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"
46 #include "tree-flow.h"
48 /* Possible cases of implicit bad conversions. Used to select
49 diagnostic messages in convert_for_assignment. */
58 /* The level of nesting inside "__alignof__". */
61 /* The level of nesting inside "sizeof". */
64 /* The level of nesting inside "typeof". */
67 struct c_label_context *label_context_stack;
69 /* Nonzero if we've already printed a "missing braces around initializer"
70 message within this initializer. */
71 static int missing_braces_mentioned;
73 static int require_constant_value;
74 static int require_constant_elements;
76 static tree qualify_type (tree, tree);
77 static int tagged_types_tu_compatible_p (tree, tree);
78 static int comp_target_types (tree, tree, int);
79 static int function_types_compatible_p (tree, tree);
80 static int type_lists_compatible_p (tree, tree);
81 static tree decl_constant_value_for_broken_optimization (tree);
82 static tree default_function_array_conversion (tree);
83 static tree lookup_field (tree, tree);
84 static tree convert_arguments (tree, tree, tree, tree);
85 static tree pointer_diff (tree, tree);
86 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
88 static tree valid_compound_expr_initializer (tree, tree);
89 static void push_string (const char *);
90 static void push_member_name (tree);
91 static void push_array_bounds (int);
92 static int spelling_length (void);
93 static char *print_spelling (char *);
94 static void warning_init (const char *);
95 static tree digest_init (tree, tree, bool, int);
96 static void output_init_element (tree, bool, tree, tree, int);
97 static void output_pending_init_elements (int);
98 static int set_designator (int);
99 static void push_range_stack (tree);
100 static void add_pending_init (tree, tree);
101 static void set_nonincremental_init (void);
102 static void set_nonincremental_init_from_string (tree);
103 static tree find_init_member (tree);
104 static void readonly_error (tree, enum lvalue_use);
105 static void record_maybe_used_decl (tree);
107 /* Do `exp = require_complete_type (exp);' to make sure exp
108 does not have an incomplete type. (That includes void types.) */
111 require_complete_type (tree value)
113 tree type = TREE_TYPE (value);
115 if (value == error_mark_node || type == error_mark_node)
116 return error_mark_node;
118 /* First, detect a valid value with a complete type. */
119 if (COMPLETE_TYPE_P (type))
122 c_incomplete_type_error (value, type);
123 return error_mark_node;
126 /* Print an error message for invalid use of an incomplete type.
127 VALUE is the expression that was used (or 0 if that isn't known)
128 and TYPE is the type that was invalid. */
131 c_incomplete_type_error (tree value, tree type)
133 const char *type_code_string;
135 /* Avoid duplicate error message. */
136 if (TREE_CODE (type) == ERROR_MARK)
139 if (value != 0 && (TREE_CODE (value) == VAR_DECL
140 || TREE_CODE (value) == PARM_DECL))
141 error ("%qs has an incomplete type",
142 IDENTIFIER_POINTER (DECL_NAME (value)));
146 /* We must print an error message. Be clever about what it says. */
148 switch (TREE_CODE (type))
151 type_code_string = "struct";
155 type_code_string = "union";
159 type_code_string = "enum";
163 error ("invalid use of void expression");
167 if (TYPE_DOMAIN (type))
169 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
171 error ("invalid use of flexible array member");
174 type = TREE_TYPE (type);
177 error ("invalid use of array with unspecified bounds");
184 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
185 error ("invalid use of undefined type %<%s %s%>",
186 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
188 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
189 error ("invalid use of incomplete typedef %qs",
190 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
194 /* Given a type, apply default promotions wrt unnamed function
195 arguments and return the new type. */
198 c_type_promotes_to (tree type)
200 if (TYPE_MAIN_VARIANT (type) == float_type_node)
201 return double_type_node;
203 if (c_promoting_integer_type_p (type))
205 /* Preserve unsignedness if not really getting any wider. */
206 if (TYPE_UNSIGNED (type)
207 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
208 return unsigned_type_node;
209 return integer_type_node;
215 /* Return a variant of TYPE which has all the type qualifiers of LIKE
216 as well as those of TYPE. */
219 qualify_type (tree type, tree like)
221 return c_build_qualified_type (type,
222 TYPE_QUALS (type) | TYPE_QUALS (like));
225 /* Return the composite type of two compatible types.
227 We assume that comptypes has already been done and returned
228 nonzero; if that isn't so, this may crash. In particular, we
229 assume that qualifiers match. */
232 composite_type (tree t1, tree t2)
234 enum tree_code code1;
235 enum tree_code code2;
238 /* Save time if the two types are the same. */
240 if (t1 == t2) return t1;
242 /* If one type is nonsense, use the other. */
243 if (t1 == error_mark_node)
245 if (t2 == error_mark_node)
248 code1 = TREE_CODE (t1);
249 code2 = TREE_CODE (t2);
251 /* Merge the attributes. */
252 attributes = targetm.merge_type_attributes (t1, t2);
254 /* If one is an enumerated type and the other is the compatible
255 integer type, the composite type might be either of the two
256 (DR#013 question 3). For consistency, use the enumerated type as
257 the composite type. */
259 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
261 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
264 gcc_assert (code1 == code2);
269 /* For two pointers, do this recursively on the target type. */
271 tree pointed_to_1 = TREE_TYPE (t1);
272 tree pointed_to_2 = TREE_TYPE (t2);
273 tree target = composite_type (pointed_to_1, pointed_to_2);
274 t1 = build_pointer_type (target);
275 t1 = build_type_attribute_variant (t1, attributes);
276 return qualify_type (t1, t2);
281 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
285 /* We should not have any type quals on arrays at all. */
286 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
288 /* Save space: see if the result is identical to one of the args. */
289 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
290 return build_type_attribute_variant (t1, attributes);
291 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
292 return build_type_attribute_variant (t2, attributes);
294 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
295 return build_type_attribute_variant (t1, attributes);
296 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
297 return build_type_attribute_variant (t2, attributes);
299 /* Merge the element types, and have a size if either arg has
300 one. We may have qualifiers on the element types. To set
301 up TYPE_MAIN_VARIANT correctly, we need to form the
302 composite of the unqualified types and add the qualifiers
304 quals = TYPE_QUALS (strip_array_types (elt));
305 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
306 t1 = build_array_type (unqual_elt,
307 TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
308 t1 = c_build_qualified_type (t1, quals);
309 return build_type_attribute_variant (t1, attributes);
313 /* Function types: prefer the one that specified arg types.
314 If both do, merge the arg types. Also merge the return types. */
316 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
317 tree p1 = TYPE_ARG_TYPES (t1);
318 tree p2 = TYPE_ARG_TYPES (t2);
323 /* Save space: see if the result is identical to one of the args. */
324 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
325 return build_type_attribute_variant (t1, attributes);
326 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
327 return build_type_attribute_variant (t2, attributes);
329 /* Simple way if one arg fails to specify argument types. */
330 if (TYPE_ARG_TYPES (t1) == 0)
332 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
333 t1 = build_type_attribute_variant (t1, attributes);
334 return qualify_type (t1, t2);
336 if (TYPE_ARG_TYPES (t2) == 0)
338 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
339 t1 = build_type_attribute_variant (t1, attributes);
340 return qualify_type (t1, t2);
343 /* If both args specify argument types, we must merge the two
344 lists, argument by argument. */
345 /* Tell global_bindings_p to return false so that variable_size
346 doesn't abort on VLAs in parameter types. */
347 c_override_global_bindings_to_false = true;
349 len = list_length (p1);
352 for (i = 0; i < len; i++)
353 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
358 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
360 /* A null type means arg type is not specified.
361 Take whatever the other function type has. */
362 if (TREE_VALUE (p1) == 0)
364 TREE_VALUE (n) = TREE_VALUE (p2);
367 if (TREE_VALUE (p2) == 0)
369 TREE_VALUE (n) = TREE_VALUE (p1);
373 /* Given wait (union {union wait *u; int *i} *)
374 and wait (union wait *),
375 prefer union wait * as type of parm. */
376 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
377 && TREE_VALUE (p1) != TREE_VALUE (p2))
380 tree mv2 = TREE_VALUE (p2);
381 if (mv2 && mv2 != error_mark_node
382 && TREE_CODE (mv2) != ARRAY_TYPE)
383 mv2 = TYPE_MAIN_VARIANT (mv2);
384 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
385 memb; memb = TREE_CHAIN (memb))
387 tree mv3 = TREE_TYPE (memb);
388 if (mv3 && mv3 != error_mark_node
389 && TREE_CODE (mv3) != ARRAY_TYPE)
390 mv3 = TYPE_MAIN_VARIANT (mv3);
391 if (comptypes (mv3, mv2))
393 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
396 pedwarn ("function types not truly compatible in ISO C");
401 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
402 && TREE_VALUE (p2) != TREE_VALUE (p1))
405 tree mv1 = TREE_VALUE (p1);
406 if (mv1 && mv1 != error_mark_node
407 && TREE_CODE (mv1) != ARRAY_TYPE)
408 mv1 = TYPE_MAIN_VARIANT (mv1);
409 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
410 memb; memb = TREE_CHAIN (memb))
412 tree mv3 = TREE_TYPE (memb);
413 if (mv3 && mv3 != error_mark_node
414 && TREE_CODE (mv3) != ARRAY_TYPE)
415 mv3 = TYPE_MAIN_VARIANT (mv3);
416 if (comptypes (mv3, mv1))
418 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
421 pedwarn ("function types not truly compatible in ISO C");
426 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
430 c_override_global_bindings_to_false = false;
431 t1 = build_function_type (valtype, newargs);
432 t1 = qualify_type (t1, t2);
433 /* ... falls through ... */
437 return build_type_attribute_variant (t1, attributes);
442 /* Return the type of a conditional expression between pointers to
443 possibly differently qualified versions of compatible types.
445 We assume that comp_target_types has already been done and returned
446 nonzero; if that isn't so, this may crash. */
449 common_pointer_type (tree t1, tree t2)
452 tree pointed_to_1, mv1;
453 tree pointed_to_2, mv2;
456 /* Save time if the two types are the same. */
458 if (t1 == t2) return t1;
460 /* If one type is nonsense, use the other. */
461 if (t1 == error_mark_node)
463 if (t2 == error_mark_node)
466 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
467 && TREE_CODE (t2) == POINTER_TYPE);
469 /* Merge the attributes. */
470 attributes = targetm.merge_type_attributes (t1, t2);
472 /* Find the composite type of the target types, and combine the
473 qualifiers of the two types' targets. Do not lose qualifiers on
474 array element types by taking the TYPE_MAIN_VARIANT. */
475 mv1 = pointed_to_1 = TREE_TYPE (t1);
476 mv2 = pointed_to_2 = TREE_TYPE (t2);
477 if (TREE_CODE (mv1) != ARRAY_TYPE)
478 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
479 if (TREE_CODE (mv2) != ARRAY_TYPE)
480 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
481 target = composite_type (mv1, mv2);
482 t1 = build_pointer_type (c_build_qualified_type
484 TYPE_QUALS (pointed_to_1) |
485 TYPE_QUALS (pointed_to_2)));
486 return build_type_attribute_variant (t1, attributes);
489 /* Return the common type for two arithmetic types under the usual
490 arithmetic conversions. The default conversions have already been
491 applied, and enumerated types converted to their compatible integer
492 types. The resulting type is unqualified and has no attributes.
494 This is the type for the result of most arithmetic operations
495 if the operands have the given two types. */
498 c_common_type (tree t1, tree t2)
500 enum tree_code code1;
501 enum tree_code code2;
503 /* If one type is nonsense, use the other. */
504 if (t1 == error_mark_node)
506 if (t2 == error_mark_node)
509 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
510 t1 = TYPE_MAIN_VARIANT (t1);
512 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
513 t2 = TYPE_MAIN_VARIANT (t2);
515 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
516 t1 = build_type_attribute_variant (t1, NULL_TREE);
518 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
519 t2 = build_type_attribute_variant (t2, NULL_TREE);
521 /* Save time if the two types are the same. */
523 if (t1 == t2) return t1;
525 code1 = TREE_CODE (t1);
526 code2 = TREE_CODE (t2);
528 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
529 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
530 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
531 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
533 /* If one type is a vector type, return that type. (How the usual
534 arithmetic conversions apply to the vector types extension is not
535 precisely specified.) */
536 if (code1 == VECTOR_TYPE)
539 if (code2 == VECTOR_TYPE)
542 /* If one type is complex, form the common type of the non-complex
543 components, then make that complex. Use T1 or T2 if it is the
545 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
547 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
548 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
549 tree subtype = c_common_type (subtype1, subtype2);
551 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
553 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
556 return build_complex_type (subtype);
559 /* If only one is real, use it as the result. */
561 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
564 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
567 /* Both real or both integers; use the one with greater precision. */
569 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
571 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
574 /* Same precision. Prefer long longs to longs to ints when the
575 same precision, following the C99 rules on integer type rank
576 (which are equivalent to the C90 rules for C90 types). */
578 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
579 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
580 return long_long_unsigned_type_node;
582 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
583 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
585 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
586 return long_long_unsigned_type_node;
588 return long_long_integer_type_node;
591 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
592 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
593 return long_unsigned_type_node;
595 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
596 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
598 /* But preserve unsignedness from the other type,
599 since long cannot hold all the values of an unsigned int. */
600 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
601 return long_unsigned_type_node;
603 return long_integer_type_node;
606 /* Likewise, prefer long double to double even if same size. */
607 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
608 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
609 return long_double_type_node;
611 /* Otherwise prefer the unsigned one. */
613 if (TYPE_UNSIGNED (t1))
619 /* Wrapper around c_common_type that is used by c-common.c. ENUMERAL_TYPEs
620 are allowed here and are converted to their compatible integer types. */
622 common_type (tree t1, tree t2)
624 if (TREE_CODE (t1) == ENUMERAL_TYPE)
625 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
626 if (TREE_CODE (t2) == ENUMERAL_TYPE)
627 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
628 return c_common_type (t1, t2);
631 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
632 or various other operations. Return 2 if they are compatible
633 but a warning may be needed if you use them together. */
636 comptypes (tree type1, tree type2)
642 /* Suppress errors caused by previously reported errors. */
644 if (t1 == t2 || !t1 || !t2
645 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
648 /* If either type is the internal version of sizetype, return the
650 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
651 && TYPE_ORIG_SIZE_TYPE (t1))
652 t1 = TYPE_ORIG_SIZE_TYPE (t1);
654 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
655 && TYPE_ORIG_SIZE_TYPE (t2))
656 t2 = TYPE_ORIG_SIZE_TYPE (t2);
659 /* Enumerated types are compatible with integer types, but this is
660 not transitive: two enumerated types in the same translation unit
661 are compatible with each other only if they are the same type. */
663 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
664 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
665 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
666 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
671 /* Different classes of types can't be compatible. */
673 if (TREE_CODE (t1) != TREE_CODE (t2))
676 /* Qualifiers must match. C99 6.7.3p9 */
678 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
681 /* Allow for two different type nodes which have essentially the same
682 definition. Note that we already checked for equality of the type
683 qualifiers (just above). */
685 if (TREE_CODE (t1) != ARRAY_TYPE
686 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
689 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
690 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
693 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
696 switch (TREE_CODE (t1))
699 /* We must give ObjC the first crack at comparing pointers, since
700 protocol qualifiers may be involved. */
701 if (c_dialect_objc () && (val = objc_comptypes (t1, t2, 0)) >= 0)
703 /* Do not remove mode or aliasing information. */
704 if (TYPE_MODE (t1) != TYPE_MODE (t2)
705 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
707 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
708 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
712 val = function_types_compatible_p (t1, t2);
717 tree d1 = TYPE_DOMAIN (t1);
718 tree d2 = TYPE_DOMAIN (t2);
719 bool d1_variable, d2_variable;
720 bool d1_zero, d2_zero;
723 /* Target types must match incl. qualifiers. */
724 if (TREE_TYPE (t1) != TREE_TYPE (t2)
725 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
728 /* Sizes must match unless one is missing or variable. */
729 if (d1 == 0 || d2 == 0 || d1 == d2)
732 d1_zero = !TYPE_MAX_VALUE (d1);
733 d2_zero = !TYPE_MAX_VALUE (d2);
735 d1_variable = (!d1_zero
736 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
737 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
738 d2_variable = (!d2_zero
739 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
740 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
742 if (d1_variable || d2_variable)
744 if (d1_zero && d2_zero)
746 if (d1_zero || d2_zero
747 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
748 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
755 /* We are dealing with two distinct structs. In assorted Objective-C
756 corner cases, however, these can still be deemed equivalent. */
757 if (c_dialect_objc () && objc_comptypes (t1, t2, 0) == 1)
762 if (val != 1 && !same_translation_unit_p (t1, t2))
763 val = tagged_types_tu_compatible_p (t1, t2);
767 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
768 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2));
774 return attrval == 2 && val == 1 ? 2 : val;
777 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
778 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
779 to 1 or 0 depending if the check of the pointer types is meant to
780 be reflexive or not (typically, assignments are not reflexive,
781 while comparisons are reflexive).
785 comp_target_types (tree ttl, tree ttr, int reflexive)
790 /* Give objc_comptypes a crack at letting these types through. */
791 if ((val = objc_comptypes (ttl, ttr, reflexive)) >= 0)
794 /* Do not lose qualifiers on element types of array types that are
795 pointer targets by taking their TYPE_MAIN_VARIANT. */
796 mvl = TREE_TYPE (ttl);
797 mvr = TREE_TYPE (ttr);
798 if (TREE_CODE (mvl) != ARRAY_TYPE)
799 mvl = TYPE_MAIN_VARIANT (mvl);
800 if (TREE_CODE (mvr) != ARRAY_TYPE)
801 mvr = TYPE_MAIN_VARIANT (mvr);
802 val = comptypes (mvl, mvr);
804 if (val == 2 && pedantic)
805 pedwarn ("types are not quite compatible");
809 /* Subroutines of `comptypes'. */
811 /* Determine whether two trees derive from the same translation unit.
812 If the CONTEXT chain ends in a null, that tree's context is still
813 being parsed, so if two trees have context chains ending in null,
814 they're in the same translation unit. */
816 same_translation_unit_p (tree t1, tree t2)
818 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
819 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
821 case tcc_declaration:
822 t1 = DECL_CONTEXT (t1); break;
824 t1 = TYPE_CONTEXT (t1); break;
825 case tcc_exceptional:
826 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
827 default: gcc_unreachable ();
830 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
831 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
833 case tcc_declaration:
834 t2 = DECL_CONTEXT (t2); break;
836 t2 = TYPE_CONTEXT (t2); break;
837 case tcc_exceptional:
838 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
839 default: gcc_unreachable ();
845 /* The C standard says that two structures in different translation
846 units are compatible with each other only if the types of their
847 fields are compatible (among other things). So, consider two copies
848 of this structure: */
850 struct tagged_tu_seen {
851 const struct tagged_tu_seen * next;
856 /* Can they be compatible with each other? We choose to break the
857 recursion by allowing those types to be compatible. */
859 static const struct tagged_tu_seen * tagged_tu_seen_base;
861 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
862 compatible. If the two types are not the same (which has been
863 checked earlier), this can only happen when multiple translation
864 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
868 tagged_types_tu_compatible_p (tree t1, tree t2)
871 bool needs_warning = false;
873 /* We have to verify that the tags of the types are the same. This
874 is harder than it looks because this may be a typedef, so we have
875 to go look at the original type. It may even be a typedef of a
877 In the case of compiler-created builtin structs the TYPE_DECL
878 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
879 while (TYPE_NAME (t1)
880 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
881 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
882 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
884 while (TYPE_NAME (t2)
885 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
886 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
887 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
889 /* C90 didn't have the requirement that the two tags be the same. */
890 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
893 /* C90 didn't say what happened if one or both of the types were
894 incomplete; we choose to follow C99 rules here, which is that they
896 if (TYPE_SIZE (t1) == NULL
897 || TYPE_SIZE (t2) == NULL)
901 const struct tagged_tu_seen * tts_i;
902 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
903 if (tts_i->t1 == t1 && tts_i->t2 == t2)
907 switch (TREE_CODE (t1))
912 /* Speed up the case where the type values are in the same order. */
913 tree tv1 = TYPE_VALUES (t1);
914 tree tv2 = TYPE_VALUES (t2);
919 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
921 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
923 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
927 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
929 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
932 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
935 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
937 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
939 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
947 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
950 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
953 struct tagged_tu_seen tts;
955 tts.next = tagged_tu_seen_base;
958 tagged_tu_seen_base = &tts;
960 if (DECL_NAME (s1) != NULL)
961 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
962 if (DECL_NAME (s1) == DECL_NAME (s2))
965 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
969 needs_warning = true;
971 if (TREE_CODE (s1) == FIELD_DECL
972 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
973 DECL_FIELD_BIT_OFFSET (s2)) != 1)
979 tagged_tu_seen_base = tts.next;
983 return needs_warning ? 2 : 1;
988 struct tagged_tu_seen tts;
990 tts.next = tagged_tu_seen_base;
993 tagged_tu_seen_base = &tts;
995 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
997 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1000 if (TREE_CODE (s1) != TREE_CODE (s2)
1001 || DECL_NAME (s1) != DECL_NAME (s2))
1003 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
1007 needs_warning = true;
1009 if (TREE_CODE (s1) == FIELD_DECL
1010 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1011 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1014 tagged_tu_seen_base = tts.next;
1017 return needs_warning ? 2 : 1;
1025 /* Return 1 if two function types F1 and F2 are compatible.
1026 If either type specifies no argument types,
1027 the other must specify a fixed number of self-promoting arg types.
1028 Otherwise, if one type specifies only the number of arguments,
1029 the other must specify that number of self-promoting arg types.
1030 Otherwise, the argument types must match. */
1033 function_types_compatible_p (tree f1, tree f2)
1036 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1041 ret1 = TREE_TYPE (f1);
1042 ret2 = TREE_TYPE (f2);
1044 /* 'volatile' qualifiers on a function's return type used to mean
1045 the function is noreturn. */
1046 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1047 pedwarn ("function return types not compatible due to %<volatile%>");
1048 if (TYPE_VOLATILE (ret1))
1049 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1050 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1051 if (TYPE_VOLATILE (ret2))
1052 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1053 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1054 val = comptypes (ret1, ret2);
1058 args1 = TYPE_ARG_TYPES (f1);
1059 args2 = TYPE_ARG_TYPES (f2);
1061 /* An unspecified parmlist matches any specified parmlist
1062 whose argument types don't need default promotions. */
1066 if (!self_promoting_args_p (args2))
1068 /* If one of these types comes from a non-prototype fn definition,
1069 compare that with the other type's arglist.
1070 If they don't match, ask for a warning (but no error). */
1071 if (TYPE_ACTUAL_ARG_TYPES (f1)
1072 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1078 if (!self_promoting_args_p (args1))
1080 if (TYPE_ACTUAL_ARG_TYPES (f2)
1081 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1086 /* Both types have argument lists: compare them and propagate results. */
1087 val1 = type_lists_compatible_p (args1, args2);
1088 return val1 != 1 ? val1 : val;
1091 /* Check two lists of types for compatibility,
1092 returning 0 for incompatible, 1 for compatible,
1093 or 2 for compatible with warning. */
1096 type_lists_compatible_p (tree args1, tree args2)
1098 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1104 tree a1, mv1, a2, mv2;
1105 if (args1 == 0 && args2 == 0)
1107 /* If one list is shorter than the other,
1108 they fail to match. */
1109 if (args1 == 0 || args2 == 0)
1111 mv1 = a1 = TREE_VALUE (args1);
1112 mv2 = a2 = TREE_VALUE (args2);
1113 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1114 mv1 = TYPE_MAIN_VARIANT (mv1);
1115 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1116 mv2 = TYPE_MAIN_VARIANT (mv2);
1117 /* A null pointer instead of a type
1118 means there is supposed to be an argument
1119 but nothing is specified about what type it has.
