1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 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.
28 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
29 and to process initializations in declarations (since they work
30 like a strange sort of assignment). */
34 #include "coretypes.h"
38 #include "langhooks.h"
49 /* Nonzero if we've already printed a "missing braces around initializer"
50 message within this initializer. */
51 static int missing_braces_mentioned;
53 static int require_constant_value;
54 static int require_constant_elements;
56 static tree qualify_type (tree, tree);
57 static int tagged_types_tu_compatible_p (tree, tree, int);
58 static int comp_target_types (tree, tree, int);
59 static int function_types_compatible_p (tree, tree, int);
60 static int type_lists_compatible_p (tree, tree, int);
61 static tree decl_constant_value_for_broken_optimization (tree);
62 static tree default_function_array_conversion (tree);
63 static tree lookup_field (tree, tree);
64 static tree convert_arguments (tree, tree, tree, tree);
65 static tree pointer_diff (tree, tree);
66 static tree internal_build_compound_expr (tree, int);
67 static tree convert_for_assignment (tree, tree, const char *, tree, tree,
69 static void warn_for_assignment (const char *, const char *, tree, int);
70 static tree valid_compound_expr_initializer (tree, tree);
71 static void push_string (const char *);
72 static void push_member_name (tree);
73 static void push_array_bounds (int);
74 static int spelling_length (void);
75 static char *print_spelling (char *);
76 static void warning_init (const char *);
77 static tree digest_init (tree, tree, int);
78 static void output_init_element (tree, tree, tree, int);
79 static void output_pending_init_elements (int);
80 static int set_designator (int);
81 static void push_range_stack (tree);
82 static void add_pending_init (tree, tree);
83 static void set_nonincremental_init (void);
84 static void set_nonincremental_init_from_string (tree);
85 static tree find_init_member (tree);
86 static int lvalue_or_else (tree, const char *);
88 /* Do `exp = require_complete_type (exp);' to make sure exp
89 does not have an incomplete type. (That includes void types.) */
92 require_complete_type (tree value)
94 tree type = TREE_TYPE (value);
96 if (value == error_mark_node || type == error_mark_node)
97 return error_mark_node;
99 /* First, detect a valid value with a complete type. */
100 if (COMPLETE_TYPE_P (type))
103 c_incomplete_type_error (value, type);
104 return error_mark_node;
107 /* Print an error message for invalid use of an incomplete type.
108 VALUE is the expression that was used (or 0 if that isn't known)
109 and TYPE is the type that was invalid. */
112 c_incomplete_type_error (tree value, tree type)
114 const char *type_code_string;
116 /* Avoid duplicate error message. */
117 if (TREE_CODE (type) == ERROR_MARK)
120 if (value != 0 && (TREE_CODE (value) == VAR_DECL
121 || TREE_CODE (value) == PARM_DECL))
122 error ("`%s' has an incomplete type",
123 IDENTIFIER_POINTER (DECL_NAME (value)));
127 /* We must print an error message. Be clever about what it says. */
129 switch (TREE_CODE (type))
132 type_code_string = "struct";
136 type_code_string = "union";
140 type_code_string = "enum";
144 error ("invalid use of void expression");
148 if (TYPE_DOMAIN (type))
150 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
152 error ("invalid use of flexible array member");
155 type = TREE_TYPE (type);
158 error ("invalid use of array with unspecified bounds");
165 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
166 error ("invalid use of undefined type `%s %s'",
167 type_code_string, IDENTIFIER_POINTER (TYPE_NAME (type)));
169 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
170 error ("invalid use of incomplete typedef `%s'",
171 IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type))));
175 /* Given a type, apply default promotions wrt unnamed function
176 arguments and return the new type. */
179 c_type_promotes_to (tree type)
181 if (TYPE_MAIN_VARIANT (type) == float_type_node)
182 return double_type_node;
184 if (c_promoting_integer_type_p (type))
186 /* Preserve unsignedness if not really getting any wider. */
187 if (TYPE_UNSIGNED (type)
188 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
189 return unsigned_type_node;
190 return integer_type_node;
196 /* Return a variant of TYPE which has all the type qualifiers of LIKE
197 as well as those of TYPE. */
200 qualify_type (tree type, tree like)
202 return c_build_qualified_type (type,
203 TYPE_QUALS (type) | TYPE_QUALS (like));
206 /* Return the composite type of two compatible types.
208 We assume that comptypes has already been done and returned
209 nonzero; if that isn't so, this may crash. In particular, we
210 assume that qualifiers match. */
213 composite_type (tree t1, tree t2)
215 enum tree_code code1;
216 enum tree_code code2;
219 /* Save time if the two types are the same. */
221 if (t1 == t2) return t1;
223 /* If one type is nonsense, use the other. */
224 if (t1 == error_mark_node)
226 if (t2 == error_mark_node)
229 code1 = TREE_CODE (t1);
230 code2 = TREE_CODE (t2);
232 /* Merge the attributes. */
233 attributes = targetm.merge_type_attributes (t1, t2);
235 /* If one is an enumerated type and the other is the compatible
236 integer type, the composite type might be either of the two
237 (DR#013 question 3). For consistency, use the enumerated type as
238 the composite type. */
240 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
242 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
251 /* For two pointers, do this recursively on the target type. */
253 tree pointed_to_1 = TREE_TYPE (t1);
254 tree pointed_to_2 = TREE_TYPE (t2);
255 tree target = composite_type (pointed_to_1, pointed_to_2);
256 t1 = build_pointer_type (target);
257 return build_type_attribute_variant (t1, attributes);
262 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
263 /* Save space: see if the result is identical to one of the args. */
264 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
265 return build_type_attribute_variant (t1, attributes);
266 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
267 return build_type_attribute_variant (t2, attributes);
268 /* Merge the element types, and have a size if either arg has one. */
269 t1 = build_array_type (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
270 return build_type_attribute_variant (t1, attributes);
274 /* Function types: prefer the one that specified arg types.
275 If both do, merge the arg types. Also merge the return types. */
277 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
278 tree p1 = TYPE_ARG_TYPES (t1);
279 tree p2 = TYPE_ARG_TYPES (t2);
284 /* Save space: see if the result is identical to one of the args. */
285 if (valtype == TREE_TYPE (t1) && ! TYPE_ARG_TYPES (t2))
286 return build_type_attribute_variant (t1, attributes);
287 if (valtype == TREE_TYPE (t2) && ! TYPE_ARG_TYPES (t1))
288 return build_type_attribute_variant (t2, attributes);
290 /* Simple way if one arg fails to specify argument types. */
291 if (TYPE_ARG_TYPES (t1) == 0)
293 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
294 return build_type_attribute_variant (t1, attributes);
296 if (TYPE_ARG_TYPES (t2) == 0)
298 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
299 return build_type_attribute_variant (t1, attributes);
302 /* If both args specify argument types, we must merge the two
303 lists, argument by argument. */
304 /* Tell global_bindings_p to return false so that variable_size
305 doesn't abort on VLAs in parameter types. */
306 c_override_global_bindings_to_false = true;
308 len = list_length (p1);
311 for (i = 0; i < len; i++)
312 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
317 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
319 /* A null type means arg type is not specified.
320 Take whatever the other function type has. */
321 if (TREE_VALUE (p1) == 0)
323 TREE_VALUE (n) = TREE_VALUE (p2);
326 if (TREE_VALUE (p2) == 0)
328 TREE_VALUE (n) = TREE_VALUE (p1);
332 /* Given wait (union {union wait *u; int *i} *)
333 and wait (union wait *),
334 prefer union wait * as type of parm. */
335 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
336 && TREE_VALUE (p1) != TREE_VALUE (p2))
339 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
340 memb; memb = TREE_CHAIN (memb))
341 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p2),
344 TREE_VALUE (n) = TREE_VALUE (p2);
346 pedwarn ("function types not truly compatible in ISO C");
350 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
351 && TREE_VALUE (p2) != TREE_VALUE (p1))
354 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
355 memb; memb = TREE_CHAIN (memb))
356 if (comptypes (TREE_TYPE (memb), TREE_VALUE (p1),
359 TREE_VALUE (n) = TREE_VALUE (p1);
361 pedwarn ("function types not truly compatible in ISO C");
365 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
369 c_override_global_bindings_to_false = false;
370 t1 = build_function_type (valtype, newargs);
371 /* ... falls through ... */
375 return build_type_attribute_variant (t1, attributes);
380 /* Return the type of a conditional expression between pointers to
381 possibly differently qualified versions of compatible types.
383 We assume that comp_target_types has already been done and returned
384 nonzero; if that isn't so, this may crash. */
387 common_pointer_type (tree t1, tree t2)
394 /* Save time if the two types are the same. */
396 if (t1 == t2) return t1;
398 /* If one type is nonsense, use the other. */
399 if (t1 == error_mark_node)
401 if (t2 == error_mark_node)
404 if (TREE_CODE (t1) != POINTER_TYPE || TREE_CODE (t2) != POINTER_TYPE)
407 /* Merge the attributes. */
408 attributes = targetm.merge_type_attributes (t1, t2);
410 /* Find the composite type of the target types, and combine the
411 qualifiers of the two types' targets. */
412 pointed_to_1 = TREE_TYPE (t1);
413 pointed_to_2 = TREE_TYPE (t2);
414 target = composite_type (TYPE_MAIN_VARIANT (pointed_to_1),
415 TYPE_MAIN_VARIANT (pointed_to_2));
416 t1 = build_pointer_type (c_build_qualified_type
418 TYPE_QUALS (pointed_to_1) |
419 TYPE_QUALS (pointed_to_2)));
420 return build_type_attribute_variant (t1, attributes);
423 /* Return the common type for two arithmetic types under the usual
424 arithmetic conversions. The default conversions have already been
425 applied, and enumerated types converted to their compatible integer
426 types. The resulting type is unqualified and has no attributes.
428 This is the type for the result of most arithmetic operations
429 if the operands have the given two types. */
432 common_type (tree t1, tree t2)
434 enum tree_code code1;
435 enum tree_code code2;
437 /* If one type is nonsense, use the other. */
438 if (t1 == error_mark_node)
440 if (t2 == error_mark_node)
443 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
444 t1 = TYPE_MAIN_VARIANT (t1);
446 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
447 t2 = TYPE_MAIN_VARIANT (t2);
449 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
450 t1 = build_type_attribute_variant (t1, NULL_TREE);
452 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
453 t2 = build_type_attribute_variant (t2, NULL_TREE);
455 /* Save time if the two types are the same. */
457 if (t1 == t2) return t1;
459 code1 = TREE_CODE (t1);
460 code2 = TREE_CODE (t2);
462 if (code1 != VECTOR_TYPE && code1 != COMPLEX_TYPE
463 && code1 != REAL_TYPE && code1 != INTEGER_TYPE)
466 if (code2 != VECTOR_TYPE && code2 != COMPLEX_TYPE
467 && code2 != REAL_TYPE && code2 != INTEGER_TYPE)
470 /* If one type is a vector type, return that type. (How the usual
471 arithmetic conversions apply to the vector types extension is not
472 precisely specified.) */
473 if (code1 == VECTOR_TYPE)
476 if (code2 == VECTOR_TYPE)
479 /* If one type is complex, form the common type of the non-complex
480 components, then make that complex. Use T1 or T2 if it is the
482 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
484 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
485 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
486 tree subtype = common_type (subtype1, subtype2);
488 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
490 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
493 return build_complex_type (subtype);
496 /* If only one is real, use it as the result. */
498 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
501 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
504 /* Both real or both integers; use the one with greater precision. */
506 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
508 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
511 /* Same precision. Prefer long longs to longs to ints when the
512 same precision, following the C99 rules on integer type rank
513 (which are equivalent to the C90 rules for C90 types). */
515 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
516 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
517 return long_long_unsigned_type_node;
519 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
520 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
522 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
523 return long_long_unsigned_type_node;
525 return long_long_integer_type_node;
528 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
529 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
530 return long_unsigned_type_node;
532 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
533 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
535 /* But preserve unsignedness from the other type,
536 since long cannot hold all the values of an unsigned int. */
537 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
538 return long_unsigned_type_node;
540 return long_integer_type_node;
543 /* Likewise, prefer long double to double even if same size. */
544 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
545 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
546 return long_double_type_node;
548 /* Otherwise prefer the unsigned one. */
550 if (TYPE_UNSIGNED (t1))
556 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
557 or various other operations. Return 2 if they are compatible
558 but a warning may be needed if you use them together. */
561 comptypes (tree type1, tree type2, int flags)
567 /* Suppress errors caused by previously reported errors. */
569 if (t1 == t2 || !t1 || !t2
570 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
573 /* If either type is the internal version of sizetype, return the
575 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
576 && TYPE_ORIG_SIZE_TYPE (t1))
577 t1 = TYPE_ORIG_SIZE_TYPE (t1);
579 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
580 && TYPE_ORIG_SIZE_TYPE (t2))
581 t2 = TYPE_ORIG_SIZE_TYPE (t2);
584 /* Enumerated types are compatible with integer types, but this is
585 not transitive: two enumerated types in the same translation unit
586 are compatible with each other only if they are the same type. */
588 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
589 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
590 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
591 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
596 /* Different classes of types can't be compatible. */
598 if (TREE_CODE (t1) != TREE_CODE (t2))
601 /* Qualifiers must match. */
603 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
606 /* Allow for two different type nodes which have essentially the same
607 definition. Note that we already checked for equality of the type
608 qualifiers (just above). */
610 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
613 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
614 if (! (attrval = targetm.comp_type_attributes (t1, t2)))
617 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
620 switch (TREE_CODE (t1))
623 /* We must give ObjC the first crack at comparing pointers, since
624 protocol qualifiers may be involved. */
625 if (c_dialect_objc () && (val = objc_comptypes (t1, t2, 0)) >= 0)
627 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
628 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2), flags));
632 val = function_types_compatible_p (t1, t2, flags);
637 tree d1 = TYPE_DOMAIN (t1);
638 tree d2 = TYPE_DOMAIN (t2);
639 bool d1_variable, d2_variable;
640 bool d1_zero, d2_zero;
643 /* Target types must match incl. qualifiers. */
644 if (TREE_TYPE (t1) != TREE_TYPE (t2)
645 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2),
649 /* Sizes must match unless one is missing or variable. */
650 if (d1 == 0 || d2 == 0 || d1 == d2)
653 d1_zero = ! TYPE_MAX_VALUE (d1);
654 d2_zero = ! TYPE_MAX_VALUE (d2);
656 d1_variable = (! d1_zero
657 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
658 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
659 d2_variable = (! d2_zero
660 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
661 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
663 if (d1_variable || d2_variable)
665 if (d1_zero && d2_zero)
667 if (d1_zero || d2_zero
668 || ! tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
669 || ! tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
676 /* We are dealing with two distinct structs. In assorted Objective-C
677 corner cases, however, these can still be deemed equivalent. */
678 if (c_dialect_objc () && objc_comptypes (t1, t2, 0) == 1)
683 if (val != 1 && !same_translation_unit_p (t1, t2))
684 val = tagged_types_tu_compatible_p (t1, t2, flags);
688 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
689 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2), 0);
695 return attrval == 2 && val == 1 ? 2 : val;
698 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
699 ignoring their qualifiers. REFLEXIVE is only used by ObjC - set it
700 to 1 or 0 depending if the check of the pointer types is meant to
701 be reflexive or not (typically, assignments are not reflexive,
702 while comparisons are reflexive).
706 comp_target_types (tree ttl, tree ttr, int reflexive)
710 /* Give objc_comptypes a crack at letting these types through. */
711 if ((val = objc_comptypes (ttl, ttr, reflexive)) >= 0)
714 val = comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (ttl)),
715 TYPE_MAIN_VARIANT (TREE_TYPE (ttr)), COMPARE_STRICT);
717 if (val == 2 && pedantic)
718 pedwarn ("types are not quite compatible");
722 /* Subroutines of `comptypes'. */
724 /* Determine whether two trees derive from the same translation unit.
725 If the CONTEXT chain ends in a null, that tree's context is still
726 being parsed, so if two trees have context chains ending in null,
727 they're in the same translation unit. */
729 same_translation_unit_p (tree t1, tree t2)
731 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
732 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
734 case 'd': t1 = DECL_CONTEXT (t1); break;
735 case 't': t1 = TYPE_CONTEXT (t1); break;
736 case 'x': t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
740 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
741 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
743 case 'd': t2 = DECL_CONTEXT (t2); break;
744 case 't': t2 = TYPE_CONTEXT (t2); break;
745 case 'x': t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
752 /* The C standard says that two structures in different translation
753 units are compatible with each other only if the types of their
754 fields are compatible (among other things). So, consider two copies
755 of this structure: */
757 struct tagged_tu_seen {
758 const struct tagged_tu_seen * next;
763 /* Can they be compatible with each other? We choose to break the
764 recursion by allowing those types to be compatible. */
766 static const struct tagged_tu_seen * tagged_tu_seen_base;
768 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
769 compatible. If the two types are not the same (which has been
770 checked earlier), this can only happen when multiple translation
771 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
775 tagged_types_tu_compatible_p (tree t1, tree t2, int flags)
778 bool needs_warning = false;
780 /* We have to verify that the tags of the types are the same. This
781 is harder than it looks because this may be a typedef, so we have
782 to go look at the original type. It may even be a typedef of a
784 In the case of compiler-created builtin structs the TYPE_DECL
785 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
786 while (TYPE_NAME (t1)
787 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
788 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
789 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
791 while (TYPE_NAME (t2)
792 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
793 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
794 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
796 /* C90 didn't have the requirement that the two tags be the same. */
797 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
800 /* C90 didn't say what happened if one or both of the types were
801 incomplete; we choose to follow C99 rules here, which is that they
803 if (TYPE_SIZE (t1) == NULL
804 || TYPE_SIZE (t2) == NULL)
808 const struct tagged_tu_seen * tts_i;
809 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
810 if (tts_i->t1 == t1 && tts_i->t2 == t2)
814 switch (TREE_CODE (t1))
819 /* Speed up the case where the type values are in the same order. */
820 tree tv1 = TYPE_VALUES (t1);
821 tree tv2 = TYPE_VALUES (t2);
826 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
828 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
830 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
834 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
836 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
839 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
842 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
844 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
846 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
854 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
857 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
860 struct tagged_tu_seen tts;
862 tts.next = tagged_tu_seen_base;
865 tagged_tu_seen_base = &tts;
867 if (DECL_NAME (s1) != NULL)
868 for (s2 = TYPE_VALUES (t2); s2; s2 = TREE_CHAIN (s2))
869 if (DECL_NAME (s1) == DECL_NAME (s2))
872 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2), flags);
876 needs_warning = true;
878 if (TREE_CODE (s1) == FIELD_DECL
879 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
880 DECL_FIELD_BIT_OFFSET (s2)) != 1)
886 tagged_tu_seen_base = tts.next;
890 return needs_warning ? 2 : 1;
895 struct tagged_tu_seen tts;
897 tts.next = tagged_tu_seen_base;
900 tagged_tu_seen_base = &tts;
902 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
904 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
907 if (TREE_CODE (s1) != TREE_CODE (s2)
908 || DECL_NAME (s1) != DECL_NAME (s2))
910 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2), flags);
914 needs_warning = true;
916 if (TREE_CODE (s1) == FIELD_DECL
917 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
918 DECL_FIELD_BIT_OFFSET (s2)) != 1)
921 tagged_tu_seen_base = tts.next;
924 return needs_warning ? 2 : 1;
932 /* Return 1 if two function types F1 and F2 are compatible.
933 If either type specifies no argument types,
934 the other must specify a fixed number of self-promoting arg types.
935 Otherwise, if one type specifies only the number of arguments,
936 the other must specify that number of self-promoting arg types.
937 Otherwise, the argument types must match. */
940 function_types_compatible_p (tree f1, tree f2, int flags)
943 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
948 ret1 = TREE_TYPE (f1);
949 ret2 = TREE_TYPE (f2);
951 /* 'volatile' qualifiers on a function's return type mean the function
953 if (pedantic && TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
954 pedwarn ("function return types not compatible due to `volatile'");
955 if (TYPE_VOLATILE (ret1))
956 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
957 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
958 if (TYPE_VOLATILE (ret2))
959 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
960 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
961 val = comptypes (ret1, ret2, flags);
965 args1 = TYPE_ARG_TYPES (f1);
966 args2 = TYPE_ARG_TYPES (f2);
968 /* An unspecified parmlist matches any specified parmlist
969 whose argument types don't need default promotions. */
973 if (!self_promoting_args_p (args2))
975 /* If one of these types comes from a non-prototype fn definition,
976 compare that with the other type's arglist.
977 If they don't match, ask for a warning (but no error). */
978 if (TYPE_ACTUAL_ARG_TYPES (f1)
979 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1),
986 if (!self_promoting_args_p (args1))
988 if (TYPE_ACTUAL_ARG_TYPES (f2)
989 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2),
995 /* Both types have argument lists: compare them and propagate results. */
996 val1 = type_lists_compatible_p (args1, args2, flags);
997 return val1 != 1 ? val1 : val;
1000 /* Check two lists of types for compatibility,
1001 returning 0 for incompatible, 1 for compatible,
1002 or 2 for compatible with warning. */
1005 type_lists_compatible_p (tree args1, tree args2, int flags)
1007 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1013 if (args1 == 0 && args2 == 0)
1015 /* If one list is shorter than the other,
1016 they fail to match. */
1017 if (args1 == 0 || args2 == 0)
1019 /* A null pointer instead of a type
1020 means there is supposed to be an argument
1021 but nothing is specified about what type it has.
