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);
2800 argtype = TREE_TYPE (arg);
2801 val = build1 (code, argtype, arg);
2802 return require_constant_value ? fold_initializer (val) : fold (val);
2805 /* Return nonzero if REF is an lvalue valid for this language.
2806 Lvalues can be assigned, unless their type has TYPE_READONLY.
2807 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2812 enum tree_code code = TREE_CODE (ref);
2819 return lvalue_p (TREE_OPERAND (ref, 0));
2821 case COMPOUND_LITERAL_EXPR:
2831 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2832 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2835 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2842 /* Give an error for storing in something that is 'const'. */
2845 readonly_error (tree arg, enum lvalue_use use)
2847 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2848 /* Using this macro rather than (for example) arrays of messages
2849 ensures that all the format strings are checked at compile
2851 #define READONLY_MSG(A, I, D) (use == lv_assign \
2853 : (use == lv_increment ? (I) : (D)))
2854 if (TREE_CODE (arg) == COMPONENT_REF)
2856 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2857 readonly_error (TREE_OPERAND (arg, 0), use);
2859 error (READONLY_MSG (G_("assignment of read-only member %qD"),
2860 G_("increment of read-only member %qD"),
2861 G_("decrement of read-only member %qD")),
2862 TREE_OPERAND (arg, 1));
2864 else if (TREE_CODE (arg) == VAR_DECL)
2865 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
2866 G_("increment of read-only variable %qD"),
2867 G_("decrement of read-only variable %qD")),
2870 error (READONLY_MSG (G_("assignment of read-only location"),
2871 G_("increment of read-only location"),
2872 G_("decrement of read-only location")));
2876 /* Return nonzero if REF is an lvalue valid for this language;
2877 otherwise, print an error message and return zero. USE says
2878 how the lvalue is being used and so selects the error message. */
2881 lvalue_or_else (tree ref, enum lvalue_use use)
2883 int win = lvalue_p (ref);
2891 /* Mark EXP saying that we need to be able to take the
2892 address of it; it should not be allocated in a register.
2893 Returns true if successful. */
2896 c_mark_addressable (tree exp)
2901 switch (TREE_CODE (x))
2904 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2907 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2911 /* ... fall through ... */
2917 x = TREE_OPERAND (x, 0);
2920 case COMPOUND_LITERAL_EXPR:
2922 TREE_ADDRESSABLE (x) = 1;
2929 if (C_DECL_REGISTER (x)
2930 && DECL_NONLOCAL (x))
2932 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2935 ("global register variable %qD used in nested function", x);
2938 pedwarn ("register variable %qD used in nested function", x);
2940 else if (C_DECL_REGISTER (x))
2942 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2943 error ("address of global register variable %qD requested", x);
2945 error ("address of register variable %qD requested", x);
2951 TREE_ADDRESSABLE (x) = 1;
2958 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2961 build_conditional_expr (tree ifexp, tree op1, tree op2)
2965 enum tree_code code1;
2966 enum tree_code code2;
2967 tree result_type = NULL;
2968 tree orig_op1 = op1, orig_op2 = op2;
2970 /* Promote both alternatives. */
2972 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2973 op1 = default_conversion (op1);
2974 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2975 op2 = default_conversion (op2);
2977 if (TREE_CODE (ifexp) == ERROR_MARK
2978 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2979 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2980 return error_mark_node;
2982 type1 = TREE_TYPE (op1);
2983 code1 = TREE_CODE (type1);
2984 type2 = TREE_TYPE (op2);
2985 code2 = TREE_CODE (type2);
2987 /* C90 does not permit non-lvalue arrays in conditional expressions.
2988 In C99 they will be pointers by now. */
2989 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2991 error ("non-lvalue array in conditional expression");
2992 return error_mark_node;
2995 /* Quickly detect the usual case where op1 and op2 have the same type
2997 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3000 result_type = type1;
3002 result_type = TYPE_MAIN_VARIANT (type1);
3004 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3005 || code1 == COMPLEX_TYPE)
3006 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3007 || code2 == COMPLEX_TYPE))
3009 result_type = c_common_type (type1, type2);
3011 /* If -Wsign-compare, warn here if type1 and type2 have
3012 different signedness. We'll promote the signed to unsigned
3013 and later code won't know it used to be different.
3014 Do this check on the original types, so that explicit casts
3015 will be considered, but default promotions won't. */
3016 if (warn_sign_compare && !skip_evaluation)
3018 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3019 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3021 if (unsigned_op1 ^ unsigned_op2)
3023 /* Do not warn if the result type is signed, since the
3024 signed type will only be chosen if it can represent
3025 all the values of the unsigned type. */
3026 if (!TYPE_UNSIGNED (result_type))
3028 /* Do not warn if the signed quantity is an unsuffixed
3029 integer literal (or some static constant expression
3030 involving such literals) and it is non-negative. */
3031 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3032 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3035 warning (0, "signed and unsigned type in conditional expression");
3039 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3041 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3042 pedwarn ("ISO C forbids conditional expr with only one void side");
3043 result_type = void_type_node;
3045 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3047 if (comp_target_types (type1, type2))
3048 result_type = common_pointer_type (type1, type2);
3049 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3050 && TREE_CODE (orig_op1) != NOP_EXPR)
3051 result_type = qualify_type (type2, type1);
3052 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3053 && TREE_CODE (orig_op2) != NOP_EXPR)
3054 result_type = qualify_type (type1, type2);
3055 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3057 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3058 pedwarn ("ISO C forbids conditional expr between "
3059 "%<void *%> and function pointer");
3060 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3061 TREE_TYPE (type2)));
3063 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3065 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3066 pedwarn ("ISO C forbids conditional expr between "
3067 "%<void *%> and function pointer");
3068 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3069 TREE_TYPE (type1)));
3073 pedwarn ("pointer type mismatch in conditional expression");
3074 result_type = build_pointer_type (void_type_node);
3077 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3079 if (!integer_zerop (op2))
3080 pedwarn ("pointer/integer type mismatch in conditional expression");
3083 op2 = null_pointer_node;
3085 result_type = type1;
3087 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3089 if (!integer_zerop (op1))
3090 pedwarn ("pointer/integer type mismatch in conditional expression");
3093 op1 = null_pointer_node;
3095 result_type = type2;
3100 if (flag_cond_mismatch)
3101 result_type = void_type_node;
3104 error ("type mismatch in conditional expression");
3105 return error_mark_node;
3109 /* Merge const and volatile flags of the incoming types. */
3111 = build_type_variant (result_type,
3112 TREE_READONLY (op1) || TREE_READONLY (op2),
3113 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3115 if (result_type != TREE_TYPE (op1))
3116 op1 = convert_and_check (result_type, op1);
3117 if (result_type != TREE_TYPE (op2))
3118 op2 = convert_and_check (result_type, op2);
3120 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3123 /* Return a compound expression that performs two expressions and
3124 returns the value of the second of them. */
3127 build_compound_expr (tree expr1, tree expr2)
3129 if (!TREE_SIDE_EFFECTS (expr1))
3131 /* The left-hand operand of a comma expression is like an expression
3132 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3133 any side-effects, unless it was explicitly cast to (void). */
3134 if (warn_unused_value)
3136 if (VOID_TYPE_P (TREE_TYPE (expr1))
3137 && TREE_CODE (expr1) == CONVERT_EXPR)
3139 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3140 && TREE_CODE (expr1) == COMPOUND_EXPR
3141 && TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR)
3142 ; /* (void) a, (void) b, c */
3144 warning (0, "left-hand operand of comma expression has no effect");
3148 /* With -Wunused, we should also warn if the left-hand operand does have
3149 side-effects, but computes a value which is not used. For example, in
3150 `foo() + bar(), baz()' the result of the `+' operator is not used,
3151 so we should issue a warning. */
3152 else if (warn_unused_value)
3153 warn_if_unused_value (expr1, input_location);
3155 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3158 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3161 build_c_cast (tree type, tree expr)
3165 if (type == error_mark_node || expr == error_mark_node)
3166 return error_mark_node;
3168 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3169 only in <protocol> qualifications. But when constructing cast expressions,
3170 the protocols do matter and must be kept around. */
3171 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3172 return build1 (NOP_EXPR, type, expr);
3174 type = TYPE_MAIN_VARIANT (type);
3176 if (TREE_CODE (type) == ARRAY_TYPE)
3178 error ("cast specifies array type");
3179 return error_mark_node;
3182 if (TREE_CODE (type) == FUNCTION_TYPE)
3184 error ("cast specifies function type");
3185 return error_mark_node;
3188 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3192 if (TREE_CODE (type) == RECORD_TYPE
3193 || TREE_CODE (type) == UNION_TYPE)
3194 pedwarn ("ISO C forbids casting nonscalar to the same type");
3197 else if (TREE_CODE (type) == UNION_TYPE)
3201 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3202 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3203 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3211 pedwarn ("ISO C forbids casts to union type");
3212 t = digest_init (type,
3213 build_constructor (type,
3214 build_tree_list (field, value)),
3216 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3217 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3220 error ("cast to union type from type not present in union");
3221 return error_mark_node;
3227 if (type == void_type_node)
3228 return build1 (CONVERT_EXPR, type, value);
3230 otype = TREE_TYPE (value);
3232 /* Optionally warn about potentially worrisome casts. */
3235 && TREE_CODE (type) == POINTER_TYPE
3236 && TREE_CODE (otype) == POINTER_TYPE)
3238 tree in_type = type;
3239 tree in_otype = otype;
3243 /* Check that the qualifiers on IN_TYPE are a superset of
3244 the qualifiers of IN_OTYPE. The outermost level of
3245 POINTER_TYPE nodes is uninteresting and we stop as soon
3246 as we hit a non-POINTER_TYPE node on either type. */
3249 in_otype = TREE_TYPE (in_otype);
3250 in_type = TREE_TYPE (in_type);
3252 /* GNU C allows cv-qualified function types. 'const'
3253 means the function is very pure, 'volatile' means it
3254 can't return. We need to warn when such qualifiers
3255 are added, not when they're taken away. */
3256 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3257 && TREE_CODE (in_type) == FUNCTION_TYPE)
3258 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3260 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3262 while (TREE_CODE (in_type) == POINTER_TYPE
3263 && TREE_CODE (in_otype) == POINTER_TYPE);
3266 warning (0, "cast adds new qualifiers to function type");
3269 /* There are qualifiers present in IN_OTYPE that are not
3270 present in IN_TYPE. */
3271 warning (0, "cast discards qualifiers from pointer target type");
3274 /* Warn about possible alignment problems. */
3275 if (STRICT_ALIGNMENT
3276 && TREE_CODE (type) == POINTER_TYPE
3277 && TREE_CODE (otype) == POINTER_TYPE
3278 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3279 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3280 /* Don't warn about opaque types, where the actual alignment
3281 restriction is unknown. */
3282 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3283 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3284 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3285 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3286 warning (OPT_Wcast_align,
3287 "cast increases required alignment of target type");
3289 if (TREE_CODE (type) == INTEGER_TYPE
3290 && TREE_CODE (otype) == POINTER_TYPE
3291 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3292 && !TREE_CONSTANT (value))
3293 warning (OPT_Wpointer_to_int_cast,
3294 "cast from pointer to integer of different size");
3296 if (TREE_CODE (value) == CALL_EXPR
3297 && TREE_CODE (type) != TREE_CODE (otype))
3298 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3299 "to non-matching type %qT", otype, type);
3301 if (TREE_CODE (type) == POINTER_TYPE
3302 && TREE_CODE (otype) == INTEGER_TYPE
3303 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3304 /* Don't warn about converting any constant. */
3305 && !TREE_CONSTANT (value))
3306 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3307 "of different size");
3309 if (flag_strict_aliasing && warn_strict_aliasing
3310 && TREE_CODE (type) == POINTER_TYPE
3311 && TREE_CODE (otype) == POINTER_TYPE
3312 && TREE_CODE (expr) == ADDR_EXPR
3313 && (DECL_P (TREE_OPERAND (expr, 0))
3314 || TREE_CODE (TREE_OPERAND (expr, 0)) == COMPONENT_REF)
3315 && !VOID_TYPE_P (TREE_TYPE (type)))
3317 /* Casting the address of an object to non void pointer. Warn
3318 if the cast breaks type based aliasing. */
3319 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3320 warning (OPT_Wstrict_aliasing, "type-punning to incomplete type "
3321 "might break strict-aliasing rules");
3324 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3325 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3327 if (!alias_sets_conflict_p (set1, set2))
3328 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
3329 "pointer will break strict-aliasing rules");
3330 else if (warn_strict_aliasing > 1
3331 && !alias_sets_might_conflict_p (set1, set2))
3332 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
3333 "pointer might break strict-aliasing rules");
3337 /* If pedantic, warn for conversions between function and object
3338 pointer types, except for converting a null pointer constant
3339 to function pointer type. */
3341 && TREE_CODE (type) == POINTER_TYPE
3342 && TREE_CODE (otype) == POINTER_TYPE
3343 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3344 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3345 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3348 && TREE_CODE (type) == POINTER_TYPE
3349 && TREE_CODE (otype) == POINTER_TYPE
3350 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3351 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3352 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3353 && TREE_CODE (expr) != NOP_EXPR))
3354 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3357 value = convert (type, value);
3359 /* Ignore any integer overflow caused by the cast. */
3360 if (TREE_CODE (value) == INTEGER_CST)
3362 /* If OVALUE had overflow set, then so will VALUE, so it
3363 is safe to overwrite. */
3364 if (CONSTANT_CLASS_P (ovalue))
3366 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3367 /* Similarly, constant_overflow cannot have become cleared. */
3368 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3371 TREE_OVERFLOW (value) = 0;
3375 /* Don't let a cast be an lvalue. */
3377 value = non_lvalue (value);
3382 /* Interpret a cast of expression EXPR to type TYPE. */
3384 c_cast_expr (struct c_type_name *type_name, tree expr)
3387 int saved_wsp = warn_strict_prototypes;
3389 /* This avoids warnings about unprototyped casts on
3390 integers. E.g. "#define SIG_DFL (void(*)())0". */
3391 if (TREE_CODE (expr) == INTEGER_CST)
3392 warn_strict_prototypes = 0;
3393 type = groktypename (type_name);
3394 warn_strict_prototypes = saved_wsp;
3396 return build_c_cast (type, expr);
3400 /* Build an assignment expression of lvalue LHS from value RHS.
3401 MODIFYCODE is the code for a binary operator that we use
3402 to combine the old value of LHS with RHS to get the new value.
3403 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3406 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3410 tree lhstype = TREE_TYPE (lhs);
3411 tree olhstype = lhstype;
3413 /* Types that aren't fully specified cannot be used in assignments. */
3414 lhs = require_complete_type (lhs);
3416 /* Avoid duplicate error messages from operands that had errors. */
3417 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3418 return error_mark_node;
3420 STRIP_TYPE_NOPS (rhs);
3424 /* If a binary op has been requested, combine the old LHS value with the RHS
3425 producing the value we should actually store into the LHS. */
3427 if (modifycode != NOP_EXPR)
3429 lhs = stabilize_reference (lhs);
3430 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3433 if (!lvalue_or_else (lhs, lv_assign))
3434 return error_mark_node;
3436 /* Give an error for storing in something that is 'const'. */
3438 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3439 || ((TREE_CODE (lhstype) == RECORD_TYPE
3440 || TREE_CODE (lhstype) == UNION_TYPE)
3441 && C_TYPE_FIELDS_READONLY (lhstype)))
3442 readonly_error (lhs, lv_assign);
3444 /* If storing into a structure or union member,
3445 it has probably been given type `int'.
