1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 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, 59 Temple Place - Suite 330, Boston, MA
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization. */
30 #include "coretypes.h"
34 #include "langhooks.h"
44 #include "tree-iterator.h"
45 #include "tree-gimple.h"
47 /* Possible cases of implicit bad conversions. Used to select
48 diagnostic messages in convert_for_assignment. */
57 /* The level of nesting inside "__alignof__". */
60 /* The level of nesting inside "sizeof". */
63 /* The level of nesting inside "typeof". */
66 /* Nonzero if we've already printed a "missing braces around initializer"
67 message within this initializer. */
68 static int missing_braces_mentioned;
70 static int require_constant_value;
71 static int require_constant_elements;
73 static tree qualify_type (tree, tree);
74 static int tagged_types_tu_compatible_p (tree, tree);
75 static int comp_target_types (tree, tree, int);
76 static int function_types_compatible_p (tree, tree);
77 static int type_lists_compatible_p (tree, tree);
78 static tree decl_constant_value_for_broken_optimization (tree);
79 static tree default_function_array_conversion (tree);
80 static tree lookup_field (tree, tree);
81 static tree convert_arguments (tree, tree, tree, tree);
82 static tree pointer_diff (tree, tree);
83 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
85 static tree valid_compound_expr_initializer (tree, tree);
86 static void push_string (const char *);
87 static void push_member_name (tree);
88 static void push_array_bounds (int);
89 static int spelling_length (void);
90 static char *print_spelling (char *);
91 static void warning_init (const char *);
92 static tree digest_init (tree, tree, bool, int);
93 static void output_init_element (tree, bool, tree, tree, int);
94 static void output_pending_init_elements (int);
95 static int set_designator (int);
96 static void push_range_stack (tree);
97 static void add_pending_init (tree, tree);
98 static void set_nonincremental_init (void);
99 static void set_nonincremental_init_from_string (tree);
100 static tree find_init_member (tree);
101 static void readonly_error (tree, enum lvalue_use);
102 static void record_maybe_used_decl (tree);
104 /* Do `exp = require_complete_type (exp);' to make sure exp
105 does not have an incomplete type. (That includes void types.) */
108 require_complete_type (tree value)
110 tree type = TREE_TYPE (value);
112 if (value == error_mark_node || type == error_mark_node)
113 return error_mark_node;
115 /* First, detect a valid value with a complete type. */
116 if (COMPLETE_TYPE_P (type))
119 c_incomplete_type_error (value, type);
120 return error_mark_node;
123 /* Print an error message for invalid use of an incomplete type.
124 VALUE is the expression that was used (or 0 if that isn't known)
125 and TYPE is the type that was invalid. */
128 c_incomplete_type_error (tree value, tree type)
130 const char *type_code_string;
132 /* Avoid duplicate error message. */
133 if (TREE_CODE (type) == ERROR_MARK)
136 if (value != 0 && (TREE_CODE (value) == VAR_DECL
137 || TREE_CODE (value) == PARM_DECL))
138 error ("%qs has an incomplete type",
139 IDENTIFIER_POINTER (DECL_NAME (value)));
143 /* We must print an error message. Be clever about what it says. */
145 switch (TREE_CODE (type))
148 type_code_string = "struct";
152 type_code_string = "union";
156 type_code_string = "enum";
160 error ("invalid use of void expression");
164 if (TYPE_DOMAIN (type))
166 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
168 error ("invalid use of flexible array member");
171 type = TREE_TYPE (type);
174 error ("invalid use of array with unspecified bounds");
181 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
182 error ("invalid use of undefined type %<%s %s%>",
183 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
185 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
186 error ("invalid use of incomplete typedef %qs",
187 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
191 /* Given a type, apply default promotions wrt unnamed function
192 arguments and return the new type. */
195 c_type_promotes_to (tree type)
197 if (TYPE_MAIN_VARIANT (type) == float_type_node)
198 return double_type_node;
200 if (c_promoting_integer_type_p (type))
202 /* Preserve unsignedness if not really getting any wider. */
203 if (TYPE_UNSIGNED (type)
204 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
205 return unsigned_type_node;
206 return integer_type_node;
212 /* Return a variant of TYPE which has all the type qualifiers of LIKE
213 as well as those of TYPE. */
216 qualify_type (tree type, tree like)
218 return c_build_qualified_type (type,
219 TYPE_QUALS (type) | TYPE_QUALS (like));
222 /* Return the composite type of two compatible types.
224 We assume that comptypes has already been done and returned
225 nonzero; if that isn't so, this may crash. In particular, we
226 assume that qualifiers match. */
229 composite_type (tree t1, tree t2)
231 enum tree_code code1;
232 enum tree_code code2;
235 /* Save time if the two types are the same. */
237 if (t1 == t2) return t1;
239 /* If one type is nonsense, use the other. */
240 if (t1 == error_mark_node)
242 if (t2 == error_mark_node)
245 code1 = TREE_CODE (t1);
246 code2 = TREE_CODE (t2);
248 /* Merge the attributes. */
249 attributes = targetm.merge_type_attributes (t1, t2);
251 /* If one is an enumerated type and the other is the compatible
252 integer type, the composite type might be either of the two
253 (DR#013 question 3). For consistency, use the enumerated type as
254 the composite type. */
256 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
258 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
261 gcc_assert (code1 == code2);
266 /* For two pointers, do this recursively on the target type. */
268 tree pointed_to_1 = TREE_TYPE (t1);
269 tree pointed_to_2 = TREE_TYPE (t2);
270 tree target = composite_type (pointed_to_1, pointed_to_2);
271 t1 = build_pointer_type (target);
272 t1 = build_type_attribute_variant (t1, attributes);
273 return qualify_type (t1, t2);
278 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
280 /* We should not have any type quals on arrays at all. */
281 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
283 /* Save space: see if the result is identical to one of the args. */
284 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
285 return build_type_attribute_variant (t1, attributes);
286 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
287 return build_type_attribute_variant (t2, attributes);
289 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
290 return build_type_attribute_variant (t1, attributes);
291 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
292 return build_type_attribute_variant (t2, attributes);
294 /* Merge the element types, and have a size if either arg has one. */
295 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
296 return build_type_attribute_variant (t1, attributes);
300 /* Function types: prefer the one that specified arg types.
301 If both do, merge the arg types. Also merge the return types. */
303 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
304 tree p1 = TYPE_ARG_TYPES (t1);
305 tree p2 = TYPE_ARG_TYPES (t2);
310 /* Save space: see if the result is identical to one of the args. */
311 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
312 return build_type_attribute_variant (t1, attributes);
313 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
314 return build_type_attribute_variant (t2, attributes);
316 /* Simple way if one arg fails to specify argument types. */
317 if (TYPE_ARG_TYPES (t1) == 0)
319 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
320 t1 = build_type_attribute_variant (t1, attributes);
321 return qualify_type (t1, t2);
323 if (TYPE_ARG_TYPES (t2) == 0)
325 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
326 t1 = build_type_attribute_variant (t1, attributes);
327 return qualify_type (t1, t2);
330 /* If both args specify argument types, we must merge the two
331 lists, argument by argument. */
332 /* Tell global_bindings_p to return false so that variable_size
333 doesn't abort on VLAs in parameter types. */
334 c_override_global_bindings_to_false = true;
336 len = list_length (p1);
339 for (i = 0; i < len; i++)
340 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
345 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
347 /* A null type means arg type is not specified.
348 Take whatever the other function type has. */
349 if (TREE_VALUE (p1) == 0)
351 TREE_VALUE (n) = TREE_VALUE (p2);
354 if (TREE_VALUE (p2) == 0)
356 TREE_VALUE (n) = TREE_VALUE (p1);
360 /* Given wait (union {union wait *u; int *i} *)
361 and wait (union wait *),
362 prefer union wait * as type of parm. */
363 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
364 && TREE_VALUE (p1) != TREE_VALUE (p2))
367 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
368 memb; memb = TREE_CHAIN (memb))
369 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2)))
371 TREE_VALUE (n) = TREE_VALUE (p2);
373 pedwarn ("function types not truly compatible in ISO C");
377 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
378 && TREE_VALUE (p2) != TREE_VALUE (p1))
381 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
382 memb; memb = TREE_CHAIN (memb))
383 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1)))
385 TREE_VALUE (n) = TREE_VALUE (p1);
387 pedwarn ("function types not truly compatible in ISO C");
391 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
395 c_override_global_bindings_to_false = false;
396 t1 = build_function_type (valtype, newargs);
397 t1 = qualify_type (t1, t2);
398 /* ... falls through ... */
402 return build_type_attribute_variant (t1, attributes);
407 /* Return the type of a conditional expression between pointers to
408 possibly differently qualified versions of compatible types.
410 We assume that comp_target_types has already been done and returned
411 nonzero; if that isn't so, this may crash. */
414 common_pointer_type (tree t1, tree t2)
421 /* Save time if the two types are the same. */
423 if (t1 == t2) return t1;
425 /* If one type is nonsense, use the other. */
426 if (t1 == error_mark_node)
428 if (t2 == error_mark_node)
431 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
432 && TREE_CODE (t2) == POINTER_TYPE);
434 /* Merge the attributes. */
435 attributes = targetm.merge_type_attributes (t1, t2);
437 /* Find the composite type of the target types, and combine the
438 qualifiers of the two types' targets. */
439 pointed_to_1 = TREE_TYPE (t1);
440 pointed_to_2 = TREE_TYPE (t2);
441 target = composite_type (TYPE_MAIN_VARIANT (pointed_to_1),
442 TYPE_MAIN_VARIANT (pointed_to_2));
443 t1 = build_pointer_type (c_build_qualified_type
445 TYPE_QUALS (pointed_to_1) |
446 TYPE_QUALS (pointed_to_2)));
447 return build_type_attribute_variant (t1, attributes);
450 /* Return the common type for two arithmetic types under the usual
451 arithmetic conversions. The default conversions have already been
452 applied, and enumerated types converted to their compatible integer
453 types. The resulting type is unqualified and has no attributes.
455 This is the type for the result of most arithmetic operations
456 if the operands have the given two types. */
459 common_type (tree t1, tree t2)
461 enum tree_code code1;
462 enum tree_code code2;
464 /* If one type is nonsense, use the other. */
465 if (t1 == error_mark_node)
467 if (t2 == error_mark_node)
470 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
471 t1 = TYPE_MAIN_VARIANT (t1);
473 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
474 t2 = TYPE_MAIN_VARIANT (t2);
476 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
477 t1 = build_type_attribute_variant (t1, NULL_TREE);
479 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
480 t2 = build_type_attribute_variant (t2, NULL_TREE);
482 /* Save time if the two types are the same. */
484 if (t1 == t2) return t1;
486 code1 = TREE_CODE (t1);
487 code2 = TREE_CODE (t2);
489 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
490 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
491 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
492 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
494 /* If one type is a vector type, return that type. (How the usual
495 arithmetic conversions apply to the vector types extension is not
496 precisely specified.) */
497 if (code1 == VECTOR_TYPE)
500 if (code2 == VECTOR_TYPE)
503 /* If one type is complex, form the common type of the non-complex
504 components, then make that complex. Use T1 or T2 if it is the
506 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
508 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
509 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
510 tree subtype = common_type (subtype1, subtype2);
512 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
514 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
517 return build_complex_type (subtype);
520 /* If only one is real, use it as the result. */
522 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
525 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
528 /* Both real or both integers; use the one with greater precision. */
530 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
532 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
535 /* Same precision. Prefer long longs to longs to ints when the
536 same precision, following the C99 rules on integer type rank
537 (which are equivalent to the C90 rules for C90 types). */
539 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
540 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
541 return long_long_unsigned_type_node;
543 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
544 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
546 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
547 return long_long_unsigned_type_node;
549 return long_long_integer_type_node;
552 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
553 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
554 return long_unsigned_type_node;
556 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
557 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
559 /* But preserve unsignedness from the other type,
560 since long cannot hold all the values of an unsigned int. */
561 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
562 return long_unsigned_type_node;
564 return long_integer_type_node;
567 /* Likewise, prefer long double to double even if same size. */
568 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
569 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
570 return long_double_type_node;
572 /* Otherwise prefer the unsigned one. */
574 if (TYPE_UNSIGNED (t1))
580 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
581 or various other operations. Return 2 if they are compatible
582 but a warning may be needed if you use them together. */
585 comptypes (tree type1, tree type2)
591 /* Suppress errors caused by previously reported errors. */
593 if (t1 == t2 || !t1 || !t2
594 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
597 /* If either type is the internal version of sizetype, return the
599 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
600 && TYPE_ORIG_SIZE_TYPE (t1))
601 t1 = TYPE_ORIG_SIZE_TYPE (t1);
603 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
604 && TYPE_ORIG_SIZE_TYPE (t2))
605 t2 = TYPE_ORIG_SIZE_TYPE (t2);
608 /* Enumerated types are compatible with integer types, but this is
609 not transitive: two enumerated types in the same translation unit
610 are compatible with each other only if they are the same type. */
612 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
613 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
614 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
615 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
620 /* Different classes of types can't be compatible. */
622 if (TREE_CODE (t1) != TREE_CODE (t2))
625 /* Qualifiers must match. C99 6.7.3p9 */
627 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
630 /* Allow for two different type nodes which have essentially the same
631 definition. Note that we already checked for equality of the type
632 qualifiers (just above). */
634 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
637 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
638 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
641 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
644 switch (TREE_CODE (t1))
647 /* We must give ObjC the first crack at comparing pointers, since
648 protocol qualifiers may be involved. */
649 if (c_dialect_objc () && (val = objc_comptypes (t1, t2, 0)) >= 0)
651 /* Do not remove mode or aliasing information. */
652 if (TYPE_MODE (t1) != TYPE_MODE (t2)
653 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
655 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
656 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
660 val = function_types_compatible_p (t1, t2);
665 tree d1 = TYPE_DOMAIN (t1);
666 tree d2 = TYPE_DOMAIN (t2);
667 bool d1_variable, d2_variable;
668 bool d1_zero, d2_zero;
671 /* Target types must match incl. qualifiers. */
672 if (TREE_TYPE (t1) != TREE_TYPE (t2)
673 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
676 /* Sizes must match unless one is missing or variable. */
677 if (d1 == 0 || d2 == 0 || d1 == d2)
680 d1_zero = !TYPE_MAX_VALUE (d1);
681 d2_zero = !TYPE_MAX_VALUE (d2);
683 d1_variable = (!d1_zero
684 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
685 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
686 d2_variable = (!d2_zero
687 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
688 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
690 if (d1_variable || d2_variable)
692 if (d1_zero && d2_zero)
694 if (d1_zero || d2_zero
695 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
696 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
703 /* We are dealing with two distinct structs. In assorted Objective-C
704 corner cases, however, these can still be deemed equivalent. */
705 if (c_dialect_objc () && objc_comptypes (t1, t2, 0) == 1)
710 if (val != 1 && !same_translation_unit_p (t1, t2))
711 val = tagged_types_tu_compatible_p (t1, t2);
715 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
716 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2));
722 return attrval == 2 && val == 1 ? 2 : val;
725 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
726 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
727 to 1 or 0 depending if the check of the pointer types is meant to
728 be reflexive or not (typically, assignments are not reflexive,
729 while comparisons are reflexive).
733 comp_target_types (tree ttl, tree ttr, int reflexive)
737 /* Give objc_comptypes a crack at letting these types through. */
738 if ((val = objc_comptypes (ttl, ttr, reflexive)) >= 0)
741 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
742 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)));
744 if (val == 2 && pedantic)
745 pedwarn ("types are not quite compatible");
749 /* Subroutines of `comptypes'. */
751 /* Determine whether two trees derive from the same translation unit.
752 If the CONTEXT chain ends in a null, that tree's context is still
753 being parsed, so if two trees have context chains ending in null,
754 they're in the same translation unit. */
756 same_translation_unit_p (tree t1, tree t2)
758 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
759 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
761 case tcc_declaration:
762 t1 = DECL_CONTEXT (t1); break;
764 t1 = TYPE_CONTEXT (t1); break;
765 case tcc_exceptional:
766 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
767 default: gcc_unreachable ();
770 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
771 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
773 case tcc_declaration:
774 t2 = DECL_CONTEXT (t2); break;
776 t2 = TYPE_CONTEXT (t2); break;
777 case tcc_exceptional:
778 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
779 default: gcc_unreachable ();
785 /* The C standard says that two structures in different translation
786 units are compatible with each other only if the types of their
787 fields are compatible (among other things). So, consider two copies
788 of this structure: */
790 struct tagged_tu_seen {
791 const struct tagged_tu_seen * next;
796 /* Can they be compatible with each other? We choose to break the
797 recursion by allowing those types to be compatible. */
799 static const struct tagged_tu_seen * tagged_tu_seen_base;
801 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
802 compatible. If the two types are not the same (which has been
803 checked earlier), this can only happen when multiple translation
804 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
808 tagged_types_tu_compatible_p (tree t1, tree t2)
811 bool needs_warning = false;
813 /* We have to verify that the tags of the types are the same. This
814 is harder than it looks because this may be a typedef, so we have
815 to go look at the original type. It may even be a typedef of a
817 In the case of compiler-created builtin structs the TYPE_DECL
818 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
819 while (TYPE_NAME (t1)
820 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
821 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
822 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
824 while (TYPE_NAME (t2)
825 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
826 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
827 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
829 /* C90 didn't have the requirement that the two tags be the same. */
830 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
833 /* C90 didn't say what happened if one or both of the types were
834 incomplete; we choose to follow C99 rules here, which is that they
836 if (TYPE_SIZE (t1) == NULL
837 || TYPE_SIZE (t2) == NULL)
841 const struct tagged_tu_seen * tts_i;
842 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
843 if (tts_i->t1 == t1 && tts_i->t2 == t2)
847 switch (TREE_CODE (t1))
852 /* Speed up the case where the type values are in the same order. */
853 tree tv1 = TYPE_VALUES (t1);
854 tree tv2 = TYPE_VALUES (t2);
859 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
861 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
863 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
867 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
869 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
872 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
875 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
877 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
879 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
887 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
890 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
893 struct tagged_tu_seen tts;
895 tts.next = tagged_tu_seen_base;
898 tagged_tu_seen_base = &tts;
900 if (DECL_NAME (s1) != NULL)
901 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
902 if (DECL_NAME (s1) == DECL_NAME (s2))
905 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
909 needs_warning = true;
911 if (TREE_CODE (s1) == FIELD_DECL
912 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
913 DECL_FIELD_BIT_OFFSET (s2)) != 1)
919 tagged_tu_seen_base = tts.next;
923 return needs_warning ? 2 : 1;
928 struct tagged_tu_seen tts;
930 tts.next = tagged_tu_seen_base;
933 tagged_tu_seen_base = &tts;
935 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
937 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
940 if (TREE_CODE (s1) != TREE_CODE (s2)
941 || DECL_NAME (s1) != DECL_NAME (s2))
943 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
947 needs_warning = true;
949 if (TREE_CODE (s1) == FIELD_DECL
950 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
951 DECL_FIELD_BIT_OFFSET (s2)) != 1)
954 tagged_tu_seen_base = tts.next;
957 return needs_warning ? 2 : 1;
965 /* Return 1 if two function types F1 and F2 are compatible.
966 If either type specifies no argument types,
967 the other must specify a fixed number of self-promoting arg types.
968 Otherwise, if one type specifies only the number of arguments,
969 the other must specify that number of self-promoting arg types.
970 Otherwise, the argument types must match. */
973 function_types_compatible_p (tree f1, tree f2)
976 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
981 ret1 = TREE_TYPE (f1);
982 ret2 = TREE_TYPE (f2);
984 /* 'volatile' qualifiers on a function's return type used to mean
985 the function is noreturn. */
986 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
987 pedwarn ("function return types not compatible due to %<volatile%>");
988 if (TYPE_VOLATILE (ret1))
989 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
990 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
991 if (TYPE_VOLATILE (ret2))
992 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
993 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
994 val = comptypes (ret1, ret2);
998 args1 = TYPE_ARG_TYPES (f1);
999 args2 = TYPE_ARG_TYPES (f2);
1001 /* An unspecified parmlist matches any specified parmlist
1002 whose argument types don't need default promotions. */
1006 if (!self_promoting_args_p (args2))
1008 /* If one of these types comes from a non-prototype fn definition,
1009 compare that with the other type's arglist.
1010 If they don't match, ask for a warning (but no error). */
1011 if (TYPE_ACTUAL_ARG_TYPES (f1)
1012 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1018 if (!self_promoting_args_p (args1))
1020 if (TYPE_ACTUAL_ARG_TYPES (f2)
1021 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1026 /* Both types have argument lists: compare them and propagate results. */
1027 val1 = type_lists_compatible_p (args1, args2);
1028 return val1 != 1 ? val1 : val;
1031 /* Check two lists of types for compatibility,
1032 returning 0 for incompatible, 1 for compatible,
1033 or 2 for compatible with warning. */
1036 type_lists_compatible_p (tree args1, tree args2)
1038 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1044 if (args1 == 0 && args2 == 0)
1046 /* If one list is shorter than the other,
1047 they fail to match. */
1048 if (args1 == 0 || args2 == 0)
1050 /* A null pointer instead of a type
1051 means there is supposed to be an argument
1052 but nothing is specified about what type it has.
1053 So match anything that self-promotes. */
1054 if (TREE_VALUE (args1) == 0)
1056 if (c_type_promotes_to (TREE_VALUE (args2)) != TREE_VALUE (args2))
1059 else if (TREE_VALUE (args2) == 0)
1061 if (c_type_promotes_to (TREE_VALUE (args1)) != TREE_VALUE (args1))
1064 /* If one of the lists has an error marker, ignore this arg. */
1065 else if (TREE_CODE (TREE_VALUE (args1)) == ERROR_MARK
1066 || TREE_CODE (TREE_VALUE (args2)) == ERROR_MARK)
1068 else if (!(newval = comptypes (TYPE_MAIN_VARIANT (TREE_VALUE (args1)),
1069 TYPE_MAIN_VARIANT (TREE_VALUE (args2)))))
1071 /* Allow wait (union {union wait *u; int *i} *)
1072 and wait (union wait *) to be compatible. */
1073 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
1074 && (TYPE_NAME (TREE_VALUE (args1)) == 0
1075 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
1076 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
1077 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
1078 TYPE_SIZE (TREE_VALUE (args2))))
1081 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
1082 memb; memb = TREE_CHAIN (memb))
1083 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2)))
1088 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
1089 && (TYPE_NAME (TREE_VALUE (args2)) == 0
1090 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
1091 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
1092 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
1093 TYPE_SIZE (TREE_VALUE (args1))))
1096 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
1097 memb; memb = TREE_CHAIN (memb))
1098 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1)))
1107 /* comptypes said ok, but record if it said to warn. */
1111 args1 = TREE_CHAIN (args1);
1112 args2 = TREE_CHAIN (args2);
1116 /* Compute the size to increment a pointer by. */
1119 c_size_in_bytes (tree type)
1121 enum tree_code code = TREE_CODE (type);
1123 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1124 return size_one_node;
1126 if (!COMPLETE_OR_VOID_TYPE_P (type))
1128 error ("arithmetic on pointer to an incomplete type");
1129 return size_one_node;
1132 /* Convert in case a char is more than one unit. */
1133 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1134 size_int (TYPE_PRECISION (char_type_node)
1138 /* Return either DECL or its known constant value (if it has one). */
1141 decl_constant_value (tree decl)
1143 if (/* Don't change a variable array bound or initial value to a constant
1144 in a place where a variable is invalid. Note that DECL_INITIAL
1145 isn't valid for a PARM_DECL. */
1146 current_function_decl != 0
1147 && TREE_CODE (decl) != PARM_DECL
1148 && !TREE_THIS_VOLATILE (decl)
1149 && TREE_READONLY (decl)
1150 && DECL_INITIAL (decl) != 0
1151 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1152 /* This is invalid if initial value is not constant.
