1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization. */
30 #include "coretypes.h"
34 #include "langhooks.h"
44 #include "tree-iterator.h"
45 #include "tree-gimple.h"
46 #include "tree-flow.h"
48 /* Possible cases of implicit bad conversions. Used to select
49 diagnostic messages in convert_for_assignment. */
58 /* The level of nesting inside "__alignof__". */
61 /* The level of nesting inside "sizeof". */
64 /* The level of nesting inside "typeof". */
67 struct c_label_context_se *label_context_stack_se;
68 struct c_label_context_vm *label_context_stack_vm;
70 /* Nonzero if we've already printed a "missing braces around initializer"
71 message within this initializer. */
72 static int missing_braces_mentioned;
74 static int require_constant_value;
75 static int require_constant_elements;
77 static tree qualify_type (tree, tree);
78 static int tagged_types_tu_compatible_p (tree, tree);
79 static int comp_target_types (tree, tree);
80 static int function_types_compatible_p (tree, tree);
81 static int type_lists_compatible_p (tree, tree);
82 static tree decl_constant_value_for_broken_optimization (tree);
83 static tree lookup_field (tree, tree);
84 static tree convert_arguments (tree, tree, tree, tree);
85 static tree pointer_diff (tree, tree);
86 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
88 static tree valid_compound_expr_initializer (tree, tree);
89 static void push_string (const char *);
90 static void push_member_name (tree);
91 static void push_array_bounds (int);
92 static int spelling_length (void);
93 static char *print_spelling (char *);
94 static void warning_init (const char *);
95 static tree digest_init (tree, tree, bool, int);
96 static void output_init_element (tree, bool, tree, tree, int);
97 static void output_pending_init_elements (int);
98 static int set_designator (int);
99 static void push_range_stack (tree);
100 static void add_pending_init (tree, tree);
101 static void set_nonincremental_init (void);
102 static void set_nonincremental_init_from_string (tree);
103 static tree find_init_member (tree);
104 static void readonly_error (tree, enum lvalue_use);
105 static int lvalue_or_else (tree, enum lvalue_use);
106 static int lvalue_p (tree);
107 static void record_maybe_used_decl (tree);
109 /* Do `exp = require_complete_type (exp);' to make sure exp
110 does not have an incomplete type. (That includes void types.) */
113 require_complete_type (tree value)
115 tree type = TREE_TYPE (value);
117 if (value == error_mark_node || type == error_mark_node)
118 return error_mark_node;
120 /* First, detect a valid value with a complete type. */
121 if (COMPLETE_TYPE_P (type))
124 c_incomplete_type_error (value, type);
125 return error_mark_node;
128 /* Print an error message for invalid use of an incomplete type.
129 VALUE is the expression that was used (or 0 if that isn't known)
130 and TYPE is the type that was invalid. */
133 c_incomplete_type_error (tree value, tree type)
135 const char *type_code_string;
137 /* Avoid duplicate error message. */
138 if (TREE_CODE (type) == ERROR_MARK)
141 if (value != 0 && (TREE_CODE (value) == VAR_DECL
142 || TREE_CODE (value) == PARM_DECL))
143 error ("%qD has an incomplete type", value);
147 /* We must print an error message. Be clever about what it says. */
149 switch (TREE_CODE (type))
152 type_code_string = "struct";
156 type_code_string = "union";
160 type_code_string = "enum";
164 error ("invalid use of void expression");
168 if (TYPE_DOMAIN (type))
170 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
172 error ("invalid use of flexible array member");
175 type = TREE_TYPE (type);
178 error ("invalid use of array with unspecified bounds");
185 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
186 error ("invalid use of undefined type %<%s %E%>",
187 type_code_string, TYPE_NAME (type));
189 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
190 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
194 /* Given a type, apply default promotions wrt unnamed function
195 arguments and return the new type. */
198 c_type_promotes_to (tree type)
200 if (TYPE_MAIN_VARIANT (type) == float_type_node)
201 return double_type_node;
203 if (c_promoting_integer_type_p (type))
205 /* Preserve unsignedness if not really getting any wider. */
206 if (TYPE_UNSIGNED (type)
207 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
208 return unsigned_type_node;
209 return integer_type_node;
215 /* Return a variant of TYPE which has all the type qualifiers of LIKE
216 as well as those of TYPE. */
219 qualify_type (tree type, tree like)
221 return c_build_qualified_type (type,
222 TYPE_QUALS (type) | TYPE_QUALS (like));
225 /* Return the composite type of two compatible types.
227 We assume that comptypes has already been done and returned
228 nonzero; if that isn't so, this may crash. In particular, we
229 assume that qualifiers match. */
232 composite_type (tree t1, tree t2)
234 enum tree_code code1;
235 enum tree_code code2;
238 /* Save time if the two types are the same. */
240 if (t1 == t2) return t1;
242 /* If one type is nonsense, use the other. */
243 if (t1 == error_mark_node)
245 if (t2 == error_mark_node)
248 code1 = TREE_CODE (t1);
249 code2 = TREE_CODE (t2);
251 /* Merge the attributes. */
252 attributes = targetm.merge_type_attributes (t1, t2);
254 /* If one is an enumerated type and the other is the compatible
255 integer type, the composite type might be either of the two
256 (DR#013 question 3). For consistency, use the enumerated type as
257 the composite type. */
259 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
261 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
264 gcc_assert (code1 == code2);
269 /* For two pointers, do this recursively on the target type. */
271 tree pointed_to_1 = TREE_TYPE (t1);
272 tree pointed_to_2 = TREE_TYPE (t2);
273 tree target = composite_type (pointed_to_1, pointed_to_2);
274 t1 = build_pointer_type (target);
275 t1 = build_type_attribute_variant (t1, attributes);
276 return qualify_type (t1, t2);
281 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
285 /* We should not have any type quals on arrays at all. */
286 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
288 /* Save space: see if the result is identical to one of the args. */
289 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
290 return build_type_attribute_variant (t1, attributes);
291 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
292 return build_type_attribute_variant (t2, attributes);
294 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
295 return build_type_attribute_variant (t1, attributes);
296 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
297 return build_type_attribute_variant (t2, attributes);
299 /* Merge the element types, and have a size if either arg has
300 one. We may have qualifiers on the element types. To set
301 up TYPE_MAIN_VARIANT correctly, we need to form the
302 composite of the unqualified types and add the qualifiers
304 quals = TYPE_QUALS (strip_array_types (elt));
305 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
306 t1 = build_array_type (unqual_elt,
307 TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
308 t1 = c_build_qualified_type (t1, quals);
309 return build_type_attribute_variant (t1, attributes);
313 /* Function types: prefer the one that specified arg types.
314 If both do, merge the arg types. Also merge the return types. */
316 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
317 tree p1 = TYPE_ARG_TYPES (t1);
318 tree p2 = TYPE_ARG_TYPES (t2);
323 /* Save space: see if the result is identical to one of the args. */
324 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
325 return build_type_attribute_variant (t1, attributes);
326 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
327 return build_type_attribute_variant (t2, attributes);
329 /* Simple way if one arg fails to specify argument types. */
330 if (TYPE_ARG_TYPES (t1) == 0)
332 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
333 t1 = build_type_attribute_variant (t1, attributes);
334 return qualify_type (t1, t2);
336 if (TYPE_ARG_TYPES (t2) == 0)
338 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
339 t1 = build_type_attribute_variant (t1, attributes);
340 return qualify_type (t1, t2);
343 /* If both args specify argument types, we must merge the two
344 lists, argument by argument. */
345 /* Tell global_bindings_p to return false so that variable_size
346 doesn't die on VLAs in parameter types. */
347 c_override_global_bindings_to_false = true;
349 len = list_length (p1);
352 for (i = 0; i < len; i++)
353 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
358 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
360 /* A null type means arg type is not specified.
361 Take whatever the other function type has. */
362 if (TREE_VALUE (p1) == 0)
364 TREE_VALUE (n) = TREE_VALUE (p2);
367 if (TREE_VALUE (p2) == 0)
369 TREE_VALUE (n) = TREE_VALUE (p1);
373 /* Given wait (union {union wait *u; int *i} *)
374 and wait (union wait *),
375 prefer union wait * as type of parm. */
376 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
377 && TREE_VALUE (p1) != TREE_VALUE (p2))
380 tree mv2 = TREE_VALUE (p2);
381 if (mv2 && mv2 != error_mark_node
382 && TREE_CODE (mv2) != ARRAY_TYPE)
383 mv2 = TYPE_MAIN_VARIANT (mv2);
384 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
385 memb; memb = TREE_CHAIN (memb))
387 tree mv3 = TREE_TYPE (memb);
388 if (mv3 && mv3 != error_mark_node
389 && TREE_CODE (mv3) != ARRAY_TYPE)
390 mv3 = TYPE_MAIN_VARIANT (mv3);
391 if (comptypes (mv3, mv2))
393 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
396 pedwarn ("function types not truly compatible in ISO C");
401 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
402 && TREE_VALUE (p2) != TREE_VALUE (p1))
405 tree mv1 = TREE_VALUE (p1);
406 if (mv1 && mv1 != error_mark_node
407 && TREE_CODE (mv1) != ARRAY_TYPE)
408 mv1 = TYPE_MAIN_VARIANT (mv1);
409 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
410 memb; memb = TREE_CHAIN (memb))
412 tree mv3 = TREE_TYPE (memb);
413 if (mv3 && mv3 != error_mark_node
414 && TREE_CODE (mv3) != ARRAY_TYPE)
415 mv3 = TYPE_MAIN_VARIANT (mv3);
416 if (comptypes (mv3, mv1))
418 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
421 pedwarn ("function types not truly compatible in ISO C");
426 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
430 c_override_global_bindings_to_false = false;
431 t1 = build_function_type (valtype, newargs);
432 t1 = qualify_type (t1, t2);
433 /* ... falls through ... */
437 return build_type_attribute_variant (t1, attributes);
442 /* Return the type of a conditional expression between pointers to
443 possibly differently qualified versions of compatible types.
445 We assume that comp_target_types has already been done and returned
446 nonzero; if that isn't so, this may crash. */
449 common_pointer_type (tree t1, tree t2)
452 tree pointed_to_1, mv1;
453 tree pointed_to_2, mv2;
456 /* Save time if the two types are the same. */
458 if (t1 == t2) return t1;
460 /* If one type is nonsense, use the other. */
461 if (t1 == error_mark_node)
463 if (t2 == error_mark_node)
466 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
467 && TREE_CODE (t2) == POINTER_TYPE);
469 /* Merge the attributes. */
470 attributes = targetm.merge_type_attributes (t1, t2);
472 /* Find the composite type of the target types, and combine the
473 qualifiers of the two types' targets. Do not lose qualifiers on
474 array element types by taking the TYPE_MAIN_VARIANT. */
475 mv1 = pointed_to_1 = TREE_TYPE (t1);
476 mv2 = pointed_to_2 = TREE_TYPE (t2);
477 if (TREE_CODE (mv1) != ARRAY_TYPE)
478 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
479 if (TREE_CODE (mv2) != ARRAY_TYPE)
480 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
481 target = composite_type (mv1, mv2);
482 t1 = build_pointer_type (c_build_qualified_type
484 TYPE_QUALS (pointed_to_1) |
485 TYPE_QUALS (pointed_to_2)));
486 return build_type_attribute_variant (t1, attributes);
489 /* Return the common type for two arithmetic types under the usual
490 arithmetic conversions. The default conversions have already been
491 applied, and enumerated types converted to their compatible integer
492 types. The resulting type is unqualified and has no attributes.
494 This is the type for the result of most arithmetic operations
495 if the operands have the given two types. */
498 c_common_type (tree t1, tree t2)
500 enum tree_code code1;
501 enum tree_code code2;
503 /* If one type is nonsense, use the other. */
504 if (t1 == error_mark_node)
506 if (t2 == error_mark_node)
509 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
510 t1 = TYPE_MAIN_VARIANT (t1);
512 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
513 t2 = TYPE_MAIN_VARIANT (t2);
515 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
516 t1 = build_type_attribute_variant (t1, NULL_TREE);
518 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
519 t2 = build_type_attribute_variant (t2, NULL_TREE);
521 /* Save time if the two types are the same. */
523 if (t1 == t2) return t1;
525 code1 = TREE_CODE (t1);
526 code2 = TREE_CODE (t2);
528 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
529 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
530 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
531 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
533 /* If one type is a vector type, return that type. (How the usual
534 arithmetic conversions apply to the vector types extension is not
535 precisely specified.) */
536 if (code1 == VECTOR_TYPE)
539 if (code2 == VECTOR_TYPE)
542 /* If one type is complex, form the common type of the non-complex
543 components, then make that complex. Use T1 or T2 if it is the
545 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
547 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
548 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
549 tree subtype = c_common_type (subtype1, subtype2);
551 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
553 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
556 return build_complex_type (subtype);
559 /* If only one is real, use it as the result. */
561 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
564 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
567 /* Both real or both integers; use the one with greater precision. */
569 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
571 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
574 /* Same precision. Prefer long longs to longs to ints when the
575 same precision, following the C99 rules on integer type rank
576 (which are equivalent to the C90 rules for C90 types). */
578 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
579 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
580 return long_long_unsigned_type_node;
582 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
583 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
585 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
586 return long_long_unsigned_type_node;
588 return long_long_integer_type_node;
591 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
592 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
593 return long_unsigned_type_node;
595 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
596 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
598 /* But preserve unsignedness from the other type,
599 since long cannot hold all the values of an unsigned int. */
600 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
601 return long_unsigned_type_node;
603 return long_integer_type_node;
606 /* Likewise, prefer long double to double even if same size. */
607 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
608 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
609 return long_double_type_node;
611 /* Otherwise prefer the unsigned one. */
613 if (TYPE_UNSIGNED (t1))
619 /* Wrapper around c_common_type that is used by c-common.c. ENUMERAL_TYPEs
620 are allowed here and are converted to their compatible integer types.
621 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
622 preferably a non-Boolean type as the common type. */
624 common_type (tree t1, tree t2)
626 if (TREE_CODE (t1) == ENUMERAL_TYPE)
627 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
628 if (TREE_CODE (t2) == ENUMERAL_TYPE)
629 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
631 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
632 if (TREE_CODE (t1) == BOOLEAN_TYPE
633 && TREE_CODE (t2) == BOOLEAN_TYPE)
634 return boolean_type_node;
636 /* If either type is BOOLEAN_TYPE, then return the other. */
637 if (TREE_CODE (t1) == BOOLEAN_TYPE)
639 if (TREE_CODE (t2) == BOOLEAN_TYPE)
642 return c_common_type (t1, t2);
645 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
646 or various other operations. Return 2 if they are compatible
647 but a warning may be needed if you use them together. */
650 comptypes (tree type1, tree type2)
656 /* Suppress errors caused by previously reported errors. */
658 if (t1 == t2 || !t1 || !t2
659 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
662 /* If either type is the internal version of sizetype, return the
664 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
665 && TYPE_ORIG_SIZE_TYPE (t1))
666 t1 = TYPE_ORIG_SIZE_TYPE (t1);
668 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
669 && TYPE_ORIG_SIZE_TYPE (t2))
670 t2 = TYPE_ORIG_SIZE_TYPE (t2);
673 /* Enumerated types are compatible with integer types, but this is
674 not transitive: two enumerated types in the same translation unit
675 are compatible with each other only if they are the same type. */
677 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
678 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
679 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
680 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
685 /* Different classes of types can't be compatible. */
687 if (TREE_CODE (t1) != TREE_CODE (t2))
690 /* Qualifiers must match. C99 6.7.3p9 */
692 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
695 /* Allow for two different type nodes which have essentially the same
696 definition. Note that we already checked for equality of the type
697 qualifiers (just above). */
699 if (TREE_CODE (t1) != ARRAY_TYPE
700 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
703 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
704 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
707 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
710 switch (TREE_CODE (t1))
713 /* Do not remove mode or aliasing information. */
714 if (TYPE_MODE (t1) != TYPE_MODE (t2)
715 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
717 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
718 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
722 val = function_types_compatible_p (t1, t2);
727 tree d1 = TYPE_DOMAIN (t1);
728 tree d2 = TYPE_DOMAIN (t2);
729 bool d1_variable, d2_variable;
730 bool d1_zero, d2_zero;
733 /* Target types must match incl. qualifiers. */
734 if (TREE_TYPE (t1) != TREE_TYPE (t2)
735 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
738 /* Sizes must match unless one is missing or variable. */
739 if (d1 == 0 || d2 == 0 || d1 == d2)
742 d1_zero = !TYPE_MAX_VALUE (d1);
743 d2_zero = !TYPE_MAX_VALUE (d2);
745 d1_variable = (!d1_zero
746 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
747 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
748 d2_variable = (!d2_zero
749 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
750 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
752 if (d1_variable || d2_variable)
754 if (d1_zero && d2_zero)
756 if (d1_zero || d2_zero
757 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
758 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
767 if (val != 1 && !same_translation_unit_p (t1, t2))
768 val = tagged_types_tu_compatible_p (t1, t2);
772 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
773 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2));
779 return attrval == 2 && val == 1 ? 2 : val;
782 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
783 ignoring their qualifiers. */
786 comp_target_types (tree ttl, tree ttr)
791 /* Do not lose qualifiers on element types of array types that are
792 pointer targets by taking their TYPE_MAIN_VARIANT. */
793 mvl = TREE_TYPE (ttl);
794 mvr = TREE_TYPE (ttr);
795 if (TREE_CODE (mvl) != ARRAY_TYPE)
796 mvl = TYPE_MAIN_VARIANT (mvl);
797 if (TREE_CODE (mvr) != ARRAY_TYPE)
798 mvr = TYPE_MAIN_VARIANT (mvr);
799 val = comptypes (mvl, mvr);
801 if (val == 2 && pedantic)
802 pedwarn ("types are not quite compatible");
806 /* Subroutines of `comptypes'. */
808 /* Determine whether two trees derive from the same translation unit.
809 If the CONTEXT chain ends in a null, that tree's context is still
810 being parsed, so if two trees have context chains ending in null,
811 they're in the same translation unit. */
813 same_translation_unit_p (tree t1, tree t2)
815 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
816 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
818 case tcc_declaration:
819 t1 = DECL_CONTEXT (t1); break;
821 t1 = TYPE_CONTEXT (t1); break;
822 case tcc_exceptional:
823 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
824 default: gcc_unreachable ();
827 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
828 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
830 case tcc_declaration:
831 t2 = DECL_CONTEXT (t2); break;
833 t2 = TYPE_CONTEXT (t2); break;
834 case tcc_exceptional:
835 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
836 default: gcc_unreachable ();
842 /* The C standard says that two structures in different translation
843 units are compatible with each other only if the types of their
844 fields are compatible (among other things). So, consider two copies
845 of this structure: */
847 struct tagged_tu_seen {
848 const struct tagged_tu_seen * next;
853 /* Can they be compatible with each other? We choose to break the
854 recursion by allowing those types to be compatible. */
856 static const struct tagged_tu_seen * tagged_tu_seen_base;
858 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
859 compatible. If the two types are not the same (which has been
860 checked earlier), this can only happen when multiple translation
861 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
865 tagged_types_tu_compatible_p (tree t1, tree t2)
868 bool needs_warning = false;
870 /* We have to verify that the tags of the types are the same. This
871 is harder than it looks because this may be a typedef, so we have
872 to go look at the original type. It may even be a typedef of a
874 In the case of compiler-created builtin structs the TYPE_DECL
875 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
876 while (TYPE_NAME (t1)
877 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
878 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
879 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
881 while (TYPE_NAME (t2)
882 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
883 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
884 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
886 /* C90 didn't have the requirement that the two tags be the same. */
887 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
890 /* C90 didn't say what happened if one or both of the types were
891 incomplete; we choose to follow C99 rules here, which is that they
893 if (TYPE_SIZE (t1) == NULL
894 || TYPE_SIZE (t2) == NULL)
898 const struct tagged_tu_seen * tts_i;
899 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
900 if (tts_i->t1 == t1 && tts_i->t2 == t2)
904 switch (TREE_CODE (t1))
909 /* Speed up the case where the type values are in the same order. */
910 tree tv1 = TYPE_VALUES (t1);
911 tree tv2 = TYPE_VALUES (t2);
916 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
918 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
920 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
924 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
926 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
929 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
932 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
934 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
936 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
944 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
947 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
950 struct tagged_tu_seen tts;
952 tts.next = tagged_tu_seen_base;
955 tagged_tu_seen_base = &tts;
957 if (DECL_NAME (s1) != NULL)
958 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
959 if (DECL_NAME (s1) == DECL_NAME (s2))
962 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
966 needs_warning = true;
968 if (TREE_CODE (s1) == FIELD_DECL
969 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
970 DECL_FIELD_BIT_OFFSET (s2)) != 1)
976 tagged_tu_seen_base = tts.next;
980 return needs_warning ? 2 : 1;
985 struct tagged_tu_seen tts;
987 tts.next = tagged_tu_seen_base;
990 tagged_tu_seen_base = &tts;
992 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
994 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
997 if (TREE_CODE (s1) != TREE_CODE (s2)
998 || DECL_NAME (s1) != DECL_NAME (s2))
1000 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
1004 needs_warning = true;
1006 if (TREE_CODE (s1) == FIELD_DECL
1007 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1008 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1011 tagged_tu_seen_base = tts.next;
1014 return needs_warning ? 2 : 1;
1022 /* Return 1 if two function types F1 and F2 are compatible.
1023 If either type specifies no argument types,
1024 the other must specify a fixed number of self-promoting arg types.
1025 Otherwise, if one type specifies only the number of arguments,
1026 the other must specify that number of self-promoting arg types.
1027 Otherwise, the argument types must match. */
1030 function_types_compatible_p (tree f1, tree f2)
1033 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1038 ret1 = TREE_TYPE (f1);
1039 ret2 = TREE_TYPE (f2);
1041 /* 'volatile' qualifiers on a function's return type used to mean
1042 the function is noreturn. */
1043 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1044 pedwarn ("function return types not compatible due to %<volatile%>");
1045 if (TYPE_VOLATILE (ret1))
1046 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1047 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1048 if (TYPE_VOLATILE (ret2))
1049 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1050 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1051 val = comptypes (ret1, ret2);
1055 args1 = TYPE_ARG_TYPES (f1);
1056 args2 = TYPE_ARG_TYPES (f2);
1058 /* An unspecified parmlist matches any specified parmlist
1059 whose argument types don't need default promotions. */
1063 if (!self_promoting_args_p (args2))
1065 /* If one of these types comes from a non-prototype fn definition,
1066 compare that with the other type's arglist.
1067 If they don't match, ask for a warning (but no error). */
1068 if (TYPE_ACTUAL_ARG_TYPES (f1)
1069 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1075 if (!self_promoting_args_p (args1))
1077 if (TYPE_ACTUAL_ARG_TYPES (f2)
1078 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1083 /* Both types have argument lists: compare them and propagate results. */
1084 val1 = type_lists_compatible_p (args1, args2);
1085 return val1 != 1 ? val1 : val;
1088 /* Check two lists of types for compatibility,
1089 returning 0 for incompatible, 1 for compatible,
1090 or 2 for compatible with warning. */
1093 type_lists_compatible_p (tree args1, tree args2)
1095 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1101 tree a1, mv1, a2, mv2;
1102 if (args1 == 0 && args2 == 0)
1104 /* If one list is shorter than the other,
1105 they fail to match. */
1106 if (args1 == 0 || args2 == 0)
1108 mv1 = a1 = TREE_VALUE (args1);
1109 mv2 = a2 = TREE_VALUE (args2);
1110 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1111 mv1 = TYPE_MAIN_VARIANT (mv1);
1112 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1113 mv2 = TYPE_MAIN_VARIANT (mv2);
1114 /* A null pointer instead of a type
1115 means there is supposed to be an argument
1116 but nothing is specified about what type it has.