3446 Compute the type that would go with
3447 the actual amount of storage the member occupies. */
3449 if (TREE_CODE (lhs) == COMPONENT_REF
3450 && (TREE_CODE (lhstype) == INTEGER_TYPE
3451 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3452 || TREE_CODE (lhstype) == REAL_TYPE
3453 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3454 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3456 /* If storing in a field that is in actuality a short or narrower than one,
3457 we must store in the field in its actual type. */
3459 if (lhstype != TREE_TYPE (lhs))
3461 lhs = copy_node (lhs);
3462 TREE_TYPE (lhs) = lhstype;
3465 /* Convert new value to destination type. */
3467 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3468 NULL_TREE, NULL_TREE, 0);
3469 if (TREE_CODE (newrhs) == ERROR_MARK)
3470 return error_mark_node;
3472 /* Emit ObjC write barrier, if necessary. */
3473 if (c_dialect_objc () && flag_objc_gc)
3475 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3480 /* Scan operands. */
3482 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3483 TREE_SIDE_EFFECTS (result) = 1;
3485 /* If we got the LHS in a different type for storing in,
3486 convert the result back to the nominal type of LHS
3487 so that the value we return always has the same type
3488 as the LHS argument. */
3490 if (olhstype == TREE_TYPE (result))
3492 return convert_for_assignment (olhstype, result, ic_assign,
3493 NULL_TREE, NULL_TREE, 0);
3496 /* Convert value RHS to type TYPE as preparation for an assignment
3497 to an lvalue of type TYPE.
3498 The real work of conversion is done by `convert'.
3499 The purpose of this function is to generate error messages
3500 for assignments that are not allowed in C.
3501 ERRTYPE says whether it is argument passing, assignment,
3502 initialization or return.
3504 FUNCTION is a tree for the function being called.
3505 PARMNUM is the number of the argument, for printing in error messages. */
3508 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3509 tree fundecl, tree function, int parmnum)
3511 enum tree_code codel = TREE_CODE (type);
3513 enum tree_code coder;
3514 tree rname = NULL_TREE;
3515 bool objc_ok = false;
3517 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3520 /* Change pointer to function to the function itself for
3522 if (TREE_CODE (function) == ADDR_EXPR
3523 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3524 function = TREE_OPERAND (function, 0);
3526 /* Handle an ObjC selector specially for diagnostics. */
3527 selector = objc_message_selector ();
3529 if (selector && parmnum > 2)
3536 /* This macro is used to emit diagnostics to ensure that all format
3537 strings are complete sentences, visible to gettext and checked at
3539 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3544 pedwarn (AR, parmnum, rname); \
3546 case ic_argpass_nonproto: \
3547 warning (0, AR, parmnum, rname); \
3559 gcc_unreachable (); \
3563 STRIP_TYPE_NOPS (rhs);
3565 if (optimize && TREE_CODE (rhs) == VAR_DECL
3566 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3567 rhs = decl_constant_value_for_broken_optimization (rhs);
3569 rhstype = TREE_TYPE (rhs);
3570 coder = TREE_CODE (rhstype);
3572 if (coder == ERROR_MARK)
3573 return error_mark_node;
3575 if (c_dialect_objc ())
3598 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3601 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3603 overflow_warning (rhs);
3607 if (coder == VOID_TYPE)
3609 /* Except for passing an argument to an unprototyped function,
3610 this is a constraint violation. When passing an argument to
3611 an unprototyped function, it is compile-time undefined;
3612 making it a constraint in that case was rejected in
3614 error ("void value not ignored as it ought to be");
3615 return error_mark_node;
3617 /* A type converts to a reference to it.
3618 This code doesn't fully support references, it's just for the
3619 special case of va_start and va_copy. */
3620 if (codel == REFERENCE_TYPE
3621 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3623 if (!lvalue_p (rhs))
3625 error ("cannot pass rvalue to reference parameter");
3626 return error_mark_node;
3628 if (!c_mark_addressable (rhs))
3629 return error_mark_node;
3630 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3632 /* We already know that these two types are compatible, but they
3633 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3634 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3635 likely to be va_list, a typedef to __builtin_va_list, which
3636 is different enough that it will cause problems later. */
3637 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3638 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3640 rhs = build1 (NOP_EXPR, type, rhs);
3643 /* Some types can interconvert without explicit casts. */
3644 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3645 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3646 return convert (type, rhs);
3647 /* Arithmetic types all interconvert, and enum is treated like int. */
3648 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3649 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3650 || codel == BOOLEAN_TYPE)
3651 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3652 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3653 || coder == BOOLEAN_TYPE))
3654 return convert_and_check (type, rhs);
3656 /* Conversion to a transparent union from its member types.
3657 This applies only to function arguments. */
3658 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3659 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3662 tree marginal_memb_type = 0;
3664 for (memb_types = TYPE_FIELDS (type); memb_types;
3665 memb_types = TREE_CHAIN (memb_types))
3667 tree memb_type = TREE_TYPE (memb_types);
3669 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3670 TYPE_MAIN_VARIANT (rhstype)))
3673 if (TREE_CODE (memb_type) != POINTER_TYPE)
3676 if (coder == POINTER_TYPE)
3678 tree ttl = TREE_TYPE (memb_type);
3679 tree ttr = TREE_TYPE (rhstype);
3681 /* Any non-function converts to a [const][volatile] void *
3682 and vice versa; otherwise, targets must be the same.
3683 Meanwhile, the lhs target must have all the qualifiers of
3685 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3686 || comp_target_types (memb_type, rhstype))
3688 /* If this type won't generate any warnings, use it. */
3689 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3690 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3691 && TREE_CODE (ttl) == FUNCTION_TYPE)
3692 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3693 == TYPE_QUALS (ttr))
3694 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3695 == TYPE_QUALS (ttl))))
3698 /* Keep looking for a better type, but remember this one. */
3699 if (!marginal_memb_type)
3700 marginal_memb_type = memb_type;
3704 /* Can convert integer zero to any pointer type. */
3705 if (integer_zerop (rhs)
3706 || (TREE_CODE (rhs) == NOP_EXPR
3707 && integer_zerop (TREE_OPERAND (rhs, 0))))
3709 rhs = null_pointer_node;
3714 if (memb_types || marginal_memb_type)
3718 /* We have only a marginally acceptable member type;
3719 it needs a warning. */
3720 tree ttl = TREE_TYPE (marginal_memb_type);
3721 tree ttr = TREE_TYPE (rhstype);
3723 /* Const and volatile mean something different for function
3724 types, so the usual warnings are not appropriate. */
3725 if (TREE_CODE (ttr) == FUNCTION_TYPE
3726 && TREE_CODE (ttl) == FUNCTION_TYPE)
3728 /* Because const and volatile on functions are
3729 restrictions that say the function will not do
3730 certain things, it is okay to use a const or volatile
3731 function where an ordinary one is wanted, but not
3733 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3734 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3735 "makes qualified function "
3736 "pointer from unqualified"),
3737 G_("assignment makes qualified "
3738 "function pointer from "
3740 G_("initialization makes qualified "
3741 "function pointer from "
3743 G_("return makes qualified function "
3744 "pointer from unqualified"));
3746 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3747 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3748 "qualifiers from pointer target type"),
3749 G_("assignment discards qualifiers "
3750 "from pointer target type"),
3751 G_("initialization discards qualifiers "
3752 "from pointer target type"),
3753 G_("return discards qualifiers from "
3754 "pointer target type"));
3757 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3758 pedwarn ("ISO C prohibits argument conversion to union type");
3760 return build1 (NOP_EXPR, type, rhs);
3764 /* Conversions among pointers */
3765 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3766 && (coder == codel))
3768 tree ttl = TREE_TYPE (type);
3769 tree ttr = TREE_TYPE (rhstype);
3772 bool is_opaque_pointer;
3773 int target_cmp = 0; /* Cache comp_target_types () result. */
3775 if (TREE_CODE (mvl) != ARRAY_TYPE)
3776 mvl = TYPE_MAIN_VARIANT (mvl);
3777 if (TREE_CODE (mvr) != ARRAY_TYPE)
3778 mvr = TYPE_MAIN_VARIANT (mvr);
3779 /* Opaque pointers are treated like void pointers. */
3780 is_opaque_pointer = (targetm.vector_opaque_p (type)
3781 || targetm.vector_opaque_p (rhstype))
3782 && TREE_CODE (ttl) == VECTOR_TYPE
3783 && TREE_CODE (ttr) == VECTOR_TYPE;
3785 /* C++ does not allow the implicit conversion void* -> T*. However,
3786 for the purpose of reducing the number of false positives, we
3787 tolerate the special case of
3791 where NULL is typically defined in C to be '(void *) 0'. */
3792 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
3793 warning (OPT_Wc___compat, "request for implicit conversion from "
3794 "%qT to %qT not permitted in C++", rhstype, type);
3796 /* Any non-function converts to a [const][volatile] void *
3797 and vice versa; otherwise, targets must be the same.
3798 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3799 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3800 || (target_cmp = comp_target_types (type, rhstype))
3801 || is_opaque_pointer
3802 || (c_common_unsigned_type (mvl)
3803 == c_common_unsigned_type (mvr)))
3806 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3809 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3810 which are not ANSI null ptr constants. */
3811 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3812 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3813 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
3814 "%qE between function pointer "
3816 G_("ISO C forbids assignment between "
3817 "function pointer and %<void *%>"),
3818 G_("ISO C forbids initialization between "
3819 "function pointer and %<void *%>"),
3820 G_("ISO C forbids return between function "
3821 "pointer and %<void *%>"));
3822 /* Const and volatile mean something different for function types,
3823 so the usual warnings are not appropriate. */
3824 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3825 && TREE_CODE (ttl) != FUNCTION_TYPE)
3827 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3829 /* Types differing only by the presence of the 'volatile'
3830 qualifier are acceptable if the 'volatile' has been added
3831 in by the Objective-C EH machinery. */
3832 if (!objc_type_quals_match (ttl, ttr))
3833 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3834 "qualifiers from pointer target type"),
3835 G_("assignment discards qualifiers "
3836 "from pointer target type"),
3837 G_("initialization discards qualifiers "
3838 "from pointer target type"),
3839 G_("return discards qualifiers from "
3840 "pointer target type"));
3842 /* If this is not a case of ignoring a mismatch in signedness,
3844 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3847 /* If there is a mismatch, do warn. */
3848 else if (warn_pointer_sign)
3849 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
3850 "%d of %qE differ in signedness"),
3851 G_("pointer targets in assignment "
3852 "differ in signedness"),
3853 G_("pointer targets in initialization "
3854 "differ in signedness"),
3855 G_("pointer targets in return differ "
3858 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3859 && TREE_CODE (ttr) == FUNCTION_TYPE)
3861 /* Because const and volatile on functions are restrictions
3862 that say the function will not do certain things,
3863 it is okay to use a const or volatile function
3864 where an ordinary one is wanted, but not vice-versa. */
3865 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3866 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3867 "qualified function pointer "
3868 "from unqualified"),
3869 G_("assignment makes qualified function "
3870 "pointer from unqualified"),
3871 G_("initialization makes qualified "
3872 "function pointer from unqualified"),
3873 G_("return makes qualified function "
3874 "pointer from unqualified"));
3878 /* Avoid warning about the volatile ObjC EH puts on decls. */
3880 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
3881 "incompatible pointer type"),
3882 G_("assignment from incompatible pointer type"),
3883 G_("initialization from incompatible "
3885 G_("return from incompatible pointer type"));
3887 return convert (type, rhs);
3889 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3891 /* ??? This should not be an error when inlining calls to
3892 unprototyped functions. */
3893 error ("invalid use of non-lvalue array");
3894 return error_mark_node;
3896 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3898 /* An explicit constant 0 can convert to a pointer,
3899 or one that results from arithmetic, even including
3900 a cast to integer type. */
3901 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3903 !(TREE_CODE (rhs) == NOP_EXPR
3904 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3905 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3906 && integer_zerop (TREE_OPERAND (rhs, 0))))
3907 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3908 "pointer from integer without a cast"),
3909 G_("assignment makes pointer from integer "
3911 G_("initialization makes pointer from "
3912 "integer without a cast"),
3913 G_("return makes pointer from integer "
3916 return convert (type, rhs);
3918 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3920 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
3921 "from pointer without a cast"),
3922 G_("assignment makes integer from pointer "
3924 G_("initialization makes integer from pointer "
3926 G_("return makes integer from pointer "
3928 return convert (type, rhs);
3930 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3931 return convert (type, rhs);
3936 case ic_argpass_nonproto:
3937 /* ??? This should not be an error when inlining calls to
3938 unprototyped functions. */
3939 error ("incompatible type for argument %d of %qE", parmnum, rname);
3942 error ("incompatible types in assignment");
3945 error ("incompatible types in initialization");
3948 error ("incompatible types in return");
3954 return error_mark_node;
3957 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3958 is used for error and waring reporting and indicates which argument
3959 is being processed. */
3962 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3966 /* If FN was prototyped, the value has been converted already
3967 in convert_arguments. */
3968 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3971 type = TREE_TYPE (parm);
3972 ret = convert_for_assignment (type, value,
3973 ic_argpass_nonproto, fn,
3975 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3976 && INTEGRAL_TYPE_P (type)
3977 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3978 ret = default_conversion (ret);
3982 /* If VALUE is a compound expr all of whose expressions are constant, then
3983 return its value. Otherwise, return error_mark_node.
3985 This is for handling COMPOUND_EXPRs as initializer elements
3986 which is allowed with a warning when -pedantic is specified. */
3989 valid_compound_expr_initializer (tree value, tree endtype)
3991 if (TREE_CODE (value) == COMPOUND_EXPR)
3993 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3995 return error_mark_node;
3996 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3999 else if (!initializer_constant_valid_p (value, endtype))
4000 return error_mark_node;
4005 /* Perform appropriate conversions on the initial value of a variable,
4006 store it in the declaration DECL,
4007 and print any error messages that are appropriate.
4008 If the init is invalid, store an ERROR_MARK. */
4011 store_init_value (tree decl, tree init)
4015 /* If variable's type was invalidly declared, just ignore it. */
4017 type = TREE_TYPE (decl);
4018 if (TREE_CODE (type) == ERROR_MARK)
4021 /* Digest the specified initializer into an expression. */
4023 value = digest_init (type, init, true, TREE_STATIC (decl));
4025 /* Store the expression if valid; else report error. */
4027 if (!in_system_header
4028 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4029 warning (OPT_Wtraditional, "traditional C rejects automatic "
4030 "aggregate initialization");
4032 DECL_INITIAL (decl) = value;
4034 /* ANSI wants warnings about out-of-range constant initializers. */
4035 STRIP_TYPE_NOPS (value);
4036 constant_expression_warning (value);
4038 /* Check if we need to set array size from compound literal size. */
4039 if (TREE_CODE (type) == ARRAY_TYPE
4040 && TYPE_DOMAIN (type) == 0
4041 && value != error_mark_node)
4043 tree inside_init = init;
4045 STRIP_TYPE_NOPS (inside_init);
4046 inside_init = fold (inside_init);
4048 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4050 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4052 if (TYPE_DOMAIN (TREE_TYPE (decl)))
4054 /* For int foo[] = (int [3]){1}; we need to set array size
4055 now since later on array initializer will be just the
4056 brace enclosed list of the compound literal. */
4057 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
4059 layout_decl (decl, 0);
4065 /* Methods for storing and printing names for error messages. */
4067 /* Implement a spelling stack that allows components of a name to be pushed
4068 and popped. Each element on the stack is this structure. */
4080 #define SPELLING_STRING 1
4081 #define SPELLING_MEMBER 2
4082 #define SPELLING_BOUNDS 3
4084 static struct spelling *spelling; /* Next stack element (unused). */
4085 static struct spelling *spelling_base; /* Spelling stack base. */
4086 static int spelling_size; /* Size of the spelling stack. */
4088 /* Macros to save and restore the spelling stack around push_... functions.
