1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization. */
30 #include "coretypes.h"
34 #include "langhooks.h"
44 #include "tree-iterator.h"
45 #include "tree-gimple.h"
46 #include "tree-flow.h"
48 /* Possible cases of implicit bad conversions. Used to select
49 diagnostic messages in convert_for_assignment. */
58 /* The level of nesting inside "__alignof__". */
61 /* The level of nesting inside "sizeof". */
64 /* The level of nesting inside "typeof". */
67 struct c_label_context_se *label_context_stack_se;
68 struct c_label_context_vm *label_context_stack_vm;
70 /* Nonzero if we've already printed a "missing braces around initializer"
71 message within this initializer. */
72 static int missing_braces_mentioned;
74 static int require_constant_value;
75 static int require_constant_elements;
77 static tree qualify_type (tree, tree);
78 static int tagged_types_tu_compatible_p (tree, tree);
79 static int comp_target_types (tree, tree);
80 static int function_types_compatible_p (tree, tree);
81 static int type_lists_compatible_p (tree, tree);
82 static tree decl_constant_value_for_broken_optimization (tree);
83 static tree default_function_array_conversion (tree);
84 static tree lookup_field (tree, tree);
85 static tree convert_arguments (tree, tree, tree, tree);
86 static tree pointer_diff (tree, tree);
87 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 static tree valid_compound_expr_initializer (tree, tree);
90 static void push_string (const char *);
91 static void push_member_name (tree);
92 static void push_array_bounds (int);
93 static int spelling_length (void);
94 static char *print_spelling (char *);
95 static void warning_init (const char *);
96 static tree digest_init (tree, tree, bool, int);
97 static void output_init_element (tree, bool, tree, tree, int);
98 static void output_pending_init_elements (int);
99 static int set_designator (int);
100 static void push_range_stack (tree);
101 static void add_pending_init (tree, tree);
102 static void set_nonincremental_init (void);
103 static void set_nonincremental_init_from_string (tree);
104 static tree find_init_member (tree);
105 static void readonly_error (tree, enum lvalue_use);
106 static int lvalue_or_else (tree, enum lvalue_use);
107 static int lvalue_p (tree);
108 static void record_maybe_used_decl (tree);
110 /* Do `exp = require_complete_type (exp);' to make sure exp
111 does not have an incomplete type. (That includes void types.) */
114 require_complete_type (tree value)
116 tree type = TREE_TYPE (value);
118 if (value == error_mark_node || type == error_mark_node)
119 return error_mark_node;
121 /* First, detect a valid value with a complete type. */
122 if (COMPLETE_TYPE_P (type))
125 c_incomplete_type_error (value, type);
126 return error_mark_node;
129 /* Print an error message for invalid use of an incomplete type.
130 VALUE is the expression that was used (or 0 if that isn't known)
131 and TYPE is the type that was invalid. */
134 c_incomplete_type_error (tree value, tree type)
136 const char *type_code_string;
138 /* Avoid duplicate error message. */
139 if (TREE_CODE (type) == ERROR_MARK)
142 if (value != 0 && (TREE_CODE (value) == VAR_DECL
143 || TREE_CODE (value) == PARM_DECL))
144 error ("%qD has an incomplete type", value);
148 /* We must print an error message. Be clever about what it says. */
150 switch (TREE_CODE (type))
153 type_code_string = "struct";
157 type_code_string = "union";
161 type_code_string = "enum";
165 error ("invalid use of void expression");
169 if (TYPE_DOMAIN (type))
171 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
173 error ("invalid use of flexible array member");
176 type = TREE_TYPE (type);
179 error ("invalid use of array with unspecified bounds");
186 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
187 error ("invalid use of undefined type %<%s %E%>",
188 type_code_string, TYPE_NAME (type));
190 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
191 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
195 /* Given a type, apply default promotions wrt unnamed function
196 arguments and return the new type. */
199 c_type_promotes_to (tree type)
201 if (TYPE_MAIN_VARIANT (type) == float_type_node)
202 return double_type_node;
204 if (c_promoting_integer_type_p (type))
206 /* Preserve unsignedness if not really getting any wider. */
207 if (TYPE_UNSIGNED (type)
208 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
209 return unsigned_type_node;
210 return integer_type_node;
216 /* Return a variant of TYPE which has all the type qualifiers of LIKE
217 as well as those of TYPE. */
220 qualify_type (tree type, tree like)
222 return c_build_qualified_type (type,
223 TYPE_QUALS (type) | TYPE_QUALS (like));
226 /* Return the composite type of two compatible types.
228 We assume that comptypes has already been done and returned
229 nonzero; if that isn't so, this may crash. In particular, we
230 assume that qualifiers match. */
233 composite_type (tree t1, tree t2)
235 enum tree_code code1;
236 enum tree_code code2;
239 /* Save time if the two types are the same. */
241 if (t1 == t2) return t1;
243 /* If one type is nonsense, use the other. */
244 if (t1 == error_mark_node)
246 if (t2 == error_mark_node)
249 code1 = TREE_CODE (t1);
250 code2 = TREE_CODE (t2);
252 /* Merge the attributes. */
253 attributes = targetm.merge_type_attributes (t1, t2);
255 /* If one is an enumerated type and the other is the compatible
256 integer type, the composite type might be either of the two
257 (DR#013 question 3). For consistency, use the enumerated type as
258 the composite type. */
260 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
262 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
265 gcc_assert (code1 == code2);
270 /* For two pointers, do this recursively on the target type. */
272 tree pointed_to_1 = TREE_TYPE (t1);
273 tree pointed_to_2 = TREE_TYPE (t2);
274 tree target = composite_type (pointed_to_1, pointed_to_2);
275 t1 = build_pointer_type (target);
276 t1 = build_type_attribute_variant (t1, attributes);
277 return qualify_type (t1, t2);
282 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
286 /* We should not have any type quals on arrays at all. */
287 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
289 /* Save space: see if the result is identical to one of the args. */
290 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
291 return build_type_attribute_variant (t1, attributes);
292 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
293 return build_type_attribute_variant (t2, attributes);
295 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
296 return build_type_attribute_variant (t1, attributes);
297 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
298 return build_type_attribute_variant (t2, attributes);
300 /* Merge the element types, and have a size if either arg has
301 one. We may have qualifiers on the element types. To set
302 up TYPE_MAIN_VARIANT correctly, we need to form the
303 composite of the unqualified types and add the qualifiers
305 quals = TYPE_QUALS (strip_array_types (elt));
306 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
307 t1 = build_array_type (unqual_elt,
308 TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
309 t1 = c_build_qualified_type (t1, quals);
310 return build_type_attribute_variant (t1, attributes);
314 /* Function types: prefer the one that specified arg types.
315 If both do, merge the arg types. Also merge the return types. */
317 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
318 tree p1 = TYPE_ARG_TYPES (t1);
319 tree p2 = TYPE_ARG_TYPES (t2);
324 /* Save space: see if the result is identical to one of the args. */
325 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
326 return build_type_attribute_variant (t1, attributes);
327 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
328 return build_type_attribute_variant (t2, attributes);
330 /* Simple way if one arg fails to specify argument types. */
331 if (TYPE_ARG_TYPES (t1) == 0)
333 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
334 t1 = build_type_attribute_variant (t1, attributes);
335 return qualify_type (t1, t2);
337 if (TYPE_ARG_TYPES (t2) == 0)
339 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
340 t1 = build_type_attribute_variant (t1, attributes);
341 return qualify_type (t1, t2);
344 /* If both args specify argument types, we must merge the two
345 lists, argument by argument. */
346 /* Tell global_bindings_p to return false so that variable_size
347 doesn't die on VLAs in parameter types. */
348 c_override_global_bindings_to_false = true;
350 len = list_length (p1);
353 for (i = 0; i < len; i++)
354 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
359 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
361 /* A null type means arg type is not specified.
362 Take whatever the other function type has. */
363 if (TREE_VALUE (p1) == 0)
365 TREE_VALUE (n) = TREE_VALUE (p2);
368 if (TREE_VALUE (p2) == 0)
370 TREE_VALUE (n) = TREE_VALUE (p1);
374 /* Given wait (union {union wait *u; int *i} *)
375 and wait (union wait *),
376 prefer union wait * as type of parm. */
377 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
378 && TREE_VALUE (p1) != TREE_VALUE (p2))
381 tree mv2 = TREE_VALUE (p2);
382 if (mv2 && mv2 != error_mark_node
383 && TREE_CODE (mv2) != ARRAY_TYPE)
384 mv2 = TYPE_MAIN_VARIANT (mv2);
385 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
386 memb; memb = TREE_CHAIN (memb))
388 tree mv3 = TREE_TYPE (memb);
389 if (mv3 && mv3 != error_mark_node
390 && TREE_CODE (mv3) != ARRAY_TYPE)
391 mv3 = TYPE_MAIN_VARIANT (mv3);
392 if (comptypes (mv3, mv2))
394 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
397 pedwarn ("function types not truly compatible in ISO C");
402 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
403 && TREE_VALUE (p2) != TREE_VALUE (p1))
406 tree mv1 = TREE_VALUE (p1);
407 if (mv1 && mv1 != error_mark_node
408 && TREE_CODE (mv1) != ARRAY_TYPE)
409 mv1 = TYPE_MAIN_VARIANT (mv1);
410 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
411 memb; memb = TREE_CHAIN (memb))
413 tree mv3 = TREE_TYPE (memb);
414 if (mv3 && mv3 != error_mark_node
415 && TREE_CODE (mv3) != ARRAY_TYPE)
416 mv3 = TYPE_MAIN_VARIANT (mv3);
417 if (comptypes (mv3, mv1))
419 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
422 pedwarn ("function types not truly compatible in ISO C");
427 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
431 c_override_global_bindings_to_false = false;
432 t1 = build_function_type (valtype, newargs);
433 t1 = qualify_type (t1, t2);
434 /* ... falls through ... */
438 return build_type_attribute_variant (t1, attributes);
443 /* Return the type of a conditional expression between pointers to
444 possibly differently qualified versions of compatible types.
446 We assume that comp_target_types has already been done and returned
447 nonzero; if that isn't so, this may crash. */
450 common_pointer_type (tree t1, tree t2)
453 tree pointed_to_1, mv1;
454 tree pointed_to_2, mv2;
457 /* Save time if the two types are the same. */
459 if (t1 == t2) return t1;
461 /* If one type is nonsense, use the other. */
462 if (t1 == error_mark_node)
464 if (t2 == error_mark_node)
467 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
468 && TREE_CODE (t2) == POINTER_TYPE);
470 /* Merge the attributes. */
471 attributes = targetm.merge_type_attributes (t1, t2);
473 /* Find the composite type of the target types, and combine the
474 qualifiers of the two types' targets. Do not lose qualifiers on
475 array element types by taking the TYPE_MAIN_VARIANT. */
476 mv1 = pointed_to_1 = TREE_TYPE (t1);
477 mv2 = pointed_to_2 = TREE_TYPE (t2);
478 if (TREE_CODE (mv1) != ARRAY_TYPE)
479 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
480 if (TREE_CODE (mv2) != ARRAY_TYPE)
481 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
482 target = composite_type (mv1, mv2);
483 t1 = build_pointer_type (c_build_qualified_type
485 TYPE_QUALS (pointed_to_1) |
486 TYPE_QUALS (pointed_to_2)));
487 return build_type_attribute_variant (t1, attributes);
490 /* Return the common type for two arithmetic types under the usual
491 arithmetic conversions. The default conversions have already been
492 applied, and enumerated types converted to their compatible integer
493 types. The resulting type is unqualified and has no attributes.
495 This is the type for the result of most arithmetic operations
496 if the operands have the given two types. */
499 c_common_type (tree t1, tree t2)
501 enum tree_code code1;
502 enum tree_code code2;
504 /* If one type is nonsense, use the other. */
505 if (t1 == error_mark_node)
507 if (t2 == error_mark_node)
510 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
511 t1 = TYPE_MAIN_VARIANT (t1);
513 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
514 t2 = TYPE_MAIN_VARIANT (t2);
516 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
517 t1 = build_type_attribute_variant (t1, NULL_TREE);
519 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
520 t2 = build_type_attribute_variant (t2, NULL_TREE);
522 /* Save time if the two types are the same. */
524 if (t1 == t2) return t1;
526 code1 = TREE_CODE (t1);
527 code2 = TREE_CODE (t2);
529 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
530 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
531 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
532 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
534 /* If one type is a vector type, return that type. (How the usual
535 arithmetic conversions apply to the vector types extension is not
536 precisely specified.) */
537 if (code1 == VECTOR_TYPE)
540 if (code2 == VECTOR_TYPE)
543 /* If one type is complex, form the common type of the non-complex
544 components, then make that complex. Use T1 or T2 if it is the
546 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
548 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
549 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
550 tree subtype = c_common_type (subtype1, subtype2);
552 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
554 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
557 return build_complex_type (subtype);
560 /* If only one is real, use it as the result. */
562 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
565 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
568 /* Both real or both integers; use the one with greater precision. */
570 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
572 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
575 /* Same precision. Prefer long longs to longs to ints when the
576 same precision, following the C99 rules on integer type rank
577 (which are equivalent to the C90 rules for C90 types). */
579 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
580 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
581 return long_long_unsigned_type_node;
583 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
584 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
586 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
587 return long_long_unsigned_type_node;
589 return long_long_integer_type_node;
592 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
593 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
594 return long_unsigned_type_node;
596 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
597 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
599 /* But preserve unsignedness from the other type,
600 since long cannot hold all the values of an unsigned int. */
601 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
602 return long_unsigned_type_node;
604 return long_integer_type_node;
607 /* Likewise, prefer long double to double even if same size. */
608 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
609 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
610 return long_double_type_node;
612 /* Otherwise prefer the unsigned one. */
614 if (TYPE_UNSIGNED (t1))
620 /* Wrapper around c_common_type that is used by c-common.c. ENUMERAL_TYPEs
621 are allowed here and are converted to their compatible integer types.
622 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
623 preferably a non-Boolean type as the common type. */
625 common_type (tree t1, tree t2)
627 if (TREE_CODE (t1) == ENUMERAL_TYPE)
628 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
629 if (TREE_CODE (t2) == ENUMERAL_TYPE)
630 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
632 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
633 if (TREE_CODE (t1) == BOOLEAN_TYPE
634 && TREE_CODE (t2) == BOOLEAN_TYPE)
635 return boolean_type_node;
637 /* If either type is BOOLEAN_TYPE, then return the other. */
638 if (TREE_CODE (t1) == BOOLEAN_TYPE)
640 if (TREE_CODE (t2) == BOOLEAN_TYPE)
643 return c_common_type (t1, t2);
646 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
647 or various other operations. Return 2 if they are compatible
648 but a warning may be needed if you use them together. */
651 comptypes (tree type1, tree type2)
657 /* Suppress errors caused by previously reported errors. */
659 if (t1 == t2 || !t1 || !t2
660 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
663 /* If either type is the internal version of sizetype, return the
665 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
666 && TYPE_ORIG_SIZE_TYPE (t1))
667 t1 = TYPE_ORIG_SIZE_TYPE (t1);
669 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
670 && TYPE_ORIG_SIZE_TYPE (t2))
671 t2 = TYPE_ORIG_SIZE_TYPE (t2);
674 /* Enumerated types are compatible with integer types, but this is
675 not transitive: two enumerated types in the same translation unit
676 are compatible with each other only if they are the same type. */
678 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
679 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
680 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
681 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
686 /* Different classes of types can't be compatible. */
688 if (TREE_CODE (t1) != TREE_CODE (t2))
691 /* Qualifiers must match. C99 6.7.3p9 */
693 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
696 /* Allow for two different type nodes which have essentially the same
697 definition. Note that we already checked for equality of the type
698 qualifiers (just above). */
700 if (TREE_CODE (t1) != ARRAY_TYPE
701 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
704 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
705 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
708 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
711 switch (TREE_CODE (t1))
714 /* Do not remove mode or aliasing information. */
715 if (TYPE_MODE (t1) != TYPE_MODE (t2)
716 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
718 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
719 ? 1 : comptypes (TREE_TYPE (t1), TREE_TYPE (t2)));
723 val = function_types_compatible_p (t1, t2);
728 tree d1 = TYPE_DOMAIN (t1);
729 tree d2 = TYPE_DOMAIN (t2);
730 bool d1_variable, d2_variable;
731 bool d1_zero, d2_zero;
734 /* Target types must match incl. qualifiers. */
735 if (TREE_TYPE (t1) != TREE_TYPE (t2)
736 && 0 == (val = comptypes (TREE_TYPE (t1), TREE_TYPE (t2))))
739 /* Sizes must match unless one is missing or variable. */
740 if (d1 == 0 || d2 == 0 || d1 == d2)
743 d1_zero = !TYPE_MAX_VALUE (d1);
744 d2_zero = !TYPE_MAX_VALUE (d2);
746 d1_variable = (!d1_zero
747 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
748 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
749 d2_variable = (!d2_zero
750 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
751 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
753 if (d1_variable || d2_variable)
755 if (d1_zero && d2_zero)
757 if (d1_zero || d2_zero
758 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
759 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
768 if (val != 1 && !same_translation_unit_p (t1, t2))
769 val = tagged_types_tu_compatible_p (t1, t2);
773 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
774 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2));
780 return attrval == 2 && val == 1 ? 2 : val;
783 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
784 ignoring their qualifiers. */
787 comp_target_types (tree ttl, tree ttr)
792 /* Do not lose qualifiers on element types of array types that are
793 pointer targets by taking their TYPE_MAIN_VARIANT. */
794 mvl = TREE_TYPE (ttl);
795 mvr = TREE_TYPE (ttr);
796 if (TREE_CODE (mvl) != ARRAY_TYPE)
797 mvl = TYPE_MAIN_VARIANT (mvl);
798 if (TREE_CODE (mvr) != ARRAY_TYPE)
799 mvr = TYPE_MAIN_VARIANT (mvr);
800 val = comptypes (mvl, mvr);
802 if (val == 2 && pedantic)
803 pedwarn ("types are not quite compatible");
807 /* Subroutines of `comptypes'. */
809 /* Determine whether two trees derive from the same translation unit.
810 If the CONTEXT chain ends in a null, that tree's context is still
811 being parsed, so if two trees have context chains ending in null,
812 they're in the same translation unit. */
814 same_translation_unit_p (tree t1, tree t2)
816 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
817 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
819 case tcc_declaration:
820 t1 = DECL_CONTEXT (t1); break;
822 t1 = TYPE_CONTEXT (t1); break;
823 case tcc_exceptional:
824 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
825 default: gcc_unreachable ();
828 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
829 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
831 case tcc_declaration:
832 t2 = DECL_CONTEXT (t2); break;
834 t2 = TYPE_CONTEXT (t2); break;
835 case tcc_exceptional:
836 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
837 default: gcc_unreachable ();
843 /* The C standard says that two structures in different translation
844 units are compatible with each other only if the types of their
845 fields are compatible (among other things). So, consider two copies
846 of this structure: */
848 struct tagged_tu_seen {
849 const struct tagged_tu_seen * next;
854 /* Can they be compatible with each other? We choose to break the
855 recursion by allowing those types to be compatible. */
857 static const struct tagged_tu_seen * tagged_tu_seen_base;
859 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
860 compatible. If the two types are not the same (which has been
861 checked earlier), this can only happen when multiple translation
862 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
866 tagged_types_tu_compatible_p (tree t1, tree t2)
869 bool needs_warning = false;
871 /* We have to verify that the tags of the types are the same. This
872 is harder than it looks because this may be a typedef, so we have
873 to go look at the original type. It may even be a typedef of a
875 In the case of compiler-created builtin structs the TYPE_DECL
876 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
877 while (TYPE_NAME (t1)
878 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
879 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
880 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
882 while (TYPE_NAME (t2)
883 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
884 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
885 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
887 /* C90 didn't have the requirement that the two tags be the same. */
888 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
891 /* C90 didn't say what happened if one or both of the types were
892 incomplete; we choose to follow C99 rules here, which is that they
894 if (TYPE_SIZE (t1) == NULL
895 || TYPE_SIZE (t2) == NULL)
899 const struct tagged_tu_seen * tts_i;
900 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
901 if (tts_i->t1 == t1 && tts_i->t2 == t2)
905 switch (TREE_CODE (t1))
910 /* Speed up the case where the type values are in the same order. */
911 tree tv1 = TYPE_VALUES (t1);
912 tree tv2 = TYPE_VALUES (t2);
917 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
919 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
921 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
925 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
927 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
930 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
933 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
935 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
937 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
945 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
948 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
951 struct tagged_tu_seen tts;
953 tts.next = tagged_tu_seen_base;
956 tagged_tu_seen_base = &tts;
958 if (DECL_NAME (s1) != NULL)
959 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
960 if (DECL_NAME (s1) == DECL_NAME (s2))
963 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
967 needs_warning = true;
969 if (TREE_CODE (s1) == FIELD_DECL
970 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
971 DECL_FIELD_BIT_OFFSET (s2)) != 1)
977 tagged_tu_seen_base = tts.next;
981 return needs_warning ? 2 : 1;
986 struct tagged_tu_seen tts;
988 tts.next = tagged_tu_seen_base;
991 tagged_tu_seen_base = &tts;
993 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
995 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
998 if (TREE_CODE (s1) != TREE_CODE (s2)
999 || DECL_NAME (s1) != DECL_NAME (s2))
1001 result = comptypes (TREE_TYPE (s1), TREE_TYPE (s2));
1005 needs_warning = true;
1007 if (TREE_CODE (s1) == FIELD_DECL
1008 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1009 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1012 tagged_tu_seen_base = tts.next;
1015 return needs_warning ? 2 : 1;
1023 /* Return 1 if two function types F1 and F2 are compatible.
1024 If either type specifies no argument types,
1025 the other must specify a fixed number of self-promoting arg types.
1026 Otherwise, if one type specifies only the number of arguments,
1027 the other must specify that number of self-promoting arg types.
1028 Otherwise, the argument types must match. */
1031 function_types_compatible_p (tree f1, tree f2)
1034 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1039 ret1 = TREE_TYPE (f1);
1040 ret2 = TREE_TYPE (f2);
1042 /* 'volatile' qualifiers on a function's return type used to mean
1043 the function is noreturn. */
1044 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1045 pedwarn ("function return types not compatible due to %<volatile%>");
1046 if (TYPE_VOLATILE (ret1))
1047 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1048 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1049 if (TYPE_VOLATILE (ret2))
1050 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1051 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1052 val = comptypes (ret1, ret2);
1056 args1 = TYPE_ARG_TYPES (f1);
1057 args2 = TYPE_ARG_TYPES (f2);
1059 /* An unspecified parmlist matches any specified parmlist
1060 whose argument types don't need default promotions. */
1064 if (!self_promoting_args_p (args2))
1066 /* If one of these types comes from a non-prototype fn definition,
1067 compare that with the other type's arglist.
1068 If they don't match, ask for a warning (0, but no error). */
1069 if (TYPE_ACTUAL_ARG_TYPES (f1)
1070 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1076 if (!self_promoting_args_p (args1))
1078 if (TYPE_ACTUAL_ARG_TYPES (f2)
1079 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1084 /* Both types have argument lists: compare them and propagate results. */
1085 val1 = type_lists_compatible_p (args1, args2);
1086 return val1 != 1 ? val1 : val;
1089 /* Check two lists of types for compatibility,
1090 returning 0 for incompatible, 1 for compatible,
1091 or 2 for compatible with warning. */
1094 type_lists_compatible_p (tree args1, tree args2)
1096 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1102 tree a1, mv1, a2, mv2;
1103 if (args1 == 0 && args2 == 0)
1105 /* If one list is shorter than the other,
1106 they fail to match. */
1107 if (args1 == 0 || args2 == 0)
1109 mv1 = a1 = TREE_VALUE (args1);
1110 mv2 = a2 = TREE_VALUE (args2);
1111 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1112 mv1 = TYPE_MAIN_VARIANT (mv1);
1113 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1114 mv2 = TYPE_MAIN_VARIANT (mv2);
1115 /* A null pointer instead of a type
1116 means there is supposed to be an argument
1117 but nothing is specified about what type it has.
