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, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
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 bool null_pointer_constant_p (const_tree);
78 static tree qualify_type (tree, tree);
79 static int tagged_types_tu_compatible_p (const_tree, const_tree);
80 static int comp_target_types (tree, tree);
81 static int function_types_compatible_p (const_tree, const_tree);
82 static int type_lists_compatible_p (const_tree, const_tree);
83 static tree decl_constant_value_for_broken_optimization (tree);
84 static tree lookup_field (tree, tree);
85 static int convert_arguments (int, tree *, 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 int spelling_length (void);
93 static char *print_spelling (char *);
94 static void warning_init (int, const char *);
95 static tree digest_init (tree, tree, bool, int);
96 static void output_init_element (tree, bool, tree, tree, int);
97 static void output_pending_init_elements (int);
98 static int set_designator (int);
99 static void push_range_stack (tree);
100 static void add_pending_init (tree, tree);
101 static void set_nonincremental_init (void);
102 static void set_nonincremental_init_from_string (tree);
103 static tree find_init_member (tree);
104 static void readonly_error (tree, enum lvalue_use);
105 static int lvalue_or_else (const_tree, enum lvalue_use);
106 static int lvalue_p (const_tree);
107 static void record_maybe_used_decl (tree);
108 static int comptypes_internal (const_tree, const_tree);
110 /* Return true if EXP is a null pointer constant, false otherwise. */
113 null_pointer_constant_p (const_tree expr)
115 /* This should really operate on c_expr structures, but they aren't
116 yet available everywhere required. */
117 tree type = TREE_TYPE (expr);
118 return (TREE_CODE (expr) == INTEGER_CST
119 && !TREE_OVERFLOW (expr)
120 && integer_zerop (expr)
121 && (INTEGRAL_TYPE_P (type)
122 || (TREE_CODE (type) == POINTER_TYPE
123 && VOID_TYPE_P (TREE_TYPE (type))
124 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
126 \f/* This is a cache to hold if two types are compatible or not. */
128 struct tagged_tu_seen_cache {
129 const struct tagged_tu_seen_cache * next;
132 /* The return value of tagged_types_tu_compatible_p if we had seen
133 these two types already. */
137 static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
138 static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
140 /* Do `exp = require_complete_type (exp);' to make sure exp
141 does not have an incomplete type. (That includes void types.) */
144 require_complete_type (tree value)
146 tree type = TREE_TYPE (value);
148 if (value == error_mark_node || type == error_mark_node)
149 return error_mark_node;
151 /* First, detect a valid value with a complete type. */
152 if (COMPLETE_TYPE_P (type))
155 c_incomplete_type_error (value, type);
156 return error_mark_node;
159 /* Print an error message for invalid use of an incomplete type.
160 VALUE is the expression that was used (or 0 if that isn't known)
161 and TYPE is the type that was invalid. */
164 c_incomplete_type_error (const_tree value, const_tree type)
166 const char *type_code_string;
168 /* Avoid duplicate error message. */
169 if (TREE_CODE (type) == ERROR_MARK)
172 if (value != 0 && (TREE_CODE (value) == VAR_DECL
173 || TREE_CODE (value) == PARM_DECL))
174 error ("%qD has an incomplete type", value);
178 /* We must print an error message. Be clever about what it says. */
180 switch (TREE_CODE (type))
183 type_code_string = "struct";
187 type_code_string = "union";
191 type_code_string = "enum";
195 error ("invalid use of void expression");
199 if (TYPE_DOMAIN (type))
201 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
203 error ("invalid use of flexible array member");
206 type = TREE_TYPE (type);
209 error ("invalid use of array with unspecified bounds");
216 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
217 error ("invalid use of undefined type %<%s %E%>",
218 type_code_string, TYPE_NAME (type));
220 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
221 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
225 /* Given a type, apply default promotions wrt unnamed function
226 arguments and return the new type. */
229 c_type_promotes_to (tree type)
231 if (TYPE_MAIN_VARIANT (type) == float_type_node)
232 return double_type_node;
234 if (c_promoting_integer_type_p (type))
236 /* Preserve unsignedness if not really getting any wider. */
237 if (TYPE_UNSIGNED (type)
238 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
239 return unsigned_type_node;
240 return integer_type_node;
246 /* Return a variant of TYPE which has all the type qualifiers of LIKE
247 as well as those of TYPE. */
250 qualify_type (tree type, tree like)
252 return c_build_qualified_type (type,
253 TYPE_QUALS (type) | TYPE_QUALS (like));
256 /* Return true iff the given tree T is a variable length array. */
259 c_vla_type_p (const_tree t)
261 if (TREE_CODE (t) == ARRAY_TYPE
262 && C_TYPE_VARIABLE_SIZE (t))
267 /* Return the composite type of two compatible types.
269 We assume that comptypes has already been done and returned
270 nonzero; if that isn't so, this may crash. In particular, we
271 assume that qualifiers match. */
274 composite_type (tree t1, tree t2)
276 enum tree_code code1;
277 enum tree_code code2;
280 /* Save time if the two types are the same. */
282 if (t1 == t2) return t1;
284 /* If one type is nonsense, use the other. */
285 if (t1 == error_mark_node)
287 if (t2 == error_mark_node)
290 code1 = TREE_CODE (t1);
291 code2 = TREE_CODE (t2);
293 /* Merge the attributes. */
294 attributes = targetm.merge_type_attributes (t1, t2);
296 /* If one is an enumerated type and the other is the compatible
297 integer type, the composite type might be either of the two
298 (DR#013 question 3). For consistency, use the enumerated type as
299 the composite type. */
301 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
303 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
306 gcc_assert (code1 == code2);
311 /* For two pointers, do this recursively on the target type. */
313 tree pointed_to_1 = TREE_TYPE (t1);
314 tree pointed_to_2 = TREE_TYPE (t2);
315 tree target = composite_type (pointed_to_1, pointed_to_2);
316 t1 = build_pointer_type (target);
317 t1 = build_type_attribute_variant (t1, attributes);
318 return qualify_type (t1, t2);
323 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
326 tree d1 = TYPE_DOMAIN (t1);
327 tree d2 = TYPE_DOMAIN (t2);
328 bool d1_variable, d2_variable;
329 bool d1_zero, d2_zero;
331 /* We should not have any type quals on arrays at all. */
332 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
334 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
335 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
337 d1_variable = (!d1_zero
338 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
339 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
340 d2_variable = (!d2_zero
341 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
342 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
343 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
344 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
346 /* Save space: see if the result is identical to one of the args. */
347 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
348 && (d2_variable || d2_zero || !d1_variable))
349 return build_type_attribute_variant (t1, attributes);
350 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
351 && (d1_variable || d1_zero || !d2_variable))
352 return build_type_attribute_variant (t2, attributes);
354 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
355 return build_type_attribute_variant (t1, attributes);
356 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
357 return build_type_attribute_variant (t2, attributes);
359 /* Merge the element types, and have a size if either arg has
360 one. We may have qualifiers on the element types. To set
361 up TYPE_MAIN_VARIANT correctly, we need to form the
362 composite of the unqualified types and add the qualifiers
364 quals = TYPE_QUALS (strip_array_types (elt));
365 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
366 t1 = build_array_type (unqual_elt,
367 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
373 t1 = c_build_qualified_type (t1, quals);
374 return build_type_attribute_variant (t1, attributes);
380 if (attributes != NULL)
382 /* Try harder not to create a new aggregate type. */
383 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
385 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
388 return build_type_attribute_variant (t1, attributes);
391 /* Function types: prefer the one that specified arg types.
392 If both do, merge the arg types. Also merge the return types. */
394 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
395 tree p1 = TYPE_ARG_TYPES (t1);
396 tree p2 = TYPE_ARG_TYPES (t2);
401 /* Save space: see if the result is identical to one of the args. */
402 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
403 return build_type_attribute_variant (t1, attributes);
404 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
405 return build_type_attribute_variant (t2, attributes);
407 /* Simple way if one arg fails to specify argument types. */
408 if (TYPE_ARG_TYPES (t1) == 0)
410 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
411 t1 = build_type_attribute_variant (t1, attributes);
412 return qualify_type (t1, t2);
414 if (TYPE_ARG_TYPES (t2) == 0)
416 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
417 t1 = build_type_attribute_variant (t1, attributes);
418 return qualify_type (t1, t2);
421 /* If both args specify argument types, we must merge the two
422 lists, argument by argument. */
423 /* Tell global_bindings_p to return false so that variable_size
424 doesn't die on VLAs in parameter types. */
425 c_override_global_bindings_to_false = true;
427 len = list_length (p1);
430 for (i = 0; i < len; i++)
431 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
436 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
438 /* A null type means arg type is not specified.
439 Take whatever the other function type has. */
440 if (TREE_VALUE (p1) == 0)
442 TREE_VALUE (n) = TREE_VALUE (p2);
445 if (TREE_VALUE (p2) == 0)
447 TREE_VALUE (n) = TREE_VALUE (p1);
451 /* Given wait (union {union wait *u; int *i} *)
452 and wait (union wait *),
453 prefer union wait * as type of parm. */
454 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
455 && TREE_VALUE (p1) != TREE_VALUE (p2))
458 tree mv2 = TREE_VALUE (p2);
459 if (mv2 && mv2 != error_mark_node
460 && TREE_CODE (mv2) != ARRAY_TYPE)
461 mv2 = TYPE_MAIN_VARIANT (mv2);
462 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
463 memb; memb = TREE_CHAIN (memb))
465 tree mv3 = TREE_TYPE (memb);
466 if (mv3 && mv3 != error_mark_node
467 && TREE_CODE (mv3) != ARRAY_TYPE)
468 mv3 = TYPE_MAIN_VARIANT (mv3);
469 if (comptypes (mv3, mv2))
471 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
474 pedwarn ("function types not truly compatible in ISO C");
479 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
480 && TREE_VALUE (p2) != TREE_VALUE (p1))
483 tree mv1 = TREE_VALUE (p1);
484 if (mv1 && mv1 != error_mark_node
485 && TREE_CODE (mv1) != ARRAY_TYPE)
486 mv1 = TYPE_MAIN_VARIANT (mv1);
487 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
488 memb; memb = TREE_CHAIN (memb))
490 tree mv3 = TREE_TYPE (memb);
491 if (mv3 && mv3 != error_mark_node
492 && TREE_CODE (mv3) != ARRAY_TYPE)
493 mv3 = TYPE_MAIN_VARIANT (mv3);
494 if (comptypes (mv3, mv1))
496 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
499 pedwarn ("function types not truly compatible in ISO C");
504 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
508 c_override_global_bindings_to_false = false;
509 t1 = build_function_type (valtype, newargs);
510 t1 = qualify_type (t1, t2);
511 /* ... falls through ... */
515 return build_type_attribute_variant (t1, attributes);
520 /* Return the type of a conditional expression between pointers to
521 possibly differently qualified versions of compatible types.
523 We assume that comp_target_types has already been done and returned
524 nonzero; if that isn't so, this may crash. */
527 common_pointer_type (tree t1, tree t2)
530 tree pointed_to_1, mv1;
531 tree pointed_to_2, mv2;
533 unsigned target_quals;
535 /* Save time if the two types are the same. */
537 if (t1 == t2) return t1;
539 /* If one type is nonsense, use the other. */
540 if (t1 == error_mark_node)
542 if (t2 == error_mark_node)
545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
546 && TREE_CODE (t2) == POINTER_TYPE);
548 /* Merge the attributes. */
549 attributes = targetm.merge_type_attributes (t1, t2);
551 /* Find the composite type of the target types, and combine the
552 qualifiers of the two types' targets. Do not lose qualifiers on
553 array element types by taking the TYPE_MAIN_VARIANT. */
554 mv1 = pointed_to_1 = TREE_TYPE (t1);
555 mv2 = pointed_to_2 = TREE_TYPE (t2);
556 if (TREE_CODE (mv1) != ARRAY_TYPE)
557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
558 if (TREE_CODE (mv2) != ARRAY_TYPE)
559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
560 target = composite_type (mv1, mv2);
562 /* For function types do not merge const qualifiers, but drop them
563 if used inconsistently. The middle-end uses these to mark const
564 and noreturn functions. */
565 if (TREE_CODE (pointed_to_1) == FUNCTION_TYPE)
566 target_quals = TYPE_QUALS (pointed_to_1) & TYPE_QUALS (pointed_to_2);
568 target_quals = TYPE_QUALS (pointed_to_1) | TYPE_QUALS (pointed_to_2);
569 t1 = build_pointer_type (c_build_qualified_type (target, target_quals));
570 return build_type_attribute_variant (t1, attributes);
573 /* Return the common type for two arithmetic types under the usual
574 arithmetic conversions. The default conversions have already been
575 applied, and enumerated types converted to their compatible integer
576 types. The resulting type is unqualified and has no attributes.
578 This is the type for the result of most arithmetic operations
579 if the operands have the given two types. */
582 c_common_type (tree t1, tree t2)
584 enum tree_code code1;
585 enum tree_code code2;
587 /* If one type is nonsense, use the other. */
588 if (t1 == error_mark_node)
590 if (t2 == error_mark_node)
593 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
594 t1 = TYPE_MAIN_VARIANT (t1);
596 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
597 t2 = TYPE_MAIN_VARIANT (t2);
599 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
600 t1 = build_type_attribute_variant (t1, NULL_TREE);
602 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
603 t2 = build_type_attribute_variant (t2, NULL_TREE);
605 /* Save time if the two types are the same. */
607 if (t1 == t2) return t1;
609 code1 = TREE_CODE (t1);
610 code2 = TREE_CODE (t2);
612 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
613 || code1 == FIXED_POINT_TYPE || code1 == REAL_TYPE
614 || code1 == INTEGER_TYPE);
615 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
616 || code2 == FIXED_POINT_TYPE || code2 == REAL_TYPE
617 || code2 == INTEGER_TYPE);
619 /* When one operand is a decimal float type, the other operand cannot be
620 a generic float type or a complex type. We also disallow vector types
622 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
623 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
625 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
627 error ("can%'t mix operands of decimal float and vector types");
628 return error_mark_node;
630 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
632 error ("can%'t mix operands of decimal float and complex types");
633 return error_mark_node;
635 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
637 error ("can%'t mix operands of decimal float and other float types");
638 return error_mark_node;
642 /* If one type is a vector type, return that type. (How the usual
643 arithmetic conversions apply to the vector types extension is not
644 precisely specified.) */
645 if (code1 == VECTOR_TYPE)
648 if (code2 == VECTOR_TYPE)
651 /* If one type is complex, form the common type of the non-complex
652 components, then make that complex. Use T1 or T2 if it is the
654 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
656 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
657 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
658 tree subtype = c_common_type (subtype1, subtype2);
660 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
662 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
665 return build_complex_type (subtype);
668 /* If only one is real, use it as the result. */
670 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
673 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
676 /* If both are real and either are decimal floating point types, use
677 the decimal floating point type with the greater precision. */
679 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
681 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
682 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
683 return dfloat128_type_node;
684 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
685 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
686 return dfloat64_type_node;
687 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
688 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
689 return dfloat32_type_node;
692 /* Deal with fixed-point types. */
693 if (code1 == FIXED_POINT_TYPE || code2 == FIXED_POINT_TYPE)
695 unsigned int unsignedp = 0, satp = 0;
696 enum machine_mode m1, m2;
697 unsigned int fbit1, ibit1, fbit2, ibit2, max_fbit, max_ibit;
702 /* If one input type is saturating, the result type is saturating. */
703 if (TYPE_SATURATING (t1) || TYPE_SATURATING (t2))
706 /* If both fixed-point types are unsigned, the result type is unsigned.
707 When mixing fixed-point and integer types, follow the sign of the
709 Otherwise, the result type is signed. */
710 if ((TYPE_UNSIGNED (t1) && TYPE_UNSIGNED (t2)
711 && code1 == FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE)
712 || (code1 == FIXED_POINT_TYPE && code2 != FIXED_POINT_TYPE
713 && TYPE_UNSIGNED (t1))
714 || (code1 != FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE
715 && TYPE_UNSIGNED (t2)))
718 /* The result type is signed. */
721 /* If the input type is unsigned, we need to convert to the
723 if (code1 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t1))
725 enum mode_class mclass = (enum mode_class) 0;
726 if (GET_MODE_CLASS (m1) == MODE_UFRACT)
728 else if (GET_MODE_CLASS (m1) == MODE_UACCUM)
732 m1 = mode_for_size (GET_MODE_PRECISION (m1), mclass, 0);
734 if (code2 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t2))
736 enum mode_class mclass = (enum mode_class) 0;
737 if (GET_MODE_CLASS (m2) == MODE_UFRACT)
739 else if (GET_MODE_CLASS (m2) == MODE_UACCUM)
743 m2 = mode_for_size (GET_MODE_PRECISION (m2), mclass, 0);
747 if (code1 == FIXED_POINT_TYPE)
749 fbit1 = GET_MODE_FBIT (m1);
750 ibit1 = GET_MODE_IBIT (m1);
755 /* Signed integers need to subtract one sign bit. */
756 ibit1 = TYPE_PRECISION (t1) - (!TYPE_UNSIGNED (t1));
759 if (code2 == FIXED_POINT_TYPE)
761 fbit2 = GET_MODE_FBIT (m2);
762 ibit2 = GET_MODE_IBIT (m2);
767 /* Signed integers need to subtract one sign bit. */
768 ibit2 = TYPE_PRECISION (t2) - (!TYPE_UNSIGNED (t2));
771 max_ibit = ibit1 >= ibit2 ? ibit1 : ibit2;
772 max_fbit = fbit1 >= fbit2 ? fbit1 : fbit2;
773 return c_common_fixed_point_type_for_size (max_ibit, max_fbit, unsignedp,
777 /* Both real or both integers; use the one with greater precision. */
779 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
781 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
784 /* Same precision. Prefer long longs to longs to ints when the
785 same precision, following the C99 rules on integer type rank
786 (which are equivalent to the C90 rules for C90 types). */
788 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
789 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
790 return long_long_unsigned_type_node;
792 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
793 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
795 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
796 return long_long_unsigned_type_node;
798 return long_long_integer_type_node;
801 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
802 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
803 return long_unsigned_type_node;
805 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
806 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
808 /* But preserve unsignedness from the other type,
809 since long cannot hold all the values of an unsigned int. */
810 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
811 return long_unsigned_type_node;
813 return long_integer_type_node;
816 /* Likewise, prefer long double to double even if same size. */
817 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
818 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
819 return long_double_type_node;
821 /* Otherwise prefer the unsigned one. */
823 if (TYPE_UNSIGNED (t1))
829 /* Wrapper around c_common_type that is used by c-common.c and other
830 front end optimizations that remove promotions. ENUMERAL_TYPEs
831 are allowed here and are converted to their compatible integer types.
832 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
833 preferably a non-Boolean type as the common type. */
835 common_type (tree t1, tree t2)
837 if (TREE_CODE (t1) == ENUMERAL_TYPE)
838 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
839 if (TREE_CODE (t2) == ENUMERAL_TYPE)
840 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
842 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
843 if (TREE_CODE (t1) == BOOLEAN_TYPE
844 && TREE_CODE (t2) == BOOLEAN_TYPE)
845 return boolean_type_node;
847 /* If either type is BOOLEAN_TYPE, then return the other. */
848 if (TREE_CODE (t1) == BOOLEAN_TYPE)
850 if (TREE_CODE (t2) == BOOLEAN_TYPE)
853 return c_common_type (t1, t2);
856 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
857 or various other operations. Return 2 if they are compatible
858 but a warning may be needed if you use them together. */
861 comptypes (tree type1, tree type2)
863 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
866 val = comptypes_internal (type1, type2);
867 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
872 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
873 or various other operations. Return 2 if they are compatible
874 but a warning may be needed if you use them together. This
875 differs from comptypes, in that we don't free the seen types. */
878 comptypes_internal (const_tree type1, const_tree type2)
880 const_tree t1 = type1;
881 const_tree t2 = type2;
884 /* Suppress errors caused by previously reported errors. */
886 if (t1 == t2 || !t1 || !t2
887 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
890 /* If either type is the internal version of sizetype, return the
892 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
893 && TYPE_ORIG_SIZE_TYPE (t1))
894 t1 = TYPE_ORIG_SIZE_TYPE (t1);
896 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
897 && TYPE_ORIG_SIZE_TYPE (t2))
898 t2 = TYPE_ORIG_SIZE_TYPE (t2);
901 /* Enumerated types are compatible with integer types, but this is
902 not transitive: two enumerated types in the same translation unit
903 are compatible with each other only if they are the same type. */
905 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
906 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
907 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
908 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
913 /* Different classes of types can't be compatible. */
915 if (TREE_CODE (t1) != TREE_CODE (t2))
918 /* Qualifiers must match. C99 6.7.3p9 */
920 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
923 /* Allow for two different type nodes which have essentially the same
924 definition. Note that we already checked for equality of the type
925 qualifiers (just above). */
927 if (TREE_CODE (t1) != ARRAY_TYPE
928 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
931 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
932 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
935 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
938 switch (TREE_CODE (t1))
941 /* Do not remove mode or aliasing information. */
942 if (TYPE_MODE (t1) != TYPE_MODE (t2)
943 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
945 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
946 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)));
950 val = function_types_compatible_p (t1, t2);
955 tree d1 = TYPE_DOMAIN (t1);
956 tree d2 = TYPE_DOMAIN (t2);
957 bool d1_variable, d2_variable;
958 bool d1_zero, d2_zero;
961 /* Target types must match incl. qualifiers. */
962 if (TREE_TYPE (t1) != TREE_TYPE (t2)
963 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))))
966 /* Sizes must match unless one is missing or variable. */
967 if (d1 == 0 || d2 == 0 || d1 == d2)
970 d1_zero = !TYPE_MAX_VALUE (d1);
971 d2_zero = !TYPE_MAX_VALUE (d2);
973 d1_variable = (!d1_zero
974 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
975 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
976 d2_variable = (!d2_zero
977 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
978 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
979 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
980 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
982 if (d1_variable || d2_variable)
984 if (d1_zero && d2_zero)
986 if (d1_zero || d2_zero
987 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
988 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
997 if (val != 1 && !same_translation_unit_p (t1, t2))
999 tree a1 = TYPE_ATTRIBUTES (t1);
1000 tree a2 = TYPE_ATTRIBUTES (t2);
1002 if (! attribute_list_contained (a1, a2)
1003 && ! attribute_list_contained (a2, a1))
1007 return tagged_types_tu_compatible_p (t1, t2);
1008 val = tagged_types_tu_compatible_p (t1, t2);
1013 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1014 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2));
1020 return attrval == 2 && val == 1 ? 2 : val;
1023 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
1024 ignoring their qualifiers. */
1027 comp_target_types (tree ttl, tree ttr)
1032 /* Do not lose qualifiers on element types of array types that are
1033 pointer targets by taking their TYPE_MAIN_VARIANT. */
1034 mvl = TREE_TYPE (ttl);
1035 mvr = TREE_TYPE (ttr);
1036 if (TREE_CODE (mvl) != ARRAY_TYPE)
1037 mvl = TYPE_MAIN_VARIANT (mvl);
1038 if (TREE_CODE (mvr) != ARRAY_TYPE)
1039 mvr = TYPE_MAIN_VARIANT (mvr);
1040 val = comptypes (mvl, mvr);
1042 if (val == 2 && pedantic)
1043 pedwarn ("types are not quite compatible");
1047 /* Subroutines of `comptypes'. */
1049 /* Determine whether two trees derive from the same translation unit.
1050 If the CONTEXT chain ends in a null, that tree's context is still
1051 being parsed, so if two trees have context chains ending in null,
1052 they're in the same translation unit. */
1054 same_translation_unit_p (const_tree t1, const_tree t2)
1056 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
1057 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
1059 case tcc_declaration:
1060 t1 = DECL_CONTEXT (t1); break;
1062 t1 = TYPE_CONTEXT (t1); break;
1063 case tcc_exceptional:
1064 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
1065 default: gcc_unreachable ();
1068 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
1069 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
1071 case tcc_declaration:
1072 t2 = DECL_CONTEXT (t2); break;
1074 t2 = TYPE_CONTEXT (t2); break;
1075 case tcc_exceptional:
1076 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
1077 default: gcc_unreachable ();
1083 /* Allocate the seen two types, assuming that they are compatible. */
1085 static struct tagged_tu_seen_cache *
1086 alloc_tagged_tu_seen_cache (const_tree t1, const_tree t2)
1088 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
1089 tu->next = tagged_tu_seen_base;
1093 tagged_tu_seen_base = tu;
1095 /* The C standard says that two structures in different translation
1096 units are compatible with each other only if the types of their
1097 fields are compatible (among other things). We assume that they
1098 are compatible until proven otherwise when building the cache.
1099 An example where this can occur is:
1104 If we are comparing this against a similar struct in another TU,
1105 and did not assume they were compatible, we end up with an infinite
1111 /* Free the seen types until we get to TU_TIL. */
1114 free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1116 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1117 while (tu != tu_til)
1119 const struct tagged_tu_seen_cache *const tu1
1120 = (const struct tagged_tu_seen_cache *) tu;
1122 free (CONST_CAST (struct tagged_tu_seen_cache *, tu1));
1124 tagged_tu_seen_base = tu_til;
1127 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1128 compatible. If the two types are not the same (which has been
1129 checked earlier), this can only happen when multiple translation
1130 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1134 tagged_types_tu_compatible_p (const_tree t1, const_tree t2)
1137 bool needs_warning = false;
1139 /* We have to verify that the tags of the types are the same. This
1140 is harder than it looks because this may be a typedef, so we have
1141 to go look at the original type. It may even be a typedef of a
1143 In the case of compiler-created builtin structs the TYPE_DECL
1144 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1145 while (TYPE_NAME (t1)
1146 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1147 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1148 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1150 while (TYPE_NAME (t2)
1151 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1152 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1153 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1155 /* C90 didn't have the requirement that the two tags be the same. */
1156 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1159 /* C90 didn't say what happened if one or both of the types were
1160 incomplete; we choose to follow C99 rules here, which is that they
1162 if (TYPE_SIZE (t1) == NULL
1163 || TYPE_SIZE (t2) == NULL)
1167 const struct tagged_tu_seen_cache * tts_i;
1168 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1169 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1173 switch (TREE_CODE (t1))
1177 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1178 /* Speed up the case where the type values are in the same order. */
1179 tree tv1 = TYPE_VALUES (t1);
1180 tree tv2 = TYPE_VALUES (t2);
1187 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1189 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1191 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1198 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1202 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1208 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1214 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1216 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1218 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1229 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1230 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1236 /* Speed up the common case where the fields are in the same order. */
1237 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1238 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1242 if (DECL_NAME (s1) != DECL_NAME (s2))
1244 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1246 if (result != 1 && !DECL_NAME (s1))
1254 needs_warning = true;
1256 if (TREE_CODE (s1) == FIELD_DECL
1257 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1258 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1266 tu->val = needs_warning ? 2 : 1;
1270 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1274 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1275 if (DECL_NAME (s1) == DECL_NAME (s2))
1279 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1281 if (result != 1 && !DECL_NAME (s1))
1289 needs_warning = true;
1291 if (TREE_CODE (s1) == FIELD_DECL
1292 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1293 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1305 tu->val = needs_warning ? 2 : 10;
1311 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1313 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1315 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1318 if (TREE_CODE (s1) != TREE_CODE (s2)
1319 || DECL_NAME (s1) != DECL_NAME (s2))
1321 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1325 needs_warning = true;
1327 if (TREE_CODE (s1) == FIELD_DECL
1328 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1329 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1335 tu->val = needs_warning ? 2 : 1;
1344 /* Return 1 if two function types F1 and F2 are compatible.