1120 So match anything that self-promotes. */
1123 if (c_type_promotes_to (a2) != a2)
1128 if (c_type_promotes_to (a1) != a1)
1131 /* If one of the lists has an error marker, ignore this arg. */
1132 else if (TREE_CODE (a1) == ERROR_MARK
1133 || TREE_CODE (a2) == ERROR_MARK)
1135 else if (!(newval = comptypes (mv1, mv2)))
1137 /* Allow wait (union {union wait *u; int *i} *)
1138 and wait (union wait *) to be compatible. */
1139 if (TREE_CODE (a1) == UNION_TYPE
1140 && (TYPE_NAME (a1) == 0
1141 || TYPE_TRANSPARENT_UNION (a1))
1142 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1143 && tree_int_cst_equal (TYPE_SIZE (a1),
1147 for (memb = TYPE_FIELDS (a1);
1148 memb; memb = TREE_CHAIN (memb))
1150 tree mv3 = TREE_TYPE (memb);
1151 if (mv3 && mv3 != error_mark_node
1152 && TREE_CODE (mv3) != ARRAY_TYPE)
1153 mv3 = TYPE_MAIN_VARIANT (mv3);
1154 if (comptypes (mv3, mv2))
1160 else if (TREE_CODE (a2) == UNION_TYPE
1161 && (TYPE_NAME (a2) == 0
1162 || TYPE_TRANSPARENT_UNION (a2))
1163 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1164 && tree_int_cst_equal (TYPE_SIZE (a2),
1168 for (memb = TYPE_FIELDS (a2);
1169 memb; memb = TREE_CHAIN (memb))
1171 tree mv3 = TREE_TYPE (memb);
1172 if (mv3 && mv3 != error_mark_node
1173 && TREE_CODE (mv3) != ARRAY_TYPE)
1174 mv3 = TYPE_MAIN_VARIANT (mv3);
1175 if (comptypes (mv3, mv1))
1185 /* comptypes said ok, but record if it said to warn. */
1189 args1 = TREE_CHAIN (args1);
1190 args2 = TREE_CHAIN (args2);
1194 /* Compute the size to increment a pointer by. */
1197 c_size_in_bytes (tree type)
1199 enum tree_code code = TREE_CODE (type);
1201 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1202 return size_one_node;
1204 if (!COMPLETE_OR_VOID_TYPE_P (type))
1206 error ("arithmetic on pointer to an incomplete type");
1207 return size_one_node;
1210 /* Convert in case a char is more than one unit. */
1211 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1212 size_int (TYPE_PRECISION (char_type_node)
1216 /* Return either DECL or its known constant value (if it has one). */
1219 decl_constant_value (tree decl)
1221 if (/* Don't change a variable array bound or initial value to a constant
1222 in a place where a variable is invalid. Note that DECL_INITIAL
1223 isn't valid for a PARM_DECL. */
1224 current_function_decl != 0
1225 && TREE_CODE (decl) != PARM_DECL
1226 && !TREE_THIS_VOLATILE (decl)
1227 && TREE_READONLY (decl)
1228 && DECL_INITIAL (decl) != 0
1229 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1230 /* This is invalid if initial value is not constant.
1231 If it has either a function call, a memory reference,
1232 or a variable, then re-evaluating it could give different results. */
1233 && TREE_CONSTANT (DECL_INITIAL (decl))
1234 /* Check for cases where this is sub-optimal, even though valid. */
1235 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1236 return DECL_INITIAL (decl);
1240 /* Return either DECL or its known constant value (if it has one), but
1241 return DECL if pedantic or DECL has mode BLKmode. This is for
1242 bug-compatibility with the old behavior of decl_constant_value
1243 (before GCC 3.0); every use of this function is a bug and it should
1244 be removed before GCC 3.1. It is not appropriate to use pedantic
1245 in a way that affects optimization, and BLKmode is probably not the
1246 right test for avoiding misoptimizations either. */
1249 decl_constant_value_for_broken_optimization (tree decl)
1251 if (pedantic || DECL_MODE (decl) == BLKmode)
1254 return decl_constant_value (decl);
1258 /* Perform the default conversion of arrays and functions to pointers.
1259 Return the result of converting EXP. For any other expression, just
1263 default_function_array_conversion (tree exp)
1266 tree type = TREE_TYPE (exp);
1267 enum tree_code code = TREE_CODE (type);
1270 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1273 Do not use STRIP_NOPS here! It will remove conversions from pointer
1274 to integer and cause infinite recursion. */
1276 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1277 || (TREE_CODE (exp) == NOP_EXPR
1278 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1280 if (TREE_CODE (exp) == NON_LVALUE_EXPR)
1282 exp = TREE_OPERAND (exp, 0);
1285 if (TREE_NO_WARNING (orig_exp))
1286 TREE_NO_WARNING (exp) = 1;
1288 if (code == FUNCTION_TYPE)
1290 return build_unary_op (ADDR_EXPR, exp, 0);
1292 if (code == ARRAY_TYPE)
1295 tree restype = TREE_TYPE (type);
1301 if (REFERENCE_CLASS_P (exp) || DECL_P (exp))
1303 constp = TREE_READONLY (exp);
1304 volatilep = TREE_THIS_VOLATILE (exp);
1307 if (TYPE_QUALS (type) || constp || volatilep)
1309 = c_build_qualified_type (restype,
1311 | (constp * TYPE_QUAL_CONST)
1312 | (volatilep * TYPE_QUAL_VOLATILE));
1314 if (TREE_CODE (exp) == INDIRECT_REF)
1315 return convert (build_pointer_type (restype),
1316 TREE_OPERAND (exp, 0));
1318 if (TREE_CODE (exp) == COMPOUND_EXPR)
1320 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1321 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1322 TREE_OPERAND (exp, 0), op1);
1325 lvalue_array_p = !not_lvalue && lvalue_p (exp);
1326 if (!flag_isoc99 && !lvalue_array_p)
1328 /* Before C99, non-lvalue arrays do not decay to pointers.
1329 Normally, using such an array would be invalid; but it can
1330 be used correctly inside sizeof or as a statement expression.
1331 Thus, do not give an error here; an error will result later. */
1335 ptrtype = build_pointer_type (restype);
1337 if (TREE_CODE (exp) == VAR_DECL)
1339 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1340 ADDR_EXPR because it's the best way of representing what
1341 happens in C when we take the address of an array and place
1342 it in a pointer to the element type. */
1343 adr = build1 (ADDR_EXPR, ptrtype, exp);
1344 if (!c_mark_addressable (exp))
1345 return error_mark_node;
1346 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1349 /* This way is better for a COMPONENT_REF since it can
1350 simplify the offset for a component. */
1351 adr = build_unary_op (ADDR_EXPR, exp, 1);
1352 return convert (ptrtype, adr);
1357 /* Perform default promotions for C data used in expressions.
1358 Arrays and functions are converted to pointers;
1359 enumeral types or short or char, to int.
1360 In addition, manifest constants symbols are replaced by their values. */
1363 default_conversion (tree exp)
1366 tree type = TREE_TYPE (exp);
1367 enum tree_code code = TREE_CODE (type);
1369 if (code == FUNCTION_TYPE || code == ARRAY_TYPE)
1370 return default_function_array_conversion (exp);
1372 /* Constants can be used directly unless they're not loadable. */
1373 if (TREE_CODE (exp) == CONST_DECL)
1374 exp = DECL_INITIAL (exp);
1376 /* Replace a nonvolatile const static variable with its value unless
1377 it is an array, in which case we must be sure that taking the
1378 address of the array produces consistent results. */
1379 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1381 exp = decl_constant_value_for_broken_optimization (exp);
1382 type = TREE_TYPE (exp);
1385 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1388 Do not use STRIP_NOPS here! It will remove conversions from pointer
1389 to integer and cause infinite recursion. */
1391 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1392 || (TREE_CODE (exp) == NOP_EXPR
1393 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1394 exp = TREE_OPERAND (exp, 0);
1396 if (TREE_NO_WARNING (orig_exp))
1397 TREE_NO_WARNING (exp) = 1;
1399 /* Normally convert enums to int,
1400 but convert wide enums to something wider. */
1401 if (code == ENUMERAL_TYPE)
1403 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1404 TYPE_PRECISION (integer_type_node)),
1405 ((TYPE_PRECISION (type)
1406 >= TYPE_PRECISION (integer_type_node))
1407 && TYPE_UNSIGNED (type)));
1409 return convert (type, exp);
1412 if (TREE_CODE (exp) == COMPONENT_REF
1413 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1414 /* If it's thinner than an int, promote it like a
1415 c_promoting_integer_type_p, otherwise leave it alone. */
1416 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1417 TYPE_PRECISION (integer_type_node)))
1418 return convert (integer_type_node, exp);
1420 if (c_promoting_integer_type_p (type))
1422 /* Preserve unsignedness if not really getting any wider. */
1423 if (TYPE_UNSIGNED (type)
1424 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1425 return convert (unsigned_type_node, exp);
1427 return convert (integer_type_node, exp);
1430 if (code == VOID_TYPE)
1432 error ("void value not ignored as it ought to be");
1433 return error_mark_node;
1438 /* Look up COMPONENT in a structure or union DECL.
1440 If the component name is not found, returns NULL_TREE. Otherwise,
1441 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1442 stepping down the chain to the component, which is in the last
1443 TREE_VALUE of the list. Normally the list is of length one, but if
1444 the component is embedded within (nested) anonymous structures or
1445 unions, the list steps down the chain to the component. */
1448 lookup_field (tree decl, tree component)
1450 tree type = TREE_TYPE (decl);
1453 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1454 to the field elements. Use a binary search on this array to quickly
1455 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1456 will always be set for structures which have many elements. */
1458 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1461 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1463 field = TYPE_FIELDS (type);
1465 top = TYPE_LANG_SPECIFIC (type)->s->len;
1466 while (top - bot > 1)
1468 half = (top - bot + 1) >> 1;
1469 field = field_array[bot+half];
1471 if (DECL_NAME (field) == NULL_TREE)
1473 /* Step through all anon unions in linear fashion. */
1474 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1476 field = field_array[bot++];
1477 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1478 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1480 tree anon = lookup_field (field, component);
1483 return tree_cons (NULL_TREE, field, anon);
1487 /* Entire record is only anon unions. */
1491 /* Restart the binary search, with new lower bound. */
1495 if (DECL_NAME (field) == component)
1497 if (DECL_NAME (field) < component)
1503 if (DECL_NAME (field_array[bot]) == component)
1504 field = field_array[bot];
1505 else if (DECL_NAME (field) != component)
1510 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1512 if (DECL_NAME (field) == NULL_TREE
1513 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1514 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1516 tree anon = lookup_field (field, component);
1519 return tree_cons (NULL_TREE, field, anon);
1522 if (DECL_NAME (field) == component)
1526 if (field == NULL_TREE)
1530 return tree_cons (NULL_TREE, field, NULL_TREE);
1533 /* Make an expression to refer to the COMPONENT field of
1534 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1537 build_component_ref (tree datum, tree component)
1539 tree type = TREE_TYPE (datum);
1540 enum tree_code code = TREE_CODE (type);
1544 if (!objc_is_public (datum, component))
1545 return error_mark_node;
1547 /* See if there is a field or component with name COMPONENT. */
1549 if (code == RECORD_TYPE || code == UNION_TYPE)
1551 if (!COMPLETE_TYPE_P (type))
1553 c_incomplete_type_error (NULL_TREE, type);
1554 return error_mark_node;
1557 field = lookup_field (datum, component);
1561 error ("%qT has no member named %qs", type,
1562 IDENTIFIER_POINTER (component));
1563 return error_mark_node;
1566 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1567 This might be better solved in future the way the C++ front
1568 end does it - by giving the anonymous entities each a
1569 separate name and type, and then have build_component_ref
1570 recursively call itself. We can't do that here. */
1573 tree subdatum = TREE_VALUE (field);
1575 if (TREE_TYPE (subdatum) == error_mark_node)
1576 return error_mark_node;
1578 ref = build3 (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum,
1580 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1581 TREE_READONLY (ref) = 1;
1582 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1583 TREE_THIS_VOLATILE (ref) = 1;
1585 if (TREE_DEPRECATED (subdatum))
1586 warn_deprecated_use (subdatum);
1590 field = TREE_CHAIN (field);
1596 else if (code != ERROR_MARK)
1597 error ("request for member %qs in something not a structure or union",
1598 IDENTIFIER_POINTER (component));
1600 return error_mark_node;
1603 /* Given an expression PTR for a pointer, return an expression
1604 for the value pointed to.
1605 ERRORSTRING is the name of the operator to appear in error messages. */
1608 build_indirect_ref (tree ptr, const char *errorstring)
1610 tree pointer = default_conversion (ptr);
1611 tree type = TREE_TYPE (pointer);
1613 if (TREE_CODE (type) == POINTER_TYPE)
1615 if (TREE_CODE (pointer) == ADDR_EXPR
1616 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1617 == TREE_TYPE (type)))
1618 return TREE_OPERAND (pointer, 0);
1621 tree t = TREE_TYPE (type);
1625 if (TREE_CODE (mvt) != ARRAY_TYPE)
1626 mvt = TYPE_MAIN_VARIANT (mvt);
1627 ref = build1 (INDIRECT_REF, mvt, pointer);
1629 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1631 error ("dereferencing pointer to incomplete type");
1632 return error_mark_node;
1634 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1635 warning ("dereferencing %<void *%> pointer");
1637 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1638 so that we get the proper error message if the result is used
1639 to assign to. Also, &* is supposed to be a no-op.
1640 And ANSI C seems to specify that the type of the result
1641 should be the const type. */
1642 /* A de-reference of a pointer to const is not a const. It is valid
1643 to change it via some other pointer. */
1644 TREE_READONLY (ref) = TYPE_READONLY (t);
1645 TREE_SIDE_EFFECTS (ref)
1646 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1647 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1651 else if (TREE_CODE (pointer) != ERROR_MARK)
1652 error ("invalid type argument of %qs", errorstring);
1653 return error_mark_node;
1656 /* This handles expressions of the form "a[i]", which denotes
1659 This is logically equivalent in C to *(a+i), but we may do it differently.
1660 If A is a variable or a member, we generate a primitive ARRAY_REF.
1661 This avoids forcing the array out of registers, and can work on
1662 arrays that are not lvalues (for example, members of structures returned
1666 build_array_ref (tree array, tree index)
1668 bool swapped = false;
1669 if (TREE_TYPE (array) == error_mark_node
1670 || TREE_TYPE (index) == error_mark_node)
1671 return error_mark_node;
1673 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1674 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1677 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1678 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1680 error ("subscripted value is neither array nor pointer");
1681 return error_mark_node;
1689 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1691 error ("array subscript is not an integer");
1692 return error_mark_node;
1695 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1697 error ("subscripted value is pointer to function");
1698 return error_mark_node;
1701 /* Subscripting with type char is likely to lose on a machine where
1702 chars are signed. So warn on any machine, but optionally. Don't
1703 warn for unsigned char since that type is safe. Don't warn for
1704 signed char because anyone who uses that must have done so
1705 deliberately. ??? Existing practice has also been to warn only
1706 when the char index is syntactically the index, not for
1708 if (warn_char_subscripts && !swapped
1709 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1710 warning ("array subscript has type %<char%>");
1712 /* Apply default promotions *after* noticing character types. */
1713 index = default_conversion (index);
1715 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1717 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1721 /* An array that is indexed by a non-constant
1722 cannot be stored in a register; we must be able to do
1723 address arithmetic on its address.
1724 Likewise an array of elements of variable size. */
1725 if (TREE_CODE (index) != INTEGER_CST
1726 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1727 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1729 if (!c_mark_addressable (array))
1730 return error_mark_node;
1732 /* An array that is indexed by a constant value which is not within
1733 the array bounds cannot be stored in a register either; because we
1734 would get a crash in store_bit_field/extract_bit_field when trying
1735 to access a non-existent part of the register. */
1736 if (TREE_CODE (index) == INTEGER_CST
1737 && TYPE_DOMAIN (TREE_TYPE (array))
1738 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1740 if (!c_mark_addressable (array))
1741 return error_mark_node;
1747 while (TREE_CODE (foo) == COMPONENT_REF)
1748 foo = TREE_OPERAND (foo, 0);
1749 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1750 pedwarn ("ISO C forbids subscripting %<register%> array");
1751 else if (!flag_isoc99 && !lvalue_p (foo))
1752 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1755 type = TREE_TYPE (TREE_TYPE (array));
1756 if (TREE_CODE (type) != ARRAY_TYPE)
1757 type = TYPE_MAIN_VARIANT (type);
1758 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
1759 /* Array ref is const/volatile if the array elements are
1760 or if the array is. */
1761 TREE_READONLY (rval)
1762 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1763 | TREE_READONLY (array));
1764 TREE_SIDE_EFFECTS (rval)
1765 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1766 | TREE_SIDE_EFFECTS (array));
1767 TREE_THIS_VOLATILE (rval)
1768 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1769 /* This was added by rms on 16 Nov 91.
1770 It fixes vol struct foo *a; a->elts[1]
1771 in an inline function.
1772 Hope it doesn't break something else. */
1773 | TREE_THIS_VOLATILE (array));
1774 return require_complete_type (fold (rval));
1778 tree ar = default_conversion (array);
1780 if (ar == error_mark_node)
1783 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
1784 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
1786 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
1791 /* Build an external reference to identifier ID. FUN indicates
1792 whether this will be used for a function call. */
1794 build_external_ref (tree id, int fun)
1797 tree decl = lookup_name (id);
1799 /* In Objective-C, an instance variable (ivar) may be preferred to
1800 whatever lookup_name() found. */
1801 decl = objc_lookup_ivar (decl, id);
1803 if (decl && decl != error_mark_node)
1806 /* Implicit function declaration. */
1807 ref = implicitly_declare (id);
1808 else if (decl == error_mark_node)
1809 /* Don't complain about something that's already been
1810 complained about. */
1811 return error_mark_node;
1814 undeclared_variable (id);
1815 return error_mark_node;
1818 if (TREE_TYPE (ref) == error_mark_node)
1819 return error_mark_node;
1821 if (TREE_DEPRECATED (ref))
1822 warn_deprecated_use (ref);
1824 if (!skip_evaluation)
1825 assemble_external (ref);
1826 TREE_USED (ref) = 1;
1828 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
1830 if (!in_sizeof && !in_typeof)
1831 C_DECL_USED (ref) = 1;
1832 else if (DECL_INITIAL (ref) == 0
1833 && DECL_EXTERNAL (ref)
1834 && !TREE_PUBLIC (ref))
1835 record_maybe_used_decl (ref);
1838 if (TREE_CODE (ref) == CONST_DECL)
1840 ref = DECL_INITIAL (ref);
1841 TREE_CONSTANT (ref) = 1;
1842 TREE_INVARIANT (ref) = 1;
1844 else if (current_function_decl != 0
1845 && !DECL_FILE_SCOPE_P (current_function_decl)
1846 && (TREE_CODE (ref) == VAR_DECL
1847 || TREE_CODE (ref) == PARM_DECL
1848 || TREE_CODE (ref) == FUNCTION_DECL))
1850 tree context = decl_function_context (ref);
1852 if (context != 0 && context != current_function_decl)
1853 DECL_NONLOCAL (ref) = 1;
1859 /* Record details of decls possibly used inside sizeof or typeof. */
1860 struct maybe_used_decl
1864 /* The level seen at (in_sizeof + in_typeof). */
1866 /* The next one at this level or above, or NULL. */
1867 struct maybe_used_decl *next;
1870 static struct maybe_used_decl *maybe_used_decls;
1872 /* Record that DECL, an undefined static function reference seen
1873 inside sizeof or typeof, might be used if the operand of sizeof is
1874 a VLA type or the operand of typeof is a variably modified
1878 record_maybe_used_decl (tree decl)
1880 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
1882 t->level = in_sizeof + in_typeof;
1883 t->next = maybe_used_decls;
1884 maybe_used_decls = t;
1887 /* Pop the stack of decls possibly used inside sizeof or typeof. If
1888 USED is false, just discard them. If it is true, mark them used
1889 (if no longer inside sizeof or typeof) or move them to the next
1890 level up (if still inside sizeof or typeof). */
1893 pop_maybe_used (bool used)
1895 struct maybe_used_decl *p = maybe_used_decls;
1896 int cur_level = in_sizeof + in_typeof;
1897 while (p && p->level > cur_level)
1902 C_DECL_USED (p->decl) = 1;
1904 p->level = cur_level;
1908 if (!used || cur_level == 0)
1909 maybe_used_decls = p;
1912 /* Return the result of sizeof applied to EXPR. */
1915 c_expr_sizeof_expr (struct c_expr expr)
1918 if (expr.value == error_mark_node)
1920 ret.value = error_mark_node;
1921 ret.original_code = ERROR_MARK;
1922 pop_maybe_used (false);
1926 ret.value = c_sizeof (TREE_TYPE (expr.value));
1927 ret.original_code = ERROR_MARK;
1928 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
1933 /* Return the result of sizeof applied to T, a structure for the type
1934 name passed to sizeof (rather than the type itself). */
1937 c_expr_sizeof_type (struct c_type_name *t)
1941 type = groktypename (t);
1942 ret.value = c_sizeof (type);
1943 ret.original_code = ERROR_MARK;
1944 pop_maybe_used (C_TYPE_VARIABLE_SIZE (type));
1948 /* Build a function call to function FUNCTION with parameters PARAMS.
1949 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1950 TREE_VALUE of each node is a parameter-expression.
1951 FUNCTION's data type may be a function type or a pointer-to-function. */
1954 build_function_call (tree function, tree params)
1956 tree fntype, fundecl = 0;
1957 tree coerced_params;
1958 tree name = NULL_TREE, result;
1961 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1962 STRIP_TYPE_NOPS (function);
1964 /* Convert anything with function type to a pointer-to-function. */
1965 if (TREE_CODE (function) == FUNCTION_DECL)
1967 name = DECL_NAME (function);
1969 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1970 (because calling an inline function does not mean the function
1971 needs to be separately compiled). */
1972 fntype = build_type_variant (TREE_TYPE (function),
1973 TREE_READONLY (function),
1974 TREE_THIS_VOLATILE (function));
1976 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1979 function = default_conversion (function);
1981 fntype = TREE_TYPE (function);
1983 if (TREE_CODE (fntype) == ERROR_MARK)
1984 return error_mark_node;
1986 if (!(TREE_CODE (fntype) == POINTER_TYPE
1987 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1989 error ("called object %qE is not a function", function);
1990 return error_mark_node;
1993 if (fundecl && TREE_THIS_VOLATILE (fundecl))
1994 current_function_returns_abnormally = 1;
1996 /* fntype now gets the type of function pointed to. */
1997 fntype = TREE_TYPE (fntype);
1999 /* Check that the function is called through a compatible prototype.
2000 If it is not, replace the call by a trap, wrapped up in a compound
2001 expression if necessary. This has the nice side-effect to prevent
2002 the tree-inliner from generating invalid assignment trees which may
2003 blow up in the RTL expander later.