1118 So match anything that self-promotes. */
1121 if (c_type_promotes_to (a2) != a2)
1126 if (c_type_promotes_to (a1) != a1)
1129 /* If one of the lists has an error marker, ignore this arg. */
1130 else if (TREE_CODE (a1) == ERROR_MARK
1131 || TREE_CODE (a2) == ERROR_MARK)
1133 else if (!(newval = comptypes (mv1, mv2)))
1135 /* Allow wait (union {union wait *u; int *i} *)
1136 and wait (union wait *) to be compatible. */
1137 if (TREE_CODE (a1) == UNION_TYPE
1138 && (TYPE_NAME (a1) == 0
1139 || TYPE_TRANSPARENT_UNION (a1))
1140 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1141 && tree_int_cst_equal (TYPE_SIZE (a1),
1145 for (memb = TYPE_FIELDS (a1);
1146 memb; memb = TREE_CHAIN (memb))
1148 tree mv3 = TREE_TYPE (memb);
1149 if (mv3 && mv3 != error_mark_node
1150 && TREE_CODE (mv3) != ARRAY_TYPE)
1151 mv3 = TYPE_MAIN_VARIANT (mv3);
1152 if (comptypes (mv3, mv2))
1158 else if (TREE_CODE (a2) == UNION_TYPE
1159 && (TYPE_NAME (a2) == 0
1160 || TYPE_TRANSPARENT_UNION (a2))
1161 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1162 && tree_int_cst_equal (TYPE_SIZE (a2),
1166 for (memb = TYPE_FIELDS (a2);
1167 memb; memb = TREE_CHAIN (memb))
1169 tree mv3 = TREE_TYPE (memb);
1170 if (mv3 && mv3 != error_mark_node
1171 && TREE_CODE (mv3) != ARRAY_TYPE)
1172 mv3 = TYPE_MAIN_VARIANT (mv3);
1173 if (comptypes (mv3, mv1))
1183 /* comptypes said ok, but record if it said to warn. */
1187 args1 = TREE_CHAIN (args1);
1188 args2 = TREE_CHAIN (args2);
1192 /* Compute the size to increment a pointer by. */
1195 c_size_in_bytes (tree type)
1197 enum tree_code code = TREE_CODE (type);
1199 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1200 return size_one_node;
1202 if (!COMPLETE_OR_VOID_TYPE_P (type))
1204 error ("arithmetic on pointer to an incomplete type");
1205 return size_one_node;
1208 /* Convert in case a char is more than one unit. */
1209 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1210 size_int (TYPE_PRECISION (char_type_node)
1214 /* Return either DECL or its known constant value (if it has one). */
1217 decl_constant_value (tree decl)
1219 if (/* Don't change a variable array bound or initial value to a constant
1220 in a place where a variable is invalid. Note that DECL_INITIAL
1221 isn't valid for a PARM_DECL. */
1222 current_function_decl != 0
1223 && TREE_CODE (decl) != PARM_DECL
1224 && !TREE_THIS_VOLATILE (decl)
1225 && TREE_READONLY (decl)
1226 && DECL_INITIAL (decl) != 0
1227 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1228 /* This is invalid if initial value is not constant.
1229 If it has either a function call, a memory reference,
1230 or a variable, then re-evaluating it could give different results. */
1231 && TREE_CONSTANT (DECL_INITIAL (decl))
1232 /* Check for cases where this is sub-optimal, even though valid. */
1233 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1234 return DECL_INITIAL (decl);
1238 /* Return either DECL or its known constant value (if it has one), but
1239 return DECL if pedantic or DECL has mode BLKmode. This is for
1240 bug-compatibility with the old behavior of decl_constant_value
1241 (before GCC 3.0); every use of this function is a bug and it should
1242 be removed before GCC 3.1. It is not appropriate to use pedantic
1243 in a way that affects optimization, and BLKmode is probably not the
1244 right test for avoiding misoptimizations either. */
1247 decl_constant_value_for_broken_optimization (tree decl)
1251 if (pedantic || DECL_MODE (decl) == BLKmode)
1254 ret = decl_constant_value (decl);
1255 /* Avoid unwanted tree sharing between the initializer and current
1256 function's body where the tree can be modified e.g. by the
1258 if (ret != decl && TREE_STATIC (decl))
1259 ret = unshare_expr (ret);
1264 /* Perform the default conversion of arrays and functions to pointers.
1265 Return the result of converting EXP. For any other expression, just
1269 default_function_array_conversion (tree exp)
1272 tree type = TREE_TYPE (exp);
1273 enum tree_code code = TREE_CODE (type);
1276 /* Strip NON_LVALUE_EXPRs and no-op conversions, since we aren't using as
1279 Do not use STRIP_NOPS here! It will remove conversions from pointer
1280 to integer and cause infinite recursion. */
1282 while (TREE_CODE (exp) == NON_LVALUE_EXPR
1283 || (TREE_CODE (exp) == NOP_EXPR
1284 && TREE_TYPE (TREE_OPERAND (exp, 0)) == TREE_TYPE (exp)))
1286 if (TREE_CODE (exp) == NON_LVALUE_EXPR)
1288 exp = TREE_OPERAND (exp, 0);
1291 if (TREE_NO_WARNING (orig_exp))
1292 TREE_NO_WARNING (exp) = 1;
1294 if (code == FUNCTION_TYPE)
1296 return build_unary_op (ADDR_EXPR, exp, 0);
1298 if (code == ARRAY_TYPE)
1301 tree restype = TREE_TYPE (type);
1307 if (REFERENCE_CLASS_P (exp) || DECL_P (exp))
1309 constp = TREE_READONLY (exp);
1310 volatilep = TREE_THIS_VOLATILE (exp);
1313 if (TYPE_QUALS (type) || constp || volatilep)
1315 = c_build_qualified_type (restype,
1317 | (constp * TYPE_QUAL_CONST)
1318 | (volatilep * TYPE_QUAL_VOLATILE));
1320 if (TREE_CODE (exp) == INDIRECT_REF)
1321 return convert (build_pointer_type (restype),
1322 TREE_OPERAND (exp, 0));
1324 if (TREE_CODE (exp) == COMPOUND_EXPR)
1326 tree op1 = default_conversion (TREE_OPERAND (exp, 1));
1327 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1328 TREE_OPERAND (exp, 0), op1);
1331 lvalue_array_p = !not_lvalue && lvalue_p (exp);
1332 if (!flag_isoc99 && !lvalue_array_p)
1334 /* Before C99, non-lvalue arrays do not decay to pointers.
1335 Normally, using such an array would be invalid; but it can
1336 be used correctly inside sizeof or as a statement expression.
1337 Thus, do not give an error here; an error will result later. */
1341 ptrtype = build_pointer_type (restype);
1343 if (TREE_CODE (exp) == VAR_DECL)
1345 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1346 ADDR_EXPR because it's the best way of representing what
1347 happens in C when we take the address of an array and place
1348 it in a pointer to the element type. */
1349 adr = build1 (ADDR_EXPR, ptrtype, exp);
1350 if (!c_mark_addressable (exp))
1351 return error_mark_node;
1352 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1355 /* This way is better for a COMPONENT_REF since it can
1356 simplify the offset for a component. */
1357 adr = build_unary_op (ADDR_EXPR, exp, 1);
1358 return convert (ptrtype, adr);
1364 /* EXP is an expression of integer type. Apply the integer promotions
1365 to it and return the promoted value. */
1368 perform_integral_promotions (tree exp)
1370 tree type = TREE_TYPE (exp);
1371 enum tree_code code = TREE_CODE (type);
1373 gcc_assert (INTEGRAL_TYPE_P (type));
1375 /* Normally convert enums to int,
1376 but convert wide enums to something wider. */
1377 if (code == ENUMERAL_TYPE)
1379 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1380 TYPE_PRECISION (integer_type_node)),
1381 ((TYPE_PRECISION (type)
1382 >= TYPE_PRECISION (integer_type_node))
1383 && TYPE_UNSIGNED (type)));
1385 return convert (type, exp);
1388 /* ??? This should no longer be needed now bit-fields have their
1390 if (TREE_CODE (exp) == COMPONENT_REF
1391 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1392 /* If it's thinner than an int, promote it like a
1393 c_promoting_integer_type_p, otherwise leave it alone. */
1394 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1395 TYPE_PRECISION (integer_type_node)))
1396 return convert (integer_type_node, exp);
1398 if (c_promoting_integer_type_p (type))
1400 /* Preserve unsignedness if not really getting any wider. */
1401 if (TYPE_UNSIGNED (type)
1402 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1403 return convert (unsigned_type_node, exp);
1405 return convert (integer_type_node, exp);
1412 /* Perform default promotions for C data used in expressions.
1413 Arrays and functions are converted to pointers;
1414 enumeral types or short or char, to int.
1415 In addition, manifest constants symbols are replaced by their values. */
1418 default_conversion (tree exp)
1421 tree type = TREE_TYPE (exp);
1422 enum tree_code code = TREE_CODE (type);
1424 if (code == FUNCTION_TYPE || code == ARRAY_TYPE)
1425 return default_function_array_conversion (exp);
1427 /* Constants can be used directly unless they're not loadable. */
1428 if (TREE_CODE (exp) == CONST_DECL)
1429 exp = DECL_INITIAL (exp);
1431 /* Replace a nonvolatile const static variable with its value unless
1432 it is an array, in which case we must be sure that taking the
1433 address of the array produces consistent results. */
1434 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1436 exp = decl_constant_value_for_broken_optimization (exp);
1437 type = TREE_TYPE (exp);
1440 /* Strip no-op conversions. */
1442 STRIP_TYPE_NOPS (exp);
1444 if (TREE_NO_WARNING (orig_exp))
1445 TREE_NO_WARNING (exp) = 1;
1447 if (INTEGRAL_TYPE_P (type))
1448 return perform_integral_promotions (exp);
1450 if (code == VOID_TYPE)
1452 error ("void value not ignored as it ought to be");
1453 return error_mark_node;
1458 /* Look up COMPONENT in a structure or union DECL.
1460 If the component name is not found, returns NULL_TREE. Otherwise,
1461 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1462 stepping down the chain to the component, which is in the last
1463 TREE_VALUE of the list. Normally the list is of length one, but if
1464 the component is embedded within (nested) anonymous structures or
1465 unions, the list steps down the chain to the component. */
1468 lookup_field (tree decl, tree component)
1470 tree type = TREE_TYPE (decl);
1473 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1474 to the field elements. Use a binary search on this array to quickly
1475 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1476 will always be set for structures which have many elements. */
1478 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1481 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1483 field = TYPE_FIELDS (type);
1485 top = TYPE_LANG_SPECIFIC (type)->s->len;
1486 while (top - bot > 1)
1488 half = (top - bot + 1) >> 1;
1489 field = field_array[bot+half];
1491 if (DECL_NAME (field) == NULL_TREE)
1493 /* Step through all anon unions in linear fashion. */
1494 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1496 field = field_array[bot++];
1497 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1498 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1500 tree anon = lookup_field (field, component);
1503 return tree_cons (NULL_TREE, field, anon);
1507 /* Entire record is only anon unions. */
1511 /* Restart the binary search, with new lower bound. */
1515 if (DECL_NAME (field) == component)
1517 if (DECL_NAME (field) < component)
1523 if (DECL_NAME (field_array[bot]) == component)
1524 field = field_array[bot];
1525 else if (DECL_NAME (field) != component)
1530 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1532 if (DECL_NAME (field) == NULL_TREE
1533 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1534 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1536 tree anon = lookup_field (field, component);
1539 return tree_cons (NULL_TREE, field, anon);
1542 if (DECL_NAME (field) == component)
1546 if (field == NULL_TREE)
1550 return tree_cons (NULL_TREE, field, NULL_TREE);
1553 /* Make an expression to refer to the COMPONENT field of
1554 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1557 build_component_ref (tree datum, tree component)
1559 tree type = TREE_TYPE (datum);
1560 enum tree_code code = TREE_CODE (type);
1564 if (!objc_is_public (datum, component))
1565 return error_mark_node;
1567 /* See if there is a field or component with name COMPONENT. */
1569 if (code == RECORD_TYPE || code == UNION_TYPE)
1571 if (!COMPLETE_TYPE_P (type))
1573 c_incomplete_type_error (NULL_TREE, type);
1574 return error_mark_node;
1577 field = lookup_field (datum, component);
1581 error ("%qT has no member named %qE", type, component);
1582 return error_mark_node;
1585 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1586 This might be better solved in future the way the C++ front
1587 end does it - by giving the anonymous entities each a
1588 separate name and type, and then have build_component_ref
1589 recursively call itself. We can't do that here. */
1592 tree subdatum = TREE_VALUE (field);
1594 if (TREE_TYPE (subdatum) == error_mark_node)
1595 return error_mark_node;
1597 ref = build3 (COMPONENT_REF, TREE_TYPE (subdatum), datum, subdatum,
1599 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1600 TREE_READONLY (ref) = 1;
1601 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1602 TREE_THIS_VOLATILE (ref) = 1;
1604 if (TREE_DEPRECATED (subdatum))
1605 warn_deprecated_use (subdatum);
1609 field = TREE_CHAIN (field);
1615 else if (code != ERROR_MARK)
1616 error ("request for member %qE in something not a structure or union",
1619 return error_mark_node;
1622 /* Given an expression PTR for a pointer, return an expression
1623 for the value pointed to.
1624 ERRORSTRING is the name of the operator to appear in error messages. */
1627 build_indirect_ref (tree ptr, const char *errorstring)
1629 tree pointer = default_conversion (ptr);
1630 tree type = TREE_TYPE (pointer);
1632 if (TREE_CODE (type) == POINTER_TYPE)
1634 if (TREE_CODE (pointer) == ADDR_EXPR
1635 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1636 == TREE_TYPE (type)))
1637 return TREE_OPERAND (pointer, 0);
1640 tree t = TREE_TYPE (type);
1643 ref = build1 (INDIRECT_REF, t, pointer);
1645 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1647 error ("dereferencing pointer to incomplete type");
1648 return error_mark_node;
1650 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1651 warning (0, "dereferencing %<void *%> pointer");
1653 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1654 so that we get the proper error message if the result is used
1655 to assign to. Also, &* is supposed to be a no-op.
1656 And ANSI C seems to specify that the type of the result
1657 should be the const type. */
1658 /* A de-reference of a pointer to const is not a const. It is valid
1659 to change it via some other pointer. */
1660 TREE_READONLY (ref) = TYPE_READONLY (t);
1661 TREE_SIDE_EFFECTS (ref)
1662 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1663 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1667 else if (TREE_CODE (pointer) != ERROR_MARK)
1668 error ("invalid type argument of %qs", errorstring);
1669 return error_mark_node;
1672 /* This handles expressions of the form "a[i]", which denotes
1675 This is logically equivalent in C to *(a+i), but we may do it differently.
1676 If A is a variable or a member, we generate a primitive ARRAY_REF.
1677 This avoids forcing the array out of registers, and can work on
1678 arrays that are not lvalues (for example, members of structures returned
1682 build_array_ref (tree array, tree index)
1684 bool swapped = false;
1685 if (TREE_TYPE (array) == error_mark_node
1686 || TREE_TYPE (index) == error_mark_node)
1687 return error_mark_node;
1689 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1690 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1693 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1694 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1696 error ("subscripted value is neither array nor pointer");
1697 return error_mark_node;
1705 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1707 error ("array subscript is not an integer");
1708 return error_mark_node;
1711 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1713 error ("subscripted value is pointer to function");
1714 return error_mark_node;
1717 /* Subscripting with type char is likely to lose on a machine where
1718 chars are signed. So warn on any machine, but optionally. Don't
1719 warn for unsigned char since that type is safe. Don't warn for
1720 signed char because anyone who uses that must have done so
1721 deliberately. ??? Existing practice has also been to warn only
1722 when the char index is syntactically the index, not for
1724 if (warn_char_subscripts && !swapped
1725 && TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node)
1726 warning (0, "array subscript has type %<char%>");
1728 /* Apply default promotions *after* noticing character types. */
1729 index = default_conversion (index);
1731 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1733 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1737 /* An array that is indexed by a non-constant
1738 cannot be stored in a register; we must be able to do
1739 address arithmetic on its address.
1740 Likewise an array of elements of variable size. */
1741 if (TREE_CODE (index) != INTEGER_CST
1742 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1743 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1745 if (!c_mark_addressable (array))
1746 return error_mark_node;
1748 /* An array that is indexed by a constant value which is not within
1749 the array bounds cannot be stored in a register either; because we
1750 would get a crash in store_bit_field/extract_bit_field when trying
1751 to access a non-existent part of the register. */
1752 if (TREE_CODE (index) == INTEGER_CST
1753 && TYPE_DOMAIN (TREE_TYPE (array))
1754 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1756 if (!c_mark_addressable (array))
1757 return error_mark_node;
1763 while (TREE_CODE (foo) == COMPONENT_REF)
1764 foo = TREE_OPERAND (foo, 0);
1765 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
1766 pedwarn ("ISO C forbids subscripting %<register%> array");
1767 else if (!flag_isoc99 && !lvalue_p (foo))
1768 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
1771 type = TREE_TYPE (TREE_TYPE (array));
1772 if (TREE_CODE (type) != ARRAY_TYPE)
1773 type = TYPE_MAIN_VARIANT (type);
1774 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
1775 /* Array ref is const/volatile if the array elements are
1776 or if the array is. */
1777 TREE_READONLY (rval)
1778 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
1779 | TREE_READONLY (array));
1780 TREE_SIDE_EFFECTS (rval)
1781 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1782 | TREE_SIDE_EFFECTS (array));
1783 TREE_THIS_VOLATILE (rval)
1784 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
1785 /* This was added by rms on 16 Nov 91.
1786 It fixes vol struct foo *a; a->elts[1]
1787 in an inline function.
1788 Hope it doesn't break something else. */
1789 | TREE_THIS_VOLATILE (array));
1790 return require_complete_type (fold (rval));
1794 tree ar = default_conversion (array);
1796 if (ar == error_mark_node)
1799 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
1800 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
1802 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
1807 /* Build an external reference to identifier ID. FUN indicates
1808 whether this will be used for a function call. LOC is the source
1809 location of the identifier. */
1811 build_external_ref (tree id, int fun, location_t loc)
1814 tree decl = lookup_name (id);
1816 /* In Objective-C, an instance variable (ivar) may be preferred to
1817 whatever lookup_name() found. */
1818 decl = objc_lookup_ivar (decl, id);
1820 if (decl && decl != error_mark_node)
1823 /* Implicit function declaration. */
1824 ref = implicitly_declare (id);
1825 else if (decl == error_mark_node)
1826 /* Don't complain about something that's already been
1827 complained about. */
1828 return error_mark_node;
1831 undeclared_variable (id, loc);
1832 return error_mark_node;
1835 if (TREE_TYPE (ref) == error_mark_node)
1836 return error_mark_node;
1838 if (TREE_DEPRECATED (ref))
1839 warn_deprecated_use (ref);
1841 if (!skip_evaluation)
1842 assemble_external (ref);
1843 TREE_USED (ref) = 1;
1845 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
1847 if (!in_sizeof && !in_typeof)
1848 C_DECL_USED (ref) = 1;
1849 else if (DECL_INITIAL (ref) == 0
1850 && DECL_EXTERNAL (ref)
1851 && !TREE_PUBLIC (ref))
1852 record_maybe_used_decl (ref);
1855 if (TREE_CODE (ref) == CONST_DECL)
1857 ref = DECL_INITIAL (ref);
1858 TREE_CONSTANT (ref) = 1;
1859 TREE_INVARIANT (ref) = 1;
1861 else if (current_function_decl != 0
1862 && !DECL_FILE_SCOPE_P (current_function_decl)
1863 && (TREE_CODE (ref) == VAR_DECL
1864 || TREE_CODE (ref) == PARM_DECL
1865 || TREE_CODE (ref) == FUNCTION_DECL))
1867 tree context = decl_function_context (ref);
1869 if (context != 0 && context != current_function_decl)
1870 DECL_NONLOCAL (ref) = 1;
1876 /* Record details of decls possibly used inside sizeof or typeof. */
1877 struct maybe_used_decl
1881 /* The level seen at (in_sizeof + in_typeof). */
1883 /* The next one at this level or above, or NULL. */
1884 struct maybe_used_decl *next;
1887 static struct maybe_used_decl *maybe_used_decls;
1889 /* Record that DECL, an undefined static function reference seen
1890 inside sizeof or typeof, might be used if the operand of sizeof is
1891 a VLA type or the operand of typeof is a variably modified
1895 record_maybe_used_decl (tree decl)
1897 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
1899 t->level = in_sizeof + in_typeof;
1900 t->next = maybe_used_decls;
1901 maybe_used_decls = t;
1904 /* Pop the stack of decls possibly used inside sizeof or typeof. If
1905 USED is false, just discard them. If it is true, mark them used
1906 (if no longer inside sizeof or typeof) or move them to the next
1907 level up (if still inside sizeof or typeof). */
1910 pop_maybe_used (bool used)
1912 struct maybe_used_decl *p = maybe_used_decls;
1913 int cur_level = in_sizeof + in_typeof;
1914 while (p && p->level > cur_level)
1919 C_DECL_USED (p->decl) = 1;
1921 p->level = cur_level;
1925 if (!used || cur_level == 0)
1926 maybe_used_decls = p;
1929 /* Return the result of sizeof applied to EXPR. */
1932 c_expr_sizeof_expr (struct c_expr expr)
1935 if (expr.value == error_mark_node)
1937 ret.value = error_mark_node;
1938 ret.original_code = ERROR_MARK;
1939 pop_maybe_used (false);
1943 ret.value = c_sizeof (TREE_TYPE (expr.value));
1944 ret.original_code = ERROR_MARK;
1945 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
1950 /* Return the result of sizeof applied to T, a structure for the type
1951 name passed to sizeof (rather than the type itself). */
1954 c_expr_sizeof_type (struct c_type_name *t)
1958 type = groktypename (t);
1959 ret.value = c_sizeof (type);
1960 ret.original_code = ERROR_MARK;
1961 pop_maybe_used (C_TYPE_VARIABLE_SIZE (type));
1965 /* Build a function call to function FUNCTION with parameters PARAMS.
1966 PARAMS is a list--a chain of TREE_LIST nodes--in which the
1967 TREE_VALUE of each node is a parameter-expression.
1968 FUNCTION's data type may be a function type or a pointer-to-function. */
1971 build_function_call (tree function, tree params)
1973 tree fntype, fundecl = 0;
1974 tree coerced_params;
1975 tree name = NULL_TREE, result;
1978 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
1979 STRIP_TYPE_NOPS (function);
1981 /* Convert anything with function type to a pointer-to-function. */
1982 if (TREE_CODE (function) == FUNCTION_DECL)
1984 /* Implement type-directed function overloading for builtins.
1985 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
1986 handle all the type checking. The result is a complete expression
1987 that implements this function call. */
1988 tem = resolve_overloaded_builtin (function, params);
1992 name = DECL_NAME (function);
1994 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
1995 (because calling an inline function does not mean the function
1996 needs to be separately compiled). */
1997 fntype = build_type_variant (TREE_TYPE (function),
1998 TREE_READONLY (function),
1999 TREE_THIS_VOLATILE (function));
2001 function = build1 (ADDR_EXPR, build_pointer_type (fntype), function);
2004 function = default_conversion (function);
2006 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2007 expressions, like those used for ObjC messenger dispatches. */
2008 function = objc_rewrite_function_call (function, params);
2010 fntype = TREE_TYPE (function);
2012 if (TREE_CODE (fntype) == ERROR_MARK)
2013 return error_mark_node;
2015 if (!(TREE_CODE (fntype) == POINTER_TYPE
2016 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2018 error ("called object %qE is not a function", function);
2019 return error_mark_node;
2022 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2023 current_function_returns_abnormally = 1;
2025 /* fntype now gets the type of function pointed to. */
2026 fntype = TREE_TYPE (fntype);
2028 /* Check that the function is called through a compatible prototype.
2029 If it is not, replace the call by a trap, wrapped up in a compound
2030 expression if necessary. This has the nice side-effect to prevent
2031 the tree-inliner from generating invalid assignment trees which may
2032 blow up in the RTL expander later. */
2033 if (TREE_CODE (function) == NOP_EXPR
2034 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2035 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2036 && !comptypes (fntype, TREE_TYPE (tem)))
2038 tree return_type = TREE_TYPE (fntype);
2039 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2042 /* This situation leads to run-time undefined behavior. We can't,
2043 therefore, simply error unless we can prove that all possible
2044 executions of the program must execute the code. */
2045 warning (0, "function called through a non-compatible type");
2047 /* We can, however, treat "undefined" any way we please.