4089 Alternative to SAVE_SPELLING_STACK. */
4091 #define SPELLING_DEPTH() (spelling - spelling_base)
4092 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4094 /* Push an element on the spelling stack with type KIND and assign VALUE
4097 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4099 int depth = SPELLING_DEPTH (); \
4101 if (depth >= spelling_size) \
4103 spelling_size += 10; \
4104 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4106 RESTORE_SPELLING_DEPTH (depth); \
4109 spelling->kind = (KIND); \
4110 spelling->MEMBER = (VALUE); \
4114 /* Push STRING on the stack. Printed literally. */
4117 push_string (const char *string)
4119 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4122 /* Push a member name on the stack. Printed as '.' STRING. */
4125 push_member_name (tree decl)
4127 const char *const string
4128 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4129 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4132 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4135 push_array_bounds (int bounds)
4137 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4140 /* Compute the maximum size in bytes of the printed spelling. */
4143 spelling_length (void)
4148 for (p = spelling_base; p < spelling; p++)
4150 if (p->kind == SPELLING_BOUNDS)
4153 size += strlen (p->u.s) + 1;
4159 /* Print the spelling to BUFFER and return it. */
4162 print_spelling (char *buffer)
4167 for (p = spelling_base; p < spelling; p++)
4168 if (p->kind == SPELLING_BOUNDS)
4170 sprintf (d, "[%d]", p->u.i);
4176 if (p->kind == SPELLING_MEMBER)
4178 for (s = p->u.s; (*d = *s++); d++)
4185 /* Issue an error message for a bad initializer component.
4186 MSGID identifies the message.
4187 The component name is taken from the spelling stack. */
4190 error_init (const char *msgid)
4194 error ("%s", _(msgid));
4195 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4197 error ("(near initialization for %qs)", ofwhat);
4200 /* Issue a pedantic warning for a bad initializer component.
4201 MSGID identifies the message.
4202 The component name is taken from the spelling stack. */
4205 pedwarn_init (const char *msgid)
4209 pedwarn ("%s", _(msgid));
4210 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4212 pedwarn ("(near initialization for %qs)", ofwhat);
4215 /* Issue a warning for a bad initializer component.
4216 MSGID identifies the message.
4217 The component name is taken from the spelling stack. */
4220 warning_init (const char *msgid)
4224 warning (0, "%s", _(msgid));
4225 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4227 warning (0, "(near initialization for %qs)", ofwhat);
4230 /* If TYPE is an array type and EXPR is a parenthesized string
4231 constant, warn if pedantic that EXPR is being used to initialize an
4232 object of type TYPE. */
4235 maybe_warn_string_init (tree type, struct c_expr expr)
4238 && TREE_CODE (type) == ARRAY_TYPE
4239 && TREE_CODE (expr.value) == STRING_CST
4240 && expr.original_code != STRING_CST)
4241 pedwarn_init ("array initialized from parenthesized string constant");
4244 /* Digest the parser output INIT as an initializer for type TYPE.
4245 Return a C expression of type TYPE to represent the initial value.
4247 If INIT is a string constant, STRICT_STRING is true if it is
4248 unparenthesized or we should not warn here for it being parenthesized.
4249 For other types of INIT, STRICT_STRING is not used.
4251 REQUIRE_CONSTANT requests an error if non-constant initializers or
4252 elements are seen. */
4255 digest_init (tree type, tree init, bool strict_string, int require_constant)
4257 enum tree_code code = TREE_CODE (type);
4258 tree inside_init = init;
4260 if (type == error_mark_node
4261 || init == error_mark_node
4262 || TREE_TYPE (init) == error_mark_node)
4263 return error_mark_node;
4265 STRIP_TYPE_NOPS (inside_init);
4267 inside_init = fold (inside_init);
4269 /* Initialization of an array of chars from a string constant
4270 optionally enclosed in braces. */
4272 if (code == ARRAY_TYPE && inside_init
4273 && TREE_CODE (inside_init) == STRING_CST)
4275 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4276 /* Note that an array could be both an array of character type
4277 and an array of wchar_t if wchar_t is signed char or unsigned
4279 bool char_array = (typ1 == char_type_node
4280 || typ1 == signed_char_type_node
4281 || typ1 == unsigned_char_type_node);
4282 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4283 if (char_array || wchar_array)
4287 expr.value = inside_init;
4288 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4289 maybe_warn_string_init (type, expr);
4292 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4295 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4296 TYPE_MAIN_VARIANT (type)))
4299 if (!wchar_array && !char_string)
4301 error_init ("char-array initialized from wide string");
4302 return error_mark_node;
4304 if (char_string && !char_array)
4306 error_init ("wchar_t-array initialized from non-wide string");
4307 return error_mark_node;
4310 TREE_TYPE (inside_init) = type;
4311 if (TYPE_DOMAIN (type) != 0
4312 && TYPE_SIZE (type) != 0
4313 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4314 /* Subtract 1 (or sizeof (wchar_t))
4315 because it's ok to ignore the terminating null char
4316 that is counted in the length of the constant. */
4317 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4318 TREE_STRING_LENGTH (inside_init)
4319 - ((TYPE_PRECISION (typ1)
4320 != TYPE_PRECISION (char_type_node))
4321 ? (TYPE_PRECISION (wchar_type_node)
4324 pedwarn_init ("initializer-string for array of chars is too long");
4328 else if (INTEGRAL_TYPE_P (typ1))
4330 error_init ("array of inappropriate type initialized "
4331 "from string constant");
4332 return error_mark_node;
4336 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4337 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4338 below and handle as a constructor. */
4339 if (code == VECTOR_TYPE
4340 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4341 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4342 && TREE_CONSTANT (inside_init))
4344 if (TREE_CODE (inside_init) == VECTOR_CST
4345 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4346 TYPE_MAIN_VARIANT (type)))
4349 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4353 /* Iterate through elements and check if all constructor
4354 elements are *_CSTs. */
4355 for (link = CONSTRUCTOR_ELTS (inside_init);
4357 link = TREE_CHAIN (link))
4358 if (! CONSTANT_CLASS_P (TREE_VALUE (link)))
4362 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4366 /* Any type can be initialized
4367 from an expression of the same type, optionally with braces. */
4369 if (inside_init && TREE_TYPE (inside_init) != 0
4370 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4371 TYPE_MAIN_VARIANT (type))
4372 || (code == ARRAY_TYPE
4373 && comptypes (TREE_TYPE (inside_init), type))
4374 || (code == VECTOR_TYPE
4375 && comptypes (TREE_TYPE (inside_init), type))
4376 || (code == POINTER_TYPE
4377 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4378 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4379 TREE_TYPE (type)))))
4381 if (code == POINTER_TYPE)
4383 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4385 if (TREE_CODE (inside_init) == STRING_CST
4386 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4387 inside_init = array_to_pointer_conversion (inside_init);
4390 error_init ("invalid use of non-lvalue array");
4391 return error_mark_node;
4396 if (code == VECTOR_TYPE)
4397 /* Although the types are compatible, we may require a
4399 inside_init = convert (type, inside_init);
4401 if (require_constant && !flag_isoc99
4402 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4404 /* As an extension, allow initializing objects with static storage
4405 duration with compound literals (which are then treated just as
4406 the brace enclosed list they contain). */
4407 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4408 inside_init = DECL_INITIAL (decl);
4411 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4412 && TREE_CODE (inside_init) != CONSTRUCTOR)
4414 error_init ("array initialized from non-constant array expression");
4415 return error_mark_node;
4418 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4419 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4421 /* Compound expressions can only occur here if -pedantic or
4422 -pedantic-errors is specified. In the later case, we always want
4423 an error. In the former case, we simply want a warning. */
4424 if (require_constant && pedantic
4425 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4428 = valid_compound_expr_initializer (inside_init,
4429 TREE_TYPE (inside_init));
4430 if (inside_init == error_mark_node)
4431 error_init ("initializer element is not constant");
4433 pedwarn_init ("initializer element is not constant");
4434 if (flag_pedantic_errors)
4435 inside_init = error_mark_node;
4437 else if (require_constant
4438 && !initializer_constant_valid_p (inside_init,
4439 TREE_TYPE (inside_init)))
4441 error_init ("initializer element is not constant");
4442 inside_init = error_mark_node;
4445 /* Added to enable additional -Wmissing-format-attribute warnings. */
4446 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4447 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4452 /* Handle scalar types, including conversions. */
4454 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4455 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4456 || code == VECTOR_TYPE)
4458 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4459 && (TREE_CODE (init) == STRING_CST
4460 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4461 init = array_to_pointer_conversion (init);
4463 = convert_for_assignment (type, init, ic_init,
4464 NULL_TREE, NULL_TREE, 0);
4466 /* Check to see if we have already given an error message. */
4467 if (inside_init == error_mark_node)
4469 else if (require_constant && !TREE_CONSTANT (inside_init))
4471 error_init ("initializer element is not constant");
4472 inside_init = error_mark_node;
4474 else if (require_constant
4475 && !initializer_constant_valid_p (inside_init,
4476 TREE_TYPE (inside_init)))
4478 error_init ("initializer element is not computable at load time");
4479 inside_init = error_mark_node;
4485 /* Come here only for records and arrays. */
4487 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4489 error_init ("variable-sized object may not be initialized");
4490 return error_mark_node;
4493 error_init ("invalid initializer");
4494 return error_mark_node;
4497 /* Handle initializers that use braces. */
4499 /* Type of object we are accumulating a constructor for.
4500 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4501 static tree constructor_type;
4503 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4505 static tree constructor_fields;
4507 /* For an ARRAY_TYPE, this is the specified index
4508 at which to store the next element we get. */
4509 static tree constructor_index;
4511 /* For an ARRAY_TYPE, this is the maximum index. */
4512 static tree constructor_max_index;
4514 /* For a RECORD_TYPE, this is the first field not yet written out. */
4515 static tree constructor_unfilled_fields;
4517 /* For an ARRAY_TYPE, this is the index of the first element
4518 not yet written out. */
4519 static tree constructor_unfilled_index;
4521 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4522 This is so we can generate gaps between fields, when appropriate. */
4523 static tree constructor_bit_index;
4525 /* If we are saving up the elements rather than allocating them,
4526 this is the list of elements so far (in reverse order,
4527 most recent first). */
4528 static tree constructor_elements;
4530 /* 1 if constructor should be incrementally stored into a constructor chain,
4531 0 if all the elements should be kept in AVL tree. */
4532 static int constructor_incremental;
4534 /* 1 if so far this constructor's elements are all compile-time constants. */
4535 static int constructor_constant;
4537 /* 1 if so far this constructor's elements are all valid address constants. */
4538 static int constructor_simple;
4540 /* 1 if this constructor is erroneous so far. */
4541 static int constructor_erroneous;
4543 /* Structure for managing pending initializer elements, organized as an
4548 struct init_node *left, *right;
4549 struct init_node *parent;
4555 /* Tree of pending elements at this constructor level.
4556 These are elements encountered out of order
4557 which belong at places we haven't reached yet in actually
4559 Will never hold tree nodes across GC runs. */
4560 static struct init_node *constructor_pending_elts;
4562 /* The SPELLING_DEPTH of this constructor. */
4563 static int constructor_depth;
4565 /* DECL node for which an initializer is being read.
4566 0 means we are reading a constructor expression
4567 such as (struct foo) {...}. */
4568 static tree constructor_decl;
4570 /* Nonzero if this is an initializer for a top-level decl. */
4571 static int constructor_top_level;
4573 /* Nonzero if there were any member designators in this initializer. */
4574 static int constructor_designated;
4576 /* Nesting depth of designator list. */
4577 static int designator_depth;
4579 /* Nonzero if there were diagnosed errors in this designator list. */
4580 static int designator_errorneous;
4583 /* This stack has a level for each implicit or explicit level of
4584 structuring in the initializer, including the outermost one. It
4585 saves the values of most of the variables above. */
4587 struct constructor_range_stack;
4589 struct constructor_stack
4591 struct constructor_stack *next;
4596 tree unfilled_index;
4597 tree unfilled_fields;
4600 struct init_node *pending_elts;
4603 /* If value nonzero, this value should replace the entire
4604 constructor at this level. */
4605 struct c_expr replacement_value;
4606 struct constructor_range_stack *range_stack;
4616 static struct constructor_stack *constructor_stack;
4618 /* This stack represents designators from some range designator up to
4619 the last designator in the list. */
4621 struct constructor_range_stack
4623 struct constructor_range_stack *next, *prev;
4624 struct constructor_stack *stack;
4631 static struct constructor_range_stack *constructor_range_stack;
4633 /* This stack records separate initializers that are nested.
4634 Nested initializers can't happen in ANSI C, but GNU C allows them
4635 in cases like { ... (struct foo) { ... } ... }. */
4637 struct initializer_stack
4639 struct initializer_stack *next;
4641 struct constructor_stack *constructor_stack;
4642 struct constructor_range_stack *constructor_range_stack;
4644 struct spelling *spelling;
4645 struct spelling *spelling_base;
4648 char require_constant_value;
4649 char require_constant_elements;
4652 static struct initializer_stack *initializer_stack;
4654 /* Prepare to parse and output the initializer for variable DECL. */
4657 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4660 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4662 p->decl = constructor_decl;
4663 p->require_constant_value = require_constant_value;
4664 p->require_constant_elements = require_constant_elements;
4665 p->constructor_stack = constructor_stack;
4666 p->constructor_range_stack = constructor_range_stack;
4667 p->elements = constructor_elements;
4668 p->spelling = spelling;
4669 p->spelling_base = spelling_base;
4670 p->spelling_size = spelling_size;
4671 p->top_level = constructor_top_level;
4672 p->next = initializer_stack;
4673 initializer_stack = p;
4675 constructor_decl = decl;
4676 constructor_designated = 0;
4677 constructor_top_level = top_level;
4679 if (decl != 0 && decl != error_mark_node)
4681 require_constant_value = TREE_STATIC (decl);
4682 require_constant_elements
4683 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4684 /* For a scalar, you can always use any value to initialize,
4685 even within braces. */
4686 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4687 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4688 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4689 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4690 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4694 require_constant_value = 0;
4695 require_constant_elements = 0;
4696 locus = "(anonymous)";
4699 constructor_stack = 0;
4700 constructor_range_stack = 0;
4702 missing_braces_mentioned = 0;
4706 RESTORE_SPELLING_DEPTH (0);
4709 push_string (locus);
4715 struct initializer_stack *p = initializer_stack;
4717 /* Free the whole constructor stack of this initializer. */
4718 while (constructor_stack)
4720 struct constructor_stack *q = constructor_stack;
4721 constructor_stack = q->next;
4725 gcc_assert (!constructor_range_stack);
4727 /* Pop back to the data of the outer initializer (if any). */
4728 free (spelling_base);
4730 constructor_decl = p->decl;
4731 require_constant_value = p->require_constant_value;
4732 require_constant_elements = p->require_constant_elements;
4733 constructor_stack = p->constructor_stack;
4734 constructor_range_stack = p->constructor_range_stack;
4735 constructor_elements = p->elements;
4736 spelling = p->spelling;
4737 spelling_base = p->spelling_base;
4738 spelling_size = p->spelling_size;
4739 constructor_top_level = p->top_level;
4740 initializer_stack = p->next;
4744 /* Call here when we see the initializer is surrounded by braces.
4745 This is instead of a call to push_init_level;
4746 it is matched by a call to pop_init_level.