2005 ??? This doesn't work for Objective-C because objc_comptypes
2006 refuses to compare function prototypes, yet the compiler appears
2007 to build calls that are flagged as invalid by C's comptypes. */
2008 if (!c_dialect_objc ()
2009 && TREE_CODE (function) == NOP_EXPR
2010 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2011 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2012 && !comptypes (fntype, TREE_TYPE (tem)))
2014 tree return_type = TREE_TYPE (fntype);
2015 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2018 /* This situation leads to run-time undefined behavior. We can't,
2019 therefore, simply error unless we can prove that all possible
2020 executions of the program must execute the code. */
2021 warning ("function called through a non-compatible type");
2023 /* We can, however, treat "undefined" any way we please.
2024 Call abort to encourage the user to fix the program. */
2025 inform ("if this code is reached, the program will abort");
2027 if (VOID_TYPE_P (return_type))
2033 if (AGGREGATE_TYPE_P (return_type))
2034 rhs = build_compound_literal (return_type,
2035 build_constructor (return_type,
2038 rhs = fold (build1 (NOP_EXPR, return_type, integer_zero_node));
2040 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2044 /* Convert the parameters to the types declared in the
2045 function prototype, or apply default promotions. */
2048 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2050 if (coerced_params == error_mark_node)
2051 return error_mark_node;
2053 /* Check that the arguments to the function are valid. */
2055 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params);
2057 result = build3 (CALL_EXPR, TREE_TYPE (fntype),
2058 function, coerced_params, NULL_TREE);
2059 TREE_SIDE_EFFECTS (result) = 1;
2061 if (require_constant_value)
2063 result = fold_initializer (result);
2065 if (TREE_CONSTANT (result)
2066 && (name == NULL_TREE
2067 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2068 pedwarn_init ("initializer element is not constant");
2071 result = fold (result);
2073 if (VOID_TYPE_P (TREE_TYPE (result)))
2075 return require_complete_type (result);
2078 /* Convert the argument expressions in the list VALUES
2079 to the types in the list TYPELIST. The result is a list of converted
2080 argument expressions, unless there are too few arguments in which
2081 case it is error_mark_node.
2083 If TYPELIST is exhausted, or when an element has NULL as its type,
2084 perform the default conversions.
2086 PARMLIST is the chain of parm decls for the function being called.
2087 It may be 0, if that info is not available.
2088 It is used only for generating error messages.
2090 FUNCTION is a tree for the called function. It is used only for
2091 error messages, where it is formatted with %qE.
2093 This is also where warnings about wrong number of args are generated.
2095 Both VALUES and the returned value are chains of TREE_LIST nodes
2096 with the elements of the list in the TREE_VALUE slots of those nodes. */
2099 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2101 tree typetail, valtail;
2106 /* Change pointer to function to the function itself for
2108 if (TREE_CODE (function) == ADDR_EXPR
2109 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2110 function = TREE_OPERAND (function, 0);
2112 /* Handle an ObjC selector specially for diagnostics. */
2113 selector = objc_message_selector ();
2115 /* Scan the given expressions and types, producing individual
2116 converted arguments and pushing them on RESULT in reverse order. */
2118 for (valtail = values, typetail = typelist, parmnum = 0;
2120 valtail = TREE_CHAIN (valtail), parmnum++)
2122 tree type = typetail ? TREE_VALUE (typetail) : 0;
2123 tree val = TREE_VALUE (valtail);
2124 tree rname = function;
2125 int argnum = parmnum + 1;
2127 if (type == void_type_node)
2129 error ("too many arguments to function %qE", function);
2133 if (selector && argnum > 2)
2139 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
2140 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
2141 to convert automatically to a pointer. */
2142 if (TREE_CODE (val) == NON_LVALUE_EXPR)
2143 val = TREE_OPERAND (val, 0);
2145 val = default_function_array_conversion (val);
2147 val = require_complete_type (val);
2151 /* Formal parm type is specified by a function prototype. */
2154 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2156 error ("type of formal parameter %d is incomplete", parmnum + 1);
2161 /* Optionally warn about conversions that
2162 differ from the default conversions. */
2163 if (warn_conversion || warn_traditional)
2165 unsigned int formal_prec = TYPE_PRECISION (type);
2167 if (INTEGRAL_TYPE_P (type)
2168 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2169 warning ("passing argument %d of %qE as integer "
2170 "rather than floating due to prototype",
2172 if (INTEGRAL_TYPE_P (type)
2173 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2174 warning ("passing argument %d of %qE as integer "
2175 "rather than complex due to prototype",
2177 else if (TREE_CODE (type) == COMPLEX_TYPE
2178 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2179 warning ("passing argument %d of %qE as complex "
2180 "rather than floating due to prototype",
2182 else if (TREE_CODE (type) == REAL_TYPE
2183 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2184 warning ("passing argument %d of %qE as floating "
2185 "rather than integer due to prototype",
2187 else if (TREE_CODE (type) == COMPLEX_TYPE
2188 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2189 warning ("passing argument %d of %qE as complex "
2190 "rather than integer due to prototype",
2192 else if (TREE_CODE (type) == REAL_TYPE
2193 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2194 warning ("passing argument %d of %qE as floating "
2195 "rather than complex due to prototype",
2197 /* ??? At some point, messages should be written about
2198 conversions between complex types, but that's too messy
2200 else if (TREE_CODE (type) == REAL_TYPE
2201 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2203 /* Warn if any argument is passed as `float',
2204 since without a prototype it would be `double'. */
2205 if (formal_prec == TYPE_PRECISION (float_type_node))
2206 warning ("passing argument %d of %qE as %<float%> "
2207 "rather than %<double%> due to prototype",
2210 /* Detect integer changing in width or signedness.
2211 These warnings are only activated with
2212 -Wconversion, not with -Wtraditional. */
2213 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2214 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2216 tree would_have_been = default_conversion (val);
2217 tree type1 = TREE_TYPE (would_have_been);
2219 if (TREE_CODE (type) == ENUMERAL_TYPE
2220 && (TYPE_MAIN_VARIANT (type)
2221 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2222 /* No warning if function asks for enum
2223 and the actual arg is that enum type. */
2225 else if (formal_prec != TYPE_PRECISION (type1))
2226 warning ("passing argument %d of %qE with different "
2227 "width due to prototype", argnum, rname);
2228 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2230 /* Don't complain if the formal parameter type
2231 is an enum, because we can't tell now whether
2232 the value was an enum--even the same enum. */
2233 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2235 else if (TREE_CODE (val) == INTEGER_CST
2236 && int_fits_type_p (val, type))
2237 /* Change in signedness doesn't matter
2238 if a constant value is unaffected. */
2240 /* Likewise for a constant in a NOP_EXPR. */
2241 else if (TREE_CODE (val) == NOP_EXPR
2242 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
2243 && int_fits_type_p (TREE_OPERAND (val, 0), type))
2245 /* If the value is extended from a narrower
2246 unsigned type, it doesn't matter whether we
2247 pass it as signed or unsigned; the value
2248 certainly is the same either way. */
2249 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2250 && TYPE_UNSIGNED (TREE_TYPE (val)))
2252 else if (TYPE_UNSIGNED (type))
2253 warning ("passing argument %d of %qE as unsigned "
2254 "due to prototype", argnum, rname);
2256 warning ("passing argument %d of %qE as signed "
2257 "due to prototype", argnum, rname);
2261 parmval = convert_for_assignment (type, val, ic_argpass,
2265 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2266 && INTEGRAL_TYPE_P (type)
2267 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2268 parmval = default_conversion (parmval);
2270 result = tree_cons (NULL_TREE, parmval, result);
2272 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2273 && (TYPE_PRECISION (TREE_TYPE (val))
2274 < TYPE_PRECISION (double_type_node)))
2275 /* Convert `float' to `double'. */
2276 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2278 /* Convert `short' and `char' to full-size `int'. */
2279 result = tree_cons (NULL_TREE, default_conversion (val), result);
2282 typetail = TREE_CHAIN (typetail);
2285 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2287 error ("too few arguments to function %qE", function);
2288 return error_mark_node;
2291 return nreverse (result);
2294 /* This is the entry point used by the parser
2295 for binary operators in the input.
2296 In addition to constructing the expression,
2297 we check for operands that were written with other binary operators
2298 in a way that is likely to confuse the user. */
2301 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2304 struct c_expr result;
2306 enum tree_code code1 = arg1.original_code;
2307 enum tree_code code2 = arg2.original_code;
2309 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2310 result.original_code = code;
2312 if (TREE_CODE (result.value) == ERROR_MARK)
2315 /* Check for cases such as x+y<<z which users are likely
2317 if (warn_parentheses)
2319 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2321 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2322 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2323 warning ("suggest parentheses around + or - inside shift");
2326 if (code == TRUTH_ORIF_EXPR)
2328 if (code1 == TRUTH_ANDIF_EXPR
2329 || code2 == TRUTH_ANDIF_EXPR)
2330 warning ("suggest parentheses around && within ||");
2333 if (code == BIT_IOR_EXPR)
2335 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2336 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2337 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2338 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2339 warning ("suggest parentheses around arithmetic in operand of |");
2340 /* Check cases like x|y==z */
2341 if (TREE_CODE_CLASS (code1) == tcc_comparison
2342 || TREE_CODE_CLASS (code2) == tcc_comparison)
2343 warning ("suggest parentheses around comparison in operand of |");
2346 if (code == BIT_XOR_EXPR)
2348 if (code1 == BIT_AND_EXPR
2349 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2350 || code2 == BIT_AND_EXPR
2351 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2352 warning ("suggest parentheses around arithmetic in operand of ^");
2353 /* Check cases like x^y==z */
2354 if (TREE_CODE_CLASS (code1) == tcc_comparison
2355 || TREE_CODE_CLASS (code2) == tcc_comparison)
2356 warning ("suggest parentheses around comparison in operand of ^");
2359 if (code == BIT_AND_EXPR)
2361 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2362 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2363 warning ("suggest parentheses around + or - in operand of &");
2364 /* Check cases like x&y==z */
2365 if (TREE_CODE_CLASS (code1) == tcc_comparison
2366 || TREE_CODE_CLASS (code2) == tcc_comparison)
2367 warning ("suggest parentheses around comparison in operand of &");
2369 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2370 if (TREE_CODE_CLASS (code) == tcc_comparison
2371 && (TREE_CODE_CLASS (code1) == tcc_comparison
2372 || TREE_CODE_CLASS (code2) == tcc_comparison))
2373 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
2377 unsigned_conversion_warning (result.value, arg1.value);
2378 unsigned_conversion_warning (result.value, arg2.value);
2379 overflow_warning (result.value);
2384 /* Return a tree for the difference of pointers OP0 and OP1.
2385 The resulting tree has type int. */
2388 pointer_diff (tree op0, tree op1)
2390 tree restype = ptrdiff_type_node;
2392 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2393 tree con0, con1, lit0, lit1;
2394 tree orig_op1 = op1;
2396 if (pedantic || warn_pointer_arith)
2398 if (TREE_CODE (target_type) == VOID_TYPE)
2399 pedwarn ("pointer of type %<void *%> used in subtraction");
2400 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2401 pedwarn ("pointer to a function used in subtraction");
2404 /* If the conversion to ptrdiff_type does anything like widening or
2405 converting a partial to an integral mode, we get a convert_expression
2406 that is in the way to do any simplifications.
2407 (fold-const.c doesn't know that the extra bits won't be needed.
2408 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2409 different mode in place.)
2410 So first try to find a common term here 'by hand'; we want to cover
2411 at least the cases that occur in legal static initializers. */
2412 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2413 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2415 if (TREE_CODE (con0) == PLUS_EXPR)
2417 lit0 = TREE_OPERAND (con0, 1);
2418 con0 = TREE_OPERAND (con0, 0);
2421 lit0 = integer_zero_node;
2423 if (TREE_CODE (con1) == PLUS_EXPR)
2425 lit1 = TREE_OPERAND (con1, 1);
2426 con1 = TREE_OPERAND (con1, 0);
2429 lit1 = integer_zero_node;
2431 if (operand_equal_p (con0, con1, 0))
2438 /* First do the subtraction as integers;
2439 then drop through to build the divide operator.
2440 Do not do default conversions on the minus operator
2441 in case restype is a short type. */
2443 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2444 convert (restype, op1), 0);
2445 /* This generates an error if op1 is pointer to incomplete type. */
2446 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2447 error ("arithmetic on pointer to an incomplete type");
2449 /* This generates an error if op0 is pointer to incomplete type. */
2450 op1 = c_size_in_bytes (target_type);
2452 /* Divide by the size, in easiest possible way. */
2453 return fold (build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)));
2456 /* Construct and perhaps optimize a tree representation
2457 for a unary operation. CODE, a tree_code, specifies the operation
2458 and XARG is the operand.
2459 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2460 the default promotions (such as from short to int).
2461 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2462 allows non-lvalues; this is only used to handle conversion of non-lvalue
2463 arrays to pointers in C99. */
2466 build_unary_op (enum tree_code code, tree xarg, int flag)
2468 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2471 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2473 int noconvert = flag;
2475 if (typecode == ERROR_MARK)
2476 return error_mark_node;
2477 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2478 typecode = INTEGER_TYPE;
2483 /* This is used for unary plus, because a CONVERT_EXPR
2484 is enough to prevent anybody from looking inside for
2485 associativity, but won't generate any code. */
2486 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2487 || typecode == COMPLEX_TYPE
2488 || typecode == VECTOR_TYPE))
2490 error ("wrong type argument to unary plus");
2491 return error_mark_node;
2493 else if (!noconvert)
2494 arg = default_conversion (arg);
2495 arg = non_lvalue (arg);
2499 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2500 || typecode == COMPLEX_TYPE
2501 || typecode == VECTOR_TYPE))
2503 error ("wrong type argument to unary minus");
2504 return error_mark_node;
2506 else if (!noconvert)
2507 arg = default_conversion (arg);
2511 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2514 arg = default_conversion (arg);
2516 else if (typecode == COMPLEX_TYPE)
2520 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2522 arg = default_conversion (arg);
2526 error ("wrong type argument to bit-complement");
2527 return error_mark_node;
2532 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2534 error ("wrong type argument to abs");
2535 return error_mark_node;
2537 else if (!noconvert)
2538 arg = default_conversion (arg);
2542 /* Conjugating a real value is a no-op, but allow it anyway. */
2543 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2544 || typecode == COMPLEX_TYPE))
2546 error ("wrong type argument to conjugation");
2547 return error_mark_node;
2549 else if (!noconvert)
2550 arg = default_conversion (arg);
2553 case TRUTH_NOT_EXPR:
2554 if (typecode != INTEGER_TYPE
2555 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2556 && typecode != COMPLEX_TYPE
2557 /* These will convert to a pointer. */
2558 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2560 error ("wrong type argument to unary exclamation mark");
2561 return error_mark_node;
2563 arg = lang_hooks.truthvalue_conversion (arg);
2564 return invert_truthvalue (arg);
2570 if (TREE_CODE (arg) == COMPLEX_CST)
2571 return TREE_REALPART (arg);
2572 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2573 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2578 if (TREE_CODE (arg) == COMPLEX_CST)
2579 return TREE_IMAGPART (arg);
2580 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2581 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2583 return convert (TREE_TYPE (arg), integer_zero_node);
2585 case PREINCREMENT_EXPR:
2586 case POSTINCREMENT_EXPR:
2587 case PREDECREMENT_EXPR:
2588 case POSTDECREMENT_EXPR:
2590 /* Increment or decrement the real part of the value,
2591 and don't change the imaginary part. */
2592 if (typecode == COMPLEX_TYPE)
2597 pedwarn ("ISO C does not support %<++%> and %<--%>"
2598 " on complex types");
2600 arg = stabilize_reference (arg);
2601 real = build_unary_op (REALPART_EXPR, arg, 1);
2602 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2603 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2604 build_unary_op (code, real, 1), imag);
2607 /* Report invalid types. */
2609 if (typecode != POINTER_TYPE
2610 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2612 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2613 error ("wrong type argument to increment");
2615 error ("wrong type argument to decrement");
2617 return error_mark_node;
2622 tree result_type = TREE_TYPE (arg);
2624 arg = get_unwidened (arg, 0);
2625 argtype = TREE_TYPE (arg);
2627 /* Compute the increment. */
2629 if (typecode == POINTER_TYPE)
2631 /* If pointer target is an undefined struct,
2632 we just cannot know how to do the arithmetic. */
2633 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2635 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2636 error ("increment of pointer to unknown structure");
2638 error ("decrement of pointer to unknown structure");
2640 else if ((pedantic || warn_pointer_arith)
2641 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2642 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2644 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2645 pedwarn ("wrong type argument to increment");
2647 pedwarn ("wrong type argument to decrement");
2650 inc = c_size_in_bytes (TREE_TYPE (result_type));
2653 inc = integer_one_node;
2655 inc = convert (argtype, inc);
2657 /* Complain about anything else that is not a true lvalue. */
2658 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2659 || code == POSTINCREMENT_EXPR)
2662 return error_mark_node;
2664 /* Report a read-only lvalue. */
2665 if (TREE_READONLY (arg))
2666 readonly_error (arg,
2667 ((code == PREINCREMENT_EXPR
2668 || code == POSTINCREMENT_EXPR)
2669 ? lv_increment : lv_decrement));
2671 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2672 val = boolean_increment (code, arg);
2674 val = build2 (code, TREE_TYPE (arg), arg, inc);
2675 TREE_SIDE_EFFECTS (val) = 1;
2676 val = convert (result_type, val);
2677 if (TREE_CODE (val) != code)
2678 TREE_NO_WARNING (val) = 1;
2683 /* Note that this operation never does default_conversion. */
2685 /* Let &* cancel out to simplify resulting code. */
2686 if (TREE_CODE (arg) == INDIRECT_REF)
2688 /* Don't let this be an lvalue. */
2689 if (lvalue_p (TREE_OPERAND (arg, 0)))
2690 return non_lvalue (TREE_OPERAND (arg, 0));
2691 return TREE_OPERAND (arg, 0);
2694 /* For &x[y], return x+y */
2695 if (TREE_CODE (arg) == ARRAY_REF)
2697 if (!c_mark_addressable (TREE_OPERAND (arg, 0)))
2698 return error_mark_node;
2699 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2700 TREE_OPERAND (arg, 1), 1);
2703 /* Anything not already handled and not a true memory reference
2704 or a non-lvalue array is an error. */
2705 else if (typecode != FUNCTION_TYPE && !flag
2706 && !lvalue_or_else (arg, lv_addressof))
2707 return error_mark_node;
2709 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2710 argtype = TREE_TYPE (arg);
2712 /* If the lvalue is const or volatile, merge that into the type
2713 to which the address will point. Note that you can't get a
2714 restricted pointer by taking the address of something, so we
2715 only have to deal with `const' and `volatile' here. */
2716 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
2717 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2718 argtype = c_build_type_variant (argtype,
2719 TREE_READONLY (arg),
2720 TREE_THIS_VOLATILE (arg));
2722 if (!c_mark_addressable (arg))
2723 return error_mark_node;
2725 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
2726 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
2728 argtype = build_pointer_type (argtype);
2730 /* ??? Cope with user tricks that amount to offsetof. Delete this
2731 when we have proper support for integer constant expressions. */
2732 val = get_base_address (arg);
2733 if (val && TREE_CODE (val) == INDIRECT_REF
2734 && integer_zerop (TREE_OPERAND (val, 0)))
2735 return fold_convert (argtype, fold_offsetof (arg));
2737 val = build1 (ADDR_EXPR, argtype, arg);
2739 if (TREE_CODE (arg) == COMPOUND_LITERAL_EXPR)
2740 TREE_INVARIANT (val) = TREE_CONSTANT (val) = 1;
2749 argtype = TREE_TYPE (arg);
2750 val = build1 (code, argtype, arg);
2751 return require_constant_value ? fold_initializer (val) : fold (val);
2754 /* Return nonzero if REF is an lvalue valid for this language.
2755 Lvalues can be assigned, unless their type has TYPE_READONLY.
2756 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2761 enum tree_code code = TREE_CODE (ref);
2768 return lvalue_p (TREE_OPERAND (ref, 0));
2770 case COMPOUND_LITERAL_EXPR:
2780 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2781 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2784 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2791 /* Give an error for storing in something that is 'const'. */
2794 readonly_error (tree arg, enum lvalue_use use)
2796 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2797 /* Using this macro rather than (for example) arrays of messages
2798 ensures that all the format strings are checked at compile
2800 #define READONLY_MSG(A, I, D) (use == lv_assign \
2802 : (use == lv_increment ? (I) : (D)))
2803 if (TREE_CODE (arg) == COMPONENT_REF)
2805 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2806 readonly_error (TREE_OPERAND (arg, 0), use);
2808 error (READONLY_MSG (N_("assignment of read-only member %qs"),
2809 N_("increment of read-only member %qs"),
2810 N_("decrement of read-only member %qs")),
2811 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
2813 else if (TREE_CODE (arg) == VAR_DECL)
2814 error (READONLY_MSG (N_("assignment of read-only variable %qs"),
2815 N_("increment of read-only variable %qs"),
2816 N_("decrement of read-only variable %qs")),
2817 IDENTIFIER_POINTER (DECL_NAME (arg)));
2819 error (READONLY_MSG (N_("assignment of read-only location"),
2820 N_("increment of read-only location"),
2821 N_("decrement of read-only location")));
2824 /* Mark EXP saying that we need to be able to take the
2825 address of it; it should not be allocated in a register.
2826 Returns true if successful. */
2829 c_mark_addressable (tree exp)
2834 switch (TREE_CODE (x))
2837 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2840 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2844 /* ... fall through ... */
2850 x = TREE_OPERAND (x, 0);
2853 case COMPOUND_LITERAL_EXPR:
2855 TREE_ADDRESSABLE (x) = 1;
2862 if (C_DECL_REGISTER (x)
2863 && DECL_NONLOCAL (x))
2865 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2868 ("global register variable %qD used in nested function", x);
2871 pedwarn ("register variable %qD used in nested function", x);
2873 else if (C_DECL_REGISTER (x))
2875 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2876 error ("address of global register variable %qD requested", x);
2878 error ("address of register variable %qD requested", x);
2884 TREE_ADDRESSABLE (x) = 1;
2891 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2894 build_conditional_expr (tree ifexp, tree op1, tree op2)
2898 enum tree_code code1;
2899 enum tree_code code2;
2900 tree result_type = NULL;
2901 tree orig_op1 = op1, orig_op2 = op2;
2903 ifexp = lang_hooks.truthvalue_conversion (default_conversion (ifexp));
2905 /* Promote both alternatives. */
2907 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2908 op1 = default_conversion (op1);
2909 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2910 op2 = default_conversion (op2);
2912 if (TREE_CODE (ifexp) == ERROR_MARK
2913 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2914 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2915 return error_mark_node;
2917 type1 = TREE_TYPE (op1);
2918 code1 = TREE_CODE (type1);
2919 type2 = TREE_TYPE (op2);
2920 code2 = TREE_CODE (type2);
2922 /* C90 does not permit non-lvalue arrays in conditional expressions.
2923 In C99 they will be pointers by now. */
2924 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2926 error ("non-lvalue array in conditional expression");
2927 return error_mark_node;
2930 /* Quickly detect the usual case where op1 and op2 have the same type
2932 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
2935 result_type = type1;
2937 result_type = TYPE_MAIN_VARIANT (type1);
2939 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
2940 || code1 == COMPLEX_TYPE)
2941 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
2942 || code2 == COMPLEX_TYPE))
2944 result_type = c_common_type (type1, type2);
2946 /* If -Wsign-compare, warn here if type1 and type2 have
2947 different signedness. We'll promote the signed to unsigned
2948 and later code won't know it used to be different.