1022 So match anything that self-promotes. */
1023 if (TREE_VALUE (args1) == 0)
1025 if (c_type_promotes_to (TREE_VALUE (args2)) != TREE_VALUE (args2))
1028 else if (TREE_VALUE (args2) == 0)
1030 if (c_type_promotes_to (TREE_VALUE (args1)) != TREE_VALUE (args1))
1033 /* If one of the lists has an error marker, ignore this arg. */
1034 else if (TREE_CODE (TREE_VALUE (args1)) == ERROR_MARK
1035 || TREE_CODE (TREE_VALUE (args2)) == ERROR_MARK)
1037 else if (! (newval = comptypes (TYPE_MAIN_VARIANT (TREE_VALUE (args1)),
1038 TYPE_MAIN_VARIANT (TREE_VALUE (args2)),
1041 /* Allow wait (union {union wait *u; int *i} *)
1042 and wait (union wait *) to be compatible. */
1043 if (TREE_CODE (TREE_VALUE (args1)) == UNION_TYPE
1044 && (TYPE_NAME (TREE_VALUE (args1)) == 0
1045 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args1)))
1046 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args1))) == INTEGER_CST
1047 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args1)),
1048 TYPE_SIZE (TREE_VALUE (args2))))
1051 for (memb = TYPE_FIELDS (TREE_VALUE (args1));
1052 memb; memb = TREE_CHAIN (memb))
1053 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args2),
1059 else if (TREE_CODE (TREE_VALUE (args2)) == UNION_TYPE
1060 && (TYPE_NAME (TREE_VALUE (args2)) == 0
1061 || TYPE_TRANSPARENT_UNION (TREE_VALUE (args2)))
1062 && TREE_CODE (TYPE_SIZE (TREE_VALUE (args2))) == INTEGER_CST
1063 && tree_int_cst_equal (TYPE_SIZE (TREE_VALUE (args2)),
1064 TYPE_SIZE (TREE_VALUE (args1))))
1067 for (memb = TYPE_FIELDS (TREE_VALUE (args2));
1068 memb; memb = TREE_CHAIN (memb))
1069 if (comptypes (TREE_TYPE (memb), TREE_VALUE (args1),
1079 /* comptypes said ok, but record if it said to warn. */
1083 args1 = TREE_CHAIN (args1);
1084 args2 = TREE_CHAIN (args2);
1088 /* Compute the size to increment a pointer by. */
1091 c_size_in_bytes (tree type)
1093 enum tree_code code = TREE_CODE (type);
1095 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1096 return size_one_node;
1098 if (!COMPLETE_OR_VOID_TYPE_P (type))
1100 error ("arithmetic on pointer to an incomplete type");
1101 return size_one_node;
1104 /* Convert in case a char is more than one unit. */
1105 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1106 size_int (TYPE_PRECISION (char_type_node)
1110 /* Return either DECL or its known constant value (if it has one). */
1113 decl_constant_value (tree decl)
1115 if (/* Don't change a variable array bound or initial value to a constant
1116 in a place where a variable is invalid. Note that DECL_INITIAL
1117 isn't valid for a PARM_DECL. */
1118 current_function_decl != 0
1119 && TREE_CODE (decl) != PARM_DECL
1120 && ! TREE_THIS_VOLATILE (decl)
1121 && TREE_READONLY (decl)
1122 && DECL_INITIAL (decl) != 0
1123 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1124 /* This is invalid if initial value is not constant.
1125 If it has either a function call, a memory reference,
1126 or a variable, then re-evaluating it could give different results. */
1127 && TREE_CONSTANT (DECL_INITIAL (decl))
1128 /* Check for cases where this is sub-optimal, even though valid. */
1129 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1130 return DECL_INITIAL (decl);
1134 /* Return either DECL or its known constant value (if it has one), but
1135 return DECL if pedantic or DECL has mode BLKmode. This is for
1136 bug-compatibility with the old behavior of decl_constant_value
1137 (before GCC 3.0); every use of this function is a bug and it should
1138 be removed before GCC 3.1. It is not appropriate to use pedantic
1139 in a way that affects optimization, and BLKmode is probably not the
1140 right test for avoiding misoptimizations either. */
1143 decl_constant_value_for_broken_optimization (tree decl)
1145 if (pedantic || DECL_MODE (decl) == BLKmode)
1148 return decl_constant_value (decl);
1152 /* Perform the default conversion of arrays and functions to pointers.
1153 Return the result of converting EXP. For any other expression, just
1157 default_function_array_conversion (tree exp)
1160 tree type = TREE_TYPE (exp);
1161 enum tree_code code = TREE_CODE (type);
1164 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1167 Do not use STRIP_NOPS here! It will remove conversions from pointer
1168 to integer and cause infinite recursion. */
1170 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1171 || (TREE_CODE (exp) == NOP_EXPR
1172 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1174 if (TREE_CODE (exp) == NON_LVALUE_EXPR)
1176 exp = TREE_OPERAND (exp, 0);
1179 /* Preserve the original expression code. */
1180 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (exp))))
1181 C_SET_EXP_ORIGINAL_CODE (exp, C_EXP_ORIGINAL_CODE (orig_exp));
1183 if (code == FUNCTION_TYPE)
1185 return build_unary_op (ADDR_EXPR, exp, 0);
1187 if (code == ARRAY_TYPE)
1190 tree restype = TREE_TYPE (type);
1196 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'r' || DECL_P (exp))
1198 constp = TREE_READONLY (exp);
1199 volatilep = TREE_THIS_VOLATILE (exp);
1202 if (TYPE_QUALS (type) || constp || volatilep)
1204 = c_build_qualified_type (restype,
1206 | (constp * TYPE_QUAL_CONST)
1207 | (volatilep * TYPE_QUAL_VOLATILE));
1209 if (TREE_CODE (exp) == INDIRECT_REF)
1210 return convert (TYPE_POINTER_TO (restype),
1211 TREE_OPERAND (exp, 0));
1213 if (TREE_CODE (exp) == COMPOUND_EXPR)
1215 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1216 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1217 TREE_OPERAND (exp, 0), op1);
1220 lvalue_array_p = !not_lvalue && lvalue_p (exp);
1221 if (!flag_isoc99 && !lvalue_array_p)
1223 /* Before C99, non-lvalue arrays do not decay to pointers.
1224 Normally, using such an array would be invalid; but it can
1225 be used correctly inside sizeof or as a statement expression.
1226 Thus, do not give an error here; an error will result later. */
1230 ptrtype = build_pointer_type (restype);
1232 if (TREE_CODE (exp) == VAR_DECL)
1234 /* ??? This is not really quite correct
1235 in that the type of the operand of ADDR_EXPR
1236 is not the target type of the type of the ADDR_EXPR itself.
1237 Question is, can this lossage be avoided? */
1238 adr = build1 (ADDR_EXPR, ptrtype, exp);
1239 if (!c_mark_addressable (exp))
1240 return error_mark_node;
1241 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1244 /* This way is better for a COMPONENT_REF since it can
1245 simplify the offset for a component. */
1246 adr = build_unary_op (ADDR_EXPR, exp, 1);
1247 return convert (ptrtype, adr);
1252 /* Perform default promotions for C data used in expressions.
1253 Arrays and functions are converted to pointers;
1254 enumeral types or short or char, to int.
1255 In addition, manifest constants symbols are replaced by their values. */
1258 default_conversion (tree exp)
1261 tree type = TREE_TYPE (exp);
1262 enum tree_code code = TREE_CODE (type);
1264 if (code == FUNCTION_TYPE || code == ARRAY_TYPE)
1265 return default_function_array_conversion (exp);
1267 /* Constants can be used directly unless they're not loadable. */
1268 if (TREE_CODE (exp) == CONST_DECL)
1269 exp = DECL_INITIAL (exp);
1271 /* Replace a nonvolatile const static variable with its value unless
1272 it is an array, in which case we must be sure that taking the
1273 address of the array produces consistent results. */
1274 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1276 exp = decl_constant_value_for_broken_optimization (exp);
1277 type = TREE_TYPE (exp);
1280 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1283 Do not use STRIP_NOPS here! It will remove conversions from pointer
1284 to integer and cause infinite recursion. */
1286 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1287 || (TREE_CODE (exp) == NOP_EXPR
1288 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1289 exp = TREE_OPERAND (exp, 0);
1291 /* Preserve the original expression code. */
1292 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (exp))))
1293 C_SET_EXP_ORIGINAL_CODE (exp, C_EXP_ORIGINAL_CODE (orig_exp));
1295 /* Normally convert enums to int,
1296 but convert wide enums to something wider. */
1297 if (code == ENUMERAL_TYPE)
1299 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1300 TYPE_PRECISION (integer_type_node)),
1301 ((TYPE_PRECISION (type)
1302 >= TYPE_PRECISION (integer_type_node))
1303 && TYPE_UNSIGNED (type)));
1305 return convert (type, exp);
1308 if (TREE_CODE (exp) == COMPONENT_REF
1309 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1310 /* If it's thinner than an int, promote it like a
1311 c_promoting_integer_type_p, otherwise leave it alone. */
1312 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1313 TYPE_PRECISION (integer_type_node)))
1314 return convert (integer_type_node, exp);
1316 if (c_promoting_integer_type_p (type))
1318 /* Preserve unsignedness if not really getting any wider. */
1319 if (TYPE_UNSIGNED (type)
1320 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1321 return convert (unsigned_type_node, exp);
1323 return convert (integer_type_node, exp);
1326 if (code == VOID_TYPE)
1328 error ("void value not ignored as it ought to be");
1329 return error_mark_node;
1334 /* Look up COMPONENT in a structure or union DECL.
1336 If the component name is not found, returns NULL_TREE. Otherwise,
1337 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1338 stepping down the chain to the component, which is in the last
1339 TREE_VALUE of the list. Normally the list is of length one, but if
1340 the component is embedded within (nested) anonymous structures or
1341 unions, the list steps down the chain to the component. */
1344 lookup_field (tree decl, tree component)
1346 tree type = TREE_TYPE (decl);
1349 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1350 to the field elements. Use a binary search on this array to quickly
1351 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1352 will always be set for structures which have many elements. */
1354 if (TYPE_LANG_SPECIFIC (type))
1357 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1359 field = TYPE_FIELDS (type);
1361 top = TYPE_LANG_SPECIFIC (type)->s->len;
1362 while (top - bot > 1)
1364 half = (top - bot + 1) >> 1;
1365 field = field_array[bot+half];
1367 if (DECL_NAME (field) == NULL_TREE)
1369 /* Step through all anon unions in linear fashion. */
1370 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1372 field = field_array[bot++];
1373 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1374 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1376 tree anon = lookup_field (field, component);
1379 return tree_cons (NULL_TREE, field, anon);
1383 /* Entire record is only anon unions. */
1387 /* Restart the binary search, with new lower bound. */
1391 if (DECL_NAME (field) == component)
1393 if (DECL_NAME (field) < component)
1399 if (DECL_NAME (field_array[bot]) == component)
1400 field = field_array[bot];
1401 else if (DECL_NAME (field) != component)
1406 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1408 if (DECL_NAME (field) == NULL_TREE
1409 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1410 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1412 tree anon = lookup_field (field, component);
1415 return tree_cons (NULL_TREE, field, anon);
1418 if (DECL_NAME (field) == component)
1422 if (field == NULL_TREE)
1426 return tree_cons (NULL_TREE, field, NULL_TREE);
1429 /* Make an expression to refer to the COMPONENT field of
1430 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1433 build_component_ref (tree datum, tree component)
1435 tree type = TREE_TYPE (datum);
1436 enum tree_code code = TREE_CODE (type);
1440 if (!objc_is_public (datum, component))
1441 return error_mark_node;
1443 /* If DATUM is a COMPOUND_EXPR, move our reference inside it.
1444 Ensure that the arguments are not lvalues; otherwise,
1445 if the component is an array, it would wrongly decay to a pointer in
1447 We cannot do this with a COND_EXPR, because in a conditional expression
1448 the default promotions are applied to both sides, and this would yield
1449 the wrong type of the result; for example, if the components have
1451 switch (TREE_CODE (datum))
1455 tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
1456 return build (COMPOUND_EXPR, TREE_TYPE (value),
1457 TREE_OPERAND (datum, 0), non_lvalue (value));
1463 /* See if there is a field or component with name COMPONENT. */
1465 if (code == RECORD_TYPE || code == UNION_TYPE)
1467 if (!COMPLETE_TYPE_P (type))
1469 c_incomplete_type_error (NULL_TREE, type);
1470 return error_mark_node;
1473 field = lookup_field (datum, component);
1477 error ("%s has no member named `%s'",
1478 code == RECORD_TYPE ? "structure" : "union",
1479 IDENTIFIER_POINTER (component));
1480 return error_mark_node;
1483 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1484 This might be better solved in future the way the C++ front
1485 end does it - by giving the anonymous entities each a
1486 separate name and type, and then have build_component_ref
1487 recursively call itself. We can't do that here. */
1490 tree subdatum = TREE_VALUE (field);
1492 if (TREE_TYPE (subdatum) == error_mark_node)
1493 return error_mark_node;
1495 ref = build (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum);
1496 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1497 TREE_READONLY (ref) = 1;
1498 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1499 TREE_THIS_VOLATILE (ref) = 1;
1501 if (TREE_DEPRECATED (subdatum))
1502 warn_deprecated_use (subdatum);
1506 field = TREE_CHAIN (field);
1512 else if (code != ERROR_MARK)
1513 error ("request for member `%s' in something not a structure or union",
1514 IDENTIFIER_POINTER (component));
1516 return error_mark_node;
1519 /* Given an expression PTR for a pointer, return an expression
1520 for the value pointed to.
1521 ERRORSTRING is the name of the operator to appear in error messages. */
1524 build_indirect_ref (tree ptr, const char *errorstring)
1526 tree pointer = default_conversion (ptr);
1527 tree type = TREE_TYPE (pointer);
1529 if (TREE_CODE (type) == POINTER_TYPE)
1531 if (TREE_CODE (pointer) == ADDR_EXPR
1532 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1533 == TREE_TYPE (type)))
1534 return TREE_OPERAND (pointer, 0);
1537 tree t = TREE_TYPE (type);
1538 tree ref = build1 (INDIRECT_REF, TYPE_MAIN_VARIANT (t), pointer);
1540 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1542 error ("dereferencing pointer to incomplete type");
1543 return error_mark_node;
1545 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1546 warning ("dereferencing `void *' pointer");
1548 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1549 so that we get the proper error message if the result is used
1550 to assign to. Also, &* is supposed to be a no-op.
1551 And ANSI C seems to specify that the type of the result
1552 should be the const type. */
1553 /* A de-reference of a pointer to const is not a const. It is valid
1554 to change it via some other pointer. */
1555 TREE_READONLY (ref) = TYPE_READONLY (t);
1556 TREE_SIDE_EFFECTS (ref)
1557 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1558 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1562 else if (TREE_CODE (pointer) != ERROR_MARK)
1563 error ("invalid type argument of `%s'", errorstring);
1564 return error_mark_node;
1567 /* This handles expressions of the form "a[i]", which denotes
1570 This is logically equivalent in C to *(a+i), but we may do it differently.
1571 If A is a variable or a member, we generate a primitive ARRAY_REF.
1572 This avoids forcing the array out of registers, and can work on
1573 arrays that are not lvalues (for example, members of structures returned
1577 build_array_ref (tree array, tree index)
1581 error ("subscript missing in array reference");
1582 return error_mark_node;
1585 if (TREE_TYPE (array) == error_mark_node
1586 || TREE_TYPE (index) == error_mark_node)
1587 return error_mark_node;
1589 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1593 /* Subscripting with type char is likely to lose
1594 on a machine where chars are signed.
1595 So warn on any machine, but optionally.
1596 Don't warn for unsigned char since that type is safe.
1597 Don't warn for signed char because anyone who uses that
1598 must have done so deliberately. */
1599 if (warn_char_subscripts
1600 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1601 warning ("array subscript has type `char'");
1603 /* Apply default promotions *after* noticing character types. */
1604 index = default_conversion (index);
1606 /* Require integer *after* promotion, for sake of enums. */
1607 if (TREE_CODE (TREE_TYPE (index)) != INTEGER_TYPE)
1609 error ("array subscript is not an integer");
1610 return error_mark_node;
1613 /* An array that is indexed by a non-constant
1614 cannot be stored in a register; we must be able to do
1615 address arithmetic on its address.
1616 Likewise an array of elements of variable size. */
1617 if (TREE_CODE (index) != INTEGER_CST
1618 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1619 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1621 if (!c_mark_addressable (array))
1622 return error_mark_node;
1624 /* An array that is indexed by a constant value which is not within
1625 the array bounds cannot be stored in a register either; because we
1626 would get a crash in store_bit_field/extract_bit_field when trying
1627 to access a non-existent part of the register. */
1628 if (TREE_CODE (index) == INTEGER_CST
1629 && TYPE_DOMAIN (TREE_TYPE (array))
1630 && ! int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1632 if (!c_mark_addressable (array))
1633 return error_mark_node;
1639 while (TREE_CODE (foo) == COMPONENT_REF)
1640 foo = TREE_OPERAND (foo, 0);
1641 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1642 pedwarn ("ISO C forbids subscripting `register' array");
1643 else if (! flag_isoc99 && ! lvalue_p (foo))
1644 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1647 type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (array)));
1648 rval = build (ARRAY_REF, type, array, index);
1649 /* Array ref is const/volatile if the array elements are
1650 or if the array is. */
1651 TREE_READONLY (rval)
1652 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1653 | TREE_READONLY (array));
1654 TREE_SIDE_EFFECTS (rval)
1655 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1656 | TREE_SIDE_EFFECTS (array));
1657 TREE_THIS_VOLATILE (rval)
1658 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1659 /* This was added by rms on 16 Nov 91.
1660 It fixes vol struct foo *a; a->elts[1]
1661 in an inline function.
1662 Hope it doesn't break something else. */
1663 | TREE_THIS_VOLATILE (array));
1664 return require_complete_type (fold (rval));
1668 tree ar = default_conversion (array);
1669 tree ind = default_conversion (index);
1671 /* Do the same warning check as above, but only on the part that's
1672 syntactically the index and only if it is also semantically
1674 if (warn_char_subscripts
1675 && TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE
1676 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1677 warning ("subscript has type `char'");
1679 /* Put the integer in IND to simplify error checking. */
1680 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
1687 if (ar == error_mark_node)
1690 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE
1691 || TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) == FUNCTION_TYPE)
1693 error ("subscripted value is neither array nor pointer");
1694 return error_mark_node;
1696 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
1698 error ("array subscript is not an integer");
1699 return error_mark_node;
1702 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, ind, 0),
1707 /* Build an external reference to identifier ID. FUN indicates
1708 whether this will be used for a function call. */
1710 build_external_ref (tree id, int fun)
1713 tree decl = lookup_name (id);
1714 tree objc_ivar = lookup_objc_ivar (id);
1716 if (decl && decl != error_mark_node)
1718 /* Properly declared variable or function reference. */
1721 else if (decl != objc_ivar && !DECL_FILE_SCOPE_P (decl))
1723 warning ("local declaration of `%s' hides instance variable",
1724 IDENTIFIER_POINTER (id));
1733 /* Implicit function declaration. */
1734 ref = implicitly_declare (id);
1735 else if (decl == error_mark_node)
1736 /* Don't complain about something that's already been
1737 complained about. */
1738 return error_mark_node;
1741 undeclared_variable (id);
1742 return error_mark_node;
1745 if (TREE_TYPE (ref) == error_mark_node)
1746 return error_mark_node;
1748 if (TREE_DEPRECATED (ref))
1749 warn_deprecated_use (ref);
1751 if (!skip_evaluation)
1752 assemble_external (ref);
1753 TREE_USED (ref) = 1;
1755 if (TREE_CODE (ref) == CONST_DECL)
1757 ref = DECL_INITIAL (ref);
1758 TREE_CONSTANT (ref) = 1;
1759 TREE_INVARIANT (ref) = 1;
1761 else if (current_function_decl != 0
1762 && !DECL_FILE_SCOPE_P (current_function_decl)
1763 && (TREE_CODE (ref) == VAR_DECL
1764 || TREE_CODE (ref) == PARM_DECL
1765 || TREE_CODE (ref) == FUNCTION_DECL))
1767 tree context = decl_function_context (ref);
1769 if (context != 0 && context != current_function_decl)
1770 DECL_NONLOCAL (ref) = 1;
1776 /* Build a function call to function FUNCTION with parameters PARAMS.
1777 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1778 TREE_VALUE of each node is a parameter-expression.
1779 FUNCTION's data type may be a function type or a pointer-to-function. */
1782 build_function_call (tree function, tree params)
1784 tree fntype, fundecl = 0;
1785 tree coerced_params;
1786 tree name = NULL_TREE, result;
1789 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1790 STRIP_TYPE_NOPS (function);
1792 /* Convert anything with function type to a pointer-to-function. */
1793 if (TREE_CODE (function) == FUNCTION_DECL)
1795 name = DECL_NAME (function);
1797 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1798 (because calling an inline function does not mean the function
1799 needs to be separately compiled). */
1800 fntype = build_type_variant (TREE_TYPE (function),
1801 TREE_READONLY (function),
1802 TREE_THIS_VOLATILE (function));
1804 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
1807 function = default_conversion (function);
1809 fntype = TREE_TYPE (function);
1811 if (TREE_CODE (fntype) == ERROR_MARK)
1812 return error_mark_node;
1814 if (!(TREE_CODE (fntype) == POINTER_TYPE
1815 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
1817 error ("called object is not a function");
1818 return error_mark_node;
1821 if (fundecl && TREE_THIS_VOLATILE (fundecl))
1822 current_function_returns_abnormally = 1;
1824 /* fntype now gets the type of function pointed to. */
1825 fntype = TREE_TYPE (fntype);
1827 /* Check that the function is called through a compatible prototype.
1828 If it is not, replace the call by a trap, wrapped up in a compound
1829 expression if necessary. This has the nice side-effect to prevent
1830 the tree-inliner from generating invalid assignment trees which may
1831 blow up in the RTL expander later.
1833 ??? This doesn't work for Objective-C because objc_comptypes
1834 refuses to compare function prototypes, yet the compiler appears
1835 to build calls that are flagged as invalid by C's comptypes. */
1836 if (! c_dialect_objc ()
1837 && TREE_CODE (function) == NOP_EXPR
1838 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
1839 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
1840 && ! comptypes (fntype, TREE_TYPE (tem), COMPARE_STRICT))
1842 tree return_type = TREE_TYPE (fntype);
1843 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
1846 /* This situation leads to run-time undefined behavior. We can't,
1847 therefore, simply error unless we can prove that all possible
1848 executions of the program must execute the code. */
1849 warning ("function called through a non-compatible type");
1851 /* We can, however, treat "undefined" any way we please.
1852 Call abort to encourage the user to fix the program. */
1853 inform ("if this code is reached, the program will abort");
1855 if (VOID_TYPE_P (return_type))
1861 if (AGGREGATE_TYPE_P (return_type))
1862 rhs = build_compound_literal (return_type,
1863 build_constructor (return_type,
1866 rhs = fold (build1 (NOP_EXPR, return_type, integer_zero_node));
1868 return build (COMPOUND_EXPR, return_type, trap, rhs);
1872 /* Convert the parameters to the types declared in the
1873 function prototype, or apply default promotions. */
1876 = convert_arguments (TYPE_ARG_TYPES (fntype), params, name, fundecl);
1878 /* Check that the arguments to the function are valid. */
1880 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params);
1882 /* Recognize certain built-in functions so we can make tree-codes
1883 other than CALL_EXPR. We do this when it enables fold-const.c
1884 to do something useful. */
1886 if (TREE_CODE (function) == ADDR_EXPR
1887 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
1888 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
1890 result = expand_tree_builtin (TREE_OPERAND (function, 0),
1891 params, coerced_params);
1896 result = build (CALL_EXPR, TREE_TYPE (fntype),
1897 function, coerced_params, NULL_TREE);
1898 TREE_SIDE_EFFECTS (result) = 1;
1900 if (require_constant_value)
1902 result = fold_initializer (result);
1904 if (TREE_CONSTANT (result)
1905 && (name == NULL_TREE
1906 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
1907 pedwarn_init ("initializer element is not constant");
1910 result = fold (result);
1912 if (VOID_TYPE_P (TREE_TYPE (result)))
1914 return require_complete_type (result);
1917 /* Convert the argument expressions in the list VALUES
1918 to the types in the list TYPELIST. The result is a list of converted
1919 argument expressions.