1345 If either type specifies no argument types,
1346 the other must specify a fixed number of self-promoting arg types.
1347 Otherwise, if one type specifies only the number of arguments,
1348 the other must specify that number of self-promoting arg types.
1349 Otherwise, the argument types must match. */
1352 function_types_compatible_p (const_tree f1, const_tree f2)
1355 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1360 ret1 = TREE_TYPE (f1);
1361 ret2 = TREE_TYPE (f2);
1363 /* 'volatile' qualifiers on a function's return type used to mean
1364 the function is noreturn. */
1365 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1366 pedwarn ("function return types not compatible due to %<volatile%>");
1367 if (TYPE_VOLATILE (ret1))
1368 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1369 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1370 if (TYPE_VOLATILE (ret2))
1371 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1372 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1373 val = comptypes_internal (ret1, ret2);
1377 args1 = TYPE_ARG_TYPES (f1);
1378 args2 = TYPE_ARG_TYPES (f2);
1380 /* An unspecified parmlist matches any specified parmlist
1381 whose argument types don't need default promotions. */
1385 if (!self_promoting_args_p (args2))
1387 /* If one of these types comes from a non-prototype fn definition,
1388 compare that with the other type's arglist.
1389 If they don't match, ask for a warning (but no error). */
1390 if (TYPE_ACTUAL_ARG_TYPES (f1)
1391 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1397 if (!self_promoting_args_p (args1))
1399 if (TYPE_ACTUAL_ARG_TYPES (f2)
1400 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1405 /* Both types have argument lists: compare them and propagate results. */
1406 val1 = type_lists_compatible_p (args1, args2);
1407 return val1 != 1 ? val1 : val;
1410 /* Check two lists of types for compatibility,
1411 returning 0 for incompatible, 1 for compatible,
1412 or 2 for compatible with warning. */
1415 type_lists_compatible_p (const_tree args1, const_tree args2)
1417 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1423 tree a1, mv1, a2, mv2;
1424 if (args1 == 0 && args2 == 0)
1426 /* If one list is shorter than the other,
1427 they fail to match. */
1428 if (args1 == 0 || args2 == 0)
1430 mv1 = a1 = TREE_VALUE (args1);
1431 mv2 = a2 = TREE_VALUE (args2);
1432 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1433 mv1 = TYPE_MAIN_VARIANT (mv1);
1434 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1435 mv2 = TYPE_MAIN_VARIANT (mv2);
1436 /* A null pointer instead of a type
1437 means there is supposed to be an argument
1438 but nothing is specified about what type it has.
1439 So match anything that self-promotes. */
1442 if (c_type_promotes_to (a2) != a2)
1447 if (c_type_promotes_to (a1) != a1)
1450 /* If one of the lists has an error marker, ignore this arg. */
1451 else if (TREE_CODE (a1) == ERROR_MARK
1452 || TREE_CODE (a2) == ERROR_MARK)
1454 else if (!(newval = comptypes_internal (mv1, mv2)))
1456 /* Allow wait (union {union wait *u; int *i} *)
1457 and wait (union wait *) to be compatible. */
1458 if (TREE_CODE (a1) == UNION_TYPE
1459 && (TYPE_NAME (a1) == 0
1460 || TYPE_TRANSPARENT_UNION (a1))
1461 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1462 && tree_int_cst_equal (TYPE_SIZE (a1),
1466 for (memb = TYPE_FIELDS (a1);
1467 memb; memb = TREE_CHAIN (memb))
1469 tree mv3 = TREE_TYPE (memb);
1470 if (mv3 && mv3 != error_mark_node
1471 && TREE_CODE (mv3) != ARRAY_TYPE)
1472 mv3 = TYPE_MAIN_VARIANT (mv3);
1473 if (comptypes_internal (mv3, mv2))
1479 else if (TREE_CODE (a2) == UNION_TYPE
1480 && (TYPE_NAME (a2) == 0
1481 || TYPE_TRANSPARENT_UNION (a2))
1482 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1483 && tree_int_cst_equal (TYPE_SIZE (a2),
1487 for (memb = TYPE_FIELDS (a2);
1488 memb; memb = TREE_CHAIN (memb))
1490 tree mv3 = TREE_TYPE (memb);
1491 if (mv3 && mv3 != error_mark_node
1492 && TREE_CODE (mv3) != ARRAY_TYPE)
1493 mv3 = TYPE_MAIN_VARIANT (mv3);
1494 if (comptypes_internal (mv3, mv1))
1504 /* comptypes said ok, but record if it said to warn. */
1508 args1 = TREE_CHAIN (args1);
1509 args2 = TREE_CHAIN (args2);
1513 /* Compute the size to increment a pointer by. */
1516 c_size_in_bytes (const_tree type)
1518 enum tree_code code = TREE_CODE (type);
1520 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1521 return size_one_node;
1523 if (!COMPLETE_OR_VOID_TYPE_P (type))
1525 error ("arithmetic on pointer to an incomplete type");
1526 return size_one_node;
1529 /* Convert in case a char is more than one unit. */
1530 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1531 size_int (TYPE_PRECISION (char_type_node)
1535 /* Return either DECL or its known constant value (if it has one). */
1538 decl_constant_value (tree decl)
1540 if (/* Don't change a variable array bound or initial value to a constant
1541 in a place where a variable is invalid. Note that DECL_INITIAL
1542 isn't valid for a PARM_DECL. */
1543 current_function_decl != 0
1544 && TREE_CODE (decl) != PARM_DECL
1545 && !TREE_THIS_VOLATILE (decl)
1546 && TREE_READONLY (decl)
1547 && DECL_INITIAL (decl) != 0
1548 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1549 /* This is invalid if initial value is not constant.
1550 If it has either a function call, a memory reference,
1551 or a variable, then re-evaluating it could give different results. */
1552 && TREE_CONSTANT (DECL_INITIAL (decl))
1553 /* Check for cases where this is sub-optimal, even though valid. */
1554 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1555 return DECL_INITIAL (decl);
1559 /* Return either DECL or its known constant value (if it has one), but
1560 return DECL if pedantic or DECL has mode BLKmode. This is for
1561 bug-compatibility with the old behavior of decl_constant_value
1562 (before GCC 3.0); every use of this function is a bug and it should
1563 be removed before GCC 3.1. It is not appropriate to use pedantic
1564 in a way that affects optimization, and BLKmode is probably not the
1565 right test for avoiding misoptimizations either. */
1568 decl_constant_value_for_broken_optimization (tree decl)
1572 if (pedantic || DECL_MODE (decl) == BLKmode)
1575 ret = decl_constant_value (decl);
1576 /* Avoid unwanted tree sharing between the initializer and current
1577 function's body where the tree can be modified e.g. by the
1579 if (ret != decl && TREE_STATIC (decl))
1580 ret = unshare_expr (ret);
1584 /* Convert the array expression EXP to a pointer. */
1586 array_to_pointer_conversion (tree exp)
1588 tree orig_exp = exp;
1589 tree type = TREE_TYPE (exp);
1591 tree restype = TREE_TYPE (type);
1594 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1596 STRIP_TYPE_NOPS (exp);
1598 if (TREE_NO_WARNING (orig_exp))
1599 TREE_NO_WARNING (exp) = 1;
1601 ptrtype = build_pointer_type (restype);
1603 if (TREE_CODE (exp) == INDIRECT_REF)
1604 return convert (ptrtype, TREE_OPERAND (exp, 0));
1606 if (TREE_CODE (exp) == VAR_DECL)
1608 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1609 ADDR_EXPR because it's the best way of representing what
1610 happens in C when we take the address of an array and place
1611 it in a pointer to the element type. */
1612 adr = build1 (ADDR_EXPR, ptrtype, exp);
1613 if (!c_mark_addressable (exp))
1614 return error_mark_node;
1615 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1619 /* This way is better for a COMPONENT_REF since it can
1620 simplify the offset for a component. */
1621 adr = build_unary_op (ADDR_EXPR, exp, 1);
1622 return convert (ptrtype, adr);
1625 /* Convert the function expression EXP to a pointer. */
1627 function_to_pointer_conversion (tree exp)
1629 tree orig_exp = exp;
1631 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1633 STRIP_TYPE_NOPS (exp);
1635 if (TREE_NO_WARNING (orig_exp))
1636 TREE_NO_WARNING (exp) = 1;
1638 return build_unary_op (ADDR_EXPR, exp, 0);
1641 /* Perform the default conversion of arrays and functions to pointers.
1642 Return the result of converting EXP. For any other expression, just
1643 return EXP after removing NOPs. */
1646 default_function_array_conversion (struct c_expr exp)
1648 tree orig_exp = exp.value;
1649 tree type = TREE_TYPE (exp.value);
1650 enum tree_code code = TREE_CODE (type);
1656 bool not_lvalue = false;
1657 bool lvalue_array_p;
1659 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1660 || CONVERT_EXPR_P (exp.value))
1661 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1663 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1665 exp.value = TREE_OPERAND (exp.value, 0);
1668 if (TREE_NO_WARNING (orig_exp))
1669 TREE_NO_WARNING (exp.value) = 1;
1671 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1672 if (!flag_isoc99 && !lvalue_array_p)
1674 /* Before C99, non-lvalue arrays do not decay to pointers.
1675 Normally, using such an array would be invalid; but it can
1676 be used correctly inside sizeof or as a statement expression.
1677 Thus, do not give an error here; an error will result later. */
1681 exp.value = array_to_pointer_conversion (exp.value);
1685 exp.value = function_to_pointer_conversion (exp.value);
1688 STRIP_TYPE_NOPS (exp.value);
1689 if (TREE_NO_WARNING (orig_exp))
1690 TREE_NO_WARNING (exp.value) = 1;
1698 /* EXP is an expression of integer type. Apply the integer promotions
1699 to it and return the promoted value. */
1702 perform_integral_promotions (tree exp)
1704 tree type = TREE_TYPE (exp);
1705 enum tree_code code = TREE_CODE (type);
1707 gcc_assert (INTEGRAL_TYPE_P (type));
1709 /* Normally convert enums to int,
1710 but convert wide enums to something wider. */
1711 if (code == ENUMERAL_TYPE)
1713 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1714 TYPE_PRECISION (integer_type_node)),
1715 ((TYPE_PRECISION (type)
1716 >= TYPE_PRECISION (integer_type_node))
1717 && TYPE_UNSIGNED (type)));
1719 return convert (type, exp);
1722 /* ??? This should no longer be needed now bit-fields have their
1724 if (TREE_CODE (exp) == COMPONENT_REF
1725 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1726 /* If it's thinner than an int, promote it like a
1727 c_promoting_integer_type_p, otherwise leave it alone. */
1728 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1729 TYPE_PRECISION (integer_type_node)))
1730 return convert (integer_type_node, exp);
1732 if (c_promoting_integer_type_p (type))
1734 /* Preserve unsignedness if not really getting any wider. */
1735 if (TYPE_UNSIGNED (type)
1736 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1737 return convert (unsigned_type_node, exp);
1739 return convert (integer_type_node, exp);
1746 /* Perform default promotions for C data used in expressions.
1747 Enumeral types or short or char are converted to int.
1748 In addition, manifest constants symbols are replaced by their values. */
1751 default_conversion (tree exp)
1754 tree type = TREE_TYPE (exp);
1755 enum tree_code code = TREE_CODE (type);
1757 /* Functions and arrays have been converted during parsing. */
1758 gcc_assert (code != FUNCTION_TYPE);
1759 if (code == ARRAY_TYPE)
1762 /* Constants can be used directly unless they're not loadable. */
1763 if (TREE_CODE (exp) == CONST_DECL)
1764 exp = DECL_INITIAL (exp);
1766 /* Replace a nonvolatile const static variable with its value unless
1767 it is an array, in which case we must be sure that taking the
1768 address of the array produces consistent results. */
1769 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1771 exp = decl_constant_value_for_broken_optimization (exp);
1772 type = TREE_TYPE (exp);
1775 /* Strip no-op conversions. */
1777 STRIP_TYPE_NOPS (exp);
1779 if (TREE_NO_WARNING (orig_exp))
1780 TREE_NO_WARNING (exp) = 1;
1782 if (code == VOID_TYPE)
1784 error ("void value not ignored as it ought to be");
1785 return error_mark_node;
1788 exp = require_complete_type (exp);
1789 if (exp == error_mark_node)
1790 return error_mark_node;
1792 if (INTEGRAL_TYPE_P (type))
1793 return perform_integral_promotions (exp);
1798 /* Look up COMPONENT in a structure or union DECL.
1800 If the component name is not found, returns NULL_TREE. Otherwise,
1801 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1802 stepping down the chain to the component, which is in the last
1803 TREE_VALUE of the list. Normally the list is of length one, but if
1804 the component is embedded within (nested) anonymous structures or
1805 unions, the list steps down the chain to the component. */
1808 lookup_field (tree decl, tree component)
1810 tree type = TREE_TYPE (decl);
1813 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1814 to the field elements. Use a binary search on this array to quickly
1815 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1816 will always be set for structures which have many elements. */
1818 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1821 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1823 field = TYPE_FIELDS (type);
1825 top = TYPE_LANG_SPECIFIC (type)->s->len;
1826 while (top - bot > 1)
1828 half = (top - bot + 1) >> 1;
1829 field = field_array[bot+half];
1831 if (DECL_NAME (field) == NULL_TREE)
1833 /* Step through all anon unions in linear fashion. */
1834 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1836 field = field_array[bot++];
1837 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1838 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1840 tree anon = lookup_field (field, component);
1843 return tree_cons (NULL_TREE, field, anon);
1847 /* Entire record is only anon unions. */
1851 /* Restart the binary search, with new lower bound. */
1855 if (DECL_NAME (field) == component)
1857 if (DECL_NAME (field) < component)
1863 if (DECL_NAME (field_array[bot]) == component)
1864 field = field_array[bot];
1865 else if (DECL_NAME (field) != component)
1870 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1872 if (DECL_NAME (field) == NULL_TREE
1873 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1874 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1876 tree anon = lookup_field (field, component);
1879 return tree_cons (NULL_TREE, field, anon);
1882 if (DECL_NAME (field) == component)
1886 if (field == NULL_TREE)
1890 return tree_cons (NULL_TREE, field, NULL_TREE);
1893 /* Make an expression to refer to the COMPONENT field of
1894 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1897 build_component_ref (tree datum, tree component)
1899 tree type = TREE_TYPE (datum);
1900 enum tree_code code = TREE_CODE (type);
1904 if (!objc_is_public (datum, component))
1905 return error_mark_node;
1907 /* See if there is a field or component with name COMPONENT. */
1909 if (code == RECORD_TYPE || code == UNION_TYPE)
1911 if (!COMPLETE_TYPE_P (type))
1913 c_incomplete_type_error (NULL_TREE, type);
1914 return error_mark_node;
1917 field = lookup_field (datum, component);
1921 error ("%qT has no member named %qE", type, component);
1922 return error_mark_node;
1925 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1926 This might be better solved in future the way the C++ front
1927 end does it - by giving the anonymous entities each a
1928 separate name and type, and then have build_component_ref
1929 recursively call itself. We can't do that here. */
1932 tree subdatum = TREE_VALUE (field);
1936 if (TREE_TYPE (subdatum) == error_mark_node)
1937 return error_mark_node;
1939 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
1940 quals |= TYPE_QUALS (TREE_TYPE (datum));
1941 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
1943 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
1945 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1946 TREE_READONLY (ref) = 1;
1947 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1948 TREE_THIS_VOLATILE (ref) = 1;
1950 if (TREE_DEPRECATED (subdatum))
1951 warn_deprecated_use (subdatum);
1955 field = TREE_CHAIN (field);
1961 else if (code != ERROR_MARK)
1962 error ("request for member %qE in something not a structure or union",
1965 return error_mark_node;
1968 /* Given an expression PTR for a pointer, return an expression
1969 for the value pointed to.
1970 ERRORSTRING is the name of the operator to appear in error messages. */
1973 build_indirect_ref (tree ptr, const char *errorstring)
1975 tree pointer = default_conversion (ptr);
1976 tree type = TREE_TYPE (pointer);
1978 if (TREE_CODE (type) == POINTER_TYPE)
1980 if (CONVERT_EXPR_P (pointer)
1981 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
1983 /* If a warning is issued, mark it to avoid duplicates from
1984 the backend. This only needs to be done at
1985 warn_strict_aliasing > 2. */
1986 if (warn_strict_aliasing > 2)
1987 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
1988 type, TREE_OPERAND (pointer, 0)))
1989 TREE_NO_WARNING (pointer) = 1;
1992 if (TREE_CODE (pointer) == ADDR_EXPR
1993 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1994 == TREE_TYPE (type)))
1995 return TREE_OPERAND (pointer, 0);
1998 tree t = TREE_TYPE (type);
2001 ref = build1 (INDIRECT_REF, t, pointer);
2003 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
2005 error ("dereferencing pointer to incomplete type");
2006 return error_mark_node;
2008 if (VOID_TYPE_P (t) && skip_evaluation == 0)
2009 warning (0, "dereferencing %<void *%> pointer");
2011 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2012 so that we get the proper error message if the result is used
2013 to assign to. Also, &* is supposed to be a no-op.
2014 And ANSI C seems to specify that the type of the result
2015 should be the const type. */
2016 /* A de-reference of a pointer to const is not a const. It is valid
2017 to change it via some other pointer. */
2018 TREE_READONLY (ref) = TYPE_READONLY (t);
2019 TREE_SIDE_EFFECTS (ref)
2020 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
2021 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
2025 else if (TREE_CODE (pointer) != ERROR_MARK)
2026 error ("invalid type argument of %qs (have %qT)", errorstring, type);
2027 return error_mark_node;
2030 /* This handles expressions of the form "a[i]", which denotes
2033 This is logically equivalent in C to *(a+i), but we may do it differently.
2034 If A is a variable or a member, we generate a primitive ARRAY_REF.
2035 This avoids forcing the array out of registers, and can work on
2036 arrays that are not lvalues (for example, members of structures returned
2040 build_array_ref (tree array, tree index)
2042 bool swapped = false;
2043 if (TREE_TYPE (array) == error_mark_node
2044 || TREE_TYPE (index) == error_mark_node)
2045 return error_mark_node;
2047 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
2048 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
2051 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
2052 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
2054 error ("subscripted value is neither array nor pointer");
2055 return error_mark_node;
2063 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
2065 error ("array subscript is not an integer");
2066 return error_mark_node;
2069 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
2071 error ("subscripted value is pointer to function");
2072 return error_mark_node;
2075 /* ??? Existing practice has been to warn only when the char
2076 index is syntactically the index, not for char[array]. */
2078 warn_array_subscript_with_type_char (index);
2080 /* Apply default promotions *after* noticing character types. */
2081 index = default_conversion (index);
2083 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
2085 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2089 /* An array that is indexed by a non-constant
2090 cannot be stored in a register; we must be able to do
2091 address arithmetic on its address.
2092 Likewise an array of elements of variable size. */
2093 if (TREE_CODE (index) != INTEGER_CST
2094 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2095 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
2097 if (!c_mark_addressable (array))
2098 return error_mark_node;
2100 /* An array that is indexed by a constant value which is not within
2101 the array bounds cannot be stored in a register either; because we
2102 would get a crash in store_bit_field/extract_bit_field when trying
2103 to access a non-existent part of the register. */
2104 if (TREE_CODE (index) == INTEGER_CST
2105 && TYPE_DOMAIN (TREE_TYPE (array))
2106 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2108 if (!c_mark_addressable (array))
2109 return error_mark_node;
2115 while (TREE_CODE (foo) == COMPONENT_REF)
2116 foo = TREE_OPERAND (foo, 0);
2117 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2118 pedwarn ("ISO C forbids subscripting %<register%> array");
2119 else if (!flag_isoc99 && !lvalue_p (foo))
2120 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
2123 type = TREE_TYPE (TREE_TYPE (array));
2124 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2125 /* Array ref is const/volatile if the array elements are
2126 or if the array is. */
2127 TREE_READONLY (rval)
2128 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2129 | TREE_READONLY (array));
2130 TREE_SIDE_EFFECTS (rval)
2131 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2132 | TREE_SIDE_EFFECTS (array));
2133 TREE_THIS_VOLATILE (rval)
2134 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2135 /* This was added by rms on 16 Nov 91.
2136 It fixes vol struct foo *a; a->elts[1]
2137 in an inline function.
2138 Hope it doesn't break something else. */
2139 | TREE_THIS_VOLATILE (array));
2140 return require_complete_type (fold (rval));
2144 tree ar = default_conversion (array);
2146 if (ar == error_mark_node)
2149 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2150 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2152 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
2157 /* Build an external reference to identifier ID. FUN indicates
2158 whether this will be used for a function call. LOC is the source
2159 location of the identifier. */
2161 build_external_ref (tree id, int fun, location_t loc)
2164 tree decl = lookup_name (id);
2166 /* In Objective-C, an instance variable (ivar) may be preferred to
2167 whatever lookup_name() found. */
2168 decl = objc_lookup_ivar (decl, id);
2170 if (decl && decl != error_mark_node)
2173 /* Implicit function declaration. */
2174 ref = implicitly_declare (id);
2175 else if (decl == error_mark_node)
2176 /* Don't complain about something that's already been
2177 complained about. */
2178 return error_mark_node;
2181 undeclared_variable (id, loc);
2182 return error_mark_node;
2185 if (TREE_TYPE (ref) == error_mark_node)
2186 return error_mark_node;
2188 if (TREE_DEPRECATED (ref))
2189 warn_deprecated_use (ref);
2191 /* Recursive call does not count as usage. */
2192 if (ref != current_function_decl)
2194 if (!skip_evaluation)
2195 assemble_external (ref);
2196 TREE_USED (ref) = 1;
2199 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2201 if (!in_sizeof && !in_typeof)
2202 C_DECL_USED (ref) = 1;
2203 else if (DECL_INITIAL (ref) == 0
2204 && DECL_EXTERNAL (ref)
2205 && !TREE_PUBLIC (ref))
2206 record_maybe_used_decl (ref);
2209 if (TREE_CODE (ref) == CONST_DECL)
2211 used_types_insert (TREE_TYPE (ref));
2212 ref = DECL_INITIAL (ref);
2213 TREE_CONSTANT (ref) = 1;
2215 else if (current_function_decl != 0
2216 && !DECL_FILE_SCOPE_P (current_function_decl)
2217 && (TREE_CODE (ref) == VAR_DECL
2218 || TREE_CODE (ref) == PARM_DECL
2219 || TREE_CODE (ref) == FUNCTION_DECL))
2221 tree context = decl_function_context (ref);
2223 if (context != 0 && context != current_function_decl)
2224 DECL_NONLOCAL (ref) = 1;
2226 /* C99 6.7.4p3: An inline definition of a function with external
2227 linkage ... shall not contain a reference to an identifier with
2228 internal linkage. */
2229 else if (current_function_decl != 0
2230 && DECL_DECLARED_INLINE_P (current_function_decl)
2231 && DECL_EXTERNAL (current_function_decl)
2232 && VAR_OR_FUNCTION_DECL_P (ref)
2233 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2234 && ! TREE_PUBLIC (ref)
2235 && DECL_CONTEXT (ref) != current_function_decl)
2236 pedwarn ("%H%qD is static but used in inline function %qD "
2237 "which is not static", &loc, ref, current_function_decl);
2242 /* Record details of decls possibly used inside sizeof or typeof. */
2243 struct maybe_used_decl
2247 /* The level seen at (in_sizeof + in_typeof). */
2249 /* The next one at this level or above, or NULL. */
2250 struct maybe_used_decl *next;
2253 static struct maybe_used_decl *maybe_used_decls;
2255 /* Record that DECL, an undefined static function reference seen
2256 inside sizeof or typeof, might be used if the operand of sizeof is
2257 a VLA type or the operand of typeof is a variably modified
2261 record_maybe_used_decl (tree decl)
2263 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2265 t->level = in_sizeof + in_typeof;
2266 t->next = maybe_used_decls;
2267 maybe_used_decls = t;
2270 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2271 USED is false, just discard them. If it is true, mark them used
2272 (if no longer inside sizeof or typeof) or move them to the next
2273 level up (if still inside sizeof or typeof). */
2276 pop_maybe_used (bool used)
2278 struct maybe_used_decl *p = maybe_used_decls;
2279 int cur_level = in_sizeof + in_typeof;
2280 while (p && p->level > cur_level)
2285 C_DECL_USED (p->decl) = 1;
2287 p->level = cur_level;
2291 if (!used || cur_level == 0)
2292 maybe_used_decls = p;
2295 /* Return the result of sizeof applied to EXPR. */
2298 c_expr_sizeof_expr (struct c_expr expr)
2301 if (expr.value == error_mark_node)
2303 ret.value = error_mark_node;
2304 ret.original_code = ERROR_MARK;
2305 pop_maybe_used (false);
2309 ret.value = c_sizeof (TREE_TYPE (expr.value));
2310 ret.original_code = ERROR_MARK;
2311 if (c_vla_type_p (TREE_TYPE (expr.value)))
2313 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2314 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value);
2316 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
2321 /* Return the result of sizeof applied to T, a structure for the type
2322 name passed to sizeof (rather than the type itself). */
2325 c_expr_sizeof_type (struct c_type_name *t)
2329 type = groktypename (t);
2330 ret.value = c_sizeof (type);
2331 ret.original_code = ERROR_MARK;
2332 pop_maybe_used (type != error_mark_node
2333 ? C_TYPE_VARIABLE_SIZE (type) : false);
2337 /* Build a function call to function FUNCTION with parameters PARAMS.
2338 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2339 TREE_VALUE of each node is a parameter-expression.
2340 FUNCTION's data type may be a function type or a pointer-to-function. */
2343 build_function_call (tree function, tree params)
2345 tree fntype, fundecl = 0;
2346 tree name = NULL_TREE, result;
2352 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2353 STRIP_TYPE_NOPS (function);
2355 /* Convert anything with function type to a pointer-to-function. */
2356 if (TREE_CODE (function) == FUNCTION_DECL)
2358 /* Implement type-directed function overloading for builtins.