2048 Call abort to encourage the user to fix the program. */
2049 inform ("if this code is reached, the program will abort");
2051 if (VOID_TYPE_P (return_type))
2057 if (AGGREGATE_TYPE_P (return_type))
2058 rhs = build_compound_literal (return_type,
2059 build_constructor (return_type,
2062 rhs = fold (build1 (NOP_EXPR, return_type, integer_zero_node));
2064 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2068 /* Convert the parameters to the types declared in the
2069 function prototype, or apply default promotions. */
2072 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2074 if (coerced_params == error_mark_node)
2075 return error_mark_node;
2077 /* Check that the arguments to the function are valid. */
2079 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params);
2081 result = build3 (CALL_EXPR, TREE_TYPE (fntype),
2082 function, coerced_params, NULL_TREE);
2083 TREE_SIDE_EFFECTS (result) = 1;
2085 if (require_constant_value)
2087 result = fold_initializer (result);
2089 if (TREE_CONSTANT (result)
2090 && (name == NULL_TREE
2091 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2092 pedwarn_init ("initializer element is not constant");
2095 result = fold (result);
2097 if (VOID_TYPE_P (TREE_TYPE (result)))
2099 return require_complete_type (result);
2102 /* Convert the argument expressions in the list VALUES
2103 to the types in the list TYPELIST. The result is a list of converted
2104 argument expressions, unless there are too few arguments in which
2105 case it is error_mark_node.
2107 If TYPELIST is exhausted, or when an element has NULL as its type,
2108 perform the default conversions.
2110 PARMLIST is the chain of parm decls for the function being called.
2111 It may be 0, if that info is not available.
2112 It is used only for generating error messages.
2114 FUNCTION is a tree for the called function. It is used only for
2115 error messages, where it is formatted with %qE.
2117 This is also where warnings about wrong number of args are generated.
2119 Both VALUES and the returned value are chains of TREE_LIST nodes
2120 with the elements of the list in the TREE_VALUE slots of those nodes. */
2123 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2125 tree typetail, valtail;
2130 /* Change pointer to function to the function itself for
2132 if (TREE_CODE (function) == ADDR_EXPR
2133 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2134 function = TREE_OPERAND (function, 0);
2136 /* Handle an ObjC selector specially for diagnostics. */
2137 selector = objc_message_selector ();
2139 /* Scan the given expressions and types, producing individual
2140 converted arguments and pushing them on RESULT in reverse order. */
2142 for (valtail = values, typetail = typelist, parmnum = 0;
2144 valtail = TREE_CHAIN (valtail), parmnum++)
2146 tree type = typetail ? TREE_VALUE (typetail) : 0;
2147 tree val = TREE_VALUE (valtail);
2148 tree rname = function;
2149 int argnum = parmnum + 1;
2150 const char *invalid_func_diag;
2152 if (type == void_type_node)
2154 error ("too many arguments to function %qE", function);
2158 if (selector && argnum > 2)
2164 STRIP_TYPE_NOPS (val);
2166 val = default_function_array_conversion (val);
2168 val = require_complete_type (val);
2172 /* Formal parm type is specified by a function prototype. */
2175 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2177 error ("type of formal parameter %d is incomplete", parmnum + 1);
2182 /* Optionally warn about conversions that
2183 differ from the default conversions. */
2184 if (warn_conversion || warn_traditional)
2186 unsigned int formal_prec = TYPE_PRECISION (type);
2188 if (INTEGRAL_TYPE_P (type)
2189 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2190 warning (0, "passing argument %d of %qE as integer "
2191 "rather than floating due to prototype",
2193 if (INTEGRAL_TYPE_P (type)
2194 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2195 warning (0, "passing argument %d of %qE as integer "
2196 "rather than complex due to prototype",
2198 else if (TREE_CODE (type) == COMPLEX_TYPE
2199 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2200 warning (0, "passing argument %d of %qE as complex "
2201 "rather than floating due to prototype",
2203 else if (TREE_CODE (type) == REAL_TYPE
2204 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2205 warning (0, "passing argument %d of %qE as floating "
2206 "rather than integer due to prototype",
2208 else if (TREE_CODE (type) == COMPLEX_TYPE
2209 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2210 warning (0, "passing argument %d of %qE as complex "
2211 "rather than integer due to prototype",
2213 else if (TREE_CODE (type) == REAL_TYPE
2214 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2215 warning (0, "passing argument %d of %qE as floating "
2216 "rather than complex due to prototype",
2218 /* ??? At some point, messages should be written about
2219 conversions between complex types, but that's too messy
2221 else if (TREE_CODE (type) == REAL_TYPE
2222 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2224 /* Warn if any argument is passed as `float',
2225 since without a prototype it would be `double'. */
2226 if (formal_prec == TYPE_PRECISION (float_type_node))
2227 warning (0, "passing argument %d of %qE as %<float%> "
2228 "rather than %<double%> due to prototype",
2231 /* Detect integer changing in width or signedness.
2232 These warnings are only activated with
2233 -Wconversion, not with -Wtraditional. */
2234 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2235 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2237 tree would_have_been = default_conversion (val);
2238 tree type1 = TREE_TYPE (would_have_been);
2240 if (TREE_CODE (type) == ENUMERAL_TYPE
2241 && (TYPE_MAIN_VARIANT (type)
2242 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2243 /* No warning if function asks for enum
2244 and the actual arg is that enum type. */
2246 else if (formal_prec != TYPE_PRECISION (type1))
2247 warning (0, "passing argument %d of %qE with different "
2248 "width due to prototype", argnum, rname);
2249 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2251 /* Don't complain if the formal parameter type
2252 is an enum, because we can't tell now whether
2253 the value was an enum--even the same enum. */
2254 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2256 else if (TREE_CODE (val) == INTEGER_CST
2257 && int_fits_type_p (val, type))
2258 /* Change in signedness doesn't matter
2259 if a constant value is unaffected. */
2261 /* If the value is extended from a narrower
2262 unsigned type, it doesn't matter whether we
2263 pass it as signed or unsigned; the value
2264 certainly is the same either way. */
2265 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2266 && TYPE_UNSIGNED (TREE_TYPE (val)))
2268 else if (TYPE_UNSIGNED (type))
2269 warning (0, "passing argument %d of %qE as unsigned "
2270 "due to prototype", argnum, rname);
2272 warning (0, "passing argument %d of %qE as signed "
2273 "due to prototype", argnum, rname);
2277 parmval = convert_for_assignment (type, val, ic_argpass,
2281 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2282 && INTEGRAL_TYPE_P (type)
2283 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2284 parmval = default_conversion (parmval);
2286 result = tree_cons (NULL_TREE, parmval, result);
2288 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2289 && (TYPE_PRECISION (TREE_TYPE (val))
2290 < TYPE_PRECISION (double_type_node)))
2291 /* Convert `float' to `double'. */
2292 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2293 else if ((invalid_func_diag =
2294 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2296 error (invalid_func_diag);
2297 return error_mark_node;
2300 /* Convert `short' and `char' to full-size `int'. */
2301 result = tree_cons (NULL_TREE, default_conversion (val), result);
2304 typetail = TREE_CHAIN (typetail);
2307 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2309 error ("too few arguments to function %qE", function);
2310 return error_mark_node;
2313 return nreverse (result);
2316 /* This is the entry point used by the parser to build unary operators
2317 in the input. CODE, a tree_code, specifies the unary operator, and
2318 ARG is the operand. For unary plus, the C parser currently uses
2319 CONVERT_EXPR for code. */
2322 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2324 struct c_expr result;
2326 result.original_code = ERROR_MARK;
2327 result.value = build_unary_op (code, arg.value, 0);
2328 overflow_warning (result.value);
2332 /* This is the entry point used by the parser to build binary operators
2333 in the input. CODE, a tree_code, specifies the binary operator, and
2334 ARG1 and ARG2 are the operands. In addition to constructing the
2335 expression, we check for operands that were written with other binary
2336 operators in a way that is likely to confuse the user. */
2339 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2342 struct c_expr result;
2344 enum tree_code code1 = arg1.original_code;
2345 enum tree_code code2 = arg2.original_code;
2347 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2348 result.original_code = code;
2350 if (TREE_CODE (result.value) == ERROR_MARK)
2353 /* Check for cases such as x+y<<z which users are likely
2355 if (warn_parentheses)
2357 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
2359 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2360 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2361 warning (0, "suggest parentheses around + or - inside shift");
2364 if (code == TRUTH_ORIF_EXPR)
2366 if (code1 == TRUTH_ANDIF_EXPR
2367 || code2 == TRUTH_ANDIF_EXPR)
2368 warning (0, "suggest parentheses around && within ||");
2371 if (code == BIT_IOR_EXPR)
2373 if (code1 == BIT_AND_EXPR || code1 == BIT_XOR_EXPR
2374 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2375 || code2 == BIT_AND_EXPR || code2 == BIT_XOR_EXPR
2376 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2377 warning (0, "suggest parentheses around arithmetic in operand of |");
2378 /* Check cases like x|y==z */
2379 if (TREE_CODE_CLASS (code1) == tcc_comparison
2380 || TREE_CODE_CLASS (code2) == tcc_comparison)
2381 warning (0, "suggest parentheses around comparison in operand of |");
2384 if (code == BIT_XOR_EXPR)
2386 if (code1 == BIT_AND_EXPR
2387 || code1 == PLUS_EXPR || code1 == MINUS_EXPR
2388 || code2 == BIT_AND_EXPR
2389 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2390 warning (0, "suggest parentheses around arithmetic in operand of ^");
2391 /* Check cases like x^y==z */
2392 if (TREE_CODE_CLASS (code1) == tcc_comparison
2393 || TREE_CODE_CLASS (code2) == tcc_comparison)
2394 warning (0, "suggest parentheses around comparison in operand of ^");
2397 if (code == BIT_AND_EXPR)
2399 if (code1 == PLUS_EXPR || code1 == MINUS_EXPR
2400 || code2 == PLUS_EXPR || code2 == MINUS_EXPR)
2401 warning (0, "suggest parentheses around + or - in operand of &");
2402 /* Check cases like x&y==z */
2403 if (TREE_CODE_CLASS (code1) == tcc_comparison
2404 || TREE_CODE_CLASS (code2) == tcc_comparison)
2405 warning (0, "suggest parentheses around comparison in operand of &");
2407 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
2408 if (TREE_CODE_CLASS (code) == tcc_comparison
2409 && (TREE_CODE_CLASS (code1) == tcc_comparison
2410 || TREE_CODE_CLASS (code2) == tcc_comparison))
2411 warning (0, "comparisons like X<=Y<=Z do not have their mathematical meaning");
2415 unsigned_conversion_warning (result.value, arg1.value);
2416 unsigned_conversion_warning (result.value, arg2.value);
2417 overflow_warning (result.value);
2422 /* Return a tree for the difference of pointers OP0 and OP1.
2423 The resulting tree has type int. */
2426 pointer_diff (tree op0, tree op1)
2428 tree restype = ptrdiff_type_node;
2430 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2431 tree con0, con1, lit0, lit1;
2432 tree orig_op1 = op1;
2434 if (pedantic || warn_pointer_arith)
2436 if (TREE_CODE (target_type) == VOID_TYPE)
2437 pedwarn ("pointer of type %<void *%> used in subtraction");
2438 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2439 pedwarn ("pointer to a function used in subtraction");
2442 /* If the conversion to ptrdiff_type does anything like widening or
2443 converting a partial to an integral mode, we get a convert_expression
2444 that is in the way to do any simplifications.
2445 (fold-const.c doesn't know that the extra bits won't be needed.
2446 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2447 different mode in place.)
2448 So first try to find a common term here 'by hand'; we want to cover
2449 at least the cases that occur in legal static initializers. */
2450 con0 = TREE_CODE (op0) == NOP_EXPR ? TREE_OPERAND (op0, 0) : op0;
2451 con1 = TREE_CODE (op1) == NOP_EXPR ? TREE_OPERAND (op1, 0) : op1;
2453 if (TREE_CODE (con0) == PLUS_EXPR)
2455 lit0 = TREE_OPERAND (con0, 1);
2456 con0 = TREE_OPERAND (con0, 0);
2459 lit0 = integer_zero_node;
2461 if (TREE_CODE (con1) == PLUS_EXPR)
2463 lit1 = TREE_OPERAND (con1, 1);
2464 con1 = TREE_OPERAND (con1, 0);
2467 lit1 = integer_zero_node;
2469 if (operand_equal_p (con0, con1, 0))
2476 /* First do the subtraction as integers;
2477 then drop through to build the divide operator.
2478 Do not do default conversions on the minus operator
2479 in case restype is a short type. */
2481 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2482 convert (restype, op1), 0);
2483 /* This generates an error if op1 is pointer to incomplete type. */
2484 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2485 error ("arithmetic on pointer to an incomplete type");
2487 /* This generates an error if op0 is pointer to incomplete type. */
2488 op1 = c_size_in_bytes (target_type);
2490 /* Divide by the size, in easiest possible way. */
2491 return fold (build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)));
2494 /* Construct and perhaps optimize a tree representation
2495 for a unary operation. CODE, a tree_code, specifies the operation
2496 and XARG is the operand.
2497 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2498 the default promotions (such as from short to int).
2499 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2500 allows non-lvalues; this is only used to handle conversion of non-lvalue
2501 arrays to pointers in C99. */
2504 build_unary_op (enum tree_code code, tree xarg, int flag)
2506 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2509 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2511 int noconvert = flag;
2513 if (typecode == ERROR_MARK)
2514 return error_mark_node;
2515 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2516 typecode = INTEGER_TYPE;
2521 /* This is used for unary plus, because a CONVERT_EXPR
2522 is enough to prevent anybody from looking inside for
2523 associativity, but won't generate any code. */
2524 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2525 || typecode == COMPLEX_TYPE
2526 || typecode == VECTOR_TYPE))
2528 error ("wrong type argument to unary plus");
2529 return error_mark_node;
2531 else if (!noconvert)
2532 arg = default_conversion (arg);
2533 arg = non_lvalue (arg);
2537 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2538 || typecode == COMPLEX_TYPE
2539 || typecode == VECTOR_TYPE))
2541 error ("wrong type argument to unary minus");
2542 return error_mark_node;
2544 else if (!noconvert)
2545 arg = default_conversion (arg);
2549 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2552 arg = default_conversion (arg);
2554 else if (typecode == COMPLEX_TYPE)
2558 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2560 arg = default_conversion (arg);
2564 error ("wrong type argument to bit-complement");
2565 return error_mark_node;
2570 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2572 error ("wrong type argument to abs");
2573 return error_mark_node;
2575 else if (!noconvert)
2576 arg = default_conversion (arg);
2580 /* Conjugating a real value is a no-op, but allow it anyway. */
2581 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2582 || typecode == COMPLEX_TYPE))
2584 error ("wrong type argument to conjugation");
2585 return error_mark_node;
2587 else if (!noconvert)
2588 arg = default_conversion (arg);
2591 case TRUTH_NOT_EXPR:
2592 /* ??? Why do most validation here but that for non-lvalue arrays
2593 in c_objc_common_truthvalue_conversion? */
2594 if (typecode != INTEGER_TYPE
2595 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2596 && typecode != COMPLEX_TYPE
2597 /* These will convert to a pointer. */
2598 && typecode != ARRAY_TYPE && typecode != FUNCTION_TYPE)
2600 error ("wrong type argument to unary exclamation mark");
2601 return error_mark_node;
2603 arg = c_objc_common_truthvalue_conversion (arg);
2604 return invert_truthvalue (arg);
2610 if (TREE_CODE (arg) == COMPLEX_CST)
2611 return TREE_REALPART (arg);
2612 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2613 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2618 if (TREE_CODE (arg) == COMPLEX_CST)
2619 return TREE_IMAGPART (arg);
2620 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2621 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
2623 return convert (TREE_TYPE (arg), integer_zero_node);
2625 case PREINCREMENT_EXPR:
2626 case POSTINCREMENT_EXPR:
2627 case PREDECREMENT_EXPR:
2628 case POSTDECREMENT_EXPR:
2630 /* Increment or decrement the real part of the value,
2631 and don't change the imaginary part. */
2632 if (typecode == COMPLEX_TYPE)
2637 pedwarn ("ISO C does not support %<++%> and %<--%>"
2638 " on complex types");
2640 arg = stabilize_reference (arg);
2641 real = build_unary_op (REALPART_EXPR, arg, 1);
2642 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2643 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2644 build_unary_op (code, real, 1), imag);
2647 /* Report invalid types. */
2649 if (typecode != POINTER_TYPE
2650 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2652 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2653 error ("wrong type argument to increment");
2655 error ("wrong type argument to decrement");
2657 return error_mark_node;
2662 tree result_type = TREE_TYPE (arg);
2664 arg = get_unwidened (arg, 0);
2665 argtype = TREE_TYPE (arg);
2667 /* Compute the increment. */
2669 if (typecode == POINTER_TYPE)
2671 /* If pointer target is an undefined struct,
2672 we just cannot know how to do the arithmetic. */
2673 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2675 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2676 error ("increment of pointer to unknown structure");
2678 error ("decrement of pointer to unknown structure");
2680 else if ((pedantic || warn_pointer_arith)
2681 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2682 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2684 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2685 pedwarn ("wrong type argument to increment");
2687 pedwarn ("wrong type argument to decrement");
2690 inc = c_size_in_bytes (TREE_TYPE (result_type));
2693 inc = integer_one_node;
2695 inc = convert (argtype, inc);
2697 /* Complain about anything else that is not a true lvalue. */
2698 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2699 || code == POSTINCREMENT_EXPR)
2702 return error_mark_node;
2704 /* Report a read-only lvalue. */
2705 if (TREE_READONLY (arg))
2706 readonly_error (arg,
2707 ((code == PREINCREMENT_EXPR
2708 || code == POSTINCREMENT_EXPR)
2709 ? lv_increment : lv_decrement));
2711 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2712 val = boolean_increment (code, arg);
2714 val = build2 (code, TREE_TYPE (arg), arg, inc);
2715 TREE_SIDE_EFFECTS (val) = 1;
2716 val = convert (result_type, val);
2717 if (TREE_CODE (val) != code)
2718 TREE_NO_WARNING (val) = 1;
2723 /* Note that this operation never does default_conversion. */
2725 /* Let &* cancel out to simplify resulting code. */
2726 if (TREE_CODE (arg) == INDIRECT_REF)
2728 /* Don't let this be an lvalue. */
2729 if (lvalue_p (TREE_OPERAND (arg, 0)))
2730 return non_lvalue (TREE_OPERAND (arg, 0));
2731 return TREE_OPERAND (arg, 0);
2734 /* For &x[y], return x+y */
2735 if (TREE_CODE (arg) == ARRAY_REF)
2737 if (!c_mark_addressable (TREE_OPERAND (arg, 0)))
2738 return error_mark_node;
2739 return build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
2740 TREE_OPERAND (arg, 1), 1);
2743 /* Anything not already handled and not a true memory reference
2744 or a non-lvalue array is an error. */
2745 else if (typecode != FUNCTION_TYPE && !flag
2746 && !lvalue_or_else (arg, lv_addressof))
2747 return error_mark_node;
2749 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2750 argtype = TREE_TYPE (arg);
2752 /* If the lvalue is const or volatile, merge that into the type
2753 to which the address will point. Note that you can't get a
2754 restricted pointer by taking the address of something, so we
2755 only have to deal with `const' and `volatile' here. */
2756 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
2757 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
2758 argtype = c_build_type_variant (argtype,
2759 TREE_READONLY (arg),
2760 TREE_THIS_VOLATILE (arg));
2762 if (!c_mark_addressable (arg))
2763 return error_mark_node;
2765 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
2766 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
2768 argtype = build_pointer_type (argtype);
2770 /* ??? Cope with user tricks that amount to offsetof. Delete this
2771 when we have proper support for integer constant expressions. */
2772 val = get_base_address (arg);
2773 if (val && TREE_CODE (val) == INDIRECT_REF
2774 && integer_zerop (TREE_OPERAND (val, 0)))
2775 return fold_convert (argtype, fold_offsetof (arg));
2777 val = build1 (ADDR_EXPR, argtype, arg);
2779 if (TREE_CODE (arg) == COMPOUND_LITERAL_EXPR)
2780 TREE_INVARIANT (val) = TREE_CONSTANT (val) = 1;
2789 argtype = TREE_TYPE (arg);
2790 val = build1 (code, argtype, arg);
2791 return require_constant_value ? fold_initializer (val) : fold (val);
2794 /* Return nonzero if REF is an lvalue valid for this language.
2795 Lvalues can be assigned, unless their type has TYPE_READONLY.
2796 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
2801 enum tree_code code = TREE_CODE (ref);
2808 return lvalue_p (TREE_OPERAND (ref, 0));
2810 case COMPOUND_LITERAL_EXPR:
2820 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
2821 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
2824 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
2831 /* Give an error for storing in something that is 'const'. */
2834 readonly_error (tree arg, enum lvalue_use use)
2836 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement);
2837 /* Using this macro rather than (for example) arrays of messages
2838 ensures that all the format strings are checked at compile
2840 #define READONLY_MSG(A, I, D) (use == lv_assign \
2842 : (use == lv_increment ? (I) : (D)))
2843 if (TREE_CODE (arg) == COMPONENT_REF)
2845 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
2846 readonly_error (TREE_OPERAND (arg, 0), use);
2848 error (READONLY_MSG (G_("assignment of read-only member %qD"),
2849 G_("increment of read-only member %qD"),
2850 G_("decrement of read-only member %qD")),
2851 TREE_OPERAND (arg, 1));
2853 else if (TREE_CODE (arg) == VAR_DECL)
2854 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
2855 G_("increment of read-only variable %qD"),
2856 G_("decrement of read-only variable %qD")),
2859 error (READONLY_MSG (G_("assignment of read-only location"),
2860 G_("increment of read-only location"),
2861 G_("decrement of read-only location")));
2865 /* Return nonzero if REF is an lvalue valid for this language;
2866 otherwise, print an error message and return zero. USE says
2867 how the lvalue is being used and so selects the error message. */
2870 lvalue_or_else (tree ref, enum lvalue_use use)
2872 int win = lvalue_p (ref);
2880 /* Mark EXP saying that we need to be able to take the
2881 address of it; it should not be allocated in a register.
2882 Returns true if successful. */
2885 c_mark_addressable (tree exp)
2890 switch (TREE_CODE (x))
2893 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
2896 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
2900 /* ... fall through ... */
2906 x = TREE_OPERAND (x, 0);
2909 case COMPOUND_LITERAL_EXPR:
2911 TREE_ADDRESSABLE (x) = 1;
2918 if (C_DECL_REGISTER (x)
2919 && DECL_NONLOCAL (x))
2921 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2924 ("global register variable %qD used in nested function", x);
2927 pedwarn ("register variable %qD used in nested function", x);
2929 else if (C_DECL_REGISTER (x))
2931 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
2932 error ("address of global register variable %qD requested", x);
2934 error ("address of register variable %qD requested", x);
2940 TREE_ADDRESSABLE (x) = 1;
2947 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
2950 build_conditional_expr (tree ifexp, tree op1, tree op2)
2954 enum tree_code code1;
2955 enum tree_code code2;
2956 tree result_type = NULL;
2957 tree orig_op1 = op1, orig_op2 = op2;
2959 /* Promote both alternatives. */
2961 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
2962 op1 = default_conversion (op1);
2963 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
2964 op2 = default_conversion (op2);
2966 if (TREE_CODE (ifexp) == ERROR_MARK
2967 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
2968 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
2969 return error_mark_node;
2971 type1 = TREE_TYPE (op1);
2972 code1 = TREE_CODE (type1);
2973 type2 = TREE_TYPE (op2);
2974 code2 = TREE_CODE (type2);
2976 /* C90 does not permit non-lvalue arrays in conditional expressions.
2977 In C99 they will be pointers by now. */
2978 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
2980 error ("non-lvalue array in conditional expression");
2981 return error_mark_node;
2984 /* Quickly detect the usual case where op1 and op2 have the same type
2986 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
2989 result_type = type1;
2991 result_type = TYPE_MAIN_VARIANT (type1);
2993 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
2994 || code1 == COMPLEX_TYPE)
2995 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
2996 || code2 == COMPLEX_TYPE))
2998 result_type = c_common_type (type1, type2);
3000 /* If -Wsign-compare, warn here if type1 and type2 have
3001 different signedness. We'll promote the signed to unsigned
3002 and later code won't know it used to be different.