4748 TYPE is the type to initialize, for a constructor expression.
4749 For an initializer for a decl, TYPE is zero. */
4752 really_start_incremental_init (tree type)
4754 struct constructor_stack *p = XNEW (struct constructor_stack);
4757 type = TREE_TYPE (constructor_decl);
4759 if (targetm.vector_opaque_p (type))
4760 error ("opaque vector types cannot be initialized");
4762 p->type = constructor_type;
4763 p->fields = constructor_fields;
4764 p->index = constructor_index;
4765 p->max_index = constructor_max_index;
4766 p->unfilled_index = constructor_unfilled_index;
4767 p->unfilled_fields = constructor_unfilled_fields;
4768 p->bit_index = constructor_bit_index;
4769 p->elements = constructor_elements;
4770 p->constant = constructor_constant;
4771 p->simple = constructor_simple;
4772 p->erroneous = constructor_erroneous;
4773 p->pending_elts = constructor_pending_elts;
4774 p->depth = constructor_depth;
4775 p->replacement_value.value = 0;
4776 p->replacement_value.original_code = ERROR_MARK;
4780 p->incremental = constructor_incremental;
4781 p->designated = constructor_designated;
4783 constructor_stack = p;
4785 constructor_constant = 1;
4786 constructor_simple = 1;
4787 constructor_depth = SPELLING_DEPTH ();
4788 constructor_elements = 0;
4789 constructor_pending_elts = 0;
4790 constructor_type = type;
4791 constructor_incremental = 1;
4792 constructor_designated = 0;
4793 designator_depth = 0;
4794 designator_errorneous = 0;
4796 if (TREE_CODE (constructor_type) == RECORD_TYPE
4797 || TREE_CODE (constructor_type) == UNION_TYPE)
4799 constructor_fields = TYPE_FIELDS (constructor_type);
4800 /* Skip any nameless bit fields at the beginning. */
4801 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4802 && DECL_NAME (constructor_fields) == 0)
4803 constructor_fields = TREE_CHAIN (constructor_fields);
4805 constructor_unfilled_fields = constructor_fields;
4806 constructor_bit_index = bitsize_zero_node;
4808 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4810 if (TYPE_DOMAIN (constructor_type))
4812 constructor_max_index
4813 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4815 /* Detect non-empty initializations of zero-length arrays. */
4816 if (constructor_max_index == NULL_TREE
4817 && TYPE_SIZE (constructor_type))
4818 constructor_max_index = build_int_cst (NULL_TREE, -1);
4820 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4821 to initialize VLAs will cause a proper error; avoid tree
4822 checking errors as well by setting a safe value. */
4823 if (constructor_max_index
4824 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4825 constructor_max_index = build_int_cst (NULL_TREE, -1);
4828 = convert (bitsizetype,
4829 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4833 constructor_index = bitsize_zero_node;
4834 constructor_max_index = NULL_TREE;
4837 constructor_unfilled_index = constructor_index;
4839 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4841 /* Vectors are like simple fixed-size arrays. */
4842 constructor_max_index =
4843 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4844 constructor_index = convert (bitsizetype, bitsize_zero_node);
4845 constructor_unfilled_index = constructor_index;
4849 /* Handle the case of int x = {5}; */
4850 constructor_fields = constructor_type;
4851 constructor_unfilled_fields = constructor_type;
4855 /* Push down into a subobject, for initialization.
4856 If this is for an explicit set of braces, IMPLICIT is 0.
4857 If it is because the next element belongs at a lower level,
4858 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4861 push_init_level (int implicit)
4863 struct constructor_stack *p;
4864 tree value = NULL_TREE;
4866 /* If we've exhausted any levels that didn't have braces,
4867 pop them now. If implicit == 1, this will have been done in
4868 process_init_element; do not repeat it here because in the case
4869 of excess initializers for an empty aggregate this leads to an
4870 infinite cycle of popping a level and immediately recreating
4874 while (constructor_stack->implicit)
4876 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4877 || TREE_CODE (constructor_type) == UNION_TYPE)
4878 && constructor_fields == 0)
4879 process_init_element (pop_init_level (1));
4880 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4881 && constructor_max_index
4882 && tree_int_cst_lt (constructor_max_index,
4884 process_init_element (pop_init_level (1));
4890 /* Unless this is an explicit brace, we need to preserve previous
4894 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4895 || TREE_CODE (constructor_type) == UNION_TYPE)
4896 && constructor_fields)
4897 value = find_init_member (constructor_fields);
4898 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4899 value = find_init_member (constructor_index);
4902 p = XNEW (struct constructor_stack);
4903 p->type = constructor_type;
4904 p->fields = constructor_fields;
4905 p->index = constructor_index;
4906 p->max_index = constructor_max_index;
4907 p->unfilled_index = constructor_unfilled_index;
4908 p->unfilled_fields = constructor_unfilled_fields;
4909 p->bit_index = constructor_bit_index;
4910 p->elements = constructor_elements;
4911 p->constant = constructor_constant;
4912 p->simple = constructor_simple;
4913 p->erroneous = constructor_erroneous;
4914 p->pending_elts = constructor_pending_elts;
4915 p->depth = constructor_depth;
4916 p->replacement_value.value = 0;
4917 p->replacement_value.original_code = ERROR_MARK;
4918 p->implicit = implicit;
4920 p->incremental = constructor_incremental;
4921 p->designated = constructor_designated;
4922 p->next = constructor_stack;
4924 constructor_stack = p;
4926 constructor_constant = 1;
4927 constructor_simple = 1;
4928 constructor_depth = SPELLING_DEPTH ();
4929 constructor_elements = 0;
4930 constructor_incremental = 1;
4931 constructor_designated = 0;
4932 constructor_pending_elts = 0;
4935 p->range_stack = constructor_range_stack;
4936 constructor_range_stack = 0;
4937 designator_depth = 0;
4938 designator_errorneous = 0;
4941 /* Don't die if an entire brace-pair level is superfluous
4942 in the containing level. */
4943 if (constructor_type == 0)
4945 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4946 || TREE_CODE (constructor_type) == UNION_TYPE)
4948 /* Don't die if there are extra init elts at the end. */
4949 if (constructor_fields == 0)
4950 constructor_type = 0;
4953 constructor_type = TREE_TYPE (constructor_fields);
4954 push_member_name (constructor_fields);
4955 constructor_depth++;
4958 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4960 constructor_type = TREE_TYPE (constructor_type);
4961 push_array_bounds (tree_low_cst (constructor_index, 0));
4962 constructor_depth++;
4965 if (constructor_type == 0)
4967 error_init ("extra brace group at end of initializer");
4968 constructor_fields = 0;
4969 constructor_unfilled_fields = 0;
4973 if (value && TREE_CODE (value) == CONSTRUCTOR)
4975 constructor_constant = TREE_CONSTANT (value);
4976 constructor_simple = TREE_STATIC (value);
4977 constructor_elements = CONSTRUCTOR_ELTS (value);
4978 if (constructor_elements
4979 && (TREE_CODE (constructor_type) == RECORD_TYPE
4980 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4981 set_nonincremental_init ();
4984 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4986 missing_braces_mentioned = 1;
4987 warning_init ("missing braces around initializer");
4990 if (TREE_CODE (constructor_type) == RECORD_TYPE
4991 || TREE_CODE (constructor_type) == UNION_TYPE)
4993 constructor_fields = TYPE_FIELDS (constructor_type);
4994 /* Skip any nameless bit fields at the beginning. */
4995 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4996 && DECL_NAME (constructor_fields) == 0)
4997 constructor_fields = TREE_CHAIN (constructor_fields);
4999 constructor_unfilled_fields = constructor_fields;
5000 constructor_bit_index = bitsize_zero_node;
5002 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5004 /* Vectors are like simple fixed-size arrays. */
5005 constructor_max_index =
5006 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5007 constructor_index = convert (bitsizetype, integer_zero_node);
5008 constructor_unfilled_index = constructor_index;
5010 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5012 if (TYPE_DOMAIN (constructor_type))
5014 constructor_max_index
5015 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5017 /* Detect non-empty initializations of zero-length arrays. */
5018 if (constructor_max_index == NULL_TREE
5019 && TYPE_SIZE (constructor_type))
5020 constructor_max_index = build_int_cst (NULL_TREE, -1);
5022 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5023 to initialize VLAs will cause a proper error; avoid tree
5024 checking errors as well by setting a safe value. */
5025 if (constructor_max_index
5026 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5027 constructor_max_index = build_int_cst (NULL_TREE, -1);
5030 = convert (bitsizetype,
5031 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5034 constructor_index = bitsize_zero_node;
5036 constructor_unfilled_index = constructor_index;
5037 if (value && TREE_CODE (value) == STRING_CST)
5039 /* We need to split the char/wchar array into individual
5040 characters, so that we don't have to special case it
5042 set_nonincremental_init_from_string (value);
5047 if (constructor_type != error_mark_node)
5048 warning_init ("braces around scalar initializer");
5049 constructor_fields = constructor_type;
5050 constructor_unfilled_fields = constructor_type;
5054 /* At the end of an implicit or explicit brace level,
5055 finish up that level of constructor. If a single expression
5056 with redundant braces initialized that level, return the
5057 c_expr structure for that expression. Otherwise, the original_code
5058 element is set to ERROR_MARK.
5059 If we were outputting the elements as they are read, return 0 as the value
5060 from inner levels (process_init_element ignores that),
5061 but return error_mark_node as the value from the outermost level
5062 (that's what we want to put in DECL_INITIAL).
5063 Otherwise, return a CONSTRUCTOR expression as the value. */
5066 pop_init_level (int implicit)
5068 struct constructor_stack *p;
5071 ret.original_code = ERROR_MARK;
5075 /* When we come to an explicit close brace,
5076 pop any inner levels that didn't have explicit braces. */
5077 while (constructor_stack->implicit)
5078 process_init_element (pop_init_level (1));
5080 gcc_assert (!constructor_range_stack);
5083 /* Now output all pending elements. */
5084 constructor_incremental = 1;
5085 output_pending_init_elements (1);
5087 p = constructor_stack;
5089 /* Error for initializing a flexible array member, or a zero-length
5090 array member in an inappropriate context. */
5091 if (constructor_type && constructor_fields
5092 && TREE_CODE (constructor_type) == ARRAY_TYPE
5093 && TYPE_DOMAIN (constructor_type)
5094 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5096 /* Silently discard empty initializations. The parser will
5097 already have pedwarned for empty brackets. */
5098 if (integer_zerop (constructor_unfilled_index))
5099 constructor_type = NULL_TREE;
5102 gcc_assert (!TYPE_SIZE (constructor_type));
5104 if (constructor_depth > 2)
5105 error_init ("initialization of flexible array member in a nested context");
5107 pedwarn_init ("initialization of a flexible array member");
5109 /* We have already issued an error message for the existence
5110 of a flexible array member not at the end of the structure.
5111 Discard the initializer so that we do not die later. */
5112 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5113 constructor_type = NULL_TREE;
5117 /* Warn when some struct elements are implicitly initialized to zero. */
5118 if (warn_missing_field_initializers
5120 && TREE_CODE (constructor_type) == RECORD_TYPE
5121 && constructor_unfilled_fields)
5123 /* Do not warn for flexible array members or zero-length arrays. */
5124 while (constructor_unfilled_fields
5125 && (!DECL_SIZE (constructor_unfilled_fields)
5126 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5127 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5129 /* Do not warn if this level of the initializer uses member
5130 designators; it is likely to be deliberate. */
5131 if (constructor_unfilled_fields && !constructor_designated)
5133 push_member_name (constructor_unfilled_fields);
5134 warning_init ("missing initializer");
5135 RESTORE_SPELLING_DEPTH (constructor_depth);
5139 /* Pad out the end of the structure. */
5140 if (p->replacement_value.value)
5141 /* If this closes a superfluous brace pair,
5142 just pass out the element between them. */
5143 ret = p->replacement_value;
5144 else if (constructor_type == 0)
5146 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5147 && TREE_CODE (constructor_type) != UNION_TYPE
5148 && TREE_CODE (constructor_type) != ARRAY_TYPE
5149 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5151 /* A nonincremental scalar initializer--just return
5152 the element, after verifying there is just one. */
5153 if (constructor_elements == 0)
5155 if (!constructor_erroneous)
5156 error_init ("empty scalar initializer");
5157 ret.value = error_mark_node;
5159 else if (TREE_CHAIN (constructor_elements) != 0)
5161 error_init ("extra elements in scalar initializer");
5162 ret.value = TREE_VALUE (constructor_elements);
5165 ret.value = TREE_VALUE (constructor_elements);
5169 if (constructor_erroneous)
5170 ret.value = error_mark_node;
5173 ret.value = build_constructor (constructor_type,
5174 nreverse (constructor_elements));
5175 if (constructor_constant)
5176 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5177 if (constructor_constant && constructor_simple)
5178 TREE_STATIC (ret.value) = 1;
5182 constructor_type = p->type;
5183 constructor_fields = p->fields;
5184 constructor_index = p->index;
5185 constructor_max_index = p->max_index;
5186 constructor_unfilled_index = p->unfilled_index;
5187 constructor_unfilled_fields = p->unfilled_fields;
5188 constructor_bit_index = p->bit_index;
5189 constructor_elements = p->elements;
5190 constructor_constant = p->constant;
5191 constructor_simple = p->simple;
5192 constructor_erroneous = p->erroneous;
5193 constructor_incremental = p->incremental;
5194 constructor_designated = p->designated;
5195 constructor_pending_elts = p->pending_elts;
5196 constructor_depth = p->depth;
5198 constructor_range_stack = p->range_stack;
5199 RESTORE_SPELLING_DEPTH (constructor_depth);
5201 constructor_stack = p->next;
5206 if (constructor_stack == 0)
5208 ret.value = error_mark_node;
5216 /* Common handling for both array range and field name designators.
5217 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5220 set_designator (int array)
5223 enum tree_code subcode;
5225 /* Don't die if an entire brace-pair level is superfluous
5226 in the containing level. */
5227 if (constructor_type == 0)
5230 /* If there were errors in this designator list already, bail out
5232 if (designator_errorneous)
5235 if (!designator_depth)
5237 gcc_assert (!constructor_range_stack);
5239 /* Designator list starts at the level of closest explicit
5241 while (constructor_stack->implicit)
5242 process_init_element (pop_init_level (1));
5243 constructor_designated = 1;
5247 switch (TREE_CODE (constructor_type))
5251 subtype = TREE_TYPE (constructor_fields);
5252 if (subtype != error_mark_node)
5253 subtype = TYPE_MAIN_VARIANT (subtype);
5256 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5262 subcode = TREE_CODE (subtype);
5263 if (array && subcode != ARRAY_TYPE)
5265 error_init ("array index in non-array initializer");
5268 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5270 error_init ("field name not in record or union initializer");
5274 constructor_designated = 1;
5275 push_init_level (2);
5279 /* If there are range designators in designator list, push a new designator
5280 to constructor_range_stack. RANGE_END is end of such stack range or
5281 NULL_TREE if there is no range designator at this level. */
5284 push_range_stack (tree range_end)
5286 struct constructor_range_stack *p;
5288 p = GGC_NEW (struct constructor_range_stack);
5289 p->prev = constructor_range_stack;
5291 p->fields = constructor_fields;
5292 p->range_start = constructor_index;
5293 p->index = constructor_index;
5294 p->stack = constructor_stack;
5295 p->range_end = range_end;
5296 if (constructor_range_stack)
5297 constructor_range_stack->next = p;
5298 constructor_range_stack = p;
5301 /* Within an array initializer, specify the next index to be initialized.
