1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Hacked by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization. */
31 #include "coretypes.h"
38 #include "diagnostic.h"
42 #include "c-family/c-common.h"
45 static tree pfn_from_ptrmemfunc (tree);
46 static tree delta_from_ptrmemfunc (tree);
47 static tree convert_for_assignment (tree, tree, impl_conv_rhs, tree, int,
49 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
50 static tree rationalize_conditional_expr (enum tree_code, tree,
52 static int comp_ptr_ttypes_real (tree, tree, int);
53 static bool comp_except_types (tree, tree, bool);
54 static bool comp_array_types (const_tree, const_tree, bool);
55 static tree pointer_diff (tree, tree, tree);
56 static tree get_delta_difference (tree, tree, bool, bool);
57 static void casts_away_constness_r (tree *, tree *);
58 static bool casts_away_constness (tree, tree);
59 static void maybe_warn_about_returning_address_of_local (tree);
60 static tree lookup_destructor (tree, tree, tree);
61 static void warn_args_num (location_t, tree, bool);
62 static int convert_arguments (tree, VEC(tree,gc) **, tree, int,
65 /* Do `exp = require_complete_type (exp);' to make sure exp
66 does not have an incomplete type. (That includes void types.)
67 Returns the error_mark_node if the VALUE does not have
68 complete type when this function returns. */
71 require_complete_type (tree value)
75 if (processing_template_decl || value == error_mark_node)
78 if (TREE_CODE (value) == OVERLOAD)
79 type = unknown_type_node;
81 type = TREE_TYPE (value);
83 if (type == error_mark_node)
84 return error_mark_node;
86 /* First, detect a valid value with a complete type. */
87 if (COMPLETE_TYPE_P (type))
90 if (complete_type_or_else (type, value))
93 return error_mark_node;
96 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
97 a template instantiation, do the instantiation. Returns TYPE,
98 whether or not it could be completed, unless something goes
99 horribly wrong, in which case the error_mark_node is returned. */
102 complete_type (tree type)
104 if (type == NULL_TREE)
105 /* Rather than crash, we return something sure to cause an error
107 return error_mark_node;
109 if (type == error_mark_node || COMPLETE_TYPE_P (type))
111 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
113 tree t = complete_type (TREE_TYPE (type));
114 unsigned int needs_constructing, has_nontrivial_dtor;
115 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
118 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
120 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
121 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
123 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
124 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
127 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
128 instantiate_class_template (TYPE_MAIN_VARIANT (type));
133 /* Like complete_type, but issue an error if the TYPE cannot be completed.
134 VALUE is used for informative diagnostics.
135 Returns NULL_TREE if the type cannot be made complete. */
138 complete_type_or_else (tree type, tree value)
140 type = complete_type (type);
141 if (type == error_mark_node)
142 /* We already issued an error. */
144 else if (!COMPLETE_TYPE_P (type))
146 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
153 /* Return truthvalue of whether type of EXP is instantiated. */
156 type_unknown_p (const_tree exp)
158 return (TREE_CODE (exp) == TREE_LIST
159 || TREE_TYPE (exp) == unknown_type_node);
163 /* Return the common type of two parameter lists.
164 We assume that comptypes has already been done and returned 1;
165 if that isn't so, this may crash.
167 As an optimization, free the space we allocate if the parameter
168 lists are already common. */
171 commonparms (tree p1, tree p2)
173 tree oldargs = p1, newargs, n;
177 len = list_length (p1);
178 newargs = tree_last (p1);
180 if (newargs == void_list_node)
189 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
194 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
196 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
198 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
201 else if (! TREE_PURPOSE (p1))
203 if (TREE_PURPOSE (p2))
205 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
211 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
213 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
215 if (TREE_VALUE (p1) != TREE_VALUE (p2))
218 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
221 TREE_VALUE (n) = TREE_VALUE (p1);
229 /* Given a type, perhaps copied for a typedef,
230 find the "original" version of it. */
232 original_type (tree t)
234 int quals = cp_type_quals (t);
235 while (t != error_mark_node
236 && TYPE_NAME (t) != NULL_TREE)
238 tree x = TYPE_NAME (t);
239 if (TREE_CODE (x) != TYPE_DECL)
241 x = DECL_ORIGINAL_TYPE (x);
246 return cp_build_qualified_type (t, quals);
249 /* Return the common type for two arithmetic types T1 and T2 under the
250 usual arithmetic conversions. The default conversions have already
251 been applied, and enumerated types converted to their compatible
255 cp_common_type (tree t1, tree t2)
257 enum tree_code code1 = TREE_CODE (t1);
258 enum tree_code code2 = TREE_CODE (t2);
261 /* In what follows, we slightly generalize the rules given in [expr] so
262 as to deal with `long long' and `complex'. First, merge the
264 attributes = (*targetm.merge_type_attributes) (t1, t2);
266 if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2))
268 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
269 return build_type_attribute_variant (t1, attributes);
274 /* FIXME: Attributes. */
275 gcc_assert (ARITHMETIC_TYPE_P (t1)
276 || TREE_CODE (t1) == VECTOR_TYPE
277 || UNSCOPED_ENUM_P (t1));
278 gcc_assert (ARITHMETIC_TYPE_P (t2)
279 || TREE_CODE (t2) == VECTOR_TYPE
280 || UNSCOPED_ENUM_P (t2));
282 /* If one type is complex, form the common type of the non-complex
283 components, then make that complex. Use T1 or T2 if it is the
285 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
287 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
288 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
290 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
292 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
293 return build_type_attribute_variant (t1, attributes);
294 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
295 return build_type_attribute_variant (t2, attributes);
297 return build_type_attribute_variant (build_complex_type (subtype),
301 if (code1 == VECTOR_TYPE)
303 /* When we get here we should have two vectors of the same size.
304 Just prefer the unsigned one if present. */
305 if (TYPE_UNSIGNED (t1))
306 return build_type_attribute_variant (t1, attributes);
308 return build_type_attribute_variant (t2, attributes);
311 /* If only one is real, use it as the result. */
312 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
313 return build_type_attribute_variant (t1, attributes);
314 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
315 return build_type_attribute_variant (t2, attributes);
317 /* Both real or both integers; use the one with greater precision. */
318 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
319 return build_type_attribute_variant (t1, attributes);
320 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
321 return build_type_attribute_variant (t2, attributes);
323 /* The types are the same; no need to do anything fancy. */
324 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
325 return build_type_attribute_variant (t1, attributes);
327 if (code1 != REAL_TYPE)
329 /* If one is unsigned long long, then convert the other to unsigned
331 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
332 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
333 return build_type_attribute_variant (long_long_unsigned_type_node,
335 /* If one is a long long, and the other is an unsigned long, and
336 long long can represent all the values of an unsigned long, then
337 convert to a long long. Otherwise, convert to an unsigned long
338 long. Otherwise, if either operand is long long, convert the
341 Since we're here, we know the TYPE_PRECISION is the same;
342 therefore converting to long long cannot represent all the values
343 of an unsigned long, so we choose unsigned long long in that
345 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
346 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
348 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
349 ? long_long_unsigned_type_node
350 : long_long_integer_type_node);
351 return build_type_attribute_variant (t, attributes);
353 if (int128_integer_type_node != NULL_TREE
354 && (same_type_p (TYPE_MAIN_VARIANT (t1),
355 int128_integer_type_node)
356 || same_type_p (TYPE_MAIN_VARIANT (t2),
357 int128_integer_type_node)))
359 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
360 ? int128_unsigned_type_node
361 : int128_integer_type_node);
362 return build_type_attribute_variant (t, attributes);
365 /* Go through the same procedure, but for longs. */
366 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
367 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
368 return build_type_attribute_variant (long_unsigned_type_node,
370 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
371 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
373 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
374 ? long_unsigned_type_node : long_integer_type_node);
375 return build_type_attribute_variant (t, attributes);
377 /* Otherwise prefer the unsigned one. */
378 if (TYPE_UNSIGNED (t1))
379 return build_type_attribute_variant (t1, attributes);
381 return build_type_attribute_variant (t2, attributes);
385 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
386 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
387 return build_type_attribute_variant (long_double_type_node,
389 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
390 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
391 return build_type_attribute_variant (double_type_node,
393 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
394 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
395 return build_type_attribute_variant (float_type_node,
398 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
399 the standard C++ floating-point types. Logic earlier in this
400 function has already eliminated the possibility that
401 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
402 compelling reason to choose one or the other. */
403 return build_type_attribute_variant (t1, attributes);
407 /* T1 and T2 are arithmetic or enumeration types. Return the type
408 that will result from the "usual arithmetic conversions" on T1 and
409 T2 as described in [expr]. */
412 type_after_usual_arithmetic_conversions (tree t1, tree t2)
414 gcc_assert (ARITHMETIC_TYPE_P (t1)
415 || TREE_CODE (t1) == VECTOR_TYPE
416 || UNSCOPED_ENUM_P (t1));
417 gcc_assert (ARITHMETIC_TYPE_P (t2)
418 || TREE_CODE (t2) == VECTOR_TYPE
419 || UNSCOPED_ENUM_P (t2));
421 /* Perform the integral promotions. We do not promote real types here. */
422 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
423 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
425 t1 = type_promotes_to (t1);
426 t2 = type_promotes_to (t2);
429 return cp_common_type (t1, t2);
432 /* Subroutine of composite_pointer_type to implement the recursive
433 case. See that function for documentation of the parameters. */
436 composite_pointer_type_r (tree t1, tree t2,
437 composite_pointer_operation operation,
438 tsubst_flags_t complain)
445 /* Determine the types pointed to by T1 and T2. */
446 if (TREE_CODE (t1) == POINTER_TYPE)
448 pointee1 = TREE_TYPE (t1);
449 pointee2 = TREE_TYPE (t2);
453 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
454 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
459 Otherwise, the composite pointer type is a pointer type
460 similar (_conv.qual_) to the type of one of the operands,
461 with a cv-qualification signature (_conv.qual_) that is the
462 union of the cv-qualification signatures of the operand
464 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
465 result_type = pointee1;
466 else if ((TREE_CODE (pointee1) == POINTER_TYPE
467 && TREE_CODE (pointee2) == POINTER_TYPE)
468 || (TYPE_PTR_TO_MEMBER_P (pointee1)
469 && TYPE_PTR_TO_MEMBER_P (pointee2)))
470 result_type = composite_pointer_type_r (pointee1, pointee2, operation,
474 if (complain & tf_error)
479 permerror (input_location, "comparison between "
480 "distinct pointer types %qT and %qT lacks a cast",
484 permerror (input_location, "conversion between "
485 "distinct pointer types %qT and %qT lacks a cast",
488 case CPO_CONDITIONAL_EXPR:
489 permerror (input_location, "conditional expression between "
490 "distinct pointer types %qT and %qT lacks a cast",
497 result_type = void_type_node;
499 result_type = cp_build_qualified_type (result_type,
500 (cp_type_quals (pointee1)
501 | cp_type_quals (pointee2)));
502 /* If the original types were pointers to members, so is the
504 if (TYPE_PTR_TO_MEMBER_P (t1))
506 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
507 TYPE_PTRMEM_CLASS_TYPE (t2))
508 && (complain & tf_error))
513 permerror (input_location, "comparison between "
514 "distinct pointer types %qT and %qT lacks a cast",
518 permerror (input_location, "conversion between "
519 "distinct pointer types %qT and %qT lacks a cast",
522 case CPO_CONDITIONAL_EXPR:
523 permerror (input_location, "conditional expression between "
524 "distinct pointer types %qT and %qT lacks a cast",
531 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
535 result_type = build_pointer_type (result_type);
537 /* Merge the attributes. */
538 attributes = (*targetm.merge_type_attributes) (t1, t2);
539 return build_type_attribute_variant (result_type, attributes);
542 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
543 ARG1 and ARG2 are the values with those types. The OPERATION is to
544 describe the operation between the pointer types,
545 in case an error occurs.
547 This routine also implements the computation of a common type for
548 pointers-to-members as per [expr.eq]. */
551 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
552 composite_pointer_operation operation,
553 tsubst_flags_t complain)
560 If one operand is a null pointer constant, the composite pointer
561 type is the type of the other operand. */
562 if (null_ptr_cst_p (arg1))
564 if (null_ptr_cst_p (arg2))
571 If one of the operands has type "pointer to cv1 void*", then
572 the other has type "pointer to cv2T", and the composite pointer
573 type is "pointer to cv12 void", where cv12 is the union of cv1
576 If either type is a pointer to void, make sure it is T1. */
577 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
585 /* Now, if T1 is a pointer to void, merge the qualifiers. */
586 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
591 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
596 pedwarn (input_location, OPT_pedantic,
597 "ISO C++ forbids comparison between "
598 "pointer of type %<void *%> and pointer-to-function");
601 pedwarn (input_location, OPT_pedantic,
602 "ISO C++ forbids conversion between "
603 "pointer of type %<void *%> and pointer-to-function");
605 case CPO_CONDITIONAL_EXPR:
606 pedwarn (input_location, OPT_pedantic,
607 "ISO C++ forbids conditional expression between "
608 "pointer of type %<void *%> and pointer-to-function");
615 = cp_build_qualified_type (void_type_node,
616 (cp_type_quals (TREE_TYPE (t1))
617 | cp_type_quals (TREE_TYPE (t2))));
618 result_type = build_pointer_type (result_type);
619 /* Merge the attributes. */
620 attributes = (*targetm.merge_type_attributes) (t1, t2);
621 return build_type_attribute_variant (result_type, attributes);
624 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
625 && TREE_CODE (t2) == POINTER_TYPE)
627 if (objc_compare_types (t1, t2, -3, NULL_TREE))
631 /* [expr.eq] permits the application of a pointer conversion to
632 bring the pointers to a common type. */
633 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
634 && CLASS_TYPE_P (TREE_TYPE (t1))
635 && CLASS_TYPE_P (TREE_TYPE (t2))
636 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
639 class1 = TREE_TYPE (t1);
640 class2 = TREE_TYPE (t2);
642 if (DERIVED_FROM_P (class1, class2))
643 t2 = (build_pointer_type
644 (cp_build_qualified_type (class1, cp_type_quals (class2))));
645 else if (DERIVED_FROM_P (class2, class1))
646 t1 = (build_pointer_type
647 (cp_build_qualified_type (class2, cp_type_quals (class1))));
650 if (complain & tf_error)
654 error ("comparison between distinct "
655 "pointer types %qT and %qT lacks a cast", t1, t2);
658 error ("conversion between distinct "
659 "pointer types %qT and %qT lacks a cast", t1, t2);
661 case CPO_CONDITIONAL_EXPR:
662 error ("conditional expression between distinct "
663 "pointer types %qT and %qT lacks a cast", t1, t2);
668 return error_mark_node;
671 /* [expr.eq] permits the application of a pointer-to-member
672 conversion to change the class type of one of the types. */
673 else if (TYPE_PTR_TO_MEMBER_P (t1)
674 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
675 TYPE_PTRMEM_CLASS_TYPE (t2)))
677 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
678 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
680 if (DERIVED_FROM_P (class1, class2))
681 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
682 else if (DERIVED_FROM_P (class2, class1))
683 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
686 if (complain & tf_error)
690 error ("comparison between distinct "
691 "pointer-to-member types %qT and %qT lacks a cast",
695 error ("conversion between distinct "
696 "pointer-to-member types %qT and %qT lacks a cast",
699 case CPO_CONDITIONAL_EXPR:
700 error ("conditional expression between distinct "
701 "pointer-to-member types %qT and %qT lacks a cast",
707 return error_mark_node;
711 return composite_pointer_type_r (t1, t2, operation, complain);
714 /* Return the merged type of two types.
715 We assume that comptypes has already been done and returned 1;
716 if that isn't so, this may crash.
718 This just combines attributes and default arguments; any other
719 differences would cause the two types to compare unalike. */
722 merge_types (tree t1, tree t2)
724 enum tree_code code1;
725 enum tree_code code2;
728 /* Save time if the two types are the same. */
731 if (original_type (t1) == original_type (t2))
734 /* If one type is nonsense, use the other. */
735 if (t1 == error_mark_node)
737 if (t2 == error_mark_node)
740 /* Merge the attributes. */
741 attributes = (*targetm.merge_type_attributes) (t1, t2);
743 if (TYPE_PTRMEMFUNC_P (t1))
744 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
745 if (TYPE_PTRMEMFUNC_P (t2))
746 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
748 code1 = TREE_CODE (t1);
749 code2 = TREE_CODE (t2);
752 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
753 if (code1 == TYPENAME_TYPE)
755 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
756 code1 = TREE_CODE (t1);
760 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
761 code2 = TREE_CODE (t2);
769 /* For two pointers, do this recursively on the target type. */
771 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
772 int quals = cp_type_quals (t1);
774 if (code1 == POINTER_TYPE)
775 t1 = build_pointer_type (target);
777 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
778 t1 = build_type_attribute_variant (t1, attributes);
779 t1 = cp_build_qualified_type (t1, quals);
781 if (TREE_CODE (target) == METHOD_TYPE)
782 t1 = build_ptrmemfunc_type (t1);
791 quals = cp_type_quals (t1);
792 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
793 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
794 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
796 t1 = cp_build_qualified_type (t1, quals);
802 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
803 /* Save space: see if the result is identical to one of the args. */
804 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
805 return build_type_attribute_variant (t1, attributes);
806 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
807 return build_type_attribute_variant (t2, attributes);
808 /* Merge the element types, and have a size if either arg has one. */
809 t1 = build_cplus_array_type
810 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
815 /* Function types: prefer the one that specified arg types.
816 If both do, merge the arg types. Also merge the return types. */
818 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
819 tree p1 = TYPE_ARG_TYPES (t1);
820 tree p2 = TYPE_ARG_TYPES (t2);
824 /* Save space: see if the result is identical to one of the args. */
825 if (valtype == TREE_TYPE (t1) && ! p2)
826 return cp_build_type_attribute_variant (t1, attributes);
827 if (valtype == TREE_TYPE (t2) && ! p1)
828 return cp_build_type_attribute_variant (t2, attributes);
830 /* Simple way if one arg fails to specify argument types. */
831 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
833 else if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
836 parms = commonparms (p1, p2);
838 rval = build_function_type (valtype, parms);
839 gcc_assert (type_memfn_quals (t1) == type_memfn_quals (t2));
840 rval = apply_memfn_quals (rval, type_memfn_quals (t1));
841 raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
842 TYPE_RAISES_EXCEPTIONS (t2));
843 t1 = build_exception_variant (rval, raises);
849 /* Get this value the long way, since TYPE_METHOD_BASETYPE
850 is just the main variant of this. */
851 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
852 tree raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
853 TYPE_RAISES_EXCEPTIONS (t2));
856 /* If this was a member function type, get back to the
857 original type of type member function (i.e., without
858 the class instance variable up front. */
859 t1 = build_function_type (TREE_TYPE (t1),
860 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
861 t2 = build_function_type (TREE_TYPE (t2),
862 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
863 t3 = merge_types (t1, t2);
864 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
865 TYPE_ARG_TYPES (t3));
866 t1 = build_exception_variant (t3, raises);
871 /* There is no need to merge attributes into a TYPENAME_TYPE.
872 When the type is instantiated it will have whatever
873 attributes result from the instantiation. */
879 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
881 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
884 return cp_build_type_attribute_variant (t1, attributes);
887 /* Return the ARRAY_TYPE type without its domain. */
890 strip_array_domain (tree type)
893 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
894 if (TYPE_DOMAIN (type) == NULL_TREE)
896 t2 = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
897 return cp_build_type_attribute_variant (t2, TYPE_ATTRIBUTES (type));
900 /* Wrapper around cp_common_type that is used by c-common.c and other
901 front end optimizations that remove promotions.
903 Return the common type for two arithmetic types T1 and T2 under the
904 usual arithmetic conversions. The default conversions have already
905 been applied, and enumerated types converted to their compatible
909 common_type (tree t1, tree t2)
911 /* If one type is nonsense, use the other */
912 if (t1 == error_mark_node)
914 if (t2 == error_mark_node)
917 return cp_common_type (t1, t2);
920 /* Return the common type of two pointer types T1 and T2. This is the
921 type for the result of most arithmetic operations if the operands
922 have the given two types.
924 We assume that comp_target_types has already been done and returned
925 nonzero; if that isn't so, this may crash. */
928 common_pointer_type (tree t1, tree t2)
930 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
931 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
932 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
934 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
935 CPO_CONVERSION, tf_warning_or_error);
938 /* Compare two exception specifier types for exactness or subsetness, if
939 allowed. Returns false for mismatch, true for match (same, or
942 [except.spec] "If a class X ... objects of class X or any class publicly
943 and unambiguously derived from X. Similarly, if a pointer type Y * ...
944 exceptions of type Y * or that are pointers to any type publicly and
945 unambiguously derived from Y. Otherwise a function only allows exceptions
946 that have the same type ..."
947 This does not mention cv qualifiers and is different to what throw
948 [except.throw] and catch [except.catch] will do. They will ignore the
949 top level cv qualifiers, and allow qualifiers in the pointer to class
952 We implement the letter of the standard. */
955 comp_except_types (tree a, tree b, bool exact)
957 if (same_type_p (a, b))
961 if (cp_type_quals (a) || cp_type_quals (b))
964 if (TREE_CODE (a) == POINTER_TYPE
965 && TREE_CODE (b) == POINTER_TYPE)
969 if (cp_type_quals (a) || cp_type_quals (b))
973 if (TREE_CODE (a) != RECORD_TYPE
974 || TREE_CODE (b) != RECORD_TYPE)
977 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
983 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
984 If EXACT is ce_derived, T2 can be stricter than T1 (according to 15.4/5).
985 If EXACT is ce_normal, the compatibility rules in 15.4/3 apply.
986 If EXACT is ce_exact, the specs must be exactly the same. Exception lists
987 are unordered, but we've already filtered out duplicates. Most lists will
988 be in order, we should try to make use of that. */
991 comp_except_specs (const_tree t1, const_tree t2, int exact)
996 const_tree noexcept_spec = NULL_TREE;
997 const_tree other_spec;
1002 /* First test noexcept compatibility. */
1003 if (t1 && TREE_PURPOSE (t1))
1004 noexcept_spec = t1, other_spec = t2;
1005 else if (t2 && TREE_PURPOSE (t2))
1006 noexcept_spec = t2, other_spec = t1;
1009 tree p = TREE_PURPOSE (noexcept_spec);
1010 /* Two noexcept-specs are equivalent iff their exprs are. */
1011 if (other_spec && TREE_PURPOSE (other_spec))
1012 return cp_tree_equal (p, TREE_PURPOSE (other_spec));
1013 /* noexcept(true) is compatible with throw(). */
1014 else if (exact < ce_exact && p == boolean_true_node)
1015 return nothrow_spec_p (other_spec);
1016 /* noexcept(false) is compatible with any throwing
1017 dynamic-exception-spec. */
1018 else if (exact < ce_exact && p == boolean_false_node)
1019 return !nothrow_spec_p (other_spec);
1020 /* A dependent noexcept-spec is not compatible with any
1021 dynamic-exception-spec. */
1026 if (t1 == NULL_TREE) /* T1 is ... */
1027 return t2 == NULL_TREE || exact == ce_derived;
1028 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
1029 return t2 != NULL_TREE && !TREE_VALUE (t2);
1030 if (t2 == NULL_TREE) /* T2 is ... */
1032 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
1033 return exact == ce_derived;
1035 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
1036 Count how many we find, to determine exactness. For exact matching and
1037 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
1039 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
1041 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
1043 tree a = TREE_VALUE (probe);
1044 tree b = TREE_VALUE (t2);
1046 if (comp_except_types (a, b, exact))
1048 if (probe == base && exact > ce_derived)
1049 base = TREE_CHAIN (probe);
1054 if (probe == NULL_TREE)
1057 return exact == ce_derived || base == NULL_TREE || length == list_length (t1);
1060 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
1061 [] can match [size]. */
1064 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
1073 /* The type of the array elements must be the same. */
1074 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1077 d1 = TYPE_DOMAIN (t1);
1078 d2 = TYPE_DOMAIN (t2);
1083 /* If one of the arrays is dimensionless, and the other has a
1084 dimension, they are of different types. However, it is valid to
1092 declarations for an array object can specify
1093 array types that differ by the presence or absence of a major
1094 array bound (_dcl.array_). */
1096 return allow_redeclaration;
1098 /* Check that the dimensions are the same. */
1100 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
1102 max1 = TYPE_MAX_VALUE (d1);
1103 max2 = TYPE_MAX_VALUE (d2);
1104 if (processing_template_decl && !abi_version_at_least (2)
1105 && !value_dependent_expression_p (max1)
1106 && !value_dependent_expression_p (max2))
1108 /* With abi-1 we do not fold non-dependent array bounds, (and
1109 consequently mangle them incorrectly). We must therefore
1110 fold them here, to verify the domains have the same
1116 if (!cp_tree_equal (max1, max2))
1122 /* Compare the relative position of T1 and T2 into their respective
1123 template parameter list.