1921 If TYPELIST is exhausted, or when an element has NULL as its type,
1922 perform the default conversions.
1924 PARMLIST is the chain of parm decls for the function being called.
1925 It may be 0, if that info is not available.
1926 It is used only for generating error messages.
1928 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
1930 This is also where warnings about wrong number of args are generated.
1932 Both VALUES and the returned value are chains of TREE_LIST nodes
1933 with the elements of the list in the TREE_VALUE slots of those nodes. */
1936 convert_arguments (tree typelist, tree values, tree name, tree fundecl)
1938 tree typetail, valtail;
1942 /* Scan the given expressions and types, producing individual
1943 converted arguments and pushing them on RESULT in reverse order. */
1945 for (valtail = values, typetail = typelist, parmnum = 0;
1947 valtail = TREE_CHAIN (valtail), parmnum++)
1949 tree type = typetail ? TREE_VALUE (typetail) : 0;
1950 tree val = TREE_VALUE (valtail);
1952 if (type == void_type_node)
1955 error ("too many arguments to function `%s'",
1956 IDENTIFIER_POINTER (name));
1958 error ("too many arguments to function");
1962 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
1963 /* Do not use STRIP_NOPS here! We do not want an enumerator with value 0
1964 to convert automatically to a pointer. */
1965 if (TREE_CODE (val) == NON_LVALUE_EXPR)
1966 val = TREE_OPERAND (val, 0);
1968 val = default_function_array_conversion (val);
1970 val = require_complete_type (val);
1974 /* Formal parm type is specified by a function prototype. */
1977 if (!COMPLETE_TYPE_P (type))
1979 error ("type of formal parameter %d is incomplete", parmnum + 1);
1984 /* Optionally warn about conversions that
1985 differ from the default conversions. */
1986 if (warn_conversion || warn_traditional)
1988 int formal_prec = TYPE_PRECISION (type);
1990 if (INTEGRAL_TYPE_P (type)
1991 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1992 warn_for_assignment ("%s as integer rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1993 if (INTEGRAL_TYPE_P (type)
1994 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
1995 warn_for_assignment ("%s as integer rather than complex due to prototype", (char *) 0, name, parmnum + 1);
1996 else if (TREE_CODE (type) == COMPLEX_TYPE
1997 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
1998 warn_for_assignment ("%s as complex rather than floating due to prototype", (char *) 0, name, parmnum + 1);
1999 else if (TREE_CODE (type) == REAL_TYPE
2000 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2001 warn_for_assignment ("%s as floating rather than integer due to prototype", (char *) 0, name, parmnum + 1);
2002 else if (TREE_CODE (type) == COMPLEX_TYPE
2003 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2004 warn_for_assignment ("%s as complex rather than integer due to prototype", (char *) 0, name, parmnum + 1);
2005 else if (TREE_CODE (type) == REAL_TYPE
2006 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2007 warn_for_assignment ("%s as floating rather than complex due to prototype", (char *) 0, name, parmnum + 1);
2008 /* ??? At some point, messages should be written about
2009 conversions between complex types, but that's too messy
2011 else if (TREE_CODE (type) == REAL_TYPE
2012 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2014 /* Warn if any argument is passed as `float',
2015 since without a prototype it would be `double'. */
2016 if (formal_prec == TYPE_PRECISION (float_type_node))
2017 warn_for_assignment ("%s as `float' rather than `double' due to prototype", (char *) 0, name, parmnum + 1);
2019 /* Detect integer changing in width or signedness.
2020 These warnings are only activated with
2021 -Wconversion, not with -Wtraditional. */
2022 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2023 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2025 tree would_have_been = default_conversion (val);
2026 tree type1 = TREE_TYPE (would_have_been);
2028 if (TREE_CODE (type) == ENUMERAL_TYPE
2029 && (TYPE_MAIN_VARIANT (type)
2030 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2031 /* No warning if function asks for enum
2032 and the actual arg is that enum type. */
2034 else if (formal_prec != TYPE_PRECISION (type1))
2035 warn_for_assignment ("%s with different width due to prototype", (char *) 0, name, parmnum + 1);
2036 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2038 /* Don't complain if the formal parameter type
2039 is an enum, because we can't tell now whether
2040 the value was an enum--even the same enum. */
2041 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2043 else if (TREE_CODE (val) == INTEGER_CST
2044 && int_fits_type_p (val, type))
2045 /* Change in signedness doesn't matter
2046 if a constant value is unaffected. */
2048 /* Likewise for a constant in a NOP_EXPR. */
2049 else if (TREE_CODE (val) == NOP_EXPR
2050 && TREE_CODE (TREE_OPERAND (val, 0)) == INTEGER_CST
2051 && int_fits_type_p (TREE_OPERAND (val, 0), type))
2053 /* If the value is extended from a narrower
2054 unsigned type, it doesn't matter whether we
2055 pass it as signed or unsigned; the value
2056 certainly is the same either way. */
2057 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2058 && TYPE_UNSIGNED (TREE_TYPE (val)))
2060 else if (TYPE_UNSIGNED (type))
2061 warn_for_assignment ("%s as unsigned due to prototype", (char *) 0, name, parmnum + 1);
2063 warn_for_assignment ("%s as signed due to prototype", (char *) 0, name, parmnum + 1);
2067 parmval = convert_for_assignment (type, val,
2068 (char *) 0, /* arg passing */
2069 fundecl, name, parmnum + 1);
2071 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2072 && INTEGRAL_TYPE_P (type)
2073 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2074 parmval = default_conversion (parmval);
2076 result = tree_cons (NULL_TREE, parmval, result);
2078 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2079 && (TYPE_PRECISION (TREE_TYPE (val))
2080 < TYPE_PRECISION (double_type_node)))
2081 /* Convert `float' to `double'. */
2082 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2084 /* Convert `short' and `char' to full-size `int'. */
2085 result = tree_cons (NULL_TREE, default_conversion (val), result);
2088 typetail = TREE_CHAIN (typetail);
2091 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2094 error ("too few arguments to function `%s'",
2095 IDENTIFIER_POINTER (name));
2097 error ("too few arguments to function");
2100 return nreverse (result);
2103 /* This is the entry point used by the parser
2104 for binary operators in the input.
2105 In addition to constructing the expression,
2106 we check for operands that were written with other binary operators
2107 in a way that is likely to confuse the user. */
2110 parser_build_binary_op (enum tree_code code, tree arg1, tree arg2)
2112 tree result = build_binary_op (code, arg1, arg2, 1);
2115 char class1 = TREE_CODE_CLASS (TREE_CODE (arg1));
2116 char class2 = TREE_CODE_CLASS (TREE_CODE (arg2));
2117 enum tree_code code1 = ERROR_MARK;
2118 enum tree_code code2 = ERROR_MARK;
2120 if (TREE_CODE (result) == ERROR_MARK)
2121 return error_mark_node;
2123 if (IS_EXPR_CODE_CLASS (class1))
2124 code1 = C_EXP_ORIGINAL_CODE (arg1);
2125 if (IS_EXPR_CODE_CLASS (class2))
2126 code2 = C_EXP_ORIGINAL_CODE (arg2);
2128 /* Check for cases such as x+y<<z which users are likely
2129 to misinterpret. If parens are used, C_EXP_ORIGINAL_CODE
2130 is cleared to prevent these warnings. */
2131 if (warn_parentheses)
2133 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2135 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2136 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2137 warning ("suggest parentheses around + or - inside shift");
2140 if (code == TRUTH_ORIF_EXPR)
2142 if (code1 == TRUTH_ANDIF_EXPR
2143 || code2 == TRUTH_ANDIF_EXPR)
2144 warning ("suggest parentheses around && within ||");
2147 if (code == BIT_IOR_EXPR)
2149 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2150 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2151 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2152 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2153 warning ("suggest parentheses around arithmetic in operand of |");
2154 /* Check cases like x|y==z */
2155 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
2156 warning ("suggest parentheses around comparison in operand of |");
2159 if (code == BIT_XOR_EXPR)
2161 if (code1 == BIT_AND_EXPR
2162 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2163 || code2 == BIT_AND_EXPR
2164 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2165 warning ("suggest parentheses around arithmetic in operand of ^");
2166 /* Check cases like x^y==z */
2167 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
2168 warning ("suggest parentheses around comparison in operand of ^");
2171 if (code == BIT_AND_EXPR)
2173 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2174 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2175 warning ("suggest parentheses around + or - in operand of &");
2176 /* Check cases like x&y==z */
2177 if (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<')
2178 warning ("suggest parentheses around comparison in operand of &");
2182 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2183 if (TREE_CODE_CLASS (code) == '<' && extra_warnings
2184 && (TREE_CODE_CLASS (code1) == '<' || TREE_CODE_CLASS (code2) == '<'))
2185 warning ("comparisons like X<=Y<=Z do not have their mathematical meaning");
2187 unsigned_conversion_warning (result, arg1);
2188 unsigned_conversion_warning (result, arg2);
2189 overflow_warning (result);
2191 class = TREE_CODE_CLASS (TREE_CODE (result));
2193 /* Record the code that was specified in the source,
2194 for the sake of warnings about confusing nesting. */
2195 if (IS_EXPR_CODE_CLASS (class))
2196 C_SET_EXP_ORIGINAL_CODE (result, code);
2199 /* We used to use NOP_EXPR rather than NON_LVALUE_EXPR
2200 so that convert_for_assignment wouldn't strip it.
2201 That way, we got warnings for things like p = (1 - 1).
2202 But it turns out we should not get those warnings. */
2203 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
2204 C_SET_EXP_ORIGINAL_CODE (result, code);
2211 /* Return true if `t' is known to be non-negative. */
2214 c_tree_expr_nonnegative_p (tree t)
2216 if (TREE_CODE (t) == STMT_EXPR)
2218 t = COMPOUND_BODY (STMT_EXPR_STMT (t));
2220 /* Find the last statement in the chain, ignoring the final
2221 * scope statement */
2222 while (TREE_CHAIN (t) != NULL_TREE
2223 && TREE_CODE (TREE_CHAIN (t)) != SCOPE_STMT)
2225 return tree_expr_nonnegative_p (TREE_OPERAND (t, 0));
2227 return tree_expr_nonnegative_p (t);
2230 /* Return a tree for the difference of pointers OP0 and OP1.
2231 The resulting tree has type int. */
2234 pointer_diff (tree op0, tree op1)
2236 tree restype = ptrdiff_type_node;
2238 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2239 tree con0, con1, lit0, lit1;
2240 tree orig_op1 = op1;
2242 if (pedantic || warn_pointer_arith)
2244 if (TREE_CODE (target_type) == VOID_TYPE)
2245 pedwarn ("pointer of type `void *' used in subtraction");
2246 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2247 pedwarn ("pointer to a function used in subtraction");
2250 /* If the conversion to ptrdiff_type does anything like widening or
2251 converting a partial to an integral mode, we get a convert_expression
2252 that is in the way to do any simplifications.
2253 (fold-const.c doesn't know that the extra bits won't be needed.
2254 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2255 different mode in place.)
2256 So first try to find a common term here 'by hand'; we want to cover
2257 at least the cases that occur in legal static initializers. */
2258 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2259 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2261 if (TREE_CODE (con0) == PLUS_EXPR)
2263 lit0 = TREE_OPERAND (con0, 1);
2264 con0 = TREE_OPERAND (con0, 0);
2267 lit0 = integer_zero_node;
2269 if (TREE_CODE (con1) == PLUS_EXPR)
2271 lit1 = TREE_OPERAND (con1, 1);
2272 con1 = TREE_OPERAND (con1, 0);
2275 lit1 = integer_zero_node;
2277 if (operand_equal_p (con0, con1, 0))
2284 /* First do the subtraction as integers;
2285 then drop through to build the divide operator.
2286 Do not do default conversions on the minus operator
2287 in case restype is a short type. */
2289 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2290 convert (restype, op1), 0);
2291 /* This generates an error if op1 is pointer to incomplete type. */
2292 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2293 error ("arithmetic on pointer to an incomplete type");
2295 /* This generates an error if op0 is pointer to incomplete type. */
2296 op1 = c_size_in_bytes (target_type);
2298 /* Divide by the size, in easiest possible way. */
2299 return fold (build (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)));
2302 /* Construct and perhaps optimize a tree representation
2303 for a unary operation. CODE, a tree_code, specifies the operation
2304 and XARG is the operand.
2305 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2306 the default promotions (such as from short to int).
2307 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2308 allows non-lvalues; this is only used to handle conversion of non-lvalue
2309 arrays to pointers in C99. */
2312 build_unary_op (enum tree_code code, tree xarg, int flag)
2314 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2317 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2319 int noconvert = flag;
2321 if (typecode == ERROR_MARK)
2322 return error_mark_node;
2323 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2324 typecode = INTEGER_TYPE;
2329 /* This is used for unary plus, because a CONVERT_EXPR
2330 is enough to prevent anybody from looking inside for
2331 associativity, but won't generate any code. */
2332 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2333 || typecode == COMPLEX_TYPE))
2335 error ("wrong type argument to unary plus");
2336 return error_mark_node;
2338 else if (!noconvert)
2339 arg = default_conversion (arg);
2340 arg = non_lvalue (arg);
2344 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2345 || typecode == COMPLEX_TYPE
2346 || typecode == VECTOR_TYPE))
2348 error ("wrong type argument to unary minus");
2349 return error_mark_node;
2351 else if (!noconvert)
2352 arg = default_conversion (arg);
2356 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2359 arg = default_conversion (arg);
2361 else if (typecode == COMPLEX_TYPE)
2365 pedwarn ("ISO C does not support `~' for complex conjugation");
2367 arg = default_conversion (arg);
2371 error ("wrong type argument to bit-complement");
2372 return error_mark_node;
2377 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2379 error ("wrong type argument to abs");
2380 return error_mark_node;
2382 else if (!noconvert)
2383 arg = default_conversion (arg);
2387 /* Conjugating a real value is a no-op, but allow it anyway. */
2388 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2389 || typecode == COMPLEX_TYPE))
2391 error ("wrong type argument to conjugation");
2392 return error_mark_node;
2394 else if (!noconvert)
2395 arg = default_conversion (arg);
2398 case TRUTH_NOT_EXPR:
2399 if (typecode != INTEGER_TYPE
2400 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2401 && typecode != COMPLEX_TYPE
2402 /* These will convert to a pointer. */
2403 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2405 error ("wrong type argument to unary exclamation mark");
2406 return error_mark_node;
2408 arg = lang_hooks.truthvalue_conversion (arg);
2409 return invert_truthvalue (arg);
2415 if (TREE_CODE (arg) == COMPLEX_CST)
2416 return TREE_REALPART (arg);
2417 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2418 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2423 if (TREE_CODE (arg) == COMPLEX_CST)
2424 return TREE_IMAGPART (arg);
2425 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2426 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2428 return convert (TREE_TYPE (arg), integer_zero_node);
2430 case PREINCREMENT_EXPR:
2431 case POSTINCREMENT_EXPR:
2432 case PREDECREMENT_EXPR:
2433 case POSTDECREMENT_EXPR:
2435 /* Increment or decrement the real part of the value,
2436 and don't change the imaginary part. */
2437 if (typecode == COMPLEX_TYPE)
2442 pedwarn ("ISO C does not support `++' and `--' on complex types");
2444 arg = stabilize_reference (arg);
2445 real = build_unary_op (REALPART_EXPR, arg, 1);
2446 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2447 return build (COMPLEX_EXPR, TREE_TYPE (arg),
2448 build_unary_op (code, real, 1), imag);
2451 /* Report invalid types. */
2453 if (typecode != POINTER_TYPE
2454 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2456 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2457 error ("wrong type argument to increment");
2459 error ("wrong type argument to decrement");
2461 return error_mark_node;
2466 tree result_type = TREE_TYPE (arg);
2468 arg = get_unwidened (arg, 0);
2469 argtype = TREE_TYPE (arg);
2471 /* Compute the increment. */
2473 if (typecode == POINTER_TYPE)
2475 /* If pointer target is an undefined struct,
2476 we just cannot know how to do the arithmetic. */
2477 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2479 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2480 error ("increment of pointer to unknown structure");
2482 error ("decrement of pointer to unknown structure");
2484 else if ((pedantic || warn_pointer_arith)
2485 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2486 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2488 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2489 pedwarn ("wrong type argument to increment");
2491 pedwarn ("wrong type argument to decrement");
2494 inc = c_size_in_bytes (TREE_TYPE (result_type));
2497 inc = integer_one_node;
2499 inc = convert (argtype, inc);
2501 /* Complain about anything else that is not a true lvalue. */
2502 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2503 || code == POSTINCREMENT_EXPR)
2504 ? "invalid lvalue in increment"
2505 : "invalid lvalue in decrement")))
2506 return error_mark_node;
2508 /* Report a read-only lvalue. */
2509 if (TREE_READONLY (arg))
2510 readonly_error (arg,
2511 ((code == PREINCREMENT_EXPR
2512 || code == POSTINCREMENT_EXPR)
2513 ? "increment" : "decrement"));
2515 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2516 val = boolean_increment (code, arg);
2518 val = build (code, TREE_TYPE (arg), arg, inc);
2519 TREE_SIDE_EFFECTS (val) = 1;
2520 val = convert (result_type, val);
2521 if (TREE_CODE (val) != code)
2522 TREE_NO_WARNING (val) = 1;
2527 /* Note that this operation never does default_conversion. */
2529 /* Let &* cancel out to simplify resulting code. */
2530 if (TREE_CODE (arg) == INDIRECT_REF)
2532 /* Don't let this be an lvalue. */
2533 if (lvalue_p (TREE_OPERAND (arg, 0)))
2534 return non_lvalue (TREE_OPERAND (arg, 0));
2535 return TREE_OPERAND (arg, 0);
2538 /* For &x[y], return x+y */
2539 if (TREE_CODE (arg) == ARRAY_REF)
2541 if (!c_mark_addressable (TREE_OPERAND (arg, 0)))
2542 return error_mark_node;
2543 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2544 TREE_OPERAND (arg, 1), 1);
2547 /* Anything not already handled and not a true memory reference
2548 or a non-lvalue array is an error. */
2549 else if (typecode != FUNCTION_TYPE && !flag
2550 && !lvalue_or_else (arg, "invalid lvalue in unary `&'"))
2551 return error_mark_node;
2553 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2554 argtype = TREE_TYPE (arg);
2556 /* If the lvalue is const or volatile, merge that into the type
2557 to which the address will point. Note that you can't get a
2558 restricted pointer by taking the address of something, so we
2559 only have to deal with `const' and `volatile' here. */
2560 if ((DECL_P (arg) || TREE_CODE_CLASS (TREE_CODE (arg)) == 'r')
2561 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2562 argtype = c_build_type_variant (argtype,
2563 TREE_READONLY (arg),
2564 TREE_THIS_VOLATILE (arg));
2566 argtype = build_pointer_type (argtype);
2568 if (!c_mark_addressable (arg))
2569 return error_mark_node;
2574 if (TREE_CODE (arg) == COMPONENT_REF)
2576 tree field = TREE_OPERAND (arg, 1);
2578 addr = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), flag);
2580 if (DECL_C_BIT_FIELD (field))
2582 error ("attempt to take address of bit-field structure member `%s'",
2583 IDENTIFIER_POINTER (DECL_NAME (field)));
2584 return error_mark_node;
2587 addr = fold (build (PLUS_EXPR, argtype,
2588 convert (argtype, addr),
2589 convert (argtype, byte_position (field))));
2592 addr = build1 (code, argtype, arg);
2602 argtype = TREE_TYPE (arg);
2603 val = build1 (code, argtype, arg);
2604 return require_constant_value ? fold_initializer (val) : fold (val);
2607 /* Return nonzero if REF is an lvalue valid for this language.
2608 Lvalues can be assigned, unless their type has TYPE_READONLY.
2609 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2614 enum tree_code code = TREE_CODE (ref);
2621 return lvalue_p (TREE_OPERAND (ref, 0));
2623 case COMPOUND_LITERAL_EXPR:
2633 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2634 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2638 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2645 /* Return nonzero if REF is an lvalue valid for this language;
2646 otherwise, print an error message and return zero. */
2649 lvalue_or_else (tree ref, const char *msgid)
2651 int win = lvalue_p (ref);
2654 error ("%s", msgid);
2660 /* Warn about storing in something that is `const'. */
2663 readonly_error (tree arg, const char *msgid)
2665 if (TREE_CODE (arg) == COMPONENT_REF)
2667 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2668 readonly_error (TREE_OPERAND (arg, 0), msgid);
2670 error ("%s of read-only member `%s'", _(msgid),
2671 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (arg, 1))));
2673 else if (TREE_CODE (arg) == VAR_DECL)
2674 error ("%s of read-only variable `%s'", _(msgid),
2675 IDENTIFIER_POINTER (DECL_NAME (arg)));
2677 error ("%s of read-only location", _(msgid));
2680 /* Mark EXP saying that we need to be able to take the
2681 address of it; it should not be allocated in a register.
2682 Returns true if successful. */
2685 c_mark_addressable (tree exp)
2690 switch (TREE_CODE (x))
2693 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2695 error ("cannot take address of bit-field `%s'",
2696 IDENTIFIER_POINTER (DECL_NAME (TREE_OPERAND (x, 1))));
2700 /* ... fall through ... */
2706 x = TREE_OPERAND (x, 0);
2709 case COMPOUND_LITERAL_EXPR:
2711 TREE_ADDRESSABLE (x) = 1;
2718 if (C_DECL_REGISTER (x)
2719 && DECL_NONLOCAL (x))
2721 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2723 error ("global register variable `%s' used in nested function",
2724 IDENTIFIER_POINTER (DECL_NAME (x)));
2727 pedwarn ("register variable `%s' used in nested function",
2728 IDENTIFIER_POINTER (DECL_NAME (x)));
2730 else if (C_DECL_REGISTER (x))
2732 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2734 error ("address of global register variable `%s' requested",
2735 IDENTIFIER_POINTER (DECL_NAME (x)));
2739 pedwarn ("address of register variable `%s' requested",
2740 IDENTIFIER_POINTER (DECL_NAME (x)));
2742 put_var_into_stack (x, /*rescan=*/true);
2746 TREE_ADDRESSABLE (x) = 1;
2753 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2756 build_conditional_expr (tree ifexp, tree op1, tree op2)
2760 enum tree_code code1;
2761 enum tree_code code2;
2762 tree result_type = NULL;
2763 tree orig_op1 = op1, orig_op2 = op2;
2765 ifexp = lang_hooks.truthvalue_conversion (default_conversion (ifexp));
2767 /* Promote both alternatives. */
2769 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2770 op1 = default_conversion (op1);
2771 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2772 op2 = default_conversion (op2);
2774 if (TREE_CODE (ifexp) == ERROR_MARK
2775 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2776 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2777 return error_mark_node;
2779 type1 = TREE_TYPE (op1);
2780 code1 = TREE_CODE (type1);
2781 type2 = TREE_TYPE (op2);
2782 code2 = TREE_CODE (type2);
2784 /* C90 does not permit non-lvalue arrays in conditional expressions.