1117 So match anything that self-promotes. */
1120 if (c_type_promotes_to (a2) != a2)
1125 if (c_type_promotes_to (a1) != a1)
1128 /* If one of the lists has an error marker, ignore this arg. */
1129 else if (TREE_CODE (a1) == ERROR_MARK
1130 || TREE_CODE (a2) == ERROR_MARK)
1132 else if (!(newval = comptypes (mv1, mv2)))
1134 /* Allow wait (union {union wait *u; int *i} *)
1135 and wait (union wait *) to be compatible. */
1136 if (TREE_CODE (a1) == UNION_TYPE
1137 && (TYPE_NAME (a1) == 0
1138 || TYPE_TRANSPARENT_UNION (a1))
1139 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1140 && tree_int_cst_equal (TYPE_SIZE (a1),
1144 for (memb = TYPE_FIELDS (a1);
1145 memb; memb = TREE_CHAIN (memb))
1147 tree mv3 = TREE_TYPE (memb);
1148 if (mv3 && mv3 != error_mark_node
1149 && TREE_CODE (mv3) != ARRAY_TYPE)
1150 mv3 = TYPE_MAIN_VARIANT (mv3);
1151 if (comptypes (mv3, mv2))
1157 else if (TREE_CODE (a2) == UNION_TYPE
1158 && (TYPE_NAME (a2) == 0
1159 || TYPE_TRANSPARENT_UNION (a2))
1160 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1161 && tree_int_cst_equal (TYPE_SIZE (a2),
1165 for (memb = TYPE_FIELDS (a2);
1166 memb; memb = TREE_CHAIN (memb))
1168 tree mv3 = TREE_TYPE (memb);
1169 if (mv3 && mv3 != error_mark_node
1170 && TREE_CODE (mv3) != ARRAY_TYPE)
1171 mv3 = TYPE_MAIN_VARIANT (mv3);
1172 if (comptypes (mv3, mv1))
1182 /* comptypes said ok, but record if it said to warn. */
1186 args1 = TREE_CHAIN (args1);
1187 args2 = TREE_CHAIN (args2);
1191 /* Compute the size to increment a pointer by. */
1194 c_size_in_bytes (tree type)
1196 enum tree_code code = TREE_CODE (type);
1198 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1199 return size_one_node;
1201 if (!COMPLETE_OR_VOID_TYPE_P (type))
1203 error ("arithmetic on pointer to an incomplete type");
1204 return size_one_node;
1207 /* Convert in case a char is more than one unit. */
1208 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1209 size_int (TYPE_PRECISION (char_type_node)
1213 /* Return either DECL or its known constant value (if it has one). */
1216 decl_constant_value (tree decl)
1218 if (/* Don't change a variable array bound or initial value to a constant
1219 in a place where a variable is invalid. Note that DECL_INITIAL
1220 isn't valid for a PARM_DECL. */
1221 current_function_decl != 0
1222 && TREE_CODE (decl) != PARM_DECL
1223 && !TREE_THIS_VOLATILE (decl)
1224 && TREE_READONLY (decl)
1225 && DECL_INITIAL (decl) != 0
1226 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1227 /* This is invalid if initial value is not constant.
1228 If it has either a function call, a memory reference,
1229 or a variable, then re-evaluating it could give different results. */
1230 && TREE_CONSTANT (DECL_INITIAL (decl))
1231 /* Check for cases where this is sub-optimal, even though valid. */
1232 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1233 return DECL_INITIAL (decl);
1237 /* Return either DECL or its known constant value (if it has one), but
1238 return DECL if pedantic or DECL has mode BLKmode. This is for
1239 bug-compatibility with the old behavior of decl_constant_value
1240 (before GCC 3.0); every use of this function is a bug and it should
1241 be removed before GCC 3.1. It is not appropriate to use pedantic
1242 in a way that affects optimization, and BLKmode is probably not the
1243 right test for avoiding misoptimizations either. */
1246 decl_constant_value_for_broken_optimization (tree decl)
1250 if (pedantic || DECL_MODE (decl) == BLKmode)
1253 ret = decl_constant_value (decl);
1254 /* Avoid unwanted tree sharing between the initializer and current
1255 function's body where the tree can be modified e.g. by the
1257 if (ret != decl && TREE_STATIC (decl))
1258 ret = unshare_expr (ret);
1262 /* Convert the array expression EXP to a pointer. */
1264 array_to_pointer_conversion (tree exp)
1266 tree orig_exp = exp;
1267 tree type = TREE_TYPE (exp);
1269 tree restype = TREE_TYPE (type);
1272 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1274 STRIP_TYPE_NOPS (exp);
1276 if (TREE_NO_WARNING (orig_exp))
1277 TREE_NO_WARNING (exp) = 1;
1279 ptrtype = build_pointer_type (restype);
1281 if (TREE_CODE (exp) == INDIRECT_REF)
1282 return convert (ptrtype, TREE_OPERAND (exp, 0));
1284 if (TREE_CODE (exp) == VAR_DECL)
1286 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1287 ADDR_EXPR because it's the best way of representing what
1288 happens in C when we take the address of an array and place
1289 it in a pointer to the element type. */
1290 adr = build1 (ADDR_EXPR, ptrtype, exp);
1291 if (!c_mark_addressable (exp))
1292 return error_mark_node;
1293 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1297 /* This way is better for a COMPONENT_REF since it can
1298 simplify the offset for a component. */
1299 adr = build_unary_op (ADDR_EXPR, exp, 1);
1300 return convert (ptrtype, adr);
1303 /* Convert the function expression EXP to a pointer. */
1305 function_to_pointer_conversion (tree exp)
1307 tree orig_exp = exp;
1309 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1311 STRIP_TYPE_NOPS (exp);
1313 if (TREE_NO_WARNING (orig_exp))
1314 TREE_NO_WARNING (exp) = 1;
1316 return build_unary_op (ADDR_EXPR, exp, 0);
1319 /* Perform the default conversion of arrays and functions to pointers.
1320 Return the result of converting EXP. For any other expression, just
1321 return EXP after removing NOPs. */
1324 default_function_array_conversion (struct c_expr exp)
1326 tree orig_exp = exp.value;
1327 tree type = TREE_TYPE (exp.value);
1328 enum tree_code code = TREE_CODE (type);
1334 bool not_lvalue = false;
1335 bool lvalue_array_p;
1337 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1338 || TREE_CODE (exp.value) == NOP_EXPR)
1339 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1341 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1343 exp.value = TREE_OPERAND (exp.value, 0);
1346 if (TREE_NO_WARNING (orig_exp))
1347 TREE_NO_WARNING (exp.value) = 1;
1349 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1350 if (!flag_isoc99 && !lvalue_array_p)
1352 /* Before C99, non-lvalue arrays do not decay to pointers.
1353 Normally, using such an array would be invalid; but it can
1354 be used correctly inside sizeof or as a statement expression.
1355 Thus, do not give an error here; an error will result later. */
1359 exp.value = array_to_pointer_conversion (exp.value);
1363 exp.value = function_to_pointer_conversion (exp.value);
1366 STRIP_TYPE_NOPS (exp.value);
1367 if (TREE_NO_WARNING (orig_exp))
1368 TREE_NO_WARNING (exp.value) = 1;
1376 /* EXP is an expression of integer type. Apply the integer promotions
1377 to it and return the promoted value. */
1380 perform_integral_promotions (tree exp)
1382 tree type = TREE_TYPE (exp);
1383 enum tree_code code = TREE_CODE (type);
1385 gcc_assert (INTEGRAL_TYPE_P (type));
1387 /* Normally convert enums to int,
1388 but convert wide enums to something wider. */
1389 if (code == ENUMERAL_TYPE)
1391 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1392 TYPE_PRECISION (integer_type_node)),
1393 ((TYPE_PRECISION (type)
1394 >= TYPE_PRECISION (integer_type_node))
1395 && TYPE_UNSIGNED (type)));
1397 return convert (type, exp);
1400 /* ??? This should no longer be needed now bit-fields have their
1402 if (TREE_CODE (exp) == COMPONENT_REF
1403 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1404 /* If it's thinner than an int, promote it like a
1405 c_promoting_integer_type_p, otherwise leave it alone. */
1406 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1407 TYPE_PRECISION (integer_type_node)))
1408 return convert (integer_type_node, exp);
1410 if (c_promoting_integer_type_p (type))
1412 /* Preserve unsignedness if not really getting any wider. */
1413 if (TYPE_UNSIGNED (type)
1414 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1415 return convert (unsigned_type_node, exp);
1417 return convert (integer_type_node, exp);
1424 /* Perform default promotions for C data used in expressions.
1425 Enumeral types or short or char are converted to int.
1426 In addition, manifest constants symbols are replaced by their values. */
1429 default_conversion (tree exp)
1432 tree type = TREE_TYPE (exp);
1433 enum tree_code code = TREE_CODE (type);
1435 /* Functions and arrays have been converted during parsing. */
1436 gcc_assert (code != FUNCTION_TYPE);
1437 if (code == ARRAY_TYPE)
1440 /* Constants can be used directly unless they're not loadable. */
1441 if (TREE_CODE (exp) == CONST_DECL)
1442 exp = DECL_INITIAL (exp);
1444 /* Replace a nonvolatile const static variable with its value unless
1445 it is an array, in which case we must be sure that taking the
1446 address of the array produces consistent results. */
1447 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1449 exp = decl_constant_value_for_broken_optimization (exp);
1450 type = TREE_TYPE (exp);
1453 /* Strip no-op conversions. */
1455 STRIP_TYPE_NOPS (exp);
1457 if (TREE_NO_WARNING (orig_exp))
1458 TREE_NO_WARNING (exp) = 1;
1460 if (INTEGRAL_TYPE_P (type))
1461 return perform_integral_promotions (exp);
1463 if (code == VOID_TYPE)
1465 error ("void value not ignored as it ought to be");
1466 return error_mark_node;
1471 /* Look up COMPONENT in a structure or union DECL.
1473 If the component name is not found, returns NULL_TREE. Otherwise,
1474 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1475 stepping down the chain to the component, which is in the last
1476 TREE_VALUE of the list. Normally the list is of length one, but if
1477 the component is embedded within (nested) anonymous structures or
1478 unions, the list steps down the chain to the component. */
1481 lookup_field (tree decl, tree component)
1483 tree type = TREE_TYPE (decl);
1486 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1487 to the field elements. Use a binary search on this array to quickly
1488 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1489 will always be set for structures which have many elements. */
1491 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1494 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1496 field = TYPE_FIELDS (type);
1498 top = TYPE_LANG_SPECIFIC (type)->s->len;
1499 while (top - bot > 1)
1501 half = (top - bot + 1) >> 1;
1502 field = field_array[bot+half];
1504 if (DECL_NAME (field) == NULL_TREE)
1506 /* Step through all anon unions in linear fashion. */
1507 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1509 field = field_array[bot++];
1510 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1511 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1513 tree anon = lookup_field (field, component);
1516 return tree_cons (NULL_TREE, field, anon);
1520 /* Entire record is only anon unions. */
1524 /* Restart the binary search, with new lower bound. */
1528 if (DECL_NAME (field) == component)
1530 if (DECL_NAME (field) < component)
1536 if (DECL_NAME (field_array[bot]) == component)
1537 field = field_array[bot];
1538 else if (DECL_NAME (field) != component)
1543 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1545 if (DECL_NAME (field) == NULL_TREE
1546 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1547 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1549 tree anon = lookup_field (field, component);
1552 return tree_cons (NULL_TREE, field, anon);
1555 if (DECL_NAME (field) == component)
1559 if (field == NULL_TREE)
1563 return tree_cons (NULL_TREE, field, NULL_TREE);
1566 /* Make an expression to refer to the COMPONENT field of
1567 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1570 build_component_ref (tree datum, tree component)
1572 tree type = TREE_TYPE (datum);
1573 enum tree_code code = TREE_CODE (type);
1577 if (!objc_is_public (datum, component))
1578 return error_mark_node;
1580 /* See if there is a field or component with name COMPONENT. */
1582 if (code == RECORD_TYPE || code == UNION_TYPE)
1584 if (!COMPLETE_TYPE_P (type))
1586 c_incomplete_type_error (NULL_TREE, type);
1587 return error_mark_node;
1590 field = lookup_field (datum, component);
1594 error ("%qT has no member named %qE", type, component);
1595 return error_mark_node;
1598 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1599 This might be better solved in future the way the C++ front
1600 end does it - by giving the anonymous entities each a
1601 separate name and type, and then have build_component_ref
1602 recursively call itself. We can't do that here. */
1605 tree subdatum = TREE_VALUE (field);
1607 if (TREE_TYPE (subdatum) == error_mark_node)
1608 return error_mark_node;
1610 ref = build3 (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum,
1612 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1613 TREE_READONLY (ref) = 1;
1614 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1615 TREE_THIS_VOLATILE (ref) = 1;
1617 if (TREE_DEPRECATED (subdatum))
1618 warn_deprecated_use (subdatum);
1622 field = TREE_CHAIN (field);
1628 else if (code != ERROR_MARK)
1629 error ("request for member %qE in something not a structure or union",
1632 return error_mark_node;
1635 /* Given an expression PTR for a pointer, return an expression
1636 for the value pointed to.
1637 ERRORSTRING is the name of the operator to appear in error messages. */
1640 build_indirect_ref (tree ptr, const char *errorstring)
1642 tree pointer = default_conversion (ptr);
1643 tree type = TREE_TYPE (pointer);
1645 if (TREE_CODE (type) == POINTER_TYPE)
1647 if (TREE_CODE (pointer) == ADDR_EXPR
1648 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1649 == TREE_TYPE (type)))
1650 return TREE_OPERAND (pointer, 0);
1653 tree t = TREE_TYPE (type);
1656 ref = build1 (INDIRECT_REF, t, pointer);
1658 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1660 error ("dereferencing pointer to incomplete type");
1661 return error_mark_node;
1663 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1664 warning (0, "dereferencing %<void *%> pointer");
1666 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1667 so that we get the proper error message if the result is used
1668 to assign to. Also, &* is supposed to be a no-op.
1669 And ANSI C seems to specify that the type of the result
1670 should be the const type. */
1671 /* A de-reference of a pointer to const is not a const. It is valid
1672 to change it via some other pointer. */
1673 TREE_READONLY (ref) = TYPE_READONLY (t);
1674 TREE_SIDE_EFFECTS (ref)
1675 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1676 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1680 else if (TREE_CODE (pointer) != ERROR_MARK)
1681 error ("invalid type argument of %qs", errorstring);
1682 return error_mark_node;
1685 /* This handles expressions of the form "a[i]", which denotes
1688 This is logically equivalent in C to *(a+i), but we may do it differently.
1689 If A is a variable or a member, we generate a primitive ARRAY_REF.
1690 This avoids forcing the array out of registers, and can work on
1691 arrays that are not lvalues (for example, members of structures returned
1695 build_array_ref (tree array, tree index)
1697 bool swapped = false;
1698 if (TREE_TYPE (array) == error_mark_node
1699 || TREE_TYPE (index) == error_mark_node)
1700 return error_mark_node;
1702 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1703 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1706 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1707 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1709 error ("subscripted value is neither array nor pointer");
1710 return error_mark_node;
1718 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1720 error ("array subscript is not an integer");
1721 return error_mark_node;
1724 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1726 error ("subscripted value is pointer to function");
1727 return error_mark_node;
1730 /* Subscripting with type char is likely to lose on a machine where
1731 chars are signed. So warn on any machine, but optionally. Don't
1732 warn for unsigned char since that type is safe. Don't warn for
1733 signed char because anyone who uses that must have done so
1734 deliberately. ??? Existing practice has also been to warn only
1735 when the char index is syntactically the index, not for
1738 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1739 warning (OPT_Wchar_subscripts, "array subscript has type %<char%>");
1741 /* Apply default promotions *after* noticing character types. */
1742 index = default_conversion (index);
1744 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1746 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1750 /* An array that is indexed by a non-constant
1751 cannot be stored in a register; we must be able to do
1752 address arithmetic on its address.
1753 Likewise an array of elements of variable size. */
1754 if (TREE_CODE (index) != INTEGER_CST
1755 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1756 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1758 if (!c_mark_addressable (array))
1759 return error_mark_node;
1761 /* An array that is indexed by a constant value which is not within
1762 the array bounds cannot be stored in a register either; because we
1763 would get a crash in store_bit_field/extract_bit_field when trying
1764 to access a non-existent part of the register. */
1765 if (TREE_CODE (index) == INTEGER_CST
1766 && TYPE_DOMAIN (TREE_TYPE (array))
1767 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1769 if (!c_mark_addressable (array))
1770 return error_mark_node;
1776 while (TREE_CODE (foo) == COMPONENT_REF)
1777 foo = TREE_OPERAND (foo, 0);
1778 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1779 pedwarn ("ISO C forbids subscripting %<register%> array");
1780 else if (!flag_isoc99 && !lvalue_p (foo))
1781 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1784 type = TREE_TYPE (TREE_TYPE (array));
1785 if (TREE_CODE (type) != ARRAY_TYPE)
1786 type = TYPE_MAIN_VARIANT (type);
1787 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
1788 /* Array ref is const/volatile if the array elements are
1789 or if the array is. */
1790 TREE_READONLY (rval)
1791 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1792 | TREE_READONLY (array));
1793 TREE_SIDE_EFFECTS (rval)
1794 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1795 | TREE_SIDE_EFFECTS (array));
1796 TREE_THIS_VOLATILE (rval)
1797 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1798 /* This was added by rms on 16 Nov 91.
1799 It fixes vol struct foo *a; a->elts[1]
1800 in an inline function.
1801 Hope it doesn't break something else. */
1802 | TREE_THIS_VOLATILE (array));
1803 return require_complete_type (fold (rval));
1807 tree ar = default_conversion (array);
1809 if (ar == error_mark_node)
1812 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
1813 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
1815 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
1820 /* Build an external reference to identifier ID. FUN indicates
1821 whether this will be used for a function call. LOC is the source
1822 location of the identifier. */
1824 build_external_ref (tree id, int fun, location_t loc)
1827 tree decl = lookup_name (id);
1829 /* In Objective-C, an instance variable (ivar) may be preferred to
1830 whatever lookup_name() found. */
1831 decl = objc_lookup_ivar (decl, id);
1833 if (decl && decl != error_mark_node)
1836 /* Implicit function declaration. */
1837 ref = implicitly_declare (id);
1838 else if (decl == error_mark_node)
1839 /* Don't complain about something that's already been
1840 complained about. */
1841 return error_mark_node;
1844 undeclared_variable (id, loc);
1845 return error_mark_node;
1848 if (TREE_TYPE (ref) == error_mark_node)
1849 return error_mark_node;
1851 if (TREE_DEPRECATED (ref))
1852 warn_deprecated_use (ref);
1854 if (!skip_evaluation)
1855 assemble_external (ref);
1856 TREE_USED (ref) = 1;
1858 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
1860 if (!in_sizeof && !in_typeof)
1861 C_DECL_USED (ref) = 1;
1862 else if (DECL_INITIAL (ref) == 0
1863 && DECL_EXTERNAL (ref)
1864 && !TREE_PUBLIC (ref))
1865 record_maybe_used_decl (ref);
1868 if (TREE_CODE (ref) == CONST_DECL)
1870 ref = DECL_INITIAL (ref);
1871 TREE_CONSTANT (ref) = 1;
1872 TREE_INVARIANT (ref) = 1;
1874 else if (current_function_decl != 0
1875 && !DECL_FILE_SCOPE_P (current_function_decl)
1876 && (TREE_CODE (ref) == VAR_DECL
1877 || TREE_CODE (ref) == PARM_DECL
1878 || TREE_CODE (ref) == FUNCTION_DECL))
1880 tree context = decl_function_context (ref);
1882 if (context != 0 && context != current_function_decl)
1883 DECL_NONLOCAL (ref) = 1;
1889 /* Record details of decls possibly used inside sizeof or typeof. */
1890 struct maybe_used_decl
1894 /* The level seen at (in_sizeof + in_typeof). */
1896 /* The next one at this level or above, or NULL. */
1897 struct maybe_used_decl *next;
1900 static struct maybe_used_decl *maybe_used_decls;
1902 /* Record that DECL, an undefined static function reference seen
1903 inside sizeof or typeof, might be used if the operand of sizeof is
1904 a VLA type or the operand of typeof is a variably modified
1908 record_maybe_used_decl (tree decl)
1910 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
1912 t->level = in_sizeof + in_typeof;
1913 t->next = maybe_used_decls;
1914 maybe_used_decls = t;
1917 /* Pop the stack of decls possibly used inside sizeof or typeof. If
1918 USED is false, just discard them. If it is true, mark them used
1919 (if no longer inside sizeof or typeof) or move them to the next
1920 level up (if still inside sizeof or typeof). */
1923 pop_maybe_used (bool used)
1925 struct maybe_used_decl *p = maybe_used_decls;
1926 int cur_level = in_sizeof + in_typeof;
1927 while (p && p->level > cur_level)
1932 C_DECL_USED (p->decl) = 1;
1934 p->level = cur_level;
1938 if (!used || cur_level == 0)
1939 maybe_used_decls = p;
1942 /* Return the result of sizeof applied to EXPR. */
1945 c_expr_sizeof_expr (struct c_expr expr)
1948 if (expr.value == error_mark_node)
1950 ret.value = error_mark_node;
1951 ret.original_code = ERROR_MARK;
1952 pop_maybe_used (false);
1956 ret.value = c_sizeof (TREE_TYPE (expr.value));
1957 ret.original_code = ERROR_MARK;
1958 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
1963 /* Return the result of sizeof applied to T, a structure for the type
1964 name passed to sizeof (rather than the type itself). */
1967 c_expr_sizeof_type (struct c_type_name *t)
1971 type = groktypename (t);
1972 ret.value = c_sizeof (type);
1973 ret.original_code = ERROR_MARK;
1974 pop_maybe_used (C_TYPE_VARIABLE_SIZE (type));
1978 /* Build a function call to function FUNCTION with parameters PARAMS.
1979 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1980 TREE_VALUE of each node is a parameter-expression.
1981 FUNCTION's data type may be a function type or a pointer-to-function. */
1984 build_function_call (tree function, tree params)
1986 tree fntype, fundecl = 0;
1987 tree coerced_params;
1988 tree name = NULL_TREE, result;
1991 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1992 STRIP_TYPE_NOPS (function);
1994 /* Convert anything with function type to a pointer-to-function. */
1995 if (TREE_CODE (function) == FUNCTION_DECL)
1997 /* Implement type-directed function overloading for builtins.
1998 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
1999 handle all the type checking. The result is a complete expression
2000 that implements this function call. */
2001 tem = resolve_overloaded_builtin (function, params);
2005 name = DECL_NAME (function);
2008 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2009 function = function_to_pointer_conversion (function);
2011 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2012 expressions, like those used for ObjC messenger dispatches. */
2013 function = objc_rewrite_function_call (function, params);
2015 fntype = TREE_TYPE (function);
2017 if (TREE_CODE (fntype) == ERROR_MARK)
2018 return error_mark_node;
2020 if (!(TREE_CODE (fntype) == POINTER_TYPE
2021 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2023 error ("called object %qE is not a function", function);
2024 return error_mark_node;
2027 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2028 current_function_returns_abnormally = 1;
2030 /* fntype now gets the type of function pointed to. */
2031 fntype = TREE_TYPE (fntype);
2033 /* Check that the function is called through a compatible prototype.
2034 If it is not, replace the call by a trap, wrapped up in a compound
2035 expression if necessary. This has the nice side-effect to prevent
2036 the tree-inliner from generating invalid assignment trees which may
2037 blow up in the RTL expander later. */
2038 if (TREE_CODE (function) == NOP_EXPR
2039 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2040 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2041 && !comptypes (fntype, TREE_TYPE (tem)))
2043 tree return_type = TREE_TYPE (fntype);
2044 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2047 /* This situation leads to run-time undefined behavior. We can't,
2048 therefore, simply error unless we can prove that all possible
2049 executions of the program must execute the code. */
2050 warning (0, "function called through a non-compatible type");
2052 /* We can, however, treat "undefined" any way we please.