1124 T1 and T2 must be template parameter types.
1125 Return TRUE if T1 and T2 have the same position, FALSE otherwise. */
1128 comp_template_parms_position (tree t1, tree t2)
1130 gcc_assert (t1 && t2
1131 && TREE_CODE (t1) == TREE_CODE (t2)
1132 && (TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM
1133 || TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM
1134 || TREE_CODE (t1) == TEMPLATE_TYPE_PARM));
1136 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1137 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1138 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1139 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1145 /* Subroutine of incompatible_dependent_types_p.
1146 Return the template parameter of the dependent type T.
1147 If T is a typedef, return the template parameters of
1148 the _decl_ of the typedef. T must be a dependent type. */
1151 get_template_parms_of_dependent_type (tree t)
1153 tree tinfo = NULL_TREE, tparms = NULL_TREE;
1155 /* First, try the obvious case of getting the
1156 template info from T itself. */
1157 if ((tinfo = get_template_info (t)))
1159 else if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
1160 return TEMPLATE_TYPE_PARM_SIBLING_PARMS (t);
1161 else if (typedef_variant_p (t)
1162 && !NAMESPACE_SCOPE_P (TYPE_NAME (t)))
1163 tinfo = get_template_info (DECL_CONTEXT (TYPE_NAME (t)));
1164 /* If T is a TYPENAME_TYPE which context is a template type
1165 parameter, get the template parameters from that context. */
1166 else if (TYPE_CONTEXT (t)
1167 && TREE_CODE (TYPE_CONTEXT (t)) == TEMPLATE_TYPE_PARM)
1168 return TEMPLATE_TYPE_PARM_SIBLING_PARMS (TYPE_CONTEXT (t));
1169 else if (TYPE_CONTEXT (t)
1170 && !NAMESPACE_SCOPE_P (t))
1171 tinfo = get_template_info (TYPE_CONTEXT (t));
1174 tparms = DECL_TEMPLATE_PARMS (TI_TEMPLATE (tinfo));
1179 /* Subroutine of structural_comptypes.
1180 Compare the dependent types T1 and T2.
1181 Return TRUE if we are sure they can't be equal, FALSE otherwise.
1182 The whole point of this function is to support cases where either T1 or
1183 T2 is a typedef. In those cases, we need to compare the template parameters
1184 of the _decl_ of the typedef. If those don't match then we know T1
1185 and T2 cannot be equal. */
1188 incompatible_dependent_types_p (tree t1, tree t2)
1190 tree tparms1 = NULL_TREE, tparms2 = NULL_TREE;
1191 bool t1_typedef_variant_p, t2_typedef_variant_p;
1193 if (!uses_template_parms (t1) || !uses_template_parms (t2))
1196 if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM)
1198 /* If T1 and T2 don't have the same relative position in their
1199 template parameters set, they can't be equal. */
1200 if (!comp_template_parms_position (t1, t2))
1204 t1_typedef_variant_p = typedef_variant_p (t1);
1205 t2_typedef_variant_p = typedef_variant_p (t2);
1207 /* Either T1 or T2 must be a typedef. */
1208 if (!t1_typedef_variant_p && !t2_typedef_variant_p)
1211 if (!t1_typedef_variant_p || !t2_typedef_variant_p)
1212 /* Either T1 or T2 is not a typedef so we cannot compare the
1213 the template parms of the typedefs of T1 and T2.
1214 At this point, if the main variant type of T1 and T2 are equal
1215 it means the two types can't be incompatible, from the perspective
1216 of this function. */
1217 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1220 /* So if we reach this point, it means either T1 or T2 is a typedef variant.
1221 Let's compare their template parameters. */
1223 tparms1 = get_template_parms_of_dependent_type (t1);
1224 tparms2 = get_template_parms_of_dependent_type (t2);
1226 /* If T2 is a template type parm and if we could not get the template
1227 parms it belongs to, that means we have not finished parsing the
1228 full set of template parameters of the template declaration it
1229 belongs to yet. If we could get the template parms T1 belongs to,
1230 that mostly means T1 and T2 belongs to templates that are
1231 different and incompatible. */
1232 if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM
1233 && (tparms1 == NULL_TREE || tparms2 == NULL_TREE)
1234 && tparms1 != tparms2)
1237 if (tparms1 == NULL_TREE
1238 || tparms2 == NULL_TREE
1239 || tparms1 == tparms2)
1242 /* And now compare the mighty template parms! */
1243 return !comp_template_parms (tparms1, tparms2);
1246 /* Subroutine in comptypes. */
1249 structural_comptypes (tree t1, tree t2, int strict)
1254 /* Suppress errors caused by previously reported errors. */
1255 if (t1 == error_mark_node || t2 == error_mark_node)
1258 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
1260 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
1261 current instantiation. */
1262 if (TREE_CODE (t1) == TYPENAME_TYPE)
1263 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1265 if (TREE_CODE (t2) == TYPENAME_TYPE)
1266 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1268 if (TYPE_PTRMEMFUNC_P (t1))
1269 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1270 if (TYPE_PTRMEMFUNC_P (t2))
1271 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1273 /* Different classes of types can't be compatible. */
1274 if (TREE_CODE (t1) != TREE_CODE (t2))
1277 /* Qualifiers must match. For array types, we will check when we
1278 recur on the array element types. */
1279 if (TREE_CODE (t1) != ARRAY_TYPE
1280 && cp_type_quals (t1) != cp_type_quals (t2))
1282 if (TREE_CODE (t1) == FUNCTION_TYPE
1283 && type_memfn_quals (t1) != type_memfn_quals (t2))
1285 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1288 /* If T1 and T2 are dependent typedefs then check upfront that
1289 the template parameters of their typedef DECLs match before
1290 going down checking their subtypes. */
1291 if (incompatible_dependent_types_p (t1, t2))
1294 /* Allow for two different type nodes which have essentially the same
1295 definition. Note that we already checked for equality of the type
1296 qualifiers (just above). */
1298 if (TREE_CODE (t1) != ARRAY_TYPE
1299 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1303 /* Compare the types. Break out if they could be the same. */
1304 switch (TREE_CODE (t1))
1308 /* All void and bool types are the same. */
1312 case FIXED_POINT_TYPE:
1314 /* With these nodes, we can't determine type equivalence by
1315 looking at what is stored in the nodes themselves, because
1316 two nodes might have different TYPE_MAIN_VARIANTs but still
1317 represent the same type. For example, wchar_t and int could
1318 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1319 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1320 and are distinct types. On the other hand, int and the
1323 typedef int INT __attribute((may_alias));
1325 have identical properties, different TYPE_MAIN_VARIANTs, but
1326 represent the same type. The canonical type system keeps
1327 track of equivalence in this case, so we fall back on it. */
1328 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1330 case TEMPLATE_TEMPLATE_PARM:
1331 case BOUND_TEMPLATE_TEMPLATE_PARM:
1332 if (!comp_template_parms_position (t1, t2))
1334 if (!comp_template_parms
1335 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1336 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1338 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1340 /* Don't check inheritance. */
1341 strict = COMPARE_STRICT;
1346 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1347 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1348 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1349 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1352 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1354 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1360 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1361 strict & ~COMPARE_REDECLARATION))
1363 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1367 case REFERENCE_TYPE:
1368 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1370 /* fall through to checks for pointer types */
1373 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1374 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1375 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1381 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1383 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1388 /* Target types must match incl. qualifiers. */
1389 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1393 case TEMPLATE_TYPE_PARM:
1394 /* If incompatible_dependent_types_p called earlier didn't decide
1395 T1 and T2 were different, they might be equal. */
1399 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1400 TYPENAME_TYPE_FULLNAME (t2)))
1402 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1406 case UNBOUND_CLASS_TEMPLATE:
1407 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1409 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1414 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1419 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1420 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1424 case TYPE_PACK_EXPANSION:
1425 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1426 PACK_EXPANSION_PATTERN (t2));
1429 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1430 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1431 || (DECLTYPE_FOR_LAMBDA_CAPTURE (t1)
1432 != DECLTYPE_FOR_LAMBDA_CAPTURE (t2))
1433 || (DECLTYPE_FOR_LAMBDA_RETURN (t1)
1434 != DECLTYPE_FOR_LAMBDA_RETURN (t2))
1435 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1436 DECLTYPE_TYPE_EXPR (t2)))
1444 /* If we get here, we know that from a target independent POV the
1445 types are the same. Make sure the target attributes are also
1447 return targetm.comp_type_attributes (t1, t2);
1450 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1451 is a bitwise-or of the COMPARE_* flags. */
1454 comptypes (tree t1, tree t2, int strict)
1456 if (strict == COMPARE_STRICT)
1461 if (t1 == error_mark_node || t2 == error_mark_node)
1464 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1465 /* At least one of the types requires structural equality, so
1466 perform a deep check. */
1467 return structural_comptypes (t1, t2, strict);
1469 #ifdef ENABLE_CHECKING
1470 if (USE_CANONICAL_TYPES)
1472 bool result = structural_comptypes (t1, t2, strict);
1474 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1475 /* The two types are structurally equivalent, but their
1476 canonical types were different. This is a failure of the
1477 canonical type propagation code.*/
1479 ("canonical types differ for identical types %T and %T",
1481 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1482 /* Two types are structurally different, but the canonical
1483 types are the same. This means we were over-eager in
1484 assigning canonical types. */
1486 ("same canonical type node for different types %T and %T",
1492 if (USE_CANONICAL_TYPES)
1493 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1496 return structural_comptypes (t1, t2, strict);
1498 else if (strict == COMPARE_STRUCTURAL)
1499 return structural_comptypes (t1, t2, COMPARE_STRICT);
1501 return structural_comptypes (t1, t2, strict);
1504 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1507 at_least_as_qualified_p (const_tree type1, const_tree type2)
1509 int q1 = cp_type_quals (type1);
1510 int q2 = cp_type_quals (type2);
1512 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1513 return (q1 & q2) == q2;
1516 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1517 more cv-qualified that TYPE1, and 0 otherwise. */
1520 comp_cv_qualification (const_tree type1, const_tree type2)
1522 int q1 = cp_type_quals (type1);
1523 int q2 = cp_type_quals (type2);
1528 if ((q1 & q2) == q2)
1530 else if ((q1 & q2) == q1)
1536 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1537 subset of the cv-qualification signature of TYPE2, and the types
1538 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1541 comp_cv_qual_signature (tree type1, tree type2)
1543 if (comp_ptr_ttypes_real (type2, type1, -1))
1545 else if (comp_ptr_ttypes_real (type1, type2, -1))
1551 /* Subroutines of `comptypes'. */
1553 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1554 equivalent in the sense that functions with those parameter types
1555 can have equivalent types. The two lists must be equivalent,
1556 element by element. */
1559 compparms (const_tree parms1, const_tree parms2)
1563 /* An unspecified parmlist matches any specified parmlist
1564 whose argument types don't need default promotions. */
1566 for (t1 = parms1, t2 = parms2;
1568 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1570 /* If one parmlist is shorter than the other,
1571 they fail to match. */
1574 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1581 /* Process a sizeof or alignof expression where the operand is a
1585 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1590 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1591 if (type == error_mark_node)
1592 return error_mark_node;
1594 type = non_reference (type);
1595 if (TREE_CODE (type) == METHOD_TYPE)
1598 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1599 "invalid application of %qs to a member function",
1600 operator_name_info[(int) op].name);
1601 value = size_one_node;
1604 dependent_p = dependent_type_p (type);
1606 complete_type (type);
1608 /* VLA types will have a non-constant size. In the body of an
1609 uninstantiated template, we don't need to try to compute the
1610 value, because the sizeof expression is not an integral
1611 constant expression in that case. And, if we do try to
1612 compute the value, we'll likely end up with SAVE_EXPRs, which
1613 the template substitution machinery does not expect to see. */
1614 || (processing_template_decl
1615 && COMPLETE_TYPE_P (type)
1616 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1618 value = build_min (op, size_type_node, type);
1619 TREE_READONLY (value) = 1;
1623 return c_sizeof_or_alignof_type (input_location, complete_type (type),
1628 /* Return the size of the type, without producing any warnings for
1629 types whose size cannot be taken. This routine should be used only
1630 in some other routine that has already produced a diagnostic about
1631 using the size of such a type. */
1633 cxx_sizeof_nowarn (tree type)
1635 if (TREE_CODE (type) == FUNCTION_TYPE
1636 || TREE_CODE (type) == VOID_TYPE
1637 || TREE_CODE (type) == ERROR_MARK)
1638 return size_one_node;
1639 else if (!COMPLETE_TYPE_P (type))
1640 return size_zero_node;
1642 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1645 /* Process a sizeof expression where the operand is an expression. */
1648 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1650 if (e == error_mark_node)
1651 return error_mark_node;
1653 if (processing_template_decl)
1655 e = build_min (SIZEOF_EXPR, size_type_node, e);
1656 TREE_SIDE_EFFECTS (e) = 0;
1657 TREE_READONLY (e) = 1;
1662 /* To get the size of a static data member declared as an array of
1663 unknown bound, we need to instantiate it. */
1664 if (TREE_CODE (e) == VAR_DECL
1665 && VAR_HAD_UNKNOWN_BOUND (e)
1666 && DECL_TEMPLATE_INSTANTIATION (e))
1667 instantiate_decl (e, /*defer_ok*/true, /*expl_inst_mem*/false);
1669 e = mark_type_use (e);
1671 if (TREE_CODE (e) == COMPONENT_REF
1672 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1673 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1675 if (complain & tf_error)
1676 error ("invalid application of %<sizeof%> to a bit-field");
1678 return error_mark_node;
1681 else if (is_overloaded_fn (e))
1683 if (complain & tf_error)
1684 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1687 return error_mark_node;
1690 else if (type_unknown_p (e))
1692 if (complain & tf_error)
1693 cxx_incomplete_type_error (e, TREE_TYPE (e));
1695 return error_mark_node;
1701 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1704 /* Implement the __alignof keyword: Return the minimum required
1705 alignment of E, measured in bytes. For VAR_DECL's and
1706 FIELD_DECL's return DECL_ALIGN (which can be set from an
1707 "aligned" __attribute__ specification). */
1710 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1714 if (e == error_mark_node)
1715 return error_mark_node;
1717 if (processing_template_decl)
1719 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1720 TREE_SIDE_EFFECTS (e) = 0;
1721 TREE_READONLY (e) = 1;
1726 e = mark_type_use (e);
1728 if (TREE_CODE (e) == VAR_DECL)
1729 t = size_int (DECL_ALIGN_UNIT (e));
1730 else if (TREE_CODE (e) == COMPONENT_REF
1731 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1732 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1734 if (complain & tf_error)
1735 error ("invalid application of %<__alignof%> to a bit-field");
1737 return error_mark_node;
1740 else if (TREE_CODE (e) == COMPONENT_REF
1741 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1742 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1743 else if (is_overloaded_fn (e))
1745 if (complain & tf_error)
1746 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1749 return error_mark_node;
1750 if (TREE_CODE (e) == FUNCTION_DECL)
1751 t = size_int (DECL_ALIGN_UNIT (e));
1755 else if (type_unknown_p (e))
1757 if (complain & tf_error)
1758 cxx_incomplete_type_error (e, TREE_TYPE (e));
1760 return error_mark_node;
1764 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1765 complain & tf_error);
1767 return fold_convert (size_type_node, t);
1770 /* Process a sizeof or alignof expression E with code OP where the operand
1771 is an expression. */
1774 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1776 if (op == SIZEOF_EXPR)
1777 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1779 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1782 /* EXPR is being used in a context that is not a function call.
1787 The expression can be used only as the left-hand operand of a
1788 member function call.
1790 [expr.mptr.operator]
1792 If the result of .* or ->* is a function, then that result can be
1793 used only as the operand for the function call operator ().
1795 by issuing an error message if appropriate. Returns true iff EXPR
1796 violates these rules. */
1799 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1801 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1803 if (complain & tf_error)
1804 error ("invalid use of non-static member function");
1810 /* If EXP is a reference to a bitfield, and the type of EXP does not
1811 match the declared type of the bitfield, return the declared type
1812 of the bitfield. Otherwise, return NULL_TREE. */
1815 is_bitfield_expr_with_lowered_type (const_tree exp)
1817 switch (TREE_CODE (exp))
1820 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1821 ? TREE_OPERAND (exp, 1)
1822 : TREE_OPERAND (exp, 0)))
1824 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1827 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1831 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1837 field = TREE_OPERAND (exp, 1);
1838 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1840 if (same_type_ignoring_top_level_qualifiers_p
1841 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1843 return DECL_BIT_FIELD_TYPE (field);
1847 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1848 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1849 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1857 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1858 bitfield with a lowered type, the type of EXP is returned, rather
1862 unlowered_expr_type (const_tree exp)
1866 type = is_bitfield_expr_with_lowered_type (exp);
1868 type = TREE_TYPE (exp);
1873 /* Perform the conversions in [expr] that apply when an lvalue appears
1874 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1875 function-to-pointer conversions. In addition, manifest constants
1876 are replaced by their values, and bitfield references are converted
1877 to their declared types. Note that this function does not perform the
1878 lvalue-to-rvalue conversion for class types. If you need that conversion
1879 to for class types, then you probably need to use force_rvalue.
1881 Although the returned value is being used as an rvalue, this
1882 function does not wrap the returned expression in a
1883 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1884 that the return value is no longer an lvalue. */
1887 decay_conversion (tree exp)
1890 enum tree_code code;
1892 type = TREE_TYPE (exp);
1893 if (type == error_mark_node)
1894 return error_mark_node;
1896 exp = mark_rvalue_use (exp);
1898 exp = resolve_nondeduced_context (exp);
1899 if (type_unknown_p (exp))
1901 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1902 return error_mark_node;
1905 exp = decl_constant_value (exp);
1906 if (error_operand_p (exp))
1907 return error_mark_node;
1909 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1910 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1911 code = TREE_CODE (type);
1912 if (code == VOID_TYPE)
1914 error ("void value not ignored as it ought to be");
1915 return error_mark_node;
1917 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1918 return error_mark_node;
1919 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1920 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1921 if (code == ARRAY_TYPE)
1926 if (TREE_CODE (exp) == INDIRECT_REF)
1927 return build_nop (build_pointer_type (TREE_TYPE (type)),
1928 TREE_OPERAND (exp, 0));
1930 if (TREE_CODE (exp) == COMPOUND_EXPR)
1932 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1933 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1934 TREE_OPERAND (exp, 0), op1);
1938 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1940 error ("invalid use of non-lvalue array");
1941 return error_mark_node;
1944 ptrtype = build_pointer_type (TREE_TYPE (type));
1946 if (TREE_CODE (exp) == VAR_DECL)
1948 if (!cxx_mark_addressable (exp))
1949 return error_mark_node;
1950 adr = build_nop (ptrtype, build_address (exp));
1953 /* This way is better for a COMPONENT_REF since it can
1954 simplify the offset for a component. */
1955 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1956 return cp_convert (ptrtype, adr);
1959 /* If a bitfield is used in a context where integral promotion
1960 applies, then the caller is expected to have used
1961 default_conversion. That function promotes bitfields correctly
1962 before calling this function. At this point, if we have a
1963 bitfield referenced, we may assume that is not subject to
1964 promotion, and that, therefore, the type of the resulting rvalue
1965 is the declared type of the bitfield. */
1966 exp = convert_bitfield_to_declared_type (exp);
1968 /* We do not call rvalue() here because we do not want to wrap EXP
1969 in a NON_LVALUE_EXPR. */
1973 Non-class rvalues always have cv-unqualified types. */
1974 type = TREE_TYPE (exp);
1975 if (!CLASS_TYPE_P (type) && cv_qualified_p (type))
1976 exp = build_nop (cv_unqualified (type), exp);
1981 /* Perform preparatory conversions, as part of the "usual arithmetic
1982 conversions". In particular, as per [expr]:
1984 Whenever an lvalue expression appears as an operand of an
1985 operator that expects the rvalue for that operand, the
1986 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1987 standard conversions are applied to convert the expression to an
1990 In addition, we perform integral promotions here, as those are
1991 applied to both operands to a binary operator before determining
1992 what additional conversions should apply. */
1995 default_conversion (tree exp)
1997 /* Check for target-specific promotions. */
1998 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
2000 exp = cp_convert (promoted_type, exp);
2001 /* Perform the integral promotions first so that bitfield
2002 expressions (which may promote to "int", even if the bitfield is
2003 declared "unsigned") are promoted correctly. */
2004 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
2005 exp = perform_integral_promotions (exp);
2006 /* Perform the other conversions. */
2007 exp = decay_conversion (exp);
2012 /* EXPR is an expression with an integral or enumeration type.
2013 Perform the integral promotions in [conv.prom], and return the
2017 perform_integral_promotions (tree expr)
2022 expr = mark_rvalue_use (expr);
2026 If the bitfield has an enumerated type, it is treated as any
2027 other value of that type for promotion purposes. */
2028 type = is_bitfield_expr_with_lowered_type (expr);
2029 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
2030 type = TREE_TYPE (expr);
2031 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
2032 promoted_type = type_promotes_to (type);
2033 if (type != promoted_type)
2034 expr = cp_convert (promoted_type, expr);
2038 /* Returns nonzero iff exp is a STRING_CST or the result of applying
2039 decay_conversion to one. */
2042 string_conv_p (const_tree totype, const_tree exp, int warn)
2046 if (TREE_CODE (totype) != POINTER_TYPE)
2049 t = TREE_TYPE (totype);
2050 if (!same_type_p (t, char_type_node)
2051 && !same_type_p (t, char16_type_node)
2052 && !same_type_p (t, char32_type_node)
2053 && !same_type_p (t, wchar_type_node))
2056 if (TREE_CODE (exp) == STRING_CST)
2058 /* Make sure that we don't try to convert between char and wide chars. */
2059 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
2064 /* Is this a string constant which has decayed to 'const char *'? */
2065 t = build_pointer_type (cp_build_qualified_type (t, TYPE_QUAL_CONST));
2066 if (!same_type_p (TREE_TYPE (exp), t))
2069 if (TREE_CODE (exp) != ADDR_EXPR
2070 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
2074 /* This warning is not very useful, as it complains about printf. */
2076 warning (OPT_Wwrite_strings,
2077 "deprecated conversion from string constant to %qT",
2083 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
2084 can, for example, use as an lvalue. This code used to be in
2085 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
2086 expressions, where we're dealing with aggregates. But now it's again only
2087 called from unary_complex_lvalue. The case (in particular) that led to
2088 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
2092 rationalize_conditional_expr (enum tree_code code, tree t,
2093 tsubst_flags_t complain)
2095 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
2096 the first operand is always the one to be used if both operands
2097 are equal, so we know what conditional expression this used to be. */
2098 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
2100 tree op0 = TREE_OPERAND (t, 0);
2101 tree op1 = TREE_OPERAND (t, 1);
2103 /* The following code is incorrect if either operand side-effects. */
2104 gcc_assert (!TREE_SIDE_EFFECTS (op0)
2105 && !TREE_SIDE_EFFECTS (op1));
2107 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
2108 ? LE_EXPR : GE_EXPR),
2109 op0, TREE_CODE (op0),
2110 op1, TREE_CODE (op1),
2111 /*overloaded_p=*/NULL,
2113 cp_build_unary_op (code, op0, 0, complain),
2114 cp_build_unary_op (code, op1, 0, complain),
2119 build_conditional_expr (TREE_OPERAND (t, 0),
2120 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
2122 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
2127 /* Given the TYPE of an anonymous union field inside T, return the
2128 FIELD_DECL for the field. If not found return NULL_TREE. Because
2129 anonymous unions can nest, we must also search all anonymous unions
2130 that are directly reachable. */
2133 lookup_anon_field (tree t, tree type)
2137 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2139 if (TREE_STATIC (field))
2141 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
2144 /* If we find it directly, return the field. */
2145 if (DECL_NAME (field) == NULL_TREE
2146 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
2151 /* Otherwise, it could be nested, search harder. */
2152 if (DECL_NAME (field) == NULL_TREE
2153 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2155 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
2163 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
2164 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
2165 non-NULL, it indicates the path to the base used to name MEMBER.
2166 If PRESERVE_REFERENCE is true, the expression returned will have
2167 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
2168 returned will have the type referred to by the reference.
