration for a predeclared
1233 function that isn't actually built in. Objective C uses
1234 these. The new declaration silently overrides everything
1235 but the volatility (i.e. noreturn) indication. See also
1236 below. FIXME: Make Objective C use normal builtins. */
1237 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1240 /* Permit void foo (...) to match int foo (...) if the latter is
1241 the definition and implicit int was used. See
1242 c-torture/compile/920625-2.c. */
1243 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1244 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1245 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1246 && C_FUNCTION_IMPLICIT_INT (newdecl) && !DECL_INITIAL (olddecl))
1248 pedwarn ("conflicting types for %q+D", newdecl);
1249 /* Make sure we keep void as the return type. */
1250 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1251 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1254 /* Permit void foo (...) to match an earlier call to foo (...) with
1255 no declared type (thus, implicitly int). */
1256 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1257 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == void_type_node
1258 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == integer_type_node
1259 && C_DECL_IMPLICIT (olddecl) && !DECL_INITIAL (olddecl))
1261 pedwarn ("conflicting types for %q+D", newdecl);
1262 /* Make sure we keep void as the return type. */
1263 TREE_TYPE (olddecl) = *oldtypep = oldtype = newtype;
1268 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1269 error ("conflicting type qualifiers for %q+D", newdecl);
1271 error ("conflicting types for %q+D", newdecl);
1272 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1273 locate_old_decl (olddecl, error);
1278 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1279 but silently ignore the redeclaration if either is in a system
1280 header. (Conflicting redeclarations were handled above.) */
1281 if (TREE_CODE (newdecl) == TYPE_DECL)
1283 if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
1284 return true; /* Allow OLDDECL to continue in use. */
1286 error ("redefinition of typedef %q+D", newdecl);
1287 locate_old_decl (olddecl, error);
1291 /* Function declarations can either be 'static' or 'extern' (no
1292 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1293 can never conflict with each other on account of linkage
1294 (6.2.2p4). Multiple definitions are not allowed (6.9p3,5) but
1295 gnu89 mode permits two definitions if one is 'extern inline' and
1296 one is not. The non- extern-inline definition supersedes the
1297 extern-inline definition. */
1299 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1301 /* If you declare a built-in function name as static, or
1302 define the built-in with an old-style definition (so we
1303 can't validate the argument list) the built-in definition is
1304 overridden, but optionally warn this was a bad choice of name. */
1305 if (DECL_BUILT_IN (olddecl)
1306 && !C_DECL_DECLARED_BUILTIN (olddecl)
1307 && (!TREE_PUBLIC (newdecl)
1308 || (DECL_INITIAL (newdecl)
1309 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1311 warning (OPT_Wshadow, "declaration of %q+D shadows "
1312 "a built-in function", newdecl);
1313 /* Discard the old built-in function. */
1317 if (DECL_INITIAL (newdecl))
1319 if (DECL_INITIAL (olddecl))
1321 /* If both decls are in the same TU and the new declaration
1322 isn't overriding an extern inline reject the new decl.
1323 In c99, no overriding is allowed in the same translation
1325 if ((!DECL_EXTERN_INLINE (olddecl)
1326 || DECL_EXTERN_INLINE (newdecl)
1327 || (!flag_gnu89_inline
1328 && (!DECL_DECLARED_INLINE_P (olddecl)
1329 || !lookup_attribute ("gnu_inline",
1330 DECL_ATTRIBUTES (olddecl)))
1331 && (!DECL_DECLARED_INLINE_P (newdecl)
1332 || !lookup_attribute ("gnu_inline",
1333 DECL_ATTRIBUTES (newdecl))))
1335 && same_translation_unit_p (newdecl, olddecl))
1337 error ("redefinition of %q+D", newdecl);
1338 locate_old_decl (olddecl, error);
1343 /* If we have a prototype after an old-style function definition,
1344 the argument types must be checked specially. */
1345 else if (DECL_INITIAL (olddecl)
1346 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1347 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1348 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1350 locate_old_decl (olddecl, error);
1353 /* A non-static declaration (even an "extern") followed by a
1354 static declaration is undefined behavior per C99 6.2.2p3-5,7.
1355 The same is true for a static forward declaration at block
1356 scope followed by a non-static declaration/definition at file
1357 scope. Static followed by non-static at the same scope is
1358 not undefined behavior, and is the most convenient way to get
1359 some effects (see e.g. what unwind-dw2-fde-glibc.c does to
1360 the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
1361 we do diagnose it if -Wtraditional. */
1362 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1364 /* Two exceptions to the rule. If olddecl is an extern
1365 inline, or a predeclared function that isn't actually
1366 built in, newdecl silently overrides olddecl. The latter
1367 occur only in Objective C; see also above. (FIXME: Make
1368 Objective C use normal builtins.) */
1369 if (!DECL_IS_BUILTIN (olddecl)
1370 && !DECL_EXTERN_INLINE (olddecl))
1372 error ("static declaration of %q+D follows "
1373 "non-static declaration", newdecl);
1374 locate_old_decl (olddecl, error);
1378 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
1380 if (DECL_CONTEXT (olddecl))
1382 error ("non-static declaration of %q+D follows "
1383 "static declaration", newdecl);
1384 locate_old_decl (olddecl, error);
1387 else if (warn_traditional)
1389 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1390 "follows static declaration", newdecl);
1395 /* Make sure gnu_inline attribute is either not present, or
1396 present on all inline decls. */
1397 if (DECL_DECLARED_INLINE_P (olddecl)
1398 && DECL_DECLARED_INLINE_P (newdecl))
1400 bool newa = lookup_attribute ("gnu_inline",
1401 DECL_ATTRIBUTES (newdecl)) != NULL;
1402 bool olda = lookup_attribute ("gnu_inline",
1403 DECL_ATTRIBUTES (olddecl)) != NULL;
1406 error ("%<gnu_inline%> attribute present on %q+D",
1407 newa ? newdecl : olddecl);
1408 error ("%Jbut not here", newa ? olddecl : newdecl);
1412 else if (TREE_CODE (newdecl) == VAR_DECL)
1414 /* Only variables can be thread-local, and all declarations must
1415 agree on this property. */
1416 if (C_DECL_THREADPRIVATE_P (olddecl) && !DECL_THREAD_LOCAL_P (newdecl))
1418 /* Nothing to check. Since OLDDECL is marked threadprivate
1419 and NEWDECL does not have a thread-local attribute, we
1420 will merge the threadprivate attribute into NEWDECL. */
1423 else if (DECL_THREAD_LOCAL_P (newdecl) != DECL_THREAD_LOCAL_P (olddecl))
1425 if (DECL_THREAD_LOCAL_P (newdecl))
1426 error ("thread-local declaration of %q+D follows "
1427 "non-thread-local declaration", newdecl);
1429 error ("non-thread-local declaration of %q+D follows "
1430 "thread-local declaration", newdecl);
1432 locate_old_decl (olddecl, error);
1436 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1437 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1439 error ("redefinition of %q+D", newdecl);
1440 locate_old_decl (olddecl, error);
1444 /* Objects declared at file scope: if the first declaration had
1445 external linkage (even if it was an external reference) the
1446 second must have external linkage as well, or the behavior is
1447 undefined. If the first declaration had internal linkage, then
1448 the second must too, or else be an external reference (in which
1449 case the composite declaration still has internal linkage).
1450 As for function declarations, we warn about the static-then-
1451 extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
1452 if (DECL_FILE_SCOPE_P (newdecl)
1453 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1455 if (DECL_EXTERNAL (newdecl))
1457 if (!DECL_FILE_SCOPE_P (olddecl))
1459 error ("extern declaration of %q+D follows "
1460 "declaration with no linkage", newdecl);
1461 locate_old_decl (olddecl, error);
1464 else if (warn_traditional)
1466 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1467 "follows static declaration", newdecl);
1473 if (TREE_PUBLIC (newdecl))
1474 error ("non-static declaration of %q+D follows "
1475 "static declaration", newdecl);
1477 error ("static declaration of %q+D follows "
1478 "non-static declaration", newdecl);
1480 locate_old_decl (olddecl, error);
1484 /* Two objects with the same name declared at the same block
1485 scope must both be external references (6.7p3). */
1486 else if (!DECL_FILE_SCOPE_P (newdecl))
1488 if (DECL_EXTERNAL (newdecl))
1490 /* Extern with initializer at block scope, which will
1491 already have received an error. */
1493 else if (DECL_EXTERNAL (olddecl))
1495 error ("declaration of %q+D with no linkage follows "
1496 "extern declaration", newdecl);
1497 locate_old_decl (olddecl, error);
1501 error ("redeclaration of %q+D with no linkage", newdecl);
1502 locate_old_decl (olddecl, error);
1510 /* All decls must agree on a visibility. */
1511 if (CODE_CONTAINS_STRUCT (TREE_CODE (newdecl), TS_DECL_WITH_VIS)
1512 && DECL_VISIBILITY_SPECIFIED (newdecl) && DECL_VISIBILITY_SPECIFIED (olddecl)
1513 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1515 warning (0, "redeclaration of %q+D with different visibility "
1516 "(old visibility preserved)", newdecl);
1520 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1522 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1523 if (DECL_DECLARED_INLINE_P (newdecl)
1524 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1526 warning (OPT_Wattributes, "inline declaration of %qD follows "
1527 "declaration with attribute noinline", newdecl);
1530 else if (DECL_DECLARED_INLINE_P (olddecl)
1531 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1533 warning (OPT_Wattributes, "declaration of %q+D with attribute "
1534 "noinline follows inline declaration ", newdecl);
1538 /* Inline declaration after use or definition.
1539 ??? Should we still warn about this now we have unit-at-a-time
1540 mode and can get it right?
1541 Definitely don't complain if the decls are in different translation
1543 C99 permits this, so don't warn in that case. (The function
1544 may not be inlined everywhere in function-at-a-time mode, but
1545 we still shouldn't warn.) */
1546 if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl)
1547 && same_translation_unit_p (olddecl, newdecl)
1548 && flag_gnu89_inline)
1550 if (TREE_USED (olddecl))
1552 warning (0, "%q+D declared inline after being called", olddecl);
1555 else if (DECL_INITIAL (olddecl))
1557 warning (0, "%q+D declared inline after its definition", olddecl);
1562 else /* PARM_DECL, VAR_DECL */
1564 /* Redeclaration of a parameter is a constraint violation (this is
1565 not explicitly stated, but follows from C99 6.7p3 [no more than
1566 one declaration of the same identifier with no linkage in the
1567 same scope, except type tags] and 6.2.2p6 [parameters have no
1568 linkage]). We must check for a forward parameter declaration,
1569 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1570 an extension, the mandatory diagnostic for which is handled by
1571 mark_forward_parm_decls. */
1573 if (TREE_CODE (newdecl) == PARM_DECL
1574 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1576 error ("redefinition of parameter %q+D", newdecl);
1577 locate_old_decl (olddecl, error);
1582 /* Optional warning for completely redundant decls. */
1583 if (!warned && !pedwarned
1584 && warn_redundant_decls
1585 /* Don't warn about a function declaration followed by a
1587 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1588 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1589 /* Don't warn about redundant redeclarations of builtins. */
1590 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1591 && !DECL_BUILT_IN (newdecl)
1592 && DECL_BUILT_IN (olddecl)
1593 && !C_DECL_DECLARED_BUILTIN (olddecl))
1594 /* Don't warn about an extern followed by a definition. */
1595 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1596 /* Don't warn about forward parameter decls. */
1597 && !(TREE_CODE (newdecl) == PARM_DECL
1598 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1599 /* Don't warn about a variable definition following a declaration. */
1600 && !(TREE_CODE (newdecl) == VAR_DECL
1601 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl)))
1603 warning (OPT_Wredundant_decls, "redundant redeclaration of %q+D",
1608 /* Report location of previous decl/defn in a consistent manner. */
1609 if (warned || pedwarned)
1610 locate_old_decl (olddecl, pedwarned ? pedwarn : warning0);
1612 #undef DECL_EXTERN_INLINE
1617 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1618 consistent with OLDDECL, but carries new information. Merge the
1619 new information into OLDDECL. This function issues no
1623 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1625 bool new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1626 && DECL_INITIAL (newdecl) != 0);
1627 bool new_is_prototype = (TREE_CODE (newdecl) == FUNCTION_DECL
1628 && TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0);
1629 bool old_is_prototype = (TREE_CODE (olddecl) == FUNCTION_DECL
1630 && TYPE_ARG_TYPES (TREE_TYPE (olddecl)) != 0);
1631 bool extern_changed = false;
1633 /* For real parm decl following a forward decl, rechain the old decl
1634 in its new location and clear TREE_ASM_WRITTEN (it's not a
1635 forward decl anymore). */
1636 if (TREE_CODE (newdecl) == PARM_DECL
1637 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1639 struct c_binding *b, **here;
1641 for (here = ¤t_scope->bindings; *here; here = &(*here)->prev)
1642 if ((*here)->decl == olddecl)
1649 b->prev = current_scope->bindings;
1650 current_scope->bindings = b;
1652 TREE_ASM_WRITTEN (olddecl) = 0;
1655 DECL_ATTRIBUTES (newdecl)
1656 = targetm.merge_decl_attributes (olddecl, newdecl);
1658 /* Merge the data types specified in the two decls. */
1660 = TREE_TYPE (olddecl)
1661 = composite_type (newtype, oldtype);
1663 /* Lay the type out, unless already done. */
1664 if (!comptypes (oldtype, TREE_TYPE (newdecl)))
1666 if (TREE_TYPE (newdecl) != error_mark_node)
1667 layout_type (TREE_TYPE (newdecl));
1668 if (TREE_CODE (newdecl) != FUNCTION_DECL
1669 && TREE_CODE (newdecl) != TYPE_DECL
1670 && TREE_CODE (newdecl) != CONST_DECL)
1671 layout_decl (newdecl, 0);
1675 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1676 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1677 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1678 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1679 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1680 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1682 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1683 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1688 /* Merge the type qualifiers. */
1689 if (TREE_READONLY (newdecl))
1690 TREE_READONLY (olddecl) = 1;
1692 if (TREE_THIS_VOLATILE (newdecl))
1694 TREE_THIS_VOLATILE (olddecl) = 1;
1695 if (TREE_CODE (newdecl) == VAR_DECL)
1696 make_var_volatile (newdecl);
1699 /* Merge deprecatedness. */
1700 if (TREE_DEPRECATED (newdecl))
1701 TREE_DEPRECATED (olddecl) = 1;
1703 /* Keep source location of definition rather than declaration and of
1704 prototype rather than non-prototype unless that prototype is
1706 if ((DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1707 || (old_is_prototype && !new_is_prototype
1708 && !C_DECL_BUILTIN_PROTOTYPE (olddecl)))
1709 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1711 /* Merge the initialization information. */
1712 if (DECL_INITIAL (newdecl) == 0)
1713 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1715 /* Merge the threadprivate attribute. */
1716 if (TREE_CODE (olddecl) == VAR_DECL && C_DECL_THREADPRIVATE_P (olddecl))
1718 DECL_TLS_MODEL (newdecl) = DECL_TLS_MODEL (olddecl);
1719 C_DECL_THREADPRIVATE_P (newdecl) = 1;
1722 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS))
1724 /* Merge the unused-warning information. */
1725 if (DECL_IN_SYSTEM_HEADER (olddecl))
1726 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1727 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1728 DECL_IN_SYSTEM_HEADER (olddecl) = 1;
1730 /* Merge the section attribute.
1731 We want to issue an error if the sections conflict but that
1732 must be done later in decl_attributes since we are called
1733 before attributes are assigned. */
1734 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1735 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1737 /* Copy the assembler name.
1738 Currently, it can only be defined in the prototype. */
1739 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1741 /* Use visibility of whichever declaration had it specified */
1742 if (DECL_VISIBILITY_SPECIFIED (olddecl))
1744 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1745 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
1748 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1750 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1751 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1752 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1753 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1754 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1755 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1756 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1757 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1758 DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
1759 DECL_IS_NOVOPS (newdecl) |= DECL_IS_NOVOPS (olddecl);
1762 /* Merge the storage class information. */
1763 merge_weak (newdecl, olddecl);
1765 /* For functions, static overrides non-static. */
1766 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1768 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1769 /* This is since we don't automatically
1770 copy the attributes of NEWDECL into OLDDECL. */
1771 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1772 /* If this clears `static', clear it in the identifier too. */
1773 if (!TREE_PUBLIC (olddecl))
1774 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1778 /* In c99, 'extern' declaration before (or after) 'inline' means this
1779 function is not DECL_EXTERNAL, unless 'gnu_inline' attribute
1781 if (TREE_CODE (newdecl) == FUNCTION_DECL
1782 && !flag_gnu89_inline
1783 && (DECL_DECLARED_INLINE_P (newdecl)
1784 || DECL_DECLARED_INLINE_P (olddecl))
1785 && (!DECL_DECLARED_INLINE_P (newdecl)
1786 || !DECL_DECLARED_INLINE_P (olddecl)
1787 || !DECL_EXTERNAL (olddecl))
1788 && DECL_EXTERNAL (newdecl)
1789 && !lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (newdecl)))
1790 DECL_EXTERNAL (newdecl) = 0;
1792 if (DECL_EXTERNAL (newdecl))
1794 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1795 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1797 /* An extern decl does not override previous storage class. */
1798 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1799 if (!DECL_EXTERNAL (newdecl))
1801 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1802 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1807 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1808 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1811 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1813 /* If we're redefining a function previously defined as extern
1814 inline, make sure we emit debug info for the inline before we
1815 throw it away, in case it was inlined into a function that
1816 hasn't been written out yet. */
1817 if (new_is_definition && DECL_INITIAL (olddecl))
1819 if (TREE_USED (olddecl)
1820 /* In unit-at-a-time mode we never inline re-defined extern
1821 inline functions. */
1822 && !flag_unit_at_a_time
1823 && cgraph_function_possibly_inlined_p (olddecl))
1824 (*debug_hooks->outlining_inline_function) (olddecl);
1826 /* The new defn must not be inline. */
1827 DECL_INLINE (newdecl) = 0;
1828 DECL_UNINLINABLE (newdecl) = 1;
1832 /* If either decl says `inline', this fn is inline, unless
1833 its definition was passed already. */
1834 if (DECL_DECLARED_INLINE_P (newdecl)
1835 || DECL_DECLARED_INLINE_P (olddecl))
1836 DECL_DECLARED_INLINE_P (newdecl) = 1;
1838 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1839 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1842 if (DECL_BUILT_IN (olddecl))
1844 /* If redeclaring a builtin function, it stays built in.
1845 But it gets tagged as having been declared. */
1846 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1847 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1848 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1849 if (new_is_prototype)
1850 C_DECL_BUILTIN_PROTOTYPE (newdecl) = 0;
1852 C_DECL_BUILTIN_PROTOTYPE (newdecl)
1853 = C_DECL_BUILTIN_PROTOTYPE (olddecl);
1856 /* Also preserve various other info from the definition. */
1857 if (!new_is_definition)
1859 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1860 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1861 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1862 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1863 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1865 /* Set DECL_INLINE on the declaration if we've got a body
1866 from which to instantiate. */
1867 if (DECL_INLINE (olddecl) && !DECL_UNINLINABLE (newdecl))
1869 DECL_INLINE (newdecl) = 1;
1870 DECL_ABSTRACT_ORIGIN (newdecl)
1871 = DECL_ABSTRACT_ORIGIN (olddecl);
1876 /* If a previous declaration said inline, mark the
1877 definition as inlinable. */
1878 if (DECL_DECLARED_INLINE_P (newdecl)
1879 && !DECL_UNINLINABLE (newdecl))
1880 DECL_INLINE (newdecl) = 1;
1884 extern_changed = DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl);
1886 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1887 But preserve OLDDECL's DECL_UID and DECL_CONTEXT. */
1889 unsigned olddecl_uid = DECL_UID (olddecl);
1890 tree olddecl_context = DECL_CONTEXT (olddecl);
1892 memcpy ((char *) olddecl + sizeof (struct tree_common),
1893 (char *) newdecl + sizeof (struct tree_common),
1894 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
1895 switch (TREE_CODE (olddecl))
1905 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1906 (char *) newdecl + sizeof (struct tree_decl_common),
1907 tree_code_size (TREE_CODE (olddecl)) - sizeof (struct tree_decl_common));
1912 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1913 (char *) newdecl + sizeof (struct tree_decl_common),
1914 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common));
1916 DECL_UID (olddecl) = olddecl_uid;
1917 DECL_CONTEXT (olddecl) = olddecl_context;
1920 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1921 so that encode_section_info has a chance to look at the new decl
1922 flags and attributes. */
1923 if (DECL_RTL_SET_P (olddecl)
1924 && (TREE_CODE (olddecl) == FUNCTION_DECL
1925 || (TREE_CODE (olddecl) == VAR_DECL
1926 && TREE_STATIC (olddecl))))
1927 make_decl_rtl (olddecl);
1929 /* If we changed a function from DECL_EXTERNAL to !DECL_EXTERNAL,
1930 and the definition is coming from the old version, cgraph needs
1931 to be called again. */
1932 if (extern_changed && !new_is_definition
1933 && TREE_CODE (olddecl) == FUNCTION_DECL && DECL_INITIAL (olddecl))
1934 cgraph_finalize_function (olddecl, false);
1937 /* Handle when a new declaration NEWDECL has the same name as an old
1938 one OLDDECL in the same binding contour. Prints an error message
1941 If safely possible, alter OLDDECL to look like NEWDECL, and return
1942 true. Otherwise, return false. */
1945 duplicate_decls (tree newdecl, tree olddecl)
1947 tree newtype = NULL, oldtype = NULL;
1949 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1951 /* Avoid `unused variable' and other warnings warnings for OLDDECL. */
1952 TREE_NO_WARNING (olddecl) = 1;
1956 merge_decls (newdecl, olddecl, newtype, oldtype);
1961 /* Check whether decl-node NEW_DECL shadows an existing declaration. */
1963 warn_if_shadowing (tree new_decl)
1965 struct c_binding *b;
1967 /* Shadow warnings wanted? */
1969 /* No shadow warnings for internally generated vars. */
1970 || DECL_IS_BUILTIN (new_decl)
1971 /* No shadow warnings for vars made for inlining. */
1972 || DECL_FROM_INLINE (new_decl))
1975 /* Is anything being shadowed? Invisible decls do not count. */
1976 for (b = I_SYMBOL_BINDING (DECL_NAME (new_decl)); b; b = b->shadowed)
1977 if (b->decl && b->decl != new_decl && !b->invisible)
1979 tree old_decl = b->decl;
1981 if (old_decl == error_mark_node)
1983 warning (OPT_Wshadow, "declaration of %q+D shadows previous "
1984 "non-variable", new_decl);
1987 else if (TREE_CODE (old_decl) == PARM_DECL)
1988 warning (OPT_Wshadow, "declaration of %q+D shadows a parameter",
1990 else if (DECL_FILE_SCOPE_P (old_decl))
1991 warning (OPT_Wshadow, "declaration of %q+D shadows a global "
1992 "declaration", new_decl);
1993 else if (TREE_CODE (old_decl) == FUNCTION_DECL
1994 && DECL_BUILT_IN (old_decl))
1996 warning (OPT_Wshadow, "declaration of %q+D shadows "
1997 "a built-in function", new_decl);
2001 warning (OPT_Wshadow, "declaration of %q+D shadows a previous local",
2004 warning (OPT_Wshadow, "%Jshadowed declaration is here", old_decl);
2011 /* Subroutine of pushdecl.
2013 X is a TYPE_DECL for a typedef statement. Create a brand new
2014 ..._TYPE node (which will be just a variant of the existing
2015 ..._TYPE node with identical properties) and then install X
2016 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2018 The whole point here is to end up with a situation where each
2019 and every ..._TYPE node the compiler creates will be uniquely
2020 associated with AT MOST one node representing a typedef name.