3003 Do this check on the original types, so that explicit casts
3004 will be considered, but default promotions won't. */
3005 if (warn_sign_compare && !skip_evaluation)
3007 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3008 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3010 if (unsigned_op1 ^ unsigned_op2)
3012 /* Do not warn if the result type is signed, since the
3013 signed type will only be chosen if it can represent
3014 all the values of the unsigned type. */
3015 if (!TYPE_UNSIGNED (result_type))
3017 /* Do not warn if the signed quantity is an unsuffixed
3018 integer literal (or some static constant expression
3019 involving such literals) and it is non-negative. */
3020 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3021 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3024 warning (0, "signed and unsigned type in conditional expression");
3028 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3030 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3031 pedwarn ("ISO C forbids conditional expr with only one void side");
3032 result_type = void_type_node;
3034 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3036 if (comp_target_types (type1, type2))
3037 result_type = common_pointer_type (type1, type2);
3038 else if (integer_zerop (op1) && TREE_TYPE (type1) == void_type_node
3039 && TREE_CODE (orig_op1) != NOP_EXPR)
3040 result_type = qualify_type (type2, type1);
3041 else if (integer_zerop (op2) && TREE_TYPE (type2) == void_type_node
3042 && TREE_CODE (orig_op2) != NOP_EXPR)
3043 result_type = qualify_type (type1, type2);
3044 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3046 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3047 pedwarn ("ISO C forbids conditional expr between "
3048 "%<void *%> and function pointer");
3049 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3050 TREE_TYPE (type2)));
3052 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3054 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3055 pedwarn ("ISO C forbids conditional expr between "
3056 "%<void *%> and function pointer");
3057 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3058 TREE_TYPE (type1)));
3062 pedwarn ("pointer type mismatch in conditional expression");
3063 result_type = build_pointer_type (void_type_node);
3066 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3068 if (!integer_zerop (op2))
3069 pedwarn ("pointer/integer type mismatch in conditional expression");
3072 op2 = null_pointer_node;
3074 result_type = type1;
3076 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3078 if (!integer_zerop (op1))
3079 pedwarn ("pointer/integer type mismatch in conditional expression");
3082 op1 = null_pointer_node;
3084 result_type = type2;
3089 if (flag_cond_mismatch)
3090 result_type = void_type_node;
3093 error ("type mismatch in conditional expression");
3094 return error_mark_node;
3098 /* Merge const and volatile flags of the incoming types. */
3100 = build_type_variant (result_type,
3101 TREE_READONLY (op1) || TREE_READONLY (op2),
3102 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3104 if (result_type != TREE_TYPE (op1))
3105 op1 = convert_and_check (result_type, op1);
3106 if (result_type != TREE_TYPE (op2))
3107 op2 = convert_and_check (result_type, op2);
3109 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3112 /* Return a compound expression that performs two expressions and
3113 returns the value of the second of them. */
3116 build_compound_expr (tree expr1, tree expr2)
3118 /* Convert arrays and functions to pointers. */
3119 expr2 = default_function_array_conversion (expr2);
3121 if (!TREE_SIDE_EFFECTS (expr1))
3123 /* The left-hand operand of a comma expression is like an expression
3124 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3125 any side-effects, unless it was explicitly cast to (void). */
3126 if (warn_unused_value)
3128 if (VOID_TYPE_P (TREE_TYPE (expr1))
3129 && TREE_CODE (expr1) == CONVERT_EXPR)
3131 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3132 && TREE_CODE (expr1) == COMPOUND_EXPR
3133 && TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR)
3134 ; /* (void) a, (void) b, c */
3136 warning (0, "left-hand operand of comma expression has no effect");
3140 /* With -Wunused, we should also warn if the left-hand operand does have
3141 side-effects, but computes a value which is not used. For example, in
3142 `foo() + bar(), baz()' the result of the `+' operator is not used,
3143 so we should issue a warning. */
3144 else if (warn_unused_value)
3145 warn_if_unused_value (expr1, input_location);
3147 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3150 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3153 build_c_cast (tree type, tree expr)
3157 if (type == error_mark_node || expr == error_mark_node)
3158 return error_mark_node;
3160 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3161 only in <protocol> qualifications. But when constructing cast expressions,
3162 the protocols do matter and must be kept around. */
3163 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3164 return build1 (NOP_EXPR, type, expr);
3166 type = TYPE_MAIN_VARIANT (type);
3168 if (TREE_CODE (type) == ARRAY_TYPE)
3170 error ("cast specifies array type");
3171 return error_mark_node;
3174 if (TREE_CODE (type) == FUNCTION_TYPE)
3176 error ("cast specifies function type");
3177 return error_mark_node;
3180 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3184 if (TREE_CODE (type) == RECORD_TYPE
3185 || TREE_CODE (type) == UNION_TYPE)
3186 pedwarn ("ISO C forbids casting nonscalar to the same type");
3189 else if (TREE_CODE (type) == UNION_TYPE)
3192 value = default_function_array_conversion (value);
3194 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3195 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3196 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3204 pedwarn ("ISO C forbids casts to union type");
3205 t = digest_init (type,
3206 build_constructor (type,
3207 build_tree_list (field, value)),
3209 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3210 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3213 error ("cast to union type from type not present in union");
3214 return error_mark_node;
3220 /* If casting to void, avoid the error that would come
3221 from default_conversion in the case of a non-lvalue array. */
3222 if (type == void_type_node)
3223 return build1 (CONVERT_EXPR, type, value);
3225 /* Convert functions and arrays to pointers,
3226 but don't convert any other types. */
3227 value = default_function_array_conversion (value);
3228 otype = TREE_TYPE (value);
3230 /* Optionally warn about potentially worrisome casts. */
3233 && TREE_CODE (type) == POINTER_TYPE
3234 && TREE_CODE (otype) == POINTER_TYPE)
3236 tree in_type = type;
3237 tree in_otype = otype;
3241 /* Check that the qualifiers on IN_TYPE are a superset of
3242 the qualifiers of IN_OTYPE. The outermost level of
3243 POINTER_TYPE nodes is uninteresting and we stop as soon
3244 as we hit a non-POINTER_TYPE node on either type. */
3247 in_otype = TREE_TYPE (in_otype);
3248 in_type = TREE_TYPE (in_type);
3250 /* GNU C allows cv-qualified function types. 'const'
3251 means the function is very pure, 'volatile' means it
3252 can't return. We need to warn when such qualifiers
3253 are added, not when they're taken away. */
3254 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3255 && TREE_CODE (in_type) == FUNCTION_TYPE)
3256 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3258 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3260 while (TREE_CODE (in_type) == POINTER_TYPE
3261 && TREE_CODE (in_otype) == POINTER_TYPE);
3264 warning (0, "cast adds new qualifiers to function type");
3267 /* There are qualifiers present in IN_OTYPE that are not
3268 present in IN_TYPE. */
3269 warning (0, "cast discards qualifiers from pointer target type");
3272 /* Warn about possible alignment problems. */
3273 if (STRICT_ALIGNMENT && warn_cast_align
3274 && TREE_CODE (type) == POINTER_TYPE
3275 && TREE_CODE (otype) == POINTER_TYPE
3276 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3277 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3278 /* Don't warn about opaque types, where the actual alignment
3279 restriction is unknown. */
3280 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3281 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3282 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3283 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3284 warning (0, "cast increases required alignment of target type");
3286 if (warn_pointer_to_int_cast
3287 && TREE_CODE (type) == INTEGER_TYPE
3288 && TREE_CODE (otype) == POINTER_TYPE
3289 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3290 && !TREE_CONSTANT (value))
3291 warning (0, "cast from pointer to integer of different size");
3293 if (warn_bad_function_cast
3294 && TREE_CODE (value) == CALL_EXPR
3295 && TREE_CODE (type) != TREE_CODE (otype))
3296 warning (0, "cast from function call of type %qT to non-matching "
3297 "type %qT", otype, type);
3299 if (warn_int_to_pointer_cast
3300 && TREE_CODE (type) == POINTER_TYPE
3301 && TREE_CODE (otype) == INTEGER_TYPE
3302 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3303 /* Don't warn about converting any constant. */
3304 && !TREE_CONSTANT (value))
3305 warning (0, "cast to pointer from integer of different size");
3307 if (flag_strict_aliasing && warn_strict_aliasing
3308 && TREE_CODE (type) == POINTER_TYPE
3309 && TREE_CODE (otype) == POINTER_TYPE
3310 && TREE_CODE (expr) == ADDR_EXPR
3311 && (DECL_P (TREE_OPERAND (expr, 0))
3312 || TREE_CODE (TREE_OPERAND (expr, 0)) == COMPONENT_REF)
3313 && !VOID_TYPE_P (TREE_TYPE (type)))
3315 /* Casting the address of an object to non void pointer. Warn
3316 if the cast breaks type based aliasing. */
3317 if (!COMPLETE_TYPE_P (TREE_TYPE (type)))
3318 warning (0, "type-punning to incomplete type might break strict-aliasing rules");
3321 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
3322 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
3324 if (!alias_sets_conflict_p (set1, set2))
3325 warning (0, "dereferencing type-punned pointer will break strict-aliasing rules");
3326 else if (warn_strict_aliasing > 1
3327 && !alias_sets_might_conflict_p (set1, set2))
3328 warning (0, "dereferencing type-punned pointer might break strict-aliasing rules");
3332 /* If pedantic, warn for conversions between function and object
3333 pointer types, except for converting a null pointer constant
3334 to function pointer type. */
3336 && TREE_CODE (type) == POINTER_TYPE
3337 && TREE_CODE (otype) == POINTER_TYPE
3338 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3339 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3340 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3343 && TREE_CODE (type) == POINTER_TYPE
3344 && TREE_CODE (otype) == POINTER_TYPE
3345 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3346 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3347 && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node
3348 && TREE_CODE (expr) != NOP_EXPR))
3349 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3352 value = convert (type, value);
3354 /* Ignore any integer overflow caused by the cast. */
3355 if (TREE_CODE (value) == INTEGER_CST)
3357 if (EXPR_P (ovalue))
3358 /* If OVALUE had overflow set, then so will VALUE, so it
3359 is safe to overwrite. */
3360 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3362 TREE_OVERFLOW (value) = 0;
3364 if (CONSTANT_CLASS_P (ovalue))
3365 /* Similarly, constant_overflow cannot have become
3367 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3371 /* Don't let a cast be an lvalue. */
3373 value = non_lvalue (value);
3378 /* Interpret a cast of expression EXPR to type TYPE. */
3380 c_cast_expr (struct c_type_name *type_name, tree expr)
3383 int saved_wsp = warn_strict_prototypes;
3385 /* This avoids warnings about unprototyped casts on
3386 integers. E.g. "#define SIG_DFL (void(*)())0". */
3387 if (TREE_CODE (expr) == INTEGER_CST)
3388 warn_strict_prototypes = 0;
3389 type = groktypename (type_name);
3390 warn_strict_prototypes = saved_wsp;
3392 return build_c_cast (type, expr);
3396 /* Build an assignment expression of lvalue LHS from value RHS.
3397 MODIFYCODE is the code for a binary operator that we use
3398 to combine the old value of LHS with RHS to get the new value.
3399 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3402 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3406 tree lhstype = TREE_TYPE (lhs);
3407 tree olhstype = lhstype;
3409 /* Types that aren't fully specified cannot be used in assignments. */
3410 lhs = require_complete_type (lhs);
3412 /* Avoid duplicate error messages from operands that had errors. */
3413 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3414 return error_mark_node;
3416 STRIP_TYPE_NOPS (rhs);
3420 /* If a binary op has been requested, combine the old LHS value with the RHS
3421 producing the value we should actually store into the LHS. */
3423 if (modifycode != NOP_EXPR)
3425 lhs = stabilize_reference (lhs);
3426 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3429 if (!lvalue_or_else (lhs, lv_assign))
3430 return error_mark_node;
3432 /* Give an error for storing in something that is 'const'. */
3434 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3435 || ((TREE_CODE (lhstype) == RECORD_TYPE
3436 || TREE_CODE (lhstype) == UNION_TYPE)
3437 && C_TYPE_FIELDS_READONLY (lhstype)))
3438 readonly_error (lhs, lv_assign);
3440 /* If storing into a structure or union member,
3441 it has probably been given type `int'.
3442 Compute the type that would go with
3443 the actual amount of storage the member occupies. */
3445 if (TREE_CODE (lhs) == COMPONENT_REF
3446 && (TREE_CODE (lhstype) == INTEGER_TYPE
3447 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3448 || TREE_CODE (lhstype) == REAL_TYPE
3449 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3450 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3452 /* If storing in a field that is in actuality a short or narrower than one,
3453 we must store in the field in its actual type. */
3455 if (lhstype != TREE_TYPE (lhs))
3457 lhs = copy_node (lhs);
3458 TREE_TYPE (lhs) = lhstype;
3461 /* Convert new value to destination type. */
3463 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3464 NULL_TREE, NULL_TREE, 0);
3465 if (TREE_CODE (newrhs) == ERROR_MARK)
3466 return error_mark_node;
3468 /* Emit ObjC write barrier, if necessary. */
3469 if (c_dialect_objc () && flag_objc_gc)
3471 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3476 /* Scan operands. */
3478 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3479 TREE_SIDE_EFFECTS (result) = 1;
3481 /* If we got the LHS in a different type for storing in,
3482 convert the result back to the nominal type of LHS
3483 so that the value we return always has the same type
3484 as the LHS argument. */
3486 if (olhstype == TREE_TYPE (result))
3488 return convert_for_assignment (olhstype, result, ic_assign,
3489 NULL_TREE, NULL_TREE, 0);
3492 /* Convert value RHS to type TYPE as preparation for an assignment
3493 to an lvalue of type TYPE.
3494 The real work of conversion is done by `convert'.
3495 The purpose of this function is to generate error messages
3496 for assignments that are not allowed in C.
3497 ERRTYPE says whether it is argument passing, assignment,
3498 initialization or return.
3500 FUNCTION is a tree for the function being called.
3501 PARMNUM is the number of the argument, for printing in error messages. */
3504 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3505 tree fundecl, tree function, int parmnum)
3507 enum tree_code codel = TREE_CODE (type);
3509 enum tree_code coder;
3510 tree rname = NULL_TREE;
3511 bool objc_ok = false;
3513 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3516 /* Change pointer to function to the function itself for
3518 if (TREE_CODE (function) == ADDR_EXPR
3519 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3520 function = TREE_OPERAND (function, 0);
3522 /* Handle an ObjC selector specially for diagnostics. */
3523 selector = objc_message_selector ();
3525 if (selector && parmnum > 2)
3532 /* This macro is used to emit diagnostics to ensure that all format
3533 strings are complete sentences, visible to gettext and checked at
3535 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3540 pedwarn (AR, parmnum, rname); \
3542 case ic_argpass_nonproto: \
3543 warning (0, AR, parmnum, rname); \
3555 gcc_unreachable (); \
3559 STRIP_TYPE_NOPS (rhs);
3561 if (TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
3562 || TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE)
3563 rhs = default_conversion (rhs);
3564 else if (optimize && TREE_CODE (rhs) == VAR_DECL)
3565 rhs = decl_constant_value_for_broken_optimization (rhs);
3567 rhstype = TREE_TYPE (rhs);
3568 coder = TREE_CODE (rhstype);
3570 if (coder == ERROR_MARK)
3571 return error_mark_node;
3573 if (c_dialect_objc ())
3596 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3599 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3601 overflow_warning (rhs);
3605 if (coder == VOID_TYPE)
3607 /* Except for passing an argument to an unprototyped function,
3608 this is a constraint violation. When passing an argument to
3609 an unprototyped function, it is compile-time undefined;
3610 making it a constraint in that case was rejected in
3612 error ("void value not ignored as it ought to be");
3613 return error_mark_node;
3615 /* A type converts to a reference to it.
3616 This code doesn't fully support references, it's just for the
3617 special case of va_start and va_copy. */
3618 if (codel == REFERENCE_TYPE
3619 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3621 if (!lvalue_p (rhs))
3623 error ("cannot pass rvalue to reference parameter");
3624 return error_mark_node;
3626 if (!c_mark_addressable (rhs))
3627 return error_mark_node;
3628 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3630 /* We already know that these two types are compatible, but they
3631 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3632 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3633 likely to be va_list, a typedef to __builtin_va_list, which
3634 is different enough that it will cause problems later. */
3635 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3636 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3638 rhs = build1 (NOP_EXPR, type, rhs);
3641 /* Some types can interconvert without explicit casts. */
3642 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3643 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3644 return convert (type, rhs);
3645 /* Arithmetic types all interconvert, and enum is treated like int. */
3646 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3647 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3648 || codel == BOOLEAN_TYPE)
3649 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3650 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3651 || coder == BOOLEAN_TYPE))
3652 return convert_and_check (type, rhs);
3654 /* Conversion to a transparent union from its member types.
3655 This applies only to function arguments. */
3656 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3657 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3660 tree marginal_memb_type = 0;
3662 for (memb_types = TYPE_FIELDS (type); memb_types;
3663 memb_types = TREE_CHAIN (memb_types))
3665 tree memb_type = TREE_TYPE (memb_types);
3667 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3668 TYPE_MAIN_VARIANT (rhstype)))
3671 if (TREE_CODE (memb_type) != POINTER_TYPE)
3674 if (coder == POINTER_TYPE)
3676 tree ttl = TREE_TYPE (memb_type);
3677 tree ttr = TREE_TYPE (rhstype);
3679 /* Any non-function converts to a [const][volatile] void *
3680 and vice versa; otherwise, targets must be the same.
3681 Meanwhile, the lhs target must have all the qualifiers of
3683 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3684 || comp_target_types (memb_type, rhstype))
3686 /* If this type won't generate any warnings, use it. */
3687 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3688 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3689 && TREE_CODE (ttl) == FUNCTION_TYPE)
3690 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3691 == TYPE_QUALS (ttr))
3692 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3693 == TYPE_QUALS (ttl))))
3696 /* Keep looking for a better type, but remember this one. */
3697 if (!marginal_memb_type)
3698 marginal_memb_type = memb_type;
3702 /* Can convert integer zero to any pointer type. */
3703 if (integer_zerop (rhs)
3704 || (TREE_CODE (rhs) == NOP_EXPR
3705 && integer_zerop (TREE_OPERAND (rhs, 0))))
3707 rhs = null_pointer_node;
3712 if (memb_types || marginal_memb_type)
3716 /* We have only a marginally acceptable member type;
3717 it needs a warning. */
3718 tree ttl = TREE_TYPE (marginal_memb_type);
3719 tree ttr = TREE_TYPE (rhstype);
3721 /* Const and volatile mean something different for function
3722 types, so the usual warnings are not appropriate. */
3723 if (TREE_CODE (ttr) == FUNCTION_TYPE
3724 && TREE_CODE (ttl) == FUNCTION_TYPE)
3726 /* Because const and volatile on functions are
3727 restrictions that say the function will not do
3728 certain things, it is okay to use a const or volatile
3729 function where an ordinary one is wanted, but not
3731 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3732 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3733 "makes qualified function "
3734 "pointer from unqualified"),
3735 G_("assignment makes qualified "
3736 "function pointer from "
3738 G_("initialization makes qualified "
3739 "function pointer from "
3741 G_("return makes qualified function "
3742 "pointer from unqualified"));
3744 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3745 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3746 "qualifiers from pointer target type"),
3747 G_("assignment discards qualifiers "
3748 "from pointer target type"),
3749 G_("initialization discards qualifiers "
3750 "from pointer target type"),
3751 G_("return discards qualifiers from "
3752 "pointer target type"));
3755 if (pedantic && !DECL_IN_SYSTEM_HEADER (fundecl))
3756 pedwarn ("ISO C prohibits argument conversion to union type");
3758 return build1 (NOP_EXPR, type, rhs);
3762 /* Conversions among pointers */
3763 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3764 && (coder == codel))
3766 tree ttl = TREE_TYPE (type);
3767 tree ttr = TREE_TYPE (rhstype);
3770 bool is_opaque_pointer;
3771 int target_cmp = 0; /* Cache comp_target_types () result. */
3773 if (TREE_CODE (mvl) != ARRAY_TYPE)
3774 mvl = TYPE_MAIN_VARIANT (mvl);
3775 if (TREE_CODE (mvr) != ARRAY_TYPE)
3776 mvr = TYPE_MAIN_VARIANT (mvr);
3777 /* Opaque pointers are treated like void pointers. */
3778 is_opaque_pointer = (targetm.vector_opaque_p (type)
3779 || targetm.vector_opaque_p (rhstype))
3780 && TREE_CODE (ttl) == VECTOR_TYPE
3781 && TREE_CODE (ttr) == VECTOR_TYPE;
3783 /* Any non-function converts to a [const][volatile] void *
3784 and vice versa; otherwise, targets must be the same.
3785 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
3786 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3787 || (target_cmp = comp_target_types (type, rhstype))
3788 || is_opaque_pointer
3789 || (c_common_unsigned_type (mvl)
3790 == c_common_unsigned_type (mvr)))
3793 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
3796 /* Check TREE_CODE to catch cases like (void *) (char *) 0
3797 which are not ANSI null ptr constants. */
3798 && (!integer_zerop (rhs) || TREE_CODE (rhs) == NOP_EXPR)
3799 && TREE_CODE (ttl) == FUNCTION_TYPE)))
3800 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
3801 "%qE between function pointer "
3803 G_("ISO C forbids assignment between "
3804 "function pointer and %<void *%>"),
3805 G_("ISO C forbids initialization between "
3806 "function pointer and %<void *%>"),
3807 G_("ISO C forbids return between function "
3808 "pointer and %<void *%>"));
3809 /* Const and volatile mean something different for function types,
3810 so the usual warnings are not appropriate. */
3811 else if (TREE_CODE (ttr) != FUNCTION_TYPE
3812 && TREE_CODE (ttl) != FUNCTION_TYPE)
3814 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3816 /* Types differing only by the presence of the 'volatile'
3817 qualifier are acceptable if the 'volatile' has been added
3818 in by the Objective-C EH machinery. */
3819 if (!objc_type_quals_match (ttl, ttr))
3820 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3821 "qualifiers from pointer target type"),
3822 G_("assignment discards qualifiers "
3823 "from pointer target type"),
3824 G_("initialization discards qualifiers "
3825 "from pointer target type"),
3826 G_("return discards qualifiers from "
3827 "pointer target type"));
3829 /* If this is not a case of ignoring a mismatch in signedness,
3831 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3834 /* If there is a mismatch, do warn. */
3835 else if (warn_pointer_sign)
3836 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
3837 "%d of %qE differ in signedness"),
3838 G_("pointer targets in assignment "
3839 "differ in signedness"),
3840 G_("pointer targets in initialization "
3841 "differ in signedness"),
3842 G_("pointer targets in return differ "
3845 else if (TREE_CODE (ttl) == FUNCTION_TYPE
3846 && TREE_CODE (ttr) == FUNCTION_TYPE)
3848 /* Because const and volatile on functions are restrictions
3849 that say the function will not do certain things,
3850 it is okay to use a const or volatile function
3851 where an ordinary one is wanted, but not vice-versa. */
3852 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3853 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3854 "qualified function pointer "
3855 "from unqualified"),
3856 G_("assignment makes qualified function "
3857 "pointer from unqualified"),
3858 G_("initialization makes qualified "
3859 "function pointer from unqualified"),
3860 G_("return makes qualified function "
3861 "pointer from unqualified"));
3865 /* Avoid warning about the volatile ObjC EH puts on decls. */
3867 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
3868 "incompatible pointer type"),
3869 G_("assignment from incompatible pointer type"),
3870 G_("initialization from incompatible "
3872 G_("return from incompatible pointer type"));
3874 return convert (type, rhs);
3876 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
3878 /* ??? This should not be an error when inlining calls to
3879 unprototyped functions. */
3880 error ("invalid use of non-lvalue array");
3881 return error_mark_node;
3883 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
3885 /* An explicit constant 0 can convert to a pointer,
3886 or one that results from arithmetic, even including
3887 a cast to integer type. */
3888 if (!(TREE_CODE (rhs) == INTEGER_CST && integer_zerop (rhs))
3890 !(TREE_CODE (rhs) == NOP_EXPR
3891 && TREE_CODE (TREE_TYPE (rhs)) == INTEGER_TYPE
3892 && TREE_CODE (TREE_OPERAND (rhs, 0)) == INTEGER_CST
3893 && integer_zerop (TREE_OPERAND (rhs, 0))))
3894 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
3895 "pointer from integer without a cast"),
3896 G_("assignment makes pointer from integer "
3898 G_("initialization makes pointer from "
3899 "integer without a cast"),
3900 G_("return makes pointer from integer "
3903 return convert (type, rhs);
3905 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
3907 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
3908 "from pointer without a cast"),
3909 G_("assignment makes integer from pointer "
3911 G_("initialization makes integer from pointer "
3913 G_("return makes integer from pointer "
3915 return convert (type, rhs);
3917 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
3918 return convert (type, rhs);
3923 case ic_argpass_nonproto:
3924 /* ??? This should not be an error when inlining calls to
3925 unprototyped functions. */
3926 error ("incompatible type for argument %d of %qE", parmnum, rname);
3929 error ("incompatible types in assignment");
3932 error ("incompatible types in initialization");
3935 error ("incompatible types in return");
3941 return error_mark_node;
3944 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
3945 is used for error and waring reporting and indicates which argument
3946 is being processed. */
3949 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
3953 /* If FN was prototyped, the value has been converted already
3954 in convert_arguments. */
3955 if (!value || TYPE_ARG_TYPES (TREE_TYPE (fn)))
3958 type = TREE_TYPE (parm);
3959 ret = convert_for_assignment (type, value,
3960 ic_argpass_nonproto, fn,
3962 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
3963 && INTEGRAL_TYPE_P (type)
3964 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3965 ret = default_conversion (ret);
3969 /* If VALUE is a compound expr all of whose expressions are constant, then
3970 return its value. Otherwise, return error_mark_node.