2359 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2360 handle all the type checking. The result is a complete expression
2361 that implements this function call. */
2362 tem = resolve_overloaded_builtin (function, params);
2366 name = DECL_NAME (function);
2369 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2370 function = function_to_pointer_conversion (function);
2372 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2373 expressions, like those used for ObjC messenger dispatches. */
2374 function = objc_rewrite_function_call (function, params);
2376 fntype = TREE_TYPE (function);
2378 if (TREE_CODE (fntype) == ERROR_MARK)
2379 return error_mark_node;
2381 if (!(TREE_CODE (fntype) == POINTER_TYPE
2382 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2384 error ("called object %qE is not a function", function);
2385 return error_mark_node;
2388 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2389 current_function_returns_abnormally = 1;
2391 /* fntype now gets the type of function pointed to. */
2392 fntype = TREE_TYPE (fntype);
2394 /* Check that the function is called through a compatible prototype.
2395 If it is not, replace the call by a trap, wrapped up in a compound
2396 expression if necessary. This has the nice side-effect to prevent
2397 the tree-inliner from generating invalid assignment trees which may
2398 blow up in the RTL expander later. */
2399 if (CONVERT_EXPR_P (function)
2400 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2401 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2402 && !comptypes (fntype, TREE_TYPE (tem)))
2404 tree return_type = TREE_TYPE (fntype);
2405 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2408 /* This situation leads to run-time undefined behavior. We can't,
2409 therefore, simply error unless we can prove that all possible
2410 executions of the program must execute the code. */
2411 warning (0, "function called through a non-compatible type");
2413 /* We can, however, treat "undefined" any way we please.
2414 Call abort to encourage the user to fix the program. */
2415 inform ("if this code is reached, the program will abort");
2417 if (VOID_TYPE_P (return_type))
2423 if (AGGREGATE_TYPE_P (return_type))
2424 rhs = build_compound_literal (return_type,
2425 build_constructor (return_type, 0));
2427 rhs = fold_convert (return_type, integer_zero_node);
2429 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2433 /* Convert the parameters to the types declared in the
2434 function prototype, or apply default promotions. */
2436 nargs = list_length (params);
2437 argarray = (tree *) alloca (nargs * sizeof (tree));
2438 nargs = convert_arguments (nargs, argarray, TYPE_ARG_TYPES (fntype),
2439 params, function, fundecl);
2441 return error_mark_node;
2443 /* Check that arguments to builtin functions match the expectations. */
2445 && DECL_BUILT_IN (fundecl)
2446 && DECL_BUILT_IN_CLASS (fundecl) == BUILT_IN_NORMAL
2447 && !check_builtin_function_arguments (fundecl, nargs, argarray))
2448 return error_mark_node;
2450 /* Check that the arguments to the function are valid. */
2451 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2452 TYPE_ARG_TYPES (fntype));
2454 if (require_constant_value)
2456 result = fold_build_call_array_initializer (TREE_TYPE (fntype),
2457 function, nargs, argarray);
2458 if (TREE_CONSTANT (result)
2459 && (name == NULL_TREE
2460 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2461 pedwarn_init ("initializer element is not constant");
2464 result = fold_build_call_array (TREE_TYPE (fntype),
2465 function, nargs, argarray);
2467 if (VOID_TYPE_P (TREE_TYPE (result)))
2469 return require_complete_type (result);
2472 /* Convert the argument expressions in the list VALUES
2473 to the types in the list TYPELIST. The resulting arguments are
2474 stored in the array ARGARRAY which has size NARGS.
2476 If TYPELIST is exhausted, or when an element has NULL as its type,
2477 perform the default conversions.
2479 PARMLIST is the chain of parm decls for the function being called.
2480 It may be 0, if that info is not available.
2481 It is used only for generating error messages.
2483 FUNCTION is a tree for the called function. It is used only for
2484 error messages, where it is formatted with %qE.
2486 This is also where warnings about wrong number of args are generated.
2488 VALUES is a chain of TREE_LIST nodes with the elements of the list
2489 in the TREE_VALUE slots of those nodes.
2491 Returns the actual number of arguments processed (which may be less
2492 than NARGS in some error situations), or -1 on failure. */
2495 convert_arguments (int nargs, tree *argarray,
2496 tree typelist, tree values, tree function, tree fundecl)
2498 tree typetail, valtail;
2500 const bool type_generic = fundecl
2501 && lookup_attribute ("type generic", TYPE_ATTRIBUTES(TREE_TYPE (fundecl)));
2504 /* Change pointer to function to the function itself for
2506 if (TREE_CODE (function) == ADDR_EXPR
2507 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2508 function = TREE_OPERAND (function, 0);
2510 /* Handle an ObjC selector specially for diagnostics. */
2511 selector = objc_message_selector ();
2513 /* Scan the given expressions and types, producing individual
2514 converted arguments and storing them in ARGARRAY. */
2516 for (valtail = values, typetail = typelist, parmnum = 0;
2518 valtail = TREE_CHAIN (valtail), parmnum++)
2520 tree type = typetail ? TREE_VALUE (typetail) : 0;
2521 tree val = TREE_VALUE (valtail);
2522 tree rname = function;
2523 int argnum = parmnum + 1;
2524 const char *invalid_func_diag;
2526 if (type == void_type_node)
2528 error ("too many arguments to function %qE", function);
2532 if (selector && argnum > 2)
2538 STRIP_TYPE_NOPS (val);
2540 val = require_complete_type (val);
2544 /* Formal parm type is specified by a function prototype. */
2547 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2549 error ("type of formal parameter %d is incomplete", parmnum + 1);
2554 /* Optionally warn about conversions that
2555 differ from the default conversions. */
2556 if (warn_traditional_conversion || warn_traditional)
2558 unsigned int formal_prec = TYPE_PRECISION (type);
2560 if (INTEGRAL_TYPE_P (type)
2561 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2562 warning (0, "passing argument %d of %qE as integer "
2563 "rather than floating due to prototype",
2565 if (INTEGRAL_TYPE_P (type)
2566 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2567 warning (0, "passing argument %d of %qE as integer "
2568 "rather than complex due to prototype",
2570 else if (TREE_CODE (type) == COMPLEX_TYPE
2571 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2572 warning (0, "passing argument %d of %qE as complex "
2573 "rather than floating due to prototype",
2575 else if (TREE_CODE (type) == REAL_TYPE
2576 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2577 warning (0, "passing argument %d of %qE as floating "
2578 "rather than integer due to prototype",
2580 else if (TREE_CODE (type) == COMPLEX_TYPE
2581 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2582 warning (0, "passing argument %d of %qE as complex "
2583 "rather than integer due to prototype",
2585 else if (TREE_CODE (type) == REAL_TYPE
2586 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2587 warning (0, "passing argument %d of %qE as floating "
2588 "rather than complex due to prototype",
2590 /* ??? At some point, messages should be written about
2591 conversions between complex types, but that's too messy
2593 else if (TREE_CODE (type) == REAL_TYPE
2594 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2596 /* Warn if any argument is passed as `float',
2597 since without a prototype it would be `double'. */
2598 if (formal_prec == TYPE_PRECISION (float_type_node)
2599 && type != dfloat32_type_node)
2600 warning (0, "passing argument %d of %qE as %<float%> "
2601 "rather than %<double%> due to prototype",
2604 /* Warn if mismatch between argument and prototype
2605 for decimal float types. Warn of conversions with
2606 binary float types and of precision narrowing due to
2608 else if (type != TREE_TYPE (val)
2609 && (type == dfloat32_type_node
2610 || type == dfloat64_type_node
2611 || type == dfloat128_type_node
2612 || TREE_TYPE (val) == dfloat32_type_node
2613 || TREE_TYPE (val) == dfloat64_type_node
2614 || TREE_TYPE (val) == dfloat128_type_node)
2616 <= TYPE_PRECISION (TREE_TYPE (val))
2617 || (type == dfloat128_type_node
2619 != dfloat64_type_node
2621 != dfloat32_type_node)))
2622 || (type == dfloat64_type_node
2624 != dfloat32_type_node))))
2625 warning (0, "passing argument %d of %qE as %qT "
2626 "rather than %qT due to prototype",
2627 argnum, rname, type, TREE_TYPE (val));
2630 /* Detect integer changing in width or signedness.
2631 These warnings are only activated with
2632 -Wtraditional-conversion, not with -Wtraditional. */
2633 else if (warn_traditional_conversion && INTEGRAL_TYPE_P (type)
2634 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2636 tree would_have_been = default_conversion (val);
2637 tree type1 = TREE_TYPE (would_have_been);
2639 if (TREE_CODE (type) == ENUMERAL_TYPE
2640 && (TYPE_MAIN_VARIANT (type)
2641 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2642 /* No warning if function asks for enum
2643 and the actual arg is that enum type. */
2645 else if (formal_prec != TYPE_PRECISION (type1))
2646 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2647 "with different width due to prototype",
2649 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2651 /* Don't complain if the formal parameter type
2652 is an enum, because we can't tell now whether
2653 the value was an enum--even the same enum. */
2654 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2656 else if (TREE_CODE (val) == INTEGER_CST
2657 && int_fits_type_p (val, type))
2658 /* Change in signedness doesn't matter
2659 if a constant value is unaffected. */
2661 /* If the value is extended from a narrower
2662 unsigned type, it doesn't matter whether we
2663 pass it as signed or unsigned; the value
2664 certainly is the same either way. */
2665 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2666 && TYPE_UNSIGNED (TREE_TYPE (val)))
2668 else if (TYPE_UNSIGNED (type))
2669 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2670 "as unsigned due to prototype",
2673 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2674 "as signed due to prototype", argnum, rname);
2678 parmval = convert_for_assignment (type, val, ic_argpass,
2682 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2683 && INTEGRAL_TYPE_P (type)
2684 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2685 parmval = default_conversion (parmval);
2687 argarray[parmnum] = parmval;
2689 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2690 && (TYPE_PRECISION (TREE_TYPE (val))
2691 < TYPE_PRECISION (double_type_node))
2692 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val))))
2695 argarray[parmnum] = val;
2697 /* Convert `float' to `double'. */
2698 argarray[parmnum] = convert (double_type_node, val);
2700 else if ((invalid_func_diag =
2701 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2703 error (invalid_func_diag);
2707 /* Convert `short' and `char' to full-size `int'. */
2708 argarray[parmnum] = default_conversion (val);
2711 typetail = TREE_CHAIN (typetail);
2714 gcc_assert (parmnum == nargs);
2716 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2718 error ("too few arguments to function %qE", function);
2725 /* This is the entry point used by the parser to build unary operators
2726 in the input. CODE, a tree_code, specifies the unary operator, and
2727 ARG is the operand. For unary plus, the C parser currently uses
2728 CONVERT_EXPR for code. */
2731 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2733 struct c_expr result;
2735 result.original_code = ERROR_MARK;
2736 result.value = build_unary_op (code, arg.value, 0);
2738 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
2739 overflow_warning (result.value);
2744 /* This is the entry point used by the parser to build binary operators
2745 in the input. CODE, a tree_code, specifies the binary operator, and
2746 ARG1 and ARG2 are the operands. In addition to constructing the
2747 expression, we check for operands that were written with other binary
2748 operators in a way that is likely to confuse the user. */
2751 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2754 struct c_expr result;
2756 enum tree_code code1 = arg1.original_code;
2757 enum tree_code code2 = arg2.original_code;
2759 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2760 result.original_code = code;
2762 if (TREE_CODE (result.value) == ERROR_MARK)
2765 /* Check for cases such as x+y<<z which users are likely
2767 if (warn_parentheses)
2768 warn_about_parentheses (code, code1, code2);
2770 if (TREE_CODE_CLASS (code1) != tcc_comparison)
2771 warn_logical_operator (code, arg1.value, arg2.value);
2773 /* Warn about comparisons against string literals, with the exception
2774 of testing for equality or inequality of a string literal with NULL. */
2775 if (code == EQ_EXPR || code == NE_EXPR)
2777 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2778 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2779 warning (OPT_Waddress, "comparison with string literal results in unspecified behavior");
2781 else if (TREE_CODE_CLASS (code) == tcc_comparison
2782 && (code1 == STRING_CST || code2 == STRING_CST))
2783 warning (OPT_Waddress, "comparison with string literal results in unspecified behavior");
2785 if (TREE_OVERFLOW_P (result.value)
2786 && !TREE_OVERFLOW_P (arg1.value)
2787 && !TREE_OVERFLOW_P (arg2.value))
2788 overflow_warning (result.value);
2793 /* Return a tree for the difference of pointers OP0 and OP1.
2794 The resulting tree has type int. */
2797 pointer_diff (tree op0, tree op1)
2799 tree restype = ptrdiff_type_node;
2801 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2802 tree con0, con1, lit0, lit1;
2803 tree orig_op1 = op1;
2805 if (pedantic || warn_pointer_arith)
2807 if (TREE_CODE (target_type) == VOID_TYPE)
2808 pedwarn ("pointer of type %<void *%> used in subtraction");
2809 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2810 pedwarn ("pointer to a function used in subtraction");
2813 /* If the conversion to ptrdiff_type does anything like widening or
2814 converting a partial to an integral mode, we get a convert_expression
2815 that is in the way to do any simplifications.
2816 (fold-const.c doesn't know that the extra bits won't be needed.
2817 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2818 different mode in place.)
2819 So first try to find a common term here 'by hand'; we want to cover
2820 at least the cases that occur in legal static initializers. */
2821 if (CONVERT_EXPR_P (op0)
2822 && (TYPE_PRECISION (TREE_TYPE (op0))
2823 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2824 con0 = TREE_OPERAND (op0, 0);
2827 if (CONVERT_EXPR_P (op1)
2828 && (TYPE_PRECISION (TREE_TYPE (op1))
2829 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2830 con1 = TREE_OPERAND (op1, 0);
2834 if (TREE_CODE (con0) == PLUS_EXPR)
2836 lit0 = TREE_OPERAND (con0, 1);
2837 con0 = TREE_OPERAND (con0, 0);
2840 lit0 = integer_zero_node;
2842 if (TREE_CODE (con1) == PLUS_EXPR)
2844 lit1 = TREE_OPERAND (con1, 1);
2845 con1 = TREE_OPERAND (con1, 0);
2848 lit1 = integer_zero_node;
2850 if (operand_equal_p (con0, con1, 0))
2857 /* First do the subtraction as integers;
2858 then drop through to build the divide operator.
2859 Do not do default conversions on the minus operator
2860 in case restype is a short type. */
2862 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2863 convert (restype, op1), 0);
2864 /* This generates an error if op1 is pointer to incomplete type. */
2865 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2866 error ("arithmetic on pointer to an incomplete type");
2868 /* This generates an error if op0 is pointer to incomplete type. */
2869 op1 = c_size_in_bytes (target_type);
2871 /* Divide by the size, in easiest possible way. */
2872 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2875 /* Construct and perhaps optimize a tree representation
2876 for a unary operation. CODE, a tree_code, specifies the operation
2877 and XARG is the operand.
2878 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2879 the default promotions (such as from short to int).
2880 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2881 allows non-lvalues; this is only used to handle conversion of non-lvalue
2882 arrays to pointers in C99. */
2885 build_unary_op (enum tree_code code, tree xarg, int flag)
2887 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2890 enum tree_code typecode;
2892 int noconvert = flag;
2893 const char *invalid_op_diag;
2895 if (code != ADDR_EXPR)
2896 arg = require_complete_type (arg);
2898 typecode = TREE_CODE (TREE_TYPE (arg));
2899 if (typecode == ERROR_MARK)
2900 return error_mark_node;
2901 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2902 typecode = INTEGER_TYPE;
2904 if ((invalid_op_diag
2905 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2907 error (invalid_op_diag);
2908 return error_mark_node;
2914 /* This is used for unary plus, because a CONVERT_EXPR
2915 is enough to prevent anybody from looking inside for
2916 associativity, but won't generate any code. */
2917 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2918 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
2919 || typecode == VECTOR_TYPE))
2921 error ("wrong type argument to unary plus");
2922 return error_mark_node;
2924 else if (!noconvert)
2925 arg = default_conversion (arg);
2926 arg = non_lvalue (arg);
2930 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2931 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
2932 || typecode == VECTOR_TYPE))
2934 error ("wrong type argument to unary minus");
2935 return error_mark_node;
2937 else if (!noconvert)
2938 arg = default_conversion (arg);
2942 /* ~ works on integer types and non float vectors. */
2943 if (typecode == INTEGER_TYPE
2944 || (typecode == VECTOR_TYPE
2945 && !VECTOR_FLOAT_TYPE_P (TREE_TYPE (arg))))
2948 arg = default_conversion (arg);
2950 else if (typecode == COMPLEX_TYPE)
2954 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2956 arg = default_conversion (arg);
2960 error ("wrong type argument to bit-complement");
2961 return error_mark_node;
2966 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2968 error ("wrong type argument to abs");
2969 return error_mark_node;
2971 else if (!noconvert)
2972 arg = default_conversion (arg);
2976 /* Conjugating a real value is a no-op, but allow it anyway. */
2977 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2978 || typecode == COMPLEX_TYPE))
2980 error ("wrong type argument to conjugation");
2981 return error_mark_node;
2983 else if (!noconvert)
2984 arg = default_conversion (arg);
2987 case TRUTH_NOT_EXPR:
2988 if (typecode != INTEGER_TYPE && typecode != FIXED_POINT_TYPE
2989 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2990 && typecode != COMPLEX_TYPE)
2992 error ("wrong type argument to unary exclamation mark");
2993 return error_mark_node;
2995 arg = c_objc_common_truthvalue_conversion (arg);
2996 return invert_truthvalue (arg);
2999 if (TREE_CODE (arg) == COMPLEX_CST)
3000 return TREE_REALPART (arg);
3001 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3002 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3007 if (TREE_CODE (arg) == COMPLEX_CST)
3008 return TREE_IMAGPART (arg);
3009 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3010 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3012 return convert (TREE_TYPE (arg), integer_zero_node);
3014 case PREINCREMENT_EXPR:
3015 case POSTINCREMENT_EXPR:
3016 case PREDECREMENT_EXPR:
3017 case POSTDECREMENT_EXPR:
3019 /* Increment or decrement the real part of the value,
3020 and don't change the imaginary part. */
3021 if (typecode == COMPLEX_TYPE)
3026 pedwarn ("ISO C does not support %<++%> and %<--%>"
3027 " on complex types");
3029 arg = stabilize_reference (arg);
3030 real = build_unary_op (REALPART_EXPR, arg, 1);
3031 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3032 real = build_unary_op (code, real, 1);
3033 if (real == error_mark_node || imag == error_mark_node)
3034 return error_mark_node;
3035 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3039 /* Report invalid types. */
3041 if (typecode != POINTER_TYPE && typecode != FIXED_POINT_TYPE
3042 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
3044 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3045 error ("wrong type argument to increment");
3047 error ("wrong type argument to decrement");
3049 return error_mark_node;
3054 tree result_type = TREE_TYPE (arg);
3056 arg = get_unwidened (arg, 0);
3057 argtype = TREE_TYPE (arg);
3059 /* Compute the increment. */
3061 if (typecode == POINTER_TYPE)
3063 /* If pointer target is an undefined struct,
3064 we just cannot know how to do the arithmetic. */
3065 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
3067 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3068 error ("increment of pointer to unknown structure");
3070 error ("decrement of pointer to unknown structure");
3072 else if ((pedantic || warn_pointer_arith)
3073 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
3074 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
3076 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3077 pedwarn ("wrong type argument to increment");
3079 pedwarn ("wrong type argument to decrement");
3082 inc = c_size_in_bytes (TREE_TYPE (result_type));
3083 inc = fold_convert (sizetype, inc);
3085 else if (FRACT_MODE_P (TYPE_MODE (result_type)))
3087 /* For signed fract types, we invert ++ to -- or
3088 -- to ++, and change inc from 1 to -1, because
3089 it is not possible to represent 1 in signed fract constants.
3090 For unsigned fract types, the result always overflows and
3091 we get an undefined (original) or the maximum value. */
3092 if (code == PREINCREMENT_EXPR)
3093 code = PREDECREMENT_EXPR;
3094 else if (code == PREDECREMENT_EXPR)
3095 code = PREINCREMENT_EXPR;
3096 else if (code == POSTINCREMENT_EXPR)
3097 code = POSTDECREMENT_EXPR;
3098 else /* code == POSTDECREMENT_EXPR */
3099 code = POSTINCREMENT_EXPR;
3101 inc = integer_minus_one_node;
3102 inc = convert (argtype, inc);
3106 inc = integer_one_node;
3107 inc = convert (argtype, inc);
3110 /* Complain about anything else that is not a true lvalue. */
3111 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3112 || code == POSTINCREMENT_EXPR)
3115 return error_mark_node;
3117 /* Report a read-only lvalue. */
3118 if (TREE_READONLY (arg))
3120 readonly_error (arg,
3121 ((code == PREINCREMENT_EXPR
3122 || code == POSTINCREMENT_EXPR)
3123 ? lv_increment : lv_decrement));
3124 return error_mark_node;
3127 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3128 val = boolean_increment (code, arg);
3130 val = build2 (code, TREE_TYPE (arg), arg, inc);
3131 TREE_SIDE_EFFECTS (val) = 1;
3132 val = convert (result_type, val);
3133 if (TREE_CODE (val) != code)
3134 TREE_NO_WARNING (val) = 1;
3139 /* Note that this operation never does default_conversion. */
3141 /* Let &* cancel out to simplify resulting code. */
3142 if (TREE_CODE (arg) == INDIRECT_REF)
3144 /* Don't let this be an lvalue. */
3145 if (lvalue_p (TREE_OPERAND (arg, 0)))
3146 return non_lvalue (TREE_OPERAND (arg, 0));
3147 return TREE_OPERAND (arg, 0);
3150 /* For &x[y], return x+y */
3151 if (TREE_CODE (arg) == ARRAY_REF)
3153 tree op0 = TREE_OPERAND (arg, 0);
3154 if (!c_mark_addressable (op0))
3155 return error_mark_node;
3156 return build_binary_op (PLUS_EXPR,
3157 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3158 ? array_to_pointer_conversion (op0)
3160 TREE_OPERAND (arg, 1), 1);
3163 /* Anything not already handled and not a true memory reference
3164 or a non-lvalue array is an error. */
3165 else if (typecode != FUNCTION_TYPE && !flag
3166 && !lvalue_or_else (arg, lv_addressof))
3167 return error_mark_node;
3169 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3170 argtype = TREE_TYPE (arg);
3172 /* If the lvalue is const or volatile, merge that into the type
3173 to which the address will point. Note that you can't get a
3174 restricted pointer by taking the address of something, so we
3175 only have to deal with `const' and `volatile' here. */
3176 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3177 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3178 argtype = c_build_type_variant (argtype,
3179 TREE_READONLY (arg),
3180 TREE_THIS_VOLATILE (arg));
3182 if (!c_mark_addressable (arg))
3183 return error_mark_node;
3185 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3186 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3188 argtype = build_pointer_type (argtype);
3190 /* ??? Cope with user tricks that amount to offsetof. Delete this
3191 when we have proper support for integer constant expressions. */
3192 val = get_base_address (arg);
3193 if (val && TREE_CODE (val) == INDIRECT_REF
3194 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3196 tree op0 = fold_convert (sizetype, fold_offsetof (arg, val)), op1;
3198 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3199 return fold_build2 (POINTER_PLUS_EXPR, argtype, op1, op0);
3202 val = build1 (ADDR_EXPR, argtype, arg);
3211 argtype = TREE_TYPE (arg);
3212 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3213 : fold_build1 (code, argtype, arg);
3216 /* Return nonzero if REF is an lvalue valid for this language.
3217 Lvalues can be assigned, unless their type has TYPE_READONLY.
3218 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3221 lvalue_p (const_tree ref)
3223 const enum tree_code code = TREE_CODE (ref);
3230 return lvalue_p (TREE_OPERAND (ref, 0));
3232 case COMPOUND_LITERAL_EXPR:
3242 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3243 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3246 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3253 /* Give an error for storing in something that is 'const'. */
3256 readonly_error (tree arg, enum lvalue_use use)
3258 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3260 /* Using this macro rather than (for example) arrays of messages
3261 ensures that all the format strings are checked at compile
3263 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3264 : (use == lv_increment ? (I) \
3265 : (use == lv_decrement ? (D) : (AS))))
3266 if (TREE_CODE (arg) == COMPONENT_REF)
3268 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3269 readonly_error (TREE_OPERAND (arg, 0), use);
3271 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3272 G_("increment of read-only member %qD"),
3273 G_("decrement of read-only member %qD"),
3274 G_("read-only member %qD used as %<asm%> output")),
3275 TREE_OPERAND (arg, 1));
3277 else if (TREE_CODE (arg) == VAR_DECL)
3278 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3279 G_("increment of read-only variable %qD"),
3280 G_("decrement of read-only variable %qD"),
3281 G_("read-only variable %qD used as %<asm%> output")),
3284 error (READONLY_MSG (G_("assignment of read-only location %qE"),
3285 G_("increment of read-only location %qE"),
3286 G_("decrement of read-only location %qE"),
3287 G_("read-only location %qE used as %<asm%> output")),
3292 /* Return nonzero if REF is an lvalue valid for this language;
3293 otherwise, print an error message and return zero. USE says
3294 how the lvalue is being used and so selects the error message. */
3297 lvalue_or_else (const_tree ref, enum lvalue_use use)
3299 int win = lvalue_p (ref);
3307 /* Mark EXP saying that we need to be able to take the
3308 address of it; it should not be allocated in a register.
3309 Returns true if successful. */
3312 c_mark_addressable (tree exp)
3317 switch (TREE_CODE (x))
3320 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3323 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3327 /* ... fall through ... */
3333 x = TREE_OPERAND (x, 0);
3336 case COMPOUND_LITERAL_EXPR:
3338 TREE_ADDRESSABLE (x) = 1;
3345 if (C_DECL_REGISTER (x)
3346 && DECL_NONLOCAL (x))
3348 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3351 ("global register variable %qD used in nested function", x);
3354 pedwarn ("register variable %qD used in nested function", x);
3356 else if (C_DECL_REGISTER (x))
3358 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3359 error ("address of global register variable %qD requested", x);
3361 error ("address of register variable %qD requested", x);
3367 TREE_ADDRESSABLE (x) = 1;
3374 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3377 build_conditional_expr (tree ifexp, tree op1, tree op2)
3381 enum tree_code code1;
3382 enum tree_code code2;
3383 tree result_type = NULL;
3384 tree orig_op1 = op1, orig_op2 = op2;
3386 /* Promote both alternatives. */
3388 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3389 op1 = default_conversion (op1);
3390 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3391 op2 = default_conversion (op2);
3393 if (TREE_CODE (ifexp) == ERROR_MARK
3394 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3395 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3396 return error_mark_node;
3398 type1 = TREE_TYPE (op1);
3399 code1 = TREE_CODE (type1);
3400 type2 = TREE_TYPE (op2);
3401 code2 = TREE_CODE (type2);
3403 /* C90 does not permit non-lvalue arrays in conditional expressions.