2170 This function does not perform access control; that is either done
2171 earlier by the parser when the name of MEMBER is resolved to MEMBER
2172 itself, or later when overload resolution selects one of the
2173 functions indicated by MEMBER. */
2176 build_class_member_access_expr (tree object, tree member,
2177 tree access_path, bool preserve_reference,
2178 tsubst_flags_t complain)
2182 tree result = NULL_TREE;
2184 if (error_operand_p (object) || error_operand_p (member))
2185 return error_mark_node;
2187 gcc_assert (DECL_P (member) || BASELINK_P (member));
2191 The type of the first expression shall be "class object" (of a
2193 object_type = TREE_TYPE (object);
2194 if (!currently_open_class (object_type)
2195 && !complete_type_or_else (object_type, object))
2196 return error_mark_node;
2197 if (!CLASS_TYPE_P (object_type))
2199 if (complain & tf_error)
2200 error ("request for member %qD in %qE, which is of non-class type %qT",
2201 member, object, object_type);
2202 return error_mark_node;
2205 /* The standard does not seem to actually say that MEMBER must be a
2206 member of OBJECT_TYPE. However, that is clearly what is
2208 if (DECL_P (member))
2210 member_scope = DECL_CLASS_CONTEXT (member);
2212 if (TREE_DEPRECATED (member))
2213 warn_deprecated_use (member, NULL_TREE);
2216 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
2217 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
2218 presently be the anonymous union. Go outwards until we find a
2219 type related to OBJECT_TYPE. */
2220 while (ANON_AGGR_TYPE_P (member_scope)
2221 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
2223 member_scope = TYPE_CONTEXT (member_scope);
2224 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
2226 if (complain & tf_error)
2228 if (TREE_CODE (member) == FIELD_DECL)
2229 error ("invalid use of nonstatic data member %qE", member);
2231 error ("%qD is not a member of %qT", member, object_type);
2233 return error_mark_node;
2236 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
2237 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
2238 in the front end; only _DECLs and _REFs are lvalues in the back end. */
2240 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
2242 object = cp_build_indirect_ref (temp, RO_NULL, complain);
2245 /* In [expr.ref], there is an explicit list of the valid choices for
2246 MEMBER. We check for each of those cases here. */
2247 if (TREE_CODE (member) == VAR_DECL)
2249 /* A static data member. */
2251 mark_exp_read (object);
2252 /* If OBJECT has side-effects, they are supposed to occur. */
2253 if (TREE_SIDE_EFFECTS (object))
2254 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
2256 else if (TREE_CODE (member) == FIELD_DECL)
2258 /* A non-static data member. */
2263 null_object_p = (TREE_CODE (object) == INDIRECT_REF
2264 && integer_zerop (TREE_OPERAND (object, 0)));
2266 /* Convert OBJECT to the type of MEMBER. */
2267 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
2268 TYPE_MAIN_VARIANT (member_scope)))
2273 binfo = lookup_base (access_path ? access_path : object_type,
2274 member_scope, ba_unique, &kind);
2275 if (binfo == error_mark_node)
2276 return error_mark_node;
2278 /* It is invalid to try to get to a virtual base of a
2279 NULL object. The most common cause is invalid use of
2281 if (null_object_p && kind == bk_via_virtual)
2283 if (complain & tf_error)
2285 error ("invalid access to non-static data member %qD of "
2288 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
2290 return error_mark_node;
2293 /* Convert to the base. */
2294 object = build_base_path (PLUS_EXPR, object, binfo,
2296 /* If we found the base successfully then we should be able
2297 to convert to it successfully. */
2298 gcc_assert (object != error_mark_node);
2301 /* Complain about other invalid uses of offsetof, even though they will
2302 give the right answer. Note that we complain whether or not they
2303 actually used the offsetof macro, since there's no way to know at this
2304 point. So we just give a warning, instead of a pedwarn. */
2305 /* Do not produce this warning for base class field references, because
2306 we know for a fact that didn't come from offsetof. This does occur
2307 in various testsuite cases where a null object is passed where a
2308 vtable access is required. */
2309 if (null_object_p && warn_invalid_offsetof
2310 && CLASSTYPE_NON_STD_LAYOUT (object_type)
2311 && !DECL_FIELD_IS_BASE (member)
2312 && cp_unevaluated_operand == 0
2313 && (complain & tf_warning))
2315 warning (OPT_Winvalid_offsetof,
2316 "invalid access to non-static data member %qD "
2317 " of NULL object", member);
2318 warning (OPT_Winvalid_offsetof,
2319 "(perhaps the %<offsetof%> macro was used incorrectly)");
2322 /* If MEMBER is from an anonymous aggregate, we have converted
2323 OBJECT so that it refers to the class containing the
2324 anonymous union. Generate a reference to the anonymous union
2325 itself, and recur to find MEMBER. */
2326 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2327 /* When this code is called from build_field_call, the
2328 object already has the type of the anonymous union.
2329 That is because the COMPONENT_REF was already
2330 constructed, and was then disassembled before calling
2331 build_field_call. After the function-call code is
2332 cleaned up, this waste can be eliminated. */
2333 && (!same_type_ignoring_top_level_qualifiers_p
2334 (TREE_TYPE (object), DECL_CONTEXT (member))))
2336 tree anonymous_union;
2338 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2339 DECL_CONTEXT (member));
2340 object = build_class_member_access_expr (object,
2342 /*access_path=*/NULL_TREE,
2347 /* Compute the type of the field, as described in [expr.ref]. */
2348 type_quals = TYPE_UNQUALIFIED;
2349 member_type = TREE_TYPE (member);
2350 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2352 type_quals = (cp_type_quals (member_type)
2353 | cp_type_quals (object_type));
2355 /* A field is const (volatile) if the enclosing object, or the
2356 field itself, is const (volatile). But, a mutable field is
2357 not const, even within a const object. */
2358 if (DECL_MUTABLE_P (member))
2359 type_quals &= ~TYPE_QUAL_CONST;
2360 member_type = cp_build_qualified_type (member_type, type_quals);
2363 result = build3 (COMPONENT_REF, member_type, object, member,
2365 result = fold_if_not_in_template (result);
2367 /* Mark the expression const or volatile, as appropriate. Even
2368 though we've dealt with the type above, we still have to mark the
2369 expression itself. */
2370 if (type_quals & TYPE_QUAL_CONST)
2371 TREE_READONLY (result) = 1;
2372 if (type_quals & TYPE_QUAL_VOLATILE)
2373 TREE_THIS_VOLATILE (result) = 1;
2375 else if (BASELINK_P (member))
2377 /* The member is a (possibly overloaded) member function. */
2381 /* If the MEMBER is exactly one static member function, then we
2382 know the type of the expression. Otherwise, we must wait
2383 until overload resolution has been performed. */
2384 functions = BASELINK_FUNCTIONS (member);
2385 if (TREE_CODE (functions) == FUNCTION_DECL
2386 && DECL_STATIC_FUNCTION_P (functions))
2387 type = TREE_TYPE (functions);
2389 type = unknown_type_node;
2390 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2391 base. That will happen when the function is called. */
2392 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2394 else if (TREE_CODE (member) == CONST_DECL)
2396 /* The member is an enumerator. */
2398 /* If OBJECT has side-effects, they are supposed to occur. */
2399 if (TREE_SIDE_EFFECTS (object))
2400 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2405 if (complain & tf_error)
2406 error ("invalid use of %qD", member);
2407 return error_mark_node;
2410 if (!preserve_reference)
2413 If E2 is declared to have type "reference to T", then ... the
2414 type of E1.E2 is T. */
2415 result = convert_from_reference (result);
2420 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2421 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2424 lookup_destructor (tree object, tree scope, tree dtor_name)
2426 tree object_type = TREE_TYPE (object);
2427 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2430 if (scope && !check_dtor_name (scope, dtor_type))
2432 error ("qualified type %qT does not match destructor name ~%qT",
2434 return error_mark_node;
2436 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2438 /* In a template, names we can't find a match for are still accepted
2439 destructor names, and we check them here. */
2440 if (check_dtor_name (object_type, dtor_type))
2441 dtor_type = object_type;
2444 error ("object type %qT does not match destructor name ~%qT",
2445 object_type, dtor_type);
2446 return error_mark_node;
2450 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2452 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2453 TYPE_MAIN_VARIANT (object_type), dtor_type);
2454 return error_mark_node;
2456 expr = lookup_member (dtor_type, complete_dtor_identifier,
2457 /*protect=*/1, /*want_type=*/false);
2458 expr = (adjust_result_of_qualified_name_lookup
2459 (expr, dtor_type, object_type));
2463 /* An expression of the form "A::template B" has been resolved to
2464 DECL. Issue a diagnostic if B is not a template or template
2468 check_template_keyword (tree decl)
2470 /* The standard says:
2474 If a name prefixed by the keyword template is not a member
2475 template, the program is ill-formed.
2477 DR 228 removed the restriction that the template be a member
2480 DR 96, if accepted would add the further restriction that explicit
2481 template arguments must be provided if the template keyword is
2482 used, but, as of 2005-10-16, that DR is still in "drafting". If
2483 this DR is accepted, then the semantic checks here can be
2484 simplified, as the entity named must in fact be a template
2485 specialization, rather than, as at present, a set of overloaded
2486 functions containing at least one template function. */
2487 if (TREE_CODE (decl) != TEMPLATE_DECL
2488 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2490 if (!is_overloaded_fn (decl))
2491 permerror (input_location, "%qD is not a template", decl);
2496 if (BASELINK_P (fns))
2497 fns = BASELINK_FUNCTIONS (fns);
2500 tree fn = OVL_CURRENT (fns);
2501 if (TREE_CODE (fn) == TEMPLATE_DECL
2502 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2504 if (TREE_CODE (fn) == FUNCTION_DECL
2505 && DECL_USE_TEMPLATE (fn)
2506 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2508 fns = OVL_NEXT (fns);
2511 permerror (input_location, "%qD is not a template", decl);
2516 /* This function is called by the parser to process a class member
2517 access expression of the form OBJECT.NAME. NAME is a node used by
2518 the parser to represent a name; it is not yet a DECL. It may,
2519 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2520 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2521 there is no reason to do the lookup twice, so the parser keeps the
2522 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2523 be a template via the use of the "A::template B" syntax. */
2526 finish_class_member_access_expr (tree object, tree name, bool template_p,
2527 tsubst_flags_t complain)
2532 tree access_path = NULL_TREE;
2533 tree orig_object = object;
2534 tree orig_name = name;
2536 if (object == error_mark_node || name == error_mark_node)
2537 return error_mark_node;
2539 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2540 if (!objc_is_public (object, name))
2541 return error_mark_node;
2543 object_type = TREE_TYPE (object);
2545 if (processing_template_decl)
2547 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2548 dependent_type_p (object_type)
2549 /* If NAME is just an IDENTIFIER_NODE, then the expression
2551 || TREE_CODE (object) == IDENTIFIER_NODE
2552 /* If NAME is "f<args>", where either 'f' or 'args' is
2553 dependent, then the expression is dependent. */
2554 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2555 && dependent_template_id_p (TREE_OPERAND (name, 0),
2556 TREE_OPERAND (name, 1)))
2557 /* If NAME is "T::X" where "T" is dependent, then the
2558 expression is dependent. */
2559 || (TREE_CODE (name) == SCOPE_REF
2560 && TYPE_P (TREE_OPERAND (name, 0))
2561 && dependent_type_p (TREE_OPERAND (name, 0))))
2562 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2563 object = build_non_dependent_expr (object);
2568 The type of the first expression shall be "class object" (of a
2570 if (!currently_open_class (object_type)
2571 && !complete_type_or_else (object_type, object))
2572 return error_mark_node;
2573 if (!CLASS_TYPE_P (object_type))
2575 if (complain & tf_error)
2576 error ("request for member %qD in %qE, which is of non-class type %qT",
2577 name, object, object_type);
2578 return error_mark_node;
2581 if (BASELINK_P (name))
2582 /* A member function that has already been looked up. */
2586 bool is_template_id = false;
2587 tree template_args = NULL_TREE;
2590 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2592 is_template_id = true;
2593 template_args = TREE_OPERAND (name, 1);
2594 name = TREE_OPERAND (name, 0);
2596 if (TREE_CODE (name) == OVERLOAD)
2597 name = DECL_NAME (get_first_fn (name));
2598 else if (DECL_P (name))
2599 name = DECL_NAME (name);
2602 if (TREE_CODE (name) == SCOPE_REF)
2604 /* A qualified name. The qualifying class or namespace `S'
2605 has already been looked up; it is either a TYPE or a
2607 scope = TREE_OPERAND (name, 0);
2608 name = TREE_OPERAND (name, 1);
2610 /* If SCOPE is a namespace, then the qualified name does not
2611 name a member of OBJECT_TYPE. */
2612 if (TREE_CODE (scope) == NAMESPACE_DECL)
2614 if (complain & tf_error)
2615 error ("%<%D::%D%> is not a member of %qT",
2616 scope, name, object_type);
2617 return error_mark_node;
2620 gcc_assert (CLASS_TYPE_P (scope));
2621 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2622 || TREE_CODE (name) == BIT_NOT_EXPR);
2624 if (constructor_name_p (name, scope))
2626 if (complain & tf_error)
2627 error ("cannot call constructor %<%T::%D%> directly",
2629 return error_mark_node;
2632 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2633 access_path = lookup_base (object_type, scope, ba_check, NULL);
2634 if (access_path == error_mark_node)
2635 return error_mark_node;
2638 if (complain & tf_error)
2639 error ("%qT is not a base of %qT", scope, object_type);
2640 return error_mark_node;
2646 access_path = object_type;
2649 if (TREE_CODE (name) == BIT_NOT_EXPR)
2650 member = lookup_destructor (object, scope, name);
2653 /* Look up the member. */
2654 member = lookup_member (access_path, name, /*protect=*/1,
2655 /*want_type=*/false);
2656 if (member == NULL_TREE)
2658 if (complain & tf_error)
2659 error ("%qD has no member named %qE", object_type, name);
2660 return error_mark_node;
2662 if (member == error_mark_node)
2663 return error_mark_node;
2668 tree templ = member;
2670 if (BASELINK_P (templ))
2671 templ = lookup_template_function (templ, template_args);
2674 if (complain & tf_error)
2675 error ("%qD is not a member template function", name);
2676 return error_mark_node;
2681 if (TREE_DEPRECATED (member))
2682 warn_deprecated_use (member, NULL_TREE);
2685 check_template_keyword (member);
2687 expr = build_class_member_access_expr (object, member, access_path,
2688 /*preserve_reference=*/false,
2690 if (processing_template_decl && expr != error_mark_node)
2692 if (BASELINK_P (member))
2694 if (TREE_CODE (orig_name) == SCOPE_REF)
2695 BASELINK_QUALIFIED_P (member) = 1;
2698 return build_min_non_dep (COMPONENT_REF, expr,
2699 orig_object, orig_name,
2706 /* Return an expression for the MEMBER_NAME field in the internal
2707 representation of PTRMEM, a pointer-to-member function. (Each
2708 pointer-to-member function type gets its own RECORD_TYPE so it is
2709 more convenient to access the fields by name than by FIELD_DECL.)
2710 This routine converts the NAME to a FIELD_DECL and then creates the
2711 node for the complete expression. */
2714 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2720 /* This code is a stripped down version of
2721 build_class_member_access_expr. It does not work to use that
2722 routine directly because it expects the object to be of class
2724 ptrmem_type = TREE_TYPE (ptrmem);
2725 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2726 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2727 /*want_type=*/false);
2728 member_type = cp_build_qualified_type (TREE_TYPE (member),
2729 cp_type_quals (ptrmem_type));
2730 return fold_build3_loc (input_location,
2731 COMPONENT_REF, member_type,
2732 ptrmem, member, NULL_TREE);
2735 /* Given an expression PTR for a pointer, return an expression
2736 for the value pointed to.
2737 ERRORSTRING is the name of the operator to appear in error messages.
2739 This function may need to overload OPERATOR_FNNAME.
2740 Must also handle REFERENCE_TYPEs for C++. */
2743 build_x_indirect_ref (tree expr, ref_operator errorstring,
2744 tsubst_flags_t complain)
2746 tree orig_expr = expr;
2749 if (processing_template_decl)
2751 /* Retain the type if we know the operand is a pointer so that
2752 describable_type doesn't make auto deduction break. */
2753 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
2754 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
2755 if (type_dependent_expression_p (expr))
2756 return build_min_nt (INDIRECT_REF, expr);
2757 expr = build_non_dependent_expr (expr);
2760 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2761 NULL_TREE, /*overloaded_p=*/NULL, complain);
2763 rval = cp_build_indirect_ref (expr, errorstring, complain);
2765 if (processing_template_decl && rval != error_mark_node)
2766 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2771 /* Helper function called from c-common. */
2773 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2774 tree ptr, ref_operator errorstring)
2776 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2780 cp_build_indirect_ref (tree ptr, ref_operator errorstring,
2781 tsubst_flags_t complain)
2785 if (ptr == error_mark_node)
2786 return error_mark_node;
2788 if (ptr == current_class_ptr)
2789 return current_class_ref;
2791 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2792 ? ptr : decay_conversion (ptr));
2793 type = TREE_TYPE (pointer);
2795 if (POINTER_TYPE_P (type))
2799 If the type of the expression is "pointer to T," the type
2800 of the result is "T." */
2801 tree t = TREE_TYPE (type);
2803 if (CONVERT_EXPR_P (ptr)
2804 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2806 /* If a warning is issued, mark it to avoid duplicates from
2807 the backend. This only needs to be done at
2808 warn_strict_aliasing > 2. */
2809 if (warn_strict_aliasing > 2)
2810 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2811 type, TREE_OPERAND (ptr, 0)))
2812 TREE_NO_WARNING (ptr) = 1;
2815 if (VOID_TYPE_P (t))
2817 /* A pointer to incomplete type (other than cv void) can be
2818 dereferenced [expr.unary.op]/1 */
2819 if (complain & tf_error)
2820 error ("%qT is not a pointer-to-object type", type);
2821 return error_mark_node;
2823 else if (TREE_CODE (pointer) == ADDR_EXPR
2824 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2825 /* The POINTER was something like `&x'. We simplify `*&x' to
2827 return TREE_OPERAND (pointer, 0);
2830 tree ref = build1 (INDIRECT_REF, t, pointer);
2832 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2833 so that we get the proper error message if the result is used
2834 to assign to. Also, &* is supposed to be a no-op. */
2835 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2836 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2837 TREE_SIDE_EFFECTS (ref)
2838 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2842 else if (!(complain & tf_error))
2843 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2845 /* `pointer' won't be an error_mark_node if we were given a
2846 pointer to member, so it's cool to check for this here. */
2847 else if (TYPE_PTR_TO_MEMBER_P (type))
2848 switch (errorstring)
2850 case RO_ARRAY_INDEXING:
2851 error ("invalid use of array indexing on pointer to member");
2854 error ("invalid use of unary %<*%> on pointer to member");
2856 case RO_IMPLICIT_CONVERSION:
2857 error ("invalid use of implicit conversion on pointer to member");
2862 else if (pointer != error_mark_node)
2863 switch (errorstring)
2866 error ("invalid type argument");
2868 case RO_ARRAY_INDEXING:
2869 error ("invalid type argument of array indexing");
2872 error ("invalid type argument of unary %<*%>");
2874 case RO_IMPLICIT_CONVERSION:
2875 error ("invalid type argument of implicit conversion");
2880 return error_mark_node;
2883 /* This handles expressions of the form "a[i]", which denotes
2886 This is logically equivalent in C to *(a+i), but we may do it differently.
2887 If A is a variable or a member, we generate a primitive ARRAY_REF.
2888 This avoids forcing the array out of registers, and can work on
2889 arrays that are not lvalues (for example, members of structures returned
2892 If INDEX is of some user-defined type, it must be converted to
2893 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2894 will inherit the type of the array, which will be some pointer type.
2896 LOC is the location to use in building the array reference. */
2899 cp_build_array_ref (location_t loc, tree array, tree idx,
2900 tsubst_flags_t complain)
2906 if (complain & tf_error)
2907 error_at (loc, "subscript missing in array reference");
2908 return error_mark_node;
2911 if (TREE_TYPE (array) == error_mark_node
2912 || TREE_TYPE (idx) == error_mark_node)
2913 return error_mark_node;
2915 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2917 switch (TREE_CODE (array))
2921 tree value = cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
2923 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2924 TREE_OPERAND (array, 0), value);
2925 SET_EXPR_LOCATION (ret, loc);
2930 ret = build_conditional_expr
2931 (TREE_OPERAND (array, 0),
2932 cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
2934 cp_build_array_ref (loc, TREE_OPERAND (array, 2), idx,
2936 tf_warning_or_error);
2937 protected_set_expr_location (ret, loc);
2944 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2948 warn_array_subscript_with_type_char (idx);
2950 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2952 if (complain & tf_error)
2953 error_at (loc, "array subscript is not an integer");
2954 return error_mark_node;
2957 /* Apply integral promotions *after* noticing character types.
2958 (It is unclear why we do these promotions -- the standard
2959 does not say that we should. In fact, the natural thing would
2960 seem to be to convert IDX to ptrdiff_t; we're performing
2961 pointer arithmetic.) */
2962 idx = perform_integral_promotions (idx);
2964 /* An array that is indexed by a non-constant
2965 cannot be stored in a register; we must be able to do
2966 address arithmetic on its address.
2967 Likewise an array of elements of variable size. */
2968 if (TREE_CODE (idx) != INTEGER_CST
2969 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2970 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2973 if (!cxx_mark_addressable (array))
2974 return error_mark_node;
2977 /* An array that is indexed by a constant value which is not within
2978 the array bounds cannot be stored in a register either; because we
2979 would get a crash in store_bit_field/extract_bit_field when trying
2980 to access a non-existent part of the register. */
2981 if (TREE_CODE (idx) == INTEGER_CST
2982 && TYPE_DOMAIN (TREE_TYPE (array))
2983 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2985 if (!cxx_mark_addressable (array))
2986 return error_mark_node;
2989 if (!lvalue_p (array) && (complain & tf_error))
2990 pedwarn (loc, OPT_pedantic,
2991 "ISO C++ forbids subscripting non-lvalue array");
2993 /* Note in C++ it is valid to subscript a `register' array, since
2994 it is valid to take the address of something with that
2995 storage specification. */
2999 while (TREE_CODE (foo) == COMPONENT_REF)
3000 foo = TREE_OPERAND (foo, 0);
3001 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo)
3002 && (complain & tf_warning))
3003 warning_at (loc, OPT_Wextra,
3004 "subscripting array declared %<register%>");
3007 type = TREE_TYPE (TREE_TYPE (array));
3008 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
3009 /* Array ref is const/volatile if the array elements are
3010 or if the array is.. */
3011 TREE_READONLY (rval)
3012 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
3013 TREE_SIDE_EFFECTS (rval)
3014 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
3015 TREE_THIS_VOLATILE (rval)
3016 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
3017 ret = require_complete_type (fold_if_not_in_template (rval));
3018 protected_set_expr_location (ret, loc);
3023 tree ar = default_conversion (array);
3024 tree ind = default_conversion (idx);
3026 /* Put the integer in IND to simplify error checking. */
3027 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
3034 if (ar == error_mark_node)
3037 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
3039 if (complain & tf_error)
3040 error_at (loc, "subscripted value is neither array nor pointer");
3041 return error_mark_node;
3043 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
3045 if (complain & tf_error)
3046 error_at (loc, "array subscript is not an integer");
3047 return error_mark_node;
3050 warn_array_subscript_with_type_char (idx);
3052 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
3057 protected_set_expr_location (ret, loc);
3062 /* Entry point for Obj-C++. */
3065 build_array_ref (location_t loc, tree array, tree idx)
3067 return cp_build_array_ref (loc, array, idx, tf_warning_or_error);
3070 /* Resolve a pointer to member function. INSTANCE is the object
3071 instance to use, if the member points to a virtual member.
3073 This used to avoid checking for virtual functions if basetype
3074 has no virtual functions, according to an earlier ANSI draft.