1153 If it has either a function call, a memory reference,
1154 or a variable, then re-evaluating it could give different results. */
1155 && TREE_CONSTANT (DECL_INITIAL (decl))
1156 /* Check for cases where this is sub-optimal, even though valid. */
1157 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1158 return DECL_INITIAL (decl);
1162 /* Return either DECL or its known constant value (if it has one), but
1163 return DECL if pedantic or DECL has mode BLKmode. This is for
1164 bug-compatibility with the old behavior of decl_constant_value
1165 (before GCC 3.0); every use of this function is a bug and it should
1166 be removed before GCC 3.1. It is not appropriate to use pedantic
1167 in a way that affects optimization, and BLKmode is probably not the
1168 right test for avoiding misoptimizations either. */
1171 decl_constant_value_for_broken_optimization (tree decl)
1173 if (pedantic || DECL_MODE (decl) == BLKmode)
1176 return decl_constant_value (decl);
1180 /* Perform the default conversion of arrays and functions to pointers.
1181 Return the result of converting EXP. For any other expression, just
1185 default_function_array_conversion (tree exp)
1188 tree type = TREE_TYPE (exp);
1189 enum tree_code code = TREE_CODE (type);
1192 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1195 Do not use STRIP_NOPS here! It will remove conversions from pointer
1196 to integer and cause infinite recursion. */
1198 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1199 || (TREE_CODE (exp) == NOP_EXPR
1200 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1202 if (TREE_CODE (exp) == NON_LVALUE_EXPR)
1204 exp = TREE_OPERAND (exp, 0);
1207 if (TREE_NO_WARNING (orig_exp))
1208 TREE_NO_WARNING (exp) = 1;
1210 if (code == FUNCTION_TYPE)
1212 return build_unary_op (ADDR_EXPR, exp, 0);
1214 if (code == ARRAY_TYPE)
1217 tree restype = TREE_TYPE (type);
1223 if (REFERENCE_CLASS_P (exp) || DECL_P (exp))
1225 constp = TREE_READONLY (exp);
1226 volatilep = TREE_THIS_VOLATILE (exp);
1229 if (TYPE_QUALS (type) || constp || volatilep)
1231 = c_build_qualified_type (restype,
1233 | (constp * TYPE_QUAL_CONST)
1234 | (volatilep * TYPE_QUAL_VOLATILE));
1236 if (TREE_CODE (exp) == INDIRECT_REF)
1237 return convert (build_pointer_type (restype),
1238 TREE_OPERAND (exp, 0));
1240 if (TREE_CODE (exp) == COMPOUND_EXPR)
1242 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1243 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1244 TREE_OPERAND (exp, 0), op1);
1247 lvalue_array_p = !not_lvalue && lvalue_p (exp);
1248 if (!flag_isoc99 && !lvalue_array_p)
1250 /* Before C99, non-lvalue arrays do not decay to pointers.
1251 Normally, using such an array would be invalid; but it can
1252 be used correctly inside sizeof or as a statement expression.
1253 Thus, do not give an error here; an error will result later. */
1257 ptrtype = build_pointer_type (restype);
1259 if (TREE_CODE (exp) == VAR_DECL)
1261 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1262 ADDR_EXPR because it's the best way of representing what
1263 happens in C when we take the address of an array and place
1264 it in a pointer to the element type. */
1265 adr = build1 (ADDR_EXPR, ptrtype, exp);
1266 if (!c_mark_addressable (exp))
1267 return error_mark_node;
1268 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1271 /* This way is better for a COMPONENT_REF since it can
1272 simplify the offset for a component. */
1273 adr = build_unary_op (ADDR_EXPR, exp, 1);
1274 return convert (ptrtype, adr);
1279 /* Perform default promotions for C data used in expressions.
1280 Arrays and functions are converted to pointers;
1281 enumeral types or short or char, to int.
1282 In addition, manifest constants symbols are replaced by their values. */
1285 default_conversion (tree exp)
1288 tree type = TREE_TYPE (exp);
1289 enum tree_code code = TREE_CODE (type);
1291 if (code == FUNCTION_TYPE || code == ARRAY_TYPE)
1292 return default_function_array_conversion (exp);
1294 /* Constants can be used directly unless they're not loadable. */
1295 if (TREE_CODE (exp) == CONST_DECL)
1296 exp = DECL_INITIAL (exp);
1298 /* Replace a nonvolatile const static variable with its value unless
1299 it is an array, in which case we must be sure that taking the
1300 address of the array produces consistent results. */
1301 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1303 exp = decl_constant_value_for_broken_optimization (exp);
1304 type = TREE_TYPE (exp);
1307 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1310 Do not use STRIP_NOPS here! It will remove conversions from pointer
1311 to integer and cause infinite recursion. */
1313 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1314 || (TREE_CODE (exp) == NOP_EXPR
1315 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1316 exp = TREE_OPERAND (exp, 0);
1318 if (TREE_NO_WARNING (orig_exp))
1319 TREE_NO_WARNING (exp) = 1;
1321 /* Normally convert enums to int,
1322 but convert wide enums to something wider. */
1323 if (code == ENUMERAL_TYPE)
1325 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1326 TYPE_PRECISION (integer_type_node)),
1327 ((TYPE_PRECISION (type)
1328 >= TYPE_PRECISION (integer_type_node))
1329 && TYPE_UNSIGNED (type)));
1331 return convert (type, exp);
1334 if (TREE_CODE (exp) == COMPONENT_REF
1335 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1336 /* If it's thinner than an int, promote it like a
1337 c_promoting_integer_type_p, otherwise leave it alone. */
1338 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1339 TYPE_PRECISION (integer_type_node)))
1340 return convert (integer_type_node, exp);
1342 if (c_promoting_integer_type_p (type))
1344 /* Preserve unsignedness if not really getting any wider. */
1345 if (TYPE_UNSIGNED (type)
1346 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1347 return convert (unsigned_type_node, exp);
1349 return convert (integer_type_node, exp);
1352 if (code == VOID_TYPE)
1354 error ("void value not ignored as it ought to be");
1355 return error_mark_node;
1360 /* Look up COMPONENT in a structure or union DECL.
1362 If the component name is not found, returns NULL_TREE. Otherwise,
1363 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1364 stepping down the chain to the component, which is in the last
1365 TREE_VALUE of the list. Normally the list is of length one, but if
1366 the component is embedded within (nested) anonymous structures or
1367 unions, the list steps down the chain to the component. */
1370 lookup_field (tree decl, tree component)
1372 tree type = TREE_TYPE (decl);
1375 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1376 to the field elements. Use a binary search on this array to quickly
1377 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1378 will always be set for structures which have many elements. */
1380 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1383 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1385 field = TYPE_FIELDS (type);
1387 top = TYPE_LANG_SPECIFIC (type)->s->len;
1388 while (top - bot > 1)
1390 half = (top - bot + 1) >> 1;
1391 field = field_array[bot+half];
1393 if (DECL_NAME (field) == NULL_TREE)
1395 /* Step through all anon unions in linear fashion. */
1396 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1398 field = field_array[bot++];
1399 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1400 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1402 tree anon = lookup_field (field, component);
1405 return tree_cons (NULL_TREE, field, anon);
1409 /* Entire record is only anon unions. */
1413 /* Restart the binary search, with new lower bound. */
1417 if (DECL_NAME (field) == component)
1419 if (DECL_NAME (field) < component)
1425 if (DECL_NAME (field_array[bot]) == component)
1426 field = field_array[bot];
1427 else if (DECL_NAME (field) != component)
1432 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1434 if (DECL_NAME (field) == NULL_TREE
1435 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1436 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1438 tree anon = lookup_field (field, component);
1441 return tree_cons (NULL_TREE, field, anon);
1444 if (DECL_NAME (field) == component)
1448 if (field == NULL_TREE)
1452 return tree_cons (NULL_TREE, field, NULL_TREE);
1455 /* Make an expression to refer to the COMPONENT field of
1456 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1459 build_component_ref (tree datum, tree component)
1461 tree type = TREE_TYPE (datum);
1462 enum tree_code code = TREE_CODE (type);
1466 if (!objc_is_public (datum, component))
1467 return error_mark_node;
1469 /* See if there is a field or component with name COMPONENT. */
1471 if (code == RECORD_TYPE || code == UNION_TYPE)
1473 if (!COMPLETE_TYPE_P (type))
1475 c_incomplete_type_error (NULL_TREE, type);
1476 return error_mark_node;
1479 field = lookup_field (datum, component);
1483 error ("%qT has no member named %qs", type,
1484 IDENTIFIER_POINTER (component));
1485 return error_mark_node;
1488 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1489 This might be better solved in future the way the C++ front
1490 end does it - by giving the anonymous entities each a
1491 separate name and type, and then have build_component_ref
1492 recursively call itself. We can't do that here. */
1495 tree subdatum = TREE_VALUE (field);
1497 if (TREE_TYPE (subdatum) == error_mark_node)
1498 return error_mark_node;
1500 ref = build3 (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum,
1502 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1503 TREE_READONLY (ref) = 1;
1504 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1505 TREE_THIS_VOLATILE (ref) = 1;
1507 if (TREE_DEPRECATED (subdatum))
1508 warn_deprecated_use (subdatum);
1512 field = TREE_CHAIN (field);
1518 else if (code != ERROR_MARK)
1519 error ("request for member %qs in something not a structure or union",
1520 IDENTIFIER_POINTER (component));
1522 return error_mark_node;
1525 /* Given an expression PTR for a pointer, return an expression
1526 for the value pointed to.
1527 ERRORSTRING is the name of the operator to appear in error messages. */
1530 build_indirect_ref (tree ptr, const char *errorstring)
1532 tree pointer = default_conversion (ptr);
1533 tree type = TREE_TYPE (pointer);
1535 if (TREE_CODE (type) == POINTER_TYPE)
1537 if (TREE_CODE (pointer) == ADDR_EXPR
1538 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1539 == TREE_TYPE (type)))
1540 return TREE_OPERAND (pointer, 0);
1543 tree t = TREE_TYPE (type);
1544 tree ref = build1 (INDIRECT_REF, TYPE_MAIN_VARIANT (t), pointer);
1546 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1548 error ("dereferencing pointer to incomplete type");
1549 return error_mark_node;
1551 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1552 warning ("dereferencing %<void *%> pointer");
1554 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1555 so that we get the proper error message if the result is used
1556 to assign to. Also, &* is supposed to be a no-op.
1557 And ANSI C seems to specify that the type of the result
1558 should be the const type. */
1559 /* A de-reference of a pointer to const is not a const. It is valid
1560 to change it via some other pointer. */
1561 TREE_READONLY (ref) = TYPE_READONLY (t);
1562 TREE_SIDE_EFFECTS (ref)
1563 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1564 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1568 else if (TREE_CODE (pointer) != ERROR_MARK)
1569 error ("invalid type argument of %qs", errorstring);
1570 return error_mark_node;
1573 /* This handles expressions of the form "a[i]", which denotes
1576 This is logically equivalent in C to *(a+i), but we may do it differently.
1577 If A is a variable or a member, we generate a primitive ARRAY_REF.
1578 This avoids forcing the array out of registers, and can work on
1579 arrays that are not lvalues (for example, members of structures returned
1583 build_array_ref (tree array, tree index)
1585 bool swapped = false;
1586 if (TREE_TYPE (array) == error_mark_node
1587 || TREE_TYPE (index) == error_mark_node)
1588 return error_mark_node;
1590 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1591 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1594 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1595 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1597 error ("subscripted value is neither array nor pointer");
1598 return error_mark_node;
1606 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1608 error ("array subscript is not an integer");
1609 return error_mark_node;
1612 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1614 error ("subscripted value is pointer to function");
1615 return error_mark_node;
1618 /* Subscripting with type char is likely to lose on a machine where
1619 chars are signed. So warn on any machine, but optionally. Don't
1620 warn for unsigned char since that type is safe. Don't warn for
1621 signed char because anyone who uses that must have done so
1622 deliberately. ??? Existing practice has also been to warn only
1623 when the char index is syntactically the index, not for
1625 if (warn_char_subscripts && !swapped
1626 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1627 warning ("array subscript has type %<char%>");
1629 /* Apply default promotions *after* noticing character types. */
1630 index = default_conversion (index);
1632 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1634 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1638 /* An array that is indexed by a non-constant
1639 cannot be stored in a register; we must be able to do
1640 address arithmetic on its address.
1641 Likewise an array of elements of variable size. */
1642 if (TREE_CODE (index) != INTEGER_CST
1643 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1644 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1646 if (!c_mark_addressable (array))
1647 return error_mark_node;
1649 /* An array that is indexed by a constant value which is not within
1650 the array bounds cannot be stored in a register either; because we
1651 would get a crash in store_bit_field/extract_bit_field when trying
1652 to access a non-existent part of the register. */
1653 if (TREE_CODE (index) == INTEGER_CST
1654 && TYPE_DOMAIN (TREE_TYPE (array))
1655 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1657 if (!c_mark_addressable (array))
1658 return error_mark_node;
1664 while (TREE_CODE (foo) == COMPONENT_REF)
1665 foo = TREE_OPERAND (foo, 0);
1666 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1667 pedwarn ("ISO C forbids subscripting %<register%> array");
1668 else if (!flag_isoc99 && !lvalue_p (foo))
1669 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1672 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1673 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
1674 /* Array ref is const/volatile if the array elements are
1675 or if the array is. */
1676 TREE_READONLY (rval)
1677 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1678 | TREE_READONLY (array));
1679 TREE_SIDE_EFFECTS (rval)
1680 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1681 | TREE_SIDE_EFFECTS (array));
1682 TREE_THIS_VOLATILE (rval)
1683 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1684 /* This was added by rms on 16 Nov 91.
1685 It fixes vol struct foo *a; a->elts[1]
1686 in an inline function.
1687 Hope it doesn't break something else. */
1688 | TREE_THIS_VOLATILE (array));
1689 return require_complete_type (fold (rval));
1693 tree ar = default_conversion (array);
1695 if (ar == error_mark_node)
1698 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
1699 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
1701 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
1706 /* Build an external reference to identifier ID. FUN indicates
1707 whether this will be used for a function call. */
1709 build_external_ref (tree id, int fun)
1712 tree decl = lookup_name (id);
1714 /* In Objective-C, an instance variable (ivar) may be preferred to
1715 whatever lookup_name() found. */
1716 decl = objc_lookup_ivar (decl, id);
1718 if (decl && decl != error_mark_node)
1721 /* Implicit function declaration. */
1722 ref = implicitly_declare (id);
1723 else if (decl == error_mark_node)
1724 /* Don't complain about something that's already been
1725 complained about. */
1726 return error_mark_node;
1729 undeclared_variable (id);
1730 return error_mark_node;
1733 if (TREE_TYPE (ref) == error_mark_node)
1734 return error_mark_node;
1736 if (TREE_DEPRECATED (ref))
1737 warn_deprecated_use (ref);
1739 if (!skip_evaluation)
1740 assemble_external (ref);
1741 TREE_USED (ref) = 1;
1743 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
1745 if (!in_sizeof && !in_typeof)
1746 C_DECL_USED (ref) = 1;
1747 else if (DECL_INITIAL (ref) == 0
1748 && DECL_EXTERNAL (ref)
1749 && !TREE_PUBLIC (ref))
1750 record_maybe_used_decl (ref);
1753 if (TREE_CODE (ref) == CONST_DECL)
1755 ref = DECL_INITIAL (ref);
1756 TREE_CONSTANT (ref) = 1;
1757 TREE_INVARIANT (ref) = 1;
1759 else if (current_function_decl != 0
1760 && !DECL_FILE_SCOPE_P (current_function_decl)
1761 && (TREE_CODE (ref) == VAR_DECL
1762 || TREE_CODE (ref) == PARM_DECL
1763 || TREE_CODE (ref) == FUNCTION_DECL))
1765 tree context = decl_function_context (ref);
1767 if (context != 0 && context != current_function_decl)
1768 DECL_NONLOCAL (ref) = 1;
1774 /* Record details of decls possibly used inside sizeof or typeof. */
1775 struct maybe_used_decl
1779 /* The level seen at (in_sizeof + in_typeof). */
1781 /* The next one at this level or above, or NULL. */
1782 struct maybe_used_decl *next;
1785 static struct maybe_used_decl *maybe_used_decls;
1787 /* Record that DECL, an undefined static function reference seen
1788 inside sizeof or typeof, might be used if the operand of sizeof is
1789 a VLA type or the operand of typeof is a variably modified
1793 record_maybe_used_decl (tree decl)
1795 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
1797 t->level = in_sizeof + in_typeof;
1798 t->next = maybe_used_decls;
1799 maybe_used_decls = t;
1802 /* Pop the stack of decls possibly used inside sizeof or typeof. If
1803 USED is false, just discard them. If it is true, mark them used
1804 (if no longer inside sizeof or typeof) or move them to the next
1805 level up (if still inside sizeof or typeof). */
1808 pop_maybe_used (bool used)
1810 struct maybe_used_decl *p = maybe_used_decls;
1811 int cur_level = in_sizeof + in_typeof;
1812 while (p && p->level > cur_level)
1817 C_DECL_USED (p->decl) = 1;
1819 p->level = cur_level;
1823 if (!used || cur_level == 0)
1824 maybe_used_decls = p;
1827 /* Return the result of sizeof applied to EXPR. */
1830 c_expr_sizeof_expr (struct c_expr expr)
1833 if (expr.value == error_mark_node)
1835 ret.value = error_mark_node;
1836 ret.original_code = ERROR_MARK;
1837 pop_maybe_used (false);
1841 ret.value = c_sizeof (TREE_TYPE (expr.value));
1842 ret.original_code = ERROR_MARK;
1843 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
1848 /* Return the result of sizeof applied to T, a structure for the type
1849 name passed to sizeof (rather than the type itself). */
1852 c_expr_sizeof_type (struct c_type_name *t)
1856 type = groktypename (t);
1857 ret.value = c_sizeof (type);
1858 ret.original_code = ERROR_MARK;
1859 pop_maybe_used (C_TYPE_VARIABLE_SIZE (type));
1863 /* Build a function call to function FUNCTION with parameters PARAMS.
1864 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1865 TREE_VALUE of each node is a parameter-expression.
1866 FUNCTION's data type may be a function type or a pointer-to-function. */
1869 build_function_call (tree function, tree params)
1871 tree fntype, fundecl = 0;
1872 tree coerced_params;
1873 tree name = NULL_TREE, result;
1876 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1877 STRIP_TYPE_NOPS (function);
1879 /* Convert anything with function type to a pointer-to-function. */
1880 if (TREE_CODE (function) == FUNCTION_DECL)
1882 name = DECL_NAME (function);
1884 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1885 (because calling an inline function does not mean the function
1886 needs to be separately compiled). */
1887 fntype = build_type_variant (TREE_TYPE (function),
1888 TREE_READONLY (function),
1889 TREE_THIS_VOLATILE (function));
1891 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1894 function = default_conversion (function);
1896 fntype = TREE_TYPE (function);
1898 if (TREE_CODE (fntype) == ERROR_MARK)
1899 return error_mark_node;
1901 if (!(TREE_CODE (fntype) == POINTER_TYPE
1902 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1904 error ("called object %qE is not a function", function);
1905 return error_mark_node;
1908 if (fundecl && TREE_THIS_VOLATILE (fundecl))
1909 current_function_returns_abnormally = 1;
1911 /* fntype now gets the type of function pointed to. */
1912 fntype = TREE_TYPE (fntype);
1914 /* Check that the function is called through a compatible prototype.
1915 If it is not, replace the call by a trap, wrapped up in a compound
1916 expression if necessary. This has the nice side-effect to prevent
1917 the tree-inliner from generating invalid assignment trees which may
1918 blow up in the RTL expander later.
1920 ??? This doesn't work for Objective-C because objc_comptypes
1921 refuses to compare function prototypes, yet the compiler appears
1922 to build calls that are flagged as invalid by C's comptypes. */
1923 if (!c_dialect_objc ()
1924 && TREE_CODE (function) == NOP_EXPR
1925 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
1926 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
1927 && !comptypes (fntype, TREE_TYPE (tem)))
1929 tree return_type = TREE_TYPE (fntype);
1930 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
1933 /* This situation leads to run-time undefined behavior. We can't,
1934 therefore, simply error unless we can prove that all possible
1935 executions of the program must execute the code. */
1936 warning ("function called through a non-compatible type");
1938 /* We can, however, treat "undefined" any way we please.
1939 Call abort to encourage the user to fix the program. */
1940 inform ("if this code is reached, the program will abort");
1942 if (VOID_TYPE_P (return_type))
1948 if (AGGREGATE_TYPE_P (return_type))
1949 rhs = build_compound_literal (return_type,
1950 build_constructor (return_type,
1953 rhs = fold (build1 (NOP_EXPR, return_type, integer_zero_node));
1955 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
1959 /* Convert the parameters to the types declared in the
1960 function prototype, or apply default promotions. */
1963 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
1965 if (coerced_params == error_mark_node)
1966 return error_mark_node;
1968 /* Check that the arguments to the function are valid. */
1970 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params);
1972 result = build3 (CALL_EXPR, TREE_TYPE (fntype),
1973 function, coerced_params, NULL_TREE);
1974 TREE_SIDE_EFFECTS (result) = 1;
1976 if (require_constant_value)
1978 result = fold_initializer (result);
1980 if (TREE_CONSTANT (result)
1981 && (name == NULL_TREE
1982 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
1983 pedwarn_init ("initializer element is not constant");
1986 result = fold (result);
1988 if (VOID_TYPE_P (TREE_TYPE (result)))
1990 return require_complete_type (result);
1993 /* Convert the argument expressions in the list VALUES
1994 to the types in the list TYPELIST. The result is a list of converted
1995 argument expressions, unless there are too few arguments in which
1996 case it is error_mark_node.
1998 If TYPELIST is exhausted, or when an element has NULL as its type,
1999 perform the default conversions.