2785 In C99 they will be pointers by now. */
2786 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2788 error ("non-lvalue array in conditional expression");
2789 return error_mark_node;
2792 /* Quickly detect the usual case where op1 and op2 have the same type
2794 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
2797 result_type = type1;
2799 result_type = TYPE_MAIN_VARIANT (type1);
2801 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
2802 || code1 == COMPLEX_TYPE)
2803 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
2804 || code2 == COMPLEX_TYPE))
2806 result_type = common_type (type1, type2);
2808 /* If -Wsign-compare, warn here if type1 and type2 have
2809 different signedness. We'll promote the signed to unsigned
2810 and later code won't know it used to be different.
2811 Do this check on the original types, so that explicit casts
2812 will be considered, but default promotions won't. */
2813 if (warn_sign_compare && !skip_evaluation)
2815 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
2816 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
2818 if (unsigned_op1 ^ unsigned_op2)
2820 /* Do not warn if the result type is signed, since the
2821 signed type will only be chosen if it can represent
2822 all the values of the unsigned type. */
2823 if (! TYPE_UNSIGNED (result_type))
2825 /* Do not warn if the signed quantity is an unsuffixed
2826 integer literal (or some static constant expression
2827 involving such literals) and it is non-negative. */
2828 else if ((unsigned_op2 && c_tree_expr_nonnegative_p (op1))
2829 || (unsigned_op1 && c_tree_expr_nonnegative_p (op2)))
2832 warning ("signed and unsigned type in conditional expression");
2836 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
2838 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
2839 pedwarn ("ISO C forbids conditional expr with only one void side");
2840 result_type = void_type_node;
2842 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
2844 if (comp_target_types (type1, type2, 1))
2845 result_type = common_pointer_type (type1, type2);
2846 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
2847 && TREE_CODE (orig_op1) != NOP_EXPR)
2848 result_type = qualify_type (type2, type1);
2849 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
2850 && TREE_CODE (orig_op2) != NOP_EXPR)
2851 result_type = qualify_type (type1, type2);
2852 else if (VOID_TYPE_P (TREE_TYPE (type1)))
2854 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
2855 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
2856 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
2857 TREE_TYPE (type2)));
2859 else if (VOID_TYPE_P (TREE_TYPE (type2)))
2861 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
2862 pedwarn ("ISO C forbids conditional expr between `void *' and function pointer");
2863 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
2864 TREE_TYPE (type1)));
2868 pedwarn ("pointer type mismatch in conditional expression");
2869 result_type = build_pointer_type (void_type_node);
2872 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
2874 if (! integer_zerop (op2))
2875 pedwarn ("pointer/integer type mismatch in conditional expression");
2878 op2 = null_pointer_node;
2880 result_type = type1;
2882 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
2884 if (!integer_zerop (op1))
2885 pedwarn ("pointer/integer type mismatch in conditional expression");
2888 op1 = null_pointer_node;
2890 result_type = type2;
2895 if (flag_cond_mismatch)
2896 result_type = void_type_node;
2899 error ("type mismatch in conditional expression");
2900 return error_mark_node;
2904 /* Merge const and volatile flags of the incoming types. */
2906 = build_type_variant (result_type,
2907 TREE_READONLY (op1) || TREE_READONLY (op2),
2908 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
2910 if (result_type != TREE_TYPE (op1))
2911 op1 = convert_and_check (result_type, op1);
2912 if (result_type != TREE_TYPE (op2))
2913 op2 = convert_and_check (result_type, op2);
2915 if (TREE_CODE (ifexp) == INTEGER_CST)
2916 return non_lvalue (integer_zerop (ifexp) ? op2 : op1);
2918 return fold (build (COND_EXPR, result_type, ifexp, op1, op2));
2921 /* Given a list of expressions, return a compound expression
2922 that performs them all and returns the value of the last of them. */
2925 build_compound_expr (tree list)
2927 return internal_build_compound_expr (list, TRUE);
2931 internal_build_compound_expr (tree list, int first_p)
2935 if (TREE_CHAIN (list) == 0)
2937 /* Convert arrays and functions to pointers when there
2938 really is a comma operator. */
2941 = default_function_array_conversion (TREE_VALUE (list));
2943 /* Don't let (0, 0) be null pointer constant. */
2944 if (!first_p && integer_zerop (TREE_VALUE (list)))
2945 return non_lvalue (TREE_VALUE (list));
2946 return TREE_VALUE (list);
2949 rest = internal_build_compound_expr (TREE_CHAIN (list), FALSE);
2951 if (! TREE_SIDE_EFFECTS (TREE_VALUE (list)))
2953 /* The left-hand operand of a comma expression is like an expression
2954 statement: with -Wextra or -Wunused, we should warn if it doesn't have
2955 any side-effects, unless it was explicitly cast to (void). */
2956 if (warn_unused_value
2957 && ! (TREE_CODE (TREE_VALUE (list)) == CONVERT_EXPR
2958 && VOID_TYPE_P (TREE_TYPE (TREE_VALUE (list)))))
2959 warning ("left-hand operand of comma expression has no effect");
2962 /* With -Wunused, we should also warn if the left-hand operand does have
2963 side-effects, but computes a value which is not used. For example, in
2964 `foo() + bar(), baz()' the result of the `+' operator is not used,
2965 so we should issue a warning. */
2966 else if (warn_unused_value)
2967 warn_if_unused_value (TREE_VALUE (list));
2969 return build (COMPOUND_EXPR, TREE_TYPE (rest), TREE_VALUE (list), rest);
2972 /* Build an expression representing a cast to type TYPE of expression EXPR. */
2975 build_c_cast (tree type, tree expr)
2979 if (type == error_mark_node || expr == error_mark_node)
2980 return error_mark_node;
2982 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
2983 only in <protocol> qualifications. But when constructing cast expressions,
2984 the protocols do matter and must be kept around. */
2985 if (!c_dialect_objc () || !objc_is_object_ptr (type))
2986 type = TYPE_MAIN_VARIANT (type);
2988 if (TREE_CODE (type) == ARRAY_TYPE)
2990 error ("cast specifies array type");
2991 return error_mark_node;
2994 if (TREE_CODE (type) == FUNCTION_TYPE)
2996 error ("cast specifies function type");
2997 return error_mark_node;
3000 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3004 if (TREE_CODE (type) == RECORD_TYPE
3005 || TREE_CODE (type) == UNION_TYPE)
3006 pedwarn ("ISO C forbids casting nonscalar to the same type");
3009 else if (TREE_CODE (type) == UNION_TYPE)
3012 value = default_function_array_conversion (value);
3014 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3015 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3016 TYPE_MAIN_VARIANT (TREE_TYPE (value)), COMPARE_STRICT))
3024 pedwarn ("ISO C forbids casts to union type");
3025 t = digest_init (type,
3026 build_constructor (type,
3027 build_tree_list (field, value)),
3029 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3030 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3033 error ("cast to union type from type not present in union");
3034 return error_mark_node;
3040 /* If casting to void, avoid the error that would come
3041 from default_conversion in the case of a non-lvalue array. */
3042 if (type == void_type_node)
3043 return build1 (CONVERT_EXPR, type, value);
3045 /* Convert functions and arrays to pointers,
3046 but don't convert any other types. */
3047 value = default_function_array_conversion (value);
3048 otype = TREE_TYPE (value);
3050 /* Optionally warn about potentially worrisome casts. */
3053 && TREE_CODE (type) == POINTER_TYPE
3054 && TREE_CODE (otype) == POINTER_TYPE)
3056 tree in_type = type;
3057 tree in_otype = otype;
3061 /* Check that the qualifiers on IN_TYPE are a superset of
3062 the qualifiers of IN_OTYPE. The outermost level of
3063 POINTER_TYPE nodes is uninteresting and we stop as soon
3064 as we hit a non-POINTER_TYPE node on either type. */
3067 in_otype = TREE_TYPE (in_otype);
3068 in_type = TREE_TYPE (in_type);
3070 /* GNU C allows cv-qualified function types. 'const'
3071 means the function is very pure, 'volatile' means it
3072 can't return. We need to warn when such qualifiers
3073 are added, not when they're taken away. */
3074 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3075 && TREE_CODE (in_type) == FUNCTION_TYPE)
3076 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3078 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3080 while (TREE_CODE (in_type) == POINTER_TYPE
3081 && TREE_CODE (in_otype) == POINTER_TYPE);
3084 warning ("cast adds new qualifiers to function type");
3087 /* There are qualifiers present in IN_OTYPE that are not
3088 present in IN_TYPE. */
3089 warning ("cast discards qualifiers from pointer target type");
3092 /* Warn about possible alignment problems. */
3093 if (STRICT_ALIGNMENT && warn_cast_align
3094 && TREE_CODE (type) == POINTER_TYPE
3095 && TREE_CODE (otype) == POINTER_TYPE
3096 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3097 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3098 /* Don't warn about opaque types, where the actual alignment
3099 restriction is unknown. */
3100 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3101 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3102 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3103 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3104 warning ("cast increases required alignment of target type");
3106 if (TREE_CODE (type) == INTEGER_TYPE
3107 && TREE_CODE (otype) == POINTER_TYPE
3108 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3109 && !TREE_CONSTANT (value))
3110 warning ("cast from pointer to integer of different size");
3112 if (warn_bad_function_cast
3113 && TREE_CODE (value) == CALL_EXPR
3114 && TREE_CODE (type) != TREE_CODE (otype))
3115 warning ("cast does not match function type");
3117 if (TREE_CODE (type) == POINTER_TYPE
3118 && TREE_CODE (otype) == INTEGER_TYPE
3119 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3120 /* Don't warn about converting any constant. */
3121 && !TREE_CONSTANT (value))
3122 warning ("cast to pointer from integer of different size");
3124 if (TREE_CODE (type) == POINTER_TYPE
3125 && TREE_CODE (otype) == POINTER_TYPE
3126 && TREE_CODE (expr) == ADDR_EXPR
3127 && DECL_P (TREE_OPERAND (expr, 0))
3128 && flag_strict_aliasing && warn_strict_aliasing
3129 && !VOID_TYPE_P (TREE_TYPE (type)))
3131 /* Casting the address of a decl to non void pointer. Warn
3132 if the cast breaks type based aliasing. */
3133 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3134 warning ("type-punning to incomplete type might break strict-aliasing rules");
3137 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3138 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3140 if (!alias_sets_conflict_p (set1, set2))
3141 warning ("dereferencing type-punned pointer will break strict-aliasing rules");
3142 else if (warn_strict_aliasing > 1
3143 && !alias_sets_might_conflict_p (set1, set2))
3144 warning ("dereferencing type-punned pointer might break strict-aliasing rules");
3148 /* If pedantic, warn for conversions between function and object
3149 pointer types, except for converting a null pointer constant
3150 to function pointer type. */
3152 && TREE_CODE (type) == POINTER_TYPE
3153 && TREE_CODE (otype) == POINTER_TYPE
3154 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3155 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3156 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3159 && TREE_CODE (type) == POINTER_TYPE
3160 && TREE_CODE (otype) == POINTER_TYPE
3161 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3162 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3163 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3164 && TREE_CODE (expr) != NOP_EXPR))
3165 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3168 /* Replace a nonvolatile const static variable with its value. */
3169 if (optimize && TREE_CODE (value) == VAR_DECL)
3170 value = decl_constant_value (value);
3171 value = convert (type, value);
3173 /* Ignore any integer overflow caused by the cast. */
3174 if (TREE_CODE (value) == INTEGER_CST)
3176 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3178 if (TREE_CODE_CLASS (TREE_CODE (ovalue)) == 'c')
3179 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3183 /* Don't let (void *) (FOO *) 0 be a null pointer constant. */
3184 if (TREE_CODE (value) == INTEGER_CST
3185 && TREE_CODE (expr) == INTEGER_CST
3186 && TREE_CODE (TREE_TYPE (expr)) != INTEGER_TYPE)
3187 value = non_lvalue (value);
3189 /* Don't let a cast be an lvalue. */
3191 value = non_lvalue (value);
3196 /* Interpret a cast of expression EXPR to type TYPE. */
3198 c_cast_expr (tree type, tree expr)
3200 int saved_wsp = warn_strict_prototypes;
3202 /* This avoids warnings about unprototyped casts on
3203 integers. E.g. "#define SIG_DFL (void(*)())0". */
3204 if (TREE_CODE (expr) == INTEGER_CST)
3205 warn_strict_prototypes = 0;
3206 type = groktypename (type);
3207 warn_strict_prototypes = saved_wsp;
3209 return build_c_cast (type, expr);
3213 /* Build an assignment expression of lvalue LHS from value RHS.
3214 MODIFYCODE is the code for a binary operator that we use
3215 to combine the old value of LHS with RHS to get the new value.
3216 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3219 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3223 tree lhstype = TREE_TYPE (lhs);
3224 tree olhstype = lhstype;
3226 /* Types that aren't fully specified cannot be used in assignments. */
3227 lhs = require_complete_type (lhs);
3229 /* Avoid duplicate error messages from operands that had errors. */
3230 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3231 return error_mark_node;
3233 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3234 /* Do not use STRIP_NOPS here. We do not want an enumerator
3235 whose value is 0 to count as a null pointer constant. */
3236 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3237 rhs = TREE_OPERAND (rhs, 0);
3241 /* If a binary op has been requested, combine the old LHS value with the RHS
3242 producing the value we should actually store into the LHS. */
3244 if (modifycode != NOP_EXPR)
3246 lhs = stabilize_reference (lhs);
3247 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3250 if (!lvalue_or_else (lhs, "invalid lvalue in assignment"))
3251 return error_mark_node;
3253 /* Warn about storing in something that is `const'. */
3255 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3256 || ((TREE_CODE (lhstype) == RECORD_TYPE
3257 || TREE_CODE (lhstype) == UNION_TYPE)
3258 && C_TYPE_FIELDS_READONLY (lhstype)))
3259 readonly_error (lhs, "assignment");
3261 /* If storing into a structure or union member,
3262 it has probably been given type `int'.
3263 Compute the type that would go with
3264 the actual amount of storage the member occupies. */
3266 if (TREE_CODE (lhs) == COMPONENT_REF
3267 && (TREE_CODE (lhstype) == INTEGER_TYPE
3268 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3269 || TREE_CODE (lhstype) == REAL_TYPE
3270 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3271 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3273 /* If storing in a field that is in actuality a short or narrower than one,
3274 we must store in the field in its actual type. */
3276 if (lhstype != TREE_TYPE (lhs))
3278 lhs = copy_node (lhs);
3279 TREE_TYPE (lhs) = lhstype;
3282 /* Convert new value to destination type. */
3284 newrhs = convert_for_assignment (lhstype, newrhs, _("assignment"),
3285 NULL_TREE, NULL_TREE, 0);
3286 if (TREE_CODE (newrhs) == ERROR_MARK)
3287 return error_mark_node;
3291 result = build (MODIFY_EXPR, lhstype, lhs, newrhs);
3292 TREE_SIDE_EFFECTS (result) = 1;
3294 /* If we got the LHS in a different type for storing in,
3295 convert the result back to the nominal type of LHS
3296 so that the value we return always has the same type
3297 as the LHS argument. */
3299 if (olhstype == TREE_TYPE (result))
3301 return convert_for_assignment (olhstype, result, _("assignment"),
3302 NULL_TREE, NULL_TREE, 0);
3305 /* Convert value RHS to type TYPE as preparation for an assignment
3306 to an lvalue of type TYPE.
3307 The real work of conversion is done by `convert'.
3308 The purpose of this function is to generate error messages
3309 for assignments that are not allowed in C.
3310 ERRTYPE is a string to use in error messages:
3311 "assignment", "return", etc. If it is null, this is parameter passing
3312 for a function call (and different error messages are output).
3314 FUNNAME is the name of the function being called,
3315 as an IDENTIFIER_NODE, or null.
3316 PARMNUM is the number of the argument, for printing in error messages. */
3319 convert_for_assignment (tree type, tree rhs, const char *errtype,
3320 tree fundecl, tree funname, int parmnum)
3322 enum tree_code codel = TREE_CODE (type);
3324 enum tree_code coder;
3326 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3327 /* Do not use STRIP_NOPS here. We do not want an enumerator
3328 whose value is 0 to count as a null pointer constant. */
3329 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
3330 rhs = TREE_OPERAND (rhs, 0);
3332 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3333 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3334 rhs = default_conversion (rhs);
3335 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3336 rhs = decl_constant_value_for_broken_optimization (rhs);
3338 rhstype = TREE_TYPE (rhs);
3339 coder = TREE_CODE (rhstype);
3341 if (coder == ERROR_MARK)
3342 return error_mark_node;
3344 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3346 overflow_warning (rhs);
3347 /* Check for Objective-C protocols. This will automatically
3348 issue a warning if there are protocol violations. No need to
3349 use the return value. */
3350 if (c_dialect_objc ())
3351 objc_comptypes (type, rhstype, 0);
3355 if (coder == VOID_TYPE)
3357 error ("void value not ignored as it ought to be");
3358 return error_mark_node;
3360 /* A type converts to a reference to it.
3361 This code doesn't fully support references, it's just for the
3362 special case of va_start and va_copy. */
3363 if (codel == REFERENCE_TYPE
3364 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs), COMPARE_STRICT) == 1)
3366 if (!lvalue_p (rhs))
3368 error ("cannot pass rvalue to reference parameter");
3369 return error_mark_node;
3371 if (!c_mark_addressable (rhs))
3372 return error_mark_node;
3373 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3375 /* We already know that these two types are compatible, but they
3376 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3377 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3378 likely to be va_list, a typedef to __builtin_va_list, which
3379 is different enough that it will cause problems later. */
3380 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3381 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3383 rhs = build1 (NOP_EXPR, type, rhs);
3386 /* Some types can interconvert without explicit casts. */
3387 else if (codel == VECTOR_TYPE
3388 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3389 return convert (type, rhs);
3390 /* Arithmetic types all interconvert, and enum is treated like int. */
3391 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3392 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3393 || codel == BOOLEAN_TYPE)
3394 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3395 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3396 || coder == BOOLEAN_TYPE))
3397 return convert_and_check (type, rhs);
3399 /* Conversion to a transparent union from its member types.
3400 This applies only to function arguments. */
3401 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) && ! errtype)
3404 tree marginal_memb_type = 0;
3406 for (memb_types = TYPE_FIELDS (type); memb_types;
3407 memb_types = TREE_CHAIN (memb_types))
3409 tree memb_type = TREE_TYPE (memb_types);
3411 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3412 TYPE_MAIN_VARIANT (rhstype), COMPARE_STRICT))
3415 if (TREE_CODE (memb_type) != POINTER_TYPE)
3418 if (coder == POINTER_TYPE)
3420 tree ttl = TREE_TYPE (memb_type);
3421 tree ttr = TREE_TYPE (rhstype);
3423 /* Any non-function converts to a [const][volatile] void *
3424 and vice versa; otherwise, targets must be the same.
3425 Meanwhile, the lhs target must have all the qualifiers of
3427 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3428 || comp_target_types (memb_type, rhstype, 0))
3430 /* If this type won't generate any warnings, use it. */
3431 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3432 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3433 && TREE_CODE (ttl) == FUNCTION_TYPE)
3434 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3435 == TYPE_QUALS (ttr))
3436 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3437 == TYPE_QUALS (ttl))))
3440 /* Keep looking for a better type, but remember this one. */
3441 if (! marginal_memb_type)
3442 marginal_memb_type = memb_type;
3446 /* Can convert integer zero to any pointer type. */
3447 if (integer_zerop (rhs)
3448 || (TREE_CODE (rhs) == NOP_EXPR
3449 && integer_zerop (TREE_OPERAND (rhs, 0))))
3451 rhs = null_pointer_node;
3456 if (memb_types || marginal_memb_type)
3460 /* We have only a marginally acceptable member type;
3461 it needs a warning. */
3462 tree ttl = TREE_TYPE (marginal_memb_type);
3463 tree ttr = TREE_TYPE (rhstype);
3465 /* Const and volatile mean something different for function
3466 types, so the usual warnings are not appropriate. */
3467 if (TREE_CODE (ttr) == FUNCTION_TYPE
3468 && TREE_CODE (ttl) == FUNCTION_TYPE)
3470 /* Because const and volatile on functions are
3471 restrictions that say the function will not do
3472 certain things, it is okay to use a const or volatile
3473 function where an ordinary one is wanted, but not
3475 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3476 warn_for_assignment ("%s makes qualified function pointer from unqualified",
3477 errtype, funname, parmnum);
3479 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3480 warn_for_assignment ("%s discards qualifiers from pointer target type",
3485 if (pedantic && ! DECL_IN_SYSTEM_HEADER (fundecl))
3486 pedwarn ("ISO C prohibits argument conversion to union type");
3488 return build1 (NOP_EXPR, type, rhs);
3492 /* Conversions among pointers */
3493 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3494 && (coder == codel))
3496 tree ttl = TREE_TYPE (type);
3497 tree ttr = TREE_TYPE (rhstype);
3498 bool is_opaque_pointer;
3499 int target_cmp = 0; /* Cache comp_target_types () result. */
3501 /* Opaque pointers are treated like void pointers. */
3502 is_opaque_pointer = (targetm.vector_opaque_p (type)
3503 || targetm.vector_opaque_p (rhstype))
3504 && TREE_CODE (ttl) == VECTOR_TYPE
3505 && TREE_CODE (ttr) == VECTOR_TYPE;
3507 /* Any non-function converts to a [const][volatile] void *
3508 and vice versa; otherwise, targets must be the same.