3075 With the final ISO C++ rules, such an optimization is
3076 incorrect: A pointer to a derived member can be static_cast
3077 to pointer-to-base-member, as long as the dynamic object
3078 later has the right member. */
3081 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
3083 if (TREE_CODE (function) == OFFSET_REF)
3084 function = TREE_OPERAND (function, 1);
3086 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
3088 tree idx, delta, e1, e2, e3, vtbl, basetype;
3089 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
3091 tree instance_ptr = *instance_ptrptr;
3092 tree instance_save_expr = 0;
3093 if (instance_ptr == error_mark_node)
3095 if (TREE_CODE (function) == PTRMEM_CST)
3097 /* Extracting the function address from a pmf is only
3098 allowed with -Wno-pmf-conversions. It only works for
3100 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
3101 e1 = convert (fntype, e1);
3106 error ("object missing in use of %qE", function);
3107 return error_mark_node;
3111 if (TREE_SIDE_EFFECTS (instance_ptr))
3112 instance_ptr = instance_save_expr = save_expr (instance_ptr);
3114 if (TREE_SIDE_EFFECTS (function))
3115 function = save_expr (function);
3117 /* Start by extracting all the information from the PMF itself. */
3118 e3 = pfn_from_ptrmemfunc (function);
3119 delta = delta_from_ptrmemfunc (function);
3120 idx = build1 (NOP_EXPR, vtable_index_type, e3);
3121 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
3123 case ptrmemfunc_vbit_in_pfn:
3124 e1 = cp_build_binary_op (input_location,
3125 BIT_AND_EXPR, idx, integer_one_node,
3126 tf_warning_or_error);
3127 idx = cp_build_binary_op (input_location,
3128 MINUS_EXPR, idx, integer_one_node,
3129 tf_warning_or_error);
3132 case ptrmemfunc_vbit_in_delta:
3133 e1 = cp_build_binary_op (input_location,
3134 BIT_AND_EXPR, delta, integer_one_node,
3135 tf_warning_or_error);
3136 delta = cp_build_binary_op (input_location,
3137 RSHIFT_EXPR, delta, integer_one_node,
3138 tf_warning_or_error);
3145 /* Convert down to the right base before using the instance. A
3146 special case is that in a pointer to member of class C, C may
3147 be incomplete. In that case, the function will of course be
3148 a member of C, and no conversion is required. In fact,
3149 lookup_base will fail in that case, because incomplete
3150 classes do not have BINFOs. */
3151 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
3152 if (!same_type_ignoring_top_level_qualifiers_p
3153 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
3155 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
3156 basetype, ba_check, NULL);
3157 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
3159 if (instance_ptr == error_mark_node)
3160 return error_mark_node;
3162 /* ...and then the delta in the PMF. */
3163 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
3164 instance_ptr, fold_convert (sizetype, delta));
3166 /* Hand back the adjusted 'this' argument to our caller. */
3167 *instance_ptrptr = instance_ptr;
3169 /* Next extract the vtable pointer from the object. */
3170 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
3172 vtbl = cp_build_indirect_ref (vtbl, RO_NULL, tf_warning_or_error);
3173 /* If the object is not dynamic the access invokes undefined
3174 behavior. As it is not executed in this case silence the
3175 spurious warnings it may provoke. */
3176 TREE_NO_WARNING (vtbl) = 1;
3178 /* Finally, extract the function pointer from the vtable. */
3179 e2 = fold_build2_loc (input_location,
3180 POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
3181 fold_convert (sizetype, idx));
3182 e2 = cp_build_indirect_ref (e2, RO_NULL, tf_warning_or_error);
3183 TREE_CONSTANT (e2) = 1;
3185 /* When using function descriptors, the address of the
3186 vtable entry is treated as a function pointer. */
3187 if (TARGET_VTABLE_USES_DESCRIPTORS)
3188 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
3189 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
3190 tf_warning_or_error));
3192 e2 = fold_convert (TREE_TYPE (e3), e2);
3193 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
3195 /* Make sure this doesn't get evaluated first inside one of the
3196 branches of the COND_EXPR. */
3197 if (instance_save_expr)
3198 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
3199 instance_save_expr, e1);
3206 /* Used by the C-common bits. */
3208 build_function_call (location_t loc ATTRIBUTE_UNUSED,
3209 tree function, tree params)
3211 return cp_build_function_call (function, params, tf_warning_or_error);
3214 /* Used by the C-common bits. */
3216 build_function_call_vec (location_t loc ATTRIBUTE_UNUSED,
3217 tree function, VEC(tree,gc) *params,
3218 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
3220 VEC(tree,gc) *orig_params = params;
3221 tree ret = cp_build_function_call_vec (function, ¶ms,
3222 tf_warning_or_error);
3224 /* cp_build_function_call_vec can reallocate PARAMS by adding
3225 default arguments. That should never happen here. Verify
3227 gcc_assert (params == orig_params);
3232 /* Build a function call using a tree list of arguments. */
3235 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
3240 vec = make_tree_vector ();
3241 for (; params != NULL_TREE; params = TREE_CHAIN (params))
3242 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
3243 ret = cp_build_function_call_vec (function, &vec, complain);
3244 release_tree_vector (vec);
3248 /* Build a function call using varargs. */
3251 cp_build_function_call_nary (tree function, tsubst_flags_t complain, ...)
3257 vec = make_tree_vector ();
3258 va_start (args, complain);
3259 for (t = va_arg (args, tree); t != NULL_TREE; t = va_arg (args, tree))
3260 VEC_safe_push (tree, gc, vec, t);
3262 ret = cp_build_function_call_vec (function, &vec, complain);
3263 release_tree_vector (vec);
3267 /* Build a function call using a vector of arguments. PARAMS may be
3268 NULL if there are no parameters. This changes the contents of
3272 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
3273 tsubst_flags_t complain)
3275 tree fntype, fndecl;
3277 tree original = function;
3281 VEC(tree,gc) *allocated = NULL;
3284 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
3285 expressions, like those used for ObjC messenger dispatches. */
3286 if (params != NULL && !VEC_empty (tree, *params))
3287 function = objc_rewrite_function_call (function,
3288 VEC_index (tree, *params, 0));
3290 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3291 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
3292 if (TREE_CODE (function) == NOP_EXPR
3293 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
3294 function = TREE_OPERAND (function, 0);
3296 if (TREE_CODE (function) == FUNCTION_DECL)
3298 mark_used (function);
3301 /* Convert anything with function type to a pointer-to-function. */
3302 if (DECL_MAIN_P (function) && (complain & tf_error))
3303 pedwarn (input_location, OPT_pedantic,
3304 "ISO C++ forbids calling %<::main%> from within program");
3306 function = build_addr_func (function);
3312 function = build_addr_func (function);
3315 if (function == error_mark_node)
3316 return error_mark_node;
3318 fntype = TREE_TYPE (function);
3320 if (TYPE_PTRMEMFUNC_P (fntype))
3322 if (complain & tf_error)
3323 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
3324 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
3325 original, original);
3326 return error_mark_node;
3329 is_method = (TREE_CODE (fntype) == POINTER_TYPE
3330 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
3332 if (!((TREE_CODE (fntype) == POINTER_TYPE
3333 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
3335 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
3337 if (complain & tf_error)
3338 error ("%qE cannot be used as a function", original);
3339 return error_mark_node;
3342 /* fntype now gets the type of function pointed to. */
3343 fntype = TREE_TYPE (fntype);
3344 parm_types = TYPE_ARG_TYPES (fntype);
3348 allocated = make_tree_vector ();
3349 params = &allocated;
3352 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
3355 return error_mark_node;
3357 argarray = VEC_address (tree, *params);
3359 /* Check for errors in format strings and inappropriately
3361 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
3364 ret = build_cxx_call (function, nargs, argarray);
3366 if (allocated != NULL)
3367 release_tree_vector (allocated);
3372 /* Subroutine of convert_arguments.
3373 Warn about wrong number of args are genereted. */
3376 warn_args_num (location_t loc, tree fndecl, bool too_many_p)
3380 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3382 if (DECL_NAME (fndecl) == NULL_TREE
3383 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3386 ? G_("too many arguments to constructor %q#D")
3387 : G_("too few arguments to constructor %q#D"),
3392 ? G_("too many arguments to member function %q#D")
3393 : G_("too few arguments to member function %q#D"),
3399 ? G_("too many arguments to function %q#D")
3400 : G_("too few arguments to function %q#D"),
3402 inform (DECL_SOURCE_LOCATION (fndecl),
3406 error_at (loc, too_many_p ? G_("too many arguments to function")
3407 : G_("too few arguments to function"));
3410 /* Convert the actual parameter expressions in the list VALUES to the
3411 types in the list TYPELIST. The converted expressions are stored
3412 back in the VALUES vector.
3413 If parmdecls is exhausted, or when an element has NULL as its type,
3414 perform the default conversions.
3416 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3418 This is also where warnings about wrong number of args are generated.
3420 Returns the actual number of arguments processed (which might be less
3421 than the length of the vector), or -1 on error.
3423 In C++, unspecified trailing parameters can be filled in with their
3424 default arguments, if such were specified. Do so here. */
3427 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3428 int flags, tsubst_flags_t complain)
3433 /* Argument passing is always copy-initialization. */
3434 flags |= LOOKUP_ONLYCONVERTING;
3436 for (i = 0, typetail = typelist;
3437 i < VEC_length (tree, *values);
3440 tree type = typetail ? TREE_VALUE (typetail) : 0;
3441 tree val = VEC_index (tree, *values, i);
3443 if (val == error_mark_node || type == error_mark_node)
3446 if (type == void_type_node)
3448 if (complain & tf_error)
3450 warn_args_num (input_location, fndecl, /*too_many_p=*/true);
3457 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3458 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3459 if (TREE_CODE (val) == NOP_EXPR
3460 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3461 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3462 val = TREE_OPERAND (val, 0);
3464 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3466 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3467 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3468 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3469 val = decay_conversion (val);
3472 if (val == error_mark_node)
3477 /* Formal parm type is specified by a function prototype. */
3480 if (!COMPLETE_TYPE_P (complete_type (type)))
3482 if (complain & tf_error)
3485 error ("parameter %P of %qD has incomplete type %qT",
3488 error ("parameter %P has incomplete type %qT", i, type);
3490 parmval = error_mark_node;
3494 parmval = convert_for_initialization
3495 (NULL_TREE, type, val, flags,
3496 ICR_ARGPASS, fndecl, i, complain);
3497 parmval = convert_for_arg_passing (type, parmval);
3500 if (parmval == error_mark_node)
3503 VEC_replace (tree, *values, i, parmval);
3507 if (fndecl && DECL_BUILT_IN (fndecl)
3508 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3509 /* Don't do ellipsis conversion for __built_in_constant_p
3510 as this will result in spurious errors for non-trivial
3512 val = require_complete_type (val);
3514 val = convert_arg_to_ellipsis (val);
3516 VEC_replace (tree, *values, i, val);
3520 typetail = TREE_CHAIN (typetail);
3523 if (typetail != 0 && typetail != void_list_node)
3525 /* See if there are default arguments that can be used. Because
3526 we hold default arguments in the FUNCTION_TYPE (which is so
3527 wrong), we can see default parameters here from deduced
3528 contexts (and via typeof) for indirect function calls.
3529 Fortunately we know whether we have a function decl to
3530 provide default arguments in a language conformant
3532 if (fndecl && TREE_PURPOSE (typetail)
3533 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3535 for (; typetail != void_list_node; ++i)
3538 = convert_default_arg (TREE_VALUE (typetail),
3539 TREE_PURPOSE (typetail),
3542 if (parmval == error_mark_node)
3545 VEC_safe_push (tree, gc, *values, parmval);
3546 typetail = TREE_CHAIN (typetail);
3547 /* ends with `...'. */
3548 if (typetail == NULL_TREE)
3554 if (complain & tf_error)
3555 warn_args_num (input_location, fndecl, /*too_many_p=*/false);
3563 /* Build a binary-operation expression, after performing default
3564 conversions on the operands. CODE is the kind of expression to
3565 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3566 are the tree codes which correspond to ARG1 and ARG2 when issuing
3567 warnings about possibly misplaced parentheses. They may differ
3568 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3569 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3570 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3571 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3572 ARG2_CODE as ERROR_MARK. */
3575 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3576 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3577 tsubst_flags_t complain)
3586 if (processing_template_decl)
3588 if (type_dependent_expression_p (arg1)
3589 || type_dependent_expression_p (arg2))
3590 return build_min_nt (code, arg1, arg2);
3591 arg1 = build_non_dependent_expr (arg1);
3592 arg2 = build_non_dependent_expr (arg2);
3595 if (code == DOTSTAR_EXPR)
3596 expr = build_m_component_ref (arg1, arg2);
3598 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3599 overloaded_p, complain);
3601 /* Check for cases such as x+y<<z which users are likely to
3602 misinterpret. But don't warn about obj << x + y, since that is a
3603 common idiom for I/O. */
3604 if (warn_parentheses
3605 && (complain & tf_warning)
3606 && !processing_template_decl
3607 && !error_operand_p (arg1)
3608 && !error_operand_p (arg2)
3609 && (code != LSHIFT_EXPR
3610 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3611 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3613 if (processing_template_decl && expr != error_mark_node)
3614 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3619 /* Build and return an ARRAY_REF expression. */
3622 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3624 tree orig_arg1 = arg1;
3625 tree orig_arg2 = arg2;
3628 if (processing_template_decl)
3630 if (type_dependent_expression_p (arg1)
3631 || type_dependent_expression_p (arg2))
3632 return build_min_nt (ARRAY_REF, arg1, arg2,
3633 NULL_TREE, NULL_TREE);
3634 arg1 = build_non_dependent_expr (arg1);
3635 arg2 = build_non_dependent_expr (arg2);
3638 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3639 /*overloaded_p=*/NULL, complain);
3641 if (processing_template_decl && expr != error_mark_node)
3642 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3643 NULL_TREE, NULL_TREE);
3647 /* For the c-common bits. */
3649 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3650 int convert_p ATTRIBUTE_UNUSED)
3652 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3656 /* Build a binary-operation expression without default conversions.
3657 CODE is the kind of expression to build.
3658 LOCATION is the location_t of the operator in the source code.
3659 This function differs from `build' in several ways:
3660 the data type of the result is computed and recorded in it,
3661 warnings are generated if arg data types are invalid,
3662 special handling for addition and subtraction of pointers is known,
3663 and some optimization is done (operations on narrow ints
3664 are done in the narrower type when that gives the same result).
3665 Constant folding is also done before the result is returned.
3667 Note that the operands will never have enumeral types
3668 because either they have just had the default conversions performed
3669 or they have both just been converted to some other type in which
3670 the arithmetic is to be done.
3672 C++: must do special pointer arithmetic when implementing
3673 multiple inheritance, and deal with pointer to member functions. */
3676 cp_build_binary_op (location_t location,
3677 enum tree_code code, tree orig_op0, tree orig_op1,
3678 tsubst_flags_t complain)
3681 enum tree_code code0, code1;
3683 const char *invalid_op_diag;
3685 /* Expression code to give to the expression when it is built.
3686 Normally this is CODE, which is what the caller asked for,
3687 but in some special cases we change it. */
3688 enum tree_code resultcode = code;
3690 /* Data type in which the computation is to be performed.
3691 In the simplest cases this is the common type of the arguments. */
3692 tree result_type = NULL;
3694 /* Nonzero means operands have already been type-converted
3695 in whatever way is necessary.
3696 Zero means they need to be converted to RESULT_TYPE. */
3699 /* Nonzero means create the expression with this type, rather than
3701 tree build_type = 0;
3703 /* Nonzero means after finally constructing the expression
3704 convert it to this type. */
3705 tree final_type = 0;
3709 /* Nonzero if this is an operation like MIN or MAX which can
3710 safely be computed in short if both args are promoted shorts.
3711 Also implies COMMON.
3712 -1 indicates a bitwise operation; this makes a difference
3713 in the exact conditions for when it is safe to do the operation
3714 in a narrower mode. */
3717 /* Nonzero if this is a comparison operation;
3718 if both args are promoted shorts, compare the original shorts.
3719 Also implies COMMON. */
3720 int short_compare = 0;
3722 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3725 /* True if both operands have arithmetic type. */
3726 bool arithmetic_types_p;
3728 /* Apply default conversions. */
3732 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3733 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3734 || code == TRUTH_XOR_EXPR)
3736 if (!really_overloaded_fn (op0))
3737 op0 = decay_conversion (op0);
3738 if (!really_overloaded_fn (op1))
3739 op1 = decay_conversion (op1);
3743 if (!really_overloaded_fn (op0))
3744 op0 = default_conversion (op0);
3745 if (!really_overloaded_fn (op1))
3746 op1 = default_conversion (op1);
3749 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3750 STRIP_TYPE_NOPS (op0);
3751 STRIP_TYPE_NOPS (op1);
3753 /* DTRT if one side is an overloaded function, but complain about it. */
3754 if (type_unknown_p (op0))
3756 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3757 if (t != error_mark_node)
3759 if (complain & tf_error)
3760 permerror (input_location, "assuming cast to type %qT from overloaded function",
3765 if (type_unknown_p (op1))
3767 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3768 if (t != error_mark_node)
3770 if (complain & tf_error)
3771 permerror (input_location, "assuming cast to type %qT from overloaded function",
3777 type0 = TREE_TYPE (op0);
3778 type1 = TREE_TYPE (op1);
3780 /* The expression codes of the data types of the arguments tell us
3781 whether the arguments are integers, floating, pointers, etc. */
3782 code0 = TREE_CODE (type0);
3783 code1 = TREE_CODE (type1);
3785 /* If an error was already reported for one of the arguments,
3786 avoid reporting another error. */
3787 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3788 return error_mark_node;
3790 if ((invalid_op_diag
3791 = targetm.invalid_binary_op (code, type0, type1)))
3793 error (invalid_op_diag);
3794 return error_mark_node;
3797 /* Issue warnings about peculiar, but valid, uses of NULL. */
3798 if ((orig_op0 == null_node || orig_op1 == null_node)
3799 /* It's reasonable to use pointer values as operands of &&
3800 and ||, so NULL is no exception. */
3801 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3802 && ( /* Both are NULL (or 0) and the operation was not a
3803 comparison or a pointer subtraction. */
3804 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3805 && code != EQ_EXPR && code != NE_EXPR && code != MINUS_EXPR)
3806 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3807 || (!null_ptr_cst_p (orig_op0)
3808 && !TYPE_PTR_P (type0) && !TYPE_PTR_TO_MEMBER_P (type0))
3809 || (!null_ptr_cst_p (orig_op1)
3810 && !TYPE_PTR_P (type1) && !TYPE_PTR_TO_MEMBER_P (type1)))
3811 && (complain & tf_warning))
3812 /* Some sort of arithmetic operation involving NULL was
3814 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3819 /* Subtraction of two similar pointers.
3820 We must subtract them as integers, then divide by object size. */
3821 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3822 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3824 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3825 /* In all other cases except pointer - int, the usual arithmetic
3827 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3832 /* The pointer - int case is just like pointer + int; fall
3835 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3836 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3840 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3841 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3842 if (processing_template_decl)
3844 result_type = TREE_TYPE (ptr_operand);
3847 return cp_pointer_int_sum (code,
3858 case TRUNC_DIV_EXPR:
3860 case FLOOR_DIV_EXPR:
3861 case ROUND_DIV_EXPR:
3862 case EXACT_DIV_EXPR:
3863 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3864 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3865 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3866 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3868 enum tree_code tcode0 = code0, tcode1 = code1;
3870 warn_for_div_by_zero (location, op1);
3872 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3873 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3874 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3875 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3877 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3878 resultcode = RDIV_EXPR;
3880 /* When dividing two signed integers, we have to promote to int.
3881 unless we divide by a constant != -1. Note that default
3882 conversion will have been performed on the operands at this
3883 point, so we have to dig out the original type to find out if
3885 shorten = ((TREE_CODE (op0) == NOP_EXPR
3886 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3887 || (TREE_CODE (op1) == INTEGER_CST
3888 && ! integer_all_onesp (op1)));
3897 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3898 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3899 && !VECTOR_FLOAT_TYPE_P (type0)
3900 && !VECTOR_FLOAT_TYPE_P (type1)))
3904 case TRUNC_MOD_EXPR:
3905 case FLOOR_MOD_EXPR:
3906 warn_for_div_by_zero (location, op1);
3908 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3909 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3910 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3912 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3914 /* Although it would be tempting to shorten always here, that loses
3915 on some targets, since the modulo instruction is undefined if the
3916 quotient can't be represented in the computation mode. We shorten
3917 only if unsigned or if dividing by something we know != -1. */
3918 shorten = ((TREE_CODE (op0) == NOP_EXPR
3919 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3920 || (TREE_CODE (op1) == INTEGER_CST
3921 && ! integer_all_onesp (op1)));
3926 case TRUTH_ANDIF_EXPR:
3927 case TRUTH_ORIF_EXPR:
3928 case TRUTH_AND_EXPR:
3930 result_type = boolean_type_node;
3933 /* Shift operations: result has same type as first operand;
3934 always convert second operand to int.
