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_se *label_context_stack_se;
68 struct c_label_context_vm *label_context_stack_vm;
70 /* Nonzero if we've already printed a "missing braces around initializer"
71 message within this initializer. */
72 static int missing_braces_mentioned;
74 static int require_constant_value;
75 static int require_constant_elements;
77 static tree qualify_type (tree, tree);
78 static int tagged_types_tu_compatible_p (tree, tree);
79 static int comp_target_types (tree, tree, int);
80 static int function_types_compatible_p (tree, tree);
81 static int type_lists_compatible_p (tree, tree);
82 static tree decl_constant_value_for_broken_optimization (tree);
83 static tree default_function_array_conversion (tree);
84 static tree lookup_field (tree, tree);
85 static tree convert_arguments (tree, tree, tree, tree);
86 static tree pointer_diff (tree, tree);
87 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 static tree valid_compound_expr_initializer (tree, tree);
90 static void push_string (const char *);
91 static void push_member_name (tree);
92 static void push_array_bounds (int);
93 static int spelling_length (void);
94 static char *print_spelling (char *);
95 static void warning_init (const char *);
96 static tree digest_init (tree, tree, bool, int);
97 static void output_init_element (tree, bool, tree, tree, int);
98 static void output_pending_init_elements (int);
99 static int set_designator (int);
100 static void push_range_stack (tree);
101 static void add_pending_init (tree, tree);
102 static void set_nonincremental_init (void);
103 static void set_nonincremental_init_from_string (tree);
104 static tree find_init_member (tree);
105 static void readonly_error (tree, enum lvalue_use);
106 static int lvalue_or_else (tree, enum lvalue_use);
107 static int lvalue_p (tree);
108 static void record_maybe_used_decl (tree);
110 /* Do `exp = require_complete_type (exp);' to make sure exp
111 does not have an incomplete type. (That includes void types.) */
114 require_complete_type (tree value)
116 tree type = TREE_TYPE (value);
118 if (value == error_mark_node || type == error_mark_node)
119 return error_mark_node;
121 /* First, detect a valid value with a complete type. */
122 if (COMPLETE_TYPE_P (type))
125 c_incomplete_type_error (value, type);
126 return error_mark_node;
129 /* Print an error message for invalid use of an incomplete type.
130 VALUE is the expression that was used (or 0 if that isn't known)
131 and TYPE is the type that was invalid. */
134 c_incomplete_type_error (tree value, tree type)
136 const char *type_code_string;
138 /* Avoid duplicate error message. */
139 if (TREE_CODE (type) == ERROR_MARK)
142 if (value != 0 && (TREE_CODE (value) == VAR_DECL
143 || TREE_CODE (value) == PARM_DECL))
144 error ("%qD has an incomplete type", value);
148 /* We must print an error message. Be clever about what it says. */
150 switch (TREE_CODE (type))
153 type_code_string = "struct";
157 type_code_string = "union";
161 type_code_string = "enum";
165 error ("invalid use of void expression");
169 if (TYPE_DOMAIN (type))
171 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
173 error ("invalid use of flexible array member");
176 type = TREE_TYPE (type);
179 error ("invalid use of array with unspecified bounds");
186 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
187 error ("invalid use of undefined type %<%s %E%>",
188 type_code_string, TYPE_NAME (type));
190 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
191 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
195 /* Given a type, apply default promotions wrt unnamed function
196 arguments and return the new type. */
199 c_type_promotes_to (tree type)
201 if (TYPE_MAIN_VARIANT (type) == float_type_node)
202 return double_type_node;
204 if (c_promoting_integer_type_p (type))
206 /* Preserve unsignedness if not really getting any wider. */
207 if (TYPE_UNSIGNED (type)
208 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
209 return unsigned_type_node;
210 return integer_type_node;
216 /* Return a variant of TYPE which has all the type qualifiers of LIKE
217 as well as those of TYPE. */
220 qualify_type (tree type, tree like)
222 return c_build_qualified_type (type,
223 TYPE_QUALS (type) | TYPE_QUALS (like));
226 /* Return the composite type of two compatible types.
228 We assume that comptypes has already been done and returned
229 nonzero; if that isn't so, this may crash. In particular, we
230 assume that qualifiers match. */
233 composite_type (tree t1, tree t2)
235 enum tree_code code1;
236 enum tree_code code2;
239 /* Save time if the two types are the same. */
241 if (t1 == t2) return t1;
243 /* If one type is nonsense, use the other. */
244 if (t1 == error_mark_node)
246 if (t2 == error_mark_node)
249 code1 = TREE_CODE (t1);
250 code2 = TREE_CODE (t2);
252 /* Merge the attributes. */
253 attributes = targetm.merge_type_attributes (t1, t2);
255 /* If one is an enumerated type and the other is the compatible
256 integer type, the composite type might be either of the two
257 (DR#013 question 3). For consistency, use the enumerated type as
258 the composite type. */
260 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
262 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
265 gcc_assert (code1 == code2);
270 /* For two pointers, do this recursively on the target type. */
272 tree pointed_to_1 = TREE_TYPE (t1);
273 tree pointed_to_2 = TREE_TYPE (t2);
274 tree target = composite_type (pointed_to_1, pointed_to_2);
275 t1 = build_pointer_type (target);
276 t1 = build_type_attribute_variant (t1, attributes);
277 return qualify_type (t1, t2);
282 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
286 /* We should not have any type quals on arrays at all. */
287 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
289 /* Save space: see if the result is identical to one of the args. */
290 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
291 return build_type_attribute_variant (t1, attributes);
292 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
293 return build_type_attribute_variant (t2, attributes);
295 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
296 return build_type_attribute_variant (t1, attributes);
297 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
298 return build_type_attribute_variant (t2, attributes);
300 /* Merge the element types, and have a size if either arg has
301 one. We may have qualifiers on the element types. To set
302 up TYPE_MAIN_VARIANT correctly, we need to form the
303 composite of the unqualified types and add the qualifiers
305 quals = TYPE_QUALS (strip_array_types (elt));
306 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
307 t1 = build_array_type (unqual_elt,
308 TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
309 t1 = c_build_qualified_type (t1, quals);
310 return build_type_attribute_variant (t1, attributes);
314 /* Function types: prefer the one that specified arg types.
315 If both do, merge the arg types. Also merge the return types. */
317 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
318 tree p1 = TYPE_ARG_TYPES (t1);
319 tree p2 = TYPE_ARG_TYPES (t2);
324 /* Save space: see if the result is identical to one of the args. */
325 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
326 return build_type_attribute_variant (t1, attributes);
327 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
328 return build_type_attribute_variant (t2, attributes);
330 /* Simple way if one arg fails to specify argument types. */
331 if (TYPE_ARG_TYPES (t1) == 0)
333 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
334 t1 = build_type_attribute_variant (t1, attributes);
335 return qualify_type (t1, t2);
337 if (TYPE_ARG_TYPES (t2) == 0)
339 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
340 t1 = build_type_attribute_variant (t1, attributes);
341 return qualify_type (t1, t2);
344 /* If both args specify argument types, we must merge the two
345 lists, argument by argument. */
346 /* Tell global_bindings_p to return false so that variable_size
347 doesn't die on VLAs in parameter types. */
348 c_override_global_bindings_to_false = true;
350 len = list_length (p1);
353 for (i = 0; i < len; i++)
354 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
359 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
361 /* A null type means arg type is not specified.
362 Take whatever the other function type has. */
363 if (TREE_VALUE (p1) == 0)
365 TREE_VALUE (n) = TREE_VALUE (p2);
368 if (TREE_VALUE (p2) == 0)
370 TREE_VALUE (n) = TREE_VALUE (p1);
374 /* Given wait (union {union wait *u; int *i} *)
375 and wait (union wait *),
376 prefer union wait * as type of parm. */
377 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
378 && TREE_VALUE (p1) != TREE_VALUE (p2))
381 tree mv2 = TREE_VALUE (p2);
382 if (mv2 && mv2 != error_mark_node
383 && TREE_CODE (mv2) != ARRAY_TYPE)
384 mv2 = TYPE_MAIN_VARIANT (mv2);
385 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
386 memb; memb = TREE_CHAIN (memb))
388 tree mv3 = TREE_TYPE (memb);
389 if (mv3 && mv3 != error_mark_node
390 && TREE_CODE (mv3) != ARRAY_TYPE)
391 mv3 = TYPE_MAIN_VARIANT (mv3);
392 if (comptypes (mv3, mv2))
394 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
397 pedwarn ("function types not truly compatible in ISO C");
402 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
403 && TREE_VALUE (p2) != TREE_VALUE (p1))
406 tree mv1 = TREE_VALUE (p1);
407 if (mv1 && mv1 != error_mark_node
408 && TREE_CODE (mv1) != ARRAY_TYPE)
409 mv1 = TYPE_MAIN_VARIANT (mv1);
410 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
411 memb; memb = TREE_CHAIN (memb))
413 tree mv3 = TREE_TYPE (memb);
414 if (mv3 && mv3 != error_mark_node
415 && TREE_CODE (mv3) != ARRAY_TYPE)
416 mv3 = TYPE_MAIN_VARIANT (mv3);
417 if (comptypes (mv3, mv1))
419 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
422 pedwarn ("function types not truly compatible in ISO C");
427 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
431 c_override_global_bindings_to_false = false;
432 t1 = build_function_type (valtype, newargs);
433 t1 = qualify_type (t1, t2);
434 /* ... falls through ... */
438 return build_type_attribute_variant (t1, attributes);
443 /* Return the type of a conditional expression between pointers to
444 possibly differently qualified versions of compatible types.
446 We assume that comp_target_types has already been done and returned
447 nonzero; if that isn't so, this may crash. */
450 common_pointer_type (tree t1, tree t2)
453 tree pointed_to_1, mv1;
454 tree pointed_to_2, mv2;
457 /* Save time if the two types are the same. */
459 if (t1 == t2) return t1;
461 /* If one type is nonsense, use the other. */
462 if (t1 == error_mark_node)
464 if (t2 == error_mark_node)
467 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
468 && TREE_CODE (t2) == POINTER_TYPE);
470 /* Merge the attributes. */
471 attributes = targetm.merge_type_attributes (t1, t2);
473 /* Find the composite type of the target types, and combine the
474 qualifiers of the two types' targets. Do not lose qualifiers on
475 array element types by taking the TYPE_MAIN_VARIANT. */
476 mv1 = pointed_to_1 = TREE_TYPE (t1);
477 mv2 = pointed_to_2 = TREE_TYPE (t2);
478 if (TREE_CODE (mv1) != ARRAY_TYPE)
479 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
480 if (TREE_CODE (mv2) != ARRAY_TYPE)
481 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
482 target = composite_type (mv1, mv2);
483 t1 = build_pointer_type (c_build_qualified_type
485 TYPE_QUALS (pointed_to_1) |
486 TYPE_QUALS (pointed_to_2)));
487 return build_type_attribute_variant (t1, attributes);
490 /* Return the common type for two arithmetic types under the usual
491 arithmetic conversions. The default conversions have already been
492 applied, and enumerated types converted to their compatible integer
493 types. The resulting type is unqualified and has no attributes.
495 This is the type for the result of most arithmetic operations
496 if the operands have the given two types. */
499 c_common_type (tree t1, tree t2)
501 enum tree_code code1;
502 enum tree_code code2;
504 /* If one type is nonsense, use the other. */
505 if (t1 == error_mark_node)
507 if (t2 == error_mark_node)
510 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
511 t1 = TYPE_MAIN_VARIANT (t1);
513 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
514 t2 = TYPE_MAIN_VARIANT (t2);
516 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
517 t1 = build_type_attribute_variant (t1, NULL_TREE);
519 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
520 t2 = build_type_attribute_variant (t2, NULL_TREE);
522 /* Save time if the two types are the same. */
524 if (t1 == t2) return t1;
526 code1 = TREE_CODE (t1);
527 code2 = TREE_CODE (t2);
529 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
530 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
531 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
532 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
534 /* If one type is a vector type, return that type. (How the usual
535 arithmetic conversions apply to the vector types extension is not
536 precisely specified.) */
537 if (code1 == VECTOR_TYPE)
540 if (code2 == VECTOR_TYPE)
543 /* If one type is complex, form the common type of the non-complex
544 components, then make that complex. Use T1 or T2 if it is the
546 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
548 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
549 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
550 tree subtype = c_common_type (subtype1, subtype2);
552 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
554 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
557 return build_complex_type (subtype);
560 /* If only one is real, use it as the result. */
562 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
565 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
568 /* Both real or both integers; use the one with greater precision. */
570 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
572 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
575 /* Same precision. Prefer long longs to longs to ints when the
576 same precision, following the C99 rules on integer type rank
577 (which are equivalent to the C90 rules for C90 types). */
579 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
580 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
581 return long_long_unsigned_type_node;
583 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
584 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
586 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
587 return long_long_unsigned_type_node;
589 return long_long_integer_type_node;
592 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
593 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
594 return long_unsigned_type_node;
596 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
597 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
599 /* But preserve unsignedness from the other type,
600 since long cannot hold all the values of an unsigned int. */
601 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
602 return long_unsigned_type_node;
604 return long_integer_type_node;
607 /* Likewise, prefer long double to double even if same size. */
608 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
609 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
610 return long_double_type_node;
612 /* Otherwise prefer the unsigned one. */
614 if (TYPE_UNSIGNED (t1))
620 /* Wrapper around c_common_type that is used by c-common.c. ENUMERAL_TYPEs
621 are allowed here and are converted to their compatible integer types.
622 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
623 preferably a non-Boolean type as the common type. */
625 common_type (tree t1, tree t2)
627 if (TREE_CODE (t1) == ENUMERAL_TYPE)
628 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
629 if (TREE_CODE (t2) == ENUMERAL_TYPE)
630 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
632 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
633 if (TREE_CODE (t1) == BOOLEAN_TYPE
634 && TREE_CODE (t2) == BOOLEAN_TYPE)
635 return boolean_type_node;
637 /* If either type is BOOLEAN_TYPE, then return the other. */
638 if (TREE_CODE (t1) == BOOLEAN_TYPE)
640 if (TREE_CODE (t2) == BOOLEAN_TYPE)
643 return c_common_type (t1, t2);
646 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
647 or various other operations. Return 2 if they are compatible
648 but a warning may be needed if you use them together. */
651 comptypes (tree type1, tree type2)
657 /* Suppress errors caused by previously reported errors. */
659 if (t1 == t2 || !t1 || !t2
660 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
663 /* If either type is the internal version of sizetype, return the
665 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
666 && TYPE_ORIG_SIZE_TYPE (t1))
667 t1 = TYPE_ORIG_SIZE_TYPE (t1);
669 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
670 && TYPE_ORIG_SIZE_TYPE (t2))
671 t2 = TYPE_ORIG_SIZE_TYPE (t2);
674 /* Enumerated types are compatible with integer types, but this is
675 not transitive: two enumerated types in the same translation unit
676 are compatible with each other only if they are the same type. */
678 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
679 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
680 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
681 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
686 /* Different classes of types can't be compatible. */
688 if (TREE_CODE (t1) != TREE_CODE (t2))
691 /* Qualifiers must match. C99 6.7.3p9 */
693 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
696 /* Allow for two different type nodes which have essentially the same
697 definition. Note that we already checked for equality of the type
698 qualifiers (just above). */
700 if (TREE_CODE (t1) != ARRAY_TYPE
701 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
704 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
705 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
708 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
711 switch (TREE_CODE (t1))
714 /* We must give ObjC the first crack at comparing pointers, since
715 protocol qualifiers may be involved. */
716 if (c_dialect_objc () && (val = objc_comptypes (t1, t2, 0)) >= 0)
718 /* Do not remove mode or aliasing information. */
719 if (TYPE_MODE (t1) != TYPE_MODE (t2)
720 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
722 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
723 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
727 val = function_types_compatible_p (t1, t2);
732 tree d1 = TYPE_DOMAIN (t1);
733 tree d2 = TYPE_DOMAIN (t2);
734 bool d1_variable, d2_variable;
735 bool d1_zero, d2_zero;
738 /* Target types must match incl. qualifiers. */
739 if (TREE_TYPE (t1) != TREE_TYPE (t2)
740 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
743 /* Sizes must match unless one is missing or variable. */
744 if (d1 == 0 || d2 == 0 || d1 == d2)
747 d1_zero = !TYPE_MAX_VALUE (d1);
748 d2_zero = !TYPE_MAX_VALUE (d2);
750 d1_variable = (!d1_zero
751 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
752 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
753 d2_variable = (!d2_zero
754 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
755 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
757 if (d1_variable || d2_variable)
759 if (d1_zero && d2_zero)
761 if (d1_zero || d2_zero
762 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
763 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
770 /* We are dealing with two distinct structs. In assorted Objective-C
771 corner cases, however, these can still be deemed equivalent. */
772 if (c_dialect_objc () && objc_comptypes (t1, t2, 0) == 1)
777 if (val != 1 && !same_translation_unit_p (t1, t2))
778 val = tagged_types_tu_compatible_p (t1, t2);
782 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
783 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2));
789 return attrval == 2 && val == 1 ? 2 : val;
792 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
793 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
794 to 1 or 0 depending if the check of the pointer types is meant to
795 be reflexive or not (typically, assignments are not reflexive,
796 while comparisons are reflexive).
800 comp_target_types (tree ttl, tree ttr, int reflexive)
805 /* Give objc_comptypes a crack at letting these types through. */
806 if ((val = objc_comptypes (ttl, ttr, reflexive)) >= 0)
809 /* Do not lose qualifiers on element types of array types that are
810 pointer targets by taking their TYPE_MAIN_VARIANT. */
811 mvl = TREE_TYPE (ttl);
812 mvr = TREE_TYPE (ttr);
813 if (TREE_CODE (mvl) != ARRAY_TYPE)
814 mvl = TYPE_MAIN_VARIANT (mvl);
815 if (TREE_CODE (mvr) != ARRAY_TYPE)
816 mvr = TYPE_MAIN_VARIANT (mvr);
817 val = comptypes (mvl, mvr);
819 if (val == 2 && pedantic)
820 pedwarn ("types are not quite compatible");
824 /* Subroutines of `comptypes'. */
826 /* Determine whether two trees derive from the same translation unit.
827 If the CONTEXT chain ends in a null, that tree's context is still
828 being parsed, so if two trees have context chains ending in null,
829 they're in the same translation unit. */
831 same_translation_unit_p (tree t1, tree t2)
833 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
834 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
836 case tcc_declaration:
837 t1 = DECL_CONTEXT (t1); break;
839 t1 = TYPE_CONTEXT (t1); break;
840 case tcc_exceptional:
841 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
842 default: gcc_unreachable ();
845 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
846 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
848 case tcc_declaration:
849 t2 = DECL_CONTEXT (t2); break;
851 t2 = TYPE_CONTEXT (t2); break;
852 case tcc_exceptional:
853 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
854 default: gcc_unreachable ();
860 /* The C standard says that two structures in different translation
861 units are compatible with each other only if the types of their
862 fields are compatible (among other things). So, consider two copies
863 of this structure: */
865 struct tagged_tu_seen {
866 const struct tagged_tu_seen * next;
871 /* Can they be compatible with each other? We choose to break the
872 recursion by allowing those types to be compatible. */
874 static const struct tagged_tu_seen * tagged_tu_seen_base;
876 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
877 compatible. If the two types are not the same (which has been
878 checked earlier), this can only happen when multiple translation
879 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
883 tagged_types_tu_compatible_p (tree t1, tree t2)
886 bool needs_warning = false;
888 /* We have to verify that the tags of the types are the same. This
889 is harder than it looks because this may be a typedef, so we have
890 to go look at the original type. It may even be a typedef of a
892 In the case of compiler-created builtin structs the TYPE_DECL
893 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
894 while (TYPE_NAME (t1)
895 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
896 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
897 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
899 while (TYPE_NAME (t2)
900 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
901 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
902 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
904 /* C90 didn't have the requirement that the two tags be the same. */
905 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
908 /* C90 didn't say what happened if one or both of the types were
909 incomplete; we choose to follow C99 rules here, which is that they
911 if (TYPE_SIZE (t1) == NULL
912 || TYPE_SIZE (t2) == NULL)
916 const struct tagged_tu_seen * tts_i;
917 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
918 if (tts_i->t1 == t1 && tts_i->t2 == t2)
922 switch (TREE_CODE (t1))
927 /* Speed up the case where the type values are in the same order. */
928 tree tv1 = TYPE_VALUES (t1);
929 tree tv2 = TYPE_VALUES (t2);
934 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
936 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
938 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
942 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
944 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
947 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
950 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
952 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
954 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
962 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
965 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
968 struct tagged_tu_seen tts;
970 tts.next = tagged_tu_seen_base;
973 tagged_tu_seen_base = &tts;
975 if (DECL_NAME (s1) != NULL)
976 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
977 if (DECL_NAME (s1) == DECL_NAME (s2))
980 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
984 needs_warning = true;
986 if (TREE_CODE (s1) == FIELD_DECL
987 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
988 DECL_FIELD_BIT_OFFSET (s2)) != 1)
994 tagged_tu_seen_base = tts.next;
998 return needs_warning ? 2 : 1;
1003 struct tagged_tu_seen tts;
1005 tts.next = tagged_tu_seen_base;
1008 tagged_tu_seen_base = &tts;
1010 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1012 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1015 if (TREE_CODE (s1) != TREE_CODE (s2)
1016 || DECL_NAME (s1) != DECL_NAME (s2))
1018 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
1022 needs_warning = true;
1024 if (TREE_CODE (s1) == FIELD_DECL
1025 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1026 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1029 tagged_tu_seen_base = tts.next;
1032 return needs_warning ? 2 : 1;
1040 /* Return 1 if two function types F1 and F2 are compatible.
1041 If either type specifies no argument types,
1042 the other must specify a fixed number of self-promoting arg types.
1043 Otherwise, if one type specifies only the number of arguments,
1044 the other must specify that number of self-promoting arg types.
1045 Otherwise, the argument types must match. */
1048 function_types_compatible_p (tree f1, tree f2)
1051 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1056 ret1 = TREE_TYPE (f1);
1057 ret2 = TREE_TYPE (f2);
1059 /* 'volatile' qualifiers on a function's return type used to mean
1060 the function is noreturn. */
1061 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1062 pedwarn ("function return types not compatible due to %<volatile%>");
1063 if (TYPE_VOLATILE (ret1))
1064 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1065 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1066 if (TYPE_VOLATILE (ret2))
1067 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1068 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1069 val = comptypes (ret1, ret2);
1073 args1 = TYPE_ARG_TYPES (f1);
1074 args2 = TYPE_ARG_TYPES (f2);
1076 /* An unspecified parmlist matches any specified parmlist
1077 whose argument types don't need default promotions. */
1081 if (!self_promoting_args_p (args2))
1083 /* If one of these types comes from a non-prototype fn definition,
1084 compare that with the other type's arglist.
1085 If they don't match, ask for a warning (0, but no error). */
1086 if (TYPE_ACTUAL_ARG_TYPES (f1)
1087 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1093 if (!self_promoting_args_p (args1))
1095 if (TYPE_ACTUAL_ARG_TYPES (f2)
1096 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1101 /* Both types have argument lists: compare them and propagate results. */
1102 val1 = type_lists_compatible_p (args1, args2);
1103 return val1 != 1 ? val1 : val;
1106 /* Check two lists of types for compatibility,
1107 returning 0 for incompatible, 1 for compatible,
1108 or 2 for compatible with warning. */
1111 type_lists_compatible_p (tree args1, tree args2)
1113 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1119 tree a1, mv1, a2, mv2;
1120 if (args1 == 0 && args2 == 0)
1122 /* If one list is shorter than the other,
1123 they fail to match. */
1124 if (args1 == 0 || args2 == 0)
1126 mv1 = a1 = TREE_VALUE (args1);
1127 mv2 = a2 = TREE_VALUE (args2);
1128 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1129 mv1 = TYPE_MAIN_VARIANT (mv1);
1130 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1131 mv2 = TYPE_MAIN_VARIANT (mv2);
1132 /* A null pointer instead of a type
1133 means there is supposed to be an argument
1134 but nothing is specified about what type it has.