2021 This way, even though the compiler substitutes corresponding
2022 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2023 early on, later parts of the compiler can always do the reverse
2024 translation and get back the corresponding typedef name. For
2027 typedef struct S MY_TYPE;
2030 Later parts of the compiler might only know that `object' was of
2031 type `struct S' if it were not for code just below. With this
2032 code however, later parts of the compiler see something like:
2034 struct S' == struct S
2035 typedef struct S' MY_TYPE;
2038 And they can then deduce (from the node for type struct S') that
2039 the original object declaration was:
2043 Being able to do this is important for proper support of protoize,
2044 and also for generating precise symbolic debugging information
2045 which takes full account of the programmer's (typedef) vocabulary.
2047 Obviously, we don't want to generate a duplicate ..._TYPE node if
2048 the TYPE_DECL node that we are now processing really represents a
2049 standard built-in type.
2051 Since all standard types are effectively declared at line zero
2052 in the source file, we can easily check to see if we are working
2053 on a standard type by checking the current value of lineno. */
2056 clone_underlying_type (tree x)
2058 if (DECL_IS_BUILTIN (x))
2060 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2061 TYPE_NAME (TREE_TYPE (x)) = x;
2063 else if (TREE_TYPE (x) != error_mark_node
2064 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2066 tree tt = TREE_TYPE (x);
2067 DECL_ORIGINAL_TYPE (x) = tt;
2068 tt = build_variant_type_copy (tt);
2070 TREE_USED (tt) = TREE_USED (x);
2075 /* Record a decl-node X as belonging to the current lexical scope.
2076 Check for errors (such as an incompatible declaration for the same
2077 name already seen in the same scope).
2079 Returns either X or an old decl for the same name.
2080 If an old decl is returned, it may have been smashed
2081 to agree with what X says. */
2086 tree name = DECL_NAME (x);
2087 struct c_scope *scope = current_scope;
2088 struct c_binding *b;
2089 bool nested = false;
2091 /* Functions need the lang_decl data. */
2092 if (TREE_CODE (x) == FUNCTION_DECL && !DECL_LANG_SPECIFIC (x))
2093 DECL_LANG_SPECIFIC (x) = GGC_CNEW (struct lang_decl);
2095 /* Must set DECL_CONTEXT for everything not at file scope or
2096 DECL_FILE_SCOPE_P won't work. Local externs don't count
2097 unless they have initializers (which generate code). */
2098 if (current_function_decl
2099 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
2100 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
2101 DECL_CONTEXT (x) = current_function_decl;
2103 /* If this is of variably modified type, prevent jumping into its
2105 if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == TYPE_DECL)
2106 && variably_modified_type_p (TREE_TYPE (x), NULL_TREE))
2107 c_begin_vm_scope (scope->depth);
2109 /* Anonymous decls are just inserted in the scope. */
2112 bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
2116 /* First, see if there is another declaration with the same name in
2117 the current scope. If there is, duplicate_decls may do all the
2118 work for us. If duplicate_decls returns false, that indicates
2119 two incompatible decls in the same scope; we are to silently
2120 replace the old one (duplicate_decls has issued all appropriate
2121 diagnostics). In particular, we should not consider possible
2122 duplicates in the external scope, or shadowing. */
2123 b = I_SYMBOL_BINDING (name);
2124 if (b && B_IN_SCOPE (b, scope))
2126 struct c_binding *b_ext, *b_use;
2127 tree type = TREE_TYPE (x);
2128 tree visdecl = b->decl;
2129 tree vistype = TREE_TYPE (visdecl);
2130 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
2131 && COMPLETE_TYPE_P (TREE_TYPE (x)))
2132 b->inner_comp = false;
2135 /* If this is an external linkage declaration, we should check
2136 for compatibility with the type in the external scope before
2137 setting the type at this scope based on the visible
2138 information only. */
2139 if (TREE_PUBLIC (x) && TREE_PUBLIC (visdecl))
2141 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
2142 b_ext = b_ext->shadowed;
2147 TREE_TYPE (b_use->decl) = b_use->type;
2150 if (duplicate_decls (x, b_use->decl))
2154 /* Save the updated type in the external scope and
2155 restore the proper type for this scope. */
2157 if (comptypes (vistype, type))
2158 thistype = composite_type (vistype, type);
2160 thistype = TREE_TYPE (b_use->decl);
2161 b_use->type = TREE_TYPE (b_use->decl);
2162 if (TREE_CODE (b_use->decl) == FUNCTION_DECL
2163 && DECL_BUILT_IN (b_use->decl))
2165 = build_type_attribute_variant (thistype,
2168 TREE_TYPE (b_use->decl) = thistype;
2173 goto skip_external_and_shadow_checks;
2176 /* All declarations with external linkage, and all external
2177 references, go in the external scope, no matter what scope is
2178 current. However, the binding in that scope is ignored for
2179 purposes of normal name lookup. A separate binding structure is
2180 created in the requested scope; this governs the normal
2181 visibility of the symbol.
2183 The binding in the externals scope is used exclusively for
2184 detecting duplicate declarations of the same object, no matter
2185 what scope they are in; this is what we do here. (C99 6.2.7p2:
2186 All declarations that refer to the same object or function shall
2187 have compatible type; otherwise, the behavior is undefined.) */
2188 if (DECL_EXTERNAL (x) || scope == file_scope)
2190 tree type = TREE_TYPE (x);
2193 bool type_saved = false;
2194 if (b && !B_IN_EXTERNAL_SCOPE (b)
2195 && (TREE_CODE (b->decl) == FUNCTION_DECL
2196 || TREE_CODE (b->decl) == VAR_DECL)
2197 && DECL_FILE_SCOPE_P (b->decl))
2200 vistype = TREE_TYPE (visdecl);
2202 if (scope != file_scope
2203 && !DECL_IN_SYSTEM_HEADER (x))
2204 warning (OPT_Wnested_externs, "nested extern declaration of %qD", x);
2206 while (b && !B_IN_EXTERNAL_SCOPE (b))
2208 /* If this decl might be modified, save its type. This is
2209 done here rather than when the decl is first bound
2210 because the type may change after first binding, through
2211 being completed or through attributes being added. If we
2212 encounter multiple such decls, only the first should have
2213 its type saved; the others will already have had their
2214 proper types saved and the types will not have changed as
2215 their scopes will not have been re-entered. */
2216 if (DECL_P (b->decl) && DECL_FILE_SCOPE_P (b->decl) && !type_saved)
2218 b->type = TREE_TYPE (b->decl);
2221 if (B_IN_FILE_SCOPE (b)
2222 && TREE_CODE (b->decl) == VAR_DECL
2223 && TREE_STATIC (b->decl)
2224 && TREE_CODE (TREE_TYPE (b->decl)) == ARRAY_TYPE
2225 && !TYPE_DOMAIN (TREE_TYPE (b->decl))
2226 && TREE_CODE (type) == ARRAY_TYPE
2227 && TYPE_DOMAIN (type)
2228 && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
2229 && !integer_zerop (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
2231 /* Array type completed in inner scope, which should be
2232 diagnosed if the completion does not have size 1 and
2233 it does not get completed in the file scope. */
2234 b->inner_comp = true;
2239 /* If a matching external declaration has been found, set its
2240 type to the composite of all the types of that declaration.
2241 After the consistency checks, it will be reset to the
2242 composite of the visible types only. */
2243 if (b && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2245 TREE_TYPE (b->decl) = b->type;
2247 /* The point of the same_translation_unit_p check here is,
2248 we want to detect a duplicate decl for a construct like
2249 foo() { extern bar(); } ... static bar(); but not if
2250 they are in different translation units. In any case,
2251 the static does not go in the externals scope. */
2253 && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2254 && duplicate_decls (x, b->decl))
2259 if (comptypes (vistype, type))
2260 thistype = composite_type (vistype, type);
2262 thistype = TREE_TYPE (b->decl);
2266 b->type = TREE_TYPE (b->decl);
2267 if (TREE_CODE (b->decl) == FUNCTION_DECL && DECL_BUILT_IN (b->decl))
2269 = build_type_attribute_variant (thistype,
2270 TYPE_ATTRIBUTES (b->type));
2271 TREE_TYPE (b->decl) = thistype;
2272 bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
2275 else if (TREE_PUBLIC (x))
2277 if (visdecl && !b && duplicate_decls (x, visdecl))
2279 /* An external declaration at block scope referring to a
2280 visible entity with internal linkage. The composite
2281 type will already be correct for this scope, so we
2282 just need to fall through to make the declaration in
2289 bind (name, x, external_scope, /*invisible=*/true,
2296 if (TREE_CODE (x) != PARM_DECL)
2297 warn_if_shadowing (x);
2299 skip_external_and_shadow_checks:
2300 if (TREE_CODE (x) == TYPE_DECL)
2301 clone_underlying_type (x);
2303 bind (name, x, scope, /*invisible=*/false, nested);
2305 /* If x's type is incomplete because it's based on a
2306 structure or union which has not yet been fully declared,
2307 attach it to that structure or union type, so we can go
2308 back and complete the variable declaration later, if the
2309 structure or union gets fully declared.
2311 If the input is erroneous, we can have error_mark in the type
2312 slot (e.g. "f(void a, ...)") - that doesn't count as an
2314 if (TREE_TYPE (x) != error_mark_node
2315 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2317 tree element = TREE_TYPE (x);
2319 while (TREE_CODE (element) == ARRAY_TYPE)
2320 element = TREE_TYPE (element);
2321 element = TYPE_MAIN_VARIANT (element);
2323 if ((TREE_CODE (element) == RECORD_TYPE
2324 || TREE_CODE (element) == UNION_TYPE)
2325 && (TREE_CODE (x) != TYPE_DECL
2326 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
2327 && !COMPLETE_TYPE_P (element))
2328 C_TYPE_INCOMPLETE_VARS (element)
2329 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
2334 /* Record X as belonging to file scope.
2335 This is used only internally by the Objective-C front end,
2336 and is limited to its needs. duplicate_decls is not called;
2337 if there is any preexisting decl for this identifier, it is an ICE. */
2340 pushdecl_top_level (tree x)
2343 bool nested = false;
2344 gcc_assert (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL);
2346 name = DECL_NAME (x);
2348 gcc_assert (TREE_CODE (x) == CONST_DECL || !I_SYMBOL_BINDING (name));
2350 if (TREE_PUBLIC (x))
2352 bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
2356 bind (name, x, file_scope, /*invisible=*/false, nested);
2362 implicit_decl_warning (tree id, tree olddecl)
2364 if (warn_implicit_function_declaration)
2367 pedwarn (G_("implicit declaration of function %qE"), id);
2369 warning (OPT_Wimplicit_function_declaration,
2370 G_("implicit declaration of function %qE"), id);
2372 locate_old_decl (olddecl, inform);
2376 /* Generate an implicit declaration for identifier FUNCTIONID as a
2377 function of type int (). */
2380 implicitly_declare (tree functionid)
2382 struct c_binding *b;
2386 for (b = I_SYMBOL_BINDING (functionid); b; b = b->shadowed)
2388 if (B_IN_SCOPE (b, external_scope))
2397 if (decl == error_mark_node)
2400 /* FIXME: Objective-C has weird not-really-builtin functions
2401 which are supposed to be visible automatically. They wind up
2402 in the external scope because they're pushed before the file
2403 scope gets created. Catch this here and rebind them into the
2405 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
2407 bind (functionid, decl, file_scope,
2408 /*invisible=*/false, /*nested=*/true);
2413 tree newtype = default_function_type;
2415 TREE_TYPE (decl) = b->type;
2416 /* Implicit declaration of a function already declared
2417 (somehow) in a different scope, or as a built-in.
2418 If this is the first time this has happened, warn;
2419 then recycle the old declaration but with the new type. */
2420 if (!C_DECL_IMPLICIT (decl))
2422 implicit_decl_warning (functionid, decl);
2423 C_DECL_IMPLICIT (decl) = 1;
2425 if (DECL_BUILT_IN (decl))
2427 newtype = build_type_attribute_variant (newtype,
2429 (TREE_TYPE (decl)));
2430 if (!comptypes (newtype, TREE_TYPE (decl)))
2432 warning (0, "incompatible implicit declaration of built-in"
2433 " function %qD", decl);
2434 newtype = TREE_TYPE (decl);
2439 if (!comptypes (newtype, TREE_TYPE (decl)))
2441 error ("incompatible implicit declaration of function %qD",
2443 locate_old_decl (decl, error);
2446 b->type = TREE_TYPE (decl);
2447 TREE_TYPE (decl) = newtype;
2448 bind (functionid, decl, current_scope,
2449 /*invisible=*/false, /*nested=*/true);
2454 /* Not seen before. */
2455 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2456 DECL_EXTERNAL (decl) = 1;
2457 TREE_PUBLIC (decl) = 1;
2458 C_DECL_IMPLICIT (decl) = 1;
2459 implicit_decl_warning (functionid, 0);
2460 asmspec_tree = maybe_apply_renaming_pragma (decl, /*asmname=*/NULL);
2462 set_user_assembler_name (decl, TREE_STRING_POINTER (asmspec_tree));
2464 /* C89 says implicit declarations are in the innermost block.
2465 So we record the decl in the standard fashion. */
2466 decl = pushdecl (decl);
2468 /* No need to call objc_check_decl here - it's a function type. */
2469 rest_of_decl_compilation (decl, 0, 0);
2471 /* Write a record describing this implicit function declaration
2472 to the prototypes file (if requested). */
2473 gen_aux_info_record (decl, 0, 1, 0);
2475 /* Possibly apply some default attributes to this implicit declaration. */
2476 decl_attributes (&decl, NULL_TREE, 0);
2481 /* Issue an error message for a reference to an undeclared variable
2482 ID, including a reference to a builtin outside of function-call
2483 context. Establish a binding of the identifier to error_mark_node
2484 in an appropriate scope, which will suppress further errors for the
2485 same identifier. The error message should be given location LOC. */
2487 undeclared_variable (tree id, location_t loc)
2489 static bool already = false;
2490 struct c_scope *scope;
2492 if (current_function_decl == 0)
2494 error ("%H%qE undeclared here (not in a function)", &loc, id);
2495 scope = current_scope;
2499 error ("%H%qE undeclared (first use in this function)", &loc, id);
2503 error ("%H(Each undeclared identifier is reported only once", &loc);
2504 error ("%Hfor each function it appears in.)", &loc);
2508 /* If we are parsing old-style parameter decls, current_function_decl
2509 will be nonnull but current_function_scope will be null. */
2510 scope = current_function_scope ? current_function_scope : current_scope;
2512 bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
2515 /* Subroutine of lookup_label, declare_label, define_label: construct a
2516 LABEL_DECL with all the proper frills. */
2519 make_label (tree name, location_t location)
2521 tree label = build_decl (LABEL_DECL, name, void_type_node);
2523 DECL_CONTEXT (label) = current_function_decl;
2524 DECL_MODE (label) = VOIDmode;
2525 DECL_SOURCE_LOCATION (label) = location;
2530 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2531 Create one if none exists so far for the current function.
2532 This is called when a label is used in a goto expression or
2533 has its address taken. */
2536 lookup_label (tree name)
2540 if (current_function_decl == 0)
2542 error ("label %qE referenced outside of any function", name);
2546 /* Use a label already defined or ref'd with this name, but not if
2547 it is inherited from a containing function and wasn't declared
2549 label = I_LABEL_DECL (name);
2550 if (label && (DECL_CONTEXT (label) == current_function_decl
2551 || C_DECLARED_LABEL_FLAG (label)))
2553 /* If the label has only been declared, update its apparent
2554 location to point here, for better diagnostics if it
2555 turns out not to have been defined. */
2556 if (!TREE_USED (label))
2557 DECL_SOURCE_LOCATION (label) = input_location;
2561 /* No label binding for that identifier; make one. */
2562 label = make_label (name, input_location);
2564 /* Ordinary labels go in the current function scope. */
2565 bind (name, label, current_function_scope,
2566 /*invisible=*/false, /*nested=*/false);
2570 /* Make a label named NAME in the current function, shadowing silently
2571 any that may be inherited from containing functions or containing
2572 scopes. This is called for __label__ declarations. */
2575 declare_label (tree name)
2577 struct c_binding *b = I_LABEL_BINDING (name);
2580 /* Check to make sure that the label hasn't already been declared
2582 if (b && B_IN_CURRENT_SCOPE (b))
2584 error ("duplicate label declaration %qE", name);
2585 locate_old_decl (b->decl, error);
2587 /* Just use the previous declaration. */
2591 label = make_label (name, input_location);
2592 C_DECLARED_LABEL_FLAG (label) = 1;
2594 /* Declared labels go in the current scope. */
2595 bind (name, label, current_scope,
2596 /*invisible=*/false, /*nested=*/false);
2600 /* Define a label, specifying the location in the source file.
2601 Return the LABEL_DECL node for the label, if the definition is valid.
2602 Otherwise return 0. */
2605 define_label (location_t location, tree name)
2607 /* Find any preexisting label with this name. It is an error
2608 if that label has already been defined in this function, or
2609 if there is a containing function with a declared label with
2611 tree label = I_LABEL_DECL (name);
2612 struct c_label_list *nlist_se, *nlist_vm;
2615 && ((DECL_CONTEXT (label) == current_function_decl
2616 && DECL_INITIAL (label) != 0)
2617 || (DECL_CONTEXT (label) != current_function_decl
2618 && C_DECLARED_LABEL_FLAG (label))))
2620 error ("%Hduplicate label %qD", &location, label);
2621 locate_old_decl (label, error);
2624 else if (label && DECL_CONTEXT (label) == current_function_decl)
2626 /* The label has been used or declared already in this function,
2627 but not defined. Update its location to point to this
2629 if (C_DECL_UNDEFINABLE_STMT_EXPR (label))
2630 error ("%Jjump into statement expression", label);
2631 if (C_DECL_UNDEFINABLE_VM (label))
2632 error ("%Jjump into scope of identifier with variably modified type",
2634 DECL_SOURCE_LOCATION (label) = location;
2638 /* No label binding for that identifier; make one. */
2639 label = make_label (name, location);
2641 /* Ordinary labels go in the current function scope. */
2642 bind (name, label, current_function_scope,
2643 /*invisible=*/false, /*nested=*/false);
2646 if (!in_system_header && lookup_name (name))
2647 warning (OPT_Wtraditional, "%Htraditional C lacks a separate namespace "
2648 "for labels, identifier %qE conflicts", &location, name);
2650 nlist_se = XOBNEW (&parser_obstack, struct c_label_list);
2651 nlist_se->next = label_context_stack_se->labels_def;
2652 nlist_se->label = label;
2653 label_context_stack_se->labels_def = nlist_se;
2655 nlist_vm = XOBNEW (&parser_obstack, struct c_label_list);
2656 nlist_vm->next = label_context_stack_vm->labels_def;
2657 nlist_vm->label = label;
2658 label_context_stack_vm->labels_def = nlist_vm;
2660 /* Mark label as having been defined. */
2661 DECL_INITIAL (label) = error_mark_node;
2665 /* Given NAME, an IDENTIFIER_NODE,
2666 return the structure (or union or enum) definition for that name.
2667 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2668 CODE says which kind of type the caller wants;
2669 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2670 If the wrong kind of type is found, an error is reported. */
2673 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2675 struct c_binding *b = I_TAG_BINDING (name);
2681 /* We only care about whether it's in this level if
2682 thislevel_only was set or it might be a type clash. */
2683 if (thislevel_only || TREE_CODE (b->decl) != code)
2685 /* For our purposes, a tag in the external scope is the same as
2686 a tag in the file scope. (Primarily relevant to Objective-C
2687 and its builtin structure tags, which get pushed before the
2688 file scope is created.) */
2689 if (B_IN_CURRENT_SCOPE (b)
2690 || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
2694 if (thislevel_only && !thislevel)
2697 if (TREE_CODE (b->decl) != code)
2699 /* Definition isn't the kind we were looking for. */
2700 pending_invalid_xref = name;
2701 pending_invalid_xref_location = input_location;
2703 /* If in the same binding level as a declaration as a tag
2704 of a different type, this must not be allowed to
2705 shadow that tag, so give the error immediately.
2706 (For example, "struct foo; union foo;" is invalid.) */
2708 pending_xref_error ();
2713 /* Print an error message now
2714 for a recent invalid struct, union or enum cross reference.
2715 We don't print them immediately because they are not invalid
2716 when used in the `struct foo;' construct for shadowing. */
2719 pending_xref_error (void)
2721 if (pending_invalid_xref != 0)
2722 error ("%H%qE defined as wrong kind of tag",
2723 &pending_invalid_xref_location, pending_invalid_xref);
2724 pending_invalid_xref = 0;
2728 /* Look up NAME in the current scope and its superiors
2729 in the namespace of variables, functions and typedefs.
2730 Return a ..._DECL node of some kind representing its definition,
2731 or return 0 if it is undefined. */
2734 lookup_name (tree name)
2736 struct c_binding *b = I_SYMBOL_BINDING (name);
2737 if (b && !b->invisible)
2742 /* Similar to `lookup_name' but look only at the indicated scope. */
2745 lookup_name_in_scope (tree name, struct c_scope *scope)
2747 struct c_binding *b;
2749 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2750 if (B_IN_SCOPE (b, scope))
2755 /* Create the predefined scalar types of C,
2756 and some nodes representing standard constants (0, 1, (void *) 0).
2757 Initialize the global scope.
2758 Make definitions for built-in primitive functions. */
2761 c_init_decl_processing (void)
2763 location_t save_loc = input_location;
2765 /* Initialize reserved words for parser. */
2768 current_function_decl = 0;
2770 gcc_obstack_init (&parser_obstack);
2772 /* Make the externals scope. */
2774 external_scope = current_scope;
2776 /* Declarations from c_common_nodes_and_builtins must not be associated
2777 with this input file, lest we get differences between using and not
2778 using preprocessed headers. */
2779 #ifdef USE_MAPPED_LOCATION
2780 input_location = BUILTINS_LOCATION;
2782 input_location.file = "<built-in>";
2783 input_location.line = 0;
2786 build_common_tree_nodes (flag_signed_char, false);
2788 c_common_nodes_and_builtins ();
2790 /* In C, comparisons and TRUTH_* expressions have type int. */
2791 truthvalue_type_node = integer_type_node;
2792 truthvalue_true_node = integer_one_node;
2793 truthvalue_false_node = integer_zero_node;
2795 /* Even in C99, which has a real boolean type. */
2796 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2797 boolean_type_node));
2799 input_location = save_loc;
2801 pedantic_lvalues = true;
2803 make_fname_decl = c_make_fname_decl;
2804 start_fname_decls ();
2807 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2808 decl, NAME is the initialization string and TYPE_DEP indicates whether
2809 NAME depended on the type of the function. As we don't yet implement
2810 delayed emission of static data, we mark the decl as emitted
2811 so it is not placed in the output. Anything using it must therefore pull
2812 out the STRING_CST initializer directly. FIXME. */
2815 c_make_fname_decl (tree id, int type_dep)
2817 const char *name = fname_as_string (type_dep);
2818 tree decl, type, init;
2819 size_t length = strlen (name);
2821 type = build_array_type (char_type_node,
2822 build_index_type (size_int (length)));
2823 type = c_build_qualified_type (type, TYPE_QUAL_CONST);
2825 decl = build_decl (VAR_DECL, id, type);
2827 TREE_STATIC (decl) = 1;
2828 TREE_READONLY (decl) = 1;
2829 DECL_ARTIFICIAL (decl) = 1;
2831 init = build_string (length + 1, name);
2832 free ((char *) name);
2833 TREE_TYPE (init) = type;
2834 DECL_INITIAL (decl) = init;
2836 TREE_USED (decl) = 1;
2838 if (current_function_decl
2839 /* For invalid programs like this:
2842 const char* p = __FUNCTION__;
2844 the __FUNCTION__ is believed to appear in K&R style function
2845 parameter declarator. In that case we still don't have
2847 && (!errorcount || current_function_scope))
2849 DECL_CONTEXT (decl) = current_function_decl;
2850 bind (id, decl, current_function_scope,
2851 /*invisible=*/false, /*nested=*/false);
2854 finish_decl (decl, init, NULL_TREE);
2860 c_builtin_function (tree decl)
2862 tree type = TREE_TYPE (decl);
2863 tree id = DECL_NAME (decl);
2865 const char *name = IDENTIFIER_POINTER (id);
2866 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
2867 C_DECL_BUILTIN_PROTOTYPE (decl) = (TYPE_ARG_TYPES (type) != 0);
2869 /* Should never be called on a symbol with a preexisting meaning. */
2870 gcc_assert (!I_SYMBOL_BINDING (id));
2872 bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
2874 /* Builtins in the implementation namespace are made visible without
2875 needing to be explicitly declared. See push_file_scope. */
2876 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2878 TREE_CHAIN (decl) = visible_builtins;
2879 visible_builtins = decl;
2885 /* Called when a declaration is seen that contains no names to declare.