3509 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3510 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3511 || (target_cmp = comp_target_types (type, rhstype, 0))
3512 || is_opaque_pointer
3513 || (c_common_unsigned_type (TYPE_MAIN_VARIANT (ttl))
3514 == c_common_unsigned_type (TYPE_MAIN_VARIANT (ttr))))
3517 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3520 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3521 which are not ANSI null ptr constants. */
3522 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3523 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3524 warn_for_assignment ("ISO C forbids %s between function pointer and `void *'",
3525 errtype, funname, parmnum);
3526 /* Const and volatile mean something different for function types,
3527 so the usual warnings are not appropriate. */
3528 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3529 && TREE_CODE (ttl) != FUNCTION_TYPE)
3531 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3532 warn_for_assignment ("%s discards qualifiers from pointer target type",
3533 errtype, funname, parmnum);
3534 /* If this is not a case of ignoring a mismatch in signedness,
3536 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3539 /* If there is a mismatch, do warn. */
3541 warn_for_assignment ("pointer targets in %s differ in signedness",
3542 errtype, funname, parmnum);
3544 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3545 && TREE_CODE (ttr) == FUNCTION_TYPE)
3547 /* Because const and volatile on functions are restrictions
3548 that say the function will not do certain things,
3549 it is okay to use a const or volatile function
3550 where an ordinary one is wanted, but not vice-versa. */
3551 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3552 warn_for_assignment ("%s makes qualified function pointer from unqualified",
3553 errtype, funname, parmnum);
3557 warn_for_assignment ("%s from incompatible pointer type",
3558 errtype, funname, parmnum);
3559 return convert (type, rhs);
3561 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3563 error ("invalid use of non-lvalue array");
3564 return error_mark_node;
3566 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3568 /* An explicit constant 0 can convert to a pointer,
3569 or one that results from arithmetic, even including
3570 a cast to integer type. */
3571 if (! (TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3573 ! (TREE_CODE (rhs) == NOP_EXPR
3574 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3575 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3576 && integer_zerop (TREE_OPERAND (rhs, 0))))
3577 warn_for_assignment ("%s makes pointer from integer without a cast",
3578 errtype, funname, parmnum);
3580 return convert (type, rhs);
3582 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3584 warn_for_assignment ("%s makes integer from pointer without a cast",
3585 errtype, funname, parmnum);
3586 return convert (type, rhs);
3588 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3589 return convert (type, rhs);
3595 tree selector = objc_message_selector ();
3597 if (selector && parmnum > 2)
3598 error ("incompatible type for argument %d of `%s'",
3599 parmnum - 2, IDENTIFIER_POINTER (selector));
3601 error ("incompatible type for argument %d of `%s'",
3602 parmnum, IDENTIFIER_POINTER (funname));
3605 error ("incompatible type for argument %d of indirect function call",
3609 error ("incompatible types in %s", errtype);
3611 return error_mark_node;
3614 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3615 is used for error and waring reporting and indicates which argument
3616 is being processed. */
3619 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3623 /* If FN was prototyped, the value has been converted already
3624 in convert_arguments. */
3625 if (! value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3628 type = TREE_TYPE (parm);
3629 ret = convert_for_assignment (type, value,
3630 (char *) 0 /* arg passing */, fn,
3631 DECL_NAME (fn), argnum);
3632 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3633 && INTEGRAL_TYPE_P (type)
3634 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3635 ret = default_conversion (ret);
3639 /* Print a warning using MSGID.
3640 It gets OPNAME as its one parameter.
3641 if OPNAME is null and ARGNUM is 0, it is replaced by "passing arg of `FUNCTION'".
3642 Otherwise if OPNAME is null, it is replaced by "passing arg ARGNUM of `FUNCTION'".
3643 FUNCTION and ARGNUM are handled specially if we are building an
3644 Objective-C selector. */
3647 warn_for_assignment (const char *msgid, const char *opname, tree function,
3652 tree selector = objc_message_selector ();
3655 if (selector && argnum > 2)
3657 function = selector;
3664 /* Function name is known; supply it. */
3665 const char *const argstring = _("passing arg of `%s'");
3666 new_opname = alloca (IDENTIFIER_LENGTH (function)
3667 + strlen (argstring) + 1 + 1);
3668 sprintf (new_opname, argstring,
3669 IDENTIFIER_POINTER (function));
3673 /* Function name unknown (call through ptr). */
3674 const char *const argnofun = _("passing arg of pointer to function");
3675 new_opname = alloca (strlen (argnofun) + 1 + 1);
3676 sprintf (new_opname, argnofun);
3681 /* Function name is known; supply it. */
3682 const char *const argstring = _("passing arg %d of `%s'");
3683 new_opname = alloca (IDENTIFIER_LENGTH (function)
3684 + strlen (argstring) + 1 + 25 /*%d*/ + 1);
3685 sprintf (new_opname, argstring, argnum,
3686 IDENTIFIER_POINTER (function));
3690 /* Function name unknown (call through ptr); just give arg number. */
3691 const char *const argnofun = _("passing arg %d of pointer to function");
3692 new_opname = alloca (strlen (argnofun) + 1 + 25 /*%d*/ + 1);
3693 sprintf (new_opname, argnofun, argnum);
3695 opname = new_opname;
3697 pedwarn (msgid, opname);
3700 /* If VALUE is a compound expr all of whose expressions are constant, then
3701 return its value. Otherwise, return error_mark_node.
3703 This is for handling COMPOUND_EXPRs as initializer elements
3704 which is allowed with a warning when -pedantic is specified. */
3707 valid_compound_expr_initializer (tree value, tree endtype)
3709 if (TREE_CODE (value) == COMPOUND_EXPR)
3711 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3713 return error_mark_node;
3714 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3717 else if (! TREE_CONSTANT (value)
3718 && ! initializer_constant_valid_p (value, endtype))
3719 return error_mark_node;
3724 /* Perform appropriate conversions on the initial value of a variable,
3725 store it in the declaration DECL,
3726 and print any error messages that are appropriate.
3727 If the init is invalid, store an ERROR_MARK. */
3730 store_init_value (tree decl, tree init)
3734 /* If variable's type was invalidly declared, just ignore it. */
3736 type = TREE_TYPE (decl);
3737 if (TREE_CODE (type) == ERROR_MARK)
3740 /* Digest the specified initializer into an expression. */
3742 value = digest_init (type, init, TREE_STATIC (decl));
3744 /* Store the expression if valid; else report error. */
3746 if (warn_traditional && !in_system_header
3747 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && ! TREE_STATIC (decl))
3748 warning ("traditional C rejects automatic aggregate initialization");
3750 DECL_INITIAL (decl) = value;
3752 /* ANSI wants warnings about out-of-range constant initializers. */
3753 STRIP_TYPE_NOPS (value);
3754 constant_expression_warning (value);
3756 /* Check if we need to set array size from compound literal size. */
3757 if (TREE_CODE (type) == ARRAY_TYPE
3758 && TYPE_DOMAIN (type) == 0
3759 && value != error_mark_node)
3761 tree inside_init = init;
3763 if (TREE_CODE (init) == NON_LVALUE_EXPR)
3764 inside_init = TREE_OPERAND (init, 0);
3765 inside_init = fold (inside_init);
3767 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
3769 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
3771 if (TYPE_DOMAIN (TREE_TYPE (decl)))
3773 /* For int foo[] = (int [3]){1}; we need to set array size
3774 now since later on array initializer will be just the
3775 brace enclosed list of the compound literal. */
3776 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
3778 layout_decl (decl, 0);
3784 /* Methods for storing and printing names for error messages. */
3786 /* Implement a spelling stack that allows components of a name to be pushed
3787 and popped. Each element on the stack is this structure. */
3799 #define SPELLING_STRING 1
3800 #define SPELLING_MEMBER 2
3801 #define SPELLING_BOUNDS 3
3803 static struct spelling *spelling; /* Next stack element (unused). */
3804 static struct spelling *spelling_base; /* Spelling stack base. */
3805 static int spelling_size; /* Size of the spelling stack. */
3807 /* Macros to save and restore the spelling stack around push_... functions.
3808 Alternative to SAVE_SPELLING_STACK. */
3810 #define SPELLING_DEPTH() (spelling - spelling_base)
3811 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
3813 /* Push an element on the spelling stack with type KIND and assign VALUE
3816 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
3818 int depth = SPELLING_DEPTH (); \
3820 if (depth >= spelling_size) \
3822 spelling_size += 10; \
3823 if (spelling_base == 0) \
3824 spelling_base = xmalloc (spelling_size * sizeof (struct spelling)); \
3826 spelling_base = xrealloc (spelling_base, \
3827 spelling_size * sizeof (struct spelling)); \
3828 RESTORE_SPELLING_DEPTH (depth); \
3831 spelling->kind = (KIND); \
3832 spelling->MEMBER = (VALUE); \
3836 /* Push STRING on the stack. Printed literally. */
3839 push_string (const char *string)
3841 PUSH_SPELLING (SPELLING_STRING, string, u.s);
3844 /* Push a member name on the stack. Printed as '.' STRING. */
3847 push_member_name (tree decl)
3849 const char *const string
3850 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
3851 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
3854 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
3857 push_array_bounds (int bounds)
3859 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
3862 /* Compute the maximum size in bytes of the printed spelling. */
3865 spelling_length (void)
3870 for (p = spelling_base; p < spelling; p++)
3872 if (p->kind == SPELLING_BOUNDS)
3875 size += strlen (p->u.s) + 1;
3881 /* Print the spelling to BUFFER and return it. */
3884 print_spelling (char *buffer)
3889 for (p = spelling_base; p < spelling; p++)
3890 if (p->kind == SPELLING_BOUNDS)
3892 sprintf (d, "[%d]", p->u.i);
3898 if (p->kind == SPELLING_MEMBER)
3900 for (s = p->u.s; (*d = *s++); d++)
3907 /* Issue an error message for a bad initializer component.
3908 MSGID identifies the message.
3909 The component name is taken from the spelling stack. */
3912 error_init (const char *msgid)
3916 error ("%s", _(msgid));
3917 ofwhat = print_spelling (alloca (spelling_length () + 1));
3919 error ("(near initialization for `%s')", ofwhat);
3922 /* Issue a pedantic warning for a bad initializer component.
3923 MSGID identifies the message.
3924 The component name is taken from the spelling stack. */
3927 pedwarn_init (const char *msgid)
3931 pedwarn ("%s", _(msgid));
3932 ofwhat = print_spelling (alloca (spelling_length () + 1));
3934 pedwarn ("(near initialization for `%s')", ofwhat);
3937 /* Issue a warning for a bad initializer component.
3938 MSGID identifies the message.
3939 The component name is taken from the spelling stack. */
3942 warning_init (const char *msgid)
3946 warning ("%s", _(msgid));
3947 ofwhat = print_spelling (alloca (spelling_length () + 1));
3949 warning ("(near initialization for `%s')", ofwhat);
3952 /* Digest the parser output INIT as an initializer for type TYPE.
3953 Return a C expression of type TYPE to represent the initial value.
3955 REQUIRE_CONSTANT requests an error if non-constant initializers or
3956 elements are seen. */
3959 digest_init (tree type, tree init, int require_constant)
3961 enum tree_code code = TREE_CODE (type);
3962 tree inside_init = init;
3964 if (type == error_mark_node
3965 || init == error_mark_node
3966 || TREE_TYPE (init) == error_mark_node)
3967 return error_mark_node;
3969 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
3970 /* Do not use STRIP_NOPS here. We do not want an enumerator
3971 whose value is 0 to count as a null pointer constant. */
3972 if (TREE_CODE (init) == NON_LVALUE_EXPR)
3973 inside_init = TREE_OPERAND (init, 0);
3975 inside_init = fold (inside_init);
3977 /* Initialization of an array of chars from a string constant
3978 optionally enclosed in braces. */
3980 if (code == ARRAY_TYPE)
3982 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
3983 if ((typ1 == char_type_node
3984 || typ1 == signed_char_type_node
3985 || typ1 == unsigned_char_type_node
3986 || typ1 == unsigned_wchar_type_node
3987 || typ1 == signed_wchar_type_node)
3988 && ((inside_init && TREE_CODE (inside_init) == STRING_CST)))
3990 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
3991 TYPE_MAIN_VARIANT (type), COMPARE_STRICT))
3994 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
3996 && TYPE_PRECISION (typ1) == TYPE_PRECISION (char_type_node))
3998 error_init ("char-array initialized from wide string");
3999 return error_mark_node;
4001 if ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4003 && TYPE_PRECISION (typ1) != TYPE_PRECISION (char_type_node))
4005 error_init ("int-array initialized from non-wide string");
4006 return error_mark_node;
4009 TREE_TYPE (inside_init) = type;
4010 if (TYPE_DOMAIN (type) != 0
4011 && TYPE_SIZE (type) != 0
4012 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4013 /* Subtract 1 (or sizeof (wchar_t))
4014 because it's ok to ignore the terminating null char
4015 that is counted in the length of the constant. */
4016 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4017 TREE_STRING_LENGTH (inside_init)
4018 - ((TYPE_PRECISION (typ1)
4019 != TYPE_PRECISION (char_type_node))
4020 ? (TYPE_PRECISION (wchar_type_node)
4023 pedwarn_init ("initializer-string for array of chars is too long");
4029 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4030 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4031 below and handle as a constructor. */
4032 if (code == VECTOR_TYPE
4033 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4034 && TREE_CONSTANT (inside_init))
4036 if (TREE_CODE (inside_init) == VECTOR_CST
4037 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4038 TYPE_MAIN_VARIANT (type),
4042 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4045 /* Any type can be initialized
4046 from an expression of the same type, optionally with braces. */
4048 if (inside_init && TREE_TYPE (inside_init) != 0
4049 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4050 TYPE_MAIN_VARIANT (type), COMPARE_STRICT)
4051 || (code == ARRAY_TYPE
4052 && comptypes (TREE_TYPE (inside_init), type, COMPARE_STRICT))
4053 || (code == VECTOR_TYPE
4054 && comptypes (TREE_TYPE (inside_init), type, COMPARE_STRICT))
4055 || (code == POINTER_TYPE
4056 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4057 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4058 TREE_TYPE (type), COMPARE_STRICT))
4059 || (code == POINTER_TYPE
4060 && TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE
4061 && comptypes (TREE_TYPE (inside_init),
4062 TREE_TYPE (type), COMPARE_STRICT))))
4064 if (code == POINTER_TYPE)
4066 inside_init = default_function_array_conversion (inside_init);
4068 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4070 error_init ("invalid use of non-lvalue array");
4071 return error_mark_node;
4075 if (code == VECTOR_TYPE)
4076 /* Although the types are compatible, we may require a
4078 inside_init = convert (type, inside_init);
4080 if (require_constant && !flag_isoc99
4081 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4083 /* As an extension, allow initializing objects with static storage
4084 duration with compound literals (which are then treated just as
4085 the brace enclosed list they contain). */
4086 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4087 inside_init = DECL_INITIAL (decl);
4090 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4091 && TREE_CODE (inside_init) != CONSTRUCTOR)
4093 error_init ("array initialized from non-constant array expression");
4094 return error_mark_node;
4097 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4098 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4100 /* Compound expressions can only occur here if -pedantic or
4101 -pedantic-errors is specified. In the later case, we always want
4102 an error. In the former case, we simply want a warning. */
4103 if (require_constant && pedantic
4104 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4107 = valid_compound_expr_initializer (inside_init,
4108 TREE_TYPE (inside_init));
4109 if (inside_init == error_mark_node)
4110 error_init ("initializer element is not constant");
4112 pedwarn_init ("initializer element is not constant");
4113 if (flag_pedantic_errors)
4114 inside_init = error_mark_node;
4116 else if (require_constant
4117 && (!TREE_CONSTANT (inside_init)
4118 /* This test catches things like `7 / 0' which
4119 result in an expression for which TREE_CONSTANT
4120 is true, but which is not actually something
4121 that is a legal constant. We really should not
4122 be using this function, because it is a part of
4123 the back-end. Instead, the expression should
4124 already have been turned into ERROR_MARK_NODE. */
4125 || !initializer_constant_valid_p (inside_init,
4126 TREE_TYPE (inside_init))))
4128 error_init ("initializer element is not constant");
4129 inside_init = error_mark_node;
4135 /* Handle scalar types, including conversions. */
4137 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4138 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4139 || code == VECTOR_TYPE)
4141 /* Note that convert_for_assignment calls default_conversion
4142 for arrays and functions. We must not call it in the
4143 case where inside_init is a null pointer constant. */
4145 = convert_for_assignment (type, init, _("initialization"),
4146 NULL_TREE, NULL_TREE, 0);
4148 if (require_constant && ! TREE_CONSTANT (inside_init))
4150 error_init ("initializer element is not constant");
4151 inside_init = error_mark_node;
4153 else if (require_constant
4154 && initializer_constant_valid_p (inside_init, TREE_TYPE (inside_init)) == 0)
4156 error_init ("initializer element is not computable at load time");
4157 inside_init = error_mark_node;
4163 /* Come here only for records and arrays. */
4165 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4167 error_init ("variable-sized object may not be initialized");
4168 return error_mark_node;
4171 error_init ("invalid initializer");
4172 return error_mark_node;
4175 /* Handle initializers that use braces. */
4177 /* Type of object we are accumulating a constructor for.
4178 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4179 static tree constructor_type;
4181 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4183 static tree constructor_fields;
4185 /* For an ARRAY_TYPE, this is the specified index
4186 at which to store the next element we get. */
4187 static tree constructor_index;
4189 /* For an ARRAY_TYPE, this is the maximum index. */
4190 static tree constructor_max_index;
4192 /* For a RECORD_TYPE, this is the first field not yet written out. */
4193 static tree constructor_unfilled_fields;
4195 /* For an ARRAY_TYPE, this is the index of the first element
4196 not yet written out. */
4197 static tree constructor_unfilled_index;
4199 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4200 This is so we can generate gaps between fields, when appropriate. */
4201 static tree constructor_bit_index;
4203 /* If we are saving up the elements rather than allocating them,
4204 this is the list of elements so far (in reverse order,
4205 most recent first). */
4206 static tree constructor_elements;
4208 /* 1 if constructor should be incrementally stored into a constructor chain,
4209 0 if all the elements should be kept in AVL tree. */
4210 static int constructor_incremental;
4212 /* 1 if so far this constructor's elements are all compile-time constants. */
4213 static int constructor_constant;
4215 /* 1 if so far this constructor's elements are all valid address constants. */
4216 static int constructor_simple;
4218 /* 1 if this constructor is erroneous so far. */
4219 static int constructor_erroneous;
4221 /* Structure for managing pending initializer elements, organized as an
4226 struct init_node *left, *right;
4227 struct init_node *parent;
4233 /* Tree of pending elements at this constructor level.
4234 These are elements encountered out of order
4235 which belong at places we haven't reached yet in actually
4237 Will never hold tree nodes across GC runs. */
4238 static struct init_node *constructor_pending_elts;
4240 /* The SPELLING_DEPTH of this constructor. */
4241 static int constructor_depth;
4243 /* 0 if implicitly pushing constructor levels is allowed. */
4244 int constructor_no_implicit = 0; /* 0 for C; 1 for some other languages. */
4246 /* DECL node for which an initializer is being read.
4247 0 means we are reading a constructor expression
4248 such as (struct foo) {...}. */
4249 static tree constructor_decl;
4251 /* start_init saves the ASMSPEC arg here for really_start_incremental_init. */
4252 static const char *constructor_asmspec;
4254 /* Nonzero if this is an initializer for a top-level decl. */
4255 static int constructor_top_level;
4257 /* Nonzero if there were any member designators in this initializer. */
4258 static int constructor_designated;
4260 /* Nesting depth of designator list. */
4261 static int designator_depth;
4263 /* Nonzero if there were diagnosed errors in this designator list. */
4264 static int designator_errorneous;
4267 /* This stack has a level for each implicit or explicit level of
4268 structuring in the initializer, including the outermost one. It
4269 saves the values of most of the variables above. */
4271 struct constructor_range_stack;
4273 struct constructor_stack
4275 struct constructor_stack *next;
4280 tree unfilled_index;
4281 tree unfilled_fields;
4284 struct init_node *pending_elts;
4287 /* If nonzero, this value should replace the entire
4288 constructor at this level. */
4289 tree replacement_value;
4290 struct constructor_range_stack *range_stack;
4300 struct constructor_stack *constructor_stack;
4302 /* This stack represents designators from some range designator up to
4303 the last designator in the list. */
4305 struct constructor_range_stack
4307 struct constructor_range_stack *next, *prev;
4308 struct constructor_stack *stack;
4315 struct constructor_range_stack *constructor_range_stack;
4317 /* This stack records separate initializers that are nested.
4318 Nested initializers can't happen in ANSI C, but GNU C allows them
4319 in cases like { ... (struct foo) { ... } ... }. */
4321 struct initializer_stack
4323 struct initializer_stack *next;
4325 const char *asmspec;
4326 struct constructor_stack *constructor_stack;
4327 struct constructor_range_stack *constructor_range_stack;
4329 struct spelling *spelling;
4330 struct spelling *spelling_base;
4333 char require_constant_value;
4334 char require_constant_elements;
4337 struct initializer_stack *initializer_stack;
4339 /* Prepare to parse and output the initializer for variable DECL. */
4342 start_init (tree decl, tree asmspec_tree, int top_level)
4345 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4346 const char *asmspec = 0;
4349 asmspec = TREE_STRING_POINTER (asmspec_tree);
4351 p->decl = constructor_decl;
4352 p->asmspec = constructor_asmspec;
4353 p->require_constant_value = require_constant_value;
4354 p->require_constant_elements = require_constant_elements;
4355 p->constructor_stack = constructor_stack;
4356 p->constructor_range_stack = constructor_range_stack;
4357 p->elements = constructor_elements;
4358 p->spelling = spelling;
4359 p->spelling_base = spelling_base;
4360 p->spelling_size = spelling_size;
4361 p->top_level = constructor_top_level;
4362 p->next = initializer_stack;
4363 initializer_stack = p;
4365 constructor_decl = decl;
4366 constructor_asmspec = asmspec;
4367 constructor_designated = 0;
4368 constructor_top_level = top_level;
4372 require_constant_value = TREE_STATIC (decl);
4373 require_constant_elements
4374 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4375 /* For a scalar, you can always use any value to initialize,
4376 even within braces. */
4377 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4378 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4379 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4380 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4381 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4385 require_constant_value = 0;
4386 require_constant_elements = 0;
4387 locus = "(anonymous)";
4390 constructor_stack = 0;
4391 constructor_range_stack = 0;
4393 missing_braces_mentioned = 0;
4397 RESTORE_SPELLING_DEPTH (0);
4400 push_string (locus);
4406 struct initializer_stack *p = initializer_stack;
4408 /* Free the whole constructor stack of this initializer. */
4409 while (constructor_stack)
4411 struct constructor_stack *q = constructor_stack;
4412 constructor_stack = q->next;
4416 if (constructor_range_stack)
4419 /* Pop back to the data of the outer initializer (if any). */
4420 free (spelling_base);
4422 constructor_decl = p->decl;
4423 constructor_asmspec = p->asmspec;
4424 require_constant_value = p->require_constant_value;
4425 require_constant_elements = p->require_constant_elements;
4426 constructor_stack = p->constructor_stack;
4427 constructor_range_stack = p->constructor_range_stack;
4428 constructor_elements = p->elements;
4429 spelling = p->spelling;
4430 spelling_base = p->spelling_base;
4431 spelling_size = p->spelling_size;
4432 constructor_top_level = p->top_level;
4433 initializer_stack = p->next;
4437 /* Call here when we see the initializer is surrounded by braces.
4438 This is instead of a call to push_init_level;
4439 it is matched by a call to pop_init_level.