1135 So match anything that self-promotes. */
1138 if (c_type_promotes_to (a2) != a2)
1143 if (c_type_promotes_to (a1) != a1)
1146 /* If one of the lists has an error marker, ignore this arg. */
1147 else if (TREE_CODE (a1) == ERROR_MARK
1148 || TREE_CODE (a2) == ERROR_MARK)
1150 else if (!(newval = comptypes (mv1, mv2)))
1152 /* Allow wait (union {union wait *u; int *i} *)
1153 and wait (union wait *) to be compatible. */
1154 if (TREE_CODE (a1) == UNION_TYPE
1155 && (TYPE_NAME (a1) == 0
1156 || TYPE_TRANSPARENT_UNION (a1))
1157 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1158 && tree_int_cst_equal (TYPE_SIZE (a1),
1162 for (memb = TYPE_FIELDS (a1);
1163 memb; memb = TREE_CHAIN (memb))
1165 tree mv3 = TREE_TYPE (memb);
1166 if (mv3 && mv3 != error_mark_node
1167 && TREE_CODE (mv3) != ARRAY_TYPE)
1168 mv3 = TYPE_MAIN_VARIANT (mv3);
1169 if (comptypes (mv3, mv2))
1175 else if (TREE_CODE (a2) == UNION_TYPE
1176 && (TYPE_NAME (a2) == 0
1177 || TYPE_TRANSPARENT_UNION (a2))
1178 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1179 && tree_int_cst_equal (TYPE_SIZE (a2),
1183 for (memb = TYPE_FIELDS (a2);
1184 memb; memb = TREE_CHAIN (memb))
1186 tree mv3 = TREE_TYPE (memb);
1187 if (mv3 && mv3 != error_mark_node
1188 && TREE_CODE (mv3) != ARRAY_TYPE)
1189 mv3 = TYPE_MAIN_VARIANT (mv3);
1190 if (comptypes (mv3, mv1))
1200 /* comptypes said ok, but record if it said to warn. */
1204 args1 = TREE_CHAIN (args1);
1205 args2 = TREE_CHAIN (args2);
1209 /* Compute the size to increment a pointer by. */
1212 c_size_in_bytes (tree type)
1214 enum tree_code code = TREE_CODE (type);
1216 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1217 return size_one_node;
1219 if (!COMPLETE_OR_VOID_TYPE_P (type))
1221 error ("arithmetic on pointer to an incomplete type");
1222 return size_one_node;
1225 /* Convert in case a char is more than one unit. */
1226 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1227 size_int (TYPE_PRECISION (char_type_node)
1231 /* Return either DECL or its known constant value (if it has one). */
1234 decl_constant_value (tree decl)
1236 if (/* Don't change a variable array bound or initial value to a constant
1237 in a place where a variable is invalid. Note that DECL_INITIAL
1238 isn't valid for a PARM_DECL. */
1239 current_function_decl != 0
1240 && TREE_CODE (decl) != PARM_DECL
1241 && !TREE_THIS_VOLATILE (decl)
1242 && TREE_READONLY (decl)
1243 && DECL_INITIAL (decl) != 0
1244 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1245 /* This is invalid if initial value is not constant.
1246 If it has either a function call, a memory reference,
1247 or a variable, then re-evaluating it could give different results. */
1248 && TREE_CONSTANT (DECL_INITIAL (decl))
1249 /* Check for cases where this is sub-optimal, even though valid. */
1250 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1251 return DECL_INITIAL (decl);
1255 /* Return either DECL or its known constant value (if it has one), but
1256 return DECL if pedantic or DECL has mode BLKmode. This is for
1257 bug-compatibility with the old behavior of decl_constant_value
1258 (before GCC 3.0); every use of this function is a bug and it should
1259 be removed before GCC 3.1. It is not appropriate to use pedantic
1260 in a way that affects optimization, and BLKmode is probably not the
1261 right test for avoiding misoptimizations either. */
1264 decl_constant_value_for_broken_optimization (tree decl)
1268 if (pedantic || DECL_MODE (decl) == BLKmode)
1271 ret = decl_constant_value (decl);
1272 /* Avoid unwanted tree sharing between the initializer and current
1273 function's body where the tree can be modified e.g. by the
1275 if (ret != decl && TREE_STATIC (decl))
1276 ret = unshare_expr (ret);
1281 /* Perform the default conversion of arrays and functions to pointers.
1282 Return the result of converting EXP. For any other expression, just
1286 default_function_array_conversion (tree exp)
1289 tree type = TREE_TYPE (exp);
1290 enum tree_code code = TREE_CODE (type);
1293 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1296 Do not use STRIP_NOPS here! It will remove conversions from pointer
1297 to integer and cause infinite recursion. */
1299 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1300 || (TREE_CODE (exp) == NOP_EXPR
1301 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1303 if (TREE_CODE (exp) == NON_LVALUE_EXPR)
1305 exp = TREE_OPERAND (exp, 0);
1308 if (TREE_NO_WARNING (orig_exp))
1309 TREE_NO_WARNING (exp) = 1;
1311 if (code == FUNCTION_TYPE)
1313 return build_unary_op (ADDR_EXPR, exp, 0);
1315 if (code == ARRAY_TYPE)
1318 tree restype = TREE_TYPE (type);
1324 if (REFERENCE_CLASS_P (exp) || DECL_P (exp))
1326 constp = TREE_READONLY (exp);
1327 volatilep = TREE_THIS_VOLATILE (exp);
1330 if (TYPE_QUALS (type) || constp || volatilep)
1332 = c_build_qualified_type (restype,
1334 | (constp * TYPE_QUAL_CONST)
1335 | (volatilep * TYPE_QUAL_VOLATILE));
1337 if (TREE_CODE (exp) == INDIRECT_REF)
1338 return convert (build_pointer_type (restype),
1339 TREE_OPERAND (exp, 0));
1341 if (TREE_CODE (exp) == COMPOUND_EXPR)
1343 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1344 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1345 TREE_OPERAND (exp, 0), op1);
1348 lvalue_array_p = !not_lvalue && lvalue_p (exp);
1349 if (!flag_isoc99 && !lvalue_array_p)
1351 /* Before C99, non-lvalue arrays do not decay to pointers.
1352 Normally, using such an array would be invalid; but it can
1353 be used correctly inside sizeof or as a statement expression.
1354 Thus, do not give an error here; an error will result later. */
1358 ptrtype = build_pointer_type (restype);
1360 if (TREE_CODE (exp) == VAR_DECL)
1362 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1363 ADDR_EXPR because it's the best way of representing what
1364 happens in C when we take the address of an array and place
1365 it in a pointer to the element type. */
1366 adr = build1 (ADDR_EXPR, ptrtype, exp);
1367 if (!c_mark_addressable (exp))
1368 return error_mark_node;
1369 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1372 /* This way is better for a COMPONENT_REF since it can
1373 simplify the offset for a component. */
1374 adr = build_unary_op (ADDR_EXPR, exp, 1);
1375 return convert (ptrtype, adr);
1381 /* EXP is an expression of integer type. Apply the integer promotions
1382 to it and return the promoted value. */
1385 perform_integral_promotions (tree exp)
1387 tree type = TREE_TYPE (exp);
1388 enum tree_code code = TREE_CODE (type);
1390 gcc_assert (INTEGRAL_TYPE_P (type));
1392 /* Normally convert enums to int,
1393 but convert wide enums to something wider. */
1394 if (code == ENUMERAL_TYPE)
1396 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1397 TYPE_PRECISION (integer_type_node)),
1398 ((TYPE_PRECISION (type)
1399 >= TYPE_PRECISION (integer_type_node))
1400 && TYPE_UNSIGNED (type)));
1402 return convert (type, exp);
1405 /* ??? This should no longer be needed now bit-fields have their
1407 if (TREE_CODE (exp) == COMPONENT_REF
1408 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1409 /* If it's thinner than an int, promote it like a
1410 c_promoting_integer_type_p, otherwise leave it alone. */
1411 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1412 TYPE_PRECISION (integer_type_node)))
1413 return convert (integer_type_node, exp);
1415 if (c_promoting_integer_type_p (type))
1417 /* Preserve unsignedness if not really getting any wider. */
1418 if (TYPE_UNSIGNED (type)
1419 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1420 return convert (unsigned_type_node, exp);
1422 return convert (integer_type_node, exp);
1429 /* Perform default promotions for C data used in expressions.
1430 Arrays and functions are converted to pointers;
1431 enumeral types or short or char, to int.
1432 In addition, manifest constants symbols are replaced by their values. */
1435 default_conversion (tree exp)
1438 tree type = TREE_TYPE (exp);
1439 enum tree_code code = TREE_CODE (type);
1441 if (code == FUNCTION_TYPE || code == ARRAY_TYPE)
1442 return default_function_array_conversion (exp);
1444 /* Constants can be used directly unless they're not loadable. */
1445 if (TREE_CODE (exp) == CONST_DECL)
1446 exp = DECL_INITIAL (exp);
1448 /* Replace a nonvolatile const static variable with its value unless
1449 it is an array, in which case we must be sure that taking the
1450 address of the array produces consistent results. */
1451 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1453 exp = decl_constant_value_for_broken_optimization (exp);
1454 type = TREE_TYPE (exp);
1457 /* Strip no-op conversions. */
1459 STRIP_TYPE_NOPS (exp);
1461 if (TREE_NO_WARNING (orig_exp))
1462 TREE_NO_WARNING (exp) = 1;
1464 if (INTEGRAL_TYPE_P (type))
1465 return perform_integral_promotions (exp);
1467 if (code == VOID_TYPE)
1469 error ("void value not ignored as it ought to be");
1470 return error_mark_node;
1475 /* Look up COMPONENT in a structure or union DECL.
1477 If the component name is not found, returns NULL_TREE. Otherwise,
1478 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1479 stepping down the chain to the component, which is in the last
1480 TREE_VALUE of the list. Normally the list is of length one, but if
1481 the component is embedded within (nested) anonymous structures or
1482 unions, the list steps down the chain to the component. */
1485 lookup_field (tree decl, tree component)
1487 tree type = TREE_TYPE (decl);
1490 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1491 to the field elements. Use a binary search on this array to quickly
1492 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1493 will always be set for structures which have many elements. */
1495 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1498 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1500 field = TYPE_FIELDS (type);
1502 top = TYPE_LANG_SPECIFIC (type)->s->len;
1503 while (top - bot > 1)
1505 half = (top - bot + 1) >> 1;
1506 field = field_array[bot+half];
1508 if (DECL_NAME (field) == NULL_TREE)
1510 /* Step through all anon unions in linear fashion. */
1511 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1513 field = field_array[bot++];
1514 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1515 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1517 tree anon = lookup_field (field, component);
1520 return tree_cons (NULL_TREE, field, anon);
1524 /* Entire record is only anon unions. */
1528 /* Restart the binary search, with new lower bound. */
1532 if (DECL_NAME (field) == component)
1534 if (DECL_NAME (field) < component)
1540 if (DECL_NAME (field_array[bot]) == component)
1541 field = field_array[bot];
1542 else if (DECL_NAME (field) != component)
1547 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1549 if (DECL_NAME (field) == NULL_TREE
1550 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1551 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1553 tree anon = lookup_field (field, component);
1556 return tree_cons (NULL_TREE, field, anon);
1559 if (DECL_NAME (field) == component)
1563 if (field == NULL_TREE)
1567 return tree_cons (NULL_TREE, field, NULL_TREE);
1570 /* Make an expression to refer to the COMPONENT field of
1571 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1574 build_component_ref (tree datum, tree component)
1576 tree type = TREE_TYPE (datum);
1577 enum tree_code code = TREE_CODE (type);
1581 if (!objc_is_public (datum, component))
1582 return error_mark_node;
1584 /* See if there is a field or component with name COMPONENT. */
1586 if (code == RECORD_TYPE || code == UNION_TYPE)
1588 if (!COMPLETE_TYPE_P (type))
1590 c_incomplete_type_error (NULL_TREE, type);
1591 return error_mark_node;
1594 field = lookup_field (datum, component);
1598 error ("%qT has no member named %qE", type, component);
1599 return error_mark_node;
1602 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1603 This might be better solved in future the way the C++ front
1604 end does it - by giving the anonymous entities each a
1605 separate name and type, and then have build_component_ref
1606 recursively call itself. We can't do that here. */
1609 tree subdatum = TREE_VALUE (field);
1611 if (TREE_TYPE (subdatum) == error_mark_node)
1612 return error_mark_node;
1614 ref = build3 (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum,
1616 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1617 TREE_READONLY (ref) = 1;
1618 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1619 TREE_THIS_VOLATILE (ref) = 1;
1621 if (TREE_DEPRECATED (subdatum))
1622 warn_deprecated_use (subdatum);
1626 field = TREE_CHAIN (field);
1632 else if (code != ERROR_MARK)
1633 error ("request for member %qE in something not a structure or union",
1636 return error_mark_node;
1639 /* Given an expression PTR for a pointer, return an expression
1640 for the value pointed to.
1641 ERRORSTRING is the name of the operator to appear in error messages. */
1644 build_indirect_ref (tree ptr, const char *errorstring)
1646 tree pointer = default_conversion (ptr);
1647 tree type = TREE_TYPE (pointer);
1649 if (TREE_CODE (type) == POINTER_TYPE)
1651 if (TREE_CODE (pointer) == ADDR_EXPR
1652 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1653 == TREE_TYPE (type)))
1654 return TREE_OPERAND (pointer, 0);
1657 tree t = TREE_TYPE (type);
1661 if (TREE_CODE (mvt) != ARRAY_TYPE)
1662 mvt = TYPE_MAIN_VARIANT (mvt);
1663 ref = build1 (INDIRECT_REF, mvt, pointer);
1665 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1667 error ("dereferencing pointer to incomplete type");
1668 return error_mark_node;
1670 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1671 warning (0, "dereferencing %<void *%> pointer");
1673 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1674 so that we get the proper error message if the result is used
1675 to assign to. Also, &* is supposed to be a no-op.
1676 And ANSI C seems to specify that the type of the result
1677 should be the const type. */
1678 /* A de-reference of a pointer to const is not a const. It is valid
1679 to change it via some other pointer. */
1680 TREE_READONLY (ref) = TYPE_READONLY (t);
1681 TREE_SIDE_EFFECTS (ref)
1682 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1683 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1687 else if (TREE_CODE (pointer) != ERROR_MARK)
1688 error ("invalid type argument of %qs", errorstring);
1689 return error_mark_node;
1692 /* This handles expressions of the form "a[i]", which denotes
1695 This is logically equivalent in C to *(a+i), but we may do it differently.
1696 If A is a variable or a member, we generate a primitive ARRAY_REF.
1697 This avoids forcing the array out of registers, and can work on
1698 arrays that are not lvalues (for example, members of structures returned
1702 build_array_ref (tree array, tree index)
1704 bool swapped = false;
1705 if (TREE_TYPE (array) == error_mark_node
1706 || TREE_TYPE (index) == error_mark_node)
1707 return error_mark_node;
1709 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1710 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1713 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1714 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1716 error ("subscripted value is neither array nor pointer");
1717 return error_mark_node;
1725 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1727 error ("array subscript is not an integer");
1728 return error_mark_node;
1731 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1733 error ("subscripted value is pointer to function");
1734 return error_mark_node;
1737 /* Subscripting with type char is likely to lose on a machine where
1738 chars are signed. So warn on any machine, but optionally. Don't
1739 warn for unsigned char since that type is safe. Don't warn for
1740 signed char because anyone who uses that must have done so
1741 deliberately. ??? Existing practice has also been to warn only
1742 when the char index is syntactically the index, not for
1744 if (warn_char_subscripts && !swapped
1745 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1746 warning (0, "array subscript has type %<char%>");
1748 /* Apply default promotions *after* noticing character types. */
1749 index = default_conversion (index);
1751 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1753 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1757 /* An array that is indexed by a non-constant
1758 cannot be stored in a register; we must be able to do
1759 address arithmetic on its address.
1760 Likewise an array of elements of variable size. */
1761 if (TREE_CODE (index) != INTEGER_CST
1762 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1763 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1765 if (!c_mark_addressable (array))
1766 return error_mark_node;
1768 /* An array that is indexed by a constant value which is not within
1769 the array bounds cannot be stored in a register either; because we
1770 would get a crash in store_bit_field/extract_bit_field when trying
1771 to access a non-existent part of the register. */
1772 if (TREE_CODE (index) == INTEGER_CST
1773 && TYPE_DOMAIN (TREE_TYPE (array))
1774 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1776 if (!c_mark_addressable (array))
1777 return error_mark_node;
1783 while (TREE_CODE (foo) == COMPONENT_REF)
1784 foo = TREE_OPERAND (foo, 0);
1785 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1786 pedwarn ("ISO C forbids subscripting %<register%> array");
1787 else if (!flag_isoc99 && !lvalue_p (foo))
1788 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1791 type = TREE_TYPE (TREE_TYPE (array));
1792 if (TREE_CODE (type) != ARRAY_TYPE)
1793 type = TYPE_MAIN_VARIANT (type);
1794 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
1795 /* Array ref is const/volatile if the array elements are
1796 or if the array is. */
1797 TREE_READONLY (rval)
1798 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1799 | TREE_READONLY (array));
1800 TREE_SIDE_EFFECTS (rval)
1801 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1802 | TREE_SIDE_EFFECTS (array));
1803 TREE_THIS_VOLATILE (rval)
1804 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1805 /* This was added by rms on 16 Nov 91.
1806 It fixes vol struct foo *a; a->elts[1]
1807 in an inline function.
1808 Hope it doesn't break something else. */
1809 | TREE_THIS_VOLATILE (array));
1810 return require_complete_type (fold (rval));
1814 tree ar = default_conversion (array);
1816 if (ar == error_mark_node)
1819 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
1820 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
1822 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
1827 /* Build an external reference to identifier ID. FUN indicates
1828 whether this will be used for a function call. LOC is the source
1829 location of the identifier. */
1831 build_external_ref (tree id, int fun, location_t loc)
1834 tree decl = lookup_name (id);
1836 /* In Objective-C, an instance variable (ivar) may be preferred to
1837 whatever lookup_name() found. */
1838 decl = objc_lookup_ivar (decl, id);
1840 if (decl && decl != error_mark_node)
1843 /* Implicit function declaration. */
1844 ref = implicitly_declare (id);
1845 else if (decl == error_mark_node)
1846 /* Don't complain about something that's already been
1847 complained about. */
1848 return error_mark_node;
1851 undeclared_variable (id, loc);
1852 return error_mark_node;
1855 if (TREE_TYPE (ref) == error_mark_node)
1856 return error_mark_node;
1858 if (TREE_DEPRECATED (ref))
1859 warn_deprecated_use (ref);
1861 if (!skip_evaluation)
1862 assemble_external (ref);
1863 TREE_USED (ref) = 1;
1865 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
1867 if (!in_sizeof && !in_typeof)
1868 C_DECL_USED (ref) = 1;
1869 else if (DECL_INITIAL (ref) == 0
1870 && DECL_EXTERNAL (ref)
1871 && !TREE_PUBLIC (ref))
1872 record_maybe_used_decl (ref);
1875 if (TREE_CODE (ref) == CONST_DECL)
1877 ref = DECL_INITIAL (ref);
1878 TREE_CONSTANT (ref) = 1;
1879 TREE_INVARIANT (ref) = 1;
1881 else if (current_function_decl != 0
1882 && !DECL_FILE_SCOPE_P (current_function_decl)
1883 && (TREE_CODE (ref) == VAR_DECL
1884 || TREE_CODE (ref) == PARM_DECL
1885 || TREE_CODE (ref) == FUNCTION_DECL))
1887 tree context = decl_function_context (ref);
1889 if (context != 0 && context != current_function_decl)
1890 DECL_NONLOCAL (ref) = 1;
1896 /* Record details of decls possibly used inside sizeof or typeof. */
1897 struct maybe_used_decl
1901 /* The level seen at (in_sizeof + in_typeof). */
1903 /* The next one at this level or above, or NULL. */
1904 struct maybe_used_decl *next;
1907 static struct maybe_used_decl *maybe_used_decls;
1909 /* Record that DECL, an undefined static function reference seen
1910 inside sizeof or typeof, might be used if the operand of sizeof is
1911 a VLA type or the operand of typeof is a variably modified
1915 record_maybe_used_decl (tree decl)
1917 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
1919 t->level = in_sizeof + in_typeof;
1920 t->next = maybe_used_decls;
1921 maybe_used_decls = t;
1924 /* Pop the stack of decls possibly used inside sizeof or typeof. If
1925 USED is false, just discard them. If it is true, mark them used
1926 (if no longer inside sizeof or typeof) or move them to the next
1927 level up (if still inside sizeof or typeof). */
1930 pop_maybe_used (bool used)
1932 struct maybe_used_decl *p = maybe_used_decls;
1933 int cur_level = in_sizeof + in_typeof;
1934 while (p && p->level > cur_level)
1939 C_DECL_USED (p->decl) = 1;
1941 p->level = cur_level;
1945 if (!used || cur_level == 0)
1946 maybe_used_decls = p;
1949 /* Return the result of sizeof applied to EXPR. */
1952 c_expr_sizeof_expr (struct c_expr expr)
1955 if (expr.value == error_mark_node)
1957 ret.value = error_mark_node;
1958 ret.original_code = ERROR_MARK;
1959 pop_maybe_used (false);
1963 ret.value = c_sizeof (TREE_TYPE (expr.value));
1964 ret.original_code = ERROR_MARK;
1965 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
1970 /* Return the result of sizeof applied to T, a structure for the type
1971 name passed to sizeof (rather than the type itself). */
1974 c_expr_sizeof_type (struct c_type_name *t)
1978 type = groktypename (t);
1979 ret.value = c_sizeof (type);
1980 ret.original_code = ERROR_MARK;
1981 pop_maybe_used (C_TYPE_VARIABLE_SIZE (type));
1985 /* Build a function call to function FUNCTION with parameters PARAMS.
1986 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1987 TREE_VALUE of each node is a parameter-expression.
1988 FUNCTION's data type may be a function type or a pointer-to-function. */
1991 build_function_call (tree function, tree params)
1993 tree fntype, fundecl = 0;
1994 tree coerced_params;
1995 tree name = NULL_TREE, result;
1998 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1999 STRIP_TYPE_NOPS (function);
2001 /* Convert anything with function type to a pointer-to-function. */
2002 if (TREE_CODE (function) == FUNCTION_DECL)
2004 /* Implement type-directed function overloading for builtins.
2005 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2006 handle all the type checking. The result is a complete expression
2007 that implements this function call. */
2008 tem = resolve_overloaded_builtin (function, params);
2012 name = DECL_NAME (function);
2014 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2015 (because calling an inline function does not mean the function
2016 needs to be separately compiled). */
2017 fntype = build_type_variant (TREE_TYPE (function),
2018 TREE_READONLY (function),
2019 TREE_THIS_VOLATILE (function));
2021 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
2024 function = default_conversion (function);
2026 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2027 expressions, like those used for ObjC messenger dispatches. */
2028 function = objc_rewrite_function_call (function, params);
2030 fntype = TREE_TYPE (function);
2032 if (TREE_CODE (fntype) == ERROR_MARK)
2033 return error_mark_node;
2035 if (!(TREE_CODE (fntype) == POINTER_TYPE
2036 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2038 error ("called object %qE is not a function", function);
2039 return error_mark_node;
2042 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2043 current_function_returns_abnormally = 1;
2045 /* fntype now gets the type of function pointed to. */
2046 fntype = TREE_TYPE (fntype);
2048 /* Check that the function is called through a compatible prototype.
2049 If it is not, replace the call by a trap, wrapped up in a compound
2050 expression if necessary. This has the nice side-effect to prevent
2051 the tree-inliner from generating invalid assignment trees which may
2052 blow up in the RTL expander later.
2054 ??? This doesn't work for Objective-C because objc_comptypes
2055 refuses to compare function prototypes, yet the compiler appears
2056 to build calls that are flagged as invalid by C's comptypes. */
2057 if (!c_dialect_objc ()
2058 && TREE_CODE (function) == NOP_EXPR
2059 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2060 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2061 && !comptypes (fntype, TREE_TYPE (tem)))
2063 tree return_type = TREE_TYPE (fntype);
2064 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2067 /* This situation leads to run-time undefined behavior. We can't,
2068 therefore, simply error unless we can prove that all possible
2069 executions of the program must execute the code. */
2070 warning (0, "function called through a non-compatible type");
2072 /* We can, however, treat "undefined" any way we please.