2886 If its type is a reference to a structure, union or enum inherited
2887 from a containing scope, shadow that tag name for the current scope
2888 with a forward reference.
2889 If its type defines a new named structure or union
2890 or defines an enum, it is valid but we need not do anything here.
2891 Otherwise, it is an error. */
2894 shadow_tag (const struct c_declspecs *declspecs)
2896 shadow_tag_warned (declspecs, 0);
2899 /* WARNED is 1 if we have done a pedwarn, 2 if we have done a warning,
2902 shadow_tag_warned (const struct c_declspecs *declspecs, int warned)
2904 bool found_tag = false;
2906 if (declspecs->type && !declspecs->default_int_p && !declspecs->typedef_p)
2908 tree value = declspecs->type;
2909 enum tree_code code = TREE_CODE (value);
2911 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2912 /* Used to test also that TYPE_SIZE (value) != 0.
2913 That caused warning for `struct foo;' at top level in the file. */
2915 tree name = TYPE_NAME (value);
2922 if (warned != 1 && code != ENUMERAL_TYPE)
2923 /* Empty unnamed enum OK */
2925 pedwarn ("unnamed struct/union that defines no instances");
2929 else if (!declspecs->tag_defined_p
2930 && declspecs->storage_class != csc_none)
2933 pedwarn ("empty declaration with storage class specifier "
2934 "does not redeclare tag");
2936 pending_xref_error ();
2938 else if (!declspecs->tag_defined_p
2939 && (declspecs->const_p
2940 || declspecs->volatile_p
2941 || declspecs->restrict_p))
2944 pedwarn ("empty declaration with type qualifier "
2945 "does not redeclare tag");
2947 pending_xref_error ();
2951 pending_invalid_xref = 0;
2952 t = lookup_tag (code, name, 1);
2956 t = make_node (code);
2963 if (warned != 1 && !in_system_header)
2965 pedwarn ("useless type name in empty declaration");
2970 else if (warned != 1 && !in_system_header && declspecs->typedef_p)
2972 pedwarn ("useless type name in empty declaration");
2976 pending_invalid_xref = 0;
2978 if (declspecs->inline_p)
2980 error ("%<inline%> in empty declaration");
2984 if (current_scope == file_scope && declspecs->storage_class == csc_auto)
2986 error ("%<auto%> in file-scope empty declaration");
2990 if (current_scope == file_scope && declspecs->storage_class == csc_register)
2992 error ("%<register%> in file-scope empty declaration");
2996 if (!warned && !in_system_header && declspecs->storage_class != csc_none)
2998 warning (0, "useless storage class specifier in empty declaration");
3002 if (!warned && !in_system_header && declspecs->thread_p)
3004 warning (0, "useless %<__thread%> in empty declaration");
3008 if (!warned && !in_system_header && (declspecs->const_p
3009 || declspecs->volatile_p
3010 || declspecs->restrict_p))
3012 warning (0, "useless type qualifier in empty declaration");
3019 pedwarn ("empty declaration");
3024 /* Return the qualifiers from SPECS as a bitwise OR of TYPE_QUAL_*
3025 bits. SPECS represents declaration specifiers that the grammar
3026 only permits to contain type qualifiers and attributes. */
3029 quals_from_declspecs (const struct c_declspecs *specs)
3031 int quals = ((specs->const_p ? TYPE_QUAL_CONST : 0)
3032 | (specs->volatile_p ? TYPE_QUAL_VOLATILE : 0)
3033 | (specs->restrict_p ? TYPE_QUAL_RESTRICT : 0));
3034 gcc_assert (!specs->type
3035 && !specs->decl_attr
3036 && specs->typespec_word == cts_none
3037 && specs->storage_class == csc_none
3038 && !specs->typedef_p
3039 && !specs->explicit_signed_p
3040 && !specs->deprecated_p
3042 && !specs->long_long_p
3045 && !specs->unsigned_p
3046 && !specs->complex_p
3048 && !specs->thread_p);
3052 /* Construct an array declarator. EXPR is the expression inside [],
3053 or NULL_TREE. QUALS are the type qualifiers inside the [] (to be
3054 applied to the pointer to which a parameter array is converted).
3055 STATIC_P is true if "static" is inside the [], false otherwise.
3056 VLA_UNSPEC_P is true if the array is [*], a VLA of unspecified
3057 length which is nevertheless a complete type, false otherwise. The
3058 field for the contained declarator is left to be filled in by
3059 set_array_declarator_inner. */
3061 struct c_declarator *
3062 build_array_declarator (tree expr, struct c_declspecs *quals, bool static_p,
3065 struct c_declarator *declarator = XOBNEW (&parser_obstack,
3066 struct c_declarator);
3067 declarator->kind = cdk_array;
3068 declarator->declarator = 0;
3069 declarator->u.array.dimen = expr;
3072 declarator->u.array.attrs = quals->attrs;
3073 declarator->u.array.quals = quals_from_declspecs (quals);
3077 declarator->u.array.attrs = NULL_TREE;
3078 declarator->u.array.quals = 0;
3080 declarator->u.array.static_p = static_p;
3081 declarator->u.array.vla_unspec_p = vla_unspec_p;
3082 if (pedantic && !flag_isoc99)
3084 if (static_p || quals != NULL)
3085 pedwarn ("ISO C90 does not support %<static%> or type "
3086 "qualifiers in parameter array declarators");
3088 pedwarn ("ISO C90 does not support %<[*]%> array declarators");
3092 if (!current_scope->parm_flag)
3095 error ("%<[*]%> not allowed in other than function prototype scope");
3096 declarator->u.array.vla_unspec_p = false;
3099 current_scope->had_vla_unspec = true;
3104 /* Set the contained declarator of an array declarator. DECL is the
3105 declarator, as constructed by build_array_declarator; INNER is what
3106 appears on the left of the []. ABSTRACT_P is true if it is an
3107 abstract declarator, false otherwise; this is used to reject static
3108 and type qualifiers in abstract declarators, where they are not in
3109 the C99 grammar (subject to possible change in DR#289). */
3111 struct c_declarator *
3112 set_array_declarator_inner (struct c_declarator *decl,
3113 struct c_declarator *inner, bool abstract_p)
3115 decl->declarator = inner;
3116 if (abstract_p && (decl->u.array.quals != TYPE_UNQUALIFIED
3117 || decl->u.array.attrs != NULL_TREE
3118 || decl->u.array.static_p))
3119 error ("static or type qualifiers in abstract declarator");
3123 /* INIT is a constructor that forms DECL's initializer. If the final
3124 element initializes a flexible array field, add the size of that
3125 initializer to DECL's size. */
3128 add_flexible_array_elts_to_size (tree decl, tree init)
3132 if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init)))
3135 elt = VEC_last (constructor_elt, CONSTRUCTOR_ELTS (init))->value;
3136 type = TREE_TYPE (elt);
3137 if (TREE_CODE (type) == ARRAY_TYPE
3138 && TYPE_SIZE (type) == NULL_TREE
3139 && TYPE_DOMAIN (type) != NULL_TREE
3140 && TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL_TREE)
3142 complete_array_type (&type, elt, false);
3144 = size_binop (PLUS_EXPR, DECL_SIZE (decl), TYPE_SIZE (type));
3145 DECL_SIZE_UNIT (decl)
3146 = size_binop (PLUS_EXPR, DECL_SIZE_UNIT (decl), TYPE_SIZE_UNIT (type));
3150 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3153 groktypename (struct c_type_name *type_name)
3156 tree attrs = type_name->specs->attrs;
3158 type_name->specs->attrs = NULL_TREE;
3160 type = grokdeclarator (type_name->declarator, type_name->specs, TYPENAME,
3163 /* Apply attributes. */
3164 decl_attributes (&type, attrs, 0);
3169 /* Decode a declarator in an ordinary declaration or data definition.
3170 This is called as soon as the type information and variable name
3171 have been parsed, before parsing the initializer if any.
3172 Here we create the ..._DECL node, fill in its type,
3173 and put it on the list of decls for the current context.
3174 The ..._DECL node is returned as the value.
3176 Exception: for arrays where the length is not specified,
3177 the type is left null, to be filled in by `finish_decl'.
3179 Function definitions do not come here; they go to start_function
3180 instead. However, external and forward declarations of functions
3181 do go through here. Structure field declarations are done by
3182 grokfield and not through here. */
3185 start_decl (struct c_declarator *declarator, struct c_declspecs *declspecs,
3186 bool initialized, tree attributes)
3191 /* An object declared as __attribute__((deprecated)) suppresses
3192 warnings of uses of other deprecated items. */
3193 if (lookup_attribute ("deprecated", attributes))
3194 deprecated_state = DEPRECATED_SUPPRESS;
3196 decl = grokdeclarator (declarator, declspecs,
3197 NORMAL, initialized, NULL);
3201 deprecated_state = DEPRECATED_NORMAL;
3203 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3204 && MAIN_NAME_P (DECL_NAME (decl)))
3205 warning (OPT_Wmain, "%q+D is usually a function", decl);
3208 /* Is it valid for this decl to have an initializer at all?
3209 If not, set INITIALIZED to zero, which will indirectly
3210 tell 'finish_decl' to ignore the initializer once it is parsed. */
3211 switch (TREE_CODE (decl))
3214 error ("typedef %qD is initialized (use __typeof__ instead)", decl);
3219 error ("function %qD is initialized like a variable", decl);
3224 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3225 error ("parameter %qD is initialized", decl);
3230 /* Don't allow initializations for incomplete types except for
3231 arrays which might be completed by the initialization. */
3233 /* This can happen if the array size is an undefined macro.
3234 We already gave a warning, so we don't need another one. */
3235 if (TREE_TYPE (decl) == error_mark_node)
3237 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3239 /* A complete type is ok if size is fixed. */
3241 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3242 || C_DECL_VARIABLE_SIZE (decl))
3244 error ("variable-sized object may not be initialized");
3248 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3250 error ("variable %qD has initializer but incomplete type", decl);
3253 else if (C_DECL_VARIABLE_SIZE (decl))
3255 /* Although C99 is unclear about whether incomplete arrays
3256 of VLAs themselves count as VLAs, it does not make
3257 sense to permit them to be initialized given that
3258 ordinary VLAs may not be initialized. */
3259 error ("variable-sized object may not be initialized");
3266 if (current_scope == file_scope)
3267 TREE_STATIC (decl) = 1;
3269 /* Tell 'pushdecl' this is an initialized decl
3270 even though we don't yet have the initializer expression.
3271 Also tell 'finish_decl' it may store the real initializer. */
3272 DECL_INITIAL (decl) = error_mark_node;
3275 /* If this is a function declaration, write a record describing it to the
3276 prototypes file (if requested). */
3278 if (TREE_CODE (decl) == FUNCTION_DECL)
3279 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3281 /* ANSI specifies that a tentative definition which is not merged with
3282 a non-tentative definition behaves exactly like a definition with an
3283 initializer equal to zero. (Section 3.7.2)
3285 -fno-common gives strict ANSI behavior, though this tends to break
3286 a large body of code that grew up without this rule.
3288 Thread-local variables are never common, since there's no entrenched
3289 body of code to break, and it allows more efficient variable references
3290 in the presence of dynamic linking. */
3292 if (TREE_CODE (decl) == VAR_DECL
3294 && TREE_PUBLIC (decl)
3295 && !DECL_THREAD_LOCAL_P (decl)
3297 DECL_COMMON (decl) = 1;
3299 /* Set attributes here so if duplicate decl, will have proper attributes. */
3300 decl_attributes (&decl, attributes, 0);
3302 /* Handle gnu_inline attribute. */
3303 if (declspecs->inline_p
3304 && !flag_gnu89_inline
3305 && TREE_CODE (decl) == FUNCTION_DECL
3306 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl)))
3308 if (declspecs->storage_class == csc_auto && current_scope != file_scope)
3310 else if (declspecs->storage_class != csc_static)
3311 DECL_EXTERNAL (decl) = !DECL_EXTERNAL (decl);
3314 if (TREE_CODE (decl) == FUNCTION_DECL
3315 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
3317 struct c_declarator *ce = declarator;
3319 if (ce->kind == cdk_pointer)
3320 ce = declarator->declarator;
3321 if (ce->kind == cdk_function)
3323 tree args = ce->u.arg_info->parms;
3324 for (; args; args = TREE_CHAIN (args))
3326 tree type = TREE_TYPE (args);
3327 if (type && INTEGRAL_TYPE_P (type)
3328 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
3329 DECL_ARG_TYPE (args) = integer_type_node;
3334 if (TREE_CODE (decl) == FUNCTION_DECL
3335 && DECL_DECLARED_INLINE_P (decl)
3336 && DECL_UNINLINABLE (decl)
3337 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3338 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
3341 /* C99 6.7.4p3: An inline definition of a function with external
3342 linkage shall not contain a definition of a modifiable object
3343 with static storage duration... */
3344 if (TREE_CODE (decl) == VAR_DECL
3345 && current_scope != file_scope
3346 && TREE_STATIC (decl)
3347 && DECL_DECLARED_INLINE_P (current_function_decl)
3348 && DECL_EXTERNAL (current_function_decl))
3349 pedwarn ("%q+D is static but declared in inline function %qD "
3350 "which is not static", decl, current_function_decl);
3352 /* Add this decl to the current scope.
3353 TEM may equal DECL or it may be a previous decl of the same name. */
3354 tem = pushdecl (decl);
3356 if (initialized && DECL_EXTERNAL (tem))
3358 DECL_EXTERNAL (tem) = 0;
3359 TREE_STATIC (tem) = 1;
3365 /* Initialize EH if not initialized yet and exceptions are enabled. */
3368 c_maybe_initialize_eh (void)
3370 if (!flag_exceptions || c_eh_initialized_p)
3373 c_eh_initialized_p = true;
3374 eh_personality_libfunc
3375 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3376 ? "__gcc_personality_sj0"
3377 : "__gcc_personality_v0");
3378 default_init_unwind_resume_libfunc ();
3379 using_eh_for_cleanups ();
3382 /* Finish processing of a declaration;
3383 install its initial value.
3384 If the length of an array type is not known before,
3385 it must be determined now, from the initial value, or it is an error. */
3388 finish_decl (tree decl, tree init, tree asmspec_tree)
3390 tree type = TREE_TYPE (decl);
3391 int was_incomplete = (DECL_SIZE (decl) == 0);
3392 const char *asmspec = 0;
3394 /* If a name was specified, get the string. */
3395 if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL)
3396 && DECL_FILE_SCOPE_P (decl))
3397 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3399 asmspec = TREE_STRING_POINTER (asmspec_tree);
3401 /* If `start_decl' didn't like having an initialization, ignore it now. */
3402 if (init != 0 && DECL_INITIAL (decl) == 0)
3405 /* Don't crash if parm is initialized. */
3406 if (TREE_CODE (decl) == PARM_DECL)
3410 store_init_value (decl, init);
3412 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
3413 || TREE_CODE (decl) == FUNCTION_DECL
3414 || TREE_CODE (decl) == FIELD_DECL))
3415 objc_check_decl (decl);
3417 /* Deduce size of array from initialization, if not already known. */
3418 if (TREE_CODE (type) == ARRAY_TYPE
3419 && TYPE_DOMAIN (type) == 0
3420 && TREE_CODE (decl) != TYPE_DECL)
3423 = (TREE_STATIC (decl)
3424 /* Even if pedantic, an external linkage array
3425 may have incomplete type at first. */
3426 ? pedantic && !TREE_PUBLIC (decl)
3427 : !DECL_EXTERNAL (decl));
3429 = complete_array_type (&TREE_TYPE (decl), DECL_INITIAL (decl),
3432 /* Get the completed type made by complete_array_type. */
3433 type = TREE_TYPE (decl);
3438 error ("initializer fails to determine size of %q+D", decl);
3443 error ("array size missing in %q+D", decl);
3444 /* If a `static' var's size isn't known,
3445 make it extern as well as static, so it does not get
3447 If it is not `static', then do not mark extern;
3448 finish_incomplete_decl will give it a default size
3449 and it will get allocated. */
3450 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
3451 DECL_EXTERNAL (decl) = 1;
3455 error ("zero or negative size array %q+D", decl);
3459 /* For global variables, update the copy of the type that
3460 exists in the binding. */
3461 if (TREE_PUBLIC (decl))
3463 struct c_binding *b_ext = I_SYMBOL_BINDING (DECL_NAME (decl));
3464 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
3465 b_ext = b_ext->shadowed;
3469 b_ext->type = composite_type (b_ext->type, type);
3480 if (DECL_INITIAL (decl))
3481 TREE_TYPE (DECL_INITIAL (decl)) = type;
3483 layout_decl (decl, 0);
3486 if (TREE_CODE (decl) == VAR_DECL)
3488 if (init && TREE_CODE (init) == CONSTRUCTOR)
3489 add_flexible_array_elts_to_size (decl, init);
3491 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3492 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3493 layout_decl (decl, 0);
3495 if (DECL_SIZE (decl) == 0
3496 /* Don't give an error if we already gave one earlier. */
3497 && TREE_TYPE (decl) != error_mark_node
3498 && (TREE_STATIC (decl)
3499 /* A static variable with an incomplete type
3500 is an error if it is initialized.
3501 Also if it is not file scope.
3502 Otherwise, let it through, but if it is not `extern'
3503 then it may cause an error message later. */
3504 ? (DECL_INITIAL (decl) != 0
3505 || !DECL_FILE_SCOPE_P (decl))
3506 /* An automatic variable with an incomplete type
3508 : !DECL_EXTERNAL (decl)))
3510 error ("storage size of %q+D isn%'t known", decl);
3511 TREE_TYPE (decl) = error_mark_node;
3514 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3515 && DECL_SIZE (decl) != 0)
3517 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3518 constant_expression_warning (DECL_SIZE (decl));
3520 error ("storage size of %q+D isn%'t constant", decl);
3523 if (TREE_USED (type))
3524 TREE_USED (decl) = 1;
3527 /* If this is a function and an assembler name is specified, reset DECL_RTL
3528 so we can give it its new name. Also, update built_in_decls if it
3529 was a normal built-in. */
3530 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3532 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
3533 set_builtin_user_assembler_name (decl, asmspec);
3534 set_user_assembler_name (decl, asmspec);
3537 /* If #pragma weak was used, mark the decl weak now. */
3538 maybe_apply_pragma_weak (decl);
3540 /* Output the assembler code and/or RTL code for variables and functions,
3541 unless the type is an undefined structure or union.
3542 If not, it will get done when the type is completed. */
3544 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3546 /* Determine the ELF visibility. */
3547 if (TREE_PUBLIC (decl))
3548 c_determine_visibility (decl);
3550 /* This is a no-op in c-lang.c or something real in objc-act.c. */
3551 if (c_dialect_objc ())
3552 objc_check_decl (decl);
3556 /* If this is not a static variable, issue a warning.
3557 It doesn't make any sense to give an ASMSPEC for an
3558 ordinary, non-register local variable. Historically,
3559 GCC has accepted -- but ignored -- the ASMSPEC in
3561 if (!DECL_FILE_SCOPE_P (decl)
3562 && TREE_CODE (decl) == VAR_DECL
3563 && !C_DECL_REGISTER (decl)
3564 && !TREE_STATIC (decl))
3565 warning (0, "ignoring asm-specifier for non-static local "
3566 "variable %q+D", decl);
3568 set_user_assembler_name (decl, asmspec);
3571 if (DECL_FILE_SCOPE_P (decl))
3573 if (DECL_INITIAL (decl) == NULL_TREE
3574 || DECL_INITIAL (decl) == error_mark_node)
3575 /* Don't output anything
3576 when a tentative file-scope definition is seen.
3577 But at end of compilation, do output code for them. */
3578 DECL_DEFER_OUTPUT (decl) = 1;
3579 rest_of_decl_compilation (decl, true, 0);
3583 /* In conjunction with an ASMSPEC, the `register'
3584 keyword indicates that we should place the variable
3585 in a particular register. */
3586 if (asmspec && C_DECL_REGISTER (decl))
3588 DECL_HARD_REGISTER (decl) = 1;
3589 /* This cannot be done for a structure with volatile
3590 fields, on which DECL_REGISTER will have been
3592 if (!DECL_REGISTER (decl))
3593 error ("cannot put object with volatile field into register");
3596 if (TREE_CODE (decl) != FUNCTION_DECL)
3598 /* If we're building a variable sized type, and we might be
3599 reachable other than via the top of the current binding
3600 level, then create a new BIND_EXPR so that we deallocate
3601 the object at the right time. */
3602 /* Note that DECL_SIZE can be null due to errors. */
3603 if (DECL_SIZE (decl)
3604 && !TREE_CONSTANT (DECL_SIZE (decl))
3605 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
3608 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
3609 TREE_SIDE_EFFECTS (bind) = 1;
3611 BIND_EXPR_BODY (bind) = push_stmt_list ();
3613 add_stmt (build_stmt (DECL_EXPR, decl));
3618 if (!DECL_FILE_SCOPE_P (decl))
3620 /* Recompute the RTL of a local array now
3621 if it used to be an incomplete type. */
3623 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
3625 /* If we used it already as memory, it must stay in memory. */
3626 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3627 /* If it's still incomplete now, no init will save it. */
3628 if (DECL_SIZE (decl) == 0)
3629 DECL_INITIAL (decl) = 0;
3634 /* If this was marked 'used', be sure it will be output. */
3635 if (!flag_unit_at_a_time && lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
3636 mark_decl_referenced (decl);
3638 if (TREE_CODE (decl) == TYPE_DECL)
3640 if (!DECL_FILE_SCOPE_P (decl)
3641 && variably_modified_type_p (TREE_TYPE (decl), NULL_TREE))
3642 add_stmt (build_stmt (DECL_EXPR, decl));
3644 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl), 0);
3647 /* At the end of a declaration, throw away any variable type sizes
3648 of types defined inside that declaration. There is no use
3649 computing them in the following function definition. */
3650 if (current_scope == file_scope)
3651 get_pending_sizes ();
3653 /* Install a cleanup (aka destructor) if one was given. */
3654 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
3656 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
3659 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
3660 tree cleanup_decl = lookup_name (cleanup_id);
3663 /* Build "cleanup(&decl)" for the destructor. */
3664 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3665 cleanup = build_tree_list (NULL_TREE, cleanup);
3666 cleanup = build_function_call (cleanup_decl, cleanup);
3668 /* Don't warn about decl unused; the cleanup uses it. */
3669 TREE_USED (decl) = 1;
3670 TREE_USED (cleanup_decl) = 1;
3672 /* Initialize EH, if we've been told to do so. */
3673 c_maybe_initialize_eh ();
3675 push_cleanup (decl, cleanup, false);
3680 /* Given a parsed parameter declaration, decode it into a PARM_DECL. */
3683 grokparm (const struct c_parm *parm)
3685 tree decl = grokdeclarator (parm->declarator, parm->specs, PARM, false,
3688 decl_attributes (&decl, parm->attrs, 0);
3693 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3694 and push that on the current scope. */
3697 push_parm_decl (const struct c_parm *parm)
3701 decl = grokdeclarator (parm->declarator, parm->specs, PARM, false, NULL);
3702 decl_attributes (&decl, parm->attrs, 0);
3704 decl = pushdecl (decl);
3706 finish_decl (decl, NULL_TREE, NULL_TREE);
3709 /* Mark all the parameter declarations to date as forward decls.