5302 FIRST is that index. If LAST is nonzero, then initialize a range
5303 of indices, running from FIRST through LAST. */
5306 set_init_index (tree first, tree last)
5308 if (set_designator (1))
5311 designator_errorneous = 1;
5313 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5314 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5316 error_init ("array index in initializer not of integer type");
5320 if (TREE_CODE (first) != INTEGER_CST)
5321 error_init ("nonconstant array index in initializer");
5322 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5323 error_init ("nonconstant array index in initializer");
5324 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5325 error_init ("array index in non-array initializer");
5326 else if (tree_int_cst_sgn (first) == -1)
5327 error_init ("array index in initializer exceeds array bounds");
5328 else if (constructor_max_index
5329 && tree_int_cst_lt (constructor_max_index, first))
5330 error_init ("array index in initializer exceeds array bounds");
5333 constructor_index = convert (bitsizetype, first);
5337 if (tree_int_cst_equal (first, last))
5339 else if (tree_int_cst_lt (last, first))
5341 error_init ("empty index range in initializer");
5346 last = convert (bitsizetype, last);
5347 if (constructor_max_index != 0
5348 && tree_int_cst_lt (constructor_max_index, last))
5350 error_init ("array index range in initializer exceeds array bounds");
5357 designator_errorneous = 0;
5358 if (constructor_range_stack || last)
5359 push_range_stack (last);
5363 /* Within a struct initializer, specify the next field to be initialized. */
5366 set_init_label (tree fieldname)
5370 if (set_designator (0))
5373 designator_errorneous = 1;
5375 if (TREE_CODE (constructor_type) != RECORD_TYPE
5376 && TREE_CODE (constructor_type) != UNION_TYPE)
5378 error_init ("field name not in record or union initializer");
5382 for (tail = TYPE_FIELDS (constructor_type); tail;
5383 tail = TREE_CHAIN (tail))
5385 if (DECL_NAME (tail) == fieldname)
5390 error ("unknown field %qE specified in initializer", fieldname);
5393 constructor_fields = tail;
5395 designator_errorneous = 0;
5396 if (constructor_range_stack)
5397 push_range_stack (NULL_TREE);
5401 /* Add a new initializer to the tree of pending initializers. PURPOSE
5402 identifies the initializer, either array index or field in a structure.
5403 VALUE is the value of that index or field. */
5406 add_pending_init (tree purpose, tree value)
5408 struct init_node *p, **q, *r;
5410 q = &constructor_pending_elts;
5413 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5418 if (tree_int_cst_lt (purpose, p->purpose))
5420 else if (tree_int_cst_lt (p->purpose, purpose))
5424 if (TREE_SIDE_EFFECTS (p->value))
5425 warning_init ("initialized field with side-effects overwritten");
5435 bitpos = bit_position (purpose);
5439 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5441 else if (p->purpose != purpose)
5445 if (TREE_SIDE_EFFECTS (p->value))
5446 warning_init ("initialized field with side-effects overwritten");
5453 r = GGC_NEW (struct init_node);
5454 r->purpose = purpose;
5465 struct init_node *s;
5469 if (p->balance == 0)
5471 else if (p->balance < 0)
5478 p->left->parent = p;
5495 constructor_pending_elts = r;
5500 struct init_node *t = r->right;
5504 r->right->parent = r;
5509 p->left->parent = p;
5512 p->balance = t->balance < 0;
5513 r->balance = -(t->balance > 0);
5528 constructor_pending_elts = t;
5534 /* p->balance == +1; growth of left side balances the node. */
5539 else /* r == p->right */
5541 if (p->balance == 0)
5542 /* Growth propagation from right side. */
5544 else if (p->balance > 0)
5551 p->right->parent = p;
5568 constructor_pending_elts = r;
5570 else /* r->balance == -1 */
5573 struct init_node *t = r->left;
5577 r->left->parent = r;
5582 p->right->parent = p;
5585 r->balance = (t->balance < 0);
5586 p->balance = -(t->balance > 0);
5601 constructor_pending_elts = t;
5607 /* p->balance == -1; growth of right side balances the node. */
5618 /* Build AVL tree from a sorted chain. */
5621 set_nonincremental_init (void)
5625 if (TREE_CODE (constructor_type) != RECORD_TYPE
5626 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5629 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5630 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5631 constructor_elements = 0;
5632 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5634 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5635 /* Skip any nameless bit fields at the beginning. */
5636 while (constructor_unfilled_fields != 0
5637 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5638 && DECL_NAME (constructor_unfilled_fields) == 0)
5639 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5642 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5644 if (TYPE_DOMAIN (constructor_type))
5645 constructor_unfilled_index
5646 = convert (bitsizetype,
5647 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5649 constructor_unfilled_index = bitsize_zero_node;
5651 constructor_incremental = 0;
5654 /* Build AVL tree from a string constant. */
5657 set_nonincremental_init_from_string (tree str)
5659 tree value, purpose, type;
5660 HOST_WIDE_INT val[2];
5661 const char *p, *end;
5662 int byte, wchar_bytes, charwidth, bitpos;
5664 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5666 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5667 == TYPE_PRECISION (char_type_node))
5671 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5672 == TYPE_PRECISION (wchar_type_node));
5673 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5675 charwidth = TYPE_PRECISION (char_type_node);
5676 type = TREE_TYPE (constructor_type);
5677 p = TREE_STRING_POINTER (str);
5678 end = p + TREE_STRING_LENGTH (str);
5680 for (purpose = bitsize_zero_node;
5681 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5682 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5684 if (wchar_bytes == 1)
5686 val[1] = (unsigned char) *p++;
5693 for (byte = 0; byte < wchar_bytes; byte++)
5695 if (BYTES_BIG_ENDIAN)
5696 bitpos = (wchar_bytes - byte - 1) * charwidth;
5698 bitpos = byte * charwidth;
5699 val[bitpos < HOST_BITS_PER_WIDE_INT]
5700 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5701 << (bitpos % HOST_BITS_PER_WIDE_INT);
5705 if (!TYPE_UNSIGNED (type))
5707 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5708 if (bitpos < HOST_BITS_PER_WIDE_INT)
5710 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5712 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5716 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5721 else if (val[0] & (((HOST_WIDE_INT) 1)
5722 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5723 val[0] |= ((HOST_WIDE_INT) -1)
5724 << (bitpos - HOST_BITS_PER_WIDE_INT);
5727 value = build_int_cst_wide (type, val[1], val[0]);
5728 add_pending_init (purpose, value);
5731 constructor_incremental = 0;
5734 /* Return value of FIELD in pending initializer or zero if the field was
5735 not initialized yet. */
5738 find_init_member (tree field)
5740 struct init_node *p;
5742 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5744 if (constructor_incremental
5745 && tree_int_cst_lt (field, constructor_unfilled_index))
5746 set_nonincremental_init ();
5748 p = constructor_pending_elts;
5751 if (tree_int_cst_lt (field, p->purpose))
5753 else if (tree_int_cst_lt (p->purpose, field))
5759 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5761 tree bitpos = bit_position (field);
5763 if (constructor_incremental
5764 && (!constructor_unfilled_fields
5765 || tree_int_cst_lt (bitpos,
5766 bit_position (constructor_unfilled_fields))))
5767 set_nonincremental_init ();
5769 p = constructor_pending_elts;
5772 if (field == p->purpose)
5774 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5780 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5782 if (constructor_elements
5783 && TREE_PURPOSE (constructor_elements) == field)
5784 return TREE_VALUE (constructor_elements);
5789 /* "Output" the next constructor element.
5790 At top level, really output it to assembler code now.
5791 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5792 TYPE is the data type that the containing data type wants here.
5793 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5794 If VALUE is a string constant, STRICT_STRING is true if it is
5795 unparenthesized or we should not warn here for it being parenthesized.
5796 For other types of VALUE, STRICT_STRING is not used.
5798 PENDING if non-nil means output pending elements that belong
5799 right after this element. (PENDING is normally 1;
5800 it is 0 while outputting pending elements, to avoid recursion.) */
5803 output_init_element (tree value, bool strict_string, tree type, tree field,
5806 if (type == error_mark_node || value == error_mark_node)
5808 constructor_erroneous = 1;
5811 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5812 && (TREE_CODE (value) == STRING_CST
5813 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
5814 && !(TREE_CODE (value) == STRING_CST
5815 && TREE_CODE (type) == ARRAY_TYPE
5816 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5817 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5818 TYPE_MAIN_VARIANT (type)))
5819 value = array_to_pointer_conversion (value);
5821 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5822 && require_constant_value && !flag_isoc99 && pending)
5824 /* As an extension, allow initializing objects with static storage
5825 duration with compound literals (which are then treated just as
5826 the brace enclosed list they contain). */
5827 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5828 value = DECL_INITIAL (decl);
5831 if (value == error_mark_node)
5832 constructor_erroneous = 1;
5833 else if (!TREE_CONSTANT (value))
5834 constructor_constant = 0;
5835 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5836 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5837 || TREE_CODE (constructor_type) == UNION_TYPE)
5838 && DECL_C_BIT_FIELD (field)
5839 && TREE_CODE (value) != INTEGER_CST))
5840 constructor_simple = 0;
5842 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5844 if (require_constant_value)
5846 error_init ("initializer element is not constant");
5847 value = error_mark_node;
5849 else if (require_constant_elements)
5850 pedwarn ("initializer element is not computable at load time");
5853 /* If this field is empty (and not at the end of structure),
5854 don't do anything other than checking the initializer. */
5856 && (TREE_TYPE (field) == error_mark_node
5857 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5858 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5859 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5860 || TREE_CHAIN (field)))))
5863 value = digest_init (type, value, strict_string, require_constant_value);
5864 if (value == error_mark_node)
5866 constructor_erroneous = 1;
5870 /* If this element doesn't come next in sequence,
5871 put it on constructor_pending_elts. */
5872 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5873 && (!constructor_incremental
5874 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5876 if (constructor_incremental
5877 && tree_int_cst_lt (field, constructor_unfilled_index))
5878 set_nonincremental_init ();
5880 add_pending_init (field, value);
5883 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5884 && (!constructor_incremental
5885 || field != constructor_unfilled_fields))
5887 /* We do this for records but not for unions. In a union,
5888 no matter which field is specified, it can be initialized
5889 right away since it starts at the beginning of the union. */
5890 if (constructor_incremental)
5892 if (!constructor_unfilled_fields)
5893 set_nonincremental_init ();
5896 tree bitpos, unfillpos;
5898 bitpos = bit_position (field);
5899 unfillpos = bit_position (constructor_unfilled_fields);
5901 if (tree_int_cst_lt (bitpos, unfillpos))
5902 set_nonincremental_init ();
5906 add_pending_init (field, value);
5909 else if (TREE_CODE (constructor_type) == UNION_TYPE
5910 && constructor_elements)
5912 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5913 warning_init ("initialized field with side-effects overwritten");
5915 /* We can have just one union field set. */
5916 constructor_elements = 0;
5919 /* Otherwise, output this element either to
5920 constructor_elements or to the assembler file. */
5922 if (field && TREE_CODE (field) == INTEGER_CST)
5923 field = copy_node (field);
5924 constructor_elements
5925 = tree_cons (field, value, constructor_elements);
5927 /* Advance the variable that indicates sequential elements output. */
5928 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5929 constructor_unfilled_index
5930 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5932 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5934 constructor_unfilled_fields
5935 = TREE_CHAIN (constructor_unfilled_fields);
5937 /* Skip any nameless bit fields. */
5938 while (constructor_unfilled_fields != 0
5939 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5940 && DECL_NAME (constructor_unfilled_fields) == 0)
5941 constructor_unfilled_fields =
5942 TREE_CHAIN (constructor_unfilled_fields);
5944 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5945 constructor_unfilled_fields = 0;
5947 /* Now output any pending elements which have become next. */
5949 output_pending_init_elements (0);
5952 /* Output any pending elements which have become next.
5953 As we output elements, constructor_unfilled_{fields,index}
5954 advances, which may cause other elements to become next;
5955 if so, they too are output.
5957 If ALL is 0, we return when there are
5958 no more pending elements to output now.
5960 If ALL is 1, we output space as necessary so that
5961 we can output all the pending elements. */
5964 output_pending_init_elements (int all)
5966 struct init_node *elt = constructor_pending_elts;
5971 /* Look through the whole pending tree.
5972 If we find an element that should be output now,
5973 output it. Otherwise, set NEXT to the element
5974 that comes first among those still pending. */
5979 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5981 if (tree_int_cst_equal (elt->purpose,
5982 constructor_unfilled_index))
5983 output_init_element (elt->value, true,
5984 TREE_TYPE (constructor_type),
5985 constructor_unfilled_index, 0);
5986 else if (tree_int_cst_lt (constructor_unfilled_index,
5989 /* Advance to the next smaller node. */
5994 /* We have reached the smallest node bigger than the
5995 current unfilled index. Fill the space first. */
5996 next = elt->purpose;
6002 /* Advance to the next bigger node. */
6007 /* We have reached the biggest node in a subtree. Find
6008 the parent of it, which is the next bigger node. */
6009 while (elt->parent && elt->parent->right == elt)
6012 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6015 next = elt->purpose;
6021 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6022 || TREE_CODE (constructor_type) == UNION_TYPE)
6024 tree ctor_unfilled_bitpos, elt_bitpos;
6026 /* If the current record is complete we are done. */
6027 if (constructor_unfilled_fields == 0)
6030 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6031 elt_bitpos = bit_position (elt->purpose);
6032 /* We can't compare fields here because there might be empty
6033 fields in between. */
6034 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6036 constructor_unfilled_fields = elt->purpose;
6037 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6040 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6042 /* Advance to the next smaller node. */
6047 /* We have reached the smallest node bigger than the
6048 current unfilled field. Fill the space first. */
6049 next = elt->purpose;
6055 /* Advance to the next bigger node. */
6060 /* We have reached the biggest node in a subtree. Find
6061 the parent of it, which is the next bigger node. */
6062 while (elt->parent && elt->parent->right == elt)
6066 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6067 bit_position (elt->purpose))))
6069 next = elt->purpose;
6077 /* Ordinarily return, but not if we want to output all
6078 and there are elements left. */
6079 if (!(all && next != 0))
6082 /* If it's not incremental, just skip over the gap, so that after
6083 jumping to retry we will output the next successive element. */
6084 if (TREE_CODE (constructor_type) == RECORD_TYPE
6085 || TREE_CODE (constructor_type) == UNION_TYPE)
6086 constructor_unfilled_fields = next;
6087 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6088 constructor_unfilled_index = next;
6090 /* ELT now points to the node in the pending tree with the next
6091 initializer to output. */
6095 /* Add one non-braced element to the current constructor level.
6096 This adjusts the current position within the constructor's type.
6097 This may also start or terminate implicit levels
6098 to handle a partly-braced initializer.