2073 Call abort to encourage the user to fix the program. */
2074 inform ("if this code is reached, the program will abort");
2076 if (VOID_TYPE_P (return_type))
2082 if (AGGREGATE_TYPE_P (return_type))
2083 rhs = build_compound_literal (return_type,
2084 build_constructor (return_type,
2087 rhs = fold (build1 (NOP_EXPR, return_type, integer_zero_node));
2089 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2093 /* Convert the parameters to the types declared in the
2094 function prototype, or apply default promotions. */
2097 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2099 if (coerced_params == error_mark_node)
2100 return error_mark_node;
2102 /* Check that the arguments to the function are valid. */
2104 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params);
2106 result = build3 (CALL_EXPR, TREE_TYPE (fntype),
2107 function, coerced_params, NULL_TREE);
2108 TREE_SIDE_EFFECTS (result) = 1;
2110 if (require_constant_value)
2112 result = fold_initializer (result);
2114 if (TREE_CONSTANT (result)
2115 && (name == NULL_TREE
2116 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2117 pedwarn_init ("initializer element is not constant");
2120 result = fold (result);
2122 if (VOID_TYPE_P (TREE_TYPE (result)))
2124 return require_complete_type (result);
2127 /* Convert the argument expressions in the list VALUES
2128 to the types in the list TYPELIST. The result is a list of converted
2129 argument expressions, unless there are too few arguments in which
2130 case it is error_mark_node.
2132 If TYPELIST is exhausted, or when an element has NULL as its type,
2133 perform the default conversions.
2135 PARMLIST is the chain of parm decls for the function being called.
2136 It may be 0, if that info is not available.
2137 It is used only for generating error messages.
2139 FUNCTION is a tree for the called function. It is used only for
2140 error messages, where it is formatted with %qE.
2142 This is also where warnings about wrong number of args are generated.
2144 Both VALUES and the returned value are chains of TREE_LIST nodes
2145 with the elements of the list in the TREE_VALUE slots of those nodes. */
2148 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2150 tree typetail, valtail;
2155 /* Change pointer to function to the function itself for
2157 if (TREE_CODE (function) == ADDR_EXPR
2158 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2159 function = TREE_OPERAND (function, 0);
2161 /* Handle an ObjC selector specially for diagnostics. */
2162 selector = objc_message_selector ();
2164 /* Scan the given expressions and types, producing individual
2165 converted arguments and pushing them on RESULT in reverse order. */
2167 for (valtail = values, typetail = typelist, parmnum = 0;
2169 valtail = TREE_CHAIN (valtail), parmnum++)
2171 tree type = typetail ? TREE_VALUE (typetail) : 0;
2172 tree val = TREE_VALUE (valtail);
2173 tree rname = function;
2174 int argnum = parmnum + 1;
2175 const char *invalid_func_diag;
2177 if (type == void_type_node)
2179 error ("too many arguments to function %qE", function);
2183 if (selector && argnum > 2)
2189 STRIP_TYPE_NOPS (val);
2191 val = default_function_array_conversion (val);
2193 val = require_complete_type (val);
2197 /* Formal parm type is specified by a function prototype. */
2200 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2202 error ("type of formal parameter %d is incomplete", parmnum + 1);
2207 /* Optionally warn about conversions that
2208 differ from the default conversions. */
2209 if (warn_conversion || warn_traditional)
2211 unsigned int formal_prec = TYPE_PRECISION (type);
2213 if (INTEGRAL_TYPE_P (type)
2214 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2215 warning (0, "passing argument %d of %qE as integer "
2216 "rather than floating due to prototype",
2218 if (INTEGRAL_TYPE_P (type)
2219 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2220 warning (0, "passing argument %d of %qE as integer "
2221 "rather than complex due to prototype",
2223 else if (TREE_CODE (type) == COMPLEX_TYPE
2224 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2225 warning (0, "passing argument %d of %qE as complex "
2226 "rather than floating due to prototype",
2228 else if (TREE_CODE (type) == REAL_TYPE
2229 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2230 warning (0, "passing argument %d of %qE as floating "
2231 "rather than integer due to prototype",
2233 else if (TREE_CODE (type) == COMPLEX_TYPE
2234 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2235 warning (0, "passing argument %d of %qE as complex "
2236 "rather than integer due to prototype",
2238 else if (TREE_CODE (type) == REAL_TYPE
2239 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2240 warning (0, "passing argument %d of %qE as floating "
2241 "rather than complex due to prototype",
2243 /* ??? At some point, messages should be written about
2244 conversions between complex types, but that's too messy
2246 else if (TREE_CODE (type) == REAL_TYPE
2247 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2249 /* Warn if any argument is passed as `float',
2250 since without a prototype it would be `double'. */
2251 if (formal_prec == TYPE_PRECISION (float_type_node))
2252 warning (0, "passing argument %d of %qE as %<float%> "
2253 "rather than %<double%> due to prototype",
2256 /* Detect integer changing in width or signedness.
2257 These warnings are only activated with
2258 -Wconversion, not with -Wtraditional. */
2259 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2260 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2262 tree would_have_been = default_conversion (val);
2263 tree type1 = TREE_TYPE (would_have_been);
2265 if (TREE_CODE (type) == ENUMERAL_TYPE
2266 && (TYPE_MAIN_VARIANT (type)
2267 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2268 /* No warning if function asks for enum
2269 and the actual arg is that enum type. */
2271 else if (formal_prec != TYPE_PRECISION (type1))
2272 warning (0, "passing argument %d of %qE with different "
2273 "width due to prototype", argnum, rname);
2274 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2276 /* Don't complain if the formal parameter type
2277 is an enum, because we can't tell now whether
2278 the value was an enum--even the same enum. */
2279 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2281 else if (TREE_CODE (val) == INTEGER_CST
2282 && int_fits_type_p (val, type))
2283 /* Change in signedness doesn't matter
2284 if a constant value is unaffected. */
2286 /* If the value is extended from a narrower
2287 unsigned type, it doesn't matter whether we
2288 pass it as signed or unsigned; the value
2289 certainly is the same either way. */
2290 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2291 && TYPE_UNSIGNED (TREE_TYPE (val)))
2293 else if (TYPE_UNSIGNED (type))
2294 warning (0, "passing argument %d of %qE as unsigned "
2295 "due to prototype", argnum, rname);
2297 warning (0, "passing argument %d of %qE as signed "
2298 "due to prototype", argnum, rname);
2302 parmval = convert_for_assignment (type, val, ic_argpass,
2306 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2307 && INTEGRAL_TYPE_P (type)
2308 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2309 parmval = default_conversion (parmval);
2311 result = tree_cons (NULL_TREE, parmval, result);
2313 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2314 && (TYPE_PRECISION (TREE_TYPE (val))
2315 < TYPE_PRECISION (double_type_node)))
2316 /* Convert `float' to `double'. */
2317 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2318 else if ((invalid_func_diag =
2319 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2321 error (invalid_func_diag);
2322 return error_mark_node;
2325 /* Convert `short' and `char' to full-size `int'. */
2326 result = tree_cons (NULL_TREE, default_conversion (val), result);
2329 typetail = TREE_CHAIN (typetail);
2332 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2334 error ("too few arguments to function %qE", function);
2335 return error_mark_node;
2338 return nreverse (result);
2341 /* This is the entry point used by the parser to build unary operators
2342 in the input. CODE, a tree_code, specifies the unary operator, and
2343 ARG is the operand. For unary plus, the C parser currently uses
2344 CONVERT_EXPR for code. */
2347 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2349 struct c_expr result;
2351 result.original_code = ERROR_MARK;
2352 result.value = build_unary_op (code, arg.value, 0);
2353 overflow_warning (result.value);
2357 /* This is the entry point used by the parser to build binary operators
2358 in the input. CODE, a tree_code, specifies the binary operator, and
2359 ARG1 and ARG2 are the operands. In addition to constructing the
2360 expression, we check for operands that were written with other binary
2361 operators in a way that is likely to confuse the user. */
2364 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2367 struct c_expr result;
2369 enum tree_code code1 = arg1.original_code;
2370 enum tree_code code2 = arg2.original_code;
2372 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2373 result.original_code = code;
2375 if (TREE_CODE (result.value) == ERROR_MARK)
2378 /* Check for cases such as x+y<<z which users are likely
2380 if (warn_parentheses)
2382 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2384 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2385 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2386 warning (0, "suggest parentheses around + or - inside shift");
2389 if (code == TRUTH_ORIF_EXPR)
2391 if (code1 == TRUTH_ANDIF_EXPR
2392 || code2 == TRUTH_ANDIF_EXPR)
2393 warning (0, "suggest parentheses around && within ||");
2396 if (code == BIT_IOR_EXPR)
2398 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2399 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2400 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2401 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2402 warning (0, "suggest parentheses around arithmetic in operand of |");
2403 /* Check cases like x|y==z */
2404 if (TREE_CODE_CLASS (code1) == tcc_comparison
2405 || TREE_CODE_CLASS (code2) == tcc_comparison)
2406 warning (0, "suggest parentheses around comparison in operand of |");
2409 if (code == BIT_XOR_EXPR)
2411 if (code1 == BIT_AND_EXPR
2412 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2413 || code2 == BIT_AND_EXPR
2414 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2415 warning (0, "suggest parentheses around arithmetic in operand of ^");
2416 /* Check cases like x^y==z */
2417 if (TREE_CODE_CLASS (code1) == tcc_comparison
2418 || TREE_CODE_CLASS (code2) == tcc_comparison)
2419 warning (0, "suggest parentheses around comparison in operand of ^");
2422 if (code == BIT_AND_EXPR)
2424 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2425 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2426 warning (0, "suggest parentheses around + or - in operand of &");
2427 /* Check cases like x&y==z */
2428 if (TREE_CODE_CLASS (code1) == tcc_comparison
2429 || TREE_CODE_CLASS (code2) == tcc_comparison)
2430 warning (0, "suggest parentheses around comparison in operand of &");
2432 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2433 if (TREE_CODE_CLASS (code) == tcc_comparison
2434 && (TREE_CODE_CLASS (code1) == tcc_comparison
2435 || TREE_CODE_CLASS (code2) == tcc_comparison))
2436 warning (0, "comparisons like X<=Y<=Z do not have their mathematical meaning");
2440 unsigned_conversion_warning (result.value, arg1.value);
2441 unsigned_conversion_warning (result.value, arg2.value);
2442 overflow_warning (result.value);
2447 /* Return a tree for the difference of pointers OP0 and OP1.
2448 The resulting tree has type int. */
2451 pointer_diff (tree op0, tree op1)
2453 tree restype = ptrdiff_type_node;
2455 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2456 tree con0, con1, lit0, lit1;
2457 tree orig_op1 = op1;
2459 if (pedantic || warn_pointer_arith)
2461 if (TREE_CODE (target_type) == VOID_TYPE)
2462 pedwarn ("pointer of type %<void *%> used in subtraction");
2463 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2464 pedwarn ("pointer to a function used in subtraction");
2467 /* If the conversion to ptrdiff_type does anything like widening or
2468 converting a partial to an integral mode, we get a convert_expression
2469 that is in the way to do any simplifications.
2470 (fold-const.c doesn't know that the extra bits won't be needed.
2471 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2472 different mode in place.)
2473 So first try to find a common term here 'by hand'; we want to cover
2474 at least the cases that occur in legal static initializers. */
2475 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2476 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2478 if (TREE_CODE (con0) == PLUS_EXPR)
2480 lit0 = TREE_OPERAND (con0, 1);
2481 con0 = TREE_OPERAND (con0, 0);
2484 lit0 = integer_zero_node;
2486 if (TREE_CODE (con1) == PLUS_EXPR)
2488 lit1 = TREE_OPERAND (con1, 1);
2489 con1 = TREE_OPERAND (con1, 0);
2492 lit1 = integer_zero_node;
2494 if (operand_equal_p (con0, con1, 0))
2501 /* First do the subtraction as integers;
2502 then drop through to build the divide operator.
2503 Do not do default conversions on the minus operator
2504 in case restype is a short type. */
2506 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2507 convert (restype, op1), 0);
2508 /* This generates an error if op1 is pointer to incomplete type. */
2509 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2510 error ("arithmetic on pointer to an incomplete type");
2512 /* This generates an error if op0 is pointer to incomplete type. */
2513 op1 = c_size_in_bytes (target_type);
2515 /* Divide by the size, in easiest possible way. */
2516 return fold (build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)));
2519 /* Construct and perhaps optimize a tree representation
2520 for a unary operation. CODE, a tree_code, specifies the operation
2521 and XARG is the operand.
2522 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2523 the default promotions (such as from short to int).
2524 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2525 allows non-lvalues; this is only used to handle conversion of non-lvalue
2526 arrays to pointers in C99. */
2529 build_unary_op (enum tree_code code, tree xarg, int flag)
2531 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2534 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2536 int noconvert = flag;
2538 if (typecode == ERROR_MARK)
2539 return error_mark_node;
2540 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2541 typecode = INTEGER_TYPE;
2546 /* This is used for unary plus, because a CONVERT_EXPR
2547 is enough to prevent anybody from looking inside for
2548 associativity, but won't generate any code. */
2549 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2550 || typecode == COMPLEX_TYPE
2551 || typecode == VECTOR_TYPE))
2553 error ("wrong type argument to unary plus");
2554 return error_mark_node;
2556 else if (!noconvert)
2557 arg = default_conversion (arg);
2558 arg = non_lvalue (arg);
2562 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2563 || typecode == COMPLEX_TYPE
2564 || typecode == VECTOR_TYPE))
2566 error ("wrong type argument to unary minus");
2567 return error_mark_node;
2569 else if (!noconvert)
2570 arg = default_conversion (arg);
2574 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2577 arg = default_conversion (arg);
2579 else if (typecode == COMPLEX_TYPE)
2583 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2585 arg = default_conversion (arg);
2589 error ("wrong type argument to bit-complement");
2590 return error_mark_node;
2595 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2597 error ("wrong type argument to abs");
2598 return error_mark_node;
2600 else if (!noconvert)
2601 arg = default_conversion (arg);
2605 /* Conjugating a real value is a no-op, but allow it anyway. */
2606 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2607 || typecode == COMPLEX_TYPE))
2609 error ("wrong type argument to conjugation");
2610 return error_mark_node;
2612 else if (!noconvert)
2613 arg = default_conversion (arg);
2616 case TRUTH_NOT_EXPR:
2617 /* ??? Why do most validation here but that for non-lvalue arrays
2618 in c_objc_common_truthvalue_conversion? */
2619 if (typecode != INTEGER_TYPE
2620 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2621 && typecode != COMPLEX_TYPE
2622 /* These will convert to a pointer. */
2623 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2625 error ("wrong type argument to unary exclamation mark");
2626 return error_mark_node;
2628 arg = c_objc_common_truthvalue_conversion (arg);
2629 return invert_truthvalue (arg);
2635 if (TREE_CODE (arg) == COMPLEX_CST)
2636 return TREE_REALPART (arg);
2637 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2638 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2643 if (TREE_CODE (arg) == COMPLEX_CST)
2644 return TREE_IMAGPART (arg);
2645 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2646 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2648 return convert (TREE_TYPE (arg), integer_zero_node);
2650 case PREINCREMENT_EXPR:
2651 case POSTINCREMENT_EXPR:
2652 case PREDECREMENT_EXPR:
2653 case POSTDECREMENT_EXPR:
2655 /* Increment or decrement the real part of the value,
2656 and don't change the imaginary part. */
2657 if (typecode == COMPLEX_TYPE)
2662 pedwarn ("ISO C does not support %<++%> and %<--%>"
2663 " on complex types");
2665 arg = stabilize_reference (arg);
2666 real = build_unary_op (REALPART_EXPR, arg, 1);
2667 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2668 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2669 build_unary_op (code, real, 1), imag);
2672 /* Report invalid types. */
2674 if (typecode != POINTER_TYPE
2675 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2677 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2678 error ("wrong type argument to increment");
2680 error ("wrong type argument to decrement");
2682 return error_mark_node;
2687 tree result_type = TREE_TYPE (arg);
2689 arg = get_unwidened (arg, 0);
2690 argtype = TREE_TYPE (arg);
2692 /* Compute the increment. */
2694 if (typecode == POINTER_TYPE)
2696 /* If pointer target is an undefined struct,
2697 we just cannot know how to do the arithmetic. */
2698 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2700 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2701 error ("increment of pointer to unknown structure");
2703 error ("decrement of pointer to unknown structure");
2705 else if ((pedantic || warn_pointer_arith)
2706 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2707 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2709 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2710 pedwarn ("wrong type argument to increment");
2712 pedwarn ("wrong type argument to decrement");
2715 inc = c_size_in_bytes (TREE_TYPE (result_type));
2718 inc = integer_one_node;
2720 inc = convert (argtype, inc);
2722 /* Complain about anything else that is not a true lvalue. */
2723 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2724 || code == POSTINCREMENT_EXPR)
2727 return error_mark_node;
2729 /* Report a read-only lvalue. */
2730 if (TREE_READONLY (arg))
2731 readonly_error (arg,
2732 ((code == PREINCREMENT_EXPR
2733 || code == POSTINCREMENT_EXPR)
2734 ? lv_increment : lv_decrement));
2736 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2737 val = boolean_increment (code, arg);
2739 val = build2 (code, TREE_TYPE (arg), arg, inc);
2740 TREE_SIDE_EFFECTS (val) = 1;
2741 val = convert (result_type, val);
2742 if (TREE_CODE (val) != code)
2743 TREE_NO_WARNING (val) = 1;
2748 /* Note that this operation never does default_conversion. */
2750 /* Let &* cancel out to simplify resulting code. */
2751 if (TREE_CODE (arg) == INDIRECT_REF)
2753 /* Don't let this be an lvalue. */
2754 if (lvalue_p (TREE_OPERAND (arg, 0)))
2755 return non_lvalue (TREE_OPERAND (arg, 0));
2756 return TREE_OPERAND (arg, 0);
2759 /* For &x[y], return x+y */
2760 if (TREE_CODE (arg) == ARRAY_REF)
2762 if (!c_mark_addressable (TREE_OPERAND (arg, 0)))
2763 return error_mark_node;
2764 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2765 TREE_OPERAND (arg, 1), 1);
2768 /* Anything not already handled and not a true memory reference
2769 or a non-lvalue array is an error. */
2770 else if (typecode != FUNCTION_TYPE && !flag
2771 && !lvalue_or_else (arg, lv_addressof))
2772 return error_mark_node;
2774 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2775 argtype = TREE_TYPE (arg);
2777 /* If the lvalue is const or volatile, merge that into the type
2778 to which the address will point. Note that you can't get a
2779 restricted pointer by taking the address of something, so we
2780 only have to deal with `const' and `volatile' here. */
2781 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
2782 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2783 argtype = c_build_type_variant (argtype,
2784 TREE_READONLY (arg),
2785 TREE_THIS_VOLATILE (arg));
2787 if (!c_mark_addressable (arg))
2788 return error_mark_node;
2790 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
2791 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
2793 argtype = build_pointer_type (argtype);
2795 /* ??? Cope with user tricks that amount to offsetof. Delete this
2796 when we have proper support for integer constant expressions. */
2797 val = get_base_address (arg);
2798 if (val && TREE_CODE (val) == INDIRECT_REF
2799 && integer_zerop (TREE_OPERAND (val, 0)))
2800 return fold_convert (argtype, fold_offsetof (arg));
2802 val = build1 (ADDR_EXPR, argtype, arg);
2804 if (TREE_CODE (arg) == COMPOUND_LITERAL_EXPR)
2805 TREE_INVARIANT (val) = TREE_CONSTANT (val) = 1;
2814 argtype = TREE_TYPE (arg);
2815 val = build1 (code, argtype, arg);
2816 return require_constant_value ? fold_initializer (val) : fold (val);
2819 /* Return nonzero if REF is an lvalue valid for this language.
2820 Lvalues can be assigned, unless their type has TYPE_READONLY.
2821 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2826 enum tree_code code = TREE_CODE (ref);
2833 return lvalue_p (TREE_OPERAND (ref, 0));
2835 case COMPOUND_LITERAL_EXPR:
2845 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2846 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2849 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2856 /* Give an error for storing in something that is 'const'. */
2859 readonly_error (tree arg, enum lvalue_use use)
2861 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2862 /* Using this macro rather than (for example) arrays of messages
2863 ensures that all the format strings are checked at compile
2865 #define READONLY_MSG(A, I, D) (use == lv_assign \
2867 : (use == lv_increment ? (I) : (D)))
2868 if (TREE_CODE (arg) == COMPONENT_REF)
2870 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2871 readonly_error (TREE_OPERAND (arg, 0), use);
2873 error (READONLY_MSG (N_("assignment of read-only member %qD"),
2874 N_("increment of read-only member %qD"),
2875 N_("decrement of read-only member %qD")),
2876 TREE_OPERAND (arg, 1));
2878 else if (TREE_CODE (arg) == VAR_DECL)
2879 error (READONLY_MSG (N_("assignment of read-only variable %qD"),
2880 N_("increment of read-only variable %qD"),
2881 N_("decrement of read-only variable %qD")),
2884 error (READONLY_MSG (N_("assignment of read-only location"),
2885 N_("increment of read-only location"),
2886 N_("decrement of read-only location")));
2890 /* Return nonzero if REF is an lvalue valid for this language;
2891 otherwise, print an error message and return zero. USE says
2892 how the lvalue is being used and so selects the error message. */
2895 lvalue_or_else (tree ref, enum lvalue_use use)
2897 int win = lvalue_p (ref);
2905 /* Mark EXP saying that we need to be able to take the
2906 address of it; it should not be allocated in a register.
2907 Returns true if successful. */
2910 c_mark_addressable (tree exp)
2915 switch (TREE_CODE (x))
2918 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2921 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2925 /* ... fall through ... */
2931 x = TREE_OPERAND (x, 0);
2934 case COMPOUND_LITERAL_EXPR:
2936 TREE_ADDRESSABLE (x) = 1;
2943 if (C_DECL_REGISTER (x)
2944 && DECL_NONLOCAL (x))
2946 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2949 ("global register variable %qD used in nested function", x);
2952 pedwarn ("register variable %qD used in nested function", x);
2954 else if (C_DECL_REGISTER (x))
2956 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2957 error ("address of global register variable %qD requested", x);
2959 error ("address of register variable %qD requested", x);
2965 TREE_ADDRESSABLE (x) = 1;
2972 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2975 build_conditional_expr (tree ifexp, tree op1, tree op2)
2979 enum tree_code code1;
2980 enum tree_code code2;
2981 tree result_type = NULL;
2982 tree orig_op1 = op1, orig_op2 = op2;
2984 /* Promote both alternatives. */
2986 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2987 op1 = default_conversion (op1);
2988 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2989 op2 = default_conversion (op2);
2991 if (TREE_CODE (ifexp) == ERROR_MARK
2992 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2993 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2994 return error_mark_node;
2996 type1 = TREE_TYPE (op1);
2997 code1 = TREE_CODE (type1);
2998 type2 = TREE_TYPE (op2);
2999 code2 = TREE_CODE (type2);
3001 /* C90 does not permit non-lvalue arrays in conditional expressions.
3002 In C99 they will be pointers by now. */
3003 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3005 error ("non-lvalue array in conditional expression");
3006 return error_mark_node;
3009 /* Quickly detect the usual case where op1 and op2 have the same type
3011 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3014 result_type = type1;
3016 result_type = TYPE_MAIN_VARIANT (type1);
3018 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3019 || code1 == COMPLEX_TYPE)
3020 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3021 || code2 == COMPLEX_TYPE))
3023 result_type = c_common_type (type1, type2);
3025 /* If -Wsign-compare, warn here if type1 and type2 have
3026 different signedness. We'll promote the signed to unsigned
3027 and later code won't know it used to be different.