2001 PARMLIST is the chain of parm decls for the function being called.
2002 It may be 0, if that info is not available.
2003 It is used only for generating error messages.
2005 FUNCTION is a tree for the called function. It is used only for
2006 error messages, where it is formatted with %qE.
2008 This is also where warnings about wrong number of args are generated.
2010 Both VALUES and the returned value are chains of TREE_LIST nodes
2011 with the elements of the list in the TREE_VALUE slots of those nodes. */
2014 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2016 tree typetail, valtail;
2021 /* Change pointer to function to the function itself for
2023 if (TREE_CODE (function) == ADDR_EXPR
2024 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2025 function = TREE_OPERAND (function, 0);
2027 /* Handle an ObjC selector specially for diagnostics. */
2028 selector = objc_message_selector ();
2030 /* Scan the given expressions and types, producing individual
2031 converted arguments and pushing them on RESULT in reverse order. */
2033 for (valtail = values, typetail = typelist, parmnum = 0;
2035 valtail = TREE_CHAIN (valtail), parmnum++)
2037 tree type = typetail ? TREE_VALUE (typetail) : 0;
2038 tree val = TREE_VALUE (valtail);
2039 tree rname = function;
2040 int argnum = parmnum + 1;
2042 if (type == void_type_node)
2044 error ("too many arguments to function %qE", function);
2048 if (selector && argnum > 2)
2054 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
2055 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
2056 to convert automatically to a pointer. */
2057 if (TREE_CODE (val) == NON_LVALUE_EXPR)
2058 val = TREE_OPERAND (val, 0);
2060 val = default_function_array_conversion (val);
2062 val = require_complete_type (val);
2066 /* Formal parm type is specified by a function prototype. */
2069 if (!COMPLETE_TYPE_P (type))
2071 error ("type of formal parameter %d is incomplete", parmnum + 1);
2076 /* Optionally warn about conversions that
2077 differ from the default conversions. */
2078 if (warn_conversion || warn_traditional)
2080 unsigned int formal_prec = TYPE_PRECISION (type);
2082 if (INTEGRAL_TYPE_P (type)
2083 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2084 warning ("passing argument %d of %qE as integer "
2085 "rather than floating due to prototype",
2087 if (INTEGRAL_TYPE_P (type)
2088 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2089 warning ("passing argument %d of %qE as integer "
2090 "rather than complex due to prototype",
2092 else if (TREE_CODE (type) == COMPLEX_TYPE
2093 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2094 warning ("passing argument %d of %qE as complex "
2095 "rather than floating due to prototype",
2097 else if (TREE_CODE (type) == REAL_TYPE
2098 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2099 warning ("passing argument %d of %qE as floating "
2100 "rather than integer due to prototype",
2102 else if (TREE_CODE (type) == COMPLEX_TYPE
2103 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2104 warning ("passing argument %d of %qE as complex "
2105 "rather than integer due to prototype",
2107 else if (TREE_CODE (type) == REAL_TYPE
2108 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2109 warning ("passing argument %d of %qE as floating "
2110 "rather than complex due to prototype",
2112 /* ??? At some point, messages should be written about
2113 conversions between complex types, but that's too messy
2115 else if (TREE_CODE (type) == REAL_TYPE
2116 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2118 /* Warn if any argument is passed as `float',
2119 since without a prototype it would be `double'. */
2120 if (formal_prec == TYPE_PRECISION (float_type_node))
2121 warning ("passing argument %d of %qE as %<float%> "
2122 "rather than %<double%> due to prototype",
2125 /* Detect integer changing in width or signedness.
2126 These warnings are only activated with
2127 -Wconversion, not with -Wtraditional. */
2128 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2129 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2131 tree would_have_been = default_conversion (val);
2132 tree type1 = TREE_TYPE (would_have_been);
2134 if (TREE_CODE (type) == ENUMERAL_TYPE
2135 && (TYPE_MAIN_VARIANT (type)
2136 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2137 /* No warning if function asks for enum
2138 and the actual arg is that enum type. */
2140 else if (formal_prec != TYPE_PRECISION (type1))
2141 warning ("passing argument %d of %qE with different "
2142 "width due to prototype", argnum, rname);
2143 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2145 /* Don't complain if the formal parameter type
2146 is an enum, because we can't tell now whether
2147 the value was an enum--even the same enum. */
2148 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2150 else if (TREE_CODE (val) == INTEGER_CST
2151 && int_fits_type_p (val, type))
2152 /* Change in signedness doesn't matter
2153 if a constant value is unaffected. */
2155 /* Likewise for a constant in a NOP_EXPR. */
2156 else if (TREE_CODE (val) == NOP_EXPR
2157 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
2158 && int_fits_type_p (TREE_OPERAND (val, 0), type))
2160 /* If the value is extended from a narrower
2161 unsigned type, it doesn't matter whether we
2162 pass it as signed or unsigned; the value
2163 certainly is the same either way. */
2164 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2165 && TYPE_UNSIGNED (TREE_TYPE (val)))
2167 else if (TYPE_UNSIGNED (type))
2168 warning ("passing argument %d of %qE as unsigned "
2169 "due to prototype", argnum, rname);
2171 warning ("passing argument %d of %qE as signed "
2172 "due to prototype", argnum, rname);
2176 parmval = convert_for_assignment (type, val, ic_argpass,
2180 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2181 && INTEGRAL_TYPE_P (type)
2182 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2183 parmval = default_conversion (parmval);
2185 result = tree_cons (NULL_TREE, parmval, result);
2187 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2188 && (TYPE_PRECISION (TREE_TYPE (val))
2189 < TYPE_PRECISION (double_type_node)))
2190 /* Convert `float' to `double'. */
2191 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2193 /* Convert `short' and `char' to full-size `int'. */
2194 result = tree_cons (NULL_TREE, default_conversion (val), result);
2197 typetail = TREE_CHAIN (typetail);
2200 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2202 error ("too few arguments to function %qE", function);
2203 return error_mark_node;
2206 return nreverse (result);
2209 /* This is the entry point used by the parser
2210 for binary operators in the input.
2211 In addition to constructing the expression,
2212 we check for operands that were written with other binary operators
2213 in a way that is likely to confuse the user. */
2216 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2219 struct c_expr result;
2221 enum tree_code code1 = arg1.original_code;
2222 enum tree_code code2 = arg2.original_code;
2224 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2225 result.original_code = code;
2227 if (TREE_CODE (result.value) == ERROR_MARK)
2230 /* Check for cases such as x+y<<z which users are likely
2232 if (warn_parentheses)
2234 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2236 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2237 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2238 warning ("suggest parentheses around + or - inside shift");
2241 if (code == TRUTH_ORIF_EXPR)
2243 if (code1 == TRUTH_ANDIF_EXPR
2244 || code2 == TRUTH_ANDIF_EXPR)
2245 warning ("suggest parentheses around && within ||");
2248 if (code == BIT_IOR_EXPR)
2250 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2251 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2252 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2253 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2254 warning ("suggest parentheses around arithmetic in operand of |");
2255 /* Check cases like x|y==z */
2256 if (TREE_CODE_CLASS (code1) == tcc_comparison
2257 || TREE_CODE_CLASS (code2) == tcc_comparison)
2258 warning ("suggest parentheses around comparison in operand of |");
2261 if (code == BIT_XOR_EXPR)
2263 if (code1 == BIT_AND_EXPR
2264 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2265 || code2 == BIT_AND_EXPR
2266 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2267 warning ("suggest parentheses around arithmetic in operand of ^");
2268 /* Check cases like x^y==z */
2269 if (TREE_CODE_CLASS (code1) == tcc_comparison
2270 || TREE_CODE_CLASS (code2) == tcc_comparison)
2271 warning ("suggest parentheses around comparison in operand of ^");
2274 if (code == BIT_AND_EXPR)
2276 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2277 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2278 warning ("suggest parentheses around + or - in operand of &");
2279 /* Check cases like x&y==z */
2280 if (TREE_CODE_CLASS (code1) == tcc_comparison
2281 || TREE_CODE_CLASS (code2) == tcc_comparison)
2282 warning ("suggest parentheses around comparison in operand of &");
2284 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2285 if (TREE_CODE_CLASS (code) == tcc_comparison
2286 && (TREE_CODE_CLASS (code1) == tcc_comparison
2287 || TREE_CODE_CLASS (code2) == tcc_comparison))
2288 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
2292 unsigned_conversion_warning (result.value, arg1.value);
2293 unsigned_conversion_warning (result.value, arg2.value);
2294 overflow_warning (result.value);
2299 /* Return a tree for the difference of pointers OP0 and OP1.
2300 The resulting tree has type int. */
2303 pointer_diff (tree op0, tree op1)
2305 tree restype = ptrdiff_type_node;
2307 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2308 tree con0, con1, lit0, lit1;
2309 tree orig_op1 = op1;
2311 if (pedantic || warn_pointer_arith)
2313 if (TREE_CODE (target_type) == VOID_TYPE)
2314 pedwarn ("pointer of type %<void *%> used in subtraction");
2315 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2316 pedwarn ("pointer to a function used in subtraction");
2319 /* If the conversion to ptrdiff_type does anything like widening or
2320 converting a partial to an integral mode, we get a convert_expression
2321 that is in the way to do any simplifications.
2322 (fold-const.c doesn't know that the extra bits won't be needed.
2323 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2324 different mode in place.)
2325 So first try to find a common term here 'by hand'; we want to cover
2326 at least the cases that occur in legal static initializers. */
2327 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2328 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2330 if (TREE_CODE (con0) == PLUS_EXPR)
2332 lit0 = TREE_OPERAND (con0, 1);
2333 con0 = TREE_OPERAND (con0, 0);
2336 lit0 = integer_zero_node;
2338 if (TREE_CODE (con1) == PLUS_EXPR)
2340 lit1 = TREE_OPERAND (con1, 1);
2341 con1 = TREE_OPERAND (con1, 0);
2344 lit1 = integer_zero_node;
2346 if (operand_equal_p (con0, con1, 0))
2353 /* First do the subtraction as integers;
2354 then drop through to build the divide operator.
2355 Do not do default conversions on the minus operator
2356 in case restype is a short type. */
2358 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2359 convert (restype, op1), 0);
2360 /* This generates an error if op1 is pointer to incomplete type. */
2361 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2362 error ("arithmetic on pointer to an incomplete type");
2364 /* This generates an error if op0 is pointer to incomplete type. */
2365 op1 = c_size_in_bytes (target_type);
2367 /* Divide by the size, in easiest possible way. */
2368 return fold (build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)));
2371 /* Construct and perhaps optimize a tree representation
2372 for a unary operation. CODE, a tree_code, specifies the operation
2373 and XARG is the operand.
2374 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2375 the default promotions (such as from short to int).
2376 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2377 allows non-lvalues; this is only used to handle conversion of non-lvalue
2378 arrays to pointers in C99. */
2381 build_unary_op (enum tree_code code, tree xarg, int flag)
2383 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2386 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2388 int noconvert = flag;
2390 if (typecode == ERROR_MARK)
2391 return error_mark_node;
2392 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2393 typecode = INTEGER_TYPE;
2398 /* This is used for unary plus, because a CONVERT_EXPR
2399 is enough to prevent anybody from looking inside for
2400 associativity, but won't generate any code. */
2401 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2402 || typecode == COMPLEX_TYPE
2403 || typecode == VECTOR_TYPE))
2405 error ("wrong type argument to unary plus");
2406 return error_mark_node;
2408 else if (!noconvert)
2409 arg = default_conversion (arg);
2410 arg = non_lvalue (arg);
2414 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2415 || typecode == COMPLEX_TYPE
2416 || typecode == VECTOR_TYPE))
2418 error ("wrong type argument to unary minus");
2419 return error_mark_node;
2421 else if (!noconvert)
2422 arg = default_conversion (arg);
2426 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2429 arg = default_conversion (arg);
2431 else if (typecode == COMPLEX_TYPE)
2435 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2437 arg = default_conversion (arg);
2441 error ("wrong type argument to bit-complement");
2442 return error_mark_node;
2447 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2449 error ("wrong type argument to abs");
2450 return error_mark_node;
2452 else if (!noconvert)
2453 arg = default_conversion (arg);
2457 /* Conjugating a real value is a no-op, but allow it anyway. */
2458 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2459 || typecode == COMPLEX_TYPE))
2461 error ("wrong type argument to conjugation");
2462 return error_mark_node;
2464 else if (!noconvert)
2465 arg = default_conversion (arg);
2468 case TRUTH_NOT_EXPR:
2469 if (typecode != INTEGER_TYPE
2470 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2471 && typecode != COMPLEX_TYPE
2472 /* These will convert to a pointer. */
2473 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2475 error ("wrong type argument to unary exclamation mark");
2476 return error_mark_node;
2478 arg = lang_hooks.truthvalue_conversion (arg);
2479 return invert_truthvalue (arg);
2485 if (TREE_CODE (arg) == COMPLEX_CST)
2486 return TREE_REALPART (arg);
2487 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2488 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2493 if (TREE_CODE (arg) == COMPLEX_CST)
2494 return TREE_IMAGPART (arg);
2495 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2496 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2498 return convert (TREE_TYPE (arg), integer_zero_node);
2500 case PREINCREMENT_EXPR:
2501 case POSTINCREMENT_EXPR:
2502 case PREDECREMENT_EXPR:
2503 case POSTDECREMENT_EXPR:
2505 /* Increment or decrement the real part of the value,
2506 and don't change the imaginary part. */
2507 if (typecode == COMPLEX_TYPE)
2512 pedwarn ("ISO C does not support %<++%> and %<--%>"
2513 " on complex types");
2515 arg = stabilize_reference (arg);
2516 real = build_unary_op (REALPART_EXPR, arg, 1);
2517 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2518 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2519 build_unary_op (code, real, 1), imag);
2522 /* Report invalid types. */
2524 if (typecode != POINTER_TYPE
2525 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2527 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2528 error ("wrong type argument to increment");
2530 error ("wrong type argument to decrement");
2532 return error_mark_node;
2537 tree result_type = TREE_TYPE (arg);
2539 arg = get_unwidened (arg, 0);
2540 argtype = TREE_TYPE (arg);
2542 /* Compute the increment. */
2544 if (typecode == POINTER_TYPE)
2546 /* If pointer target is an undefined struct,
2547 we just cannot know how to do the arithmetic. */
2548 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2550 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2551 error ("increment of pointer to unknown structure");
2553 error ("decrement of pointer to unknown structure");
2555 else if ((pedantic || warn_pointer_arith)
2556 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2557 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2559 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2560 pedwarn ("wrong type argument to increment");
2562 pedwarn ("wrong type argument to decrement");
2565 inc = c_size_in_bytes (TREE_TYPE (result_type));
2568 inc = integer_one_node;
2570 inc = convert (argtype, inc);
2572 /* Complain about anything else that is not a true lvalue. */
2573 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2574 || code == POSTINCREMENT_EXPR)
2577 return error_mark_node;
2579 /* Report a read-only lvalue. */
2580 if (TREE_READONLY (arg))
2581 readonly_error (arg,
2582 ((code == PREINCREMENT_EXPR
2583 || code == POSTINCREMENT_EXPR)
2584 ? lv_increment : lv_decrement));
2586 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2587 val = boolean_increment (code, arg);
2589 val = build2 (code, TREE_TYPE (arg), arg, inc);
2590 TREE_SIDE_EFFECTS (val) = 1;
2591 val = convert (result_type, val);
2592 if (TREE_CODE (val) != code)
2593 TREE_NO_WARNING (val) = 1;
2598 /* Note that this operation never does default_conversion. */
2600 /* Let &* cancel out to simplify resulting code. */
2601 if (TREE_CODE (arg) == INDIRECT_REF)
2603 /* Don't let this be an lvalue. */
2604 if (lvalue_p (TREE_OPERAND (arg, 0)))
2605 return non_lvalue (TREE_OPERAND (arg, 0));
2606 return TREE_OPERAND (arg, 0);
2609 /* For &x[y], return x+y */
2610 if (TREE_CODE (arg) == ARRAY_REF)
2612 if (!c_mark_addressable (TREE_OPERAND (arg, 0)))
2613 return error_mark_node;
2614 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2615 TREE_OPERAND (arg, 1), 1);
2618 /* Anything not already handled and not a true memory reference
2619 or a non-lvalue array is an error. */
2620 else if (typecode != FUNCTION_TYPE && !flag
2621 && !lvalue_or_else (arg, lv_addressof))
2622 return error_mark_node;
2624 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2625 argtype = TREE_TYPE (arg);
2627 /* If the lvalue is const or volatile, merge that into the type
2628 to which the address will point. Note that you can't get a
2629 restricted pointer by taking the address of something, so we
2630 only have to deal with `const' and `volatile' here. */
2631 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
2632 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2633 argtype = c_build_type_variant (argtype,
2634 TREE_READONLY (arg),
2635 TREE_THIS_VOLATILE (arg));
2637 if (!c_mark_addressable (arg))
2638 return error_mark_node;
2640 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
2641 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
2643 argtype = build_pointer_type (argtype);
2645 /* ??? Cope with user tricks that amount to offsetof. Delete this
2646 when we have proper support for integer constant expressions. */
2647 val = get_base_address (arg);
2648 if (val && TREE_CODE (val) == INDIRECT_REF
2649 && integer_zerop (TREE_OPERAND (val, 0)))
2650 return fold_convert (argtype, fold_offsetof (arg));
2652 val = build1 (ADDR_EXPR, argtype, arg);
2654 if (TREE_CODE (arg) == COMPOUND_LITERAL_EXPR)
2655 TREE_INVARIANT (val) = TREE_CONSTANT (val) = 1;
2664 argtype = TREE_TYPE (arg);
2665 val = build1 (code, argtype, arg);
2666 return require_constant_value ? fold_initializer (val) : fold (val);
2669 /* Return nonzero if REF is an lvalue valid for this language.
2670 Lvalues can be assigned, unless their type has TYPE_READONLY.
2671 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2676 enum tree_code code = TREE_CODE (ref);
2683 return lvalue_p (TREE_OPERAND (ref, 0));
2685 case COMPOUND_LITERAL_EXPR:
2695 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2696 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2699 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2706 /* Give an error for storing in something that is 'const'. */
2709 readonly_error (tree arg, enum lvalue_use use)
2711 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2712 /* Using this macro rather than (for example) arrays of messages
2713 ensures that all the format strings are checked at compile
2715 #define READONLY_MSG(A, I, D) (use == lv_assign \
2717 : (use == lv_increment ? (I) : (D)))
2718 if (TREE_CODE (arg) == COMPONENT_REF)
2720 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2721 readonly_error (TREE_OPERAND (arg, 0), use);
2723 error (READONLY_MSG (N_("assignment of read-only member %qs"),
2724 N_("increment of read-only member %qs"),
2725 N_("decrement of read-only member %qs")),
2726 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
2728 else if (TREE_CODE (arg) == VAR_DECL)
2729 error (READONLY_MSG (N_("assignment of read-only variable %qs"),
2730 N_("increment of read-only variable %qs"),
2731 N_("decrement of read-only variable %qs")),
2732 IDENTIFIER_POINTER (DECL_NAME (arg)));
2734 error (READONLY_MSG (N_("assignment of read-only location"),
2735 N_("increment of read-only location"),
2736 N_("decrement of read-only location")));
2739 /* Mark EXP saying that we need to be able to take the
2740 address of it; it should not be allocated in a register.
2741 Returns true if successful. */
2744 c_mark_addressable (tree exp)
2749 switch (TREE_CODE (x))
2752 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2755 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2759 /* ... fall through ... */
2765 x = TREE_OPERAND (x, 0);
2768 case COMPOUND_LITERAL_EXPR:
2770 TREE_ADDRESSABLE (x) = 1;
2777 if (C_DECL_REGISTER (x)
2778 && DECL_NONLOCAL (x))
2780 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2783 ("global register variable %qD used in nested function", x);
2786 pedwarn ("register variable %qD used in nested function", x);
2788 else if (C_DECL_REGISTER (x))
2790 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2791 error ("address of global register variable %qD requested", x);
2793 error ("address of register variable %qD requested", x);
2799 TREE_ADDRESSABLE (x) = 1;
2806 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2809 build_conditional_expr (tree ifexp, tree op1, tree op2)
2813 enum tree_code code1;
2814 enum tree_code code2;
2815 tree result_type = NULL;
2816 tree orig_op1 = op1, orig_op2 = op2;
2818 ifexp = lang_hooks.truthvalue_conversion (default_conversion (ifexp));
2820 /* Promote both alternatives. */
2822 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2823 op1 = default_conversion (op1);
2824 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2825 op2 = default_conversion (op2);
2827 if (TREE_CODE (ifexp) == ERROR_MARK
2828 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2829 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2830 return error_mark_node;
2832 type1 = TREE_TYPE (op1);
2833 code1 = TREE_CODE (type1);
2834 type2 = TREE_TYPE (op2);
2835 code2 = TREE_CODE (type2);
2837 /* C90 does not permit non-lvalue arrays in conditional expressions.
2838 In C99 they will be pointers by now. */
2839 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2841 error ("non-lvalue array in conditional expression");
2842 return error_mark_node;
2845 /* Quickly detect the usual case where op1 and op2 have the same type
2847 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
2850 result_type = type1;
2852 result_type = TYPE_MAIN_VARIANT (type1);
2854 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
2855 || code1 == COMPLEX_TYPE)
2856 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
2857 || code2 == COMPLEX_TYPE))
2859 result_type = common_type (type1, type2);
2861 /* If -Wsign-compare, warn here if type1 and type2 have
2862 different signedness. We'll promote the signed to unsigned
2863 and later code won't know it used to be different.