3404 In C99 they will be pointers by now. */
3405 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3407 error ("non-lvalue array in conditional expression");
3408 return error_mark_node;
3411 /* Quickly detect the usual case where op1 and op2 have the same type
3413 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3416 result_type = type1;
3418 result_type = TYPE_MAIN_VARIANT (type1);
3420 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3421 || code1 == COMPLEX_TYPE)
3422 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3423 || code2 == COMPLEX_TYPE))
3425 result_type = c_common_type (type1, type2);
3427 /* If -Wsign-compare, warn here if type1 and type2 have
3428 different signedness. We'll promote the signed to unsigned
3429 and later code won't know it used to be different.
3430 Do this check on the original types, so that explicit casts
3431 will be considered, but default promotions won't. */
3432 if (warn_sign_compare && !skip_evaluation)
3434 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3435 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3437 if (unsigned_op1 ^ unsigned_op2)
3441 /* Do not warn if the result type is signed, since the
3442 signed type will only be chosen if it can represent
3443 all the values of the unsigned type. */
3444 if (!TYPE_UNSIGNED (result_type))
3446 /* Do not warn if the signed quantity is an unsuffixed
3447 integer literal (or some static constant expression
3448 involving such literals) and it is non-negative. */
3449 else if ((unsigned_op2
3450 && tree_expr_nonnegative_warnv_p (op1, &ovf))
3452 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
3455 warning (OPT_Wsign_compare, "signed and unsigned type in conditional expression");
3459 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3461 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3462 pedwarn ("ISO C forbids conditional expr with only one void side");
3463 result_type = void_type_node;
3465 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3467 if (comp_target_types (type1, type2))
3468 result_type = common_pointer_type (type1, type2);
3469 else if (null_pointer_constant_p (orig_op1))
3470 result_type = qualify_type (type2, type1);
3471 else if (null_pointer_constant_p (orig_op2))
3472 result_type = qualify_type (type1, type2);
3473 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3475 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3476 pedwarn ("ISO C forbids conditional expr between "
3477 "%<void *%> and function pointer");
3478 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3479 TREE_TYPE (type2)));
3481 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3483 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3484 pedwarn ("ISO C forbids conditional expr between "
3485 "%<void *%> and function pointer");
3486 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3487 TREE_TYPE (type1)));
3491 pedwarn ("pointer type mismatch in conditional expression");
3492 result_type = build_pointer_type (void_type_node);
3495 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3497 if (!null_pointer_constant_p (orig_op2))
3498 pedwarn ("pointer/integer type mismatch in conditional expression");
3501 op2 = null_pointer_node;
3503 result_type = type1;
3505 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3507 if (!null_pointer_constant_p (orig_op1))
3508 pedwarn ("pointer/integer type mismatch in conditional expression");
3511 op1 = null_pointer_node;
3513 result_type = type2;
3518 if (flag_cond_mismatch)
3519 result_type = void_type_node;
3522 error ("type mismatch in conditional expression");
3523 return error_mark_node;
3527 /* Merge const and volatile flags of the incoming types. */
3529 = build_type_variant (result_type,
3530 TREE_READONLY (op1) || TREE_READONLY (op2),
3531 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3533 if (result_type != TREE_TYPE (op1))
3534 op1 = convert_and_check (result_type, op1);
3535 if (result_type != TREE_TYPE (op2))
3536 op2 = convert_and_check (result_type, op2);
3538 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3541 /* Return a compound expression that performs two expressions and
3542 returns the value of the second of them. */
3545 build_compound_expr (tree expr1, tree expr2)
3547 if (!TREE_SIDE_EFFECTS (expr1))
3549 /* The left-hand operand of a comma expression is like an expression
3550 statement: with -Wunused, we should warn if it doesn't have
3551 any side-effects, unless it was explicitly cast to (void). */
3552 if (warn_unused_value)
3554 if (VOID_TYPE_P (TREE_TYPE (expr1))
3555 && CONVERT_EXPR_P (expr1))
3557 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3558 && TREE_CODE (expr1) == COMPOUND_EXPR
3559 && CONVERT_EXPR_P (TREE_OPERAND (expr1, 1)))
3560 ; /* (void) a, (void) b, c */
3562 warning (OPT_Wunused_value,
3563 "left-hand operand of comma expression has no effect");
3567 /* With -Wunused, we should also warn if the left-hand operand does have
3568 side-effects, but computes a value which is not used. For example, in
3569 `foo() + bar(), baz()' the result of the `+' operator is not used,
3570 so we should issue a warning. */
3571 else if (warn_unused_value)
3572 warn_if_unused_value (expr1, input_location);
3574 if (expr2 == error_mark_node)
3575 return error_mark_node;
3577 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3580 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3583 build_c_cast (tree type, tree expr)
3587 if (type == error_mark_node || expr == error_mark_node)
3588 return error_mark_node;
3590 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3591 only in <protocol> qualifications. But when constructing cast expressions,
3592 the protocols do matter and must be kept around. */
3593 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3594 return build1 (NOP_EXPR, type, expr);
3596 type = TYPE_MAIN_VARIANT (type);
3598 if (TREE_CODE (type) == ARRAY_TYPE)
3600 error ("cast specifies array type");
3601 return error_mark_node;
3604 if (TREE_CODE (type) == FUNCTION_TYPE)
3606 error ("cast specifies function type");
3607 return error_mark_node;
3610 if (!VOID_TYPE_P (type))
3612 value = require_complete_type (value);
3613 if (value == error_mark_node)
3614 return error_mark_node;
3617 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3621 if (TREE_CODE (type) == RECORD_TYPE
3622 || TREE_CODE (type) == UNION_TYPE)
3623 pedwarn ("ISO C forbids casting nonscalar to the same type");
3626 else if (TREE_CODE (type) == UNION_TYPE)
3630 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3631 if (TREE_TYPE (field) != error_mark_node
3632 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3633 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3641 pedwarn ("ISO C forbids casts to union type");
3642 t = digest_init (type,
3643 build_constructor_single (type, field, value),
3645 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3648 error ("cast to union type from type not present in union");
3649 return error_mark_node;
3655 if (type == void_type_node)
3656 return build1 (CONVERT_EXPR, type, value);
3658 otype = TREE_TYPE (value);
3660 /* Optionally warn about potentially worrisome casts. */
3663 && TREE_CODE (type) == POINTER_TYPE
3664 && TREE_CODE (otype) == POINTER_TYPE)
3666 tree in_type = type;
3667 tree in_otype = otype;
3671 /* Check that the qualifiers on IN_TYPE are a superset of
3672 the qualifiers of IN_OTYPE. The outermost level of
3673 POINTER_TYPE nodes is uninteresting and we stop as soon
3674 as we hit a non-POINTER_TYPE node on either type. */
3677 in_otype = TREE_TYPE (in_otype);
3678 in_type = TREE_TYPE (in_type);
3680 /* GNU C allows cv-qualified function types. 'const'
3681 means the function is very pure, 'volatile' means it
3682 can't return. We need to warn when such qualifiers
3683 are added, not when they're taken away. */
3684 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3685 && TREE_CODE (in_type) == FUNCTION_TYPE)
3686 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3688 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3690 while (TREE_CODE (in_type) == POINTER_TYPE
3691 && TREE_CODE (in_otype) == POINTER_TYPE);
3694 warning (OPT_Wcast_qual, "cast adds new qualifiers to function type");
3697 /* There are qualifiers present in IN_OTYPE that are not
3698 present in IN_TYPE. */
3699 warning (OPT_Wcast_qual, "cast discards qualifiers from pointer target type");
3702 /* Warn about possible alignment problems. */
3703 if (STRICT_ALIGNMENT
3704 && TREE_CODE (type) == POINTER_TYPE
3705 && TREE_CODE (otype) == POINTER_TYPE
3706 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3707 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3708 /* Don't warn about opaque types, where the actual alignment
3709 restriction is unknown. */
3710 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3711 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3712 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3713 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3714 warning (OPT_Wcast_align,
3715 "cast increases required alignment of target type");
3717 if (TREE_CODE (type) == INTEGER_TYPE
3718 && TREE_CODE (otype) == POINTER_TYPE
3719 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3720 /* Unlike conversion of integers to pointers, where the
3721 warning is disabled for converting constants because
3722 of cases such as SIG_*, warn about converting constant
3723 pointers to integers. In some cases it may cause unwanted
3724 sign extension, and a warning is appropriate. */
3725 warning (OPT_Wpointer_to_int_cast,
3726 "cast from pointer to integer of different size");
3728 if (TREE_CODE (value) == CALL_EXPR
3729 && TREE_CODE (type) != TREE_CODE (otype))
3730 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3731 "to non-matching type %qT", otype, type);
3733 if (TREE_CODE (type) == POINTER_TYPE
3734 && TREE_CODE (otype) == INTEGER_TYPE
3735 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3736 /* Don't warn about converting any constant. */
3737 && !TREE_CONSTANT (value))
3738 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3739 "of different size");
3741 if (warn_strict_aliasing <= 2)
3742 strict_aliasing_warning (otype, type, expr);
3744 /* If pedantic, warn for conversions between function and object
3745 pointer types, except for converting a null pointer constant
3746 to function pointer type. */
3748 && TREE_CODE (type) == POINTER_TYPE
3749 && TREE_CODE (otype) == POINTER_TYPE
3750 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3751 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3752 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3755 && TREE_CODE (type) == POINTER_TYPE
3756 && TREE_CODE (otype) == POINTER_TYPE
3757 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3758 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3759 && !null_pointer_constant_p (value))
3760 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3763 value = convert (type, value);
3765 /* Ignore any integer overflow caused by the cast. */
3766 if (TREE_CODE (value) == INTEGER_CST)
3768 if (CONSTANT_CLASS_P (ovalue) && TREE_OVERFLOW (ovalue))
3770 if (!TREE_OVERFLOW (value))
3772 /* Avoid clobbering a shared constant. */
3773 value = copy_node (value);
3774 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3777 else if (TREE_OVERFLOW (value))
3778 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3779 value = build_int_cst_wide (TREE_TYPE (value),
3780 TREE_INT_CST_LOW (value),
3781 TREE_INT_CST_HIGH (value));
3785 /* Don't let a cast be an lvalue. */
3787 value = non_lvalue (value);
3792 /* Interpret a cast of expression EXPR to type TYPE. */
3794 c_cast_expr (struct c_type_name *type_name, tree expr)
3797 int saved_wsp = warn_strict_prototypes;
3799 /* This avoids warnings about unprototyped casts on
3800 integers. E.g. "#define SIG_DFL (void(*)())0". */
3801 if (TREE_CODE (expr) == INTEGER_CST)
3802 warn_strict_prototypes = 0;
3803 type = groktypename (type_name);
3804 warn_strict_prototypes = saved_wsp;
3806 return build_c_cast (type, expr);
3809 /* Build an assignment expression of lvalue LHS from value RHS.
3810 MODIFYCODE is the code for a binary operator that we use
3811 to combine the old value of LHS with RHS to get the new value.
3812 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3815 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3819 tree lhstype = TREE_TYPE (lhs);
3820 tree olhstype = lhstype;
3822 /* Types that aren't fully specified cannot be used in assignments. */
3823 lhs = require_complete_type (lhs);
3825 /* Avoid duplicate error messages from operands that had errors. */
3826 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3827 return error_mark_node;
3829 if (!lvalue_or_else (lhs, lv_assign))
3830 return error_mark_node;
3832 STRIP_TYPE_NOPS (rhs);
3836 /* If a binary op has been requested, combine the old LHS value with the RHS
3837 producing the value we should actually store into the LHS. */
3839 if (modifycode != NOP_EXPR)
3841 lhs = stabilize_reference (lhs);
3842 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3845 /* Give an error for storing in something that is 'const'. */
3847 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3848 || ((TREE_CODE (lhstype) == RECORD_TYPE
3849 || TREE_CODE (lhstype) == UNION_TYPE)
3850 && C_TYPE_FIELDS_READONLY (lhstype)))
3852 readonly_error (lhs, lv_assign);
3853 return error_mark_node;
3856 /* If storing into a structure or union member,
3857 it has probably been given type `int'.
3858 Compute the type that would go with
3859 the actual amount of storage the member occupies. */
3861 if (TREE_CODE (lhs) == COMPONENT_REF
3862 && (TREE_CODE (lhstype) == INTEGER_TYPE
3863 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3864 || TREE_CODE (lhstype) == REAL_TYPE
3865 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3866 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3868 /* If storing in a field that is in actuality a short or narrower than one,
3869 we must store in the field in its actual type. */
3871 if (lhstype != TREE_TYPE (lhs))
3873 lhs = copy_node (lhs);
3874 TREE_TYPE (lhs) = lhstype;
3877 /* Convert new value to destination type. */
3879 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3880 NULL_TREE, NULL_TREE, 0);
3881 if (TREE_CODE (newrhs) == ERROR_MARK)
3882 return error_mark_node;
3884 /* Emit ObjC write barrier, if necessary. */
3885 if (c_dialect_objc () && flag_objc_gc)
3887 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3892 /* Scan operands. */
3894 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3895 TREE_SIDE_EFFECTS (result) = 1;
3897 /* If we got the LHS in a different type for storing in,
3898 convert the result back to the nominal type of LHS
3899 so that the value we return always has the same type
3900 as the LHS argument. */
3902 if (olhstype == TREE_TYPE (result))
3904 return convert_for_assignment (olhstype, result, ic_assign,
3905 NULL_TREE, NULL_TREE, 0);
3908 /* Convert value RHS to type TYPE as preparation for an assignment
3909 to an lvalue of type TYPE.
3910 The real work of conversion is done by `convert'.
3911 The purpose of this function is to generate error messages
3912 for assignments that are not allowed in C.
3913 ERRTYPE says whether it is argument passing, assignment,
3914 initialization or return.
3916 FUNCTION is a tree for the function being called.
3917 PARMNUM is the number of the argument, for printing in error messages. */
3920 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3921 tree fundecl, tree function, int parmnum)
3923 enum tree_code codel = TREE_CODE (type);
3925 enum tree_code coder;
3926 tree rname = NULL_TREE;
3927 bool objc_ok = false;
3929 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3932 /* Change pointer to function to the function itself for
3934 if (TREE_CODE (function) == ADDR_EXPR
3935 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3936 function = TREE_OPERAND (function, 0);
3938 /* Handle an ObjC selector specially for diagnostics. */
3939 selector = objc_message_selector ();
3941 if (selector && parmnum > 2)
3948 /* This macro is used to emit diagnostics to ensure that all format
3949 strings are complete sentences, visible to gettext and checked at
3951 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3956 pedwarn (AR, parmnum, rname); \
3958 case ic_argpass_nonproto: \
3959 warning (0, AR, parmnum, rname); \
3971 gcc_unreachable (); \
3975 STRIP_TYPE_NOPS (rhs);
3977 if (optimize && TREE_CODE (rhs) == VAR_DECL
3978 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3979 rhs = decl_constant_value_for_broken_optimization (rhs);
3981 rhstype = TREE_TYPE (rhs);
3982 coder = TREE_CODE (rhstype);
3984 if (coder == ERROR_MARK)
3985 return error_mark_node;
3987 if (c_dialect_objc ())
4010 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
4013 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4016 if (coder == VOID_TYPE)
4018 /* Except for passing an argument to an unprototyped function,
4019 this is a constraint violation. When passing an argument to
4020 an unprototyped function, it is compile-time undefined;
4021 making it a constraint in that case was rejected in
4023 error ("void value not ignored as it ought to be");
4024 return error_mark_node;
4026 rhs = require_complete_type (rhs);
4027 if (rhs == error_mark_node)
4028 return error_mark_node;
4029 /* A type converts to a reference to it.
4030 This code doesn't fully support references, it's just for the
4031 special case of va_start and va_copy. */
4032 if (codel == REFERENCE_TYPE
4033 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
4035 if (!lvalue_p (rhs))
4037 error ("cannot pass rvalue to reference parameter");
4038 return error_mark_node;
4040 if (!c_mark_addressable (rhs))
4041 return error_mark_node;
4042 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
4044 /* We already know that these two types are compatible, but they
4045 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4046 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4047 likely to be va_list, a typedef to __builtin_va_list, which
4048 is different enough that it will cause problems later. */
4049 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
4050 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
4052 rhs = build1 (NOP_EXPR, type, rhs);
4055 /* Some types can interconvert without explicit casts. */
4056 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
4057 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
4058 return convert (type, rhs);
4059 /* Arithmetic types all interconvert, and enum is treated like int. */
4060 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
4061 || codel == FIXED_POINT_TYPE
4062 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
4063 || codel == BOOLEAN_TYPE)
4064 && (coder == INTEGER_TYPE || coder == REAL_TYPE
4065 || coder == FIXED_POINT_TYPE
4066 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
4067 || coder == BOOLEAN_TYPE))
4068 return convert_and_check (type, rhs);
4070 /* Aggregates in different TUs might need conversion. */
4071 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
4073 && comptypes (type, rhstype))
4074 return convert_and_check (type, rhs);
4076 /* Conversion to a transparent union from its member types.
4077 This applies only to function arguments. */
4078 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
4079 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
4081 tree memb, marginal_memb = NULL_TREE;
4083 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
4085 tree memb_type = TREE_TYPE (memb);
4087 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
4088 TYPE_MAIN_VARIANT (rhstype)))
4091 if (TREE_CODE (memb_type) != POINTER_TYPE)
4094 if (coder == POINTER_TYPE)
4096 tree ttl = TREE_TYPE (memb_type);
4097 tree ttr = TREE_TYPE (rhstype);
4099 /* Any non-function converts to a [const][volatile] void *
4100 and vice versa; otherwise, targets must be the same.
4101 Meanwhile, the lhs target must have all the qualifiers of
4103 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4104 || comp_target_types (memb_type, rhstype))
4106 /* If this type won't generate any warnings, use it. */
4107 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
4108 || ((TREE_CODE (ttr) == FUNCTION_TYPE
4109 && TREE_CODE (ttl) == FUNCTION_TYPE)
4110 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4111 == TYPE_QUALS (ttr))
4112 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
4113 == TYPE_QUALS (ttl))))
4116 /* Keep looking for a better type, but remember this one. */
4118 marginal_memb = memb;
4122 /* Can convert integer zero to any pointer type. */
4123 if (null_pointer_constant_p (rhs))
4125 rhs = null_pointer_node;
4130 if (memb || marginal_memb)
4134 /* We have only a marginally acceptable member type;
4135 it needs a warning. */
4136 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
4137 tree ttr = TREE_TYPE (rhstype);
4139 /* Const and volatile mean something different for function
4140 types, so the usual warnings are not appropriate. */
4141 if (TREE_CODE (ttr) == FUNCTION_TYPE
4142 && TREE_CODE (ttl) == FUNCTION_TYPE)
4144 /* Because const and volatile on functions are
4145 restrictions that say the function will not do
4146 certain things, it is okay to use a const or volatile
4147 function where an ordinary one is wanted, but not
4149 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4150 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
4151 "makes qualified function "
4152 "pointer from unqualified"),
4153 G_("assignment makes qualified "
4154 "function pointer from "
4156 G_("initialization makes qualified "
4157 "function pointer from "
4159 G_("return makes qualified function "
4160 "pointer from unqualified"));
4162 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4163 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4164 "qualifiers from pointer target type"),
4165 G_("assignment discards qualifiers "
4166 "from pointer target type"),
4167 G_("initialization discards qualifiers "
4168 "from pointer target type"),
4169 G_("return discards qualifiers from "
4170 "pointer target type"));
4172 memb = marginal_memb;
4175 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
4176 pedwarn ("ISO C prohibits argument conversion to union type");
4178 rhs = fold_convert (TREE_TYPE (memb), rhs);
4179 return build_constructor_single (type, memb, rhs);
4183 /* Conversions among pointers */
4184 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4185 && (coder == codel))
4187 tree ttl = TREE_TYPE (type);
4188 tree ttr = TREE_TYPE (rhstype);
4191 bool is_opaque_pointer;
4192 int target_cmp = 0; /* Cache comp_target_types () result. */
4194 if (TREE_CODE (mvl) != ARRAY_TYPE)
4195 mvl = TYPE_MAIN_VARIANT (mvl);
4196 if (TREE_CODE (mvr) != ARRAY_TYPE)
4197 mvr = TYPE_MAIN_VARIANT (mvr);
4198 /* Opaque pointers are treated like void pointers. */
4199 is_opaque_pointer = vector_targets_convertible_p (ttl, ttr);
4201 /* C++ does not allow the implicit conversion void* -> T*. However,
4202 for the purpose of reducing the number of false positives, we
4203 tolerate the special case of
4207 where NULL is typically defined in C to be '(void *) 0'. */
4208 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4209 warning (OPT_Wc___compat, "request for implicit conversion from "
4210 "%qT to %qT not permitted in C++", rhstype, type);
4212 /* Check if the right-hand side has a format attribute but the
4213 left-hand side doesn't. */
4214 if (warn_missing_format_attribute
4215 && check_missing_format_attribute (type, rhstype))
4220 case ic_argpass_nonproto:
4221 warning (OPT_Wmissing_format_attribute,
4222 "argument %d of %qE might be "
4223 "a candidate for a format attribute",
4227 warning (OPT_Wmissing_format_attribute,
4228 "assignment left-hand side might be "
4229 "a candidate for a format attribute");
4232 warning (OPT_Wmissing_format_attribute,
4233 "initialization left-hand side might be "
4234 "a candidate for a format attribute");
4237 warning (OPT_Wmissing_format_attribute,
4238 "return type might be "
4239 "a candidate for a format attribute");
4246 /* Any non-function converts to a [const][volatile] void *
4247 and vice versa; otherwise, targets must be the same.
4248 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4249 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4250 || (target_cmp = comp_target_types (type, rhstype))
4251 || is_opaque_pointer
4252 || (c_common_unsigned_type (mvl)
4253 == c_common_unsigned_type (mvr)))
4256 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4259 && !null_pointer_constant_p (rhs)
4260 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4261 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4262 "%qE between function pointer "
4264 G_("ISO C forbids assignment between "
4265 "function pointer and %<void *%>"),
4266 G_("ISO C forbids initialization between "
4267 "function pointer and %<void *%>"),
4268 G_("ISO C forbids return between function "
4269 "pointer and %<void *%>"));
4270 /* Const and volatile mean something different for function types,
4271 so the usual warnings are not appropriate. */
4272 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4273 && TREE_CODE (ttl) != FUNCTION_TYPE)
4275 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4277 /* Types differing only by the presence of the 'volatile'
4278 qualifier are acceptable if the 'volatile' has been added
4279 in by the Objective-C EH machinery. */
4280 if (!objc_type_quals_match (ttl, ttr))
4281 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4282 "qualifiers from pointer target type"),
4283 G_("assignment discards qualifiers "
4284 "from pointer target type"),
4285 G_("initialization discards qualifiers "
4286 "from pointer target type"),
4287 G_("return discards qualifiers from "
4288 "pointer target type"));
4290 /* If this is not a case of ignoring a mismatch in signedness,
4292 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4295 /* If there is a mismatch, do warn. */
4296 else if (warn_pointer_sign)
4297 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4298 "%d of %qE differ in signedness"),
4299 G_("pointer targets in assignment "
4300 "differ in signedness"),
4301 G_("pointer targets in initialization "
4302 "differ in signedness"),
4303 G_("pointer targets in return differ "
4306 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4307 && TREE_CODE (ttr) == FUNCTION_TYPE)
4309 /* Because const and volatile on functions are restrictions
4310 that say the function will not do certain things,
4311 it is okay to use a const or volatile function
4312 where an ordinary one is wanted, but not vice-versa. */
4313 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4314 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4315 "qualified function pointer "
4316 "from unqualified"),
4317 G_("assignment makes qualified function "
4318 "pointer from unqualified"),
4319 G_("initialization makes qualified "
4320 "function pointer from unqualified"),
4321 G_("return makes qualified function "
4322 "pointer from unqualified"));
4326 /* Avoid warning about the volatile ObjC EH puts on decls. */
4328 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4329 "incompatible pointer type"),
4330 G_("assignment from incompatible pointer type"),
4331 G_("initialization from incompatible "
4333 G_("return from incompatible pointer type"));
4335 return convert (type, rhs);
4337 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4339 /* ??? This should not be an error when inlining calls to
4340 unprototyped functions. */
4341 error ("invalid use of non-lvalue array");
4342 return error_mark_node;
4344 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4346 /* An explicit constant 0 can convert to a pointer,
4347 or one that results from arithmetic, even including
4348 a cast to integer type. */
4349 if (!null_pointer_constant_p (rhs))
4350 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4351 "pointer from integer without a cast"),
4352 G_("assignment makes pointer from integer "
4354 G_("initialization makes pointer from "
4355 "integer without a cast"),
4356 G_("return makes pointer from integer "
4359 return convert (type, rhs);
4361 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4363 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4364 "from pointer without a cast"),
4365 G_("assignment makes integer from pointer "
4367 G_("initialization makes integer from pointer "
4369 G_("return makes integer from pointer "
4371 return convert (type, rhs);
4373 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4374 return convert (type, rhs);
4379 case ic_argpass_nonproto:
4380 /* ??? This should not be an error when inlining calls to
4381 unprototyped functions. */
4382 error ("incompatible type for argument %d of %qE", parmnum, rname);
4385 error ("incompatible types in assignment");
4388 error ("incompatible types in initialization");
4391 error ("incompatible types in return");
4397 return error_mark_node;
4400 /* If VALUE is a compound expr all of whose expressions are constant, then
4401 return its value. Otherwise, return error_mark_node.
4403 This is for handling COMPOUND_EXPRs as initializer elements
4404 which is allowed with a warning when -pedantic is specified. */
4407 valid_compound_expr_initializer (tree value, tree endtype)
4409 if (TREE_CODE (value) == COMPOUND_EXPR)
4411 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4413 return error_mark_node;
4414 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4417 else if (!initializer_constant_valid_p (value, endtype))
4418 return error_mark_node;
4423 /* Perform appropriate conversions on the initial value of a variable,
4424 store it in the declaration DECL,
4425 and print any error messages that are appropriate.