3028 Do this check on the original types, so that explicit casts
3029 will be considered, but default promotions won't. */
3030 if (warn_sign_compare && !skip_evaluation)
3032 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3033 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3035 if (unsigned_op1 ^ unsigned_op2)
3037 /* Do not warn if the result type is signed, since the
3038 signed type will only be chosen if it can represent
3039 all the values of the unsigned type. */
3040 if (!TYPE_UNSIGNED (result_type))
3042 /* Do not warn if the signed quantity is an unsuffixed
3043 integer literal (or some static constant expression
3044 involving such literals) and it is non-negative. */
3045 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3046 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3049 warning (0, "signed and unsigned type in conditional expression");
3053 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3055 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3056 pedwarn ("ISO C forbids conditional expr with only one void side");
3057 result_type = void_type_node;
3059 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3061 if (comp_target_types (type1, type2, 1))
3062 result_type = common_pointer_type (type1, type2);
3063 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3064 && TREE_CODE (orig_op1) != NOP_EXPR)
3065 result_type = qualify_type (type2, type1);
3066 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3067 && TREE_CODE (orig_op2) != NOP_EXPR)
3068 result_type = qualify_type (type1, type2);
3069 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3071 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3072 pedwarn ("ISO C forbids conditional expr between "
3073 "%<void *%> and function pointer");
3074 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3075 TREE_TYPE (type2)));
3077 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3079 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3080 pedwarn ("ISO C forbids conditional expr between "
3081 "%<void *%> and function pointer");
3082 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3083 TREE_TYPE (type1)));
3087 pedwarn ("pointer type mismatch in conditional expression");
3088 result_type = build_pointer_type (void_type_node);
3091 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3093 if (!integer_zerop (op2))
3094 pedwarn ("pointer/integer type mismatch in conditional expression");
3097 op2 = null_pointer_node;
3099 result_type = type1;
3101 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3103 if (!integer_zerop (op1))
3104 pedwarn ("pointer/integer type mismatch in conditional expression");
3107 op1 = null_pointer_node;
3109 result_type = type2;
3114 if (flag_cond_mismatch)
3115 result_type = void_type_node;
3118 error ("type mismatch in conditional expression");
3119 return error_mark_node;
3123 /* Merge const and volatile flags of the incoming types. */
3125 = build_type_variant (result_type,
3126 TREE_READONLY (op1) || TREE_READONLY (op2),
3127 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3129 if (result_type != TREE_TYPE (op1))
3130 op1 = convert_and_check (result_type, op1);
3131 if (result_type != TREE_TYPE (op2))
3132 op2 = convert_and_check (result_type, op2);
3134 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3137 /* Return a compound expression that performs two expressions and
3138 returns the value of the second of them. */
3141 build_compound_expr (tree expr1, tree expr2)
3143 /* Convert arrays and functions to pointers. */
3144 expr2 = default_function_array_conversion (expr2);
3146 if (!TREE_SIDE_EFFECTS (expr1))
3148 /* The left-hand operand of a comma expression is like an expression
3149 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3150 any side-effects, unless it was explicitly cast to (void). */
3151 if (warn_unused_value)
3153 if (VOID_TYPE_P (TREE_TYPE (expr1))
3154 && TREE_CODE (expr1) == CONVERT_EXPR)
3156 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3157 && TREE_CODE (expr1) == COMPOUND_EXPR
3158 && TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR)
3159 ; /* (void) a, (void) b, c */
3161 warning (0, "left-hand operand of comma expression has no effect");
3165 /* With -Wunused, we should also warn if the left-hand operand does have
3166 side-effects, but computes a value which is not used. For example, in
3167 `foo() + bar(), baz()' the result of the `+' operator is not used,
3168 so we should issue a warning. */
3169 else if (warn_unused_value)
3170 warn_if_unused_value (expr1, input_location);
3172 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3175 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3178 build_c_cast (tree type, tree expr)
3182 if (type == error_mark_node || expr == error_mark_node)
3183 return error_mark_node;
3185 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3186 only in <protocol> qualifications. But when constructing cast expressions,
3187 the protocols do matter and must be kept around. */
3188 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3189 return build1 (NOP_EXPR, type, expr);
3191 type = TYPE_MAIN_VARIANT (type);
3193 if (TREE_CODE (type) == ARRAY_TYPE)
3195 error ("cast specifies array type");
3196 return error_mark_node;
3199 if (TREE_CODE (type) == FUNCTION_TYPE)
3201 error ("cast specifies function type");
3202 return error_mark_node;
3205 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3209 if (TREE_CODE (type) == RECORD_TYPE
3210 || TREE_CODE (type) == UNION_TYPE)
3211 pedwarn ("ISO C forbids casting nonscalar to the same type");
3214 else if (TREE_CODE (type) == UNION_TYPE)
3217 value = default_function_array_conversion (value);
3219 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3220 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3221 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3229 pedwarn ("ISO C forbids casts to union type");
3230 t = digest_init (type,
3231 build_constructor (type,
3232 build_tree_list (field, value)),
3234 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3235 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3238 error ("cast to union type from type not present in union");
3239 return error_mark_node;
3245 /* If casting to void, avoid the error that would come
3246 from default_conversion in the case of a non-lvalue array. */
3247 if (type == void_type_node)
3248 return build1 (CONVERT_EXPR, type, value);
3250 /* Convert functions and arrays to pointers,
3251 but don't convert any other types. */
3252 value = default_function_array_conversion (value);
3253 otype = TREE_TYPE (value);
3255 /* Optionally warn about potentially worrisome casts. */
3258 && TREE_CODE (type) == POINTER_TYPE
3259 && TREE_CODE (otype) == POINTER_TYPE)
3261 tree in_type = type;
3262 tree in_otype = otype;
3266 /* Check that the qualifiers on IN_TYPE are a superset of
3267 the qualifiers of IN_OTYPE. The outermost level of
3268 POINTER_TYPE nodes is uninteresting and we stop as soon
3269 as we hit a non-POINTER_TYPE node on either type. */
3272 in_otype = TREE_TYPE (in_otype);
3273 in_type = TREE_TYPE (in_type);
3275 /* GNU C allows cv-qualified function types. 'const'
3276 means the function is very pure, 'volatile' means it
3277 can't return. We need to warn when such qualifiers
3278 are added, not when they're taken away. */
3279 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3280 && TREE_CODE (in_type) == FUNCTION_TYPE)
3281 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3283 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3285 while (TREE_CODE (in_type) == POINTER_TYPE
3286 && TREE_CODE (in_otype) == POINTER_TYPE);
3289 warning (0, "cast adds new qualifiers to function type");
3292 /* There are qualifiers present in IN_OTYPE that are not
3293 present in IN_TYPE. */
3294 warning (0, "cast discards qualifiers from pointer target type");
3297 /* Warn about possible alignment problems. */
3298 if (STRICT_ALIGNMENT && warn_cast_align
3299 && TREE_CODE (type) == POINTER_TYPE
3300 && TREE_CODE (otype) == POINTER_TYPE
3301 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3302 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3303 /* Don't warn about opaque types, where the actual alignment
3304 restriction is unknown. */
3305 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3306 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3307 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3308 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3309 warning (0, "cast increases required alignment of target type");
3311 if (warn_pointer_to_int_cast
3312 && TREE_CODE (type) == INTEGER_TYPE
3313 && TREE_CODE (otype) == POINTER_TYPE
3314 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3315 && !TREE_CONSTANT (value))
3316 warning (0, "cast from pointer to integer of different size");
3318 if (warn_bad_function_cast
3319 && TREE_CODE (value) == CALL_EXPR
3320 && TREE_CODE (type) != TREE_CODE (otype))
3321 warning (0, "cast from function call of type %qT to non-matching "
3322 "type %qT", otype, type);
3324 if (warn_int_to_pointer_cast
3325 && TREE_CODE (type) == POINTER_TYPE
3326 && TREE_CODE (otype) == INTEGER_TYPE
3327 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3328 /* Don't warn about converting any constant. */
3329 && !TREE_CONSTANT (value))
3330 warning (0, "cast to pointer from integer of different size");
3332 if (TREE_CODE (type) == POINTER_TYPE
3333 && TREE_CODE (otype) == POINTER_TYPE
3334 && TREE_CODE (expr) == ADDR_EXPR
3335 && DECL_P (TREE_OPERAND (expr, 0))
3336 && flag_strict_aliasing && warn_strict_aliasing
3337 && !VOID_TYPE_P (TREE_TYPE (type)))
3339 /* Casting the address of a decl to non void pointer. Warn
3340 if the cast breaks type based aliasing. */
3341 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3342 warning (0, "type-punning to incomplete type might break strict-aliasing rules");
3345 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3346 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3348 if (!alias_sets_conflict_p (set1, set2))
3349 warning (0, "dereferencing type-punned pointer will break strict-aliasing rules");
3350 else if (warn_strict_aliasing > 1
3351 && !alias_sets_might_conflict_p (set1, set2))
3352 warning (0, "dereferencing type-punned pointer might break strict-aliasing rules");
3356 /* If pedantic, warn for conversions between function and object
3357 pointer types, except for converting a null pointer constant
3358 to function pointer type. */
3360 && TREE_CODE (type) == POINTER_TYPE
3361 && TREE_CODE (otype) == POINTER_TYPE
3362 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3363 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3364 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3367 && TREE_CODE (type) == POINTER_TYPE
3368 && TREE_CODE (otype) == POINTER_TYPE
3369 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3370 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3371 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3372 && TREE_CODE (expr) != NOP_EXPR))
3373 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3376 value = convert (type, value);
3378 /* Ignore any integer overflow caused by the cast. */
3379 if (TREE_CODE (value) == INTEGER_CST)
3381 if (EXPR_P (ovalue))
3382 /* If OVALUE had overflow set, then so will VALUE, so it
3383 is safe to overwrite. */
3384 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3386 TREE_OVERFLOW (value) = 0;
3388 if (CONSTANT_CLASS_P (ovalue))
3389 /* Similarly, constant_overflow cannot have become
3391 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3395 /* Don't let a cast be an lvalue. */
3397 value = non_lvalue (value);
3402 /* Interpret a cast of expression EXPR to type TYPE. */
3404 c_cast_expr (struct c_type_name *type_name, tree expr)
3407 int saved_wsp = warn_strict_prototypes;
3409 /* This avoids warnings about unprototyped casts on
3410 integers. E.g. "#define SIG_DFL (void(*)())0". */
3411 if (TREE_CODE (expr) == INTEGER_CST)
3412 warn_strict_prototypes = 0;
3413 type = groktypename (type_name);
3414 warn_strict_prototypes = saved_wsp;
3416 return build_c_cast (type, expr);
3420 /* Build an assignment expression of lvalue LHS from value RHS.
3421 MODIFYCODE is the code for a binary operator that we use
3422 to combine the old value of LHS with RHS to get the new value.
3423 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3426 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3430 tree lhstype = TREE_TYPE (lhs);
3431 tree olhstype = lhstype;
3433 /* Types that aren't fully specified cannot be used in assignments. */
3434 lhs = require_complete_type (lhs);
3436 /* Avoid duplicate error messages from operands that had errors. */
3437 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3438 return error_mark_node;
3440 STRIP_TYPE_NOPS (rhs);
3444 /* If a binary op has been requested, combine the old LHS value with the RHS
3445 producing the value we should actually store into the LHS. */
3447 if (modifycode != NOP_EXPR)
3449 lhs = stabilize_reference (lhs);
3450 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3453 if (!lvalue_or_else (lhs, lv_assign))
3454 return error_mark_node;
3456 /* Give an error for storing in something that is 'const'. */
3458 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3459 || ((TREE_CODE (lhstype) == RECORD_TYPE
3460 || TREE_CODE (lhstype) == UNION_TYPE)
3461 && C_TYPE_FIELDS_READONLY (lhstype)))
3462 readonly_error (lhs, lv_assign);
3464 /* If storing into a structure or union member,
3465 it has probably been given type `int'.
3466 Compute the type that would go with
3467 the actual amount of storage the member occupies. */
3469 if (TREE_CODE (lhs) == COMPONENT_REF
3470 && (TREE_CODE (lhstype) == INTEGER_TYPE
3471 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3472 || TREE_CODE (lhstype) == REAL_TYPE
3473 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3474 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3476 /* If storing in a field that is in actuality a short or narrower than one,
3477 we must store in the field in its actual type. */
3479 if (lhstype != TREE_TYPE (lhs))
3481 lhs = copy_node (lhs);
3482 TREE_TYPE (lhs) = lhstype;
3485 /* Convert new value to destination type. */
3487 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3488 NULL_TREE, NULL_TREE, 0);
3489 if (TREE_CODE (newrhs) == ERROR_MARK)
3490 return error_mark_node;
3492 /* Emit ObjC write barrier, if necessary. */
3493 if (c_dialect_objc () && flag_objc_gc)
3495 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3500 /* Scan operands. */
3502 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3503 TREE_SIDE_EFFECTS (result) = 1;
3505 /* If we got the LHS in a different type for storing in,
3506 convert the result back to the nominal type of LHS
3507 so that the value we return always has the same type
3508 as the LHS argument. */
3510 if (olhstype == TREE_TYPE (result))
3512 return convert_for_assignment (olhstype, result, ic_assign,
3513 NULL_TREE, NULL_TREE, 0);
3516 /* Convert value RHS to type TYPE as preparation for an assignment
3517 to an lvalue of type TYPE.
3518 The real work of conversion is done by `convert'.
3519 The purpose of this function is to generate error messages
3520 for assignments that are not allowed in C.
3521 ERRTYPE says whether it is argument passing, assignment,
3522 initialization or return.
3524 FUNCTION is a tree for the function being called.
3525 PARMNUM is the number of the argument, for printing in error messages. */
3528 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3529 tree fundecl, tree function, int parmnum)
3531 enum tree_code codel = TREE_CODE (type);
3533 enum tree_code coder;
3534 tree rname = NULL_TREE;
3536 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3539 /* Change pointer to function to the function itself for
3541 if (TREE_CODE (function) == ADDR_EXPR
3542 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3543 function = TREE_OPERAND (function, 0);
3545 /* Handle an ObjC selector specially for diagnostics. */
3546 selector = objc_message_selector ();
3548 if (selector && parmnum > 2)
3555 /* This macro is used to emit diagnostics to ensure that all format
3556 strings are complete sentences, visible to gettext and checked at
3558 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3563 pedwarn (AR, parmnum, rname); \
3565 case ic_argpass_nonproto: \
3566 warning (0, AR, parmnum, rname); \
3578 gcc_unreachable (); \
3582 STRIP_TYPE_NOPS (rhs);
3584 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3585 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3586 rhs = default_conversion (rhs);
3587 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3588 rhs = decl_constant_value_for_broken_optimization (rhs);
3590 rhstype = TREE_TYPE (rhs);
3591 coder = TREE_CODE (rhstype);
3593 if (coder == ERROR_MARK)
3594 return error_mark_node;
3596 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3598 overflow_warning (rhs);
3599 /* Check for Objective-C protocols. This will automatically
3600 issue a warning if there are protocol violations. No need to
3601 use the return value. */
3602 if (c_dialect_objc ())
3603 objc_comptypes (type, rhstype, 0);
3607 if (coder == VOID_TYPE)
3609 /* Except for passing an argument to an unprototyped function,
3610 this is a constraint violation. When passing an argument to
3611 an unprototyped function, it is compile-time undefined;
3612 making it a constraint in that case was rejected in
3614 error ("void value not ignored as it ought to be");
3615 return error_mark_node;
3617 /* A type converts to a reference to it.
3618 This code doesn't fully support references, it's just for the
3619 special case of va_start and va_copy. */
3620 if (codel == REFERENCE_TYPE
3621 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3623 if (!lvalue_p (rhs))
3625 error ("cannot pass rvalue to reference parameter");
3626 return error_mark_node;
3628 if (!c_mark_addressable (rhs))
3629 return error_mark_node;
3630 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3632 /* We already know that these two types are compatible, but they
3633 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3634 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3635 likely to be va_list, a typedef to __builtin_va_list, which
3636 is different enough that it will cause problems later. */
3637 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3638 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3640 rhs = build1 (NOP_EXPR, type, rhs);
3643 /* Some types can interconvert without explicit casts. */
3644 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3645 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3646 return convert (type, rhs);
3647 /* Arithmetic types all interconvert, and enum is treated like int. */
3648 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3649 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3650 || codel == BOOLEAN_TYPE)
3651 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3652 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3653 || coder == BOOLEAN_TYPE))
3654 return convert_and_check (type, rhs);
3656 /* Conversion to a transparent union from its member types.
3657 This applies only to function arguments. */
3658 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3659 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3662 tree marginal_memb_type = 0;
3664 for (memb_types = TYPE_FIELDS (type); memb_types;
3665 memb_types = TREE_CHAIN (memb_types))
3667 tree memb_type = TREE_TYPE (memb_types);
3669 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3670 TYPE_MAIN_VARIANT (rhstype)))
3673 if (TREE_CODE (memb_type) != POINTER_TYPE)
3676 if (coder == POINTER_TYPE)
3678 tree ttl = TREE_TYPE (memb_type);
3679 tree ttr = TREE_TYPE (rhstype);
3681 /* Any non-function converts to a [const][volatile] void *
3682 and vice versa; otherwise, targets must be the same.
3683 Meanwhile, the lhs target must have all the qualifiers of
3685 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3686 || comp_target_types (memb_type, rhstype, 0))
3688 /* If this type won't generate any warnings, use it. */
3689 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3690 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3691 && TREE_CODE (ttl) == FUNCTION_TYPE)
3692 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3693 == TYPE_QUALS (ttr))
3694 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3695 == TYPE_QUALS (ttl))))
3698 /* Keep looking for a better type, but remember this one. */
3699 if (!marginal_memb_type)
3700 marginal_memb_type = memb_type;
3704 /* Can convert integer zero to any pointer type. */
3705 if (integer_zerop (rhs)
3706 || (TREE_CODE (rhs) == NOP_EXPR
3707 && integer_zerop (TREE_OPERAND (rhs, 0))))
3709 rhs = null_pointer_node;
3714 if (memb_types || marginal_memb_type)
3718 /* We have only a marginally acceptable member type;
3719 it needs a warning. */
3720 tree ttl = TREE_TYPE (marginal_memb_type);
3721 tree ttr = TREE_TYPE (rhstype);
3723 /* Const and volatile mean something different for function
3724 types, so the usual warnings are not appropriate. */
3725 if (TREE_CODE (ttr) == FUNCTION_TYPE
3726 && TREE_CODE (ttl) == FUNCTION_TYPE)
3728 /* Because const and volatile on functions are
3729 restrictions that say the function will not do
3730 certain things, it is okay to use a const or volatile
3731 function where an ordinary one is wanted, but not
3733 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3734 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE "
3735 "makes qualified function "
3736 "pointer from unqualified"),
3737 N_("assignment makes qualified "
3738 "function pointer from "
3740 N_("initialization makes qualified "
3741 "function pointer from "
3743 N_("return makes qualified function "
3744 "pointer from unqualified"));
3746 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3747 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3748 "qualifiers from pointer target type"),
3749 N_("assignment discards qualifiers "
3750 "from pointer target type"),
3751 N_("initialization discards qualifiers "
3752 "from pointer target type"),
3753 N_("return discards qualifiers from "
3754 "pointer target type"));
3757 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3758 pedwarn ("ISO C prohibits argument conversion to union type");
3760 return build1 (NOP_EXPR, type, rhs);
3764 /* Conversions among pointers */
3765 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3766 && (coder == codel))
3768 tree ttl = TREE_TYPE (type);
3769 tree ttr = TREE_TYPE (rhstype);
3772 bool is_opaque_pointer;
3773 int target_cmp = 0; /* Cache comp_target_types () result. */
3775 if (TREE_CODE (mvl) != ARRAY_TYPE)
3776 mvl = TYPE_MAIN_VARIANT (mvl);
3777 if (TREE_CODE (mvr) != ARRAY_TYPE)
3778 mvr = TYPE_MAIN_VARIANT (mvr);
3779 /* Opaque pointers are treated like void pointers. */
3780 is_opaque_pointer = (targetm.vector_opaque_p (type)
3781 || targetm.vector_opaque_p (rhstype))
3782 && TREE_CODE (ttl) == VECTOR_TYPE
3783 && TREE_CODE (ttr) == VECTOR_TYPE;
3785 /* Any non-function converts to a [const][volatile] void *
3786 and vice versa; otherwise, targets must be the same.
3787 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3788 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3789 || (target_cmp = comp_target_types (type, rhstype, 0))
3790 || is_opaque_pointer
3791 || (c_common_unsigned_type (mvl)
3792 == c_common_unsigned_type (mvr)))
3795 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3798 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3799 which are not ANSI null ptr constants. */
3800 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3801 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3802 WARN_FOR_ASSIGNMENT (N_("ISO C forbids passing argument %d of "
3803 "%qE between function pointer "
3805 N_("ISO C forbids assignment between "
3806 "function pointer and %<void *%>"),
3807 N_("ISO C forbids initialization between "
3808 "function pointer and %<void *%>"),
3809 N_("ISO C forbids return between function "
3810 "pointer and %<void *%>"));
3811 /* Const and volatile mean something different for function types,
3812 so the usual warnings are not appropriate. */
3813 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3814 && TREE_CODE (ttl) != FUNCTION_TYPE)
3816 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3817 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE discards "
3818 "qualifiers from pointer target type"),
3819 N_("assignment discards qualifiers "
3820 "from pointer target type"),
3821 N_("initialization discards qualifiers "
3822 "from pointer target type"),
3823 N_("return discards qualifiers from "
3824 "pointer target type"));
3825 /* If this is not a case of ignoring a mismatch in signedness,
3827 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3830 /* If there is a mismatch, do warn. */
3831 else if (warn_pointer_sign)
3832 WARN_FOR_ASSIGNMENT (N_("pointer targets in passing argument "
3833 "%d of %qE differ in signedness"),
3834 N_("pointer targets in assignment "
3835 "differ in signedness"),
3836 N_("pointer targets in initialization "
3837 "differ in signedness"),
3838 N_("pointer targets in return differ "
3841 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3842 && TREE_CODE (ttr) == FUNCTION_TYPE)
3844 /* Because const and volatile on functions are restrictions
3845 that say the function will not do certain things,
3846 it is okay to use a const or volatile function
3847 where an ordinary one is wanted, but not vice-versa. */
3848 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3849 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3850 "qualified function pointer "
3851 "from unqualified"),
3852 N_("assignment makes qualified function "
3853 "pointer from unqualified"),
3854 N_("initialization makes qualified "
3855 "function pointer from unqualified"),
3856 N_("return makes qualified function "
3857 "pointer from unqualified"));
3861 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE from "
3862 "incompatible pointer type"),
3863 N_("assignment from incompatible pointer type"),
3864 N_("initialization from incompatible "
3866 N_("return from incompatible pointer type"));
3867 return convert (type, rhs);
3869 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3871 /* ??? This should not be an error when inlining calls to
3872 unprototyped functions. */
3873 error ("invalid use of non-lvalue array");
3874 return error_mark_node;
3876 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3878 /* An explicit constant 0 can convert to a pointer,
3879 or one that results from arithmetic, even including
3880 a cast to integer type. */
3881 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3883 !(TREE_CODE (rhs) == NOP_EXPR
3884 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3885 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3886 && integer_zerop (TREE_OPERAND (rhs, 0))))
3887 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes "
3888 "pointer from integer without a cast"),
3889 N_("assignment makes pointer from integer "
3891 N_("initialization makes pointer from "
3892 "integer without a cast"),
3893 N_("return makes pointer from integer "
3896 return convert (type, rhs);
3898 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3900 WARN_FOR_ASSIGNMENT (N_("passing argument %d of %qE makes integer "
3901 "from pointer without a cast"),
3902 N_("assignment makes integer from pointer "
3904 N_("initialization makes integer from pointer "
3906 N_("return makes integer from pointer "
3908 return convert (type, rhs);
3910 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3911 return convert (type, rhs);
3916 case ic_argpass_nonproto:
3917 /* ??? This should not be an error when inlining calls to
3918 unprototyped functions. */
3919 error ("incompatible type for argument %d of %qE", parmnum, rname);
3922 error ("incompatible types in assignment");
3925 error ("incompatible types in initialization");
3928 error ("incompatible types in return");
3934 return error_mark_node;
3937 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3938 is used for error and waring reporting and indicates which argument
3939 is being processed. */
3942 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3946 /* If FN was prototyped, the value has been converted already
3947 in convert_arguments. */
3948 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3951 type = TREE_TYPE (parm);
3952 ret = convert_for_assignment (type, value,
3953 ic_argpass_nonproto, fn,
3955 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3956 && INTEGRAL_TYPE_P (type)
3957 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3958 ret = default_conversion (ret);
3962 /* If VALUE is a compound expr all of whose expressions are constant, then
3963 return its value. Otherwise, return error_mark_node.