4441 TYPE is the type to initialize, for a constructor expression.
4442 For an initializer for a decl, TYPE is zero. */
4445 really_start_incremental_init (tree type)
4447 struct constructor_stack *p = xmalloc (sizeof (struct constructor_stack));
4450 type = TREE_TYPE (constructor_decl);
4452 if (targetm.vector_opaque_p (type))
4453 error ("opaque vector types cannot be initialized");
4455 p->type = constructor_type;
4456 p->fields = constructor_fields;
4457 p->index = constructor_index;
4458 p->max_index = constructor_max_index;
4459 p->unfilled_index = constructor_unfilled_index;
4460 p->unfilled_fields = constructor_unfilled_fields;
4461 p->bit_index = constructor_bit_index;
4462 p->elements = constructor_elements;
4463 p->constant = constructor_constant;
4464 p->simple = constructor_simple;
4465 p->erroneous = constructor_erroneous;
4466 p->pending_elts = constructor_pending_elts;
4467 p->depth = constructor_depth;
4468 p->replacement_value = 0;
4472 p->incremental = constructor_incremental;
4473 p->designated = constructor_designated;
4475 constructor_stack = p;
4477 constructor_constant = 1;
4478 constructor_simple = 1;
4479 constructor_depth = SPELLING_DEPTH ();
4480 constructor_elements = 0;
4481 constructor_pending_elts = 0;
4482 constructor_type = type;
4483 constructor_incremental = 1;
4484 constructor_designated = 0;
4485 designator_depth = 0;
4486 designator_errorneous = 0;
4488 if (TREE_CODE (constructor_type) == RECORD_TYPE
4489 || TREE_CODE (constructor_type) == UNION_TYPE)
4491 constructor_fields = TYPE_FIELDS (constructor_type);
4492 /* Skip any nameless bit fields at the beginning. */
4493 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4494 && DECL_NAME (constructor_fields) == 0)
4495 constructor_fields = TREE_CHAIN (constructor_fields);
4497 constructor_unfilled_fields = constructor_fields;
4498 constructor_bit_index = bitsize_zero_node;
4500 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4502 if (TYPE_DOMAIN (constructor_type))
4504 constructor_max_index
4505 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4507 /* Detect non-empty initializations of zero-length arrays. */
4508 if (constructor_max_index == NULL_TREE
4509 && TYPE_SIZE (constructor_type))
4510 constructor_max_index = build_int_2 (-1, -1);
4512 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4513 to initialize VLAs will cause a proper error; avoid tree
4514 checking errors as well by setting a safe value. */
4515 if (constructor_max_index
4516 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4517 constructor_max_index = build_int_2 (-1, -1);
4520 = convert (bitsizetype,
4521 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4524 constructor_index = bitsize_zero_node;
4526 constructor_unfilled_index = constructor_index;
4528 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4530 /* Vectors are like simple fixed-size arrays. */
4531 constructor_max_index =
4532 build_int_2 (TYPE_VECTOR_SUBPARTS (constructor_type) - 1, 0);
4533 constructor_index = convert (bitsizetype, bitsize_zero_node);
4534 constructor_unfilled_index = constructor_index;
4538 /* Handle the case of int x = {5}; */
4539 constructor_fields = constructor_type;
4540 constructor_unfilled_fields = constructor_type;
4544 /* Push down into a subobject, for initialization.
4545 If this is for an explicit set of braces, IMPLICIT is 0.
4546 If it is because the next element belongs at a lower level,
4547 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4550 push_init_level (int implicit)
4552 struct constructor_stack *p;
4553 tree value = NULL_TREE;
4555 /* If we've exhausted any levels that didn't have braces,
4557 while (constructor_stack->implicit)
4559 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4560 || TREE_CODE (constructor_type) == UNION_TYPE)
4561 && constructor_fields == 0)
4562 process_init_element (pop_init_level (1));
4563 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4564 && constructor_max_index
4565 && tree_int_cst_lt (constructor_max_index, constructor_index))
4566 process_init_element (pop_init_level (1));
4571 /* Unless this is an explicit brace, we need to preserve previous
4575 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4576 || TREE_CODE (constructor_type) == UNION_TYPE)
4577 && constructor_fields)
4578 value = find_init_member (constructor_fields);
4579 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4580 value = find_init_member (constructor_index);
4583 p = xmalloc (sizeof (struct constructor_stack));
4584 p->type = constructor_type;
4585 p->fields = constructor_fields;
4586 p->index = constructor_index;
4587 p->max_index = constructor_max_index;
4588 p->unfilled_index = constructor_unfilled_index;
4589 p->unfilled_fields = constructor_unfilled_fields;
4590 p->bit_index = constructor_bit_index;
4591 p->elements = constructor_elements;
4592 p->constant = constructor_constant;
4593 p->simple = constructor_simple;
4594 p->erroneous = constructor_erroneous;
4595 p->pending_elts = constructor_pending_elts;
4596 p->depth = constructor_depth;
4597 p->replacement_value = 0;
4598 p->implicit = implicit;
4600 p->incremental = constructor_incremental;
4601 p->designated = constructor_designated;
4602 p->next = constructor_stack;
4604 constructor_stack = p;
4606 constructor_constant = 1;
4607 constructor_simple = 1;
4608 constructor_depth = SPELLING_DEPTH ();
4609 constructor_elements = 0;
4610 constructor_incremental = 1;
4611 constructor_designated = 0;
4612 constructor_pending_elts = 0;
4615 p->range_stack = constructor_range_stack;
4616 constructor_range_stack = 0;
4617 designator_depth = 0;
4618 designator_errorneous = 0;
4621 /* Don't die if an entire brace-pair level is superfluous
4622 in the containing level. */
4623 if (constructor_type == 0)
4625 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4626 || TREE_CODE (constructor_type) == UNION_TYPE)
4628 /* Don't die if there are extra init elts at the end. */
4629 if (constructor_fields == 0)
4630 constructor_type = 0;
4633 constructor_type = TREE_TYPE (constructor_fields);
4634 push_member_name (constructor_fields);
4635 constructor_depth++;
4638 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4640 constructor_type = TREE_TYPE (constructor_type);
4641 push_array_bounds (tree_low_cst (constructor_index, 0));
4642 constructor_depth++;
4645 if (constructor_type == 0)
4647 error_init ("extra brace group at end of initializer");
4648 constructor_fields = 0;
4649 constructor_unfilled_fields = 0;
4653 if (value && TREE_CODE (value) == CONSTRUCTOR)
4655 constructor_constant = TREE_CONSTANT (value);
4656 constructor_simple = TREE_STATIC (value);
4657 constructor_elements = CONSTRUCTOR_ELTS (value);
4658 if (constructor_elements
4659 && (TREE_CODE (constructor_type) == RECORD_TYPE
4660 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4661 set_nonincremental_init ();
4664 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4666 missing_braces_mentioned = 1;
4667 warning_init ("missing braces around initializer");
4670 if (TREE_CODE (constructor_type) == RECORD_TYPE
4671 || TREE_CODE (constructor_type) == UNION_TYPE)
4673 constructor_fields = TYPE_FIELDS (constructor_type);
4674 /* Skip any nameless bit fields at the beginning. */
4675 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4676 && DECL_NAME (constructor_fields) == 0)
4677 constructor_fields = TREE_CHAIN (constructor_fields);
4679 constructor_unfilled_fields = constructor_fields;
4680 constructor_bit_index = bitsize_zero_node;
4682 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4684 /* Vectors are like simple fixed-size arrays. */
4685 constructor_max_index =
4686 build_int_2 (TYPE_VECTOR_SUBPARTS (constructor_type) - 1, 0);
4687 constructor_index = convert (bitsizetype, integer_zero_node);
4688 constructor_unfilled_index = constructor_index;
4690 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4692 if (TYPE_DOMAIN (constructor_type))
4694 constructor_max_index
4695 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4697 /* Detect non-empty initializations of zero-length arrays. */
4698 if (constructor_max_index == NULL_TREE
4699 && TYPE_SIZE (constructor_type))
4700 constructor_max_index = build_int_2 (-1, -1);
4702 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4703 to initialize VLAs will cause a proper error; avoid tree
4704 checking errors as well by setting a safe value. */
4705 if (constructor_max_index
4706 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4707 constructor_max_index = build_int_2 (-1, -1);
4710 = convert (bitsizetype,
4711 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4714 constructor_index = bitsize_zero_node;
4716 constructor_unfilled_index = constructor_index;
4717 if (value && TREE_CODE (value) == STRING_CST)
4719 /* We need to split the char/wchar array into individual
4720 characters, so that we don't have to special case it
4722 set_nonincremental_init_from_string (value);
4727 warning_init ("braces around scalar initializer");
4728 constructor_fields = constructor_type;
4729 constructor_unfilled_fields = constructor_type;
4733 /* At the end of an implicit or explicit brace level,
4734 finish up that level of constructor.
4735 If we were outputting the elements as they are read, return 0
4736 from inner levels (process_init_element ignores that),
4737 but return error_mark_node from the outermost level
4738 (that's what we want to put in DECL_INITIAL).
4739 Otherwise, return a CONSTRUCTOR expression. */
4742 pop_init_level (int implicit)
4744 struct constructor_stack *p;
4745 tree constructor = 0;
4749 /* When we come to an explicit close brace,
4750 pop any inner levels that didn't have explicit braces. */
4751 while (constructor_stack->implicit)
4752 process_init_element (pop_init_level (1));
4754 if (constructor_range_stack)
4758 /* Now output all pending elements. */
4759 constructor_incremental = 1;
4760 output_pending_init_elements (1);
4762 p = constructor_stack;
4764 /* Error for initializing a flexible array member, or a zero-length
4765 array member in an inappropriate context. */
4766 if (constructor_type && constructor_fields
4767 && TREE_CODE (constructor_type) == ARRAY_TYPE
4768 && TYPE_DOMAIN (constructor_type)
4769 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
4771 /* Silently discard empty initializations. The parser will
4772 already have pedwarned for empty brackets. */
4773 if (integer_zerop (constructor_unfilled_index))
4774 constructor_type = NULL_TREE;
4775 else if (! TYPE_SIZE (constructor_type))
4777 if (constructor_depth > 2)
4778 error_init ("initialization of flexible array member in a nested context");
4780 pedwarn_init ("initialization of a flexible array member");
4782 /* We have already issued an error message for the existence
4783 of a flexible array member not at the end of the structure.
4784 Discard the initializer so that we do not abort later. */
4785 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
4786 constructor_type = NULL_TREE;
4789 /* Zero-length arrays are no longer special, so we should no longer
4794 /* Warn when some struct elements are implicitly initialized to zero. */
4797 && TREE_CODE (constructor_type) == RECORD_TYPE
4798 && constructor_unfilled_fields)
4800 /* Do not warn for flexible array members or zero-length arrays. */
4801 while (constructor_unfilled_fields
4802 && (! DECL_SIZE (constructor_unfilled_fields)
4803 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
4804 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
4806 /* Do not warn if this level of the initializer uses member
4807 designators; it is likely to be deliberate. */
4808 if (constructor_unfilled_fields && !constructor_designated)
4810 push_member_name (constructor_unfilled_fields);
4811 warning_init ("missing initializer");
4812 RESTORE_SPELLING_DEPTH (constructor_depth);
4816 /* Pad out the end of the structure. */
4817 if (p->replacement_value)
4818 /* If this closes a superfluous brace pair,
4819 just pass out the element between them. */
4820 constructor = p->replacement_value;
4821 else if (constructor_type == 0)
4823 else if (TREE_CODE (constructor_type) != RECORD_TYPE
4824 && TREE_CODE (constructor_type) != UNION_TYPE
4825 && TREE_CODE (constructor_type) != ARRAY_TYPE
4826 && TREE_CODE (constructor_type) != VECTOR_TYPE)
4828 /* A nonincremental scalar initializer--just return
4829 the element, after verifying there is just one. */
4830 if (constructor_elements == 0)
4832 if (!constructor_erroneous)
4833 error_init ("empty scalar initializer");
4834 constructor = error_mark_node;
4836 else if (TREE_CHAIN (constructor_elements) != 0)
4838 error_init ("extra elements in scalar initializer");
4839 constructor = TREE_VALUE (constructor_elements);
4842 constructor = TREE_VALUE (constructor_elements);
4846 if (constructor_erroneous)
4847 constructor = error_mark_node;
4850 constructor = build_constructor (constructor_type,
4851 nreverse (constructor_elements));
4852 if (constructor_constant)
4853 TREE_CONSTANT (constructor) = TREE_INVARIANT (constructor) = 1;
4854 if (constructor_constant && constructor_simple)
4855 TREE_STATIC (constructor) = 1;
4859 constructor_type = p->type;
4860 constructor_fields = p->fields;
4861 constructor_index = p->index;
4862 constructor_max_index = p->max_index;
4863 constructor_unfilled_index = p->unfilled_index;
4864 constructor_unfilled_fields = p->unfilled_fields;
4865 constructor_bit_index = p->bit_index;
4866 constructor_elements = p->elements;
4867 constructor_constant = p->constant;
4868 constructor_simple = p->simple;
4869 constructor_erroneous = p->erroneous;
4870 constructor_incremental = p->incremental;
4871 constructor_designated = p->designated;
4872 constructor_pending_elts = p->pending_elts;
4873 constructor_depth = p->depth;
4875 constructor_range_stack = p->range_stack;
4876 RESTORE_SPELLING_DEPTH (constructor_depth);
4878 constructor_stack = p->next;
4881 if (constructor == 0)
4883 if (constructor_stack == 0)
4884 return error_mark_node;
4890 /* Common handling for both array range and field name designators.
4891 ARRAY argument is nonzero for array ranges. Returns zero for success. */
4894 set_designator (int array)
4897 enum tree_code subcode;
4899 /* Don't die if an entire brace-pair level is superfluous
4900 in the containing level. */
4901 if (constructor_type == 0)
4904 /* If there were errors in this designator list already, bail out silently. */
4905 if (designator_errorneous)
4908 if (!designator_depth)
4910 if (constructor_range_stack)
4913 /* Designator list starts at the level of closest explicit
4915 while (constructor_stack->implicit)
4916 process_init_element (pop_init_level (1));
4917 constructor_designated = 1;
4921 if (constructor_no_implicit)
4923 error_init ("initialization designators may not nest");
4927 if (TREE_CODE (constructor_type) == RECORD_TYPE
4928 || TREE_CODE (constructor_type) == UNION_TYPE)
4930 subtype = TREE_TYPE (constructor_fields);
4931 if (subtype != error_mark_node)
4932 subtype = TYPE_MAIN_VARIANT (subtype);
4934 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4936 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
4941 subcode = TREE_CODE (subtype);
4942 if (array && subcode != ARRAY_TYPE)
4944 error_init ("array index in non-array initializer");
4947 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
4949 error_init ("field name not in record or union initializer");
4953 constructor_designated = 1;
4954 push_init_level (2);
4958 /* If there are range designators in designator list, push a new designator
4959 to constructor_range_stack. RANGE_END is end of such stack range or
4960 NULL_TREE if there is no range designator at this level. */
4963 push_range_stack (tree range_end)
4965 struct constructor_range_stack *p;
4967 p = ggc_alloc (sizeof (struct constructor_range_stack));
4968 p->prev = constructor_range_stack;
4970 p->fields = constructor_fields;
4971 p->range_start = constructor_index;
4972 p->index = constructor_index;
4973 p->stack = constructor_stack;
4974 p->range_end = range_end;
4975 if (constructor_range_stack)
4976 constructor_range_stack->next = p;
4977 constructor_range_stack = p;
4980 /* Within an array initializer, specify the next index to be initialized.
4981 FIRST is that index. If LAST is nonzero, then initialize a range
4982 of indices, running from FIRST through LAST. */
4985 set_init_index (tree first, tree last)
4987 if (set_designator (1))
4990 designator_errorneous = 1;
4992 while ((TREE_CODE (first) == NOP_EXPR
4993 || TREE_CODE (first) == CONVERT_EXPR
4994 || TREE_CODE (first) == NON_LVALUE_EXPR)
4995 && (TYPE_MODE (TREE_TYPE (first))
4996 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (first, 0)))))
4997 first = TREE_OPERAND (first, 0);
5000 while ((TREE_CODE (last) == NOP_EXPR
5001 || TREE_CODE (last) == CONVERT_EXPR
5002 || TREE_CODE (last) == NON_LVALUE_EXPR)
5003 && (TYPE_MODE (TREE_TYPE (last))
5004 == TYPE_MODE (TREE_TYPE (TREE_OPERAND (last, 0)))))
5005 last = TREE_OPERAND (last, 0);
5007 if (TREE_CODE (first) != INTEGER_CST)
5008 error_init ("nonconstant array index in initializer");
5009 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5010 error_init ("nonconstant array index in initializer");
5011 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5012 error_init ("array index in non-array initializer");
5013 else if (tree_int_cst_sgn (first) == -1)
5014 error_init ("array index in initializer exceeds array bounds");
5015 else if (constructor_max_index
5016 && tree_int_cst_lt (constructor_max_index, first))
5017 error_init ("array index in initializer exceeds array bounds");
5020 constructor_index = convert (bitsizetype, first);
5024 if (tree_int_cst_equal (first, last))
5026 else if (tree_int_cst_lt (last, first))
5028 error_init ("empty index range in initializer");
5033 last = convert (bitsizetype, last);
5034 if (constructor_max_index != 0
5035 && tree_int_cst_lt (constructor_max_index, last))
5037 error_init ("array index range in initializer exceeds array bounds");
5044 designator_errorneous = 0;
5045 if (constructor_range_stack || last)
5046 push_range_stack (last);
5050 /* Within a struct initializer, specify the next field to be initialized. */
5053 set_init_label (tree fieldname)
5057 if (set_designator (0))
5060 designator_errorneous = 1;
5062 if (TREE_CODE (constructor_type) != RECORD_TYPE
5063 && TREE_CODE (constructor_type) != UNION_TYPE)
5065 error_init ("field name not in record or union initializer");
5069 for (tail = TYPE_FIELDS (constructor_type); tail;
5070 tail = TREE_CHAIN (tail))
5072 if (DECL_NAME (tail) == fieldname)
5077 error ("unknown field `%s' specified in initializer",
5078 IDENTIFIER_POINTER (fieldname));
5081 constructor_fields = tail;
5083 designator_errorneous = 0;
5084 if (constructor_range_stack)
5085 push_range_stack (NULL_TREE);
5089 /* Add a new initializer to the tree of pending initializers. PURPOSE
5090 identifies the initializer, either array index or field in a structure.
5091 VALUE is the value of that index or field. */
5094 add_pending_init (tree purpose, tree value)
5096 struct init_node *p, **q, *r;
5098 q = &constructor_pending_elts;
5101 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5106 if (tree_int_cst_lt (purpose, p->purpose))
5108 else if (tree_int_cst_lt (p->purpose, purpose))
5112 if (TREE_SIDE_EFFECTS (p->value))
5113 warning_init ("initialized field with side-effects overwritten");
5123 bitpos = bit_position (purpose);
5127 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5129 else if (p->purpose != purpose)
5133 if (TREE_SIDE_EFFECTS (p->value))
5134 warning_init ("initialized field with side-effects overwritten");
5141 r = ggc_alloc (sizeof (struct init_node));
5142 r->purpose = purpose;
5153 struct init_node *s;
5157 if (p->balance == 0)
5159 else if (p->balance < 0)
5166 p->left->parent = p;
5183 constructor_pending_elts = r;
5188 struct init_node *t = r->right;
5192 r->right->parent = r;
5197 p->left->parent = p;
5200 p->balance = t->balance < 0;
5201 r->balance = -(t->balance > 0);
5216 constructor_pending_elts = t;
5222 /* p->balance == +1; growth of left side balances the node. */
5227 else /* r == p->right */
5229 if (p->balance == 0)
5230 /* Growth propagation from right side. */
5232 else if (p->balance > 0)
5239 p->right->parent = p;
5256 constructor_pending_elts = r;
5258 else /* r->balance == -1 */
5261 struct init_node *t = r->left;
5265 r->left->parent = r;
5270 p->right->parent = p;
5273 r->balance = (t->balance < 0);
5274 p->balance = -(t->balance > 0);
5289 constructor_pending_elts = t;
5295 /* p->balance == -1; growth of right side balances the node. */
5306 /* Build AVL tree from a sorted chain. */
5309 set_nonincremental_init (void)
5313 if (TREE_CODE (constructor_type) != RECORD_TYPE
5314 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5317 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5318 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5319 constructor_elements = 0;
5320 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5322 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5323 /* Skip any nameless bit fields at the beginning. */
5324 while (constructor_unfilled_fields != 0
5325 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5326 && DECL_NAME (constructor_unfilled_fields) == 0)
5327 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5330 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5332 if (TYPE_DOMAIN (constructor_type))
5333 constructor_unfilled_index
5334 = convert (bitsizetype,
5335 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5337 constructor_unfilled_index = bitsize_zero_node;
5339 constructor_incremental = 0;
5342 /* Build AVL tree from a string constant. */
5345 set_nonincremental_init_from_string (tree str)
5347 tree value, purpose, type;
5348 HOST_WIDE_INT val[2];
5349 const char *p, *end;
5350 int byte, wchar_bytes, charwidth, bitpos;
5352 if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5355 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5356 == TYPE_PRECISION (char_type_node))
5358 else if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5359 == TYPE_PRECISION (wchar_type_node))
5360 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5364 charwidth = TYPE_PRECISION (char_type_node);
5365 type = TREE_TYPE (constructor_type);
5366 p = TREE_STRING_POINTER (str);
5367 end = p + TREE_STRING_LENGTH (str);
5369 for (purpose = bitsize_zero_node;
5370 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5371 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5373 if (wchar_bytes == 1)
5375 val[1] = (unsigned char) *p++;
5382 for (byte = 0; byte < wchar_bytes; byte++)
5384 if (BYTES_BIG_ENDIAN)
5385 bitpos = (wchar_bytes - byte - 1) * charwidth;
5387 bitpos = byte * charwidth;
5388 val[bitpos < HOST_BITS_PER_WIDE_INT]
5389 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5390 << (bitpos % HOST_BITS_PER_WIDE_INT);
5394 if (!TYPE_UNSIGNED (type))
5396 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5397 if (bitpos < HOST_BITS_PER_WIDE_INT)
5399 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5401 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5405 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5410 else if (val[0] & (((HOST_WIDE_INT) 1)
5411 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5412 val[0] |= ((HOST_WIDE_INT) -1)
5413 << (bitpos - HOST_BITS_PER_WIDE_INT);
5416 value = build_int_2 (val[1], val[0]);
5417 TREE_TYPE (value) = type;
5418 add_pending_init (purpose, value);
5421 constructor_incremental = 0;
5424 /* Return value of FIELD in pending initializer or zero if the field was
5425 not initialized yet. */
5428 find_init_member (tree field)
5430 struct init_node *p;
5432 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5434 if (constructor_incremental
5435 && tree_int_cst_lt (field, constructor_unfilled_index))
5436 set_nonincremental_init ();
5438 p = constructor_pending_elts;
5441 if (tree_int_cst_lt (field, p->purpose))
5443 else if (tree_int_cst_lt (p->purpose, field))
5449 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5451 tree bitpos = bit_position (field);
5453 if (constructor_incremental
5454 && (!constructor_unfilled_fields
5455 || tree_int_cst_lt (bitpos,
5456 bit_position (constructor_unfilled_fields))))
5457 set_nonincremental_init ();
5459 p = constructor_pending_elts;
5462 if (field == p->purpose)
5464 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5470 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5472 if (constructor_elements
5473 && TREE_PURPOSE (constructor_elements) == field)
5474 return TREE_VALUE (constructor_elements);
5479 /* "Output" the next constructor element.