2053 Call abort to encourage the user to fix the program. */
2054 inform ("if this code is reached, the program will abort");
2056 if (VOID_TYPE_P (return_type))
2062 if (AGGREGATE_TYPE_P (return_type))
2063 rhs = build_compound_literal (return_type,
2064 build_constructor (return_type,
2067 rhs = fold_build1 (NOP_EXPR, return_type, integer_zero_node);
2069 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2073 /* Convert the parameters to the types declared in the
2074 function prototype, or apply default promotions. */
2077 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2079 if (coerced_params == error_mark_node)
2080 return error_mark_node;
2082 /* Check that the arguments to the function are valid. */
2084 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2085 TYPE_ARG_TYPES (fntype));
2087 result = build3 (CALL_EXPR, TREE_TYPE (fntype),
2088 function, coerced_params, NULL_TREE);
2089 TREE_SIDE_EFFECTS (result) = 1;
2091 if (require_constant_value)
2093 result = fold_initializer (result);
2095 if (TREE_CONSTANT (result)
2096 && (name == NULL_TREE
2097 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2098 pedwarn_init ("initializer element is not constant");
2101 result = fold (result);
2103 if (VOID_TYPE_P (TREE_TYPE (result)))
2105 return require_complete_type (result);
2108 /* Convert the argument expressions in the list VALUES
2109 to the types in the list TYPELIST. The result is a list of converted
2110 argument expressions, unless there are too few arguments in which
2111 case it is error_mark_node.
2113 If TYPELIST is exhausted, or when an element has NULL as its type,
2114 perform the default conversions.
2116 PARMLIST is the chain of parm decls for the function being called.
2117 It may be 0, if that info is not available.
2118 It is used only for generating error messages.
2120 FUNCTION is a tree for the called function. It is used only for
2121 error messages, where it is formatted with %qE.
2123 This is also where warnings about wrong number of args are generated.
2125 Both VALUES and the returned value are chains of TREE_LIST nodes
2126 with the elements of the list in the TREE_VALUE slots of those nodes. */
2129 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2131 tree typetail, valtail;
2136 /* Change pointer to function to the function itself for
2138 if (TREE_CODE (function) == ADDR_EXPR
2139 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2140 function = TREE_OPERAND (function, 0);
2142 /* Handle an ObjC selector specially for diagnostics. */
2143 selector = objc_message_selector ();
2145 /* Scan the given expressions and types, producing individual
2146 converted arguments and pushing them on RESULT in reverse order. */
2148 for (valtail = values, typetail = typelist, parmnum = 0;
2150 valtail = TREE_CHAIN (valtail), parmnum++)
2152 tree type = typetail ? TREE_VALUE (typetail) : 0;
2153 tree val = TREE_VALUE (valtail);
2154 tree rname = function;
2155 int argnum = parmnum + 1;
2156 const char *invalid_func_diag;
2158 if (type == void_type_node)
2160 error ("too many arguments to function %qE", function);
2164 if (selector && argnum > 2)
2170 STRIP_TYPE_NOPS (val);
2172 val = require_complete_type (val);
2176 /* Formal parm type is specified by a function prototype. */
2179 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2181 error ("type of formal parameter %d is incomplete", parmnum + 1);
2186 /* Optionally warn about conversions that
2187 differ from the default conversions. */
2188 if (warn_conversion || warn_traditional)
2190 unsigned int formal_prec = TYPE_PRECISION (type);
2192 if (INTEGRAL_TYPE_P (type)
2193 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2194 warning (0, "passing argument %d of %qE as integer "
2195 "rather than floating due to prototype",
2197 if (INTEGRAL_TYPE_P (type)
2198 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2199 warning (0, "passing argument %d of %qE as integer "
2200 "rather than complex due to prototype",
2202 else if (TREE_CODE (type) == COMPLEX_TYPE
2203 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2204 warning (0, "passing argument %d of %qE as complex "
2205 "rather than floating due to prototype",
2207 else if (TREE_CODE (type) == REAL_TYPE
2208 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2209 warning (0, "passing argument %d of %qE as floating "
2210 "rather than integer due to prototype",
2212 else if (TREE_CODE (type) == COMPLEX_TYPE
2213 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2214 warning (0, "passing argument %d of %qE as complex "
2215 "rather than integer due to prototype",
2217 else if (TREE_CODE (type) == REAL_TYPE
2218 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2219 warning (0, "passing argument %d of %qE as floating "
2220 "rather than complex due to prototype",
2222 /* ??? At some point, messages should be written about
2223 conversions between complex types, but that's too messy
2225 else if (TREE_CODE (type) == REAL_TYPE
2226 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2228 /* Warn if any argument is passed as `float',
2229 since without a prototype it would be `double'. */
2230 if (formal_prec == TYPE_PRECISION (float_type_node))
2231 warning (0, "passing argument %d of %qE as %<float%> "
2232 "rather than %<double%> due to prototype",
2235 /* Detect integer changing in width or signedness.
2236 These warnings are only activated with
2237 -Wconversion, not with -Wtraditional. */
2238 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2239 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2241 tree would_have_been = default_conversion (val);
2242 tree type1 = TREE_TYPE (would_have_been);
2244 if (TREE_CODE (type) == ENUMERAL_TYPE
2245 && (TYPE_MAIN_VARIANT (type)
2246 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2247 /* No warning if function asks for enum
2248 and the actual arg is that enum type. */
2250 else if (formal_prec != TYPE_PRECISION (type1))
2251 warning (OPT_Wconversion, "passing argument %d of %qE "
2252 "with different width due to prototype",
2254 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2256 /* Don't complain if the formal parameter type
2257 is an enum, because we can't tell now whether
2258 the value was an enum--even the same enum. */
2259 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2261 else if (TREE_CODE (val) == INTEGER_CST
2262 && int_fits_type_p (val, type))
2263 /* Change in signedness doesn't matter
2264 if a constant value is unaffected. */
2266 /* If the value is extended from a narrower
2267 unsigned type, it doesn't matter whether we
2268 pass it as signed or unsigned; the value
2269 certainly is the same either way. */
2270 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2271 && TYPE_UNSIGNED (TREE_TYPE (val)))
2273 else if (TYPE_UNSIGNED (type))
2274 warning (OPT_Wconversion, "passing argument %d of %qE "
2275 "as unsigned due to prototype",
2278 warning (OPT_Wconversion, "passing argument %d of %qE "
2279 "as signed due to prototype", argnum, rname);
2283 parmval = convert_for_assignment (type, val, ic_argpass,
2287 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2288 && INTEGRAL_TYPE_P (type)
2289 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2290 parmval = default_conversion (parmval);
2292 result = tree_cons (NULL_TREE, parmval, result);
2294 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2295 && (TYPE_PRECISION (TREE_TYPE (val))
2296 < TYPE_PRECISION (double_type_node)))
2297 /* Convert `float' to `double'. */
2298 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2299 else if ((invalid_func_diag =
2300 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2302 error (invalid_func_diag);
2303 return error_mark_node;
2306 /* Convert `short' and `char' to full-size `int'. */
2307 result = tree_cons (NULL_TREE, default_conversion (val), result);
2310 typetail = TREE_CHAIN (typetail);
2313 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2315 error ("too few arguments to function %qE", function);
2316 return error_mark_node;
2319 return nreverse (result);
2322 /* This is the entry point used by the parser to build unary operators
2323 in the input. CODE, a tree_code, specifies the unary operator, and
2324 ARG is the operand. For unary plus, the C parser currently uses
2325 CONVERT_EXPR for code. */
2328 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2330 struct c_expr result;
2332 result.original_code = ERROR_MARK;
2333 result.value = build_unary_op (code, arg.value, 0);
2334 overflow_warning (result.value);
2338 /* This is the entry point used by the parser to build binary operators
2339 in the input. CODE, a tree_code, specifies the binary operator, and
2340 ARG1 and ARG2 are the operands. In addition to constructing the
2341 expression, we check for operands that were written with other binary
2342 operators in a way that is likely to confuse the user. */
2345 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2348 struct c_expr result;
2350 enum tree_code code1 = arg1.original_code;
2351 enum tree_code code2 = arg2.original_code;
2353 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2354 result.original_code = code;
2356 if (TREE_CODE (result.value) == ERROR_MARK)
2359 /* Check for cases such as x+y<<z which users are likely
2361 if (warn_parentheses)
2363 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2365 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2366 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2367 warning (0, "suggest parentheses around + or - inside shift");
2370 if (code == TRUTH_ORIF_EXPR)
2372 if (code1 == TRUTH_ANDIF_EXPR
2373 || code2 == TRUTH_ANDIF_EXPR)
2374 warning (0, "suggest parentheses around && within ||");
2377 if (code == BIT_IOR_EXPR)
2379 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2380 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2381 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2382 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2383 warning (0, "suggest parentheses around arithmetic in operand of |");
2384 /* Check cases like x|y==z */
2385 if (TREE_CODE_CLASS (code1) == tcc_comparison
2386 || TREE_CODE_CLASS (code2) == tcc_comparison)
2387 warning (0, "suggest parentheses around comparison in operand of |");
2390 if (code == BIT_XOR_EXPR)
2392 if (code1 == BIT_AND_EXPR
2393 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2394 || code2 == BIT_AND_EXPR
2395 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2396 warning (0, "suggest parentheses around arithmetic in operand of ^");
2397 /* Check cases like x^y==z */
2398 if (TREE_CODE_CLASS (code1) == tcc_comparison
2399 || TREE_CODE_CLASS (code2) == tcc_comparison)
2400 warning (0, "suggest parentheses around comparison in operand of ^");
2403 if (code == BIT_AND_EXPR)
2405 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2406 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2407 warning (0, "suggest parentheses around + or - in operand of &");
2408 /* Check cases like x&y==z */
2409 if (TREE_CODE_CLASS (code1) == tcc_comparison
2410 || TREE_CODE_CLASS (code2) == tcc_comparison)
2411 warning (0, "suggest parentheses around comparison in operand of &");
2413 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2414 if (TREE_CODE_CLASS (code) == tcc_comparison
2415 && (TREE_CODE_CLASS (code1) == tcc_comparison
2416 || TREE_CODE_CLASS (code2) == tcc_comparison))
2417 warning (0, "comparisons like X<=Y<=Z do not have their mathematical meaning");
2421 unsigned_conversion_warning (result.value, arg1.value);
2422 unsigned_conversion_warning (result.value, arg2.value);
2423 overflow_warning (result.value);
2428 /* Return a tree for the difference of pointers OP0 and OP1.
2429 The resulting tree has type int. */
2432 pointer_diff (tree op0, tree op1)
2434 tree restype = ptrdiff_type_node;
2436 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2437 tree con0, con1, lit0, lit1;
2438 tree orig_op1 = op1;
2440 if (pedantic || warn_pointer_arith)
2442 if (TREE_CODE (target_type) == VOID_TYPE)
2443 pedwarn ("pointer of type %<void *%> used in subtraction");
2444 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2445 pedwarn ("pointer to a function used in subtraction");
2448 /* If the conversion to ptrdiff_type does anything like widening or
2449 converting a partial to an integral mode, we get a convert_expression
2450 that is in the way to do any simplifications.
2451 (fold-const.c doesn't know that the extra bits won't be needed.
2452 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2453 different mode in place.)
2454 So first try to find a common term here 'by hand'; we want to cover
2455 at least the cases that occur in legal static initializers. */
2456 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2457 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2459 if (TREE_CODE (con0) == PLUS_EXPR)
2461 lit0 = TREE_OPERAND (con0, 1);
2462 con0 = TREE_OPERAND (con0, 0);
2465 lit0 = integer_zero_node;
2467 if (TREE_CODE (con1) == PLUS_EXPR)
2469 lit1 = TREE_OPERAND (con1, 1);
2470 con1 = TREE_OPERAND (con1, 0);
2473 lit1 = integer_zero_node;
2475 if (operand_equal_p (con0, con1, 0))
2482 /* First do the subtraction as integers;
2483 then drop through to build the divide operator.
2484 Do not do default conversions on the minus operator
2485 in case restype is a short type. */
2487 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2488 convert (restype, op1), 0);
2489 /* This generates an error if op1 is pointer to incomplete type. */
2490 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2491 error ("arithmetic on pointer to an incomplete type");
2493 /* This generates an error if op0 is pointer to incomplete type. */
2494 op1 = c_size_in_bytes (target_type);
2496 /* Divide by the size, in easiest possible way. */
2497 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2500 /* Construct and perhaps optimize a tree representation
2501 for a unary operation. CODE, a tree_code, specifies the operation
2502 and XARG is the operand.
2503 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2504 the default promotions (such as from short to int).
2505 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2506 allows non-lvalues; this is only used to handle conversion of non-lvalue
2507 arrays to pointers in C99. */
2510 build_unary_op (enum tree_code code, tree xarg, int flag)
2512 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2515 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2517 int noconvert = flag;
2518 const char *invalid_op_diag;
2520 if (typecode == ERROR_MARK)
2521 return error_mark_node;
2522 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2523 typecode = INTEGER_TYPE;
2525 if ((invalid_op_diag
2526 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2528 error (invalid_op_diag);
2529 return error_mark_node;
2535 /* This is used for unary plus, because a CONVERT_EXPR
2536 is enough to prevent anybody from looking inside for
2537 associativity, but won't generate any code. */
2538 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2539 || typecode == COMPLEX_TYPE
2540 || typecode == VECTOR_TYPE))
2542 error ("wrong type argument to unary plus");
2543 return error_mark_node;
2545 else if (!noconvert)
2546 arg = default_conversion (arg);
2547 arg = non_lvalue (arg);
2551 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2552 || typecode == COMPLEX_TYPE
2553 || typecode == VECTOR_TYPE))
2555 error ("wrong type argument to unary minus");
2556 return error_mark_node;
2558 else if (!noconvert)
2559 arg = default_conversion (arg);
2563 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2566 arg = default_conversion (arg);
2568 else if (typecode == COMPLEX_TYPE)
2572 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2574 arg = default_conversion (arg);
2578 error ("wrong type argument to bit-complement");
2579 return error_mark_node;
2584 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2586 error ("wrong type argument to abs");
2587 return error_mark_node;
2589 else if (!noconvert)
2590 arg = default_conversion (arg);
2594 /* Conjugating a real value is a no-op, but allow it anyway. */
2595 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2596 || typecode == COMPLEX_TYPE))
2598 error ("wrong type argument to conjugation");
2599 return error_mark_node;
2601 else if (!noconvert)
2602 arg = default_conversion (arg);
2605 case TRUTH_NOT_EXPR:
2606 if (typecode != INTEGER_TYPE
2607 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2608 && typecode != COMPLEX_TYPE)
2610 error ("wrong type argument to unary exclamation mark");
2611 return error_mark_node;
2613 arg = c_objc_common_truthvalue_conversion (arg);
2614 return invert_truthvalue (arg);
2620 if (TREE_CODE (arg) == COMPLEX_CST)
2621 return TREE_REALPART (arg);
2622 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2623 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2628 if (TREE_CODE (arg) == COMPLEX_CST)
2629 return TREE_IMAGPART (arg);
2630 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2631 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2633 return convert (TREE_TYPE (arg), integer_zero_node);
2635 case PREINCREMENT_EXPR:
2636 case POSTINCREMENT_EXPR:
2637 case PREDECREMENT_EXPR:
2638 case POSTDECREMENT_EXPR:
2640 /* Increment or decrement the real part of the value,
2641 and don't change the imaginary part. */
2642 if (typecode == COMPLEX_TYPE)
2647 pedwarn ("ISO C does not support %<++%> and %<--%>"
2648 " on complex types");
2650 arg = stabilize_reference (arg);
2651 real = build_unary_op (REALPART_EXPR, arg, 1);
2652 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2653 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2654 build_unary_op (code, real, 1), imag);
2657 /* Report invalid types. */
2659 if (typecode != POINTER_TYPE
2660 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2662 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2663 error ("wrong type argument to increment");
2665 error ("wrong type argument to decrement");
2667 return error_mark_node;
2672 tree result_type = TREE_TYPE (arg);
2674 arg = get_unwidened (arg, 0);
2675 argtype = TREE_TYPE (arg);
2677 /* Compute the increment. */
2679 if (typecode == POINTER_TYPE)
2681 /* If pointer target is an undefined struct,
2682 we just cannot know how to do the arithmetic. */
2683 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2685 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2686 error ("increment of pointer to unknown structure");
2688 error ("decrement of pointer to unknown structure");
2690 else if ((pedantic || warn_pointer_arith)
2691 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2692 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2694 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2695 pedwarn ("wrong type argument to increment");
2697 pedwarn ("wrong type argument to decrement");
2700 inc = c_size_in_bytes (TREE_TYPE (result_type));
2703 inc = integer_one_node;
2705 inc = convert (argtype, inc);
2707 /* Complain about anything else that is not a true lvalue. */
2708 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2709 || code == POSTINCREMENT_EXPR)
2712 return error_mark_node;
2714 /* Report a read-only lvalue. */
2715 if (TREE_READONLY (arg))
2716 readonly_error (arg,
2717 ((code == PREINCREMENT_EXPR
2718 || code == POSTINCREMENT_EXPR)
2719 ? lv_increment : lv_decrement));
2721 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2722 val = boolean_increment (code, arg);
2724 val = build2 (code, TREE_TYPE (arg), arg, inc);
2725 TREE_SIDE_EFFECTS (val) = 1;
2726 val = convert (result_type, val);
2727 if (TREE_CODE (val) != code)
2728 TREE_NO_WARNING (val) = 1;
2733 /* Note that this operation never does default_conversion. */
2735 /* Let &* cancel out to simplify resulting code. */
2736 if (TREE_CODE (arg) == INDIRECT_REF)
2738 /* Don't let this be an lvalue. */
2739 if (lvalue_p (TREE_OPERAND (arg, 0)))
2740 return non_lvalue (TREE_OPERAND (arg, 0));
2741 return TREE_OPERAND (arg, 0);
2744 /* For &x[y], return x+y */
2745 if (TREE_CODE (arg) == ARRAY_REF)
2747 tree op0 = TREE_OPERAND (arg, 0);
2748 if (!c_mark_addressable (op0))
2749 return error_mark_node;
2750 return build_binary_op (PLUS_EXPR,
2751 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
2752 ? array_to_pointer_conversion (op0)
2754 TREE_OPERAND (arg, 1), 1);
2757 /* Anything not already handled and not a true memory reference
2758 or a non-lvalue array is an error. */
2759 else if (typecode != FUNCTION_TYPE && !flag
2760 && !lvalue_or_else (arg, lv_addressof))
2761 return error_mark_node;
2763 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2764 argtype = TREE_TYPE (arg);
2766 /* If the lvalue is const or volatile, merge that into the type
2767 to which the address will point. Note that you can't get a
2768 restricted pointer by taking the address of something, so we
2769 only have to deal with `const' and `volatile' here. */
2770 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
2771 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2772 argtype = c_build_type_variant (argtype,
2773 TREE_READONLY (arg),
2774 TREE_THIS_VOLATILE (arg));
2776 if (!c_mark_addressable (arg))
2777 return error_mark_node;
2779 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
2780 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
2782 argtype = build_pointer_type (argtype);
2784 /* ??? Cope with user tricks that amount to offsetof. Delete this
2785 when we have proper support for integer constant expressions. */
2786 val = get_base_address (arg);
2787 if (val && TREE_CODE (val) == INDIRECT_REF
2788 && integer_zerop (TREE_OPERAND (val, 0)))
2789 return fold_convert (argtype, fold_offsetof (arg));
2791 val = build1 (ADDR_EXPR, argtype, arg);
2793 if (TREE_CODE (arg) == COMPOUND_LITERAL_EXPR)
2794 TREE_INVARIANT (val) = TREE_CONSTANT (val) = 1;
2803 argtype = TREE_TYPE (arg);
2804 val = build1 (code, argtype, arg);
2805 return require_constant_value ? fold_initializer (val) : fold (val);
2808 /* Return nonzero if REF is an lvalue valid for this language.
2809 Lvalues can be assigned, unless their type has TYPE_READONLY.
2810 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2815 enum tree_code code = TREE_CODE (ref);
2822 return lvalue_p (TREE_OPERAND (ref, 0));
2824 case COMPOUND_LITERAL_EXPR:
2834 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2835 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2838 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2845 /* Give an error for storing in something that is 'const'. */
2848 readonly_error (tree arg, enum lvalue_use use)
2850 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2851 /* Using this macro rather than (for example) arrays of messages
2852 ensures that all the format strings are checked at compile
2854 #define READONLY_MSG(A, I, D) (use == lv_assign \
2856 : (use == lv_increment ? (I) : (D)))
2857 if (TREE_CODE (arg) == COMPONENT_REF)
2859 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2860 readonly_error (TREE_OPERAND (arg, 0), use);
2862 error (READONLY_MSG (G_("assignment of read-only member %qD"),
2863 G_("increment of read-only member %qD"),
2864 G_("decrement of read-only member %qD")),
2865 TREE_OPERAND (arg, 1));
2867 else if (TREE_CODE (arg) == VAR_DECL)
2868 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
2869 G_("increment of read-only variable %qD"),
2870 G_("decrement of read-only variable %qD")),
2873 error (READONLY_MSG (G_("assignment of read-only location"),
2874 G_("increment of read-only location"),
2875 G_("decrement of read-only location")));
2879 /* Return nonzero if REF is an lvalue valid for this language;
2880 otherwise, print an error message and return zero. USE says
2881 how the lvalue is being used and so selects the error message. */
2884 lvalue_or_else (tree ref, enum lvalue_use use)
2886 int win = lvalue_p (ref);
2894 /* Mark EXP saying that we need to be able to take the
2895 address of it; it should not be allocated in a register.
2896 Returns true if successful. */
2899 c_mark_addressable (tree exp)
2904 switch (TREE_CODE (x))
2907 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2910 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2914 /* ... fall through ... */
2920 x = TREE_OPERAND (x, 0);
2923 case COMPOUND_LITERAL_EXPR:
2925 TREE_ADDRESSABLE (x) = 1;
2932 if (C_DECL_REGISTER (x)
2933 && DECL_NONLOCAL (x))
2935 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2938 ("global register variable %qD used in nested function", x);
2941 pedwarn ("register variable %qD used in nested function", x);
2943 else if (C_DECL_REGISTER (x))
2945 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2946 error ("address of global register variable %qD requested", x);
2948 error ("address of register variable %qD requested", x);
2954 TREE_ADDRESSABLE (x) = 1;
2961 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2964 build_conditional_expr (tree ifexp, tree op1, tree op2)
2968 enum tree_code code1;
2969 enum tree_code code2;
2970 tree result_type = NULL;
2971 tree orig_op1 = op1, orig_op2 = op2;
2973 /* Promote both alternatives. */
2975 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2976 op1 = default_conversion (op1);
2977 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2978 op2 = default_conversion (op2);
2980 if (TREE_CODE (ifexp) == ERROR_MARK
2981 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2982 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2983 return error_mark_node;
2985 type1 = TREE_TYPE (op1);
2986 code1 = TREE_CODE (type1);
2987 type2 = TREE_TYPE (op2);
2988 code2 = TREE_CODE (type2);
2990 /* C90 does not permit non-lvalue arrays in conditional expressions.
2991 In C99 they will be pointers by now. */
2992 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2994 error ("non-lvalue array in conditional expression");
2995 return error_mark_node;
2998 /* Quickly detect the usual case where op1 and op2 have the same type
3000 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3003 result_type = type1;
3005 result_type = TYPE_MAIN_VARIANT (type1);
3007 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3008 || code1 == COMPLEX_TYPE)
3009 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3010 || code2 == COMPLEX_TYPE))
3012 result_type = c_common_type (type1, type2);
3014 /* If -Wsign-compare, warn here if type1 and type2 have
3015 different signedness. We'll promote the signed to unsigned
3016 and later code won't know it used to be different.