3965 This is for handling COMPOUND_EXPRs as initializer elements
3966 which is allowed with a warning when -pedantic is specified. */
3969 valid_compound_expr_initializer (tree value, tree endtype)
3971 if (TREE_CODE (value) == COMPOUND_EXPR)
3973 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3975 return error_mark_node;
3976 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3979 else if (!initializer_constant_valid_p (value, endtype))
3980 return error_mark_node;
3985 /* Perform appropriate conversions on the initial value of a variable,
3986 store it in the declaration DECL,
3987 and print any error messages that are appropriate.
3988 If the init is invalid, store an ERROR_MARK. */
3991 store_init_value (tree decl, tree init)
3995 /* If variable's type was invalidly declared, just ignore it. */
3997 type = TREE_TYPE (decl);
3998 if (TREE_CODE (type) == ERROR_MARK)
4001 /* Digest the specified initializer into an expression. */
4003 value = digest_init (type, init, true, TREE_STATIC (decl));
4005 /* Store the expression if valid; else report error. */
4007 if (warn_traditional && !in_system_header
4008 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4009 warning (0, "traditional C rejects automatic aggregate initialization");
4011 DECL_INITIAL (decl) = value;
4013 /* ANSI wants warnings about out-of-range constant initializers. */
4014 STRIP_TYPE_NOPS (value);
4015 constant_expression_warning (value);
4017 /* Check if we need to set array size from compound literal size. */
4018 if (TREE_CODE (type) == ARRAY_TYPE
4019 && TYPE_DOMAIN (type) == 0
4020 && value != error_mark_node)
4022 tree inside_init = init;
4024 STRIP_TYPE_NOPS (inside_init);
4025 inside_init = fold (inside_init);
4027 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4029 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4031 if (TYPE_DOMAIN (TREE_TYPE (decl)))
4033 /* For int foo[] = (int [3]){1}; we need to set array size
4034 now since later on array initializer will be just the
4035 brace enclosed list of the compound literal. */
4036 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
4038 layout_decl (decl, 0);
4044 /* Methods for storing and printing names for error messages. */
4046 /* Implement a spelling stack that allows components of a name to be pushed
4047 and popped. Each element on the stack is this structure. */
4059 #define SPELLING_STRING 1
4060 #define SPELLING_MEMBER 2
4061 #define SPELLING_BOUNDS 3
4063 static struct spelling *spelling; /* Next stack element (unused). */
4064 static struct spelling *spelling_base; /* Spelling stack base. */
4065 static int spelling_size; /* Size of the spelling stack. */
4067 /* Macros to save and restore the spelling stack around push_... functions.
4068 Alternative to SAVE_SPELLING_STACK. */
4070 #define SPELLING_DEPTH() (spelling - spelling_base)
4071 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4073 /* Push an element on the spelling stack with type KIND and assign VALUE
4076 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4078 int depth = SPELLING_DEPTH (); \
4080 if (depth >= spelling_size) \
4082 spelling_size += 10; \
4083 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4085 RESTORE_SPELLING_DEPTH (depth); \
4088 spelling->kind = (KIND); \
4089 spelling->MEMBER = (VALUE); \
4093 /* Push STRING on the stack. Printed literally. */
4096 push_string (const char *string)
4098 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4101 /* Push a member name on the stack. Printed as '.' STRING. */
4104 push_member_name (tree decl)
4106 const char *const string
4107 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4108 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4111 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4114 push_array_bounds (int bounds)
4116 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4119 /* Compute the maximum size in bytes of the printed spelling. */
4122 spelling_length (void)
4127 for (p = spelling_base; p < spelling; p++)
4129 if (p->kind == SPELLING_BOUNDS)
4132 size += strlen (p->u.s) + 1;
4138 /* Print the spelling to BUFFER and return it. */
4141 print_spelling (char *buffer)
4146 for (p = spelling_base; p < spelling; p++)
4147 if (p->kind == SPELLING_BOUNDS)
4149 sprintf (d, "[%d]", p->u.i);
4155 if (p->kind == SPELLING_MEMBER)
4157 for (s = p->u.s; (*d = *s++); d++)
4164 /* Issue an error message for a bad initializer component.
4165 MSGID identifies the message.
4166 The component name is taken from the spelling stack. */
4169 error_init (const char *msgid)
4173 error ("%s", _(msgid));
4174 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4176 error ("(near initialization for %qs)", ofwhat);
4179 /* Issue a pedantic warning for a bad initializer component.
4180 MSGID identifies the message.
4181 The component name is taken from the spelling stack. */
4184 pedwarn_init (const char *msgid)
4188 pedwarn ("%s", _(msgid));
4189 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4191 pedwarn ("(near initialization for %qs)", ofwhat);
4194 /* Issue a warning for a bad initializer component.
4195 MSGID identifies the message.
4196 The component name is taken from the spelling stack. */
4199 warning_init (const char *msgid)
4203 warning (0, "%s", _(msgid));
4204 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4206 warning (0, "(near initialization for %qs)", ofwhat);
4209 /* If TYPE is an array type and EXPR is a parenthesized string
4210 constant, warn if pedantic that EXPR is being used to initialize an
4211 object of type TYPE. */
4214 maybe_warn_string_init (tree type, struct c_expr expr)
4217 && TREE_CODE (type) == ARRAY_TYPE
4218 && TREE_CODE (expr.value) == STRING_CST
4219 && expr.original_code != STRING_CST)
4220 pedwarn_init ("array initialized from parenthesized string constant");
4223 /* Digest the parser output INIT as an initializer for type TYPE.
4224 Return a C expression of type TYPE to represent the initial value.
4226 If INIT is a string constant, STRICT_STRING is true if it is
4227 unparenthesized or we should not warn here for it being parenthesized.
4228 For other types of INIT, STRICT_STRING is not used.
4230 REQUIRE_CONSTANT requests an error if non-constant initializers or
4231 elements are seen. */
4234 digest_init (tree type, tree init, bool strict_string, int require_constant)
4236 enum tree_code code = TREE_CODE (type);
4237 tree inside_init = init;
4239 if (type == error_mark_node
4240 || init == error_mark_node
4241 || TREE_TYPE (init) == error_mark_node)
4242 return error_mark_node;
4244 STRIP_TYPE_NOPS (inside_init);
4246 inside_init = fold (inside_init);
4248 /* Initialization of an array of chars from a string constant
4249 optionally enclosed in braces. */
4251 if (code == ARRAY_TYPE && inside_init
4252 && TREE_CODE (inside_init) == STRING_CST)
4254 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4255 /* Note that an array could be both an array of character type
4256 and an array of wchar_t if wchar_t is signed char or unsigned
4258 bool char_array = (typ1 == char_type_node
4259 || typ1 == signed_char_type_node
4260 || typ1 == unsigned_char_type_node);
4261 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4262 if (char_array || wchar_array)
4266 expr.value = inside_init;
4267 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4268 maybe_warn_string_init (type, expr);
4271 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4274 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4275 TYPE_MAIN_VARIANT (type)))
4278 if (!wchar_array && !char_string)
4280 error_init ("char-array initialized from wide string");
4281 return error_mark_node;
4283 if (char_string && !char_array)
4285 error_init ("wchar_t-array initialized from non-wide string");
4286 return error_mark_node;
4289 TREE_TYPE (inside_init) = type;
4290 if (TYPE_DOMAIN (type) != 0
4291 && TYPE_SIZE (type) != 0
4292 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4293 /* Subtract 1 (or sizeof (wchar_t))
4294 because it's ok to ignore the terminating null char
4295 that is counted in the length of the constant. */
4296 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4297 TREE_STRING_LENGTH (inside_init)
4298 - ((TYPE_PRECISION (typ1)
4299 != TYPE_PRECISION (char_type_node))
4300 ? (TYPE_PRECISION (wchar_type_node)
4303 pedwarn_init ("initializer-string for array of chars is too long");
4307 else if (INTEGRAL_TYPE_P (typ1))
4309 error_init ("array of inappropriate type initialized "
4310 "from string constant");
4311 return error_mark_node;
4315 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4316 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4317 below and handle as a constructor. */
4318 if (code == VECTOR_TYPE
4319 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4320 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4321 && TREE_CONSTANT (inside_init))
4323 if (TREE_CODE (inside_init) == VECTOR_CST
4324 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4325 TYPE_MAIN_VARIANT (type)))
4328 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4332 /* Iterate through elements and check if all constructor
4333 elements are *_CSTs. */
4334 for (link = CONSTRUCTOR_ELTS (inside_init);
4336 link = TREE_CHAIN (link))
4337 if (! CONSTANT_CLASS_P (TREE_VALUE (link)))
4341 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4345 /* Any type can be initialized
4346 from an expression of the same type, optionally with braces. */
4348 if (inside_init && TREE_TYPE (inside_init) != 0
4349 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4350 TYPE_MAIN_VARIANT (type))
4351 || (code == ARRAY_TYPE
4352 && comptypes (TREE_TYPE (inside_init), type))
4353 || (code == VECTOR_TYPE
4354 && comptypes (TREE_TYPE (inside_init), type))
4355 || (code == POINTER_TYPE
4356 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4357 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4359 || (code == POINTER_TYPE
4360 && TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE
4361 && comptypes (TREE_TYPE (inside_init),
4362 TREE_TYPE (type)))))
4364 if (code == POINTER_TYPE)
4366 inside_init = default_function_array_conversion (inside_init);
4368 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4370 error_init ("invalid use of non-lvalue array");
4371 return error_mark_node;
4375 if (code == VECTOR_TYPE)
4376 /* Although the types are compatible, we may require a
4378 inside_init = convert (type, inside_init);
4380 if (require_constant && !flag_isoc99
4381 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4383 /* As an extension, allow initializing objects with static storage
4384 duration with compound literals (which are then treated just as
4385 the brace enclosed list they contain). */
4386 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4387 inside_init = DECL_INITIAL (decl);
4390 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4391 && TREE_CODE (inside_init) != CONSTRUCTOR)
4393 error_init ("array initialized from non-constant array expression");
4394 return error_mark_node;
4397 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4398 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4400 /* Compound expressions can only occur here if -pedantic or
4401 -pedantic-errors is specified. In the later case, we always want
4402 an error. In the former case, we simply want a warning. */
4403 if (require_constant && pedantic
4404 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4407 = valid_compound_expr_initializer (inside_init,
4408 TREE_TYPE (inside_init));
4409 if (inside_init == error_mark_node)
4410 error_init ("initializer element is not constant");
4412 pedwarn_init ("initializer element is not constant");
4413 if (flag_pedantic_errors)
4414 inside_init = error_mark_node;
4416 else if (require_constant
4417 && !initializer_constant_valid_p (inside_init,
4418 TREE_TYPE (inside_init)))
4420 error_init ("initializer element is not constant");
4421 inside_init = error_mark_node;
4427 /* Handle scalar types, including conversions. */
4429 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4430 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4431 || code == VECTOR_TYPE)
4433 /* Note that convert_for_assignment calls default_conversion
4434 for arrays and functions. We must not call it in the
4435 case where inside_init is a null pointer constant. */
4437 = convert_for_assignment (type, init, ic_init,
4438 NULL_TREE, NULL_TREE, 0);
4440 /* Check to see if we have already given an error message. */
4441 if (inside_init == error_mark_node)
4443 else if (require_constant && !TREE_CONSTANT (inside_init))
4445 error_init ("initializer element is not constant");
4446 inside_init = error_mark_node;
4448 else if (require_constant
4449 && !initializer_constant_valid_p (inside_init,
4450 TREE_TYPE (inside_init)))
4452 error_init ("initializer element is not computable at load time");
4453 inside_init = error_mark_node;
4459 /* Come here only for records and arrays. */
4461 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4463 error_init ("variable-sized object may not be initialized");
4464 return error_mark_node;
4467 error_init ("invalid initializer");
4468 return error_mark_node;
4471 /* Handle initializers that use braces. */
4473 /* Type of object we are accumulating a constructor for.
4474 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4475 static tree constructor_type;
4477 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4479 static tree constructor_fields;
4481 /* For an ARRAY_TYPE, this is the specified index
4482 at which to store the next element we get. */
4483 static tree constructor_index;
4485 /* For an ARRAY_TYPE, this is the maximum index. */
4486 static tree constructor_max_index;
4488 /* For a RECORD_TYPE, this is the first field not yet written out. */
4489 static tree constructor_unfilled_fields;
4491 /* For an ARRAY_TYPE, this is the index of the first element
4492 not yet written out. */
4493 static tree constructor_unfilled_index;
4495 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4496 This is so we can generate gaps between fields, when appropriate. */
4497 static tree constructor_bit_index;
4499 /* If we are saving up the elements rather than allocating them,
4500 this is the list of elements so far (in reverse order,
4501 most recent first). */
4502 static tree constructor_elements;
4504 /* 1 if constructor should be incrementally stored into a constructor chain,
4505 0 if all the elements should be kept in AVL tree. */
4506 static int constructor_incremental;
4508 /* 1 if so far this constructor's elements are all compile-time constants. */
4509 static int constructor_constant;
4511 /* 1 if so far this constructor's elements are all valid address constants. */
4512 static int constructor_simple;
4514 /* 1 if this constructor is erroneous so far. */
4515 static int constructor_erroneous;
4517 /* Structure for managing pending initializer elements, organized as an
4522 struct init_node *left, *right;
4523 struct init_node *parent;
4529 /* Tree of pending elements at this constructor level.
4530 These are elements encountered out of order
4531 which belong at places we haven't reached yet in actually
4533 Will never hold tree nodes across GC runs. */
4534 static struct init_node *constructor_pending_elts;
4536 /* The SPELLING_DEPTH of this constructor. */
4537 static int constructor_depth;
4539 /* DECL node for which an initializer is being read.
4540 0 means we are reading a constructor expression
4541 such as (struct foo) {...}. */
4542 static tree constructor_decl;
4544 /* Nonzero if this is an initializer for a top-level decl. */
4545 static int constructor_top_level;
4547 /* Nonzero if there were any member designators in this initializer. */
4548 static int constructor_designated;
4550 /* Nesting depth of designator list. */
4551 static int designator_depth;
4553 /* Nonzero if there were diagnosed errors in this designator list. */
4554 static int designator_errorneous;
4557 /* This stack has a level for each implicit or explicit level of
4558 structuring in the initializer, including the outermost one. It
4559 saves the values of most of the variables above. */
4561 struct constructor_range_stack;
4563 struct constructor_stack
4565 struct constructor_stack *next;
4570 tree unfilled_index;
4571 tree unfilled_fields;
4574 struct init_node *pending_elts;
4577 /* If value nonzero, this value should replace the entire
4578 constructor at this level. */
4579 struct c_expr replacement_value;
4580 struct constructor_range_stack *range_stack;
4590 static struct constructor_stack *constructor_stack;
4592 /* This stack represents designators from some range designator up to
4593 the last designator in the list. */
4595 struct constructor_range_stack
4597 struct constructor_range_stack *next, *prev;
4598 struct constructor_stack *stack;
4605 static struct constructor_range_stack *constructor_range_stack;
4607 /* This stack records separate initializers that are nested.
4608 Nested initializers can't happen in ANSI C, but GNU C allows them
4609 in cases like { ... (struct foo) { ... } ... }. */
4611 struct initializer_stack
4613 struct initializer_stack *next;
4615 struct constructor_stack *constructor_stack;
4616 struct constructor_range_stack *constructor_range_stack;
4618 struct spelling *spelling;
4619 struct spelling *spelling_base;
4622 char require_constant_value;
4623 char require_constant_elements;
4626 static struct initializer_stack *initializer_stack;
4628 /* Prepare to parse and output the initializer for variable DECL. */
4631 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4634 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4636 p->decl = constructor_decl;
4637 p->require_constant_value = require_constant_value;
4638 p->require_constant_elements = require_constant_elements;
4639 p->constructor_stack = constructor_stack;
4640 p->constructor_range_stack = constructor_range_stack;
4641 p->elements = constructor_elements;
4642 p->spelling = spelling;
4643 p->spelling_base = spelling_base;
4644 p->spelling_size = spelling_size;
4645 p->top_level = constructor_top_level;
4646 p->next = initializer_stack;
4647 initializer_stack = p;
4649 constructor_decl = decl;
4650 constructor_designated = 0;
4651 constructor_top_level = top_level;
4653 if (decl != 0 && decl != error_mark_node)
4655 require_constant_value = TREE_STATIC (decl);
4656 require_constant_elements
4657 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4658 /* For a scalar, you can always use any value to initialize,
4659 even within braces. */
4660 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4661 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4662 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4663 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4664 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4668 require_constant_value = 0;
4669 require_constant_elements = 0;
4670 locus = "(anonymous)";
4673 constructor_stack = 0;
4674 constructor_range_stack = 0;
4676 missing_braces_mentioned = 0;
4680 RESTORE_SPELLING_DEPTH (0);
4683 push_string (locus);
4689 struct initializer_stack *p = initializer_stack;
4691 /* Free the whole constructor stack of this initializer. */
4692 while (constructor_stack)
4694 struct constructor_stack *q = constructor_stack;
4695 constructor_stack = q->next;
4699 gcc_assert (!constructor_range_stack);
4701 /* Pop back to the data of the outer initializer (if any). */
4702 free (spelling_base);
4704 constructor_decl = p->decl;
4705 require_constant_value = p->require_constant_value;
4706 require_constant_elements = p->require_constant_elements;
4707 constructor_stack = p->constructor_stack;
4708 constructor_range_stack = p->constructor_range_stack;
4709 constructor_elements = p->elements;
4710 spelling = p->spelling;
4711 spelling_base = p->spelling_base;
4712 spelling_size = p->spelling_size;
4713 constructor_top_level = p->top_level;
4714 initializer_stack = p->next;
4718 /* Call here when we see the initializer is surrounded by braces.
4719 This is instead of a call to push_init_level;
4720 it is matched by a call to pop_init_level.
4722 TYPE is the type to initialize, for a constructor expression.
4723 For an initializer for a decl, TYPE is zero. */
4726 really_start_incremental_init (tree type)
4728 struct constructor_stack *p = XNEW (struct constructor_stack);
4731 type = TREE_TYPE (constructor_decl);
4733 if (targetm.vector_opaque_p (type))
4734 error ("opaque vector types cannot be initialized");
4736 p->type = constructor_type;
4737 p->fields = constructor_fields;
4738 p->index = constructor_index;
4739 p->max_index = constructor_max_index;
4740 p->unfilled_index = constructor_unfilled_index;
4741 p->unfilled_fields = constructor_unfilled_fields;
4742 p->bit_index = constructor_bit_index;
4743 p->elements = constructor_elements;
4744 p->constant = constructor_constant;
4745 p->simple = constructor_simple;
4746 p->erroneous = constructor_erroneous;
4747 p->pending_elts = constructor_pending_elts;
4748 p->depth = constructor_depth;
4749 p->replacement_value.value = 0;
4750 p->replacement_value.original_code = ERROR_MARK;
4754 p->incremental = constructor_incremental;
4755 p->designated = constructor_designated;
4757 constructor_stack = p;
4759 constructor_constant = 1;
4760 constructor_simple = 1;
4761 constructor_depth = SPELLING_DEPTH ();
4762 constructor_elements = 0;
4763 constructor_pending_elts = 0;
4764 constructor_type = type;
4765 constructor_incremental = 1;
4766 constructor_designated = 0;
4767 designator_depth = 0;
4768 designator_errorneous = 0;
4770 if (TREE_CODE (constructor_type) == RECORD_TYPE
4771 || TREE_CODE (constructor_type) == UNION_TYPE)
4773 constructor_fields = TYPE_FIELDS (constructor_type);
4774 /* Skip any nameless bit fields at the beginning. */
4775 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4776 && DECL_NAME (constructor_fields) == 0)
4777 constructor_fields = TREE_CHAIN (constructor_fields);
4779 constructor_unfilled_fields = constructor_fields;
4780 constructor_bit_index = bitsize_zero_node;
4782 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4784 if (TYPE_DOMAIN (constructor_type))
4786 constructor_max_index
4787 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4789 /* Detect non-empty initializations of zero-length arrays. */
4790 if (constructor_max_index == NULL_TREE
4791 && TYPE_SIZE (constructor_type))
4792 constructor_max_index = build_int_cst (NULL_TREE, -1);
4794 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4795 to initialize VLAs will cause a proper error; avoid tree
4796 checking errors as well by setting a safe value. */
4797 if (constructor_max_index
4798 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4799 constructor_max_index = build_int_cst (NULL_TREE, -1);
4802 = convert (bitsizetype,
4803 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4807 constructor_index = bitsize_zero_node;
4808 constructor_max_index = NULL_TREE;
4811 constructor_unfilled_index = constructor_index;
4813 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4815 /* Vectors are like simple fixed-size arrays. */
4816 constructor_max_index =
4817 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4818 constructor_index = convert (bitsizetype, bitsize_zero_node);
4819 constructor_unfilled_index = constructor_index;
4823 /* Handle the case of int x = {5}; */
4824 constructor_fields = constructor_type;
4825 constructor_unfilled_fields = constructor_type;
4829 /* Push down into a subobject, for initialization.