5480 At top level, really output it to assembler code now.
5481 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5482 TYPE is the data type that the containing data type wants here.
5483 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5485 PENDING if non-nil means output pending elements that belong
5486 right after this element. (PENDING is normally 1;
5487 it is 0 while outputting pending elements, to avoid recursion.) */
5490 output_init_element (tree value, tree type, tree field, int pending)
5492 if (type == error_mark_node)
5494 constructor_erroneous = 1;
5497 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5498 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5499 && !(TREE_CODE (value) == STRING_CST
5500 && TREE_CODE (type) == ARRAY_TYPE
5501 && TREE_CODE (TREE_TYPE (type)) == INTEGER_TYPE)
5502 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5503 TYPE_MAIN_VARIANT (type), COMPARE_STRICT)))
5504 value = default_conversion (value);
5506 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5507 && require_constant_value && !flag_isoc99 && pending)
5509 /* As an extension, allow initializing objects with static storage
5510 duration with compound literals (which are then treated just as
5511 the brace enclosed list they contain). */
5512 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5513 value = DECL_INITIAL (decl);
5516 if (value == error_mark_node)
5517 constructor_erroneous = 1;
5518 else if (!TREE_CONSTANT (value))
5519 constructor_constant = 0;
5520 else if (initializer_constant_valid_p (value, TREE_TYPE (value)) == 0
5521 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5522 || TREE_CODE (constructor_type) == UNION_TYPE)
5523 && DECL_C_BIT_FIELD (field)
5524 && TREE_CODE (value) != INTEGER_CST))
5525 constructor_simple = 0;
5527 if (require_constant_value && ! TREE_CONSTANT (value))
5529 error_init ("initializer element is not constant");
5530 value = error_mark_node;
5532 else if (require_constant_elements
5533 && initializer_constant_valid_p (value, TREE_TYPE (value)) == 0)
5534 pedwarn ("initializer element is not computable at load time");
5536 /* If this field is empty (and not at the end of structure),
5537 don't do anything other than checking the initializer. */
5539 && (TREE_TYPE (field) == error_mark_node
5540 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5541 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5542 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5543 || TREE_CHAIN (field)))))
5546 value = digest_init (type, value, require_constant_value);
5547 if (value == error_mark_node)
5549 constructor_erroneous = 1;
5553 /* If this element doesn't come next in sequence,
5554 put it on constructor_pending_elts. */
5555 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5556 && (!constructor_incremental
5557 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5559 if (constructor_incremental
5560 && tree_int_cst_lt (field, constructor_unfilled_index))
5561 set_nonincremental_init ();
5563 add_pending_init (field, value);
5566 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5567 && (!constructor_incremental
5568 || field != constructor_unfilled_fields))
5570 /* We do this for records but not for unions. In a union,
5571 no matter which field is specified, it can be initialized
5572 right away since it starts at the beginning of the union. */
5573 if (constructor_incremental)
5575 if (!constructor_unfilled_fields)
5576 set_nonincremental_init ();
5579 tree bitpos, unfillpos;
5581 bitpos = bit_position (field);
5582 unfillpos = bit_position (constructor_unfilled_fields);
5584 if (tree_int_cst_lt (bitpos, unfillpos))
5585 set_nonincremental_init ();
5589 add_pending_init (field, value);
5592 else if (TREE_CODE (constructor_type) == UNION_TYPE
5593 && constructor_elements)
5595 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5596 warning_init ("initialized field with side-effects overwritten");
5598 /* We can have just one union field set. */
5599 constructor_elements = 0;
5602 /* Otherwise, output this element either to
5603 constructor_elements or to the assembler file. */
5605 if (field && TREE_CODE (field) == INTEGER_CST)
5606 field = copy_node (field);
5607 constructor_elements
5608 = tree_cons (field, value, constructor_elements);
5610 /* Advance the variable that indicates sequential elements output. */
5611 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5612 constructor_unfilled_index
5613 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5615 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5617 constructor_unfilled_fields
5618 = TREE_CHAIN (constructor_unfilled_fields);
5620 /* Skip any nameless bit fields. */
5621 while (constructor_unfilled_fields != 0
5622 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5623 && DECL_NAME (constructor_unfilled_fields) == 0)
5624 constructor_unfilled_fields =
5625 TREE_CHAIN (constructor_unfilled_fields);
5627 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5628 constructor_unfilled_fields = 0;
5630 /* Now output any pending elements which have become next. */
5632 output_pending_init_elements (0);
5635 /* Output any pending elements which have become next.
5636 As we output elements, constructor_unfilled_{fields,index}
5637 advances, which may cause other elements to become next;
5638 if so, they too are output.
5640 If ALL is 0, we return when there are
5641 no more pending elements to output now.
5643 If ALL is 1, we output space as necessary so that
5644 we can output all the pending elements. */
5647 output_pending_init_elements (int all)
5649 struct init_node *elt = constructor_pending_elts;
5654 /* Look through the whole pending tree.
5655 If we find an element that should be output now,
5656 output it. Otherwise, set NEXT to the element
5657 that comes first among those still pending. */
5662 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5664 if (tree_int_cst_equal (elt->purpose,
5665 constructor_unfilled_index))
5666 output_init_element (elt->value,
5667 TREE_TYPE (constructor_type),
5668 constructor_unfilled_index, 0);
5669 else if (tree_int_cst_lt (constructor_unfilled_index,
5672 /* Advance to the next smaller node. */
5677 /* We have reached the smallest node bigger than the
5678 current unfilled index. Fill the space first. */
5679 next = elt->purpose;
5685 /* Advance to the next bigger node. */
5690 /* We have reached the biggest node in a subtree. Find
5691 the parent of it, which is the next bigger node. */
5692 while (elt->parent && elt->parent->right == elt)
5695 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5698 next = elt->purpose;
5704 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5705 || TREE_CODE (constructor_type) == UNION_TYPE)
5707 tree ctor_unfilled_bitpos, elt_bitpos;
5709 /* If the current record is complete we are done. */
5710 if (constructor_unfilled_fields == 0)
5713 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
5714 elt_bitpos = bit_position (elt->purpose);
5715 /* We can't compare fields here because there might be empty
5716 fields in between. */
5717 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
5719 constructor_unfilled_fields = elt->purpose;
5720 output_init_element (elt->value, TREE_TYPE (elt->purpose),
5723 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
5725 /* Advance to the next smaller node. */
5730 /* We have reached the smallest node bigger than the
5731 current unfilled field. Fill the space first. */
5732 next = elt->purpose;
5738 /* Advance to the next bigger node. */
5743 /* We have reached the biggest node in a subtree. Find
5744 the parent of it, which is the next bigger node. */
5745 while (elt->parent && elt->parent->right == elt)
5749 && (tree_int_cst_lt (ctor_unfilled_bitpos,
5750 bit_position (elt->purpose))))
5752 next = elt->purpose;
5760 /* Ordinarily return, but not if we want to output all
5761 and there are elements left. */
5762 if (! (all && next != 0))
5765 /* If it's not incremental, just skip over the gap, so that after
5766 jumping to retry we will output the next successive element. */
5767 if (TREE_CODE (constructor_type) == RECORD_TYPE
5768 || TREE_CODE (constructor_type) == UNION_TYPE)
5769 constructor_unfilled_fields = next;
5770 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5771 constructor_unfilled_index = next;
5773 /* ELT now points to the node in the pending tree with the next
5774 initializer to output. */
5778 /* Add one non-braced element to the current constructor level.
5779 This adjusts the current position within the constructor's type.
5780 This may also start or terminate implicit levels
5781 to handle a partly-braced initializer.
5783 Once this has found the correct level for the new element,
5784 it calls output_init_element. */
5787 process_init_element (tree value)
5789 tree orig_value = value;
5790 int string_flag = value != 0 && TREE_CODE (value) == STRING_CST;
5792 designator_depth = 0;
5793 designator_errorneous = 0;
5795 /* Handle superfluous braces around string cst as in
5796 char x[] = {"foo"}; */
5799 && TREE_CODE (constructor_type) == ARRAY_TYPE
5800 && TREE_CODE (TREE_TYPE (constructor_type)) == INTEGER_TYPE
5801 && integer_zerop (constructor_unfilled_index))
5803 if (constructor_stack->replacement_value)
5804 error_init ("excess elements in char array initializer");
5805 constructor_stack->replacement_value = value;
5809 if (constructor_stack->replacement_value != 0)
5811 error_init ("excess elements in struct initializer");
5815 /* Ignore elements of a brace group if it is entirely superfluous
5816 and has already been diagnosed. */
5817 if (constructor_type == 0)
5820 /* If we've exhausted any levels that didn't have braces,
5822 while (constructor_stack->implicit)
5824 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5825 || TREE_CODE (constructor_type) == UNION_TYPE)
5826 && constructor_fields == 0)
5827 process_init_element (pop_init_level (1));
5828 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5829 && (constructor_max_index == 0
5830 || tree_int_cst_lt (constructor_max_index,
5831 constructor_index)))
5832 process_init_element (pop_init_level (1));
5837 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
5838 if (constructor_range_stack)
5840 /* If value is a compound literal and we'll be just using its
5841 content, don't put it into a SAVE_EXPR. */
5842 if (TREE_CODE (value) != COMPOUND_LITERAL_EXPR
5843 || !require_constant_value
5845 value = save_expr (value);
5850 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5853 enum tree_code fieldcode;
5855 if (constructor_fields == 0)
5857 pedwarn_init ("excess elements in struct initializer");
5861 fieldtype = TREE_TYPE (constructor_fields);
5862 if (fieldtype != error_mark_node)
5863 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
5864 fieldcode = TREE_CODE (fieldtype);
5866 /* Error for non-static initialization of a flexible array member. */
5867 if (fieldcode == ARRAY_TYPE
5868 && !require_constant_value
5869 && TYPE_SIZE (fieldtype) == NULL_TREE
5870 && TREE_CHAIN (constructor_fields) == NULL_TREE)
5872 error_init ("non-static initialization of a flexible array member");
5876 /* Accept a string constant to initialize a subarray. */
5878 && fieldcode == ARRAY_TYPE
5879 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
5882 /* Otherwise, if we have come to a subaggregate,
5883 and we don't have an element of its type, push into it. */
5884 else if (value != 0 && !constructor_no_implicit
5885 && value != error_mark_node
5886 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
5887 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
5888 || fieldcode == UNION_TYPE))
5890 push_init_level (1);
5896 push_member_name (constructor_fields);
5897 output_init_element (value, fieldtype, constructor_fields, 1);
5898 RESTORE_SPELLING_DEPTH (constructor_depth);
5901 /* Do the bookkeeping for an element that was
5902 directly output as a constructor. */
5904 /* For a record, keep track of end position of last field. */
5905 if (DECL_SIZE (constructor_fields))
5906 constructor_bit_index
5907 = size_binop (PLUS_EXPR,
5908 bit_position (constructor_fields),
5909 DECL_SIZE (constructor_fields));
5911 /* If the current field was the first one not yet written out,
5912 it isn't now, so update. */
5913 if (constructor_unfilled_fields == constructor_fields)
5915 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
5916 /* Skip any nameless bit fields. */
5917 while (constructor_unfilled_fields != 0
5918 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5919 && DECL_NAME (constructor_unfilled_fields) == 0)
5920 constructor_unfilled_fields =
5921 TREE_CHAIN (constructor_unfilled_fields);
5925 constructor_fields = TREE_CHAIN (constructor_fields);
5926 /* Skip any nameless bit fields at the beginning. */
5927 while (constructor_fields != 0
5928 && DECL_C_BIT_FIELD (constructor_fields)
5929 && DECL_NAME (constructor_fields) == 0)
5930 constructor_fields = TREE_CHAIN (constructor_fields);
5932 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5935 enum tree_code fieldcode;
5937 if (constructor_fields == 0)
5939 pedwarn_init ("excess elements in union initializer");
5943 fieldtype = TREE_TYPE (constructor_fields);
5944 if (fieldtype != error_mark_node)
5945 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
5946 fieldcode = TREE_CODE (fieldtype);
5948 /* Warn that traditional C rejects initialization of unions.
5949 We skip the warning if the value is zero. This is done
5950 under the assumption that the zero initializer in user
5951 code appears conditioned on e.g. __STDC__ to avoid
5952 "missing initializer" warnings and relies on default
5953 initialization to zero in the traditional C case.
5954 We also skip the warning if the initializer is designated,
5955 again on the assumption that this must be conditional on
5956 __STDC__ anyway (and we've already complained about the
5957 member-designator already). */
5958 if (warn_traditional && !in_system_header && !constructor_designated
5959 && !(value && (integer_zerop (value) || real_zerop (value))))
5960 warning ("traditional C rejects initialization of unions");
5962 /* Accept a string constant to initialize a subarray. */
5964 && fieldcode == ARRAY_TYPE
5965 && TREE_CODE (TREE_TYPE (fieldtype)) == INTEGER_TYPE
5968 /* Otherwise, if we have come to a subaggregate,
5969 and we don't have an element of its type, push into it. */
5970 else if (value != 0 && !constructor_no_implicit
5971 && value != error_mark_node
5972 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != fieldtype
5973 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
5974 || fieldcode == UNION_TYPE))
5976 push_init_level (1);
5982 push_member_name (constructor_fields);
5983 output_init_element (value, fieldtype, constructor_fields, 1);
5984 RESTORE_SPELLING_DEPTH (constructor_depth);
5987 /* Do the bookkeeping for an element that was
5988 directly output as a constructor. */
5990 constructor_bit_index = DECL_SIZE (constructor_fields);
5991 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
5994 constructor_fields = 0;
5996 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5998 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5999 enum tree_code eltcode = TREE_CODE (elttype);
6001 /* Accept a string constant to initialize a subarray. */
6003 && eltcode == ARRAY_TYPE
6004 && TREE_CODE (TREE_TYPE (elttype)) == INTEGER_TYPE
6007 /* Otherwise, if we have come to a subaggregate,
6008 and we don't have an element of its type, push into it. */
6009 else if (value != 0 && !constructor_no_implicit
6010 && value != error_mark_node
6011 && TYPE_MAIN_VARIANT (TREE_TYPE (value)) != elttype
6012 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6013 || eltcode == UNION_TYPE))
6015 push_init_level (1);
6019 if (constructor_max_index != 0
6020 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6021 || integer_all_onesp (constructor_max_index)))
6023 pedwarn_init ("excess elements in array initializer");
6027 /* Now output the actual element. */
6030 push_array_bounds (tree_low_cst (constructor_index, 0));
6031 output_init_element (value, elttype, constructor_index, 1);
6032 RESTORE_SPELLING_DEPTH (constructor_depth);
6036 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6039 /* If we are doing the bookkeeping for an element that was
6040 directly output as a constructor, we must update
6041 constructor_unfilled_index. */
6042 constructor_unfilled_index = constructor_index;
6044 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6046 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6048 /* Do a basic check of initializer size. Note that vectors
6049 always have a fixed size derived from their type. */
6050 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6052 pedwarn_init ("excess elements in vector initializer");
6056 /* Now output the actual element. */
6058 output_init_element (value, elttype, constructor_index, 1);
6061 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6064 /* If we are doing the bookkeeping for an element that was
6065 directly output as a constructor, we must update
6066 constructor_unfilled_index. */
6067 constructor_unfilled_index = constructor_index;
6070 /* Handle the sole element allowed in a braced initializer
6071 for a scalar variable. */
6072 else if (constructor_fields == 0)
6074 pedwarn_init ("excess elements in scalar initializer");
6080 output_init_element (value, constructor_type, NULL_TREE, 1);
6081 constructor_fields = 0;
6084 /* Handle range initializers either at this level or anywhere higher
6085 in the designator stack. */
6086 if (constructor_range_stack)
6088 struct constructor_range_stack *p, *range_stack;
6091 range_stack = constructor_range_stack;
6092 constructor_range_stack = 0;
6093 while (constructor_stack != range_stack->stack)
6095 if (!constructor_stack->implicit)
6097 process_init_element (pop_init_level (1));
6099 for (p = range_stack;
6100 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6103 if (!constructor_stack->implicit)
6105 process_init_element (pop_init_level (1));
6108 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6109 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6114 constructor_index = p->index;
6115 constructor_fields = p->fields;
6116 if (finish && p->range_end && p->index == p->range_start)
6124 push_init_level (2);
6125 p->stack = constructor_stack;
6126 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6127 p->index = p->range_start;
6131 constructor_range_stack = range_stack;
6138 constructor_range_stack = 0;
6141 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6142 (guaranteed to be 'volatile' or null) and ARGS (represented using
6143 an ASM_STMT node). */
6145 build_asm_stmt (tree cv_qualifier, tree args)
6147 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6148 ASM_VOLATILE_P (args) = 1;
6149 return add_stmt (args);
6152 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6153 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6154 SIMPLE indicates whether there was anything at all after the
6155 string in the asm expression -- asm("blah") and asm("blah" : )
6156 are subtly different. We use a ASM_STMT node to represent this. */
6158 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6164 const char *constraint;
6165 bool allows_mem, allows_reg, is_inout;
6169 ninputs = list_length (inputs);
6170 noutputs = list_length (outputs);
6172 /* Remove output conversions that change the type but not the mode. */
6173 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6175 tree output = TREE_VALUE (tail);
6176 STRIP_NOPS (output);
6177 TREE_VALUE (tail) = output;
6178 lvalue_or_else (output, "invalid lvalue in asm statement");
6180 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6182 if (!parse_output_constraint (&constraint, i, ninputs, noutputs,
6183 &allows_mem, &allows_reg, &is_inout))
6185 /* By marking this operand as erroneous, we will not try
6186 to process this operand again in expand_asm_operands. */
6187 TREE_VALUE (tail) = error_mark_node;
6191 /* If the operand is a DECL that is going to end up in
6192 memory, assume it is addressable. This is a bit more
6193 conservative than it would ideally be; the exact test is
6194 buried deep in expand_asm_operands and depends on the
6195 DECL_RTL for the OPERAND -- which we don't have at this
6197 if (!allows_reg && DECL_P (output))
6198 c_mark_addressable (output);
6201 /* Perform default conversions on array and function inputs.
6202 Don't do this for other types as it would screw up operands
6203 expected to be in memory. */
6204 for (tail = inputs; tail; tail = TREE_CHAIN (tail))
6205 TREE_VALUE (tail) = default_function_array_conversion (TREE_VALUE (tail));
6207 args = build_stmt (ASM_STMT, string, outputs, inputs, clobbers);
6209 /* Simple asm statements are treated as volatile. */
6212 ASM_VOLATILE_P (args) = 1;
6213 ASM_INPUT_P (args) = 1;
6218 /* Expand an ASM statement with operands, handling output operands
6219 that are not variables or INDIRECT_REFS by transforming such
6220 cases into cases that expand_asm_operands can handle.
6222 Arguments are same as for expand_asm_operands. */
6225 c_expand_asm_operands (tree string, tree outputs, tree inputs,
6226 tree clobbers, int vol, location_t locus)
6228 int noutputs = list_length (outputs);
6230 /* o[I] is the place that output number I should be written. */
6231 tree *o = alloca (noutputs * sizeof (tree));
6234 /* Record the contents of OUTPUTS before it is modified. */
6235 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6237 o[i] = TREE_VALUE (tail);
6238 if (o[i] == error_mark_node)
6242 /* Generate the ASM_OPERANDS insn; store into the TREE_VALUEs of
6243 OUTPUTS some trees for where the values were actually stored. */
6244 expand_asm_operands (string, outputs, inputs, clobbers, vol, locus);
6246 /* Copy all the intermediate outputs into the specified outputs. */
6247 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
6249 if (o[i] != TREE_VALUE (tail))
6251 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
6252 NULL_RTX, VOIDmode, EXPAND_NORMAL);
6255 /* Restore the original value so that it's correct the next
6256 time we expand this function. */
6257 TREE_VALUE (tail) = o[i];
6259 /* Detect modification of read-only values.
6260 (Otherwise done by build_modify_expr.) */
6263 tree type = TREE_TYPE (o[i]);
6264 if (TREE_READONLY (o[i])
6265 || TYPE_READONLY (type)
6266 || ((TREE_CODE (type) == RECORD_TYPE
6267 || TREE_CODE (type) == UNION_TYPE)
6268 && C_TYPE_FIELDS_READONLY (type)))
6269 readonly_error (o[i], "modification by `asm'");
6273 /* Those MODIFY_EXPRs could do autoincrements. */
6277 /* Expand a C `return' statement.