2864 Do this check on the original types, so that explicit casts
2865 will be considered, but default promotions won't. */
2866 if (warn_sign_compare && !skip_evaluation)
2868 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
2869 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
2871 if (unsigned_op1 ^ unsigned_op2)
2873 /* Do not warn if the result type is signed, since the
2874 signed type will only be chosen if it can represent
2875 all the values of the unsigned type. */
2876 if (!TYPE_UNSIGNED (result_type))
2878 /* Do not warn if the signed quantity is an unsuffixed
2879 integer literal (or some static constant expression
2880 involving such literals) and it is non-negative. */
2881 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
2882 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
2885 warning ("signed and unsigned type in conditional expression");
2889 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
2891 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
2892 pedwarn ("ISO C forbids conditional expr with only one void side");
2893 result_type = void_type_node;
2895 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
2897 if (comp_target_types (type1, type2, 1))
2898 result_type = common_pointer_type (type1, type2);
2899 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
2900 && TREE_CODE (orig_op1) != NOP_EXPR)
2901 result_type = qualify_type (type2, type1);
2902 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
2903 && TREE_CODE (orig_op2) != NOP_EXPR)
2904 result_type = qualify_type (type1, type2);
2905 else if (VOID_TYPE_P (TREE_TYPE (type1)))
2907 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
2908 pedwarn ("ISO C forbids conditional expr between "
2909 "%<void *%> and function pointer");
2910 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
2911 TREE_TYPE (type2)));
2913 else if (VOID_TYPE_P (TREE_TYPE (type2)))
2915 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
2916 pedwarn ("ISO C forbids conditional expr between "
2917 "%<void *%> and function pointer");
2918 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
2919 TREE_TYPE (type1)));
2923 pedwarn ("pointer type mismatch in conditional expression");
2924 result_type = build_pointer_type (void_type_node);
2927 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
2929 if (!integer_zerop (op2))
2930 pedwarn ("pointer/integer type mismatch in conditional expression");
2933 op2 = null_pointer_node;
2935 result_type = type1;
2937 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
2939 if (!integer_zerop (op1))
2940 pedwarn ("pointer/integer type mismatch in conditional expression");
2943 op1 = null_pointer_node;
2945 result_type = type2;
2950 if (flag_cond_mismatch)
2951 result_type = void_type_node;
2954 error ("type mismatch in conditional expression");
2955 return error_mark_node;
2959 /* Merge const and volatile flags of the incoming types. */
2961 = build_type_variant (result_type,
2962 TREE_READONLY (op1) || TREE_READONLY (op2),
2963 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
2965 if (result_type != TREE_TYPE (op1))
2966 op1 = convert_and_check (result_type, op1);
2967 if (result_type != TREE_TYPE (op2))
2968 op2 = convert_and_check (result_type, op2);
2970 if (TREE_CODE (ifexp) == INTEGER_CST)
2971 return non_lvalue (integer_zerop (ifexp) ? op2 : op1);
2973 return fold (build3 (COND_EXPR, result_type, ifexp, op1, op2));
2976 /* Return a compound expression that performs two expressions and
2977 returns the value of the second of them. */
2980 build_compound_expr (tree expr1, tree expr2)
2982 /* Convert arrays and functions to pointers. */
2983 expr2 = default_function_array_conversion (expr2);
2985 if (!TREE_SIDE_EFFECTS (expr1))
2987 /* The left-hand operand of a comma expression is like an expression
2988 statement: with -Wextra or -Wunused, we should warn if it doesn't have
2989 any side-effects, unless it was explicitly cast to (void). */
2990 if (warn_unused_value
2991 && !(TREE_CODE (expr1) == CONVERT_EXPR
2992 && VOID_TYPE_P (TREE_TYPE (expr1))))
2993 warning ("left-hand operand of comma expression has no effect");
2996 /* With -Wunused, we should also warn if the left-hand operand does have
2997 side-effects, but computes a value which is not used. For example, in
2998 `foo() + bar(), baz()' the result of the `+' operator is not used,
2999 so we should issue a warning. */
3000 else if (warn_unused_value)
3001 warn_if_unused_value (expr1, input_location);
3003 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3006 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3009 build_c_cast (tree type, tree expr)
3013 if (type == error_mark_node || expr == error_mark_node)
3014 return error_mark_node;
3016 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3017 only in <protocol> qualifications. But when constructing cast expressions,
3018 the protocols do matter and must be kept around. */
3019 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3020 return build1 (NOP_EXPR, type, expr);
3022 type = TYPE_MAIN_VARIANT (type);
3024 if (TREE_CODE (type) == ARRAY_TYPE)
3026 error ("cast specifies array type");
3027 return error_mark_node;
3030 if (TREE_CODE (type) == FUNCTION_TYPE)
3032 error ("cast specifies function type");
3033 return error_mark_node;
3036 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3040 if (TREE_CODE (type) == RECORD_TYPE
3041 || TREE_CODE (type) == UNION_TYPE)
3042 pedwarn ("ISO C forbids casting nonscalar to the same type");
3045 else if (TREE_CODE (type) == UNION_TYPE)
3048 value = default_function_array_conversion (value);
3050 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3051 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3052 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3060 pedwarn ("ISO C forbids casts to union type");
3061 t = digest_init (type,
3062 build_constructor (type,
3063 build_tree_list (field, value)),
3065 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3066 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3069 error ("cast to union type from type not present in union");
3070 return error_mark_node;
3076 /* If casting to void, avoid the error that would come
3077 from default_conversion in the case of a non-lvalue array. */
3078 if (type == void_type_node)
3079 return build1 (CONVERT_EXPR, type, value);
3081 /* Convert functions and arrays to pointers,
3082 but don't convert any other types. */
3083 value = default_function_array_conversion (value);
3084 otype = TREE_TYPE (value);
3086 /* Optionally warn about potentially worrisome casts. */
3089 && TREE_CODE (type) == POINTER_TYPE
3090 && TREE_CODE (otype) == POINTER_TYPE)
3092 tree in_type = type;
3093 tree in_otype = otype;
3097 /* Check that the qualifiers on IN_TYPE are a superset of
3098 the qualifiers of IN_OTYPE. The outermost level of
3099 POINTER_TYPE nodes is uninteresting and we stop as soon
3100 as we hit a non-POINTER_TYPE node on either type. */
3103 in_otype = TREE_TYPE (in_otype);
3104 in_type = TREE_TYPE (in_type);
3106 /* GNU C allows cv-qualified function types. 'const'
3107 means the function is very pure, 'volatile' means it
3108 can't return. We need to warn when such qualifiers
3109 are added, not when they're taken away. */
3110 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3111 && TREE_CODE (in_type) == FUNCTION_TYPE)
3112 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3114 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3116 while (TREE_CODE (in_type) == POINTER_TYPE
3117 && TREE_CODE (in_otype) == POINTER_TYPE);
3120 warning ("cast adds new qualifiers to function type");
3123 /* There are qualifiers present in IN_OTYPE that are not
3124 present in IN_TYPE. */
3125 warning ("cast discards qualifiers from pointer target type");
3128 /* Warn about possible alignment problems. */
3129 if (STRICT_ALIGNMENT && warn_cast_align
3130 && TREE_CODE (type) == POINTER_TYPE
3131 && TREE_CODE (otype) == POINTER_TYPE
3132 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3133 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3134 /* Don't warn about opaque types, where the actual alignment
3135 restriction is unknown. */
3136 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3137 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3138 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3139 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3140 warning ("cast increases required alignment of target type");
3142 if (TREE_CODE (type) == INTEGER_TYPE
3143 && TREE_CODE (otype) == POINTER_TYPE
3144 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3145 && !TREE_CONSTANT (value))
3146 warning ("cast from pointer to integer of different size");
3148 if (warn_bad_function_cast
3149 && TREE_CODE (value) == CALL_EXPR
3150 && TREE_CODE (type) != TREE_CODE (otype))
3151 warning ("cast from function call of type %qT to non-matching "
3152 "type %qT", otype, type);
3154 if (TREE_CODE (type) == POINTER_TYPE
3155 && TREE_CODE (otype) == INTEGER_TYPE
3156 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3157 /* Don't warn about converting any constant. */
3158 && !TREE_CONSTANT (value))
3159 warning ("cast to pointer from integer of different size");
3161 if (TREE_CODE (type) == POINTER_TYPE
3162 && TREE_CODE (otype) == POINTER_TYPE
3163 && TREE_CODE (expr) == ADDR_EXPR
3164 && DECL_P (TREE_OPERAND (expr, 0))
3165 && flag_strict_aliasing && warn_strict_aliasing
3166 && !VOID_TYPE_P (TREE_TYPE (type)))
3168 /* Casting the address of a decl to non void pointer. Warn
3169 if the cast breaks type based aliasing. */
3170 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3171 warning ("type-punning to incomplete type might break strict-aliasing rules");
3174 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3175 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3177 if (!alias_sets_conflict_p (set1, set2))
3178 warning ("dereferencing type-punned pointer will break strict-aliasing rules");
3179 else if (warn_strict_aliasing > 1
3180 && !alias_sets_might_conflict_p (set1, set2))
3181 warning ("dereferencing type-punned pointer might break strict-aliasing rules");
3185 /* If pedantic, warn for conversions between function and object
3186 pointer types, except for converting a null pointer constant
3187 to function pointer type. */
3189 && TREE_CODE (type) == POINTER_TYPE
3190 && TREE_CODE (otype) == POINTER_TYPE
3191 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3192 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3193 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3196 && TREE_CODE (type) == POINTER_TYPE
3197 && TREE_CODE (otype) == POINTER_TYPE
3198 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3199 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3200 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3201 && TREE_CODE (expr) != NOP_EXPR))
3202 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3205 value = convert (type, value);
3207 /* Ignore any integer overflow caused by the cast. */
3208 if (TREE_CODE (value) == INTEGER_CST)
3210 if (EXPR_P (ovalue))
3211 /* If OVALUE had overflow set, then so will VALUE, so it
3212 is safe to overwrite. */
3213 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3215 TREE_OVERFLOW (value) = 0;
3217 if (CONSTANT_CLASS_P (ovalue))
3218 /* Similarly, constant_overflow cannot have become
3220 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3224 /* Don't let a cast be an lvalue. */
3226 value = non_lvalue (value);
3231 /* Interpret a cast of expression EXPR to type TYPE. */
3233 c_cast_expr (struct c_type_name *type_name, tree expr)
3236 int saved_wsp = warn_strict_prototypes;
3238 /* This avoids warnings about unprototyped casts on
3239 integers. E.g. "#define SIG_DFL (void(*)())0". */
3240 if (TREE_CODE (expr) == INTEGER_CST)
3241 warn_strict_prototypes = 0;
3242 type = groktypename (type_name);
3243 warn_strict_prototypes = saved_wsp;
3245 return build_c_cast (type, expr);
3249 /* Build an assignment expression of lvalue LHS from value RHS.
3250 MODIFYCODE is the code for a binary operator that we use
3251 to combine the old value of LHS with RHS to get the new value.
3252 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3255 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3259 tree lhstype = TREE_TYPE (lhs);
3260 tree olhstype = lhstype;
3262 /* Types that aren't fully specified cannot be used in assignments. */
3263 lhs = require_complete_type (lhs);
3265 /* Avoid duplicate error messages from operands that had errors. */
3266 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3267 return error_mark_node;
3269 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3270 /* Do not use STRIP_NOPS here. We do not want an enumerator
3271 whose value is 0 to count as a null pointer constant. */
3272 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3273 rhs = TREE_OPERAND (rhs, 0);
3277 /* If a binary op has been requested, combine the old LHS value with the RHS
3278 producing the value we should actually store into the LHS. */
3280 if (modifycode != NOP_EXPR)
3282 lhs = stabilize_reference (lhs);
3283 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3286 if (!lvalue_or_else (lhs, lv_assign))
3287 return error_mark_node;
3289 /* Give an error for storing in something that is 'const'. */
3291 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3292 || ((TREE_CODE (lhstype) == RECORD_TYPE
3293 || TREE_CODE (lhstype) == UNION_TYPE)
3294 && C_TYPE_FIELDS_READONLY (lhstype)))
3295 readonly_error (lhs, lv_assign);
3297 /* If storing into a structure or union member,
3298 it has probably been given type `int'.
3299 Compute the type that would go with
3300 the actual amount of storage the member occupies. */
3302 if (TREE_CODE (lhs) == COMPONENT_REF
3303 && (TREE_CODE (lhstype) == INTEGER_TYPE
3304 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3305 || TREE_CODE (lhstype) == REAL_TYPE
3306 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3307 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3309 /* If storing in a field that is in actuality a short or narrower than one,
3310 we must store in the field in its actual type. */
3312 if (lhstype != TREE_TYPE (lhs))
3314 lhs = copy_node (lhs);
3315 TREE_TYPE (lhs) = lhstype;
3318 /* Convert new value to destination type. */
3320 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3321 NULL_TREE, NULL_TREE, 0);
3322 if (TREE_CODE (newrhs) == ERROR_MARK)
3323 return error_mark_node;
3325 /* Scan operands. */
3327 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3328 TREE_SIDE_EFFECTS (result) = 1;
3330 /* If we got the LHS in a different type for storing in,
3331 convert the result back to the nominal type of LHS
3332 so that the value we return always has the same type
3333 as the LHS argument. */
3335 if (olhstype == TREE_TYPE (result))
3337 return convert_for_assignment (olhstype, result, ic_assign,
3338 NULL_TREE, NULL_TREE, 0);
3341 /* Convert value RHS to type TYPE as preparation for an assignment
3342 to an lvalue of type TYPE.
3343 The real work of conversion is done by `convert'.
3344 The purpose of this function is to generate error messages
3345 for assignments that are not allowed in C.
3346 ERRTYPE says whether it is argument passing, assignment,
3347 initialization or return.
3349 FUNCTION is a tree for the function being called.
3350 PARMNUM is the number of the argument, for printing in error messages. */
3353 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3354 tree fundecl, tree function, int parmnum)
3356 enum tree_code codel = TREE_CODE (type);
3358 enum tree_code coder;
3359 tree rname = NULL_TREE;
3361 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3364 /* Change pointer to function to the function itself for
3366 if (TREE_CODE (function) == ADDR_EXPR
3367 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3368 function = TREE_OPERAND (function, 0);
3370 /* Handle an ObjC selector specially for diagnostics. */
3371 selector = objc_message_selector ();
3373 if (selector && parmnum > 2)
3380 /* This macro is used to emit diagnostics to ensure that all format
3381 strings are complete sentences, visible to gettext and checked at
3383 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3388 pedwarn (AR, parmnum, rname); \
3390 case ic_argpass_nonproto: \
3391 warning (AR, parmnum, rname); \
3403 gcc_unreachable (); \
3407 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3408 /* Do not use STRIP_NOPS here. We do not want an enumerator
3409 whose value is 0 to count as a null pointer constant. */
3410 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3411 rhs = TREE_OPERAND (rhs, 0);
3413 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3414 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3415 rhs = default_conversion (rhs);
3416 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3417 rhs = decl_constant_value_for_broken_optimization (rhs);
3419 rhstype = TREE_TYPE (rhs);
3420 coder = TREE_CODE (rhstype);
3422 if (coder == ERROR_MARK)
3423 return error_mark_node;
3425 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3427 overflow_warning (rhs);
3428 /* Check for Objective-C protocols. This will automatically
3429 issue a warning if there are protocol violations. No need to
3430 use the return value. */
3431 if (c_dialect_objc ())
3432 objc_comptypes (type, rhstype, 0);
3436 if (coder == VOID_TYPE)
3438 /* Except for passing an argument to an unprototyped function,
3439 this is a constraint violation. When passing an argument to
3440 an unprototyped function, it is compile-time undefined;
3441 making it a constraint in that case was rejected in
3443 error ("void value not ignored as it ought to be");
3444 return error_mark_node;
3446 /* A type converts to a reference to it.
3447 This code doesn't fully support references, it's just for the
3448 special case of va_start and va_copy. */
3449 if (codel == REFERENCE_TYPE
3450 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3452 if (!lvalue_p (rhs))
3454 error ("cannot pass rvalue to reference parameter");
3455 return error_mark_node;
3457 if (!c_mark_addressable (rhs))
3458 return error_mark_node;
3459 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3461 /* We already know that these two types are compatible, but they
3462 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3463 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3464 likely to be va_list, a typedef to __builtin_va_list, which
3465 is different enough that it will cause problems later. */
3466 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3467 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3469 rhs = build1 (NOP_EXPR, type, rhs);
3472 /* Some types can interconvert without explicit casts. */
3473 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3474 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3475 return convert (type, rhs);
3476 /* Arithmetic types all interconvert, and enum is treated like int. */
3477 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3478 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3479 || codel == BOOLEAN_TYPE)
3480 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3481 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3482 || coder == BOOLEAN_TYPE))
3483 return convert_and_check (type, rhs);
3485 /* Conversion to a transparent union from its member types.
3486 This applies only to function arguments. */
3487 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3488 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3491 tree marginal_memb_type = 0;
3493 for (memb_types = TYPE_FIELDS (type); memb_types;
3494 memb_types = TREE_CHAIN (memb_types))
3496 tree memb_type = TREE_TYPE (memb_types);
3498 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3499 TYPE_MAIN_VARIANT (rhstype)))
3502 if (TREE_CODE (memb_type) != POINTER_TYPE)
3505 if (coder == POINTER_TYPE)
3507 tree ttl = TREE_TYPE (memb_type);
3508 tree ttr = TREE_TYPE (rhstype);
3510 /* Any non-function converts to a [const][volatile] void *
3511 and vice versa; otherwise, targets must be the same.
3512 Meanwhile, the lhs target must have all the qualifiers of
3514 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3515 || comp_target_types (memb_type, rhstype, 0))
3517 /* If this type won't generate any warnings, use it. */
3518 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3519 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3520 && TREE_CODE (ttl) == FUNCTION_TYPE)
3521 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3522 == TYPE_QUALS (ttr))
3523 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3524 == TYPE_QUALS (ttl))))
3527 /* Keep looking for a better type, but remember this one. */
3528 if (!marginal_memb_type)
3529 marginal_memb_type = memb_type;
3533 /* Can convert integer zero to any pointer type. */
3534 if (integer_zerop (rhs)
3535 || (TREE_CODE (rhs) == NOP_EXPR
3536 && integer_zerop (TREE_OPERAND (rhs, 0))))
3538 rhs = null_pointer_node;
3543 if (memb_types || marginal_memb_type)
3547 /* We have only a marginally acceptable member type;
3548 it needs a warning. */
3549 tree ttl = TREE_TYPE (marginal_memb_type);
3550 tree ttr = TREE_TYPE (rhstype);
3552 /* Const and volatile mean something different for function
3553 types, so the usual warnings are not appropriate. */
3554 if (TREE_CODE (ttr) == FUNCTION_TYPE
3555 && TREE_CODE (ttl) == FUNCTION_TYPE)
3557 /* Because const and volatile on functions are
3558 restrictions that say the function will not do
3559 certain things, it is okay to use a const or volatile
3560 function where an ordinary one is wanted, but not
3562 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3563 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE "
3564 "makes qualified function "
3565 "pointer from unqualified"),
3566 N_("assignment makes qualified "
3567 "function pointer from "
3569 N_("initialization makes qualified "
3570 "function pointer from "
3572 N_("return makes qualified function "
3573 "pointer from unqualified"));
3575 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3576 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3577 "qualifiers from pointer target type"),
3578 N_("assignment discards qualifiers "
3579 "from pointer target type"),
3580 N_("initialization discards qualifiers "
3581 "from pointer target type"),
3582 N_("return discards qualifiers from "
3583 "pointer target type"));
3586 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3587 pedwarn ("ISO C prohibits argument conversion to union type");
3589 return build1 (NOP_EXPR, type, rhs);
3593 /* Conversions among pointers */
3594 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3595 && (coder == codel))
3597 tree ttl = TREE_TYPE (type);
3598 tree ttr = TREE_TYPE (rhstype);
3599 bool is_opaque_pointer;
3600 int target_cmp = 0; /* Cache comp_target_types () result. */
3602 /* Opaque pointers are treated like void pointers. */
3603 is_opaque_pointer = (targetm.vector_opaque_p (type)
3604 || targetm.vector_opaque_p (rhstype))
3605 && TREE_CODE (ttl) == VECTOR_TYPE
3606 && TREE_CODE (ttr) == VECTOR_TYPE;
3608 /* Any non-function converts to a [const][volatile] void *
3609 and vice versa; otherwise, targets must be the same.
3610 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3611 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3612 || (target_cmp = comp_target_types (type, rhstype, 0))
3613 || is_opaque_pointer
3614 || (c_common_unsigned_type (TYPE_MAIN_VARIANT (ttl))
3615 == c_common_unsigned_type (TYPE_MAIN_VARIANT (ttr))))
3618 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3621 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3622 which are not ANSI null ptr constants. */
3623 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3624 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3625 WARN_FOR_ASSIGNMENT (N_("ISO C forbids passing argument %d of "
3626 "%qE between function pointer "
3628 N_("ISO C forbids assignment between "
3629 "function pointer and %<void *%>"),
3630 N_("ISO C forbids initialization between "
3631 "function pointer and %<void *%>"),
3632 N_("ISO C forbids return between function "
3633 "pointer and %<void *%>"));
3634 /* Const and volatile mean something different for function types,
3635 so the usual warnings are not appropriate. */
3636 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3637 && TREE_CODE (ttl) != FUNCTION_TYPE)
3639 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3640 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3641 "qualifiers from pointer target type"),
3642 N_("assignment discards qualifiers "
3643 "from pointer target type"),
3644 N_("initialization discards qualifiers "
3645 "from pointer target type"),
3646 N_("return discards qualifiers from "
3647 "pointer target type"));
3648 /* If this is not a case of ignoring a mismatch in signedness,
3650 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3653 /* If there is a mismatch, do warn. */
3654 else if (warn_pointer_sign)
3655 WARN_FOR_ASSIGNMENT (N_("pointer targets in passing argument "
3656 "%d of %qE differ in signedness"),
3657 N_("pointer targets in assignment "
3658 "differ in signedness"),
3659 N_("pointer targets in initialization "
3660 "differ in signedness"),
3661 N_("pointer targets in return differ "
3664 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3665 && TREE_CODE (ttr) == FUNCTION_TYPE)
3667 /* Because const and volatile on functions are restrictions
3668 that say the function will not do certain things,
3669 it is okay to use a const or volatile function
3670 where an ordinary one is wanted, but not vice-versa. */
3671 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3672 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3673 "qualified function pointer "
3674 "from unqualified"),
3675 N_("assignment makes qualified function "
3676 "pointer from unqualified"),
3677 N_("initialization makes qualified "
3678 "function pointer from unqualified"),
3679 N_("return makes qualified function "
3680 "pointer from unqualified"));
3684 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE from "
3685 "incompatible pointer type"),
3686 N_("assignment from incompatible pointer type"),
3687 N_("initialization from incompatible "
3689 N_("return from incompatible pointer type"));
3690 return convert (type, rhs);
3692 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3694 /* ??? This should not be an error when inlining calls to
3695 unprototyped functions. */
3696 error ("invalid use of non-lvalue array");
3697 return error_mark_node;
3699 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3701 /* An explicit constant 0 can convert to a pointer,
3702 or one that results from arithmetic, even including
3703 a cast to integer type. */
3704 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3706 !(TREE_CODE (rhs) == NOP_EXPR
3707 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3708 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3709 && integer_zerop (TREE_OPERAND (rhs, 0))))
3710 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3711 "pointer from integer without a cast"),
3712 N_("assignment makes pointer from integer "
3714 N_("initialization makes pointer from "
3715 "integer without a cast"),
3716 N_("return makes pointer from integer "
3719 return convert (type, rhs);
3721 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3723 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes integer "
3724 "from pointer without a cast"),
3725 N_("assignment makes integer from pointer "
3727 N_("initialization makes integer from pointer "
3729 N_("return makes integer from pointer "
3731 return convert (type, rhs);
3733 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3734 return convert (type, rhs);
3739 case ic_argpass_nonproto:
3740 /* ??? This should not be an error when inlining calls to
3741 unprototyped functions. */
3742 error ("incompatible type for argument %d of %qE", parmnum, rname);
3745 error ("incompatible types in assignment");
3748 error ("incompatible types in initialization");
3751 error ("incompatible types in return");
3757 return error_mark_node;
3760 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3761 is used for error and waring reporting and indicates which argument
3762 is being processed. */
3765 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3769 /* If FN was prototyped, the value has been converted already
3770 in convert_arguments. */
3771 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3774 type = TREE_TYPE (parm);
3775 ret = convert_for_assignment (type, value,
3776 ic_argpass_nonproto, fn,
3778 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3779 && INTEGRAL_TYPE_P (type)
3780 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3781 ret = default_conversion (ret);
3785 /* If VALUE is a compound expr all of whose expressions are constant, then
3786 return its value. Otherwise, return error_mark_node.