3710 Also diagnose use of this extension. */
3713 mark_forward_parm_decls (void)
3715 struct c_binding *b;
3717 if (pedantic && !current_scope->warned_forward_parm_decls)
3719 pedwarn ("ISO C forbids forward parameter declarations");
3720 current_scope->warned_forward_parm_decls = true;
3723 for (b = current_scope->bindings; b; b = b->prev)
3724 if (TREE_CODE (b->decl) == PARM_DECL)
3725 TREE_ASM_WRITTEN (b->decl) = 1;
3728 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3729 literal, which may be an incomplete array type completed by the
3730 initializer; INIT is a CONSTRUCTOR that initializes the compound
3734 build_compound_literal (tree type, tree init)
3736 /* We do not use start_decl here because we have a type, not a declarator;
3737 and do not use finish_decl because the decl should be stored inside
3738 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3743 if (type == error_mark_node)
3744 return error_mark_node;
3746 decl = build_decl (VAR_DECL, NULL_TREE, type);
3747 DECL_EXTERNAL (decl) = 0;
3748 TREE_PUBLIC (decl) = 0;
3749 TREE_STATIC (decl) = (current_scope == file_scope);
3750 DECL_CONTEXT (decl) = current_function_decl;
3751 TREE_USED (decl) = 1;
3752 TREE_TYPE (decl) = type;
3753 TREE_READONLY (decl) = TYPE_READONLY (type);
3754 store_init_value (decl, init);
3756 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3758 int failure = complete_array_type (&TREE_TYPE (decl),
3759 DECL_INITIAL (decl), true);
3760 gcc_assert (!failure);
3762 type = TREE_TYPE (decl);
3763 TREE_TYPE (DECL_INITIAL (decl)) = type;
3766 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3767 return error_mark_node;
3769 stmt = build_stmt (DECL_EXPR, decl);
3770 complit = build1 (COMPOUND_LITERAL_EXPR, type, stmt);
3771 TREE_SIDE_EFFECTS (complit) = 1;
3773 layout_decl (decl, 0);
3775 if (TREE_STATIC (decl))
3777 /* This decl needs a name for the assembler output. */
3778 set_compound_literal_name (decl);
3779 DECL_DEFER_OUTPUT (decl) = 1;
3780 DECL_COMDAT (decl) = 1;
3781 DECL_ARTIFICIAL (decl) = 1;
3782 DECL_IGNORED_P (decl) = 1;
3784 rest_of_decl_compilation (decl, 1, 0);
3790 /* Determine whether TYPE is a structure with a flexible array member,
3791 or a union containing such a structure (possibly recursively). */
3794 flexible_array_type_p (tree type)
3797 switch (TREE_CODE (type))
3800 x = TYPE_FIELDS (type);
3803 while (TREE_CHAIN (x) != NULL_TREE)
3805 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3806 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3807 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3808 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3812 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3814 if (flexible_array_type_p (TREE_TYPE (x)))
3823 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3824 replacing with appropriate values if they are invalid. */
3826 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3829 unsigned int max_width;
3830 unsigned HOST_WIDE_INT w;
3831 const char *name = orig_name ? orig_name: _("<anonymous>");
3833 /* Detect and ignore out of range field width and process valid
3835 if (!INTEGRAL_TYPE_P (TREE_TYPE (*width))
3836 || TREE_CODE (*width) != INTEGER_CST)
3838 error ("bit-field %qs width not an integer constant", name);
3839 *width = integer_one_node;
3843 constant_expression_warning (*width);
3844 if (tree_int_cst_sgn (*width) < 0)
3846 error ("negative width in bit-field %qs", name);
3847 *width = integer_one_node;
3849 else if (integer_zerop (*width) && orig_name)
3851 error ("zero width for bit-field %qs", name);
3852 *width = integer_one_node;
3856 /* Detect invalid bit-field type. */
3857 if (TREE_CODE (*type) != INTEGER_TYPE
3858 && TREE_CODE (*type) != BOOLEAN_TYPE
3859 && TREE_CODE (*type) != ENUMERAL_TYPE)
3861 error ("bit-field %qs has invalid type", name);
3862 *type = unsigned_type_node;
3865 type_mv = TYPE_MAIN_VARIANT (*type);
3867 && !in_system_header
3868 && type_mv != integer_type_node
3869 && type_mv != unsigned_type_node
3870 && type_mv != boolean_type_node)
3871 pedwarn ("type of bit-field %qs is a GCC extension", name);
3873 if (type_mv == boolean_type_node)
3874 max_width = CHAR_TYPE_SIZE;
3876 max_width = TYPE_PRECISION (*type);
3878 if (0 < compare_tree_int (*width, max_width))
3880 error ("width of %qs exceeds its type", name);
3882 *width = build_int_cst (NULL_TREE, w);
3885 w = tree_low_cst (*width, 1);
3887 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3889 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3891 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3892 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3893 warning (0, "%qs is narrower than values of its type", name);
3898 /* Given declspecs and a declarator,
3899 determine the name and type of the object declared
3900 and construct a ..._DECL node for it.
3901 (In one case we can return a ..._TYPE node instead.
3902 For invalid input we sometimes return 0.)
3904 DECLSPECS is a c_declspecs structure for the declaration specifiers.
3906 DECL_CONTEXT says which syntactic context this declaration is in:
3907 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3908 FUNCDEF for a function definition. Like NORMAL but a few different
3909 error messages in each case. Return value may be zero meaning
3910 this definition is too screwy to try to parse.
3911 PARM for a parameter declaration (either within a function prototype
3912 or before a function body). Make a PARM_DECL, or return void_type_node.
3913 TYPENAME if for a typename (in a cast or sizeof).
3914 Don't make a DECL node; just return the ..._TYPE node.
3915 FIELD for a struct or union field; make a FIELD_DECL.
3916 INITIALIZED is true if the decl has an initializer.
3917 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3918 representing the width of the bit-field.
3920 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3921 It may also be so in the PARM case, for a prototype where the
3922 argument type is specified but not the name.
3924 This function is where the complicated C meanings of `static'
3925 and `extern' are interpreted. */
3928 grokdeclarator (const struct c_declarator *declarator,
3929 struct c_declspecs *declspecs,
3930 enum decl_context decl_context, bool initialized, tree *width)
3932 tree type = declspecs->type;
3933 bool threadp = declspecs->thread_p;
3934 enum c_storage_class storage_class = declspecs->storage_class;
3938 int type_quals = TYPE_UNQUALIFIED;
3939 const char *name, *orig_name;
3940 tree typedef_type = 0;
3941 bool funcdef_flag = false;
3942 bool funcdef_syntax = false;
3943 int size_varies = 0;
3944 tree decl_attr = declspecs->decl_attr;
3945 int array_ptr_quals = TYPE_UNQUALIFIED;
3946 tree array_ptr_attrs = NULL_TREE;
3947 int array_parm_static = 0;
3948 bool array_parm_vla_unspec_p = false;
3949 tree returned_attrs = NULL_TREE;
3950 bool bitfield = width != NULL;
3952 struct c_arg_info *arg_info = 0;
3954 if (decl_context == FUNCDEF)
3955 funcdef_flag = true, decl_context = NORMAL;
3957 /* Look inside a declarator for the name being declared
3958 and get it as a string, for an error message. */
3960 const struct c_declarator *decl = declarator;
3969 funcdef_syntax = (decl->kind == cdk_function);
3970 decl = decl->declarator;
3974 decl = decl->declarator;
3979 name = IDENTIFIER_POINTER (decl->u.id);
3991 /* A function definition's declarator must have the form of
3992 a function declarator. */
3994 if (funcdef_flag && !funcdef_syntax)
3997 /* If this looks like a function definition, make it one,
3998 even if it occurs where parms are expected.
3999 Then store_parm_decls will reject it and not use it as a parm. */
4000 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
4001 decl_context = PARM;
4003 if (declspecs->deprecated_p && deprecated_state != DEPRECATED_SUPPRESS)
4004 warn_deprecated_use (declspecs->type);
4006 if ((decl_context == NORMAL || decl_context == FIELD)
4007 && current_scope == file_scope
4008 && variably_modified_type_p (type, NULL_TREE))
4010 error ("variably modified %qs at file scope", name);
4011 type = integer_type_node;
4014 typedef_type = type;
4015 size_varies = C_TYPE_VARIABLE_SIZE (type);
4017 /* Diagnose defaulting to "int". */
4019 if (declspecs->default_int_p && !in_system_header)
4021 /* Issue a warning if this is an ISO C 99 program or if
4022 -Wreturn-type and this is a function, or if -Wimplicit;
4023 prefer the former warning since it is more explicit. */
4024 if ((warn_implicit_int || warn_return_type || flag_isoc99)
4026 warn_about_return_type = 1;
4027 else if (warn_implicit_int || flag_isoc99)
4028 pedwarn_c99 ("type defaults to %<int%> in declaration of %qs", name);
4031 /* Adjust the type if a bit-field is being declared,
4032 -funsigned-bitfields applied and the type is not explicitly
4034 if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
4035 && TREE_CODE (type) == INTEGER_TYPE)
4036 type = c_common_unsigned_type (type);
4038 /* Figure out the type qualifiers for the declaration. There are
4039 two ways a declaration can become qualified. One is something
4040 like `const int i' where the `const' is explicit. Another is
4041 something like `typedef const int CI; CI i' where the type of the
4042 declaration contains the `const'. A third possibility is that
4043 there is a type qualifier on the element type of a typedefed
4044 array type, in which case we should extract that qualifier so
4045 that c_apply_type_quals_to_decls receives the full list of
4046 qualifiers to work with (C90 is not entirely clear about whether
4047 duplicate qualifiers should be diagnosed in this case, but it
4048 seems most appropriate to do so). */
4049 element_type = strip_array_types (type);
4050 constp = declspecs->const_p + TYPE_READONLY (element_type);
4051 restrictp = declspecs->restrict_p + TYPE_RESTRICT (element_type);
4052 volatilep = declspecs->volatile_p + TYPE_VOLATILE (element_type);
4053 if (pedantic && !flag_isoc99)
4056 pedwarn ("duplicate %<const%>");
4058 pedwarn ("duplicate %<restrict%>");
4060 pedwarn ("duplicate %<volatile%>");
4062 if (!flag_gen_aux_info && (TYPE_QUALS (element_type)))
4063 type = TYPE_MAIN_VARIANT (type);
4064 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4065 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4066 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4068 /* Warn about storage classes that are invalid for certain
4069 kinds of declarations (parameters, typenames, etc.). */
4073 || storage_class == csc_auto
4074 || storage_class == csc_register
4075 || storage_class == csc_typedef))
4077 if (storage_class == csc_auto
4078 && (pedantic || current_scope == file_scope))
4079 pedwarn ("function definition declared %<auto%>");
4080 if (storage_class == csc_register)
4081 error ("function definition declared %<register%>");
4082 if (storage_class == csc_typedef)
4083 error ("function definition declared %<typedef%>");
4085 error ("function definition declared %<__thread%>");
4087 if (storage_class == csc_auto
4088 || storage_class == csc_register
4089 || storage_class == csc_typedef)
4090 storage_class = csc_none;
4092 else if (decl_context != NORMAL && (storage_class != csc_none || threadp))
4094 if (decl_context == PARM && storage_class == csc_register)
4098 switch (decl_context)
4101 error ("storage class specified for structure field %qs",
4105 error ("storage class specified for parameter %qs", name);
4108 error ("storage class specified for typename");
4111 storage_class = csc_none;
4115 else if (storage_class == csc_extern
4119 /* 'extern' with initialization is invalid if not at file scope. */
4120 if (current_scope == file_scope)
4122 /* It is fine to have 'extern const' when compiling at C
4123 and C++ intersection. */
4124 if (!(warn_cxx_compat && constp))
4125 warning (0, "%qs initialized and declared %<extern%>", name);
4128 error ("%qs has both %<extern%> and initializer", name);
4130 else if (current_scope == file_scope)
4132 if (storage_class == csc_auto)
4133 error ("file-scope declaration of %qs specifies %<auto%>", name);
4134 if (pedantic && storage_class == csc_register)
4135 pedwarn ("file-scope declaration of %qs specifies %<register%>", name);
4139 if (storage_class == csc_extern && funcdef_flag)
4140 error ("nested function %qs declared %<extern%>", name);
4141 else if (threadp && storage_class == csc_none)
4143 error ("function-scope %qs implicitly auto and declared "
4150 /* Now figure out the structure of the declarator proper.
4151 Descend through it, creating more complex types, until we reach
4152 the declared identifier (or NULL_TREE, in an absolute declarator).
4153 At each stage we maintain an unqualified version of the type
4154 together with any qualifiers that should be applied to it with
4155 c_build_qualified_type; this way, array types including
4156 multidimensional array types are first built up in unqualified
4157 form and then the qualified form is created with
4158 TYPE_MAIN_VARIANT pointing to the unqualified form. */
4160 while (declarator && declarator->kind != cdk_id)
4162 if (type == error_mark_node)
4164 declarator = declarator->declarator;
4168 /* Each level of DECLARATOR is either a cdk_array (for ...[..]),
4169 a cdk_pointer (for *...),
4170 a cdk_function (for ...(...)),
4171 a cdk_attrs (for nested attributes),
4172 or a cdk_id (for the name being declared
4173 or the place in an absolute declarator
4174 where the name was omitted).
4175 For the last case, we have just exited the loop.
4177 At this point, TYPE is the type of elements of an array,
4178 or for a function to return, or for a pointer to point to.
4179 After this sequence of ifs, TYPE is the type of the
4180 array or function or pointer, and DECLARATOR has had its
4181 outermost layer removed. */
4183 if (array_ptr_quals != TYPE_UNQUALIFIED
4184 || array_ptr_attrs != NULL_TREE
4185 || array_parm_static)
4187 /* Only the innermost declarator (making a parameter be of
4188 array type which is converted to pointer type)
4189 may have static or type qualifiers. */
4190 error ("static or type qualifiers in non-parameter array declarator");
4191 array_ptr_quals = TYPE_UNQUALIFIED;
4192 array_ptr_attrs = NULL_TREE;
4193 array_parm_static = 0;
4196 switch (declarator->kind)
4200 /* A declarator with embedded attributes. */
4201 tree attrs = declarator->u.attrs;
4202 const struct c_declarator *inner_decl;
4204 declarator = declarator->declarator;
4205 inner_decl = declarator;
4206 while (inner_decl->kind == cdk_attrs)
4207 inner_decl = inner_decl->declarator;
4208 if (inner_decl->kind == cdk_id)
4209 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4210 else if (inner_decl->kind == cdk_function)
4211 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4212 else if (inner_decl->kind == cdk_array)
4213 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4214 returned_attrs = decl_attributes (&type,
4215 chainon (returned_attrs, attrs),
4221 tree itype = NULL_TREE;
4222 tree size = declarator->u.array.dimen;
4223 /* The index is a signed object `sizetype' bits wide. */
4224 tree index_type = c_common_signed_type (sizetype);
4226 array_ptr_quals = declarator->u.array.quals;
4227 array_ptr_attrs = declarator->u.array.attrs;
4228 array_parm_static = declarator->u.array.static_p;
4229 array_parm_vla_unspec_p = declarator->u.array.vla_unspec_p;
4231 declarator = declarator->declarator;
4233 /* Check for some types that there cannot be arrays of. */
4235 if (VOID_TYPE_P (type))
4237 error ("declaration of %qs as array of voids", name);
4238 type = error_mark_node;
4241 if (TREE_CODE (type) == FUNCTION_TYPE)
4243 error ("declaration of %qs as array of functions", name);
4244 type = error_mark_node;
4247 if (pedantic && !in_system_header && flexible_array_type_p (type))
4248 pedwarn ("invalid use of structure with flexible array member");
4250 if (size == error_mark_node)
4251 type = error_mark_node;
4253 if (type == error_mark_node)
4256 /* If size was specified, set ITYPE to a range-type for
4257 that size. Otherwise, ITYPE remains null. finish_decl
4258 may figure it out from an initial value. */
4262 /* Strip NON_LVALUE_EXPRs since we aren't using as an
4264 STRIP_TYPE_NOPS (size);
4266 if (!INTEGRAL_TYPE_P (TREE_TYPE (size)))
4268 error ("size of array %qs has non-integer type", name);
4269 size = integer_one_node;
4272 if (pedantic && integer_zerop (size))
4273 pedwarn ("ISO C forbids zero-size array %qs", name);
4275 if (TREE_CODE (size) == INTEGER_CST)
4277 constant_expression_warning (size);
4278 if (tree_int_cst_sgn (size) < 0)
4280 error ("size of array %qs is negative", name);
4281 size = integer_one_node;
4284 else if ((decl_context == NORMAL || decl_context == FIELD)
4285 && current_scope == file_scope)
4287 error ("variably modified %qs at file scope", name);
4288 size = integer_one_node;
4292 /* Make sure the array size remains visibly
4293 nonconstant even if it is (eg) a const variable
4294 with known value. */
4297 if (!flag_isoc99 && pedantic)
4299 if (TREE_CONSTANT (size))
4300 pedwarn ("ISO C90 forbids array %qs whose size "
4301 "can%'t be evaluated",
4304 pedwarn ("ISO C90 forbids variable-size array %qs",
4309 if (integer_zerop (size))
4311 /* A zero-length array cannot be represented with
4312 an unsigned index type, which is what we'll
4313 get with build_index_type. Create an
4314 open-ended range instead. */
4315 itype = build_range_type (sizetype, size, NULL_TREE);
4319 /* Arrange for the SAVE_EXPR on the inside of the
4320 MINUS_EXPR, which allows the -1 to get folded
4321 with the +1 that happens when building TYPE_SIZE. */
4323 size = variable_size (size);
4325 /* Compute the maximum valid index, that is, size
4326 - 1. Do the calculation in index_type, so that
4327 if it is a variable the computations will be
4328 done in the proper mode. */
4329 itype = fold_build2 (MINUS_EXPR, index_type,
4330 convert (index_type, size),
4331 convert (index_type,
4334 /* If that overflowed, the array is too big. ???
4335 While a size of INT_MAX+1 technically shouldn't
4336 cause an overflow (because we subtract 1), the
4337 overflow is recorded during the conversion to
4338 index_type, before the subtraction. Handling
4339 this case seems like an unnecessary
4341 if (TREE_CODE (itype) == INTEGER_CST
4342 && TREE_OVERFLOW (itype))
4344 error ("size of array %qs is too large", name);
4345 type = error_mark_node;
4349 itype = build_index_type (itype);
4352 else if (decl_context == FIELD)
4354 if (pedantic && !flag_isoc99 && !in_system_header)
4355 pedwarn ("ISO C90 does not support flexible array members");
4357 /* ISO C99 Flexible array members are effectively
4358 identical to GCC's zero-length array extension. */
4359 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4361 else if (decl_context == PARM)
4363 if (array_parm_vla_unspec_p)
4368 error ("%<[*]%> not allowed in other than a declaration");
4371 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4375 else if (decl_context == TYPENAME)
4377 if (array_parm_vla_unspec_p)
4379 /* The error is printed elsewhere. We use this to
4380 avoid messing up with incomplete array types of
4381 the same type, that would otherwise be modified
4383 itype = build_range_type (sizetype, size_zero_node,
4388 /* Complain about arrays of incomplete types. */
4389 if (!COMPLETE_TYPE_P (type))
4391 error ("array type has incomplete element type");
4392 type = error_mark_node;
4395 /* When itype is NULL, a shared incomplete array type is
4396 returned for all array of a given type. Elsewhere we
4397 make sure we don't complete that type before copying
4398 it, but here we want to make sure we don't ever
4399 modify the shared type, so we gcc_assert (itype)
4401 type = build_array_type (type, itype);
4403 if (type != error_mark_node)
4407 /* It is ok to modify type here even if itype is
4408 NULL: if size_varies, we're in a
4409 multi-dimensional array and the inner type has
4410 variable size, so the enclosing shared array type
4412 if (size && TREE_CODE (size) == INTEGER_CST)
4414 = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4415 C_TYPE_VARIABLE_SIZE (type) = 1;
4418 /* The GCC extension for zero-length arrays differs from
4419 ISO flexible array members in that sizeof yields
4421 if (size && integer_zerop (size))
4424 TYPE_SIZE (type) = bitsize_zero_node;
4425 TYPE_SIZE_UNIT (type) = size_zero_node;
4427 if (array_parm_vla_unspec_p)
4430 /* The type is complete. C99 6.7.5.2p4 */
4431 TYPE_SIZE (type) = bitsize_zero_node;
4432 TYPE_SIZE_UNIT (type) = size_zero_node;
4436 if (decl_context != PARM
4437 && (array_ptr_quals != TYPE_UNQUALIFIED
4438 || array_ptr_attrs != NULL_TREE
4439 || array_parm_static))
4441 error ("static or type qualifiers in non-parameter array declarator");
4442 array_ptr_quals = TYPE_UNQUALIFIED;
4443 array_ptr_attrs = NULL_TREE;
4444 array_parm_static = 0;
4450 /* Say it's a definition only for the declarator closest
4451 to the identifier, apart possibly from some
4453 bool really_funcdef = false;
4457 const struct c_declarator *t = declarator->declarator;
4458 while (t->kind == cdk_attrs)
4460 really_funcdef = (t->kind == cdk_id);
4463 /* Declaring a function type. Make sure we have a valid
4464 type for the function to return. */
4465 if (type == error_mark_node)
4470 /* Warn about some types functions can't return. */
4471 if (TREE_CODE (type) == FUNCTION_TYPE)
4473 error ("%qs declared as function returning a function", name);
4474 type = integer_type_node;
4476 if (TREE_CODE (type) == ARRAY_TYPE)
4478 error ("%qs declared as function returning an array", name);
4479 type = integer_type_node;
4482 /* Construct the function type and go to the next
4483 inner layer of declarator. */
4484 arg_info = declarator->u.arg_info;
4485 arg_types = grokparms (arg_info, really_funcdef);
4487 put_pending_sizes (arg_info->pending_sizes);
4489 /* Type qualifiers before the return type of the function
4490 qualify the return type, not the function type. */
4493 /* Type qualifiers on a function return type are
4494 normally permitted by the standard but have no
4495 effect, so give a warning at -Wreturn-type.
4496 Qualifiers on a void return type are banned on
4497 function definitions in ISO C; GCC used to used
4498 them for noreturn functions. */
4499 if (VOID_TYPE_P (type) && really_funcdef)
4500 pedwarn ("function definition has qualified void return type");
4502 warning (OPT_Wreturn_type,
4503 "type qualifiers ignored on function return type");
4505 type = c_build_qualified_type (type, type_quals);
4507 type_quals = TYPE_UNQUALIFIED;
4509 type = build_function_type (type, arg_types);
4510 declarator = declarator->declarator;
4512 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4513 the formal parameter list of this FUNCTION_TYPE to point to
4514 the FUNCTION_TYPE node itself. */
4518 for (link = arg_info->tags;
4520 link = TREE_CHAIN (link))
4521 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4527 /* Merge any constancy or volatility into the target type
4530 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4532 pedwarn ("ISO C forbids qualified function types");
4534 type = c_build_qualified_type (type, type_quals);
4537 /* When the pointed-to type involves components of variable size,
4538 care must be taken to ensure that the size evaluation code is
4539 emitted early enough to dominate all the possible later uses
4540 and late enough for the variables on which it depends to have
4543 This is expected to happen automatically when the pointed-to
4544 type has a name/declaration of it's own, but special attention
4545 is required if the type is anonymous.