2949 Do this check on the original types, so that explicit casts
2950 will be considered, but default promotions won't. */
2951 if (warn_sign_compare && !skip_evaluation)
2953 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
2954 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
2956 if (unsigned_op1 ^ unsigned_op2)
2958 /* Do not warn if the result type is signed, since the
2959 signed type will only be chosen if it can represent
2960 all the values of the unsigned type. */
2961 if (!TYPE_UNSIGNED (result_type))
2963 /* Do not warn if the signed quantity is an unsuffixed
2964 integer literal (or some static constant expression
2965 involving such literals) and it is non-negative. */
2966 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
2967 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
2970 warning ("signed and unsigned type in conditional expression");
2974 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
2976 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
2977 pedwarn ("ISO C forbids conditional expr with only one void side");
2978 result_type = void_type_node;
2980 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
2982 if (comp_target_types (type1, type2, 1))
2983 result_type = common_pointer_type (type1, type2);
2984 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
2985 && TREE_CODE (orig_op1) != NOP_EXPR)
2986 result_type = qualify_type (type2, type1);
2987 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
2988 && TREE_CODE (orig_op2) != NOP_EXPR)
2989 result_type = qualify_type (type1, type2);
2990 else if (VOID_TYPE_P (TREE_TYPE (type1)))
2992 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
2993 pedwarn ("ISO C forbids conditional expr between "
2994 "%<void *%> and function pointer");
2995 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
2996 TREE_TYPE (type2)));
2998 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3000 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3001 pedwarn ("ISO C forbids conditional expr between "
3002 "%<void *%> and function pointer");
3003 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3004 TREE_TYPE (type1)));
3008 pedwarn ("pointer type mismatch in conditional expression");
3009 result_type = build_pointer_type (void_type_node);
3012 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3014 if (!integer_zerop (op2))
3015 pedwarn ("pointer/integer type mismatch in conditional expression");
3018 op2 = null_pointer_node;
3020 result_type = type1;
3022 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3024 if (!integer_zerop (op1))
3025 pedwarn ("pointer/integer type mismatch in conditional expression");
3028 op1 = null_pointer_node;
3030 result_type = type2;
3035 if (flag_cond_mismatch)
3036 result_type = void_type_node;
3039 error ("type mismatch in conditional expression");
3040 return error_mark_node;
3044 /* Merge const and volatile flags of the incoming types. */
3046 = build_type_variant (result_type,
3047 TREE_READONLY (op1) || TREE_READONLY (op2),
3048 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3050 if (result_type != TREE_TYPE (op1))
3051 op1 = convert_and_check (result_type, op1);
3052 if (result_type != TREE_TYPE (op2))
3053 op2 = convert_and_check (result_type, op2);
3055 if (TREE_CODE (ifexp) == INTEGER_CST)
3056 return non_lvalue (integer_zerop (ifexp) ? op2 : op1);
3058 return fold (build3 (COND_EXPR, result_type, ifexp, op1, op2));
3061 /* Return a compound expression that performs two expressions and
3062 returns the value of the second of them. */
3065 build_compound_expr (tree expr1, tree expr2)
3067 /* Convert arrays and functions to pointers. */
3068 expr2 = default_function_array_conversion (expr2);
3070 if (!TREE_SIDE_EFFECTS (expr1))
3072 /* The left-hand operand of a comma expression is like an expression
3073 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3074 any side-effects, unless it was explicitly cast to (void). */
3075 if (warn_unused_value
3076 && !(TREE_CODE (expr1) == CONVERT_EXPR
3077 && VOID_TYPE_P (TREE_TYPE (expr1))))
3078 warning ("left-hand operand of comma expression has no effect");
3081 /* With -Wunused, we should also warn if the left-hand operand does have
3082 side-effects, but computes a value which is not used. For example, in
3083 `foo() + bar(), baz()' the result of the `+' operator is not used,
3084 so we should issue a warning. */
3085 else if (warn_unused_value)
3086 warn_if_unused_value (expr1, input_location);
3088 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3091 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3094 build_c_cast (tree type, tree expr)
3098 if (type == error_mark_node || expr == error_mark_node)
3099 return error_mark_node;
3101 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3102 only in <protocol> qualifications. But when constructing cast expressions,
3103 the protocols do matter and must be kept around. */
3104 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3105 return build1 (NOP_EXPR, type, expr);
3107 type = TYPE_MAIN_VARIANT (type);
3109 if (TREE_CODE (type) == ARRAY_TYPE)
3111 error ("cast specifies array type");
3112 return error_mark_node;
3115 if (TREE_CODE (type) == FUNCTION_TYPE)
3117 error ("cast specifies function type");
3118 return error_mark_node;
3121 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3125 if (TREE_CODE (type) == RECORD_TYPE
3126 || TREE_CODE (type) == UNION_TYPE)
3127 pedwarn ("ISO C forbids casting nonscalar to the same type");
3130 else if (TREE_CODE (type) == UNION_TYPE)
3133 value = default_function_array_conversion (value);
3135 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3136 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3137 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3145 pedwarn ("ISO C forbids casts to union type");
3146 t = digest_init (type,
3147 build_constructor (type,
3148 build_tree_list (field, value)),
3150 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3151 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3154 error ("cast to union type from type not present in union");
3155 return error_mark_node;
3161 /* If casting to void, avoid the error that would come
3162 from default_conversion in the case of a non-lvalue array. */
3163 if (type == void_type_node)
3164 return build1 (CONVERT_EXPR, type, value);
3166 /* Convert functions and arrays to pointers,
3167 but don't convert any other types. */
3168 value = default_function_array_conversion (value);
3169 otype = TREE_TYPE (value);
3171 /* Optionally warn about potentially worrisome casts. */
3174 && TREE_CODE (type) == POINTER_TYPE
3175 && TREE_CODE (otype) == POINTER_TYPE)
3177 tree in_type = type;
3178 tree in_otype = otype;
3182 /* Check that the qualifiers on IN_TYPE are a superset of
3183 the qualifiers of IN_OTYPE. The outermost level of
3184 POINTER_TYPE nodes is uninteresting and we stop as soon
3185 as we hit a non-POINTER_TYPE node on either type. */
3188 in_otype = TREE_TYPE (in_otype);
3189 in_type = TREE_TYPE (in_type);
3191 /* GNU C allows cv-qualified function types. 'const'
3192 means the function is very pure, 'volatile' means it
3193 can't return. We need to warn when such qualifiers
3194 are added, not when they're taken away. */
3195 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3196 && TREE_CODE (in_type) == FUNCTION_TYPE)
3197 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3199 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3201 while (TREE_CODE (in_type) == POINTER_TYPE
3202 && TREE_CODE (in_otype) == POINTER_TYPE);
3205 warning ("cast adds new qualifiers to function type");
3208 /* There are qualifiers present in IN_OTYPE that are not
3209 present in IN_TYPE. */
3210 warning ("cast discards qualifiers from pointer target type");
3213 /* Warn about possible alignment problems. */
3214 if (STRICT_ALIGNMENT && warn_cast_align
3215 && TREE_CODE (type) == POINTER_TYPE
3216 && TREE_CODE (otype) == POINTER_TYPE
3217 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3218 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3219 /* Don't warn about opaque types, where the actual alignment
3220 restriction is unknown. */
3221 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3222 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3223 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3224 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3225 warning ("cast increases required alignment of target type");
3227 if (TREE_CODE (type) == INTEGER_TYPE
3228 && TREE_CODE (otype) == POINTER_TYPE
3229 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3230 && !TREE_CONSTANT (value))
3231 warning ("cast from pointer to integer of different size");
3233 if (warn_bad_function_cast
3234 && TREE_CODE (value) == CALL_EXPR
3235 && TREE_CODE (type) != TREE_CODE (otype))
3236 warning ("cast from function call of type %qT to non-matching "
3237 "type %qT", otype, type);
3239 if (TREE_CODE (type) == POINTER_TYPE
3240 && TREE_CODE (otype) == INTEGER_TYPE
3241 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3242 /* Don't warn about converting any constant. */
3243 && !TREE_CONSTANT (value))
3244 warning ("cast to pointer from integer of different size");
3246 if (TREE_CODE (type) == POINTER_TYPE
3247 && TREE_CODE (otype) == POINTER_TYPE
3248 && TREE_CODE (expr) == ADDR_EXPR
3249 && DECL_P (TREE_OPERAND (expr, 0))
3250 && flag_strict_aliasing && warn_strict_aliasing
3251 && !VOID_TYPE_P (TREE_TYPE (type)))
3253 /* Casting the address of a decl to non void pointer. Warn
3254 if the cast breaks type based aliasing. */
3255 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3256 warning ("type-punning to incomplete type might break strict-aliasing rules");
3259 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3260 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3262 if (!alias_sets_conflict_p (set1, set2))
3263 warning ("dereferencing type-punned pointer will break strict-aliasing rules");
3264 else if (warn_strict_aliasing > 1
3265 && !alias_sets_might_conflict_p (set1, set2))
3266 warning ("dereferencing type-punned pointer might break strict-aliasing rules");
3270 /* If pedantic, warn for conversions between function and object
3271 pointer types, except for converting a null pointer constant
3272 to function pointer type. */
3274 && TREE_CODE (type) == POINTER_TYPE
3275 && TREE_CODE (otype) == POINTER_TYPE
3276 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3277 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3278 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3281 && TREE_CODE (type) == POINTER_TYPE
3282 && TREE_CODE (otype) == POINTER_TYPE
3283 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3284 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3285 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3286 && TREE_CODE (expr) != NOP_EXPR))
3287 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3290 value = convert (type, value);
3292 /* Ignore any integer overflow caused by the cast. */
3293 if (TREE_CODE (value) == INTEGER_CST)
3295 if (EXPR_P (ovalue))
3296 /* If OVALUE had overflow set, then so will VALUE, so it
3297 is safe to overwrite. */
3298 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3300 TREE_OVERFLOW (value) = 0;
3302 if (CONSTANT_CLASS_P (ovalue))
3303 /* Similarly, constant_overflow cannot have become
3305 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3309 /* Don't let a cast be an lvalue. */
3311 value = non_lvalue (value);
3316 /* Interpret a cast of expression EXPR to type TYPE. */
3318 c_cast_expr (struct c_type_name *type_name, tree expr)
3321 int saved_wsp = warn_strict_prototypes;
3323 /* This avoids warnings about unprototyped casts on
3324 integers. E.g. "#define SIG_DFL (void(*)())0". */
3325 if (TREE_CODE (expr) == INTEGER_CST)
3326 warn_strict_prototypes = 0;
3327 type = groktypename (type_name);
3328 warn_strict_prototypes = saved_wsp;
3330 return build_c_cast (type, expr);
3334 /* Build an assignment expression of lvalue LHS from value RHS.
3335 MODIFYCODE is the code for a binary operator that we use
3336 to combine the old value of LHS with RHS to get the new value.
3337 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3340 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3344 tree lhstype = TREE_TYPE (lhs);
3345 tree olhstype = lhstype;
3347 /* Types that aren't fully specified cannot be used in assignments. */
3348 lhs = require_complete_type (lhs);
3350 /* Avoid duplicate error messages from operands that had errors. */
3351 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3352 return error_mark_node;
3354 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3355 /* Do not use STRIP_NOPS here. We do not want an enumerator
3356 whose value is 0 to count as a null pointer constant. */
3357 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3358 rhs = TREE_OPERAND (rhs, 0);
3362 /* If a binary op has been requested, combine the old LHS value with the RHS
3363 producing the value we should actually store into the LHS. */
3365 if (modifycode != NOP_EXPR)
3367 lhs = stabilize_reference (lhs);
3368 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3371 if (!lvalue_or_else (lhs, lv_assign))
3372 return error_mark_node;
3374 /* Give an error for storing in something that is 'const'. */
3376 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3377 || ((TREE_CODE (lhstype) == RECORD_TYPE
3378 || TREE_CODE (lhstype) == UNION_TYPE)
3379 && C_TYPE_FIELDS_READONLY (lhstype)))
3380 readonly_error (lhs, lv_assign);
3382 /* If storing into a structure or union member,
3383 it has probably been given type `int'.
3384 Compute the type that would go with
3385 the actual amount of storage the member occupies. */
3387 if (TREE_CODE (lhs) == COMPONENT_REF
3388 && (TREE_CODE (lhstype) == INTEGER_TYPE
3389 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3390 || TREE_CODE (lhstype) == REAL_TYPE
3391 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3392 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3394 /* If storing in a field that is in actuality a short or narrower than one,
3395 we must store in the field in its actual type. */
3397 if (lhstype != TREE_TYPE (lhs))
3399 lhs = copy_node (lhs);
3400 TREE_TYPE (lhs) = lhstype;
3403 /* Convert new value to destination type. */
3405 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3406 NULL_TREE, NULL_TREE, 0);
3407 if (TREE_CODE (newrhs) == ERROR_MARK)
3408 return error_mark_node;
3410 /* Scan operands. */
3412 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3413 TREE_SIDE_EFFECTS (result) = 1;
3415 /* If we got the LHS in a different type for storing in,
3416 convert the result back to the nominal type of LHS
3417 so that the value we return always has the same type
3418 as the LHS argument. */
3420 if (olhstype == TREE_TYPE (result))
3422 return convert_for_assignment (olhstype, result, ic_assign,
3423 NULL_TREE, NULL_TREE, 0);
3426 /* Convert value RHS to type TYPE as preparation for an assignment
3427 to an lvalue of type TYPE.
3428 The real work of conversion is done by `convert'.
3429 The purpose of this function is to generate error messages
3430 for assignments that are not allowed in C.
3431 ERRTYPE says whether it is argument passing, assignment,
3432 initialization or return.
3434 FUNCTION is a tree for the function being called.
3435 PARMNUM is the number of the argument, for printing in error messages. */
3438 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3439 tree fundecl, tree function, int parmnum)
3441 enum tree_code codel = TREE_CODE (type);
3443 enum tree_code coder;
3444 tree rname = NULL_TREE;
3446 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3449 /* Change pointer to function to the function itself for
3451 if (TREE_CODE (function) == ADDR_EXPR
3452 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3453 function = TREE_OPERAND (function, 0);
3455 /* Handle an ObjC selector specially for diagnostics. */
3456 selector = objc_message_selector ();
3458 if (selector && parmnum > 2)
3465 /* This macro is used to emit diagnostics to ensure that all format
3466 strings are complete sentences, visible to gettext and checked at
3468 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3473 pedwarn (AR, parmnum, rname); \
3475 case ic_argpass_nonproto: \
3476 warning (AR, parmnum, rname); \
3488 gcc_unreachable (); \
3492 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3493 /* Do not use STRIP_NOPS here. We do not want an enumerator
3494 whose value is 0 to count as a null pointer constant. */
3495 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3496 rhs = TREE_OPERAND (rhs, 0);
3498 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3499 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3500 rhs = default_conversion (rhs);
3501 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3502 rhs = decl_constant_value_for_broken_optimization (rhs);
3504 rhstype = TREE_TYPE (rhs);
3505 coder = TREE_CODE (rhstype);
3507 if (coder == ERROR_MARK)
3508 return error_mark_node;
3510 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3512 overflow_warning (rhs);
3513 /* Check for Objective-C protocols. This will automatically
3514 issue a warning if there are protocol violations. No need to
3515 use the return value. */
3516 if (c_dialect_objc ())
3517 objc_comptypes (type, rhstype, 0);
3521 if (coder == VOID_TYPE)
3523 /* Except for passing an argument to an unprototyped function,
3524 this is a constraint violation. When passing an argument to
3525 an unprototyped function, it is compile-time undefined;
3526 making it a constraint in that case was rejected in
3528 error ("void value not ignored as it ought to be");
3529 return error_mark_node;
3531 /* A type converts to a reference to it.
3532 This code doesn't fully support references, it's just for the
3533 special case of va_start and va_copy. */
3534 if (codel == REFERENCE_TYPE
3535 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3537 if (!lvalue_p (rhs))
3539 error ("cannot pass rvalue to reference parameter");
3540 return error_mark_node;
3542 if (!c_mark_addressable (rhs))
3543 return error_mark_node;
3544 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3546 /* We already know that these two types are compatible, but they
3547 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3548 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3549 likely to be va_list, a typedef to __builtin_va_list, which
3550 is different enough that it will cause problems later. */
3551 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3552 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3554 rhs = build1 (NOP_EXPR, type, rhs);
3557 /* Some types can interconvert without explicit casts. */
3558 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3559 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3560 return convert (type, rhs);
3561 /* Arithmetic types all interconvert, and enum is treated like int. */
3562 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3563 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3564 || codel == BOOLEAN_TYPE)
3565 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3566 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3567 || coder == BOOLEAN_TYPE))
3568 return convert_and_check (type, rhs);
3570 /* Conversion to a transparent union from its member types.
3571 This applies only to function arguments. */
3572 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3573 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3576 tree marginal_memb_type = 0;
3578 for (memb_types = TYPE_FIELDS (type); memb_types;
3579 memb_types = TREE_CHAIN (memb_types))
3581 tree memb_type = TREE_TYPE (memb_types);
3583 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3584 TYPE_MAIN_VARIANT (rhstype)))
3587 if (TREE_CODE (memb_type) != POINTER_TYPE)
3590 if (coder == POINTER_TYPE)
3592 tree ttl = TREE_TYPE (memb_type);
3593 tree ttr = TREE_TYPE (rhstype);
3595 /* Any non-function converts to a [const][volatile] void *
3596 and vice versa; otherwise, targets must be the same.
3597 Meanwhile, the lhs target must have all the qualifiers of
3599 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3600 || comp_target_types (memb_type, rhstype, 0))
3602 /* If this type won't generate any warnings, use it. */
3603 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3604 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3605 && TREE_CODE (ttl) == FUNCTION_TYPE)
3606 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3607 == TYPE_QUALS (ttr))
3608 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3609 == TYPE_QUALS (ttl))))
3612 /* Keep looking for a better type, but remember this one. */
3613 if (!marginal_memb_type)
3614 marginal_memb_type = memb_type;
3618 /* Can convert integer zero to any pointer type. */
3619 if (integer_zerop (rhs)
3620 || (TREE_CODE (rhs) == NOP_EXPR
3621 && integer_zerop (TREE_OPERAND (rhs, 0))))
3623 rhs = null_pointer_node;
3628 if (memb_types || marginal_memb_type)
3632 /* We have only a marginally acceptable member type;
3633 it needs a warning. */
3634 tree ttl = TREE_TYPE (marginal_memb_type);
3635 tree ttr = TREE_TYPE (rhstype);
3637 /* Const and volatile mean something different for function
3638 types, so the usual warnings are not appropriate. */
3639 if (TREE_CODE (ttr) == FUNCTION_TYPE
3640 && TREE_CODE (ttl) == FUNCTION_TYPE)
3642 /* Because const and volatile on functions are
3643 restrictions that say the function will not do
3644 certain things, it is okay to use a const or volatile
3645 function where an ordinary one is wanted, but not
3647 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3648 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE "
3649 "makes qualified function "
3650 "pointer from unqualified"),
3651 N_("assignment makes qualified "
3652 "function pointer from "
3654 N_("initialization makes qualified "
3655 "function pointer from "
3657 N_("return makes qualified function "
3658 "pointer from unqualified"));
3660 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3661 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3662 "qualifiers from pointer target type"),
3663 N_("assignment discards qualifiers "
3664 "from pointer target type"),
3665 N_("initialization discards qualifiers "
3666 "from pointer target type"),
3667 N_("return discards qualifiers from "
3668 "pointer target type"));
3671 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3672 pedwarn ("ISO C prohibits argument conversion to union type");
3674 return build1 (NOP_EXPR, type, rhs);
3678 /* Conversions among pointers */
3679 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3680 && (coder == codel))
3682 tree ttl = TREE_TYPE (type);
3683 tree ttr = TREE_TYPE (rhstype);
3686 bool is_opaque_pointer;
3687 int target_cmp = 0; /* Cache comp_target_types () result. */
3689 if (TREE_CODE (mvl) != ARRAY_TYPE)
3690 mvl = TYPE_MAIN_VARIANT (mvl);
3691 if (TREE_CODE (mvr) != ARRAY_TYPE)
3692 mvr = TYPE_MAIN_VARIANT (mvr);
3693 /* Opaque pointers are treated like void pointers. */
3694 is_opaque_pointer = (targetm.vector_opaque_p (type)
3695 || targetm.vector_opaque_p (rhstype))
3696 && TREE_CODE (ttl) == VECTOR_TYPE
3697 && TREE_CODE (ttr) == VECTOR_TYPE;
3699 /* Any non-function converts to a [const][volatile] void *
3700 and vice versa; otherwise, targets must be the same.
3701 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3702 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3703 || (target_cmp = comp_target_types (type, rhstype, 0))
3704 || is_opaque_pointer
3705 || (c_common_unsigned_type (mvl)
3706 == c_common_unsigned_type (mvr)))
3709 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3712 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3713 which are not ANSI null ptr constants. */
3714 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3715 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3716 WARN_FOR_ASSIGNMENT (N_("ISO C forbids passing argument %d of "
3717 "%qE between function pointer "
3719 N_("ISO C forbids assignment between "
3720 "function pointer and %<void *%>"),
3721 N_("ISO C forbids initialization between "
3722 "function pointer and %<void *%>"),
3723 N_("ISO C forbids return between function "
3724 "pointer and %<void *%>"));
3725 /* Const and volatile mean something different for function types,
3726 so the usual warnings are not appropriate. */
3727 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3728 && TREE_CODE (ttl) != FUNCTION_TYPE)
3730 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3731 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3732 "qualifiers from pointer target type"),
3733 N_("assignment discards qualifiers "
3734 "from pointer target type"),
3735 N_("initialization discards qualifiers "
3736 "from pointer target type"),
3737 N_("return discards qualifiers from "
3738 "pointer target type"));
3739 /* If this is not a case of ignoring a mismatch in signedness,
3741 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3744 /* If there is a mismatch, do warn. */
3745 else if (warn_pointer_sign)
3746 WARN_FOR_ASSIGNMENT (N_("pointer targets in passing argument "
3747 "%d of %qE differ in signedness"),
3748 N_("pointer targets in assignment "
3749 "differ in signedness"),
3750 N_("pointer targets in initialization "
3751 "differ in signedness"),
3752 N_("pointer targets in return differ "
3755 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3756 && TREE_CODE (ttr) == FUNCTION_TYPE)
3758 /* Because const and volatile on functions are restrictions
3759 that say the function will not do certain things,
3760 it is okay to use a const or volatile function
3761 where an ordinary one is wanted, but not vice-versa. */
3762 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3763 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3764 "qualified function pointer "
3765 "from unqualified"),
3766 N_("assignment makes qualified function "
3767 "pointer from unqualified"),
3768 N_("initialization makes qualified "
3769 "function pointer from unqualified"),
3770 N_("return makes qualified function "
3771 "pointer from unqualified"));
3775 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE from "
3776 "incompatible pointer type"),
3777 N_("assignment from incompatible pointer type"),
3778 N_("initialization from incompatible "
3780 N_("return from incompatible pointer type"));
3781 return convert (type, rhs);
3783 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3785 /* ??? This should not be an error when inlining calls to
3786 unprototyped functions. */
3787 error ("invalid use of non-lvalue array");
3788 return error_mark_node;
3790 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3792 /* An explicit constant 0 can convert to a pointer,
3793 or one that results from arithmetic, even including
3794 a cast to integer type. */
3795 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3797 !(TREE_CODE (rhs) == NOP_EXPR
3798 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3799 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3800 && integer_zerop (TREE_OPERAND (rhs, 0))))
3801 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3802 "pointer from integer without a cast"),
3803 N_("assignment makes pointer from integer "
3805 N_("initialization makes pointer from "
3806 "integer without a cast"),
3807 N_("return makes pointer from integer "
3810 return convert (type, rhs);
3812 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3814 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes integer "
3815 "from pointer without a cast"),
3816 N_("assignment makes integer from pointer "
3818 N_("initialization makes integer from pointer "
3820 N_("return makes integer from pointer "
3822 return convert (type, rhs);
3824 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3825 return convert (type, rhs);
3830 case ic_argpass_nonproto:
3831 /* ??? This should not be an error when inlining calls to
3832 unprototyped functions. */
3833 error ("incompatible type for argument %d of %qE", parmnum, rname);
3836 error ("incompatible types in assignment");
3839 error ("incompatible types in initialization");
3842 error ("incompatible types in return");
3848 return error_mark_node;
3851 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3852 is used for error and waring reporting and indicates which argument
3853 is being processed. */
3856 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3860 /* If FN was prototyped, the value has been converted already
3861 in convert_arguments. */
3862 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3865 type = TREE_TYPE (parm);
3866 ret = convert_for_assignment (type, value,
3867 ic_argpass_nonproto, fn,
3869 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3870 && INTEGRAL_TYPE_P (type)
3871 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3872 ret = default_conversion (ret);
3876 /* If VALUE is a compound expr all of whose expressions are constant, then
3877 return its value. Otherwise, return error_mark_node.