3935 Also set SHORT_SHIFT if shifting rightward. */
3938 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3940 result_type = type0;
3941 if (TREE_CODE (op1) == INTEGER_CST)
3943 if (tree_int_cst_lt (op1, integer_zero_node))
3945 if ((complain & tf_warning)
3946 && c_inhibit_evaluation_warnings == 0)
3947 warning (0, "right shift count is negative");
3951 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3952 && (complain & tf_warning)
3953 && c_inhibit_evaluation_warnings == 0)
3954 warning (0, "right shift count >= width of type");
3957 /* Convert the shift-count to an integer, regardless of
3958 size of value being shifted. */
3959 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3960 op1 = cp_convert (integer_type_node, op1);
3961 /* Avoid converting op1 to result_type later. */
3967 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3969 result_type = type0;
3970 if (TREE_CODE (op1) == INTEGER_CST)
3972 if (tree_int_cst_lt (op1, integer_zero_node))
3974 if ((complain & tf_warning)
3975 && c_inhibit_evaluation_warnings == 0)
3976 warning (0, "left shift count is negative");
3978 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3980 if ((complain & tf_warning)
3981 && c_inhibit_evaluation_warnings == 0)
3982 warning (0, "left shift count >= width of type");
3985 /* Convert the shift-count to an integer, regardless of
3986 size of value being shifted. */
3987 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3988 op1 = cp_convert (integer_type_node, op1);
3989 /* Avoid converting op1 to result_type later. */
3996 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3998 result_type = type0;
3999 if (TREE_CODE (op1) == INTEGER_CST)
4001 if (tree_int_cst_lt (op1, integer_zero_node))
4003 if (complain & tf_warning)
4004 warning (0, (code == LROTATE_EXPR)
4005 ? G_("left rotate count is negative")
4006 : G_("right rotate count is negative"));
4008 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
4010 if (complain & tf_warning)
4011 warning (0, (code == LROTATE_EXPR)
4012 ? G_("left rotate count >= width of type")
4013 : G_("right rotate count >= width of type"));
4016 /* Convert the shift-count to an integer, regardless of
4017 size of value being shifted. */
4018 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
4019 op1 = cp_convert (integer_type_node, op1);
4025 if ((complain & tf_warning)
4026 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
4027 warning (OPT_Wfloat_equal,
4028 "comparing floating point with == or != is unsafe");
4029 if ((complain & tf_warning)
4030 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
4031 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
4032 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
4034 build_type = boolean_type_node;
4035 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
4036 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
4037 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4038 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
4040 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4041 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
4042 result_type = composite_pointer_type (type0, type1, op0, op1,
4043 CPO_COMPARISON, complain);
4044 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
4045 && null_ptr_cst_p (op1))
4047 if (TREE_CODE (op0) == ADDR_EXPR
4048 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
4050 if (complain & tf_warning)
4051 warning (OPT_Waddress, "the address of %qD will never be NULL",
4052 TREE_OPERAND (op0, 0));
4054 result_type = type0;
4056 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
4057 && null_ptr_cst_p (op0))
4059 if (TREE_CODE (op1) == ADDR_EXPR
4060 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
4062 if (complain & tf_warning)
4063 warning (OPT_Waddress, "the address of %qD will never be NULL",
4064 TREE_OPERAND (op1, 0));
4066 result_type = type1;
4068 else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1))
4069 /* One of the operands must be of nullptr_t type. */
4070 result_type = TREE_TYPE (nullptr_node);
4071 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
4073 result_type = type0;
4074 if (complain & tf_error)
4075 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4077 return error_mark_node;
4079 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
4081 result_type = type1;
4082 if (complain & tf_error)
4083 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4085 return error_mark_node;
4087 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
4089 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
4090 == ptrmemfunc_vbit_in_delta)
4092 tree pfn0 = pfn_from_ptrmemfunc (op0);
4093 tree delta0 = delta_from_ptrmemfunc (op0);
4094 tree e1 = cp_build_binary_op (location,
4097 fold_convert (TREE_TYPE (pfn0),
4100 tree e2 = cp_build_binary_op (location,
4105 e2 = cp_build_binary_op (location,
4106 EQ_EXPR, e2, integer_zero_node,
4108 op0 = cp_build_binary_op (location,
4109 TRUTH_ANDIF_EXPR, e1, e2,
4111 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
4115 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
4116 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
4118 result_type = TREE_TYPE (op0);
4120 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
4121 return cp_build_binary_op (location, code, op1, op0, complain);
4122 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
4125 /* E will be the final comparison. */
4127 /* E1 and E2 are for scratch. */
4135 type = composite_pointer_type (type0, type1, op0, op1,
4136 CPO_COMPARISON, complain);
4138 if (!same_type_p (TREE_TYPE (op0), type))
4139 op0 = cp_convert_and_check (type, op0);
4140 if (!same_type_p (TREE_TYPE (op1), type))
4141 op1 = cp_convert_and_check (type, op1);
4143 if (op0 == error_mark_node || op1 == error_mark_node)
4144 return error_mark_node;
4146 if (TREE_SIDE_EFFECTS (op0))
4147 op0 = save_expr (op0);
4148 if (TREE_SIDE_EFFECTS (op1))
4149 op1 = save_expr (op1);
4151 pfn0 = pfn_from_ptrmemfunc (op0);
4152 pfn1 = pfn_from_ptrmemfunc (op1);
4153 delta0 = delta_from_ptrmemfunc (op0);
4154 delta1 = delta_from_ptrmemfunc (op1);
4155 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
4156 == ptrmemfunc_vbit_in_delta)
4161 && ((op0.delta == op1.delta)
4162 || (!op0.pfn && op0.delta & 1 == 0
4163 && op1.delta & 1 == 0))
4165 The reason for the `!op0.pfn' bit is that a NULL
4166 pointer-to-member is any member with a zero PFN and
4167 LSB of the DELTA field is 0. */
4169 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
4173 e1 = cp_build_binary_op (location,
4174 EQ_EXPR, e1, integer_zero_node,
4176 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
4180 e2 = cp_build_binary_op (location,
4181 EQ_EXPR, e2, integer_zero_node,
4183 e1 = cp_build_binary_op (location,
4184 TRUTH_ANDIF_EXPR, e2, e1,
4186 e2 = cp_build_binary_op (location, EQ_EXPR,
4188 fold_convert (TREE_TYPE (pfn0),
4191 e2 = cp_build_binary_op (location,
4192 TRUTH_ANDIF_EXPR, e2, e1, complain);
4193 e1 = cp_build_binary_op (location,
4194 EQ_EXPR, delta0, delta1, complain);
4195 e1 = cp_build_binary_op (location,
4196 TRUTH_ORIF_EXPR, e1, e2, complain);
4203 && (!op0.pfn || op0.delta == op1.delta))
4205 The reason for the `!op0.pfn' bit is that a NULL
4206 pointer-to-member is any member with a zero PFN; the
4207 DELTA field is unspecified. */
4209 e1 = cp_build_binary_op (location,
4210 EQ_EXPR, delta0, delta1, complain);
4211 e2 = cp_build_binary_op (location,
4214 fold_convert (TREE_TYPE (pfn0),
4217 e1 = cp_build_binary_op (location,
4218 TRUTH_ORIF_EXPR, e1, e2, complain);
4220 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
4221 e = cp_build_binary_op (location,
4222 TRUTH_ANDIF_EXPR, e2, e1, complain);
4223 if (code == EQ_EXPR)
4225 return cp_build_binary_op (location,
4226 EQ_EXPR, e, integer_zero_node, complain);
4230 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
4231 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
4233 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
4234 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
4242 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
4243 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
4245 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4246 result_type = composite_pointer_type (type0, type1, op0, op1,
4247 CPO_COMPARISON, complain);
4254 if (TREE_CODE (orig_op0) == STRING_CST
4255 || TREE_CODE (orig_op1) == STRING_CST)
4257 if (complain & tf_warning)
4258 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
4261 build_type = boolean_type_node;
4262 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
4263 || code0 == ENUMERAL_TYPE)
4264 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4265 || code1 == ENUMERAL_TYPE))
4267 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4268 result_type = composite_pointer_type (type0, type1, op0, op1,
4269 CPO_COMPARISON, complain);
4270 else if (code0 == POINTER_TYPE && null_ptr_cst_p (op1))
4271 result_type = type0;
4272 else if (code1 == POINTER_TYPE && null_ptr_cst_p (op0))
4273 result_type = type1;
4274 else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1))
4275 /* One of the operands must be of nullptr_t type. */
4276 result_type = TREE_TYPE (nullptr_node);
4277 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
4279 result_type = type0;
4280 if (complain & tf_error)
4281 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4283 return error_mark_node;
4285 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
4287 result_type = type1;
4288 if (complain & tf_error)
4289 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4291 return error_mark_node;
4295 case UNORDERED_EXPR:
4302 build_type = integer_type_node;
4303 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
4305 if (complain & tf_error)
4306 error ("unordered comparison on non-floating point argument");
4307 return error_mark_node;
4316 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
4317 || code0 == ENUMERAL_TYPE)
4318 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4319 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
4320 arithmetic_types_p = 1;
4323 arithmetic_types_p = 0;
4324 /* Vector arithmetic is only allowed when both sides are vectors. */
4325 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
4327 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
4328 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
4331 binary_op_error (location, code, type0, type1);
4332 return error_mark_node;
4334 arithmetic_types_p = 1;
4337 /* Determine the RESULT_TYPE, if it is not already known. */
4339 && arithmetic_types_p
4340 && (shorten || common || short_compare))
4341 result_type = cp_common_type (type0, type1);
4345 if (complain & tf_error)
4346 error ("invalid operands of types %qT and %qT to binary %qO",
4347 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
4348 return error_mark_node;
4351 /* If we're in a template, the only thing we need to know is the
4353 if (processing_template_decl)
4355 /* Since the middle-end checks the type when doing a build2, we
4356 need to build the tree in pieces. This built tree will never
4357 get out of the front-end as we replace it when instantiating
4359 tree tmp = build2 (resultcode,
4360 build_type ? build_type : result_type,
4362 TREE_OPERAND (tmp, 0) = op0;
4366 if (arithmetic_types_p)
4368 bool first_complex = (code0 == COMPLEX_TYPE);
4369 bool second_complex = (code1 == COMPLEX_TYPE);
4370 int none_complex = (!first_complex && !second_complex);
4372 /* Adapted from patch for c/24581. */
4373 if (first_complex != second_complex
4374 && (code == PLUS_EXPR
4375 || code == MINUS_EXPR
4376 || code == MULT_EXPR
4377 || (code == TRUNC_DIV_EXPR && first_complex))
4378 && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE
4379 && flag_signed_zeros)
4381 /* An operation on mixed real/complex operands must be
4382 handled specially, but the language-independent code can
4383 more easily optimize the plain complex arithmetic if
4384 -fno-signed-zeros. */
4385 tree real_type = TREE_TYPE (result_type);
4389 if (TREE_TYPE (op0) != result_type)
4390 op0 = cp_convert_and_check (result_type, op0);
4391 if (TREE_TYPE (op1) != real_type)
4392 op1 = cp_convert_and_check (real_type, op1);
4396 if (TREE_TYPE (op0) != real_type)
4397 op0 = cp_convert_and_check (real_type, op0);
4398 if (TREE_TYPE (op1) != result_type)
4399 op1 = cp_convert_and_check (result_type, op1);
4401 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
4402 return error_mark_node;
4405 op0 = save_expr (op0);
4406 real = cp_build_unary_op (REALPART_EXPR, op0, 1, complain);
4407 imag = cp_build_unary_op (IMAGPART_EXPR, op0, 1, complain);
4411 case TRUNC_DIV_EXPR:
4412 imag = build2 (resultcode, real_type, imag, op1);
4416 real = build2 (resultcode, real_type, real, op1);
4424 op1 = save_expr (op1);
4425 real = cp_build_unary_op (REALPART_EXPR, op1, 1, complain);
4426 imag = cp_build_unary_op (IMAGPART_EXPR, op1, 1, complain);
4430 imag = build2 (resultcode, real_type, op0, imag);
4433 real = build2 (resultcode, real_type, op0, real);
4436 real = build2 (resultcode, real_type, op0, real);
4437 imag = build1 (NEGATE_EXPR, real_type, imag);
4443 return build2 (COMPLEX_EXPR, result_type, real, imag);
4446 /* For certain operations (which identify themselves by shorten != 0)
4447 if both args were extended from the same smaller type,
4448 do the arithmetic in that type and then extend.
4450 shorten !=0 and !=1 indicates a bitwise operation.
4451 For them, this optimization is safe only if
4452 both args are zero-extended or both are sign-extended.
4453 Otherwise, we might change the result.
4454 E.g., (short)-1 | (unsigned short)-1 is (int)-1
4455 but calculated in (unsigned short) it would be (unsigned short)-1. */
4457 if (shorten && none_complex)
4459 final_type = result_type;
4460 result_type = shorten_binary_op (result_type, op0, op1,
4464 /* Comparison operations are shortened too but differently.
4465 They identify themselves by setting short_compare = 1. */
4469 /* Don't write &op0, etc., because that would prevent op0
4470 from being kept in a register.
4471 Instead, make copies of the our local variables and
4472 pass the copies by reference, then copy them back afterward. */
4473 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4474 enum tree_code xresultcode = resultcode;
4476 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4478 return cp_convert (boolean_type_node, val);
4479 op0 = xop0, op1 = xop1;
4481 resultcode = xresultcode;
4484 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4485 && warn_sign_compare
4486 && !TREE_NO_WARNING (orig_op0)
4487 && !TREE_NO_WARNING (orig_op1)
4488 /* Do not warn until the template is instantiated; we cannot
4489 bound the ranges of the arguments until that point. */
4490 && !processing_template_decl
4491 && (complain & tf_warning)
4492 && c_inhibit_evaluation_warnings == 0)
4494 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4495 result_type, resultcode);
4499 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4500 Then the expression will be built.
4501 It will be given type FINAL_TYPE if that is nonzero;
4502 otherwise, it will be given type RESULT_TYPE. */
4505 if (TREE_TYPE (op0) != result_type)
4506 op0 = cp_convert_and_check (result_type, op0);
4507 if (TREE_TYPE (op1) != result_type)
4508 op1 = cp_convert_and_check (result_type, op1);
4510 if (op0 == error_mark_node || op1 == error_mark_node)
4511 return error_mark_node;
4514 if (build_type == NULL_TREE)
4515 build_type = result_type;
4517 result = build2 (resultcode, build_type, op0, op1);
4518 result = fold_if_not_in_template (result);
4519 if (final_type != 0)
4520 result = cp_convert (final_type, result);
4522 if (TREE_OVERFLOW_P (result)
4523 && !TREE_OVERFLOW_P (op0)
4524 && !TREE_OVERFLOW_P (op1))
4525 overflow_warning (location, result);
4530 /* Return a tree for the sum or difference (RESULTCODE says which)
4531 of pointer PTROP and integer INTOP. */
4534 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4536 tree res_type = TREE_TYPE (ptrop);
4538 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4539 in certain circumstance (when it's valid to do so). So we need
4540 to make sure it's complete. We don't need to check here, if we
4541 can actually complete it at all, as those checks will be done in
4542 pointer_int_sum() anyway. */
4543 complete_type (TREE_TYPE (res_type));
4545 return pointer_int_sum (input_location, resultcode, ptrop,
4546 fold_if_not_in_template (intop));
4549 /* Return a tree for the difference of pointers OP0 and OP1.
4550 The resulting tree has type int. */
4553 pointer_diff (tree op0, tree op1, tree ptrtype)
4556 tree restype = ptrdiff_type_node;
4557 tree target_type = TREE_TYPE (ptrtype);
4559 if (!complete_type_or_else (target_type, NULL_TREE))
4560 return error_mark_node;
4562 if (TREE_CODE (target_type) == VOID_TYPE)
4563 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4564 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4565 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4566 if (TREE_CODE (target_type) == METHOD_TYPE)
4567 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4569 /* First do the subtraction as integers;
4570 then drop through to build the divide operator. */
4572 op0 = cp_build_binary_op (input_location,
4574 cp_convert (restype, op0),
4575 cp_convert (restype, op1),
4576 tf_warning_or_error);
4578 /* This generates an error if op1 is a pointer to an incomplete type. */
4579 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4580 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4582 op1 = (TYPE_PTROB_P (ptrtype)
4583 ? size_in_bytes (target_type)
4584 : integer_one_node);
4586 /* Do the division. */
4588 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4589 return fold_if_not_in_template (result);
4592 /* Construct and perhaps optimize a tree representation
4593 for a unary operation. CODE, a tree_code, specifies the operation
4594 and XARG is the operand. */
4597 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4599 tree orig_expr = xarg;
4603 if (processing_template_decl)
4605 if (type_dependent_expression_p (xarg))
4606 return build_min_nt (code, xarg, NULL_TREE);
4608 xarg = build_non_dependent_expr (xarg);
4613 /* [expr.unary.op] says:
4615 The address of an object of incomplete type can be taken.
4617 (And is just the ordinary address operator, not an overloaded
4618 "operator &".) However, if the type is a template
4619 specialization, we must complete the type at this point so that
4620 an overloaded "operator &" will be available if required. */
4621 if (code == ADDR_EXPR
4622 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4623 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4624 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4625 || (TREE_CODE (xarg) == OFFSET_REF)))
4626 /* Don't look for a function. */;
4628 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4629 /*overloaded_p=*/NULL, complain);
4630 if (!exp && code == ADDR_EXPR)
4632 if (is_overloaded_fn (xarg))
4634 tree fn = get_first_fn (xarg);
4635 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4637 error (DECL_CONSTRUCTOR_P (fn)
4638 ? G_("taking address of constructor %qE")
4639 : G_("taking address of destructor %qE"),
4641 return error_mark_node;
4645 /* A pointer to member-function can be formed only by saying
4647 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4648 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4650 if (TREE_CODE (xarg) != OFFSET_REF
4651 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4653 error ("invalid use of %qE to form a pointer-to-member-function",
4655 if (TREE_CODE (xarg) != OFFSET_REF)
4656 inform (input_location, " a qualified-id is required");
4657 return error_mark_node;
4661 error ("parentheses around %qE cannot be used to form a"
4662 " pointer-to-member-function",
4664 PTRMEM_OK_P (xarg) = 1;
4668 if (TREE_CODE (xarg) == OFFSET_REF)
4670 ptrmem = PTRMEM_OK_P (xarg);
4672 if (!ptrmem && !flag_ms_extensions
4673 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4675 /* A single non-static member, make sure we don't allow a
4676 pointer-to-member. */
4677 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4678 TREE_OPERAND (xarg, 0),
4679 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4680 PTRMEM_OK_P (xarg) = ptrmem;
4683 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4684 warning (0, "taking address of temporary");
4685 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4688 if (processing_template_decl && exp != error_mark_node)
4689 exp = build_min_non_dep (code, exp, orig_expr,
4690 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4691 if (TREE_CODE (exp) == ADDR_EXPR)
4692 PTRMEM_OK_P (exp) = ptrmem;
4696 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4697 constants, where a null value is represented by an INTEGER_CST of
4701 cp_truthvalue_conversion (tree expr)
4703 tree type = TREE_TYPE (expr);
4704 if (TYPE_PTRMEM_P (type))
4705 return build_binary_op (EXPR_LOCATION (expr),
4706 NE_EXPR, expr, integer_zero_node, 1);
4708 return c_common_truthvalue_conversion (input_location, expr);
4711 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4714 condition_conversion (tree expr)
4717 if (processing_template_decl)
4719 t = perform_implicit_conversion_flags (boolean_type_node, expr,
4720 tf_warning_or_error, LOOKUP_NORMAL);
4721 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4725 /* Returns the address of T. This function will fold away
4726 ADDR_EXPR of INDIRECT_REF. */
4729 build_address (tree t)
4731 if (error_operand_p (t) || !cxx_mark_addressable (t))
4732 return error_mark_node;
4733 t = build_fold_addr_expr (t);
4734 if (TREE_CODE (t) != ADDR_EXPR)
4739 /* Returns the address of T with type TYPE. */
4742 build_typed_address (tree t, tree type)
4744 if (error_operand_p (t) || !cxx_mark_addressable (t))
4745 return error_mark_node;
4746 t = build_fold_addr_expr_with_type (t, type);
4747 if (TREE_CODE (t) != ADDR_EXPR)
4752 /* Return a NOP_EXPR converting EXPR to TYPE. */
4755 build_nop (tree type, tree expr)
4757 if (type == error_mark_node || error_operand_p (expr))
4759 return build1 (NOP_EXPR, type, expr);
4762 /* C++: Must handle pointers to members.
4764 Perhaps type instantiation should be extended to handle conversion
4765 from aggregates to types we don't yet know we want? (Or are those
4766 cases typically errors which should be reported?)
4768 NOCONVERT nonzero suppresses the default promotions
4769 (such as from short to int). */
4772 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4773 tsubst_flags_t complain)
4775 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4778 const char *errstring = NULL;
4780 const char *invalid_op_diag;
4782 if (error_operand_p (arg))
4783 return error_mark_node;
4785 if ((invalid_op_diag
4786 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4791 error (invalid_op_diag);
4792 return error_mark_node;
4797 case UNARY_PLUS_EXPR:
4800 int flags = WANT_ARITH | WANT_ENUM;
4801 /* Unary plus (but not unary minus) is allowed on pointers. */
4802 if (code == UNARY_PLUS_EXPR)
4803 flags |= WANT_POINTER;
4804 arg = build_expr_type_conversion (flags, arg, true);
4806 errstring = (code == NEGATE_EXPR
4807 ? _("wrong type argument to unary minus")
4808 : _("wrong type argument to unary plus"));
4811 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4812 arg = perform_integral_promotions (arg);
4814 /* Make sure the result is not an lvalue: a unary plus or minus
4815 expression is always a rvalue. */
4822 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4826 arg = default_conversion (arg);
4828 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4829 | WANT_VECTOR_OR_COMPLEX,
4831 errstring = _("wrong type argument to bit-complement");
4832 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4833 arg = perform_integral_promotions (arg);
4837 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4838 errstring = _("wrong type argument to abs");
4839 else if (!noconvert)
4840 arg = default_conversion (arg);
4844 /* Conjugating a real value is a no-op, but allow it anyway. */
4845 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4846 errstring = _("wrong type argument to conjugation");
4847 else if (!noconvert)
4848 arg = default_conversion (arg);
4851 case TRUTH_NOT_EXPR:
4852 arg = perform_implicit_conversion (boolean_type_node, arg,
4854 val = invert_truthvalue_loc (input_location, arg);
4855 if (arg != error_mark_node)
4857 errstring = _("in argument to unary !");
4864 if (TREE_CODE (arg) == COMPLEX_CST)
4865 return TREE_REALPART (arg);
4866 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4868 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4869 return fold_if_not_in_template (arg);
4875 if (TREE_CODE (arg) == COMPLEX_CST)
4876 return TREE_IMAGPART (arg);
4877 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4879 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4880 return fold_if_not_in_template (arg);
4883 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4885 case PREINCREMENT_EXPR:
4886 case POSTINCREMENT_EXPR:
4887 case PREDECREMENT_EXPR:
4888 case POSTDECREMENT_EXPR:
4889 /* Handle complex lvalues (when permitted)
4890 by reduction to simpler cases. */
4892 val = unary_complex_lvalue (code, arg);
4896 arg = mark_lvalue_use (arg);
4898 /* Increment or decrement the real part of the value,
4899 and don't change the imaginary part. */
4900 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4904 arg = stabilize_reference (arg);
4905 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4906 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4907 real = cp_build_unary_op (code, real, 1, complain);
4908 if (real == error_mark_node || imag == error_mark_node)
4909 return error_mark_node;
4910 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4914 /* Report invalid types. */
4916 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4919 if (code == PREINCREMENT_EXPR)
4920 errstring = _("no pre-increment operator for type");
4921 else if (code == POSTINCREMENT_EXPR)
4922 errstring = _("no post-increment operator for type");
4923 else if (code == PREDECREMENT_EXPR)
4924 errstring = _("no pre-decrement operator for type");
4926 errstring = _("no post-decrement operator for type");
4929 else if (arg == error_mark_node)
4930 return error_mark_node;
4932 /* Report something read-only. */
4934 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4935 || TREE_READONLY (arg))
4937 if (complain & tf_error)
4938 readonly_error (arg, ((code == PREINCREMENT_EXPR
4939 || code == POSTINCREMENT_EXPR)
4940 ? REK_INCREMENT : REK_DECREMENT));
4942 return error_mark_node;
4947 tree declared_type = unlowered_expr_type (arg);
4949 argtype = TREE_TYPE (arg);
4951 /* ARM $5.2.5 last annotation says this should be forbidden. */
4952 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4954 if (complain & tf_error)
4955 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4956 ? G_("ISO C++ forbids incrementing an enum")
4957 : G_("ISO C++ forbids decrementing an enum"));
4959 return error_mark_node;
4962 /* Compute the increment. */
4964 if (TREE_CODE (argtype) == POINTER_TYPE)
4966 tree type = complete_type (TREE_TYPE (argtype));
4968 if (!COMPLETE_OR_VOID_TYPE_P (type))
4970 if (complain & tf_error)
4971 error (((code == PREINCREMENT_EXPR
4972 || code == POSTINCREMENT_EXPR))
4973 ? G_("cannot increment a pointer to incomplete type %qT")
4974 : G_("cannot decrement a pointer to incomplete type %qT"),
4975 TREE_TYPE (argtype));
4977 return error_mark_node;
4979 else if ((pedantic || warn_pointer_arith)
4980 && !TYPE_PTROB_P (argtype))
4982 if (complain & tf_error)
4983 permerror (input_location, (code == PREINCREMENT_EXPR
4984 || code == POSTINCREMENT_EXPR)
4985 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4986 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4989 return error_mark_node;
4992 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4995 inc = integer_one_node;
4997 inc = cp_convert (argtype, inc);
4999 /* Complain about anything else that is not a true lvalue. */
5000 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
5001 || code == POSTINCREMENT_EXPR)
5002 ? lv_increment : lv_decrement),
5004 return error_mark_node;
5006 /* Forbid using -- on `bool'. */
5007 if (TREE_CODE (declared_type) == BOOLEAN_TYPE)
5009 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
5011 if (complain & tf_error)
5012 error ("invalid use of Boolean expression as operand "
5013 "to %<operator--%>");
5014 return error_mark_node;
5016 val = boolean_increment (code, arg);
5019 val = build2 (code, TREE_TYPE (arg), arg, inc);
5021 TREE_SIDE_EFFECTS (val) = 1;
5026 /* Note that this operation never does default_conversion
5027 regardless of NOCONVERT. */
5029 argtype = lvalue_type (arg);
5031 arg = mark_lvalue_use (arg);
5033 if (TREE_CODE (arg) == OFFSET_REF)
5036 if (TREE_CODE (argtype) == REFERENCE_TYPE)
5038 tree type = build_pointer_type (TREE_TYPE (argtype));
5039 arg = build1 (CONVERT_EXPR, type, arg);
5042 else if (pedantic && DECL_MAIN_P (arg))
5045 /* Apparently a lot of autoconf scripts for C++ packages do this,
5046 so only complain if -pedantic. */
5047 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
5048 pedwarn (input_location, OPT_pedantic,
5049 "ISO C++ forbids taking address of function %<::main%>");
5050 else if (flag_pedantic_errors)
5051 return error_mark_node;
5054 /* Let &* cancel out to simplify resulting code. */
5055 if (TREE_CODE (arg) == INDIRECT_REF)
5057 /* We don't need to have `current_class_ptr' wrapped in a
5058 NON_LVALUE_EXPR node. */
5059 if (arg == current_class_ref)
5060 return current_class_ptr;
5062 arg = TREE_OPERAND (arg, 0);
5063 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
5065 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
5066 arg = build1 (CONVERT_EXPR, type, arg);
5069 /* Don't let this be an lvalue. */
5074 /* ??? Cope with user tricks that amount to offsetof. */
5075 if (TREE_CODE (argtype) != FUNCTION_TYPE
5076 && TREE_CODE (argtype) != METHOD_TYPE
5077 && argtype != unknown_type_node
5078 && (val = get_base_address (arg))
5079 && TREE_CODE (val) == INDIRECT_REF
5080 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
5082 tree type = build_pointer_type (argtype);
5083 tree op0 = fold_convert (type, TREE_OPERAND (val, 0));
5084 tree op1 = fold_convert (sizetype, fold_offsetof (arg, val));
5085 return fold_build2 (POINTER_PLUS_EXPR, type, op0, op1);
5088 /* Uninstantiated types are all functions. Taking the
5089 address of a function is a no-op, so just return the
5092 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
5093 || !IDENTIFIER_OPNAME_P (arg));
5095 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
5096 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
5098 /* They're trying to take the address of a unique non-static
5099 member function. This is ill-formed (except in MS-land),
5100 but let's try to DTRT.