4547 We handle the NORMAL and FIELD contexts here by attaching an
4548 artificial TYPE_DECL to such pointed-to type. This forces the
4549 sizes evaluation at a safe point and ensures it is not deferred
4550 until e.g. within a deeper conditional context.
4552 We expect nothing to be needed here for PARM or TYPENAME.
4553 Pushing a TYPE_DECL at this point for TYPENAME would actually
4554 be incorrect, as we might be in the middle of an expression
4555 with side effects on the pointed-to type size "arguments" prior
4556 to the pointer declaration point and the fake TYPE_DECL in the
4557 enclosing context would force the size evaluation prior to the
4560 if (!TYPE_NAME (type)
4561 && (decl_context == NORMAL || decl_context == FIELD)
4562 && variably_modified_type_p (type, NULL_TREE))
4564 tree decl = build_decl (TYPE_DECL, NULL_TREE, type);
4565 DECL_ARTIFICIAL (decl) = 1;
4567 finish_decl (decl, NULL_TREE, NULL_TREE);
4568 TYPE_NAME (type) = decl;
4571 type = build_pointer_type (type);
4573 /* Process type qualifiers (such as const or volatile)
4574 that were given inside the `*'. */
4575 type_quals = declarator->u.pointer_quals;
4577 declarator = declarator->declarator;
4585 /* Now TYPE has the actual type, apart from any qualifiers in
4588 /* Check the type and width of a bit-field. */
4590 check_bitfield_type_and_width (&type, width, orig_name);
4592 /* Did array size calculations overflow? */
4594 if (TREE_CODE (type) == ARRAY_TYPE
4595 && COMPLETE_TYPE_P (type)
4596 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
4597 && TREE_OVERFLOW (TYPE_SIZE_UNIT (type)))
4599 error ("size of array %qs is too large", name);
4600 /* If we proceed with the array type as it is, we'll eventually
4601 crash in tree_low_cst(). */
4602 type = error_mark_node;
4605 /* If this is declaring a typedef name, return a TYPE_DECL. */
4607 if (storage_class == csc_typedef)
4610 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4612 pedwarn ("ISO C forbids qualified function types");
4614 type = c_build_qualified_type (type, type_quals);
4615 decl = build_decl (TYPE_DECL, declarator->u.id, type);
4616 if (declspecs->explicit_signed_p)
4617 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4618 decl_attributes (&decl, returned_attrs, 0);
4619 if (declspecs->inline_p)
4620 pedwarn ("typedef %q+D declared %<inline%>", decl);
4624 /* If this is a type name (such as, in a cast or sizeof),
4625 compute the type and return it now. */
4627 if (decl_context == TYPENAME)
4629 /* Note that the grammar rejects storage classes in typenames
4631 gcc_assert (storage_class == csc_none && !threadp
4632 && !declspecs->inline_p);
4633 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4635 pedwarn ("ISO C forbids const or volatile function types");
4637 type = c_build_qualified_type (type, type_quals);
4638 decl_attributes (&type, returned_attrs, 0);
4642 if (pedantic && decl_context == FIELD
4643 && variably_modified_type_p (type, NULL_TREE))
4646 pedwarn ("a member of a structure or union cannot have a variably modified type");
4649 /* Aside from typedefs and type names (handle above),
4650 `void' at top level (not within pointer)
4651 is allowed only in public variables.
4652 We don't complain about parms either, but that is because
4653 a better error message can be made later. */
4655 if (VOID_TYPE_P (type) && decl_context != PARM
4656 && !((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4657 && (storage_class == csc_extern
4658 || (current_scope == file_scope
4659 && !(storage_class == csc_static
4660 || storage_class == csc_register)))))
4662 error ("variable or field %qs declared void", name);
4663 type = integer_type_node;
4666 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4667 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4672 if (decl_context == PARM)
4674 tree type_as_written;
4677 /* A parameter declared as an array of T is really a pointer to T.
4678 One declared as a function is really a pointer to a function. */
4680 if (TREE_CODE (type) == ARRAY_TYPE)
4682 /* Transfer const-ness of array into that of type pointed to. */
4683 type = TREE_TYPE (type);
4685 type = c_build_qualified_type (type, type_quals);
4686 type = build_pointer_type (type);
4687 type_quals = array_ptr_quals;
4689 /* We don't yet implement attributes in this context. */
4690 if (array_ptr_attrs != NULL_TREE)
4691 warning (OPT_Wattributes,
4692 "attributes in parameter array declarator ignored");
4696 else if (TREE_CODE (type) == FUNCTION_TYPE)
4698 if (pedantic && type_quals)
4699 pedwarn ("ISO C forbids qualified function types");
4701 type = c_build_qualified_type (type, type_quals);
4702 type = build_pointer_type (type);
4703 type_quals = TYPE_UNQUALIFIED;
4705 else if (type_quals)
4706 type = c_build_qualified_type (type, type_quals);
4708 type_as_written = type;
4710 decl = build_decl (PARM_DECL, declarator->u.id, type);
4712 C_DECL_VARIABLE_SIZE (decl) = 1;
4714 /* Compute the type actually passed in the parmlist,
4715 for the case where there is no prototype.
4716 (For example, shorts and chars are passed as ints.)
4717 When there is a prototype, this is overridden later. */
4719 if (type == error_mark_node)
4720 promoted_type = type;
4722 promoted_type = c_type_promotes_to (type);
4724 DECL_ARG_TYPE (decl) = promoted_type;
4725 if (declspecs->inline_p)
4726 pedwarn ("parameter %q+D declared %<inline%>", decl);
4728 else if (decl_context == FIELD)
4730 /* Note that the grammar rejects storage classes in typenames
4732 gcc_assert (storage_class == csc_none && !threadp
4733 && !declspecs->inline_p);
4735 /* Structure field. It may not be a function. */
4737 if (TREE_CODE (type) == FUNCTION_TYPE)
4739 error ("field %qs declared as a function", name);
4740 type = build_pointer_type (type);
4742 else if (TREE_CODE (type) != ERROR_MARK
4743 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4745 error ("field %qs has incomplete type", name);
4746 type = error_mark_node;
4748 type = c_build_qualified_type (type, type_quals);
4749 decl = build_decl (FIELD_DECL, declarator->u.id, type);
4750 DECL_NONADDRESSABLE_P (decl) = bitfield;
4753 C_DECL_VARIABLE_SIZE (decl) = 1;
4755 else if (TREE_CODE (type) == FUNCTION_TYPE)
4757 if (storage_class == csc_register || threadp)
4759 error ("invalid storage class for function %qs", name);
4761 else if (current_scope != file_scope)
4763 /* Function declaration not at file scope. Storage
4764 classes other than `extern' are not allowed, C99
4765 6.7.1p5, and `extern' makes no difference. However,
4766 GCC allows 'auto', perhaps with 'inline', to support
4767 nested functions. */
4768 if (storage_class == csc_auto)
4771 pedwarn ("invalid storage class for function %qs", name);
4773 else if (storage_class == csc_static)
4775 error ("invalid storage class for function %qs", name);
4777 storage_class = declspecs->storage_class = csc_none;
4783 decl = build_decl (FUNCTION_DECL, declarator->u.id, type);
4784 decl = build_decl_attribute_variant (decl, decl_attr);
4786 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
4788 if (pedantic && type_quals && !DECL_IN_SYSTEM_HEADER (decl))
4789 pedwarn ("ISO C forbids qualified function types");
4791 /* GNU C interprets a volatile-qualified function type to indicate
4792 that the function does not return. */
4793 if ((type_quals & TYPE_QUAL_VOLATILE)
4794 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4795 warning (0, "%<noreturn%> function returns non-void value");
4797 /* Every function declaration is an external reference
4798 (DECL_EXTERNAL) except for those which are not at file
4799 scope and are explicitly declared "auto". This is
4800 forbidden by standard C (C99 6.7.1p5) and is interpreted by
4801 GCC to signify a forward declaration of a nested function. */
4802 if (storage_class == csc_auto && current_scope != file_scope)
4803 DECL_EXTERNAL (decl) = 0;
4804 /* In C99, a function which is declared 'inline' with 'extern'
4805 is not an external reference (which is confusing). It
4806 means that the later definition of the function must be output
4807 in this file, C99 6.7.4p6. In GNU C89, a function declared
4808 'extern inline' is an external reference. */
4809 else if (declspecs->inline_p && storage_class != csc_static)
4810 DECL_EXTERNAL (decl) = ((storage_class == csc_extern)
4811 == flag_gnu89_inline);
4813 DECL_EXTERNAL (decl) = !initialized;
4815 /* Record absence of global scope for `static' or `auto'. */
4817 = !(storage_class == csc_static || storage_class == csc_auto);
4819 /* For a function definition, record the argument information
4820 block where store_parm_decls will look for it. */
4822 current_function_arg_info = arg_info;
4824 if (declspecs->default_int_p)
4825 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4827 /* Record presence of `inline', if it is reasonable. */
4828 if (flag_hosted && MAIN_NAME_P (declarator->u.id))
4830 if (declspecs->inline_p)
4831 pedwarn ("cannot inline function %<main%>");
4833 else if (declspecs->inline_p)
4835 /* Record that the function is declared `inline'. */
4836 DECL_DECLARED_INLINE_P (decl) = 1;
4838 /* Do not mark bare declarations as DECL_INLINE. Doing so
4839 in the presence of multiple declarations can result in
4840 the abstract origin pointing between the declarations,
4841 which will confuse dwarf2out. */
4843 DECL_INLINE (decl) = 1;
4845 /* If -finline-functions, assume it can be inlined. This does
4846 two things: let the function be deferred until it is actually
4847 needed, and let dwarf2 know that the function is inlinable. */
4848 else if (flag_inline_trees == 2 && initialized)
4849 DECL_INLINE (decl) = 1;
4853 /* It's a variable. */
4854 /* An uninitialized decl with `extern' is a reference. */
4855 int extern_ref = !initialized && storage_class == csc_extern;
4857 type = c_build_qualified_type (type, type_quals);
4859 /* C99 6.2.2p7: It is invalid (compile-time undefined
4860 behavior) to create an 'extern' declaration for a
4861 variable if there is a global declaration that is
4862 'static' and the global declaration is not visible.
4863 (If the static declaration _is_ currently visible,
4864 the 'extern' declaration is taken to refer to that decl.) */
4865 if (extern_ref && current_scope != file_scope)
4867 tree global_decl = identifier_global_value (declarator->u.id);
4868 tree visible_decl = lookup_name (declarator->u.id);
4871 && global_decl != visible_decl
4872 && TREE_CODE (global_decl) == VAR_DECL
4873 && !TREE_PUBLIC (global_decl))
4874 error ("variable previously declared %<static%> redeclared "
4878 decl = build_decl (VAR_DECL, declarator->u.id, type);
4879 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4881 C_DECL_VARIABLE_SIZE (decl) = 1;
4883 if (declspecs->inline_p)
4884 pedwarn ("variable %q+D declared %<inline%>", decl);
4886 /* At file scope, an initialized extern declaration may follow
4887 a static declaration. In that case, DECL_EXTERNAL will be
4888 reset later in start_decl. */
4889 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4891 /* At file scope, the presence of a `static' or `register' storage
4892 class specifier, or the absence of all storage class specifiers
4893 makes this declaration a definition (perhaps tentative). Also,
4894 the absence of `static' makes it public. */
4895 if (current_scope == file_scope)
4897 TREE_PUBLIC (decl) = storage_class != csc_static;
4898 TREE_STATIC (decl) = !extern_ref;
4900 /* Not at file scope, only `static' makes a static definition. */
4903 TREE_STATIC (decl) = (storage_class == csc_static);
4904 TREE_PUBLIC (decl) = extern_ref;
4908 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
4911 if (storage_class == csc_extern
4912 && variably_modified_type_p (type, NULL_TREE))
4915 error ("object with variably modified type must have no linkage");
4918 /* Record `register' declaration for warnings on &
4919 and in case doing stupid register allocation. */
4921 if (storage_class == csc_register)
4923 C_DECL_REGISTER (decl) = 1;
4924 DECL_REGISTER (decl) = 1;
4927 /* Record constancy and volatility. */
4928 c_apply_type_quals_to_decl (type_quals, decl);
4930 /* If a type has volatile components, it should be stored in memory.
4931 Otherwise, the fact that those components are volatile
4932 will be ignored, and would even crash the compiler.
4933 Of course, this only makes sense on VAR,PARM, and RESULT decl's. */
4934 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl))
4935 && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
4936 || TREE_CODE (decl) == RESULT_DECL))
4938 /* It is not an error for a structure with volatile fields to
4939 be declared register, but reset DECL_REGISTER since it
4940 cannot actually go in a register. */
4941 int was_reg = C_DECL_REGISTER (decl);
4942 C_DECL_REGISTER (decl) = 0;
4943 DECL_REGISTER (decl) = 0;
4944 c_mark_addressable (decl);
4945 C_DECL_REGISTER (decl) = was_reg;
4948 /* This is the earliest point at which we might know the assembler
4949 name of a variable. Thus, if it's known before this, die horribly. */
4950 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl));
4952 decl_attributes (&decl, returned_attrs, 0);
4958 /* Decode the parameter-list info for a function type or function definition.
4959 The argument is the value returned by `get_parm_info' (or made in c-parse.c
4960 if there is an identifier list instead of a parameter decl list).
4961 These two functions are separate because when a function returns
4962 or receives functions then each is called multiple times but the order
4963 of calls is different. The last call to `grokparms' is always the one
4964 that contains the formal parameter names of a function definition.
4966 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4968 FUNCDEF_FLAG is true for a function definition, false for
4969 a mere declaration. A nonempty identifier-list gets an error message
4970 when FUNCDEF_FLAG is false. */
4973 grokparms (struct c_arg_info *arg_info, bool funcdef_flag)
4975 tree arg_types = arg_info->types;
4977 if (funcdef_flag && arg_info->had_vla_unspec)
4979 /* A function definition isn't function prototype scope C99 6.2.1p4. */
4981 error ("%<[*]%> not allowed in other than function prototype scope");
4984 if (arg_types == 0 && !funcdef_flag && !in_system_header)
4985 warning (OPT_Wstrict_prototypes,
4986 "function declaration isn%'t a prototype");
4988 if (arg_types == error_mark_node)
4989 return 0; /* don't set TYPE_ARG_TYPES in this case */
4991 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
4994 pedwarn ("parameter names (without types) in function declaration");
4996 arg_info->parms = arg_info->types;
4997 arg_info->types = 0;
5002 tree parm, type, typelt;
5003 unsigned int parmno;
5005 /* If there is a parameter of incomplete type in a definition,
5006 this is an error. In a declaration this is valid, and a
5007 struct or union type may be completed later, before any calls
5008 or definition of the function. In the case where the tag was
5009 first declared within the parameter list, a warning has
5010 already been given. If a parameter has void type, then
5011 however the function cannot be defined or called, so
5014 for (parm = arg_info->parms, typelt = arg_types, parmno = 1;
5016 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
5018 type = TREE_VALUE (typelt);
5019 if (type == error_mark_node)
5022 if (!COMPLETE_TYPE_P (type))
5026 if (DECL_NAME (parm))
5027 error ("parameter %u (%q+D) has incomplete type",
5030 error ("%Jparameter %u has incomplete type",
5033 TREE_VALUE (typelt) = error_mark_node;
5034 TREE_TYPE (parm) = error_mark_node;
5036 else if (VOID_TYPE_P (type))
5038 if (DECL_NAME (parm))
5039 warning (0, "parameter %u (%q+D) has void type",
5042 warning (0, "%Jparameter %u has void type",
5047 if (DECL_NAME (parm) && TREE_USED (parm))
5048 warn_if_shadowing (parm);
5054 /* Take apart the current scope and return a c_arg_info structure with
5055 info on a parameter list just parsed.
5057 This structure is later fed to 'grokparms' and 'store_parm_decls'.
5059 ELLIPSIS being true means the argument list ended in '...' so don't
5060 append a sentinel (void_list_node) to the end of the type-list. */
5063 get_parm_info (bool ellipsis)
5065 struct c_binding *b = current_scope->bindings;
5066 struct c_arg_info *arg_info = XOBNEW (&parser_obstack,
5073 static bool explained_incomplete_types = false;
5074 bool gave_void_only_once_err = false;
5076 arg_info->parms = 0;
5078 arg_info->types = 0;
5079 arg_info->others = 0;
5080 arg_info->pending_sizes = 0;
5081 arg_info->had_vla_unspec = current_scope->had_vla_unspec;
5083 /* The bindings in this scope must not get put into a block.
5084 We will take care of deleting the binding nodes. */
5085 current_scope->bindings = 0;
5087 /* This function is only called if there was *something* on the
5091 /* A parameter list consisting solely of 'void' indicates that the
5092 function takes no arguments. But if the 'void' is qualified
5093 (by 'const' or 'volatile'), or has a storage class specifier
5094 ('register'), then the behavior is undefined; issue an error.
5095 Typedefs for 'void' are OK (see DR#157). */
5096 if (b->prev == 0 /* one binding */
5097 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
5098 && !DECL_NAME (b->decl) /* anonymous */
5099 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
5101 if (TREE_THIS_VOLATILE (b->decl)
5102 || TREE_READONLY (b->decl)
5103 || C_DECL_REGISTER (b->decl))
5104 error ("%<void%> as only parameter may not be qualified");
5106 /* There cannot be an ellipsis. */
5108 error ("%<void%> must be the only parameter");
5110 arg_info->types = void_list_node;
5115 types = void_list_node;
5117 /* Break up the bindings list into parms, tags, types, and others;
5118 apply sanity checks; purge the name-to-decl bindings. */
5121 tree decl = b->decl;
5122 tree type = TREE_TYPE (decl);
5123 const char *keyword;
5125 switch (TREE_CODE (decl))
5130 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5131 I_SYMBOL_BINDING (b->id) = b->shadowed;
5134 /* Check for forward decls that never got their actual decl. */
5135 if (TREE_ASM_WRITTEN (decl))
5136 error ("parameter %q+D has just a forward declaration", decl);
5137 /* Check for (..., void, ...) and issue an error. */
5138 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
5140 if (!gave_void_only_once_err)
5142 error ("%<void%> must be the only parameter");
5143 gave_void_only_once_err = true;
5148 /* Valid parameter, add it to the list. */
5149 TREE_CHAIN (decl) = parms;
5152 /* Since there is a prototype, args are passed in their
5153 declared types. The back end may override this later. */
5154 DECL_ARG_TYPE (decl) = type;
5155 types = tree_cons (0, type, types);
5159 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
5160 case UNION_TYPE: keyword = "union"; goto tag;
5161 case RECORD_TYPE: keyword = "struct"; goto tag;
5163 /* Types may not have tag-names, in which case the type
5164 appears in the bindings list with b->id NULL. */
5167 gcc_assert (I_TAG_BINDING (b->id) == b);
5168 I_TAG_BINDING (b->id) = b->shadowed;
5171 /* Warn about any struct, union or enum tags defined in a
5172 parameter list. The scope of such types is limited to
5173 the parameter list, which is rarely if ever desirable
5174 (it's impossible to call such a function with type-
5175 correct arguments). An anonymous union parm type is
5176 meaningful as a GNU extension, so don't warn for that. */
5177 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
5180 /* The %s will be one of 'struct', 'union', or 'enum'. */
5181 warning (0, "%<%s %E%> declared inside parameter list",
5184 /* The %s will be one of 'struct', 'union', or 'enum'. */
5185 warning (0, "anonymous %s declared inside parameter list",
5188 if (!explained_incomplete_types)
5190 warning (0, "its scope is only this definition or declaration,"
5191 " which is probably not what you want");
5192 explained_incomplete_types = true;
5196 tags = tree_cons (b->id, decl, tags);
5202 /* CONST_DECLs appear here when we have an embedded enum,
5203 and TYPE_DECLs appear here when we have an embedded struct
5204 or union. No warnings for this - we already warned about the
5205 type itself. FUNCTION_DECLs appear when there is an implicit
5206 function declaration in the parameter list. */
5208 TREE_CHAIN (decl) = others;
5213 /* error_mark_node appears here when we have an undeclared
5214 variable. Just throw it away. */
5217 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5218 I_SYMBOL_BINDING (b->id) = b->shadowed;
5222 /* Other things that might be encountered. */
5229 b = free_binding_and_advance (b);
5232 arg_info->parms = parms;
5233 arg_info->tags = tags;
5234 arg_info->types = types;
5235 arg_info->others = others;
5236 arg_info->pending_sizes = get_pending_sizes ();
5240 /* Get the struct, enum or union (CODE says which) with tag NAME.
5241 Define the tag as a forward-reference if it is not defined.
5242 Return a c_typespec structure for the type specifier. */
5245 parser_xref_tag (enum tree_code code, tree name)
5247 struct c_typespec ret;
5248 /* If a cross reference is requested, look up the type
5249 already defined for this tag and return it. */
5251 tree ref = lookup_tag (code, name, 0);
5252 /* If this is the right type of tag, return what we found.
5253 (This reference will be shadowed by shadow_tag later if appropriate.)
5254 If this is the wrong type of tag, do not return it. If it was the
5255 wrong type in the same scope, we will have had an error
5256 message already; if in a different scope and declaring
5257 a name, pending_xref_error will give an error message; but if in a
5258 different scope and not declaring a name, this tag should
5259 shadow the previous declaration of a different type of tag, and
5260 this would not work properly if we return the reference found.
5261 (For example, with "struct foo" in an outer scope, "union foo;"
5262 must shadow that tag with a new one of union type.) */
5263 ret.kind = (ref ? ctsk_tagref : ctsk_tagfirstref);
5264 if (ref && TREE_CODE (ref) == code)
5270 /* If no such tag is yet defined, create a forward-reference node
5271 and record it as the "definition".
5272 When a real declaration of this type is found,
5273 the forward-reference will be altered into a real type. */
5275 ref = make_node (code);
5276 if (code == ENUMERAL_TYPE)
5278 /* Give the type a default layout like unsigned int
5279 to avoid crashing if it does not get defined. */
5280 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5281 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5282 TYPE_USER_ALIGN (ref) = 0;
5283 TYPE_UNSIGNED (ref) = 1;
5284 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5285 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5286 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5289 pushtag (name, ref);
5295 /* Get the struct, enum or union (CODE says which) with tag NAME.
5296 Define the tag as a forward-reference if it is not defined.
5297 Return a tree for the type. */
5300 xref_tag (enum tree_code code, tree name)
5302 return parser_xref_tag (code, name).spec;
5305 /* Make sure that the tag NAME is defined *in the current scope*
5306 at least as a forward reference.
5307 CODE says which kind of tag NAME ought to be. */
5310 start_struct (enum tree_code code, tree name)
5312 /* If there is already a tag defined at this scope
5313 (as a forward reference), just return it. */
5318 ref = lookup_tag (code, name, 1);
5319 if (ref && TREE_CODE (ref) == code)
5321 if (TYPE_SIZE (ref))
5323 if (code == UNION_TYPE)
5324 error ("redefinition of %<union %E%>", name);
5326 error ("redefinition of %<struct %E%>", name);
5328 else if (C_TYPE_BEING_DEFINED (ref))
5330 if (code == UNION_TYPE)
5331 error ("nested redefinition of %<union %E%>", name);
5333 error ("nested redefinition of %<struct %E%>", name);
5334 /* Don't create structures that contain themselves. */
5339 /* Otherwise create a forward-reference just so the tag is in scope. */
5341 if (ref == NULL_TREE || TREE_CODE (ref) != code)
5343 ref = make_node (code);
5344 pushtag (name, ref);
5347 C_TYPE_BEING_DEFINED (ref) = 1;
5348 TYPE_PACKED (ref) = flag_pack_struct;
5352 /* Process the specs, declarator and width (NULL if omitted)
5353 of a structure component, returning a FIELD_DECL node.