3879 This is for handling COMPOUND_EXPRs as initializer elements
3880 which is allowed with a warning when -pedantic is specified. */
3883 valid_compound_expr_initializer (tree value, tree endtype)
3885 if (TREE_CODE (value) == COMPOUND_EXPR)
3887 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3889 return error_mark_node;
3890 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3893 else if (!initializer_constant_valid_p (value, endtype))
3894 return error_mark_node;
3899 /* Perform appropriate conversions on the initial value of a variable,
3900 store it in the declaration DECL,
3901 and print any error messages that are appropriate.
3902 If the init is invalid, store an ERROR_MARK. */
3905 store_init_value (tree decl, tree init)
3909 /* If variable's type was invalidly declared, just ignore it. */
3911 type = TREE_TYPE (decl);
3912 if (TREE_CODE (type) == ERROR_MARK)
3915 /* Digest the specified initializer into an expression. */
3917 value = digest_init (type, init, true, TREE_STATIC (decl));
3919 /* Store the expression if valid; else report error. */
3921 if (warn_traditional && !in_system_header
3922 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
3923 warning ("traditional C rejects automatic aggregate initialization");
3925 DECL_INITIAL (decl) = value;
3927 /* ANSI wants warnings about out-of-range constant initializers. */
3928 STRIP_TYPE_NOPS (value);
3929 constant_expression_warning (value);
3931 /* Check if we need to set array size from compound literal size. */
3932 if (TREE_CODE (type) == ARRAY_TYPE
3933 && TYPE_DOMAIN (type) == 0
3934 && value != error_mark_node)
3936 tree inside_init = init;
3938 if (TREE_CODE (init) == NON_LVALUE_EXPR)
3939 inside_init = TREE_OPERAND (init, 0);
3940 inside_init = fold (inside_init);
3942 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
3944 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
3946 if (TYPE_DOMAIN (TREE_TYPE (decl)))
3948 /* For int foo[] = (int [3]){1}; we need to set array size
3949 now since later on array initializer will be just the
3950 brace enclosed list of the compound literal. */
3951 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
3953 layout_decl (decl, 0);
3959 /* Methods for storing and printing names for error messages. */
3961 /* Implement a spelling stack that allows components of a name to be pushed
3962 and popped. Each element on the stack is this structure. */
3974 #define SPELLING_STRING 1
3975 #define SPELLING_MEMBER 2
3976 #define SPELLING_BOUNDS 3
3978 static struct spelling *spelling; /* Next stack element (unused). */
3979 static struct spelling *spelling_base; /* Spelling stack base. */
3980 static int spelling_size; /* Size of the spelling stack. */
3982 /* Macros to save and restore the spelling stack around push_... functions.
3983 Alternative to SAVE_SPELLING_STACK. */
3985 #define SPELLING_DEPTH() (spelling - spelling_base)
3986 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
3988 /* Push an element on the spelling stack with type KIND and assign VALUE
3991 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
3993 int depth = SPELLING_DEPTH (); \
3995 if (depth >= spelling_size) \
3997 spelling_size += 10; \
3998 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4000 RESTORE_SPELLING_DEPTH (depth); \
4003 spelling->kind = (KIND); \
4004 spelling->MEMBER = (VALUE); \
4008 /* Push STRING on the stack. Printed literally. */
4011 push_string (const char *string)
4013 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4016 /* Push a member name on the stack. Printed as '.' STRING. */
4019 push_member_name (tree decl)
4021 const char *const string
4022 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4023 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4026 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4029 push_array_bounds (int bounds)
4031 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4034 /* Compute the maximum size in bytes of the printed spelling. */
4037 spelling_length (void)
4042 for (p = spelling_base; p < spelling; p++)
4044 if (p->kind == SPELLING_BOUNDS)
4047 size += strlen (p->u.s) + 1;
4053 /* Print the spelling to BUFFER and return it. */
4056 print_spelling (char *buffer)
4061 for (p = spelling_base; p < spelling; p++)
4062 if (p->kind == SPELLING_BOUNDS)
4064 sprintf (d, "[%d]", p->u.i);
4070 if (p->kind == SPELLING_MEMBER)
4072 for (s = p->u.s; (*d = *s++); d++)
4079 /* Issue an error message for a bad initializer component.
4080 MSGID identifies the message.
4081 The component name is taken from the spelling stack. */
4084 error_init (const char *msgid)
4088 error ("%s", _(msgid));
4089 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4091 error ("(near initialization for %qs)", ofwhat);
4094 /* Issue a pedantic warning for a bad initializer component.
4095 MSGID identifies the message.
4096 The component name is taken from the spelling stack. */
4099 pedwarn_init (const char *msgid)
4103 pedwarn ("%s", _(msgid));
4104 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4106 pedwarn ("(near initialization for %qs)", ofwhat);
4109 /* Issue a warning for a bad initializer component.
4110 MSGID identifies the message.
4111 The component name is taken from the spelling stack. */
4114 warning_init (const char *msgid)
4118 warning ("%s", _(msgid));
4119 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4121 warning ("(near initialization for %qs)", ofwhat);
4124 /* If TYPE is an array type and EXPR is a parenthesized string
4125 constant, warn if pedantic that EXPR is being used to initialize an
4126 object of type TYPE. */
4129 maybe_warn_string_init (tree type, struct c_expr expr)
4132 && TREE_CODE (type) == ARRAY_TYPE
4133 && TREE_CODE (expr.value) == STRING_CST
4134 && expr.original_code != STRING_CST)
4135 pedwarn_init ("array initialized from parenthesized string constant");
4138 /* Digest the parser output INIT as an initializer for type TYPE.
4139 Return a C expression of type TYPE to represent the initial value.
4141 If INIT is a string constant, STRICT_STRING is true if it is
4142 unparenthesized or we should not warn here for it being parenthesized.
4143 For other types of INIT, STRICT_STRING is not used.
4145 REQUIRE_CONSTANT requests an error if non-constant initializers or
4146 elements are seen. */
4149 digest_init (tree type, tree init, bool strict_string, int require_constant)
4151 enum tree_code code = TREE_CODE (type);
4152 tree inside_init = init;
4154 if (type == error_mark_node
4155 || init == error_mark_node
4156 || TREE_TYPE (init) == error_mark_node)
4157 return error_mark_node;
4159 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4160 /* Do not use STRIP_NOPS here. We do not want an enumerator
4161 whose value is 0 to count as a null pointer constant. */
4162 if (TREE_CODE (init) == NON_LVALUE_EXPR)
4163 inside_init = TREE_OPERAND (init, 0);
4165 inside_init = fold (inside_init);
4167 /* Initialization of an array of chars from a string constant
4168 optionally enclosed in braces. */
4170 if (code == ARRAY_TYPE && inside_init
4171 && TREE_CODE (inside_init) == STRING_CST)
4173 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4174 /* Note that an array could be both an array of character type
4175 and an array of wchar_t if wchar_t is signed char or unsigned
4177 bool char_array = (typ1 == char_type_node
4178 || typ1 == signed_char_type_node
4179 || typ1 == unsigned_char_type_node);
4180 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4181 if (char_array || wchar_array)
4185 expr.value = inside_init;
4186 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4187 maybe_warn_string_init (type, expr);
4190 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4193 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4194 TYPE_MAIN_VARIANT (type)))
4197 if (!wchar_array && !char_string)
4199 error_init ("char-array initialized from wide string");
4200 return error_mark_node;
4202 if (char_string && !char_array)
4204 error_init ("wchar_t-array initialized from non-wide string");
4205 return error_mark_node;
4208 TREE_TYPE (inside_init) = type;
4209 if (TYPE_DOMAIN (type) != 0
4210 && TYPE_SIZE (type) != 0
4211 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4212 /* Subtract 1 (or sizeof (wchar_t))
4213 because it's ok to ignore the terminating null char
4214 that is counted in the length of the constant. */
4215 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4216 TREE_STRING_LENGTH (inside_init)
4217 - ((TYPE_PRECISION (typ1)
4218 != TYPE_PRECISION (char_type_node))
4219 ? (TYPE_PRECISION (wchar_type_node)
4222 pedwarn_init ("initializer-string for array of chars is too long");
4226 else if (INTEGRAL_TYPE_P (typ1))
4228 error_init ("array of inappropriate type initialized "
4229 "from string constant");
4230 return error_mark_node;
4234 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4235 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4236 below and handle as a constructor. */
4237 if (code == VECTOR_TYPE
4238 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4239 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4240 && TREE_CONSTANT (inside_init))
4242 if (TREE_CODE (inside_init) == VECTOR_CST
4243 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4244 TYPE_MAIN_VARIANT (type)))
4247 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4251 /* Iterate through elements and check if all constructor
4252 elements are *_CSTs. */
4253 for (link = CONSTRUCTOR_ELTS (inside_init);
4255 link = TREE_CHAIN (link))
4256 if (! CONSTANT_CLASS_P (TREE_VALUE (link)))
4260 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4264 /* Any type can be initialized
4265 from an expression of the same type, optionally with braces. */
4267 if (inside_init && TREE_TYPE (inside_init) != 0
4268 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4269 TYPE_MAIN_VARIANT (type))
4270 || (code == ARRAY_TYPE
4271 && comptypes (TREE_TYPE (inside_init), type))
4272 || (code == VECTOR_TYPE
4273 && comptypes (TREE_TYPE (inside_init), type))
4274 || (code == POINTER_TYPE
4275 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4276 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4278 || (code == POINTER_TYPE
4279 && TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE
4280 && comptypes (TREE_TYPE (inside_init),
4281 TREE_TYPE (type)))))
4283 if (code == POINTER_TYPE)
4285 inside_init = default_function_array_conversion (inside_init);
4287 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4289 error_init ("invalid use of non-lvalue array");
4290 return error_mark_node;
4294 if (code == VECTOR_TYPE)
4295 /* Although the types are compatible, we may require a
4297 inside_init = convert (type, inside_init);
4299 if (require_constant && !flag_isoc99
4300 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4302 /* As an extension, allow initializing objects with static storage
4303 duration with compound literals (which are then treated just as
4304 the brace enclosed list they contain). */
4305 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4306 inside_init = DECL_INITIAL (decl);
4309 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4310 && TREE_CODE (inside_init) != CONSTRUCTOR)
4312 error_init ("array initialized from non-constant array expression");
4313 return error_mark_node;
4316 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4317 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4319 /* Compound expressions can only occur here if -pedantic or
4320 -pedantic-errors is specified. In the later case, we always want
4321 an error. In the former case, we simply want a warning. */
4322 if (require_constant && pedantic
4323 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4326 = valid_compound_expr_initializer (inside_init,
4327 TREE_TYPE (inside_init));
4328 if (inside_init == error_mark_node)
4329 error_init ("initializer element is not constant");
4331 pedwarn_init ("initializer element is not constant");
4332 if (flag_pedantic_errors)
4333 inside_init = error_mark_node;
4335 else if (require_constant
4336 && !initializer_constant_valid_p (inside_init,
4337 TREE_TYPE (inside_init)))
4339 error_init ("initializer element is not constant");
4340 inside_init = error_mark_node;
4346 /* Handle scalar types, including conversions. */
4348 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4349 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4350 || code == VECTOR_TYPE)
4352 /* Note that convert_for_assignment calls default_conversion
4353 for arrays and functions. We must not call it in the
4354 case where inside_init is a null pointer constant. */
4356 = convert_for_assignment (type, init, ic_init,
4357 NULL_TREE, NULL_TREE, 0);
4359 /* Check to see if we have already given an error message. */
4360 if (inside_init == error_mark_node)
4362 else if (require_constant && !TREE_CONSTANT (inside_init))
4364 error_init ("initializer element is not constant");
4365 inside_init = error_mark_node;
4367 else if (require_constant
4368 && !initializer_constant_valid_p (inside_init,
4369 TREE_TYPE (inside_init)))
4371 error_init ("initializer element is not computable at load time");
4372 inside_init = error_mark_node;
4378 /* Come here only for records and arrays. */
4380 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4382 error_init ("variable-sized object may not be initialized");
4383 return error_mark_node;
4386 error_init ("invalid initializer");
4387 return error_mark_node;
4390 /* Handle initializers that use braces. */
4392 /* Type of object we are accumulating a constructor for.
4393 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4394 static tree constructor_type;
4396 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4398 static tree constructor_fields;
4400 /* For an ARRAY_TYPE, this is the specified index
4401 at which to store the next element we get. */
4402 static tree constructor_index;
4404 /* For an ARRAY_TYPE, this is the maximum index. */
4405 static tree constructor_max_index;
4407 /* For a RECORD_TYPE, this is the first field not yet written out. */
4408 static tree constructor_unfilled_fields;
4410 /* For an ARRAY_TYPE, this is the index of the first element
4411 not yet written out. */
4412 static tree constructor_unfilled_index;
4414 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4415 This is so we can generate gaps between fields, when appropriate. */
4416 static tree constructor_bit_index;
4418 /* If we are saving up the elements rather than allocating them,
4419 this is the list of elements so far (in reverse order,
4420 most recent first). */
4421 static tree constructor_elements;
4423 /* 1 if constructor should be incrementally stored into a constructor chain,
4424 0 if all the elements should be kept in AVL tree. */
4425 static int constructor_incremental;
4427 /* 1 if so far this constructor's elements are all compile-time constants. */
4428 static int constructor_constant;
4430 /* 1 if so far this constructor's elements are all valid address constants. */
4431 static int constructor_simple;
4433 /* 1 if this constructor is erroneous so far. */
4434 static int constructor_erroneous;
4436 /* Structure for managing pending initializer elements, organized as an
4441 struct init_node *left, *right;
4442 struct init_node *parent;
4448 /* Tree of pending elements at this constructor level.
4449 These are elements encountered out of order
4450 which belong at places we haven't reached yet in actually
4452 Will never hold tree nodes across GC runs. */
4453 static struct init_node *constructor_pending_elts;
4455 /* The SPELLING_DEPTH of this constructor. */
4456 static int constructor_depth;
4458 /* DECL node for which an initializer is being read.
4459 0 means we are reading a constructor expression
4460 such as (struct foo) {...}. */
4461 static tree constructor_decl;
4463 /* Nonzero if this is an initializer for a top-level decl. */
4464 static int constructor_top_level;
4466 /* Nonzero if there were any member designators in this initializer. */
4467 static int constructor_designated;
4469 /* Nesting depth of designator list. */
4470 static int designator_depth;
4472 /* Nonzero if there were diagnosed errors in this designator list. */
4473 static int designator_errorneous;
4476 /* This stack has a level for each implicit or explicit level of
4477 structuring in the initializer, including the outermost one. It
4478 saves the values of most of the variables above. */
4480 struct constructor_range_stack;
4482 struct constructor_stack
4484 struct constructor_stack *next;
4489 tree unfilled_index;
4490 tree unfilled_fields;
4493 struct init_node *pending_elts;
4496 /* If value nonzero, this value should replace the entire
4497 constructor at this level. */
4498 struct c_expr replacement_value;
4499 struct constructor_range_stack *range_stack;
4509 struct constructor_stack *constructor_stack;
4511 /* This stack represents designators from some range designator up to
4512 the last designator in the list. */
4514 struct constructor_range_stack
4516 struct constructor_range_stack *next, *prev;
4517 struct constructor_stack *stack;
4524 struct constructor_range_stack *constructor_range_stack;
4526 /* This stack records separate initializers that are nested.
4527 Nested initializers can't happen in ANSI C, but GNU C allows them
4528 in cases like { ... (struct foo) { ... } ... }. */
4530 struct initializer_stack
4532 struct initializer_stack *next;
4534 struct constructor_stack *constructor_stack;
4535 struct constructor_range_stack *constructor_range_stack;
4537 struct spelling *spelling;
4538 struct spelling *spelling_base;
4541 char require_constant_value;
4542 char require_constant_elements;
4545 struct initializer_stack *initializer_stack;
4547 /* Prepare to parse and output the initializer for variable DECL. */
4550 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4553 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4555 p->decl = constructor_decl;
4556 p->require_constant_value = require_constant_value;
4557 p->require_constant_elements = require_constant_elements;
4558 p->constructor_stack = constructor_stack;
4559 p->constructor_range_stack = constructor_range_stack;
4560 p->elements = constructor_elements;
4561 p->spelling = spelling;
4562 p->spelling_base = spelling_base;
4563 p->spelling_size = spelling_size;
4564 p->top_level = constructor_top_level;
4565 p->next = initializer_stack;
4566 initializer_stack = p;
4568 constructor_decl = decl;
4569 constructor_designated = 0;
4570 constructor_top_level = top_level;
4572 if (decl != 0 && decl != error_mark_node)
4574 require_constant_value = TREE_STATIC (decl);
4575 require_constant_elements
4576 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4577 /* For a scalar, you can always use any value to initialize,
4578 even within braces. */
4579 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4580 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4581 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4582 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4583 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4587 require_constant_value = 0;
4588 require_constant_elements = 0;
4589 locus = "(anonymous)";
4592 constructor_stack = 0;
4593 constructor_range_stack = 0;
4595 missing_braces_mentioned = 0;
4599 RESTORE_SPELLING_DEPTH (0);
4602 push_string (locus);
4608 struct initializer_stack *p = initializer_stack;
4610 /* Free the whole constructor stack of this initializer. */
4611 while (constructor_stack)
4613 struct constructor_stack *q = constructor_stack;
4614 constructor_stack = q->next;
4618 gcc_assert (!constructor_range_stack);
4620 /* Pop back to the data of the outer initializer (if any). */
4621 free (spelling_base);
4623 constructor_decl = p->decl;
4624 require_constant_value = p->require_constant_value;
4625 require_constant_elements = p->require_constant_elements;
4626 constructor_stack = p->constructor_stack;
4627 constructor_range_stack = p->constructor_range_stack;
4628 constructor_elements = p->elements;
4629 spelling = p->spelling;
4630 spelling_base = p->spelling_base;
4631 spelling_size = p->spelling_size;
4632 constructor_top_level = p->top_level;
4633 initializer_stack = p->next;
4637 /* Call here when we see the initializer is surrounded by braces.
4638 This is instead of a call to push_init_level;
4639 it is matched by a call to pop_init_level.
4641 TYPE is the type to initialize, for a constructor expression.
4642 For an initializer for a decl, TYPE is zero. */
4645 really_start_incremental_init (tree type)
4647 struct constructor_stack *p = XNEW (struct constructor_stack);
4650 type = TREE_TYPE (constructor_decl);
4652 if (targetm.vector_opaque_p (type))
4653 error ("opaque vector types cannot be initialized");
4655 p->type = constructor_type;
4656 p->fields = constructor_fields;
4657 p->index = constructor_index;
4658 p->max_index = constructor_max_index;
4659 p->unfilled_index = constructor_unfilled_index;
4660 p->unfilled_fields = constructor_unfilled_fields;
4661 p->bit_index = constructor_bit_index;
4662 p->elements = constructor_elements;
4663 p->constant = constructor_constant;
4664 p->simple = constructor_simple;
4665 p->erroneous = constructor_erroneous;
4666 p->pending_elts = constructor_pending_elts;
4667 p->depth = constructor_depth;
4668 p->replacement_value.value = 0;
4669 p->replacement_value.original_code = ERROR_MARK;
4673 p->incremental = constructor_incremental;
4674 p->designated = constructor_designated;
4676 constructor_stack = p;
4678 constructor_constant = 1;
4679 constructor_simple = 1;
4680 constructor_depth = SPELLING_DEPTH ();
4681 constructor_elements = 0;
4682 constructor_pending_elts = 0;
4683 constructor_type = type;
4684 constructor_incremental = 1;
4685 constructor_designated = 0;
4686 designator_depth = 0;
4687 designator_errorneous = 0;
4689 if (TREE_CODE (constructor_type) == RECORD_TYPE
4690 || TREE_CODE (constructor_type) == UNION_TYPE)
4692 constructor_fields = TYPE_FIELDS (constructor_type);
4693 /* Skip any nameless bit fields at the beginning. */
4694 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4695 && DECL_NAME (constructor_fields) == 0)
4696 constructor_fields = TREE_CHAIN (constructor_fields);
4698 constructor_unfilled_fields = constructor_fields;
4699 constructor_bit_index = bitsize_zero_node;
4701 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4703 if (TYPE_DOMAIN (constructor_type))
4705 constructor_max_index
4706 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4708 /* Detect non-empty initializations of zero-length arrays. */
4709 if (constructor_max_index == NULL_TREE
4710 && TYPE_SIZE (constructor_type))
4711 constructor_max_index = build_int_cst (NULL_TREE, -1);
4713 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4714 to initialize VLAs will cause a proper error; avoid tree
4715 checking errors as well by setting a safe value. */
4716 if (constructor_max_index
4717 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4718 constructor_max_index = build_int_cst (NULL_TREE, -1);
4721 = convert (bitsizetype,
4722 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4726 constructor_index = bitsize_zero_node;
4727 constructor_max_index = NULL_TREE;
4730 constructor_unfilled_index = constructor_index;
4732 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4734 /* Vectors are like simple fixed-size arrays. */
4735 constructor_max_index =
4736 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4737 constructor_index = convert (bitsizetype, bitsize_zero_node);
4738 constructor_unfilled_index = constructor_index;
4742 /* Handle the case of int x = {5}; */
4743 constructor_fields = constructor_type;
4744 constructor_unfilled_fields = constructor_type;
4748 /* Push down into a subobject, for initialization.