4830 If this is for an explicit set of braces, IMPLICIT is 0.
4831 If it is because the next element belongs at a lower level,
4832 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4835 push_init_level (int implicit)
4837 struct constructor_stack *p;
4838 tree value = NULL_TREE;
4840 /* If we've exhausted any levels that didn't have braces,
4842 while (constructor_stack->implicit)
4844 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4845 || TREE_CODE (constructor_type) == UNION_TYPE)
4846 && constructor_fields == 0)
4847 process_init_element (pop_init_level (1));
4848 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4849 && constructor_max_index
4850 && tree_int_cst_lt (constructor_max_index, constructor_index))
4851 process_init_element (pop_init_level (1));
4856 /* Unless this is an explicit brace, we need to preserve previous
4860 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4861 || TREE_CODE (constructor_type) == UNION_TYPE)
4862 && constructor_fields)
4863 value = find_init_member (constructor_fields);
4864 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4865 value = find_init_member (constructor_index);
4868 p = XNEW (struct constructor_stack);
4869 p->type = constructor_type;
4870 p->fields = constructor_fields;
4871 p->index = constructor_index;
4872 p->max_index = constructor_max_index;
4873 p->unfilled_index = constructor_unfilled_index;
4874 p->unfilled_fields = constructor_unfilled_fields;
4875 p->bit_index = constructor_bit_index;
4876 p->elements = constructor_elements;
4877 p->constant = constructor_constant;
4878 p->simple = constructor_simple;
4879 p->erroneous = constructor_erroneous;
4880 p->pending_elts = constructor_pending_elts;
4881 p->depth = constructor_depth;
4882 p->replacement_value.value = 0;
4883 p->replacement_value.original_code = ERROR_MARK;
4884 p->implicit = implicit;
4886 p->incremental = constructor_incremental;
4887 p->designated = constructor_designated;
4888 p->next = constructor_stack;
4890 constructor_stack = p;
4892 constructor_constant = 1;
4893 constructor_simple = 1;
4894 constructor_depth = SPELLING_DEPTH ();
4895 constructor_elements = 0;
4896 constructor_incremental = 1;
4897 constructor_designated = 0;
4898 constructor_pending_elts = 0;
4901 p->range_stack = constructor_range_stack;
4902 constructor_range_stack = 0;
4903 designator_depth = 0;
4904 designator_errorneous = 0;
4907 /* Don't die if an entire brace-pair level is superfluous
4908 in the containing level. */
4909 if (constructor_type == 0)
4911 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4912 || TREE_CODE (constructor_type) == UNION_TYPE)
4914 /* Don't die if there are extra init elts at the end. */
4915 if (constructor_fields == 0)
4916 constructor_type = 0;
4919 constructor_type = TREE_TYPE (constructor_fields);
4920 push_member_name (constructor_fields);
4921 constructor_depth++;
4924 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4926 constructor_type = TREE_TYPE (constructor_type);
4927 push_array_bounds (tree_low_cst (constructor_index, 0));
4928 constructor_depth++;
4931 if (constructor_type == 0)
4933 error_init ("extra brace group at end of initializer");
4934 constructor_fields = 0;
4935 constructor_unfilled_fields = 0;
4939 if (value && TREE_CODE (value) == CONSTRUCTOR)
4941 constructor_constant = TREE_CONSTANT (value);
4942 constructor_simple = TREE_STATIC (value);
4943 constructor_elements = CONSTRUCTOR_ELTS (value);
4944 if (constructor_elements
4945 && (TREE_CODE (constructor_type) == RECORD_TYPE
4946 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4947 set_nonincremental_init ();
4950 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4952 missing_braces_mentioned = 1;
4953 warning_init ("missing braces around initializer");
4956 if (TREE_CODE (constructor_type) == RECORD_TYPE
4957 || TREE_CODE (constructor_type) == UNION_TYPE)
4959 constructor_fields = TYPE_FIELDS (constructor_type);
4960 /* Skip any nameless bit fields at the beginning. */
4961 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4962 && DECL_NAME (constructor_fields) == 0)
4963 constructor_fields = TREE_CHAIN (constructor_fields);
4965 constructor_unfilled_fields = constructor_fields;
4966 constructor_bit_index = bitsize_zero_node;
4968 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4970 /* Vectors are like simple fixed-size arrays. */
4971 constructor_max_index =
4972 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4973 constructor_index = convert (bitsizetype, integer_zero_node);
4974 constructor_unfilled_index = constructor_index;
4976 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4978 if (TYPE_DOMAIN (constructor_type))
4980 constructor_max_index
4981 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4983 /* Detect non-empty initializations of zero-length arrays. */
4984 if (constructor_max_index == NULL_TREE
4985 && TYPE_SIZE (constructor_type))
4986 constructor_max_index = build_int_cst (NULL_TREE, -1);
4988 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4989 to initialize VLAs will cause a proper error; avoid tree
4990 checking errors as well by setting a safe value. */
4991 if (constructor_max_index
4992 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4993 constructor_max_index = build_int_cst (NULL_TREE, -1);
4996 = convert (bitsizetype,
4997 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5000 constructor_index = bitsize_zero_node;
5002 constructor_unfilled_index = constructor_index;
5003 if (value && TREE_CODE (value) == STRING_CST)
5005 /* We need to split the char/wchar array into individual
5006 characters, so that we don't have to special case it
5008 set_nonincremental_init_from_string (value);
5013 if (constructor_type != error_mark_node)
5014 warning_init ("braces around scalar initializer");
5015 constructor_fields = constructor_type;
5016 constructor_unfilled_fields = constructor_type;
5020 /* At the end of an implicit or explicit brace level,
5021 finish up that level of constructor. If a single expression
5022 with redundant braces initialized that level, return the
5023 c_expr structure for that expression. Otherwise, the original_code
5024 element is set to ERROR_MARK.
5025 If we were outputting the elements as they are read, return 0 as the value
5026 from inner levels (process_init_element ignores that),
5027 but return error_mark_node as the value from the outermost level
5028 (that's what we want to put in DECL_INITIAL).
5029 Otherwise, return a CONSTRUCTOR expression as the value. */
5032 pop_init_level (int implicit)
5034 struct constructor_stack *p;
5037 ret.original_code = ERROR_MARK;
5041 /* When we come to an explicit close brace,
5042 pop any inner levels that didn't have explicit braces. */
5043 while (constructor_stack->implicit)
5044 process_init_element (pop_init_level (1));
5046 gcc_assert (!constructor_range_stack);
5049 /* Now output all pending elements. */
5050 constructor_incremental = 1;
5051 output_pending_init_elements (1);
5053 p = constructor_stack;
5055 /* Error for initializing a flexible array member, or a zero-length
5056 array member in an inappropriate context. */
5057 if (constructor_type && constructor_fields
5058 && TREE_CODE (constructor_type) == ARRAY_TYPE
5059 && TYPE_DOMAIN (constructor_type)
5060 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5062 /* Silently discard empty initializations. The parser will
5063 already have pedwarned for empty brackets. */
5064 if (integer_zerop (constructor_unfilled_index))
5065 constructor_type = NULL_TREE;
5068 gcc_assert (!TYPE_SIZE (constructor_type));
5070 if (constructor_depth > 2)
5071 error_init ("initialization of flexible array member in a nested context");
5073 pedwarn_init ("initialization of a flexible array member");
5075 /* We have already issued an error message for the existence
5076 of a flexible array member not at the end of the structure.
5077 Discard the initializer so that we do not die later. */
5078 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5079 constructor_type = NULL_TREE;
5083 /* Warn when some struct elements are implicitly initialized to zero. */
5084 if (warn_missing_field_initializers
5086 && TREE_CODE (constructor_type) == RECORD_TYPE
5087 && constructor_unfilled_fields)
5089 /* Do not warn for flexible array members or zero-length arrays. */
5090 while (constructor_unfilled_fields
5091 && (!DECL_SIZE (constructor_unfilled_fields)
5092 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5093 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5095 /* Do not warn if this level of the initializer uses member
5096 designators; it is likely to be deliberate. */
5097 if (constructor_unfilled_fields && !constructor_designated)
5099 push_member_name (constructor_unfilled_fields);
5100 warning_init ("missing initializer");
5101 RESTORE_SPELLING_DEPTH (constructor_depth);
5105 /* Pad out the end of the structure. */
5106 if (p->replacement_value.value)
5107 /* If this closes a superfluous brace pair,
5108 just pass out the element between them. */
5109 ret = p->replacement_value;
5110 else if (constructor_type == 0)
5112 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5113 && TREE_CODE (constructor_type) != UNION_TYPE
5114 && TREE_CODE (constructor_type) != ARRAY_TYPE
5115 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5117 /* A nonincremental scalar initializer--just return
5118 the element, after verifying there is just one. */
5119 if (constructor_elements == 0)
5121 if (!constructor_erroneous)
5122 error_init ("empty scalar initializer");
5123 ret.value = error_mark_node;
5125 else if (TREE_CHAIN (constructor_elements) != 0)
5127 error_init ("extra elements in scalar initializer");
5128 ret.value = TREE_VALUE (constructor_elements);
5131 ret.value = TREE_VALUE (constructor_elements);
5135 if (constructor_erroneous)
5136 ret.value = error_mark_node;
5139 ret.value = build_constructor (constructor_type,
5140 nreverse (constructor_elements));
5141 if (constructor_constant)
5142 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5143 if (constructor_constant && constructor_simple)
5144 TREE_STATIC (ret.value) = 1;
5148 constructor_type = p->type;
5149 constructor_fields = p->fields;
5150 constructor_index = p->index;
5151 constructor_max_index = p->max_index;
5152 constructor_unfilled_index = p->unfilled_index;
5153 constructor_unfilled_fields = p->unfilled_fields;
5154 constructor_bit_index = p->bit_index;
5155 constructor_elements = p->elements;
5156 constructor_constant = p->constant;
5157 constructor_simple = p->simple;
5158 constructor_erroneous = p->erroneous;
5159 constructor_incremental = p->incremental;
5160 constructor_designated = p->designated;
5161 constructor_pending_elts = p->pending_elts;
5162 constructor_depth = p->depth;
5164 constructor_range_stack = p->range_stack;
5165 RESTORE_SPELLING_DEPTH (constructor_depth);
5167 constructor_stack = p->next;
5172 if (constructor_stack == 0)
5174 ret.value = error_mark_node;
5182 /* Common handling for both array range and field name designators.
5183 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5186 set_designator (int array)
5189 enum tree_code subcode;
5191 /* Don't die if an entire brace-pair level is superfluous
5192 in the containing level. */
5193 if (constructor_type == 0)
5196 /* If there were errors in this designator list already, bail out
5198 if (designator_errorneous)
5201 if (!designator_depth)
5203 gcc_assert (!constructor_range_stack);
5205 /* Designator list starts at the level of closest explicit
5207 while (constructor_stack->implicit)
5208 process_init_element (pop_init_level (1));
5209 constructor_designated = 1;
5213 switch (TREE_CODE (constructor_type))
5217 subtype = TREE_TYPE (constructor_fields);
5218 if (subtype != error_mark_node)
5219 subtype = TYPE_MAIN_VARIANT (subtype);
5222 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5228 subcode = TREE_CODE (subtype);
5229 if (array && subcode != ARRAY_TYPE)
5231 error_init ("array index in non-array initializer");
5234 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5236 error_init ("field name not in record or union initializer");
5240 constructor_designated = 1;
5241 push_init_level (2);
5245 /* If there are range designators in designator list, push a new designator
5246 to constructor_range_stack. RANGE_END is end of such stack range or
5247 NULL_TREE if there is no range designator at this level. */
5250 push_range_stack (tree range_end)
5252 struct constructor_range_stack *p;
5254 p = GGC_NEW (struct constructor_range_stack);
5255 p->prev = constructor_range_stack;
5257 p->fields = constructor_fields;
5258 p->range_start = constructor_index;
5259 p->index = constructor_index;
5260 p->stack = constructor_stack;
5261 p->range_end = range_end;
5262 if (constructor_range_stack)
5263 constructor_range_stack->next = p;
5264 constructor_range_stack = p;
5267 /* Within an array initializer, specify the next index to be initialized.
5268 FIRST is that index. If LAST is nonzero, then initialize a range
5269 of indices, running from FIRST through LAST. */
5272 set_init_index (tree first, tree last)
5274 if (set_designator (1))
5277 designator_errorneous = 1;
5279 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5280 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5282 error_init ("array index in initializer not of integer type");
5286 if (TREE_CODE (first) != INTEGER_CST)
5287 error_init ("nonconstant array index in initializer");
5288 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5289 error_init ("nonconstant array index in initializer");
5290 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5291 error_init ("array index in non-array initializer");
5292 else if (tree_int_cst_sgn (first) == -1)
5293 error_init ("array index in initializer exceeds array bounds");
5294 else if (constructor_max_index
5295 && tree_int_cst_lt (constructor_max_index, first))
5296 error_init ("array index in initializer exceeds array bounds");
5299 constructor_index = convert (bitsizetype, first);
5303 if (tree_int_cst_equal (first, last))
5305 else if (tree_int_cst_lt (last, first))
5307 error_init ("empty index range in initializer");
5312 last = convert (bitsizetype, last);
5313 if (constructor_max_index != 0
5314 && tree_int_cst_lt (constructor_max_index, last))
5316 error_init ("array index range in initializer exceeds array bounds");
5323 designator_errorneous = 0;
5324 if (constructor_range_stack || last)
5325 push_range_stack (last);
5329 /* Within a struct initializer, specify the next field to be initialized. */
5332 set_init_label (tree fieldname)
5336 if (set_designator (0))
5339 designator_errorneous = 1;
5341 if (TREE_CODE (constructor_type) != RECORD_TYPE
5342 && TREE_CODE (constructor_type) != UNION_TYPE)
5344 error_init ("field name not in record or union initializer");
5348 for (tail = TYPE_FIELDS (constructor_type); tail;
5349 tail = TREE_CHAIN (tail))
5351 if (DECL_NAME (tail) == fieldname)
5356 error ("unknown field %qE specified in initializer", fieldname);
5359 constructor_fields = tail;
5361 designator_errorneous = 0;
5362 if (constructor_range_stack)
5363 push_range_stack (NULL_TREE);
5367 /* Add a new initializer to the tree of pending initializers. PURPOSE
5368 identifies the initializer, either array index or field in a structure.
5369 VALUE is the value of that index or field. */
5372 add_pending_init (tree purpose, tree value)
5374 struct init_node *p, **q, *r;
5376 q = &constructor_pending_elts;
5379 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5384 if (tree_int_cst_lt (purpose, p->purpose))
5386 else if (tree_int_cst_lt (p->purpose, purpose))
5390 if (TREE_SIDE_EFFECTS (p->value))
5391 warning_init ("initialized field with side-effects overwritten");
5401 bitpos = bit_position (purpose);
5405 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5407 else if (p->purpose != purpose)
5411 if (TREE_SIDE_EFFECTS (p->value))
5412 warning_init ("initialized field with side-effects overwritten");
5419 r = GGC_NEW (struct init_node);
5420 r->purpose = purpose;
5431 struct init_node *s;
5435 if (p->balance == 0)
5437 else if (p->balance < 0)
5444 p->left->parent = p;
5461 constructor_pending_elts = r;
5466 struct init_node *t = r->right;
5470 r->right->parent = r;
5475 p->left->parent = p;
5478 p->balance = t->balance < 0;
5479 r->balance = -(t->balance > 0);
5494 constructor_pending_elts = t;
5500 /* p->balance == +1; growth of left side balances the node. */
5505 else /* r == p->right */
5507 if (p->balance == 0)
5508 /* Growth propagation from right side. */
5510 else if (p->balance > 0)
5517 p->right->parent = p;
5534 constructor_pending_elts = r;
5536 else /* r->balance == -1 */
5539 struct init_node *t = r->left;
5543 r->left->parent = r;
5548 p->right->parent = p;
5551 r->balance = (t->balance < 0);
5552 p->balance = -(t->balance > 0);
5567 constructor_pending_elts = t;
5573 /* p->balance == -1; growth of right side balances the node. */
5584 /* Build AVL tree from a sorted chain. */
5587 set_nonincremental_init (void)
5591 if (TREE_CODE (constructor_type) != RECORD_TYPE
5592 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5595 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5596 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5597 constructor_elements = 0;
5598 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5600 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5601 /* Skip any nameless bit fields at the beginning. */
5602 while (constructor_unfilled_fields != 0
5603 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5604 && DECL_NAME (constructor_unfilled_fields) == 0)
5605 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5608 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5610 if (TYPE_DOMAIN (constructor_type))
5611 constructor_unfilled_index
5612 = convert (bitsizetype,
5613 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5615 constructor_unfilled_index = bitsize_zero_node;
5617 constructor_incremental = 0;
5620 /* Build AVL tree from a string constant. */
5623 set_nonincremental_init_from_string (tree str)
5625 tree value, purpose, type;
5626 HOST_WIDE_INT val[2];
5627 const char *p, *end;
5628 int byte, wchar_bytes, charwidth, bitpos;
5630 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5632 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5633 == TYPE_PRECISION (char_type_node))
5637 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5638 == TYPE_PRECISION (wchar_type_node));
5639 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5641 charwidth = TYPE_PRECISION (char_type_node);
5642 type = TREE_TYPE (constructor_type);
5643 p = TREE_STRING_POINTER (str);
5644 end = p + TREE_STRING_LENGTH (str);
5646 for (purpose = bitsize_zero_node;
5647 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5648 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5650 if (wchar_bytes == 1)
5652 val[1] = (unsigned char) *p++;
5659 for (byte = 0; byte < wchar_bytes; byte++)
5661 if (BYTES_BIG_ENDIAN)
5662 bitpos = (wchar_bytes - byte - 1) * charwidth;
5664 bitpos = byte * charwidth;
5665 val[bitpos < HOST_BITS_PER_WIDE_INT]
5666 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5667 << (bitpos % HOST_BITS_PER_WIDE_INT);
5671 if (!TYPE_UNSIGNED (type))
5673 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5674 if (bitpos < HOST_BITS_PER_WIDE_INT)
5676 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5678 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5682 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5687 else if (val[0] & (((HOST_WIDE_INT) 1)
5688 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5689 val[0] |= ((HOST_WIDE_INT) -1)
5690 << (bitpos - HOST_BITS_PER_WIDE_INT);
5693 value = build_int_cst_wide (type, val[1], val[0]);
5694 add_pending_init (purpose, value);
5697 constructor_incremental = 0;
5700 /* Return value of FIELD in pending initializer or zero if the field was
5701 not initialized yet. */
5704 find_init_member (tree field)
5706 struct init_node *p;
5708 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5710 if (constructor_incremental
5711 && tree_int_cst_lt (field, constructor_unfilled_index))
5712 set_nonincremental_init ();
5714 p = constructor_pending_elts;
5717 if (tree_int_cst_lt (field, p->purpose))
5719 else if (tree_int_cst_lt (p->purpose, field))
5725 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5727 tree bitpos = bit_position (field);
5729 if (constructor_incremental
5730 && (!constructor_unfilled_fields
5731 || tree_int_cst_lt (bitpos,
5732 bit_position (constructor_unfilled_fields))))
5733 set_nonincremental_init ();
5735 p = constructor_pending_elts;
5738 if (field == p->purpose)
5740 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5746 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5748 if (constructor_elements
5749 && TREE_PURPOSE (constructor_elements) == field)
5750 return TREE_VALUE (constructor_elements);
5755 /* "Output" the next constructor element.
5756 At top level, really output it to assembler code now.
5757 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5758 TYPE is the data type that the containing data type wants here.
5759 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5760 If VALUE is a string constant, STRICT_STRING is true if it is
5761 unparenthesized or we should not warn here for it being parenthesized.
5762 For other types of VALUE, STRICT_STRING is not used.
5764 PENDING if non-nil means output pending elements that belong
5765 right after this element. (PENDING is normally 1;
5766 it is 0 while outputting pending elements, to avoid recursion.) */
5769 output_init_element (tree value, bool strict_string, tree type, tree field,
5772 if (type == error_mark_node || value == error_mark_node)
5774 constructor_erroneous = 1;
5777 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5778 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5779 && !(TREE_CODE (value) == STRING_CST
5780 && TREE_CODE (type) == ARRAY_TYPE
5781 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5782 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5783 TYPE_MAIN_VARIANT (type))))
5784 value = default_conversion (value);
5786 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5787 && require_constant_value && !flag_isoc99 && pending)
5789 /* As an extension, allow initializing objects with static storage
5790 duration with compound literals (which are then treated just as
5791 the brace enclosed list they contain). */
5792 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5793 value = DECL_INITIAL (decl);
5796 if (value == error_mark_node)
5797 constructor_erroneous = 1;
5798 else if (!TREE_CONSTANT (value))
5799 constructor_constant = 0;
5800 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5801 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5802 || TREE_CODE (constructor_type) == UNION_TYPE)
5803 && DECL_C_BIT_FIELD (field)
5804 && TREE_CODE (value) != INTEGER_CST))
5805 constructor_simple = 0;
5807 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5809 if (require_constant_value)
5811 error_init ("initializer element is not constant");
5812 value = error_mark_node;
5814 else if (require_constant_elements)
5815 pedwarn ("initializer element is not computable at load time");
5818 /* If this field is empty (and not at the end of structure),
5819 don't do anything other than checking the initializer. */
5821 && (TREE_TYPE (field) == error_mark_node
5822 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5823 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5824 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5825 || TREE_CHAIN (field)))))
5828 value = digest_init (type, value, strict_string, require_constant_value);
5829 if (value == error_mark_node)
5831 constructor_erroneous = 1;
5835 /* If this element doesn't come next in sequence,
5836 put it on constructor_pending_elts. */
5837 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5838 && (!constructor_incremental
5839 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5841 if (constructor_incremental
5842 && tree_int_cst_lt (field, constructor_unfilled_index))
5843 set_nonincremental_init ();
5845 add_pending_init (field, value);
5848 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5849 && (!constructor_incremental
5850 || field != constructor_unfilled_fields))
5852 /* We do this for records but not for unions. In a union,
5853 no matter which field is specified, it can be initialized
5854 right away since it starts at the beginning of the union. */
5855 if (constructor_incremental)
5857 if (!constructor_unfilled_fields)
5858 set_nonincremental_init ();
5861 tree bitpos, unfillpos;
5863 bitpos = bit_position (field);
5864 unfillpos = bit_position (constructor_unfilled_fields);
5866 if (tree_int_cst_lt (bitpos, unfillpos))
5867 set_nonincremental_init ();
5871 add_pending_init (field, value);
5874 else if (TREE_CODE (constructor_type) == UNION_TYPE
5875 && constructor_elements)
5877 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5878 warning_init ("initialized field with side-effects overwritten");
5880 /* We can have just one union field set. */
5881 constructor_elements = 0;
5884 /* Otherwise, output this element either to
5885 constructor_elements or to the assembler file. */
5887 if (field && TREE_CODE (field) == INTEGER_CST)
5888 field = copy_node (field);
5889 constructor_elements
5890 = tree_cons (field, value, constructor_elements);
5892 /* Advance the variable that indicates sequential elements output. */
5893 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5894 constructor_unfilled_index
5895 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5897 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5899 constructor_unfilled_fields
5900 = TREE_CHAIN (constructor_unfilled_fields);
5902 /* Skip any nameless bit fields. */
5903 while (constructor_unfilled_fields != 0
5904 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5905 && DECL_NAME (constructor_unfilled_fields) == 0)
5906 constructor_unfilled_fields =
5907 TREE_CHAIN (constructor_unfilled_fields);
5909 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5910 constructor_unfilled_fields = 0;
5912 /* Now output any pending elements which have become next. */
5914 output_pending_init_elements (0);
5917 /* Output any pending elements which have become next.
5918 As we output elements, constructor_unfilled_{fields,index}
5919 advances, which may cause other elements to become next;
5920 if so, they too are output.
5922 If ALL is 0, we return when there are
5923 no more pending elements to output now.
5925 If ALL is 1, we output space as necessary so that
5926 we can output all the pending elements. */
5929 output_pending_init_elements (int all)
5931 struct init_node *elt = constructor_pending_elts;
5936 /* Look through the whole pending tree.
5937 If we find an element that should be output now,
5938 output it. Otherwise, set NEXT to the element
5939 that comes first among those still pending. */
5944 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5946 if (tree_int_cst_equal (elt->purpose,
5947 constructor_unfilled_index))
5948 output_init_element (elt->value, true,
5949 TREE_TYPE (constructor_type),
5950 constructor_unfilled_index, 0);
5951 else if (tree_int_cst_lt (constructor_unfilled_index,
5954 /* Advance to the next smaller node. */
5959 /* We have reached the smallest node bigger than the
5960 current unfilled index. Fill the space first. */
5961 next = elt->purpose;
5967 /* Advance to the next bigger node. */
5972 /* We have reached the biggest node in a subtree. Find
5973 the parent of it, which is the next bigger node. */
5974 while (elt->parent && elt->parent->right == elt)
5977 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5980 next = elt->purpose;
5986 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5987 || TREE_CODE (constructor_type) == UNION_TYPE)
5989 tree ctor_unfilled_bitpos, elt_bitpos;
5991 /* If the current record is complete we are done. */
5992 if (constructor_unfilled_fields == 0)
5995 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
5996 elt_bitpos = bit_position (elt->purpose);
5997 /* We can't compare fields here because there might be empty
5998 fields in between. */
5999 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6001 constructor_unfilled_fields = elt->purpose;
6002 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6005 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6007 /* Advance to the next smaller node. */
6012 /* We have reached the smallest node bigger than the
6013 current unfilled field. Fill the space first. */
6014 next = elt->purpose;
6020 /* Advance to the next bigger node. */
6025 /* We have reached the biggest node in a subtree. Find
6026 the parent of it, which is the next bigger node. */
6027 while (elt->parent && elt->parent->right == elt)
6031 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6032 bit_position (elt->purpose))))
6034 next = elt->purpose;
6042 /* Ordinarily return, but not if we want to output all
6043 and there are elements left. */
6044 if (!(all && next != 0))
6047 /* If it's not incremental, just skip over the gap, so that after
6048 jumping to retry we will output the next successive element. */
6049 if (TREE_CODE (constructor_type) == RECORD_TYPE
6050 || TREE_CODE (constructor_type) == UNION_TYPE)
6051 constructor_unfilled_fields = next;
6052 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6053 constructor_unfilled_index = next;
6055 /* ELT now points to the node in the pending tree with the next
6056 initializer to output. */
6060 /* Add one non-braced element to the current constructor level.
6061 This adjusts the current position within the constructor's type.
6062 This may also start or terminate implicit levels
6063 to handle a partly-braced initializer.