3972 This is for handling COMPOUND_EXPRs as initializer elements
3973 which is allowed with a warning when -pedantic is specified. */
3976 valid_compound_expr_initializer (tree value, tree endtype)
3978 if (TREE_CODE (value) == COMPOUND_EXPR)
3980 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
3982 return error_mark_node;
3983 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
3986 else if (!initializer_constant_valid_p (value, endtype))
3987 return error_mark_node;
3992 /* Perform appropriate conversions on the initial value of a variable,
3993 store it in the declaration DECL,
3994 and print any error messages that are appropriate.
3995 If the init is invalid, store an ERROR_MARK. */
3998 store_init_value (tree decl, tree init)
4002 /* If variable's type was invalidly declared, just ignore it. */
4004 type = TREE_TYPE (decl);
4005 if (TREE_CODE (type) == ERROR_MARK)
4008 /* Digest the specified initializer into an expression. */
4010 value = digest_init (type, init, true, TREE_STATIC (decl));
4012 /* Store the expression if valid; else report error. */
4014 if (warn_traditional && !in_system_header
4015 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4016 warning (0, "traditional C rejects automatic aggregate initialization");
4018 DECL_INITIAL (decl) = value;
4020 /* ANSI wants warnings about out-of-range constant initializers. */
4021 STRIP_TYPE_NOPS (value);
4022 constant_expression_warning (value);
4024 /* Check if we need to set array size from compound literal size. */
4025 if (TREE_CODE (type) == ARRAY_TYPE
4026 && TYPE_DOMAIN (type) == 0
4027 && value != error_mark_node)
4029 tree inside_init = init;
4031 STRIP_TYPE_NOPS (inside_init);
4032 inside_init = fold (inside_init);
4034 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4036 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4038 if (TYPE_DOMAIN (TREE_TYPE (decl)))
4040 /* For int foo[] = (int [3]){1}; we need to set array size
4041 now since later on array initializer will be just the
4042 brace enclosed list of the compound literal. */
4043 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (decl));
4045 layout_decl (decl, 0);
4051 /* Methods for storing and printing names for error messages. */
4053 /* Implement a spelling stack that allows components of a name to be pushed
4054 and popped. Each element on the stack is this structure. */
4066 #define SPELLING_STRING 1
4067 #define SPELLING_MEMBER 2
4068 #define SPELLING_BOUNDS 3
4070 static struct spelling *spelling; /* Next stack element (unused). */
4071 static struct spelling *spelling_base; /* Spelling stack base. */
4072 static int spelling_size; /* Size of the spelling stack. */
4074 /* Macros to save and restore the spelling stack around push_... functions.
4075 Alternative to SAVE_SPELLING_STACK. */
4077 #define SPELLING_DEPTH() (spelling - spelling_base)
4078 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4080 /* Push an element on the spelling stack with type KIND and assign VALUE
4083 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4085 int depth = SPELLING_DEPTH (); \
4087 if (depth >= spelling_size) \
4089 spelling_size += 10; \
4090 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4092 RESTORE_SPELLING_DEPTH (depth); \
4095 spelling->kind = (KIND); \
4096 spelling->MEMBER = (VALUE); \
4100 /* Push STRING on the stack. Printed literally. */
4103 push_string (const char *string)
4105 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4108 /* Push a member name on the stack. Printed as '.' STRING. */
4111 push_member_name (tree decl)
4113 const char *const string
4114 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4115 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4118 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4121 push_array_bounds (int bounds)
4123 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4126 /* Compute the maximum size in bytes of the printed spelling. */
4129 spelling_length (void)
4134 for (p = spelling_base; p < spelling; p++)
4136 if (p->kind == SPELLING_BOUNDS)
4139 size += strlen (p->u.s) + 1;
4145 /* Print the spelling to BUFFER and return it. */
4148 print_spelling (char *buffer)
4153 for (p = spelling_base; p < spelling; p++)
4154 if (p->kind == SPELLING_BOUNDS)
4156 sprintf (d, "[%d]", p->u.i);
4162 if (p->kind == SPELLING_MEMBER)
4164 for (s = p->u.s; (*d = *s++); d++)
4171 /* Issue an error message for a bad initializer component.
4172 MSGID identifies the message.
4173 The component name is taken from the spelling stack. */
4176 error_init (const char *msgid)
4180 error ("%s", _(msgid));
4181 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4183 error ("(near initialization for %qs)", ofwhat);
4186 /* Issue a pedantic warning for a bad initializer component.
4187 MSGID identifies the message.
4188 The component name is taken from the spelling stack. */
4191 pedwarn_init (const char *msgid)
4195 pedwarn ("%s", _(msgid));
4196 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4198 pedwarn ("(near initialization for %qs)", ofwhat);
4201 /* Issue a warning for a bad initializer component.
4202 MSGID identifies the message.
4203 The component name is taken from the spelling stack. */
4206 warning_init (const char *msgid)
4210 warning (0, "%s", _(msgid));
4211 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4213 warning (0, "(near initialization for %qs)", ofwhat);
4216 /* If TYPE is an array type and EXPR is a parenthesized string
4217 constant, warn if pedantic that EXPR is being used to initialize an
4218 object of type TYPE. */
4221 maybe_warn_string_init (tree type, struct c_expr expr)
4224 && TREE_CODE (type) == ARRAY_TYPE
4225 && TREE_CODE (expr.value) == STRING_CST
4226 && expr.original_code != STRING_CST)
4227 pedwarn_init ("array initialized from parenthesized string constant");
4230 /* Digest the parser output INIT as an initializer for type TYPE.
4231 Return a C expression of type TYPE to represent the initial value.
4233 If INIT is a string constant, STRICT_STRING is true if it is
4234 unparenthesized or we should not warn here for it being parenthesized.
4235 For other types of INIT, STRICT_STRING is not used.
4237 REQUIRE_CONSTANT requests an error if non-constant initializers or
4238 elements are seen. */
4241 digest_init (tree type, tree init, bool strict_string, int require_constant)
4243 enum tree_code code = TREE_CODE (type);
4244 tree inside_init = init;
4246 if (type == error_mark_node
4247 || init == error_mark_node
4248 || TREE_TYPE (init) == error_mark_node)
4249 return error_mark_node;
4251 STRIP_TYPE_NOPS (inside_init);
4253 inside_init = fold (inside_init);
4255 /* Initialization of an array of chars from a string constant
4256 optionally enclosed in braces. */
4258 if (code == ARRAY_TYPE && inside_init
4259 && TREE_CODE (inside_init) == STRING_CST)
4261 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4262 /* Note that an array could be both an array of character type
4263 and an array of wchar_t if wchar_t is signed char or unsigned
4265 bool char_array = (typ1 == char_type_node
4266 || typ1 == signed_char_type_node
4267 || typ1 == unsigned_char_type_node);
4268 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4269 if (char_array || wchar_array)
4273 expr.value = inside_init;
4274 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4275 maybe_warn_string_init (type, expr);
4278 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4281 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4282 TYPE_MAIN_VARIANT (type)))
4285 if (!wchar_array && !char_string)
4287 error_init ("char-array initialized from wide string");
4288 return error_mark_node;
4290 if (char_string && !char_array)
4292 error_init ("wchar_t-array initialized from non-wide string");
4293 return error_mark_node;
4296 TREE_TYPE (inside_init) = type;
4297 if (TYPE_DOMAIN (type) != 0
4298 && TYPE_SIZE (type) != 0
4299 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4300 /* Subtract 1 (or sizeof (wchar_t))
4301 because it's ok to ignore the terminating null char
4302 that is counted in the length of the constant. */
4303 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4304 TREE_STRING_LENGTH (inside_init)
4305 - ((TYPE_PRECISION (typ1)
4306 != TYPE_PRECISION (char_type_node))
4307 ? (TYPE_PRECISION (wchar_type_node)
4310 pedwarn_init ("initializer-string for array of chars is too long");
4314 else if (INTEGRAL_TYPE_P (typ1))
4316 error_init ("array of inappropriate type initialized "
4317 "from string constant");
4318 return error_mark_node;
4322 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4323 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4324 below and handle as a constructor. */
4325 if (code == VECTOR_TYPE
4326 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4327 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4328 && TREE_CONSTANT (inside_init))
4330 if (TREE_CODE (inside_init) == VECTOR_CST
4331 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4332 TYPE_MAIN_VARIANT (type)))
4335 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4339 /* Iterate through elements and check if all constructor
4340 elements are *_CSTs. */
4341 for (link = CONSTRUCTOR_ELTS (inside_init);
4343 link = TREE_CHAIN (link))
4344 if (! CONSTANT_CLASS_P (TREE_VALUE (link)))
4348 return build_vector (type, CONSTRUCTOR_ELTS (inside_init));
4352 /* Any type can be initialized
4353 from an expression of the same type, optionally with braces. */
4355 if (inside_init && TREE_TYPE (inside_init) != 0
4356 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4357 TYPE_MAIN_VARIANT (type))
4358 || (code == ARRAY_TYPE
4359 && comptypes (TREE_TYPE (inside_init), type))
4360 || (code == VECTOR_TYPE
4361 && comptypes (TREE_TYPE (inside_init), type))
4362 || (code == POINTER_TYPE
4363 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4364 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4366 || (code == POINTER_TYPE
4367 && TREE_CODE (TREE_TYPE (inside_init)) == FUNCTION_TYPE
4368 && comptypes (TREE_TYPE (inside_init),
4369 TREE_TYPE (type)))))
4371 if (code == POINTER_TYPE)
4373 inside_init = default_function_array_conversion (inside_init);
4375 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4377 error_init ("invalid use of non-lvalue array");
4378 return error_mark_node;
4382 if (code == VECTOR_TYPE)
4383 /* Although the types are compatible, we may require a
4385 inside_init = convert (type, inside_init);
4387 if (require_constant && !flag_isoc99
4388 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4390 /* As an extension, allow initializing objects with static storage
4391 duration with compound literals (which are then treated just as
4392 the brace enclosed list they contain). */
4393 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4394 inside_init = DECL_INITIAL (decl);
4397 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4398 && TREE_CODE (inside_init) != CONSTRUCTOR)
4400 error_init ("array initialized from non-constant array expression");
4401 return error_mark_node;
4404 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4405 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4407 /* Compound expressions can only occur here if -pedantic or
4408 -pedantic-errors is specified. In the later case, we always want
4409 an error. In the former case, we simply want a warning. */
4410 if (require_constant && pedantic
4411 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4414 = valid_compound_expr_initializer (inside_init,
4415 TREE_TYPE (inside_init));
4416 if (inside_init == error_mark_node)
4417 error_init ("initializer element is not constant");
4419 pedwarn_init ("initializer element is not constant");
4420 if (flag_pedantic_errors)
4421 inside_init = error_mark_node;
4423 else if (require_constant
4424 && !initializer_constant_valid_p (inside_init,
4425 TREE_TYPE (inside_init)))
4427 error_init ("initializer element is not constant");
4428 inside_init = error_mark_node;
4434 /* Handle scalar types, including conversions. */
4436 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4437 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4438 || code == VECTOR_TYPE)
4440 /* Note that convert_for_assignment calls default_conversion
4441 for arrays and functions. We must not call it in the
4442 case where inside_init is a null pointer constant. */
4444 = convert_for_assignment (type, init, ic_init,
4445 NULL_TREE, NULL_TREE, 0);
4447 /* Check to see if we have already given an error message. */
4448 if (inside_init == error_mark_node)
4450 else if (require_constant && !TREE_CONSTANT (inside_init))
4452 error_init ("initializer element is not constant");
4453 inside_init = error_mark_node;
4455 else if (require_constant
4456 && !initializer_constant_valid_p (inside_init,
4457 TREE_TYPE (inside_init)))
4459 error_init ("initializer element is not computable at load time");
4460 inside_init = error_mark_node;
4466 /* Come here only for records and arrays. */
4468 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4470 error_init ("variable-sized object may not be initialized");
4471 return error_mark_node;
4474 error_init ("invalid initializer");
4475 return error_mark_node;
4478 /* Handle initializers that use braces. */
4480 /* Type of object we are accumulating a constructor for.
4481 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4482 static tree constructor_type;
4484 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4486 static tree constructor_fields;
4488 /* For an ARRAY_TYPE, this is the specified index
4489 at which to store the next element we get. */
4490 static tree constructor_index;
4492 /* For an ARRAY_TYPE, this is the maximum index. */
4493 static tree constructor_max_index;
4495 /* For a RECORD_TYPE, this is the first field not yet written out. */
4496 static tree constructor_unfilled_fields;
4498 /* For an ARRAY_TYPE, this is the index of the first element
4499 not yet written out. */
4500 static tree constructor_unfilled_index;
4502 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4503 This is so we can generate gaps between fields, when appropriate. */
4504 static tree constructor_bit_index;
4506 /* If we are saving up the elements rather than allocating them,
4507 this is the list of elements so far (in reverse order,
4508 most recent first). */
4509 static tree constructor_elements;
4511 /* 1 if constructor should be incrementally stored into a constructor chain,
4512 0 if all the elements should be kept in AVL tree. */
4513 static int constructor_incremental;
4515 /* 1 if so far this constructor's elements are all compile-time constants. */
4516 static int constructor_constant;
4518 /* 1 if so far this constructor's elements are all valid address constants. */
4519 static int constructor_simple;
4521 /* 1 if this constructor is erroneous so far. */
4522 static int constructor_erroneous;
4524 /* Structure for managing pending initializer elements, organized as an
4529 struct init_node *left, *right;
4530 struct init_node *parent;
4536 /* Tree of pending elements at this constructor level.
4537 These are elements encountered out of order
4538 which belong at places we haven't reached yet in actually
4540 Will never hold tree nodes across GC runs. */
4541 static struct init_node *constructor_pending_elts;
4543 /* The SPELLING_DEPTH of this constructor. */
4544 static int constructor_depth;
4546 /* DECL node for which an initializer is being read.
4547 0 means we are reading a constructor expression
4548 such as (struct foo) {...}. */
4549 static tree constructor_decl;
4551 /* Nonzero if this is an initializer for a top-level decl. */
4552 static int constructor_top_level;
4554 /* Nonzero if there were any member designators in this initializer. */
4555 static int constructor_designated;
4557 /* Nesting depth of designator list. */
4558 static int designator_depth;
4560 /* Nonzero if there were diagnosed errors in this designator list. */
4561 static int designator_errorneous;
4564 /* This stack has a level for each implicit or explicit level of
4565 structuring in the initializer, including the outermost one. It
4566 saves the values of most of the variables above. */
4568 struct constructor_range_stack;
4570 struct constructor_stack
4572 struct constructor_stack *next;
4577 tree unfilled_index;
4578 tree unfilled_fields;
4581 struct init_node *pending_elts;
4584 /* If value nonzero, this value should replace the entire
4585 constructor at this level. */
4586 struct c_expr replacement_value;
4587 struct constructor_range_stack *range_stack;
4597 static struct constructor_stack *constructor_stack;
4599 /* This stack represents designators from some range designator up to
4600 the last designator in the list. */
4602 struct constructor_range_stack
4604 struct constructor_range_stack *next, *prev;
4605 struct constructor_stack *stack;
4612 static struct constructor_range_stack *constructor_range_stack;
4614 /* This stack records separate initializers that are nested.
4615 Nested initializers can't happen in ANSI C, but GNU C allows them
4616 in cases like { ... (struct foo) { ... } ... }. */
4618 struct initializer_stack
4620 struct initializer_stack *next;
4622 struct constructor_stack *constructor_stack;
4623 struct constructor_range_stack *constructor_range_stack;
4625 struct spelling *spelling;
4626 struct spelling *spelling_base;
4629 char require_constant_value;
4630 char require_constant_elements;
4633 static struct initializer_stack *initializer_stack;
4635 /* Prepare to parse and output the initializer for variable DECL. */
4638 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4641 struct initializer_stack *p = xmalloc (sizeof (struct initializer_stack));
4643 p->decl = constructor_decl;
4644 p->require_constant_value = require_constant_value;
4645 p->require_constant_elements = require_constant_elements;
4646 p->constructor_stack = constructor_stack;
4647 p->constructor_range_stack = constructor_range_stack;
4648 p->elements = constructor_elements;
4649 p->spelling = spelling;
4650 p->spelling_base = spelling_base;
4651 p->spelling_size = spelling_size;
4652 p->top_level = constructor_top_level;
4653 p->next = initializer_stack;
4654 initializer_stack = p;
4656 constructor_decl = decl;
4657 constructor_designated = 0;
4658 constructor_top_level = top_level;
4660 if (decl != 0 && decl != error_mark_node)
4662 require_constant_value = TREE_STATIC (decl);
4663 require_constant_elements
4664 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4665 /* For a scalar, you can always use any value to initialize,
4666 even within braces. */
4667 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4668 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4669 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4670 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4671 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4675 require_constant_value = 0;
4676 require_constant_elements = 0;
4677 locus = "(anonymous)";
4680 constructor_stack = 0;
4681 constructor_range_stack = 0;
4683 missing_braces_mentioned = 0;
4687 RESTORE_SPELLING_DEPTH (0);
4690 push_string (locus);
4696 struct initializer_stack *p = initializer_stack;
4698 /* Free the whole constructor stack of this initializer. */
4699 while (constructor_stack)
4701 struct constructor_stack *q = constructor_stack;
4702 constructor_stack = q->next;
4706 gcc_assert (!constructor_range_stack);
4708 /* Pop back to the data of the outer initializer (if any). */
4709 free (spelling_base);
4711 constructor_decl = p->decl;
4712 require_constant_value = p->require_constant_value;
4713 require_constant_elements = p->require_constant_elements;
4714 constructor_stack = p->constructor_stack;
4715 constructor_range_stack = p->constructor_range_stack;
4716 constructor_elements = p->elements;
4717 spelling = p->spelling;
4718 spelling_base = p->spelling_base;
4719 spelling_size = p->spelling_size;
4720 constructor_top_level = p->top_level;
4721 initializer_stack = p->next;
4725 /* Call here when we see the initializer is surrounded by braces.
4726 This is instead of a call to push_init_level;
4727 it is matched by a call to pop_init_level.
4729 TYPE is the type to initialize, for a constructor expression.
4730 For an initializer for a decl, TYPE is zero. */
4733 really_start_incremental_init (tree type)
4735 struct constructor_stack *p = XNEW (struct constructor_stack);
4738 type = TREE_TYPE (constructor_decl);
4740 if (targetm.vector_opaque_p (type))
4741 error ("opaque vector types cannot be initialized");
4743 p->type = constructor_type;
4744 p->fields = constructor_fields;
4745 p->index = constructor_index;
4746 p->max_index = constructor_max_index;
4747 p->unfilled_index = constructor_unfilled_index;
4748 p->unfilled_fields = constructor_unfilled_fields;
4749 p->bit_index = constructor_bit_index;
4750 p->elements = constructor_elements;
4751 p->constant = constructor_constant;
4752 p->simple = constructor_simple;
4753 p->erroneous = constructor_erroneous;
4754 p->pending_elts = constructor_pending_elts;
4755 p->depth = constructor_depth;
4756 p->replacement_value.value = 0;
4757 p->replacement_value.original_code = ERROR_MARK;
4761 p->incremental = constructor_incremental;
4762 p->designated = constructor_designated;
4764 constructor_stack = p;
4766 constructor_constant = 1;
4767 constructor_simple = 1;
4768 constructor_depth = SPELLING_DEPTH ();
4769 constructor_elements = 0;
4770 constructor_pending_elts = 0;
4771 constructor_type = type;
4772 constructor_incremental = 1;
4773 constructor_designated = 0;
4774 designator_depth = 0;
4775 designator_errorneous = 0;
4777 if (TREE_CODE (constructor_type) == RECORD_TYPE
4778 || TREE_CODE (constructor_type) == UNION_TYPE)
4780 constructor_fields = TYPE_FIELDS (constructor_type);
4781 /* Skip any nameless bit fields at the beginning. */
4782 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4783 && DECL_NAME (constructor_fields) == 0)
4784 constructor_fields = TREE_CHAIN (constructor_fields);
4786 constructor_unfilled_fields = constructor_fields;
4787 constructor_bit_index = bitsize_zero_node;
4789 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4791 if (TYPE_DOMAIN (constructor_type))
4793 constructor_max_index
4794 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4796 /* Detect non-empty initializations of zero-length arrays. */
4797 if (constructor_max_index == NULL_TREE
4798 && TYPE_SIZE (constructor_type))
4799 constructor_max_index = build_int_cst (NULL_TREE, -1);
4801 /* constructor_max_index needs to be an INTEGER_CST. Attempts
4802 to initialize VLAs will cause a proper error; avoid tree
4803 checking errors as well by setting a safe value. */
4804 if (constructor_max_index
4805 && TREE_CODE (constructor_max_index) != INTEGER_CST)
4806 constructor_max_index = build_int_cst (NULL_TREE, -1);
4809 = convert (bitsizetype,
4810 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
4814 constructor_index = bitsize_zero_node;
4815 constructor_max_index = NULL_TREE;
4818 constructor_unfilled_index = constructor_index;
4820 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4822 /* Vectors are like simple fixed-size arrays. */
4823 constructor_max_index =
4824 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4825 constructor_index = convert (bitsizetype, bitsize_zero_node);
4826 constructor_unfilled_index = constructor_index;
4830 /* Handle the case of int x = {5}; */
4831 constructor_fields = constructor_type;
4832 constructor_unfilled_fields = constructor_type;
4836 /* Push down into a subobject, for initialization.