3017 Do this check on the original types, so that explicit casts
3018 will be considered, but default promotions won't. */
3019 if (warn_sign_compare && !skip_evaluation)
3021 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3022 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3024 if (unsigned_op1 ^ unsigned_op2)
3026 /* Do not warn if the result type is signed, since the
3027 signed type will only be chosen if it can represent
3028 all the values of the unsigned type. */
3029 if (!TYPE_UNSIGNED (result_type))
3031 /* Do not warn if the signed quantity is an unsuffixed
3032 integer literal (or some static constant expression
3033 involving such literals) and it is non-negative. */
3034 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3035 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3038 warning (0, "signed and unsigned type in conditional expression");
3042 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3044 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3045 pedwarn ("ISO C forbids conditional expr with only one void side");
3046 result_type = void_type_node;
3048 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3050 if (comp_target_types (type1, type2))
3051 result_type = common_pointer_type (type1, type2);
3052 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3053 && TREE_CODE (orig_op1) != NOP_EXPR)
3054 result_type = qualify_type (type2, type1);
3055 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3056 && TREE_CODE (orig_op2) != NOP_EXPR)
3057 result_type = qualify_type (type1, type2);
3058 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3060 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3061 pedwarn ("ISO C forbids conditional expr between "
3062 "%<void *%> and function pointer");
3063 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3064 TREE_TYPE (type2)));
3066 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3068 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3069 pedwarn ("ISO C forbids conditional expr between "
3070 "%<void *%> and function pointer");
3071 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3072 TREE_TYPE (type1)));
3076 pedwarn ("pointer type mismatch in conditional expression");
3077 result_type = build_pointer_type (void_type_node);
3080 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3082 if (!integer_zerop (op2))
3083 pedwarn ("pointer/integer type mismatch in conditional expression");
3086 op2 = null_pointer_node;
3088 result_type = type1;
3090 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3092 if (!integer_zerop (op1))
3093 pedwarn ("pointer/integer type mismatch in conditional expression");
3096 op1 = null_pointer_node;
3098 result_type = type2;
3103 if (flag_cond_mismatch)
3104 result_type = void_type_node;
3107 error ("type mismatch in conditional expression");
3108 return error_mark_node;
3112 /* Merge const and volatile flags of the incoming types. */
3114 = build_type_variant (result_type,
3115 TREE_READONLY (op1) || TREE_READONLY (op2),
3116 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3118 if (result_type != TREE_TYPE (op1))
3119 op1 = convert_and_check (result_type, op1);
3120 if (result_type != TREE_TYPE (op2))
3121 op2 = convert_and_check (result_type, op2);
3123 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3126 /* Return a compound expression that performs two expressions and
3127 returns the value of the second of them. */
3130 build_compound_expr (tree expr1, tree expr2)
3132 if (!TREE_SIDE_EFFECTS (expr1))
3134 /* The left-hand operand of a comma expression is like an expression
3135 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3136 any side-effects, unless it was explicitly cast to (void). */
3137 if (warn_unused_value)
3139 if (VOID_TYPE_P (TREE_TYPE (expr1))
3140 && TREE_CODE (expr1) == CONVERT_EXPR)
3142 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3143 && TREE_CODE (expr1) == COMPOUND_EXPR
3144 && TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR)
3145 ; /* (void) a, (void) b, c */
3147 warning (0, "left-hand operand of comma expression has no effect");
3151 /* With -Wunused, we should also warn if the left-hand operand does have
3152 side-effects, but computes a value which is not used. For example, in
3153 `foo() + bar(), baz()' the result of the `+' operator is not used,
3154 so we should issue a warning. */
3155 else if (warn_unused_value)
3156 warn_if_unused_value (expr1, input_location);
3158 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3161 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3164 build_c_cast (tree type, tree expr)
3168 if (type == error_mark_node || expr == error_mark_node)
3169 return error_mark_node;
3171 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3172 only in <protocol> qualifications. But when constructing cast expressions,
3173 the protocols do matter and must be kept around. */
3174 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3175 return build1 (NOP_EXPR, type, expr);
3177 type = TYPE_MAIN_VARIANT (type);
3179 if (TREE_CODE (type) == ARRAY_TYPE)
3181 error ("cast specifies array type");
3182 return error_mark_node;
3185 if (TREE_CODE (type) == FUNCTION_TYPE)
3187 error ("cast specifies function type");
3188 return error_mark_node;
3191 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3195 if (TREE_CODE (type) == RECORD_TYPE
3196 || TREE_CODE (type) == UNION_TYPE)
3197 pedwarn ("ISO C forbids casting nonscalar to the same type");
3200 else if (TREE_CODE (type) == UNION_TYPE)
3204 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3205 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3206 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3214 pedwarn ("ISO C forbids casts to union type");
3215 t = digest_init (type,
3216 build_constructor (type,
3217 build_tree_list (field, value)),
3219 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3220 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3223 error ("cast to union type from type not present in union");
3224 return error_mark_node;
3230 if (type == void_type_node)
3231 return build1 (CONVERT_EXPR, type, value);
3233 otype = TREE_TYPE (value);
3235 /* Optionally warn about potentially worrisome casts. */
3238 && TREE_CODE (type) == POINTER_TYPE
3239 && TREE_CODE (otype) == POINTER_TYPE)
3241 tree in_type = type;
3242 tree in_otype = otype;
3246 /* Check that the qualifiers on IN_TYPE are a superset of
3247 the qualifiers of IN_OTYPE. The outermost level of
3248 POINTER_TYPE nodes is uninteresting and we stop as soon
3249 as we hit a non-POINTER_TYPE node on either type. */
3252 in_otype = TREE_TYPE (in_otype);
3253 in_type = TREE_TYPE (in_type);
3255 /* GNU C allows cv-qualified function types. 'const'
3256 means the function is very pure, 'volatile' means it
3257 can't return. We need to warn when such qualifiers
3258 are added, not when they're taken away. */
3259 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3260 && TREE_CODE (in_type) == FUNCTION_TYPE)
3261 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3263 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3265 while (TREE_CODE (in_type) == POINTER_TYPE
3266 && TREE_CODE (in_otype) == POINTER_TYPE);
3269 warning (0, "cast adds new qualifiers to function type");
3272 /* There are qualifiers present in IN_OTYPE that are not
3273 present in IN_TYPE. */
3274 warning (0, "cast discards qualifiers from pointer target type");
3277 /* Warn about possible alignment problems. */
3278 if (STRICT_ALIGNMENT
3279 && TREE_CODE (type) == POINTER_TYPE
3280 && TREE_CODE (otype) == POINTER_TYPE
3281 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3282 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3283 /* Don't warn about opaque types, where the actual alignment
3284 restriction is unknown. */
3285 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3286 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3287 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3288 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3289 warning (OPT_Wcast_align,
3290 "cast increases required alignment of target type");
3292 if (TREE_CODE (type) == INTEGER_TYPE
3293 && TREE_CODE (otype) == POINTER_TYPE
3294 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3295 && !TREE_CONSTANT (value))
3296 warning (OPT_Wpointer_to_int_cast,
3297 "cast from pointer to integer of different size");
3299 if (TREE_CODE (value) == CALL_EXPR
3300 && TREE_CODE (type) != TREE_CODE (otype))
3301 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3302 "to non-matching type %qT", otype, type);
3304 if (TREE_CODE (type) == POINTER_TYPE
3305 && TREE_CODE (otype) == INTEGER_TYPE
3306 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3307 /* Don't warn about converting any constant. */
3308 && !TREE_CONSTANT (value))
3309 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3310 "of different size");
3312 if (flag_strict_aliasing && warn_strict_aliasing
3313 && TREE_CODE (type) == POINTER_TYPE
3314 && TREE_CODE (otype) == POINTER_TYPE
3315 && TREE_CODE (expr) == ADDR_EXPR
3316 && (DECL_P (TREE_OPERAND (expr, 0))
3317 || TREE_CODE (TREE_OPERAND (expr, 0)) == COMPONENT_REF)
3318 && !VOID_TYPE_P (TREE_TYPE (type)))
3320 /* Casting the address of an object to non void pointer. Warn
3321 if the cast breaks type based aliasing. */
3322 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3323 warning (OPT_Wstrict_aliasing, "type-punning to incomplete type "
3324 "might break strict-aliasing rules");
3327 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3328 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3330 if (!alias_sets_conflict_p (set1, set2))
3331 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
3332 "pointer will break strict-aliasing rules");
3333 else if (warn_strict_aliasing > 1
3334 && !alias_sets_might_conflict_p (set1, set2))
3335 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
3336 "pointer might break strict-aliasing rules");
3340 /* If pedantic, warn for conversions between function and object
3341 pointer types, except for converting a null pointer constant
3342 to function pointer type. */
3344 && TREE_CODE (type) == POINTER_TYPE
3345 && TREE_CODE (otype) == POINTER_TYPE
3346 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3347 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3348 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3351 && TREE_CODE (type) == POINTER_TYPE
3352 && TREE_CODE (otype) == POINTER_TYPE
3353 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3354 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3355 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3356 && TREE_CODE (expr) != NOP_EXPR))
3357 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3360 value = convert (type, value);
3362 /* Ignore any integer overflow caused by the cast. */
3363 if (TREE_CODE (value) == INTEGER_CST)
3365 /* If OVALUE had overflow set, then so will VALUE, so it
3366 is safe to overwrite. */
3367 if (CONSTANT_CLASS_P (ovalue))
3369 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3370 /* Similarly, constant_overflow cannot have become cleared. */
3371 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3374 TREE_OVERFLOW (value) = 0;
3378 /* Don't let a cast be an lvalue. */
3380 value = non_lvalue (value);
3385 /* Interpret a cast of expression EXPR to type TYPE. */
3387 c_cast_expr (struct c_type_name *type_name, tree expr)
3390 int saved_wsp = warn_strict_prototypes;
3392 /* This avoids warnings about unprototyped casts on
3393 integers. E.g. "#define SIG_DFL (void(*)())0". */
3394 if (TREE_CODE (expr) == INTEGER_CST)
3395 warn_strict_prototypes = 0;
3396 type = groktypename (type_name);
3397 warn_strict_prototypes = saved_wsp;
3399 return build_c_cast (type, expr);
3403 /* Build an assignment expression of lvalue LHS from value RHS.
3404 MODIFYCODE is the code for a binary operator that we use
3405 to combine the old value of LHS with RHS to get the new value.
3406 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3409 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3413 tree lhstype = TREE_TYPE (lhs);
3414 tree olhstype = lhstype;
3416 /* Types that aren't fully specified cannot be used in assignments. */
3417 lhs = require_complete_type (lhs);
3419 /* Avoid duplicate error messages from operands that had errors. */
3420 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3421 return error_mark_node;
3423 STRIP_TYPE_NOPS (rhs);
3427 /* If a binary op has been requested, combine the old LHS value with the RHS
3428 producing the value we should actually store into the LHS. */
3430 if (modifycode != NOP_EXPR)
3432 lhs = stabilize_reference (lhs);
3433 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3436 if (!lvalue_or_else (lhs, lv_assign))
3437 return error_mark_node;
3439 /* Give an error for storing in something that is 'const'. */
3441 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3442 || ((TREE_CODE (lhstype) == RECORD_TYPE
3443 || TREE_CODE (lhstype) == UNION_TYPE)
3444 && C_TYPE_FIELDS_READONLY (lhstype)))
3445 readonly_error (lhs, lv_assign);
3447 /* If storing into a structure or union member,
3448 it has probably been given type `int'.
3449 Compute the type that would go with
3450 the actual amount of storage the member occupies. */
3452 if (TREE_CODE (lhs) == COMPONENT_REF
3453 && (TREE_CODE (lhstype) == INTEGER_TYPE
3454 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3455 || TREE_CODE (lhstype) == REAL_TYPE
3456 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3457 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3459 /* If storing in a field that is in actuality a short or narrower than one,
3460 we must store in the field in its actual type. */
3462 if (lhstype != TREE_TYPE (lhs))
3464 lhs = copy_node (lhs);
3465 TREE_TYPE (lhs) = lhstype;
3468 /* Convert new value to destination type. */
3470 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3471 NULL_TREE, NULL_TREE, 0);
3472 if (TREE_CODE (newrhs) == ERROR_MARK)
3473 return error_mark_node;
3475 /* Emit ObjC write barrier, if necessary. */
3476 if (c_dialect_objc () && flag_objc_gc)
3478 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3483 /* Scan operands. */
3485 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3486 TREE_SIDE_EFFECTS (result) = 1;
3488 /* If we got the LHS in a different type for storing in,
3489 convert the result back to the nominal type of LHS
3490 so that the value we return always has the same type
3491 as the LHS argument. */
3493 if (olhstype == TREE_TYPE (result))
3495 return convert_for_assignment (olhstype, result, ic_assign,
3496 NULL_TREE, NULL_TREE, 0);
3499 /* Convert value RHS to type TYPE as preparation for an assignment
3500 to an lvalue of type TYPE.
3501 The real work of conversion is done by `convert'.
3502 The purpose of this function is to generate error messages
3503 for assignments that are not allowed in C.
3504 ERRTYPE says whether it is argument passing, assignment,
3505 initialization or return.
3507 FUNCTION is a tree for the function being called.
3508 PARMNUM is the number of the argument, for printing in error messages. */
3511 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3512 tree fundecl, tree function, int parmnum)
3514 enum tree_code codel = TREE_CODE (type);
3516 enum tree_code coder;
3517 tree rname = NULL_TREE;
3518 bool objc_ok = false;
3520 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3523 /* Change pointer to function to the function itself for
3525 if (TREE_CODE (function) == ADDR_EXPR
3526 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3527 function = TREE_OPERAND (function, 0);
3529 /* Handle an ObjC selector specially for diagnostics. */
3530 selector = objc_message_selector ();
3532 if (selector && parmnum > 2)
3539 /* This macro is used to emit diagnostics to ensure that all format
3540 strings are complete sentences, visible to gettext and checked at
3542 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3547 pedwarn (AR, parmnum, rname); \
3549 case ic_argpass_nonproto: \
3550 warning (0, AR, parmnum, rname); \
3562 gcc_unreachable (); \
3566 STRIP_TYPE_NOPS (rhs);
3568 if (optimize && TREE_CODE (rhs) == VAR_DECL
3569 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3570 rhs = decl_constant_value_for_broken_optimization (rhs);
3572 rhstype = TREE_TYPE (rhs);
3573 coder = TREE_CODE (rhstype);
3575 if (coder == ERROR_MARK)
3576 return error_mark_node;
3578 if (c_dialect_objc ())
3601 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3604 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3606 overflow_warning (rhs);
3610 if (coder == VOID_TYPE)
3612 /* Except for passing an argument to an unprototyped function,
3613 this is a constraint violation. When passing an argument to
3614 an unprototyped function, it is compile-time undefined;
3615 making it a constraint in that case was rejected in
3617 error ("void value not ignored as it ought to be");
3618 return error_mark_node;
3620 /* A type converts to a reference to it.
3621 This code doesn't fully support references, it's just for the
3622 special case of va_start and va_copy. */
3623 if (codel == REFERENCE_TYPE
3624 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3626 if (!lvalue_p (rhs))
3628 error ("cannot pass rvalue to reference parameter");
3629 return error_mark_node;
3631 if (!c_mark_addressable (rhs))
3632 return error_mark_node;
3633 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3635 /* We already know that these two types are compatible, but they
3636 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3637 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3638 likely to be va_list, a typedef to __builtin_va_list, which
3639 is different enough that it will cause problems later. */
3640 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3641 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3643 rhs = build1 (NOP_EXPR, type, rhs);
3646 /* Some types can interconvert without explicit casts. */
3647 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3648 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3649 return convert (type, rhs);
3650 /* Arithmetic types all interconvert, and enum is treated like int. */
3651 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3652 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3653 || codel == BOOLEAN_TYPE)
3654 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3655 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3656 || coder == BOOLEAN_TYPE))
3657 return convert_and_check (type, rhs);
3659 /* Conversion to a transparent union from its member types.
3660 This applies only to function arguments. */
3661 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3662 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3665 tree marginal_memb_type = 0;
3667 for (memb_types = TYPE_FIELDS (type); memb_types;
3668 memb_types = TREE_CHAIN (memb_types))
3670 tree memb_type = TREE_TYPE (memb_types);
3672 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3673 TYPE_MAIN_VARIANT (rhstype)))
3676 if (TREE_CODE (memb_type) != POINTER_TYPE)
3679 if (coder == POINTER_TYPE)
3681 tree ttl = TREE_TYPE (memb_type);
3682 tree ttr = TREE_TYPE (rhstype);
3684 /* Any non-function converts to a [const][volatile] void *
3685 and vice versa; otherwise, targets must be the same.
3686 Meanwhile, the lhs target must have all the qualifiers of
3688 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3689 || comp_target_types (memb_type, rhstype))
3691 /* If this type won't generate any warnings, use it. */
3692 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3693 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3694 && TREE_CODE (ttl) == FUNCTION_TYPE)
3695 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3696 == TYPE_QUALS (ttr))
3697 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3698 == TYPE_QUALS (ttl))))
3701 /* Keep looking for a better type, but remember this one. */
3702 if (!marginal_memb_type)
3703 marginal_memb_type = memb_type;
3707 /* Can convert integer zero to any pointer type. */
3708 if (integer_zerop (rhs)
3709 || (TREE_CODE (rhs) == NOP_EXPR
3710 && integer_zerop (TREE_OPERAND (rhs, 0))))
3712 rhs = null_pointer_node;
3717 if (memb_types || marginal_memb_type)
3721 /* We have only a marginally acceptable member type;
3722 it needs a warning. */
3723 tree ttl = TREE_TYPE (marginal_memb_type);
3724 tree ttr = TREE_TYPE (rhstype);
3726 /* Const and volatile mean something different for function
3727 types, so the usual warnings are not appropriate. */
3728 if (TREE_CODE (ttr) == FUNCTION_TYPE
3729 && TREE_CODE (ttl) == FUNCTION_TYPE)
3731 /* Because const and volatile on functions are
3732 restrictions that say the function will not do
3733 certain things, it is okay to use a const or volatile
3734 function where an ordinary one is wanted, but not
3736 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3737 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3738 "makes qualified function "
3739 "pointer from unqualified"),
3740 G_("assignment makes qualified "
3741 "function pointer from "
3743 G_("initialization makes qualified "
3744 "function pointer from "
3746 G_("return makes qualified function "
3747 "pointer from unqualified"));
3749 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3750 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3751 "qualifiers from pointer target type"),
3752 G_("assignment discards qualifiers "
3753 "from pointer target type"),
3754 G_("initialization discards qualifiers "
3755 "from pointer target type"),
3756 G_("return discards qualifiers from "
3757 "pointer target type"));
3760 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3761 pedwarn ("ISO C prohibits argument conversion to union type");
3763 return build1 (NOP_EXPR, type, rhs);
3767 /* Conversions among pointers */
3768 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3769 && (coder == codel))
3771 tree ttl = TREE_TYPE (type);
3772 tree ttr = TREE_TYPE (rhstype);
3775 bool is_opaque_pointer;
3776 int target_cmp = 0; /* Cache comp_target_types () result. */
3778 if (TREE_CODE (mvl) != ARRAY_TYPE)
3779 mvl = TYPE_MAIN_VARIANT (mvl);
3780 if (TREE_CODE (mvr) != ARRAY_TYPE)
3781 mvr = TYPE_MAIN_VARIANT (mvr);
3782 /* Opaque pointers are treated like void pointers. */
3783 is_opaque_pointer = (targetm.vector_opaque_p (type)
3784 || targetm.vector_opaque_p (rhstype))
3785 && TREE_CODE (ttl) == VECTOR_TYPE
3786 && TREE_CODE (ttr) == VECTOR_TYPE;
3788 /* C++ does not allow the implicit conversion void* -> T*. However,
3789 for the purpose of reducing the number of false positives, we
3790 tolerate the special case of
3794 where NULL is typically defined in C to be '(void *) 0'. */
3795 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
3796 warning (OPT_Wc___compat, "request for implicit conversion from "
3797 "%qT to %qT not permitted in C++", rhstype, type);
3799 /* Any non-function converts to a [const][volatile] void *
3800 and vice versa; otherwise, targets must be the same.
3801 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3802 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3803 || (target_cmp = comp_target_types (type, rhstype))
3804 || is_opaque_pointer
3805 || (c_common_unsigned_type (mvl)
3806 == c_common_unsigned_type (mvr)))
3809 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3812 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3813 which are not ANSI null ptr constants. */
3814 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3815 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3816 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
3817 "%qE between function pointer "
3819 G_("ISO C forbids assignment between "
3820 "function pointer and %<void *%>"),
3821 G_("ISO C forbids initialization between "
3822 "function pointer and %<void *%>"),
3823 G_("ISO C forbids return between function "
3824 "pointer and %<void *%>"));
3825 /* Const and volatile mean something different for function types,
3826 so the usual warnings are not appropriate. */
3827 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3828 && TREE_CODE (ttl) != FUNCTION_TYPE)
3830 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3832 /* Types differing only by the presence of the 'volatile'
3833 qualifier are acceptable if the 'volatile' has been added
3834 in by the Objective-C EH machinery. */
3835 if (!objc_type_quals_match (ttl, ttr))
3836 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3837 "qualifiers from pointer target type"),
3838 G_("assignment discards qualifiers "
3839 "from pointer target type"),
3840 G_("initialization discards qualifiers "
3841 "from pointer target type"),
3842 G_("return discards qualifiers from "
3843 "pointer target type"));
3845 /* If this is not a case of ignoring a mismatch in signedness,
3847 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3850 /* If there is a mismatch, do warn. */
3851 else if (warn_pointer_sign)
3852 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
3853 "%d of %qE differ in signedness"),
3854 G_("pointer targets in assignment "
3855 "differ in signedness"),
3856 G_("pointer targets in initialization "
3857 "differ in signedness"),
3858 G_("pointer targets in return differ "
3861 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3862 && TREE_CODE (ttr) == FUNCTION_TYPE)
3864 /* Because const and volatile on functions are restrictions
3865 that say the function will not do certain things,
3866 it is okay to use a const or volatile function
3867 where an ordinary one is wanted, but not vice-versa. */
3868 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3869 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3870 "qualified function pointer "
3871 "from unqualified"),
3872 G_("assignment makes qualified function "
3873 "pointer from unqualified"),
3874 G_("initialization makes qualified "
3875 "function pointer from unqualified"),
3876 G_("return makes qualified function "
3877 "pointer from unqualified"));
3881 /* Avoid warning about the volatile ObjC EH puts on decls. */
3883 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
3884 "incompatible pointer type"),
3885 G_("assignment from incompatible pointer type"),
3886 G_("initialization from incompatible "
3888 G_("return from incompatible pointer type"));
3890 return convert (type, rhs);
3892 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3894 /* ??? This should not be an error when inlining calls to
3895 unprototyped functions. */
3896 error ("invalid use of non-lvalue array");
3897 return error_mark_node;
3899 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3901 /* An explicit constant 0 can convert to a pointer,
3902 or one that results from arithmetic, even including
3903 a cast to integer type. */
3904 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3906 !(TREE_CODE (rhs) == NOP_EXPR
3907 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3908 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3909 && integer_zerop (TREE_OPERAND (rhs, 0))))
3910 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3911 "pointer from integer without a cast"),
3912 G_("assignment makes pointer from integer "
3914 G_("initialization makes pointer from "
3915 "integer without a cast"),
3916 G_("return makes pointer from integer "
3919 return convert (type, rhs);
3921 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3923 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
3924 "from pointer without a cast"),
3925 G_("assignment makes integer from pointer "
3927 G_("initialization makes integer from pointer "
3929 G_("return makes integer from pointer "
3931 return convert (type, rhs);
3933 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3934 return convert (type, rhs);
3939 case ic_argpass_nonproto:
3940 /* ??? This should not be an error when inlining calls to
3941 unprototyped functions. */
3942 error ("incompatible type for argument %d of %qE", parmnum, rname);
3945 error ("incompatible types in assignment");
3948 error ("incompatible types in initialization");
3951 error ("incompatible types in return");
3957 return error_mark_node;
3960 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3961 is used for error and waring reporting and indicates which argument
3962 is being processed. */
3965 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3969 /* If FN was prototyped, the value has been converted already
3970 in convert_arguments. */
3971 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3974 type = TREE_TYPE (parm);
3975 ret = convert_for_assignment (type, value,
3976 ic_argpass_nonproto, fn,
3978 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3979 && INTEGRAL_TYPE_P (type)
3980 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3981 ret = default_conversion (ret);
3985 /* If VALUE is a compound expr all of whose expressions are constant, then
3986 return its value. Otherwise, return error_mark_node.