5354 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
5356 This is done during the parsing of the struct declaration.
5357 The FIELD_DECL nodes are chained together and the lot of them
5358 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5361 grokfield (struct c_declarator *declarator, struct c_declspecs *declspecs,
5366 if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE
5367 && width == NULL_TREE)
5369 /* This is an unnamed decl.
5371 If we have something of the form "union { list } ;" then this
5372 is the anonymous union extension. Similarly for struct.
5374 If this is something of the form "struct foo;", then
5375 If MS extensions are enabled, this is handled as an
5377 Otherwise this is a forward declaration of a structure tag.
5379 If this is something of the form "foo;" and foo is a TYPE_DECL, then
5380 If MS extensions are enabled and foo names a structure, then
5381 again this is an anonymous struct.
5382 Otherwise this is an error.
5384 Oh what a horrid tangled web we weave. I wonder if MS consciously
5385 took this from Plan 9 or if it was an accident of implementation
5386 that took root before someone noticed the bug... */
5388 tree type = declspecs->type;
5389 bool type_ok = (TREE_CODE (type) == RECORD_TYPE
5390 || TREE_CODE (type) == UNION_TYPE);
5394 && (flag_ms_extensions || !declspecs->typedef_p))
5396 if (flag_ms_extensions)
5400 else if (TYPE_NAME (type) == NULL)
5407 pedwarn ("declaration does not declare anything");
5411 pedwarn ("ISO C doesn%'t support unnamed structs/unions");
5414 value = grokdeclarator (declarator, declspecs, FIELD, false,
5415 width ? &width : NULL);
5417 finish_decl (value, NULL_TREE, NULL_TREE);
5418 DECL_INITIAL (value) = width;
5423 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5424 the list such that this does not present a problem later. */
5427 detect_field_duplicates (tree fieldlist)
5432 /* First, see if there are more than "a few" fields.
5433 This is trivially true if there are zero or one fields. */
5436 x = TREE_CHAIN (fieldlist);
5442 } while (timeout > 0 && x);
5444 /* If there were "few" fields, avoid the overhead of allocating
5445 a hash table. Instead just do the nested traversal thing. */
5448 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5451 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5452 if (DECL_NAME (y) == DECL_NAME (x))
5454 error ("duplicate member %q+D", x);
5455 DECL_NAME (x) = NULL_TREE;
5461 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5464 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5465 if ((y = DECL_NAME (x)) != 0)
5467 slot = htab_find_slot (htab, y, INSERT);
5470 error ("duplicate member %q+D", x);
5471 DECL_NAME (x) = NULL_TREE;
5480 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5481 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5482 ATTRIBUTES are attributes to be applied to the structure. */
5485 finish_struct (tree t, tree fieldlist, tree attributes)
5488 bool toplevel = file_scope == current_scope;
5489 int saw_named_field;
5491 /* If this type was previously laid out as a forward reference,
5492 make sure we lay it out again. */
5496 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5500 for (x = fieldlist; x; x = TREE_CHAIN (x))
5501 if (DECL_NAME (x) != 0)
5506 if (TREE_CODE (t) == UNION_TYPE)
5509 pedwarn ("union has no named members");
5511 pedwarn ("union has no members");
5516 pedwarn ("struct has no named members");
5518 pedwarn ("struct has no members");
5523 /* Install struct as DECL_CONTEXT of each field decl.
5524 Also process specified field sizes, found in the DECL_INITIAL,
5525 storing 0 there after the type has been changed to precision equal
5526 to its width, rather than the precision of the specified standard
5527 type. (Correct layout requires the original type to have been preserved
5530 saw_named_field = 0;
5531 for (x = fieldlist; x; x = TREE_CHAIN (x))
5533 if (TREE_TYPE (x) == error_mark_node)
5536 DECL_CONTEXT (x) = t;
5538 if (TYPE_PACKED (t) && TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
5539 DECL_PACKED (x) = 1;
5541 /* If any field is const, the structure type is pseudo-const. */
5542 if (TREE_READONLY (x))
5543 C_TYPE_FIELDS_READONLY (t) = 1;
5546 /* A field that is pseudo-const makes the structure likewise. */
5547 tree t1 = TREE_TYPE (x);
5548 while (TREE_CODE (t1) == ARRAY_TYPE)
5549 t1 = TREE_TYPE (t1);
5550 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5551 && C_TYPE_FIELDS_READONLY (t1))
5552 C_TYPE_FIELDS_READONLY (t) = 1;
5555 /* Any field that is volatile means variables of this type must be
5556 treated in some ways as volatile. */
5557 if (TREE_THIS_VOLATILE (x))
5558 C_TYPE_FIELDS_VOLATILE (t) = 1;
5560 /* Any field of nominal variable size implies structure is too. */
5561 if (C_DECL_VARIABLE_SIZE (x))
5562 C_TYPE_VARIABLE_SIZE (t) = 1;
5564 if (DECL_INITIAL (x))
5566 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5567 DECL_SIZE (x) = bitsize_int (width);
5568 DECL_BIT_FIELD (x) = 1;
5569 SET_DECL_C_BIT_FIELD (x);
5572 /* Detect flexible array member in an invalid context. */
5573 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5574 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5575 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5576 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5578 if (TREE_CODE (t) == UNION_TYPE)
5580 error ("%Jflexible array member in union", x);
5581 TREE_TYPE (x) = error_mark_node;
5583 else if (TREE_CHAIN (x) != NULL_TREE)
5585 error ("%Jflexible array member not at end of struct", x);
5586 TREE_TYPE (x) = error_mark_node;
5588 else if (!saw_named_field)
5590 error ("%Jflexible array member in otherwise empty struct", x);
5591 TREE_TYPE (x) = error_mark_node;
5595 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5596 && flexible_array_type_p (TREE_TYPE (x)))
5597 pedwarn ("%Jinvalid use of structure with flexible array member", x);
5600 saw_named_field = 1;
5603 detect_field_duplicates (fieldlist);
5605 /* Now we have the nearly final fieldlist. Record it,
5606 then lay out the structure or union (including the fields). */
5608 TYPE_FIELDS (t) = fieldlist;
5612 /* Give bit-fields their proper types. */
5614 tree *fieldlistp = &fieldlist;
5616 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp)
5617 && TREE_TYPE (*fieldlistp) != error_mark_node)
5619 unsigned HOST_WIDE_INT width
5620 = tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
5621 tree type = TREE_TYPE (*fieldlistp);
5622 if (width != TYPE_PRECISION (type))
5624 TREE_TYPE (*fieldlistp)
5625 = c_build_bitfield_integer_type (width, TYPE_UNSIGNED (type));
5626 DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
5628 DECL_INITIAL (*fieldlistp) = 0;
5631 fieldlistp = &TREE_CHAIN (*fieldlistp);
5634 /* Now we have the truly final field list.
5635 Store it in this type and in the variants. */
5637 TYPE_FIELDS (t) = fieldlist;
5639 /* If there are lots of fields, sort so we can look through them fast.
5640 We arbitrarily consider 16 or more elts to be "a lot". */
5645 for (x = fieldlist; x; x = TREE_CHAIN (x))
5647 if (len > 15 || DECL_NAME (x) == NULL)
5655 struct lang_type *space;
5656 struct sorted_fields_type *space2;
5658 len += list_length (x);
5660 /* Use the same allocation policy here that make_node uses, to
5661 ensure that this lives as long as the rest of the struct decl.
5662 All decls in an inline function need to be saved. */
5664 space = GGC_CNEW (struct lang_type);
5665 space2 = GGC_NEWVAR (struct sorted_fields_type,
5666 sizeof (struct sorted_fields_type) + len * sizeof (tree));
5670 field_array = &space2->elts[0];
5671 for (x = fieldlist; x; x = TREE_CHAIN (x))
5673 field_array[len++] = x;
5675 /* If there is anonymous struct or union, break out of the loop. */
5676 if (DECL_NAME (x) == NULL)
5679 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5682 TYPE_LANG_SPECIFIC (t) = space;
5683 TYPE_LANG_SPECIFIC (t)->s->len = len;
5684 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5685 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5690 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5692 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5693 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5694 C_TYPE_FIELDS_READONLY (x) = C_TYPE_FIELDS_READONLY (t);
5695 C_TYPE_FIELDS_VOLATILE (x) = C_TYPE_FIELDS_VOLATILE (t);
5696 C_TYPE_VARIABLE_SIZE (x) = C_TYPE_VARIABLE_SIZE (t);
5699 /* If this was supposed to be a transparent union, but we can't
5700 make it one, warn and turn off the flag. */
5701 if (TREE_CODE (t) == UNION_TYPE
5702 && TYPE_TRANSPARENT_UNION (t)
5703 && (!TYPE_FIELDS (t) || TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t))))
5705 TYPE_TRANSPARENT_UNION (t) = 0;
5706 warning (0, "union cannot be made transparent");
5709 /* If this structure or union completes the type of any previous
5710 variable declaration, lay it out and output its rtl. */
5711 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5715 tree decl = TREE_VALUE (x);
5716 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5717 layout_array_type (TREE_TYPE (decl));
5718 if (TREE_CODE (decl) != TYPE_DECL)
5720 layout_decl (decl, 0);
5721 if (c_dialect_objc ())
5722 objc_check_decl (decl);
5723 rest_of_decl_compilation (decl, toplevel, 0);
5728 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5730 /* Finish debugging output for this type. */
5731 rest_of_type_compilation (t, toplevel);
5733 /* If we're inside a function proper, i.e. not file-scope and not still
5734 parsing parameters, then arrange for the size of a variable sized type
5736 if (cur_stmt_list && variably_modified_type_p (t, NULL_TREE))
5737 add_stmt (build_stmt (DECL_EXPR, build_decl (TYPE_DECL, NULL, t)));
5742 /* Lay out the type T, and its element type, and so on. */
5745 layout_array_type (tree t)
5747 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5748 layout_array_type (TREE_TYPE (t));
5752 /* Begin compiling the definition of an enumeration type.
5753 NAME is its name (or null if anonymous).
5754 Returns the type object, as yet incomplete.
5755 Also records info about it so that build_enumerator
5756 may be used to declare the individual values as they are read. */
5759 start_enum (tree name)
5763 /* If this is the real definition for a previous forward reference,
5764 fill in the contents in the same object that used to be the
5765 forward reference. */
5768 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5770 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5772 enumtype = make_node (ENUMERAL_TYPE);
5773 pushtag (name, enumtype);
5776 if (C_TYPE_BEING_DEFINED (enumtype))
5777 error ("nested redefinition of %<enum %E%>", name);
5779 C_TYPE_BEING_DEFINED (enumtype) = 1;
5781 if (TYPE_VALUES (enumtype) != 0)
5783 /* This enum is a named one that has been declared already. */
5784 error ("redeclaration of %<enum %E%>", name);
5786 /* Completely replace its old definition.
5787 The old enumerators remain defined, however. */
5788 TYPE_VALUES (enumtype) = 0;
5791 enum_next_value = integer_zero_node;
5794 if (flag_short_enums)
5795 TYPE_PACKED (enumtype) = 1;
5800 /* After processing and defining all the values of an enumeration type,
5801 install their decls in the enumeration type and finish it off.
5802 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5803 and ATTRIBUTES are the specified attributes.
5804 Returns ENUMTYPE. */
5807 finish_enum (tree enumtype, tree values, tree attributes)
5810 tree minnode = 0, maxnode = 0;
5811 int precision, unsign;
5812 bool toplevel = (file_scope == current_scope);
5813 struct lang_type *lt;
5815 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5817 /* Calculate the maximum value of any enumerator in this type. */
5819 if (values == error_mark_node)
5820 minnode = maxnode = integer_zero_node;
5823 minnode = maxnode = TREE_VALUE (values);
5824 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5826 tree value = TREE_VALUE (pair);
5827 if (tree_int_cst_lt (maxnode, value))
5829 if (tree_int_cst_lt (value, minnode))
5834 /* Construct the final type of this enumeration. It is the same
5835 as one of the integral types - the narrowest one that fits, except
5836 that normally we only go as narrow as int - and signed iff any of
5837 the values are negative. */
5838 unsign = (tree_int_cst_sgn (minnode) >= 0);
5839 precision = MAX (min_precision (minnode, unsign),
5840 min_precision (maxnode, unsign));
5842 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5844 tem = c_common_type_for_size (precision, unsign);
5847 warning (0, "enumeration values exceed range of largest integer");
5848 tem = long_long_integer_type_node;
5852 tem = unsign ? unsigned_type_node : integer_type_node;
5854 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5855 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5856 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5857 TYPE_SIZE (enumtype) = 0;
5859 /* If the precision of the type was specific with an attribute and it
5860 was too small, give an error. Otherwise, use it. */
5861 if (TYPE_PRECISION (enumtype))
5863 if (precision > TYPE_PRECISION (enumtype))
5864 error ("specified mode too small for enumeral values");
5867 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5869 layout_type (enumtype);
5871 if (values != error_mark_node)
5873 /* Change the type of the enumerators to be the enum type. We
5874 need to do this irrespective of the size of the enum, for
5875 proper type checking. Replace the DECL_INITIALs of the
5876 enumerators, and the value slots of the list, with copies
5877 that have the enum type; they cannot be modified in place
5878 because they may be shared (e.g. integer_zero_node) Finally,
5879 change the purpose slots to point to the names of the decls. */
5880 for (pair = values; pair; pair = TREE_CHAIN (pair))
5882 tree enu = TREE_PURPOSE (pair);
5883 tree ini = DECL_INITIAL (enu);
5885 TREE_TYPE (enu) = enumtype;
5887 /* The ISO C Standard mandates enumerators to have type int,
5888 even though the underlying type of an enum type is
5889 unspecified. Here we convert any enumerators that fit in
5890 an int to type int, to avoid promotions to unsigned types
5891 when comparing integers with enumerators that fit in the
5892 int range. When -pedantic is given, build_enumerator()
5893 would have already taken care of those that don't fit. */
5894 if (int_fits_type_p (ini, integer_type_node))
5895 tem = integer_type_node;
5898 ini = convert (tem, ini);
5900 DECL_INITIAL (enu) = ini;
5901 TREE_PURPOSE (pair) = DECL_NAME (enu);
5902 TREE_VALUE (pair) = ini;
5905 TYPE_VALUES (enumtype) = values;
5908 /* Record the min/max values so that we can warn about bit-field
5909 enumerations that are too small for the values. */
5910 lt = GGC_CNEW (struct lang_type);
5911 lt->enum_min = minnode;
5912 lt->enum_max = maxnode;
5913 TYPE_LANG_SPECIFIC (enumtype) = lt;
5915 /* Fix up all variant types of this enum type. */
5916 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5918 if (tem == enumtype)
5920 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5921 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5922 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5923 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5924 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5925 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5926 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5927 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5928 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5929 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5930 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5933 /* Finish debugging output for this type. */
5934 rest_of_type_compilation (enumtype, toplevel);
5939 /* Build and install a CONST_DECL for one value of the
5940 current enumeration type (one that was begun with start_enum).
5941 Return a tree-list containing the CONST_DECL and its value.
5942 Assignment of sequential values by default is handled here. */
5945 build_enumerator (tree name, tree value)
5949 /* Validate and default VALUE. */
5953 /* Don't issue more errors for error_mark_node (i.e. an
5954 undeclared identifier) - just ignore the value expression. */
5955 if (value == error_mark_node)
5957 else if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
5958 || TREE_CODE (value) != INTEGER_CST)
5960 error ("enumerator value for %qE is not an integer constant", name);
5965 value = default_conversion (value);
5966 constant_expression_warning (value);
5970 /* Default based on previous value. */
5971 /* It should no longer be possible to have NON_LVALUE_EXPR
5975 value = enum_next_value;
5977 error ("overflow in enumeration values");
5980 if (pedantic && !int_fits_type_p (value, integer_type_node))
5982 pedwarn ("ISO C restricts enumerator values to range of %<int%>");
5983 /* XXX This causes -pedantic to change the meaning of the program.
5984 Remove? -zw 2004-03-15 */
5985 value = convert (integer_type_node, value);
5988 /* Set basis for default for next value. */
5989 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
5990 enum_overflow = tree_int_cst_lt (enum_next_value, value);
5992 /* Now create a declaration for the enum value name. */
5994 type = TREE_TYPE (value);
5995 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
5996 TYPE_PRECISION (integer_type_node)),
5997 (TYPE_PRECISION (type)
5998 >= TYPE_PRECISION (integer_type_node)
5999 && TYPE_UNSIGNED (type)));
6001 decl = build_decl (CONST_DECL, name, type);
6002 DECL_INITIAL (decl) = convert (type, value);
6005 return tree_cons (decl, value, NULL_TREE);
6009 /* Create the FUNCTION_DECL for a function definition.
6010 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
6011 the declaration; they describe the function's name and the type it returns,
6012 but twisted together in a fashion that parallels the syntax of C.
6014 This function creates a binding context for the function body
6015 as well as setting up the FUNCTION_DECL in current_function_decl.
6017 Returns 1 on success. If the DECLARATOR is not suitable for a function
6018 (it defines a datum instead), we return 0, which tells
6019 yyparse to report a parse error. */
6022 start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
6025 tree decl1, old_decl;
6026 tree restype, resdecl;
6027 struct c_label_context_se *nstack_se;
6028 struct c_label_context_vm *nstack_vm;
6030 current_function_returns_value = 0; /* Assume, until we see it does. */
6031 current_function_returns_null = 0;
6032 current_function_returns_abnormally = 0;
6033 warn_about_return_type = 0;
6034 c_switch_stack = NULL;
6036 nstack_se = XOBNEW (&parser_obstack, struct c_label_context_se);
6037 nstack_se->labels_def = NULL;
6038 nstack_se->labels_used = NULL;
6039 nstack_se->next = label_context_stack_se;
6040 label_context_stack_se = nstack_se;
6042 nstack_vm = XOBNEW (&parser_obstack, struct c_label_context_vm);
6043 nstack_vm->labels_def = NULL;
6044 nstack_vm->labels_used = NULL;
6045 nstack_vm->scope = 0;
6046 nstack_vm->next = label_context_stack_vm;
6047 label_context_stack_vm = nstack_vm;
6049 /* Indicate no valid break/continue context by setting these variables
6050 to some non-null, non-label value. We'll notice and emit the proper
6051 error message in c_finish_bc_stmt. */
6052 c_break_label = c_cont_label = size_zero_node;
6054 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, true, NULL);
6056 /* If the declarator is not suitable for a function definition,
6057 cause a syntax error. */
6060 label_context_stack_se = label_context_stack_se->next;
6061 label_context_stack_vm = label_context_stack_vm->next;
6065 decl_attributes (&decl1, attributes, 0);
6067 if (DECL_DECLARED_INLINE_P (decl1)
6068 && DECL_UNINLINABLE (decl1)
6069 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6070 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
6073 /* Handle gnu_inline attribute. */
6074 if (declspecs->inline_p
6075 && !flag_gnu89_inline
6076 && TREE_CODE (decl1) == FUNCTION_DECL
6077 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl1)))
6079 if (declspecs->storage_class != csc_static)
6080 DECL_EXTERNAL (decl1) = !DECL_EXTERNAL (decl1);
6083 announce_function (decl1);
6085 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6087 error ("return type is an incomplete type");
6088 /* Make it return void instead. */
6090 = build_function_type (void_type_node,
6091 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6094 if (warn_about_return_type)
6095 pedwarn_c99 ("return type defaults to %<int%>");
6097 /* Make the init_value nonzero so pushdecl knows this is not tentative.
6098 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
6099 DECL_INITIAL (decl1) = error_mark_node;
6101 /* If this definition isn't a prototype and we had a prototype declaration
6102 before, copy the arg type info from that prototype. */
6103 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
6104 if (old_decl && TREE_CODE (old_decl) != FUNCTION_DECL)
6106 current_function_prototype_locus = UNKNOWN_LOCATION;
6107 current_function_prototype_built_in = false;
6108 current_function_prototype_arg_types = NULL_TREE;
6109 if (TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6111 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6112 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6113 TREE_TYPE (TREE_TYPE (old_decl))))
6115 TREE_TYPE (decl1) = composite_type (TREE_TYPE (old_decl),
6117 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
6118 current_function_prototype_built_in
6119 = C_DECL_BUILTIN_PROTOTYPE (old_decl);
6120 current_function_prototype_arg_types
6121 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
6123 if (TREE_PUBLIC (decl1))
6125 /* If there is an external prototype declaration of this
6126 function, record its location but do not copy information
6127 to this decl. This may be an invisible declaration
6128 (built-in or in a scope which has finished) or simply
6129 have more refined argument types than any declaration
6131 struct c_binding *b;
6132 for (b = I_SYMBOL_BINDING (DECL_NAME (decl1)); b; b = b->shadowed)
6133 if (B_IN_SCOPE (b, external_scope))
6137 tree ext_decl, ext_type;
6139 ext_type = b->type ? b->type : TREE_TYPE (ext_decl);
6140 if (TREE_CODE (ext_type) == FUNCTION_TYPE
6141 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6142 TREE_TYPE (ext_type)))
6144 current_function_prototype_locus
6145 = DECL_SOURCE_LOCATION (ext_decl);
6146 current_function_prototype_built_in
6147 = C_DECL_BUILTIN_PROTOTYPE (ext_decl);
6148 current_function_prototype_arg_types
6149 = TYPE_ARG_TYPES (ext_type);
6155 /* Optionally warn of old-fashioned def with no previous prototype. */
6156 if (warn_strict_prototypes
6157 && old_decl != error_mark_node
6158 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6159 && C_DECL_ISNT_PROTOTYPE (old_decl))
6160 warning (OPT_Wstrict_prototypes,
6161 "function declaration isn%'t a prototype");
6162 /* Optionally warn of any global def with no previous prototype. */
6163 else if (warn_missing_prototypes
6164 && old_decl != error_mark_node
6165 && TREE_PUBLIC (decl1)
6166 && !MAIN_NAME_P (DECL_NAME (decl1))
6167 && C_DECL_ISNT_PROTOTYPE (old_decl))
6168 warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl1);
6169 /* Optionally warn of any def with no previous prototype
6170 if the function has already been used. */
6171 else if (warn_missing_prototypes
6173 && old_decl != error_mark_node
6174 && TREE_USED (old_decl)
6175 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6176 warning (OPT_Wmissing_prototypes,
6177 "%q+D was used with no prototype before its definition", decl1);
6178 /* Optionally warn of any global def with no previous declaration. */
6179 else if (warn_missing_declarations
6180 && TREE_PUBLIC (decl1)
6182 && !MAIN_NAME_P (DECL_NAME (decl1)))
6183 warning (OPT_Wmissing_declarations, "no previous declaration for %q+D",
6185 /* Optionally warn of any def with no previous declaration
6186 if the function has already been used. */
6187 else if (warn_missing_declarations
6189 && old_decl != error_mark_node
6190 && TREE_USED (old_decl)
6191 && C_DECL_IMPLICIT (old_decl))
6192 warning (OPT_Wmissing_declarations,
6193 "%q+D was used with no declaration before its definition", decl1);
6195 /* This function exists in static storage.
6196 (This does not mean `static' in the C sense!) */
6197 TREE_STATIC (decl1) = 1;
6199 /* A nested function is not global. */
6200 if (current_function_decl != 0)
6201 TREE_PUBLIC (decl1) = 0;
6203 /* This is the earliest point at which we might know the assembler
6204 name of the function. Thus, if it's set before this, die horribly. */
6205 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl1));
6207 /* If #pragma weak was used, mark the decl weak now. */
6208 if (current_scope == file_scope)
6209 maybe_apply_pragma_weak (decl1);
6211 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6212 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6214 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6215 != integer_type_node)
6216 pedwarn ("return type of %q+D is not %<int%>", decl1);
6218 check_main_parameter_types(decl1);
6220 if (!TREE_PUBLIC (decl1))
6221 pedwarn ("%q+D is normally a non-static function", decl1);
6224 /* Record the decl so that the function name is defined.