4837 If this is for an explicit set of braces, IMPLICIT is 0.
4838 If it is because the next element belongs at a lower level,
4839 IMPLICIT is 1 (or 2 if the push is because of designator list). */
4842 push_init_level (int implicit)
4844 struct constructor_stack *p;
4845 tree value = NULL_TREE;
4847 /* If we've exhausted any levels that didn't have braces,
4848 pop them now. If implicit == 1, this will have been done in
4849 process_init_element; do not repeat it here because in the case
4850 of excess initializers for an empty aggregate this leads to an
4851 infinite cycle of popping a level and immediately recreating
4855 while (constructor_stack->implicit)
4857 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4858 || TREE_CODE (constructor_type) == UNION_TYPE)
4859 && constructor_fields == 0)
4860 process_init_element (pop_init_level (1));
4861 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
4862 && constructor_max_index
4863 && tree_int_cst_lt (constructor_max_index,
4865 process_init_element (pop_init_level (1));
4871 /* Unless this is an explicit brace, we need to preserve previous
4875 if ((TREE_CODE (constructor_type) == RECORD_TYPE
4876 || TREE_CODE (constructor_type) == UNION_TYPE)
4877 && constructor_fields)
4878 value = find_init_member (constructor_fields);
4879 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4880 value = find_init_member (constructor_index);
4883 p = XNEW (struct constructor_stack);
4884 p->type = constructor_type;
4885 p->fields = constructor_fields;
4886 p->index = constructor_index;
4887 p->max_index = constructor_max_index;
4888 p->unfilled_index = constructor_unfilled_index;
4889 p->unfilled_fields = constructor_unfilled_fields;
4890 p->bit_index = constructor_bit_index;
4891 p->elements = constructor_elements;
4892 p->constant = constructor_constant;
4893 p->simple = constructor_simple;
4894 p->erroneous = constructor_erroneous;
4895 p->pending_elts = constructor_pending_elts;
4896 p->depth = constructor_depth;
4897 p->replacement_value.value = 0;
4898 p->replacement_value.original_code = ERROR_MARK;
4899 p->implicit = implicit;
4901 p->incremental = constructor_incremental;
4902 p->designated = constructor_designated;
4903 p->next = constructor_stack;
4905 constructor_stack = p;
4907 constructor_constant = 1;
4908 constructor_simple = 1;
4909 constructor_depth = SPELLING_DEPTH ();
4910 constructor_elements = 0;
4911 constructor_incremental = 1;
4912 constructor_designated = 0;
4913 constructor_pending_elts = 0;
4916 p->range_stack = constructor_range_stack;
4917 constructor_range_stack = 0;
4918 designator_depth = 0;
4919 designator_errorneous = 0;
4922 /* Don't die if an entire brace-pair level is superfluous
4923 in the containing level. */
4924 if (constructor_type == 0)
4926 else if (TREE_CODE (constructor_type) == RECORD_TYPE
4927 || TREE_CODE (constructor_type) == UNION_TYPE)
4929 /* Don't die if there are extra init elts at the end. */
4930 if (constructor_fields == 0)
4931 constructor_type = 0;
4934 constructor_type = TREE_TYPE (constructor_fields);
4935 push_member_name (constructor_fields);
4936 constructor_depth++;
4939 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4941 constructor_type = TREE_TYPE (constructor_type);
4942 push_array_bounds (tree_low_cst (constructor_index, 0));
4943 constructor_depth++;
4946 if (constructor_type == 0)
4948 error_init ("extra brace group at end of initializer");
4949 constructor_fields = 0;
4950 constructor_unfilled_fields = 0;
4954 if (value && TREE_CODE (value) == CONSTRUCTOR)
4956 constructor_constant = TREE_CONSTANT (value);
4957 constructor_simple = TREE_STATIC (value);
4958 constructor_elements = CONSTRUCTOR_ELTS (value);
4959 if (constructor_elements
4960 && (TREE_CODE (constructor_type) == RECORD_TYPE
4961 || TREE_CODE (constructor_type) == ARRAY_TYPE))
4962 set_nonincremental_init ();
4965 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
4967 missing_braces_mentioned = 1;
4968 warning_init ("missing braces around initializer");
4971 if (TREE_CODE (constructor_type) == RECORD_TYPE
4972 || TREE_CODE (constructor_type) == UNION_TYPE)
4974 constructor_fields = TYPE_FIELDS (constructor_type);
4975 /* Skip any nameless bit fields at the beginning. */
4976 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
4977 && DECL_NAME (constructor_fields) == 0)
4978 constructor_fields = TREE_CHAIN (constructor_fields);
4980 constructor_unfilled_fields = constructor_fields;
4981 constructor_bit_index = bitsize_zero_node;
4983 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
4985 /* Vectors are like simple fixed-size arrays. */
4986 constructor_max_index =
4987 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
4988 constructor_index = convert (bitsizetype, integer_zero_node);
4989 constructor_unfilled_index = constructor_index;
4991 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
4993 if (TYPE_DOMAIN (constructor_type))
4995 constructor_max_index
4996 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
4998 /* Detect non-empty initializations of zero-length arrays. */
4999 if (constructor_max_index == NULL_TREE
5000 && TYPE_SIZE (constructor_type))
5001 constructor_max_index = build_int_cst (NULL_TREE, -1);
5003 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5004 to initialize VLAs will cause a proper error; avoid tree
5005 checking errors as well by setting a safe value. */
5006 if (constructor_max_index
5007 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5008 constructor_max_index = build_int_cst (NULL_TREE, -1);
5011 = convert (bitsizetype,
5012 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5015 constructor_index = bitsize_zero_node;
5017 constructor_unfilled_index = constructor_index;
5018 if (value && TREE_CODE (value) == STRING_CST)
5020 /* We need to split the char/wchar array into individual
5021 characters, so that we don't have to special case it
5023 set_nonincremental_init_from_string (value);
5028 if (constructor_type != error_mark_node)
5029 warning_init ("braces around scalar initializer");
5030 constructor_fields = constructor_type;
5031 constructor_unfilled_fields = constructor_type;
5035 /* At the end of an implicit or explicit brace level,
5036 finish up that level of constructor. If a single expression
5037 with redundant braces initialized that level, return the
5038 c_expr structure for that expression. Otherwise, the original_code
5039 element is set to ERROR_MARK.
5040 If we were outputting the elements as they are read, return 0 as the value
5041 from inner levels (process_init_element ignores that),
5042 but return error_mark_node as the value from the outermost level
5043 (that's what we want to put in DECL_INITIAL).
5044 Otherwise, return a CONSTRUCTOR expression as the value. */
5047 pop_init_level (int implicit)
5049 struct constructor_stack *p;
5052 ret.original_code = ERROR_MARK;
5056 /* When we come to an explicit close brace,
5057 pop any inner levels that didn't have explicit braces. */
5058 while (constructor_stack->implicit)
5059 process_init_element (pop_init_level (1));
5061 gcc_assert (!constructor_range_stack);
5064 /* Now output all pending elements. */
5065 constructor_incremental = 1;
5066 output_pending_init_elements (1);
5068 p = constructor_stack;
5070 /* Error for initializing a flexible array member, or a zero-length
5071 array member in an inappropriate context. */
5072 if (constructor_type && constructor_fields
5073 && TREE_CODE (constructor_type) == ARRAY_TYPE
5074 && TYPE_DOMAIN (constructor_type)
5075 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5077 /* Silently discard empty initializations. The parser will
5078 already have pedwarned for empty brackets. */
5079 if (integer_zerop (constructor_unfilled_index))
5080 constructor_type = NULL_TREE;
5083 gcc_assert (!TYPE_SIZE (constructor_type));
5085 if (constructor_depth > 2)
5086 error_init ("initialization of flexible array member in a nested context");
5088 pedwarn_init ("initialization of a flexible array member");
5090 /* We have already issued an error message for the existence
5091 of a flexible array member not at the end of the structure.
5092 Discard the initializer so that we do not die later. */
5093 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5094 constructor_type = NULL_TREE;
5098 /* Warn when some struct elements are implicitly initialized to zero. */
5099 if (warn_missing_field_initializers
5101 && TREE_CODE (constructor_type) == RECORD_TYPE
5102 && constructor_unfilled_fields)
5104 /* Do not warn for flexible array members or zero-length arrays. */
5105 while (constructor_unfilled_fields
5106 && (!DECL_SIZE (constructor_unfilled_fields)
5107 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5108 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5110 /* Do not warn if this level of the initializer uses member
5111 designators; it is likely to be deliberate. */
5112 if (constructor_unfilled_fields && !constructor_designated)
5114 push_member_name (constructor_unfilled_fields);
5115 warning_init ("missing initializer");
5116 RESTORE_SPELLING_DEPTH (constructor_depth);
5120 /* Pad out the end of the structure. */
5121 if (p->replacement_value.value)
5122 /* If this closes a superfluous brace pair,
5123 just pass out the element between them. */
5124 ret = p->replacement_value;
5125 else if (constructor_type == 0)
5127 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5128 && TREE_CODE (constructor_type) != UNION_TYPE
5129 && TREE_CODE (constructor_type) != ARRAY_TYPE
5130 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5132 /* A nonincremental scalar initializer--just return
5133 the element, after verifying there is just one. */
5134 if (constructor_elements == 0)
5136 if (!constructor_erroneous)
5137 error_init ("empty scalar initializer");
5138 ret.value = error_mark_node;
5140 else if (TREE_CHAIN (constructor_elements) != 0)
5142 error_init ("extra elements in scalar initializer");
5143 ret.value = TREE_VALUE (constructor_elements);
5146 ret.value = TREE_VALUE (constructor_elements);
5150 if (constructor_erroneous)
5151 ret.value = error_mark_node;
5154 ret.value = build_constructor (constructor_type,
5155 nreverse (constructor_elements));
5156 if (constructor_constant)
5157 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5158 if (constructor_constant && constructor_simple)
5159 TREE_STATIC (ret.value) = 1;
5163 constructor_type = p->type;
5164 constructor_fields = p->fields;
5165 constructor_index = p->index;
5166 constructor_max_index = p->max_index;
5167 constructor_unfilled_index = p->unfilled_index;
5168 constructor_unfilled_fields = p->unfilled_fields;
5169 constructor_bit_index = p->bit_index;
5170 constructor_elements = p->elements;
5171 constructor_constant = p->constant;
5172 constructor_simple = p->simple;
5173 constructor_erroneous = p->erroneous;
5174 constructor_incremental = p->incremental;
5175 constructor_designated = p->designated;
5176 constructor_pending_elts = p->pending_elts;
5177 constructor_depth = p->depth;
5179 constructor_range_stack = p->range_stack;
5180 RESTORE_SPELLING_DEPTH (constructor_depth);
5182 constructor_stack = p->next;
5187 if (constructor_stack == 0)
5189 ret.value = error_mark_node;
5197 /* Common handling for both array range and field name designators.
5198 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5201 set_designator (int array)
5204 enum tree_code subcode;
5206 /* Don't die if an entire brace-pair level is superfluous
5207 in the containing level. */
5208 if (constructor_type == 0)
5211 /* If there were errors in this designator list already, bail out
5213 if (designator_errorneous)
5216 if (!designator_depth)
5218 gcc_assert (!constructor_range_stack);
5220 /* Designator list starts at the level of closest explicit
5222 while (constructor_stack->implicit)
5223 process_init_element (pop_init_level (1));
5224 constructor_designated = 1;
5228 switch (TREE_CODE (constructor_type))
5232 subtype = TREE_TYPE (constructor_fields);
5233 if (subtype != error_mark_node)
5234 subtype = TYPE_MAIN_VARIANT (subtype);
5237 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5243 subcode = TREE_CODE (subtype);
5244 if (array && subcode != ARRAY_TYPE)
5246 error_init ("array index in non-array initializer");
5249 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5251 error_init ("field name not in record or union initializer");
5255 constructor_designated = 1;
5256 push_init_level (2);
5260 /* If there are range designators in designator list, push a new designator
5261 to constructor_range_stack. RANGE_END is end of such stack range or
5262 NULL_TREE if there is no range designator at this level. */
5265 push_range_stack (tree range_end)
5267 struct constructor_range_stack *p;
5269 p = GGC_NEW (struct constructor_range_stack);
5270 p->prev = constructor_range_stack;
5272 p->fields = constructor_fields;
5273 p->range_start = constructor_index;
5274 p->index = constructor_index;
5275 p->stack = constructor_stack;
5276 p->range_end = range_end;
5277 if (constructor_range_stack)
5278 constructor_range_stack->next = p;
5279 constructor_range_stack = p;
5282 /* Within an array initializer, specify the next index to be initialized.
5283 FIRST is that index. If LAST is nonzero, then initialize a range
5284 of indices, running from FIRST through LAST. */
5287 set_init_index (tree first, tree last)
5289 if (set_designator (1))
5292 designator_errorneous = 1;
5294 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5295 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5297 error_init ("array index in initializer not of integer type");
5301 if (TREE_CODE (first) != INTEGER_CST)
5302 error_init ("nonconstant array index in initializer");
5303 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5304 error_init ("nonconstant array index in initializer");
5305 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5306 error_init ("array index in non-array initializer");
5307 else if (tree_int_cst_sgn (first) == -1)
5308 error_init ("array index in initializer exceeds array bounds");
5309 else if (constructor_max_index
5310 && tree_int_cst_lt (constructor_max_index, first))
5311 error_init ("array index in initializer exceeds array bounds");
5314 constructor_index = convert (bitsizetype, first);
5318 if (tree_int_cst_equal (first, last))
5320 else if (tree_int_cst_lt (last, first))
5322 error_init ("empty index range in initializer");
5327 last = convert (bitsizetype, last);
5328 if (constructor_max_index != 0
5329 && tree_int_cst_lt (constructor_max_index, last))
5331 error_init ("array index range in initializer exceeds array bounds");
5338 designator_errorneous = 0;
5339 if (constructor_range_stack || last)
5340 push_range_stack (last);
5344 /* Within a struct initializer, specify the next field to be initialized. */
5347 set_init_label (tree fieldname)
5351 if (set_designator (0))
5354 designator_errorneous = 1;
5356 if (TREE_CODE (constructor_type) != RECORD_TYPE
5357 && TREE_CODE (constructor_type) != UNION_TYPE)
5359 error_init ("field name not in record or union initializer");
5363 for (tail = TYPE_FIELDS (constructor_type); tail;
5364 tail = TREE_CHAIN (tail))
5366 if (DECL_NAME (tail) == fieldname)
5371 error ("unknown field %qE specified in initializer", fieldname);
5374 constructor_fields = tail;
5376 designator_errorneous = 0;
5377 if (constructor_range_stack)
5378 push_range_stack (NULL_TREE);
5382 /* Add a new initializer to the tree of pending initializers. PURPOSE
5383 identifies the initializer, either array index or field in a structure.
5384 VALUE is the value of that index or field. */
5387 add_pending_init (tree purpose, tree value)
5389 struct init_node *p, **q, *r;
5391 q = &constructor_pending_elts;
5394 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5399 if (tree_int_cst_lt (purpose, p->purpose))
5401 else if (tree_int_cst_lt (p->purpose, purpose))
5405 if (TREE_SIDE_EFFECTS (p->value))
5406 warning_init ("initialized field with side-effects overwritten");
5416 bitpos = bit_position (purpose);
5420 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5422 else if (p->purpose != purpose)
5426 if (TREE_SIDE_EFFECTS (p->value))
5427 warning_init ("initialized field with side-effects overwritten");
5434 r = GGC_NEW (struct init_node);
5435 r->purpose = purpose;
5446 struct init_node *s;
5450 if (p->balance == 0)
5452 else if (p->balance < 0)
5459 p->left->parent = p;
5476 constructor_pending_elts = r;
5481 struct init_node *t = r->right;
5485 r->right->parent = r;
5490 p->left->parent = p;
5493 p->balance = t->balance < 0;
5494 r->balance = -(t->balance > 0);
5509 constructor_pending_elts = t;
5515 /* p->balance == +1; growth of left side balances the node. */
5520 else /* r == p->right */
5522 if (p->balance == 0)
5523 /* Growth propagation from right side. */
5525 else if (p->balance > 0)
5532 p->right->parent = p;
5549 constructor_pending_elts = r;
5551 else /* r->balance == -1 */
5554 struct init_node *t = r->left;
5558 r->left->parent = r;
5563 p->right->parent = p;
5566 r->balance = (t->balance < 0);
5567 p->balance = -(t->balance > 0);
5582 constructor_pending_elts = t;
5588 /* p->balance == -1; growth of right side balances the node. */
5599 /* Build AVL tree from a sorted chain. */
5602 set_nonincremental_init (void)
5606 if (TREE_CODE (constructor_type) != RECORD_TYPE
5607 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5610 for (chain = constructor_elements; chain; chain = TREE_CHAIN (chain))
5611 add_pending_init (TREE_PURPOSE (chain), TREE_VALUE (chain));
5612 constructor_elements = 0;
5613 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5615 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5616 /* Skip any nameless bit fields at the beginning. */
5617 while (constructor_unfilled_fields != 0
5618 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5619 && DECL_NAME (constructor_unfilled_fields) == 0)
5620 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5623 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5625 if (TYPE_DOMAIN (constructor_type))
5626 constructor_unfilled_index
5627 = convert (bitsizetype,
5628 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5630 constructor_unfilled_index = bitsize_zero_node;
5632 constructor_incremental = 0;
5635 /* Build AVL tree from a string constant. */
5638 set_nonincremental_init_from_string (tree str)
5640 tree value, purpose, type;
5641 HOST_WIDE_INT val[2];
5642 const char *p, *end;
5643 int byte, wchar_bytes, charwidth, bitpos;
5645 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5647 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5648 == TYPE_PRECISION (char_type_node))
5652 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5653 == TYPE_PRECISION (wchar_type_node));
5654 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5656 charwidth = TYPE_PRECISION (char_type_node);
5657 type = TREE_TYPE (constructor_type);
5658 p = TREE_STRING_POINTER (str);
5659 end = p + TREE_STRING_LENGTH (str);
5661 for (purpose = bitsize_zero_node;
5662 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5663 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5665 if (wchar_bytes == 1)
5667 val[1] = (unsigned char) *p++;
5674 for (byte = 0; byte < wchar_bytes; byte++)
5676 if (BYTES_BIG_ENDIAN)
5677 bitpos = (wchar_bytes - byte - 1) * charwidth;
5679 bitpos = byte * charwidth;
5680 val[bitpos < HOST_BITS_PER_WIDE_INT]
5681 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5682 << (bitpos % HOST_BITS_PER_WIDE_INT);
5686 if (!TYPE_UNSIGNED (type))
5688 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5689 if (bitpos < HOST_BITS_PER_WIDE_INT)
5691 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5693 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5697 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5702 else if (val[0] & (((HOST_WIDE_INT) 1)
5703 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5704 val[0] |= ((HOST_WIDE_INT) -1)
5705 << (bitpos - HOST_BITS_PER_WIDE_INT);
5708 value = build_int_cst_wide (type, val[1], val[0]);
5709 add_pending_init (purpose, value);
5712 constructor_incremental = 0;
5715 /* Return value of FIELD in pending initializer or zero if the field was
5716 not initialized yet. */
5719 find_init_member (tree field)
5721 struct init_node *p;
5723 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5725 if (constructor_incremental
5726 && tree_int_cst_lt (field, constructor_unfilled_index))
5727 set_nonincremental_init ();
5729 p = constructor_pending_elts;
5732 if (tree_int_cst_lt (field, p->purpose))
5734 else if (tree_int_cst_lt (p->purpose, field))
5740 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5742 tree bitpos = bit_position (field);
5744 if (constructor_incremental
5745 && (!constructor_unfilled_fields
5746 || tree_int_cst_lt (bitpos,
5747 bit_position (constructor_unfilled_fields))))
5748 set_nonincremental_init ();
5750 p = constructor_pending_elts;
5753 if (field == p->purpose)
5755 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5761 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5763 if (constructor_elements
5764 && TREE_PURPOSE (constructor_elements) == field)
5765 return TREE_VALUE (constructor_elements);
5770 /* "Output" the next constructor element.
5771 At top level, really output it to assembler code now.
5772 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
5773 TYPE is the data type that the containing data type wants here.
5774 FIELD is the field (a FIELD_DECL) or the index that this element fills.
5775 If VALUE is a string constant, STRICT_STRING is true if it is
5776 unparenthesized or we should not warn here for it being parenthesized.
5777 For other types of VALUE, STRICT_STRING is not used.
5779 PENDING if non-nil means output pending elements that belong
5780 right after this element. (PENDING is normally 1;
5781 it is 0 while outputting pending elements, to avoid recursion.) */
5784 output_init_element (tree value, bool strict_string, tree type, tree field,
5787 if (type == error_mark_node || value == error_mark_node)
5789 constructor_erroneous = 1;
5792 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
5793 || (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
5794 && !(TREE_CODE (value) == STRING_CST
5795 && TREE_CODE (type) == ARRAY_TYPE
5796 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
5797 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
5798 TYPE_MAIN_VARIANT (type))))
5799 value = default_conversion (value);
5801 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
5802 && require_constant_value && !flag_isoc99 && pending)
5804 /* As an extension, allow initializing objects with static storage
5805 duration with compound literals (which are then treated just as
5806 the brace enclosed list they contain). */
5807 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
5808 value = DECL_INITIAL (decl);
5811 if (value == error_mark_node)
5812 constructor_erroneous = 1;
5813 else if (!TREE_CONSTANT (value))
5814 constructor_constant = 0;
5815 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
5816 || ((TREE_CODE (constructor_type) == RECORD_TYPE
5817 || TREE_CODE (constructor_type) == UNION_TYPE)
5818 && DECL_C_BIT_FIELD (field)
5819 && TREE_CODE (value) != INTEGER_CST))
5820 constructor_simple = 0;
5822 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
5824 if (require_constant_value)
5826 error_init ("initializer element is not constant");
5827 value = error_mark_node;
5829 else if (require_constant_elements)
5830 pedwarn ("initializer element is not computable at load time");
5833 /* If this field is empty (and not at the end of structure),
5834 don't do anything other than checking the initializer. */
5836 && (TREE_TYPE (field) == error_mark_node
5837 || (COMPLETE_TYPE_P (TREE_TYPE (field))
5838 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
5839 && (TREE_CODE (constructor_type) == ARRAY_TYPE
5840 || TREE_CHAIN (field)))))
5843 value = digest_init (type, value, strict_string, require_constant_value);
5844 if (value == error_mark_node)
5846 constructor_erroneous = 1;
5850 /* If this element doesn't come next in sequence,
5851 put it on constructor_pending_elts. */
5852 if (TREE_CODE (constructor_type) == ARRAY_TYPE
5853 && (!constructor_incremental
5854 || !tree_int_cst_equal (field, constructor_unfilled_index)))
5856 if (constructor_incremental
5857 && tree_int_cst_lt (field, constructor_unfilled_index))
5858 set_nonincremental_init ();
5860 add_pending_init (field, value);
5863 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5864 && (!constructor_incremental
5865 || field != constructor_unfilled_fields))
5867 /* We do this for records but not for unions. In a union,
5868 no matter which field is specified, it can be initialized
5869 right away since it starts at the beginning of the union. */
5870 if (constructor_incremental)
5872 if (!constructor_unfilled_fields)
5873 set_nonincremental_init ();
5876 tree bitpos, unfillpos;
5878 bitpos = bit_position (field);
5879 unfillpos = bit_position (constructor_unfilled_fields);
5881 if (tree_int_cst_lt (bitpos, unfillpos))
5882 set_nonincremental_init ();
5886 add_pending_init (field, value);
5889 else if (TREE_CODE (constructor_type) == UNION_TYPE
5890 && constructor_elements)
5892 if (TREE_SIDE_EFFECTS (TREE_VALUE (constructor_elements)))
5893 warning_init ("initialized field with side-effects overwritten");
5895 /* We can have just one union field set. */
5896 constructor_elements = 0;
5899 /* Otherwise, output this element either to
5900 constructor_elements or to the assembler file. */
5902 if (field && TREE_CODE (field) == INTEGER_CST)
5903 field = copy_node (field);
5904 constructor_elements
5905 = tree_cons (field, value, constructor_elements);
5907 /* Advance the variable that indicates sequential elements output. */
5908 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5909 constructor_unfilled_index
5910 = size_binop (PLUS_EXPR, constructor_unfilled_index,
5912 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
5914 constructor_unfilled_fields
5915 = TREE_CHAIN (constructor_unfilled_fields);
5917 /* Skip any nameless bit fields. */
5918 while (constructor_unfilled_fields != 0
5919 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5920 && DECL_NAME (constructor_unfilled_fields) == 0)
5921 constructor_unfilled_fields =
5922 TREE_CHAIN (constructor_unfilled_fields);
5924 else if (TREE_CODE (constructor_type) == UNION_TYPE)
5925 constructor_unfilled_fields = 0;
5927 /* Now output any pending elements which have become next. */
5929 output_pending_init_elements (0);
5932 /* Output any pending elements which have become next.
5933 As we output elements, constructor_unfilled_{fields,index}
5934 advances, which may cause other elements to become next;
5935 if so, they too are output.
5937 If ALL is 0, we return when there are
5938 no more pending elements to output now.
5940 If ALL is 1, we output space as necessary so that
5941 we can output all the pending elements. */
5944 output_pending_init_elements (int all)
5946 struct init_node *elt = constructor_pending_elts;
5951 /* Look through the whole pending tree.
5952 If we find an element that should be output now,
5953 output it. Otherwise, set NEXT to the element
5954 that comes first among those still pending. */
5959 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5961 if (tree_int_cst_equal (elt->purpose,
5962 constructor_unfilled_index))
5963 output_init_element (elt->value, true,
5964 TREE_TYPE (constructor_type),
5965 constructor_unfilled_index, 0);
5966 else if (tree_int_cst_lt (constructor_unfilled_index,
5969 /* Advance to the next smaller node. */
5974 /* We have reached the smallest node bigger than the
5975 current unfilled index. Fill the space first. */
5976 next = elt->purpose;
5982 /* Advance to the next bigger node. */
5987 /* We have reached the biggest node in a subtree. Find
5988 the parent of it, which is the next bigger node. */
5989 while (elt->parent && elt->parent->right == elt)
5992 if (elt && tree_int_cst_lt (constructor_unfilled_index,
5995 next = elt->purpose;
6001 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6002 || TREE_CODE (constructor_type) == UNION_TYPE)
6004 tree ctor_unfilled_bitpos, elt_bitpos;
6006 /* If the current record is complete we are done. */
6007 if (constructor_unfilled_fields == 0)
6010 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6011 elt_bitpos = bit_position (elt->purpose);
6012 /* We can't compare fields here because there might be empty
6013 fields in between. */
6014 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6016 constructor_unfilled_fields = elt->purpose;
6017 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6020 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6022 /* Advance to the next smaller node. */
6027 /* We have reached the smallest node bigger than the
6028 current unfilled field. Fill the space first. */
6029 next = elt->purpose;
6035 /* Advance to the next bigger node. */
6040 /* We have reached the biggest node in a subtree. Find
6041 the parent of it, which is the next bigger node. */
6042 while (elt->parent && elt->parent->right == elt)
6046 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6047 bit_position (elt->purpose))))
6049 next = elt->purpose;
6057 /* Ordinarily return, but not if we want to output all
6058 and there are elements left. */
6059 if (!(all && next != 0))
6062 /* If it's not incremental, just skip over the gap, so that after
6063 jumping to retry we will output the next successive element. */
6064 if (TREE_CODE (constructor_type) == RECORD_TYPE
6065 || TREE_CODE (constructor_type) == UNION_TYPE)
6066 constructor_unfilled_fields = next;
6067 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6068 constructor_unfilled_index = next;
6070 /* ELT now points to the node in the pending tree with the next
6071 initializer to output. */
6075 /* Add one non-braced element to the current constructor level.