4426 If the init is invalid, store an ERROR_MARK. */
4429 store_init_value (tree decl, tree init)
4433 /* If variable's type was invalidly declared, just ignore it. */
4435 type = TREE_TYPE (decl);
4436 if (TREE_CODE (type) == ERROR_MARK)
4439 /* Digest the specified initializer into an expression. */
4441 value = digest_init (type, init, true, TREE_STATIC (decl));
4443 /* Store the expression if valid; else report error. */
4445 if (!in_system_header
4446 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4447 warning (OPT_Wtraditional, "traditional C rejects automatic "
4448 "aggregate initialization");
4450 DECL_INITIAL (decl) = value;
4452 /* ANSI wants warnings about out-of-range constant initializers. */
4453 STRIP_TYPE_NOPS (value);
4454 if (TREE_STATIC (decl))
4455 constant_expression_warning (value);
4457 /* Check if we need to set array size from compound literal size. */
4458 if (TREE_CODE (type) == ARRAY_TYPE
4459 && TYPE_DOMAIN (type) == 0
4460 && value != error_mark_node)
4462 tree inside_init = init;
4464 STRIP_TYPE_NOPS (inside_init);
4465 inside_init = fold (inside_init);
4467 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4469 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4471 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4473 /* For int foo[] = (int [3]){1}; we need to set array size
4474 now since later on array initializer will be just the
4475 brace enclosed list of the compound literal. */
4476 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4477 TREE_TYPE (decl) = type;
4478 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4480 layout_decl (cldecl, 0);
4486 /* Methods for storing and printing names for error messages. */
4488 /* Implement a spelling stack that allows components of a name to be pushed
4489 and popped. Each element on the stack is this structure. */
4496 unsigned HOST_WIDE_INT i;
4501 #define SPELLING_STRING 1
4502 #define SPELLING_MEMBER 2
4503 #define SPELLING_BOUNDS 3
4505 static struct spelling *spelling; /* Next stack element (unused). */
4506 static struct spelling *spelling_base; /* Spelling stack base. */
4507 static int spelling_size; /* Size of the spelling stack. */
4509 /* Macros to save and restore the spelling stack around push_... functions.
4510 Alternative to SAVE_SPELLING_STACK. */
4512 #define SPELLING_DEPTH() (spelling - spelling_base)
4513 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4515 /* Push an element on the spelling stack with type KIND and assign VALUE
4518 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4520 int depth = SPELLING_DEPTH (); \
4522 if (depth >= spelling_size) \
4524 spelling_size += 10; \
4525 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4527 RESTORE_SPELLING_DEPTH (depth); \
4530 spelling->kind = (KIND); \
4531 spelling->MEMBER = (VALUE); \
4535 /* Push STRING on the stack. Printed literally. */
4538 push_string (const char *string)
4540 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4543 /* Push a member name on the stack. Printed as '.' STRING. */
4546 push_member_name (tree decl)
4548 const char *const string
4549 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4550 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4553 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4556 push_array_bounds (unsigned HOST_WIDE_INT bounds)
4558 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4561 /* Compute the maximum size in bytes of the printed spelling. */
4564 spelling_length (void)
4569 for (p = spelling_base; p < spelling; p++)
4571 if (p->kind == SPELLING_BOUNDS)
4574 size += strlen (p->u.s) + 1;
4580 /* Print the spelling to BUFFER and return it. */
4583 print_spelling (char *buffer)
4588 for (p = spelling_base; p < spelling; p++)
4589 if (p->kind == SPELLING_BOUNDS)
4591 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4597 if (p->kind == SPELLING_MEMBER)
4599 for (s = p->u.s; (*d = *s++); d++)
4606 /* Issue an error message for a bad initializer component.
4607 MSGID identifies the message.
4608 The component name is taken from the spelling stack. */
4611 error_init (const char *msgid)
4615 error ("%s", _(msgid));
4616 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4618 error ("(near initialization for %qs)", ofwhat);
4621 /* Issue a pedantic warning for a bad initializer component.
4622 MSGID identifies the message.
4623 The component name is taken from the spelling stack. */
4626 pedwarn_init (const char *msgid)
4630 pedwarn ("%s", _(msgid));
4631 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4633 pedwarn ("(near initialization for %qs)", ofwhat);
4636 /* Issue a warning for a bad initializer component.
4638 OPT is the OPT_W* value corresponding to the warning option that
4639 controls this warning. MSGID identifies the message. The
4640 component name is taken from the spelling stack. */
4643 warning_init (int opt, const char *msgid)
4647 warning (opt, "%s", _(msgid));
4648 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4650 warning (opt, "(near initialization for %qs)", ofwhat);
4653 /* If TYPE is an array type and EXPR is a parenthesized string
4654 constant, warn if pedantic that EXPR is being used to initialize an
4655 object of type TYPE. */
4658 maybe_warn_string_init (tree type, struct c_expr expr)
4661 && TREE_CODE (type) == ARRAY_TYPE
4662 && TREE_CODE (expr.value) == STRING_CST
4663 && expr.original_code != STRING_CST)
4664 pedwarn_init ("array initialized from parenthesized string constant");
4667 /* Digest the parser output INIT as an initializer for type TYPE.
4668 Return a C expression of type TYPE to represent the initial value.
4670 If INIT is a string constant, STRICT_STRING is true if it is
4671 unparenthesized or we should not warn here for it being parenthesized.
4672 For other types of INIT, STRICT_STRING is not used.
4674 REQUIRE_CONSTANT requests an error if non-constant initializers or
4675 elements are seen. */
4678 digest_init (tree type, tree init, bool strict_string, int require_constant)
4680 enum tree_code code = TREE_CODE (type);
4681 tree inside_init = init;
4683 if (type == error_mark_node
4685 || init == error_mark_node
4686 || TREE_TYPE (init) == error_mark_node)
4687 return error_mark_node;
4689 STRIP_TYPE_NOPS (inside_init);
4691 inside_init = fold (inside_init);
4693 /* Initialization of an array of chars from a string constant
4694 optionally enclosed in braces. */
4696 if (code == ARRAY_TYPE && inside_init
4697 && TREE_CODE (inside_init) == STRING_CST)
4699 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4700 /* Note that an array could be both an array of character type
4701 and an array of wchar_t if wchar_t is signed char or unsigned
4703 bool char_array = (typ1 == char_type_node
4704 || typ1 == signed_char_type_node
4705 || typ1 == unsigned_char_type_node);
4706 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4707 bool char16_array = !!comptypes (typ1, char16_type_node);
4708 bool char32_array = !!comptypes (typ1, char32_type_node);
4710 if (char_array || wchar_array || char16_array || char32_array)
4713 tree typ2 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)));
4714 expr.value = inside_init;
4715 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4716 maybe_warn_string_init (type, expr);
4718 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4719 TYPE_MAIN_VARIANT (type)))
4724 if (typ2 != char_type_node)
4726 error_init ("char-array initialized from wide string");
4727 return error_mark_node;
4732 if (typ2 == char_type_node)
4734 error_init ("wide character array initialized from non-wide "
4736 return error_mark_node;
4738 else if (!comptypes(typ1, typ2))
4740 error_init ("wide character array initialized from "
4741 "incompatible wide string");
4742 return error_mark_node;
4746 TREE_TYPE (inside_init) = type;
4747 if (TYPE_DOMAIN (type) != 0
4748 && TYPE_SIZE (type) != 0
4749 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4750 /* Subtract the size of a single (possibly wide) character
4751 because it's ok to ignore the terminating null char
4752 that is counted in the length of the constant. */
4753 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4754 TREE_STRING_LENGTH (inside_init)
4755 - (TYPE_PRECISION (typ1)
4757 pedwarn_init ("initializer-string for array of chars is too long");
4761 else if (INTEGRAL_TYPE_P (typ1))
4763 error_init ("array of inappropriate type initialized "
4764 "from string constant");
4765 return error_mark_node;
4769 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4770 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4771 below and handle as a constructor. */
4772 if (code == VECTOR_TYPE
4773 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4774 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
4775 && TREE_CONSTANT (inside_init))
4777 if (TREE_CODE (inside_init) == VECTOR_CST
4778 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4779 TYPE_MAIN_VARIANT (type)))
4782 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4784 unsigned HOST_WIDE_INT ix;
4786 bool constant_p = true;
4788 /* Iterate through elements and check if all constructor
4789 elements are *_CSTs. */
4790 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4791 if (!CONSTANT_CLASS_P (value))
4798 return build_vector_from_ctor (type,
4799 CONSTRUCTOR_ELTS (inside_init));
4803 /* Any type can be initialized
4804 from an expression of the same type, optionally with braces. */
4806 if (inside_init && TREE_TYPE (inside_init) != 0
4807 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4808 TYPE_MAIN_VARIANT (type))
4809 || (code == ARRAY_TYPE
4810 && comptypes (TREE_TYPE (inside_init), type))
4811 || (code == VECTOR_TYPE
4812 && comptypes (TREE_TYPE (inside_init), type))
4813 || (code == POINTER_TYPE
4814 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4815 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4816 TREE_TYPE (type)))))
4818 if (code == POINTER_TYPE)
4820 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4822 if (TREE_CODE (inside_init) == STRING_CST
4823 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4824 inside_init = array_to_pointer_conversion (inside_init);
4827 error_init ("invalid use of non-lvalue array");
4828 return error_mark_node;
4833 if (code == VECTOR_TYPE)
4834 /* Although the types are compatible, we may require a
4836 inside_init = convert (type, inside_init);
4838 if (require_constant
4839 && (code == VECTOR_TYPE || !flag_isoc99)
4840 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4842 /* As an extension, allow initializing objects with static storage
4843 duration with compound literals (which are then treated just as
4844 the brace enclosed list they contain). Also allow this for
4845 vectors, as we can only assign them with compound literals. */
4846 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4847 inside_init = DECL_INITIAL (decl);
4850 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4851 && TREE_CODE (inside_init) != CONSTRUCTOR)
4853 error_init ("array initialized from non-constant array expression");
4854 return error_mark_node;
4857 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4858 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4860 /* Compound expressions can only occur here if -pedantic or
4861 -pedantic-errors is specified. In the later case, we always want
4862 an error. In the former case, we simply want a warning. */
4863 if (require_constant && pedantic
4864 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4867 = valid_compound_expr_initializer (inside_init,
4868 TREE_TYPE (inside_init));
4869 if (inside_init == error_mark_node)
4870 error_init ("initializer element is not constant");
4872 pedwarn_init ("initializer element is not constant");
4873 if (flag_pedantic_errors)
4874 inside_init = error_mark_node;
4876 else if (require_constant
4877 && !initializer_constant_valid_p (inside_init,
4878 TREE_TYPE (inside_init)))
4880 error_init ("initializer element is not constant");
4881 inside_init = error_mark_node;
4884 /* Added to enable additional -Wmissing-format-attribute warnings. */
4885 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4886 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4891 /* Handle scalar types, including conversions. */
4893 if (code == INTEGER_TYPE || code == REAL_TYPE || code == FIXED_POINT_TYPE
4894 || code == POINTER_TYPE || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE
4895 || code == COMPLEX_TYPE || code == VECTOR_TYPE)
4897 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4898 && (TREE_CODE (init) == STRING_CST
4899 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4900 init = array_to_pointer_conversion (init);
4902 = convert_for_assignment (type, init, ic_init,
4903 NULL_TREE, NULL_TREE, 0);
4905 /* Check to see if we have already given an error message. */
4906 if (inside_init == error_mark_node)
4908 else if (require_constant && !TREE_CONSTANT (inside_init))
4910 error_init ("initializer element is not constant");
4911 inside_init = error_mark_node;
4913 else if (require_constant
4914 && !initializer_constant_valid_p (inside_init,
4915 TREE_TYPE (inside_init)))
4917 error_init ("initializer element is not computable at load time");
4918 inside_init = error_mark_node;
4924 /* Come here only for records and arrays. */
4926 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4928 error_init ("variable-sized object may not be initialized");
4929 return error_mark_node;
4932 error_init ("invalid initializer");
4933 return error_mark_node;
4936 /* Handle initializers that use braces. */
4938 /* Type of object we are accumulating a constructor for.
4939 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4940 static tree constructor_type;
4942 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4944 static tree constructor_fields;
4946 /* For an ARRAY_TYPE, this is the specified index
4947 at which to store the next element we get. */
4948 static tree constructor_index;
4950 /* For an ARRAY_TYPE, this is the maximum index. */
4951 static tree constructor_max_index;
4953 /* For a RECORD_TYPE, this is the first field not yet written out. */
4954 static tree constructor_unfilled_fields;
4956 /* For an ARRAY_TYPE, this is the index of the first element
4957 not yet written out. */
4958 static tree constructor_unfilled_index;
4960 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4961 This is so we can generate gaps between fields, when appropriate. */
4962 static tree constructor_bit_index;
4964 /* If we are saving up the elements rather than allocating them,
4965 this is the list of elements so far (in reverse order,
4966 most recent first). */
4967 static VEC(constructor_elt,gc) *constructor_elements;
4969 /* 1 if constructor should be incrementally stored into a constructor chain,
4970 0 if all the elements should be kept in AVL tree. */
4971 static int constructor_incremental;
4973 /* 1 if so far this constructor's elements are all compile-time constants. */
4974 static int constructor_constant;
4976 /* 1 if so far this constructor's elements are all valid address constants. */
4977 static int constructor_simple;
4979 /* 1 if this constructor is erroneous so far. */
4980 static int constructor_erroneous;
4982 /* Structure for managing pending initializer elements, organized as an
4987 struct init_node *left, *right;
4988 struct init_node *parent;
4994 /* Tree of pending elements at this constructor level.
4995 These are elements encountered out of order
4996 which belong at places we haven't reached yet in actually
4998 Will never hold tree nodes across GC runs. */
4999 static struct init_node *constructor_pending_elts;
5001 /* The SPELLING_DEPTH of this constructor. */
5002 static int constructor_depth;
5004 /* DECL node for which an initializer is being read.
5005 0 means we are reading a constructor expression
5006 such as (struct foo) {...}. */
5007 static tree constructor_decl;
5009 /* Nonzero if this is an initializer for a top-level decl. */
5010 static int constructor_top_level;
5012 /* Nonzero if there were any member designators in this initializer. */
5013 static int constructor_designated;
5015 /* Nesting depth of designator list. */
5016 static int designator_depth;
5018 /* Nonzero if there were diagnosed errors in this designator list. */
5019 static int designator_erroneous;
5022 /* This stack has a level for each implicit or explicit level of
5023 structuring in the initializer, including the outermost one. It
5024 saves the values of most of the variables above. */
5026 struct constructor_range_stack;
5028 struct constructor_stack
5030 struct constructor_stack *next;
5035 tree unfilled_index;
5036 tree unfilled_fields;
5038 VEC(constructor_elt,gc) *elements;
5039 struct init_node *pending_elts;
5042 /* If value nonzero, this value should replace the entire
5043 constructor at this level. */
5044 struct c_expr replacement_value;
5045 struct constructor_range_stack *range_stack;
5055 static struct constructor_stack *constructor_stack;
5057 /* This stack represents designators from some range designator up to
5058 the last designator in the list. */
5060 struct constructor_range_stack
5062 struct constructor_range_stack *next, *prev;
5063 struct constructor_stack *stack;
5070 static struct constructor_range_stack *constructor_range_stack;
5072 /* This stack records separate initializers that are nested.
5073 Nested initializers can't happen in ANSI C, but GNU C allows them
5074 in cases like { ... (struct foo) { ... } ... }. */
5076 struct initializer_stack
5078 struct initializer_stack *next;
5080 struct constructor_stack *constructor_stack;
5081 struct constructor_range_stack *constructor_range_stack;
5082 VEC(constructor_elt,gc) *elements;
5083 struct spelling *spelling;
5084 struct spelling *spelling_base;
5087 char require_constant_value;
5088 char require_constant_elements;
5091 static struct initializer_stack *initializer_stack;
5093 /* Prepare to parse and output the initializer for variable DECL. */
5096 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
5099 struct initializer_stack *p = XNEW (struct initializer_stack);
5101 p->decl = constructor_decl;
5102 p->require_constant_value = require_constant_value;
5103 p->require_constant_elements = require_constant_elements;
5104 p->constructor_stack = constructor_stack;
5105 p->constructor_range_stack = constructor_range_stack;
5106 p->elements = constructor_elements;
5107 p->spelling = spelling;
5108 p->spelling_base = spelling_base;
5109 p->spelling_size = spelling_size;
5110 p->top_level = constructor_top_level;
5111 p->next = initializer_stack;
5112 initializer_stack = p;
5114 constructor_decl = decl;
5115 constructor_designated = 0;
5116 constructor_top_level = top_level;
5118 if (decl != 0 && decl != error_mark_node)
5120 require_constant_value = TREE_STATIC (decl);
5121 require_constant_elements
5122 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
5123 /* For a scalar, you can always use any value to initialize,
5124 even within braces. */
5125 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
5126 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
5127 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
5128 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
5129 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
5133 require_constant_value = 0;
5134 require_constant_elements = 0;
5135 locus = "(anonymous)";
5138 constructor_stack = 0;
5139 constructor_range_stack = 0;
5141 missing_braces_mentioned = 0;
5145 RESTORE_SPELLING_DEPTH (0);
5148 push_string (locus);
5154 struct initializer_stack *p = initializer_stack;
5156 /* Free the whole constructor stack of this initializer. */
5157 while (constructor_stack)
5159 struct constructor_stack *q = constructor_stack;
5160 constructor_stack = q->next;
5164 gcc_assert (!constructor_range_stack);
5166 /* Pop back to the data of the outer initializer (if any). */
5167 free (spelling_base);
5169 constructor_decl = p->decl;
5170 require_constant_value = p->require_constant_value;
5171 require_constant_elements = p->require_constant_elements;
5172 constructor_stack = p->constructor_stack;
5173 constructor_range_stack = p->constructor_range_stack;
5174 constructor_elements = p->elements;
5175 spelling = p->spelling;
5176 spelling_base = p->spelling_base;
5177 spelling_size = p->spelling_size;
5178 constructor_top_level = p->top_level;
5179 initializer_stack = p->next;
5183 /* Call here when we see the initializer is surrounded by braces.
5184 This is instead of a call to push_init_level;
5185 it is matched by a call to pop_init_level.
5187 TYPE is the type to initialize, for a constructor expression.
5188 For an initializer for a decl, TYPE is zero. */
5191 really_start_incremental_init (tree type)
5193 struct constructor_stack *p = XNEW (struct constructor_stack);
5196 type = TREE_TYPE (constructor_decl);
5198 if (targetm.vector_opaque_p (type))
5199 error ("opaque vector types cannot be initialized");
5201 p->type = constructor_type;
5202 p->fields = constructor_fields;
5203 p->index = constructor_index;
5204 p->max_index = constructor_max_index;
5205 p->unfilled_index = constructor_unfilled_index;
5206 p->unfilled_fields = constructor_unfilled_fields;
5207 p->bit_index = constructor_bit_index;
5208 p->elements = constructor_elements;
5209 p->constant = constructor_constant;
5210 p->simple = constructor_simple;
5211 p->erroneous = constructor_erroneous;
5212 p->pending_elts = constructor_pending_elts;
5213 p->depth = constructor_depth;
5214 p->replacement_value.value = 0;
5215 p->replacement_value.original_code = ERROR_MARK;
5219 p->incremental = constructor_incremental;
5220 p->designated = constructor_designated;
5222 constructor_stack = p;
5224 constructor_constant = 1;
5225 constructor_simple = 1;
5226 constructor_depth = SPELLING_DEPTH ();
5227 constructor_elements = 0;
5228 constructor_pending_elts = 0;
5229 constructor_type = type;
5230 constructor_incremental = 1;
5231 constructor_designated = 0;
5232 designator_depth = 0;
5233 designator_erroneous = 0;
5235 if (TREE_CODE (constructor_type) == RECORD_TYPE
5236 || TREE_CODE (constructor_type) == UNION_TYPE)
5238 constructor_fields = TYPE_FIELDS (constructor_type);
5239 /* Skip any nameless bit fields at the beginning. */
5240 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5241 && DECL_NAME (constructor_fields) == 0)
5242 constructor_fields = TREE_CHAIN (constructor_fields);
5244 constructor_unfilled_fields = constructor_fields;
5245 constructor_bit_index = bitsize_zero_node;
5247 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5249 if (TYPE_DOMAIN (constructor_type))
5251 constructor_max_index
5252 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5254 /* Detect non-empty initializations of zero-length arrays. */
5255 if (constructor_max_index == NULL_TREE
5256 && TYPE_SIZE (constructor_type))
5257 constructor_max_index = build_int_cst (NULL_TREE, -1);
5259 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5260 to initialize VLAs will cause a proper error; avoid tree
5261 checking errors as well by setting a safe value. */
5262 if (constructor_max_index
5263 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5264 constructor_max_index = build_int_cst (NULL_TREE, -1);
5267 = convert (bitsizetype,
5268 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5272 constructor_index = bitsize_zero_node;
5273 constructor_max_index = NULL_TREE;
5276 constructor_unfilled_index = constructor_index;
5278 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5280 /* Vectors are like simple fixed-size arrays. */
5281 constructor_max_index =
5282 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5283 constructor_index = bitsize_zero_node;
5284 constructor_unfilled_index = constructor_index;
5288 /* Handle the case of int x = {5}; */
5289 constructor_fields = constructor_type;
5290 constructor_unfilled_fields = constructor_type;
5294 /* Push down into a subobject, for initialization.
5295 If this is for an explicit set of braces, IMPLICIT is 0.
5296 If it is because the next element belongs at a lower level,
5297 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5300 push_init_level (int implicit)
5302 struct constructor_stack *p;
5303 tree value = NULL_TREE;
5305 /* If we've exhausted any levels that didn't have braces,
5306 pop them now. If implicit == 1, this will have been done in
5307 process_init_element; do not repeat it here because in the case
5308 of excess initializers for an empty aggregate this leads to an
5309 infinite cycle of popping a level and immediately recreating
5313 while (constructor_stack->implicit)
5315 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5316 || TREE_CODE (constructor_type) == UNION_TYPE)
5317 && constructor_fields == 0)
5318 process_init_element (pop_init_level (1));
5319 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5320 && constructor_max_index
5321 && tree_int_cst_lt (constructor_max_index,
5323 process_init_element (pop_init_level (1));
5329 /* Unless this is an explicit brace, we need to preserve previous
5333 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5334 || TREE_CODE (constructor_type) == UNION_TYPE)
5335 && constructor_fields)
5336 value = find_init_member (constructor_fields);
5337 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5338 value = find_init_member (constructor_index);
5341 p = XNEW (struct constructor_stack);
5342 p->type = constructor_type;
5343 p->fields = constructor_fields;
5344 p->index = constructor_index;
5345 p->max_index = constructor_max_index;
5346 p->unfilled_index = constructor_unfilled_index;
5347 p->unfilled_fields = constructor_unfilled_fields;
5348 p->bit_index = constructor_bit_index;
5349 p->elements = constructor_elements;
5350 p->constant = constructor_constant;
5351 p->simple = constructor_simple;
5352 p->erroneous = constructor_erroneous;
5353 p->pending_elts = constructor_pending_elts;
5354 p->depth = constructor_depth;
5355 p->replacement_value.value = 0;
5356 p->replacement_value.original_code = ERROR_MARK;
5357 p->implicit = implicit;
5359 p->incremental = constructor_incremental;
5360 p->designated = constructor_designated;
5361 p->next = constructor_stack;
5363 constructor_stack = p;
5365 constructor_constant = 1;
5366 constructor_simple = 1;
5367 constructor_depth = SPELLING_DEPTH ();
5368 constructor_elements = 0;
5369 constructor_incremental = 1;
5370 constructor_designated = 0;
5371 constructor_pending_elts = 0;
5374 p->range_stack = constructor_range_stack;
5375 constructor_range_stack = 0;
5376 designator_depth = 0;
5377 designator_erroneous = 0;
5380 /* Don't die if an entire brace-pair level is superfluous
5381 in the containing level. */
5382 if (constructor_type == 0)
5384 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5385 || TREE_CODE (constructor_type) == UNION_TYPE)
5387 /* Don't die if there are extra init elts at the end. */
5388 if (constructor_fields == 0)
5389 constructor_type = 0;
5392 constructor_type = TREE_TYPE (constructor_fields);
5393 push_member_name (constructor_fields);
5394 constructor_depth++;
5397 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5399 constructor_type = TREE_TYPE (constructor_type);
5400 push_array_bounds (tree_low_cst (constructor_index, 1));
5401 constructor_depth++;
5404 if (constructor_type == 0)
5406 error_init ("extra brace group at end of initializer");
5407 constructor_fields = 0;
5408 constructor_unfilled_fields = 0;
5412 if (value && TREE_CODE (value) == CONSTRUCTOR)
5414 constructor_constant = TREE_CONSTANT (value);
5415 constructor_simple = TREE_STATIC (value);
5416 constructor_elements = CONSTRUCTOR_ELTS (value);
5417 if (!VEC_empty (constructor_elt, constructor_elements)
5418 && (TREE_CODE (constructor_type) == RECORD_TYPE
5419 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5420 set_nonincremental_init ();
5423 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5425 missing_braces_mentioned = 1;
5426 warning_init (OPT_Wmissing_braces, "missing braces around initializer");
5429 if (TREE_CODE (constructor_type) == RECORD_TYPE
5430 || TREE_CODE (constructor_type) == UNION_TYPE)
5432 constructor_fields = TYPE_FIELDS (constructor_type);
5433 /* Skip any nameless bit fields at the beginning. */
5434 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5435 && DECL_NAME (constructor_fields) == 0)
5436 constructor_fields = TREE_CHAIN (constructor_fields);
5438 constructor_unfilled_fields = constructor_fields;
5439 constructor_bit_index = bitsize_zero_node;
5441 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5443 /* Vectors are like simple fixed-size arrays. */
5444 constructor_max_index =
5445 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5446 constructor_index = convert (bitsizetype, integer_zero_node);
5447 constructor_unfilled_index = constructor_index;
5449 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5451 if (TYPE_DOMAIN (constructor_type))
5453 constructor_max_index
5454 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5456 /* Detect non-empty initializations of zero-length arrays. */
5457 if (constructor_max_index == NULL_TREE
5458 && TYPE_SIZE (constructor_type))
5459 constructor_max_index = build_int_cst (NULL_TREE, -1);
5461 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5462 to initialize VLAs will cause a proper error; avoid tree
5463 checking errors as well by setting a safe value. */
5464 if (constructor_max_index
5465 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5466 constructor_max_index = build_int_cst (NULL_TREE, -1);
5469 = convert (bitsizetype,
5470 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5473 constructor_index = bitsize_zero_node;
5475 constructor_unfilled_index = constructor_index;
5476 if (value && TREE_CODE (value) == STRING_CST)
5478 /* We need to split the char/wchar array into individual
5479 characters, so that we don't have to special case it
5481 set_nonincremental_init_from_string (value);
5486 if (constructor_type != error_mark_node)
5487 warning_init (0, "braces around scalar initializer");
5488 constructor_fields = constructor_type;
5489 constructor_unfilled_fields = constructor_type;
5493 /* At the end of an implicit or explicit brace level,
5494 finish up that level of constructor. If a single expression
5495 with redundant braces initialized that level, return the
5496 c_expr structure for that expression. Otherwise, the original_code
5497 element is set to ERROR_MARK.