6225 If we already have a decl for this name, and it is a FUNCTION_DECL,
6226 use the old decl. */
6228 current_function_decl = pushdecl (decl1);
6231 declare_parm_level ();
6233 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6234 /* Promote the value to int before returning it. */
6235 if (c_promoting_integer_type_p (restype))
6237 /* It retains unsignedness if not really getting wider. */
6238 if (TYPE_UNSIGNED (restype)
6239 && (TYPE_PRECISION (restype)
6240 == TYPE_PRECISION (integer_type_node)))
6241 restype = unsigned_type_node;
6243 restype = integer_type_node;
6246 resdecl = build_decl (RESULT_DECL, NULL_TREE, restype);
6247 DECL_ARTIFICIAL (resdecl) = 1;
6248 DECL_IGNORED_P (resdecl) = 1;
6249 DECL_RESULT (current_function_decl) = resdecl;
6251 start_fname_decls ();
6256 /* Subroutine of store_parm_decls which handles new-style function
6257 definitions (prototype format). The parms already have decls, so we
6258 need only record them as in effect and complain if any redundant
6259 old-style parm decls were written. */
6261 store_parm_decls_newstyle (tree fndecl, const struct c_arg_info *arg_info)
6265 if (current_scope->bindings)
6267 error ("%Jold-style parameter declarations in prototyped "
6268 "function definition", fndecl);
6270 /* Get rid of the old-style declarations. */
6274 /* Don't issue this warning for nested functions, and don't issue this
6275 warning if we got here because ARG_INFO_TYPES was error_mark_node
6276 (this happens when a function definition has just an ellipsis in
6277 its parameter list). */
6278 else if (!in_system_header && !current_function_scope
6279 && arg_info->types != error_mark_node)
6280 warning (OPT_Wtraditional,
6281 "%Jtraditional C rejects ISO C style function definitions",
6284 /* Now make all the parameter declarations visible in the function body.
6285 We can bypass most of the grunt work of pushdecl. */
6286 for (decl = arg_info->parms; decl; decl = TREE_CHAIN (decl))
6288 DECL_CONTEXT (decl) = current_function_decl;
6289 if (DECL_NAME (decl))
6291 bind (DECL_NAME (decl), decl, current_scope,
6292 /*invisible=*/false, /*nested=*/false);
6293 if (!TREE_USED (decl))
6294 warn_if_shadowing (decl);
6297 error ("%Jparameter name omitted", decl);
6300 /* Record the parameter list in the function declaration. */
6301 DECL_ARGUMENTS (fndecl) = arg_info->parms;
6303 /* Now make all the ancillary declarations visible, likewise. */
6304 for (decl = arg_info->others; decl; decl = TREE_CHAIN (decl))
6306 DECL_CONTEXT (decl) = current_function_decl;
6307 if (DECL_NAME (decl))
6308 bind (DECL_NAME (decl), decl, current_scope,
6309 /*invisible=*/false, /*nested=*/false);
6312 /* And all the tag declarations. */
6313 for (decl = arg_info->tags; decl; decl = TREE_CHAIN (decl))
6314 if (TREE_PURPOSE (decl))
6315 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
6316 /*invisible=*/false, /*nested=*/false);
6319 /* Subroutine of store_parm_decls which handles old-style function
6320 definitions (separate parameter list and declarations). */
6323 store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
6325 struct c_binding *b;
6326 tree parm, decl, last;
6327 tree parmids = arg_info->parms;
6328 struct pointer_set_t *seen_args = pointer_set_create ();
6330 if (!in_system_header)
6331 warning (OPT_Wold_style_definition, "%Jold-style function definition",
6334 /* Match each formal parameter name with its declaration. Save each
6335 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
6336 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6338 if (TREE_VALUE (parm) == 0)
6340 error ("%Jparameter name missing from parameter list", fndecl);
6341 TREE_PURPOSE (parm) = 0;
6345 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
6346 if (b && B_IN_CURRENT_SCOPE (b))
6349 /* If we got something other than a PARM_DECL it is an error. */
6350 if (TREE_CODE (decl) != PARM_DECL)
6351 error ("%q+D declared as a non-parameter", decl);
6352 /* If the declaration is already marked, we have a duplicate
6353 name. Complain and ignore the duplicate. */
6354 else if (pointer_set_contains (seen_args, decl))
6356 error ("multiple parameters named %q+D", decl);
6357 TREE_PURPOSE (parm) = 0;
6360 /* If the declaration says "void", complain and turn it into
6362 else if (VOID_TYPE_P (TREE_TYPE (decl)))
6364 error ("parameter %q+D declared with void type", decl);
6365 TREE_TYPE (decl) = integer_type_node;
6366 DECL_ARG_TYPE (decl) = integer_type_node;
6367 layout_decl (decl, 0);
6369 warn_if_shadowing (decl);
6371 /* If no declaration found, default to int. */
6374 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
6375 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
6376 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
6378 warn_if_shadowing (decl);
6381 pedwarn ("type of %q+D defaults to %<int%>", decl);
6383 warning (OPT_Wmissing_parameter_type, "type of %q+D defaults to %<int%>", decl);
6386 TREE_PURPOSE (parm) = decl;
6387 pointer_set_insert (seen_args, decl);
6390 /* Now examine the parms chain for incomplete declarations
6391 and declarations with no corresponding names. */
6393 for (b = current_scope->bindings; b; b = b->prev)
6396 if (TREE_CODE (parm) != PARM_DECL)
6399 if (TREE_TYPE (parm) != error_mark_node
6400 && !COMPLETE_TYPE_P (TREE_TYPE (parm)))
6402 error ("parameter %q+D has incomplete type", parm);
6403 TREE_TYPE (parm) = error_mark_node;
6406 if (!pointer_set_contains (seen_args, parm))
6408 error ("declaration for parameter %q+D but no such parameter", parm);
6410 /* Pretend the parameter was not missing.
6411 This gets us to a standard state and minimizes
6412 further error messages. */
6413 parmids = chainon (parmids, tree_cons (parm, 0, 0));
6417 /* Chain the declarations together in the order of the list of
6418 names. Store that chain in the function decl, replacing the
6419 list of names. Update the current scope to match. */
6420 DECL_ARGUMENTS (fndecl) = 0;
6422 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6423 if (TREE_PURPOSE (parm))
6425 if (parm && TREE_PURPOSE (parm))
6427 last = TREE_PURPOSE (parm);
6428 DECL_ARGUMENTS (fndecl) = last;
6430 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
6431 if (TREE_PURPOSE (parm))
6433 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6434 last = TREE_PURPOSE (parm);
6436 TREE_CHAIN (last) = 0;
6439 pointer_set_destroy (seen_args);
6441 /* If there was a previous prototype,
6442 set the DECL_ARG_TYPE of each argument according to
6443 the type previously specified, and report any mismatches. */
6445 if (current_function_prototype_arg_types)
6448 for (parm = DECL_ARGUMENTS (fndecl),
6449 type = current_function_prototype_arg_types;
6450 parm || (type && TREE_VALUE (type) != error_mark_node
6451 && (TYPE_MAIN_VARIANT (TREE_VALUE (type)) != void_type_node));
6452 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6454 if (parm == 0 || type == 0
6455 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6457 if (current_function_prototype_built_in)
6458 warning (0, "number of arguments doesn%'t match "
6459 "built-in prototype");
6462 error ("number of arguments doesn%'t match prototype");
6463 error ("%Hprototype declaration",
6464 ¤t_function_prototype_locus);
6468 /* Type for passing arg must be consistent with that
6469 declared for the arg. ISO C says we take the unqualified
6470 type for parameters declared with qualified type. */
6471 if (!comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6472 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6474 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6475 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6477 /* Adjust argument to match prototype. E.g. a previous
6478 `int foo(float);' prototype causes
6479 `int foo(x) float x; {...}' to be treated like
6480 `int foo(float x) {...}'. This is particularly
6481 useful for argument types like uid_t. */
6482 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6484 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6485 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6486 && TYPE_PRECISION (TREE_TYPE (parm))
6487 < TYPE_PRECISION (integer_type_node))
6488 DECL_ARG_TYPE (parm) = integer_type_node;
6492 /* ??? Is it possible to get here with a
6493 built-in prototype or will it always have
6494 been diagnosed as conflicting with an
6495 old-style definition and discarded? */
6496 if (current_function_prototype_built_in)
6497 warning (0, "promoted argument %qD "
6498 "doesn%'t match built-in prototype", parm);
6501 pedwarn ("promoted argument %qD "
6502 "doesn%'t match prototype", parm);
6503 pedwarn ("%Hprototype declaration",
6504 ¤t_function_prototype_locus);
6510 if (current_function_prototype_built_in)
6511 warning (0, "argument %qD doesn%'t match "
6512 "built-in prototype", parm);
6515 error ("argument %qD doesn%'t match prototype", parm);
6516 error ("%Hprototype declaration",
6517 ¤t_function_prototype_locus);
6522 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6525 /* Otherwise, create a prototype that would match. */
6529 tree actual = 0, last = 0, type;
6531 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6533 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6535 TREE_CHAIN (last) = type;
6540 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6542 TREE_CHAIN (last) = type;
6546 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6547 of the type of this function, but we need to avoid having this
6548 affect the types of other similarly-typed functions, so we must
6549 first force the generation of an identical (but separate) type
6550 node for the relevant function type. The new node we create
6551 will be a variant of the main variant of the original function
6554 TREE_TYPE (fndecl) = build_variant_type_copy (TREE_TYPE (fndecl));
6556 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6560 /* Store parameter declarations passed in ARG_INFO into the current
6561 function declaration. */
6564 store_parm_decls_from (struct c_arg_info *arg_info)
6566 current_function_arg_info = arg_info;
6567 store_parm_decls ();
6570 /* Store the parameter declarations into the current function declaration.
6571 This is called after parsing the parameter declarations, before
6572 digesting the body of the function.
6574 For an old-style definition, construct a prototype out of the old-style
6575 parameter declarations and inject it into the function's type. */
6578 store_parm_decls (void)
6580 tree fndecl = current_function_decl;
6583 /* The argument information block for FNDECL. */
6584 struct c_arg_info *arg_info = current_function_arg_info;
6585 current_function_arg_info = 0;
6587 /* True if this definition is written with a prototype. Note:
6588 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6589 list in a function definition as equivalent to (void) -- an
6590 empty argument list specifies the function has no parameters,
6591 but only (void) sets up a prototype for future calls. */
6592 proto = arg_info->types != 0;
6595 store_parm_decls_newstyle (fndecl, arg_info);
6597 store_parm_decls_oldstyle (fndecl, arg_info);
6599 /* The next call to push_scope will be a function body. */
6601 next_is_function_body = true;
6603 /* Write a record describing this function definition to the prototypes
6604 file (if requested). */
6606 gen_aux_info_record (fndecl, 1, 0, proto);
6608 /* Initialize the RTL code for the function. */
6609 allocate_struct_function (fndecl);
6611 /* Begin the statement tree for this function. */
6612 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6614 /* ??? Insert the contents of the pending sizes list into the function
6615 to be evaluated. The only reason left to have this is
6616 void foo(int n, int array[n++])
6617 because we throw away the array type in favor of a pointer type, and
6618 thus won't naturally see the SAVE_EXPR containing the increment. All
6619 other pending sizes would be handled by gimplify_parameters. */
6622 for (t = nreverse (get_pending_sizes ()); t ; t = TREE_CHAIN (t))
6623 add_stmt (TREE_VALUE (t));
6626 /* Even though we're inside a function body, we still don't want to
6627 call expand_expr to calculate the size of a variable-sized array.
6628 We haven't necessarily assigned RTL to all variables yet, so it's
6629 not safe to try to expand expressions involving them. */
6630 cfun->x_dont_save_pending_sizes_p = 1;
6633 /* Emit diagnostics that require gimple input for detection. Operate on
6634 FNDECL and all its nested functions. */
6637 c_gimple_diagnostics_recursively (tree fndecl)
6639 struct cgraph_node *cgn;
6641 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6642 c_warn_unused_result (&DECL_SAVED_TREE (fndecl));
6644 /* Notice when OpenMP structured block constraints are violated. */
6646 diagnose_omp_structured_block_errors (fndecl);
6648 /* Finalize all nested functions now. */
6649 cgn = cgraph_node (fndecl);
6650 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6651 c_gimple_diagnostics_recursively (cgn->decl);
6654 /* Finish up a function declaration and compile that function
6655 all the way to assembler language output. The free the storage
6656 for the function definition.
6658 This is called after parsing the body of the function definition. */
6661 finish_function (void)
6663 tree fndecl = current_function_decl;
6665 label_context_stack_se = label_context_stack_se->next;
6666 label_context_stack_vm = label_context_stack_vm->next;
6668 if (TREE_CODE (fndecl) == FUNCTION_DECL
6669 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6671 tree args = DECL_ARGUMENTS (fndecl);
6672 for (; args; args = TREE_CHAIN (args))
6674 tree type = TREE_TYPE (args);
6675 if (INTEGRAL_TYPE_P (type)
6676 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6677 DECL_ARG_TYPE (args) = integer_type_node;
6681 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6682 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6684 /* Must mark the RESULT_DECL as being in this function. */
6686 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6687 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6689 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6691 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6692 != integer_type_node)
6694 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6695 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6697 pedwarn ("return type of %q+D is not %<int%>", fndecl);
6703 tree stmt = c_finish_return (integer_zero_node);
6704 #ifdef USE_MAPPED_LOCATION
6705 /* Hack. We don't want the middle-end to warn that this return
6706 is unreachable, so we mark its location as special. Using
6707 UNKNOWN_LOCATION has the problem that it gets clobbered in
6708 annotate_one_with_locus. A cleaner solution might be to
6709 ensure ! should_carry_locus_p (stmt), but that needs a flag.
6711 SET_EXPR_LOCATION (stmt, BUILTINS_LOCATION);
6713 /* Hack. We don't want the middle-end to warn that this
6714 return is unreachable, so put the statement on the
6716 annotate_with_file_line (stmt, input_filename, 0);
6722 /* Tie off the statement tree for this function. */
6723 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6725 finish_fname_decls ();
6727 /* Complain if there's just no return statement. */
6728 if (warn_return_type
6729 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6730 && !current_function_returns_value && !current_function_returns_null
6731 /* Don't complain if we are no-return. */
6732 && !current_function_returns_abnormally
6733 /* Don't warn for main(). */
6734 && !MAIN_NAME_P (DECL_NAME (fndecl))
6735 /* Or if they didn't actually specify a return type. */
6736 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6737 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6738 inline function, as we might never be compiled separately. */
6739 && DECL_INLINE (fndecl))
6741 warning (OPT_Wreturn_type,
6742 "no return statement in function returning non-void");
6743 TREE_NO_WARNING (fndecl) = 1;
6746 /* With just -Wextra, complain only if function returns both with
6747 and without a value. */
6749 && current_function_returns_value
6750 && current_function_returns_null)
6751 warning (OPT_Wextra, "this function may return with or without a value");
6753 /* Store the end of the function, so that we get good line number
6754 info for the epilogue. */
6755 cfun->function_end_locus = input_location;
6757 /* Keep track of functions declared with the "constructor" and
6758 "destructor" attribute. */
6759 c_record_cdtor_fn (fndecl);
6761 /* Finalize the ELF visibility for the function. */
6762 c_determine_visibility (fndecl);
6764 /* Genericize before inlining. Delay genericizing nested functions
6765 until their parent function is genericized. Since finalizing
6766 requires GENERIC, delay that as well. */
6768 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node
6769 && !undef_nested_function)
6771 if (!decl_function_context (fndecl))
6773 c_genericize (fndecl);
6774 c_gimple_diagnostics_recursively (fndecl);
6776 /* ??? Objc emits functions after finalizing the compilation unit.
6777 This should be cleaned up later and this conditional removed. */
6778 if (cgraph_global_info_ready)
6780 c_expand_body (fndecl);
6784 cgraph_finalize_function (fndecl, false);
6788 /* Register this function with cgraph just far enough to get it
6789 added to our parent's nested function list. Handy, since the
6790 C front end doesn't have such a list. */
6791 (void) cgraph_node (fndecl);
6795 if (!decl_function_context (fndecl))
6796 undef_nested_function = false;
6798 /* We're leaving the context of this function, so zap cfun.
6799 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6800 tree_rest_of_compilation. */
6802 current_function_decl = NULL;
6805 /* Check the declarations given in a for-loop for satisfying the C99
6806 constraints. If exactly one such decl is found, return it. */
6809 check_for_loop_decls (void)
6811 struct c_binding *b;
6812 tree one_decl = NULL_TREE;
6818 /* If we get here, declarations have been used in a for loop without
6819 the C99 for loop scope. This doesn't make much sense, so don't
6821 error ("%<for%> loop initial declaration used outside C99 mode");
6824 /* C99 subclause 6.8.5 paragraph 3:
6826 [#3] The declaration part of a for statement shall only
6827 declare identifiers for objects having storage class auto or
6830 It isn't clear whether, in this sentence, "identifiers" binds to
6831 "shall only declare" or to "objects" - that is, whether all identifiers
6832 declared must be identifiers for objects, or whether the restriction
6833 only applies to those that are. (A question on this in comp.std.c
6834 in November 2000 received no answer.) We implement the strictest
6835 interpretation, to avoid creating an extension which later causes
6838 for (b = current_scope->bindings; b; b = b->prev)
6841 tree decl = b->decl;
6846 switch (TREE_CODE (decl))
6849 if (TREE_STATIC (decl))
6850 error ("declaration of static variable %q+D in %<for%> loop "
6851 "initial declaration", decl);
6852 else if (DECL_EXTERNAL (decl))
6853 error ("declaration of %<extern%> variable %q+D in %<for%> loop "
6854 "initial declaration", decl);
6858 error ("%<struct %E%> declared in %<for%> loop initial declaration",
6862 error ("%<union %E%> declared in %<for%> loop initial declaration",
6866 error ("%<enum %E%> declared in %<for%> loop initial declaration",
6870 error ("declaration of non-variable %q+D in %<for%> loop "
6871 "initial declaration", decl);
6878 return n_decls == 1 ? one_decl : NULL_TREE;
6881 /* Save and reinitialize the variables
6882 used during compilation of a C function. */
6885 c_push_function_context (struct function *f)
6887 struct language_function *p;
6888 p = GGC_NEW (struct language_function);
6891 p->base.x_stmt_tree = c_stmt_tree;
6892 p->x_break_label = c_break_label;
6893 p->x_cont_label = c_cont_label;
6894 p->x_switch_stack = c_switch_stack;
6895 p->arg_info = current_function_arg_info;
6896 p->returns_value = current_function_returns_value;
6897 p->returns_null = current_function_returns_null;
6898 p->returns_abnormally = current_function_returns_abnormally;
6899 p->warn_about_return_type = warn_about_return_type;
6902 /* Restore the variables used during compilation of a C function. */
6905 c_pop_function_context (struct function *f)
6907 struct language_function *p = f->language;
6909 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6910 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6912 /* Stop pointing to the local nodes about to be freed. */
6913 /* But DECL_INITIAL must remain nonzero so we know this
6914 was an actual function definition. */
6915 DECL_INITIAL (current_function_decl) = error_mark_node;
6916 DECL_ARGUMENTS (current_function_decl) = 0;
6919 c_stmt_tree = p->base.x_stmt_tree;
6920 c_break_label = p->x_break_label;
6921 c_cont_label = p->x_cont_label;
6922 c_switch_stack = p->x_switch_stack;
6923 current_function_arg_info = p->arg_info;
6924 current_function_returns_value = p->returns_value;
6925 current_function_returns_null = p->returns_null;
6926 current_function_returns_abnormally = p->returns_abnormally;
6927 warn_about_return_type = p->warn_about_return_type;
6932 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6935 c_dup_lang_specific_decl (tree decl)
6937 struct lang_decl *ld;
6939 if (!DECL_LANG_SPECIFIC (decl))
6942 ld = GGC_NEW (struct lang_decl);
6943 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
6944 DECL_LANG_SPECIFIC (decl) = ld;
6947 /* The functions below are required for functionality of doing
6948 function at once processing in the C front end. Currently these
6949 functions are not called from anywhere in the C front end, but as
6950 these changes continue, that will change. */
6952 /* Returns the stmt_tree (if any) to which statements are currently
6953 being added. If there is no active statement-tree, NULL is
6957 current_stmt_tree (void)
6959 return &c_stmt_tree;
6962 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
6966 anon_aggr_type_p (tree ARG_UNUSED (node))
6971 /* Return the global value of T as a symbol. */
6974 identifier_global_value (tree t)
6976 struct c_binding *b;
6978 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
6979 if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
6985 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
6986 otherwise the name is found in ridpointers from RID_INDEX. */
6989 record_builtin_type (enum rid rid_index, const char *name, tree type)
6993 id = ridpointers[(int) rid_index];
6995 id = get_identifier (name);
6996 decl = build_decl (TYPE_DECL, id, type);
6998 if (debug_hooks->type_decl)
6999 debug_hooks->type_decl (decl, false);
7002 /* Build the void_list_node (void_type_node having been created). */
7004 build_void_list_node (void)
7006 tree t = build_tree_list (NULL_TREE, void_type_node);
7010 /* Return a c_parm structure with the given SPECS, ATTRS and DECLARATOR. */
7013 build_c_parm (struct c_declspecs *specs, tree attrs,
7014 struct c_declarator *declarator)
7016 struct c_parm *ret = XOBNEW (&parser_obstack, struct c_parm);
7019 ret->declarator = declarator;
7023 /* Return a declarator with nested attributes. TARGET is the inner
7024 declarator to which these attributes apply. ATTRS are the
7027 struct c_declarator *
7028 build_attrs_declarator (tree attrs, struct c_declarator *target)
7030 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7031 ret->kind = cdk_attrs;
7032 ret->declarator = target;
7033 ret->u.attrs = attrs;
7037 /* Return a declarator for a function with arguments specified by ARGS
7038 and return type specified by TARGET. */
7040 struct c_declarator *
7041 build_function_declarator (struct c_arg_info *args,
7042 struct c_declarator *target)
7044 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7045 ret->kind = cdk_function;
7046 ret->declarator = target;
7047 ret->u.arg_info = args;
7051 /* Return a declarator for the identifier IDENT (which may be
7052 NULL_TREE for an abstract declarator). */
7054 struct c_declarator *
7055 build_id_declarator (tree ident)
7057 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7059 ret->declarator = 0;
7061 /* Default value - may get reset to a more precise location. */
7062 ret->id_loc = input_location;
7066 /* Return something to represent absolute declarators containing a *.