3988 This is for handling COMPOUND_EXPRs as initializer elements
3989 which is allowed with a warning when -pedantic is specified. */
3992 valid_compound_expr_initializer (tree value, tree endtype)
3994 if (TREE_CODE (value) == COMPOUND_EXPR)
3996 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3998 return error_mark_node;
3999 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4002 else if (!initializer_constant_valid_p (value, endtype))
4003 return error_mark_node;
4008 /* Perform appropriate conversions on the initial value of a variable,
4009 store it in the declaration DECL,
4010 and print any error messages that are appropriate.
4011 If the init is invalid, store an ERROR_MARK. */
4014 store_init_value (tree decl, tree init)
4018 /* If variable's type was invalidly declared, just ignore it. */
4020 type = TREE_TYPE (decl);
4021 if (TREE_CODE (type) == ERROR_MARK)
4024 /* Digest the specified initializer into an expression. */
4026 value = digest_init (type, init, true, TREE_STATIC (decl));
4028 /* Store the expression if valid; else report error. */
4030 if (!in_system_header
4031 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4032 warning (OPT_Wtraditional, "traditional C rejects automatic "
4033 "aggregate initialization");
4035 DECL_INITIAL (decl) = value;
4037 /* ANSI wants warnings about out-of-range constant initializers. */
4038 STRIP_TYPE_NOPS (value);
4039 constant_expression_warning (value);
4041 /* Check if we need to set array size from compound literal size. */
4042 if (TREE_CODE (type) == ARRAY_TYPE
4043 && TYPE_DOMAIN (type) == 0
4044 && value != error_mark_node)
4046 tree inside_init = init;
4048 STRIP_TYPE_NOPS (inside_init);
4049 inside_init = fold (inside_init);
4051 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4053 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4055 if (TYPE_DOMAIN (TREE_TYPE (decl)))
4057 /* For int foo[] = (int [3]){1}; we need to set array size
4058 now since later on array initializer will be just the
4059 brace enclosed list of the compound literal. */
4060 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
4062 layout_decl (decl, 0);
4068 /* Methods for storing and printing names for error messages. */
4070 /* Implement a spelling stack that allows components of a name to be pushed
4071 and popped. Each element on the stack is this structure. */
4083 #define SPELLING_STRING 1
4084 #define SPELLING_MEMBER 2
4085 #define SPELLING_BOUNDS 3
4087 static struct spelling *spelling; /* Next stack element (unused). */
4088 static struct spelling *spelling_base; /* Spelling stack base. */
4089 static int spelling_size; /* Size of the spelling stack. */
4091 /* Macros to save and restore the spelling stack around push_... functions.
4092 Alternative to SAVE_SPELLING_STACK. */
4094 #define SPELLING_DEPTH() (spelling - spelling_base)
4095 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4097 /* Push an element on the spelling stack with type KIND and assign VALUE
4100 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4102 int depth = SPELLING_DEPTH (); \
4104 if (depth >= spelling_size) \
4106 spelling_size += 10; \
4107 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4109 RESTORE_SPELLING_DEPTH (depth); \
4112 spelling->kind = (KIND); \
4113 spelling->MEMBER = (VALUE); \
4117 /* Push STRING on the stack. Printed literally. */
4120 push_string (const char *string)
4122 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4125 /* Push a member name on the stack. Printed as '.' STRING. */
4128 push_member_name (tree decl)
4130 const char *const string
4131 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4132 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4135 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4138 push_array_bounds (int bounds)
4140 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4143 /* Compute the maximum size in bytes of the printed spelling. */
4146 spelling_length (void)
4151 for (p = spelling_base; p < spelling; p++)
4153 if (p->kind == SPELLING_BOUNDS)
4156 size += strlen (p->u.s) + 1;
4162 /* Print the spelling to BUFFER and return it. */
4165 print_spelling (char *buffer)
4170 for (p = spelling_base; p < spelling; p++)
4171 if (p->kind == SPELLING_BOUNDS)
4173 sprintf (d, "[%d]", p->u.i);
4179 if (p->kind == SPELLING_MEMBER)
4181 for (s = p->u.s; (*d = *s++); d++)
4188 /* Issue an error message for a bad initializer component.
4189 MSGID identifies the message.
4190 The component name is taken from the spelling stack. */
4193 error_init (const char *msgid)
4197 error ("%s", _(msgid));
4198 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4200 error ("(near initialization for %qs)", ofwhat);
4203 /* Issue a pedantic warning for a bad initializer component.
4204 MSGID identifies the message.
4205 The component name is taken from the spelling stack. */
4208 pedwarn_init (const char *msgid)
4212 pedwarn ("%s", _(msgid));
4213 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4215 pedwarn ("(near initialization for %qs)", ofwhat);
4218 /* Issue a warning for a bad initializer component.
4219 MSGID identifies the message.
4220 The component name is taken from the spelling stack. */
4223 warning_init (const char *msgid)
4227 warning (0, "%s", _(msgid));
4228 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4230 warning (0, "(near initialization for %qs)", ofwhat);
4233 /* If TYPE is an array type and EXPR is a parenthesized string
4234 constant, warn if pedantic that EXPR is being used to initialize an
4235 object of type TYPE. */
4238 maybe_warn_string_init (tree type, struct c_expr expr)
4241 && TREE_CODE (type) == ARRAY_TYPE
4242 && TREE_CODE (expr.value) == STRING_CST
4243 && expr.original_code != STRING_CST)
4244 pedwarn_init ("array initialized from parenthesized string constant");
4247 /* Digest the parser output INIT as an initializer for type TYPE.
4248 Return a C expression of type TYPE to represent the initial value.
4250 If INIT is a string constant, STRICT_STRING is true if it is
4251 unparenthesized or we should not warn here for it being parenthesized.
4252 For other types of INIT, STRICT_STRING is not used.
4254 REQUIRE_CONSTANT requests an error if non-constant initializers or
4255 elements are seen. */
4258 digest_init (tree type, tree init, bool strict_string, int require_constant)
4260 enum tree_code code = TREE_CODE (type);
4261 tree inside_init = init;
4263 if (type == error_mark_node
4264 || init == error_mark_node
4265 || TREE_TYPE (init) == error_mark_node)
4266 return error_mark_node;
4268 STRIP_TYPE_NOPS (inside_init);
4270 inside_init = fold (inside_init);
4272 /* Initialization of an array of chars from a string constant
4273 optionally enclosed in braces. */
4275 if (code == ARRAY_TYPE && inside_init
4276 && TREE_CODE (inside_init) == STRING_CST)
4278 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4279 /* Note that an array could be both an array of character type
4280 and an array of wchar_t if wchar_t is signed char or unsigned
4282 bool char_array = (typ1 == char_type_node
4283 || typ1 == signed_char_type_node
4284 || typ1 == unsigned_char_type_node);
4285 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4286 if (char_array || wchar_array)
4290 expr.value = inside_init;
4291 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4292 maybe_warn_string_init (type, expr);
4295 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4298 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4299 TYPE_MAIN_VARIANT (type)))
4302 if (!wchar_array && !char_string)
4304 error_init ("char-array initialized from wide string");
4305 return error_mark_node;
4307 if (char_string && !char_array)
4309 error_init ("wchar_t-array initialized from non-wide string");
4310 return error_mark_node;
4313 TREE_TYPE (inside_init) = type;
4314 if (TYPE_DOMAIN (type) != 0
4315 && TYPE_SIZE (type) != 0
4316 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4317 /* Subtract 1 (or sizeof (wchar_t))
4318 because it's ok to ignore the terminating null char
4319 that is counted in the length of the constant. */
4320 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4321 TREE_STRING_LENGTH (inside_init)
4322 - ((TYPE_PRECISION (typ1)
4323 != TYPE_PRECISION (char_type_node))
4324 ? (TYPE_PRECISION (wchar_type_node)
4327 pedwarn_init ("initializer-string for array of chars is too long");
4331 else if (INTEGRAL_TYPE_P (typ1))
4333 error_init ("array of inappropriate type initialized "
4334 "from string constant");
4335 return error_mark_node;
4339 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4340 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4341 below and handle as a constructor. */
4342 if (code == VECTOR_TYPE
4343 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4344 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4345 && TREE_CONSTANT (inside_init))
4347 if (TREE_CODE (inside_init) == VECTOR_CST
4348 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4349 TYPE_MAIN_VARIANT (type)))
4352 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4356 /* Iterate through elements and check if all constructor
4357 elements are *_CSTs. */
4358 for (link = CONSTRUCTOR_ELTS (inside_init);
4360 link = TREE_CHAIN (link))
4361 if (! CONSTANT_CLASS_P (TREE_VALUE (link)))
4365 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4369 /* Any type can be initialized
4370 from an expression of the same type, optionally with braces. */
4372 if (inside_init && TREE_TYPE (inside_init) != 0
4373 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4374 TYPE_MAIN_VARIANT (type))
4375 || (code == ARRAY_TYPE
4376 && comptypes (TREE_TYPE (inside_init), type))
4377 || (code == VECTOR_TYPE
4378 && comptypes (TREE_TYPE (inside_init), type))
4379 || (code == POINTER_TYPE
4380 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4381 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4382 TREE_TYPE (type)))))
4384 if (code == POINTER_TYPE)
4386 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4388 if (TREE_CODE (inside_init) == STRING_CST
4389 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4390 inside_init = array_to_pointer_conversion (inside_init);
4393 error_init ("invalid use of non-lvalue array");
4394 return error_mark_node;
4399 if (code == VECTOR_TYPE)
4400 /* Although the types are compatible, we may require a
4402 inside_init = convert (type, inside_init);
4404 if (require_constant && !flag_isoc99
4405 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4407 /* As an extension, allow initializing objects with static storage
4408 duration with compound literals (which are then treated just as
4409 the brace enclosed list they contain). */
4410 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4411 inside_init = DECL_INITIAL (decl);
4414 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4415 && TREE_CODE (inside_init) != CONSTRUCTOR)
4417 error_init ("array initialized from non-constant array expression");
4418 return error_mark_node;
4421 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4422 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4424 /* Compound expressions can only occur here if -pedantic or
4425 -pedantic-errors is specified. In the later case, we always want
4426 an error. In the former case, we simply want a warning. */
4427 if (require_constant && pedantic
4428 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4431 = valid_compound_expr_initializer (inside_init,
4432 TREE_TYPE (inside_init));
4433 if (inside_init == error_mark_node)
4434 error_init ("initializer element is not constant");
4436 pedwarn_init ("initializer element is not constant");
4437 if (flag_pedantic_errors)
4438 inside_init = error_mark_node;
4440 else if (require_constant
4441 && !initializer_constant_valid_p (inside_init,
4442 TREE_TYPE (inside_init)))
4444 error_init ("initializer element is not constant");
4445 inside_init = error_mark_node;
4451 /* Handle scalar types, including conversions. */
4453 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4454 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4455 || code == VECTOR_TYPE)
4457 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4458 && (TREE_CODE (init) == STRING_CST
4459 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4460 init = array_to_pointer_conversion (init);
4462 = convert_for_assignment (type, init, ic_init,
4463 NULL_TREE, NULL_TREE, 0);
4465 /* Check to see if we have already given an error message. */
4466 if (inside_init == error_mark_node)
4468 else if (require_constant && !TREE_CONSTANT (inside_init))
4470 error_init ("initializer element is not constant");
4471 inside_init = error_mark_node;
4473 else if (require_constant
4474 && !initializer_constant_valid_p (inside_init,
4475 TREE_TYPE (inside_init)))
4477 error_init ("initializer element is not computable at load time");
4478 inside_init = error_mark_node;
4484 /* Come here only for records and arrays. */
4486 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4488 error_init ("variable-sized object may not be initialized");
4489 return error_mark_node;
4492 error_init ("invalid initializer");
4493 return error_mark_node;
4496 /* Handle initializers that use braces. */
4498 /* Type of object we are accumulating a constructor for.
4499 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4500 static tree constructor_type;
4502 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4504 static tree constructor_fields;
4506 /* For an ARRAY_TYPE, this is the specified index
4507 at which to store the next element we get. */
4508 static tree constructor_index;
4510 /* For an ARRAY_TYPE, this is the maximum index. */
4511 static tree constructor_max_index;
4513 /* For a RECORD_TYPE, this is the first field not yet written out. */
4514 static tree constructor_unfilled_fields;
4516 /* For an ARRAY_TYPE, this is the index of the first element
4517 not yet written out. */
4518 static tree constructor_unfilled_index;
4520 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4521 This is so we can generate gaps between fields, when appropriate. */
4522 static tree constructor_bit_index;
4524 /* If we are saving up the elements rather than allocating them,
4525 this is the list of elements so far (in reverse order,
4526 most recent first). */
4527 static tree constructor_elements;
4529 /* 1 if constructor should be incrementally stored into a constructor chain,
4530 0 if all the elements should be kept in AVL tree. */
4531 static int constructor_incremental;
4533 /* 1 if so far this constructor's elements are all compile-time constants. */
4534 static int constructor_constant;
4536 /* 1 if so far this constructor's elements are all valid address constants. */
4537 static int constructor_simple;
4539 /* 1 if this constructor is erroneous so far. */
4540 static int constructor_erroneous;
4542 /* Structure for managing pending initializer elements, organized as an
4547 struct init_node *left, *right;
4548 struct init_node *parent;
4554 /* Tree of pending elements at this constructor level.
4555 These are elements encountered out of order
4556 which belong at places we haven't reached yet in actually
4558 Will never hold tree nodes across GC runs. */
4559 static struct init_node *constructor_pending_elts;
4561 /* The SPELLING_DEPTH of this constructor. */
4562 static int constructor_depth;
4564 /* DECL node for which an initializer is being read.
4565 0 means we are reading a constructor expression
4566 such as (struct foo) {...}. */
4567 static tree constructor_decl;
4569 /* Nonzero if this is an initializer for a top-level decl. */
4570 static int constructor_top_level;
4572 /* Nonzero if there were any member designators in this initializer. */
4573 static int constructor_designated;
4575 /* Nesting depth of designator list. */
4576 static int designator_depth;
4578 /* Nonzero if there were diagnosed errors in this designator list. */
4579 static int designator_errorneous;
4582 /* This stack has a level for each implicit or explicit level of
4583 structuring in the initializer, including the outermost one. It
4584 saves the values of most of the variables above. */
4586 struct constructor_range_stack;
4588 struct constructor_stack
4590 struct constructor_stack *next;
4595 tree unfilled_index;
4596 tree unfilled_fields;
4599 struct init_node *pending_elts;
4602 /* If value nonzero, this value should replace the entire
4603 constructor at this level. */
4604 struct c_expr replacement_value;
4605 struct constructor_range_stack *range_stack;
4615 static struct constructor_stack *constructor_stack;
4617 /* This stack represents designators from some range designator up to
4618 the last designator in the list. */
4620 struct constructor_range_stack
4622 struct constructor_range_stack *next, *prev;
4623 struct constructor_stack *stack;
4630 static struct constructor_range_stack *constructor_range_stack;
4632 /* This stack records separate initializers that are nested.
4633 Nested initializers can't happen in ANSI C, but GNU C allows them
4634 in cases like { ... (struct foo) { ... } ... }. */
4636 struct initializer_stack
4638 struct initializer_stack *next;
4640 struct constructor_stack *constructor_stack;
4641 struct constructor_range_stack *constructor_range_stack;
4643 struct spelling *spelling;
4644 struct spelling *spelling_base;
4647 char require_constant_value;
4648 char require_constant_elements;
4651 static struct initializer_stack *initializer_stack;
4653 /* Prepare to parse and output the initializer for variable DECL. */
4656 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4659 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4661 p->decl = constructor_decl;
4662 p->require_constant_value = require_constant_value;
4663 p->require_constant_elements = require_constant_elements;
4664 p->constructor_stack = constructor_stack;
4665 p->constructor_range_stack = constructor_range_stack;
4666 p->elements = constructor_elements;
4667 p->spelling = spelling;
4668 p->spelling_base = spelling_base;
4669 p->spelling_size = spelling_size;
4670 p->top_level = constructor_top_level;
4671 p->next = initializer_stack;
4672 initializer_stack = p;
4674 constructor_decl = decl;
4675 constructor_designated = 0;
4676 constructor_top_level = top_level;
4678 if (decl != 0 && decl != error_mark_node)
4680 require_constant_value = TREE_STATIC (decl);
4681 require_constant_elements
4682 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4683 /* For a scalar, you can always use any value to initialize,
4684 even within braces. */
4685 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4686 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4687 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4688 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4689 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4693 require_constant_value = 0;
4694 require_constant_elements = 0;
4695 locus = "(anonymous)";
4698 constructor_stack = 0;
4699 constructor_range_stack = 0;
4701 missing_braces_mentioned = 0;
4705 RESTORE_SPELLING_DEPTH (0);
4708 push_string (locus);
4714 struct initializer_stack *p = initializer_stack;
4716 /* Free the whole constructor stack of this initializer. */
4717 while (constructor_stack)
4719 struct constructor_stack *q = constructor_stack;
4720 constructor_stack = q->next;
4724 gcc_assert (!constructor_range_stack);
4726 /* Pop back to the data of the outer initializer (if any). */
4727 free (spelling_base);
4729 constructor_decl = p->decl;
4730 require_constant_value = p->require_constant_value;
4731 require_constant_elements = p->require_constant_elements;
4732 constructor_stack = p->constructor_stack;
4733 constructor_range_stack = p->constructor_range_stack;
4734 constructor_elements = p->elements;
4735 spelling = p->spelling;
4736 spelling_base = p->spelling_base;
4737 spelling_size = p->spelling_size;
4738 constructor_top_level = p->top_level;
4739 initializer_stack = p->next;
4743 /* Call here when we see the initializer is surrounded by braces.
4744 This is instead of a call to push_init_level;
4745 it is matched by a call to pop_init_level.
4747 TYPE is the type to initialize, for a constructor expression.
4748 For an initializer for a decl, TYPE is zero. */
4751 really_start_incremental_init (tree type)
4753 struct constructor_stack *p = XNEW (struct constructor_stack);
4756 type = TREE_TYPE (constructor_decl);
4758 if (targetm.vector_opaque_p (type))
4759 error ("opaque vector types cannot be initialized");
4761 p->type = constructor_type;
4762 p->fields = constructor_fields;
4763 p->index = constructor_index;
4764 p->max_index = constructor_max_index;
4765 p->unfilled_index = constructor_unfilled_index;
4766 p->unfilled_fields = constructor_unfilled_fields;
4767 p->bit_index = constructor_bit_index;
4768 p->elements = constructor_elements;
4769 p->constant = constructor_constant;
4770 p->simple = constructor_simple;
4771 p->erroneous = constructor_erroneous;
4772 p->pending_elts = constructor_pending_elts;
4773 p->depth = constructor_depth;
4774 p->replacement_value.value = 0;
4775 p->replacement_value.original_code = ERROR_MARK;
4779 p->incremental = constructor_incremental;
4780 p->designated = constructor_designated;
4782 constructor_stack = p;
4784 constructor_constant = 1;
4785 constructor_simple = 1;
4786 constructor_depth = SPELLING_DEPTH ();
4787 constructor_elements = 0;
4788 constructor_pending_elts = 0;
4789 constructor_type = type;
4790 constructor_incremental = 1;
4791 constructor_designated = 0;
4792 designator_depth = 0;
4793 designator_errorneous = 0;
4795 if (TREE_CODE (constructor_type) == RECORD_TYPE
4796 || TREE_CODE (constructor_type) == UNION_TYPE)
4798 constructor_fields = TYPE_FIELDS (constructor_type);
4799 /* Skip any nameless bit fields at the beginning. */
4800 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4801 && DECL_NAME (constructor_fields) == 0)
4802 constructor_fields = TREE_CHAIN (constructor_fields);
4804 constructor_unfilled_fields = constructor_fields;
4805 constructor_bit_index = bitsize_zero_node;
4807 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4809 if (TYPE_DOMAIN (constructor_type))
4811 constructor_max_index
4812 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4814 /* Detect non-empty initializations of zero-length arrays. */
4815 if (constructor_max_index == NULL_TREE
4816 && TYPE_SIZE (constructor_type))
4817 constructor_max_index = build_int_cst (NULL_TREE, -1);
4819 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4820 to initialize VLAs will cause a proper error; avoid tree
4821 checking errors as well by setting a safe value. */
4822 if (constructor_max_index
4823 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4824 constructor_max_index = build_int_cst (NULL_TREE, -1);
4827 = convert (bitsizetype,
4828 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4832 constructor_index = bitsize_zero_node;
4833 constructor_max_index = NULL_TREE;
4836 constructor_unfilled_index = constructor_index;
4838 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4840 /* Vectors are like simple fixed-size arrays. */
4841 constructor_max_index =
4842 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4843 constructor_index = convert (bitsizetype, bitsize_zero_node);
4844 constructor_unfilled_index = constructor_index;
4848 /* Handle the case of int x = {5}; */
4849 constructor_fields = constructor_type;
4850 constructor_unfilled_fields = constructor_type;
4854 /* Push down into a subobject, for initialization.
4855 If this is for an explicit set of braces, IMPLICIT is 0.
4856 If it is because the next element belongs at a lower level,
4857 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4860 push_init_level (int implicit)
4862 struct constructor_stack *p;
4863 tree value = NULL_TREE;
4865 /* If we've exhausted any levels that didn't have braces,
4866 pop them now. If implicit == 1, this will have been done in
4867 process_init_element; do not repeat it here because in the case
4868 of excess initializers for an empty aggregate this leads to an
4869 infinite cycle of popping a level and immediately recreating
4873 while (constructor_stack->implicit)
4875 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4876 || TREE_CODE (constructor_type) == UNION_TYPE)
4877 && constructor_fields == 0)
4878 process_init_element (pop_init_level (1));
4879 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4880 && constructor_max_index
4881 && tree_int_cst_lt (constructor_max_index,
4883 process_init_element (pop_init_level (1));
4889 /* Unless this is an explicit brace, we need to preserve previous
4893 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4894 || TREE_CODE (constructor_type) == UNION_TYPE)
4895 && constructor_fields)
4896 value = find_init_member (constructor_fields);
4897 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4898 value = find_init_member (constructor_index);
4901 p = XNEW (struct constructor_stack);
4902 p->type = constructor_type;
4903 p->fields = constructor_fields;
4904 p->index = constructor_index;
4905 p->max_index = constructor_max_index;
4906 p->unfilled_index = constructor_unfilled_index;
4907 p->unfilled_fields = constructor_unfilled_fields;
4908 p->bit_index = constructor_bit_index;
4909 p->elements = constructor_elements;
4910 p->constant = constructor_constant;
4911 p->simple = constructor_simple;
4912 p->erroneous = constructor_erroneous;
4913 p->pending_elts = constructor_pending_elts;
4914 p->depth = constructor_depth;
4915 p->replacement_value.value = 0;
4916 p->replacement_value.original_code = ERROR_MARK;
4917 p->implicit = implicit;
4919 p->incremental = constructor_incremental;
4920 p->designated = constructor_designated;
4921 p->next = constructor_stack;
4923 constructor_stack = p;
4925 constructor_constant = 1;
4926 constructor_simple = 1;
4927 constructor_depth = SPELLING_DEPTH ();
4928 constructor_elements = 0;
4929 constructor_incremental = 1;
4930 constructor_designated = 0;
4931 constructor_pending_elts = 0;
4934 p->range_stack = constructor_range_stack;
4935 constructor_range_stack = 0;
4936 designator_depth = 0;
4937 designator_errorneous = 0;
4940 /* Don't die if an entire brace-pair level is superfluous
4941 in the containing level. */
4942 if (constructor_type == 0)
4944 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4945 || TREE_CODE (constructor_type) == UNION_TYPE)
4947 /* Don't die if there are extra init elts at the end. */
4948 if (constructor_fields == 0)
4949 constructor_type = 0;
4952 constructor_type = TREE_TYPE (constructor_fields);
4953 push_member_name (constructor_fields);
4954 constructor_depth++;
4957 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4959 constructor_type = TREE_TYPE (constructor_type);
4960 push_array_bounds (tree_low_cst (constructor_index, 0));
4961 constructor_depth++;
4964 if (constructor_type == 0)
4966 error_init ("extra brace group at end of initializer");
4967 constructor_fields = 0;
4968 constructor_unfilled_fields = 0;
4972 if (value && TREE_CODE (value) == CONSTRUCTOR)
4974 constructor_constant = TREE_CONSTANT (value);
4975 constructor_simple = TREE_STATIC (value);
4976 constructor_elements = CONSTRUCTOR_ELTS (value);
4977 if (constructor_elements
4978 && (TREE_CODE (constructor_type) == RECORD_TYPE
4979 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4980 set_nonincremental_init ();
4983 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4985 missing_braces_mentioned = 1;
4986 warning_init ("missing braces around initializer");
4989 if (TREE_CODE (constructor_type) == RECORD_TYPE
4990 || TREE_CODE (constructor_type) == UNION_TYPE)
4992 constructor_fields = TYPE_FIELDS (constructor_type);
4993 /* Skip any nameless bit fields at the beginning. */
4994 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4995 && DECL_NAME (constructor_fields) == 0)
4996 constructor_fields = TREE_CHAIN (constructor_fields);
4998 constructor_unfilled_fields = constructor_fields;
4999 constructor_bit_index = bitsize_zero_node;
5001 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5003 /* Vectors are like simple fixed-size arrays. */
5004 constructor_max_index =
5005 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5006 constructor_index = convert (bitsizetype, integer_zero_node);
5007 constructor_unfilled_index = constructor_index;
5009 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5011 if (TYPE_DOMAIN (constructor_type))
5013 constructor_max_index
5014 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5016 /* Detect non-empty initializations of zero-length arrays. */
5017 if (constructor_max_index == NULL_TREE
5018 && TYPE_SIZE (constructor_type))
5019 constructor_max_index = build_int_cst (NULL_TREE, -1);
5021 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5022 to initialize VLAs will cause a proper error; avoid tree
5023 checking errors as well by setting a safe value. */
5024 if (constructor_max_index
5025 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5026 constructor_max_index = build_int_cst (NULL_TREE, -1);
5029 = convert (bitsizetype,
5030 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5033 constructor_index = bitsize_zero_node;
5035 constructor_unfilled_index = constructor_index;
5036 if (value && TREE_CODE (value) == STRING_CST)
5038 /* We need to split the char/wchar array into individual
5039 characters, so that we don't have to special case it
5041 set_nonincremental_init_from_string (value);
5046 if (constructor_type != error_mark_node)
5047 warning_init ("braces around scalar initializer");
5048 constructor_fields = constructor_type;
5049 constructor_unfilled_fields = constructor_type;
5053 /* At the end of an implicit or explicit brace level,
5054 finish up that level of constructor. If a single expression
5055 with redundant braces initialized that level, return the
5056 c_expr structure for that expression. Otherwise, the original_code
5057 element is set to ERROR_MARK.