6065 Once this has found the correct level for the new element,
6066 it calls output_init_element. */
6069 process_init_element (struct c_expr value)
6071 tree orig_value = value.value;
6072 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6073 bool strict_string = value.original_code == STRING_CST;
6075 designator_depth = 0;
6076 designator_errorneous = 0;
6078 /* Handle superfluous braces around string cst as in
6079 char x[] = {"foo"}; */
6082 && TREE_CODE (constructor_type) == ARRAY_TYPE
6083 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6084 && integer_zerop (constructor_unfilled_index))
6086 if (constructor_stack->replacement_value.value)
6087 error_init ("excess elements in char array initializer");
6088 constructor_stack->replacement_value = value;
6092 if (constructor_stack->replacement_value.value != 0)
6094 error_init ("excess elements in struct initializer");
6098 /* Ignore elements of a brace group if it is entirely superfluous
6099 and has already been diagnosed. */
6100 if (constructor_type == 0)
6103 /* If we've exhausted any levels that didn't have braces,
6105 while (constructor_stack->implicit)
6107 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6108 || TREE_CODE (constructor_type) == UNION_TYPE)
6109 && constructor_fields == 0)
6110 process_init_element (pop_init_level (1));
6111 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6112 && (constructor_max_index == 0
6113 || tree_int_cst_lt (constructor_max_index,
6114 constructor_index)))
6115 process_init_element (pop_init_level (1));
6120 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6121 if (constructor_range_stack)
6123 /* If value is a compound literal and we'll be just using its
6124 content, don't put it into a SAVE_EXPR. */
6125 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6126 || !require_constant_value
6128 value.value = save_expr (value.value);
6133 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6136 enum tree_code fieldcode;
6138 if (constructor_fields == 0)
6140 pedwarn_init ("excess elements in struct initializer");
6144 fieldtype = TREE_TYPE (constructor_fields);
6145 if (fieldtype != error_mark_node)
6146 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6147 fieldcode = TREE_CODE (fieldtype);
6149 /* Error for non-static initialization of a flexible array member. */
6150 if (fieldcode == ARRAY_TYPE
6151 && !require_constant_value
6152 && TYPE_SIZE (fieldtype) == NULL_TREE
6153 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6155 error_init ("non-static initialization of a flexible array member");
6159 /* Accept a string constant to initialize a subarray. */
6160 if (value.value != 0
6161 && fieldcode == ARRAY_TYPE
6162 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6164 value.value = orig_value;
6165 /* Otherwise, if we have come to a subaggregate,
6166 and we don't have an element of its type, push into it. */
6167 else if (value.value != 0
6168 && value.value != error_mark_node
6169 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6170 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6171 || fieldcode == UNION_TYPE))
6173 push_init_level (1);
6179 push_member_name (constructor_fields);
6180 output_init_element (value.value, strict_string,
6181 fieldtype, constructor_fields, 1);
6182 RESTORE_SPELLING_DEPTH (constructor_depth);
6185 /* Do the bookkeeping for an element that was
6186 directly output as a constructor. */
6188 /* For a record, keep track of end position of last field. */
6189 if (DECL_SIZE (constructor_fields))
6190 constructor_bit_index
6191 = size_binop (PLUS_EXPR,
6192 bit_position (constructor_fields),
6193 DECL_SIZE (constructor_fields));
6195 /* If the current field was the first one not yet written out,
6196 it isn't now, so update. */
6197 if (constructor_unfilled_fields == constructor_fields)
6199 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6200 /* Skip any nameless bit fields. */
6201 while (constructor_unfilled_fields != 0
6202 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6203 && DECL_NAME (constructor_unfilled_fields) == 0)
6204 constructor_unfilled_fields =
6205 TREE_CHAIN (constructor_unfilled_fields);
6209 constructor_fields = TREE_CHAIN (constructor_fields);
6210 /* Skip any nameless bit fields at the beginning. */
6211 while (constructor_fields != 0
6212 && DECL_C_BIT_FIELD (constructor_fields)
6213 && DECL_NAME (constructor_fields) == 0)
6214 constructor_fields = TREE_CHAIN (constructor_fields);
6216 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6219 enum tree_code fieldcode;
6221 if (constructor_fields == 0)
6223 pedwarn_init ("excess elements in union initializer");
6227 fieldtype = TREE_TYPE (constructor_fields);
6228 if (fieldtype != error_mark_node)
6229 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6230 fieldcode = TREE_CODE (fieldtype);
6232 /* Warn that traditional C rejects initialization of unions.
6233 We skip the warning if the value is zero. This is done
6234 under the assumption that the zero initializer in user
6235 code appears conditioned on e.g. __STDC__ to avoid
6236 "missing initializer" warnings and relies on default
6237 initialization to zero in the traditional C case.
6238 We also skip the warning if the initializer is designated,
6239 again on the assumption that this must be conditional on
6240 __STDC__ anyway (and we've already complained about the
6241 member-designator already). */
6242 if (warn_traditional && !in_system_header && !constructor_designated
6243 && !(value.value && (integer_zerop (value.value)
6244 || real_zerop (value.value))))
6245 warning (0, "traditional C rejects initialization of unions");
6247 /* Accept a string constant to initialize a subarray. */
6248 if (value.value != 0
6249 && fieldcode == ARRAY_TYPE
6250 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6252 value.value = orig_value;
6253 /* Otherwise, if we have come to a subaggregate,
6254 and we don't have an element of its type, push into it. */
6255 else if (value.value != 0
6256 && value.value != error_mark_node
6257 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6258 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6259 || fieldcode == UNION_TYPE))
6261 push_init_level (1);
6267 push_member_name (constructor_fields);
6268 output_init_element (value.value, strict_string,
6269 fieldtype, constructor_fields, 1);
6270 RESTORE_SPELLING_DEPTH (constructor_depth);
6273 /* Do the bookkeeping for an element that was
6274 directly output as a constructor. */
6276 constructor_bit_index = DECL_SIZE (constructor_fields);
6277 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6280 constructor_fields = 0;
6282 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6284 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6285 enum tree_code eltcode = TREE_CODE (elttype);
6287 /* Accept a string constant to initialize a subarray. */
6288 if (value.value != 0
6289 && eltcode == ARRAY_TYPE
6290 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6292 value.value = orig_value;
6293 /* Otherwise, if we have come to a subaggregate,
6294 and we don't have an element of its type, push into it. */
6295 else if (value.value != 0
6296 && value.value != error_mark_node
6297 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6298 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6299 || eltcode == UNION_TYPE))
6301 push_init_level (1);
6305 if (constructor_max_index != 0
6306 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6307 || integer_all_onesp (constructor_max_index)))
6309 pedwarn_init ("excess elements in array initializer");
6313 /* Now output the actual element. */
6316 push_array_bounds (tree_low_cst (constructor_index, 0));
6317 output_init_element (value.value, strict_string,
6318 elttype, constructor_index, 1);
6319 RESTORE_SPELLING_DEPTH (constructor_depth);
6323 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6326 /* If we are doing the bookkeeping for an element that was
6327 directly output as a constructor, we must update
6328 constructor_unfilled_index. */
6329 constructor_unfilled_index = constructor_index;
6331 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6333 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6335 /* Do a basic check of initializer size. Note that vectors
6336 always have a fixed size derived from their type. */
6337 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6339 pedwarn_init ("excess elements in vector initializer");
6343 /* Now output the actual element. */
6345 output_init_element (value.value, strict_string,
6346 elttype, constructor_index, 1);
6349 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6352 /* If we are doing the bookkeeping for an element that was
6353 directly output as a constructor, we must update
6354 constructor_unfilled_index. */
6355 constructor_unfilled_index = constructor_index;
6358 /* Handle the sole element allowed in a braced initializer
6359 for a scalar variable. */
6360 else if (constructor_type != error_mark_node
6361 && constructor_fields == 0)
6363 pedwarn_init ("excess elements in scalar initializer");
6369 output_init_element (value.value, strict_string,
6370 constructor_type, NULL_TREE, 1);
6371 constructor_fields = 0;
6374 /* Handle range initializers either at this level or anywhere higher
6375 in the designator stack. */
6376 if (constructor_range_stack)
6378 struct constructor_range_stack *p, *range_stack;
6381 range_stack = constructor_range_stack;
6382 constructor_range_stack = 0;
6383 while (constructor_stack != range_stack->stack)
6385 gcc_assert (constructor_stack->implicit);
6386 process_init_element (pop_init_level (1));
6388 for (p = range_stack;
6389 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6392 gcc_assert (constructor_stack->implicit);
6393 process_init_element (pop_init_level (1));
6396 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6397 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6402 constructor_index = p->index;
6403 constructor_fields = p->fields;
6404 if (finish && p->range_end && p->index == p->range_start)
6412 push_init_level (2);
6413 p->stack = constructor_stack;
6414 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6415 p->index = p->range_start;
6419 constructor_range_stack = range_stack;
6426 constructor_range_stack = 0;
6429 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6430 (guaranteed to be 'volatile' or null) and ARGS (represented using
6431 an ASM_EXPR node). */
6433 build_asm_stmt (tree cv_qualifier, tree args)
6435 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6436 ASM_VOLATILE_P (args) = 1;
6437 return add_stmt (args);
6440 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6441 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6442 SIMPLE indicates whether there was anything at all after the
6443 string in the asm expression -- asm("blah") and asm("blah" : )
6444 are subtly different. We use a ASM_EXPR node to represent this. */
6446 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6452 const char *constraint;
6453 const char **oconstraints;
6454 bool allows_mem, allows_reg, is_inout;
6455 int ninputs, noutputs;
6457 ninputs = list_length (inputs);
6458 noutputs = list_length (outputs);
6459 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6461 string = resolve_asm_operand_names (string, outputs, inputs);
6463 /* Remove output conversions that change the type but not the mode. */
6464 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6466 tree output = TREE_VALUE (tail);
6468 /* ??? Really, this should not be here. Users should be using a
6469 proper lvalue, dammit. But there's a long history of using casts
6470 in the output operands. In cases like longlong.h, this becomes a
6471 primitive form of typechecking -- if the cast can be removed, then
6472 the output operand had a type of the proper width; otherwise we'll
6473 get an error. Gross, but ... */
6474 STRIP_NOPS (output);
6476 if (!lvalue_or_else (output, lv_asm))
6477 output = error_mark_node;
6479 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6480 oconstraints[i] = constraint;
6482 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6483 &allows_mem, &allows_reg, &is_inout))
6485 /* If the operand is going to end up in memory,
6486 mark it addressable. */
6487 if (!allows_reg && !c_mark_addressable (output))
6488 output = error_mark_node;
6491 output = error_mark_node;
6493 TREE_VALUE (tail) = output;
6496 /* Perform default conversions on array and function inputs.
6497 Don't do this for other types as it would screw up operands
6498 expected to be in memory. */
6499 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6503 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6504 input = TREE_VALUE (tail);
6506 input = default_function_array_conversion (input);
6508 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6509 oconstraints, &allows_mem, &allows_reg))
6511 /* If the operand is going to end up in memory,
6512 mark it addressable. */
6513 if (!allows_reg && allows_mem)
6515 /* Strip the nops as we allow this case. FIXME, this really
6516 should be rejected or made deprecated. */
6518 if (!c_mark_addressable (input))
6519 input = error_mark_node;
6523 input = error_mark_node;
6525 TREE_VALUE (tail) = input;
6528 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6530 /* Simple asm statements are treated as volatile. */
6533 ASM_VOLATILE_P (args) = 1;
6534 ASM_INPUT_P (args) = 1;
6540 /* Generate a goto statement to LABEL. */
6543 c_finish_goto_label (tree label)
6545 tree decl = lookup_label (label);
6549 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6551 error ("jump into statement expression");
6555 if (C_DECL_UNJUMPABLE_VM (decl))
6557 error ("jump into scope of identifier with variably modified type");
6561 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6563 /* No jump from outside this statement expression context, so
6564 record that there is a jump from within this context. */
6565 struct c_label_list *nlist;
6566 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6567 nlist->next = label_context_stack_se->labels_used;
6568 nlist->label = decl;
6569 label_context_stack_se->labels_used = nlist;
6572 if (!C_DECL_UNDEFINABLE_VM (decl))
6574 /* No jump from outside this context context of identifiers with
6575 variably modified type, so record that there is a jump from
6576 within this context. */
6577 struct c_label_list *nlist;
6578 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6579 nlist->next = label_context_stack_vm->labels_used;
6580 nlist->label = decl;
6581 label_context_stack_vm->labels_used = nlist;
6584 TREE_USED (decl) = 1;
6585 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6588 /* Generate a computed goto statement to EXPR. */
6591 c_finish_goto_ptr (tree expr)
6594 pedwarn ("ISO C forbids %<goto *expr;%>");
6595 expr = convert (ptr_type_node, expr);
6596 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6599 /* Generate a C `return' statement. RETVAL is the expression for what
6600 to return, or a null pointer for `return;' with no value. */
6603 c_finish_return (tree retval)
6605 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6607 if (TREE_THIS_VOLATILE (current_function_decl))
6608 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6612 current_function_returns_null = 1;
6613 if ((warn_return_type || flag_isoc99)
6614 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6615 pedwarn_c99 ("%<return%> with no value, in "
6616 "function returning non-void");
6618 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6620 current_function_returns_null = 1;
6621 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6622 pedwarn ("%<return%> with a value, in function returning void");
6626 tree t = convert_for_assignment (valtype, retval, ic_return,
6627 NULL_TREE, NULL_TREE, 0);
6628 tree res = DECL_RESULT (current_function_decl);
6631 current_function_returns_value = 1;
6632 if (t == error_mark_node)
6635 inner = t = convert (TREE_TYPE (res), t);
6637 /* Strip any conversions, additions, and subtractions, and see if
6638 we are returning the address of a local variable. Warn if so. */
6641 switch (TREE_CODE (inner))
6643 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6645 inner = TREE_OPERAND (inner, 0);
6649 /* If the second operand of the MINUS_EXPR has a pointer
6650 type (or is converted from it), this may be valid, so
6651 don't give a warning. */
6653 tree op1 = TREE_OPERAND (inner, 1);
6655 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6656 && (TREE_CODE (op1) == NOP_EXPR
6657 || TREE_CODE (op1) == NON_LVALUE_EXPR
6658 || TREE_CODE (op1) == CONVERT_EXPR))
6659 op1 = TREE_OPERAND (op1, 0);
6661 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6664 inner = TREE_OPERAND (inner, 0);
6669 inner = TREE_OPERAND (inner, 0);
6671 while (REFERENCE_CLASS_P (inner)
6672 && TREE_CODE (inner) != INDIRECT_REF)
6673 inner = TREE_OPERAND (inner, 0);
6676 && !DECL_EXTERNAL (inner)
6677 && !TREE_STATIC (inner)
6678 && DECL_CONTEXT (inner) == current_function_decl)
6679 warning (0, "function returns address of local variable");
6689 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6692 return add_stmt (build_stmt (RETURN_EXPR, retval));
6696 /* The SWITCH_EXPR being built. */
6699 /* The original type of the testing expression, i.e. before the
6700 default conversion is applied. */
6703 /* A splay-tree mapping the low element of a case range to the high
6704 element, or NULL_TREE if there is no high element. Used to
6705 determine whether or not a new case label duplicates an old case
6706 label. We need a tree, rather than simply a hash table, because
6707 of the GNU case range extension. */
6710 /* Number of nested statement expressions within this switch
6711 statement; if nonzero, case and default labels may not
6713 unsigned int blocked_stmt_expr;
6715 /* Scope of outermost declarations of identifiers with variably
6716 modified type within this switch statement; if nonzero, case and
6717 default labels may not appear. */
6718 unsigned int blocked_vm;
6720 /* The next node on the stack. */
6721 struct c_switch *next;
6724 /* A stack of the currently active switch statements. The innermost
6725 switch statement is on the top of the stack. There is no need to
6726 mark the stack for garbage collection because it is only active
6727 during the processing of the body of a function, and we never
6728 collect at that point. */
6730 struct c_switch *c_switch_stack;
6732 /* Start a C switch statement, testing expression EXP. Return the new
6736 c_start_case (tree exp)
6738 enum tree_code code;
6739 tree type, orig_type = error_mark_node;
6740 struct c_switch *cs;
6742 if (exp != error_mark_node)
6744 code = TREE_CODE (TREE_TYPE (exp));
6745 orig_type = TREE_TYPE (exp);
6747 if (!INTEGRAL_TYPE_P (orig_type)
6748 && code != ERROR_MARK)
6750 error ("switch quantity not an integer");
6751 exp = integer_zero_node;
6752 orig_type = error_mark_node;
6756 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6758 if (warn_traditional && !in_system_header
6759 && (type == long_integer_type_node
6760 || type == long_unsigned_type_node))
6761 warning (0, "%<long%> switch expression not converted to "
6762 "%<int%> in ISO C");
6764 exp = default_conversion (exp);
6765 type = TREE_TYPE (exp);
6769 /* Add this new SWITCH_EXPR to the stack. */
6770 cs = XNEW (struct c_switch);
6771 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
6772 cs->orig_type = orig_type;
6773 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6774 cs->blocked_stmt_expr = 0;
6776 cs->next = c_switch_stack;
6777 c_switch_stack = cs;
6779 return add_stmt (cs->switch_expr);
6782 /* Process a case label. */
6785 do_case (tree low_value, tree high_value)
6787 tree label = NULL_TREE;
6789 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
6790 && !c_switch_stack->blocked_vm)
6792 label = c_add_case_label (c_switch_stack->cases,
6793 SWITCH_COND (c_switch_stack->switch_expr),
6794 c_switch_stack->orig_type,
6795 low_value, high_value);
6796 if (label == error_mark_node)
6799 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
6802 error ("case label in statement expression not containing "
6803 "enclosing switch statement");
6805 error ("%<default%> label in statement expression not containing "
6806 "enclosing switch statement");
6808 else if (c_switch_stack && c_switch_stack->blocked_vm)
6811 error ("case label in scope of identifier with variably modified "
6812 "type not containing enclosing switch statement");
6814 error ("%<default%> label in scope of identifier with variably "
6815 "modified type not containing enclosing switch statement");
6818 error ("case label not within a switch statement");
6820 error ("%<default%> label not within a switch statement");
6825 /* Finish the switch statement. */
6828 c_finish_case (tree body)
6830 struct c_switch *cs = c_switch_stack;
6831 location_t switch_location;
6833 SWITCH_BODY (cs->switch_expr) = body;
6835 /* We must not be within a statement expression nested in the switch
6836 at this point; we might, however, be within the scope of an
6837 identifier with variably modified type nested in the switch. */
6838 gcc_assert (!cs->blocked_stmt_expr);
6840 /* Emit warnings as needed. */
6841 if (EXPR_HAS_LOCATION (cs->switch_expr))
6842 switch_location = EXPR_LOCATION (cs->switch_expr);
6844 switch_location = input_location;
6845 c_do_switch_warnings (cs->cases, switch_location,
6846 TREE_TYPE (cs->switch_expr),
6847 SWITCH_COND (cs->switch_expr));
6849 /* Pop the stack. */
6850 c_switch_stack = cs->next;
6851 splay_tree_delete (cs->cases);
6855 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6856 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6857 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6858 statement, and was not surrounded with parenthesis. */
6861 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6862 tree else_block, bool nested_if)
6866 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6867 if (warn_parentheses && nested_if && else_block == NULL)
6869 tree inner_if = then_block;
6871 /* We know from the grammar productions that there is an IF nested
6872 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6873 it might not be exactly THEN_BLOCK, but should be the last
6874 non-container statement within. */
6876 switch (TREE_CODE (inner_if))
6881 inner_if = BIND_EXPR_BODY (inner_if);
6883 case STATEMENT_LIST:
6884 inner_if = expr_last (then_block);
6886 case TRY_FINALLY_EXPR:
6887 case TRY_CATCH_EXPR:
6888 inner_if = TREE_OPERAND (inner_if, 0);
6895 if (COND_EXPR_ELSE (inner_if))
6896 warning (0, "%Hsuggest explicit braces to avoid ambiguous %<else%>",
6900 /* Diagnose ";" via the special empty statement node that we create. */
6903 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6906 warning (0, "%Hempty body in an if-statement",
6907 EXPR_LOCUS (then_block));
6908 then_block = alloc_stmt_list ();
6911 && TREE_CODE (else_block) == NOP_EXPR
6912 && !TREE_TYPE (else_block))
6914 warning (0, "%Hempty body in an else-statement",
6915 EXPR_LOCUS (else_block));
6916 else_block = alloc_stmt_list ();
6920 stmt = build3 (COND_EXPR, NULL_TREE, cond, then_block, else_block);
6921 SET_EXPR_LOCATION (stmt, if_locus);
6925 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6926 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6927 is false for DO loops. INCR is the FOR increment expression. BODY is
6928 the statement controlled by the loop. BLAB is the break label. CLAB is
6929 the continue label. Everything is allowed to be NULL. */
6932 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6933 tree blab, tree clab, bool cond_is_first)
6935 tree entry = NULL, exit = NULL, t;
6937 /* If the condition is zero don't generate a loop construct. */
6938 if (cond && integer_zerop (cond))
6942 t = build_and_jump (&blab);
6943 SET_EXPR_LOCATION (t, start_locus);
6949 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6951 /* If we have an exit condition, then we build an IF with gotos either
6952 out of the loop, or to the top of it. If there's no exit condition,
6953 then we just build a jump back to the top. */
6954 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6956 if (cond && !integer_nonzerop (cond))
6958 /* Canonicalize the loop condition to the end. This means
6959 generating a branch to the loop condition. Reuse the
6960 continue label, if possible. */
6965 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6966 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
6969 t = build1 (GOTO_EXPR, void_type_node, clab);
6970 SET_EXPR_LOCATION (t, start_locus);
6974 t = build_and_jump (&blab);
6975 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
6978 SET_EXPR_LOCATION (exit, start_locus);
6980 SET_EXPR_LOCATION (exit, input_location);
6989 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
6997 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7001 c_finish_bc_stmt (tree *label_p, bool is_break)
7004 tree label = *label_p;
7006 /* In switch statements break is sometimes stylistically used after
7007 a return statement. This can lead to spurious warnings about
7008 control reaching the end of a non-void function when it is
7009 inlined. Note that we are calling block_may_fallthru with
7010 language specific tree nodes; this works because
7011 block_may_fallthru returns true when given something it does not
7013 skip = !block_may_fallthru (cur_stmt_list);
7018 *label_p = label = create_artificial_label ();
7020 else if (TREE_CODE (label) != LABEL_DECL)
7023 error ("break statement not within loop or switch");
7025 error ("continue statement not within a loop");
7032 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7035 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7038 emit_side_effect_warnings (tree expr)
7040 if (expr == error_mark_node)
7042 else if (!TREE_SIDE_EFFECTS (expr))
7044 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7045 warning (0, "%Hstatement with no effect",
7046 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7048 else if (warn_unused_value)
7049 warn_if_unused_value (expr, input_location);
7052 /* Process an expression as if it were a complete statement. Emit
7053 diagnostics, but do not call ADD_STMT. */
7056 c_process_expr_stmt (tree expr)
7061 /* Do default conversion if safe and possibly important,
7062 in case within ({...}). */
7063 if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
7064 && (flag_isoc99 || lvalue_p (expr)))
7065 || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
7066 expr = default_conversion (expr);
7068 if (warn_sequence_point)
7069 verify_sequence_points (expr);
7071 if (TREE_TYPE (expr) != error_mark_node
7072 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7073 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7074 error ("expression statement has incomplete type");
7076 /* If we're not processing a statement expression, warn about unused values.