4749 If this is for an explicit set of braces, IMPLICIT is 0.
4750 If it is because the next element belongs at a lower level,
4751 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4754 push_init_level (int implicit)
4756 struct constructor_stack *p;
4757 tree value = NULL_TREE;
4759 /* If we've exhausted any levels that didn't have braces,
4761 while (constructor_stack->implicit)
4763 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4764 || TREE_CODE (constructor_type) == UNION_TYPE)
4765 && constructor_fields == 0)
4766 process_init_element (pop_init_level (1));
4767 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4768 && constructor_max_index
4769 && tree_int_cst_lt (constructor_max_index, constructor_index))
4770 process_init_element (pop_init_level (1));
4775 /* Unless this is an explicit brace, we need to preserve previous
4779 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4780 || TREE_CODE (constructor_type) == UNION_TYPE)
4781 && constructor_fields)
4782 value = find_init_member (constructor_fields);
4783 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4784 value = find_init_member (constructor_index);
4787 p = XNEW (struct constructor_stack);
4788 p->type = constructor_type;
4789 p->fields = constructor_fields;
4790 p->index = constructor_index;
4791 p->max_index = constructor_max_index;
4792 p->unfilled_index = constructor_unfilled_index;
4793 p->unfilled_fields = constructor_unfilled_fields;
4794 p->bit_index = constructor_bit_index;
4795 p->elements = constructor_elements;
4796 p->constant = constructor_constant;
4797 p->simple = constructor_simple;
4798 p->erroneous = constructor_erroneous;
4799 p->pending_elts = constructor_pending_elts;
4800 p->depth = constructor_depth;
4801 p->replacement_value.value = 0;
4802 p->replacement_value.original_code = ERROR_MARK;
4803 p->implicit = implicit;
4805 p->incremental = constructor_incremental;
4806 p->designated = constructor_designated;
4807 p->next = constructor_stack;
4809 constructor_stack = p;
4811 constructor_constant = 1;
4812 constructor_simple = 1;
4813 constructor_depth = SPELLING_DEPTH ();
4814 constructor_elements = 0;
4815 constructor_incremental = 1;
4816 constructor_designated = 0;
4817 constructor_pending_elts = 0;
4820 p->range_stack = constructor_range_stack;
4821 constructor_range_stack = 0;
4822 designator_depth = 0;
4823 designator_errorneous = 0;
4826 /* Don't die if an entire brace-pair level is superfluous
4827 in the containing level. */
4828 if (constructor_type == 0)
4830 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4831 || TREE_CODE (constructor_type) == UNION_TYPE)
4833 /* Don't die if there are extra init elts at the end. */
4834 if (constructor_fields == 0)
4835 constructor_type = 0;
4838 constructor_type = TREE_TYPE (constructor_fields);
4839 push_member_name (constructor_fields);
4840 constructor_depth++;
4843 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4845 constructor_type = TREE_TYPE (constructor_type);
4846 push_array_bounds (tree_low_cst (constructor_index, 0));
4847 constructor_depth++;
4850 if (constructor_type == 0)
4852 error_init ("extra brace group at end of initializer");
4853 constructor_fields = 0;
4854 constructor_unfilled_fields = 0;
4858 if (value && TREE_CODE (value) == CONSTRUCTOR)
4860 constructor_constant = TREE_CONSTANT (value);
4861 constructor_simple = TREE_STATIC (value);
4862 constructor_elements = CONSTRUCTOR_ELTS (value);
4863 if (constructor_elements
4864 && (TREE_CODE (constructor_type) == RECORD_TYPE
4865 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4866 set_nonincremental_init ();
4869 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4871 missing_braces_mentioned = 1;
4872 warning_init ("missing braces around initializer");
4875 if (TREE_CODE (constructor_type) == RECORD_TYPE
4876 || TREE_CODE (constructor_type) == UNION_TYPE)
4878 constructor_fields = TYPE_FIELDS (constructor_type);
4879 /* Skip any nameless bit fields at the beginning. */
4880 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4881 && DECL_NAME (constructor_fields) == 0)
4882 constructor_fields = TREE_CHAIN (constructor_fields);
4884 constructor_unfilled_fields = constructor_fields;
4885 constructor_bit_index = bitsize_zero_node;
4887 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4889 /* Vectors are like simple fixed-size arrays. */
4890 constructor_max_index =
4891 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4892 constructor_index = convert (bitsizetype, integer_zero_node);
4893 constructor_unfilled_index = constructor_index;
4895 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4897 if (TYPE_DOMAIN (constructor_type))
4899 constructor_max_index
4900 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4902 /* Detect non-empty initializations of zero-length arrays. */
4903 if (constructor_max_index == NULL_TREE
4904 && TYPE_SIZE (constructor_type))
4905 constructor_max_index = build_int_cst (NULL_TREE, -1);
4907 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4908 to initialize VLAs will cause a proper error; avoid tree
4909 checking errors as well by setting a safe value. */
4910 if (constructor_max_index
4911 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4912 constructor_max_index = build_int_cst (NULL_TREE, -1);
4915 = convert (bitsizetype,
4916 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4919 constructor_index = bitsize_zero_node;
4921 constructor_unfilled_index = constructor_index;
4922 if (value && TREE_CODE (value) == STRING_CST)
4924 /* We need to split the char/wchar array into individual
4925 characters, so that we don't have to special case it
4927 set_nonincremental_init_from_string (value);
4932 if (constructor_type != error_mark_node)
4933 warning_init ("braces around scalar initializer");
4934 constructor_fields = constructor_type;
4935 constructor_unfilled_fields = constructor_type;
4939 /* At the end of an implicit or explicit brace level,
4940 finish up that level of constructor. If a single expression
4941 with redundant braces initialized that level, return the
4942 c_expr structure for that expression. Otherwise, the original_code
4943 element is set to ERROR_MARK.
4944 If we were outputting the elements as they are read, return 0 as the value
4945 from inner levels (process_init_element ignores that),
4946 but return error_mark_node as the value from the outermost level
4947 (that's what we want to put in DECL_INITIAL).
4948 Otherwise, return a CONSTRUCTOR expression as the value. */
4951 pop_init_level (int implicit)
4953 struct constructor_stack *p;
4956 ret.original_code = ERROR_MARK;
4960 /* When we come to an explicit close brace,
4961 pop any inner levels that didn't have explicit braces. */
4962 while (constructor_stack->implicit)
4963 process_init_element (pop_init_level (1));
4965 gcc_assert (!constructor_range_stack);
4968 /* Now output all pending elements. */
4969 constructor_incremental = 1;
4970 output_pending_init_elements (1);
4972 p = constructor_stack;
4974 /* Error for initializing a flexible array member, or a zero-length
4975 array member in an inappropriate context. */
4976 if (constructor_type && constructor_fields
4977 && TREE_CODE (constructor_type) == ARRAY_TYPE
4978 && TYPE_DOMAIN (constructor_type)
4979 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
4981 /* Silently discard empty initializations. The parser will
4982 already have pedwarned for empty brackets. */
4983 if (integer_zerop (constructor_unfilled_index))
4984 constructor_type = NULL_TREE;
4987 gcc_assert (!TYPE_SIZE (constructor_type));
4989 if (constructor_depth > 2)
4990 error_init ("initialization of flexible array member in a nested context");
4992 pedwarn_init ("initialization of a flexible array member");
4994 /* We have already issued an error message for the existence
4995 of a flexible array member not at the end of the structure.
4996 Discard the initializer so that we do not abort later. */
4997 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
4998 constructor_type = NULL_TREE;
5002 /* Warn when some struct elements are implicitly initialized to zero. */
5003 if (warn_missing_field_initializers
5005 && TREE_CODE (constructor_type) == RECORD_TYPE
5006 && constructor_unfilled_fields)
5008 /* Do not warn for flexible array members or zero-length arrays. */
5009 while (constructor_unfilled_fields
5010 && (!DECL_SIZE (constructor_unfilled_fields)
5011 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5012 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5014 /* Do not warn if this level of the initializer uses member
5015 designators; it is likely to be deliberate. */
5016 if (constructor_unfilled_fields && !constructor_designated)
5018 push_member_name (constructor_unfilled_fields);
5019 warning_init ("missing initializer");
5020 RESTORE_SPELLING_DEPTH (constructor_depth);
5024 /* Pad out the end of the structure. */
5025 if (p->replacement_value.value)
5026 /* If this closes a superfluous brace pair,
5027 just pass out the element between them. */
5028 ret = p->replacement_value;
5029 else if (constructor_type == 0)
5031 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5032 && TREE_CODE (constructor_type) != UNION_TYPE
5033 && TREE_CODE (constructor_type) != ARRAY_TYPE
5034 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5036 /* A nonincremental scalar initializer--just return
5037 the element, after verifying there is just one. */
5038 if (constructor_elements == 0)
5040 if (!constructor_erroneous)
5041 error_init ("empty scalar initializer");
5042 ret.value = error_mark_node;
5044 else if (TREE_CHAIN (constructor_elements) != 0)
5046 error_init ("extra elements in scalar initializer");
5047 ret.value = TREE_VALUE (constructor_elements);
5050 ret.value = TREE_VALUE (constructor_elements);
5054 if (constructor_erroneous)
5055 ret.value = error_mark_node;
5058 ret.value = build_constructor (constructor_type,
5059 nreverse (constructor_elements));
5060 if (constructor_constant)
5061 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5062 if (constructor_constant && constructor_simple)
5063 TREE_STATIC (ret.value) = 1;
5067 constructor_type = p->type;
5068 constructor_fields = p->fields;
5069 constructor_index = p->index;
5070 constructor_max_index = p->max_index;
5071 constructor_unfilled_index = p->unfilled_index;
5072 constructor_unfilled_fields = p->unfilled_fields;
5073 constructor_bit_index = p->bit_index;
5074 constructor_elements = p->elements;
5075 constructor_constant = p->constant;
5076 constructor_simple = p->simple;
5077 constructor_erroneous = p->erroneous;
5078 constructor_incremental = p->incremental;
5079 constructor_designated = p->designated;
5080 constructor_pending_elts = p->pending_elts;
5081 constructor_depth = p->depth;
5083 constructor_range_stack = p->range_stack;
5084 RESTORE_SPELLING_DEPTH (constructor_depth);
5086 constructor_stack = p->next;
5091 if (constructor_stack == 0)
5093 ret.value = error_mark_node;
5101 /* Common handling for both array range and field name designators.
5102 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5105 set_designator (int array)
5108 enum tree_code subcode;
5110 /* Don't die if an entire brace-pair level is superfluous
5111 in the containing level. */
5112 if (constructor_type == 0)
5115 /* If there were errors in this designator list already, bail out
5117 if (designator_errorneous)
5120 if (!designator_depth)
5122 gcc_assert (!constructor_range_stack);
5124 /* Designator list starts at the level of closest explicit
5126 while (constructor_stack->implicit)
5127 process_init_element (pop_init_level (1));
5128 constructor_designated = 1;
5132 switch (TREE_CODE (constructor_type))
5136 subtype = TREE_TYPE (constructor_fields);
5137 if (subtype != error_mark_node)
5138 subtype = TYPE_MAIN_VARIANT (subtype);
5141 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5147 subcode = TREE_CODE (subtype);
5148 if (array && subcode != ARRAY_TYPE)
5150 error_init ("array index in non-array initializer");
5153 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5155 error_init ("field name not in record or union initializer");
5159 constructor_designated = 1;
5160 push_init_level (2);
5164 /* If there are range designators in designator list, push a new designator
5165 to constructor_range_stack. RANGE_END is end of such stack range or
5166 NULL_TREE if there is no range designator at this level. */
5169 push_range_stack (tree range_end)
5171 struct constructor_range_stack *p;
5173 p = GGC_NEW (struct constructor_range_stack);
5174 p->prev = constructor_range_stack;
5176 p->fields = constructor_fields;
5177 p->range_start = constructor_index;
5178 p->index = constructor_index;
5179 p->stack = constructor_stack;
5180 p->range_end = range_end;
5181 if (constructor_range_stack)
5182 constructor_range_stack->next = p;
5183 constructor_range_stack = p;
5186 /* Within an array initializer, specify the next index to be initialized.
5187 FIRST is that index. If LAST is nonzero, then initialize a range
5188 of indices, running from FIRST through LAST. */
5191 set_init_index (tree first, tree last)
5193 if (set_designator (1))
5196 designator_errorneous = 1;
5198 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5199 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5201 error_init ("array index in initializer not of integer type");
5205 while ((TREE_CODE (first) == NOP_EXPR
5206 || TREE_CODE (first) == CONVERT_EXPR
5207 || TREE_CODE (first) == NON_LVALUE_EXPR)
5208 && (TYPE_MODE (TREE_TYPE (first))
5209 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
5210 first = TREE_OPERAND (first, 0);
5213 while ((TREE_CODE (last) == NOP_EXPR
5214 || TREE_CODE (last) == CONVERT_EXPR
5215 || TREE_CODE (last) == NON_LVALUE_EXPR)
5216 && (TYPE_MODE (TREE_TYPE (last))
5217 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5218 last = TREE_OPERAND (last, 0);
5220 if (TREE_CODE (first) != INTEGER_CST)
5221 error_init ("nonconstant array index in initializer");
5222 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5223 error_init ("nonconstant array index in initializer");
5224 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5225 error_init ("array index in non-array initializer");
5226 else if (tree_int_cst_sgn (first) == -1)
5227 error_init ("array index in initializer exceeds array bounds");
5228 else if (constructor_max_index
5229 && tree_int_cst_lt (constructor_max_index, first))
5230 error_init ("array index in initializer exceeds array bounds");
5233 constructor_index = convert (bitsizetype, first);
5237 if (tree_int_cst_equal (first, last))
5239 else if (tree_int_cst_lt (last, first))
5241 error_init ("empty index range in initializer");
5246 last = convert (bitsizetype, last);
5247 if (constructor_max_index != 0
5248 && tree_int_cst_lt (constructor_max_index, last))
5250 error_init ("array index range in initializer exceeds array bounds");
5257 designator_errorneous = 0;
5258 if (constructor_range_stack || last)
5259 push_range_stack (last);
5263 /* Within a struct initializer, specify the next field to be initialized. */
5266 set_init_label (tree fieldname)
5270 if (set_designator (0))
5273 designator_errorneous = 1;
5275 if (TREE_CODE (constructor_type) != RECORD_TYPE
5276 && TREE_CODE (constructor_type) != UNION_TYPE)
5278 error_init ("field name not in record or union initializer");
5282 for (tail = TYPE_FIELDS (constructor_type); tail;
5283 tail = TREE_CHAIN (tail))
5285 if (DECL_NAME (tail) == fieldname)
5290 error ("unknown field %qs specified in initializer",
5291 IDENTIFIER_POINTER (fieldname));
5294 constructor_fields = tail;
5296 designator_errorneous = 0;
5297 if (constructor_range_stack)
5298 push_range_stack (NULL_TREE);
5302 /* Add a new initializer to the tree of pending initializers. PURPOSE
5303 identifies the initializer, either array index or field in a structure.
5304 VALUE is the value of that index or field. */
5307 add_pending_init (tree purpose, tree value)
5309 struct init_node *p, **q, *r;
5311 q = &constructor_pending_elts;
5314 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5319 if (tree_int_cst_lt (purpose, p->purpose))
5321 else if (tree_int_cst_lt (p->purpose, purpose))
5325 if (TREE_SIDE_EFFECTS (p->value))
5326 warning_init ("initialized field with side-effects overwritten");
5336 bitpos = bit_position (purpose);
5340 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5342 else if (p->purpose != purpose)
5346 if (TREE_SIDE_EFFECTS (p->value))
5347 warning_init ("initialized field with side-effects overwritten");
5354 r = GGC_NEW (struct init_node);
5355 r->purpose = purpose;
5366 struct init_node *s;
5370 if (p->balance == 0)
5372 else if (p->balance < 0)
5379 p->left->parent = p;
5396 constructor_pending_elts = r;
5401 struct init_node *t = r->right;
5405 r->right->parent = r;
5410 p->left->parent = p;
5413 p->balance = t->balance < 0;
5414 r->balance = -(t->balance > 0);
5429 constructor_pending_elts = t;
5435 /* p->balance == +1; growth of left side balances the node. */
5440 else /* r == p->right */
5442 if (p->balance == 0)
5443 /* Growth propagation from right side. */
5445 else if (p->balance > 0)
5452 p->right->parent = p;
5469 constructor_pending_elts = r;
5471 else /* r->balance == -1 */
5474 struct init_node *t = r->left;
5478 r->left->parent = r;
5483 p->right->parent = p;
5486 r->balance = (t->balance < 0);
5487 p->balance = -(t->balance > 0);
5502 constructor_pending_elts = t;
5508 /* p->balance == -1; growth of right side balances the node. */
5519 /* Build AVL tree from a sorted chain. */
5522 set_nonincremental_init (void)
5526 if (TREE_CODE (constructor_type) != RECORD_TYPE
5527 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5530 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5531 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5532 constructor_elements = 0;
5533 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5535 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5536 /* Skip any nameless bit fields at the beginning. */
5537 while (constructor_unfilled_fields != 0
5538 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5539 && DECL_NAME (constructor_unfilled_fields) == 0)
5540 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5543 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5545 if (TYPE_DOMAIN (constructor_type))
5546 constructor_unfilled_index
5547 = convert (bitsizetype,
5548 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5550 constructor_unfilled_index = bitsize_zero_node;
5552 constructor_incremental = 0;
5555 /* Build AVL tree from a string constant. */
5558 set_nonincremental_init_from_string (tree str)
5560 tree value, purpose, type;
5561 HOST_WIDE_INT val[2];
5562 const char *p, *end;
5563 int byte, wchar_bytes, charwidth, bitpos;
5565 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5567 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5568 == TYPE_PRECISION (char_type_node))
5572 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5573 == TYPE_PRECISION (wchar_type_node));
5574 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5576 charwidth = TYPE_PRECISION (char_type_node);
5577 type = TREE_TYPE (constructor_type);
5578 p = TREE_STRING_POINTER (str);
5579 end = p + TREE_STRING_LENGTH (str);
5581 for (purpose = bitsize_zero_node;
5582 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5583 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5585 if (wchar_bytes == 1)
5587 val[1] = (unsigned char) *p++;
5594 for (byte = 0; byte < wchar_bytes; byte++)
5596 if (BYTES_BIG_ENDIAN)
5597 bitpos = (wchar_bytes - byte - 1) * charwidth;
5599 bitpos = byte * charwidth;
5600 val[bitpos < HOST_BITS_PER_WIDE_INT]
5601 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5602 << (bitpos % HOST_BITS_PER_WIDE_INT);
5606 if (!TYPE_UNSIGNED (type))
5608 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5609 if (bitpos < HOST_BITS_PER_WIDE_INT)
5611 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5613 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5617 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5622 else if (val[0] & (((HOST_WIDE_INT) 1)
5623 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5624 val[0] |= ((HOST_WIDE_INT) -1)
5625 << (bitpos - HOST_BITS_PER_WIDE_INT);
5628 value = build_int_cst_wide (type, val[1], val[0]);
5629 add_pending_init (purpose, value);
5632 constructor_incremental = 0;
5635 /* Return value of FIELD in pending initializer or zero if the field was
5636 not initialized yet. */
5639 find_init_member (tree field)
5641 struct init_node *p;
5643 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5645 if (constructor_incremental
5646 && tree_int_cst_lt (field, constructor_unfilled_index))
5647 set_nonincremental_init ();
5649 p = constructor_pending_elts;
5652 if (tree_int_cst_lt (field, p->purpose))
5654 else if (tree_int_cst_lt (p->purpose, field))
5660 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5662 tree bitpos = bit_position (field);
5664 if (constructor_incremental
5665 && (!constructor_unfilled_fields
5666 || tree_int_cst_lt (bitpos,
5667 bit_position (constructor_unfilled_fields))))
5668 set_nonincremental_init ();
5670 p = constructor_pending_elts;
5673 if (field == p->purpose)
5675 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5681 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5683 if (constructor_elements
5684 && TREE_PURPOSE (constructor_elements) == field)
5685 return TREE_VALUE (constructor_elements);
5690 /* "Output" the next constructor element.
5691 At top level, really output it to assembler code now.
5692 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5693 TYPE is the data type that the containing data type wants here.
5694 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5695 If VALUE is a string constant, STRICT_STRING is true if it is
5696 unparenthesized or we should not warn here for it being parenthesized.
5697 For other types of VALUE, STRICT_STRING is not used.
5699 PENDING if non-nil means output pending elements that belong
5700 right after this element. (PENDING is normally 1;
5701 it is 0 while outputting pending elements, to avoid recursion.) */
5704 output_init_element (tree value, bool strict_string, tree type, tree field,
5707 if (type == error_mark_node || value == error_mark_node)
5709 constructor_erroneous = 1;
5712 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5713 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5714 && !(TREE_CODE (value) == STRING_CST
5715 && TREE_CODE (type) == ARRAY_TYPE
5716 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5717 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5718 TYPE_MAIN_VARIANT (type))))
5719 value = default_conversion (value);
5721 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5722 && require_constant_value && !flag_isoc99 && pending)
5724 /* As an extension, allow initializing objects with static storage
5725 duration with compound literals (which are then treated just as
5726 the brace enclosed list they contain). */
5727 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5728 value = DECL_INITIAL (decl);
5731 if (value == error_mark_node)
5732 constructor_erroneous = 1;
5733 else if (!TREE_CONSTANT (value))
5734 constructor_constant = 0;
5735 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5736 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5737 || TREE_CODE (constructor_type) == UNION_TYPE)
5738 && DECL_C_BIT_FIELD (field)
5739 && TREE_CODE (value) != INTEGER_CST))
5740 constructor_simple = 0;
5742 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5744 if (require_constant_value)
5746 error_init ("initializer element is not constant");
5747 value = error_mark_node;
5749 else if (require_constant_elements)
5750 pedwarn ("initializer element is not computable at load time");
5753 /* If this field is empty (and not at the end of structure),
5754 don't do anything other than checking the initializer. */
5756 && (TREE_TYPE (field) == error_mark_node
5757 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5758 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5759 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5760 || TREE_CHAIN (field)))))
5763 value = digest_init (type, value, strict_string, require_constant_value);
5764 if (value == error_mark_node)
5766 constructor_erroneous = 1;
5770 /* If this element doesn't come next in sequence,
5771 put it on constructor_pending_elts. */
5772 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5773 && (!constructor_incremental
5774 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5776 if (constructor_incremental
5777 && tree_int_cst_lt (field, constructor_unfilled_index))
5778 set_nonincremental_init ();
5780 add_pending_init (field, value);
5783 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5784 && (!constructor_incremental
5785 || field != constructor_unfilled_fields))
5787 /* We do this for records but not for unions. In a union,
5788 no matter which field is specified, it can be initialized
5789 right away since it starts at the beginning of the union. */
5790 if (constructor_incremental)
5792 if (!constructor_unfilled_fields)
5793 set_nonincremental_init ();
5796 tree bitpos, unfillpos;
5798 bitpos = bit_position (field);
5799 unfillpos = bit_position (constructor_unfilled_fields);
5801 if (tree_int_cst_lt (bitpos, unfillpos))
5802 set_nonincremental_init ();
5806 add_pending_init (field, value);
5809 else if (TREE_CODE (constructor_type) == UNION_TYPE
5810 && constructor_elements)
5812 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5813 warning_init ("initialized field with side-effects overwritten");
5815 /* We can have just one union field set. */
5816 constructor_elements = 0;
5819 /* Otherwise, output this element either to
5820 constructor_elements or to the assembler file. */
5822 if (field && TREE_CODE (field) == INTEGER_CST)
5823 field = copy_node (field);
5824 constructor_elements
5825 = tree_cons (field, value, constructor_elements);
5827 /* Advance the variable that indicates sequential elements output. */
5828 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5829 constructor_unfilled_index
5830 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5832 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5834 constructor_unfilled_fields
5835 = TREE_CHAIN (constructor_unfilled_fields);
5837 /* Skip any nameless bit fields. */
5838 while (constructor_unfilled_fields != 0
5839 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5840 && DECL_NAME (constructor_unfilled_fields) == 0)
5841 constructor_unfilled_fields =
5842 TREE_CHAIN (constructor_unfilled_fields);
5844 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5845 constructor_unfilled_fields = 0;
5847 /* Now output any pending elements which have become next. */
5849 output_pending_init_elements (0);
5852 /* Output any pending elements which have become next.
5853 As we output elements, constructor_unfilled_{fields,index}
5854 advances, which may cause other elements to become next;
5855 if so, they too are output.
5857 If ALL is 0, we return when there are
5858 no more pending elements to output now.