5058 If we were outputting the elements as they are read, return 0 as the value
5059 from inner levels (process_init_element ignores that),
5060 but return error_mark_node as the value from the outermost level
5061 (that's what we want to put in DECL_INITIAL).
5062 Otherwise, return a CONSTRUCTOR expression as the value. */
5065 pop_init_level (int implicit)
5067 struct constructor_stack *p;
5070 ret.original_code = ERROR_MARK;
5074 /* When we come to an explicit close brace,
5075 pop any inner levels that didn't have explicit braces. */
5076 while (constructor_stack->implicit)
5077 process_init_element (pop_init_level (1));
5079 gcc_assert (!constructor_range_stack);
5082 /* Now output all pending elements. */
5083 constructor_incremental = 1;
5084 output_pending_init_elements (1);
5086 p = constructor_stack;
5088 /* Error for initializing a flexible array member, or a zero-length
5089 array member in an inappropriate context. */
5090 if (constructor_type && constructor_fields
5091 && TREE_CODE (constructor_type) == ARRAY_TYPE
5092 && TYPE_DOMAIN (constructor_type)
5093 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5095 /* Silently discard empty initializations. The parser will
5096 already have pedwarned for empty brackets. */
5097 if (integer_zerop (constructor_unfilled_index))
5098 constructor_type = NULL_TREE;
5101 gcc_assert (!TYPE_SIZE (constructor_type));
5103 if (constructor_depth > 2)
5104 error_init ("initialization of flexible array member in a nested context");
5106 pedwarn_init ("initialization of a flexible array member");
5108 /* We have already issued an error message for the existence
5109 of a flexible array member not at the end of the structure.
5110 Discard the initializer so that we do not die later. */
5111 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5112 constructor_type = NULL_TREE;
5116 /* Warn when some struct elements are implicitly initialized to zero. */
5117 if (warn_missing_field_initializers
5119 && TREE_CODE (constructor_type) == RECORD_TYPE
5120 && constructor_unfilled_fields)
5122 /* Do not warn for flexible array members or zero-length arrays. */
5123 while (constructor_unfilled_fields
5124 && (!DECL_SIZE (constructor_unfilled_fields)
5125 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5126 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5128 /* Do not warn if this level of the initializer uses member
5129 designators; it is likely to be deliberate. */
5130 if (constructor_unfilled_fields && !constructor_designated)
5132 push_member_name (constructor_unfilled_fields);
5133 warning_init ("missing initializer");
5134 RESTORE_SPELLING_DEPTH (constructor_depth);
5138 /* Pad out the end of the structure. */
5139 if (p->replacement_value.value)
5140 /* If this closes a superfluous brace pair,
5141 just pass out the element between them. */
5142 ret = p->replacement_value;
5143 else if (constructor_type == 0)
5145 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5146 && TREE_CODE (constructor_type) != UNION_TYPE
5147 && TREE_CODE (constructor_type) != ARRAY_TYPE
5148 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5150 /* A nonincremental scalar initializer--just return
5151 the element, after verifying there is just one. */
5152 if (constructor_elements == 0)
5154 if (!constructor_erroneous)
5155 error_init ("empty scalar initializer");
5156 ret.value = error_mark_node;
5158 else if (TREE_CHAIN (constructor_elements) != 0)
5160 error_init ("extra elements in scalar initializer");
5161 ret.value = TREE_VALUE (constructor_elements);
5164 ret.value = TREE_VALUE (constructor_elements);
5168 if (constructor_erroneous)
5169 ret.value = error_mark_node;
5172 ret.value = build_constructor (constructor_type,
5173 nreverse (constructor_elements));
5174 if (constructor_constant)
5175 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5176 if (constructor_constant && constructor_simple)
5177 TREE_STATIC (ret.value) = 1;
5181 constructor_type = p->type;
5182 constructor_fields = p->fields;
5183 constructor_index = p->index;
5184 constructor_max_index = p->max_index;
5185 constructor_unfilled_index = p->unfilled_index;
5186 constructor_unfilled_fields = p->unfilled_fields;
5187 constructor_bit_index = p->bit_index;
5188 constructor_elements = p->elements;
5189 constructor_constant = p->constant;
5190 constructor_simple = p->simple;
5191 constructor_erroneous = p->erroneous;
5192 constructor_incremental = p->incremental;
5193 constructor_designated = p->designated;
5194 constructor_pending_elts = p->pending_elts;
5195 constructor_depth = p->depth;
5197 constructor_range_stack = p->range_stack;
5198 RESTORE_SPELLING_DEPTH (constructor_depth);
5200 constructor_stack = p->next;
5205 if (constructor_stack == 0)
5207 ret.value = error_mark_node;
5215 /* Common handling for both array range and field name designators.
5216 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5219 set_designator (int array)
5222 enum tree_code subcode;
5224 /* Don't die if an entire brace-pair level is superfluous
5225 in the containing level. */
5226 if (constructor_type == 0)
5229 /* If there were errors in this designator list already, bail out
5231 if (designator_errorneous)
5234 if (!designator_depth)
5236 gcc_assert (!constructor_range_stack);
5238 /* Designator list starts at the level of closest explicit
5240 while (constructor_stack->implicit)
5241 process_init_element (pop_init_level (1));
5242 constructor_designated = 1;
5246 switch (TREE_CODE (constructor_type))
5250 subtype = TREE_TYPE (constructor_fields);
5251 if (subtype != error_mark_node)
5252 subtype = TYPE_MAIN_VARIANT (subtype);
5255 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5261 subcode = TREE_CODE (subtype);
5262 if (array && subcode != ARRAY_TYPE)
5264 error_init ("array index in non-array initializer");
5267 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5269 error_init ("field name not in record or union initializer");
5273 constructor_designated = 1;
5274 push_init_level (2);
5278 /* If there are range designators in designator list, push a new designator
5279 to constructor_range_stack. RANGE_END is end of such stack range or
5280 NULL_TREE if there is no range designator at this level. */
5283 push_range_stack (tree range_end)
5285 struct constructor_range_stack *p;
5287 p = GGC_NEW (struct constructor_range_stack);
5288 p->prev = constructor_range_stack;
5290 p->fields = constructor_fields;
5291 p->range_start = constructor_index;
5292 p->index = constructor_index;
5293 p->stack = constructor_stack;
5294 p->range_end = range_end;
5295 if (constructor_range_stack)
5296 constructor_range_stack->next = p;
5297 constructor_range_stack = p;
5300 /* Within an array initializer, specify the next index to be initialized.
5301 FIRST is that index. If LAST is nonzero, then initialize a range
5302 of indices, running from FIRST through LAST. */
5305 set_init_index (tree first, tree last)
5307 if (set_designator (1))
5310 designator_errorneous = 1;
5312 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5313 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5315 error_init ("array index in initializer not of integer type");
5319 if (TREE_CODE (first) != INTEGER_CST)
5320 error_init ("nonconstant array index in initializer");
5321 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5322 error_init ("nonconstant array index in initializer");
5323 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5324 error_init ("array index in non-array initializer");
5325 else if (tree_int_cst_sgn (first) == -1)
5326 error_init ("array index in initializer exceeds array bounds");
5327 else if (constructor_max_index
5328 && tree_int_cst_lt (constructor_max_index, first))
5329 error_init ("array index in initializer exceeds array bounds");
5332 constructor_index = convert (bitsizetype, first);
5336 if (tree_int_cst_equal (first, last))
5338 else if (tree_int_cst_lt (last, first))
5340 error_init ("empty index range in initializer");
5345 last = convert (bitsizetype, last);
5346 if (constructor_max_index != 0
5347 && tree_int_cst_lt (constructor_max_index, last))
5349 error_init ("array index range in initializer exceeds array bounds");
5356 designator_errorneous = 0;
5357 if (constructor_range_stack || last)
5358 push_range_stack (last);
5362 /* Within a struct initializer, specify the next field to be initialized. */
5365 set_init_label (tree fieldname)
5369 if (set_designator (0))
5372 designator_errorneous = 1;
5374 if (TREE_CODE (constructor_type) != RECORD_TYPE
5375 && TREE_CODE (constructor_type) != UNION_TYPE)
5377 error_init ("field name not in record or union initializer");
5381 for (tail = TYPE_FIELDS (constructor_type); tail;
5382 tail = TREE_CHAIN (tail))
5384 if (DECL_NAME (tail) == fieldname)
5389 error ("unknown field %qE specified in initializer", fieldname);
5392 constructor_fields = tail;
5394 designator_errorneous = 0;
5395 if (constructor_range_stack)
5396 push_range_stack (NULL_TREE);
5400 /* Add a new initializer to the tree of pending initializers. PURPOSE
5401 identifies the initializer, either array index or field in a structure.
5402 VALUE is the value of that index or field. */
5405 add_pending_init (tree purpose, tree value)
5407 struct init_node *p, **q, *r;
5409 q = &constructor_pending_elts;
5412 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5417 if (tree_int_cst_lt (purpose, p->purpose))
5419 else if (tree_int_cst_lt (p->purpose, purpose))
5423 if (TREE_SIDE_EFFECTS (p->value))
5424 warning_init ("initialized field with side-effects overwritten");
5434 bitpos = bit_position (purpose);
5438 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5440 else if (p->purpose != purpose)
5444 if (TREE_SIDE_EFFECTS (p->value))
5445 warning_init ("initialized field with side-effects overwritten");
5452 r = GGC_NEW (struct init_node);
5453 r->purpose = purpose;
5464 struct init_node *s;
5468 if (p->balance == 0)
5470 else if (p->balance < 0)
5477 p->left->parent = p;
5494 constructor_pending_elts = r;
5499 struct init_node *t = r->right;
5503 r->right->parent = r;
5508 p->left->parent = p;
5511 p->balance = t->balance < 0;
5512 r->balance = -(t->balance > 0);
5527 constructor_pending_elts = t;
5533 /* p->balance == +1; growth of left side balances the node. */
5538 else /* r == p->right */
5540 if (p->balance == 0)
5541 /* Growth propagation from right side. */
5543 else if (p->balance > 0)
5550 p->right->parent = p;
5567 constructor_pending_elts = r;
5569 else /* r->balance == -1 */
5572 struct init_node *t = r->left;
5576 r->left->parent = r;
5581 p->right->parent = p;
5584 r->balance = (t->balance < 0);
5585 p->balance = -(t->balance > 0);
5600 constructor_pending_elts = t;
5606 /* p->balance == -1; growth of right side balances the node. */
5617 /* Build AVL tree from a sorted chain. */
5620 set_nonincremental_init (void)
5624 if (TREE_CODE (constructor_type) != RECORD_TYPE
5625 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5628 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5629 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5630 constructor_elements = 0;
5631 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5633 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5634 /* Skip any nameless bit fields at the beginning. */
5635 while (constructor_unfilled_fields != 0
5636 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5637 && DECL_NAME (constructor_unfilled_fields) == 0)
5638 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5641 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5643 if (TYPE_DOMAIN (constructor_type))
5644 constructor_unfilled_index
5645 = convert (bitsizetype,
5646 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5648 constructor_unfilled_index = bitsize_zero_node;
5650 constructor_incremental = 0;
5653 /* Build AVL tree from a string constant. */
5656 set_nonincremental_init_from_string (tree str)
5658 tree value, purpose, type;
5659 HOST_WIDE_INT val[2];
5660 const char *p, *end;
5661 int byte, wchar_bytes, charwidth, bitpos;
5663 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5665 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5666 == TYPE_PRECISION (char_type_node))
5670 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5671 == TYPE_PRECISION (wchar_type_node));
5672 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5674 charwidth = TYPE_PRECISION (char_type_node);
5675 type = TREE_TYPE (constructor_type);
5676 p = TREE_STRING_POINTER (str);
5677 end = p + TREE_STRING_LENGTH (str);
5679 for (purpose = bitsize_zero_node;
5680 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5681 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5683 if (wchar_bytes == 1)
5685 val[1] = (unsigned char) *p++;
5692 for (byte = 0; byte < wchar_bytes; byte++)
5694 if (BYTES_BIG_ENDIAN)
5695 bitpos = (wchar_bytes - byte - 1) * charwidth;
5697 bitpos = byte * charwidth;
5698 val[bitpos < HOST_BITS_PER_WIDE_INT]
5699 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5700 << (bitpos % HOST_BITS_PER_WIDE_INT);
5704 if (!TYPE_UNSIGNED (type))
5706 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5707 if (bitpos < HOST_BITS_PER_WIDE_INT)
5709 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5711 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5715 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5720 else if (val[0] & (((HOST_WIDE_INT) 1)
5721 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5722 val[0] |= ((HOST_WIDE_INT) -1)
5723 << (bitpos - HOST_BITS_PER_WIDE_INT);
5726 value = build_int_cst_wide (type, val[1], val[0]);
5727 add_pending_init (purpose, value);
5730 constructor_incremental = 0;
5733 /* Return value of FIELD in pending initializer or zero if the field was
5734 not initialized yet. */
5737 find_init_member (tree field)
5739 struct init_node *p;
5741 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5743 if (constructor_incremental
5744 && tree_int_cst_lt (field, constructor_unfilled_index))
5745 set_nonincremental_init ();
5747 p = constructor_pending_elts;
5750 if (tree_int_cst_lt (field, p->purpose))
5752 else if (tree_int_cst_lt (p->purpose, field))
5758 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5760 tree bitpos = bit_position (field);
5762 if (constructor_incremental
5763 && (!constructor_unfilled_fields
5764 || tree_int_cst_lt (bitpos,
5765 bit_position (constructor_unfilled_fields))))
5766 set_nonincremental_init ();
5768 p = constructor_pending_elts;
5771 if (field == p->purpose)
5773 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5779 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5781 if (constructor_elements
5782 && TREE_PURPOSE (constructor_elements) == field)
5783 return TREE_VALUE (constructor_elements);
5788 /* "Output" the next constructor element.
5789 At top level, really output it to assembler code now.
5790 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5791 TYPE is the data type that the containing data type wants here.
5792 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5793 If VALUE is a string constant, STRICT_STRING is true if it is
5794 unparenthesized or we should not warn here for it being parenthesized.
5795 For other types of VALUE, STRICT_STRING is not used.
5797 PENDING if non-nil means output pending elements that belong
5798 right after this element. (PENDING is normally 1;
5799 it is 0 while outputting pending elements, to avoid recursion.) */
5802 output_init_element (tree value, bool strict_string, tree type, tree field,
5805 if (type == error_mark_node || value == error_mark_node)
5807 constructor_erroneous = 1;
5810 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5811 && (TREE_CODE (value) == STRING_CST
5812 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
5813 && !(TREE_CODE (value) == STRING_CST
5814 && TREE_CODE (type) == ARRAY_TYPE
5815 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5816 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5817 TYPE_MAIN_VARIANT (type)))
5818 value = array_to_pointer_conversion (value);
5820 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5821 && require_constant_value && !flag_isoc99 && pending)
5823 /* As an extension, allow initializing objects with static storage
5824 duration with compound literals (which are then treated just as
5825 the brace enclosed list they contain). */
5826 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5827 value = DECL_INITIAL (decl);
5830 if (value == error_mark_node)
5831 constructor_erroneous = 1;
5832 else if (!TREE_CONSTANT (value))
5833 constructor_constant = 0;
5834 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5835 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5836 || TREE_CODE (constructor_type) == UNION_TYPE)
5837 && DECL_C_BIT_FIELD (field)
5838 && TREE_CODE (value) != INTEGER_CST))
5839 constructor_simple = 0;
5841 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5843 if (require_constant_value)
5845 error_init ("initializer element is not constant");
5846 value = error_mark_node;
5848 else if (require_constant_elements)
5849 pedwarn ("initializer element is not computable at load time");
5852 /* If this field is empty (and not at the end of structure),
5853 don't do anything other than checking the initializer. */
5855 && (TREE_TYPE (field) == error_mark_node
5856 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5857 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5858 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5859 || TREE_CHAIN (field)))))
5862 value = digest_init (type, value, strict_string, require_constant_value);
5863 if (value == error_mark_node)
5865 constructor_erroneous = 1;
5869 /* If this element doesn't come next in sequence,
5870 put it on constructor_pending_elts. */
5871 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5872 && (!constructor_incremental
5873 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5875 if (constructor_incremental
5876 && tree_int_cst_lt (field, constructor_unfilled_index))
5877 set_nonincremental_init ();
5879 add_pending_init (field, value);
5882 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5883 && (!constructor_incremental
5884 || field != constructor_unfilled_fields))
5886 /* We do this for records but not for unions. In a union,
5887 no matter which field is specified, it can be initialized
5888 right away since it starts at the beginning of the union. */
5889 if (constructor_incremental)
5891 if (!constructor_unfilled_fields)
5892 set_nonincremental_init ();
5895 tree bitpos, unfillpos;
5897 bitpos = bit_position (field);
5898 unfillpos = bit_position (constructor_unfilled_fields);
5900 if (tree_int_cst_lt (bitpos, unfillpos))
5901 set_nonincremental_init ();
5905 add_pending_init (field, value);
5908 else if (TREE_CODE (constructor_type) == UNION_TYPE
5909 && constructor_elements)
5911 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5912 warning_init ("initialized field with side-effects overwritten");
5914 /* We can have just one union field set. */
5915 constructor_elements = 0;
5918 /* Otherwise, output this element either to
5919 constructor_elements or to the assembler file. */
5921 if (field && TREE_CODE (field) == INTEGER_CST)
5922 field = copy_node (field);
5923 constructor_elements
5924 = tree_cons (field, value, constructor_elements);
5926 /* Advance the variable that indicates sequential elements output. */
5927 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5928 constructor_unfilled_index
5929 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5931 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5933 constructor_unfilled_fields
5934 = TREE_CHAIN (constructor_unfilled_fields);
5936 /* Skip any nameless bit fields. */
5937 while (constructor_unfilled_fields != 0
5938 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5939 && DECL_NAME (constructor_unfilled_fields) == 0)
5940 constructor_unfilled_fields =
5941 TREE_CHAIN (constructor_unfilled_fields);
5943 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5944 constructor_unfilled_fields = 0;
5946 /* Now output any pending elements which have become next. */
5948 output_pending_init_elements (0);
5951 /* Output any pending elements which have become next.
5952 As we output elements, constructor_unfilled_{fields,index}
5953 advances, which may cause other elements to become next;
5954 if so, they too are output.
5956 If ALL is 0, we return when there are
5957 no more pending elements to output now.
5959 If ALL is 1, we output space as necessary so that
5960 we can output all the pending elements. */
5963 output_pending_init_elements (int all)
5965 struct init_node *elt = constructor_pending_elts;
5970 /* Look through the whole pending tree.
5971 If we find an element that should be output now,
5972 output it. Otherwise, set NEXT to the element
5973 that comes first among those still pending. */
5978 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5980 if (tree_int_cst_equal (elt->purpose,
5981 constructor_unfilled_index))
5982 output_init_element (elt->value, true,
5983 TREE_TYPE (constructor_type),
5984 constructor_unfilled_index, 0);
5985 else if (tree_int_cst_lt (constructor_unfilled_index,
5988 /* Advance to the next smaller node. */
5993 /* We have reached the smallest node bigger than the
5994 current unfilled index. Fill the space first. */
5995 next = elt->purpose;
6001 /* Advance to the next bigger node. */
6006 /* We have reached the biggest node in a subtree. Find
6007 the parent of it, which is the next bigger node. */
6008 while (elt->parent && elt->parent->right == elt)
6011 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6014 next = elt->purpose;
6020 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6021 || TREE_CODE (constructor_type) == UNION_TYPE)
6023 tree ctor_unfilled_bitpos, elt_bitpos;
6025 /* If the current record is complete we are done. */
6026 if (constructor_unfilled_fields == 0)
6029 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6030 elt_bitpos = bit_position (elt->purpose);
6031 /* We can't compare fields here because there might be empty
6032 fields in between. */
6033 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6035 constructor_unfilled_fields = elt->purpose;
6036 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6039 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6041 /* Advance to the next smaller node. */
6046 /* We have reached the smallest node bigger than the
6047 current unfilled field. Fill the space first. */
6048 next = elt->purpose;
6054 /* Advance to the next bigger node. */
6059 /* We have reached the biggest node in a subtree. Find
6060 the parent of it, which is the next bigger node. */
6061 while (elt->parent && elt->parent->right == elt)
6065 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6066 bit_position (elt->purpose))))
6068 next = elt->purpose;
6076 /* Ordinarily return, but not if we want to output all
6077 and there are elements left. */
6078 if (!(all && next != 0))
6081 /* If it's not incremental, just skip over the gap, so that after
6082 jumping to retry we will output the next successive element. */
6083 if (TREE_CODE (constructor_type) == RECORD_TYPE
6084 || TREE_CODE (constructor_type) == UNION_TYPE)
6085 constructor_unfilled_fields = next;
6086 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6087 constructor_unfilled_index = next;
6089 /* ELT now points to the node in the pending tree with the next
6090 initializer to output. */
6094 /* Add one non-braced element to the current constructor level.
6095 This adjusts the current position within the constructor's type.
6096 This may also start or terminate implicit levels
6097 to handle a partly-braced initializer.