6278 RETVAL is the expression for what to return,
6279 or a null pointer for `return;' with no value. */
6282 c_expand_return (tree retval)
6284 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6286 if (TREE_THIS_VOLATILE (current_function_decl))
6287 warning ("function declared `noreturn' has a `return' statement");
6291 current_function_returns_null = 1;
6292 if ((warn_return_type || flag_isoc99)
6293 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6294 pedwarn_c99 ("`return' with no value, in function returning non-void");
6296 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6298 current_function_returns_null = 1;
6299 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6300 pedwarn ("`return' with a value, in function returning void");
6304 tree t = convert_for_assignment (valtype, retval, _("return"),
6305 NULL_TREE, NULL_TREE, 0);
6306 tree res = DECL_RESULT (current_function_decl);
6309 current_function_returns_value = 1;
6310 if (t == error_mark_node)
6313 inner = t = convert (TREE_TYPE (res), t);
6315 /* Strip any conversions, additions, and subtractions, and see if
6316 we are returning the address of a local variable. Warn if so. */
6319 switch (TREE_CODE (inner))
6321 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6323 inner = TREE_OPERAND (inner, 0);
6327 /* If the second operand of the MINUS_EXPR has a pointer
6328 type (or is converted from it), this may be valid, so
6329 don't give a warning. */
6331 tree op1 = TREE_OPERAND (inner, 1);
6333 while (! POINTER_TYPE_P (TREE_TYPE (op1))
6334 && (TREE_CODE (op1) == NOP_EXPR
6335 || TREE_CODE (op1) == NON_LVALUE_EXPR
6336 || TREE_CODE (op1) == CONVERT_EXPR))
6337 op1 = TREE_OPERAND (op1, 0);
6339 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6342 inner = TREE_OPERAND (inner, 0);
6347 inner = TREE_OPERAND (inner, 0);
6349 while (TREE_CODE_CLASS (TREE_CODE (inner)) == 'r')
6350 inner = TREE_OPERAND (inner, 0);
6353 && ! DECL_EXTERNAL (inner)
6354 && ! TREE_STATIC (inner)
6355 && DECL_CONTEXT (inner) == current_function_decl)
6356 warning ("function returns address of local variable");
6366 retval = build (MODIFY_EXPR, TREE_TYPE (res), res, t);
6369 return add_stmt (build_return_stmt (retval));
6373 /* The SWITCH_STMT being built. */
6375 /* A splay-tree mapping the low element of a case range to the high
6376 element, or NULL_TREE if there is no high element. Used to
6377 determine whether or not a new case label duplicates an old case
6378 label. We need a tree, rather than simply a hash table, because
6379 of the GNU case range extension. */
6381 /* The next node on the stack. */
6382 struct c_switch *next;
6385 /* A stack of the currently active switch statements. The innermost
6386 switch statement is on the top of the stack. There is no need to
6387 mark the stack for garbage collection because it is only active
6388 during the processing of the body of a function, and we never
6389 collect at that point. */
6391 static struct c_switch *switch_stack;
6393 /* Start a C switch statement, testing expression EXP. Return the new
6397 c_start_case (tree exp)
6399 enum tree_code code;
6400 tree type, orig_type = error_mark_node;
6401 struct c_switch *cs;
6403 if (exp != error_mark_node)
6405 code = TREE_CODE (TREE_TYPE (exp));
6406 orig_type = TREE_TYPE (exp);
6408 if (! INTEGRAL_TYPE_P (orig_type)
6409 && code != ERROR_MARK)
6411 error ("switch quantity not an integer");
6412 exp = integer_zero_node;
6416 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6418 if (warn_traditional && !in_system_header
6419 && (type == long_integer_type_node
6420 || type == long_unsigned_type_node))
6421 warning ("`long' switch expression not converted to `int' in ISO C");
6423 exp = default_conversion (exp);
6424 type = TREE_TYPE (exp);
6428 /* Add this new SWITCH_STMT to the stack. */
6429 cs = xmalloc (sizeof (*cs));
6430 cs->switch_stmt = build_stmt (SWITCH_STMT, exp, NULL_TREE, orig_type);
6431 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6432 cs->next = switch_stack;
6435 return add_stmt (switch_stack->switch_stmt);
6438 /* Process a case label. */
6441 do_case (tree low_value, tree high_value)
6443 tree label = NULL_TREE;
6447 bool switch_was_empty_p = (SWITCH_BODY (switch_stack->switch_stmt) == NULL_TREE);
6449 label = c_add_case_label (switch_stack->cases,
6450 SWITCH_COND (switch_stack->switch_stmt),
6451 low_value, high_value);
6452 if (label == error_mark_node)
6454 else if (switch_was_empty_p)
6456 /* Attach the first case label to the SWITCH_BODY. */
6457 SWITCH_BODY (switch_stack->switch_stmt) = TREE_CHAIN (switch_stack->switch_stmt);
6458 TREE_CHAIN (switch_stack->switch_stmt) = NULL_TREE;
6462 error ("case label not within a switch statement");
6464 error ("`default' label not within a switch statement");
6469 /* Finish the switch statement. */
6472 c_finish_case (void)
6474 struct c_switch *cs = switch_stack;
6476 /* Emit warnings as needed. */
6477 c_do_switch_warnings (cs->cases, cs->switch_stmt);
6479 /* Rechain the next statements to the SWITCH_STMT. */
6480 last_tree = cs->switch_stmt;
6482 /* Pop the stack. */
6483 switch_stack = switch_stack->next;
6484 splay_tree_delete (cs->cases);
6488 /* Build a binary-operation expression without default conversions.
6489 CODE is the kind of expression to build.
6490 This function differs from `build' in several ways:
6491 the data type of the result is computed and recorded in it,
6492 warnings are generated if arg data types are invalid,
6493 special handling for addition and subtraction of pointers is known,
6494 and some optimization is done (operations on narrow ints
6495 are done in the narrower type when that gives the same result).
6496 Constant folding is also done before the result is returned.
6498 Note that the operands will never have enumeral types, or function
6499 or array types, because either they will have the default conversions
6500 performed or they have both just been converted to some other type in which
6501 the arithmetic is to be done. */
6504 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
6508 enum tree_code code0, code1;
6511 /* Expression code to give to the expression when it is built.
6512 Normally this is CODE, which is what the caller asked for,
6513 but in some special cases we change it. */
6514 enum tree_code resultcode = code;
6516 /* Data type in which the computation is to be performed.
6517 In the simplest cases this is the common type of the arguments. */
6518 tree result_type = NULL;
6520 /* Nonzero means operands have already been type-converted
6521 in whatever way is necessary.
6522 Zero means they need to be converted to RESULT_TYPE. */
6525 /* Nonzero means create the expression with this type, rather than
6527 tree build_type = 0;
6529 /* Nonzero means after finally constructing the expression
6530 convert it to this type. */
6531 tree final_type = 0;
6533 /* Nonzero if this is an operation like MIN or MAX which can
6534 safely be computed in short if both args are promoted shorts.
6535 Also implies COMMON.
6536 -1 indicates a bitwise operation; this makes a difference
6537 in the exact conditions for when it is safe to do the operation
6538 in a narrower mode. */
6541 /* Nonzero if this is a comparison operation;
6542 if both args are promoted shorts, compare the original shorts.
6543 Also implies COMMON. */
6544 int short_compare = 0;
6546 /* Nonzero if this is a right-shift operation, which can be computed on the
6547 original short and then promoted if the operand is a promoted short. */
6548 int short_shift = 0;
6550 /* Nonzero means set RESULT_TYPE to the common type of the args. */
6555 op0 = default_conversion (orig_op0);
6556 op1 = default_conversion (orig_op1);
6564 type0 = TREE_TYPE (op0);
6565 type1 = TREE_TYPE (op1);
6567 /* The expression codes of the data types of the arguments tell us
6568 whether the arguments are integers, floating, pointers, etc. */
6569 code0 = TREE_CODE (type0);
6570 code1 = TREE_CODE (type1);
6572 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
6573 STRIP_TYPE_NOPS (op0);
6574 STRIP_TYPE_NOPS (op1);
6576 /* If an error was already reported for one of the arguments,
6577 avoid reporting another error. */
6579 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
6580 return error_mark_node;
6585 /* Handle the pointer + int case. */
6586 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
6587 return pointer_int_sum (PLUS_EXPR, op0, op1);
6588 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
6589 return pointer_int_sum (PLUS_EXPR, op1, op0);
6595 /* Subtraction of two similar pointers.
6596 We must subtract them as integers, then divide by object size. */
6597 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
6598 && comp_target_types (type0, type1, 1))
6599 return pointer_diff (op0, op1);
6600 /* Handle pointer minus int. Just like pointer plus int. */
6601 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
6602 return pointer_int_sum (MINUS_EXPR, op0, op1);
6611 case TRUNC_DIV_EXPR:
6613 case FLOOR_DIV_EXPR:
6614 case ROUND_DIV_EXPR:
6615 case EXACT_DIV_EXPR:
6616 /* Floating point division by zero is a legitimate way to obtain
6617 infinities and NaNs. */
6618 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
6619 warning ("division by zero");
6621 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
6622 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
6623 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
6624 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
6626 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
6627 resultcode = RDIV_EXPR;
6629 /* Although it would be tempting to shorten always here, that
6630 loses on some targets, since the modulo instruction is
6631 undefined if the quotient can't be represented in the
6632 computation mode. We shorten only if unsigned or if
6633 dividing by something we know != -1. */
6634 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
6635 || (TREE_CODE (op1) == INTEGER_CST
6636 && ! integer_all_onesp (op1)));
6644 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
6646 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
6650 case TRUNC_MOD_EXPR:
6651 case FLOOR_MOD_EXPR:
6652 if (warn_div_by_zero && skip_evaluation == 0 && integer_zerop (op1))
6653 warning ("division by zero");
6655 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
6657 /* Although it would be tempting to shorten always here, that loses
6658 on some targets, since the modulo instruction is undefined if the
6659 quotient can't be represented in the computation mode. We shorten
6660 only if unsigned or if dividing by something we know != -1. */
6661 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
6662 || (TREE_CODE (op1) == INTEGER_CST
6663 && ! integer_all_onesp (op1)));
6668 case TRUTH_ANDIF_EXPR:
6669 case TRUTH_ORIF_EXPR:
6670 case TRUTH_AND_EXPR:
6672 case TRUTH_XOR_EXPR:
6673 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
6674 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
6675 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
6676 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
6678 /* Result of these operations is always an int,
6679 but that does not mean the operands should be
6680 converted to ints! */
6681 result_type = integer_type_node;
6682 op0 = lang_hooks.truthvalue_conversion (op0);
6683 op1 = lang_hooks.truthvalue_conversion (op1);
6688 /* Shift operations: result has same type as first operand;
6689 always convert second operand to int.
6690 Also set SHORT_SHIFT if shifting rightward. */
6693 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
6695 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
6697 if (tree_int_cst_sgn (op1) < 0)
6698 warning ("right shift count is negative");
6701 if (! integer_zerop (op1))
6704 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
6705 warning ("right shift count >= width of type");
6709 /* Use the type of the value to be shifted. */
6710 result_type = type0;
6711 /* Convert the shift-count to an integer, regardless of size
6712 of value being shifted. */
6713 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
6714 op1 = convert (integer_type_node, op1);
6715 /* Avoid converting op1 to result_type later. */
6721 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
6723 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
6725 if (tree_int_cst_sgn (op1) < 0)
6726 warning ("left shift count is negative");
6728 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
6729 warning ("left shift count >= width of type");
6732 /* Use the type of the value to be shifted. */
6733 result_type = type0;
6734 /* Convert the shift-count to an integer, regardless of size
6735 of value being shifted. */
6736 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
6737 op1 = convert (integer_type_node, op1);
6738 /* Avoid converting op1 to result_type later. */
6745 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
6747 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
6749 if (tree_int_cst_sgn (op1) < 0)
6750 warning ("shift count is negative");
6751 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
6752 warning ("shift count >= width of type");
6755 /* Use the type of the value to be shifted. */
6756 result_type = type0;
6757 /* Convert the shift-count to an integer, regardless of size
6758 of value being shifted. */
6759 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
6760 op1 = convert (integer_type_node, op1);
6761 /* Avoid converting op1 to result_type later. */
6768 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
6769 warning ("comparing floating point with == or != is unsafe");
6770 /* Result of comparison is always int,
6771 but don't convert the args to int! */
6772 build_type = integer_type_node;
6773 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
6774 || code0 == COMPLEX_TYPE)
6775 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
6776 || code1 == COMPLEX_TYPE))
6778 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
6780 tree tt0 = TREE_TYPE (type0);
6781 tree tt1 = TREE_TYPE (type1);
6782 /* Anything compares with void *. void * compares with anything.
6783 Otherwise, the targets must be compatible
6784 and both must be object or both incomplete. */
6785 if (comp_target_types (type0, type1, 1))
6786 result_type = common_pointer_type (type0, type1);
6787 else if (VOID_TYPE_P (tt0))
6789 /* op0 != orig_op0 detects the case of something
6790 whose value is 0 but which isn't a valid null ptr const. */
6791 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
6792 && TREE_CODE (tt1) == FUNCTION_TYPE)
6793 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
6795 else if (VOID_TYPE_P (tt1))
6797 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
6798 && TREE_CODE (tt0) == FUNCTION_TYPE)
6799 pedwarn ("ISO C forbids comparison of `void *' with function pointer");
6802 pedwarn ("comparison of distinct pointer types lacks a cast");
6804 if (result_type == NULL_TREE)
6805 result_type = ptr_type_node;
6807 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
6808 && integer_zerop (op1))
6809 result_type = type0;
6810 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
6811 && integer_zerop (op0))
6812 result_type = type1;
6813 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
6815 result_type = type0;
6816 pedwarn ("comparison between pointer and integer");
6818 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
6820 result_type = type1;
6821 pedwarn ("comparison between pointer and integer");
6827 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
6828 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
6830 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
6832 if (comp_target_types (type0, type1, 1))
6834 result_type = common_pointer_type (type0, type1);
6836 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
6837 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
6841 result_type = ptr_type_node;
6842 pedwarn ("comparison of distinct pointer types lacks a cast");
6851 build_type = integer_type_node;
6852 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
6853 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
6855 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
6857 if (comp_target_types (type0, type1, 1))
6859 result_type = common_pointer_type (type0, type1);
6860 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
6861 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
6862 pedwarn ("comparison of complete and incomplete pointers");
6864 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
6865 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
6869 result_type = ptr_type_node;
6870 pedwarn ("comparison of distinct pointer types lacks a cast");
6873 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
6874 && integer_zerop (op1))
6876 result_type = type0;
6877 if (pedantic || extra_warnings)
6878 pedwarn ("ordered comparison of pointer with integer zero");
6880 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
6881 && integer_zerop (op0))
6883 result_type = type1;
6885 pedwarn ("ordered comparison of pointer with integer zero");
6887 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
6889 result_type = type0;
6890 pedwarn ("comparison between pointer and integer");
6892 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
6894 result_type = type1;
6895 pedwarn ("comparison between pointer and integer");
6899 case UNORDERED_EXPR:
6907 build_type = integer_type_node;
6908 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
6910 error ("unordered comparison on non-floating point argument");
6911 return error_mark_node;
6920 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
6921 return error_mark_node;
6923 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
6924 || code0 == VECTOR_TYPE)
6926 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
6927 || code1 == VECTOR_TYPE))
6929 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
6931 if (shorten || common || short_compare)
6932 result_type = common_type (type0, type1);
6934 /* For certain operations (which identify themselves by shorten != 0)
6935 if both args were extended from the same smaller type,
6936 do the arithmetic in that type and then extend.
6938 shorten !=0 and !=1 indicates a bitwise operation.
6939 For them, this optimization is safe only if
6940 both args are zero-extended or both are sign-extended.
6941 Otherwise, we might change the result.
6942 Eg, (short)-1 | (unsigned short)-1 is (int)-1
6943 but calculated in (unsigned short) it would be (unsigned short)-1. */
6945 if (shorten && none_complex)
6947 int unsigned0, unsigned1;
6948 tree arg0 = get_narrower (op0, &unsigned0);
6949 tree arg1 = get_narrower (op1, &unsigned1);
6950 /* UNS is 1 if the operation to be done is an unsigned one. */
6951 int uns = TYPE_UNSIGNED (result_type);
6954 final_type = result_type;
6956 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
6957 but it *requires* conversion to FINAL_TYPE. */
6959 if ((TYPE_PRECISION (TREE_TYPE (op0))
6960 == TYPE_PRECISION (TREE_TYPE (arg0)))
6961 && TREE_TYPE (op0) != final_type)
6962 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
6963 if ((TYPE_PRECISION (TREE_TYPE (op1))
6964 == TYPE_PRECISION (TREE_TYPE (arg1)))
6965 && TREE_TYPE (op1) != final_type)
6966 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
6968 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
6970 /* For bitwise operations, signedness of nominal type
6971 does not matter. Consider only how operands were extended. */
6975 /* Note that in all three cases below we refrain from optimizing
6976 an unsigned operation on sign-extended args.
6977 That would not be valid. */
6979 /* Both args variable: if both extended in same way
6980 from same width, do it in that width.
6981 Do it unsigned if args were zero-extended. */
6982 if ((TYPE_PRECISION (TREE_TYPE (arg0))
6983 < TYPE_PRECISION (result_type))
6984 && (TYPE_PRECISION (TREE_TYPE (arg1))
6985 == TYPE_PRECISION (TREE_TYPE (arg0)))
6986 && unsigned0 == unsigned1
6987 && (unsigned0 || !uns))
6989 = c_common_signed_or_unsigned_type
6990 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
6991 else if (TREE_CODE (arg0) == INTEGER_CST
6992 && (unsigned1 || !uns)
6993 && (TYPE_PRECISION (TREE_TYPE (arg1))
6994 < TYPE_PRECISION (result_type))
6996 = c_common_signed_or_unsigned_type (unsigned1,
6998 int_fits_type_p (arg0, type)))
7000 else if (TREE_CODE (arg1) == INTEGER_CST
7001 && (unsigned0 || !uns)
7002 && (TYPE_PRECISION (TREE_TYPE (arg0))
7003 < TYPE_PRECISION (result_type))
7005 = c_common_signed_or_unsigned_type (unsigned0,
7007 int_fits_type_p (arg1, type)))
7011 /* Shifts can be shortened if shifting right. */
7016 tree arg0 = get_narrower (op0, &unsigned_arg);
7018 final_type = result_type;
7020 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7021 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7023 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7024 /* We can shorten only if the shift count is less than the
7025 number of bits in the smaller type size. */
7026 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7027 /* We cannot drop an unsigned shift after sign-extension. */
7028 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7030 /* Do an unsigned shift if the operand was zero-extended. */
7032 = c_common_signed_or_unsigned_type (unsigned_arg,
7034 /* Convert value-to-be-shifted to that type. */
7035 if (TREE_TYPE (op0) != result_type)
7036 op0 = convert (result_type, op0);
7041 /* Comparison operations are shortened too but differently.
7042 They identify themselves by setting short_compare = 1. */
7046 /* Don't write &op0, etc., because that would prevent op0
7047 from being kept in a register.
7048 Instead, make copies of the our local variables and
7049 pass the copies by reference, then copy them back afterward. */
7050 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7051 enum tree_code xresultcode = resultcode;
7053 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7058 op0 = xop0, op1 = xop1;
7060 resultcode = xresultcode;
7062 if (warn_sign_compare && skip_evaluation == 0)
7064 int op0_signed = ! TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7065 int op1_signed = ! TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7066 int unsignedp0, unsignedp1;
7067 tree primop0 = get_narrower (op0, &unsignedp0);
7068 tree primop1 = get_narrower (op1, &unsignedp1);
7072 STRIP_TYPE_NOPS (xop0);
7073 STRIP_TYPE_NOPS (xop1);
7075 /* Give warnings for comparisons between signed and unsigned
7076 quantities that may fail.
7078 Do the checking based on the original operand trees, so that
7079 casts will be considered, but default promotions won't be.
7081 Do not warn if the comparison is being done in a signed type,
7082 since the signed type will only be chosen if it can represent
7083 all the values of the unsigned type. */
7084 if (! TYPE_UNSIGNED (result_type))
7086 /* Do not warn if both operands are the same signedness. */
7087 else if (op0_signed == op1_signed)
7094 sop = xop0, uop = xop1;
7096 sop = xop1, uop = xop0;
7098 /* Do not warn if the signed quantity is an
7099 unsuffixed integer literal (or some static
7100 constant expression involving such literals or a
7101 conditional expression involving such literals)
7102 and it is non-negative. */
7103 if (c_tree_expr_nonnegative_p (sop))
7105 /* Do not warn if the comparison is an equality operation,
7106 the unsigned quantity is an integral constant, and it
7107 would fit in the result if the result were signed. */
7108 else if (TREE_CODE (uop) == INTEGER_CST
7109 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
7111 (uop, c_common_signed_type (result_type)))
7113 /* Do not warn if the unsigned quantity is an enumeration
7114 constant and its maximum value would fit in the result
7115 if the result were signed. */
7116 else if (TREE_CODE (uop) == INTEGER_CST
7117 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
7119 (TYPE_MAX_VALUE (TREE_TYPE(uop)),
7120 c_common_signed_type (result_type)))
7123 warning ("comparison between signed and unsigned");
7126 /* Warn if two unsigned values are being compared in a size
7127 larger than their original size, and one (and only one) is the
7128 result of a `~' operator. This comparison will always fail.
7130 Also warn if one operand is a constant, and the constant
7131 does not have all bits set that are set in the ~ operand
7132 when it is extended. */
7134 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
7135 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
7137 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
7138 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
7141 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
7144 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
7147 HOST_WIDE_INT constant, mask;
7148 int unsignedp, bits;
7150 if (host_integerp (primop0, 0))
7153 unsignedp = unsignedp1;
7154 constant = tree_low_cst (primop0, 0);
7159 unsignedp = unsignedp0;
7160 constant = tree_low_cst (primop1, 0);
7163 bits = TYPE_PRECISION (TREE_TYPE (primop));
7164 if (bits < TYPE_PRECISION (result_type)
7165 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
7167 mask = (~ (HOST_WIDE_INT) 0) << bits;
7168 if ((mask & constant) != mask)
7169 warning ("comparison of promoted ~unsigned with constant");
7172 else if (unsignedp0 && unsignedp1
7173 && (TYPE_PRECISION (TREE_TYPE (primop0))
7174 < TYPE_PRECISION (result_type))
7175 && (TYPE_PRECISION (TREE_TYPE (primop1))
7176 < TYPE_PRECISION (result_type)))
7177 warning ("comparison of promoted ~unsigned with unsigned");
7183 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
7184 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
7185 Then the expression will be built.
7186 It will be given type FINAL_TYPE if that is nonzero;
7187 otherwise, it will be given type RESULT_TYPE. */
7191 binary_op_error (code);
7192 return error_mark_node;
7197 if (TREE_TYPE (op0) != result_type)
7198 op0 = convert (result_type, op0);
7199 if (TREE_TYPE (op1) != result_type)
7200 op1 = convert (result_type, op1);
7203 if (build_type == NULL_TREE)
7204 build_type = result_type;
7207 tree result = build (resultcode, build_type, op0, op1);
7209 /* Treat expressions in initializers specially as they can't trap. */
7210 result = require_constant_value ? fold_initializer (result)
7213 if (final_type != 0)
7214 result = convert (final_type, result);
7219 /* Build the result of __builtin_offsetof. TYPE is the first argument to
7220 offsetof, i.e. a type. LIST is a tree_list that encodes component and
7221 array references; PURPOSE is set for the former and VALUE is set for
7225 build_offsetof (tree type, tree list)
7229 /* Build "*(type *)0". */
7230 t = convert (build_pointer_type (type), null_pointer_node);
7231 t = build_indirect_ref (t, "");
7233 /* Build COMPONENT and ARRAY_REF expressions as needed. */
7234 for (list = nreverse (list); list ; list = TREE_CHAIN (list))
7235 if (TREE_PURPOSE (list))
7236 t = build_component_ref (t, TREE_PURPOSE (list));
7238 t = build_array_ref (t, TREE_VALUE (list));
7240 /* Finalize the offsetof expression. For now all we need to do is take
7241 the address of the expression we created, and cast that to an integer
7242 type; this mirrors the traditional macro implementation of offsetof. */
7243 t = build_unary_op (ADDR_EXPR, t, 0);
7244 return convert (size_type_node, t);