5498 If we were outputting the elements as they are read, return 0 as the value
5499 from inner levels (process_init_element ignores that),
5500 but return error_mark_node as the value from the outermost level
5501 (that's what we want to put in DECL_INITIAL).
5502 Otherwise, return a CONSTRUCTOR expression as the value. */
5505 pop_init_level (int implicit)
5507 struct constructor_stack *p;
5510 ret.original_code = ERROR_MARK;
5514 /* When we come to an explicit close brace,
5515 pop any inner levels that didn't have explicit braces. */
5516 while (constructor_stack->implicit)
5517 process_init_element (pop_init_level (1));
5519 gcc_assert (!constructor_range_stack);
5522 /* Now output all pending elements. */
5523 constructor_incremental = 1;
5524 output_pending_init_elements (1);
5526 p = constructor_stack;
5528 /* Error for initializing a flexible array member, or a zero-length
5529 array member in an inappropriate context. */
5530 if (constructor_type && constructor_fields
5531 && TREE_CODE (constructor_type) == ARRAY_TYPE
5532 && TYPE_DOMAIN (constructor_type)
5533 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5535 /* Silently discard empty initializations. The parser will
5536 already have pedwarned for empty brackets. */
5537 if (integer_zerop (constructor_unfilled_index))
5538 constructor_type = NULL_TREE;
5541 gcc_assert (!TYPE_SIZE (constructor_type));
5543 if (constructor_depth > 2)
5544 error_init ("initialization of flexible array member in a nested context");
5546 pedwarn_init ("initialization of a flexible array member");
5548 /* We have already issued an error message for the existence
5549 of a flexible array member not at the end of the structure.
5550 Discard the initializer so that we do not die later. */
5551 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5552 constructor_type = NULL_TREE;
5556 /* Warn when some struct elements are implicitly initialized to zero. */
5557 if (warn_missing_field_initializers
5559 && TREE_CODE (constructor_type) == RECORD_TYPE
5560 && constructor_unfilled_fields)
5562 /* Do not warn for flexible array members or zero-length arrays. */
5563 while (constructor_unfilled_fields
5564 && (!DECL_SIZE (constructor_unfilled_fields)
5565 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5566 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5568 /* Do not warn if this level of the initializer uses member
5569 designators; it is likely to be deliberate. */
5570 if (constructor_unfilled_fields && !constructor_designated)
5572 push_member_name (constructor_unfilled_fields);
5573 warning_init (OPT_Wmissing_field_initializers,
5574 "missing initializer");
5575 RESTORE_SPELLING_DEPTH (constructor_depth);
5579 /* Pad out the end of the structure. */
5580 if (p->replacement_value.value)
5581 /* If this closes a superfluous brace pair,
5582 just pass out the element between them. */
5583 ret = p->replacement_value;
5584 else if (constructor_type == 0)
5586 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5587 && TREE_CODE (constructor_type) != UNION_TYPE
5588 && TREE_CODE (constructor_type) != ARRAY_TYPE
5589 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5591 /* A nonincremental scalar initializer--just return
5592 the element, after verifying there is just one. */
5593 if (VEC_empty (constructor_elt,constructor_elements))
5595 if (!constructor_erroneous)
5596 error_init ("empty scalar initializer");
5597 ret.value = error_mark_node;
5599 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5601 error_init ("extra elements in scalar initializer");
5602 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5605 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5609 if (constructor_erroneous)
5610 ret.value = error_mark_node;
5613 ret.value = build_constructor (constructor_type,
5614 constructor_elements);
5615 if (constructor_constant)
5616 TREE_CONSTANT (ret.value) = 1;
5617 if (constructor_constant && constructor_simple)
5618 TREE_STATIC (ret.value) = 1;
5622 constructor_type = p->type;
5623 constructor_fields = p->fields;
5624 constructor_index = p->index;
5625 constructor_max_index = p->max_index;
5626 constructor_unfilled_index = p->unfilled_index;
5627 constructor_unfilled_fields = p->unfilled_fields;
5628 constructor_bit_index = p->bit_index;
5629 constructor_elements = p->elements;
5630 constructor_constant = p->constant;
5631 constructor_simple = p->simple;
5632 constructor_erroneous = p->erroneous;
5633 constructor_incremental = p->incremental;
5634 constructor_designated = p->designated;
5635 constructor_pending_elts = p->pending_elts;
5636 constructor_depth = p->depth;
5638 constructor_range_stack = p->range_stack;
5639 RESTORE_SPELLING_DEPTH (constructor_depth);
5641 constructor_stack = p->next;
5644 if (ret.value == 0 && constructor_stack == 0)
5645 ret.value = error_mark_node;
5649 /* Common handling for both array range and field name designators.
5650 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5653 set_designator (int array)
5656 enum tree_code subcode;
5658 /* Don't die if an entire brace-pair level is superfluous
5659 in the containing level. */
5660 if (constructor_type == 0)
5663 /* If there were errors in this designator list already, bail out
5665 if (designator_erroneous)
5668 if (!designator_depth)
5670 gcc_assert (!constructor_range_stack);
5672 /* Designator list starts at the level of closest explicit
5674 while (constructor_stack->implicit)
5675 process_init_element (pop_init_level (1));
5676 constructor_designated = 1;
5680 switch (TREE_CODE (constructor_type))
5684 subtype = TREE_TYPE (constructor_fields);
5685 if (subtype != error_mark_node)
5686 subtype = TYPE_MAIN_VARIANT (subtype);
5689 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5695 subcode = TREE_CODE (subtype);
5696 if (array && subcode != ARRAY_TYPE)
5698 error_init ("array index in non-array initializer");
5701 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5703 error_init ("field name not in record or union initializer");
5707 constructor_designated = 1;
5708 push_init_level (2);
5712 /* If there are range designators in designator list, push a new designator
5713 to constructor_range_stack. RANGE_END is end of such stack range or
5714 NULL_TREE if there is no range designator at this level. */
5717 push_range_stack (tree range_end)
5719 struct constructor_range_stack *p;
5721 p = GGC_NEW (struct constructor_range_stack);
5722 p->prev = constructor_range_stack;
5724 p->fields = constructor_fields;
5725 p->range_start = constructor_index;
5726 p->index = constructor_index;
5727 p->stack = constructor_stack;
5728 p->range_end = range_end;
5729 if (constructor_range_stack)
5730 constructor_range_stack->next = p;
5731 constructor_range_stack = p;
5734 /* Within an array initializer, specify the next index to be initialized.
5735 FIRST is that index. If LAST is nonzero, then initialize a range
5736 of indices, running from FIRST through LAST. */
5739 set_init_index (tree first, tree last)
5741 if (set_designator (1))
5744 designator_erroneous = 1;
5746 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5747 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5749 error_init ("array index in initializer not of integer type");
5753 if (TREE_CODE (first) != INTEGER_CST)
5754 error_init ("nonconstant array index in initializer");
5755 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5756 error_init ("nonconstant array index in initializer");
5757 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5758 error_init ("array index in non-array initializer");
5759 else if (tree_int_cst_sgn (first) == -1)
5760 error_init ("array index in initializer exceeds array bounds");
5761 else if (constructor_max_index
5762 && tree_int_cst_lt (constructor_max_index, first))
5763 error_init ("array index in initializer exceeds array bounds");
5766 constructor_index = convert (bitsizetype, first);
5770 if (tree_int_cst_equal (first, last))
5772 else if (tree_int_cst_lt (last, first))
5774 error_init ("empty index range in initializer");
5779 last = convert (bitsizetype, last);
5780 if (constructor_max_index != 0
5781 && tree_int_cst_lt (constructor_max_index, last))
5783 error_init ("array index range in initializer exceeds array bounds");
5790 designator_erroneous = 0;
5791 if (constructor_range_stack || last)
5792 push_range_stack (last);
5796 /* Within a struct initializer, specify the next field to be initialized. */
5799 set_init_label (tree fieldname)
5803 if (set_designator (0))
5806 designator_erroneous = 1;
5808 if (TREE_CODE (constructor_type) != RECORD_TYPE
5809 && TREE_CODE (constructor_type) != UNION_TYPE)
5811 error_init ("field name not in record or union initializer");
5815 for (tail = TYPE_FIELDS (constructor_type); tail;
5816 tail = TREE_CHAIN (tail))
5818 if (DECL_NAME (tail) == fieldname)
5823 error ("unknown field %qE specified in initializer", fieldname);
5826 constructor_fields = tail;
5828 designator_erroneous = 0;
5829 if (constructor_range_stack)
5830 push_range_stack (NULL_TREE);
5834 /* Add a new initializer to the tree of pending initializers. PURPOSE
5835 identifies the initializer, either array index or field in a structure.
5836 VALUE is the value of that index or field. */
5839 add_pending_init (tree purpose, tree value)
5841 struct init_node *p, **q, *r;
5843 q = &constructor_pending_elts;
5846 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5851 if (tree_int_cst_lt (purpose, p->purpose))
5853 else if (tree_int_cst_lt (p->purpose, purpose))
5857 if (TREE_SIDE_EFFECTS (p->value))
5858 warning_init (0, "initialized field with side-effects overwritten");
5859 else if (warn_override_init)
5860 warning_init (OPT_Woverride_init, "initialized field overwritten");
5870 bitpos = bit_position (purpose);
5874 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5876 else if (p->purpose != purpose)
5880 if (TREE_SIDE_EFFECTS (p->value))
5881 warning_init (0, "initialized field with side-effects overwritten");
5882 else if (warn_override_init)
5883 warning_init (OPT_Woverride_init, "initialized field overwritten");
5890 r = GGC_NEW (struct init_node);
5891 r->purpose = purpose;
5902 struct init_node *s;
5906 if (p->balance == 0)
5908 else if (p->balance < 0)
5915 p->left->parent = p;
5932 constructor_pending_elts = r;
5937 struct init_node *t = r->right;
5941 r->right->parent = r;
5946 p->left->parent = p;
5949 p->balance = t->balance < 0;
5950 r->balance = -(t->balance > 0);
5965 constructor_pending_elts = t;
5971 /* p->balance == +1; growth of left side balances the node. */
5976 else /* r == p->right */
5978 if (p->balance == 0)
5979 /* Growth propagation from right side. */
5981 else if (p->balance > 0)
5988 p->right->parent = p;
6005 constructor_pending_elts = r;
6007 else /* r->balance == -1 */
6010 struct init_node *t = r->left;
6014 r->left->parent = r;
6019 p->right->parent = p;
6022 r->balance = (t->balance < 0);
6023 p->balance = -(t->balance > 0);
6038 constructor_pending_elts = t;
6044 /* p->balance == -1; growth of right side balances the node. */
6055 /* Build AVL tree from a sorted chain. */
6058 set_nonincremental_init (void)
6060 unsigned HOST_WIDE_INT ix;
6063 if (TREE_CODE (constructor_type) != RECORD_TYPE
6064 && TREE_CODE (constructor_type) != ARRAY_TYPE)
6067 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
6068 add_pending_init (index, value);
6069 constructor_elements = 0;
6070 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6072 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
6073 /* Skip any nameless bit fields at the beginning. */
6074 while (constructor_unfilled_fields != 0
6075 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6076 && DECL_NAME (constructor_unfilled_fields) == 0)
6077 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
6080 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6082 if (TYPE_DOMAIN (constructor_type))
6083 constructor_unfilled_index
6084 = convert (bitsizetype,
6085 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
6087 constructor_unfilled_index = bitsize_zero_node;
6089 constructor_incremental = 0;
6092 /* Build AVL tree from a string constant. */
6095 set_nonincremental_init_from_string (tree str)
6097 tree value, purpose, type;
6098 HOST_WIDE_INT val[2];
6099 const char *p, *end;
6100 int byte, wchar_bytes, charwidth, bitpos;
6102 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
6104 wchar_bytes = TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) / BITS_PER_UNIT;
6105 charwidth = TYPE_PRECISION (char_type_node);
6106 type = TREE_TYPE (constructor_type);
6107 p = TREE_STRING_POINTER (str);
6108 end = p + TREE_STRING_LENGTH (str);
6110 for (purpose = bitsize_zero_node;
6111 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
6112 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
6114 if (wchar_bytes == 1)
6116 val[1] = (unsigned char) *p++;
6123 for (byte = 0; byte < wchar_bytes; byte++)
6125 if (BYTES_BIG_ENDIAN)
6126 bitpos = (wchar_bytes - byte - 1) * charwidth;
6128 bitpos = byte * charwidth;
6129 val[bitpos < HOST_BITS_PER_WIDE_INT]
6130 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
6131 << (bitpos % HOST_BITS_PER_WIDE_INT);
6135 if (!TYPE_UNSIGNED (type))
6137 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
6138 if (bitpos < HOST_BITS_PER_WIDE_INT)
6140 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
6142 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
6146 else if (bitpos == HOST_BITS_PER_WIDE_INT)
6151 else if (val[0] & (((HOST_WIDE_INT) 1)
6152 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
6153 val[0] |= ((HOST_WIDE_INT) -1)
6154 << (bitpos - HOST_BITS_PER_WIDE_INT);
6157 value = build_int_cst_wide (type, val[1], val[0]);
6158 add_pending_init (purpose, value);
6161 constructor_incremental = 0;
6164 /* Return value of FIELD in pending initializer or zero if the field was
6165 not initialized yet. */
6168 find_init_member (tree field)
6170 struct init_node *p;
6172 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6174 if (constructor_incremental
6175 && tree_int_cst_lt (field, constructor_unfilled_index))
6176 set_nonincremental_init ();
6178 p = constructor_pending_elts;
6181 if (tree_int_cst_lt (field, p->purpose))
6183 else if (tree_int_cst_lt (p->purpose, field))
6189 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6191 tree bitpos = bit_position (field);
6193 if (constructor_incremental
6194 && (!constructor_unfilled_fields
6195 || tree_int_cst_lt (bitpos,
6196 bit_position (constructor_unfilled_fields))))
6197 set_nonincremental_init ();
6199 p = constructor_pending_elts;
6202 if (field == p->purpose)
6204 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6210 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6212 if (!VEC_empty (constructor_elt, constructor_elements)
6213 && (VEC_last (constructor_elt, constructor_elements)->index
6215 return VEC_last (constructor_elt, constructor_elements)->value;
6220 /* "Output" the next constructor element.
6221 At top level, really output it to assembler code now.
6222 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6223 TYPE is the data type that the containing data type wants here.
6224 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6225 If VALUE is a string constant, STRICT_STRING is true if it is
6226 unparenthesized or we should not warn here for it being parenthesized.
6227 For other types of VALUE, STRICT_STRING is not used.
6229 PENDING if non-nil means output pending elements that belong
6230 right after this element. (PENDING is normally 1;
6231 it is 0 while outputting pending elements, to avoid recursion.) */
6234 output_init_element (tree value, bool strict_string, tree type, tree field,
6237 constructor_elt *celt;
6239 if (type == error_mark_node || value == error_mark_node)
6241 constructor_erroneous = 1;
6244 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6245 && (TREE_CODE (value) == STRING_CST
6246 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6247 && !(TREE_CODE (value) == STRING_CST
6248 && TREE_CODE (type) == ARRAY_TYPE
6249 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6250 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6251 TYPE_MAIN_VARIANT (type)))
6252 value = array_to_pointer_conversion (value);
6254 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6255 && require_constant_value && !flag_isoc99 && pending)
6257 /* As an extension, allow initializing objects with static storage
6258 duration with compound literals (which are then treated just as
6259 the brace enclosed list they contain). */
6260 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6261 value = DECL_INITIAL (decl);
6264 if (value == error_mark_node)
6265 constructor_erroneous = 1;
6266 else if (!TREE_CONSTANT (value))
6267 constructor_constant = 0;
6268 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6269 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6270 || TREE_CODE (constructor_type) == UNION_TYPE)
6271 && DECL_C_BIT_FIELD (field)
6272 && TREE_CODE (value) != INTEGER_CST))
6273 constructor_simple = 0;
6275 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6277 if (require_constant_value)
6279 error_init ("initializer element is not constant");
6280 value = error_mark_node;
6282 else if (require_constant_elements)
6283 pedwarn ("initializer element is not computable at load time");
6286 /* If this field is empty (and not at the end of structure),
6287 don't do anything other than checking the initializer. */
6289 && (TREE_TYPE (field) == error_mark_node
6290 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6291 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6292 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6293 || TREE_CHAIN (field)))))
6296 value = digest_init (type, value, strict_string, require_constant_value);
6297 if (value == error_mark_node)
6299 constructor_erroneous = 1;
6303 /* If this element doesn't come next in sequence,
6304 put it on constructor_pending_elts. */
6305 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6306 && (!constructor_incremental
6307 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6309 if (constructor_incremental
6310 && tree_int_cst_lt (field, constructor_unfilled_index))
6311 set_nonincremental_init ();
6313 add_pending_init (field, value);
6316 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6317 && (!constructor_incremental
6318 || field != constructor_unfilled_fields))
6320 /* We do this for records but not for unions. In a union,
6321 no matter which field is specified, it can be initialized
6322 right away since it starts at the beginning of the union. */
6323 if (constructor_incremental)
6325 if (!constructor_unfilled_fields)
6326 set_nonincremental_init ();
6329 tree bitpos, unfillpos;
6331 bitpos = bit_position (field);
6332 unfillpos = bit_position (constructor_unfilled_fields);
6334 if (tree_int_cst_lt (bitpos, unfillpos))
6335 set_nonincremental_init ();
6339 add_pending_init (field, value);
6342 else if (TREE_CODE (constructor_type) == UNION_TYPE
6343 && !VEC_empty (constructor_elt, constructor_elements))
6345 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6346 constructor_elements)->value))
6347 warning_init (0, "initialized field with side-effects overwritten");
6348 else if (warn_override_init)
6349 warning_init (OPT_Woverride_init, "initialized field overwritten");
6351 /* We can have just one union field set. */
6352 constructor_elements = 0;
6355 /* Otherwise, output this element either to
6356 constructor_elements or to the assembler file. */
6358 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6359 celt->index = field;
6360 celt->value = value;
6362 /* Advance the variable that indicates sequential elements output. */
6363 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6364 constructor_unfilled_index
6365 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6367 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6369 constructor_unfilled_fields
6370 = TREE_CHAIN (constructor_unfilled_fields);
6372 /* Skip any nameless bit fields. */
6373 while (constructor_unfilled_fields != 0
6374 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6375 && DECL_NAME (constructor_unfilled_fields) == 0)
6376 constructor_unfilled_fields =
6377 TREE_CHAIN (constructor_unfilled_fields);
6379 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6380 constructor_unfilled_fields = 0;
6382 /* Now output any pending elements which have become next. */
6384 output_pending_init_elements (0);
6387 /* Output any pending elements which have become next.
6388 As we output elements, constructor_unfilled_{fields,index}
6389 advances, which may cause other elements to become next;
6390 if so, they too are output.
6392 If ALL is 0, we return when there are
6393 no more pending elements to output now.
6395 If ALL is 1, we output space as necessary so that
6396 we can output all the pending elements. */
6399 output_pending_init_elements (int all)
6401 struct init_node *elt = constructor_pending_elts;
6406 /* Look through the whole pending tree.
6407 If we find an element that should be output now,
6408 output it. Otherwise, set NEXT to the element
6409 that comes first among those still pending. */
6414 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6416 if (tree_int_cst_equal (elt->purpose,
6417 constructor_unfilled_index))
6418 output_init_element (elt->value, true,
6419 TREE_TYPE (constructor_type),
6420 constructor_unfilled_index, 0);
6421 else if (tree_int_cst_lt (constructor_unfilled_index,
6424 /* Advance to the next smaller node. */
6429 /* We have reached the smallest node bigger than the
6430 current unfilled index. Fill the space first. */
6431 next = elt->purpose;
6437 /* Advance to the next bigger node. */
6442 /* We have reached the biggest node in a subtree. Find
6443 the parent of it, which is the next bigger node. */
6444 while (elt->parent && elt->parent->right == elt)
6447 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6450 next = elt->purpose;
6456 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6457 || TREE_CODE (constructor_type) == UNION_TYPE)
6459 tree ctor_unfilled_bitpos, elt_bitpos;
6461 /* If the current record is complete we are done. */
6462 if (constructor_unfilled_fields == 0)
6465 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6466 elt_bitpos = bit_position (elt->purpose);
6467 /* We can't compare fields here because there might be empty
6468 fields in between. */
6469 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6471 constructor_unfilled_fields = elt->purpose;
6472 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6475 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6477 /* Advance to the next smaller node. */
6482 /* We have reached the smallest node bigger than the
6483 current unfilled field. Fill the space first. */
6484 next = elt->purpose;
6490 /* Advance to the next bigger node. */
6495 /* We have reached the biggest node in a subtree. Find
6496 the parent of it, which is the next bigger node. */
6497 while (elt->parent && elt->parent->right == elt)
6501 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6502 bit_position (elt->purpose))))
6504 next = elt->purpose;
6512 /* Ordinarily return, but not if we want to output all
6513 and there are elements left. */
6514 if (!(all && next != 0))
6517 /* If it's not incremental, just skip over the gap, so that after
6518 jumping to retry we will output the next successive element. */
6519 if (TREE_CODE (constructor_type) == RECORD_TYPE
6520 || TREE_CODE (constructor_type) == UNION_TYPE)
6521 constructor_unfilled_fields = next;
6522 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6523 constructor_unfilled_index = next;
6525 /* ELT now points to the node in the pending tree with the next
6526 initializer to output. */
6530 /* Add one non-braced element to the current constructor level.
6531 This adjusts the current position within the constructor's type.
6532 This may also start or terminate implicit levels
6533 to handle a partly-braced initializer.
6535 Once this has found the correct level for the new element,
6536 it calls output_init_element. */
6539 process_init_element (struct c_expr value)
6541 tree orig_value = value.value;
6542 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6543 bool strict_string = value.original_code == STRING_CST;
6545 designator_depth = 0;
6546 designator_erroneous = 0;
6548 /* Handle superfluous braces around string cst as in
6549 char x[] = {"foo"}; */
6552 && TREE_CODE (constructor_type) == ARRAY_TYPE
6553 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6554 && integer_zerop (constructor_unfilled_index))
6556 if (constructor_stack->replacement_value.value)
6557 error_init ("excess elements in char array initializer");
6558 constructor_stack->replacement_value = value;
6562 if (constructor_stack->replacement_value.value != 0)
6564 error_init ("excess elements in struct initializer");
6568 /* Ignore elements of a brace group if it is entirely superfluous
6569 and has already been diagnosed. */
6570 if (constructor_type == 0)
6573 /* If we've exhausted any levels that didn't have braces,
6575 while (constructor_stack->implicit)
6577 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6578 || TREE_CODE (constructor_type) == UNION_TYPE)
6579 && constructor_fields == 0)
6580 process_init_element (pop_init_level (1));
6581 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6582 && (constructor_max_index == 0
6583 || tree_int_cst_lt (constructor_max_index,
6584 constructor_index)))
6585 process_init_element (pop_init_level (1));
6590 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6591 if (constructor_range_stack)
6593 /* If value is a compound literal and we'll be just using its
6594 content, don't put it into a SAVE_EXPR. */
6595 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6596 || !require_constant_value
6598 value.value = save_expr (value.value);
6603 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6606 enum tree_code fieldcode;
6608 if (constructor_fields == 0)
6610 pedwarn_init ("excess elements in struct initializer");
6614 fieldtype = TREE_TYPE (constructor_fields);
6615 if (fieldtype != error_mark_node)
6616 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6617 fieldcode = TREE_CODE (fieldtype);
6619 /* Error for non-static initialization of a flexible array member. */
6620 if (fieldcode == ARRAY_TYPE
6621 && !require_constant_value
6622 && TYPE_SIZE (fieldtype) == NULL_TREE
6623 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6625 error_init ("non-static initialization of a flexible array member");
6629 /* Accept a string constant to initialize a subarray. */
6630 if (value.value != 0
6631 && fieldcode == ARRAY_TYPE
6632 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6634 value.value = orig_value;
6635 /* Otherwise, if we have come to a subaggregate,
6636 and we don't have an element of its type, push into it. */
6637 else if (value.value != 0
6638 && value.value != error_mark_node
6639 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6640 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6641 || fieldcode == UNION_TYPE))
6643 push_init_level (1);
6649 push_member_name (constructor_fields);
6650 output_init_element (value.value, strict_string,
6651 fieldtype, constructor_fields, 1);
6652 RESTORE_SPELLING_DEPTH (constructor_depth);
6655 /* Do the bookkeeping for an element that was
6656 directly output as a constructor. */
6658 /* For a record, keep track of end position of last field. */
6659 if (DECL_SIZE (constructor_fields))
6660 constructor_bit_index
6661 = size_binop (PLUS_EXPR,
6662 bit_position (constructor_fields),
6663 DECL_SIZE (constructor_fields));
6665 /* If the current field was the first one not yet written out,
6666 it isn't now, so update. */
6667 if (constructor_unfilled_fields == constructor_fields)
6669 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6670 /* Skip any nameless bit fields. */
6671 while (constructor_unfilled_fields != 0
6672 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6673 && DECL_NAME (constructor_unfilled_fields) == 0)
6674 constructor_unfilled_fields =
6675 TREE_CHAIN (constructor_unfilled_fields);
6679 constructor_fields = TREE_CHAIN (constructor_fields);
6680 /* Skip any nameless bit fields at the beginning. */
6681 while (constructor_fields != 0
6682 && DECL_C_BIT_FIELD (constructor_fields)
6683 && DECL_NAME (constructor_fields) == 0)
6684 constructor_fields = TREE_CHAIN (constructor_fields);
6686 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6689 enum tree_code fieldcode;
6691 if (constructor_fields == 0)
6693 pedwarn_init ("excess elements in union initializer");
6697 fieldtype = TREE_TYPE (constructor_fields);
6698 if (fieldtype != error_mark_node)
6699 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6700 fieldcode = TREE_CODE (fieldtype);
6702 /* Warn that traditional C rejects initialization of unions.
6703 We skip the warning if the value is zero. This is done
6704 under the assumption that the zero initializer in user
6705 code appears conditioned on e.g. __STDC__ to avoid
6706 "missing initializer" warnings and relies on default
6707 initialization to zero in the traditional C case.