6099 Once this has found the correct level for the new element,
6100 it calls output_init_element. */
6103 process_init_element (struct c_expr value)
6105 tree orig_value = value.value;
6106 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6107 bool strict_string = value.original_code == STRING_CST;
6109 designator_depth = 0;
6110 designator_errorneous = 0;
6112 /* Handle superfluous braces around string cst as in
6113 char x[] = {"foo"}; */
6116 && TREE_CODE (constructor_type) == ARRAY_TYPE
6117 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6118 && integer_zerop (constructor_unfilled_index))
6120 if (constructor_stack->replacement_value.value)
6121 error_init ("excess elements in char array initializer");
6122 constructor_stack->replacement_value = value;
6126 if (constructor_stack->replacement_value.value != 0)
6128 error_init ("excess elements in struct initializer");
6132 /* Ignore elements of a brace group if it is entirely superfluous
6133 and has already been diagnosed. */
6134 if (constructor_type == 0)
6137 /* If we've exhausted any levels that didn't have braces,
6139 while (constructor_stack->implicit)
6141 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6142 || TREE_CODE (constructor_type) == UNION_TYPE)
6143 && constructor_fields == 0)
6144 process_init_element (pop_init_level (1));
6145 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6146 && (constructor_max_index == 0
6147 || tree_int_cst_lt (constructor_max_index,
6148 constructor_index)))
6149 process_init_element (pop_init_level (1));
6154 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6155 if (constructor_range_stack)
6157 /* If value is a compound literal and we'll be just using its
6158 content, don't put it into a SAVE_EXPR. */
6159 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6160 || !require_constant_value
6162 value.value = save_expr (value.value);
6167 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6170 enum tree_code fieldcode;
6172 if (constructor_fields == 0)
6174 pedwarn_init ("excess elements in struct initializer");
6178 fieldtype = TREE_TYPE (constructor_fields);
6179 if (fieldtype != error_mark_node)
6180 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6181 fieldcode = TREE_CODE (fieldtype);
6183 /* Error for non-static initialization of a flexible array member. */
6184 if (fieldcode == ARRAY_TYPE
6185 && !require_constant_value
6186 && TYPE_SIZE (fieldtype) == NULL_TREE
6187 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6189 error_init ("non-static initialization of a flexible array member");
6193 /* Accept a string constant to initialize a subarray. */
6194 if (value.value != 0
6195 && fieldcode == ARRAY_TYPE
6196 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6198 value.value = orig_value;
6199 /* Otherwise, if we have come to a subaggregate,
6200 and we don't have an element of its type, push into it. */
6201 else if (value.value != 0
6202 && value.value != error_mark_node
6203 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6204 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6205 || fieldcode == UNION_TYPE))
6207 push_init_level (1);
6213 push_member_name (constructor_fields);
6214 output_init_element (value.value, strict_string,
6215 fieldtype, constructor_fields, 1);
6216 RESTORE_SPELLING_DEPTH (constructor_depth);
6219 /* Do the bookkeeping for an element that was
6220 directly output as a constructor. */
6222 /* For a record, keep track of end position of last field. */
6223 if (DECL_SIZE (constructor_fields))
6224 constructor_bit_index
6225 = size_binop (PLUS_EXPR,
6226 bit_position (constructor_fields),
6227 DECL_SIZE (constructor_fields));
6229 /* If the current field was the first one not yet written out,
6230 it isn't now, so update. */
6231 if (constructor_unfilled_fields == constructor_fields)
6233 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6234 /* Skip any nameless bit fields. */
6235 while (constructor_unfilled_fields != 0
6236 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6237 && DECL_NAME (constructor_unfilled_fields) == 0)
6238 constructor_unfilled_fields =
6239 TREE_CHAIN (constructor_unfilled_fields);
6243 constructor_fields = TREE_CHAIN (constructor_fields);
6244 /* Skip any nameless bit fields at the beginning. */
6245 while (constructor_fields != 0
6246 && DECL_C_BIT_FIELD (constructor_fields)
6247 && DECL_NAME (constructor_fields) == 0)
6248 constructor_fields = TREE_CHAIN (constructor_fields);
6250 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6253 enum tree_code fieldcode;
6255 if (constructor_fields == 0)
6257 pedwarn_init ("excess elements in union initializer");
6261 fieldtype = TREE_TYPE (constructor_fields);
6262 if (fieldtype != error_mark_node)
6263 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6264 fieldcode = TREE_CODE (fieldtype);
6266 /* Warn that traditional C rejects initialization of unions.
6267 We skip the warning if the value is zero. This is done
6268 under the assumption that the zero initializer in user
6269 code appears conditioned on e.g. __STDC__ to avoid
6270 "missing initializer" warnings and relies on default
6271 initialization to zero in the traditional C case.
6272 We also skip the warning if the initializer is designated,
6273 again on the assumption that this must be conditional on
6274 __STDC__ anyway (and we've already complained about the
6275 member-designator already). */
6276 if (!in_system_header && !constructor_designated
6277 && !(value.value && (integer_zerop (value.value)
6278 || real_zerop (value.value))))
6279 warning (OPT_Wtraditional, "traditional C rejects initialization "
6282 /* Accept a string constant to initialize a subarray. */
6283 if (value.value != 0
6284 && fieldcode == ARRAY_TYPE
6285 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6287 value.value = orig_value;
6288 /* Otherwise, if we have come to a subaggregate,
6289 and we don't have an element of its type, push into it. */
6290 else if (value.value != 0
6291 && value.value != error_mark_node
6292 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6293 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6294 || fieldcode == UNION_TYPE))
6296 push_init_level (1);
6302 push_member_name (constructor_fields);
6303 output_init_element (value.value, strict_string,
6304 fieldtype, constructor_fields, 1);
6305 RESTORE_SPELLING_DEPTH (constructor_depth);
6308 /* Do the bookkeeping for an element that was
6309 directly output as a constructor. */
6311 constructor_bit_index = DECL_SIZE (constructor_fields);
6312 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6315 constructor_fields = 0;
6317 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6319 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6320 enum tree_code eltcode = TREE_CODE (elttype);
6322 /* Accept a string constant to initialize a subarray. */
6323 if (value.value != 0
6324 && eltcode == ARRAY_TYPE
6325 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6327 value.value = orig_value;
6328 /* Otherwise, if we have come to a subaggregate,
6329 and we don't have an element of its type, push into it. */
6330 else if (value.value != 0
6331 && value.value != error_mark_node
6332 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6333 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6334 || eltcode == UNION_TYPE))
6336 push_init_level (1);
6340 if (constructor_max_index != 0
6341 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6342 || integer_all_onesp (constructor_max_index)))
6344 pedwarn_init ("excess elements in array initializer");
6348 /* Now output the actual element. */
6351 push_array_bounds (tree_low_cst (constructor_index, 0));
6352 output_init_element (value.value, strict_string,
6353 elttype, constructor_index, 1);
6354 RESTORE_SPELLING_DEPTH (constructor_depth);
6358 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6361 /* If we are doing the bookkeeping for an element that was
6362 directly output as a constructor, we must update
6363 constructor_unfilled_index. */
6364 constructor_unfilled_index = constructor_index;
6366 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6368 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6370 /* Do a basic check of initializer size. Note that vectors
6371 always have a fixed size derived from their type. */
6372 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6374 pedwarn_init ("excess elements in vector initializer");
6378 /* Now output the actual element. */
6380 output_init_element (value.value, strict_string,
6381 elttype, constructor_index, 1);
6384 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6387 /* If we are doing the bookkeeping for an element that was
6388 directly output as a constructor, we must update
6389 constructor_unfilled_index. */
6390 constructor_unfilled_index = constructor_index;
6393 /* Handle the sole element allowed in a braced initializer
6394 for a scalar variable. */
6395 else if (constructor_type != error_mark_node
6396 && constructor_fields == 0)
6398 pedwarn_init ("excess elements in scalar initializer");
6404 output_init_element (value.value, strict_string,
6405 constructor_type, NULL_TREE, 1);
6406 constructor_fields = 0;
6409 /* Handle range initializers either at this level or anywhere higher
6410 in the designator stack. */
6411 if (constructor_range_stack)
6413 struct constructor_range_stack *p, *range_stack;
6416 range_stack = constructor_range_stack;
6417 constructor_range_stack = 0;
6418 while (constructor_stack != range_stack->stack)
6420 gcc_assert (constructor_stack->implicit);
6421 process_init_element (pop_init_level (1));
6423 for (p = range_stack;
6424 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6427 gcc_assert (constructor_stack->implicit);
6428 process_init_element (pop_init_level (1));
6431 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6432 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6437 constructor_index = p->index;
6438 constructor_fields = p->fields;
6439 if (finish && p->range_end && p->index == p->range_start)
6447 push_init_level (2);
6448 p->stack = constructor_stack;
6449 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6450 p->index = p->range_start;
6454 constructor_range_stack = range_stack;
6461 constructor_range_stack = 0;
6464 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6465 (guaranteed to be 'volatile' or null) and ARGS (represented using
6466 an ASM_EXPR node). */
6468 build_asm_stmt (tree cv_qualifier, tree args)
6470 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6471 ASM_VOLATILE_P (args) = 1;
6472 return add_stmt (args);
6475 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6476 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6477 SIMPLE indicates whether there was anything at all after the
6478 string in the asm expression -- asm("blah") and asm("blah" : )
6479 are subtly different. We use a ASM_EXPR node to represent this. */
6481 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6487 const char *constraint;
6488 const char **oconstraints;
6489 bool allows_mem, allows_reg, is_inout;
6490 int ninputs, noutputs;
6492 ninputs = list_length (inputs);
6493 noutputs = list_length (outputs);
6494 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6496 string = resolve_asm_operand_names (string, outputs, inputs);
6498 /* Remove output conversions that change the type but not the mode. */
6499 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6501 tree output = TREE_VALUE (tail);
6503 /* ??? Really, this should not be here. Users should be using a
6504 proper lvalue, dammit. But there's a long history of using casts
6505 in the output operands. In cases like longlong.h, this becomes a
6506 primitive form of typechecking -- if the cast can be removed, then
6507 the output operand had a type of the proper width; otherwise we'll
6508 get an error. Gross, but ... */
6509 STRIP_NOPS (output);
6511 if (!lvalue_or_else (output, lv_asm))
6512 output = error_mark_node;
6514 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6515 oconstraints[i] = constraint;
6517 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6518 &allows_mem, &allows_reg, &is_inout))
6520 /* If the operand is going to end up in memory,
6521 mark it addressable. */
6522 if (!allows_reg && !c_mark_addressable (output))
6523 output = error_mark_node;
6526 output = error_mark_node;
6528 TREE_VALUE (tail) = output;
6531 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6535 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6536 input = TREE_VALUE (tail);
6538 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6539 oconstraints, &allows_mem, &allows_reg))
6541 /* If the operand is going to end up in memory,
6542 mark it addressable. */
6543 if (!allows_reg && allows_mem)
6545 /* Strip the nops as we allow this case. FIXME, this really
6546 should be rejected or made deprecated. */
6548 if (!c_mark_addressable (input))
6549 input = error_mark_node;
6553 input = error_mark_node;
6555 TREE_VALUE (tail) = input;
6558 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6560 /* Simple asm statements are treated as volatile. */
6563 ASM_VOLATILE_P (args) = 1;
6564 ASM_INPUT_P (args) = 1;
6570 /* Generate a goto statement to LABEL. */
6573 c_finish_goto_label (tree label)
6575 tree decl = lookup_label (label);
6579 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6581 error ("jump into statement expression");
6585 if (C_DECL_UNJUMPABLE_VM (decl))
6587 error ("jump into scope of identifier with variably modified type");
6591 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6593 /* No jump from outside this statement expression context, so
6594 record that there is a jump from within this context. */
6595 struct c_label_list *nlist;
6596 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6597 nlist->next = label_context_stack_se->labels_used;
6598 nlist->label = decl;
6599 label_context_stack_se->labels_used = nlist;
6602 if (!C_DECL_UNDEFINABLE_VM (decl))
6604 /* No jump from outside this context context of identifiers with
6605 variably modified type, so record that there is a jump from
6606 within this context. */
6607 struct c_label_list *nlist;
6608 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6609 nlist->next = label_context_stack_vm->labels_used;
6610 nlist->label = decl;
6611 label_context_stack_vm->labels_used = nlist;
6614 TREE_USED (decl) = 1;
6615 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6618 /* Generate a computed goto statement to EXPR. */
6621 c_finish_goto_ptr (tree expr)
6624 pedwarn ("ISO C forbids %<goto *expr;%>");
6625 expr = convert (ptr_type_node, expr);
6626 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6629 /* Generate a C `return' statement. RETVAL is the expression for what
6630 to return, or a null pointer for `return;' with no value. */
6633 c_finish_return (tree retval)
6635 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6637 if (TREE_THIS_VOLATILE (current_function_decl))
6638 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6642 current_function_returns_null = 1;
6643 if ((warn_return_type || flag_isoc99)
6644 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6645 pedwarn_c99 ("%<return%> with no value, in "
6646 "function returning non-void");
6648 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6650 current_function_returns_null = 1;
6651 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6652 pedwarn ("%<return%> with a value, in function returning void");
6656 tree t = convert_for_assignment (valtype, retval, ic_return,
6657 NULL_TREE, NULL_TREE, 0);
6658 tree res = DECL_RESULT (current_function_decl);
6661 current_function_returns_value = 1;
6662 if (t == error_mark_node)
6665 inner = t = convert (TREE_TYPE (res), t);
6667 /* Strip any conversions, additions, and subtractions, and see if
6668 we are returning the address of a local variable. Warn if so. */
6671 switch (TREE_CODE (inner))
6673 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6675 inner = TREE_OPERAND (inner, 0);
6679 /* If the second operand of the MINUS_EXPR has a pointer
6680 type (or is converted from it), this may be valid, so
6681 don't give a warning. */
6683 tree op1 = TREE_OPERAND (inner, 1);
6685 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6686 && (TREE_CODE (op1) == NOP_EXPR
6687 || TREE_CODE (op1) == NON_LVALUE_EXPR
6688 || TREE_CODE (op1) == CONVERT_EXPR))
6689 op1 = TREE_OPERAND (op1, 0);
6691 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6694 inner = TREE_OPERAND (inner, 0);
6699 inner = TREE_OPERAND (inner, 0);
6701 while (REFERENCE_CLASS_P (inner)
6702 && TREE_CODE (inner) != INDIRECT_REF)
6703 inner = TREE_OPERAND (inner, 0);
6706 && !DECL_EXTERNAL (inner)
6707 && !TREE_STATIC (inner)
6708 && DECL_CONTEXT (inner) == current_function_decl)
6709 warning (0, "function returns address of local variable");
6719 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6722 return add_stmt (build_stmt (RETURN_EXPR, retval));
6726 /* The SWITCH_EXPR being built. */
6729 /* The original type of the testing expression, i.e. before the
6730 default conversion is applied. */
6733 /* A splay-tree mapping the low element of a case range to the high
6734 element, or NULL_TREE if there is no high element. Used to
6735 determine whether or not a new case label duplicates an old case
6736 label. We need a tree, rather than simply a hash table, because
6737 of the GNU case range extension. */
6740 /* Number of nested statement expressions within this switch
6741 statement; if nonzero, case and default labels may not
6743 unsigned int blocked_stmt_expr;
6745 /* Scope of outermost declarations of identifiers with variably
6746 modified type within this switch statement; if nonzero, case and
6747 default labels may not appear. */
6748 unsigned int blocked_vm;
6750 /* The next node on the stack. */
6751 struct c_switch *next;
6754 /* A stack of the currently active switch statements. The innermost
6755 switch statement is on the top of the stack. There is no need to
6756 mark the stack for garbage collection because it is only active
6757 during the processing of the body of a function, and we never
6758 collect at that point. */
6760 struct c_switch *c_switch_stack;
6762 /* Start a C switch statement, testing expression EXP. Return the new
6766 c_start_case (tree exp)
6768 enum tree_code code;
6769 tree type, orig_type = error_mark_node;
6770 struct c_switch *cs;
6772 if (exp != error_mark_node)
6774 code = TREE_CODE (TREE_TYPE (exp));
6775 orig_type = TREE_TYPE (exp);
6777 if (!INTEGRAL_TYPE_P (orig_type)
6778 && code != ERROR_MARK)
6780 error ("switch quantity not an integer");
6781 exp = integer_zero_node;
6782 orig_type = error_mark_node;
6786 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6788 if (!in_system_header
6789 && (type == long_integer_type_node
6790 || type == long_unsigned_type_node))
6791 warning (OPT_Wtraditional, "%<long%> switch expression not "
6792 "converted to %<int%> in ISO C");
6794 exp = default_conversion (exp);
6795 type = TREE_TYPE (exp);
6799 /* Add this new SWITCH_EXPR to the stack. */
6800 cs = XNEW (struct c_switch);
6801 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
6802 cs->orig_type = orig_type;
6803 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6804 cs->blocked_stmt_expr = 0;
6806 cs->next = c_switch_stack;
6807 c_switch_stack = cs;
6809 return add_stmt (cs->switch_expr);
6812 /* Process a case label. */
6815 do_case (tree low_value, tree high_value)
6817 tree label = NULL_TREE;
6819 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
6820 && !c_switch_stack->blocked_vm)
6822 label = c_add_case_label (c_switch_stack->cases,
6823 SWITCH_COND (c_switch_stack->switch_expr),
6824 c_switch_stack->orig_type,
6825 low_value, high_value);
6826 if (label == error_mark_node)
6829 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
6832 error ("case label in statement expression not containing "
6833 "enclosing switch statement");
6835 error ("%<default%> label in statement expression not containing "
6836 "enclosing switch statement");
6838 else if (c_switch_stack && c_switch_stack->blocked_vm)
6841 error ("case label in scope of identifier with variably modified "
6842 "type not containing enclosing switch statement");
6844 error ("%<default%> label in scope of identifier with variably "
6845 "modified type not containing enclosing switch statement");
6848 error ("case label not within a switch statement");
6850 error ("%<default%> label not within a switch statement");
6855 /* Finish the switch statement. */
6858 c_finish_case (tree body)
6860 struct c_switch *cs = c_switch_stack;
6861 location_t switch_location;
6863 SWITCH_BODY (cs->switch_expr) = body;
6865 /* We must not be within a statement expression nested in the switch
6866 at this point; we might, however, be within the scope of an
6867 identifier with variably modified type nested in the switch. */
6868 gcc_assert (!cs->blocked_stmt_expr);
6870 /* Emit warnings as needed. */
6871 if (EXPR_HAS_LOCATION (cs->switch_expr))
6872 switch_location = EXPR_LOCATION (cs->switch_expr);
6874 switch_location = input_location;
6875 c_do_switch_warnings (cs->cases, switch_location,
6876 TREE_TYPE (cs->switch_expr),
6877 SWITCH_COND (cs->switch_expr));
6879 /* Pop the stack. */
6880 c_switch_stack = cs->next;
6881 splay_tree_delete (cs->cases);
6885 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6886 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6887 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6888 statement, and was not surrounded with parenthesis. */
6891 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6892 tree else_block, bool nested_if)
6896 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6897 if (warn_parentheses && nested_if && else_block == NULL)
6899 tree inner_if = then_block;
6901 /* We know from the grammar productions that there is an IF nested
6902 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6903 it might not be exactly THEN_BLOCK, but should be the last
6904 non-container statement within. */
6906 switch (TREE_CODE (inner_if))
6911 inner_if = BIND_EXPR_BODY (inner_if);
6913 case STATEMENT_LIST:
6914 inner_if = expr_last (then_block);
6916 case TRY_FINALLY_EXPR:
6917 case TRY_CATCH_EXPR:
6918 inner_if = TREE_OPERAND (inner_if, 0);
6925 if (COND_EXPR_ELSE (inner_if))
6926 warning (0, "%Hsuggest explicit braces to avoid ambiguous %<else%>",
6930 /* Diagnose ";" via the special empty statement node that we create. */
6933 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6936 warning (0, "%Hempty body in an if-statement",
6937 EXPR_LOCUS (then_block));
6938 then_block = alloc_stmt_list ();
6941 && TREE_CODE (else_block) == NOP_EXPR
6942 && !TREE_TYPE (else_block))
6944 warning (0, "%Hempty body in an else-statement",
6945 EXPR_LOCUS (else_block));
6946 else_block = alloc_stmt_list ();
6950 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
6951 SET_EXPR_LOCATION (stmt, if_locus);
6955 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6956 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6957 is false for DO loops. INCR is the FOR increment expression. BODY is
6958 the statement controlled by the loop. BLAB is the break label. CLAB is
6959 the continue label. Everything is allowed to be NULL. */
6962 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6963 tree blab, tree clab, bool cond_is_first)
6965 tree entry = NULL, exit = NULL, t;
6967 /* If the condition is zero don't generate a loop construct. */
6968 if (cond && integer_zerop (cond))
6972 t = build_and_jump (&blab);
6973 SET_EXPR_LOCATION (t, start_locus);
6979 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6981 /* If we have an exit condition, then we build an IF with gotos either
6982 out of the loop, or to the top of it. If there's no exit condition,
6983 then we just build a jump back to the top. */
6984 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6986 if (cond && !integer_nonzerop (cond))
6988 /* Canonicalize the loop condition to the end. This means
6989 generating a branch to the loop condition. Reuse the
6990 continue label, if possible. */
6995 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6996 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
6999 t = build1 (GOTO_EXPR, void_type_node, clab);
7000 SET_EXPR_LOCATION (t, start_locus);
7004 t = build_and_jump (&blab);
7005 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
7008 SET_EXPR_LOCATION (exit, start_locus);
7010 SET_EXPR_LOCATION (exit, input_location);
7019 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7027 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7031 c_finish_bc_stmt (tree *label_p, bool is_break)
7034 tree label = *label_p;
7036 /* In switch statements break is sometimes stylistically used after
7037 a return statement. This can lead to spurious warnings about
7038 control reaching the end of a non-void function when it is
7039 inlined. Note that we are calling block_may_fallthru with
7040 language specific tree nodes; this works because
7041 block_may_fallthru returns true when given something it does not
7043 skip = !block_may_fallthru (cur_stmt_list);
7048 *label_p = label = create_artificial_label ();
7050 else if (TREE_CODE (label) != LABEL_DECL)
7053 error ("break statement not within loop or switch");
7055 error ("continue statement not within a loop");
7062 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7065 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7068 emit_side_effect_warnings (tree expr)
7070 if (expr == error_mark_node)
7072 else if (!TREE_SIDE_EFFECTS (expr))
7074 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7075 warning (0, "%Hstatement with no effect",
7076 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7078 else if (warn_unused_value)
7079 warn_if_unused_value (expr, input_location);
7082 /* Process an expression as if it were a complete statement. Emit
7083 diagnostics, but do not call ADD_STMT. */
7086 c_process_expr_stmt (tree expr)
7091 if (warn_sequence_point)
7092 verify_sequence_points (expr);
7094 if (TREE_TYPE (expr) != error_mark_node
7095 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7096 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7097 error ("expression statement has incomplete type");
7099 /* If we're not processing a statement expression, warn about unused values.