3788 This is for handling COMPOUND_EXPRs as initializer elements
3789 which is allowed with a warning when -pedantic is specified. */
3792 valid_compound_expr_initializer (tree value, tree endtype)
3794 if (TREE_CODE (value) == COMPOUND_EXPR)
3796 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3798 return error_mark_node;
3799 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3802 else if (!initializer_constant_valid_p (value, endtype))
3803 return error_mark_node;
3808 /* Perform appropriate conversions on the initial value of a variable,
3809 store it in the declaration DECL,
3810 and print any error messages that are appropriate.
3811 If the init is invalid, store an ERROR_MARK. */
3814 store_init_value (tree decl, tree init)
3818 /* If variable's type was invalidly declared, just ignore it. */
3820 type = TREE_TYPE (decl);
3821 if (TREE_CODE (type) == ERROR_MARK)
3824 /* Digest the specified initializer into an expression. */
3826 value = digest_init (type, init, true, TREE_STATIC (decl));
3828 /* Store the expression if valid; else report error. */
3830 if (warn_traditional && !in_system_header
3831 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
3832 warning ("traditional C rejects automatic aggregate initialization");
3834 DECL_INITIAL (decl) = value;
3836 /* ANSI wants warnings about out-of-range constant initializers. */
3837 STRIP_TYPE_NOPS (value);
3838 constant_expression_warning (value);
3840 /* Check if we need to set array size from compound literal size. */
3841 if (TREE_CODE (type) == ARRAY_TYPE
3842 && TYPE_DOMAIN (type) == 0
3843 && value != error_mark_node)
3845 tree inside_init = init;
3847 if (TREE_CODE (init) == NON_LVALUE_EXPR)
3848 inside_init = TREE_OPERAND (init, 0);
3849 inside_init = fold (inside_init);
3851 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
3853 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
3855 if (TYPE_DOMAIN (TREE_TYPE (decl)))
3857 /* For int foo[] = (int [3]){1}; we need to set array size
3858 now since later on array initializer will be just the
3859 brace enclosed list of the compound literal. */
3860 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
3862 layout_decl (decl, 0);
3868 /* Methods for storing and printing names for error messages. */
3870 /* Implement a spelling stack that allows components of a name to be pushed
3871 and popped. Each element on the stack is this structure. */
3883 #define SPELLING_STRING 1
3884 #define SPELLING_MEMBER 2
3885 #define SPELLING_BOUNDS 3
3887 static struct spelling *spelling; /* Next stack element (unused). */
3888 static struct spelling *spelling_base; /* Spelling stack base. */
3889 static int spelling_size; /* Size of the spelling stack. */
3891 /* Macros to save and restore the spelling stack around push_... functions.
3892 Alternative to SAVE_SPELLING_STACK. */
3894 #define SPELLING_DEPTH() (spelling - spelling_base)
3895 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
3897 /* Push an element on the spelling stack with type KIND and assign VALUE
3900 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
3902 int depth = SPELLING_DEPTH (); \
3904 if (depth >= spelling_size) \
3906 spelling_size += 10; \
3907 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
3909 RESTORE_SPELLING_DEPTH (depth); \
3912 spelling->kind = (KIND); \
3913 spelling->MEMBER = (VALUE); \
3917 /* Push STRING on the stack. Printed literally. */
3920 push_string (const char *string)
3922 PUSH_SPELLING (SPELLING_STRING, string, u.s);
3925 /* Push a member name on the stack. Printed as '.' STRING. */
3928 push_member_name (tree decl)
3930 const char *const string
3931 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
3932 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
3935 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
3938 push_array_bounds (int bounds)
3940 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
3943 /* Compute the maximum size in bytes of the printed spelling. */
3946 spelling_length (void)
3951 for (p = spelling_base; p < spelling; p++)
3953 if (p->kind == SPELLING_BOUNDS)
3956 size += strlen (p->u.s) + 1;
3962 /* Print the spelling to BUFFER and return it. */
3965 print_spelling (char *buffer)
3970 for (p = spelling_base; p < spelling; p++)
3971 if (p->kind == SPELLING_BOUNDS)
3973 sprintf (d, "[%d]", p->u.i);
3979 if (p->kind == SPELLING_MEMBER)
3981 for (s = p->u.s; (*d = *s++); d++)
3988 /* Issue an error message for a bad initializer component.
3989 MSGID identifies the message.
3990 The component name is taken from the spelling stack. */
3993 error_init (const char *msgid)
3997 error ("%s", _(msgid));
3998 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4000 error ("(near initialization for %qs)", ofwhat);
4003 /* Issue a pedantic warning for a bad initializer component.
4004 MSGID identifies the message.
4005 The component name is taken from the spelling stack. */
4008 pedwarn_init (const char *msgid)
4012 pedwarn ("%s", _(msgid));
4013 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4015 pedwarn ("(near initialization for %qs)", ofwhat);
4018 /* Issue a warning for a bad initializer component.
4019 MSGID identifies the message.
4020 The component name is taken from the spelling stack. */
4023 warning_init (const char *msgid)
4027 warning ("%s", _(msgid));
4028 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4030 warning ("(near initialization for %qs)", ofwhat);
4033 /* If TYPE is an array type and EXPR is a parenthesized string
4034 constant, warn if pedantic that EXPR is being used to initialize an
4035 object of type TYPE. */
4038 maybe_warn_string_init (tree type, struct c_expr expr)
4041 && TREE_CODE (type) == ARRAY_TYPE
4042 && TREE_CODE (expr.value) == STRING_CST
4043 && expr.original_code != STRING_CST)
4044 pedwarn_init ("array initialized from parenthesized string constant");
4047 /* Digest the parser output INIT as an initializer for type TYPE.
4048 Return a C expression of type TYPE to represent the initial value.
4050 If INIT is a string constant, STRICT_STRING is true if it is
4051 unparenthesized or we should not warn here for it being parenthesized.
4052 For other types of INIT, STRICT_STRING is not used.
4054 REQUIRE_CONSTANT requests an error if non-constant initializers or
4055 elements are seen. */
4058 digest_init (tree type, tree init, bool strict_string, int require_constant)
4060 enum tree_code code = TREE_CODE (type);
4061 tree inside_init = init;
4063 if (type == error_mark_node
4064 || init == error_mark_node
4065 || TREE_TYPE (init) == error_mark_node)
4066 return error_mark_node;
4068 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4069 /* Do not use STRIP_NOPS here. We do not want an enumerator
4070 whose value is 0 to count as a null pointer constant. */
4071 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4072 inside_init = TREE_OPERAND (init, 0);
4074 inside_init = fold (inside_init);
4076 /* Initialization of an array of chars from a string constant
4077 optionally enclosed in braces. */
4079 if (code == ARRAY_TYPE && inside_init
4080 && TREE_CODE (inside_init) == STRING_CST)
4082 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4083 /* Note that an array could be both an array of character type
4084 and an array of wchar_t if wchar_t is signed char or unsigned
4086 bool char_array = (typ1 == char_type_node
4087 || typ1 == signed_char_type_node
4088 || typ1 == unsigned_char_type_node);
4089 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4090 if (char_array || wchar_array)
4094 expr.value = inside_init;
4095 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4096 maybe_warn_string_init (type, expr);
4099 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4102 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4103 TYPE_MAIN_VARIANT (type)))
4106 if (!wchar_array && !char_string)
4108 error_init ("char-array initialized from wide string");
4109 return error_mark_node;
4111 if (char_string && !char_array)
4113 error_init ("wchar_t-array initialized from non-wide string");
4114 return error_mark_node;
4117 TREE_TYPE (inside_init) = type;
4118 if (TYPE_DOMAIN (type) != 0
4119 && TYPE_SIZE (type) != 0
4120 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4121 /* Subtract 1 (or sizeof (wchar_t))
4122 because it's ok to ignore the terminating null char
4123 that is counted in the length of the constant. */
4124 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4125 TREE_STRING_LENGTH (inside_init)
4126 - ((TYPE_PRECISION (typ1)
4127 != TYPE_PRECISION (char_type_node))
4128 ? (TYPE_PRECISION (wchar_type_node)
4131 pedwarn_init ("initializer-string for array of chars is too long");
4135 else if (INTEGRAL_TYPE_P (typ1))
4137 error_init ("array of inappropriate type initialized "
4138 "from string constant");
4139 return error_mark_node;
4143 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4144 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4145 below and handle as a constructor. */
4146 if (code == VECTOR_TYPE
4147 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4148 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4149 && TREE_CONSTANT (inside_init))
4151 if (TREE_CODE (inside_init) == VECTOR_CST
4152 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4153 TYPE_MAIN_VARIANT (type)))
4156 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4159 /* Any type can be initialized
4160 from an expression of the same type, optionally with braces. */
4162 if (inside_init && TREE_TYPE (inside_init) != 0
4163 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4164 TYPE_MAIN_VARIANT (type))
4165 || (code == ARRAY_TYPE
4166 && comptypes (TREE_TYPE (inside_init), type))
4167 || (code == VECTOR_TYPE
4168 && comptypes (TREE_TYPE (inside_init), type))
4169 || (code == POINTER_TYPE
4170 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4171 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4173 || (code == POINTER_TYPE
4174 && TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE
4175 && comptypes (TREE_TYPE (inside_init),
4176 TREE_TYPE (type)))))
4178 if (code == POINTER_TYPE)
4180 inside_init = default_function_array_conversion (inside_init);
4182 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4184 error_init ("invalid use of non-lvalue array");
4185 return error_mark_node;
4189 if (code == VECTOR_TYPE)
4190 /* Although the types are compatible, we may require a
4192 inside_init = convert (type, inside_init);
4194 if (require_constant && !flag_isoc99
4195 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4197 /* As an extension, allow initializing objects with static storage
4198 duration with compound literals (which are then treated just as
4199 the brace enclosed list they contain). */
4200 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4201 inside_init = DECL_INITIAL (decl);
4204 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4205 && TREE_CODE (inside_init) != CONSTRUCTOR)
4207 error_init ("array initialized from non-constant array expression");
4208 return error_mark_node;
4211 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4212 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4214 /* Compound expressions can only occur here if -pedantic or
4215 -pedantic-errors is specified. In the later case, we always want
4216 an error. In the former case, we simply want a warning. */
4217 if (require_constant && pedantic
4218 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4221 = valid_compound_expr_initializer (inside_init,
4222 TREE_TYPE (inside_init));
4223 if (inside_init == error_mark_node)
4224 error_init ("initializer element is not constant");
4226 pedwarn_init ("initializer element is not constant");
4227 if (flag_pedantic_errors)
4228 inside_init = error_mark_node;
4230 else if (require_constant
4231 && !initializer_constant_valid_p (inside_init,
4232 TREE_TYPE (inside_init)))
4234 error_init ("initializer element is not constant");
4235 inside_init = error_mark_node;
4241 /* Handle scalar types, including conversions. */
4243 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4244 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4245 || code == VECTOR_TYPE)
4247 /* Note that convert_for_assignment calls default_conversion
4248 for arrays and functions. We must not call it in the
4249 case where inside_init is a null pointer constant. */
4251 = convert_for_assignment (type, init, ic_init,
4252 NULL_TREE, NULL_TREE, 0);
4254 /* Check to see if we have already given an error message. */
4255 if (inside_init == error_mark_node)
4257 else if (require_constant && !TREE_CONSTANT (inside_init))
4259 error_init ("initializer element is not constant");
4260 inside_init = error_mark_node;
4262 else if (require_constant
4263 && !initializer_constant_valid_p (inside_init,
4264 TREE_TYPE (inside_init)))
4266 error_init ("initializer element is not computable at load time");
4267 inside_init = error_mark_node;
4273 /* Come here only for records and arrays. */
4275 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4277 error_init ("variable-sized object may not be initialized");
4278 return error_mark_node;
4281 error_init ("invalid initializer");
4282 return error_mark_node;
4285 /* Handle initializers that use braces. */
4287 /* Type of object we are accumulating a constructor for.
4288 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4289 static tree constructor_type;
4291 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4293 static tree constructor_fields;
4295 /* For an ARRAY_TYPE, this is the specified index
4296 at which to store the next element we get. */
4297 static tree constructor_index;
4299 /* For an ARRAY_TYPE, this is the maximum index. */
4300 static tree constructor_max_index;
4302 /* For a RECORD_TYPE, this is the first field not yet written out. */
4303 static tree constructor_unfilled_fields;
4305 /* For an ARRAY_TYPE, this is the index of the first element
4306 not yet written out. */
4307 static tree constructor_unfilled_index;
4309 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4310 This is so we can generate gaps between fields, when appropriate. */
4311 static tree constructor_bit_index;
4313 /* If we are saving up the elements rather than allocating them,
4314 this is the list of elements so far (in reverse order,
4315 most recent first). */
4316 static tree constructor_elements;
4318 /* 1 if constructor should be incrementally stored into a constructor chain,
4319 0 if all the elements should be kept in AVL tree. */
4320 static int constructor_incremental;
4322 /* 1 if so far this constructor's elements are all compile-time constants. */
4323 static int constructor_constant;
4325 /* 1 if so far this constructor's elements are all valid address constants. */
4326 static int constructor_simple;
4328 /* 1 if this constructor is erroneous so far. */
4329 static int constructor_erroneous;
4331 /* Structure for managing pending initializer elements, organized as an
4336 struct init_node *left, *right;
4337 struct init_node *parent;
4343 /* Tree of pending elements at this constructor level.
4344 These are elements encountered out of order
4345 which belong at places we haven't reached yet in actually
4347 Will never hold tree nodes across GC runs. */
4348 static struct init_node *constructor_pending_elts;
4350 /* The SPELLING_DEPTH of this constructor. */
4351 static int constructor_depth;
4353 /* DECL node for which an initializer is being read.
4354 0 means we are reading a constructor expression
4355 such as (struct foo) {...}. */
4356 static tree constructor_decl;
4358 /* Nonzero if this is an initializer for a top-level decl. */
4359 static int constructor_top_level;
4361 /* Nonzero if there were any member designators in this initializer. */
4362 static int constructor_designated;
4364 /* Nesting depth of designator list. */
4365 static int designator_depth;
4367 /* Nonzero if there were diagnosed errors in this designator list. */
4368 static int designator_errorneous;
4371 /* This stack has a level for each implicit or explicit level of
4372 structuring in the initializer, including the outermost one. It
4373 saves the values of most of the variables above. */
4375 struct constructor_range_stack;
4377 struct constructor_stack
4379 struct constructor_stack *next;
4384 tree unfilled_index;
4385 tree unfilled_fields;
4388 struct init_node *pending_elts;
4391 /* If value nonzero, this value should replace the entire
4392 constructor at this level. */
4393 struct c_expr replacement_value;
4394 struct constructor_range_stack *range_stack;
4404 struct constructor_stack *constructor_stack;
4406 /* This stack represents designators from some range designator up to
4407 the last designator in the list. */
4409 struct constructor_range_stack
4411 struct constructor_range_stack *next, *prev;
4412 struct constructor_stack *stack;
4419 struct constructor_range_stack *constructor_range_stack;
4421 /* This stack records separate initializers that are nested.
4422 Nested initializers can't happen in ANSI C, but GNU C allows them
4423 in cases like { ... (struct foo) { ... } ... }. */
4425 struct initializer_stack
4427 struct initializer_stack *next;
4429 struct constructor_stack *constructor_stack;
4430 struct constructor_range_stack *constructor_range_stack;
4432 struct spelling *spelling;
4433 struct spelling *spelling_base;
4436 char require_constant_value;
4437 char require_constant_elements;
4440 struct initializer_stack *initializer_stack;
4442 /* Prepare to parse and output the initializer for variable DECL. */
4445 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4448 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4450 p->decl = constructor_decl;
4451 p->require_constant_value = require_constant_value;
4452 p->require_constant_elements = require_constant_elements;
4453 p->constructor_stack = constructor_stack;
4454 p->constructor_range_stack = constructor_range_stack;
4455 p->elements = constructor_elements;
4456 p->spelling = spelling;
4457 p->spelling_base = spelling_base;
4458 p->spelling_size = spelling_size;
4459 p->top_level = constructor_top_level;
4460 p->next = initializer_stack;
4461 initializer_stack = p;
4463 constructor_decl = decl;
4464 constructor_designated = 0;
4465 constructor_top_level = top_level;
4467 if (decl != 0 && decl != error_mark_node)
4469 require_constant_value = TREE_STATIC (decl);
4470 require_constant_elements
4471 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4472 /* For a scalar, you can always use any value to initialize,
4473 even within braces. */
4474 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4475 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4476 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4477 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4478 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4482 require_constant_value = 0;
4483 require_constant_elements = 0;
4484 locus = "(anonymous)";
4487 constructor_stack = 0;
4488 constructor_range_stack = 0;
4490 missing_braces_mentioned = 0;
4494 RESTORE_SPELLING_DEPTH (0);
4497 push_string (locus);
4503 struct initializer_stack *p = initializer_stack;
4505 /* Free the whole constructor stack of this initializer. */
4506 while (constructor_stack)
4508 struct constructor_stack *q = constructor_stack;
4509 constructor_stack = q->next;
4513 gcc_assert (!constructor_range_stack);
4515 /* Pop back to the data of the outer initializer (if any). */
4516 free (spelling_base);
4518 constructor_decl = p->decl;
4519 require_constant_value = p->require_constant_value;
4520 require_constant_elements = p->require_constant_elements;
4521 constructor_stack = p->constructor_stack;
4522 constructor_range_stack = p->constructor_range_stack;
4523 constructor_elements = p->elements;
4524 spelling = p->spelling;
4525 spelling_base = p->spelling_base;
4526 spelling_size = p->spelling_size;
4527 constructor_top_level = p->top_level;
4528 initializer_stack = p->next;
4532 /* Call here when we see the initializer is surrounded by braces.
4533 This is instead of a call to push_init_level;
4534 it is matched by a call to pop_init_level.
4536 TYPE is the type to initialize, for a constructor expression.
4537 For an initializer for a decl, TYPE is zero. */
4540 really_start_incremental_init (tree type)
4542 struct constructor_stack *p = XNEW (struct constructor_stack);
4545 type = TREE_TYPE (constructor_decl);
4547 if (targetm.vector_opaque_p (type))
4548 error ("opaque vector types cannot be initialized");
4550 p->type = constructor_type;
4551 p->fields = constructor_fields;
4552 p->index = constructor_index;
4553 p->max_index = constructor_max_index;
4554 p->unfilled_index = constructor_unfilled_index;
4555 p->unfilled_fields = constructor_unfilled_fields;
4556 p->bit_index = constructor_bit_index;
4557 p->elements = constructor_elements;
4558 p->constant = constructor_constant;
4559 p->simple = constructor_simple;
4560 p->erroneous = constructor_erroneous;
4561 p->pending_elts = constructor_pending_elts;
4562 p->depth = constructor_depth;
4563 p->replacement_value.value = 0;
4564 p->replacement_value.original_code = ERROR_MARK;
4568 p->incremental = constructor_incremental;
4569 p->designated = constructor_designated;
4571 constructor_stack = p;
4573 constructor_constant = 1;
4574 constructor_simple = 1;
4575 constructor_depth = SPELLING_DEPTH ();
4576 constructor_elements = 0;
4577 constructor_pending_elts = 0;
4578 constructor_type = type;
4579 constructor_incremental = 1;
4580 constructor_designated = 0;
4581 designator_depth = 0;
4582 designator_errorneous = 0;
4584 if (TREE_CODE (constructor_type) == RECORD_TYPE
4585 || TREE_CODE (constructor_type) == UNION_TYPE)
4587 constructor_fields = TYPE_FIELDS (constructor_type);
4588 /* Skip any nameless bit fields at the beginning. */
4589 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4590 && DECL_NAME (constructor_fields) == 0)
4591 constructor_fields = TREE_CHAIN (constructor_fields);
4593 constructor_unfilled_fields = constructor_fields;
4594 constructor_bit_index = bitsize_zero_node;
4596 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4598 if (TYPE_DOMAIN (constructor_type))
4600 constructor_max_index
4601 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4603 /* Detect non-empty initializations of zero-length arrays. */
4604 if (constructor_max_index == NULL_TREE
4605 && TYPE_SIZE (constructor_type))
4606 constructor_max_index = build_int_cst (NULL_TREE, -1);
4608 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4609 to initialize VLAs will cause a proper error; avoid tree
4610 checking errors as well by setting a safe value. */
4611 if (constructor_max_index
4612 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4613 constructor_max_index = build_int_cst (NULL_TREE, -1);
4616 = convert (bitsizetype,
4617 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4620 constructor_index = bitsize_zero_node;
4622 constructor_unfilled_index = constructor_index;
4624 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4626 /* Vectors are like simple fixed-size arrays. */
4627 constructor_max_index =
4628 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4629 constructor_index = convert (bitsizetype, bitsize_zero_node);
4630 constructor_unfilled_index = constructor_index;
4634 /* Handle the case of int x = {5}; */
4635 constructor_fields = constructor_type;
4636 constructor_unfilled_fields = constructor_type;
4640 /* Push down into a subobject, for initialization.