6708 We also skip the warning if the initializer is designated,
6709 again on the assumption that this must be conditional on
6710 __STDC__ anyway (and we've already complained about the
6711 member-designator already). */
6712 if (!in_system_header && !constructor_designated
6713 && !(value.value && (integer_zerop (value.value)
6714 || real_zerop (value.value))))
6715 warning (OPT_Wtraditional, "traditional C rejects initialization "
6718 /* Accept a string constant to initialize a subarray. */
6719 if (value.value != 0
6720 && fieldcode == ARRAY_TYPE
6721 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6723 value.value = orig_value;
6724 /* Otherwise, if we have come to a subaggregate,
6725 and we don't have an element of its type, push into it. */
6726 else if (value.value != 0
6727 && value.value != error_mark_node
6728 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6729 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6730 || fieldcode == UNION_TYPE))
6732 push_init_level (1);
6738 push_member_name (constructor_fields);
6739 output_init_element (value.value, strict_string,
6740 fieldtype, constructor_fields, 1);
6741 RESTORE_SPELLING_DEPTH (constructor_depth);
6744 /* Do the bookkeeping for an element that was
6745 directly output as a constructor. */
6747 constructor_bit_index = DECL_SIZE (constructor_fields);
6748 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6751 constructor_fields = 0;
6753 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6755 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6756 enum tree_code eltcode = TREE_CODE (elttype);
6758 /* Accept a string constant to initialize a subarray. */
6759 if (value.value != 0
6760 && eltcode == ARRAY_TYPE
6761 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6763 value.value = orig_value;
6764 /* Otherwise, if we have come to a subaggregate,
6765 and we don't have an element of its type, push into it. */
6766 else if (value.value != 0
6767 && value.value != error_mark_node
6768 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6769 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6770 || eltcode == UNION_TYPE))
6772 push_init_level (1);
6776 if (constructor_max_index != 0
6777 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6778 || integer_all_onesp (constructor_max_index)))
6780 pedwarn_init ("excess elements in array initializer");
6784 /* Now output the actual element. */
6787 push_array_bounds (tree_low_cst (constructor_index, 1));
6788 output_init_element (value.value, strict_string,
6789 elttype, constructor_index, 1);
6790 RESTORE_SPELLING_DEPTH (constructor_depth);
6794 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6797 /* If we are doing the bookkeeping for an element that was
6798 directly output as a constructor, we must update
6799 constructor_unfilled_index. */
6800 constructor_unfilled_index = constructor_index;
6802 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6804 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6806 /* Do a basic check of initializer size. Note that vectors
6807 always have a fixed size derived from their type. */
6808 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6810 pedwarn_init ("excess elements in vector initializer");
6814 /* Now output the actual element. */
6816 output_init_element (value.value, strict_string,
6817 elttype, constructor_index, 1);
6820 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6823 /* If we are doing the bookkeeping for an element that was
6824 directly output as a constructor, we must update
6825 constructor_unfilled_index. */
6826 constructor_unfilled_index = constructor_index;
6829 /* Handle the sole element allowed in a braced initializer
6830 for a scalar variable. */
6831 else if (constructor_type != error_mark_node
6832 && constructor_fields == 0)
6834 pedwarn_init ("excess elements in scalar initializer");
6840 output_init_element (value.value, strict_string,
6841 constructor_type, NULL_TREE, 1);
6842 constructor_fields = 0;
6845 /* Handle range initializers either at this level or anywhere higher
6846 in the designator stack. */
6847 if (constructor_range_stack)
6849 struct constructor_range_stack *p, *range_stack;
6852 range_stack = constructor_range_stack;
6853 constructor_range_stack = 0;
6854 while (constructor_stack != range_stack->stack)
6856 gcc_assert (constructor_stack->implicit);
6857 process_init_element (pop_init_level (1));
6859 for (p = range_stack;
6860 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6863 gcc_assert (constructor_stack->implicit);
6864 process_init_element (pop_init_level (1));
6867 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6868 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6873 constructor_index = p->index;
6874 constructor_fields = p->fields;
6875 if (finish && p->range_end && p->index == p->range_start)
6883 push_init_level (2);
6884 p->stack = constructor_stack;
6885 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6886 p->index = p->range_start;
6890 constructor_range_stack = range_stack;
6897 constructor_range_stack = 0;
6900 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6901 (guaranteed to be 'volatile' or null) and ARGS (represented using
6902 an ASM_EXPR node). */
6904 build_asm_stmt (tree cv_qualifier, tree args)
6906 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6907 ASM_VOLATILE_P (args) = 1;
6908 return add_stmt (args);
6911 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6912 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6913 SIMPLE indicates whether there was anything at all after the
6914 string in the asm expression -- asm("blah") and asm("blah" : )
6915 are subtly different. We use a ASM_EXPR node to represent this. */
6917 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6923 const char *constraint;
6924 const char **oconstraints;
6925 bool allows_mem, allows_reg, is_inout;
6926 int ninputs, noutputs;
6928 ninputs = list_length (inputs);
6929 noutputs = list_length (outputs);
6930 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6932 string = resolve_asm_operand_names (string, outputs, inputs);
6934 /* Remove output conversions that change the type but not the mode. */
6935 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6937 tree output = TREE_VALUE (tail);
6939 /* ??? Really, this should not be here. Users should be using a
6940 proper lvalue, dammit. But there's a long history of using casts
6941 in the output operands. In cases like longlong.h, this becomes a
6942 primitive form of typechecking -- if the cast can be removed, then
6943 the output operand had a type of the proper width; otherwise we'll
6944 get an error. Gross, but ... */
6945 STRIP_NOPS (output);
6947 if (!lvalue_or_else (output, lv_asm))
6948 output = error_mark_node;
6950 if (output != error_mark_node
6951 && (TREE_READONLY (output)
6952 || TYPE_READONLY (TREE_TYPE (output))
6953 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6954 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6955 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6956 readonly_error (output, lv_asm);
6958 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6959 oconstraints[i] = constraint;
6961 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6962 &allows_mem, &allows_reg, &is_inout))
6964 /* If the operand is going to end up in memory,
6965 mark it addressable. */
6966 if (!allows_reg && !c_mark_addressable (output))
6967 output = error_mark_node;
6970 output = error_mark_node;
6972 TREE_VALUE (tail) = output;
6975 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6979 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6980 input = TREE_VALUE (tail);
6982 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6983 oconstraints, &allows_mem, &allows_reg))
6985 /* If the operand is going to end up in memory,
6986 mark it addressable. */
6987 if (!allows_reg && allows_mem)
6989 /* Strip the nops as we allow this case. FIXME, this really
6990 should be rejected or made deprecated. */
6992 if (!c_mark_addressable (input))
6993 input = error_mark_node;
6997 input = error_mark_node;
6999 TREE_VALUE (tail) = input;
7002 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
7004 /* asm statements without outputs, including simple ones, are treated
7006 ASM_INPUT_P (args) = simple;
7007 ASM_VOLATILE_P (args) = (noutputs == 0);
7012 /* Generate a goto statement to LABEL. */
7015 c_finish_goto_label (tree label)
7017 tree decl = lookup_label (label);
7021 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
7023 error ("jump into statement expression");
7027 if (C_DECL_UNJUMPABLE_VM (decl))
7029 error ("jump into scope of identifier with variably modified type");
7033 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
7035 /* No jump from outside this statement expression context, so
7036 record that there is a jump from within this context. */
7037 struct c_label_list *nlist;
7038 nlist = XOBNEW (&parser_obstack, struct c_label_list);
7039 nlist->next = label_context_stack_se->labels_used;
7040 nlist->label = decl;
7041 label_context_stack_se->labels_used = nlist;
7044 if (!C_DECL_UNDEFINABLE_VM (decl))
7046 /* No jump from outside this context context of identifiers with
7047 variably modified type, so record that there is a jump from
7048 within this context. */
7049 struct c_label_list *nlist;
7050 nlist = XOBNEW (&parser_obstack, struct c_label_list);
7051 nlist->next = label_context_stack_vm->labels_used;
7052 nlist->label = decl;
7053 label_context_stack_vm->labels_used = nlist;
7056 TREE_USED (decl) = 1;
7057 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
7060 /* Generate a computed goto statement to EXPR. */
7063 c_finish_goto_ptr (tree expr)
7066 pedwarn ("ISO C forbids %<goto *expr;%>");
7067 expr = convert (ptr_type_node, expr);
7068 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
7071 /* Generate a C `return' statement. RETVAL is the expression for what
7072 to return, or a null pointer for `return;' with no value. */
7075 c_finish_return (tree retval)
7077 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
7078 bool no_warning = false;
7080 if (TREE_THIS_VOLATILE (current_function_decl))
7081 warning (0, "function declared %<noreturn%> has a %<return%> statement");
7085 current_function_returns_null = 1;
7086 if ((warn_return_type || flag_isoc99)
7087 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
7089 pedwarn_c99 ("%<return%> with no value, in "
7090 "function returning non-void");
7094 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
7096 current_function_returns_null = 1;
7097 if (TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
7098 pedwarn ("%<return%> with a value, in function returning void");
7100 pedwarn ("ISO C forbids %<return%> with expression, in function returning void");
7104 tree t = convert_for_assignment (valtype, retval, ic_return,
7105 NULL_TREE, NULL_TREE, 0);
7106 tree res = DECL_RESULT (current_function_decl);
7109 current_function_returns_value = 1;
7110 if (t == error_mark_node)
7113 inner = t = convert (TREE_TYPE (res), t);
7115 /* Strip any conversions, additions, and subtractions, and see if
7116 we are returning the address of a local variable. Warn if so. */
7119 switch (TREE_CODE (inner))
7121 CASE_CONVERT: case NON_LVALUE_EXPR:
7123 inner = TREE_OPERAND (inner, 0);
7127 /* If the second operand of the MINUS_EXPR has a pointer
7128 type (or is converted from it), this may be valid, so
7129 don't give a warning. */
7131 tree op1 = TREE_OPERAND (inner, 1);
7133 while (!POINTER_TYPE_P (TREE_TYPE (op1))
7134 && (CONVERT_EXPR_P (op1)
7135 || TREE_CODE (op1) == NON_LVALUE_EXPR))
7136 op1 = TREE_OPERAND (op1, 0);
7138 if (POINTER_TYPE_P (TREE_TYPE (op1)))
7141 inner = TREE_OPERAND (inner, 0);
7146 inner = TREE_OPERAND (inner, 0);
7148 while (REFERENCE_CLASS_P (inner)
7149 && TREE_CODE (inner) != INDIRECT_REF)
7150 inner = TREE_OPERAND (inner, 0);
7153 && !DECL_EXTERNAL (inner)
7154 && !TREE_STATIC (inner)
7155 && DECL_CONTEXT (inner) == current_function_decl)
7156 warning (0, "function returns address of local variable");
7166 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7169 ret_stmt = build_stmt (RETURN_EXPR, retval);
7170 TREE_NO_WARNING (ret_stmt) |= no_warning;
7171 return add_stmt (ret_stmt);
7175 /* The SWITCH_EXPR being built. */
7178 /* The original type of the testing expression, i.e. before the
7179 default conversion is applied. */
7182 /* A splay-tree mapping the low element of a case range to the high
7183 element, or NULL_TREE if there is no high element. Used to
7184 determine whether or not a new case label duplicates an old case
7185 label. We need a tree, rather than simply a hash table, because
7186 of the GNU case range extension. */
7189 /* Number of nested statement expressions within this switch
7190 statement; if nonzero, case and default labels may not
7192 unsigned int blocked_stmt_expr;
7194 /* Scope of outermost declarations of identifiers with variably
7195 modified type within this switch statement; if nonzero, case and
7196 default labels may not appear. */
7197 unsigned int blocked_vm;
7199 /* The next node on the stack. */
7200 struct c_switch *next;
7203 /* A stack of the currently active switch statements. The innermost
7204 switch statement is on the top of the stack. There is no need to
7205 mark the stack for garbage collection because it is only active
7206 during the processing of the body of a function, and we never
7207 collect at that point. */
7209 struct c_switch *c_switch_stack;
7211 /* Start a C switch statement, testing expression EXP. Return the new
7215 c_start_case (tree exp)
7217 tree orig_type = error_mark_node;
7218 struct c_switch *cs;
7220 if (exp != error_mark_node)
7222 orig_type = TREE_TYPE (exp);
7224 if (!INTEGRAL_TYPE_P (orig_type))
7226 if (orig_type != error_mark_node)
7228 error ("switch quantity not an integer");
7229 orig_type = error_mark_node;
7231 exp = integer_zero_node;
7235 tree type = TYPE_MAIN_VARIANT (orig_type);
7237 if (!in_system_header
7238 && (type == long_integer_type_node
7239 || type == long_unsigned_type_node))
7240 warning (OPT_Wtraditional, "%<long%> switch expression not "
7241 "converted to %<int%> in ISO C");
7243 exp = default_conversion (exp);
7247 /* Add this new SWITCH_EXPR to the stack. */
7248 cs = XNEW (struct c_switch);
7249 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7250 cs->orig_type = orig_type;
7251 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7252 cs->blocked_stmt_expr = 0;
7254 cs->next = c_switch_stack;
7255 c_switch_stack = cs;
7257 return add_stmt (cs->switch_expr);
7260 /* Process a case label. */
7263 do_case (tree low_value, tree high_value)
7265 tree label = NULL_TREE;
7267 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7268 && !c_switch_stack->blocked_vm)
7270 label = c_add_case_label (c_switch_stack->cases,
7271 SWITCH_COND (c_switch_stack->switch_expr),
7272 c_switch_stack->orig_type,
7273 low_value, high_value);
7274 if (label == error_mark_node)
7277 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7280 error ("case label in statement expression not containing "
7281 "enclosing switch statement");
7283 error ("%<default%> label in statement expression not containing "
7284 "enclosing switch statement");
7286 else if (c_switch_stack && c_switch_stack->blocked_vm)
7289 error ("case label in scope of identifier with variably modified "
7290 "type not containing enclosing switch statement");
7292 error ("%<default%> label in scope of identifier with variably "
7293 "modified type not containing enclosing switch statement");
7296 error ("case label not within a switch statement");
7298 error ("%<default%> label not within a switch statement");
7303 /* Finish the switch statement. */
7306 c_finish_case (tree body)
7308 struct c_switch *cs = c_switch_stack;
7309 location_t switch_location;
7311 SWITCH_BODY (cs->switch_expr) = body;
7313 /* We must not be within a statement expression nested in the switch
7314 at this point; we might, however, be within the scope of an
7315 identifier with variably modified type nested in the switch. */
7316 gcc_assert (!cs->blocked_stmt_expr);
7318 /* Emit warnings as needed. */
7319 if (EXPR_HAS_LOCATION (cs->switch_expr))
7320 switch_location = EXPR_LOCATION (cs->switch_expr);
7322 switch_location = input_location;
7323 c_do_switch_warnings (cs->cases, switch_location,
7324 TREE_TYPE (cs->switch_expr),
7325 SWITCH_COND (cs->switch_expr));
7327 /* Pop the stack. */
7328 c_switch_stack = cs->next;
7329 splay_tree_delete (cs->cases);
7333 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7334 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7335 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7336 statement, and was not surrounded with parenthesis. */
7339 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7340 tree else_block, bool nested_if)
7344 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7345 if (warn_parentheses && nested_if && else_block == NULL)
7347 tree inner_if = then_block;
7349 /* We know from the grammar productions that there is an IF nested
7350 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7351 it might not be exactly THEN_BLOCK, but should be the last
7352 non-container statement within. */
7354 switch (TREE_CODE (inner_if))
7359 inner_if = BIND_EXPR_BODY (inner_if);
7361 case STATEMENT_LIST:
7362 inner_if = expr_last (then_block);
7364 case TRY_FINALLY_EXPR:
7365 case TRY_CATCH_EXPR:
7366 inner_if = TREE_OPERAND (inner_if, 0);
7373 if (COND_EXPR_ELSE (inner_if))
7374 warning (OPT_Wparentheses,
7375 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7379 empty_if_body_warning (then_block, else_block);
7381 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7382 SET_EXPR_LOCATION (stmt, if_locus);
7386 /* Emit a general-purpose loop construct. START_LOCUS is the location of
7387 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
7388 is false for DO loops. INCR is the FOR increment expression. BODY is
7389 the statement controlled by the loop. BLAB is the break label. CLAB is
7390 the continue label. Everything is allowed to be NULL. */
7393 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7394 tree blab, tree clab, bool cond_is_first)
7396 tree entry = NULL, exit = NULL, t;
7398 /* If the condition is zero don't generate a loop construct. */
7399 if (cond && integer_zerop (cond))
7403 t = build_and_jump (&blab);
7404 SET_EXPR_LOCATION (t, start_locus);
7410 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7412 /* If we have an exit condition, then we build an IF with gotos either
7413 out of the loop, or to the top of it. If there's no exit condition,
7414 then we just build a jump back to the top. */
7415 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7417 if (cond && !integer_nonzerop (cond))
7419 /* Canonicalize the loop condition to the end. This means
7420 generating a branch to the loop condition. Reuse the
7421 continue label, if possible. */
7426 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7427 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7430 t = build1 (GOTO_EXPR, void_type_node, clab);
7431 SET_EXPR_LOCATION (t, start_locus);
7435 t = build_and_jump (&blab);
7436 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7438 SET_EXPR_LOCATION (exit, start_locus);
7440 SET_EXPR_LOCATION (exit, input_location);
7449 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7457 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7461 c_finish_bc_stmt (tree *label_p, bool is_break)
7464 tree label = *label_p;
7466 /* In switch statements break is sometimes stylistically used after
7467 a return statement. This can lead to spurious warnings about
7468 control reaching the end of a non-void function when it is
7469 inlined. Note that we are calling block_may_fallthru with
7470 language specific tree nodes; this works because
7471 block_may_fallthru returns true when given something it does not
7473 skip = !block_may_fallthru (cur_stmt_list);
7478 *label_p = label = create_artificial_label ();
7480 else if (TREE_CODE (label) == LABEL_DECL)
7482 else switch (TREE_INT_CST_LOW (label))
7486 error ("break statement not within loop or switch");
7488 error ("continue statement not within a loop");
7492 gcc_assert (is_break);
7493 error ("break statement used with OpenMP for loop");
7504 add_stmt (build_predict_expr (PRED_CONTINUE, NOT_TAKEN));
7506 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7509 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7512 emit_side_effect_warnings (tree expr)
7514 if (expr == error_mark_node)
7516 else if (!TREE_SIDE_EFFECTS (expr))
7518 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7519 warning (OPT_Wunused_value, "%Hstatement with no effect",
7520 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7523 warn_if_unused_value (expr, input_location);
7526 /* Process an expression as if it were a complete statement. Emit
7527 diagnostics, but do not call ADD_STMT. */
7530 c_process_expr_stmt (tree expr)
7535 if (warn_sequence_point)
7536 verify_sequence_points (expr);
7538 if (TREE_TYPE (expr) != error_mark_node
7539 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7540 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7541 error ("expression statement has incomplete type");
7543 /* If we're not processing a statement expression, warn about unused values.
7544 Warnings for statement expressions will be emitted later, once we figure
7545 out which is the result. */
7546 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7547 && warn_unused_value)
7548 emit_side_effect_warnings (expr);
7550 /* If the expression is not of a type to which we cannot assign a line
7551 number, wrap the thing in a no-op NOP_EXPR. */
7552 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7553 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7555 if (CAN_HAVE_LOCATION_P (expr))
7556 SET_EXPR_LOCATION (expr, input_location);
7561 /* Emit an expression as a statement. */
7564 c_finish_expr_stmt (tree expr)
7567 return add_stmt (c_process_expr_stmt (expr));
7572 /* Do the opposite and emit a statement as an expression. To begin,
7573 create a new binding level and return it. */
7576 c_begin_stmt_expr (void)
7579 struct c_label_context_se *nstack;
7580 struct c_label_list *glist;
7582 /* We must force a BLOCK for this level so that, if it is not expanded
7583 later, there is a way to turn off the entire subtree of blocks that
7584 are contained in it. */
7586 ret = c_begin_compound_stmt (true);
7589 c_switch_stack->blocked_stmt_expr++;
7590 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7592 for (glist = label_context_stack_se->labels_used;
7594 glist = glist->next)
7596 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7598 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7599 nstack->labels_def = NULL;
7600 nstack->labels_used = NULL;
7601 nstack->next = label_context_stack_se;
7602 label_context_stack_se = nstack;
7604 /* Mark the current statement list as belonging to a statement list. */
7605 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7611 c_finish_stmt_expr (tree body)
7613 tree last, type, tmp, val;
7615 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7617 body = c_end_compound_stmt (body, true);
7620 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7621 c_switch_stack->blocked_stmt_expr--;
7623 /* It is no longer possible to jump to labels defined within this
7624 statement expression. */
7625 for (dlist = label_context_stack_se->labels_def;
7627 dlist = dlist->next)
7629 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7631 /* It is again possible to define labels with a goto just outside
7632 this statement expression. */
7633 for (glist = label_context_stack_se->next->labels_used;
7635 glist = glist->next)
7637 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7640 if (glist_prev != NULL)
7641 glist_prev->next = label_context_stack_se->labels_used;
7643 label_context_stack_se->next->labels_used
7644 = label_context_stack_se->labels_used;
7645 label_context_stack_se = label_context_stack_se->next;
7647 /* Locate the last statement in BODY. See c_end_compound_stmt
7648 about always returning a BIND_EXPR. */
7649 last_p = &BIND_EXPR_BODY (body);
7650 last = BIND_EXPR_BODY (body);
7653 if (TREE_CODE (last) == STATEMENT_LIST)
7655 tree_stmt_iterator i;
7657 /* This can happen with degenerate cases like ({ }). No value. */
7658 if (!TREE_SIDE_EFFECTS (last))
7661 /* If we're supposed to generate side effects warnings, process
7662 all of the statements except the last. */
7663 if (warn_unused_value)
7665 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7666 emit_side_effect_warnings (tsi_stmt (i));
7669 i = tsi_last (last);
7670 last_p = tsi_stmt_ptr (i);
7674 /* If the end of the list is exception related, then the list was split
7675 by a call to push_cleanup. Continue searching. */
7676 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7677 || TREE_CODE (last) == TRY_CATCH_EXPR)
7679 last_p = &TREE_OPERAND (last, 0);
7681 goto continue_searching;
7684 /* In the case that the BIND_EXPR is not necessary, return the
7685 expression out from inside it. */
7686 if (last == error_mark_node
7687 || (last == BIND_EXPR_BODY (body)
7688 && BIND_EXPR_VARS (body) == NULL))
7690 /* Do not warn if the return value of a statement expression is
7692 if (CAN_HAVE_LOCATION_P (last))
7693 TREE_NO_WARNING (last) = 1;
7697 /* Extract the type of said expression. */
7698 type = TREE_TYPE (last);
7700 /* If we're not returning a value at all, then the BIND_EXPR that
7701 we already have is a fine expression to return. */
7702 if (!type || VOID_TYPE_P (type))
7705 /* Now that we've located the expression containing the value, it seems
7706 silly to make voidify_wrapper_expr repeat the process. Create a
7707 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7708 tmp = create_tmp_var_raw (type, NULL);
7710 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7711 tree_expr_nonnegative_p giving up immediately. */
7713 if (TREE_CODE (val) == NOP_EXPR
7714 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7715 val = TREE_OPERAND (val, 0);
7717 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7718 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7720 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7723 /* Begin the scope of an identifier of variably modified type, scope
7724 number SCOPE. Jumping from outside this scope to inside it is not
7728 c_begin_vm_scope (unsigned int scope)
7730 struct c_label_context_vm *nstack;
7731 struct c_label_list *glist;
7733 gcc_assert (scope > 0);
7735 /* At file_scope, we don't have to do any processing. */
7736 if (label_context_stack_vm == NULL)
7739 if (c_switch_stack && !c_switch_stack->blocked_vm)
7740 c_switch_stack->blocked_vm = scope;
7741 for (glist = label_context_stack_vm->labels_used;
7743 glist = glist->next)
7745 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7747 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7748 nstack->labels_def = NULL;
7749 nstack->labels_used = NULL;
7750 nstack->scope = scope;
7751 nstack->next = label_context_stack_vm;
7752 label_context_stack_vm = nstack;
7755 /* End a scope which may contain identifiers of variably modified
7756 type, scope number SCOPE. */
7759 c_end_vm_scope (unsigned int scope)
7761 if (label_context_stack_vm == NULL)
7763 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7764 c_switch_stack->blocked_vm = 0;
7765 /* We may have a number of nested scopes of identifiers with
7766 variably modified type, all at this depth. Pop each in turn. */
7767 while (label_context_stack_vm->scope == scope)
7769 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7771 /* It is no longer possible to jump to labels defined within this
7773 for (dlist = label_context_stack_vm->labels_def;
7775 dlist = dlist->next)
7777 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7779 /* It is again possible to define labels with a goto just outside
7781 for (glist = label_context_stack_vm->next->labels_used;
7783 glist = glist->next)
7785 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7788 if (glist_prev != NULL)
7789 glist_prev->next = label_context_stack_vm->labels_used;
7791 label_context_stack_vm->next->labels_used
7792 = label_context_stack_vm->labels_used;
7793 label_context_stack_vm = label_context_stack_vm->next;
7797 /* Begin and end compound statements. This is as simple as pushing
7798 and popping new statement lists from the tree. */
7801 c_begin_compound_stmt (bool do_scope)
7803 tree stmt = push_stmt_list ();
7810 c_end_compound_stmt (tree stmt, bool do_scope)
7816 if (c_dialect_objc ())
7817 objc_clear_super_receiver ();
7818 block = pop_scope ();
7821 stmt = pop_stmt_list (stmt);
7822 stmt = c_build_bind_expr (block, stmt);
7824 /* If this compound statement is nested immediately inside a statement
7825 expression, then force a BIND_EXPR to be created. Otherwise we'll
7826 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7827 STATEMENT_LISTs merge, and thus we can lose track of what statement
7830 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7831 && TREE_CODE (stmt) != BIND_EXPR)
7833 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7834 TREE_SIDE_EFFECTS (stmt) = 1;
7840 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7841 when the current scope is exited. EH_ONLY is true when this is not
7842 meant to apply to normal control flow transfer. */
7845 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7847 enum tree_code code;
7851 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7852 stmt = build_stmt (code, NULL, cleanup);
7854 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7855 list = push_stmt_list ();
7856 TREE_OPERAND (stmt, 0) = list;
7857 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7860 /* Build a binary-operation expression without default conversions.
7861 CODE is the kind of expression to build.
7862 This function differs from `build' in several ways:
7863 the data type of the result is computed and recorded in it,
7864 warnings are generated if arg data types are invalid,
7865 special handling for addition and subtraction of pointers is known,
7866 and some optimization is done (operations on narrow ints
7867 are done in the narrower type when that gives the same result).