6100 Once this has found the correct level for the new element,
6101 it calls output_init_element. */
6104 process_init_element (struct c_expr value)
6106 tree orig_value = value.value;
6107 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6108 bool strict_string = value.original_code == STRING_CST;
6110 designator_depth = 0;
6111 designator_errorneous = 0;
6113 /* Handle superfluous braces around string cst as in
6114 char x[] = {"foo"}; */
6117 && TREE_CODE (constructor_type) == ARRAY_TYPE
6118 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6119 && integer_zerop (constructor_unfilled_index))
6121 if (constructor_stack->replacement_value.value)
6122 error_init ("excess elements in char array initializer");
6123 constructor_stack->replacement_value = value;
6127 if (constructor_stack->replacement_value.value != 0)
6129 error_init ("excess elements in struct initializer");
6133 /* Ignore elements of a brace group if it is entirely superfluous
6134 and has already been diagnosed. */
6135 if (constructor_type == 0)
6138 /* If we've exhausted any levels that didn't have braces,
6140 while (constructor_stack->implicit)
6142 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6143 || TREE_CODE (constructor_type) == UNION_TYPE)
6144 && constructor_fields == 0)
6145 process_init_element (pop_init_level (1));
6146 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6147 && (constructor_max_index == 0
6148 || tree_int_cst_lt (constructor_max_index,
6149 constructor_index)))
6150 process_init_element (pop_init_level (1));
6155 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6156 if (constructor_range_stack)
6158 /* If value is a compound literal and we'll be just using its
6159 content, don't put it into a SAVE_EXPR. */
6160 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6161 || !require_constant_value
6163 value.value = save_expr (value.value);
6168 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6171 enum tree_code fieldcode;
6173 if (constructor_fields == 0)
6175 pedwarn_init ("excess elements in struct initializer");
6179 fieldtype = TREE_TYPE (constructor_fields);
6180 if (fieldtype != error_mark_node)
6181 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6182 fieldcode = TREE_CODE (fieldtype);
6184 /* Error for non-static initialization of a flexible array member. */
6185 if (fieldcode == ARRAY_TYPE
6186 && !require_constant_value
6187 && TYPE_SIZE (fieldtype) == NULL_TREE
6188 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6190 error_init ("non-static initialization of a flexible array member");
6194 /* Accept a string constant to initialize a subarray. */
6195 if (value.value != 0
6196 && fieldcode == ARRAY_TYPE
6197 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6199 value.value = orig_value;
6200 /* Otherwise, if we have come to a subaggregate,
6201 and we don't have an element of its type, push into it. */
6202 else if (value.value != 0
6203 && value.value != error_mark_node
6204 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6205 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6206 || fieldcode == UNION_TYPE))
6208 push_init_level (1);
6214 push_member_name (constructor_fields);
6215 output_init_element (value.value, strict_string,
6216 fieldtype, constructor_fields, 1);
6217 RESTORE_SPELLING_DEPTH (constructor_depth);
6220 /* Do the bookkeeping for an element that was
6221 directly output as a constructor. */
6223 /* For a record, keep track of end position of last field. */
6224 if (DECL_SIZE (constructor_fields))
6225 constructor_bit_index
6226 = size_binop (PLUS_EXPR,
6227 bit_position (constructor_fields),
6228 DECL_SIZE (constructor_fields));
6230 /* If the current field was the first one not yet written out,
6231 it isn't now, so update. */
6232 if (constructor_unfilled_fields == constructor_fields)
6234 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6235 /* Skip any nameless bit fields. */
6236 while (constructor_unfilled_fields != 0
6237 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6238 && DECL_NAME (constructor_unfilled_fields) == 0)
6239 constructor_unfilled_fields =
6240 TREE_CHAIN (constructor_unfilled_fields);
6244 constructor_fields = TREE_CHAIN (constructor_fields);
6245 /* Skip any nameless bit fields at the beginning. */
6246 while (constructor_fields != 0
6247 && DECL_C_BIT_FIELD (constructor_fields)
6248 && DECL_NAME (constructor_fields) == 0)
6249 constructor_fields = TREE_CHAIN (constructor_fields);
6251 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6254 enum tree_code fieldcode;
6256 if (constructor_fields == 0)
6258 pedwarn_init ("excess elements in union initializer");
6262 fieldtype = TREE_TYPE (constructor_fields);
6263 if (fieldtype != error_mark_node)
6264 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6265 fieldcode = TREE_CODE (fieldtype);
6267 /* Warn that traditional C rejects initialization of unions.
6268 We skip the warning if the value is zero. This is done
6269 under the assumption that the zero initializer in user
6270 code appears conditioned on e.g. __STDC__ to avoid
6271 "missing initializer" warnings and relies on default
6272 initialization to zero in the traditional C case.
6273 We also skip the warning if the initializer is designated,
6274 again on the assumption that this must be conditional on
6275 __STDC__ anyway (and we've already complained about the
6276 member-designator already). */
6277 if (!in_system_header && !constructor_designated
6278 && !(value.value && (integer_zerop (value.value)
6279 || real_zerop (value.value))))
6280 warning (OPT_Wtraditional, "traditional C rejects initialization "
6283 /* Accept a string constant to initialize a subarray. */
6284 if (value.value != 0
6285 && fieldcode == ARRAY_TYPE
6286 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6288 value.value = orig_value;
6289 /* Otherwise, if we have come to a subaggregate,
6290 and we don't have an element of its type, push into it. */
6291 else if (value.value != 0
6292 && value.value != error_mark_node
6293 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6294 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6295 || fieldcode == UNION_TYPE))
6297 push_init_level (1);
6303 push_member_name (constructor_fields);
6304 output_init_element (value.value, strict_string,
6305 fieldtype, constructor_fields, 1);
6306 RESTORE_SPELLING_DEPTH (constructor_depth);
6309 /* Do the bookkeeping for an element that was
6310 directly output as a constructor. */
6312 constructor_bit_index = DECL_SIZE (constructor_fields);
6313 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6316 constructor_fields = 0;
6318 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6320 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6321 enum tree_code eltcode = TREE_CODE (elttype);
6323 /* Accept a string constant to initialize a subarray. */
6324 if (value.value != 0
6325 && eltcode == ARRAY_TYPE
6326 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6328 value.value = orig_value;
6329 /* Otherwise, if we have come to a subaggregate,
6330 and we don't have an element of its type, push into it. */
6331 else if (value.value != 0
6332 && value.value != error_mark_node
6333 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6334 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6335 || eltcode == UNION_TYPE))
6337 push_init_level (1);
6341 if (constructor_max_index != 0
6342 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6343 || integer_all_onesp (constructor_max_index)))
6345 pedwarn_init ("excess elements in array initializer");
6349 /* Now output the actual element. */
6352 push_array_bounds (tree_low_cst (constructor_index, 0));
6353 output_init_element (value.value, strict_string,
6354 elttype, constructor_index, 1);
6355 RESTORE_SPELLING_DEPTH (constructor_depth);
6359 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6362 /* If we are doing the bookkeeping for an element that was
6363 directly output as a constructor, we must update
6364 constructor_unfilled_index. */
6365 constructor_unfilled_index = constructor_index;
6367 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6369 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6371 /* Do a basic check of initializer size. Note that vectors
6372 always have a fixed size derived from their type. */
6373 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6375 pedwarn_init ("excess elements in vector initializer");
6379 /* Now output the actual element. */
6381 output_init_element (value.value, strict_string,
6382 elttype, constructor_index, 1);
6385 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6388 /* If we are doing the bookkeeping for an element that was
6389 directly output as a constructor, we must update
6390 constructor_unfilled_index. */
6391 constructor_unfilled_index = constructor_index;
6394 /* Handle the sole element allowed in a braced initializer
6395 for a scalar variable. */
6396 else if (constructor_type != error_mark_node
6397 && constructor_fields == 0)
6399 pedwarn_init ("excess elements in scalar initializer");
6405 output_init_element (value.value, strict_string,
6406 constructor_type, NULL_TREE, 1);
6407 constructor_fields = 0;
6410 /* Handle range initializers either at this level or anywhere higher
6411 in the designator stack. */
6412 if (constructor_range_stack)
6414 struct constructor_range_stack *p, *range_stack;
6417 range_stack = constructor_range_stack;
6418 constructor_range_stack = 0;
6419 while (constructor_stack != range_stack->stack)
6421 gcc_assert (constructor_stack->implicit);
6422 process_init_element (pop_init_level (1));
6424 for (p = range_stack;
6425 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6428 gcc_assert (constructor_stack->implicit);
6429 process_init_element (pop_init_level (1));
6432 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6433 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6438 constructor_index = p->index;
6439 constructor_fields = p->fields;
6440 if (finish && p->range_end && p->index == p->range_start)
6448 push_init_level (2);
6449 p->stack = constructor_stack;
6450 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6451 p->index = p->range_start;
6455 constructor_range_stack = range_stack;
6462 constructor_range_stack = 0;
6465 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6466 (guaranteed to be 'volatile' or null) and ARGS (represented using
6467 an ASM_EXPR node). */
6469 build_asm_stmt (tree cv_qualifier, tree args)
6471 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6472 ASM_VOLATILE_P (args) = 1;
6473 return add_stmt (args);
6476 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6477 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6478 SIMPLE indicates whether there was anything at all after the
6479 string in the asm expression -- asm("blah") and asm("blah" : )
6480 are subtly different. We use a ASM_EXPR node to represent this. */
6482 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6488 const char *constraint;
6489 const char **oconstraints;
6490 bool allows_mem, allows_reg, is_inout;
6491 int ninputs, noutputs;
6493 ninputs = list_length (inputs);
6494 noutputs = list_length (outputs);
6495 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6497 string = resolve_asm_operand_names (string, outputs, inputs);
6499 /* Remove output conversions that change the type but not the mode. */
6500 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6502 tree output = TREE_VALUE (tail);
6504 /* ??? Really, this should not be here. Users should be using a
6505 proper lvalue, dammit. But there's a long history of using casts
6506 in the output operands. In cases like longlong.h, this becomes a
6507 primitive form of typechecking -- if the cast can be removed, then
6508 the output operand had a type of the proper width; otherwise we'll
6509 get an error. Gross, but ... */
6510 STRIP_NOPS (output);
6512 if (!lvalue_or_else (output, lv_asm))
6513 output = error_mark_node;
6515 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6516 oconstraints[i] = constraint;
6518 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6519 &allows_mem, &allows_reg, &is_inout))
6521 /* If the operand is going to end up in memory,
6522 mark it addressable. */
6523 if (!allows_reg && !c_mark_addressable (output))
6524 output = error_mark_node;
6527 output = error_mark_node;
6529 TREE_VALUE (tail) = output;
6532 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6536 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6537 input = TREE_VALUE (tail);
6539 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6540 oconstraints, &allows_mem, &allows_reg))
6542 /* If the operand is going to end up in memory,
6543 mark it addressable. */
6544 if (!allows_reg && allows_mem)
6546 /* Strip the nops as we allow this case. FIXME, this really
6547 should be rejected or made deprecated. */
6549 if (!c_mark_addressable (input))
6550 input = error_mark_node;
6554 input = error_mark_node;
6556 TREE_VALUE (tail) = input;
6559 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6561 /* Simple asm statements are treated as volatile. */
6564 ASM_VOLATILE_P (args) = 1;
6565 ASM_INPUT_P (args) = 1;
6571 /* Generate a goto statement to LABEL. */
6574 c_finish_goto_label (tree label)
6576 tree decl = lookup_label (label);
6580 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6582 error ("jump into statement expression");
6586 if (C_DECL_UNJUMPABLE_VM (decl))
6588 error ("jump into scope of identifier with variably modified type");
6592 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6594 /* No jump from outside this statement expression context, so
6595 record that there is a jump from within this context. */
6596 struct c_label_list *nlist;
6597 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6598 nlist->next = label_context_stack_se->labels_used;
6599 nlist->label = decl;
6600 label_context_stack_se->labels_used = nlist;
6603 if (!C_DECL_UNDEFINABLE_VM (decl))
6605 /* No jump from outside this context context of identifiers with
6606 variably modified type, so record that there is a jump from
6607 within this context. */
6608 struct c_label_list *nlist;
6609 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6610 nlist->next = label_context_stack_vm->labels_used;
6611 nlist->label = decl;
6612 label_context_stack_vm->labels_used = nlist;
6615 TREE_USED (decl) = 1;
6616 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6619 /* Generate a computed goto statement to EXPR. */
6622 c_finish_goto_ptr (tree expr)
6625 pedwarn ("ISO C forbids %<goto *expr;%>");
6626 expr = convert (ptr_type_node, expr);
6627 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6630 /* Generate a C `return' statement. RETVAL is the expression for what
6631 to return, or a null pointer for `return;' with no value. */
6634 c_finish_return (tree retval)
6636 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6638 if (TREE_THIS_VOLATILE (current_function_decl))
6639 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6643 current_function_returns_null = 1;
6644 if ((warn_return_type || flag_isoc99)
6645 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6646 pedwarn_c99 ("%<return%> with no value, in "
6647 "function returning non-void");
6649 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6651 current_function_returns_null = 1;
6652 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6653 pedwarn ("%<return%> with a value, in function returning void");
6657 tree t = convert_for_assignment (valtype, retval, ic_return,
6658 NULL_TREE, NULL_TREE, 0);
6659 tree res = DECL_RESULT (current_function_decl);
6662 current_function_returns_value = 1;
6663 if (t == error_mark_node)
6666 inner = t = convert (TREE_TYPE (res), t);
6668 /* Strip any conversions, additions, and subtractions, and see if
6669 we are returning the address of a local variable. Warn if so. */
6672 switch (TREE_CODE (inner))
6674 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6676 inner = TREE_OPERAND (inner, 0);
6680 /* If the second operand of the MINUS_EXPR has a pointer
6681 type (or is converted from it), this may be valid, so
6682 don't give a warning. */
6684 tree op1 = TREE_OPERAND (inner, 1);
6686 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6687 && (TREE_CODE (op1) == NOP_EXPR
6688 || TREE_CODE (op1) == NON_LVALUE_EXPR
6689 || TREE_CODE (op1) == CONVERT_EXPR))
6690 op1 = TREE_OPERAND (op1, 0);
6692 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6695 inner = TREE_OPERAND (inner, 0);
6700 inner = TREE_OPERAND (inner, 0);
6702 while (REFERENCE_CLASS_P (inner)
6703 && TREE_CODE (inner) != INDIRECT_REF)
6704 inner = TREE_OPERAND (inner, 0);
6707 && !DECL_EXTERNAL (inner)
6708 && !TREE_STATIC (inner)
6709 && DECL_CONTEXT (inner) == current_function_decl)
6710 warning (0, "function returns address of local variable");
6720 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6723 return add_stmt (build_stmt (RETURN_EXPR, retval));
6727 /* The SWITCH_EXPR being built. */
6730 /* The original type of the testing expression, i.e. before the
6731 default conversion is applied. */
6734 /* A splay-tree mapping the low element of a case range to the high
6735 element, or NULL_TREE if there is no high element. Used to
6736 determine whether or not a new case label duplicates an old case
6737 label. We need a tree, rather than simply a hash table, because
6738 of the GNU case range extension. */
6741 /* Number of nested statement expressions within this switch
6742 statement; if nonzero, case and default labels may not
6744 unsigned int blocked_stmt_expr;
6746 /* Scope of outermost declarations of identifiers with variably
6747 modified type within this switch statement; if nonzero, case and
6748 default labels may not appear. */
6749 unsigned int blocked_vm;
6751 /* The next node on the stack. */
6752 struct c_switch *next;
6755 /* A stack of the currently active switch statements. The innermost
6756 switch statement is on the top of the stack. There is no need to
6757 mark the stack for garbage collection because it is only active
6758 during the processing of the body of a function, and we never
6759 collect at that point. */
6761 struct c_switch *c_switch_stack;
6763 /* Start a C switch statement, testing expression EXP. Return the new
6767 c_start_case (tree exp)
6769 enum tree_code code;
6770 tree type, orig_type = error_mark_node;
6771 struct c_switch *cs;
6773 if (exp != error_mark_node)
6775 code = TREE_CODE (TREE_TYPE (exp));
6776 orig_type = TREE_TYPE (exp);
6778 if (!INTEGRAL_TYPE_P (orig_type)
6779 && code != ERROR_MARK)
6781 error ("switch quantity not an integer");
6782 exp = integer_zero_node;
6783 orig_type = error_mark_node;
6787 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6789 if (!in_system_header
6790 && (type == long_integer_type_node
6791 || type == long_unsigned_type_node))
6792 warning (OPT_Wtraditional, "%<long%> switch expression not "
6793 "converted to %<int%> in ISO C");
6795 exp = default_conversion (exp);
6796 type = TREE_TYPE (exp);
6800 /* Add this new SWITCH_EXPR to the stack. */
6801 cs = XNEW (struct c_switch);