4641 If this is for an explicit set of braces, IMPLICIT is 0.
4642 If it is because the next element belongs at a lower level,
4643 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4646 push_init_level (int implicit)
4648 struct constructor_stack *p;
4649 tree value = NULL_TREE;
4651 /* If we've exhausted any levels that didn't have braces,
4653 while (constructor_stack->implicit)
4655 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4656 || TREE_CODE (constructor_type) == UNION_TYPE)
4657 && constructor_fields == 0)
4658 process_init_element (pop_init_level (1));
4659 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4660 && constructor_max_index
4661 && tree_int_cst_lt (constructor_max_index, constructor_index))
4662 process_init_element (pop_init_level (1));
4667 /* Unless this is an explicit brace, we need to preserve previous
4671 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4672 || TREE_CODE (constructor_type) == UNION_TYPE)
4673 && constructor_fields)
4674 value = find_init_member (constructor_fields);
4675 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4676 value = find_init_member (constructor_index);
4679 p = XNEW (struct constructor_stack);
4680 p->type = constructor_type;
4681 p->fields = constructor_fields;
4682 p->index = constructor_index;
4683 p->max_index = constructor_max_index;
4684 p->unfilled_index = constructor_unfilled_index;
4685 p->unfilled_fields = constructor_unfilled_fields;
4686 p->bit_index = constructor_bit_index;
4687 p->elements = constructor_elements;
4688 p->constant = constructor_constant;
4689 p->simple = constructor_simple;
4690 p->erroneous = constructor_erroneous;
4691 p->pending_elts = constructor_pending_elts;
4692 p->depth = constructor_depth;
4693 p->replacement_value.value = 0;
4694 p->replacement_value.original_code = ERROR_MARK;
4695 p->implicit = implicit;
4697 p->incremental = constructor_incremental;
4698 p->designated = constructor_designated;
4699 p->next = constructor_stack;
4701 constructor_stack = p;
4703 constructor_constant = 1;
4704 constructor_simple = 1;
4705 constructor_depth = SPELLING_DEPTH ();
4706 constructor_elements = 0;
4707 constructor_incremental = 1;
4708 constructor_designated = 0;
4709 constructor_pending_elts = 0;
4712 p->range_stack = constructor_range_stack;
4713 constructor_range_stack = 0;
4714 designator_depth = 0;
4715 designator_errorneous = 0;
4718 /* Don't die if an entire brace-pair level is superfluous
4719 in the containing level. */
4720 if (constructor_type == 0)
4722 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4723 || TREE_CODE (constructor_type) == UNION_TYPE)
4725 /* Don't die if there are extra init elts at the end. */
4726 if (constructor_fields == 0)
4727 constructor_type = 0;
4730 constructor_type = TREE_TYPE (constructor_fields);
4731 push_member_name (constructor_fields);
4732 constructor_depth++;
4735 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4737 constructor_type = TREE_TYPE (constructor_type);
4738 push_array_bounds (tree_low_cst (constructor_index, 0));
4739 constructor_depth++;
4742 if (constructor_type == 0)
4744 error_init ("extra brace group at end of initializer");
4745 constructor_fields = 0;
4746 constructor_unfilled_fields = 0;
4750 if (value && TREE_CODE (value) == CONSTRUCTOR)
4752 constructor_constant = TREE_CONSTANT (value);
4753 constructor_simple = TREE_STATIC (value);
4754 constructor_elements = CONSTRUCTOR_ELTS (value);
4755 if (constructor_elements
4756 && (TREE_CODE (constructor_type) == RECORD_TYPE
4757 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4758 set_nonincremental_init ();
4761 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4763 missing_braces_mentioned = 1;
4764 warning_init ("missing braces around initializer");
4767 if (TREE_CODE (constructor_type) == RECORD_TYPE
4768 || TREE_CODE (constructor_type) == UNION_TYPE)
4770 constructor_fields = TYPE_FIELDS (constructor_type);
4771 /* Skip any nameless bit fields at the beginning. */
4772 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4773 && DECL_NAME (constructor_fields) == 0)
4774 constructor_fields = TREE_CHAIN (constructor_fields);
4776 constructor_unfilled_fields = constructor_fields;
4777 constructor_bit_index = bitsize_zero_node;
4779 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4781 /* Vectors are like simple fixed-size arrays. */
4782 constructor_max_index =
4783 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4784 constructor_index = convert (bitsizetype, integer_zero_node);
4785 constructor_unfilled_index = constructor_index;
4787 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4789 if (TYPE_DOMAIN (constructor_type))
4791 constructor_max_index
4792 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4794 /* Detect non-empty initializations of zero-length arrays. */
4795 if (constructor_max_index == NULL_TREE
4796 && TYPE_SIZE (constructor_type))
4797 constructor_max_index = build_int_cst (NULL_TREE, -1);
4799 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4800 to initialize VLAs will cause a proper error; avoid tree
4801 checking errors as well by setting a safe value. */
4802 if (constructor_max_index
4803 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4804 constructor_max_index = build_int_cst (NULL_TREE, -1);
4807 = convert (bitsizetype,
4808 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4811 constructor_index = bitsize_zero_node;
4813 constructor_unfilled_index = constructor_index;
4814 if (value && TREE_CODE (value) == STRING_CST)
4816 /* We need to split the char/wchar array into individual
4817 characters, so that we don't have to special case it
4819 set_nonincremental_init_from_string (value);
4824 warning_init ("braces around scalar initializer");
4825 constructor_fields = constructor_type;
4826 constructor_unfilled_fields = constructor_type;
4830 /* At the end of an implicit or explicit brace level,
4831 finish up that level of constructor. If a single expression
4832 with redundant braces initialized that level, return the
4833 c_expr structure for that expression. Otherwise, the original_code
4834 element is set to ERROR_MARK.
4835 If we were outputting the elements as they are read, return 0 as the value
4836 from inner levels (process_init_element ignores that),
4837 but return error_mark_node as the value from the outermost level
4838 (that's what we want to put in DECL_INITIAL).
4839 Otherwise, return a CONSTRUCTOR expression as the value. */
4842 pop_init_level (int implicit)
4844 struct constructor_stack *p;
4847 ret.original_code = ERROR_MARK;
4851 /* When we come to an explicit close brace,
4852 pop any inner levels that didn't have explicit braces. */
4853 while (constructor_stack->implicit)
4854 process_init_element (pop_init_level (1));
4856 gcc_assert (!constructor_range_stack);
4859 /* Now output all pending elements. */
4860 constructor_incremental = 1;
4861 output_pending_init_elements (1);
4863 p = constructor_stack;
4865 /* Error for initializing a flexible array member, or a zero-length
4866 array member in an inappropriate context. */
4867 if (constructor_type && constructor_fields
4868 && TREE_CODE (constructor_type) == ARRAY_TYPE
4869 && TYPE_DOMAIN (constructor_type)
4870 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
4872 /* Silently discard empty initializations. The parser will
4873 already have pedwarned for empty brackets. */
4874 if (integer_zerop (constructor_unfilled_index))
4875 constructor_type = NULL_TREE;
4878 gcc_assert (!TYPE_SIZE (constructor_type));
4880 if (constructor_depth > 2)
4881 error_init ("initialization of flexible array member in a nested context");
4883 pedwarn_init ("initialization of a flexible array member");
4885 /* We have already issued an error message for the existence
4886 of a flexible array member not at the end of the structure.
4887 Discard the initializer so that we do not abort later. */
4888 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
4889 constructor_type = NULL_TREE;
4893 /* Warn when some struct elements are implicitly initialized to zero. */
4894 if (warn_missing_field_initializers
4896 && TREE_CODE (constructor_type) == RECORD_TYPE
4897 && constructor_unfilled_fields)
4899 /* Do not warn for flexible array members or zero-length arrays. */
4900 while (constructor_unfilled_fields
4901 && (!DECL_SIZE (constructor_unfilled_fields)
4902 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
4903 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
4905 /* Do not warn if this level of the initializer uses member
4906 designators; it is likely to be deliberate. */
4907 if (constructor_unfilled_fields && !constructor_designated)
4909 push_member_name (constructor_unfilled_fields);
4910 warning_init ("missing initializer");
4911 RESTORE_SPELLING_DEPTH (constructor_depth);
4915 /* Pad out the end of the structure. */
4916 if (p->replacement_value.value)
4917 /* If this closes a superfluous brace pair,
4918 just pass out the element between them. */
4919 ret = p->replacement_value;
4920 else if (constructor_type == 0)
4922 else if (TREE_CODE (constructor_type) != RECORD_TYPE
4923 && TREE_CODE (constructor_type) != UNION_TYPE
4924 && TREE_CODE (constructor_type) != ARRAY_TYPE
4925 && TREE_CODE (constructor_type) != VECTOR_TYPE)
4927 /* A nonincremental scalar initializer--just return
4928 the element, after verifying there is just one. */
4929 if (constructor_elements == 0)
4931 if (!constructor_erroneous)
4932 error_init ("empty scalar initializer");
4933 ret.value = error_mark_node;
4935 else if (TREE_CHAIN (constructor_elements) != 0)
4937 error_init ("extra elements in scalar initializer");
4938 ret.value = TREE_VALUE (constructor_elements);
4941 ret.value = TREE_VALUE (constructor_elements);
4945 if (constructor_erroneous)
4946 ret.value = error_mark_node;
4949 ret.value = build_constructor (constructor_type,
4950 nreverse (constructor_elements));
4951 if (constructor_constant)
4952 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
4953 if (constructor_constant && constructor_simple)
4954 TREE_STATIC (ret.value) = 1;
4958 constructor_type = p->type;
4959 constructor_fields = p->fields;
4960 constructor_index = p->index;
4961 constructor_max_index = p->max_index;
4962 constructor_unfilled_index = p->unfilled_index;
4963 constructor_unfilled_fields = p->unfilled_fields;
4964 constructor_bit_index = p->bit_index;
4965 constructor_elements = p->elements;
4966 constructor_constant = p->constant;
4967 constructor_simple = p->simple;
4968 constructor_erroneous = p->erroneous;
4969 constructor_incremental = p->incremental;
4970 constructor_designated = p->designated;
4971 constructor_pending_elts = p->pending_elts;
4972 constructor_depth = p->depth;
4974 constructor_range_stack = p->range_stack;
4975 RESTORE_SPELLING_DEPTH (constructor_depth);
4977 constructor_stack = p->next;
4982 if (constructor_stack == 0)
4984 ret.value = error_mark_node;
4992 /* Common handling for both array range and field name designators.
4993 ARRAY argument is nonzero for array ranges. Returns zero for success. */
4996 set_designator (int array)
4999 enum tree_code subcode;
5001 /* Don't die if an entire brace-pair level is superfluous
5002 in the containing level. */
5003 if (constructor_type == 0)
5006 /* If there were errors in this designator list already, bail out
5008 if (designator_errorneous)
5011 if (!designator_depth)
5013 gcc_assert (!constructor_range_stack);
5015 /* Designator list starts at the level of closest explicit
5017 while (constructor_stack->implicit)
5018 process_init_element (pop_init_level (1));
5019 constructor_designated = 1;
5023 switch (TREE_CODE (constructor_type))
5027 subtype = TREE_TYPE (constructor_fields);
5028 if (subtype != error_mark_node)
5029 subtype = TYPE_MAIN_VARIANT (subtype);
5032 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5038 subcode = TREE_CODE (subtype);
5039 if (array && subcode != ARRAY_TYPE)
5041 error_init ("array index in non-array initializer");
5044 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5046 error_init ("field name not in record or union initializer");
5050 constructor_designated = 1;
5051 push_init_level (2);
5055 /* If there are range designators in designator list, push a new designator
5056 to constructor_range_stack. RANGE_END is end of such stack range or
5057 NULL_TREE if there is no range designator at this level. */
5060 push_range_stack (tree range_end)
5062 struct constructor_range_stack *p;
5064 p = GGC_NEW (struct constructor_range_stack);
5065 p->prev = constructor_range_stack;
5067 p->fields = constructor_fields;
5068 p->range_start = constructor_index;
5069 p->index = constructor_index;
5070 p->stack = constructor_stack;
5071 p->range_end = range_end;
5072 if (constructor_range_stack)
5073 constructor_range_stack->next = p;
5074 constructor_range_stack = p;
5077 /* Within an array initializer, specify the next index to be initialized.
5078 FIRST is that index. If LAST is nonzero, then initialize a range
5079 of indices, running from FIRST through LAST. */
5082 set_init_index (tree first, tree last)
5084 if (set_designator (1))
5087 designator_errorneous = 1;
5089 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5090 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5092 error_init ("array index in initializer not of integer type");
5096 while ((TREE_CODE (first) == NOP_EXPR
5097 || TREE_CODE (first) == CONVERT_EXPR
5098 || TREE_CODE (first) == NON_LVALUE_EXPR)
5099 && (TYPE_MODE (TREE_TYPE (first))
5100 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5101 first = TREE_OPERAND (first, 0);
5104 while ((TREE_CODE (last) == NOP_EXPR
5105 || TREE_CODE (last) == CONVERT_EXPR
5106 || TREE_CODE (last) == NON_LVALUE_EXPR)
5107 && (TYPE_MODE (TREE_TYPE (last))
5108 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5109 last = TREE_OPERAND (last, 0);
5111 if (TREE_CODE (first) != INTEGER_CST)
5112 error_init ("nonconstant array index in initializer");
5113 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5114 error_init ("nonconstant array index in initializer");
5115 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5116 error_init ("array index in non-array initializer");
5117 else if (tree_int_cst_sgn (first) == -1)
5118 error_init ("array index in initializer exceeds array bounds");
5119 else if (constructor_max_index
5120 && tree_int_cst_lt (constructor_max_index, first))
5121 error_init ("array index in initializer exceeds array bounds");
5124 constructor_index = convert (bitsizetype, first);
5128 if (tree_int_cst_equal (first, last))
5130 else if (tree_int_cst_lt (last, first))
5132 error_init ("empty index range in initializer");
5137 last = convert (bitsizetype, last);
5138 if (constructor_max_index != 0
5139 && tree_int_cst_lt (constructor_max_index, last))
5141 error_init ("array index range in initializer exceeds array bounds");
5148 designator_errorneous = 0;
5149 if (constructor_range_stack || last)
5150 push_range_stack (last);
5154 /* Within a struct initializer, specify the next field to be initialized. */
5157 set_init_label (tree fieldname)
5161 if (set_designator (0))
5164 designator_errorneous = 1;
5166 if (TREE_CODE (constructor_type) != RECORD_TYPE
5167 && TREE_CODE (constructor_type) != UNION_TYPE)
5169 error_init ("field name not in record or union initializer");
5173 for (tail = TYPE_FIELDS (constructor_type); tail;
5174 tail = TREE_CHAIN (tail))
5176 if (DECL_NAME (tail) == fieldname)
5181 error ("unknown field %qs specified in initializer",
5182 IDENTIFIER_POINTER (fieldname));
5185 constructor_fields = tail;
5187 designator_errorneous = 0;
5188 if (constructor_range_stack)
5189 push_range_stack (NULL_TREE);
5193 /* Add a new initializer to the tree of pending initializers. PURPOSE
5194 identifies the initializer, either array index or field in a structure.
5195 VALUE is the value of that index or field. */
5198 add_pending_init (tree purpose, tree value)
5200 struct init_node *p, **q, *r;
5202 q = &constructor_pending_elts;
5205 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5210 if (tree_int_cst_lt (purpose, p->purpose))
5212 else if (tree_int_cst_lt (p->purpose, purpose))
5216 if (TREE_SIDE_EFFECTS (p->value))
5217 warning_init ("initialized field with side-effects overwritten");
5227 bitpos = bit_position (purpose);
5231 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5233 else if (p->purpose != purpose)
5237 if (TREE_SIDE_EFFECTS (p->value))
5238 warning_init ("initialized field with side-effects overwritten");
5245 r = GGC_NEW (struct init_node);
5246 r->purpose = purpose;
5257 struct init_node *s;
5261 if (p->balance == 0)
5263 else if (p->balance < 0)
5270 p->left->parent = p;
5287 constructor_pending_elts = r;
5292 struct init_node *t = r->right;
5296 r->right->parent = r;
5301 p->left->parent = p;
5304 p->balance = t->balance < 0;
5305 r->balance = -(t->balance > 0);
5320 constructor_pending_elts = t;
5326 /* p->balance == +1; growth of left side balances the node. */
5331 else /* r == p->right */
5333 if (p->balance == 0)
5334 /* Growth propagation from right side. */
5336 else if (p->balance > 0)
5343 p->right->parent = p;
5360 constructor_pending_elts = r;
5362 else /* r->balance == -1 */
5365 struct init_node *t = r->left;
5369 r->left->parent = r;
5374 p->right->parent = p;
5377 r->balance = (t->balance < 0);
5378 p->balance = -(t->balance > 0);
5393 constructor_pending_elts = t;
5399 /* p->balance == -1; growth of right side balances the node. */
5410 /* Build AVL tree from a sorted chain. */
5413 set_nonincremental_init (void)
5417 if (TREE_CODE (constructor_type) != RECORD_TYPE
5418 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5421 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5422 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5423 constructor_elements = 0;
5424 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5426 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5427 /* Skip any nameless bit fields at the beginning. */
5428 while (constructor_unfilled_fields != 0
5429 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5430 && DECL_NAME (constructor_unfilled_fields) == 0)
5431 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5434 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5436 if (TYPE_DOMAIN (constructor_type))
5437 constructor_unfilled_index
5438 = convert (bitsizetype,
5439 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5441 constructor_unfilled_index = bitsize_zero_node;
5443 constructor_incremental = 0;
5446 /* Build AVL tree from a string constant. */
5449 set_nonincremental_init_from_string (tree str)
5451 tree value, purpose, type;
5452 HOST_WIDE_INT val[2];
5453 const char *p, *end;
5454 int byte, wchar_bytes, charwidth, bitpos;
5456 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5458 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5459 == TYPE_PRECISION (char_type_node))
5463 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5464 == TYPE_PRECISION (wchar_type_node));
5465 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5467 charwidth = TYPE_PRECISION (char_type_node);
5468 type = TREE_TYPE (constructor_type);
5469 p = TREE_STRING_POINTER (str);
5470 end = p + TREE_STRING_LENGTH (str);
5472 for (purpose = bitsize_zero_node;
5473 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5474 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5476 if (wchar_bytes == 1)
5478 val[1] = (unsigned char) *p++;
5485 for (byte = 0; byte < wchar_bytes; byte++)
5487 if (BYTES_BIG_ENDIAN)
5488 bitpos = (wchar_bytes - byte - 1) * charwidth;
5490 bitpos = byte * charwidth;
5491 val[bitpos < HOST_BITS_PER_WIDE_INT]
5492 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5493 << (bitpos % HOST_BITS_PER_WIDE_INT);
5497 if (!TYPE_UNSIGNED (type))
5499 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5500 if (bitpos < HOST_BITS_PER_WIDE_INT)
5502 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5504 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5508 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5513 else if (val[0] & (((HOST_WIDE_INT) 1)
5514 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5515 val[0] |= ((HOST_WIDE_INT) -1)
5516 << (bitpos - HOST_BITS_PER_WIDE_INT);
5519 value = build_int_cst_wide (type, val[1], val[0]);
5520 add_pending_init (purpose, value);
5523 constructor_incremental = 0;
5526 /* Return value of FIELD in pending initializer or zero if the field was
5527 not initialized yet. */
5530 find_init_member (tree field)
5532 struct init_node *p;
5534 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5536 if (constructor_incremental
5537 && tree_int_cst_lt (field, constructor_unfilled_index))
5538 set_nonincremental_init ();
5540 p = constructor_pending_elts;
5543 if (tree_int_cst_lt (field, p->purpose))
5545 else if (tree_int_cst_lt (p->purpose, field))
5551 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5553 tree bitpos = bit_position (field);
5555 if (constructor_incremental
5556 && (!constructor_unfilled_fields
5557 || tree_int_cst_lt (bitpos,
5558 bit_position (constructor_unfilled_fields))))
5559 set_nonincremental_init ();
5561 p = constructor_pending_elts;
5564 if (field == p->purpose)
5566 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5572 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5574 if (constructor_elements
5575 && TREE_PURPOSE (constructor_elements) == field)
5576 return TREE_VALUE (constructor_elements);
5581 /* "Output" the next constructor element.
5582 At top level, really output it to assembler code now.
5583 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5584 TYPE is the data type that the containing data type wants here.
5585 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5586 If VALUE is a string constant, STRICT_STRING is true if it is
5587 unparenthesized or we should not warn here for it being parenthesized.
5588 For other types of VALUE, STRICT_STRING is not used.
5590 PENDING if non-nil means output pending elements that belong
5591 right after this element. (PENDING is normally 1;
5592 it is 0 while outputting pending elements, to avoid recursion.) */
5595 output_init_element (tree value, bool strict_string, tree type, tree field,
5598 if (type == error_mark_node || value == error_mark_node)
5600 constructor_erroneous = 1;
5603 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5604 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5605 && !(TREE_CODE (value) == STRING_CST
5606 && TREE_CODE (type) == ARRAY_TYPE
5607 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5608 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5609 TYPE_MAIN_VARIANT (type))))
5610 value = default_conversion (value);
5612 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5613 && require_constant_value && !flag_isoc99 && pending)
5615 /* As an extension, allow initializing objects with static storage
5616 duration with compound literals (which are then treated just as
5617 the brace enclosed list they contain). */
5618 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5619 value = DECL_INITIAL (decl);
5622 if (value == error_mark_node)
5623 constructor_erroneous = 1;
5624 else if (!TREE_CONSTANT (value))
5625 constructor_constant = 0;
5626 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5627 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5628 || TREE_CODE (constructor_type) == UNION_TYPE)
5629 && DECL_C_BIT_FIELD (field)
5630 && TREE_CODE (value) != INTEGER_CST))
5631 constructor_simple = 0;
5633 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5635 if (require_constant_value)
5637 error_init ("initializer element is not constant");
5638 value = error_mark_node;
5640 else if (require_constant_elements)
5641 pedwarn ("initializer element is not computable at load time");
5644 /* If this field is empty (and not at the end of structure),
5645 don't do anything other than checking the initializer. */
5647 && (TREE_TYPE (field) == error_mark_node
5648 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5649 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5650 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5651 || TREE_CHAIN (field)))))
5654 value = digest_init (type, value, strict_string, require_constant_value);
5655 if (value == error_mark_node)
5657 constructor_erroneous = 1;
5661 /* If this element doesn't come next in sequence,
5662 put it on constructor_pending_elts. */
5663 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5664 && (!constructor_incremental
5665 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5667 if (constructor_incremental
5668 && tree_int_cst_lt (field, constructor_unfilled_index))
5669 set_nonincremental_init ();
5671 add_pending_init (field, value);
5674 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5675 && (!constructor_incremental
5676 || field != constructor_unfilled_fields))
5678 /* We do this for records but not for unions. In a union,
5679 no matter which field is specified, it can be initialized
5680 right away since it starts at the beginning of the union. */
5681 if (constructor_incremental)
5683 if (!constructor_unfilled_fields)
5684 set_nonincremental_init ();
5687 tree bitpos, unfillpos;
5689 bitpos = bit_position (field);
5690 unfillpos = bit_position (constructor_unfilled_fields);
5692 if (tree_int_cst_lt (bitpos, unfillpos))
5693 set_nonincremental_init ();
5697 add_pending_init (field, value);
5700 else if (TREE_CODE (constructor_type) == UNION_TYPE
5701 && constructor_elements)
5703 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5704 warning_init ("initialized field with side-effects overwritten");
5706 /* We can have just one union field set. */
5707 constructor_elements = 0;
5710 /* Otherwise, output this element either to
5711 constructor_elements or to the assembler file. */
5713 if (field && TREE_CODE (field) == INTEGER_CST)
5714 field = copy_node (field);
5715 constructor_elements
5716 = tree_cons (field, value, constructor_elements);
5718 /* Advance the variable that indicates sequential elements output. */
5719 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5720 constructor_unfilled_index
5721 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5723 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5725 constructor_unfilled_fields
5726 = TREE_CHAIN (constructor_unfilled_fields);
5728 /* Skip any nameless bit fields. */
5729 while (constructor_unfilled_fields != 0
5730 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5731 && DECL_NAME (constructor_unfilled_fields) == 0)
5732 constructor_unfilled_fields =
5733 TREE_CHAIN (constructor_unfilled_fields);
5735 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5736 constructor_unfilled_fields = 0;
5738 /* Now output any pending elements which have become next. */
5740 output_pending_init_elements (0);
5743 /* Output any pending elements which have become next.