5101 Note: We only handle unique functions here because we don't
5102 want to complain if there's a static overload; non-unique
5103 cases will be handled by instantiate_type. But we need to
5104 handle this case here to allow casts on the resulting PMF.
5105 We could defer this in non-MS mode, but it's easier to give
5106 a useful error here. */
5108 /* Inside constant member functions, the `this' pointer
5109 contains an extra const qualifier. TYPE_MAIN_VARIANT
5110 is used here to remove this const from the diagnostics
5111 and the created OFFSET_REF. */
5112 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
5113 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
5116 if (! flag_ms_extensions)
5118 tree name = DECL_NAME (fn);
5119 if (!(complain & tf_error))
5120 return error_mark_node;
5121 else if (current_class_type
5122 && TREE_OPERAND (arg, 0) == current_class_ref)
5123 /* An expression like &memfn. */
5124 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
5125 " or parenthesized non-static member function to form"
5126 " a pointer to member function. Say %<&%T::%D%>",
5129 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
5130 " function to form a pointer to member function."
5134 arg = build_offset_ref (base, fn, /*address_p=*/true);
5138 if (type_unknown_p (arg))
5139 return build1 (ADDR_EXPR, unknown_type_node, arg);
5141 /* Handle complex lvalues (when permitted)
5142 by reduction to simpler cases. */
5143 val = unary_complex_lvalue (code, arg);
5147 switch (TREE_CODE (arg))
5151 case FIX_TRUNC_EXPR:
5152 /* Even if we're not being pedantic, we cannot allow this
5153 extension when we're instantiating in a SFINAE
5155 if (! lvalue_p (arg) && complain == tf_none)
5157 if (complain & tf_error)
5158 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
5160 return error_mark_node;
5165 arg = BASELINK_FUNCTIONS (arg);
5169 arg = OVL_CURRENT (arg);
5173 /* Turn a reference to a non-static data member into a
5174 pointer-to-member. */
5179 if (!PTRMEM_OK_P (arg))
5180 return cp_build_unary_op (code, arg, 0, complain);
5182 t = TREE_OPERAND (arg, 1);
5183 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
5185 if (complain & tf_error)
5186 error ("cannot create pointer to reference member %qD", t);
5187 return error_mark_node;
5190 type = build_ptrmem_type (context_for_name_lookup (t),
5192 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
5200 /* Anything not already handled and not a true memory reference
5202 if (TREE_CODE (argtype) != FUNCTION_TYPE
5203 && TREE_CODE (argtype) != METHOD_TYPE
5204 && TREE_CODE (arg) != OFFSET_REF
5205 && !lvalue_or_else (arg, lv_addressof, complain))
5206 return error_mark_node;
5208 if (argtype != error_mark_node)
5209 argtype = build_pointer_type (argtype);
5211 /* In a template, we are processing a non-dependent expression
5212 so we can just form an ADDR_EXPR with the correct type. */
5213 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
5215 val = build_address (arg);
5216 if (TREE_CODE (arg) == OFFSET_REF)
5217 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
5219 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
5221 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
5223 /* We can only get here with a single static member
5225 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5226 && DECL_STATIC_FUNCTION_P (fn));
5228 val = build_address (fn);
5229 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
5230 /* Do not lose object's side effects. */
5231 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
5232 TREE_OPERAND (arg, 0), val);
5234 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
5236 if (complain & tf_error)
5237 error ("attempt to take address of bit-field structure member %qD",
5238 TREE_OPERAND (arg, 1));
5239 return error_mark_node;
5243 tree object = TREE_OPERAND (arg, 0);
5244 tree field = TREE_OPERAND (arg, 1);
5245 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5246 (TREE_TYPE (object), decl_type_context (field)));
5247 val = build_address (arg);
5250 if (TREE_CODE (argtype) == POINTER_TYPE
5251 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
5253 build_ptrmemfunc_type (argtype);
5254 val = build_ptrmemfunc (argtype, val, 0,
5255 /*c_cast_p=*/false);
5267 argtype = TREE_TYPE (arg);
5268 return fold_if_not_in_template (build1 (code, argtype, arg));
5271 if (complain & tf_error)
5272 error ("%s", errstring);
5273 return error_mark_node;
5276 /* Hook for the c-common bits that build a unary op. */
5278 build_unary_op (location_t location ATTRIBUTE_UNUSED,
5279 enum tree_code code, tree xarg, int noconvert)
5281 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
5284 /* Apply unary lvalue-demanding operator CODE to the expression ARG
5285 for certain kinds of expressions which are not really lvalues
5286 but which we can accept as lvalues.
5288 If ARG is not a kind of expression we can handle, return
5292 unary_complex_lvalue (enum tree_code code, tree arg)
5294 /* Inside a template, making these kinds of adjustments is
5295 pointless; we are only concerned with the type of the
5297 if (processing_template_decl)
5300 /* Handle (a, b) used as an "lvalue". */
5301 if (TREE_CODE (arg) == COMPOUND_EXPR)
5303 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
5304 tf_warning_or_error);
5305 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5306 TREE_OPERAND (arg, 0), real_result);
5309 /* Handle (a ? b : c) used as an "lvalue". */
5310 if (TREE_CODE (arg) == COND_EXPR
5311 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
5312 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
5314 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
5315 if (TREE_CODE (arg) == MODIFY_EXPR
5316 || TREE_CODE (arg) == PREINCREMENT_EXPR
5317 || TREE_CODE (arg) == PREDECREMENT_EXPR)
5319 tree lvalue = TREE_OPERAND (arg, 0);
5320 if (TREE_SIDE_EFFECTS (lvalue))
5322 lvalue = stabilize_reference (lvalue);
5323 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
5324 lvalue, TREE_OPERAND (arg, 1));
5326 return unary_complex_lvalue
5327 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
5330 if (code != ADDR_EXPR)
5333 /* Handle (a = b) used as an "lvalue" for `&'. */
5334 if (TREE_CODE (arg) == MODIFY_EXPR
5335 || TREE_CODE (arg) == INIT_EXPR)
5337 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
5338 tf_warning_or_error);
5339 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5341 TREE_NO_WARNING (arg) = 1;
5345 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
5346 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
5347 || TREE_CODE (arg) == OFFSET_REF)
5350 /* We permit compiler to make function calls returning
5351 objects of aggregate type look like lvalues. */
5355 if (TREE_CODE (targ) == SAVE_EXPR)
5356 targ = TREE_OPERAND (targ, 0);
5358 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
5360 if (TREE_CODE (arg) == SAVE_EXPR)
5363 targ = build_cplus_new (TREE_TYPE (arg), arg);
5364 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
5367 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
5368 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
5369 TREE_OPERAND (targ, 0), current_function_decl, NULL);
5372 /* Don't let anything else be handled specially. */
5376 /* Mark EXP saying that we need to be able to take the
5377 address of it; it should not be allocated in a register.
5378 Value is true if successful.
5380 C++: we do not allow `current_class_ptr' to be addressable. */
5383 cxx_mark_addressable (tree exp)
5388 switch (TREE_CODE (x))
5395 x = TREE_OPERAND (x, 0);
5399 if (x == current_class_ptr)
5401 error ("cannot take the address of %<this%>, which is an rvalue expression");
5402 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
5408 /* Caller should not be trying to mark initialized
5409 constant fields addressable. */
5410 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
5411 || DECL_IN_AGGR_P (x) == 0
5413 || DECL_EXTERNAL (x));
5418 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
5419 && !DECL_ARTIFICIAL (x))
5421 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
5424 ("address of explicit register variable %qD requested", x);
5427 else if (extra_warnings)
5429 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
5431 TREE_ADDRESSABLE (x) = 1;
5435 TREE_ADDRESSABLE (x) = 1;
5439 TREE_ADDRESSABLE (x) = 1;
5443 TREE_ADDRESSABLE (x) = 1;
5444 cxx_mark_addressable (TREE_OPERAND (x, 0));
5452 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
5455 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
5456 tsubst_flags_t complain)
5458 tree orig_ifexp = ifexp;
5459 tree orig_op1 = op1;
5460 tree orig_op2 = op2;
5463 if (processing_template_decl)
5465 /* The standard says that the expression is type-dependent if
5466 IFEXP is type-dependent, even though the eventual type of the
5467 expression doesn't dependent on IFEXP. */
5468 if (type_dependent_expression_p (ifexp)
5469 /* As a GNU extension, the middle operand may be omitted. */
5470 || (op1 && type_dependent_expression_p (op1))
5471 || type_dependent_expression_p (op2))
5472 return build_min_nt (COND_EXPR, ifexp, op1, op2);
5473 ifexp = build_non_dependent_expr (ifexp);
5475 op1 = build_non_dependent_expr (op1);
5476 op2 = build_non_dependent_expr (op2);
5479 expr = build_conditional_expr (ifexp, op1, op2, complain);
5480 if (processing_template_decl && expr != error_mark_node)
5481 return build_min_non_dep (COND_EXPR, expr,
5482 orig_ifexp, orig_op1, orig_op2);
5486 /* Given a list of expressions, return a compound expression
5487 that performs them all and returns the value of the last of them. */
5490 build_x_compound_expr_from_list (tree list, expr_list_kind exp)
5492 tree expr = TREE_VALUE (list);
5494 if (TREE_CHAIN (list))
5499 permerror (input_location, "expression list treated as compound "
5500 "expression in initializer");
5503 permerror (input_location, "expression list treated as compound "
5504 "expression in mem-initializer");
5507 permerror (input_location, "expression list treated as compound "
5508 "expression in functional cast");
5514 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5515 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5516 tf_warning_or_error);
5522 /* Like build_x_compound_expr_from_list, but using a VEC. */
5525 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5527 if (VEC_empty (tree, vec))
5529 else if (VEC_length (tree, vec) == 1)
5530 return VEC_index (tree, vec, 0);
5538 permerror (input_location,
5539 "%s expression list treated as compound expression",
5542 expr = VEC_index (tree, vec, 0);
5543 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5544 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5550 /* Handle overloading of the ',' operator when needed. */
5553 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5556 tree orig_op1 = op1;
5557 tree orig_op2 = op2;
5559 if (processing_template_decl)
5561 if (type_dependent_expression_p (op1)
5562 || type_dependent_expression_p (op2))
5563 return build_min_nt (COMPOUND_EXPR, op1, op2);
5564 op1 = build_non_dependent_expr (op1);
5565 op2 = build_non_dependent_expr (op2);
5568 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5569 /*overloaded_p=*/NULL, complain);
5571 result = cp_build_compound_expr (op1, op2, complain);
5573 if (processing_template_decl && result != error_mark_node)
5574 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5579 /* Like cp_build_compound_expr, but for the c-common bits. */
5582 build_compound_expr (location_t loc ATTRIBUTE_UNUSED, tree lhs, tree rhs)
5584 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5587 /* Build a compound expression. */
5590 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5592 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5594 if (lhs == error_mark_node || rhs == error_mark_node)
5595 return error_mark_node;
5597 if (TREE_CODE (rhs) == TARGET_EXPR)
5599 /* If the rhs is a TARGET_EXPR, then build the compound
5600 expression inside the target_expr's initializer. This
5601 helps the compiler to eliminate unnecessary temporaries. */
5602 tree init = TREE_OPERAND (rhs, 1);
5604 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5605 TREE_OPERAND (rhs, 1) = init;
5610 if (type_unknown_p (rhs))
5612 error ("no context to resolve type of %qE", rhs);
5613 return error_mark_node;
5616 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5619 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5620 casts away constness. CAST gives the type of cast.
5622 ??? This function warns for casting away any qualifier not just
5623 const. We would like to specify exactly what qualifiers are casted
5628 check_for_casting_away_constness (tree src_type, tree dest_type,
5629 enum tree_code cast)
5631 /* C-style casts are allowed to cast away constness. With
5632 WARN_CAST_QUAL, we still want to issue a warning. */
5633 if (cast == CAST_EXPR && !warn_cast_qual)
5636 if (!casts_away_constness (src_type, dest_type))
5642 warning (OPT_Wcast_qual,
5643 "cast from type %qT to type %qT casts away qualifiers",
5644 src_type, dest_type);
5647 case STATIC_CAST_EXPR:
5648 error ("static_cast from type %qT to type %qT casts away qualifiers",
5649 src_type, dest_type);
5652 case REINTERPRET_CAST_EXPR:
5653 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5654 src_type, dest_type);
5661 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5662 (another pointer-to-member type in the same hierarchy) and return
5663 the converted expression. If ALLOW_INVERSE_P is permitted, a
5664 pointer-to-derived may be converted to pointer-to-base; otherwise,
5665 only the other direction is permitted. If C_CAST_P is true, this
5666 conversion is taking place as part of a C-style cast. */
5669 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5672 if (TYPE_PTRMEM_P (type))
5676 if (TREE_CODE (expr) == PTRMEM_CST)
5677 expr = cplus_expand_constant (expr);
5678 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5679 TYPE_PTRMEM_CLASS_TYPE (type),
5682 if (!integer_zerop (delta))
5684 tree cond, op1, op2;
5686 cond = cp_build_binary_op (input_location,
5689 build_int_cst (TREE_TYPE (expr), -1),
5690 tf_warning_or_error);
5691 op1 = build_nop (ptrdiff_type_node, expr);
5692 op2 = cp_build_binary_op (input_location,
5693 PLUS_EXPR, op1, delta,
5694 tf_warning_or_error);
5696 expr = fold_build3_loc (input_location,
5697 COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5701 return build_nop (type, expr);
5704 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5705 allow_inverse_p, c_cast_p);
5708 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5709 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5710 Otherwise, return EXPR unchanged. */
5713 ignore_overflows (tree expr, tree orig)
5715 if (TREE_CODE (expr) == INTEGER_CST
5716 && CONSTANT_CLASS_P (orig)
5717 && TREE_CODE (orig) != STRING_CST
5718 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5720 if (!TREE_OVERFLOW (orig))
5721 /* Ensure constant sharing. */
5722 expr = build_int_cst_wide (TREE_TYPE (expr),
5723 TREE_INT_CST_LOW (expr),
5724 TREE_INT_CST_HIGH (expr));
5727 /* Avoid clobbering a shared constant. */
5728 expr = copy_node (expr);
5729 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5735 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5736 this static_cast is being attempted as one of the possible casts
5737 allowed by a C-style cast. (In that case, accessibility of base
5738 classes is not considered, and it is OK to cast away
5739 constness.) Return the result of the cast. *VALID_P is set to
5740 indicate whether or not the cast was valid. */
5743 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5744 bool *valid_p, tsubst_flags_t complain)
5750 /* Assume the cast is valid. */
5753 intype = TREE_TYPE (expr);
5755 /* Save casted types in the function's used types hash table. */
5756 used_types_insert (type);
5758 /* [expr.static.cast]
5760 An lvalue of type "cv1 B", where B is a class type, can be cast
5761 to type "reference to cv2 D", where D is a class derived (clause
5762 _class.derived_) from B, if a valid standard conversion from
5763 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5764 same cv-qualification as, or greater cv-qualification than, cv1,
5765 and B is not a virtual base class of D. */
5766 /* We check this case before checking the validity of "TYPE t =
5767 EXPR;" below because for this case:
5770 struct D : public B { D(const B&); };
5772 void f() { static_cast<const D&>(b); }
5774 we want to avoid constructing a new D. The standard is not
5775 completely clear about this issue, but our interpretation is
5776 consistent with other compilers. */
5777 if (TREE_CODE (type) == REFERENCE_TYPE
5778 && CLASS_TYPE_P (TREE_TYPE (type))
5779 && CLASS_TYPE_P (intype)
5780 && (TYPE_REF_IS_RVALUE (type) || real_lvalue_p (expr))
5781 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5782 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5783 build_pointer_type (TYPE_MAIN_VARIANT
5784 (TREE_TYPE (type))))
5786 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5790 /* There is a standard conversion from "D*" to "B*" even if "B"
5791 is ambiguous or inaccessible. If this is really a
5792 static_cast, then we check both for inaccessibility and
5793 ambiguity. However, if this is a static_cast being performed
5794 because the user wrote a C-style cast, then accessibility is
5796 base = lookup_base (TREE_TYPE (type), intype,
5797 c_cast_p ? ba_unique : ba_check,
5800 /* Convert from "B*" to "D*". This function will check that "B"
5801 is not a virtual base of "D". */
5802 expr = build_base_path (MINUS_EXPR, build_address (expr),
5803 base, /*nonnull=*/false);
5804 /* Convert the pointer to a reference -- but then remember that
5805 there are no expressions with reference type in C++. */
5806 return convert_from_reference (cp_fold_convert (type, expr));
5809 /* "An lvalue of type cv1 T1 can be cast to type rvalue reference to
5810 cv2 T2 if cv2 T2 is reference-compatible with cv1 T1 (8.5.3)." */
5811 if (TREE_CODE (type) == REFERENCE_TYPE
5812 && TYPE_REF_IS_RVALUE (type)
5813 && real_lvalue_p (expr)
5814 && reference_related_p (TREE_TYPE (type), intype)
5815 && (c_cast_p || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5817 expr = build_typed_address (expr, type);
5818 return convert_from_reference (expr);
5823 /* Resolve overloaded address here rather than once in
5824 implicit_conversion and again in the inverse code below. */
5825 if (TYPE_PTRMEMFUNC_P (type) && type_unknown_p (expr))
5827 expr = instantiate_type (type, expr, complain);
5828 intype = TREE_TYPE (expr);
5831 /* [expr.static.cast]
5833 An expression e can be explicitly converted to a type T using a
5834 static_cast of the form static_cast<T>(e) if the declaration T
5835 t(e);" is well-formed, for some invented temporary variable
5837 result = perform_direct_initialization_if_possible (type, expr,
5838 c_cast_p, complain);
5841 result = convert_from_reference (result);
5843 /* Ignore any integer overflow caused by the cast. */
5844 result = ignore_overflows (result, orig);
5846 /* [expr.static.cast]
5848 If T is a reference type, the result is an lvalue; otherwise,
5849 the result is an rvalue. */
5850 if (TREE_CODE (type) != REFERENCE_TYPE)
5851 result = rvalue (result);
5855 /* [expr.static.cast]
5857 Any expression can be explicitly converted to type cv void. */
5858 if (TREE_CODE (type) == VOID_TYPE)
5859 return convert_to_void (expr, /*implicit=*/NULL, complain);
5861 /* [expr.static.cast]
5863 The inverse of any standard conversion sequence (clause _conv_),
5864 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5865 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5866 (_conv.bool_) conversions, can be performed explicitly using
5867 static_cast subject to the restriction that the explicit
5868 conversion does not cast away constness (_expr.const.cast_), and
5869 the following additional rules for specific cases: */
5870 /* For reference, the conversions not excluded are: integral
5871 promotions, floating point promotion, integral conversions,
5872 floating point conversions, floating-integral conversions,
5873 pointer conversions, and pointer to member conversions. */
5876 A value of integral _or enumeration_ type can be explicitly
5877 converted to an enumeration type. */
5878 /* The effect of all that is that any conversion between any two
5879 types which are integral, floating, or enumeration types can be
5881 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5882 || SCALAR_FLOAT_TYPE_P (type))
5883 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5884 || SCALAR_FLOAT_TYPE_P (intype)))
5886 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5888 /* Ignore any integer overflow caused by the cast. */
5889 expr = ignore_overflows (expr, orig);
5893 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5894 && CLASS_TYPE_P (TREE_TYPE (type))
5895 && CLASS_TYPE_P (TREE_TYPE (intype))
5896 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5897 (TREE_TYPE (intype))),
5898 build_pointer_type (TYPE_MAIN_VARIANT
5899 (TREE_TYPE (type)))))
5904 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5905 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5906 c_cast_p ? ba_unique : ba_check,
5908 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5911 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5912 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5919 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5920 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5922 if (TYPE_PTRMEM_P (type))
5924 t1 = (build_ptrmem_type
5926 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5927 t2 = (build_ptrmem_type
5929 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5936 if (can_convert (t1, t2) || can_convert (t2, t1))
5939 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5940 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5945 /* [expr.static.cast]
5947 An rvalue of type "pointer to cv void" can be explicitly
5948 converted to a pointer to object type. A value of type pointer
5949 to object converted to "pointer to cv void" and back to the
5950 original pointer type will have its original value. */
5951 if (TREE_CODE (intype) == POINTER_TYPE
5952 && VOID_TYPE_P (TREE_TYPE (intype))
5953 && TYPE_PTROB_P (type))
5956 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5957 return build_nop (type, expr);
5961 return error_mark_node;
5964 /* Return an expression representing static_cast<TYPE>(EXPR). */
5967 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5972 if (type == error_mark_node || expr == error_mark_node)
5973 return error_mark_node;
5975 if (processing_template_decl)
5977 expr = build_min (STATIC_CAST_EXPR, type, expr);
5978 /* We don't know if it will or will not have side effects. */
5979 TREE_SIDE_EFFECTS (expr) = 1;
5980 return convert_from_reference (expr);
5983 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5984 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5985 if (TREE_CODE (type) != REFERENCE_TYPE
5986 && TREE_CODE (expr) == NOP_EXPR
5987 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5988 expr = TREE_OPERAND (expr, 0);
5990 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5995 if (complain & tf_error)
5996 error ("invalid static_cast from type %qT to type %qT",
5997 TREE_TYPE (expr), type);
5998 return error_mark_node;
6001 /* EXPR is an expression with member function or pointer-to-member
6002 function type. TYPE is a pointer type. Converting EXPR to TYPE is
6003 not permitted by ISO C++, but we accept it in some modes. If we
6004 are not in one of those modes, issue a diagnostic. Return the
6005 converted expression. */
6008 convert_member_func_to_ptr (tree type, tree expr)
6013 intype = TREE_TYPE (expr);
6014 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
6015 || TREE_CODE (intype) == METHOD_TYPE);
6017 if (pedantic || warn_pmf2ptr)
6018 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
6019 "converting from %qT to %qT", intype, type);
6021 if (TREE_CODE (intype) == METHOD_TYPE)
6022 expr = build_addr_func (expr);
6023 else if (TREE_CODE (expr) == PTRMEM_CST)
6024 expr = build_address (PTRMEM_CST_MEMBER (expr));
6027 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
6028 decl = build_address (decl);
6029 expr = get_member_function_from_ptrfunc (&decl, expr);
6032 return build_nop (type, expr);
6035 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
6036 If C_CAST_P is true, this reinterpret cast is being done as part of
6037 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
6038 indicate whether or not reinterpret_cast was valid. */
6041 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
6042 bool *valid_p, tsubst_flags_t complain)
6046 /* Assume the cast is invalid. */
6050 if (type == error_mark_node || error_operand_p (expr))
6051 return error_mark_node;
6053 intype = TREE_TYPE (expr);
6055 /* Save casted types in the function's used types hash table. */
6056 used_types_insert (type);
6058 /* [expr.reinterpret.cast]
6059 An lvalue expression of type T1 can be cast to the type
6060 "reference to T2" if an expression of type "pointer to T1" can be
6061 explicitly converted to the type "pointer to T2" using a
6062 reinterpret_cast. */
6063 if (TREE_CODE (type) == REFERENCE_TYPE)
6065 if (! real_lvalue_p (expr))
6067 if (complain & tf_error)
6068 error ("invalid cast of an rvalue expression of type "
6071 return error_mark_node;
6074 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
6075 "B" are related class types; the reinterpret_cast does not
6076 adjust the pointer. */
6077 if (TYPE_PTR_P (intype)
6078 && (complain & tf_warning)
6079 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
6080 COMPARE_BASE | COMPARE_DERIVED)))
6081 warning (0, "casting %qT to %qT does not dereference pointer",
6084 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
6086 if (warn_strict_aliasing > 2)
6087 strict_aliasing_warning (TREE_TYPE (expr), type, expr);
6089 if (expr != error_mark_node)
6090 expr = build_reinterpret_cast_1
6091 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