6802 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
6803 cs->orig_type = orig_type;
6804 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6805 cs->blocked_stmt_expr = 0;
6807 cs->next = c_switch_stack;
6808 c_switch_stack = cs;
6810 return add_stmt (cs->switch_expr);
6813 /* Process a case label. */
6816 do_case (tree low_value, tree high_value)
6818 tree label = NULL_TREE;
6820 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
6821 && !c_switch_stack->blocked_vm)
6823 label = c_add_case_label (c_switch_stack->cases,
6824 SWITCH_COND (c_switch_stack->switch_expr),
6825 c_switch_stack->orig_type,
6826 low_value, high_value);
6827 if (label == error_mark_node)
6830 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
6833 error ("case label in statement expression not containing "
6834 "enclosing switch statement");
6836 error ("%<default%> label in statement expression not containing "
6837 "enclosing switch statement");
6839 else if (c_switch_stack && c_switch_stack->blocked_vm)
6842 error ("case label in scope of identifier with variably modified "
6843 "type not containing enclosing switch statement");
6845 error ("%<default%> label in scope of identifier with variably "
6846 "modified type not containing enclosing switch statement");
6849 error ("case label not within a switch statement");
6851 error ("%<default%> label not within a switch statement");
6856 /* Finish the switch statement. */
6859 c_finish_case (tree body)
6861 struct c_switch *cs = c_switch_stack;
6862 location_t switch_location;
6864 SWITCH_BODY (cs->switch_expr) = body;
6866 /* We must not be within a statement expression nested in the switch
6867 at this point; we might, however, be within the scope of an
6868 identifier with variably modified type nested in the switch. */
6869 gcc_assert (!cs->blocked_stmt_expr);
6871 /* Emit warnings as needed. */
6872 if (EXPR_HAS_LOCATION (cs->switch_expr))
6873 switch_location = EXPR_LOCATION (cs->switch_expr);
6875 switch_location = input_location;
6876 c_do_switch_warnings (cs->cases, switch_location,
6877 TREE_TYPE (cs->switch_expr),
6878 SWITCH_COND (cs->switch_expr));
6880 /* Pop the stack. */
6881 c_switch_stack = cs->next;
6882 splay_tree_delete (cs->cases);
6886 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6887 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6888 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6889 statement, and was not surrounded with parenthesis. */
6892 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6893 tree else_block, bool nested_if)
6897 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6898 if (warn_parentheses && nested_if && else_block == NULL)
6900 tree inner_if = then_block;
6902 /* We know from the grammar productions that there is an IF nested
6903 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6904 it might not be exactly THEN_BLOCK, but should be the last
6905 non-container statement within. */
6907 switch (TREE_CODE (inner_if))
6912 inner_if = BIND_EXPR_BODY (inner_if);
6914 case STATEMENT_LIST:
6915 inner_if = expr_last (then_block);
6917 case TRY_FINALLY_EXPR:
6918 case TRY_CATCH_EXPR:
6919 inner_if = TREE_OPERAND (inner_if, 0);
6926 if (COND_EXPR_ELSE (inner_if))
6927 warning (0, "%Hsuggest explicit braces to avoid ambiguous %<else%>",
6931 /* Diagnose ";" via the special empty statement node that we create. */
6934 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6937 warning (0, "%Hempty body in an if-statement",
6938 EXPR_LOCUS (then_block));
6939 then_block = alloc_stmt_list ();
6942 && TREE_CODE (else_block) == NOP_EXPR
6943 && !TREE_TYPE (else_block))
6945 warning (0, "%Hempty body in an else-statement",
6946 EXPR_LOCUS (else_block));
6947 else_block = alloc_stmt_list ();
6951 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
6952 SET_EXPR_LOCATION (stmt, if_locus);
6956 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6957 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6958 is false for DO loops. INCR is the FOR increment expression. BODY is
6959 the statement controlled by the loop. BLAB is the break label. CLAB is
6960 the continue label. Everything is allowed to be NULL. */
6963 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6964 tree blab, tree clab, bool cond_is_first)
6966 tree entry = NULL, exit = NULL, t;
6968 /* If the condition is zero don't generate a loop construct. */
6969 if (cond && integer_zerop (cond))
6973 t = build_and_jump (&blab);
6974 SET_EXPR_LOCATION (t, start_locus);
6980 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6982 /* If we have an exit condition, then we build an IF with gotos either
6983 out of the loop, or to the top of it. If there's no exit condition,
6984 then we just build a jump back to the top. */
6985 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6987 if (cond && !integer_nonzerop (cond))
6989 /* Canonicalize the loop condition to the end. This means
6990 generating a branch to the loop condition. Reuse the
6991 continue label, if possible. */
6996 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6997 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7000 t = build1 (GOTO_EXPR, void_type_node, clab);
7001 SET_EXPR_LOCATION (t, start_locus);
7005 t = build_and_jump (&blab);
7006 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
7009 SET_EXPR_LOCATION (exit, start_locus);
7011 SET_EXPR_LOCATION (exit, input_location);
7020 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7028 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7032 c_finish_bc_stmt (tree *label_p, bool is_break)
7035 tree label = *label_p;
7037 /* In switch statements break is sometimes stylistically used after
7038 a return statement. This can lead to spurious warnings about
7039 control reaching the end of a non-void function when it is
7040 inlined. Note that we are calling block_may_fallthru with
7041 language specific tree nodes; this works because
7042 block_may_fallthru returns true when given something it does not
7044 skip = !block_may_fallthru (cur_stmt_list);
7049 *label_p = label = create_artificial_label ();
7051 else if (TREE_CODE (label) != LABEL_DECL)
7054 error ("break statement not within loop or switch");
7056 error ("continue statement not within a loop");
7063 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7066 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7069 emit_side_effect_warnings (tree expr)
7071 if (expr == error_mark_node)
7073 else if (!TREE_SIDE_EFFECTS (expr))
7075 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7076 warning (0, "%Hstatement with no effect",
7077 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7079 else if (warn_unused_value)
7080 warn_if_unused_value (expr, input_location);
7083 /* Process an expression as if it were a complete statement. Emit
7084 diagnostics, but do not call ADD_STMT. */
7087 c_process_expr_stmt (tree expr)
7092 if (warn_sequence_point)
7093 verify_sequence_points (expr);
7095 if (TREE_TYPE (expr) != error_mark_node
7096 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7097 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7098 error ("expression statement has incomplete type");
7100 /* If we're not processing a statement expression, warn about unused values.
7101 Warnings for statement expressions will be emitted later, once we figure
7102 out which is the result. */
7103 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7104 && (extra_warnings || warn_unused_value))
7105 emit_side_effect_warnings (expr);
7107 /* If the expression is not of a type to which we cannot assign a line
7108 number, wrap the thing in a no-op NOP_EXPR. */
7109 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7110 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7113 SET_EXPR_LOCATION (expr, input_location);
7118 /* Emit an expression as a statement. */
7121 c_finish_expr_stmt (tree expr)
7124 return add_stmt (c_process_expr_stmt (expr));
7129 /* Do the opposite and emit a statement as an expression. To begin,
7130 create a new binding level and return it. */
7133 c_begin_stmt_expr (void)
7136 struct c_label_context_se *nstack;
7137 struct c_label_list *glist;
7139 /* We must force a BLOCK for this level so that, if it is not expanded
7140 later, there is a way to turn off the entire subtree of blocks that
7141 are contained in it. */
7143 ret = c_begin_compound_stmt (true);
7146 c_switch_stack->blocked_stmt_expr++;
7147 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7149 for (glist = label_context_stack_se->labels_used;
7151 glist = glist->next)
7153 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7155 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7156 nstack->labels_def = NULL;
7157 nstack->labels_used = NULL;
7158 nstack->next = label_context_stack_se;
7159 label_context_stack_se = nstack;
7161 /* Mark the current statement list as belonging to a statement list. */
7162 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7168 c_finish_stmt_expr (tree body)
7170 tree last, type, tmp, val;
7172 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7174 body = c_end_compound_stmt (body, true);
7177 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7178 c_switch_stack->blocked_stmt_expr--;
7180 /* It is no longer possible to jump to labels defined within this
7181 statement expression. */
7182 for (dlist = label_context_stack_se->labels_def;
7184 dlist = dlist->next)
7186 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7188 /* It is again possible to define labels with a goto just outside
7189 this statement expression. */
7190 for (glist = label_context_stack_se->next->labels_used;
7192 glist = glist->next)
7194 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7197 if (glist_prev != NULL)
7198 glist_prev->next = label_context_stack_se->labels_used;
7200 label_context_stack_se->next->labels_used
7201 = label_context_stack_se->labels_used;
7202 label_context_stack_se = label_context_stack_se->next;
7204 /* Locate the last statement in BODY. See c_end_compound_stmt
7205 about always returning a BIND_EXPR. */
7206 last_p = &BIND_EXPR_BODY (body);
7207 last = BIND_EXPR_BODY (body);
7210 if (TREE_CODE (last) == STATEMENT_LIST)
7212 tree_stmt_iterator i;
7214 /* This can happen with degenerate cases like ({ }). No value. */
7215 if (!TREE_SIDE_EFFECTS (last))
7218 /* If we're supposed to generate side effects warnings, process
7219 all of the statements except the last. */
7220 if (extra_warnings || warn_unused_value)
7222 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7223 emit_side_effect_warnings (tsi_stmt (i));
7226 i = tsi_last (last);
7227 last_p = tsi_stmt_ptr (i);
7231 /* If the end of the list is exception related, then the list was split
7232 by a call to push_cleanup. Continue searching. */
7233 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7234 || TREE_CODE (last) == TRY_CATCH_EXPR)
7236 last_p = &TREE_OPERAND (last, 0);
7238 goto continue_searching;
7241 /* In the case that the BIND_EXPR is not necessary, return the
7242 expression out from inside it. */
7243 if (last == error_mark_node
7244 || (last == BIND_EXPR_BODY (body)
7245 && BIND_EXPR_VARS (body) == NULL))
7248 /* Extract the type of said expression. */
7249 type = TREE_TYPE (last);
7251 /* If we're not returning a value at all, then the BIND_EXPR that
7252 we already have is a fine expression to return. */
7253 if (!type || VOID_TYPE_P (type))
7256 /* Now that we've located the expression containing the value, it seems
7257 silly to make voidify_wrapper_expr repeat the process. Create a
7258 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7259 tmp = create_tmp_var_raw (type, NULL);
7261 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7262 tree_expr_nonnegative_p giving up immediately. */
7264 if (TREE_CODE (val) == NOP_EXPR
7265 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7266 val = TREE_OPERAND (val, 0);
7268 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7269 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7271 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7274 /* Begin the scope of an identifier of variably modified type, scope
7275 number SCOPE. Jumping from outside this scope to inside it is not
7279 c_begin_vm_scope (unsigned int scope)
7281 struct c_label_context_vm *nstack;
7282 struct c_label_list *glist;
7284 gcc_assert (scope > 0);
7285 if (c_switch_stack && !c_switch_stack->blocked_vm)
7286 c_switch_stack->blocked_vm = scope;
7287 for (glist = label_context_stack_vm->labels_used;
7289 glist = glist->next)
7291 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7293 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7294 nstack->labels_def = NULL;
7295 nstack->labels_used = NULL;
7296 nstack->scope = scope;
7297 nstack->next = label_context_stack_vm;
7298 label_context_stack_vm = nstack;
7301 /* End a scope which may contain identifiers of variably modified
7302 type, scope number SCOPE. */
7305 c_end_vm_scope (unsigned int scope)
7307 if (label_context_stack_vm == NULL)
7309 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7310 c_switch_stack->blocked_vm = 0;
7311 /* We may have a number of nested scopes of identifiers with
7312 variably modified type, all at this depth. Pop each in turn. */
7313 while (label_context_stack_vm->scope == scope)
7315 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7317 /* It is no longer possible to jump to labels defined within this
7319 for (dlist = label_context_stack_vm->labels_def;
7321 dlist = dlist->next)
7323 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7325 /* It is again possible to define labels with a goto just outside
7327 for (glist = label_context_stack_vm->next->labels_used;
7329 glist = glist->next)
7331 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7334 if (glist_prev != NULL)
7335 glist_prev->next = label_context_stack_vm->labels_used;
7337 label_context_stack_vm->next->labels_used
7338 = label_context_stack_vm->labels_used;
7339 label_context_stack_vm = label_context_stack_vm->next;
7343 /* Begin and end compound statements. This is as simple as pushing
7344 and popping new statement lists from the tree. */
7347 c_begin_compound_stmt (bool do_scope)
7349 tree stmt = push_stmt_list ();
7356 c_end_compound_stmt (tree stmt, bool do_scope)
7362 if (c_dialect_objc ())
7363 objc_clear_super_receiver ();
7364 block = pop_scope ();
7367 stmt = pop_stmt_list (stmt);
7368 stmt = c_build_bind_expr (block, stmt);
7370 /* If this compound statement is nested immediately inside a statement
7371 expression, then force a BIND_EXPR to be created. Otherwise we'll
7372 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7373 STATEMENT_LISTs merge, and thus we can lose track of what statement
7376 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7377 && TREE_CODE (stmt) != BIND_EXPR)
7379 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7380 TREE_SIDE_EFFECTS (stmt) = 1;
7386 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7387 when the current scope is exited. EH_ONLY is true when this is not
7388 meant to apply to normal control flow transfer. */
7391 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7393 enum tree_code code;
7397 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7398 stmt = build_stmt (code, NULL, cleanup);
7400 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7401 list = push_stmt_list ();
7402 TREE_OPERAND (stmt, 0) = list;
7403 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7406 /* Build a binary-operation expression without default conversions.
7407 CODE is the kind of expression to build.
7408 This function differs from `build' in several ways:
7409 the data type of the result is computed and recorded in it,
7410 warnings are generated if arg data types are invalid,
7411 special handling for addition and subtraction of pointers is known,
7412 and some optimization is done (operations on narrow ints
7413 are done in the narrower type when that gives the same result).
7414 Constant folding is also done before the result is returned.
7416 Note that the operands will never have enumeral types, or function
7417 or array types, because either they will have the default conversions
7418 performed or they have both just been converted to some other type in which
7419 the arithmetic is to be done. */
7422 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7426 enum tree_code code0, code1;
7428 const char *invalid_op_diag;
7430 /* Expression code to give to the expression when it is built.
7431 Normally this is CODE, which is what the caller asked for,
7432 but in some special cases we change it. */
7433 enum tree_code resultcode = code;
7435 /* Data type in which the computation is to be performed.
7436 In the simplest cases this is the common type of the arguments. */
7437 tree result_type = NULL;
7439 /* Nonzero means operands have already been type-converted
7440 in whatever way is necessary.
7441 Zero means they need to be converted to RESULT_TYPE. */
7444 /* Nonzero means create the expression with this type, rather than
7446 tree build_type = 0;
7448 /* Nonzero means after finally constructing the expression
7449 convert it to this type. */
7450 tree final_type = 0;
7452 /* Nonzero if this is an operation like MIN or MAX which can
7453 safely be computed in short if both args are promoted shorts.
7454 Also implies COMMON.
7455 -1 indicates a bitwise operation; this makes a difference
7456 in the exact conditions for when it is safe to do the operation
7457 in a narrower mode. */
7460 /* Nonzero if this is a comparison operation;
7461 if both args are promoted shorts, compare the original shorts.
7462 Also implies COMMON. */
7463 int short_compare = 0;
7465 /* Nonzero if this is a right-shift operation, which can be computed on the
7466 original short and then promoted if the operand is a promoted short. */
7467 int short_shift = 0;
7469 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7472 /* True means types are compatible as far as ObjC is concerned. */
7477 op0 = default_conversion (orig_op0);
7478 op1 = default_conversion (orig_op1);
7486 type0 = TREE_TYPE (op0);
7487 type1 = TREE_TYPE (op1);
7489 /* The expression codes of the data types of the arguments tell us
7490 whether the arguments are integers, floating, pointers, etc. */
7491 code0 = TREE_CODE (type0);
7492 code1 = TREE_CODE (type1);
7494 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7495 STRIP_TYPE_NOPS (op0);
7496 STRIP_TYPE_NOPS (op1);
7498 /* If an error was already reported for one of the arguments,
7499 avoid reporting another error. */
7501 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7502 return error_mark_node;
7504 if ((invalid_op_diag
7505 = targetm.invalid_binary_op (code, type0, type1)))
7507 error (invalid_op_diag);
7508 return error_mark_node;
7511 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7516 /* Handle the pointer + int case. */
7517 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7518 return pointer_int_sum (PLUS_EXPR, op0, op1);
7519 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7520 return pointer_int_sum (PLUS_EXPR, op1, op0);
7526 /* Subtraction of two similar pointers.