5744 As we output elements, constructor_unfilled_{fields,index}
5745 advances, which may cause other elements to become next;
5746 if so, they too are output.
5748 If ALL is 0, we return when there are
5749 no more pending elements to output now.
5751 If ALL is 1, we output space as necessary so that
5752 we can output all the pending elements. */
5755 output_pending_init_elements (int all)
5757 struct init_node *elt = constructor_pending_elts;
5762 /* Look through the whole pending tree.
5763 If we find an element that should be output now,
5764 output it. Otherwise, set NEXT to the element
5765 that comes first among those still pending. */
5770 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5772 if (tree_int_cst_equal (elt->purpose,
5773 constructor_unfilled_index))
5774 output_init_element (elt->value, true,
5775 TREE_TYPE (constructor_type),
5776 constructor_unfilled_index, 0);
5777 else if (tree_int_cst_lt (constructor_unfilled_index,
5780 /* Advance to the next smaller node. */
5785 /* We have reached the smallest node bigger than the
5786 current unfilled index. Fill the space first. */
5787 next = elt->purpose;
5793 /* Advance to the next bigger node. */
5798 /* We have reached the biggest node in a subtree. Find
5799 the parent of it, which is the next bigger node. */
5800 while (elt->parent && elt->parent->right == elt)
5803 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5806 next = elt->purpose;
5812 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5813 || TREE_CODE (constructor_type) == UNION_TYPE)
5815 tree ctor_unfilled_bitpos, elt_bitpos;
5817 /* If the current record is complete we are done. */
5818 if (constructor_unfilled_fields == 0)
5821 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
5822 elt_bitpos = bit_position (elt->purpose);
5823 /* We can't compare fields here because there might be empty
5824 fields in between. */
5825 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
5827 constructor_unfilled_fields = elt->purpose;
5828 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
5831 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
5833 /* Advance to the next smaller node. */
5838 /* We have reached the smallest node bigger than the
5839 current unfilled field. Fill the space first. */
5840 next = elt->purpose;
5846 /* Advance to the next bigger node. */
5851 /* We have reached the biggest node in a subtree. Find
5852 the parent of it, which is the next bigger node. */
5853 while (elt->parent && elt->parent->right == elt)
5857 && (tree_int_cst_lt (ctor_unfilled_bitpos,
5858 bit_position (elt->purpose))))
5860 next = elt->purpose;
5868 /* Ordinarily return, but not if we want to output all
5869 and there are elements left. */
5870 if (!(all && next != 0))
5873 /* If it's not incremental, just skip over the gap, so that after
5874 jumping to retry we will output the next successive element. */
5875 if (TREE_CODE (constructor_type) == RECORD_TYPE
5876 || TREE_CODE (constructor_type) == UNION_TYPE)
5877 constructor_unfilled_fields = next;
5878 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5879 constructor_unfilled_index = next;
5881 /* ELT now points to the node in the pending tree with the next
5882 initializer to output. */
5886 /* Add one non-braced element to the current constructor level.
5887 This adjusts the current position within the constructor's type.
5888 This may also start or terminate implicit levels
5889 to handle a partly-braced initializer.
5891 Once this has found the correct level for the new element,
5892 it calls output_init_element. */
5895 process_init_element (struct c_expr value)
5897 tree orig_value = value.value;
5898 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
5899 bool strict_string = value.original_code == STRING_CST;
5901 designator_depth = 0;
5902 designator_errorneous = 0;
5904 /* Handle superfluous braces around string cst as in
5905 char x[] = {"foo"}; */
5908 && TREE_CODE (constructor_type) == ARRAY_TYPE
5909 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
5910 && integer_zerop (constructor_unfilled_index))
5912 if (constructor_stack->replacement_value.value)
5913 error_init ("excess elements in char array initializer");
5914 constructor_stack->replacement_value = value;
5918 if (constructor_stack->replacement_value.value != 0)
5920 error_init ("excess elements in struct initializer");
5924 /* Ignore elements of a brace group if it is entirely superfluous
5925 and has already been diagnosed. */
5926 if (constructor_type == 0)
5929 /* If we've exhausted any levels that didn't have braces,
5931 while (constructor_stack->implicit)
5933 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5934 || TREE_CODE (constructor_type) == UNION_TYPE)
5935 && constructor_fields == 0)
5936 process_init_element (pop_init_level (1));
5937 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5938 && (constructor_max_index == 0
5939 || tree_int_cst_lt (constructor_max_index,
5940 constructor_index)))
5941 process_init_element (pop_init_level (1));
5946 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
5947 if (constructor_range_stack)
5949 /* If value is a compound literal and we'll be just using its
5950 content, don't put it into a SAVE_EXPR. */
5951 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
5952 || !require_constant_value
5954 value.value = save_expr (value.value);
5959 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5962 enum tree_code fieldcode;
5964 if (constructor_fields == 0)
5966 pedwarn_init ("excess elements in struct initializer");
5970 fieldtype = TREE_TYPE (constructor_fields);
5971 if (fieldtype != error_mark_node)
5972 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
5973 fieldcode = TREE_CODE (fieldtype);
5975 /* Error for non-static initialization of a flexible array member. */
5976 if (fieldcode == ARRAY_TYPE
5977 && !require_constant_value
5978 && TYPE_SIZE (fieldtype) == NULL_TREE
5979 && TREE_CHAIN (constructor_fields) == NULL_TREE)
5981 error_init ("non-static initialization of a flexible array member");
5985 /* Accept a string constant to initialize a subarray. */
5986 if (value.value != 0
5987 && fieldcode == ARRAY_TYPE
5988 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
5990 value.value = orig_value;
5991 /* Otherwise, if we have come to a subaggregate,
5992 and we don't have an element of its type, push into it. */
5993 else if (value.value != 0
5994 && value.value != error_mark_node
5995 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
5996 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
5997 || fieldcode == UNION_TYPE))
5999 push_init_level (1);
6005 push_member_name (constructor_fields);
6006 output_init_element (value.value, strict_string,
6007 fieldtype, constructor_fields, 1);
6008 RESTORE_SPELLING_DEPTH (constructor_depth);
6011 /* Do the bookkeeping for an element that was
6012 directly output as a constructor. */
6014 /* For a record, keep track of end position of last field. */
6015 if (DECL_SIZE (constructor_fields))
6016 constructor_bit_index
6017 = size_binop (PLUS_EXPR,
6018 bit_position (constructor_fields),
6019 DECL_SIZE (constructor_fields));
6021 /* If the current field was the first one not yet written out,
6022 it isn't now, so update. */
6023 if (constructor_unfilled_fields == constructor_fields)
6025 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6026 /* Skip any nameless bit fields. */
6027 while (constructor_unfilled_fields != 0
6028 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6029 && DECL_NAME (constructor_unfilled_fields) == 0)
6030 constructor_unfilled_fields =
6031 TREE_CHAIN (constructor_unfilled_fields);
6035 constructor_fields = TREE_CHAIN (constructor_fields);
6036 /* Skip any nameless bit fields at the beginning. */
6037 while (constructor_fields != 0
6038 && DECL_C_BIT_FIELD (constructor_fields)
6039 && DECL_NAME (constructor_fields) == 0)
6040 constructor_fields = TREE_CHAIN (constructor_fields);
6042 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6045 enum tree_code fieldcode;
6047 if (constructor_fields == 0)
6049 pedwarn_init ("excess elements in union initializer");
6053 fieldtype = TREE_TYPE (constructor_fields);
6054 if (fieldtype != error_mark_node)
6055 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6056 fieldcode = TREE_CODE (fieldtype);
6058 /* Warn that traditional C rejects initialization of unions.
6059 We skip the warning if the value is zero. This is done
6060 under the assumption that the zero initializer in user
6061 code appears conditioned on e.g. __STDC__ to avoid
6062 "missing initializer" warnings and relies on default
6063 initialization to zero in the traditional C case.
6064 We also skip the warning if the initializer is designated,
6065 again on the assumption that this must be conditional on
6066 __STDC__ anyway (and we've already complained about the
6067 member-designator already). */
6068 if (warn_traditional && !in_system_header && !constructor_designated
6069 && !(value.value && (integer_zerop (value.value)
6070 || real_zerop (value.value))))
6071 warning ("traditional C rejects initialization of unions");
6073 /* Accept a string constant to initialize a subarray. */
6074 if (value.value != 0
6075 && fieldcode == ARRAY_TYPE
6076 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6078 value.value = orig_value;
6079 /* Otherwise, if we have come to a subaggregate,
6080 and we don't have an element of its type, push into it. */
6081 else if (value.value != 0
6082 && value.value != error_mark_node
6083 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6084 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6085 || fieldcode == UNION_TYPE))
6087 push_init_level (1);
6093 push_member_name (constructor_fields);
6094 output_init_element (value.value, strict_string,
6095 fieldtype, constructor_fields, 1);
6096 RESTORE_SPELLING_DEPTH (constructor_depth);
6099 /* Do the bookkeeping for an element that was
6100 directly output as a constructor. */
6102 constructor_bit_index = DECL_SIZE (constructor_fields);
6103 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6106 constructor_fields = 0;
6108 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6110 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6111 enum tree_code eltcode = TREE_CODE (elttype);
6113 /* Accept a string constant to initialize a subarray. */
6114 if (value.value != 0
6115 && eltcode == ARRAY_TYPE
6116 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6118 value.value = orig_value;
6119 /* Otherwise, if we have come to a subaggregate,
6120 and we don't have an element of its type, push into it. */
6121 else if (value.value != 0
6122 && value.value != error_mark_node
6123 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6124 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6125 || eltcode == UNION_TYPE))
6127 push_init_level (1);
6131 if (constructor_max_index != 0
6132 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6133 || integer_all_onesp (constructor_max_index)))
6135 pedwarn_init ("excess elements in array initializer");
6139 /* Now output the actual element. */
6142 push_array_bounds (tree_low_cst (constructor_index, 0));
6143 output_init_element (value.value, strict_string,
6144 elttype, constructor_index, 1);
6145 RESTORE_SPELLING_DEPTH (constructor_depth);
6149 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6152 /* If we are doing the bookkeeping for an element that was
6153 directly output as a constructor, we must update
6154 constructor_unfilled_index. */
6155 constructor_unfilled_index = constructor_index;
6157 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6159 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6161 /* Do a basic check of initializer size. Note that vectors
6162 always have a fixed size derived from their type. */
6163 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6165 pedwarn_init ("excess elements in vector initializer");
6169 /* Now output the actual element. */
6171 output_init_element (value.value, strict_string,
6172 elttype, constructor_index, 1);
6175 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6178 /* If we are doing the bookkeeping for an element that was
6179 directly output as a constructor, we must update
6180 constructor_unfilled_index. */
6181 constructor_unfilled_index = constructor_index;
6184 /* Handle the sole element allowed in a braced initializer
6185 for a scalar variable. */
6186 else if (constructor_fields == 0)
6188 pedwarn_init ("excess elements in scalar initializer");
6194 output_init_element (value.value, strict_string,
6195 constructor_type, NULL_TREE, 1);
6196 constructor_fields = 0;
6199 /* Handle range initializers either at this level or anywhere higher
6200 in the designator stack. */
6201 if (constructor_range_stack)
6203 struct constructor_range_stack *p, *range_stack;
6206 range_stack = constructor_range_stack;
6207 constructor_range_stack = 0;
6208 while (constructor_stack != range_stack->stack)
6210 gcc_assert (constructor_stack->implicit);
6211 process_init_element (pop_init_level (1));
6213 for (p = range_stack;
6214 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6217 gcc_assert (constructor_stack->implicit);
6218 process_init_element (pop_init_level (1));
6221 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6222 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6227 constructor_index = p->index;
6228 constructor_fields = p->fields;
6229 if (finish && p->range_end && p->index == p->range_start)
6237 push_init_level (2);
6238 p->stack = constructor_stack;
6239 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6240 p->index = p->range_start;
6244 constructor_range_stack = range_stack;
6251 constructor_range_stack = 0;
6254 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6255 (guaranteed to be 'volatile' or null) and ARGS (represented using
6256 an ASM_EXPR node). */
6258 build_asm_stmt (tree cv_qualifier, tree args)
6260 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6261 ASM_VOLATILE_P (args) = 1;
6262 return add_stmt (args);
6265 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6266 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6267 SIMPLE indicates whether there was anything at all after the
6268 string in the asm expression -- asm("blah") and asm("blah" : )
6269 are subtly different. We use a ASM_EXPR node to represent this. */
6271 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6277 const char *constraint;
6278 const char **oconstraints;
6279 bool allows_mem, allows_reg, is_inout;
6280 int ninputs, noutputs;
6282 ninputs = list_length (inputs);
6283 noutputs = list_length (outputs);
6284 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6286 string = resolve_asm_operand_names (string, outputs, inputs);
6288 /* Remove output conversions that change the type but not the mode. */
6289 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6291 tree output = TREE_VALUE (tail);
6293 /* ??? Really, this should not be here. Users should be using a
6294 proper lvalue, dammit. But there's a long history of using casts
6295 in the output operands. In cases like longlong.h, this becomes a
6296 primitive form of typechecking -- if the cast can be removed, then
6297 the output operand had a type of the proper width; otherwise we'll
6298 get an error. Gross, but ... */
6299 STRIP_NOPS (output);
6301 if (!lvalue_or_else (output, lv_asm))
6302 output = error_mark_node;
6304 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6305 oconstraints[i] = constraint;
6307 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6308 &allows_mem, &allows_reg, &is_inout))
6310 /* If the operand is going to end up in memory,
6311 mark it addressable. */
6312 if (!allows_reg && !c_mark_addressable (output))
6313 output = error_mark_node;
6316 output = error_mark_node;
6318 TREE_VALUE (tail) = output;
6321 /* Perform default conversions on array and function inputs.
6322 Don't do this for other types as it would screw up operands
6323 expected to be in memory. */
6324 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6328 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6329 input = TREE_VALUE (tail);
6331 input = default_function_array_conversion (input);
6333 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6334 oconstraints, &allows_mem, &allows_reg))
6336 /* If the operand is going to end up in memory,
6337 mark it addressable. */
6338 if (!allows_reg && allows_mem)
6340 /* Strip the nops as we allow this case. FIXME, this really
6341 should be rejected or made deprecated. */
6343 if (!c_mark_addressable (input))
6344 input = error_mark_node;
6348 input = error_mark_node;
6350 TREE_VALUE (tail) = input;
6353 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6355 /* Simple asm statements are treated as volatile. */
6358 ASM_VOLATILE_P (args) = 1;
6359 ASM_INPUT_P (args) = 1;
6365 /* Generate a goto statement to LABEL. */
6368 c_finish_goto_label (tree label)
6370 tree decl = lookup_label (label);
6374 TREE_USED (decl) = 1;
6375 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6378 /* Generate a computed goto statement to EXPR. */
6381 c_finish_goto_ptr (tree expr)
6384 pedwarn ("ISO C forbids %<goto *expr;%>");
6385 expr = convert (ptr_type_node, expr);
6386 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6389 /* Generate a C `return' statement. RETVAL is the expression for what
6390 to return, or a null pointer for `return;' with no value. */
6393 c_finish_return (tree retval)
6395 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6397 if (TREE_THIS_VOLATILE (current_function_decl))
6398 warning ("function declared %<noreturn%> has a %<return%> statement");
6402 current_function_returns_null = 1;
6403 if ((warn_return_type || flag_isoc99)
6404 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6405 pedwarn_c99 ("%<return%> with no value, in "
6406 "function returning non-void");
6408 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6410 current_function_returns_null = 1;
6411 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6412 pedwarn ("%<return%> with a value, in function returning void");
6416 tree t = convert_for_assignment (valtype, retval, ic_return,
6417 NULL_TREE, NULL_TREE, 0);
6418 tree res = DECL_RESULT (current_function_decl);
6421 current_function_returns_value = 1;
6422 if (t == error_mark_node)
6425 inner = t = convert (TREE_TYPE (res), t);
6427 /* Strip any conversions, additions, and subtractions, and see if
6428 we are returning the address of a local variable. Warn if so. */
6431 switch (TREE_CODE (inner))
6433 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6435 inner = TREE_OPERAND (inner, 0);
6439 /* If the second operand of the MINUS_EXPR has a pointer
6440 type (or is converted from it), this may be valid, so
6441 don't give a warning. */
6443 tree op1 = TREE_OPERAND (inner, 1);
6445 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6446 && (TREE_CODE (op1) == NOP_EXPR
6447 || TREE_CODE (op1) == NON_LVALUE_EXPR
6448 || TREE_CODE (op1) == CONVERT_EXPR))
6449 op1 = TREE_OPERAND (op1, 0);
6451 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6454 inner = TREE_OPERAND (inner, 0);
6459 inner = TREE_OPERAND (inner, 0);
6461 while (REFERENCE_CLASS_P (inner)
6462 && TREE_CODE (inner) != INDIRECT_REF)
6463 inner = TREE_OPERAND (inner, 0);
6466 && !DECL_EXTERNAL (inner)
6467 && !TREE_STATIC (inner)
6468 && DECL_CONTEXT (inner) == current_function_decl)
6469 warning ("function returns address of local variable");
6479 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6482 return add_stmt (build_stmt (RETURN_EXPR, retval));
6486 /* The SWITCH_STMT being built. */
6489 /* The original type of the testing expression, i.e. before the
6490 default conversion is applied. */
6493 /* A splay-tree mapping the low element of a case range to the high
6494 element, or NULL_TREE if there is no high element. Used to
6495 determine whether or not a new case label duplicates an old case
6496 label. We need a tree, rather than simply a hash table, because
6497 of the GNU case range extension. */
6500 /* The next node on the stack. */
6501 struct c_switch *next;
6504 /* A stack of the currently active switch statements. The innermost
6505 switch statement is on the top of the stack. There is no need to
6506 mark the stack for garbage collection because it is only active
6507 during the processing of the body of a function, and we never
6508 collect at that point. */
6510 struct c_switch *c_switch_stack;
6512 /* Start a C switch statement, testing expression EXP. Return the new
6516 c_start_case (tree exp)
6518 enum tree_code code;
6519 tree type, orig_type = error_mark_node;
6520 struct c_switch *cs;
6522 if (exp != error_mark_node)
6524 code = TREE_CODE (TREE_TYPE (exp));
6525 orig_type = TREE_TYPE (exp);
6527 if (!INTEGRAL_TYPE_P (orig_type)
6528 && code != ERROR_MARK)
6530 error ("switch quantity not an integer");
6531 exp = integer_zero_node;
6532 orig_type = error_mark_node;
6536 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6538 if (warn_traditional && !in_system_header
6539 && (type == long_integer_type_node
6540 || type == long_unsigned_type_node))
6541 warning ("%<long%> switch expression not converted to "
6542 "%<int%> in ISO C");
6544 exp = default_conversion (exp);
6545 type = TREE_TYPE (exp);
6549 /* Add this new SWITCH_STMT to the stack. */
6550 cs = XNEW (struct c_switch);
6551 cs->switch_stmt = build_stmt ((enum tree_code) SWITCH_STMT, exp, NULL_TREE,
6553 cs->orig_type = orig_type;
6554 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6555 cs->next = c_switch_stack;
6556 c_switch_stack = cs;
6558 return add_stmt (cs->switch_stmt);
6561 /* Process a case label. */
6564 do_case (tree low_value, tree high_value)
6566 tree label = NULL_TREE;
6570 label = c_add_case_label (c_switch_stack->cases,
6571 SWITCH_COND (c_switch_stack->switch_stmt),
6572 c_switch_stack->orig_type,
6573 low_value, high_value);
6574 if (label == error_mark_node)
6578 error ("case label not within a switch statement");
6580 error ("%<default%> label not within a switch statement");
6585 /* Finish the switch statement. */
6588 c_finish_case (tree body)
6590 struct c_switch *cs = c_switch_stack;
6592 SWITCH_BODY (cs->switch_stmt) = body;
6594 /* Emit warnings as needed. */
6595 c_do_switch_warnings (cs->cases, cs->switch_stmt);
6597 /* Pop the stack. */
6598 c_switch_stack = cs->next;
6599 splay_tree_delete (cs->cases);
6603 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6604 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6605 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6606 statement, and was not surrounded with parenthesis. */
6609 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6610 tree else_block, bool nested_if)
6614 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6615 if (warn_parentheses && nested_if && else_block == NULL)
6617 tree inner_if = then_block;
6619 /* We know from the grammar productions that there is an IF nested
6620 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6621 it might not be exactly THEN_BLOCK, but should be the last
6622 non-container statement within. */
6624 switch (TREE_CODE (inner_if))
6629 inner_if = BIND_EXPR_BODY (inner_if);
6631 case STATEMENT_LIST:
6632 inner_if = expr_last (then_block);
6634 case TRY_FINALLY_EXPR:
6635 case TRY_CATCH_EXPR:
6636 inner_if = TREE_OPERAND (inner_if, 0);
6643 if (COND_EXPR_ELSE (inner_if))
6644 warning ("%Hsuggest explicit braces to avoid ambiguous %<else%>",
6648 /* Diagnose ";" via the special empty statement node that we create. */
6651 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6654 warning ("%Hempty body in an if-statement",
6655 EXPR_LOCUS (then_block));
6656 then_block = alloc_stmt_list ();
6659 && TREE_CODE (else_block) == NOP_EXPR
6660 && !TREE_TYPE (else_block))
6662 warning ("%Hempty body in an else-statement",
6663 EXPR_LOCUS (else_block));
6664 else_block = alloc_stmt_list ();
6668 stmt = build3 (COND_EXPR, NULL_TREE, cond, then_block, else_block);
6669 SET_EXPR_LOCATION (stmt, if_locus);
6673 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6674 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6675 is false for DO loops. INCR is the FOR increment expression. BODY is
6676 the statement controlled by the loop. BLAB is the break label. CLAB is
6677 the continue label. Everything is allowed to be NULL. */
6680 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6681 tree blab, tree clab, bool cond_is_first)
6683 tree entry = NULL, exit = NULL, t;
6685 /* If the condition is zero don't generate a loop construct. */
6686 if (cond && integer_zerop (cond))
6690 t = build_and_jump (&blab);
6691 SET_EXPR_LOCATION (t, start_locus);
6697 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6699 /* If we have an exit condition, then we build an IF with gotos either
6700 out of the loop, or to the top of it. If there's no exit condition,
6701 then we just build a jump back to the top. */
6702 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6704 if (cond && !integer_nonzerop (cond))
6706 /* Canonicalize the loop condition to the end. This means
6707 generating a branch to the loop condition. Reuse the
6708 continue label, if possible. */
6713 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6714 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
6717 t = build1 (GOTO_EXPR, void_type_node, clab);
6718 SET_EXPR_LOCATION (t, start_locus);
6722 t = build_and_jump (&blab);
6723 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
6726 SET_EXPR_LOCATION (exit, start_locus);
6728 SET_EXPR_LOCATION (exit, input_location);
6737 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
6745 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
6749 c_finish_bc_stmt (tree *label_p, bool is_break)
6751 tree label = *label_p;
6754 *label_p = label = create_artificial_label ();
6755 else if (TREE_CODE (label) != LABEL_DECL)
6758 error ("break statement not within loop or switch");
6760 error ("continue statement not within a loop");
6764 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
6767 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
6770 emit_side_effect_warnings (tree expr)
6772 if (expr == error_mark_node)
6774 else if (!TREE_SIDE_EFFECTS (expr))
6776 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
6777 warning ("%Hstatement with no effect",
6778 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
6780 else if (warn_unused_value)
6781 warn_if_unused_value (expr, input_location);
6784 /* Process an expression as if it were a complete statement. Emit
6785 diagnostics, but do not call ADD_STMT. */
6788 c_process_expr_stmt (tree expr)
6793 /* Do default conversion if safe and possibly important,
6794 in case within ({...}). */
6795 if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
6796 && (flag_isoc99 || lvalue_p (expr)))
6797 || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
6798 expr = default_conversion (expr);
6800 if (warn_sequence_point)
6801 verify_sequence_points (expr);
6803 if (TREE_TYPE (expr) != error_mark_node
6804 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
6805 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
6806 error ("expression statement has incomplete type");
6808 /* If we're not processing a statement expression, warn about unused values.