7100 Warnings for statement expressions will be emitted later, once we figure
7101 out which is the result. */
7102 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7103 && (extra_warnings || warn_unused_value))
7104 emit_side_effect_warnings (expr);
7106 /* If the expression is not of a type to which we cannot assign a line
7107 number, wrap the thing in a no-op NOP_EXPR. */
7108 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7109 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7112 SET_EXPR_LOCATION (expr, input_location);
7117 /* Emit an expression as a statement. */
7120 c_finish_expr_stmt (tree expr)
7123 return add_stmt (c_process_expr_stmt (expr));
7128 /* Do the opposite and emit a statement as an expression. To begin,
7129 create a new binding level and return it. */
7132 c_begin_stmt_expr (void)
7135 struct c_label_context_se *nstack;
7136 struct c_label_list *glist;
7138 /* We must force a BLOCK for this level so that, if it is not expanded
7139 later, there is a way to turn off the entire subtree of blocks that
7140 are contained in it. */
7142 ret = c_begin_compound_stmt (true);
7145 c_switch_stack->blocked_stmt_expr++;
7146 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7148 for (glist = label_context_stack_se->labels_used;
7150 glist = glist->next)
7152 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7154 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7155 nstack->labels_def = NULL;
7156 nstack->labels_used = NULL;
7157 nstack->next = label_context_stack_se;
7158 label_context_stack_se = nstack;
7160 /* Mark the current statement list as belonging to a statement list. */
7161 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7167 c_finish_stmt_expr (tree body)
7169 tree last, type, tmp, val;
7171 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7173 body = c_end_compound_stmt (body, true);
7176 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7177 c_switch_stack->blocked_stmt_expr--;
7179 /* It is no longer possible to jump to labels defined within this
7180 statement expression. */
7181 for (dlist = label_context_stack_se->labels_def;
7183 dlist = dlist->next)
7185 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7187 /* It is again possible to define labels with a goto just outside
7188 this statement expression. */
7189 for (glist = label_context_stack_se->next->labels_used;
7191 glist = glist->next)
7193 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7196 if (glist_prev != NULL)
7197 glist_prev->next = label_context_stack_se->labels_used;
7199 label_context_stack_se->next->labels_used
7200 = label_context_stack_se->labels_used;
7201 label_context_stack_se = label_context_stack_se->next;
7203 /* Locate the last statement in BODY. See c_end_compound_stmt
7204 about always returning a BIND_EXPR. */
7205 last_p = &BIND_EXPR_BODY (body);
7206 last = BIND_EXPR_BODY (body);
7209 if (TREE_CODE (last) == STATEMENT_LIST)
7211 tree_stmt_iterator i;
7213 /* This can happen with degenerate cases like ({ }). No value. */
7214 if (!TREE_SIDE_EFFECTS (last))
7217 /* If we're supposed to generate side effects warnings, process
7218 all of the statements except the last. */
7219 if (extra_warnings || warn_unused_value)
7221 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7222 emit_side_effect_warnings (tsi_stmt (i));
7225 i = tsi_last (last);
7226 last_p = tsi_stmt_ptr (i);
7230 /* If the end of the list is exception related, then the list was split
7231 by a call to push_cleanup. Continue searching. */
7232 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7233 || TREE_CODE (last) == TRY_CATCH_EXPR)
7235 last_p = &TREE_OPERAND (last, 0);
7237 goto continue_searching;
7240 /* In the case that the BIND_EXPR is not necessary, return the
7241 expression out from inside it. */
7242 if (last == error_mark_node
7243 || (last == BIND_EXPR_BODY (body)
7244 && BIND_EXPR_VARS (body) == NULL))
7247 /* Extract the type of said expression. */
7248 type = TREE_TYPE (last);
7250 /* If we're not returning a value at all, then the BIND_EXPR that
7251 we already have is a fine expression to return. */
7252 if (!type || VOID_TYPE_P (type))
7255 /* Now that we've located the expression containing the value, it seems
7256 silly to make voidify_wrapper_expr repeat the process. Create a
7257 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7258 tmp = create_tmp_var_raw (type, NULL);
7260 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7261 tree_expr_nonnegative_p giving up immediately. */
7263 if (TREE_CODE (val) == NOP_EXPR
7264 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7265 val = TREE_OPERAND (val, 0);
7267 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7268 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7270 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7273 /* Begin the scope of an identifier of variably modified type, scope
7274 number SCOPE. Jumping from outside this scope to inside it is not
7278 c_begin_vm_scope (unsigned int scope)
7280 struct c_label_context_vm *nstack;
7281 struct c_label_list *glist;
7283 gcc_assert (scope > 0);
7284 if (c_switch_stack && !c_switch_stack->blocked_vm)
7285 c_switch_stack->blocked_vm = scope;
7286 for (glist = label_context_stack_vm->labels_used;
7288 glist = glist->next)
7290 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7292 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7293 nstack->labels_def = NULL;
7294 nstack->labels_used = NULL;
7295 nstack->scope = scope;
7296 nstack->next = label_context_stack_vm;
7297 label_context_stack_vm = nstack;
7300 /* End a scope which may contain identifiers of variably modified
7301 type, scope number SCOPE. */
7304 c_end_vm_scope (unsigned int scope)
7306 if (label_context_stack_vm == NULL)
7308 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7309 c_switch_stack->blocked_vm = 0;
7310 /* We may have a number of nested scopes of identifiers with
7311 variably modified type, all at this depth. Pop each in turn. */
7312 while (label_context_stack_vm->scope == scope)
7314 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7316 /* It is no longer possible to jump to labels defined within this
7318 for (dlist = label_context_stack_vm->labels_def;
7320 dlist = dlist->next)
7322 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7324 /* It is again possible to define labels with a goto just outside
7326 for (glist = label_context_stack_vm->next->labels_used;
7328 glist = glist->next)
7330 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7333 if (glist_prev != NULL)
7334 glist_prev->next = label_context_stack_vm->labels_used;
7336 label_context_stack_vm->next->labels_used
7337 = label_context_stack_vm->labels_used;
7338 label_context_stack_vm = label_context_stack_vm->next;
7342 /* Begin and end compound statements. This is as simple as pushing
7343 and popping new statement lists from the tree. */
7346 c_begin_compound_stmt (bool do_scope)
7348 tree stmt = push_stmt_list ();
7355 c_end_compound_stmt (tree stmt, bool do_scope)
7361 if (c_dialect_objc ())
7362 objc_clear_super_receiver ();
7363 block = pop_scope ();
7366 stmt = pop_stmt_list (stmt);
7367 stmt = c_build_bind_expr (block, stmt);
7369 /* If this compound statement is nested immediately inside a statement
7370 expression, then force a BIND_EXPR to be created. Otherwise we'll
7371 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7372 STATEMENT_LISTs merge, and thus we can lose track of what statement
7375 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7376 && TREE_CODE (stmt) != BIND_EXPR)
7378 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7379 TREE_SIDE_EFFECTS (stmt) = 1;
7385 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7386 when the current scope is exited. EH_ONLY is true when this is not
7387 meant to apply to normal control flow transfer. */
7390 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7392 enum tree_code code;
7396 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7397 stmt = build_stmt (code, NULL, cleanup);
7399 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7400 list = push_stmt_list ();
7401 TREE_OPERAND (stmt, 0) = list;
7402 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7405 /* Build a binary-operation expression without default conversions.
7406 CODE is the kind of expression to build.
7407 This function differs from `build' in several ways:
7408 the data type of the result is computed and recorded in it,
7409 warnings are generated if arg data types are invalid,
7410 special handling for addition and subtraction of pointers is known,
7411 and some optimization is done (operations on narrow ints
7412 are done in the narrower type when that gives the same result).
7413 Constant folding is also done before the result is returned.
7415 Note that the operands will never have enumeral types, or function
7416 or array types, because either they will have the default conversions
7417 performed or they have both just been converted to some other type in which
7418 the arithmetic is to be done. */
7421 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7425 enum tree_code code0, code1;
7427 const char *invalid_op_diag;
7429 /* Expression code to give to the expression when it is built.
7430 Normally this is CODE, which is what the caller asked for,
7431 but in some special cases we change it. */
7432 enum tree_code resultcode = code;
7434 /* Data type in which the computation is to be performed.
7435 In the simplest cases this is the common type of the arguments. */
7436 tree result_type = NULL;
7438 /* Nonzero means operands have already been type-converted
7439 in whatever way is necessary.
7440 Zero means they need to be converted to RESULT_TYPE. */
7443 /* Nonzero means create the expression with this type, rather than
7445 tree build_type = 0;
7447 /* Nonzero means after finally constructing the expression
7448 convert it to this type. */
7449 tree final_type = 0;
7451 /* Nonzero if this is an operation like MIN or MAX which can
7452 safely be computed in short if both args are promoted shorts.
7453 Also implies COMMON.
7454 -1 indicates a bitwise operation; this makes a difference
7455 in the exact conditions for when it is safe to do the operation
7456 in a narrower mode. */
7459 /* Nonzero if this is a comparison operation;
7460 if both args are promoted shorts, compare the original shorts.
7461 Also implies COMMON. */
7462 int short_compare = 0;
7464 /* Nonzero if this is a right-shift operation, which can be computed on the
7465 original short and then promoted if the operand is a promoted short. */
7466 int short_shift = 0;
7468 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7471 /* True means types are compatible as far as ObjC is concerned. */
7476 op0 = default_conversion (orig_op0);
7477 op1 = default_conversion (orig_op1);
7485 type0 = TREE_TYPE (op0);
7486 type1 = TREE_TYPE (op1);
7488 /* The expression codes of the data types of the arguments tell us
7489 whether the arguments are integers, floating, pointers, etc. */
7490 code0 = TREE_CODE (type0);
7491 code1 = TREE_CODE (type1);
7493 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7494 STRIP_TYPE_NOPS (op0);
7495 STRIP_TYPE_NOPS (op1);
7497 /* If an error was already reported for one of the arguments,
7498 avoid reporting another error. */
7500 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7501 return error_mark_node;
7503 if ((invalid_op_diag
7504 = targetm.invalid_binary_op (code, type0, type1)))
7506 error (invalid_op_diag);
7507 return error_mark_node;
7510 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7515 /* Handle the pointer + int case. */
7516 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7517 return pointer_int_sum (PLUS_EXPR, op0, op1);
7518 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7519 return pointer_int_sum (PLUS_EXPR, op1, op0);
7525 /* Subtraction of two similar pointers.
7526 We must subtract them as integers, then divide by object size. */
7527 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7528 && comp_target_types (type0, type1))
7529 return pointer_diff (op0, op1);
7530 /* Handle pointer minus int. Just like pointer plus int. */
7531 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7532 return pointer_int_sum (MINUS_EXPR, op0, op1);
7541 case TRUNC_DIV_EXPR:
7543 case FLOOR_DIV_EXPR:
7544 case ROUND_DIV_EXPR:
7545 case EXACT_DIV_EXPR:
7546 /* Floating point division by zero is a legitimate way to obtain
7547 infinities and NaNs. */
7548 if (skip_evaluation == 0 && integer_zerop (op1))
7549 warning (OPT_Wdiv_by_zero, "division by zero");
7551 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7552 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7553 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7554 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7556 enum tree_code tcode0 = code0, tcode1 = code1;
7558 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7559 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7560 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7561 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7563 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7564 resultcode = RDIV_EXPR;
7566 /* Although it would be tempting to shorten always here, that
7567 loses on some targets, since the modulo instruction is
7568 undefined if the quotient can't be represented in the
7569 computation mode. We shorten only if unsigned or if
7570 dividing by something we know != -1. */
7571 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7572 || (TREE_CODE (op1) == INTEGER_CST
7573 && !integer_all_onesp (op1)));
7581 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7583 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7587 case TRUNC_MOD_EXPR:
7588 case FLOOR_MOD_EXPR:
7589 if (skip_evaluation == 0 && integer_zerop (op1))
7590 warning (OPT_Wdiv_by_zero, "division by zero");
7592 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7594 /* Although it would be tempting to shorten always here, that loses
7595 on some targets, since the modulo instruction is undefined if the
7596 quotient can't be represented in the computation mode. We shorten
7597 only if unsigned or if dividing by something we know != -1. */
7598 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7599 || (TREE_CODE (op1) == INTEGER_CST
7600 && !integer_all_onesp (op1)));
7605 case TRUTH_ANDIF_EXPR:
7606 case TRUTH_ORIF_EXPR:
7607 case TRUTH_AND_EXPR:
7609 case TRUTH_XOR_EXPR:
7610 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7611 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7612 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7613 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7615 /* Result of these operations is always an int,
7616 but that does not mean the operands should be
7617 converted to ints! */
7618 result_type = integer_type_node;
7619 op0 = c_common_truthvalue_conversion (op0);
7620 op1 = c_common_truthvalue_conversion (op1);
7625 /* Shift operations: result has same type as first operand;
7626 always convert second operand to int.
7627 Also set SHORT_SHIFT if shifting rightward. */
7630 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7632 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7634 if (tree_int_cst_sgn (op1) < 0)
7635 warning (0, "right shift count is negative");
7638 if (!integer_zerop (op1))
7641 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7642 warning (0, "right shift count >= width of type");
7646 /* Use the type of the value to be shifted. */
7647 result_type = type0;
7648 /* Convert the shift-count to an integer, regardless of size
7649 of value being shifted. */
7650 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7651 op1 = convert (integer_type_node, op1);
7652 /* Avoid converting op1 to result_type later. */
7658 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7660 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7662 if (tree_int_cst_sgn (op1) < 0)
7663 warning (0, "left shift count is negative");
7665 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7666 warning (0, "left shift count >= width of type");
7669 /* Use the type of the value to be shifted. */
7670 result_type = type0;
7671 /* Convert the shift-count to an integer, regardless of size
7672 of value being shifted. */
7673 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7674 op1 = convert (integer_type_node, op1);
7675 /* Avoid converting op1 to result_type later. */
7682 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7683 warning (OPT_Wfloat_equal,
7684 "comparing floating point with == or != is unsafe");
7685 /* Result of comparison is always int,
7686 but don't convert the args to int! */
7687 build_type = integer_type_node;
7688 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7689 || code0 == COMPLEX_TYPE)
7690 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7691 || code1 == COMPLEX_TYPE))
7693 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7695 tree tt0 = TREE_TYPE (type0);
7696 tree tt1 = TREE_TYPE (type1);
7697 /* Anything compares with void *. void * compares with anything.
7698 Otherwise, the targets must be compatible
7699 and both must be object or both incomplete. */
7700 if (comp_target_types (type0, type1))
7701 result_type = common_pointer_type (type0, type1);
7702 else if (VOID_TYPE_P (tt0))
7704 /* op0 != orig_op0 detects the case of something
7705 whose value is 0 but which isn't a valid null ptr const. */
7706 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7707 && TREE_CODE (tt1) == FUNCTION_TYPE)
7708 pedwarn ("ISO C forbids comparison of %<void *%>"
7709 " with function pointer");
7711 else if (VOID_TYPE_P (tt1))
7713 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7714 && TREE_CODE (tt0) == FUNCTION_TYPE)
7715 pedwarn ("ISO C forbids comparison of %<void *%>"
7716 " with function pointer");
7719 /* Avoid warning about the volatile ObjC EH puts on decls. */
7721 pedwarn ("comparison of distinct pointer types lacks a cast");
7723 if (result_type == NULL_TREE)
7724 result_type = ptr_type_node;
7726 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7727 && integer_zerop (op1))
7728 result_type = type0;
7729 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7730 && integer_zerop (op0))
7731 result_type = type1;
7732 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7734 result_type = type0;
7735 pedwarn ("comparison between pointer and integer");
7737 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7739 result_type = type1;
7740 pedwarn ("comparison between pointer and integer");
7748 build_type = integer_type_node;
7749 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7750 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7752 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7754 if (comp_target_types (type0, type1))
7756 result_type = common_pointer_type (type0, type1);
7757 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7758 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7759 pedwarn ("comparison of complete and incomplete pointers");
7761 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7762 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7766 result_type = ptr_type_node;
7767 pedwarn ("comparison of distinct pointer types lacks a cast");
7770 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7771 && integer_zerop (op1))
7773 result_type = type0;
7774 if (pedantic || extra_warnings)
7775 pedwarn ("ordered comparison of pointer with integer zero");
7777 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7778 && integer_zerop (op0))
7780 result_type = type1;
7782 pedwarn ("ordered comparison of pointer with integer zero");
7784 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7786 result_type = type0;
7787 pedwarn ("comparison between pointer and integer");
7789 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7791 result_type = type1;
7792 pedwarn ("comparison between pointer and integer");
7800 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7801 return error_mark_node;
7803 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
7804 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
7805 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
7806 TREE_TYPE (type1))))
7808 binary_op_error (code);
7809 return error_mark_node;
7812 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7813 || code0 == VECTOR_TYPE)
7815 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7816 || code1 == VECTOR_TYPE))
7818 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7820 if (shorten || common || short_compare)
7821 result_type = c_common_type (type0, type1);
7823 /* For certain operations (which identify themselves by shorten != 0)
7824 if both args were extended from the same smaller type,
7825 do the arithmetic in that type and then extend.
7827 shorten !=0 and !=1 indicates a bitwise operation.
7828 For them, this optimization is safe only if
7829 both args are zero-extended or both are sign-extended.
7830 Otherwise, we might change the result.
7831 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7832 but calculated in (unsigned short) it would be (unsigned short)-1. */
7834 if (shorten && none_complex)
7836 int unsigned0, unsigned1;
7837 tree arg0 = get_narrower (op0, &unsigned0);
7838 tree arg1 = get_narrower (op1, &unsigned1);
7839 /* UNS is 1 if the operation to be done is an unsigned one. */
7840 int uns = TYPE_UNSIGNED (result_type);
7843 final_type = result_type;
7845 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7846 but it *requires* conversion to FINAL_TYPE. */
7848 if ((TYPE_PRECISION (TREE_TYPE (op0))
7849 == TYPE_PRECISION (TREE_TYPE (arg0)))
7850 && TREE_TYPE (op0) != final_type)
7851 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7852 if ((TYPE_PRECISION (TREE_TYPE (op1))
7853 == TYPE_PRECISION (TREE_TYPE (arg1)))
7854 && TREE_TYPE (op1) != final_type)
7855 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7857 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7859 /* For bitwise operations, signedness of nominal type
7860 does not matter. Consider only how operands were extended. */
7864 /* Note that in all three cases below we refrain from optimizing
7865 an unsigned operation on sign-extended args.
7866 That would not be valid. */
7868 /* Both args variable: if both extended in same way
7869 from same width, do it in that width.
7870 Do it unsigned if args were zero-extended. */
7871 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7872 < TYPE_PRECISION (result_type))
7873 && (TYPE_PRECISION (TREE_TYPE (arg1))
7874 == TYPE_PRECISION (TREE_TYPE (arg0)))
7875 && unsigned0 == unsigned1
7876 && (unsigned0 || !uns))
7878 = c_common_signed_or_unsigned_type
7879 (unsigned0, c_common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7880 else if (TREE_CODE (arg0) == INTEGER_CST
7881 && (unsigned1 || !uns)
7882 && (TYPE_PRECISION (TREE_TYPE (arg1))
7883 < TYPE_PRECISION (result_type))
7885 = c_common_signed_or_unsigned_type (unsigned1,
7887 int_fits_type_p (arg0, type)))
7889 else if (TREE_CODE (arg1) == INTEGER_CST
7890 && (unsigned0 || !uns)
7891 && (TYPE_PRECISION (TREE_TYPE (arg0))
7892 < TYPE_PRECISION (result_type))
7894 = c_common_signed_or_unsigned_type (unsigned0,
7896 int_fits_type_p (arg1, type)))
7900 /* Shifts can be shortened if shifting right. */
7905 tree arg0 = get_narrower (op0, &unsigned_arg);
7907 final_type = result_type;
7909 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7910 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7912 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7913 /* We can shorten only if the shift count is less than the
7914 number of bits in the smaller type size. */
7915 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7916 /* We cannot drop an unsigned shift after sign-extension. */
7917 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7919 /* Do an unsigned shift if the operand was zero-extended. */
7921 = c_common_signed_or_unsigned_type (unsigned_arg,
7923 /* Convert value-to-be-shifted to that type. */
7924 if (TREE_TYPE (op0) != result_type)
7925 op0 = convert (result_type, op0);
7930 /* Comparison operations are shortened too but differently.
7931 They identify themselves by setting short_compare = 1. */
7935 /* Don't write &op0, etc., because that would prevent op0
7936 from being kept in a register.
7937 Instead, make copies of the our local variables and
7938 pass the copies by reference, then copy them back afterward. */
7939 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7940 enum tree_code xresultcode = resultcode;
7942 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7947 op0 = xop0, op1 = xop1;
7949 resultcode = xresultcode;
7951 if (warn_sign_compare && skip_evaluation == 0)
7953 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7954 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7955 int unsignedp0, unsignedp1;
7956 tree primop0 = get_narrower (op0, &unsignedp0);
7957 tree primop1 = get_narrower (op1, &unsignedp1);
7961 STRIP_TYPE_NOPS (xop0);
7962 STRIP_TYPE_NOPS (xop1);
7964 /* Give warnings for comparisons between signed and unsigned
7965 quantities that may fail.
7967 Do the checking based on the original operand trees, so that
7968 casts will be considered, but default promotions won't be.
7970 Do not warn if the comparison is being done in a signed type,
7971 since the signed type will only be chosen if it can represent
7972 all the values of the unsigned type. */
7973 if (!TYPE_UNSIGNED (result_type))
7975 /* Do not warn if both operands are the same signedness. */
7976 else if (op0_signed == op1_signed)
7983 sop = xop0, uop = xop1;
7985 sop = xop1, uop = xop0;
7987 /* Do not warn if the signed quantity is an
7988 unsuffixed integer literal (or some static
7989 constant expression involving such literals or a
7990 conditional expression involving such literals)
7991 and it is non-negative. */
7992 if (tree_expr_nonnegative_p (sop))
7994 /* Do not warn if the comparison is an equality operation,
7995 the unsigned quantity is an integral constant, and it
7996 would fit in the result if the result were signed. */
7997 else if (TREE_CODE (uop) == INTEGER_CST
7998 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8000 (uop, c_common_signed_type (result_type)))
8002 /* Do not warn if the unsigned quantity is an enumeration
8003 constant and its maximum value would fit in the result
8004 if the result were signed. */
8005 else if (TREE_CODE (uop) == INTEGER_CST
8006 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8008 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8009 c_common_signed_type (result_type)))
8012 warning (0, "comparison between signed and unsigned");
8015 /* Warn if two unsigned values are being compared in a size
8016 larger than their original size, and one (and only one) is the
8017 result of a `~' operator. This comparison will always fail.
8019 Also warn if one operand is a constant, and the constant
8020 does not have all bits set that are set in the ~ operand
8021 when it is extended. */
8023 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8024 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8026 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8027 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8030 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8033 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8036 HOST_WIDE_INT constant, mask;
8037 int unsignedp, bits;
8039 if (host_integerp (primop0, 0))
8042 unsignedp = unsignedp1;
8043 constant = tree_low_cst (primop0, 0);
8048 unsignedp = unsignedp0;
8049 constant = tree_low_cst (primop1, 0);
8052 bits = TYPE_PRECISION (TREE_TYPE (primop));
8053 if (bits < TYPE_PRECISION (result_type)
8054 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8056 mask = (~(HOST_WIDE_INT) 0) << bits;
8057 if ((mask & constant) != mask)
8058 warning (0, "comparison of promoted ~unsigned with constant");
8061 else if (unsignedp0 && unsignedp1
8062 && (TYPE_PRECISION (TREE_TYPE (primop0))
8063 < TYPE_PRECISION (result_type))
8064 && (TYPE_PRECISION (TREE_TYPE (primop1))
8065 < TYPE_PRECISION (result_type)))
8066 warning (0, "comparison of promoted ~unsigned with unsigned");
8072 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8073 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8074 Then the expression will be built.
8075 It will be given type FINAL_TYPE if that is nonzero;
8076 otherwise, it will be given type RESULT_TYPE. */
8080 binary_op_error (code);
8081 return error_mark_node;
8086 if (TREE_TYPE (op0) != result_type)
8087 op0 = convert (result_type, op0);
8088 if (TREE_TYPE (op1) != result_type)
8089 op1 = convert (result_type, op1);
8091 /* This can happen if one operand has a vector type, and the other
8092 has a different type. */
8093 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8094 return error_mark_node;
8097 if (build_type == NULL_TREE)
8098 build_type = result_type;
8101 tree result = build2 (resultcode, build_type, op0, op1);
8103 /* Treat expressions in initializers specially as they can't trap. */
8104 result = require_constant_value ? fold_initializer (result)
8107 if (final_type != 0)
8108 result = convert (final_type, result);
8114 /* Convert EXPR to be a truth-value, validating its type for this
8118 c_objc_common_truthvalue_conversion (tree expr)
8120 switch (TREE_CODE (TREE_TYPE (expr)))
8123 error ("used array that cannot be converted to pointer where scalar is required");
8124 return error_mark_node;
8127 error ("used struct type value where scalar is required");
8128 return error_mark_node;
8131 error ("used union type value where scalar is required");
8132 return error_mark_node;
8141 /* ??? Should we also give an error for void and vectors rather than
8142 leaving those to give errors later? */
8143 return c_common_truthvalue_conversion (expr);