5860 If ALL is 1, we output space as necessary so that
5861 we can output all the pending elements. */
5864 output_pending_init_elements (int all)
5866 struct init_node *elt = constructor_pending_elts;
5871 /* Look through the whole pending tree.
5872 If we find an element that should be output now,
5873 output it. Otherwise, set NEXT to the element
5874 that comes first among those still pending. */
5879 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5881 if (tree_int_cst_equal (elt->purpose,
5882 constructor_unfilled_index))
5883 output_init_element (elt->value, true,
5884 TREE_TYPE (constructor_type),
5885 constructor_unfilled_index, 0);
5886 else if (tree_int_cst_lt (constructor_unfilled_index,
5889 /* Advance to the next smaller node. */
5894 /* We have reached the smallest node bigger than the
5895 current unfilled index. Fill the space first. */
5896 next = elt->purpose;
5902 /* Advance to the next bigger node. */
5907 /* We have reached the biggest node in a subtree. Find
5908 the parent of it, which is the next bigger node. */
5909 while (elt->parent && elt->parent->right == elt)
5912 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5915 next = elt->purpose;
5921 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5922 || TREE_CODE (constructor_type) == UNION_TYPE)
5924 tree ctor_unfilled_bitpos, elt_bitpos;
5926 /* If the current record is complete we are done. */
5927 if (constructor_unfilled_fields == 0)
5930 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
5931 elt_bitpos = bit_position (elt->purpose);
5932 /* We can't compare fields here because there might be empty
5933 fields in between. */
5934 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
5936 constructor_unfilled_fields = elt->purpose;
5937 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
5940 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
5942 /* Advance to the next smaller node. */
5947 /* We have reached the smallest node bigger than the
5948 current unfilled field. Fill the space first. */
5949 next = elt->purpose;
5955 /* Advance to the next bigger node. */
5960 /* We have reached the biggest node in a subtree. Find
5961 the parent of it, which is the next bigger node. */
5962 while (elt->parent && elt->parent->right == elt)
5966 && (tree_int_cst_lt (ctor_unfilled_bitpos,
5967 bit_position (elt->purpose))))
5969 next = elt->purpose;
5977 /* Ordinarily return, but not if we want to output all
5978 and there are elements left. */
5979 if (!(all && next != 0))
5982 /* If it's not incremental, just skip over the gap, so that after
5983 jumping to retry we will output the next successive element. */
5984 if (TREE_CODE (constructor_type) == RECORD_TYPE
5985 || TREE_CODE (constructor_type) == UNION_TYPE)
5986 constructor_unfilled_fields = next;
5987 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5988 constructor_unfilled_index = next;
5990 /* ELT now points to the node in the pending tree with the next
5991 initializer to output. */
5995 /* Add one non-braced element to the current constructor level.
5996 This adjusts the current position within the constructor's type.
5997 This may also start or terminate implicit levels
5998 to handle a partly-braced initializer.
6000 Once this has found the correct level for the new element,
6001 it calls output_init_element. */
6004 process_init_element (struct c_expr value)
6006 tree orig_value = value.value;
6007 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6008 bool strict_string = value.original_code == STRING_CST;
6010 designator_depth = 0;
6011 designator_errorneous = 0;
6013 /* Handle superfluous braces around string cst as in
6014 char x[] = {"foo"}; */
6017 && TREE_CODE (constructor_type) == ARRAY_TYPE
6018 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6019 && integer_zerop (constructor_unfilled_index))
6021 if (constructor_stack->replacement_value.value)
6022 error_init ("excess elements in char array initializer");
6023 constructor_stack->replacement_value = value;
6027 if (constructor_stack->replacement_value.value != 0)
6029 error_init ("excess elements in struct initializer");
6033 /* Ignore elements of a brace group if it is entirely superfluous
6034 and has already been diagnosed. */
6035 if (constructor_type == 0)
6038 /* If we've exhausted any levels that didn't have braces,
6040 while (constructor_stack->implicit)
6042 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6043 || TREE_CODE (constructor_type) == UNION_TYPE)
6044 && constructor_fields == 0)
6045 process_init_element (pop_init_level (1));
6046 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6047 && (constructor_max_index == 0
6048 || tree_int_cst_lt (constructor_max_index,
6049 constructor_index)))
6050 process_init_element (pop_init_level (1));
6055 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6056 if (constructor_range_stack)
6058 /* If value is a compound literal and we'll be just using its
6059 content, don't put it into a SAVE_EXPR. */
6060 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6061 || !require_constant_value
6063 value.value = save_expr (value.value);
6068 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6071 enum tree_code fieldcode;
6073 if (constructor_fields == 0)
6075 pedwarn_init ("excess elements in struct initializer");
6079 fieldtype = TREE_TYPE (constructor_fields);
6080 if (fieldtype != error_mark_node)
6081 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6082 fieldcode = TREE_CODE (fieldtype);
6084 /* Error for non-static initialization of a flexible array member. */
6085 if (fieldcode == ARRAY_TYPE
6086 && !require_constant_value
6087 && TYPE_SIZE (fieldtype) == NULL_TREE
6088 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6090 error_init ("non-static initialization of a flexible array member");
6094 /* Accept a string constant to initialize a subarray. */
6095 if (value.value != 0
6096 && fieldcode == ARRAY_TYPE
6097 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6099 value.value = orig_value;
6100 /* Otherwise, if we have come to a subaggregate,
6101 and we don't have an element of its type, push into it. */
6102 else if (value.value != 0
6103 && value.value != error_mark_node
6104 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6105 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6106 || fieldcode == UNION_TYPE))
6108 push_init_level (1);
6114 push_member_name (constructor_fields);
6115 output_init_element (value.value, strict_string,
6116 fieldtype, constructor_fields, 1);
6117 RESTORE_SPELLING_DEPTH (constructor_depth);
6120 /* Do the bookkeeping for an element that was
6121 directly output as a constructor. */
6123 /* For a record, keep track of end position of last field. */
6124 if (DECL_SIZE (constructor_fields))
6125 constructor_bit_index
6126 = size_binop (PLUS_EXPR,
6127 bit_position (constructor_fields),
6128 DECL_SIZE (constructor_fields));
6130 /* If the current field was the first one not yet written out,
6131 it isn't now, so update. */
6132 if (constructor_unfilled_fields == constructor_fields)
6134 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6135 /* Skip any nameless bit fields. */
6136 while (constructor_unfilled_fields != 0
6137 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6138 && DECL_NAME (constructor_unfilled_fields) == 0)
6139 constructor_unfilled_fields =
6140 TREE_CHAIN (constructor_unfilled_fields);
6144 constructor_fields = TREE_CHAIN (constructor_fields);
6145 /* Skip any nameless bit fields at the beginning. */
6146 while (constructor_fields != 0
6147 && DECL_C_BIT_FIELD (constructor_fields)
6148 && DECL_NAME (constructor_fields) == 0)
6149 constructor_fields = TREE_CHAIN (constructor_fields);
6151 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6154 enum tree_code fieldcode;
6156 if (constructor_fields == 0)
6158 pedwarn_init ("excess elements in union initializer");
6162 fieldtype = TREE_TYPE (constructor_fields);
6163 if (fieldtype != error_mark_node)
6164 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6165 fieldcode = TREE_CODE (fieldtype);
6167 /* Warn that traditional C rejects initialization of unions.
6168 We skip the warning if the value is zero. This is done
6169 under the assumption that the zero initializer in user
6170 code appears conditioned on e.g. __STDC__ to avoid
6171 "missing initializer" warnings and relies on default
6172 initialization to zero in the traditional C case.
6173 We also skip the warning if the initializer is designated,
6174 again on the assumption that this must be conditional on
6175 __STDC__ anyway (and we've already complained about the
6176 member-designator already). */
6177 if (warn_traditional && !in_system_header && !constructor_designated
6178 && !(value.value && (integer_zerop (value.value)
6179 || real_zerop (value.value))))
6180 warning ("traditional C rejects initialization of unions");
6182 /* Accept a string constant to initialize a subarray. */
6183 if (value.value != 0
6184 && fieldcode == ARRAY_TYPE
6185 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6187 value.value = orig_value;
6188 /* Otherwise, if we have come to a subaggregate,
6189 and we don't have an element of its type, push into it. */
6190 else if (value.value != 0
6191 && value.value != error_mark_node
6192 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6193 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6194 || fieldcode == UNION_TYPE))
6196 push_init_level (1);
6202 push_member_name (constructor_fields);
6203 output_init_element (value.value, strict_string,
6204 fieldtype, constructor_fields, 1);
6205 RESTORE_SPELLING_DEPTH (constructor_depth);
6208 /* Do the bookkeeping for an element that was
6209 directly output as a constructor. */
6211 constructor_bit_index = DECL_SIZE (constructor_fields);
6212 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6215 constructor_fields = 0;
6217 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6219 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6220 enum tree_code eltcode = TREE_CODE (elttype);
6222 /* Accept a string constant to initialize a subarray. */
6223 if (value.value != 0
6224 && eltcode == ARRAY_TYPE
6225 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6227 value.value = orig_value;
6228 /* Otherwise, if we have come to a subaggregate,
6229 and we don't have an element of its type, push into it. */
6230 else if (value.value != 0
6231 && value.value != error_mark_node
6232 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6233 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6234 || eltcode == UNION_TYPE))
6236 push_init_level (1);
6240 if (constructor_max_index != 0
6241 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6242 || integer_all_onesp (constructor_max_index)))
6244 pedwarn_init ("excess elements in array initializer");
6248 /* Now output the actual element. */
6251 push_array_bounds (tree_low_cst (constructor_index, 0));
6252 output_init_element (value.value, strict_string,
6253 elttype, constructor_index, 1);
6254 RESTORE_SPELLING_DEPTH (constructor_depth);
6258 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6261 /* If we are doing the bookkeeping for an element that was
6262 directly output as a constructor, we must update
6263 constructor_unfilled_index. */
6264 constructor_unfilled_index = constructor_index;
6266 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6268 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6270 /* Do a basic check of initializer size. Note that vectors
6271 always have a fixed size derived from their type. */
6272 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6274 pedwarn_init ("excess elements in vector initializer");
6278 /* Now output the actual element. */
6280 output_init_element (value.value, strict_string,
6281 elttype, constructor_index, 1);
6284 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6287 /* If we are doing the bookkeeping for an element that was
6288 directly output as a constructor, we must update
6289 constructor_unfilled_index. */
6290 constructor_unfilled_index = constructor_index;
6293 /* Handle the sole element allowed in a braced initializer
6294 for a scalar variable. */
6295 else if (constructor_type != error_mark_node
6296 && constructor_fields == 0)
6298 pedwarn_init ("excess elements in scalar initializer");
6304 output_init_element (value.value, strict_string,
6305 constructor_type, NULL_TREE, 1);
6306 constructor_fields = 0;
6309 /* Handle range initializers either at this level or anywhere higher
6310 in the designator stack. */
6311 if (constructor_range_stack)
6313 struct constructor_range_stack *p, *range_stack;
6316 range_stack = constructor_range_stack;
6317 constructor_range_stack = 0;
6318 while (constructor_stack != range_stack->stack)
6320 gcc_assert (constructor_stack->implicit);
6321 process_init_element (pop_init_level (1));
6323 for (p = range_stack;
6324 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6327 gcc_assert (constructor_stack->implicit);
6328 process_init_element (pop_init_level (1));
6331 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6332 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6337 constructor_index = p->index;
6338 constructor_fields = p->fields;
6339 if (finish && p->range_end && p->index == p->range_start)
6347 push_init_level (2);
6348 p->stack = constructor_stack;
6349 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6350 p->index = p->range_start;
6354 constructor_range_stack = range_stack;
6361 constructor_range_stack = 0;
6364 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6365 (guaranteed to be 'volatile' or null) and ARGS (represented using
6366 an ASM_EXPR node). */
6368 build_asm_stmt (tree cv_qualifier, tree args)
6370 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6371 ASM_VOLATILE_P (args) = 1;
6372 return add_stmt (args);
6375 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6376 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6377 SIMPLE indicates whether there was anything at all after the
6378 string in the asm expression -- asm("blah") and asm("blah" : )
6379 are subtly different. We use a ASM_EXPR node to represent this. */
6381 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6387 const char *constraint;
6388 const char **oconstraints;
6389 bool allows_mem, allows_reg, is_inout;
6390 int ninputs, noutputs;
6392 ninputs = list_length (inputs);
6393 noutputs = list_length (outputs);
6394 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6396 string = resolve_asm_operand_names (string, outputs, inputs);
6398 /* Remove output conversions that change the type but not the mode. */
6399 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6401 tree output = TREE_VALUE (tail);
6403 /* ??? Really, this should not be here. Users should be using a
6404 proper lvalue, dammit. But there's a long history of using casts
6405 in the output operands. In cases like longlong.h, this becomes a
6406 primitive form of typechecking -- if the cast can be removed, then
6407 the output operand had a type of the proper width; otherwise we'll
6408 get an error. Gross, but ... */
6409 STRIP_NOPS (output);
6411 if (!lvalue_or_else (output, lv_asm))
6412 output = error_mark_node;
6414 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6415 oconstraints[i] = constraint;
6417 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6418 &allows_mem, &allows_reg, &is_inout))
6420 /* If the operand is going to end up in memory,
6421 mark it addressable. */
6422 if (!allows_reg && !c_mark_addressable (output))
6423 output = error_mark_node;
6426 output = error_mark_node;
6428 TREE_VALUE (tail) = output;
6431 /* Perform default conversions on array and function inputs.
6432 Don't do this for other types as it would screw up operands
6433 expected to be in memory. */
6434 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6438 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6439 input = TREE_VALUE (tail);
6441 input = default_function_array_conversion (input);
6443 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6444 oconstraints, &allows_mem, &allows_reg))
6446 /* If the operand is going to end up in memory,
6447 mark it addressable. */
6448 if (!allows_reg && allows_mem)
6450 /* Strip the nops as we allow this case. FIXME, this really
6451 should be rejected or made deprecated. */
6453 if (!c_mark_addressable (input))
6454 input = error_mark_node;
6458 input = error_mark_node;
6460 TREE_VALUE (tail) = input;
6463 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6465 /* Simple asm statements are treated as volatile. */
6468 ASM_VOLATILE_P (args) = 1;
6469 ASM_INPUT_P (args) = 1;
6475 /* Generate a goto statement to LABEL. */
6478 c_finish_goto_label (tree label)
6480 tree decl = lookup_label (label);
6484 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6486 error ("jump into statement expression");
6490 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6492 /* No jump from outside this statement expression context, so
6493 record that there is a jump from within this context. */
6494 struct c_label_list *nlist;
6495 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6496 nlist->next = label_context_stack->labels_used;
6497 nlist->label = decl;
6498 label_context_stack->labels_used = nlist;
6501 TREE_USED (decl) = 1;
6502 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6505 /* Generate a computed goto statement to EXPR. */
6508 c_finish_goto_ptr (tree expr)
6511 pedwarn ("ISO C forbids %<goto *expr;%>");
6512 expr = convert (ptr_type_node, expr);
6513 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6516 /* Generate a C `return' statement. RETVAL is the expression for what
6517 to return, or a null pointer for `return;' with no value. */
6520 c_finish_return (tree retval)
6522 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6524 if (TREE_THIS_VOLATILE (current_function_decl))
6525 warning ("function declared %<noreturn%> has a %<return%> statement");
6529 current_function_returns_null = 1;
6530 if ((warn_return_type || flag_isoc99)
6531 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6532 pedwarn_c99 ("%<return%> with no value, in "
6533 "function returning non-void");
6535 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6537 current_function_returns_null = 1;
6538 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6539 pedwarn ("%<return%> with a value, in function returning void");
6543 tree t = convert_for_assignment (valtype, retval, ic_return,
6544 NULL_TREE, NULL_TREE, 0);
6545 tree res = DECL_RESULT (current_function_decl);
6548 current_function_returns_value = 1;
6549 if (t == error_mark_node)
6552 inner = t = convert (TREE_TYPE (res), t);
6554 /* Strip any conversions, additions, and subtractions, and see if
6555 we are returning the address of a local variable. Warn if so. */
6558 switch (TREE_CODE (inner))
6560 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6562 inner = TREE_OPERAND (inner, 0);
6566 /* If the second operand of the MINUS_EXPR has a pointer
6567 type (or is converted from it), this may be valid, so
6568 don't give a warning. */
6570 tree op1 = TREE_OPERAND (inner, 1);
6572 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6573 && (TREE_CODE (op1) == NOP_EXPR
6574 || TREE_CODE (op1) == NON_LVALUE_EXPR
6575 || TREE_CODE (op1) == CONVERT_EXPR))
6576 op1 = TREE_OPERAND (op1, 0);
6578 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6581 inner = TREE_OPERAND (inner, 0);
6586 inner = TREE_OPERAND (inner, 0);
6588 while (REFERENCE_CLASS_P (inner)
6589 && TREE_CODE (inner) != INDIRECT_REF)
6590 inner = TREE_OPERAND (inner, 0);
6593 && !DECL_EXTERNAL (inner)
6594 && !TREE_STATIC (inner)
6595 && DECL_CONTEXT (inner) == current_function_decl)
6596 warning ("function returns address of local variable");
6606 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6609 return add_stmt (build_stmt (RETURN_EXPR, retval));
6613 /* The SWITCH_STMT being built. */
6616 /* The original type of the testing expression, i.e. before the
6617 default conversion is applied. */
6620 /* A splay-tree mapping the low element of a case range to the high
6621 element, or NULL_TREE if there is no high element. Used to
6622 determine whether or not a new case label duplicates an old case
6623 label. We need a tree, rather than simply a hash table, because
6624 of the GNU case range extension. */
6627 /* Number of nested statement expressions within this switch
6628 statement; if nonzero, case and default labels may not
6630 unsigned int blocked_stmt_expr;
6632 /* The next node on the stack. */
6633 struct c_switch *next;
6636 /* A stack of the currently active switch statements. The innermost
6637 switch statement is on the top of the stack. There is no need to
6638 mark the stack for garbage collection because it is only active
6639 during the processing of the body of a function, and we never
6640 collect at that point. */
6642 struct c_switch *c_switch_stack;
6644 /* Start a C switch statement, testing expression EXP. Return the new
6648 c_start_case (tree exp)
6650 enum tree_code code;
6651 tree type, orig_type = error_mark_node;
6652 struct c_switch *cs;
6654 if (exp != error_mark_node)
6656 code = TREE_CODE (TREE_TYPE (exp));
6657 orig_type = TREE_TYPE (exp);
6659 if (!INTEGRAL_TYPE_P (orig_type)
6660 && code != ERROR_MARK)
6662 error ("switch quantity not an integer");
6663 exp = integer_zero_node;
6664 orig_type = error_mark_node;
6668 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6670 if (warn_traditional && !in_system_header
6671 && (type == long_integer_type_node
6672 || type == long_unsigned_type_node))
6673 warning ("%<long%> switch expression not converted to "
6674 "%<int%> in ISO C");
6676 exp = default_conversion (exp);
6677 type = TREE_TYPE (exp);
6681 /* Add this new SWITCH_STMT to the stack. */
6682 cs = XNEW (struct c_switch);
6683 cs->switch_stmt = build_stmt (SWITCH_STMT, exp, NULL_TREE, orig_type);
6684 cs->orig_type = orig_type;
6685 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6686 cs->blocked_stmt_expr = 0;
6687 cs->next = c_switch_stack;
6688 c_switch_stack = cs;
6690 return add_stmt (cs->switch_stmt);
6693 /* Process a case label. */
6696 do_case (tree low_value, tree high_value)
6698 tree label = NULL_TREE;
6700 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr)
6702 label = c_add_case_label (c_switch_stack->cases,
6703 SWITCH_STMT_COND (c_switch_stack->switch_stmt),
6704 c_switch_stack->orig_type,
6705 low_value, high_value);
6706 if (label == error_mark_node)
6709 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
6712 error ("case label in statement expression not containing "
6713 "enclosing switch statement");
6715 error ("%<default%> label in statement expression not containing "
6716 "enclosing switch statement");
6719 error ("case label not within a switch statement");
6721 error ("%<default%> label not within a switch statement");
6726 /* Finish the switch statement. */
6729 c_finish_case (tree body)
6731 struct c_switch *cs = c_switch_stack;
6733 SWITCH_STMT_BODY (cs->switch_stmt) = body;
6735 gcc_assert (!cs->blocked_stmt_expr);
6737 /* Emit warnings as needed. */
6738 c_do_switch_warnings (cs->cases, cs->switch_stmt);
6740 /* Pop the stack. */
6741 c_switch_stack = cs->next;
6742 splay_tree_delete (cs->cases);
6746 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6747 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6748 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6749 statement, and was not surrounded with parenthesis. */
6752 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6753 tree else_block, bool nested_if)
6757 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6758 if (warn_parentheses && nested_if && else_block == NULL)
6760 tree inner_if = then_block;
6762 /* We know from the grammar productions that there is an IF nested
6763 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6764 it might not be exactly THEN_BLOCK, but should be the last
6765 non-container statement within. */
6767 switch (TREE_CODE (inner_if))
6772 inner_if = BIND_EXPR_BODY (inner_if);
6774 case STATEMENT_LIST:
6775 inner_if = expr_last (then_block);
6777 case TRY_FINALLY_EXPR:
6778 case TRY_CATCH_EXPR:
6779 inner_if = TREE_OPERAND (inner_if, 0);
6786 if (COND_EXPR_ELSE (inner_if))
6787 warning ("%Hsuggest explicit braces to avoid ambiguous %<else%>",
6791 /* Diagnose ";" via the special empty statement node that we create. */
6794 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6797 warning ("%Hempty body in an if-statement",
6798 EXPR_LOCUS (then_block));
6799 then_block = alloc_stmt_list ();
6802 && TREE_CODE (else_block) == NOP_EXPR
6803 && !TREE_TYPE (else_block))
6805 warning ("%Hempty body in an else-statement",
6806 EXPR_LOCUS (else_block));
6807 else_block = alloc_stmt_list ();
6811 stmt = build3 (COND_EXPR, NULL_TREE, cond, then_block, else_block);
6812 SET_EXPR_LOCATION (stmt, if_locus);
6816 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6817 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6818 is false for DO loops. INCR is the FOR increment expression. BODY is
6819 the statement controlled by the loop. BLAB is the break label. CLAB is
6820 the continue label. Everything is allowed to be NULL. */
6823 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6824 tree blab, tree clab, bool cond_is_first)
6826 tree entry = NULL, exit = NULL, t;
6828 /* If the condition is zero don't generate a loop construct. */
6829 if (cond && integer_zerop (cond))
6833 t = build_and_jump (&blab);
6834 SET_EXPR_LOCATION (t, start_locus);
6840 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6842 /* If we have an exit condition, then we build an IF with gotos either
6843 out of the loop, or to the top of it. If there's no exit condition,
6844 then we just build a jump back to the top. */
6845 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6847 if (cond && !integer_nonzerop (cond))
6849 /* Canonicalize the loop condition to the end. This means
6850 generating a branch to the loop condition. Reuse the
6851 continue label, if possible. */
6856 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6857 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
6860 t = build1 (GOTO_EXPR, void_type_node, clab);
6861 SET_EXPR_LOCATION (t, start_locus);
6865 t = build_and_jump (&blab);
6866 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
6869 SET_EXPR_LOCATION (exit, start_locus);
6871 SET_EXPR_LOCATION (exit, input_location);
6880 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
6888 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
6892 c_finish_bc_stmt (tree *label_p, bool is_break)
6895 tree label = *label_p;
6897 /* In switch statements break is sometimes stylistically used after
6898 a return statement. This can lead to spurious warnings about
6899 control reaching the end of a non-void function when it is
6900 inlined. Note that we are calling block_may_fallthru with
6901 language specific tree nodes; this works because
6902 block_may_fallthru returns true when given something it does not
6904 skip = !block_may_fallthru (cur_stmt_list);
6909 *label_p = label = create_artificial_label ();
6911 else if (TREE_CODE (label) != LABEL_DECL)
6914 error ("break statement not within loop or switch");
6916 error ("continue statement not within a loop");
6923 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
6926 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
6929 emit_side_effect_warnings (tree expr)
6931 if (expr == error_mark_node)
6933 else if (!TREE_SIDE_EFFECTS (expr))
6935 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
6936 warning ("%Hstatement with no effect",
6937 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
6939 else if (warn_unused_value)
6940 warn_if_unused_value (expr, input_location);
6943 /* Process an expression as if it were a complete statement. Emit
6944 diagnostics, but do not call ADD_STMT. */
6947 c_process_expr_stmt (tree expr)
6952 /* Do default conversion if safe and possibly important,
6953 in case within ({...}). */
6954 if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
6955 && (flag_isoc99 || lvalue_p (expr)))
6956 || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
6957 expr = default_conversion (expr);
6959 if (warn_sequence_point)
6960 verify_sequence_points (expr);
6962 if (TREE_TYPE (expr) != error_mark_node
6963 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
6964 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
6965 error ("expression statement has incomplete type");
6967 /* If we're not processing a statement expression, warn about unused values.