6809 Warnings for statement expressions will be emitted later, once we figure
6810 out which is the result. */
6811 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
6812 && (extra_warnings || warn_unused_value))
6813 emit_side_effect_warnings (expr);
6815 /* If the expression is not of a type to which we cannot assign a line
6816 number, wrap the thing in a no-op NOP_EXPR. */
6817 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
6818 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
6821 SET_EXPR_LOCATION (expr, input_location);
6826 /* Emit an expression as a statement. */
6829 c_finish_expr_stmt (tree expr)
6832 return add_stmt (c_process_expr_stmt (expr));
6837 /* Do the opposite and emit a statement as an expression. To begin,
6838 create a new binding level and return it. */
6841 c_begin_stmt_expr (void)
6845 /* We must force a BLOCK for this level so that, if it is not expanded
6846 later, there is a way to turn off the entire subtree of blocks that
6847 are contained in it. */
6849 ret = c_begin_compound_stmt (true);
6851 /* Mark the current statement list as belonging to a statement list. */
6852 STATEMENT_LIST_STMT_EXPR (ret) = 1;
6858 c_finish_stmt_expr (tree body)
6860 tree last, type, tmp, val;
6863 body = c_end_compound_stmt (body, true);
6865 /* Locate the last statement in BODY. See c_end_compound_stmt
6866 about always returning a BIND_EXPR. */
6867 last_p = &BIND_EXPR_BODY (body);
6868 last = BIND_EXPR_BODY (body);
6871 if (TREE_CODE (last) == STATEMENT_LIST)
6873 tree_stmt_iterator i;
6875 /* This can happen with degenerate cases like ({ }). No value. */
6876 if (!TREE_SIDE_EFFECTS (last))
6879 /* If we're supposed to generate side effects warnings, process
6880 all of the statements except the last. */
6881 if (extra_warnings || warn_unused_value)
6883 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
6884 emit_side_effect_warnings (tsi_stmt (i));
6887 i = tsi_last (last);
6888 last_p = tsi_stmt_ptr (i);
6892 /* If the end of the list is exception related, then the list was split
6893 by a call to push_cleanup. Continue searching. */
6894 if (TREE_CODE (last) == TRY_FINALLY_EXPR
6895 || TREE_CODE (last) == TRY_CATCH_EXPR)
6897 last_p = &TREE_OPERAND (last, 0);
6899 goto continue_searching;
6902 /* In the case that the BIND_EXPR is not necessary, return the
6903 expression out from inside it. */
6904 if (last == error_mark_node
6905 || (last == BIND_EXPR_BODY (body)
6906 && BIND_EXPR_VARS (body) == NULL))
6909 /* Extract the type of said expression. */
6910 type = TREE_TYPE (last);
6912 /* If we're not returning a value at all, then the BIND_EXPR that
6913 we already have is a fine expression to return. */
6914 if (!type || VOID_TYPE_P (type))
6917 /* Now that we've located the expression containing the value, it seems
6918 silly to make voidify_wrapper_expr repeat the process. Create a
6919 temporary of the appropriate type and stick it in a TARGET_EXPR. */
6920 tmp = create_tmp_var_raw (type, NULL);
6922 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
6923 tree_expr_nonnegative_p giving up immediately. */
6925 if (TREE_CODE (val) == NOP_EXPR
6926 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
6927 val = TREE_OPERAND (val, 0);
6929 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
6930 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
6932 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
6935 /* Begin and end compound statements. This is as simple as pushing
6936 and popping new statement lists from the tree. */
6939 c_begin_compound_stmt (bool do_scope)
6941 tree stmt = push_stmt_list ();
6948 c_end_compound_stmt (tree stmt, bool do_scope)
6954 if (c_dialect_objc ())
6955 objc_clear_super_receiver ();
6956 block = pop_scope ();
6959 stmt = pop_stmt_list (stmt);
6960 stmt = c_build_bind_expr (block, stmt);
6962 /* If this compound statement is nested immediately inside a statement
6963 expression, then force a BIND_EXPR to be created. Otherwise we'll
6964 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
6965 STATEMENT_LISTs merge, and thus we can lose track of what statement
6968 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
6969 && TREE_CODE (stmt) != BIND_EXPR)
6971 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
6972 TREE_SIDE_EFFECTS (stmt) = 1;
6978 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
6979 when the current scope is exited. EH_ONLY is true when this is not
6980 meant to apply to normal control flow transfer. */
6983 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
6985 enum tree_code code;
6989 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
6990 stmt = build_stmt (code, NULL, cleanup);
6992 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
6993 list = push_stmt_list ();
6994 TREE_OPERAND (stmt, 0) = list;
6995 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
6998 /* Build a binary-operation expression without default conversions.
6999 CODE is the kind of expression to build.
7000 This function differs from `build' in several ways:
7001 the data type of the result is computed and recorded in it,
7002 warnings are generated if arg data types are invalid,
7003 special handling for addition and subtraction of pointers is known,
7004 and some optimization is done (operations on narrow ints
7005 are done in the narrower type when that gives the same result).
7006 Constant folding is also done before the result is returned.
7008 Note that the operands will never have enumeral types, or function
7009 or array types, because either they will have the default conversions
7010 performed or they have both just been converted to some other type in which
7011 the arithmetic is to be done. */
7014 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7018 enum tree_code code0, code1;
7021 /* Expression code to give to the expression when it is built.
7022 Normally this is CODE, which is what the caller asked for,
7023 but in some special cases we change it. */
7024 enum tree_code resultcode = code;
7026 /* Data type in which the computation is to be performed.
7027 In the simplest cases this is the common type of the arguments. */
7028 tree result_type = NULL;
7030 /* Nonzero means operands have already been type-converted
7031 in whatever way is necessary.
7032 Zero means they need to be converted to RESULT_TYPE. */
7035 /* Nonzero means create the expression with this type, rather than
7037 tree build_type = 0;
7039 /* Nonzero means after finally constructing the expression
7040 convert it to this type. */
7041 tree final_type = 0;
7043 /* Nonzero if this is an operation like MIN or MAX which can
7044 safely be computed in short if both args are promoted shorts.
7045 Also implies COMMON.
7046 -1 indicates a bitwise operation; this makes a difference
7047 in the exact conditions for when it is safe to do the operation
7048 in a narrower mode. */
7051 /* Nonzero if this is a comparison operation;
7052 if both args are promoted shorts, compare the original shorts.
7053 Also implies COMMON. */
7054 int short_compare = 0;
7056 /* Nonzero if this is a right-shift operation, which can be computed on the
7057 original short and then promoted if the operand is a promoted short. */
7058 int short_shift = 0;
7060 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7065 op0 = default_conversion (orig_op0);
7066 op1 = default_conversion (orig_op1);
7074 type0 = TREE_TYPE (op0);
7075 type1 = TREE_TYPE (op1);
7077 /* The expression codes of the data types of the arguments tell us
7078 whether the arguments are integers, floating, pointers, etc. */
7079 code0 = TREE_CODE (type0);
7080 code1 = TREE_CODE (type1);
7082 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7083 STRIP_TYPE_NOPS (op0);
7084 STRIP_TYPE_NOPS (op1);
7086 /* If an error was already reported for one of the arguments,
7087 avoid reporting another error. */
7089 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7090 return error_mark_node;
7095 /* Handle the pointer + int case. */
7096 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7097 return pointer_int_sum (PLUS_EXPR, op0, op1);
7098 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7099 return pointer_int_sum (PLUS_EXPR, op1, op0);
7105 /* Subtraction of two similar pointers.
7106 We must subtract them as integers, then divide by object size. */
7107 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7108 && comp_target_types (type0, type1, 1))
7109 return pointer_diff (op0, op1);
7110 /* Handle pointer minus int. Just like pointer plus int. */
7111 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7112 return pointer_int_sum (MINUS_EXPR, op0, op1);
7121 case TRUNC_DIV_EXPR:
7123 case FLOOR_DIV_EXPR:
7124 case ROUND_DIV_EXPR:
7125 case EXACT_DIV_EXPR:
7126 /* Floating point division by zero is a legitimate way to obtain
7127 infinities and NaNs. */
7128 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7129 warning ("division by zero");
7131 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7132 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7133 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7134 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7136 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7137 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7138 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7139 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7141 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
7142 resultcode = RDIV_EXPR;
7144 /* Although it would be tempting to shorten always here, that
7145 loses on some targets, since the modulo instruction is
7146 undefined if the quotient can't be represented in the
7147 computation mode. We shorten only if unsigned or if
7148 dividing by something we know != -1. */
7149 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7150 || (TREE_CODE (op1) == INTEGER_CST
7151 && !integer_all_onesp (op1)));
7159 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7161 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7165 case TRUNC_MOD_EXPR:
7166 case FLOOR_MOD_EXPR:
7167 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7168 warning ("division by zero");
7170 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7172 /* Although it would be tempting to shorten always here, that loses
7173 on some targets, since the modulo instruction is undefined if the
7174 quotient can't be represented in the computation mode. We shorten
7175 only if unsigned or if dividing by something we know != -1. */
7176 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7177 || (TREE_CODE (op1) == INTEGER_CST
7178 && !integer_all_onesp (op1)));
7183 case TRUTH_ANDIF_EXPR:
7184 case TRUTH_ORIF_EXPR:
7185 case TRUTH_AND_EXPR:
7187 case TRUTH_XOR_EXPR:
7188 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7189 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7190 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7191 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7193 /* Result of these operations is always an int,
7194 but that does not mean the operands should be
7195 converted to ints! */
7196 result_type = integer_type_node;
7197 op0 = lang_hooks.truthvalue_conversion (op0);
7198 op1 = lang_hooks.truthvalue_conversion (op1);
7203 /* Shift operations: result has same type as first operand;
7204 always convert second operand to int.
7205 Also set SHORT_SHIFT if shifting rightward. */
7208 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7210 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7212 if (tree_int_cst_sgn (op1) < 0)
7213 warning ("right shift count is negative");
7216 if (!integer_zerop (op1))
7219 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7220 warning ("right shift count >= width of type");
7224 /* Use the type of the value to be shifted. */
7225 result_type = type0;
7226 /* Convert the shift-count to an integer, regardless of size
7227 of value being shifted. */
7228 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7229 op1 = convert (integer_type_node, op1);
7230 /* Avoid converting op1 to result_type later. */
7236 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7238 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7240 if (tree_int_cst_sgn (op1) < 0)
7241 warning ("left shift count is negative");
7243 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7244 warning ("left shift count >= width of type");
7247 /* Use the type of the value to be shifted. */
7248 result_type = type0;
7249 /* Convert the shift-count to an integer, regardless of size
7250 of value being shifted. */
7251 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7252 op1 = convert (integer_type_node, op1);
7253 /* Avoid converting op1 to result_type later. */
7260 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
7261 warning ("comparing floating point with == or != is unsafe");
7262 /* Result of comparison is always int,
7263 but don't convert the args to int! */
7264 build_type = integer_type_node;
7265 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7266 || code0 == COMPLEX_TYPE)
7267 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7268 || code1 == COMPLEX_TYPE))
7270 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7272 tree tt0 = TREE_TYPE (type0);
7273 tree tt1 = TREE_TYPE (type1);
7274 /* Anything compares with void *. void * compares with anything.
7275 Otherwise, the targets must be compatible
7276 and both must be object or both incomplete. */
7277 if (comp_target_types (type0, type1, 1))
7278 result_type = common_pointer_type (type0, type1);
7279 else if (VOID_TYPE_P (tt0))
7281 /* op0 != orig_op0 detects the case of something
7282 whose value is 0 but which isn't a valid null ptr const. */
7283 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7284 && TREE_CODE (tt1) == FUNCTION_TYPE)
7285 pedwarn ("ISO C forbids comparison of %<void *%>"
7286 " with function pointer");
7288 else if (VOID_TYPE_P (tt1))
7290 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7291 && TREE_CODE (tt0) == FUNCTION_TYPE)
7292 pedwarn ("ISO C forbids comparison of %<void *%>"
7293 " with function pointer");
7296 pedwarn ("comparison of distinct pointer types lacks a cast");
7298 if (result_type == NULL_TREE)
7299 result_type = ptr_type_node;
7301 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7302 && integer_zerop (op1))
7303 result_type = type0;
7304 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7305 && integer_zerop (op0))
7306 result_type = type1;
7307 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7309 result_type = type0;
7310 pedwarn ("comparison between pointer and integer");
7312 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7314 result_type = type1;
7315 pedwarn ("comparison between pointer and integer");
7323 build_type = integer_type_node;
7324 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7325 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7327 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7329 if (comp_target_types (type0, type1, 1))
7331 result_type = common_pointer_type (type0, type1);
7332 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7333 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7334 pedwarn ("comparison of complete and incomplete pointers");
7336 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7337 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7341 result_type = ptr_type_node;
7342 pedwarn ("comparison of distinct pointer types lacks a cast");
7345 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7346 && integer_zerop (op1))
7348 result_type = type0;
7349 if (pedantic || extra_warnings)
7350 pedwarn ("ordered comparison of pointer with integer zero");
7352 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7353 && integer_zerop (op0))
7355 result_type = type1;
7357 pedwarn ("ordered comparison of pointer with integer zero");
7359 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7361 result_type = type0;
7362 pedwarn ("comparison between pointer and integer");
7364 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7366 result_type = type1;
7367 pedwarn ("comparison between pointer and integer");
7375 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7376 return error_mark_node;
7378 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7379 || code0 == VECTOR_TYPE)
7381 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7382 || code1 == VECTOR_TYPE))
7384 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7386 if (shorten || common || short_compare)
7387 result_type = common_type (type0, type1);
7389 /* For certain operations (which identify themselves by shorten != 0)
7390 if both args were extended from the same smaller type,
7391 do the arithmetic in that type and then extend.
7393 shorten !=0 and !=1 indicates a bitwise operation.
7394 For them, this optimization is safe only if
7395 both args are zero-extended or both are sign-extended.
7396 Otherwise, we might change the result.
7397 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7398 but calculated in (unsigned short) it would be (unsigned short)-1. */
7400 if (shorten && none_complex)
7402 int unsigned0, unsigned1;
7403 tree arg0 = get_narrower (op0, &unsigned0);
7404 tree arg1 = get_narrower (op1, &unsigned1);
7405 /* UNS is 1 if the operation to be done is an unsigned one. */
7406 int uns = TYPE_UNSIGNED (result_type);
7409 final_type = result_type;
7411 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7412 but it *requires* conversion to FINAL_TYPE. */
7414 if ((TYPE_PRECISION (TREE_TYPE (op0))
7415 == TYPE_PRECISION (TREE_TYPE (arg0)))
7416 && TREE_TYPE (op0) != final_type)
7417 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7418 if ((TYPE_PRECISION (TREE_TYPE (op1))
7419 == TYPE_PRECISION (TREE_TYPE (arg1)))
7420 && TREE_TYPE (op1) != final_type)
7421 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7423 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7425 /* For bitwise operations, signedness of nominal type
7426 does not matter. Consider only how operands were extended. */
7430 /* Note that in all three cases below we refrain from optimizing
7431 an unsigned operation on sign-extended args.
7432 That would not be valid. */
7434 /* Both args variable: if both extended in same way
7435 from same width, do it in that width.
7436 Do it unsigned if args were zero-extended. */
7437 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7438 < TYPE_PRECISION (result_type))
7439 && (TYPE_PRECISION (TREE_TYPE (arg1))
7440 == TYPE_PRECISION (TREE_TYPE (arg0)))
7441 && unsigned0 == unsigned1
7442 && (unsigned0 || !uns))
7444 = c_common_signed_or_unsigned_type
7445 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7446 else if (TREE_CODE (arg0) == INTEGER_CST
7447 && (unsigned1 || !uns)
7448 && (TYPE_PRECISION (TREE_TYPE (arg1))
7449 < TYPE_PRECISION (result_type))
7451 = c_common_signed_or_unsigned_type (unsigned1,
7453 int_fits_type_p (arg0, type)))
7455 else if (TREE_CODE (arg1) == INTEGER_CST
7456 && (unsigned0 || !uns)
7457 && (TYPE_PRECISION (TREE_TYPE (arg0))
7458 < TYPE_PRECISION (result_type))
7460 = c_common_signed_or_unsigned_type (unsigned0,
7462 int_fits_type_p (arg1, type)))
7466 /* Shifts can be shortened if shifting right. */
7471 tree arg0 = get_narrower (op0, &unsigned_arg);
7473 final_type = result_type;
7475 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7476 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7478 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7479 /* We can shorten only if the shift count is less than the
7480 number of bits in the smaller type size. */
7481 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7482 /* We cannot drop an unsigned shift after sign-extension. */
7483 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7485 /* Do an unsigned shift if the operand was zero-extended. */
7487 = c_common_signed_or_unsigned_type (unsigned_arg,
7489 /* Convert value-to-be-shifted to that type. */
7490 if (TREE_TYPE (op0) != result_type)
7491 op0 = convert (result_type, op0);
7496 /* Comparison operations are shortened too but differently.
7497 They identify themselves by setting short_compare = 1. */
7501 /* Don't write &op0, etc., because that would prevent op0
7502 from being kept in a register.
7503 Instead, make copies of the our local variables and
7504 pass the copies by reference, then copy them back afterward. */
7505 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7506 enum tree_code xresultcode = resultcode;
7508 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7513 op0 = xop0, op1 = xop1;
7515 resultcode = xresultcode;
7517 if (warn_sign_compare && skip_evaluation == 0)
7519 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7520 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7521 int unsignedp0, unsignedp1;
7522 tree primop0 = get_narrower (op0, &unsignedp0);
7523 tree primop1 = get_narrower (op1, &unsignedp1);
7527 STRIP_TYPE_NOPS (xop0);
7528 STRIP_TYPE_NOPS (xop1);
7530 /* Give warnings for comparisons between signed and unsigned
7531 quantities that may fail.
7533 Do the checking based on the original operand trees, so that
7534 casts will be considered, but default promotions won't be.
7536 Do not warn if the comparison is being done in a signed type,
7537 since the signed type will only be chosen if it can represent
7538 all the values of the unsigned type. */
7539 if (!TYPE_UNSIGNED (result_type))
7541 /* Do not warn if both operands are the same signedness. */
7542 else if (op0_signed == op1_signed)
7549 sop = xop0, uop = xop1;
7551 sop = xop1, uop = xop0;
7553 /* Do not warn if the signed quantity is an
7554 unsuffixed integer literal (or some static
7555 constant expression involving such literals or a
7556 conditional expression involving such literals)
7557 and it is non-negative. */
7558 if (tree_expr_nonnegative_p (sop))
7560 /* Do not warn if the comparison is an equality operation,
7561 the unsigned quantity is an integral constant, and it
7562 would fit in the result if the result were signed. */
7563 else if (TREE_CODE (uop) == INTEGER_CST
7564 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
7566 (uop, c_common_signed_type (result_type)))
7568 /* Do not warn if the unsigned quantity is an enumeration
7569 constant and its maximum value would fit in the result
7570 if the result were signed. */
7571 else if (TREE_CODE (uop) == INTEGER_CST
7572 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
7574 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
7575 c_common_signed_type (result_type)))
7578 warning ("comparison between signed and unsigned");
7581 /* Warn if two unsigned values are being compared in a size
7582 larger than their original size, and one (and only one) is the
7583 result of a `~' operator. This comparison will always fail.
7585 Also warn if one operand is a constant, and the constant
7586 does not have all bits set that are set in the ~ operand
7587 when it is extended. */
7589 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
7590 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
7592 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
7593 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
7596 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
7599 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
7602 HOST_WIDE_INT constant, mask;
7603 int unsignedp, bits;
7605 if (host_integerp (primop0, 0))
7608 unsignedp = unsignedp1;
7609 constant = tree_low_cst (primop0, 0);
7614 unsignedp = unsignedp0;
7615 constant = tree_low_cst (primop1, 0);
7618 bits = TYPE_PRECISION (TREE_TYPE (primop));
7619 if (bits < TYPE_PRECISION (result_type)
7620 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
7622 mask = (~(HOST_WIDE_INT) 0) << bits;
7623 if ((mask & constant) != mask)
7624 warning ("comparison of promoted ~unsigned with constant");
7627 else if (unsignedp0 && unsignedp1
7628 && (TYPE_PRECISION (TREE_TYPE (primop0))
7629 < TYPE_PRECISION (result_type))
7630 && (TYPE_PRECISION (TREE_TYPE (primop1))
7631 < TYPE_PRECISION (result_type)))
7632 warning ("comparison of promoted ~unsigned with unsigned");
7638 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
7639 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
7640 Then the expression will be built.
7641 It will be given type FINAL_TYPE if that is nonzero;
7642 otherwise, it will be given type RESULT_TYPE. */
7646 binary_op_error (code);
7647 return error_mark_node;
7652 if (TREE_TYPE (op0) != result_type)
7653 op0 = convert (result_type, op0);
7654 if (TREE_TYPE (op1) != result_type)
7655 op1 = convert (result_type, op1);
7657 /* This can happen if one operand has a vector type, and the other
7658 has a different type. */
7659 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
7660 return error_mark_node;
7663 if (build_type == NULL_TREE)
7664 build_type = result_type;
7667 tree result = build2 (resultcode, build_type, op0, op1);
7669 /* Treat expressions in initializers specially as they can't trap. */
7670 result = require_constant_value ? fold_initializer (result)
7673 if (final_type != 0)
7674 result = convert (final_type, result);