7868 Constant folding is also done before the result is returned.
7870 Note that the operands will never have enumeral types, or function
7871 or array types, because either they will have the default conversions
7872 performed or they have both just been converted to some other type in which
7873 the arithmetic is to be done. */
7876 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7880 enum tree_code code0, code1;
7882 const char *invalid_op_diag;
7884 /* Expression code to give to the expression when it is built.
7885 Normally this is CODE, which is what the caller asked for,
7886 but in some special cases we change it. */
7887 enum tree_code resultcode = code;
7889 /* Data type in which the computation is to be performed.
7890 In the simplest cases this is the common type of the arguments. */
7891 tree result_type = NULL;
7893 /* Nonzero means operands have already been type-converted
7894 in whatever way is necessary.
7895 Zero means they need to be converted to RESULT_TYPE. */
7898 /* Nonzero means create the expression with this type, rather than
7900 tree build_type = 0;
7902 /* Nonzero means after finally constructing the expression
7903 convert it to this type. */
7904 tree final_type = 0;
7906 /* Nonzero if this is an operation like MIN or MAX which can
7907 safely be computed in short if both args are promoted shorts.
7908 Also implies COMMON.
7909 -1 indicates a bitwise operation; this makes a difference
7910 in the exact conditions for when it is safe to do the operation
7911 in a narrower mode. */
7914 /* Nonzero if this is a comparison operation;
7915 if both args are promoted shorts, compare the original shorts.
7916 Also implies COMMON. */
7917 int short_compare = 0;
7919 /* Nonzero if this is a right-shift operation, which can be computed on the
7920 original short and then promoted if the operand is a promoted short. */
7921 int short_shift = 0;
7923 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7926 /* True means types are compatible as far as ObjC is concerned. */
7931 op0 = default_conversion (orig_op0);
7932 op1 = default_conversion (orig_op1);
7940 type0 = TREE_TYPE (op0);
7941 type1 = TREE_TYPE (op1);
7943 /* The expression codes of the data types of the arguments tell us
7944 whether the arguments are integers, floating, pointers, etc. */
7945 code0 = TREE_CODE (type0);
7946 code1 = TREE_CODE (type1);
7948 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7949 STRIP_TYPE_NOPS (op0);
7950 STRIP_TYPE_NOPS (op1);
7952 /* If an error was already reported for one of the arguments,
7953 avoid reporting another error. */
7955 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7956 return error_mark_node;
7958 if ((invalid_op_diag
7959 = targetm.invalid_binary_op (code, type0, type1)))
7961 error (invalid_op_diag);
7962 return error_mark_node;
7965 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7970 /* Handle the pointer + int case. */
7971 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7972 return pointer_int_sum (PLUS_EXPR, op0, op1);
7973 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7974 return pointer_int_sum (PLUS_EXPR, op1, op0);
7980 /* Subtraction of two similar pointers.
7981 We must subtract them as integers, then divide by object size. */
7982 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7983 && comp_target_types (type0, type1))
7984 return pointer_diff (op0, op1);
7985 /* Handle pointer minus int. Just like pointer plus int. */
7986 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7987 return pointer_int_sum (MINUS_EXPR, op0, op1);
7996 case TRUNC_DIV_EXPR:
7998 case FLOOR_DIV_EXPR:
7999 case ROUND_DIV_EXPR:
8000 case EXACT_DIV_EXPR:
8001 warn_for_div_by_zero (op1);
8003 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8004 || code0 == FIXED_POINT_TYPE
8005 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
8006 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8007 || code1 == FIXED_POINT_TYPE
8008 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
8010 enum tree_code tcode0 = code0, tcode1 = code1;
8012 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
8013 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
8014 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
8015 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
8017 if (!((tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)
8018 || (tcode0 == FIXED_POINT_TYPE && tcode1 == FIXED_POINT_TYPE)))
8019 resultcode = RDIV_EXPR;
8021 /* Although it would be tempting to shorten always here, that
8022 loses on some targets, since the modulo instruction is
8023 undefined if the quotient can't be represented in the
8024 computation mode. We shorten only if unsigned or if
8025 dividing by something we know != -1. */
8026 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
8027 || (TREE_CODE (op1) == INTEGER_CST
8028 && !integer_all_onesp (op1)));
8036 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
8038 /* Allow vector types which are not floating point types. */
8039 else if (code0 == VECTOR_TYPE
8040 && code1 == VECTOR_TYPE
8041 && !VECTOR_FLOAT_TYPE_P (type0)
8042 && !VECTOR_FLOAT_TYPE_P (type1))
8046 case TRUNC_MOD_EXPR:
8047 case FLOOR_MOD_EXPR:
8048 warn_for_div_by_zero (op1);
8050 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
8052 /* Although it would be tempting to shorten always here, that loses
8053 on some targets, since the modulo instruction is undefined if the
8054 quotient can't be represented in the computation mode. We shorten
8055 only if unsigned or if dividing by something we know != -1. */
8056 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
8057 || (TREE_CODE (op1) == INTEGER_CST
8058 && !integer_all_onesp (op1)));
8063 case TRUTH_ANDIF_EXPR:
8064 case TRUTH_ORIF_EXPR:
8065 case TRUTH_AND_EXPR:
8067 case TRUTH_XOR_EXPR:
8068 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
8069 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8070 || code0 == FIXED_POINT_TYPE)
8071 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
8072 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8073 || code1 == FIXED_POINT_TYPE))
8075 /* Result of these operations is always an int,
8076 but that does not mean the operands should be
8077 converted to ints! */
8078 result_type = integer_type_node;
8079 op0 = c_common_truthvalue_conversion (op0);
8080 op1 = c_common_truthvalue_conversion (op1);
8085 /* Shift operations: result has same type as first operand;
8086 always convert second operand to int.
8087 Also set SHORT_SHIFT if shifting rightward. */
8090 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
8091 && code1 == INTEGER_TYPE)
8093 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
8095 if (tree_int_cst_sgn (op1) < 0)
8096 warning (0, "right shift count is negative");
8099 if (!integer_zerop (op1))
8102 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
8103 warning (0, "right shift count >= width of type");
8107 /* Use the type of the value to be shifted. */
8108 result_type = type0;
8109 /* Convert the shift-count to an integer, regardless of size
8110 of value being shifted. */
8111 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
8112 op1 = convert (integer_type_node, op1);
8113 /* Avoid converting op1 to result_type later. */
8119 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
8120 && code1 == INTEGER_TYPE)
8122 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
8124 if (tree_int_cst_sgn (op1) < 0)
8125 warning (0, "left shift count is negative");
8127 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
8128 warning (0, "left shift count >= width of type");
8131 /* Use the type of the value to be shifted. */
8132 result_type = type0;
8133 /* Convert the shift-count to an integer, regardless of size
8134 of value being shifted. */
8135 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
8136 op1 = convert (integer_type_node, op1);
8137 /* Avoid converting op1 to result_type later. */
8144 if (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1))
8145 warning (OPT_Wfloat_equal,
8146 "comparing floating point with == or != is unsafe");
8147 /* Result of comparison is always int,
8148 but don't convert the args to int! */
8149 build_type = integer_type_node;
8150 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8151 || code0 == FIXED_POINT_TYPE || code0 == COMPLEX_TYPE)
8152 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8153 || code1 == FIXED_POINT_TYPE || code1 == COMPLEX_TYPE))
8155 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8157 tree tt0 = TREE_TYPE (type0);
8158 tree tt1 = TREE_TYPE (type1);
8159 /* Anything compares with void *. void * compares with anything.
8160 Otherwise, the targets must be compatible
8161 and both must be object or both incomplete. */
8162 if (comp_target_types (type0, type1))
8163 result_type = common_pointer_type (type0, type1);
8164 else if (VOID_TYPE_P (tt0))
8166 /* op0 != orig_op0 detects the case of something
8167 whose value is 0 but which isn't a valid null ptr const. */
8168 if (pedantic && !null_pointer_constant_p (orig_op0)
8169 && TREE_CODE (tt1) == FUNCTION_TYPE)
8170 pedwarn ("ISO C forbids comparison of %<void *%>"
8171 " with function pointer");
8173 else if (VOID_TYPE_P (tt1))
8175 if (pedantic && !null_pointer_constant_p (orig_op1)
8176 && TREE_CODE (tt0) == FUNCTION_TYPE)
8177 pedwarn ("ISO C forbids comparison of %<void *%>"
8178 " with function pointer");
8181 /* Avoid warning about the volatile ObjC EH puts on decls. */
8183 pedwarn ("comparison of distinct pointer types lacks a cast");
8185 if (result_type == NULL_TREE)
8186 result_type = ptr_type_node;
8188 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8190 if (TREE_CODE (op0) == ADDR_EXPR
8191 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
8192 warning (OPT_Waddress, "the address of %qD will never be NULL",
8193 TREE_OPERAND (op0, 0));
8194 result_type = type0;
8196 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8198 if (TREE_CODE (op1) == ADDR_EXPR
8199 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
8200 warning (OPT_Waddress, "the address of %qD will never be NULL",
8201 TREE_OPERAND (op1, 0));
8202 result_type = type1;
8204 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8206 result_type = type0;
8207 pedwarn ("comparison between pointer and integer");
8209 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8211 result_type = type1;
8212 pedwarn ("comparison between pointer and integer");
8220 build_type = integer_type_node;
8221 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8222 || code0 == FIXED_POINT_TYPE)
8223 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8224 || code1 == FIXED_POINT_TYPE))
8226 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8228 if (comp_target_types (type0, type1))
8230 result_type = common_pointer_type (type0, type1);
8231 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8232 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8233 pedwarn ("comparison of complete and incomplete pointers");
8235 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8236 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8240 result_type = ptr_type_node;
8241 pedwarn ("comparison of distinct pointer types lacks a cast");
8244 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8246 result_type = type0;
8247 if (pedantic || extra_warnings)
8248 pedwarn ("ordered comparison of pointer with integer zero");
8250 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8252 result_type = type1;
8254 pedwarn ("ordered comparison of pointer with integer zero");
8256 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8258 result_type = type0;
8259 pedwarn ("comparison between pointer and integer");
8261 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8263 result_type = type1;
8264 pedwarn ("comparison between pointer and integer");
8272 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8273 return error_mark_node;
8275 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8276 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8277 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8278 TREE_TYPE (type1))))
8280 binary_op_error (code, type0, type1);
8281 return error_mark_node;
8284 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8285 || code0 == FIXED_POINT_TYPE || code0 == VECTOR_TYPE)
8287 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8288 || code1 == FIXED_POINT_TYPE || code1 == VECTOR_TYPE))
8290 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8292 if (shorten || common || short_compare)
8294 result_type = c_common_type (type0, type1);
8295 if (result_type == error_mark_node)
8296 return error_mark_node;
8299 /* For certain operations (which identify themselves by shorten != 0)
8300 if both args were extended from the same smaller type,
8301 do the arithmetic in that type and then extend.
8303 shorten !=0 and !=1 indicates a bitwise operation.
8304 For them, this optimization is safe only if
8305 both args are zero-extended or both are sign-extended.
8306 Otherwise, we might change the result.
8307 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8308 but calculated in (unsigned short) it would be (unsigned short)-1. */
8310 if (shorten && none_complex)
8312 int unsigned0, unsigned1;
8317 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8318 excessive narrowing when we call get_narrower below. For
8319 example, suppose that OP0 is of unsigned int extended
8320 from signed char and that RESULT_TYPE is long long int.
8321 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8324 (long long int) (unsigned int) signed_char
8326 which get_narrower would narrow down to
8328 (unsigned int) signed char
8330 If we do not cast OP0 first, get_narrower would return
8331 signed_char, which is inconsistent with the case of the
8333 op0 = convert (result_type, op0);
8334 op1 = convert (result_type, op1);
8336 arg0 = get_narrower (op0, &unsigned0);
8337 arg1 = get_narrower (op1, &unsigned1);
8339 /* UNS is 1 if the operation to be done is an unsigned one. */
8340 uns = TYPE_UNSIGNED (result_type);
8342 final_type = result_type;
8344 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8345 but it *requires* conversion to FINAL_TYPE. */
8347 if ((TYPE_PRECISION (TREE_TYPE (op0))
8348 == TYPE_PRECISION (TREE_TYPE (arg0)))
8349 && TREE_TYPE (op0) != final_type)
8350 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8351 if ((TYPE_PRECISION (TREE_TYPE (op1))
8352 == TYPE_PRECISION (TREE_TYPE (arg1)))
8353 && TREE_TYPE (op1) != final_type)
8354 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8356 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8358 /* For bitwise operations, signedness of nominal type
8359 does not matter. Consider only how operands were extended. */
8363 /* Note that in all three cases below we refrain from optimizing
8364 an unsigned operation on sign-extended args.
8365 That would not be valid. */
8367 /* Both args variable: if both extended in same way
8368 from same width, do it in that width.
8369 Do it unsigned if args were zero-extended. */
8370 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8371 < TYPE_PRECISION (result_type))
8372 && (TYPE_PRECISION (TREE_TYPE (arg1))
8373 == TYPE_PRECISION (TREE_TYPE (arg0)))
8374 && unsigned0 == unsigned1
8375 && (unsigned0 || !uns))
8377 = c_common_signed_or_unsigned_type
8378 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8379 else if (TREE_CODE (arg0) == INTEGER_CST
8380 && (unsigned1 || !uns)
8381 && (TYPE_PRECISION (TREE_TYPE (arg1))
8382 < TYPE_PRECISION (result_type))
8384 = c_common_signed_or_unsigned_type (unsigned1,
8386 && !POINTER_TYPE_P (type)
8387 && int_fits_type_p (arg0, type))
8389 else if (TREE_CODE (arg1) == INTEGER_CST
8390 && (unsigned0 || !uns)
8391 && (TYPE_PRECISION (TREE_TYPE (arg0))
8392 < TYPE_PRECISION (result_type))
8394 = c_common_signed_or_unsigned_type (unsigned0,
8396 && !POINTER_TYPE_P (type)
8397 && int_fits_type_p (arg1, type))
8401 /* Shifts can be shortened if shifting right. */
8406 tree arg0 = get_narrower (op0, &unsigned_arg);
8408 final_type = result_type;
8410 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8411 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8413 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8414 /* We can shorten only if the shift count is less than the
8415 number of bits in the smaller type size. */
8416 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8417 /* We cannot drop an unsigned shift after sign-extension. */
8418 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8420 /* Do an unsigned shift if the operand was zero-extended. */
8422 = c_common_signed_or_unsigned_type (unsigned_arg,
8424 /* Convert value-to-be-shifted to that type. */
8425 if (TREE_TYPE (op0) != result_type)
8426 op0 = convert (result_type, op0);
8431 /* Comparison operations are shortened too but differently.
8432 They identify themselves by setting short_compare = 1. */
8436 /* Don't write &op0, etc., because that would prevent op0
8437 from being kept in a register.
8438 Instead, make copies of the our local variables and
8439 pass the copies by reference, then copy them back afterward. */
8440 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8441 enum tree_code xresultcode = resultcode;
8443 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8448 op0 = xop0, op1 = xop1;
8450 resultcode = xresultcode;
8452 if (warn_sign_compare && skip_evaluation == 0)
8454 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8455 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8456 int unsignedp0, unsignedp1;
8457 tree primop0 = get_narrower (op0, &unsignedp0);
8458 tree primop1 = get_narrower (op1, &unsignedp1);
8462 STRIP_TYPE_NOPS (xop0);
8463 STRIP_TYPE_NOPS (xop1);
8465 /* Give warnings for comparisons between signed and unsigned
8466 quantities that may fail.
8468 Do the checking based on the original operand trees, so that
8469 casts will be considered, but default promotions won't be.
8471 Do not warn if the comparison is being done in a signed type,
8472 since the signed type will only be chosen if it can represent
8473 all the values of the unsigned type. */
8474 if (!TYPE_UNSIGNED (result_type))
8476 /* Do not warn if both operands are the same signedness. */
8477 else if (op0_signed == op1_signed)
8485 sop = xop0, uop = xop1;
8487 sop = xop1, uop = xop0;
8489 /* Do not warn if the signed quantity is an
8490 unsuffixed integer literal (or some static
8491 constant expression involving such literals or a
8492 conditional expression involving such literals)
8493 and it is non-negative. */
8494 if (tree_expr_nonnegative_warnv_p (sop, &ovf))
8496 /* Do not warn if the comparison is an equality operation,
8497 the unsigned quantity is an integral constant, and it
8498 would fit in the result if the result were signed. */
8499 else if (TREE_CODE (uop) == INTEGER_CST
8500 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8502 (uop, c_common_signed_type (result_type)))
8504 /* Do not warn if the unsigned quantity is an enumeration
8505 constant and its maximum value would fit in the result
8506 if the result were signed. */
8507 else if (TREE_CODE (uop) == INTEGER_CST
8508 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8510 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8511 c_common_signed_type (result_type)))
8514 warning (OPT_Wsign_compare, "comparison between signed and unsigned");
8517 /* Warn if two unsigned values are being compared in a size
8518 larger than their original size, and one (and only one) is the
8519 result of a `~' operator. This comparison will always fail.
8521 Also warn if one operand is a constant, and the constant
8522 does not have all bits set that are set in the ~ operand
8523 when it is extended. */
8525 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8526 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8528 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8529 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8532 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8535 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8538 HOST_WIDE_INT constant, mask;
8539 int unsignedp, bits;
8541 if (host_integerp (primop0, 0))
8544 unsignedp = unsignedp1;
8545 constant = tree_low_cst (primop0, 0);
8550 unsignedp = unsignedp0;
8551 constant = tree_low_cst (primop1, 0);
8554 bits = TYPE_PRECISION (TREE_TYPE (primop));
8555 if (bits < TYPE_PRECISION (result_type)
8556 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8558 mask = (~(HOST_WIDE_INT) 0) << bits;
8559 if ((mask & constant) != mask)
8560 warning (OPT_Wsign_compare, "comparison of promoted ~unsigned with constant");
8563 else if (unsignedp0 && unsignedp1
8564 && (TYPE_PRECISION (TREE_TYPE (primop0))
8565 < TYPE_PRECISION (result_type))
8566 && (TYPE_PRECISION (TREE_TYPE (primop1))
8567 < TYPE_PRECISION (result_type)))
8568 warning (OPT_Wsign_compare, "comparison of promoted ~unsigned with unsigned");
8574 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8575 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8576 Then the expression will be built.
8577 It will be given type FINAL_TYPE if that is nonzero;
8578 otherwise, it will be given type RESULT_TYPE. */
8582 binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1));
8583 return error_mark_node;
8588 if (TREE_TYPE (op0) != result_type)
8589 op0 = convert_and_check (result_type, op0);
8590 if (TREE_TYPE (op1) != result_type)
8591 op1 = convert_and_check (result_type, op1);
8593 /* This can happen if one operand has a vector type, and the other
8594 has a different type. */
8595 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8596 return error_mark_node;
8599 if (build_type == NULL_TREE)
8600 build_type = result_type;
8603 /* Treat expressions in initializers specially as they can't trap. */
8604 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8607 : fold_build2 (resultcode, build_type,
8610 if (final_type != 0)
8611 result = convert (final_type, result);
8617 /* Convert EXPR to be a truth-value, validating its type for this
8621 c_objc_common_truthvalue_conversion (tree expr)
8623 switch (TREE_CODE (TREE_TYPE (expr)))
8626 error ("used array that cannot be converted to pointer where scalar is required");
8627 return error_mark_node;
8630 error ("used struct type value where scalar is required");
8631 return error_mark_node;
8634 error ("used union type value where scalar is required");
8635 return error_mark_node;
8644 /* ??? Should we also give an error for void and vectors rather than
8645 leaving those to give errors later? */
8646 return c_common_truthvalue_conversion (expr);
8650 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8654 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, bool *se)
8656 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8658 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8659 /* Executing a compound literal inside a function reinitializes
8661 if (!TREE_STATIC (decl))
8669 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8672 c_begin_omp_parallel (void)
8677 block = c_begin_compound_stmt (true);
8682 /* Generate OMP_PARALLEL, with CLAUSES and BLOCK as its compound statement. */
8685 c_finish_omp_parallel (tree clauses, tree block)
8689 block = c_end_compound_stmt (block, true);
8691 stmt = make_node (OMP_PARALLEL);
8692 TREE_TYPE (stmt) = void_type_node;
8693 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8694 OMP_PARALLEL_BODY (stmt) = block;
8696 return add_stmt (stmt);
8699 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8702 c_begin_omp_task (void)
8707 block = c_begin_compound_stmt (true);
8712 /* Generate OMP_TASK, with CLAUSES and BLOCK as its compound statement. */
8715 c_finish_omp_task (tree clauses, tree block)
8719 block = c_end_compound_stmt (block, true);
8721 stmt = make_node (OMP_TASK);
8722 TREE_TYPE (stmt) = void_type_node;
8723 OMP_TASK_CLAUSES (stmt) = clauses;
8724 OMP_TASK_BODY (stmt) = block;
8726 return add_stmt (stmt);
8729 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
8730 Remove any elements from the list that are invalid. */
8733 c_finish_omp_clauses (tree clauses)
8735 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8736 tree c, t, *pc = &clauses;
8739 bitmap_obstack_initialize (NULL);
8740 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8741 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8742 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8744 for (pc = &clauses, c = clauses; c ; c = *pc)
8746 bool remove = false;
8747 bool need_complete = false;
8748 bool need_implicitly_determined = false;
8750 switch (OMP_CLAUSE_CODE (c))
8752 case OMP_CLAUSE_SHARED:
8754 need_implicitly_determined = true;
8755 goto check_dup_generic;
8757 case OMP_CLAUSE_PRIVATE:
8759 need_complete = true;
8760 need_implicitly_determined = true;
8761 goto check_dup_generic;
8763 case OMP_CLAUSE_REDUCTION:
8765 need_implicitly_determined = true;
8766 t = OMP_CLAUSE_DECL (c);
8767 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8768 || POINTER_TYPE_P (TREE_TYPE (t)))
8770 error ("%qE has invalid type for %<reduction%>", t);
8773 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8775 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8776 const char *r_name = NULL;
8793 case TRUTH_ANDIF_EXPR:
8796 case TRUTH_ORIF_EXPR:
8804 error ("%qE has invalid type for %<reduction(%s)%>",
8809 goto check_dup_generic;
8811 case OMP_CLAUSE_COPYPRIVATE:
8812 name = "copyprivate";
8813 goto check_dup_generic;
8815 case OMP_CLAUSE_COPYIN:
8817 t = OMP_CLAUSE_DECL (c);
8818 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8820 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8823 goto check_dup_generic;
8826 t = OMP_CLAUSE_DECL (c);
8827 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8829 error ("%qE is not a variable in clause %qs", t, name);
8832 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8833 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8834 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8836 error ("%qE appears more than once in data clauses", t);
8840 bitmap_set_bit (&generic_head, DECL_UID (t));
8843 case OMP_CLAUSE_FIRSTPRIVATE:
8844 name = "firstprivate";
8845 t = OMP_CLAUSE_DECL (c);
8846 need_complete = true;
8847 need_implicitly_determined = true;
8848 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8850 error ("%qE is not a variable in clause %<firstprivate%>", t);
8853 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8854 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8856 error ("%qE appears more than once in data clauses", t);
8860 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8863 case OMP_CLAUSE_LASTPRIVATE:
8864 name = "lastprivate";
8865 t = OMP_CLAUSE_DECL (c);
8866 need_complete = true;
8867 need_implicitly_determined = true;
8868 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8870 error ("%qE is not a variable in clause %<lastprivate%>", t);
8873 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8874 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8876 error ("%qE appears more than once in data clauses", t);
8880 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8884 case OMP_CLAUSE_NUM_THREADS:
8885 case OMP_CLAUSE_SCHEDULE:
8886 case OMP_CLAUSE_NOWAIT:
8887 case OMP_CLAUSE_ORDERED:
8888 case OMP_CLAUSE_DEFAULT:
8889 case OMP_CLAUSE_UNTIED:
8890 case OMP_CLAUSE_COLLAPSE:
8891 pc = &OMP_CLAUSE_CHAIN (c);
8900 t = OMP_CLAUSE_DECL (c);
8904 t = require_complete_type (t);
8905 if (t == error_mark_node)
8909 if (need_implicitly_determined)
8911 const char *share_name = NULL;
8913 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8914 share_name = "threadprivate";
8915 else switch (c_omp_predetermined_sharing (t))
8917 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8919 case OMP_CLAUSE_DEFAULT_SHARED:
8920 share_name = "shared";
8922 case OMP_CLAUSE_DEFAULT_PRIVATE:
8923 share_name = "private";
8930 error ("%qE is predetermined %qs for %qs",
8931 t, share_name, name);
8938 *pc = OMP_CLAUSE_CHAIN (c);
8940 pc = &OMP_CLAUSE_CHAIN (c);
8943 bitmap_obstack_release (NULL);
8947 /* Make a variant type in the proper way for C/C++, propagating qualifiers
8948 down to the element type of an array. */
8951 c_build_qualified_type (tree type, int type_quals)
8953 if (type == error_mark_node)
8956 if (TREE_CODE (type) == ARRAY_TYPE)
8959 tree element_type = c_build_qualified_type (TREE_TYPE (type),
8962 /* See if we already have an identically qualified type. */
8963 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
8965 if (TYPE_QUALS (strip_array_types (t)) == type_quals
8966 && TYPE_NAME (t) == TYPE_NAME (type)
8967 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type)
8968 && attribute_list_equal (TYPE_ATTRIBUTES (t),
8969 TYPE_ATTRIBUTES (type)))
8974 tree domain = TYPE_DOMAIN (type);
8976 t = build_variant_type_copy (type);
8977 TREE_TYPE (t) = element_type;
8979 if (TYPE_STRUCTURAL_EQUALITY_P (element_type)
8980 || (domain && TYPE_STRUCTURAL_EQUALITY_P (domain)))
8981 SET_TYPE_STRUCTURAL_EQUALITY (t);
8982 else if (TYPE_CANONICAL (element_type) != element_type
8983 || (domain && TYPE_CANONICAL (domain) != domain))
8985 tree unqualified_canon
8986 = build_array_type (TYPE_CANONICAL (element_type),
8987 domain? TYPE_CANONICAL (domain)
8990 = c_build_qualified_type (unqualified_canon, type_quals);
8993 TYPE_CANONICAL (t) = t;
8998 /* A restrict-qualified pointer type must be a pointer to object or
8999 incomplete type. Note that the use of POINTER_TYPE_P also allows
9000 REFERENCE_TYPEs, which is appropriate for C++. */
9001 if ((type_quals & TYPE_QUAL_RESTRICT)
9002 && (!POINTER_TYPE_P (type)
9003 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
9005 error ("invalid use of %<restrict%>");
9006 type_quals &= ~TYPE_QUAL_RESTRICT;
9009 return build_qualified_type (type, type_quals);