6093 if (expr != error_mark_node)
6094 /* cp_build_indirect_ref isn't right for rvalue refs. */
6095 expr = convert_from_reference (fold_convert (type, expr));
6099 /* As a G++ extension, we consider conversions from member
6100 functions, and pointers to member functions to
6101 pointer-to-function and pointer-to-void types. If
6102 -Wno-pmf-conversions has not been specified,
6103 convert_member_func_to_ptr will issue an error message. */
6104 if ((TYPE_PTRMEMFUNC_P (intype)
6105 || TREE_CODE (intype) == METHOD_TYPE)
6106 && TYPE_PTR_P (type)
6107 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
6108 || VOID_TYPE_P (TREE_TYPE (type))))
6109 return convert_member_func_to_ptr (type, expr);
6111 /* If the cast is not to a reference type, the lvalue-to-rvalue,
6112 array-to-pointer, and function-to-pointer conversions are
6114 expr = decay_conversion (expr);
6116 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6117 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
6118 if (TREE_CODE (expr) == NOP_EXPR
6119 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
6120 expr = TREE_OPERAND (expr, 0);
6122 if (error_operand_p (expr))
6123 return error_mark_node;
6125 intype = TREE_TYPE (expr);
6127 /* [expr.reinterpret.cast]
6128 A pointer can be converted to any integral type large enough to
6129 hold it. ... A value of type std::nullptr_t can be converted to
6130 an integral type; the conversion has the same meaning and
6131 validity as a conversion of (void*)0 to the integral type. */
6132 if (CP_INTEGRAL_TYPE_P (type)
6133 && (TYPE_PTR_P (intype) || NULLPTR_TYPE_P (intype)))
6135 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
6137 if (complain & tf_error)
6138 permerror (input_location, "cast from %qT to %qT loses precision",
6141 return error_mark_node;
6143 if (NULLPTR_TYPE_P (intype))
6144 return build_int_cst (type, 0);
6146 /* [expr.reinterpret.cast]
6147 A value of integral or enumeration type can be explicitly
6148 converted to a pointer. */
6149 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
6152 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
6153 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
6154 return fold_if_not_in_template (build_nop (type, expr));
6155 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
6156 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
6161 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
6162 /* Warn about possible alignment problems. */
6163 if (STRICT_ALIGNMENT && warn_cast_align
6164 && (complain & tf_warning)
6165 && !VOID_TYPE_P (type)
6166 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
6167 && COMPLETE_TYPE_P (TREE_TYPE (type))
6168 && COMPLETE_TYPE_P (TREE_TYPE (intype))
6169 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
6170 warning (OPT_Wcast_align, "cast from %qT to %qT "
6171 "increases required alignment of target type", intype, type);
6173 /* We need to strip nops here, because the front end likes to
6174 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
6176 if (warn_strict_aliasing <= 2)
6177 strict_aliasing_warning (intype, type, sexpr);
6179 return fold_if_not_in_template (build_nop (type, expr));
6181 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
6182 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
6184 if (pedantic && (complain & tf_warning))
6185 /* Only issue a warning, as we have always supported this
6186 where possible, and it is necessary in some cases. DR 195
6187 addresses this issue, but as of 2004/10/26 is still in
6189 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
6190 return fold_if_not_in_template (build_nop (type, expr));
6192 else if (TREE_CODE (type) == VECTOR_TYPE)
6193 return fold_if_not_in_template (convert_to_vector (type, expr));
6194 else if (TREE_CODE (intype) == VECTOR_TYPE
6195 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
6196 return fold_if_not_in_template (convert_to_integer (type, expr));
6201 if (complain & tf_error)
6202 error ("invalid cast from type %qT to type %qT", intype, type);
6203 return error_mark_node;
6206 return cp_convert (type, expr);
6210 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
6212 if (type == error_mark_node || expr == error_mark_node)
6213 return error_mark_node;
6215 if (processing_template_decl)
6217 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
6219 if (!TREE_SIDE_EFFECTS (t)
6220 && type_dependent_expression_p (expr))
6221 /* There might turn out to be side effects inside expr. */
6222 TREE_SIDE_EFFECTS (t) = 1;
6223 return convert_from_reference (t);
6226 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
6227 /*valid_p=*/NULL, complain);
6230 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
6231 return an appropriate expression. Otherwise, return
6232 error_mark_node. If the cast is not valid, and COMPLAIN is true,
6233 then a diagnostic will be issued. If VALID_P is non-NULL, we are
6234 performing a C-style cast, its value upon return will indicate
6235 whether or not the conversion succeeded. */
6238 build_const_cast_1 (tree dst_type, tree expr, bool complain,
6242 tree reference_type;
6244 /* Callers are responsible for handling error_mark_node as a
6245 destination type. */
6246 gcc_assert (dst_type != error_mark_node);
6247 /* In a template, callers should be building syntactic
6248 representations of casts, not using this machinery. */
6249 gcc_assert (!processing_template_decl);
6251 /* Assume the conversion is invalid. */
6255 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
6258 error ("invalid use of const_cast with type %qT, "
6259 "which is not a pointer, "
6260 "reference, nor a pointer-to-data-member type", dst_type);
6261 return error_mark_node;
6264 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
6267 error ("invalid use of const_cast with type %qT, which is a pointer "
6268 "or reference to a function type", dst_type);
6269 return error_mark_node;
6272 /* Save casted types in the function's used types hash table. */
6273 used_types_insert (dst_type);
6275 src_type = TREE_TYPE (expr);
6276 /* Expressions do not really have reference types. */
6277 if (TREE_CODE (src_type) == REFERENCE_TYPE)
6278 src_type = TREE_TYPE (src_type);
6280 /* [expr.const.cast]
6282 An lvalue of type T1 can be explicitly converted to an lvalue of
6283 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
6284 types) if a pointer to T1 can be explicitly converted to the type
6285 pointer to T2 using a const_cast. */
6286 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
6288 reference_type = dst_type;
6289 if (! real_lvalue_p (expr))
6292 error ("invalid const_cast of an rvalue of type %qT to type %qT",
6293 src_type, dst_type);
6294 return error_mark_node;
6296 dst_type = build_pointer_type (TREE_TYPE (dst_type));
6297 src_type = build_pointer_type (src_type);
6301 reference_type = NULL_TREE;
6302 /* If the destination type is not a reference type, the
6303 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6304 conversions are performed. */
6305 src_type = type_decays_to (src_type);
6306 if (src_type == error_mark_node)
6307 return error_mark_node;
6310 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
6311 && comp_ptr_ttypes_const (dst_type, src_type))
6316 /* This cast is actually a C-style cast. Issue a warning if
6317 the user is making a potentially unsafe cast. */
6318 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
6322 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
6323 complain? tf_warning_or_error : tf_none);
6324 expr = build_nop (reference_type, expr);
6325 return convert_from_reference (expr);
6329 expr = decay_conversion (expr);
6330 /* build_c_cast puts on a NOP_EXPR to make the result not an
6331 lvalue. Strip such NOP_EXPRs if VALUE is being used in
6332 non-lvalue context. */
6333 if (TREE_CODE (expr) == NOP_EXPR
6334 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
6335 expr = TREE_OPERAND (expr, 0);
6336 return build_nop (dst_type, expr);
6341 error ("invalid const_cast from type %qT to type %qT",
6342 src_type, dst_type);
6343 return error_mark_node;
6347 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
6349 if (type == error_mark_node || error_operand_p (expr))
6350 return error_mark_node;
6352 if (processing_template_decl)
6354 tree t = build_min (CONST_CAST_EXPR, type, expr);
6356 if (!TREE_SIDE_EFFECTS (t)
6357 && type_dependent_expression_p (expr))
6358 /* There might turn out to be side effects inside expr. */
6359 TREE_SIDE_EFFECTS (t) = 1;
6360 return convert_from_reference (t);
6363 return build_const_cast_1 (type, expr, complain & tf_error,
6367 /* Like cp_build_c_cast, but for the c-common bits. */
6370 build_c_cast (location_t loc ATTRIBUTE_UNUSED, tree type, tree expr)
6372 return cp_build_c_cast (type, expr, tf_warning_or_error);
6375 /* Build an expression representing an explicit C-style cast to type
6376 TYPE of expression EXPR. */
6379 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
6385 if (type == error_mark_node || error_operand_p (expr))
6386 return error_mark_node;
6388 if (processing_template_decl)
6390 tree t = build_min (CAST_EXPR, type,
6391 tree_cons (NULL_TREE, value, NULL_TREE));
6392 /* We don't know if it will or will not have side effects. */
6393 TREE_SIDE_EFFECTS (t) = 1;
6394 return convert_from_reference (t);
6397 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
6398 'Class') should always be retained, because this information aids
6399 in method lookup. */
6400 if (objc_is_object_ptr (type)
6401 && objc_is_object_ptr (TREE_TYPE (expr)))
6402 return build_nop (type, expr);
6404 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6405 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
6406 if (TREE_CODE (type) != REFERENCE_TYPE
6407 && TREE_CODE (value) == NOP_EXPR
6408 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
6409 value = TREE_OPERAND (value, 0);
6411 if (TREE_CODE (type) == ARRAY_TYPE)
6413 /* Allow casting from T1* to T2[] because Cfront allows it.
6414 NIHCL uses it. It is not valid ISO C++ however. */
6415 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
6417 if (complain & tf_error)
6418 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
6420 return error_mark_node;
6421 type = build_pointer_type (TREE_TYPE (type));
6425 if (complain & tf_error)
6426 error ("ISO C++ forbids casting to an array type %qT", type);
6427 return error_mark_node;
6431 if (TREE_CODE (type) == FUNCTION_TYPE
6432 || TREE_CODE (type) == METHOD_TYPE)
6434 if (complain & tf_error)
6435 error ("invalid cast to function type %qT", type);
6436 return error_mark_node;
6439 if (TREE_CODE (type) == POINTER_TYPE
6440 && TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
6441 /* Casting to an integer of smaller size is an error detected elsewhere. */
6442 && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (value))
6443 /* Don't warn about converting any constant. */
6444 && !TREE_CONSTANT (value))
6445 warning_at (input_location, OPT_Wint_to_pointer_cast,
6446 "cast to pointer from integer of different size");
6448 /* A C-style cast can be a const_cast. */
6449 result = build_const_cast_1 (type, value, /*complain=*/false,
6454 /* Or a static cast. */
6455 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
6456 &valid_p, complain);
6457 /* Or a reinterpret_cast. */
6459 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
6460 &valid_p, complain);
6461 /* The static_cast or reinterpret_cast may be followed by a
6464 /* A valid cast may result in errors if, for example, a
6465 conversion to am ambiguous base class is required. */
6466 && !error_operand_p (result))
6470 /* Non-class rvalues always have cv-unqualified type. */
6471 if (!CLASS_TYPE_P (type))
6472 type = TYPE_MAIN_VARIANT (type);
6473 result_type = TREE_TYPE (result);
6474 if (!CLASS_TYPE_P (result_type))
6475 result_type = TYPE_MAIN_VARIANT (result_type);
6476 /* If the type of RESULT does not match TYPE, perform a
6477 const_cast to make it match. If the static_cast or
6478 reinterpret_cast succeeded, we will differ by at most
6479 cv-qualification, so the follow-on const_cast is guaranteed
6481 if (!same_type_p (non_reference (type), non_reference (result_type)))
6483 result = build_const_cast_1 (type, result, false, &valid_p);
6484 gcc_assert (valid_p);
6489 return error_mark_node;
6492 /* For use from the C common bits. */
6494 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
6495 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
6496 enum tree_code modifycode,
6497 location_t rhs_location ATTRIBUTE_UNUSED, tree rhs,
6498 tree rhs_origtype ATTRIBUTE_UNUSED)
6500 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
6503 /* Build an assignment expression of lvalue LHS from value RHS.
6504 MODIFYCODE is the code for a binary operator that we use
6505 to combine the old value of LHS with RHS to get the new value.
6506 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
6508 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
6511 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6512 tsubst_flags_t complain)
6516 tree lhstype = TREE_TYPE (lhs);
6517 tree olhstype = lhstype;
6518 bool plain_assign = (modifycode == NOP_EXPR);
6520 /* Avoid duplicate error messages from operands that had errors. */
6521 if (error_operand_p (lhs) || error_operand_p (rhs))
6522 return error_mark_node;
6524 /* Handle control structure constructs used as "lvalues". */
6525 switch (TREE_CODE (lhs))
6527 /* Handle --foo = 5; as these are valid constructs in C++. */
6528 case PREDECREMENT_EXPR:
6529 case PREINCREMENT_EXPR:
6530 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6531 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6532 stabilize_reference (TREE_OPERAND (lhs, 0)),
6533 TREE_OPERAND (lhs, 1));
6534 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
6535 modifycode, rhs, complain);
6536 if (newrhs == error_mark_node)
6537 return error_mark_node;
6538 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6540 /* Handle (a, b) used as an "lvalue". */
6542 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6543 modifycode, rhs, complain);
6544 if (newrhs == error_mark_node)
6545 return error_mark_node;
6546 return build2 (COMPOUND_EXPR, lhstype,
6547 TREE_OPERAND (lhs, 0), newrhs);
6550 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6551 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6552 stabilize_reference (TREE_OPERAND (lhs, 0)),
6553 TREE_OPERAND (lhs, 1));
6554 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6556 if (newrhs == error_mark_node)
6557 return error_mark_node;
6558 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6562 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6563 when neither operand has side-effects. */
6564 if (!lvalue_or_else (lhs, lv_assign, complain))
6565 return error_mark_node;
6567 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6568 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6570 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6571 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6573 TREE_OPERAND (lhs, 0),
6574 TREE_OPERAND (lhs, 1)),
6575 TREE_OPERAND (lhs, 0),
6576 TREE_OPERAND (lhs, 1));
6579 /* Handle (a ? b : c) used as an "lvalue". */
6582 /* Produce (a ? (b = rhs) : (c = rhs))
6583 except that the RHS goes through a save-expr
6584 so the code to compute it is only emitted once. */
6586 tree preeval = NULL_TREE;
6588 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6590 if (complain & tf_error)
6591 error ("void value not ignored as it ought to be");
6592 return error_mark_node;
6595 rhs = stabilize_expr (rhs, &preeval);
6597 /* Check this here to avoid odd errors when trying to convert
6598 a throw to the type of the COND_EXPR. */
6599 if (!lvalue_or_else (lhs, lv_assign, complain))
6600 return error_mark_node;
6602 cond = build_conditional_expr
6603 (TREE_OPERAND (lhs, 0),
6604 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6605 modifycode, rhs, complain),
6606 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6607 modifycode, rhs, complain),
6610 if (cond == error_mark_node)
6612 /* Make sure the code to compute the rhs comes out
6613 before the split. */
6615 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6623 if (modifycode == INIT_EXPR)
6625 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6626 /* Do the default thing. */;
6627 else if (TREE_CODE (rhs) == CONSTRUCTOR)
6629 /* Compound literal. */
6630 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6631 /* Call convert to generate an error; see PR 11063. */
6632 rhs = convert (lhstype, rhs);
6633 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6634 TREE_SIDE_EFFECTS (result) = 1;
6637 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6638 /* Do the default thing. */;
6641 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6642 result = build_special_member_call (lhs, complete_ctor_identifier,
6643 &rhs_vec, lhstype, LOOKUP_NORMAL,
6645 release_tree_vector (rhs_vec);
6646 if (result == NULL_TREE)
6647 return error_mark_node;
6653 lhs = require_complete_type (lhs);
6654 if (lhs == error_mark_node)
6655 return error_mark_node;
6657 if (modifycode == NOP_EXPR)
6659 /* `operator=' is not an inheritable operator. */
6660 if (! MAYBE_CLASS_TYPE_P (lhstype))
6661 /* Do the default thing. */;
6664 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6665 lhs, rhs, make_node (NOP_EXPR),
6666 /*overloaded_p=*/NULL,
6668 if (result == NULL_TREE)
6669 return error_mark_node;
6676 /* A binary op has been requested. Combine the old LHS
6677 value with the RHS producing the value we should actually
6678 store into the LHS. */
6679 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6680 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6681 || MAYBE_CLASS_TYPE_P (lhstype)));
6683 lhs = stabilize_reference (lhs);
6684 newrhs = cp_build_binary_op (input_location,
6685 modifycode, lhs, rhs,
6687 if (newrhs == error_mark_node)
6689 if (complain & tf_error)
6690 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6691 TREE_TYPE (lhs), TREE_TYPE (rhs));
6692 return error_mark_node;
6695 /* Now it looks like a plain assignment. */
6696 modifycode = NOP_EXPR;
6698 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6699 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6702 /* The left-hand side must be an lvalue. */
6703 if (!lvalue_or_else (lhs, lv_assign, complain))
6704 return error_mark_node;
6706 /* Warn about modifying something that is `const'. Don't warn if
6707 this is initialization. */
6708 if (modifycode != INIT_EXPR
6709 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6710 /* Functions are not modifiable, even though they are
6712 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6713 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6714 /* If it's an aggregate and any field is const, then it is
6715 effectively const. */
6716 || (CLASS_TYPE_P (lhstype)
6717 && C_TYPE_FIELDS_READONLY (lhstype))))
6719 if (complain & tf_error)
6720 readonly_error (lhs, REK_ASSIGNMENT);
6722 return error_mark_node;
6725 /* If storing into a structure or union member, it may have been given a
6726 lowered bitfield type. We need to convert to the declared type first,
6727 so retrieve it now. */
6729 olhstype = unlowered_expr_type (lhs);
6731 /* Convert new value to destination type. */
6733 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6737 if (BRACE_ENCLOSED_INITIALIZER_P (newrhs))
6739 if (modifycode != INIT_EXPR)
6741 if (complain & tf_error)
6742 error ("assigning to an array from an initializer list");
6743 return error_mark_node;
6745 if (check_array_initializer (lhs, lhstype, newrhs))
6746 return error_mark_node;
6747 newrhs = digest_init (lhstype, newrhs);
6750 else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6751 TYPE_MAIN_VARIANT (TREE_TYPE (newrhs))))
6753 if (complain & tf_error)
6754 error ("incompatible types in assignment of %qT to %qT",
6755 TREE_TYPE (rhs), lhstype);
6756 return error_mark_node;
6759 /* Allow array assignment in compiler-generated code. */
6760 else if (!current_function_decl
6761 || !DECL_ARTIFICIAL (current_function_decl))
6763 /* This routine is used for both initialization and assignment.
6764 Make sure the diagnostic message differentiates the context. */
6765 if (complain & tf_error)
6767 if (modifycode == INIT_EXPR)
6768 error ("array used as initializer");
6770 error ("invalid array assignment");
6772 return error_mark_node;
6775 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6776 ? 1 + (modifycode != INIT_EXPR): 0;
6777 return build_vec_init (lhs, NULL_TREE, newrhs,
6778 /*explicit_value_init_p=*/false,
6779 from_array, complain);
6782 if (modifycode == INIT_EXPR)
6783 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6784 LOOKUP_ONLYCONVERTING. */
6785 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6786 ICR_INIT, NULL_TREE, 0,
6789 newrhs = convert_for_assignment (olhstype, newrhs, ICR_ASSIGN,
6790 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6792 if (!same_type_p (lhstype, olhstype))
6793 newrhs = cp_convert_and_check (lhstype, newrhs);
6795 if (modifycode != INIT_EXPR)
6797 if (TREE_CODE (newrhs) == CALL_EXPR
6798 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6799 newrhs = build_cplus_new (lhstype, newrhs);
6801 /* Can't initialize directly from a TARGET_EXPR, since that would
6802 cause the lhs to be constructed twice, and possibly result in
6803 accidental self-initialization. So we force the TARGET_EXPR to be
6804 expanded without a target. */
6805 if (TREE_CODE (newrhs) == TARGET_EXPR)
6806 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6807 TREE_OPERAND (newrhs, 0));
6810 if (newrhs == error_mark_node)
6811 return error_mark_node;
6813 if (c_dialect_objc () && flag_objc_gc)
6815 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6821 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6822 lhstype, lhs, newrhs);
6824 TREE_SIDE_EFFECTS (result) = 1;
6826 TREE_NO_WARNING (result) = 1;
6832 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6833 tsubst_flags_t complain)
6835 if (processing_template_decl)
6836 return build_min_nt (MODOP_EXPR, lhs,
6837 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6839 if (modifycode != NOP_EXPR)
6841 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6842 make_node (modifycode),
6843 /*overloaded_p=*/NULL,
6847 TREE_NO_WARNING (rval) = 1;
6851 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6854 /* Helper function for get_delta_difference which assumes FROM is a base
6855 class of TO. Returns a delta for the conversion of pointer-to-member
6856 of FROM to pointer-to-member of TO. If the conversion is invalid,
6857 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6858 If C_CAST_P is true, this conversion is taking place as part of a C-style
6862 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6867 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6868 if (kind == bk_inaccessible || kind == bk_ambig)
6870 error (" in pointer to member function conversion");
6871 return size_zero_node;
6875 if (kind != bk_via_virtual)
6876 return BINFO_OFFSET (binfo);
6878 /* FROM is a virtual base class of TO. Issue an error or warning
6879 depending on whether or not this is a reinterpret cast. */
6881 error ("pointer to member conversion via virtual base %qT",
6882 BINFO_TYPE (binfo_from_vbase (binfo)));
6884 return size_zero_node;
6891 /* Get difference in deltas for different pointer to member function
6892 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6893 the conversion is invalid, the constant is zero. If
6894 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6895 If C_CAST_P is true this conversion is taking place as part of a
6898 Note that the naming of FROM and TO is kind of backwards; the return
6899 value is what we add to a TO in order to get a FROM. They are named
6900 this way because we call this function to find out how to convert from
6901 a pointer to member of FROM to a pointer to member of TO. */
6904 get_delta_difference (tree from, tree to,
6905 bool allow_inverse_p,
6910 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6911 /* Pointer to member of incomplete class is permitted*/
6912 result = size_zero_node;
6914 result = get_delta_difference_1 (from, to, c_cast_p);
6918 if (!allow_inverse_p)
6920 error_not_base_type (from, to);
6921 error (" in pointer to member conversion");
6922 result = size_zero_node;
6926 result = get_delta_difference_1 (to, from, c_cast_p);
6929 result = size_diffop_loc (input_location,
6930 size_zero_node, result);
6933 error_not_base_type (from, to);
6934 error (" in pointer to member conversion");
6935 result = size_zero_node;
6940 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6944 /* Return a constructor for the pointer-to-member-function TYPE using
6945 the other components as specified. */
6948 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6953 VEC(constructor_elt, gc) *v;
6955 /* Pull the FIELD_DECLs out of the type. */
6956 pfn_field = TYPE_FIELDS (type);
6957 delta_field = TREE_CHAIN (pfn_field);
6959 /* Make sure DELTA has the type we want. */
6960 delta = convert_and_check (delta_type_node, delta);
6962 /* Convert to the correct target type if necessary. */
6963 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6965 /* Finish creating the initializer. */
6966 v = VEC_alloc(constructor_elt, gc, 2);
6967 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6968 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6969 u = build_constructor (type, v);
6970 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6971 TREE_STATIC (u) = (TREE_CONSTANT (u)
6972 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6974 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6979 /* Build a constructor for a pointer to member function. It can be
6980 used to initialize global variables, local variable, or used
6981 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6984 If FORCE is nonzero, then force this conversion, even if
6985 we would rather not do it. Usually set when using an explicit
6986 cast. A C-style cast is being processed iff C_CAST_P is true.