6968 Warnings for statement expressions will be emitted later, once we figure
6969 out which is the result. */
6970 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
6971 && (extra_warnings || warn_unused_value))
6972 emit_side_effect_warnings (expr);
6974 /* If the expression is not of a type to which we cannot assign a line
6975 number, wrap the thing in a no-op NOP_EXPR. */
6976 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
6977 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
6980 SET_EXPR_LOCATION (expr, input_location);
6985 /* Emit an expression as a statement. */
6988 c_finish_expr_stmt (tree expr)
6991 return add_stmt (c_process_expr_stmt (expr));
6996 /* Do the opposite and emit a statement as an expression. To begin,
6997 create a new binding level and return it. */
7000 c_begin_stmt_expr (void)
7003 struct c_label_context *nstack;
7004 struct c_label_list *glist;
7006 /* We must force a BLOCK for this level so that, if it is not expanded
7007 later, there is a way to turn off the entire subtree of blocks that
7008 are contained in it. */
7010 ret = c_begin_compound_stmt (true);
7013 c_switch_stack->blocked_stmt_expr++;
7014 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7016 for (glist = label_context_stack->labels_used;
7018 glist = glist->next)
7020 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7022 nstack = XOBNEW (&parser_obstack, struct c_label_context);
7023 nstack->labels_def = NULL;
7024 nstack->labels_used = NULL;
7025 nstack->next = label_context_stack;
7026 label_context_stack = nstack;
7028 /* Mark the current statement list as belonging to a statement list. */
7029 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7035 c_finish_stmt_expr (tree body)
7037 tree last, type, tmp, val;
7039 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7041 body = c_end_compound_stmt (body, true);
7044 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7045 c_switch_stack->blocked_stmt_expr--;
7047 /* It is no longer possible to jump to labels defined within this
7048 statement expression. */
7049 for (dlist = label_context_stack->labels_def;
7051 dlist = dlist->next)
7053 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7055 /* It is again possible to define labels with a goto just outside
7056 this statement expression. */
7057 for (glist = label_context_stack->next->labels_used;
7059 glist = glist->next)
7061 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7064 if (glist_prev != NULL)
7065 glist_prev->next = label_context_stack->labels_used;
7067 label_context_stack->next->labels_used = label_context_stack->labels_used;
7068 label_context_stack = label_context_stack->next;
7070 /* Locate the last statement in BODY. See c_end_compound_stmt
7071 about always returning a BIND_EXPR. */
7072 last_p = &BIND_EXPR_BODY (body);
7073 last = BIND_EXPR_BODY (body);
7076 if (TREE_CODE (last) == STATEMENT_LIST)
7078 tree_stmt_iterator i;
7080 /* This can happen with degenerate cases like ({ }). No value. */
7081 if (!TREE_SIDE_EFFECTS (last))
7084 /* If we're supposed to generate side effects warnings, process
7085 all of the statements except the last. */
7086 if (extra_warnings || warn_unused_value)
7088 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7089 emit_side_effect_warnings (tsi_stmt (i));
7092 i = tsi_last (last);
7093 last_p = tsi_stmt_ptr (i);
7097 /* If the end of the list is exception related, then the list was split
7098 by a call to push_cleanup. Continue searching. */
7099 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7100 || TREE_CODE (last) == TRY_CATCH_EXPR)
7102 last_p = &TREE_OPERAND (last, 0);
7104 goto continue_searching;
7107 /* In the case that the BIND_EXPR is not necessary, return the
7108 expression out from inside it. */
7109 if (last == error_mark_node
7110 || (last == BIND_EXPR_BODY (body)
7111 && BIND_EXPR_VARS (body) == NULL))
7114 /* Extract the type of said expression. */
7115 type = TREE_TYPE (last);
7117 /* If we're not returning a value at all, then the BIND_EXPR that
7118 we already have is a fine expression to return. */
7119 if (!type || VOID_TYPE_P (type))
7122 /* Now that we've located the expression containing the value, it seems
7123 silly to make voidify_wrapper_expr repeat the process. Create a
7124 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7125 tmp = create_tmp_var_raw (type, NULL);
7127 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7128 tree_expr_nonnegative_p giving up immediately. */
7130 if (TREE_CODE (val) == NOP_EXPR
7131 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7132 val = TREE_OPERAND (val, 0);
7134 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7135 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7137 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7140 /* Begin and end compound statements. This is as simple as pushing
7141 and popping new statement lists from the tree. */
7144 c_begin_compound_stmt (bool do_scope)
7146 tree stmt = push_stmt_list ();
7153 c_end_compound_stmt (tree stmt, bool do_scope)
7159 if (c_dialect_objc ())
7160 objc_clear_super_receiver ();
7161 block = pop_scope ();
7164 stmt = pop_stmt_list (stmt);
7165 stmt = c_build_bind_expr (block, stmt);
7167 /* If this compound statement is nested immediately inside a statement
7168 expression, then force a BIND_EXPR to be created. Otherwise we'll
7169 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7170 STATEMENT_LISTs merge, and thus we can lose track of what statement
7173 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7174 && TREE_CODE (stmt) != BIND_EXPR)
7176 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7177 TREE_SIDE_EFFECTS (stmt) = 1;
7183 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7184 when the current scope is exited. EH_ONLY is true when this is not
7185 meant to apply to normal control flow transfer. */
7188 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7190 enum tree_code code;
7194 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7195 stmt = build_stmt (code, NULL, cleanup);
7197 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7198 list = push_stmt_list ();
7199 TREE_OPERAND (stmt, 0) = list;
7200 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7203 /* Build a binary-operation expression without default conversions.
7204 CODE is the kind of expression to build.
7205 This function differs from `build' in several ways:
7206 the data type of the result is computed and recorded in it,
7207 warnings are generated if arg data types are invalid,
7208 special handling for addition and subtraction of pointers is known,
7209 and some optimization is done (operations on narrow ints
7210 are done in the narrower type when that gives the same result).
7211 Constant folding is also done before the result is returned.
7213 Note that the operands will never have enumeral types, or function
7214 or array types, because either they will have the default conversions
7215 performed or they have both just been converted to some other type in which
7216 the arithmetic is to be done. */
7219 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7223 enum tree_code code0, code1;
7226 /* Expression code to give to the expression when it is built.
7227 Normally this is CODE, which is what the caller asked for,
7228 but in some special cases we change it. */
7229 enum tree_code resultcode = code;
7231 /* Data type in which the computation is to be performed.
7232 In the simplest cases this is the common type of the arguments. */
7233 tree result_type = NULL;
7235 /* Nonzero means operands have already been type-converted
7236 in whatever way is necessary.
7237 Zero means they need to be converted to RESULT_TYPE. */
7240 /* Nonzero means create the expression with this type, rather than
7242 tree build_type = 0;
7244 /* Nonzero means after finally constructing the expression
7245 convert it to this type. */
7246 tree final_type = 0;
7248 /* Nonzero if this is an operation like MIN or MAX which can
7249 safely be computed in short if both args are promoted shorts.
7250 Also implies COMMON.
7251 -1 indicates a bitwise operation; this makes a difference
7252 in the exact conditions for when it is safe to do the operation
7253 in a narrower mode. */
7256 /* Nonzero if this is a comparison operation;
7257 if both args are promoted shorts, compare the original shorts.
7258 Also implies COMMON. */
7259 int short_compare = 0;
7261 /* Nonzero if this is a right-shift operation, which can be computed on the
7262 original short and then promoted if the operand is a promoted short. */
7263 int short_shift = 0;
7265 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7270 op0 = default_conversion (orig_op0);
7271 op1 = default_conversion (orig_op1);
7279 type0 = TREE_TYPE (op0);
7280 type1 = TREE_TYPE (op1);
7282 /* The expression codes of the data types of the arguments tell us
7283 whether the arguments are integers, floating, pointers, etc. */
7284 code0 = TREE_CODE (type0);
7285 code1 = TREE_CODE (type1);
7287 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7288 STRIP_TYPE_NOPS (op0);
7289 STRIP_TYPE_NOPS (op1);
7291 /* If an error was already reported for one of the arguments,
7292 avoid reporting another error. */
7294 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7295 return error_mark_node;
7300 /* Handle the pointer + int case. */
7301 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7302 return pointer_int_sum (PLUS_EXPR, op0, op1);
7303 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7304 return pointer_int_sum (PLUS_EXPR, op1, op0);
7310 /* Subtraction of two similar pointers.
7311 We must subtract them as integers, then divide by object size. */
7312 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7313 && comp_target_types (type0, type1, 1))
7314 return pointer_diff (op0, op1);
7315 /* Handle pointer minus int. Just like pointer plus int. */
7316 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7317 return pointer_int_sum (MINUS_EXPR, op0, op1);
7326 case TRUNC_DIV_EXPR:
7328 case FLOOR_DIV_EXPR:
7329 case ROUND_DIV_EXPR:
7330 case EXACT_DIV_EXPR:
7331 /* Floating point division by zero is a legitimate way to obtain
7332 infinities and NaNs. */
7333 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7334 warning ("division by zero");
7336 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7337 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7338 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7339 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7341 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7342 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7343 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7344 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7346 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
7347 resultcode = RDIV_EXPR;
7349 /* Although it would be tempting to shorten always here, that
7350 loses on some targets, since the modulo instruction is
7351 undefined if the quotient can't be represented in the
7352 computation mode. We shorten only if unsigned or if
7353 dividing by something we know != -1. */
7354 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7355 || (TREE_CODE (op1) == INTEGER_CST
7356 && !integer_all_onesp (op1)));
7364 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7366 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7370 case TRUNC_MOD_EXPR:
7371 case FLOOR_MOD_EXPR:
7372 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7373 warning ("division by zero");
7375 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7377 /* Although it would be tempting to shorten always here, that loses
7378 on some targets, since the modulo instruction is undefined if the
7379 quotient can't be represented in the computation mode. We shorten
7380 only if unsigned or if dividing by something we know != -1. */
7381 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7382 || (TREE_CODE (op1) == INTEGER_CST
7383 && !integer_all_onesp (op1)));
7388 case TRUTH_ANDIF_EXPR:
7389 case TRUTH_ORIF_EXPR:
7390 case TRUTH_AND_EXPR:
7392 case TRUTH_XOR_EXPR:
7393 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7394 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7395 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7396 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7398 /* Result of these operations is always an int,
7399 but that does not mean the operands should be
7400 converted to ints! */
7401 result_type = integer_type_node;
7402 op0 = lang_hooks.truthvalue_conversion (op0);
7403 op1 = lang_hooks.truthvalue_conversion (op1);
7408 /* Shift operations: result has same type as first operand;
7409 always convert second operand to int.
7410 Also set SHORT_SHIFT if shifting rightward. */
7413 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7415 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7417 if (tree_int_cst_sgn (op1) < 0)
7418 warning ("right shift count is negative");
7421 if (!integer_zerop (op1))
7424 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7425 warning ("right shift count >= width of type");
7429 /* Use the type of the value to be shifted. */
7430 result_type = type0;
7431 /* Convert the shift-count to an integer, regardless of size
7432 of value being shifted. */
7433 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7434 op1 = convert (integer_type_node, op1);
7435 /* Avoid converting op1 to result_type later. */
7441 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7443 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7445 if (tree_int_cst_sgn (op1) < 0)
7446 warning ("left shift count is negative");
7448 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7449 warning ("left shift count >= width of type");
7452 /* Use the type of the value to be shifted. */
7453 result_type = type0;
7454 /* Convert the shift-count to an integer, regardless of size
7455 of value being shifted. */
7456 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7457 op1 = convert (integer_type_node, op1);
7458 /* Avoid converting op1 to result_type later. */
7465 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
7466 warning ("comparing floating point with == or != is unsafe");
7467 /* Result of comparison is always int,
7468 but don't convert the args to int! */
7469 build_type = integer_type_node;
7470 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7471 || code0 == COMPLEX_TYPE)
7472 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7473 || code1 == COMPLEX_TYPE))
7475 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7477 tree tt0 = TREE_TYPE (type0);
7478 tree tt1 = TREE_TYPE (type1);
7479 /* Anything compares with void *. void * compares with anything.
7480 Otherwise, the targets must be compatible
7481 and both must be object or both incomplete. */
7482 if (comp_target_types (type0, type1, 1))
7483 result_type = common_pointer_type (type0, type1);
7484 else if (VOID_TYPE_P (tt0))
7486 /* op0 != orig_op0 detects the case of something
7487 whose value is 0 but which isn't a valid null ptr const. */
7488 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7489 && TREE_CODE (tt1) == FUNCTION_TYPE)
7490 pedwarn ("ISO C forbids comparison of %<void *%>"
7491 " with function pointer");
7493 else if (VOID_TYPE_P (tt1))
7495 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7496 && TREE_CODE (tt0) == FUNCTION_TYPE)
7497 pedwarn ("ISO C forbids comparison of %<void *%>"
7498 " with function pointer");
7501 pedwarn ("comparison of distinct pointer types lacks a cast");
7503 if (result_type == NULL_TREE)
7504 result_type = ptr_type_node;
7506 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7507 && integer_zerop (op1))
7508 result_type = type0;
7509 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7510 && integer_zerop (op0))
7511 result_type = type1;
7512 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7514 result_type = type0;
7515 pedwarn ("comparison between pointer and integer");
7517 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7519 result_type = type1;
7520 pedwarn ("comparison between pointer and integer");
7528 build_type = integer_type_node;
7529 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7530 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7532 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7534 if (comp_target_types (type0, type1, 1))
7536 result_type = common_pointer_type (type0, type1);
7537 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7538 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7539 pedwarn ("comparison of complete and incomplete pointers");
7541 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7542 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7546 result_type = ptr_type_node;
7547 pedwarn ("comparison of distinct pointer types lacks a cast");
7550 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7551 && integer_zerop (op1))
7553 result_type = type0;
7554 if (pedantic || extra_warnings)
7555 pedwarn ("ordered comparison of pointer with integer zero");
7557 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7558 && integer_zerop (op0))
7560 result_type = type1;
7562 pedwarn ("ordered comparison of pointer with integer zero");
7564 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7566 result_type = type0;
7567 pedwarn ("comparison between pointer and integer");
7569 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7571 result_type = type1;
7572 pedwarn ("comparison between pointer and integer");
7580 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7581 return error_mark_node;
7583 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7584 || code0 == VECTOR_TYPE)
7586 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7587 || code1 == VECTOR_TYPE))
7589 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7591 if (shorten || common || short_compare)
7592 result_type = c_common_type (type0, type1);
7594 /* For certain operations (which identify themselves by shorten != 0)
7595 if both args were extended from the same smaller type,
7596 do the arithmetic in that type and then extend.
7598 shorten !=0 and !=1 indicates a bitwise operation.
7599 For them, this optimization is safe only if
7600 both args are zero-extended or both are sign-extended.
7601 Otherwise, we might change the result.
7602 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7603 but calculated in (unsigned short) it would be (unsigned short)-1. */
7605 if (shorten && none_complex)
7607 int unsigned0, unsigned1;
7608 tree arg0 = get_narrower (op0, &unsigned0);
7609 tree arg1 = get_narrower (op1, &unsigned1);
7610 /* UNS is 1 if the operation to be done is an unsigned one. */
7611 int uns = TYPE_UNSIGNED (result_type);
7614 final_type = result_type;
7616 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7617 but it *requires* conversion to FINAL_TYPE. */
7619 if ((TYPE_PRECISION (TREE_TYPE (op0))
7620 == TYPE_PRECISION (TREE_TYPE (arg0)))
7621 && TREE_TYPE (op0) != final_type)
7622 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7623 if ((TYPE_PRECISION (TREE_TYPE (op1))
7624 == TYPE_PRECISION (TREE_TYPE (arg1)))
7625 && TREE_TYPE (op1) != final_type)
7626 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7628 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7630 /* For bitwise operations, signedness of nominal type
7631 does not matter. Consider only how operands were extended. */
7635 /* Note that in all three cases below we refrain from optimizing
7636 an unsigned operation on sign-extended args.
7637 That would not be valid. */
7639 /* Both args variable: if both extended in same way
7640 from same width, do it in that width.
7641 Do it unsigned if args were zero-extended. */
7642 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7643 < TYPE_PRECISION (result_type))
7644 && (TYPE_PRECISION (TREE_TYPE (arg1))
7645 == TYPE_PRECISION (TREE_TYPE (arg0)))
7646 && unsigned0 == unsigned1
7647 && (unsigned0 || !uns))
7649 = c_common_signed_or_unsigned_type
7650 (unsigned0, c_common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7651 else if (TREE_CODE (arg0) == INTEGER_CST
7652 && (unsigned1 || !uns)
7653 && (TYPE_PRECISION (TREE_TYPE (arg1))
7654 < TYPE_PRECISION (result_type))
7656 = c_common_signed_or_unsigned_type (unsigned1,
7658 int_fits_type_p (arg0, type)))
7660 else if (TREE_CODE (arg1) == INTEGER_CST
7661 && (unsigned0 || !uns)
7662 && (TYPE_PRECISION (TREE_TYPE (arg0))
7663 < TYPE_PRECISION (result_type))
7665 = c_common_signed_or_unsigned_type (unsigned0,
7667 int_fits_type_p (arg1, type)))
7671 /* Shifts can be shortened if shifting right. */
7676 tree arg0 = get_narrower (op0, &unsigned_arg);
7678 final_type = result_type;
7680 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7681 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7683 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7684 /* We can shorten only if the shift count is less than the
7685 number of bits in the smaller type size. */
7686 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7687 /* We cannot drop an unsigned shift after sign-extension. */
7688 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7690 /* Do an unsigned shift if the operand was zero-extended. */
7692 = c_common_signed_or_unsigned_type (unsigned_arg,
7694 /* Convert value-to-be-shifted to that type. */
7695 if (TREE_TYPE (op0) != result_type)
7696 op0 = convert (result_type, op0);
7701 /* Comparison operations are shortened too but differently.
7702 They identify themselves by setting short_compare = 1. */
7706 /* Don't write &op0, etc., because that would prevent op0
7707 from being kept in a register.
7708 Instead, make copies of the our local variables and
7709 pass the copies by reference, then copy them back afterward. */
7710 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7711 enum tree_code xresultcode = resultcode;
7713 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7718 op0 = xop0, op1 = xop1;
7720 resultcode = xresultcode;
7722 if (warn_sign_compare && skip_evaluation == 0)
7724 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7725 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7726 int unsignedp0, unsignedp1;
7727 tree primop0 = get_narrower (op0, &unsignedp0);
7728 tree primop1 = get_narrower (op1, &unsignedp1);
7732 STRIP_TYPE_NOPS (xop0);
7733 STRIP_TYPE_NOPS (xop1);
7735 /* Give warnings for comparisons between signed and unsigned
7736 quantities that may fail.
7738 Do the checking based on the original operand trees, so that
7739 casts will be considered, but default promotions won't be.
7741 Do not warn if the comparison is being done in a signed type,
7742 since the signed type will only be chosen if it can represent
7743 all the values of the unsigned type. */
7744 if (!TYPE_UNSIGNED (result_type))
7746 /* Do not warn if both operands are the same signedness. */
7747 else if (op0_signed == op1_signed)
7754 sop = xop0, uop = xop1;
7756 sop = xop1, uop = xop0;
7758 /* Do not warn if the signed quantity is an
7759 unsuffixed integer literal (or some static
7760 constant expression involving such literals or a
7761 conditional expression involving such literals)
7762 and it is non-negative. */
7763 if (tree_expr_nonnegative_p (sop))
7765 /* Do not warn if the comparison is an equality operation,
7766 the unsigned quantity is an integral constant, and it
7767 would fit in the result if the result were signed. */
7768 else if (TREE_CODE (uop) == INTEGER_CST
7769 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
7771 (uop, c_common_signed_type (result_type)))
7773 /* Do not warn if the unsigned quantity is an enumeration
7774 constant and its maximum value would fit in the result
7775 if the result were signed. */
7776 else if (TREE_CODE (uop) == INTEGER_CST
7777 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
7779 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
7780 c_common_signed_type (result_type)))
7783 warning ("comparison between signed and unsigned");
7786 /* Warn if two unsigned values are being compared in a size
7787 larger than their original size, and one (and only one) is the
7788 result of a `~' operator. This comparison will always fail.
7790 Also warn if one operand is a constant, and the constant
7791 does not have all bits set that are set in the ~ operand
7792 when it is extended. */
7794 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
7795 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
7797 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
7798 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
7801 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
7804 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
7807 HOST_WIDE_INT constant, mask;
7808 int unsignedp, bits;
7810 if (host_integerp (primop0, 0))
7813 unsignedp = unsignedp1;
7814 constant = tree_low_cst (primop0, 0);
7819 unsignedp = unsignedp0;
7820 constant = tree_low_cst (primop1, 0);
7823 bits = TYPE_PRECISION (TREE_TYPE (primop));
7824 if (bits < TYPE_PRECISION (result_type)
7825 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
7827 mask = (~(HOST_WIDE_INT) 0) << bits;
7828 if ((mask & constant) != mask)
7829 warning ("comparison of promoted ~unsigned with constant");
7832 else if (unsignedp0 && unsignedp1
7833 && (TYPE_PRECISION (TREE_TYPE (primop0))
7834 < TYPE_PRECISION (result_type))
7835 && (TYPE_PRECISION (TREE_TYPE (primop1))
7836 < TYPE_PRECISION (result_type)))
7837 warning ("comparison of promoted ~unsigned with unsigned");
7843 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
7844 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
7845 Then the expression will be built.
7846 It will be given type FINAL_TYPE if that is nonzero;
7847 otherwise, it will be given type RESULT_TYPE. */
7851 binary_op_error (code);
7852 return error_mark_node;
7857 if (TREE_TYPE (op0) != result_type)
7858 op0 = convert (result_type, op0);
7859 if (TREE_TYPE (op1) != result_type)
7860 op1 = convert (result_type, op1);
7862 /* This can happen if one operand has a vector type, and the other
7863 has a different type. */
7864 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
7865 return error_mark_node;
7868 if (build_type == NULL_TREE)
7869 build_type = result_type;
7872 tree result = build2 (resultcode, build_type, op0, op1);
7874 /* Treat expressions in initializers specially as they can't trap. */
7875 result = require_constant_value ? fold_initializer (result)
7878 if (final_type != 0)
7879 result = convert (final_type, result);