6076 This adjusts the current position within the constructor's type.
6077 This may also start or terminate implicit levels
6078 to handle a partly-braced initializer.
6080 Once this has found the correct level for the new element,
6081 it calls output_init_element. */
6084 process_init_element (struct c_expr value)
6086 tree orig_value = value.value;
6087 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6088 bool strict_string = value.original_code == STRING_CST;
6090 designator_depth = 0;
6091 designator_errorneous = 0;
6093 /* Handle superfluous braces around string cst as in
6094 char x[] = {"foo"}; */
6097 && TREE_CODE (constructor_type) == ARRAY_TYPE
6098 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6099 && integer_zerop (constructor_unfilled_index))
6101 if (constructor_stack->replacement_value.value)
6102 error_init ("excess elements in char array initializer");
6103 constructor_stack->replacement_value = value;
6107 if (constructor_stack->replacement_value.value != 0)
6109 error_init ("excess elements in struct initializer");
6113 /* Ignore elements of a brace group if it is entirely superfluous
6114 and has already been diagnosed. */
6115 if (constructor_type == 0)
6118 /* If we've exhausted any levels that didn't have braces,
6120 while (constructor_stack->implicit)
6122 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6123 || TREE_CODE (constructor_type) == UNION_TYPE)
6124 && constructor_fields == 0)
6125 process_init_element (pop_init_level (1));
6126 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6127 && (constructor_max_index == 0
6128 || tree_int_cst_lt (constructor_max_index,
6129 constructor_index)))
6130 process_init_element (pop_init_level (1));
6135 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6136 if (constructor_range_stack)
6138 /* If value is a compound literal and we'll be just using its
6139 content, don't put it into a SAVE_EXPR. */
6140 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6141 || !require_constant_value
6143 value.value = save_expr (value.value);
6148 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6151 enum tree_code fieldcode;
6153 if (constructor_fields == 0)
6155 pedwarn_init ("excess elements in struct initializer");
6159 fieldtype = TREE_TYPE (constructor_fields);
6160 if (fieldtype != error_mark_node)
6161 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6162 fieldcode = TREE_CODE (fieldtype);
6164 /* Error for non-static initialization of a flexible array member. */
6165 if (fieldcode == ARRAY_TYPE
6166 && !require_constant_value
6167 && TYPE_SIZE (fieldtype) == NULL_TREE
6168 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6170 error_init ("non-static initialization of a flexible array member");
6174 /* Accept a string constant to initialize a subarray. */
6175 if (value.value != 0
6176 && fieldcode == ARRAY_TYPE
6177 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6179 value.value = orig_value;
6180 /* Otherwise, if we have come to a subaggregate,
6181 and we don't have an element of its type, push into it. */
6182 else if (value.value != 0
6183 && value.value != error_mark_node
6184 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6185 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6186 || fieldcode == UNION_TYPE))
6188 push_init_level (1);
6194 push_member_name (constructor_fields);
6195 output_init_element (value.value, strict_string,
6196 fieldtype, constructor_fields, 1);
6197 RESTORE_SPELLING_DEPTH (constructor_depth);
6200 /* Do the bookkeeping for an element that was
6201 directly output as a constructor. */
6203 /* For a record, keep track of end position of last field. */
6204 if (DECL_SIZE (constructor_fields))
6205 constructor_bit_index
6206 = size_binop (PLUS_EXPR,
6207 bit_position (constructor_fields),
6208 DECL_SIZE (constructor_fields));
6210 /* If the current field was the first one not yet written out,
6211 it isn't now, so update. */
6212 if (constructor_unfilled_fields == constructor_fields)
6214 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6215 /* Skip any nameless bit fields. */
6216 while (constructor_unfilled_fields != 0
6217 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6218 && DECL_NAME (constructor_unfilled_fields) == 0)
6219 constructor_unfilled_fields =
6220 TREE_CHAIN (constructor_unfilled_fields);
6224 constructor_fields = TREE_CHAIN (constructor_fields);
6225 /* Skip any nameless bit fields at the beginning. */
6226 while (constructor_fields != 0
6227 && DECL_C_BIT_FIELD (constructor_fields)
6228 && DECL_NAME (constructor_fields) == 0)
6229 constructor_fields = TREE_CHAIN (constructor_fields);
6231 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6234 enum tree_code fieldcode;
6236 if (constructor_fields == 0)
6238 pedwarn_init ("excess elements in union initializer");
6242 fieldtype = TREE_TYPE (constructor_fields);
6243 if (fieldtype != error_mark_node)
6244 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6245 fieldcode = TREE_CODE (fieldtype);
6247 /* Warn that traditional C rejects initialization of unions.
6248 We skip the warning if the value is zero. This is done
6249 under the assumption that the zero initializer in user
6250 code appears conditioned on e.g. __STDC__ to avoid
6251 "missing initializer" warnings and relies on default
6252 initialization to zero in the traditional C case.
6253 We also skip the warning if the initializer is designated,
6254 again on the assumption that this must be conditional on
6255 __STDC__ anyway (and we've already complained about the
6256 member-designator already). */
6257 if (warn_traditional && !in_system_header && !constructor_designated
6258 && !(value.value && (integer_zerop (value.value)
6259 || real_zerop (value.value))))
6260 warning (0, "traditional C rejects initialization of unions");
6262 /* Accept a string constant to initialize a subarray. */
6263 if (value.value != 0
6264 && fieldcode == ARRAY_TYPE
6265 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6267 value.value = orig_value;
6268 /* Otherwise, if we have come to a subaggregate,
6269 and we don't have an element of its type, push into it. */
6270 else if (value.value != 0
6271 && value.value != error_mark_node
6272 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6273 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6274 || fieldcode == UNION_TYPE))
6276 push_init_level (1);
6282 push_member_name (constructor_fields);
6283 output_init_element (value.value, strict_string,
6284 fieldtype, constructor_fields, 1);
6285 RESTORE_SPELLING_DEPTH (constructor_depth);
6288 /* Do the bookkeeping for an element that was
6289 directly output as a constructor. */
6291 constructor_bit_index = DECL_SIZE (constructor_fields);
6292 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6295 constructor_fields = 0;
6297 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6299 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6300 enum tree_code eltcode = TREE_CODE (elttype);
6302 /* Accept a string constant to initialize a subarray. */
6303 if (value.value != 0
6304 && eltcode == ARRAY_TYPE
6305 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6307 value.value = orig_value;
6308 /* Otherwise, if we have come to a subaggregate,
6309 and we don't have an element of its type, push into it. */
6310 else if (value.value != 0
6311 && value.value != error_mark_node
6312 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6313 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6314 || eltcode == UNION_TYPE))
6316 push_init_level (1);
6320 if (constructor_max_index != 0
6321 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6322 || integer_all_onesp (constructor_max_index)))
6324 pedwarn_init ("excess elements in array initializer");
6328 /* Now output the actual element. */
6331 push_array_bounds (tree_low_cst (constructor_index, 0));
6332 output_init_element (value.value, strict_string,
6333 elttype, constructor_index, 1);
6334 RESTORE_SPELLING_DEPTH (constructor_depth);
6338 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6341 /* If we are doing the bookkeeping for an element that was
6342 directly output as a constructor, we must update
6343 constructor_unfilled_index. */
6344 constructor_unfilled_index = constructor_index;
6346 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6348 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6350 /* Do a basic check of initializer size. Note that vectors
6351 always have a fixed size derived from their type. */
6352 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6354 pedwarn_init ("excess elements in vector initializer");
6358 /* Now output the actual element. */
6360 output_init_element (value.value, strict_string,
6361 elttype, constructor_index, 1);
6364 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6367 /* If we are doing the bookkeeping for an element that was
6368 directly output as a constructor, we must update
6369 constructor_unfilled_index. */
6370 constructor_unfilled_index = constructor_index;
6373 /* Handle the sole element allowed in a braced initializer
6374 for a scalar variable. */
6375 else if (constructor_type != error_mark_node
6376 && constructor_fields == 0)
6378 pedwarn_init ("excess elements in scalar initializer");
6384 output_init_element (value.value, strict_string,
6385 constructor_type, NULL_TREE, 1);
6386 constructor_fields = 0;
6389 /* Handle range initializers either at this level or anywhere higher
6390 in the designator stack. */
6391 if (constructor_range_stack)
6393 struct constructor_range_stack *p, *range_stack;
6396 range_stack = constructor_range_stack;
6397 constructor_range_stack = 0;
6398 while (constructor_stack != range_stack->stack)
6400 gcc_assert (constructor_stack->implicit);
6401 process_init_element (pop_init_level (1));
6403 for (p = range_stack;
6404 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6407 gcc_assert (constructor_stack->implicit);
6408 process_init_element (pop_init_level (1));
6411 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6412 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6417 constructor_index = p->index;
6418 constructor_fields = p->fields;
6419 if (finish && p->range_end && p->index == p->range_start)
6427 push_init_level (2);
6428 p->stack = constructor_stack;
6429 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6430 p->index = p->range_start;
6434 constructor_range_stack = range_stack;
6441 constructor_range_stack = 0;
6444 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6445 (guaranteed to be 'volatile' or null) and ARGS (represented using
6446 an ASM_EXPR node). */
6448 build_asm_stmt (tree cv_qualifier, tree args)
6450 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6451 ASM_VOLATILE_P (args) = 1;
6452 return add_stmt (args);
6455 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6456 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6457 SIMPLE indicates whether there was anything at all after the
6458 string in the asm expression -- asm("blah") and asm("blah" : )
6459 are subtly different. We use a ASM_EXPR node to represent this. */
6461 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6467 const char *constraint;
6468 const char **oconstraints;
6469 bool allows_mem, allows_reg, is_inout;
6470 int ninputs, noutputs;
6472 ninputs = list_length (inputs);
6473 noutputs = list_length (outputs);
6474 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6476 string = resolve_asm_operand_names (string, outputs, inputs);
6478 /* Remove output conversions that change the type but not the mode. */
6479 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6481 tree output = TREE_VALUE (tail);
6483 /* ??? Really, this should not be here. Users should be using a
6484 proper lvalue, dammit. But there's a long history of using casts
6485 in the output operands. In cases like longlong.h, this becomes a
6486 primitive form of typechecking -- if the cast can be removed, then
6487 the output operand had a type of the proper width; otherwise we'll
6488 get an error. Gross, but ... */
6489 STRIP_NOPS (output);
6491 if (!lvalue_or_else (output, lv_asm))
6492 output = error_mark_node;
6494 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6495 oconstraints[i] = constraint;
6497 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6498 &allows_mem, &allows_reg, &is_inout))
6500 /* If the operand is going to end up in memory,
6501 mark it addressable. */
6502 if (!allows_reg && !c_mark_addressable (output))
6503 output = error_mark_node;
6506 output = error_mark_node;
6508 TREE_VALUE (tail) = output;
6511 /* Perform default conversions on array and function inputs.
6512 Don't do this for other types as it would screw up operands
6513 expected to be in memory. */
6514 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6518 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6519 input = TREE_VALUE (tail);
6521 input = default_function_array_conversion (input);
6523 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6524 oconstraints, &allows_mem, &allows_reg))
6526 /* If the operand is going to end up in memory,
6527 mark it addressable. */
6528 if (!allows_reg && allows_mem)
6530 /* Strip the nops as we allow this case. FIXME, this really
6531 should be rejected or made deprecated. */
6533 if (!c_mark_addressable (input))
6534 input = error_mark_node;
6538 input = error_mark_node;
6540 TREE_VALUE (tail) = input;
6543 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6545 /* Simple asm statements are treated as volatile. */
6548 ASM_VOLATILE_P (args) = 1;
6549 ASM_INPUT_P (args) = 1;
6555 /* Generate a goto statement to LABEL. */
6558 c_finish_goto_label (tree label)
6560 tree decl = lookup_label (label);
6564 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6566 error ("jump into statement expression");
6570 if (C_DECL_UNJUMPABLE_VM (decl))
6572 error ("jump into scope of identifier with variably modified type");
6576 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6578 /* No jump from outside this statement expression context, so
6579 record that there is a jump from within this context. */
6580 struct c_label_list *nlist;
6581 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6582 nlist->next = label_context_stack_se->labels_used;
6583 nlist->label = decl;
6584 label_context_stack_se->labels_used = nlist;
6587 if (!C_DECL_UNDEFINABLE_VM (decl))
6589 /* No jump from outside this context context of identifiers with
6590 variably modified type, so record that there is a jump from
6591 within this context. */
6592 struct c_label_list *nlist;
6593 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6594 nlist->next = label_context_stack_vm->labels_used;
6595 nlist->label = decl;
6596 label_context_stack_vm->labels_used = nlist;
6599 TREE_USED (decl) = 1;
6600 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6603 /* Generate a computed goto statement to EXPR. */
6606 c_finish_goto_ptr (tree expr)
6609 pedwarn ("ISO C forbids %<goto *expr;%>");
6610 expr = convert (ptr_type_node, expr);
6611 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6614 /* Generate a C `return' statement. RETVAL is the expression for what
6615 to return, or a null pointer for `return;' with no value. */
6618 c_finish_return (tree retval)
6620 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl));
6622 if (TREE_THIS_VOLATILE (current_function_decl))
6623 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6627 current_function_returns_null = 1;
6628 if ((warn_return_type || flag_isoc99)
6629 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6630 pedwarn_c99 ("%<return%> with no value, in "
6631 "function returning non-void");
6633 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6635 current_function_returns_null = 1;
6636 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6637 pedwarn ("%<return%> with a value, in function returning void");
6641 tree t = convert_for_assignment (valtype, retval, ic_return,
6642 NULL_TREE, NULL_TREE, 0);
6643 tree res = DECL_RESULT (current_function_decl);
6646 current_function_returns_value = 1;
6647 if (t == error_mark_node)
6650 inner = t = convert (TREE_TYPE (res), t);
6652 /* Strip any conversions, additions, and subtractions, and see if
6653 we are returning the address of a local variable. Warn if so. */
6656 switch (TREE_CODE (inner))
6658 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6660 inner = TREE_OPERAND (inner, 0);
6664 /* If the second operand of the MINUS_EXPR has a pointer
6665 type (or is converted from it), this may be valid, so
6666 don't give a warning. */
6668 tree op1 = TREE_OPERAND (inner, 1);
6670 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6671 && (TREE_CODE (op1) == NOP_EXPR
6672 || TREE_CODE (op1) == NON_LVALUE_EXPR
6673 || TREE_CODE (op1) == CONVERT_EXPR))
6674 op1 = TREE_OPERAND (op1, 0);
6676 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6679 inner = TREE_OPERAND (inner, 0);
6684 inner = TREE_OPERAND (inner, 0);
6686 while (REFERENCE_CLASS_P (inner)
6687 && TREE_CODE (inner) != INDIRECT_REF)
6688 inner = TREE_OPERAND (inner, 0);
6691 && !DECL_EXTERNAL (inner)
6692 && !TREE_STATIC (inner)
6693 && DECL_CONTEXT (inner) == current_function_decl)
6694 warning (0, "function returns address of local variable");
6704 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
6707 return add_stmt (build_stmt (RETURN_EXPR, retval));
6711 /* The SWITCH_EXPR being built. */
6714 /* The original type of the testing expression, i.e. before the
6715 default conversion is applied. */
6718 /* A splay-tree mapping the low element of a case range to the high
6719 element, or NULL_TREE if there is no high element. Used to
6720 determine whether or not a new case label duplicates an old case
6721 label. We need a tree, rather than simply a hash table, because
6722 of the GNU case range extension. */
6725 /* Number of nested statement expressions within this switch
6726 statement; if nonzero, case and default labels may not
6728 unsigned int blocked_stmt_expr;
6730 /* Scope of outermost declarations of identifiers with variably
6731 modified type within this switch statement; if nonzero, case and
6732 default labels may not appear. */
6733 unsigned int blocked_vm;
6735 /* The next node on the stack. */
6736 struct c_switch *next;
6739 /* A stack of the currently active switch statements. The innermost
6740 switch statement is on the top of the stack. There is no need to
6741 mark the stack for garbage collection because it is only active
6742 during the processing of the body of a function, and we never
6743 collect at that point. */
6745 struct c_switch *c_switch_stack;
6747 /* Start a C switch statement, testing expression EXP. Return the new
6751 c_start_case (tree exp)
6753 enum tree_code code;
6754 tree type, orig_type = error_mark_node;
6755 struct c_switch *cs;
6757 if (exp != error_mark_node)
6759 code = TREE_CODE (TREE_TYPE (exp));
6760 orig_type = TREE_TYPE (exp);
6762 if (!INTEGRAL_TYPE_P (orig_type)
6763 && code != ERROR_MARK)
6765 error ("switch quantity not an integer");
6766 exp = integer_zero_node;
6767 orig_type = error_mark_node;
6771 type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
6773 if (warn_traditional && !in_system_header
6774 && (type == long_integer_type_node
6775 || type == long_unsigned_type_node))
6776 warning (0, "%<long%> switch expression not converted to "
6777 "%<int%> in ISO C");
6779 exp = default_conversion (exp);
6780 type = TREE_TYPE (exp);
6784 /* Add this new SWITCH_EXPR to the stack. */
6785 cs = XNEW (struct c_switch);
6786 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
6787 cs->orig_type = orig_type;
6788 cs->cases = splay_tree_new (case_compare, NULL, NULL);
6789 cs->blocked_stmt_expr = 0;
6791 cs->next = c_switch_stack;
6792 c_switch_stack = cs;
6794 return add_stmt (cs->switch_expr);
6797 /* Process a case label. */
6800 do_case (tree low_value, tree high_value)
6802 tree label = NULL_TREE;
6804 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
6805 && !c_switch_stack->blocked_vm)
6807 label = c_add_case_label (c_switch_stack->cases,
6808 SWITCH_COND (c_switch_stack->switch_expr),
6809 c_switch_stack->orig_type,
6810 low_value, high_value);
6811 if (label == error_mark_node)
6814 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
6817 error ("case label in statement expression not containing "
6818 "enclosing switch statement");
6820 error ("%<default%> label in statement expression not containing "
6821 "enclosing switch statement");
6823 else if (c_switch_stack && c_switch_stack->blocked_vm)
6826 error ("case label in scope of identifier with variably modified "
6827 "type not containing enclosing switch statement");
6829 error ("%<default%> label in scope of identifier with variably "
6830 "modified type not containing enclosing switch statement");
6833 error ("case label not within a switch statement");
6835 error ("%<default%> label not within a switch statement");
6840 /* Finish the switch statement. */
6843 c_finish_case (tree body)
6845 struct c_switch *cs = c_switch_stack;
6846 location_t switch_location;
6848 SWITCH_BODY (cs->switch_expr) = body;
6850 /* We must not be within a statement expression nested in the switch
6851 at this point; we might, however, be within the scope of an
6852 identifier with variably modified type nested in the switch. */
6853 gcc_assert (!cs->blocked_stmt_expr);
6855 /* Emit warnings as needed. */
6856 if (EXPR_HAS_LOCATION (cs->switch_expr))
6857 switch_location = EXPR_LOCATION (cs->switch_expr);
6859 switch_location = input_location;
6860 c_do_switch_warnings (cs->cases, switch_location,
6861 TREE_TYPE (cs->switch_expr),
6862 SWITCH_COND (cs->switch_expr));
6864 /* Pop the stack. */
6865 c_switch_stack = cs->next;
6866 splay_tree_delete (cs->cases);
6870 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
6871 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
6872 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
6873 statement, and was not surrounded with parenthesis. */
6876 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
6877 tree else_block, bool nested_if)
6881 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
6882 if (warn_parentheses && nested_if && else_block == NULL)
6884 tree inner_if = then_block;
6886 /* We know from the grammar productions that there is an IF nested
6887 within THEN_BLOCK. Due to labels and c99 conditional declarations,
6888 it might not be exactly THEN_BLOCK, but should be the last
6889 non-container statement within. */
6891 switch (TREE_CODE (inner_if))
6896 inner_if = BIND_EXPR_BODY (inner_if);
6898 case STATEMENT_LIST:
6899 inner_if = expr_last (then_block);
6901 case TRY_FINALLY_EXPR:
6902 case TRY_CATCH_EXPR:
6903 inner_if = TREE_OPERAND (inner_if, 0);
6910 if (COND_EXPR_ELSE (inner_if))
6911 warning (0, "%Hsuggest explicit braces to avoid ambiguous %<else%>",
6915 /* Diagnose ";" via the special empty statement node that we create. */
6918 if (TREE_CODE (then_block) == NOP_EXPR && !TREE_TYPE (then_block))
6921 warning (0, "%Hempty body in an if-statement",
6922 EXPR_LOCUS (then_block));
6923 then_block = alloc_stmt_list ();
6926 && TREE_CODE (else_block) == NOP_EXPR
6927 && !TREE_TYPE (else_block))
6929 warning (0, "%Hempty body in an else-statement",
6930 EXPR_LOCUS (else_block));
6931 else_block = alloc_stmt_list ();
6935 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
6936 SET_EXPR_LOCATION (stmt, if_locus);
6940 /* Emit a general-purpose loop construct. START_LOCUS is the location of
6941 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
6942 is false for DO loops. INCR is the FOR increment expression. BODY is
6943 the statement controlled by the loop. BLAB is the break label. CLAB is
6944 the continue label. Everything is allowed to be NULL. */
6947 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
6948 tree blab, tree clab, bool cond_is_first)
6950 tree entry = NULL, exit = NULL, t;
6952 /* If the condition is zero don't generate a loop construct. */
6953 if (cond && integer_zerop (cond))
6957 t = build_and_jump (&blab);
6958 SET_EXPR_LOCATION (t, start_locus);
6964 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6966 /* If we have an exit condition, then we build an IF with gotos either
6967 out of the loop, or to the top of it. If there's no exit condition,
6968 then we just build a jump back to the top. */
6969 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
6971 if (cond && !integer_nonzerop (cond))
6973 /* Canonicalize the loop condition to the end. This means
6974 generating a branch to the loop condition. Reuse the
6975 continue label, if possible. */
6980 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
6981 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
6984 t = build1 (GOTO_EXPR, void_type_node, clab);
6985 SET_EXPR_LOCATION (t, start_locus);
6989 t = build_and_jump (&blab);
6990 exit = build3 (COND_EXPR, void_type_node, cond, exit, t);
6993 SET_EXPR_LOCATION (exit, start_locus);
6995 SET_EXPR_LOCATION (exit, input_location);
7004 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7012 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7016 c_finish_bc_stmt (tree *label_p, bool is_break)
7019 tree label = *label_p;
7021 /* In switch statements break is sometimes stylistically used after
7022 a return statement. This can lead to spurious warnings about
7023 control reaching the end of a non-void function when it is
7024 inlined. Note that we are calling block_may_fallthru with
7025 language specific tree nodes; this works because
7026 block_may_fallthru returns true when given something it does not
7028 skip = !block_may_fallthru (cur_stmt_list);
7033 *label_p = label = create_artificial_label ();
7035 else if (TREE_CODE (label) != LABEL_DECL)
7038 error ("break statement not within loop or switch");
7040 error ("continue statement not within a loop");
7047 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7050 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7053 emit_side_effect_warnings (tree expr)
7055 if (expr == error_mark_node)
7057 else if (!TREE_SIDE_EFFECTS (expr))
7059 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7060 warning (0, "%Hstatement with no effect",
7061 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7063 else if (warn_unused_value)
7064 warn_if_unused_value (expr, input_location);
7067 /* Process an expression as if it were a complete statement. Emit
7068 diagnostics, but do not call ADD_STMT. */
7071 c_process_expr_stmt (tree expr)
7076 /* Do default conversion if safe and possibly important,
7077 in case within ({...}). */
7078 if ((TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE
7079 && (flag_isoc99 || lvalue_p (expr)))
7080 || TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE)
7081 expr = default_conversion (expr);
7083 if (warn_sequence_point)
7084 verify_sequence_points (expr);
7086 if (TREE_TYPE (expr) != error_mark_node
7087 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7088 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7089 error ("expression statement has incomplete type");
7091 /* If we're not processing a statement expression, warn about unused values.