7527 We must subtract them as integers, then divide by object size. */
7528 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7529 && comp_target_types (type0, type1))
7530 return pointer_diff (op0, op1);
7531 /* Handle pointer minus int. Just like pointer plus int. */
7532 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7533 return pointer_int_sum (MINUS_EXPR, op0, op1);
7542 case TRUNC_DIV_EXPR:
7544 case FLOOR_DIV_EXPR:
7545 case ROUND_DIV_EXPR:
7546 case EXACT_DIV_EXPR:
7547 /* Floating point division by zero is a legitimate way to obtain
7548 infinities and NaNs. */
7549 if (skip_evaluation == 0 && integer_zerop (op1))
7550 warning (OPT_Wdiv_by_zero, "division by zero");
7552 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7553 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7554 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7555 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7557 enum tree_code tcode0 = code0, tcode1 = code1;
7559 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7560 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7561 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7562 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7564 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7565 resultcode = RDIV_EXPR;
7567 /* Although it would be tempting to shorten always here, that
7568 loses on some targets, since the modulo instruction is
7569 undefined if the quotient can't be represented in the
7570 computation mode. We shorten only if unsigned or if
7571 dividing by something we know != -1. */
7572 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7573 || (TREE_CODE (op1) == INTEGER_CST
7574 && !integer_all_onesp (op1)));
7582 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7584 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7588 case TRUNC_MOD_EXPR:
7589 case FLOOR_MOD_EXPR:
7590 if (skip_evaluation == 0 && integer_zerop (op1))
7591 warning (OPT_Wdiv_by_zero, "division by zero");
7593 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7595 /* Although it would be tempting to shorten always here, that loses
7596 on some targets, since the modulo instruction is undefined if the
7597 quotient can't be represented in the computation mode. We shorten
7598 only if unsigned or if dividing by something we know != -1. */
7599 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7600 || (TREE_CODE (op1) == INTEGER_CST
7601 && !integer_all_onesp (op1)));
7606 case TRUTH_ANDIF_EXPR:
7607 case TRUTH_ORIF_EXPR:
7608 case TRUTH_AND_EXPR:
7610 case TRUTH_XOR_EXPR:
7611 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7612 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7613 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7614 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7616 /* Result of these operations is always an int,
7617 but that does not mean the operands should be
7618 converted to ints! */
7619 result_type = integer_type_node;
7620 op0 = c_common_truthvalue_conversion (op0);
7621 op1 = c_common_truthvalue_conversion (op1);
7626 /* Shift operations: result has same type as first operand;
7627 always convert second operand to int.
7628 Also set SHORT_SHIFT if shifting rightward. */
7631 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7633 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7635 if (tree_int_cst_sgn (op1) < 0)
7636 warning (0, "right shift count is negative");
7639 if (!integer_zerop (op1))
7642 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7643 warning (0, "right shift count >= width of type");
7647 /* Use the type of the value to be shifted. */
7648 result_type = type0;
7649 /* Convert the shift-count to an integer, regardless of size
7650 of value being shifted. */
7651 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7652 op1 = convert (integer_type_node, op1);
7653 /* Avoid converting op1 to result_type later. */
7659 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7661 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7663 if (tree_int_cst_sgn (op1) < 0)
7664 warning (0, "left shift count is negative");
7666 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7667 warning (0, "left shift count >= width of type");
7670 /* Use the type of the value to be shifted. */
7671 result_type = type0;
7672 /* Convert the shift-count to an integer, regardless of size
7673 of value being shifted. */
7674 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7675 op1 = convert (integer_type_node, op1);
7676 /* Avoid converting op1 to result_type later. */
7683 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7684 warning (OPT_Wfloat_equal,
7685 "comparing floating point with == or != is unsafe");
7686 /* Result of comparison is always int,
7687 but don't convert the args to int! */
7688 build_type = integer_type_node;
7689 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7690 || code0 == COMPLEX_TYPE)
7691 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7692 || code1 == COMPLEX_TYPE))
7694 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7696 tree tt0 = TREE_TYPE (type0);
7697 tree tt1 = TREE_TYPE (type1);
7698 /* Anything compares with void *. void * compares with anything.
7699 Otherwise, the targets must be compatible
7700 and both must be object or both incomplete. */
7701 if (comp_target_types (type0, type1))
7702 result_type = common_pointer_type (type0, type1);
7703 else if (VOID_TYPE_P (tt0))
7705 /* op0 != orig_op0 detects the case of something
7706 whose value is 0 but which isn't a valid null ptr const. */
7707 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7708 && TREE_CODE (tt1) == FUNCTION_TYPE)
7709 pedwarn ("ISO C forbids comparison of %<void *%>"
7710 " with function pointer");
7712 else if (VOID_TYPE_P (tt1))
7714 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7715 && TREE_CODE (tt0) == FUNCTION_TYPE)
7716 pedwarn ("ISO C forbids comparison of %<void *%>"
7717 " with function pointer");
7720 /* Avoid warning about the volatile ObjC EH puts on decls. */
7722 pedwarn ("comparison of distinct pointer types lacks a cast");
7724 if (result_type == NULL_TREE)
7725 result_type = ptr_type_node;
7727 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7728 && integer_zerop (op1))
7729 result_type = type0;
7730 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7731 && integer_zerop (op0))
7732 result_type = type1;
7733 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7735 result_type = type0;
7736 pedwarn ("comparison between pointer and integer");
7738 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7740 result_type = type1;
7741 pedwarn ("comparison between pointer and integer");
7749 build_type = integer_type_node;
7750 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7751 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7753 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7755 if (comp_target_types (type0, type1))
7757 result_type = common_pointer_type (type0, type1);
7758 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7759 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7760 pedwarn ("comparison of complete and incomplete pointers");
7762 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7763 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7767 result_type = ptr_type_node;
7768 pedwarn ("comparison of distinct pointer types lacks a cast");
7771 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7772 && integer_zerop (op1))
7774 result_type = type0;
7775 if (pedantic || extra_warnings)
7776 pedwarn ("ordered comparison of pointer with integer zero");
7778 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7779 && integer_zerop (op0))
7781 result_type = type1;
7783 pedwarn ("ordered comparison of pointer with integer zero");
7785 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7787 result_type = type0;
7788 pedwarn ("comparison between pointer and integer");
7790 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7792 result_type = type1;
7793 pedwarn ("comparison between pointer and integer");
7801 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7802 return error_mark_node;
7804 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
7805 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
7806 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
7807 TREE_TYPE (type1))))
7809 binary_op_error (code);
7810 return error_mark_node;
7813 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7814 || code0 == VECTOR_TYPE)
7816 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7817 || code1 == VECTOR_TYPE))
7819 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7821 if (shorten || common || short_compare)
7822 result_type = c_common_type (type0, type1);
7824 /* For certain operations (which identify themselves by shorten != 0)
7825 if both args were extended from the same smaller type,
7826 do the arithmetic in that type and then extend.
7828 shorten !=0 and !=1 indicates a bitwise operation.
7829 For them, this optimization is safe only if
7830 both args are zero-extended or both are sign-extended.
7831 Otherwise, we might change the result.
7832 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7833 but calculated in (unsigned short) it would be (unsigned short)-1. */
7835 if (shorten && none_complex)
7837 int unsigned0, unsigned1;
7838 tree arg0 = get_narrower (op0, &unsigned0);
7839 tree arg1 = get_narrower (op1, &unsigned1);
7840 /* UNS is 1 if the operation to be done is an unsigned one. */
7841 int uns = TYPE_UNSIGNED (result_type);
7844 final_type = result_type;
7846 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7847 but it *requires* conversion to FINAL_TYPE. */
7849 if ((TYPE_PRECISION (TREE_TYPE (op0))
7850 == TYPE_PRECISION (TREE_TYPE (arg0)))
7851 && TREE_TYPE (op0) != final_type)
7852 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7853 if ((TYPE_PRECISION (TREE_TYPE (op1))
7854 == TYPE_PRECISION (TREE_TYPE (arg1)))
7855 && TREE_TYPE (op1) != final_type)
7856 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7858 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7860 /* For bitwise operations, signedness of nominal type
7861 does not matter. Consider only how operands were extended. */
7865 /* Note that in all three cases below we refrain from optimizing
7866 an unsigned operation on sign-extended args.
7867 That would not be valid. */
7869 /* Both args variable: if both extended in same way
7870 from same width, do it in that width.
7871 Do it unsigned if args were zero-extended. */
7872 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7873 < TYPE_PRECISION (result_type))
7874 && (TYPE_PRECISION (TREE_TYPE (arg1))
7875 == TYPE_PRECISION (TREE_TYPE (arg0)))
7876 && unsigned0 == unsigned1
7877 && (unsigned0 || !uns))
7879 = c_common_signed_or_unsigned_type
7880 (unsigned0, c_common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7881 else if (TREE_CODE (arg0) == INTEGER_CST
7882 && (unsigned1 || !uns)
7883 && (TYPE_PRECISION (TREE_TYPE (arg1))
7884 < TYPE_PRECISION (result_type))
7886 = c_common_signed_or_unsigned_type (unsigned1,
7888 int_fits_type_p (arg0, type)))
7890 else if (TREE_CODE (arg1) == INTEGER_CST
7891 && (unsigned0 || !uns)
7892 && (TYPE_PRECISION (TREE_TYPE (arg0))
7893 < TYPE_PRECISION (result_type))
7895 = c_common_signed_or_unsigned_type (unsigned0,
7897 int_fits_type_p (arg1, type)))
7901 /* Shifts can be shortened if shifting right. */
7906 tree arg0 = get_narrower (op0, &unsigned_arg);
7908 final_type = result_type;
7910 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7911 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7913 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7914 /* We can shorten only if the shift count is less than the
7915 number of bits in the smaller type size. */
7916 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7917 /* We cannot drop an unsigned shift after sign-extension. */
7918 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7920 /* Do an unsigned shift if the operand was zero-extended. */
7922 = c_common_signed_or_unsigned_type (unsigned_arg,
7924 /* Convert value-to-be-shifted to that type. */
7925 if (TREE_TYPE (op0) != result_type)
7926 op0 = convert (result_type, op0);
7931 /* Comparison operations are shortened too but differently.
7932 They identify themselves by setting short_compare = 1. */
7936 /* Don't write &op0, etc., because that would prevent op0
7937 from being kept in a register.
7938 Instead, make copies of the our local variables and
7939 pass the copies by reference, then copy them back afterward. */
7940 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7941 enum tree_code xresultcode = resultcode;
7943 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7948 op0 = xop0, op1 = xop1;
7950 resultcode = xresultcode;
7952 if (warn_sign_compare && skip_evaluation == 0)
7954 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7955 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7956 int unsignedp0, unsignedp1;
7957 tree primop0 = get_narrower (op0, &unsignedp0);
7958 tree primop1 = get_narrower (op1, &unsignedp1);
7962 STRIP_TYPE_NOPS (xop0);
7963 STRIP_TYPE_NOPS (xop1);
7965 /* Give warnings for comparisons between signed and unsigned
7966 quantities that may fail.
7968 Do the checking based on the original operand trees, so that
7969 casts will be considered, but default promotions won't be.
7971 Do not warn if the comparison is being done in a signed type,
7972 since the signed type will only be chosen if it can represent
7973 all the values of the unsigned type. */
7974 if (!TYPE_UNSIGNED (result_type))
7976 /* Do not warn if both operands are the same signedness. */
7977 else if (op0_signed == op1_signed)
7984 sop = xop0, uop = xop1;
7986 sop = xop1, uop = xop0;
7988 /* Do not warn if the signed quantity is an
7989 unsuffixed integer literal (or some static
7990 constant expression involving such literals or a
7991 conditional expression involving such literals)
7992 and it is non-negative. */
7993 if (tree_expr_nonnegative_p (sop))
7995 /* Do not warn if the comparison is an equality operation,
7996 the unsigned quantity is an integral constant, and it
7997 would fit in the result if the result were signed. */
7998 else if (TREE_CODE (uop) == INTEGER_CST
7999 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8001 (uop, c_common_signed_type (result_type)))
8003 /* Do not warn if the unsigned quantity is an enumeration
8004 constant and its maximum value would fit in the result
8005 if the result were signed. */
8006 else if (TREE_CODE (uop) == INTEGER_CST
8007 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8009 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8010 c_common_signed_type (result_type)))
8013 warning (0, "comparison between signed and unsigned");
8016 /* Warn if two unsigned values are being compared in a size
8017 larger than their original size, and one (and only one) is the
8018 result of a `~' operator. This comparison will always fail.
8020 Also warn if one operand is a constant, and the constant
8021 does not have all bits set that are set in the ~ operand
8022 when it is extended. */
8024 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8025 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8027 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8028 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8031 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8034 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8037 HOST_WIDE_INT constant, mask;
8038 int unsignedp, bits;
8040 if (host_integerp (primop0, 0))
8043 unsignedp = unsignedp1;
8044 constant = tree_low_cst (primop0, 0);
8049 unsignedp = unsignedp0;
8050 constant = tree_low_cst (primop1, 0);
8053 bits = TYPE_PRECISION (TREE_TYPE (primop));
8054 if (bits < TYPE_PRECISION (result_type)
8055 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8057 mask = (~(HOST_WIDE_INT) 0) << bits;
8058 if ((mask & constant) != mask)
8059 warning (0, "comparison of promoted ~unsigned with constant");
8062 else if (unsignedp0 && unsignedp1
8063 && (TYPE_PRECISION (TREE_TYPE (primop0))
8064 < TYPE_PRECISION (result_type))
8065 && (TYPE_PRECISION (TREE_TYPE (primop1))
8066 < TYPE_PRECISION (result_type)))
8067 warning (0, "comparison of promoted ~unsigned with unsigned");
8073 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8074 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8075 Then the expression will be built.
8076 It will be given type FINAL_TYPE if that is nonzero;
8077 otherwise, it will be given type RESULT_TYPE. */
8081 binary_op_error (code);
8082 return error_mark_node;
8087 if (TREE_TYPE (op0) != result_type)
8088 op0 = convert (result_type, op0);
8089 if (TREE_TYPE (op1) != result_type)
8090 op1 = convert (result_type, op1);
8092 /* This can happen if one operand has a vector type, and the other
8093 has a different type. */
8094 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8095 return error_mark_node;
8098 if (build_type == NULL_TREE)
8099 build_type = result_type;
8102 tree result = build2 (resultcode, build_type, op0, op1);
8104 /* Treat expressions in initializers specially as they can't trap. */
8105 result = require_constant_value ? fold_initializer (result)
8108 if (final_type != 0)
8109 result = convert (final_type, result);
8115 /* Convert EXPR to be a truth-value, validating its type for this
8119 c_objc_common_truthvalue_conversion (tree expr)
8121 switch (TREE_CODE (TREE_TYPE (expr)))
8124 error ("used array that cannot be converted to pointer where scalar is required");
8125 return error_mark_node;
8128 error ("used struct type value where scalar is required");
8129 return error_mark_node;
8132 error ("used union type value where scalar is required");
8133 return error_mark_node;
8142 /* ??? Should we also give an error for void and vectors rather than
8143 leaving those to give errors later? */
8144 return c_common_truthvalue_conversion (expr);
8148 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8152 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8153 bool *ti ATTRIBUTE_UNUSED, bool *se)
8155 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8157 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8158 /* Executing a compound literal inside a function reinitializes
8160 if (!TREE_STATIC (decl))