7067 TARGET is the absolute declarator that the * contains.
7068 TYPE_QUALS_ATTRS is a structure for type qualifiers and attributes
7069 to apply to the pointer type. */
7071 struct c_declarator *
7072 make_pointer_declarator (struct c_declspecs *type_quals_attrs,
7073 struct c_declarator *target)
7077 struct c_declarator *itarget = target;
7078 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7079 if (type_quals_attrs)
7081 attrs = type_quals_attrs->attrs;
7082 quals = quals_from_declspecs (type_quals_attrs);
7083 if (attrs != NULL_TREE)
7084 itarget = build_attrs_declarator (attrs, target);
7086 ret->kind = cdk_pointer;
7087 ret->declarator = itarget;
7088 ret->u.pointer_quals = quals;
7092 /* Return a pointer to a structure for an empty list of declaration
7095 struct c_declspecs *
7096 build_null_declspecs (void)
7098 struct c_declspecs *ret = XOBNEW (&parser_obstack, struct c_declspecs);
7102 ret->typespec_word = cts_none;
7103 ret->storage_class = csc_none;
7104 ret->declspecs_seen_p = false;
7105 ret->type_seen_p = false;
7106 ret->non_sc_seen_p = false;
7107 ret->typedef_p = false;
7108 ret->tag_defined_p = false;
7109 ret->explicit_signed_p = false;
7110 ret->deprecated_p = false;
7111 ret->default_int_p = false;
7112 ret->long_p = false;
7113 ret->long_long_p = false;
7114 ret->short_p = false;
7115 ret->signed_p = false;
7116 ret->unsigned_p = false;
7117 ret->complex_p = false;
7118 ret->inline_p = false;
7119 ret->thread_p = false;
7120 ret->const_p = false;
7121 ret->volatile_p = false;
7122 ret->restrict_p = false;
7126 /* Add the type qualifier QUAL to the declaration specifiers SPECS,
7129 struct c_declspecs *
7130 declspecs_add_qual (struct c_declspecs *specs, tree qual)
7134 specs->non_sc_seen_p = true;
7135 specs->declspecs_seen_p = true;
7136 gcc_assert (TREE_CODE (qual) == IDENTIFIER_NODE
7137 && C_IS_RESERVED_WORD (qual));
7138 i = C_RID_CODE (qual);
7142 dupe = specs->const_p;
7143 specs->const_p = true;
7146 dupe = specs->volatile_p;
7147 specs->volatile_p = true;
7150 dupe = specs->restrict_p;
7151 specs->restrict_p = true;
7156 if (dupe && pedantic && !flag_isoc99)
7157 pedwarn ("duplicate %qE", qual);
7161 /* Add the type specifier TYPE to the declaration specifiers SPECS,
7164 struct c_declspecs *
7165 declspecs_add_type (struct c_declspecs *specs, struct c_typespec spec)
7167 tree type = spec.spec;
7168 specs->non_sc_seen_p = true;
7169 specs->declspecs_seen_p = true;
7170 specs->type_seen_p = true;
7171 if (TREE_DEPRECATED (type))
7172 specs->deprecated_p = true;
7174 /* Handle type specifier keywords. */
7175 if (TREE_CODE (type) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (type))
7177 enum rid i = C_RID_CODE (type);
7180 error ("two or more data types in declaration specifiers");
7183 if ((int) i <= (int) RID_LAST_MODIFIER)
7185 /* "long", "short", "signed", "unsigned" or "_Complex". */
7190 if (specs->long_long_p)
7192 error ("%<long long long%> is too long for GCC");
7197 if (specs->typespec_word == cts_double)
7199 error ("both %<long long%> and %<double%> in "
7200 "declaration specifiers");
7203 if (pedantic && !flag_isoc99 && !in_system_header
7205 pedwarn ("ISO C90 does not support %<long long%>");
7206 specs->long_long_p = 1;
7210 error ("both %<long%> and %<short%> in "
7211 "declaration specifiers");
7212 else if (specs->typespec_word == cts_void)
7213 error ("both %<long%> and %<void%> in "
7214 "declaration specifiers");
7215 else if (specs->typespec_word == cts_bool)
7216 error ("both %<long%> and %<_Bool%> in "
7217 "declaration specifiers");
7218 else if (specs->typespec_word == cts_char)
7219 error ("both %<long%> and %<char%> in "
7220 "declaration specifiers");
7221 else if (specs->typespec_word == cts_float)
7222 error ("both %<long%> and %<float%> in "
7223 "declaration specifiers");
7224 else if (specs->typespec_word == cts_dfloat32)
7225 error ("both %<long%> and %<_Decimal32%> in "
7226 "declaration specifiers");
7227 else if (specs->typespec_word == cts_dfloat64)
7228 error ("both %<long%> and %<_Decimal64%> in "
7229 "declaration specifiers");
7230 else if (specs->typespec_word == cts_dfloat128)
7231 error ("both %<long%> and %<_Decimal128%> in "
7232 "declaration specifiers");
7234 specs->long_p = true;
7237 dupe = specs->short_p;
7239 error ("both %<long%> and %<short%> in "
7240 "declaration specifiers");
7241 else if (specs->typespec_word == cts_void)
7242 error ("both %<short%> and %<void%> in "
7243 "declaration specifiers");
7244 else if (specs->typespec_word == cts_bool)
7245 error ("both %<short%> and %<_Bool%> in "
7246 "declaration specifiers");
7247 else if (specs->typespec_word == cts_char)
7248 error ("both %<short%> and %<char%> in "
7249 "declaration specifiers");
7250 else if (specs->typespec_word == cts_float)
7251 error ("both %<short%> and %<float%> in "
7252 "declaration specifiers");
7253 else if (specs->typespec_word == cts_double)
7254 error ("both %<short%> and %<double%> in "
7255 "declaration specifiers");
7256 else if (specs->typespec_word == cts_dfloat32)
7257 error ("both %<short%> and %<_Decimal32%> in "
7258 "declaration specifiers");
7259 else if (specs->typespec_word == cts_dfloat64)
7260 error ("both %<short%> and %<_Decimal64%> in "
7261 "declaration specifiers");
7262 else if (specs->typespec_word == cts_dfloat128)
7263 error ("both %<short%> and %<_Decimal128%> in "
7264 "declaration specifiers");
7266 specs->short_p = true;
7269 dupe = specs->signed_p;
7270 if (specs->unsigned_p)
7271 error ("both %<signed%> and %<unsigned%> in "
7272 "declaration specifiers");
7273 else if (specs->typespec_word == cts_void)
7274 error ("both %<signed%> and %<void%> in "
7275 "declaration specifiers");
7276 else if (specs->typespec_word == cts_bool)
7277 error ("both %<signed%> and %<_Bool%> in "
7278 "declaration specifiers");
7279 else if (specs->typespec_word == cts_float)
7280 error ("both %<signed%> and %<float%> in "
7281 "declaration specifiers");
7282 else if (specs->typespec_word == cts_double)
7283 error ("both %<signed%> and %<double%> in "
7284 "declaration specifiers");
7285 else if (specs->typespec_word == cts_dfloat32)
7286 error ("both %<signed%> and %<_Decimal32%> in "
7287 "declaration specifiers");
7288 else if (specs->typespec_word == cts_dfloat64)
7289 error ("both %<signed%> and %<_Decimal64%> in "
7290 "declaration specifiers");
7291 else if (specs->typespec_word == cts_dfloat128)
7292 error ("both %<signed%> and %<_Decimal128%> in "
7293 "declaration specifiers");
7295 specs->signed_p = true;
7298 dupe = specs->unsigned_p;
7299 if (specs->signed_p)
7300 error ("both %<signed%> and %<unsigned%> in "
7301 "declaration specifiers");
7302 else if (specs->typespec_word == cts_void)
7303 error ("both %<unsigned%> and %<void%> in "
7304 "declaration specifiers");
7305 else if (specs->typespec_word == cts_bool)
7306 error ("both %<unsigned%> and %<_Bool%> in "
7307 "declaration specifiers");
7308 else if (specs->typespec_word == cts_float)
7309 error ("both %<unsigned%> and %<float%> in "
7310 "declaration specifiers");
7311 else if (specs->typespec_word == cts_double)
7312 error ("both %<unsigned%> and %<double%> in "
7313 "declaration specifiers");
7314 else if (specs->typespec_word == cts_dfloat32)
7315 error ("both %<unsigned%> and %<_Decimal32%> in "
7316 "declaration specifiers");
7317 else if (specs->typespec_word == cts_dfloat64)
7318 error ("both %<unsigned%> and %<_Decimal64%> in "
7319 "declaration specifiers");
7320 else if (specs->typespec_word == cts_dfloat128)
7321 error ("both %<unsigned%> and %<_Decimal128%> in "
7322 "declaration specifiers");
7324 specs->unsigned_p = true;
7327 dupe = specs->complex_p;
7328 if (pedantic && !flag_isoc99 && !in_system_header)
7329 pedwarn ("ISO C90 does not support complex types");
7330 if (specs->typespec_word == cts_void)
7331 error ("both %<complex%> and %<void%> in "
7332 "declaration specifiers");
7333 else if (specs->typespec_word == cts_bool)
7334 error ("both %<complex%> and %<_Bool%> in "
7335 "declaration specifiers");
7336 else if (specs->typespec_word == cts_dfloat32)
7337 error ("both %<complex%> and %<_Decimal32%> in "
7338 "declaration specifiers");
7339 else if (specs->typespec_word == cts_dfloat64)
7340 error ("both %<complex%> and %<_Decimal64%> in "
7341 "declaration specifiers");
7342 else if (specs->typespec_word == cts_dfloat128)
7343 error ("both %<complex%> and %<_Decimal128%> in "
7344 "declaration specifiers");
7346 specs->complex_p = true;
7353 error ("duplicate %qE", type);
7359 /* "void", "_Bool", "char", "int", "float" or "double". */
7360 if (specs->typespec_word != cts_none)
7362 error ("two or more data types in declaration specifiers");
7369 error ("both %<long%> and %<void%> in "
7370 "declaration specifiers");
7371 else if (specs->short_p)
7372 error ("both %<short%> and %<void%> in "
7373 "declaration specifiers");
7374 else if (specs->signed_p)
7375 error ("both %<signed%> and %<void%> in "
7376 "declaration specifiers");
7377 else if (specs->unsigned_p)
7378 error ("both %<unsigned%> and %<void%> in "
7379 "declaration specifiers");
7380 else if (specs->complex_p)
7381 error ("both %<complex%> and %<void%> in "
7382 "declaration specifiers");
7384 specs->typespec_word = cts_void;
7388 error ("both %<long%> and %<_Bool%> in "
7389 "declaration specifiers");
7390 else if (specs->short_p)
7391 error ("both %<short%> and %<_Bool%> in "
7392 "declaration specifiers");
7393 else if (specs->signed_p)
7394 error ("both %<signed%> and %<_Bool%> in "
7395 "declaration specifiers");
7396 else if (specs->unsigned_p)
7397 error ("both %<unsigned%> and %<_Bool%> in "
7398 "declaration specifiers");
7399 else if (specs->complex_p)
7400 error ("both %<complex%> and %<_Bool%> in "
7401 "declaration specifiers");
7403 specs->typespec_word = cts_bool;
7407 error ("both %<long%> and %<char%> in "
7408 "declaration specifiers");
7409 else if (specs->short_p)
7410 error ("both %<short%> and %<char%> in "
7411 "declaration specifiers");
7413 specs->typespec_word = cts_char;
7416 specs->typespec_word = cts_int;
7420 error ("both %<long%> and %<float%> in "
7421 "declaration specifiers");
7422 else if (specs->short_p)
7423 error ("both %<short%> and %<float%> in "
7424 "declaration specifiers");
7425 else if (specs->signed_p)
7426 error ("both %<signed%> and %<float%> in "
7427 "declaration specifiers");
7428 else if (specs->unsigned_p)
7429 error ("both %<unsigned%> and %<float%> in "
7430 "declaration specifiers");
7432 specs->typespec_word = cts_float;
7435 if (specs->long_long_p)
7436 error ("both %<long long%> and %<double%> in "
7437 "declaration specifiers");
7438 else if (specs->short_p)
7439 error ("both %<short%> and %<double%> in "
7440 "declaration specifiers");
7441 else if (specs->signed_p)
7442 error ("both %<signed%> and %<double%> in "
7443 "declaration specifiers");
7444 else if (specs->unsigned_p)
7445 error ("both %<unsigned%> and %<double%> in "
7446 "declaration specifiers");
7448 specs->typespec_word = cts_double;
7455 if (i == RID_DFLOAT32)
7457 else if (i == RID_DFLOAT64)
7460 str = "_Decimal128";
7461 if (specs->long_long_p)
7462 error ("both %<long long%> and %<%s%> in "
7463 "declaration specifiers", str);
7465 error ("both %<long%> and %<%s%> in "
7466 "declaration specifiers", str);
7467 else if (specs->short_p)
7468 error ("both %<short%> and %<%s%> in "
7469 "declaration specifiers", str);
7470 else if (specs->signed_p)
7471 error ("both %<signed%> and %<%s%> in "
7472 "declaration specifiers", str);
7473 else if (specs->unsigned_p)
7474 error ("both %<unsigned%> and %<%s%> in "
7475 "declaration specifiers", str);
7476 else if (specs->complex_p)
7477 error ("both %<complex%> and %<%s%> in "
7478 "declaration specifiers", str);
7479 else if (i == RID_DFLOAT32)
7480 specs->typespec_word = cts_dfloat32;
7481 else if (i == RID_DFLOAT64)
7482 specs->typespec_word = cts_dfloat64;
7484 specs->typespec_word = cts_dfloat128;
7486 if (!targetm.decimal_float_supported_p ())
7487 error ("decimal floating point not supported for this target");
7489 pedwarn ("ISO C does not support decimal floating point");
7492 /* ObjC reserved word "id", handled below. */
7498 /* Now we have a typedef (a TYPE_DECL node), an identifier (some
7499 form of ObjC type, cases such as "int" and "long" being handled
7500 above), a TYPE (struct, union, enum and typeof specifiers) or an
7501 ERROR_MARK. In none of these cases may there have previously
7502 been any type specifiers. */
7503 if (specs->type || specs->typespec_word != cts_none
7504 || specs->long_p || specs->short_p || specs->signed_p
7505 || specs->unsigned_p || specs->complex_p)
7506 error ("two or more data types in declaration specifiers");
7507 else if (TREE_CODE (type) == TYPE_DECL)
7509 if (TREE_TYPE (type) == error_mark_node)
7510 ; /* Allow the type to default to int to avoid cascading errors. */
7513 specs->type = TREE_TYPE (type);
7514 specs->decl_attr = DECL_ATTRIBUTES (type);
7515 specs->typedef_p = true;
7516 specs->explicit_signed_p = C_TYPEDEF_EXPLICITLY_SIGNED (type);
7519 else if (TREE_CODE (type) == IDENTIFIER_NODE)
7521 tree t = lookup_name (type);
7522 if (!t || TREE_CODE (t) != TYPE_DECL)
7523 error ("%qE fails to be a typedef or built in type", type);
7524 else if (TREE_TYPE (t) == error_mark_node)
7527 specs->type = TREE_TYPE (t);
7529 else if (TREE_CODE (type) != ERROR_MARK)
7531 if (spec.kind == ctsk_tagdef || spec.kind == ctsk_tagfirstref)
7532 specs->tag_defined_p = true;
7533 if (spec.kind == ctsk_typeof)
7534 specs->typedef_p = true;
7541 /* Add the storage class specifier or function specifier SCSPEC to the
7542 declaration specifiers SPECS, returning SPECS. */
7544 struct c_declspecs *
7545 declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
7548 enum c_storage_class n = csc_none;
7550 specs->declspecs_seen_p = true;
7551 gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
7552 && C_IS_RESERVED_WORD (scspec));
7553 i = C_RID_CODE (scspec);
7554 if (specs->non_sc_seen_p)
7555 warning (OPT_Wold_style_declaration,
7556 "%qE is not at beginning of declaration", scspec);
7560 /* C99 permits duplicate inline. Although of doubtful utility,
7561 it seems simplest to permit it in gnu89 mode as well, as
7562 there is also little utility in maintaining this as a
7563 difference between gnu89 and C99 inline. */
7565 specs->inline_p = true;
7568 dupe = specs->thread_p;
7569 if (specs->storage_class == csc_auto)
7570 error ("%<__thread%> used with %<auto%>");
7571 else if (specs->storage_class == csc_register)
7572 error ("%<__thread%> used with %<register%>");
7573 else if (specs->storage_class == csc_typedef)
7574 error ("%<__thread%> used with %<typedef%>");
7576 specs->thread_p = true;
7583 /* Diagnose "__thread extern". */
7584 if (specs->thread_p)
7585 error ("%<__thread%> before %<extern%>");
7592 /* Diagnose "__thread static". */
7593 if (specs->thread_p)
7594 error ("%<__thread%> before %<static%>");
7602 if (n != csc_none && n == specs->storage_class)
7605 error ("duplicate %qE", scspec);
7608 if (specs->storage_class != csc_none && n != specs->storage_class)
7610 error ("multiple storage classes in declaration specifiers");
7614 specs->storage_class = n;
7615 if (n != csc_extern && n != csc_static && specs->thread_p)
7617 error ("%<__thread%> used with %qE", scspec);
7618 specs->thread_p = false;
7625 /* Add the attributes ATTRS to the declaration specifiers SPECS,
7628 struct c_declspecs *
7629 declspecs_add_attrs (struct c_declspecs *specs, tree attrs)
7631 specs->attrs = chainon (attrs, specs->attrs);
7632 specs->declspecs_seen_p = true;
7636 /* Combine "long", "short", "signed", "unsigned" and "_Complex" type
7637 specifiers with any other type specifier to determine the resulting
7638 type. This is where ISO C checks on complex types are made, since
7639 "_Complex long" is a prefix of the valid ISO C type "_Complex long
7642 struct c_declspecs *
7643 finish_declspecs (struct c_declspecs *specs)
7645 /* If a type was specified as a whole, we have no modifiers and are
7647 if (specs->type != NULL_TREE)
7649 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7650 && !specs->signed_p && !specs->unsigned_p
7651 && !specs->complex_p);
7655 /* If none of "void", "_Bool", "char", "int", "float" or "double"
7656 has been specified, treat it as "int" unless "_Complex" is
7657 present and there are no other specifiers. If we just have
7658 "_Complex", it is equivalent to "_Complex double", but e.g.
7659 "_Complex short" is equivalent to "_Complex short int". */
7660 if (specs->typespec_word == cts_none)
7662 if (specs->long_p || specs->short_p
7663 || specs->signed_p || specs->unsigned_p)
7665 specs->typespec_word = cts_int;
7667 else if (specs->complex_p)
7669 specs->typespec_word = cts_double;
7671 pedwarn ("ISO C does not support plain %<complex%> meaning "
7672 "%<double complex%>");
7676 specs->typespec_word = cts_int;
7677 specs->default_int_p = true;
7678 /* We don't diagnose this here because grokdeclarator will
7679 give more specific diagnostics according to whether it is
7680 a function definition. */
7684 /* If "signed" was specified, record this to distinguish "int" and
7685 "signed int" in the case of a bit-field with
7686 -funsigned-bitfields. */
7687 specs->explicit_signed_p = specs->signed_p;
7689 /* Now compute the actual type. */
7690 switch (specs->typespec_word)
7693 gcc_assert (!specs->long_p && !specs->short_p
7694 && !specs->signed_p && !specs->unsigned_p
7695 && !specs->complex_p);
7696 specs->type = void_type_node;
7699 gcc_assert (!specs->long_p && !specs->short_p
7700 && !specs->signed_p && !specs->unsigned_p
7701 && !specs->complex_p);
7702 specs->type = boolean_type_node;
7705 gcc_assert (!specs->long_p && !specs->short_p);
7706 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7707 if (specs->signed_p)
7708 specs->type = signed_char_type_node;
7709 else if (specs->unsigned_p)
7710 specs->type = unsigned_char_type_node;
7712 specs->type = char_type_node;
7713 if (specs->complex_p)
7716 pedwarn ("ISO C does not support complex integer types");
7717 specs->type = build_complex_type (specs->type);
7721 gcc_assert (!(specs->long_p && specs->short_p));
7722 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7723 if (specs->long_long_p)
7724 specs->type = (specs->unsigned_p
7725 ? long_long_unsigned_type_node
7726 : long_long_integer_type_node);
7727 else if (specs->long_p)
7728 specs->type = (specs->unsigned_p
7729 ? long_unsigned_type_node
7730 : long_integer_type_node);
7731 else if (specs->short_p)
7732 specs->type = (specs->unsigned_p
7733 ? short_unsigned_type_node
7734 : short_integer_type_node);
7736 specs->type = (specs->unsigned_p
7737 ? unsigned_type_node
7738 : integer_type_node);
7739 if (specs->complex_p)
7742 pedwarn ("ISO C does not support complex integer types");
7743 specs->type = build_complex_type (specs->type);
7747 gcc_assert (!specs->long_p && !specs->short_p
7748 && !specs->signed_p && !specs->unsigned_p);
7749 specs->type = (specs->complex_p
7750 ? complex_float_type_node
7754 gcc_assert (!specs->long_long_p && !specs->short_p
7755 && !specs->signed_p && !specs->unsigned_p);
7758 specs->type = (specs->complex_p
7759 ? complex_long_double_type_node
7760 : long_double_type_node);
7764 specs->type = (specs->complex_p
7765 ? complex_double_type_node
7766 : double_type_node);
7772 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7773 && !specs->signed_p && !specs->unsigned_p && !specs->complex_p);
7774 if (specs->typespec_word == cts_dfloat32)
7775 specs->type = dfloat32_type_node;
7776 else if (specs->typespec_word == cts_dfloat64)
7777 specs->type = dfloat64_type_node;
7779 specs->type = dfloat128_type_node;
7788 /* A subroutine of c_write_global_declarations. Perform final processing
7789 on one file scope's declarations (or the external scope's declarations),
7793 c_write_global_declarations_1 (tree globals)
7798 /* Process the decls in the order they were written. */
7799 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7801 /* Check for used but undefined static functions using the C
7802 standard's definition of "used", and set TREE_NO_WARNING so
7803 that check_global_declarations doesn't repeat the check. */
7804 if (TREE_CODE (decl) == FUNCTION_DECL
7805 && DECL_INITIAL (decl) == 0
7806 && DECL_EXTERNAL (decl)
7807 && !TREE_PUBLIC (decl)
7808 && C_DECL_USED (decl))
7810 pedwarn ("%q+F used but never defined", decl);
7811 TREE_NO_WARNING (decl) = 1;
7814 wrapup_global_declaration_1 (decl);
7820 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7821 reconsider |= wrapup_global_declaration_2 (decl);
7825 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7826 check_global_declaration_1 (decl);
7829 /* A subroutine of c_write_global_declarations Emit debug information for each
7830 of the declarations in GLOBALS. */
7833 c_write_global_declarations_2 (tree globals)
7837 for (decl = globals; decl ; decl = TREE_CHAIN (decl))
7838 debug_hooks->global_decl (decl);
7841 /* Preserve the external declarations scope across a garbage collect. */
7842 static GTY(()) tree ext_block;
7845 c_write_global_declarations (void)
7849 /* We don't want to do this if generating a PCH. */
7853 /* Don't waste time on further processing if -fsyntax-only or we've
7854 encountered errors. */
7855 if (flag_syntax_only || errorcount || sorrycount || cpp_errors (parse_in))
7858 /* Close the external scope. */
7859 ext_block = pop_scope ();
7861 gcc_assert (!current_scope);
7865 tree tmp = BLOCK_VARS (ext_block);
7867 FILE * stream = dump_begin (TDI_tu, &flags);
7870 dump_node (tmp, flags & ~TDF_SLIM, stream);
7871 dump_end (TDI_tu, stream);
7875 /* Process all file scopes in this compilation, and the external_scope,
7876 through wrapup_global_declarations and check_global_declarations. */
7877 for (t = all_translation_units; t; t = TREE_CHAIN (t))
7878 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
7879 c_write_global_declarations_1 (BLOCK_VARS (ext_block));
7881 /* Call functions declared with the "constructor" or "destructor"
7883 c_build_cdtor_fns ();
7885 /* We're done parsing; proceed to optimize and emit assembly.
7886 FIXME: shouldn't be the front end's responsibility to call this. */
7889 /* After cgraph has had a chance to emit everything that's going to
7890 be emitted, output debug information for globals. */
7891 if (errorcount == 0 && sorrycount == 0)
7893 timevar_push (TV_SYMOUT);
7894 for (t = all_translation_units; t; t = TREE_CHAIN (t))
7895 c_write_global_declarations_2 (BLOCK_VARS (DECL_INITIAL (t)));
7896 c_write_global_declarations_2 (BLOCK_VARS (ext_block));
7897 timevar_pop (TV_SYMOUT);
7903 #include "gt-c-decl.h"