7092 Warnings for statement expressions will be emitted later, once we figure
7093 out which is the result. */
7094 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7095 && (extra_warnings || warn_unused_value))
7096 emit_side_effect_warnings (expr);
7098 /* If the expression is not of a type to which we cannot assign a line
7099 number, wrap the thing in a no-op NOP_EXPR. */
7100 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7101 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7104 SET_EXPR_LOCATION (expr, input_location);
7109 /* Emit an expression as a statement. */
7112 c_finish_expr_stmt (tree expr)
7115 return add_stmt (c_process_expr_stmt (expr));
7120 /* Do the opposite and emit a statement as an expression. To begin,
7121 create a new binding level and return it. */
7124 c_begin_stmt_expr (void)
7127 struct c_label_context_se *nstack;
7128 struct c_label_list *glist;
7130 /* We must force a BLOCK for this level so that, if it is not expanded
7131 later, there is a way to turn off the entire subtree of blocks that
7132 are contained in it. */
7134 ret = c_begin_compound_stmt (true);
7137 c_switch_stack->blocked_stmt_expr++;
7138 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7140 for (glist = label_context_stack_se->labels_used;
7142 glist = glist->next)
7144 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7146 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7147 nstack->labels_def = NULL;
7148 nstack->labels_used = NULL;
7149 nstack->next = label_context_stack_se;
7150 label_context_stack_se = nstack;
7152 /* Mark the current statement list as belonging to a statement list. */
7153 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7159 c_finish_stmt_expr (tree body)
7161 tree last, type, tmp, val;
7163 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7165 body = c_end_compound_stmt (body, true);
7168 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7169 c_switch_stack->blocked_stmt_expr--;
7171 /* It is no longer possible to jump to labels defined within this
7172 statement expression. */
7173 for (dlist = label_context_stack_se->labels_def;
7175 dlist = dlist->next)
7177 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7179 /* It is again possible to define labels with a goto just outside
7180 this statement expression. */
7181 for (glist = label_context_stack_se->next->labels_used;
7183 glist = glist->next)
7185 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7188 if (glist_prev != NULL)
7189 glist_prev->next = label_context_stack_se->labels_used;
7191 label_context_stack_se->next->labels_used
7192 = label_context_stack_se->labels_used;
7193 label_context_stack_se = label_context_stack_se->next;
7195 /* Locate the last statement in BODY. See c_end_compound_stmt
7196 about always returning a BIND_EXPR. */
7197 last_p = &BIND_EXPR_BODY (body);
7198 last = BIND_EXPR_BODY (body);
7201 if (TREE_CODE (last) == STATEMENT_LIST)
7203 tree_stmt_iterator i;
7205 /* This can happen with degenerate cases like ({ }). No value. */
7206 if (!TREE_SIDE_EFFECTS (last))
7209 /* If we're supposed to generate side effects warnings, process
7210 all of the statements except the last. */
7211 if (extra_warnings || warn_unused_value)
7213 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7214 emit_side_effect_warnings (tsi_stmt (i));
7217 i = tsi_last (last);
7218 last_p = tsi_stmt_ptr (i);
7222 /* If the end of the list is exception related, then the list was split
7223 by a call to push_cleanup. Continue searching. */
7224 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7225 || TREE_CODE (last) == TRY_CATCH_EXPR)
7227 last_p = &TREE_OPERAND (last, 0);
7229 goto continue_searching;
7232 /* In the case that the BIND_EXPR is not necessary, return the
7233 expression out from inside it. */
7234 if (last == error_mark_node
7235 || (last == BIND_EXPR_BODY (body)
7236 && BIND_EXPR_VARS (body) == NULL))
7239 /* Extract the type of said expression. */
7240 type = TREE_TYPE (last);
7242 /* If we're not returning a value at all, then the BIND_EXPR that
7243 we already have is a fine expression to return. */
7244 if (!type || VOID_TYPE_P (type))
7247 /* Now that we've located the expression containing the value, it seems
7248 silly to make voidify_wrapper_expr repeat the process. Create a
7249 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7250 tmp = create_tmp_var_raw (type, NULL);
7252 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7253 tree_expr_nonnegative_p giving up immediately. */
7255 if (TREE_CODE (val) == NOP_EXPR
7256 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7257 val = TREE_OPERAND (val, 0);
7259 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7260 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7262 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7265 /* Begin the scope of an identifier of variably modified type, scope
7266 number SCOPE. Jumping from outside this scope to inside it is not
7270 c_begin_vm_scope (unsigned int scope)
7272 struct c_label_context_vm *nstack;
7273 struct c_label_list *glist;
7275 gcc_assert (scope > 0);
7276 if (c_switch_stack && !c_switch_stack->blocked_vm)
7277 c_switch_stack->blocked_vm = scope;
7278 for (glist = label_context_stack_vm->labels_used;
7280 glist = glist->next)
7282 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7284 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7285 nstack->labels_def = NULL;
7286 nstack->labels_used = NULL;
7287 nstack->scope = scope;
7288 nstack->next = label_context_stack_vm;
7289 label_context_stack_vm = nstack;
7292 /* End a scope which may contain identifiers of variably modified
7293 type, scope number SCOPE. */
7296 c_end_vm_scope (unsigned int scope)
7298 if (label_context_stack_vm == NULL)
7300 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7301 c_switch_stack->blocked_vm = 0;
7302 /* We may have a number of nested scopes of identifiers with
7303 variably modified type, all at this depth. Pop each in turn. */
7304 while (label_context_stack_vm->scope == scope)
7306 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7308 /* It is no longer possible to jump to labels defined within this
7310 for (dlist = label_context_stack_vm->labels_def;
7312 dlist = dlist->next)
7314 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7316 /* It is again possible to define labels with a goto just outside
7318 for (glist = label_context_stack_vm->next->labels_used;
7320 glist = glist->next)
7322 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7325 if (glist_prev != NULL)
7326 glist_prev->next = label_context_stack_vm->labels_used;
7328 label_context_stack_vm->next->labels_used
7329 = label_context_stack_vm->labels_used;
7330 label_context_stack_vm = label_context_stack_vm->next;
7334 /* Begin and end compound statements. This is as simple as pushing
7335 and popping new statement lists from the tree. */
7338 c_begin_compound_stmt (bool do_scope)
7340 tree stmt = push_stmt_list ();
7347 c_end_compound_stmt (tree stmt, bool do_scope)
7353 if (c_dialect_objc ())
7354 objc_clear_super_receiver ();
7355 block = pop_scope ();
7358 stmt = pop_stmt_list (stmt);
7359 stmt = c_build_bind_expr (block, stmt);
7361 /* If this compound statement is nested immediately inside a statement
7362 expression, then force a BIND_EXPR to be created. Otherwise we'll
7363 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7364 STATEMENT_LISTs merge, and thus we can lose track of what statement
7367 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7368 && TREE_CODE (stmt) != BIND_EXPR)
7370 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7371 TREE_SIDE_EFFECTS (stmt) = 1;
7377 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7378 when the current scope is exited. EH_ONLY is true when this is not
7379 meant to apply to normal control flow transfer. */
7382 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7384 enum tree_code code;
7388 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7389 stmt = build_stmt (code, NULL, cleanup);
7391 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7392 list = push_stmt_list ();
7393 TREE_OPERAND (stmt, 0) = list;
7394 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7397 /* Build a binary-operation expression without default conversions.
7398 CODE is the kind of expression to build.
7399 This function differs from `build' in several ways:
7400 the data type of the result is computed and recorded in it,
7401 warnings are generated if arg data types are invalid,
7402 special handling for addition and subtraction of pointers is known,
7403 and some optimization is done (operations on narrow ints
7404 are done in the narrower type when that gives the same result).
7405 Constant folding is also done before the result is returned.
7407 Note that the operands will never have enumeral types, or function
7408 or array types, because either they will have the default conversions
7409 performed or they have both just been converted to some other type in which
7410 the arithmetic is to be done. */
7413 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7417 enum tree_code code0, code1;
7420 /* Expression code to give to the expression when it is built.
7421 Normally this is CODE, which is what the caller asked for,
7422 but in some special cases we change it. */
7423 enum tree_code resultcode = code;
7425 /* Data type in which the computation is to be performed.
7426 In the simplest cases this is the common type of the arguments. */
7427 tree result_type = NULL;
7429 /* Nonzero means operands have already been type-converted
7430 in whatever way is necessary.
7431 Zero means they need to be converted to RESULT_TYPE. */
7434 /* Nonzero means create the expression with this type, rather than
7436 tree build_type = 0;
7438 /* Nonzero means after finally constructing the expression
7439 convert it to this type. */
7440 tree final_type = 0;
7442 /* Nonzero if this is an operation like MIN or MAX which can
7443 safely be computed in short if both args are promoted shorts.
7444 Also implies COMMON.
7445 -1 indicates a bitwise operation; this makes a difference
7446 in the exact conditions for when it is safe to do the operation
7447 in a narrower mode. */
7450 /* Nonzero if this is a comparison operation;
7451 if both args are promoted shorts, compare the original shorts.
7452 Also implies COMMON. */
7453 int short_compare = 0;
7455 /* Nonzero if this is a right-shift operation, which can be computed on the
7456 original short and then promoted if the operand is a promoted short. */
7457 int short_shift = 0;
7459 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7462 /* True means types are compatible as far as ObjC is concerned. */
7467 op0 = default_conversion (orig_op0);
7468 op1 = default_conversion (orig_op1);
7476 type0 = TREE_TYPE (op0);
7477 type1 = TREE_TYPE (op1);
7479 /* The expression codes of the data types of the arguments tell us
7480 whether the arguments are integers, floating, pointers, etc. */
7481 code0 = TREE_CODE (type0);
7482 code1 = TREE_CODE (type1);
7484 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7485 STRIP_TYPE_NOPS (op0);
7486 STRIP_TYPE_NOPS (op1);
7488 /* If an error was already reported for one of the arguments,
7489 avoid reporting another error. */
7491 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7492 return error_mark_node;
7494 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7499 /* Handle the pointer + int case. */
7500 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7501 return pointer_int_sum (PLUS_EXPR, op0, op1);
7502 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7503 return pointer_int_sum (PLUS_EXPR, op1, op0);
7509 /* Subtraction of two similar pointers.
7510 We must subtract them as integers, then divide by object size. */
7511 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7512 && comp_target_types (type0, type1))
7513 return pointer_diff (op0, op1);
7514 /* Handle pointer minus int. Just like pointer plus int. */
7515 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7516 return pointer_int_sum (MINUS_EXPR, op0, op1);
7525 case TRUNC_DIV_EXPR:
7527 case FLOOR_DIV_EXPR:
7528 case ROUND_DIV_EXPR:
7529 case EXACT_DIV_EXPR:
7530 /* Floating point division by zero is a legitimate way to obtain
7531 infinities and NaNs. */
7532 if (skip_evaluation == 0 && integer_zerop (op1))
7533 warning (OPT_Wdiv_by_zero, "division by zero");
7535 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7536 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7537 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7538 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7540 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7541 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7542 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7543 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7545 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
7546 resultcode = RDIV_EXPR;
7548 /* Although it would be tempting to shorten always here, that
7549 loses on some targets, since the modulo instruction is
7550 undefined if the quotient can't be represented in the
7551 computation mode. We shorten only if unsigned or if
7552 dividing by something we know != -1. */
7553 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7554 || (TREE_CODE (op1) == INTEGER_CST
7555 && !integer_all_onesp (op1)));
7563 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7565 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7569 case TRUNC_MOD_EXPR:
7570 case FLOOR_MOD_EXPR:
7571 if (skip_evaluation == 0 && integer_zerop (op1))
7572 warning (OPT_Wdiv_by_zero, "division by zero");
7574 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7576 /* Although it would be tempting to shorten always here, that loses
7577 on some targets, since the modulo instruction is undefined if the
7578 quotient can't be represented in the computation mode. We shorten
7579 only if unsigned or if dividing by something we know != -1. */
7580 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7581 || (TREE_CODE (op1) == INTEGER_CST
7582 && !integer_all_onesp (op1)));
7587 case TRUTH_ANDIF_EXPR:
7588 case TRUTH_ORIF_EXPR:
7589 case TRUTH_AND_EXPR:
7591 case TRUTH_XOR_EXPR:
7592 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7593 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7594 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7595 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7597 /* Result of these operations is always an int,
7598 but that does not mean the operands should be
7599 converted to ints! */
7600 result_type = integer_type_node;
7601 op0 = c_common_truthvalue_conversion (op0);
7602 op1 = c_common_truthvalue_conversion (op1);
7607 /* Shift operations: result has same type as first operand;
7608 always convert second operand to int.
7609 Also set SHORT_SHIFT if shifting rightward. */
7612 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7614 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7616 if (tree_int_cst_sgn (op1) < 0)
7617 warning (0, "right shift count is negative");
7620 if (!integer_zerop (op1))
7623 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7624 warning (0, "right shift count >= width of type");
7628 /* Use the type of the value to be shifted. */
7629 result_type = type0;
7630 /* Convert the shift-count to an integer, regardless of size
7631 of value being shifted. */
7632 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7633 op1 = convert (integer_type_node, op1);
7634 /* Avoid converting op1 to result_type later. */
7640 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7642 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7644 if (tree_int_cst_sgn (op1) < 0)
7645 warning (0, "left shift count is negative");
7647 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7648 warning (0, "left shift count >= width of type");
7651 /* Use the type of the value to be shifted. */
7652 result_type = type0;
7653 /* Convert the shift-count to an integer, regardless of size
7654 of value being shifted. */
7655 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7656 op1 = convert (integer_type_node, op1);
7657 /* Avoid converting op1 to result_type later. */
7664 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7665 warning (OPT_Wfloat_equal,
7666 "comparing floating point with == or != is unsafe");
7667 /* Result of comparison is always int,
7668 but don't convert the args to int! */
7669 build_type = integer_type_node;
7670 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7671 || code0 == COMPLEX_TYPE)
7672 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7673 || code1 == COMPLEX_TYPE))
7675 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7677 tree tt0 = TREE_TYPE (type0);
7678 tree tt1 = TREE_TYPE (type1);
7679 /* Anything compares with void *. void * compares with anything.
7680 Otherwise, the targets must be compatible
7681 and both must be object or both incomplete. */
7682 if (comp_target_types (type0, type1))
7683 result_type = common_pointer_type (type0, type1);
7684 else if (VOID_TYPE_P (tt0))
7686 /* op0 != orig_op0 detects the case of something
7687 whose value is 0 but which isn't a valid null ptr const. */
7688 if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
7689 && TREE_CODE (tt1) == FUNCTION_TYPE)
7690 pedwarn ("ISO C forbids comparison of %<void *%>"
7691 " with function pointer");
7693 else if (VOID_TYPE_P (tt1))
7695 if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
7696 && TREE_CODE (tt0) == FUNCTION_TYPE)
7697 pedwarn ("ISO C forbids comparison of %<void *%>"
7698 " with function pointer");
7701 /* Avoid warning about the volatile ObjC EH puts on decls. */
7703 pedwarn ("comparison of distinct pointer types lacks a cast");
7705 if (result_type == NULL_TREE)
7706 result_type = ptr_type_node;
7708 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7709 && integer_zerop (op1))
7710 result_type = type0;
7711 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7712 && integer_zerop (op0))
7713 result_type = type1;
7714 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7716 result_type = type0;
7717 pedwarn ("comparison between pointer and integer");
7719 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7721 result_type = type1;
7722 pedwarn ("comparison between pointer and integer");
7730 build_type = integer_type_node;
7731 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
7732 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
7734 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7736 if (comp_target_types (type0, type1))
7738 result_type = common_pointer_type (type0, type1);
7739 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
7740 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
7741 pedwarn ("comparison of complete and incomplete pointers");
7743 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
7744 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
7748 result_type = ptr_type_node;
7749 pedwarn ("comparison of distinct pointer types lacks a cast");
7752 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
7753 && integer_zerop (op1))
7755 result_type = type0;
7756 if (pedantic || extra_warnings)
7757 pedwarn ("ordered comparison of pointer with integer zero");
7759 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
7760 && integer_zerop (op0))
7762 result_type = type1;
7764 pedwarn ("ordered comparison of pointer with integer zero");
7766 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7768 result_type = type0;
7769 pedwarn ("comparison between pointer and integer");
7771 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
7773 result_type = type1;
7774 pedwarn ("comparison between pointer and integer");
7782 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7783 return error_mark_node;
7785 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
7786 || code0 == VECTOR_TYPE)
7788 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
7789 || code1 == VECTOR_TYPE))
7791 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
7793 if (shorten || common || short_compare)
7794 result_type = c_common_type (type0, type1);
7796 /* For certain operations (which identify themselves by shorten != 0)
7797 if both args were extended from the same smaller type,
7798 do the arithmetic in that type and then extend.
7800 shorten !=0 and !=1 indicates a bitwise operation.
7801 For them, this optimization is safe only if
7802 both args are zero-extended or both are sign-extended.
7803 Otherwise, we might change the result.
7804 Eg, (short)-1 | (unsigned short)-1 is (int)-1
7805 but calculated in (unsigned short) it would be (unsigned short)-1. */
7807 if (shorten && none_complex)
7809 int unsigned0, unsigned1;
7810 tree arg0 = get_narrower (op0, &unsigned0);
7811 tree arg1 = get_narrower (op1, &unsigned1);
7812 /* UNS is 1 if the operation to be done is an unsigned one. */
7813 int uns = TYPE_UNSIGNED (result_type);
7816 final_type = result_type;
7818 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
7819 but it *requires* conversion to FINAL_TYPE. */
7821 if ((TYPE_PRECISION (TREE_TYPE (op0))
7822 == TYPE_PRECISION (TREE_TYPE (arg0)))
7823 && TREE_TYPE (op0) != final_type)
7824 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
7825 if ((TYPE_PRECISION (TREE_TYPE (op1))
7826 == TYPE_PRECISION (TREE_TYPE (arg1)))
7827 && TREE_TYPE (op1) != final_type)
7828 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
7830 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
7832 /* For bitwise operations, signedness of nominal type
7833 does not matter. Consider only how operands were extended. */
7837 /* Note that in all three cases below we refrain from optimizing
7838 an unsigned operation on sign-extended args.
7839 That would not be valid. */
7841 /* Both args variable: if both extended in same way
7842 from same width, do it in that width.
7843 Do it unsigned if args were zero-extended. */
7844 if ((TYPE_PRECISION (TREE_TYPE (arg0))
7845 < TYPE_PRECISION (result_type))
7846 && (TYPE_PRECISION (TREE_TYPE (arg1))
7847 == TYPE_PRECISION (TREE_TYPE (arg0)))
7848 && unsigned0 == unsigned1
7849 && (unsigned0 || !uns))
7851 = c_common_signed_or_unsigned_type
7852 (unsigned0, c_common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
7853 else if (TREE_CODE (arg0) == INTEGER_CST
7854 && (unsigned1 || !uns)
7855 && (TYPE_PRECISION (TREE_TYPE (arg1))
7856 < TYPE_PRECISION (result_type))
7858 = c_common_signed_or_unsigned_type (unsigned1,
7860 int_fits_type_p (arg0, type)))
7862 else if (TREE_CODE (arg1) == INTEGER_CST
7863 && (unsigned0 || !uns)
7864 && (TYPE_PRECISION (TREE_TYPE (arg0))
7865 < TYPE_PRECISION (result_type))
7867 = c_common_signed_or_unsigned_type (unsigned0,
7869 int_fits_type_p (arg1, type)))
7873 /* Shifts can be shortened if shifting right. */
7878 tree arg0 = get_narrower (op0, &unsigned_arg);
7880 final_type = result_type;
7882 if (arg0 == op0 && final_type == TREE_TYPE (op0))
7883 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
7885 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
7886 /* We can shorten only if the shift count is less than the
7887 number of bits in the smaller type size. */
7888 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
7889 /* We cannot drop an unsigned shift after sign-extension. */
7890 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
7892 /* Do an unsigned shift if the operand was zero-extended. */
7894 = c_common_signed_or_unsigned_type (unsigned_arg,
7896 /* Convert value-to-be-shifted to that type. */
7897 if (TREE_TYPE (op0) != result_type)
7898 op0 = convert (result_type, op0);
7903 /* Comparison operations are shortened too but differently.
7904 They identify themselves by setting short_compare = 1. */
7908 /* Don't write &op0, etc., because that would prevent op0
7909 from being kept in a register.
7910 Instead, make copies of the our local variables and
7911 pass the copies by reference, then copy them back afterward. */
7912 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
7913 enum tree_code xresultcode = resultcode;
7915 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
7920 op0 = xop0, op1 = xop1;
7922 resultcode = xresultcode;
7924 if (warn_sign_compare && skip_evaluation == 0)
7926 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
7927 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
7928 int unsignedp0, unsignedp1;
7929 tree primop0 = get_narrower (op0, &unsignedp0);
7930 tree primop1 = get_narrower (op1, &unsignedp1);
7934 STRIP_TYPE_NOPS (xop0);
7935 STRIP_TYPE_NOPS (xop1);
7937 /* Give warnings for comparisons between signed and unsigned
7938 quantities that may fail.
7940 Do the checking based on the original operand trees, so that
7941 casts will be considered, but default promotions won't be.
7943 Do not warn if the comparison is being done in a signed type,
7944 since the signed type will only be chosen if it can represent
7945 all the values of the unsigned type. */
7946 if (!TYPE_UNSIGNED (result_type))
7948 /* Do not warn if both operands are the same signedness. */
7949 else if (op0_signed == op1_signed)
7956 sop = xop0, uop = xop1;
7958 sop = xop1, uop = xop0;
7960 /* Do not warn if the signed quantity is an
7961 unsuffixed integer literal (or some static
7962 constant expression involving such literals or a
7963 conditional expression involving such literals)
7964 and it is non-negative. */
7965 if (tree_expr_nonnegative_p (sop))
7967 /* Do not warn if the comparison is an equality operation,
7968 the unsigned quantity is an integral constant, and it
7969 would fit in the result if the result were signed. */
7970 else if (TREE_CODE (uop) == INTEGER_CST
7971 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
7973 (uop, c_common_signed_type (result_type)))
7975 /* Do not warn if the unsigned quantity is an enumeration
7976 constant and its maximum value would fit in the result
7977 if the result were signed. */
7978 else if (TREE_CODE (uop) == INTEGER_CST
7979 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
7981 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
7982 c_common_signed_type (result_type)))
7985 warning (0, "comparison between signed and unsigned");
7988 /* Warn if two unsigned values are being compared in a size
7989 larger than their original size, and one (and only one) is the
7990 result of a `~' operator. This comparison will always fail.
7992 Also warn if one operand is a constant, and the constant
7993 does not have all bits set that are set in the ~ operand
7994 when it is extended. */
7996 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
7997 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
7999 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8000 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8003 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8006 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8009 HOST_WIDE_INT constant, mask;
8010 int unsignedp, bits;
8012 if (host_integerp (primop0, 0))
8015 unsignedp = unsignedp1;
8016 constant = tree_low_cst (primop0, 0);
8021 unsignedp = unsignedp0;
8022 constant = tree_low_cst (primop1, 0);
8025 bits = TYPE_PRECISION (TREE_TYPE (primop));
8026 if (bits < TYPE_PRECISION (result_type)
8027 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8029 mask = (~(HOST_WIDE_INT) 0) << bits;
8030 if ((mask & constant) != mask)
8031 warning (0, "comparison of promoted ~unsigned with constant");
8034 else if (unsignedp0 && unsignedp1
8035 && (TYPE_PRECISION (TREE_TYPE (primop0))
8036 < TYPE_PRECISION (result_type))
8037 && (TYPE_PRECISION (TREE_TYPE (primop1))
8038 < TYPE_PRECISION (result_type)))
8039 warning (0, "comparison of promoted ~unsigned with unsigned");
8045 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8046 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8047 Then the expression will be built.
8048 It will be given type FINAL_TYPE if that is nonzero;
8049 otherwise, it will be given type RESULT_TYPE. */
8053 binary_op_error (code);
8054 return error_mark_node;
8059 if (TREE_TYPE (op0) != result_type)
8060 op0 = convert (result_type, op0);
8061 if (TREE_TYPE (op1) != result_type)
8062 op1 = convert (result_type, op1);
8064 /* This can happen if one operand has a vector type, and the other
8065 has a different type. */
8066 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8067 return error_mark_node;
8070 if (build_type == NULL_TREE)
8071 build_type = result_type;
8074 tree result = build2 (resultcode, build_type, op0, op1);
8076 /* Treat expressions in initializers specially as they can't trap. */
8077 result = require_constant_value ? fold_initializer (result)
8080 if (final_type != 0)
8081 result = convert (final_type, result);
8087 /* Convert EXPR to be a truth-value, validating its type for this
8088 purpose. Passes EXPR to default_function_array_conversion. */
8091 c_objc_common_truthvalue_conversion (tree expr)
8093 expr = default_function_array_conversion (expr);
8094 switch (TREE_CODE (TREE_TYPE (expr)))
8097 error ("used array that cannot be converted to pointer where scalar is required");
8098 return error_mark_node;
8101 error ("used struct type value where scalar is required");
8102 return error_mark_node;
8105 error ("used union type value where scalar is required");
8106 return error_mark_node;
8112 /* ??? Should we also give an error for void and vectors rather than
8113 leaving those to give errors later? */
8114 return c_common_truthvalue_conversion (expr);