7077 Warnings for statement expressions will be emitted later, once we figure
7078 out which is the result. */
7079 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7080 && (extra_warnings || warn_unused_value))
7081 emit_side_effect_warnings (expr);
7083 /* If the expression is not of a type to which we cannot assign a line
7084 number, wrap the thing in a no-op NOP_EXPR. */
7085 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7086 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7089 SET_EXPR_LOCATION (expr, input_location);
7094 /* Emit an expression as a statement. */
7097 c_finish_expr_stmt (tree expr)
7100 return add_stmt (c_process_expr_stmt (expr));
7105 /* Do the opposite and emit a statement as an expression. To begin,
7106 create a new binding level and return it. */
7109 c_begin_stmt_expr (void)
7112 struct c_label_context_se *nstack;
7113 struct c_label_list *glist;
7115 /* We must force a BLOCK for this level so that, if it is not expanded
7116 later, there is a way to turn off the entire subtree of blocks that
7117 are contained in it. */
7119 ret = c_begin_compound_stmt (true);
7122 c_switch_stack->blocked_stmt_expr++;
7123 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7125 for (glist = label_context_stack_se->labels_used;
7127 glist = glist->next)
7129 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7131 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7132 nstack->labels_def = NULL;
7133 nstack->labels_used = NULL;
7134 nstack->next = label_context_stack_se;
7135 label_context_stack_se = nstack;
7137 /* Mark the current statement list as belonging to a statement list. */
7138 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7144 c_finish_stmt_expr (tree body)
7146 tree last, type, tmp, val;
7148 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7150 body = c_end_compound_stmt (body, true);
7153 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7154 c_switch_stack->blocked_stmt_expr--;
7156 /* It is no longer possible to jump to labels defined within this
7157 statement expression. */
7158 for (dlist = label_context_stack_se->labels_def;
7160 dlist = dlist->next)
7162 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7164 /* It is again possible to define labels with a goto just outside
7165 this statement expression. */
7166 for (glist = label_context_stack_se->next->labels_used;
7168 glist = glist->next)
7170 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7173 if (glist_prev != NULL)
7174 glist_prev->next = label_context_stack_se->labels_used;
7176 label_context_stack_se->next->labels_used
7177 = label_context_stack_se->labels_used;
7178 label_context_stack_se = label_context_stack_se->next;
7180 /* Locate the last statement in BODY. See c_end_compound_stmt
7181 about always returning a BIND_EXPR. */
7182 last_p = &BIND_EXPR_BODY (body);
7183 last = BIND_EXPR_BODY (body);
7186 if (TREE_CODE (last) == STATEMENT_LIST)
7188 tree_stmt_iterator i;
7190 /* This can happen with degenerate cases like ({ }). No value. */
7191 if (!TREE_SIDE_EFFECTS (last))
7194 /* If we're supposed to generate side effects warnings, process
7195 all of the statements except the last. */
7196 if (extra_warnings || warn_unused_value)
7198 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7199 emit_side_effect_warnings (tsi_stmt (i));
7202 i = tsi_last (last);
7203 last_p = tsi_stmt_ptr (i);
7207 /* If the end of the list is exception related, then the list was split
7208 by a call to push_cleanup. Continue searching. */
7209 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7210 || TREE_CODE (last) == TRY_CATCH_EXPR)
7212 last_p = &TREE_OPERAND (last, 0);
7214 goto continue_searching;
7217 /* In the case that the BIND_EXPR is not necessary, return the
7218 expression out from inside it. */
7219 if (last == error_mark_node
7220 || (last == BIND_EXPR_BODY (body)
7221 && BIND_EXPR_VARS (body) == NULL))
7224 /* Extract the type of said expression. */
7225 type = TREE_TYPE (last);
7227 /* If we're not returning a value at all, then the BIND_EXPR that
7228 we already have is a fine expression to return. */
7229 if (!type || VOID_TYPE_P (type))
7232 /* Now that we've located the expression containing the value, it seems
7233 silly to make voidify_wrapper_expr repeat the process. Create a
7234 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7235 tmp = create_tmp_var_raw (type, NULL);
7237 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7238 tree_expr_nonnegative_p giving up immediately. */
7240 if (TREE_CODE (val) == NOP_EXPR
7241 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7242 val = TREE_OPERAND (val, 0);
7244 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7245 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7247 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7250 /* Begin the scope of an identifier of variably modified type, scope
7251 number SCOPE. Jumping from outside this scope to inside it is not
7255 c_begin_vm_scope (unsigned int scope)
7257 struct c_label_context_vm *nstack;
7258 struct c_label_list *glist;
7260 gcc_assert (scope > 0);
7261 if (c_switch_stack && !c_switch_stack->blocked_vm)
7262 c_switch_stack->blocked_vm = scope;
7263 for (glist = label_context_stack_vm->labels_used;
7265 glist = glist->next)
7267 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7269 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7270 nstack->labels_def = NULL;
7271 nstack->labels_used = NULL;
7272 nstack->scope = scope;
7273 nstack->next = label_context_stack_vm;
7274 label_context_stack_vm = nstack;
7277 /* End a scope which may contain identifiers of variably modified
7278 type, scope number SCOPE. */
7281 c_end_vm_scope (unsigned int scope)
7283 if (label_context_stack_vm == NULL)
7285 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7286 c_switch_stack->blocked_vm = 0;
7287 /* We may have a number of nested scopes of identifiers with
7288 variably modified type, all at this depth. Pop each in turn. */
7289 while (label_context_stack_vm->scope == scope)
7291 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7293 /* It is no longer possible to jump to labels defined within this
7295 for (dlist = label_context_stack_vm->labels_def;
7297 dlist = dlist->next)
7299 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7301 /* It is again possible to define labels with a goto just outside
7303 for (glist = label_context_stack_vm->next->labels_used;
7305 glist = glist->next)
7307 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7310 if (glist_prev != NULL)
7311 glist_prev->next = label_context_stack_vm->labels_used;
7313 label_context_stack_vm->next->labels_used
7314 = label_context_stack_vm->labels_used;
7315 label_context_stack_vm = label_context_stack_vm->next;
7319 /* Begin and end compound statements. This is as simple as pushing
7320 and popping new statement lists from the tree. */
7323 c_begin_compound_stmt (bool do_scope)
7325 tree stmt = push_stmt_list ();
7332 c_end_compound_stmt (tree stmt, bool do_scope)
7338 if (c_dialect_objc ())
7339 objc_clear_super_receiver ();
7340 block = pop_scope ();
7343 stmt = pop_stmt_list (stmt);
7344 stmt = c_build_bind_expr (block, stmt);
7346 /* If this compound statement is nested immediately inside a statement
7347 expression, then force a BIND_EXPR to be created. Otherwise we'll
7348 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7349 STATEMENT_LISTs merge, and thus we can lose track of what statement
7352 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7353 && TREE_CODE (stmt) != BIND_EXPR)
7355 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7356 TREE_SIDE_EFFECTS (stmt) = 1;
7362 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7363 when the current scope is exited. EH_ONLY is true when this is not
7364 meant to apply to normal control flow transfer. */
7367 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7369 enum tree_code code;
7373 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7374 stmt = build_stmt (code, NULL, cleanup);
7376 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7377 list = push_stmt_list ();
7378 TREE_OPERAND (stmt, 0) = list;
7379 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7382 /* Build a binary-operation expression without default conversions.
7383 CODE is the kind of expression to build.
7384 This function differs from `build' in several ways:
7385 the data type of the result is computed and recorded in it,
7386 warnings are generated if arg data types are invalid,
7387 special handling for addition and subtraction of pointers is known,
7388 and some optimization is done (operations on narrow ints
7389 are done in the narrower type when that gives the same result).
7390 Constant folding is also done before the result is returned.
7392 Note that the operands will never have enumeral types, or function
7393 or array types, because either they will have the default conversions
7394 performed or they have both just been converted to some other type in which
7395 the arithmetic is to be done. */
7398 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7402 enum tree_code code0, code1;
7405 /* Expression code to give to the expression when it is built.
7406 Normally this is CODE, which is what the caller asked for,
7407 but in some special cases we change it. */
7408 enum tree_code resultcode = code;
7410 /* Data type in which the computation is to be performed.
7411 In the simplest cases this is the common type of the arguments. */
7412 tree result_type = NULL;
7414 /* Nonzero means operands have already been type-converted
7415 in whatever way is necessary.
7416 Zero means they need to be converted to RESULT_TYPE. */
7419 /* Nonzero means create the expression with this type, rather than
7421 tree build_type = 0;
7423 /* Nonzero means after finally constructing the expression
7424 convert it to this type. */
7425 tree final_type = 0;
7427 /* Nonzero if this is an operation like MIN or MAX which can
7428 safely be computed in short if both args are promoted shorts.
7429 Also implies COMMON.
7430 -1 indicates a bitwise operation; this makes a difference
7431 in the exact conditions for when it is safe to do the operation
7432 in a narrower mode. */
7435 /* Nonzero if this is a comparison operation;
7436 if both args are promoted shorts, compare the original shorts.
7437 Also implies COMMON. */
7438 int short_compare = 0;
7440 /* Nonzero if this is a right-shift operation, which can be computed on the
7441 original short and then promoted if the operand is a promoted short. */
7442 int short_shift = 0;
7444 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7449 op0 = default_conversion (orig_op0);
7450 op1 = default_conversion (orig_op1);
7458 type0 = TREE_TYPE (op0);
7459 type1 = TREE_TYPE (op1);
7461 /* The expression codes of the data types of the arguments tell us
7462 whether the arguments are integers, floating, pointers, etc. */
7463 code0 = TREE_CODE (type0);
7464 code1 = TREE_CODE (type1);
7466 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7467 STRIP_TYPE_NOPS (op0);
7468 STRIP_TYPE_NOPS (op1);
7470 /* If an error was already reported for one of the arguments,
7471 avoid reporting another error. */
7473 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7474 return error_mark_node;
7479 /* Handle the pointer + int case. */
7480 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7481 return pointer_int_sum (PLUS_EXPR, op0, op1);
7482 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7483 return pointer_int_sum (PLUS_EXPR, op1, op0);
7489 /* Subtraction of two similar pointers.
7490 We must subtract them as integers, then divide by object size. */
7491 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7492 && comp_target_types (type0, type1, 1))
7493 return pointer_diff (op0, op1);
7494 /* Handle pointer minus int. Just like pointer plus int. */
7495 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7496 return pointer_int_sum (MINUS_EXPR, op0, op1);
7505 case TRUNC_DIV_EXPR:
7507 case FLOOR_DIV_EXPR:
7508 case ROUND_DIV_EXPR:
7509 case EXACT_DIV_EXPR:
7510 /* Floating point division by zero is a legitimate way to obtain
7511 infinities and NaNs. */
7512 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7513 warning (0, "division by zero");
7515 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7516 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7517 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7518 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7520 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7521 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7522 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7523 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7525 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
7526 resultcode = RDIV_EXPR;
7528 /* Although it would be tempting to shorten always here, that
7529 loses on some targets, since the modulo instruction is
7530 undefined if the quotient can't be represented in the
7531 computation mode. We shorten only if unsigned or if
7532 dividing by something we know != -1. */
7533 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7534 || (TREE_CODE (op1) == INTEGER_CST
7535 && !integer_all_onesp (op1)));
7543 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7545 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7549 case TRUNC_MOD_EXPR:
7550 case FLOOR_MOD_EXPR:
7551 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
7552 warning (0, "division by zero");
7554 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7556 /* Although it would be tempting to shorten always here, that loses
7557 on some targets, since the modulo instruction is undefined if the
7558 quotient can't be represented in the computation mode. We shorten
7559 only if unsigned or if dividing by something we know != -1. */
7560 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7561 || (TREE_CODE (op1) == INTEGER_CST
7562 && !integer_all_onesp (op1)));
7567 case TRUTH_ANDIF_EXPR:
7568 case TRUTH_ORIF_EXPR:
7569 case TRUTH_AND_EXPR:
7571 case TRUTH_XOR_EXPR:
7572 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7573 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7574 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7575 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7577 /* Result of these operations is always an int,
7578 but that does not mean the operands should be
7579 converted to ints! */
7580 result_type = integer_type_node;
7581 op0 = c_common_truthvalue_conversion (op0);
7582 op1 = c_common_truthvalue_conversion (op1);
7587 /* Shift operations: result has same type as first operand;
7588 always convert second operand to int.
7589 Also set SHORT_SHIFT if shifting rightward. */
7592 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7594 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7596 if (tree_int_cst_sgn (op1) < 0)
7597 warning (0, "right shift count is negative");
7600 if (!integer_zerop (op1))
7603 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7604 warning (0, "right shift count >= width of type");
7608 /* Use the type of the value to be shifted. */
7609 result_type = type0;
7610 /* Convert the shift-count to an integer, regardless of size
7611 of value being shifted. */
7612 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7613 op1 = convert (integer_type_node, op1);
7614 /* Avoid converting op1 to result_type later. */
7620 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7622 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7624 if (tree_int_cst_sgn (op1) < 0)
7625 warning (0, "left shift count is negative");
7627 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7628 warning (0, "left shift count >= width of type");
7631 /* Use the type of the value to be shifted. */
7632 result_type = type0;
7633 /* Convert the shift-count to an integer, regardless of size
7634 of value being shifted. */
7635 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7636 op1 = convert (integer_type_node, op1);
7637 /* Avoid converting op1 to result_type later. */
7644 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
7645 warning (0, "comparing floating point with == or != is unsafe");
7646 /* Result of comparison is always int,
7647 but don't convert the args to int! */
7648 build_type = integer_type_node;
7649 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7650 || code0 == COMPLEX_TYPE)
7651 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7652 || code1 == COMPLEX_TYPE))
7654 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7656 tree tt0 = TREE_TYPE (type0);
7657 tree tt1 = TREE_TYPE (type1);
7658 /* Anything compares with void *. void * compares with anything.
7659 Otherwise, the targets must be compatible
7660 and both must be object or both incomplete. */
7661 if (comp_target_types (type0, type1, 1))
7662 result_type = common_pointer_type (type0, type1);
7663 else if (VOID_TYPE_P (tt0))
7665 /* op0 != orig_op0 detects the case of something
7666 whose value is 0 but which isn't a valid null ptr const. */
7667 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7668 && TREE_CODE (tt1) == FUNCTION_TYPE)
7669 pedwarn ("ISO C forbids comparison of %<void *%>"
7670 " with function pointer");
7672 else if (VOID_TYPE_P (tt1))
7674 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7675 && TREE_CODE (tt0) == FUNCTION_TYPE)
7676 pedwarn ("ISO C forbids comparison of %<void *%>"
7677 " with function pointer");
7680 pedwarn ("comparison of distinct pointer types lacks a cast");
7682 if (result_type == NULL_TREE)
7683 result_type = ptr_type_node;
7685 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7686 && integer_zerop (op1))
7687 result_type = type0;
7688 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7689 && integer_zerop (op0))
7690 result_type = type1;
7691 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7693 result_type = type0;
7694 pedwarn ("comparison between pointer and integer");
7696 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7698 result_type = type1;
7699 pedwarn ("comparison between pointer and integer");
7707 build_type = integer_type_node;
7708 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7709 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7711 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7713 if (comp_target_types (type0, type1, 1))
7715 result_type = common_pointer_type (type0, type1);
7716 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7717 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7718 pedwarn ("comparison of complete and incomplete pointers");
7720 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7721 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7725 result_type = ptr_type_node;
7726 pedwarn ("comparison of distinct pointer types lacks a cast");
7729 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7730 && integer_zerop (op1))
7732 result_type = type0;
7733 if (pedantic || extra_warnings)
7734 pedwarn ("ordered comparison of pointer with integer zero");
7736 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7737 && integer_zerop (op0))
7739 result_type = type1;
7741 pedwarn ("ordered comparison of pointer with integer zero");
7743 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7745 result_type = type0;
7746 pedwarn ("comparison between pointer and integer");
7748 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7750 result_type = type1;
7751 pedwarn ("comparison between pointer and integer");
7759 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7760 return error_mark_node;
7762 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7763 || code0 == VECTOR_TYPE)
7765 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7766 || code1 == VECTOR_TYPE))
7768 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7770 if (shorten || common || short_compare)
7771 result_type = c_common_type (type0, type1);
7773 /* For certain operations (which identify themselves by shorten != 0)
7774 if both args were extended from the same smaller type,
7775 do the arithmetic in that type and then extend.
7777 shorten !=0 and !=1 indicates a bitwise operation.
7778 For them, this optimization is safe only if
7779 both args are zero-extended or both are sign-extended.
7780 Otherwise, we might change the result.
7781 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7782 but calculated in (unsigned short) it would be (unsigned short)-1. */
7784 if (shorten && none_complex)
7786 int unsigned0, unsigned1;
7787 tree arg0 = get_narrower (op0, &unsigned0);
7788 tree arg1 = get_narrower (op1, &unsigned1);
7789 /* UNS is 1 if the operation to be done is an unsigned one. */
7790 int uns = TYPE_UNSIGNED (result_type);
7793 final_type = result_type;
7795 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7796 but it *requires* conversion to FINAL_TYPE. */
7798 if ((TYPE_PRECISION (TREE_TYPE (op0))
7799 == TYPE_PRECISION (TREE_TYPE (arg0)))
7800 && TREE_TYPE (op0) != final_type)
7801 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7802 if ((TYPE_PRECISION (TREE_TYPE (op1))
7803 == TYPE_PRECISION (TREE_TYPE (arg1)))
7804 && TREE_TYPE (op1) != final_type)
7805 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7807 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7809 /* For bitwise operations, signedness of nominal type
7810 does not matter. Consider only how operands were extended. */
7814 /* Note that in all three cases below we refrain from optimizing
7815 an unsigned operation on sign-extended args.
7816 That would not be valid. */
7818 /* Both args variable: if both extended in same way
7819 from same width, do it in that width.
7820 Do it unsigned if args were zero-extended. */
7821 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7822 < TYPE_PRECISION (result_type))
7823 && (TYPE_PRECISION (TREE_TYPE (arg1))
7824 == TYPE_PRECISION (TREE_TYPE (arg0)))
7825 && unsigned0 == unsigned1
7826 && (unsigned0 || !uns))
7828 = c_common_signed_or_unsigned_type
7829 (unsigned0, c_common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7830 else if (TREE_CODE (arg0) == INTEGER_CST
7831 && (unsigned1 || !uns)
7832 && (TYPE_PRECISION (TREE_TYPE (arg1))
7833 < TYPE_PRECISION (result_type))
7835 = c_common_signed_or_unsigned_type (unsigned1,
7837 int_fits_type_p (arg0, type)))
7839 else if (TREE_CODE (arg1) == INTEGER_CST
7840 && (unsigned0 || !uns)
7841 && (TYPE_PRECISION (TREE_TYPE (arg0))
7842 < TYPE_PRECISION (result_type))
7844 = c_common_signed_or_unsigned_type (unsigned0,
7846 int_fits_type_p (arg1, type)))
7850 /* Shifts can be shortened if shifting right. */
7855 tree arg0 = get_narrower (op0, &unsigned_arg);
7857 final_type = result_type;
7859 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7860 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7862 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7863 /* We can shorten only if the shift count is less than the
7864 number of bits in the smaller type size. */
7865 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7866 /* We cannot drop an unsigned shift after sign-extension. */
7867 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7869 /* Do an unsigned shift if the operand was zero-extended. */
7871 = c_common_signed_or_unsigned_type (unsigned_arg,
7873 /* Convert value-to-be-shifted to that type. */
7874 if (TREE_TYPE (op0) != result_type)
7875 op0 = convert (result_type, op0);
7880 /* Comparison operations are shortened too but differently.
7881 They identify themselves by setting short_compare = 1. */
7885 /* Don't write &op0, etc., because that would prevent op0
7886 from being kept in a register.
7887 Instead, make copies of the our local variables and
7888 pass the copies by reference, then copy them back afterward. */
7889 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7890 enum tree_code xresultcode = resultcode;
7892 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7897 op0 = xop0, op1 = xop1;
7899 resultcode = xresultcode;
7901 if (warn_sign_compare && skip_evaluation == 0)
7903 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7904 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7905 int unsignedp0, unsignedp1;
7906 tree primop0 = get_narrower (op0, &unsignedp0);
7907 tree primop1 = get_narrower (op1, &unsignedp1);
7911 STRIP_TYPE_NOPS (xop0);
7912 STRIP_TYPE_NOPS (xop1);
7914 /* Give warnings for comparisons between signed and unsigned
7915 quantities that may fail.
7917 Do the checking based on the original operand trees, so that
7918 casts will be considered, but default promotions won't be.
7920 Do not warn if the comparison is being done in a signed type,
7921 since the signed type will only be chosen if it can represent
7922 all the values of the unsigned type. */
7923 if (!TYPE_UNSIGNED (result_type))
7925 /* Do not warn if both operands are the same signedness. */
7926 else if (op0_signed == op1_signed)
7933 sop = xop0, uop = xop1;
7935 sop = xop1, uop = xop0;
7937 /* Do not warn if the signed quantity is an
7938 unsuffixed integer literal (or some static
7939 constant expression involving such literals or a
7940 conditional expression involving such literals)
7941 and it is non-negative. */
7942 if (tree_expr_nonnegative_p (sop))
7944 /* Do not warn if the comparison is an equality operation,
7945 the unsigned quantity is an integral constant, and it
7946 would fit in the result if the result were signed. */
7947 else if (TREE_CODE (uop) == INTEGER_CST
7948 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
7950 (uop, c_common_signed_type (result_type)))
7952 /* Do not warn if the unsigned quantity is an enumeration
7953 constant and its maximum value would fit in the result
7954 if the result were signed. */
7955 else if (TREE_CODE (uop) == INTEGER_CST
7956 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
7958 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
7959 c_common_signed_type (result_type)))
7962 warning (0, "comparison between signed and unsigned");
7965 /* Warn if two unsigned values are being compared in a size
7966 larger than their original size, and one (and only one) is the
7967 result of a `~' operator. This comparison will always fail.
7969 Also warn if one operand is a constant, and the constant
7970 does not have all bits set that are set in the ~ operand
7971 when it is extended. */
7973 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
7974 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
7976 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
7977 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
7980 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
7983 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
7986 HOST_WIDE_INT constant, mask;
7987 int unsignedp, bits;
7989 if (host_integerp (primop0, 0))
7992 unsignedp = unsignedp1;
7993 constant = tree_low_cst (primop0, 0);
7998 unsignedp = unsignedp0;
7999 constant = tree_low_cst (primop1, 0);
8002 bits = TYPE_PRECISION (TREE_TYPE (primop));
8003 if (bits < TYPE_PRECISION (result_type)
8004 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8006 mask = (~(HOST_WIDE_INT) 0) << bits;
8007 if ((mask & constant) != mask)
8008 warning (0, "comparison of promoted ~unsigned with constant");
8011 else if (unsignedp0 && unsignedp1
8012 && (TYPE_PRECISION (TREE_TYPE (primop0))
8013 < TYPE_PRECISION (result_type))
8014 && (TYPE_PRECISION (TREE_TYPE (primop1))
8015 < TYPE_PRECISION (result_type)))
8016 warning (0, "comparison of promoted ~unsigned with unsigned");
8022 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8023 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8024 Then the expression will be built.
8025 It will be given type FINAL_TYPE if that is nonzero;
8026 otherwise, it will be given type RESULT_TYPE. */
8030 binary_op_error (code);
8031 return error_mark_node;
8036 if (TREE_TYPE (op0) != result_type)
8037 op0 = convert (result_type, op0);
8038 if (TREE_TYPE (op1) != result_type)
8039 op1 = convert (result_type, op1);
8041 /* This can happen if one operand has a vector type, and the other
8042 has a different type. */
8043 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8044 return error_mark_node;
8047 if (build_type == NULL_TREE)
8048 build_type = result_type;
8051 tree result = build2 (resultcode, build_type, op0, op1);
8053 /* Treat expressions in initializers specially as they can't trap. */
8054 result = require_constant_value ? fold_initializer (result)
8057 if (final_type != 0)
8058 result = convert (final_type, result);
8064 /* Convert EXPR to be a truth-value, validating its type for this
8065 purpose. Passes EXPR to default_function_array_conversion. */
8068 c_objc_common_truthvalue_conversion (tree expr)
8070 expr = default_function_array_conversion (expr);
8071 switch (TREE_CODE (TREE_TYPE (expr)))
8074 error ("used array that cannot be converted to pointer where scalar is required");
8075 return error_mark_node;
8078 error ("used struct type value where scalar is required");
8079 return error_mark_node;
8082 error ("used union type value where scalar is required");
8083 return error_mark_node;
8089 /* ??? Should we also give an error for void and vectors rather than
8090 leaving those to give errors later? */
8091 return c_common_truthvalue_conversion (expr);