6988 Return error_mark_node, if something goes wrong. */
6991 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6997 if (error_operand_p (pfn))
6998 return error_mark_node;
7000 pfn_type = TREE_TYPE (pfn);
7001 to_type = build_ptrmemfunc_type (type);
7003 /* Handle multiple conversions of pointer to member functions. */
7004 if (TYPE_PTRMEMFUNC_P (pfn_type))
7006 tree delta = NULL_TREE;
7007 tree npfn = NULL_TREE;
7011 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
7012 error ("invalid conversion to type %qT from type %qT",
7015 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
7016 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
7020 /* We don't have to do any conversion to convert a
7021 pointer-to-member to its own type. But, we don't want to
7022 just return a PTRMEM_CST if there's an explicit cast; that
7023 cast should make the expression an invalid template argument. */
7024 if (TREE_CODE (pfn) != PTRMEM_CST)
7026 if (same_type_p (to_type, pfn_type))
7028 else if (integer_zerop (n))
7029 return build_reinterpret_cast (to_type, pfn,
7030 tf_warning_or_error);
7033 if (TREE_SIDE_EFFECTS (pfn))
7034 pfn = save_expr (pfn);
7036 /* Obtain the function pointer and the current DELTA. */
7037 if (TREE_CODE (pfn) == PTRMEM_CST)
7038 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
7041 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
7042 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
7045 /* Just adjust the DELTA field. */
7046 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7047 (TREE_TYPE (delta), ptrdiff_type_node));
7048 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
7049 n = cp_build_binary_op (input_location,
7050 LSHIFT_EXPR, n, integer_one_node,
7051 tf_warning_or_error);
7052 delta = cp_build_binary_op (input_location,
7053 PLUS_EXPR, delta, n, tf_warning_or_error);
7054 return build_ptrmemfunc1 (to_type, delta, npfn);
7057 /* Handle null pointer to member function conversions. */
7058 if (null_ptr_cst_p (pfn))
7060 pfn = build_c_cast (input_location, type, integer_zero_node);
7061 return build_ptrmemfunc1 (to_type,
7066 if (type_unknown_p (pfn))
7067 return instantiate_type (type, pfn, tf_warning_or_error);
7069 fn = TREE_OPERAND (pfn, 0);
7070 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
7071 /* In a template, we will have preserved the
7073 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
7074 return make_ptrmem_cst (to_type, fn);
7077 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
7080 ??? There is no consistency as to the types returned for the above
7081 values. Some code acts as if it were a sizetype and some as if it were
7082 integer_type_node. */
7085 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
7087 tree type = TREE_TYPE (cst);
7088 tree fn = PTRMEM_CST_MEMBER (cst);
7089 tree ptr_class, fn_class;
7091 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7093 /* The class that the function belongs to. */
7094 fn_class = DECL_CONTEXT (fn);
7096 /* The class that we're creating a pointer to member of. */
7097 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
7099 /* First, calculate the adjustment to the function's class. */
7100 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
7103 if (!DECL_VIRTUAL_P (fn))
7104 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
7107 /* If we're dealing with a virtual function, we have to adjust 'this'
7108 again, to point to the base which provides the vtable entry for
7109 fn; the call will do the opposite adjustment. */
7110 tree orig_class = DECL_CONTEXT (fn);
7111 tree binfo = binfo_or_else (orig_class, fn_class);
7112 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
7113 *delta, BINFO_OFFSET (binfo));
7114 *delta = fold_if_not_in_template (*delta);
7116 /* We set PFN to the vtable offset at which the function can be
7117 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
7118 case delta is shifted left, and then incremented). */
7119 *pfn = DECL_VINDEX (fn);
7120 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
7121 TYPE_SIZE_UNIT (vtable_entry_type));
7122 *pfn = fold_if_not_in_template (*pfn);
7124 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
7126 case ptrmemfunc_vbit_in_pfn:
7127 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
7129 *pfn = fold_if_not_in_template (*pfn);
7132 case ptrmemfunc_vbit_in_delta:
7133 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
7134 *delta, integer_one_node);
7135 *delta = fold_if_not_in_template (*delta);
7136 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
7137 *delta, integer_one_node);
7138 *delta = fold_if_not_in_template (*delta);
7145 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
7146 *pfn = fold_if_not_in_template (*pfn);
7150 /* Return an expression for PFN from the pointer-to-member function
7154 pfn_from_ptrmemfunc (tree t)
7156 if (TREE_CODE (t) == PTRMEM_CST)
7161 expand_ptrmemfunc_cst (t, &delta, &pfn);
7166 return build_ptrmemfunc_access_expr (t, pfn_identifier);
7169 /* Return an expression for DELTA from the pointer-to-member function
7173 delta_from_ptrmemfunc (tree t)
7175 if (TREE_CODE (t) == PTRMEM_CST)
7180 expand_ptrmemfunc_cst (t, &delta, &pfn);
7185 return build_ptrmemfunc_access_expr (t, delta_identifier);
7188 /* Convert value RHS to type TYPE as preparation for an assignment to
7189 an lvalue of type TYPE. ERRTYPE indicates what kind of error the
7190 implicit conversion is. If FNDECL is non-NULL, we are doing the
7191 conversion in order to pass the PARMNUMth argument of FNDECL.
7192 If FNDECL is NULL, we are doing the conversion in function pointer
7193 argument passing, conversion in initialization, etc. */
7196 convert_for_assignment (tree type, tree rhs,
7197 impl_conv_rhs errtype, tree fndecl, int parmnum,
7198 tsubst_flags_t complain, int flags)
7201 enum tree_code coder;
7203 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
7204 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
7205 rhs = TREE_OPERAND (rhs, 0);
7207 rhstype = TREE_TYPE (rhs);
7208 coder = TREE_CODE (rhstype);
7210 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
7211 && vector_types_convertible_p (type, rhstype, true))
7212 return convert (type, rhs);
7214 if (rhs == error_mark_node || rhstype == error_mark_node)
7215 return error_mark_node;
7216 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
7217 return error_mark_node;
7219 /* The RHS of an assignment cannot have void type. */
7220 if (coder == VOID_TYPE)
7222 if (complain & tf_error)
7223 error ("void value not ignored as it ought to be");
7224 return error_mark_node;
7227 /* Simplify the RHS if possible. */
7228 if (TREE_CODE (rhs) == CONST_DECL)
7229 rhs = DECL_INITIAL (rhs);
7231 if (c_dialect_objc ())
7235 tree rname = fndecl;
7246 selector = objc_message_selector ();
7248 if (selector && parmno > 1)
7255 if (objc_compare_types (type, rhstype, parmno, rname))
7256 return convert (type, rhs);
7261 The expression is implicitly converted (clause _conv_) to the
7262 cv-unqualified type of the left operand.
7264 We allow bad conversions here because by the time we get to this point
7265 we are committed to doing the conversion. If we end up doing a bad
7266 conversion, convert_like will complain. */
7267 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
7269 /* When -Wno-pmf-conversions is use, we just silently allow
7270 conversions from pointers-to-members to plain pointers. If
7271 the conversion doesn't work, cp_convert will complain. */
7273 && TYPE_PTR_P (type)
7274 && TYPE_PTRMEMFUNC_P (rhstype))
7275 rhs = cp_convert (strip_top_quals (type), rhs);
7278 if (complain & tf_error)
7280 /* If the right-hand side has unknown type, then it is an
7281 overloaded function. Call instantiate_type to get error
7283 if (rhstype == unknown_type_node)
7284 instantiate_type (type, rhs, tf_warning_or_error);
7286 error ("cannot convert %qT to %qT for argument %qP to %qD",
7287 rhstype, type, parmnum, fndecl);
7291 case ICR_DEFAULT_ARGUMENT:
7292 error ("cannot convert %qT to %qT in default argument",
7296 error ("cannot convert %qT to %qT in argument passing",
7299 case ICR_CONVERTING:
7300 error ("cannot convert %qT to %qT",
7304 error ("cannot convert %qT to %qT in initialization",
7308 error ("cannot convert %qT to %qT in return",
7312 error ("cannot convert %qT to %qT in assignment",
7319 return error_mark_node;
7322 if (warn_missing_format_attribute)
7324 const enum tree_code codel = TREE_CODE (type);
7325 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
7327 && check_missing_format_attribute (type, rhstype)
7328 && (complain & tf_warning))
7332 case ICR_DEFAULT_ARGUMENT:
7334 warning (OPT_Wmissing_format_attribute,
7335 "parameter %qP of %qD might be a candidate "
7336 "for a format attribute", parmnum, fndecl);
7338 warning (OPT_Wmissing_format_attribute,
7339 "parameter might be a candidate "
7340 "for a format attribute");
7342 case ICR_CONVERTING:
7343 warning (OPT_Wmissing_format_attribute,
7344 "target of conversion might be might be a candidate "
7345 "for a format attribute");
7348 warning (OPT_Wmissing_format_attribute,
7349 "target of initialization might be a candidate "
7350 "for a format attribute");
7353 warning (OPT_Wmissing_format_attribute,
7354 "return type might be a candidate "
7355 "for a format attribute");
7358 warning (OPT_Wmissing_format_attribute,
7359 "left-hand side of assignment might be a candidate "
7360 "for a format attribute");
7367 /* If -Wparentheses, warn about a = b = c when a has type bool and b
7369 if (warn_parentheses
7370 && TREE_CODE (type) == BOOLEAN_TYPE
7371 && TREE_CODE (rhs) == MODIFY_EXPR
7372 && !TREE_NO_WARNING (rhs)
7373 && TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE
7374 && (complain & tf_warning))
7376 location_t loc = EXPR_HAS_LOCATION (rhs)
7377 ? EXPR_LOCATION (rhs) : input_location;
7379 warning_at (loc, OPT_Wparentheses,
7380 "suggest parentheses around assignment used as truth value");
7381 TREE_NO_WARNING (rhs) = 1;
7384 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
7388 /* Convert RHS to be of type TYPE.
7389 If EXP is nonzero, it is the target of the initialization.
7390 ERRTYPE indicates what kind of error the implicit conversion is.
7392 Two major differences between the behavior of
7393 `convert_for_assignment' and `convert_for_initialization'
7394 are that references are bashed in the former, while
7395 copied in the latter, and aggregates are assigned in
7396 the former (operator=) while initialized in the
7399 If using constructor make sure no conversion operator exists, if one does
7400 exist, an ambiguity exists.
7402 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
7405 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
7406 impl_conv_rhs errtype, tree fndecl, int parmnum,
7407 tsubst_flags_t complain)
7409 enum tree_code codel = TREE_CODE (type);
7411 enum tree_code coder;
7413 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
7414 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
7415 if (TREE_CODE (rhs) == NOP_EXPR
7416 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
7417 && codel != REFERENCE_TYPE)
7418 rhs = TREE_OPERAND (rhs, 0);
7420 if (type == error_mark_node
7421 || rhs == error_mark_node
7422 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
7423 return error_mark_node;
7425 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
7426 && TREE_CODE (type) != ARRAY_TYPE
7427 && (TREE_CODE (type) != REFERENCE_TYPE
7428 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
7429 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
7430 && (TREE_CODE (type) != REFERENCE_TYPE
7431 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
7432 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
7433 rhs = decay_conversion (rhs);
7435 rhstype = TREE_TYPE (rhs);
7436 coder = TREE_CODE (rhstype);
7438 if (coder == ERROR_MARK)
7439 return error_mark_node;
7441 /* We accept references to incomplete types, so we can
7442 return here before checking if RHS is of complete type. */
7444 if (codel == REFERENCE_TYPE)
7446 /* This should eventually happen in convert_arguments. */
7447 int savew = 0, savee = 0;
7450 savew = warningcount, savee = errorcount;
7451 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
7452 /*cleanup=*/NULL, complain);
7455 if (warningcount > savew)
7456 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
7457 else if (errorcount > savee)
7458 error ("in passing argument %P of %q+D", parmnum, fndecl);
7464 exp = require_complete_type (exp);
7465 if (exp == error_mark_node)
7466 return error_mark_node;
7468 rhstype = non_reference (rhstype);
7470 type = complete_type (type);
7472 if (DIRECT_INIT_EXPR_P (type, rhs))
7473 /* Don't try to do copy-initialization if we already have
7474 direct-initialization. */
7477 if (MAYBE_CLASS_TYPE_P (type))
7478 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
7480 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
7484 /* If RETVAL is the address of, or a reference to, a local variable or
7485 temporary give an appropriate warning. */
7488 maybe_warn_about_returning_address_of_local (tree retval)
7490 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
7491 tree whats_returned = retval;
7495 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
7496 whats_returned = TREE_OPERAND (whats_returned, 1);
7497 else if (CONVERT_EXPR_P (whats_returned)
7498 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
7499 whats_returned = TREE_OPERAND (whats_returned, 0);
7504 if (TREE_CODE (whats_returned) != ADDR_EXPR)
7506 whats_returned = TREE_OPERAND (whats_returned, 0);
7508 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7510 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
7511 || TREE_CODE (whats_returned) == TARGET_EXPR)
7513 warning (0, "returning reference to temporary");
7516 if (TREE_CODE (whats_returned) == VAR_DECL
7517 && DECL_NAME (whats_returned)
7518 && TEMP_NAME_P (DECL_NAME (whats_returned)))
7520 warning (0, "reference to non-lvalue returned");
7525 while (TREE_CODE (whats_returned) == COMPONENT_REF
7526 || TREE_CODE (whats_returned) == ARRAY_REF)
7527 whats_returned = TREE_OPERAND (whats_returned, 0);
7529 if (DECL_P (whats_returned)
7530 && DECL_NAME (whats_returned)
7531 && DECL_FUNCTION_SCOPE_P (whats_returned)
7532 && !(TREE_STATIC (whats_returned)
7533 || TREE_PUBLIC (whats_returned)))
7535 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7536 warning (0, "reference to local variable %q+D returned",
7539 warning (0, "address of local variable %q+D returned",
7545 /* Check that returning RETVAL from the current function is valid.
7546 Return an expression explicitly showing all conversions required to
7547 change RETVAL into the function return type, and to assign it to
7548 the DECL_RESULT for the function. Set *NO_WARNING to true if
7549 code reaches end of non-void function warning shouldn't be issued
7550 on this RETURN_EXPR. */
7553 check_return_expr (tree retval, bool *no_warning)
7556 /* The type actually returned by the function, after any
7559 int fn_returns_value_p;
7560 bool named_return_value_okay_p;
7562 *no_warning = false;
7564 /* A `volatile' function is one that isn't supposed to return, ever.
7565 (This is a G++ extension, used to get better code for functions
7566 that call the `volatile' function.) */
7567 if (TREE_THIS_VOLATILE (current_function_decl))
7568 warning (0, "function declared %<noreturn%> has a %<return%> statement");
7570 /* Check for various simple errors. */
7571 if (DECL_DESTRUCTOR_P (current_function_decl))
7574 error ("returning a value from a destructor");
7577 else if (DECL_CONSTRUCTOR_P (current_function_decl))
7579 if (in_function_try_handler)
7580 /* If a return statement appears in a handler of the
7581 function-try-block of a constructor, the program is ill-formed. */
7582 error ("cannot return from a handler of a function-try-block of a constructor");
7584 /* You can't return a value from a constructor. */
7585 error ("returning a value from a constructor");
7589 /* As an extension, deduce lambda return type from a return statement
7590 anywhere in the body. */
7591 if (retval && LAMBDA_FUNCTION_P (current_function_decl))
7593 tree lambda = CLASSTYPE_LAMBDA_EXPR (current_class_type);
7594 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
7596 tree type = lambda_return_type (retval);
7597 tree oldtype = LAMBDA_EXPR_RETURN_TYPE (lambda);
7599 if (VOID_TYPE_P (type))
7601 else if (oldtype == NULL_TREE)
7603 pedwarn (input_location, OPT_pedantic, "lambda return type "
7604 "can only be deduced when the return statement is "
7605 "the only statement in the function body");
7606 apply_lambda_return_type (lambda, type);
7608 else if (!same_type_p (type, oldtype))
7609 error ("inconsistent types %qT and %qT deduced for "
7610 "lambda return type", type, oldtype);
7614 if (processing_template_decl)
7616 current_function_returns_value = 1;
7617 if (check_for_bare_parameter_packs (retval))
7618 retval = error_mark_node;
7622 /* When no explicit return-value is given in a function with a named
7623 return value, the named return value is used. */
7624 result = DECL_RESULT (current_function_decl);
7625 valtype = TREE_TYPE (result);
7626 gcc_assert (valtype != NULL_TREE);
7627 fn_returns_value_p = !VOID_TYPE_P (valtype);
7628 if (!retval && DECL_NAME (result) && fn_returns_value_p)
7631 /* Check for a return statement with no return value in a function
7632 that's supposed to return a value. */
7633 if (!retval && fn_returns_value_p)
7635 permerror (input_location, "return-statement with no value, in function returning %qT",
7637 /* Clear this, so finish_function won't say that we reach the
7638 end of a non-void function (which we don't, we gave a
7640 current_function_returns_null = 0;
7641 /* And signal caller that TREE_NO_WARNING should be set on the
7642 RETURN_EXPR to avoid control reaches end of non-void function
7643 warnings in tree-cfg.c. */
7646 /* Check for a return statement with a value in a function that
7647 isn't supposed to return a value. */
7648 else if (retval && !fn_returns_value_p)
7650 if (VOID_TYPE_P (TREE_TYPE (retval)))
7651 /* You can return a `void' value from a function of `void'
7652 type. In that case, we have to evaluate the expression for
7653 its side-effects. */
7654 finish_expr_stmt (retval);
7656 permerror (input_location, "return-statement with a value, in function "
7657 "returning 'void'");
7658 current_function_returns_null = 1;
7660 /* There's really no value to return, after all. */
7664 /* Remember that this function can sometimes return without a
7666 current_function_returns_null = 1;
7668 /* Remember that this function did return a value. */
7669 current_function_returns_value = 1;
7671 /* Check for erroneous operands -- but after giving ourselves a
7672 chance to provide an error about returning a value from a void
7674 if (error_operand_p (retval))
7676 current_function_return_value = error_mark_node;
7677 return error_mark_node;
7680 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7681 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7682 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7683 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7685 && retval && null_ptr_cst_p (retval))
7686 warning (0, "%<operator new%> must not return NULL unless it is "
7687 "declared %<throw()%> (or -fcheck-new is in effect)");
7689 /* Effective C++ rule 15. See also start_function. */
7691 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7695 /* The function return type must be a reference to the current
7697 if (TREE_CODE (valtype) == REFERENCE_TYPE
7698 && same_type_ignoring_top_level_qualifiers_p
7699 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7701 /* Returning '*this' is obviously OK. */
7702 if (retval == current_class_ref)
7704 /* If we are calling a function whose return type is the same of
7705 the current class reference, it is ok. */
7706 else if (TREE_CODE (retval) == INDIRECT_REF
7707 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7712 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7715 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7717 [...] For a function with a class return type, if the expression
7718 in the return statement is the name of a local object, and the cv-
7719 unqualified type of the local object is the same as the function
7720 return type, an implementation is permitted to omit creating the tem-
7721 porary object to hold the function return value [...]
7723 So, if this is a value-returning function that always returns the same
7724 local variable, remember it.
7726 It might be nice to be more flexible, and choose the first suitable
7727 variable even if the function sometimes returns something else, but
7728 then we run the risk of clobbering the variable we chose if the other
7729 returned expression uses the chosen variable somehow. And people expect
7730 this restriction, anyway. (jason 2000-11-19)
7732 See finish_function and finalize_nrv for the rest of this optimization. */
7734 named_return_value_okay_p =
7735 (retval != NULL_TREE
7736 /* Must be a local, automatic variable. */
7737 && TREE_CODE (retval) == VAR_DECL
7738 && DECL_CONTEXT (retval) == current_function_decl
7739 && ! TREE_STATIC (retval)
7740 && ! DECL_ANON_UNION_VAR_P (retval)
7741 && (DECL_ALIGN (retval)
7742 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7743 /* The cv-unqualified type of the returned value must be the
7744 same as the cv-unqualified return type of the
7746 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7748 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7749 /* And the returned value must be non-volatile. */
7750 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7752 if (fn_returns_value_p && flag_elide_constructors)
7754 if (named_return_value_okay_p
7755 && (current_function_return_value == NULL_TREE
7756 || current_function_return_value == retval))
7757 current_function_return_value = retval;
7759 current_function_return_value = error_mark_node;
7762 /* We don't need to do any conversions when there's nothing being
7767 /* Do any required conversions. */
7768 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7769 /* No conversions are required. */
7773 /* The type the function is declared to return. */
7774 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7775 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7777 /* The functype's return type will have been set to void, if it
7778 was an incomplete type. Just treat this as 'return;' */
7779 if (VOID_TYPE_P (functype))
7780 return error_mark_node;
7782 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7783 treated as an rvalue for the purposes of overload resolution to
7784 favor move constructors over copy constructors. */
7785 if ((cxx_dialect != cxx98)
7786 && named_return_value_okay_p
7787 /* The variable must not have the `volatile' qualifier. */
7788 && !CP_TYPE_VOLATILE_P (TREE_TYPE (retval))
7789 /* The return type must be a class type. */
7790 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7791 flags = flags | LOOKUP_PREFER_RVALUE;
7793 /* First convert the value to the function's return type, then
7794 to the type of return value's location to handle the
7795 case that functype is smaller than the valtype. */
7796 retval = convert_for_initialization
7797 (NULL_TREE, functype, retval, flags, ICR_RETURN, NULL_TREE, 0,
7798 tf_warning_or_error);
7799 retval = convert (valtype, retval);
7801 /* If the conversion failed, treat this just like `return;'. */
7802 if (retval == error_mark_node)
7804 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7805 else if (! cfun->returns_struct
7806 && TREE_CODE (retval) == TARGET_EXPR
7807 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7808 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7809 TREE_OPERAND (retval, 0));
7811 maybe_warn_about_returning_address_of_local (retval);
7814 /* Actually copy the value returned into the appropriate location. */
7815 if (retval && retval != result)
7816 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7822 /* Returns nonzero if the pointer-type FROM can be converted to the
7823 pointer-type TO via a qualification conversion. If CONSTP is -1,
7824 then we return nonzero if the pointers are similar, and the
7825 cv-qualification signature of FROM is a proper subset of that of TO.
7827 If CONSTP is positive, then all outer pointers have been
7831 comp_ptr_ttypes_real (tree to, tree from, int constp)
7833 bool to_more_cv_qualified = false;
7834 bool is_opaque_pointer = false;
7836 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7838 if (TREE_CODE (to) != TREE_CODE (from))
7841 if (TREE_CODE (from) == OFFSET_TYPE
7842 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7843 TYPE_OFFSET_BASETYPE (to)))
7846 /* Const and volatile mean something different for function types,
7847 so the usual checks are not appropriate. */
7848 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7850 /* In Objective-C++, some types may have been 'volatilized' by
7851 the compiler for EH; when comparing them here, the volatile
7852 qualification must be ignored. */
7853 bool objc_quals_match = objc_type_quals_match (to, from);
7855 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7858 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7862 to_more_cv_qualified = true;
7866 constp &= TYPE_READONLY (to);
7869 if (TREE_CODE (to) == VECTOR_TYPE)
7870 is_opaque_pointer = vector_targets_convertible_p (to, from);
7872 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7873 return ((constp >= 0 || to_more_cv_qualified)
7874 && (is_opaque_pointer
7875 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7879 /* When comparing, say, char ** to char const **, this function takes
7880 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7881 types to this function. */
7884 comp_ptr_ttypes (tree to, tree from)
7886 return comp_ptr_ttypes_real (to, from, 1);
7889 /* Returns true iff FNTYPE is a non-class type that involves
7890 error_mark_node. We can get FUNCTION_TYPE with buried error_mark_node
7891 if a parameter type is ill-formed. */
7894 error_type_p (const_tree type)
7898 switch (TREE_CODE (type))
7904 case REFERENCE_TYPE:
7906 return error_type_p (TREE_TYPE (type));
7910 if (error_type_p (TREE_TYPE (type)))
7912 for (t = TYPE_ARG_TYPES (type); t; t = TREE_CHAIN (t))
7913 if (error_type_p (TREE_VALUE (t)))
7918 if (TYPE_PTRMEMFUNC_P (type))
7919 return error_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type));
7927 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7928 type or inheritance-related types, regardless of cv-quals. */
7931 ptr_reasonably_similar (const_tree to, const_tree from)
7933 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7935 /* Any target type is similar enough to void. */
7936 if (TREE_CODE (to) == VOID_TYPE)
7937 return !error_type_p (from);
7938 if (TREE_CODE (from) == VOID_TYPE)
7939 return !error_type_p (to);
7941 if (TREE_CODE (to) != TREE_CODE (from))
7944 if (TREE_CODE (from) == OFFSET_TYPE
7945 && comptypes (TYPE_OFFSET_BASETYPE (to),
7946 TYPE_OFFSET_BASETYPE (from),
7947 COMPARE_BASE | COMPARE_DERIVED))
7950 if (TREE_CODE (to) == VECTOR_TYPE
7951 && vector_types_convertible_p (to, from, false))
7954 if (TREE_CODE (to) == INTEGER_TYPE
7955 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7958 if (TREE_CODE (to) == FUNCTION_TYPE)
7959 return !error_type_p (to) && !error_type_p (from);
7961 if (TREE_CODE (to) != POINTER_TYPE)
7963 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7964 COMPARE_BASE | COMPARE_DERIVED);
7968 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7969 pointer-to-member types) are the same, ignoring cv-qualification at
7973 comp_ptr_ttypes_const (tree to, tree from)
7975 bool is_opaque_pointer = false;
7977 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7979 if (TREE_CODE (to) != TREE_CODE (from))
7982 if (TREE_CODE (from) == OFFSET_TYPE
7983 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7984 TYPE_OFFSET_BASETYPE (to)))
7987 if (TREE_CODE (to) == VECTOR_TYPE)
7988 is_opaque_pointer = vector_targets_convertible_p (to, from);
7990 if (TREE_CODE (to) != POINTER_TYPE)
7991 return (is_opaque_pointer
7992 || same_type_ignoring_top_level_qualifiers_p (to, from));
7996 /* Returns the type qualifiers for this type, including the qualifiers on the
7997 elements for an array type. */
8000 cp_type_quals (const_tree type)
8003 /* This CONST_CAST is okay because strip_array_types returns its
8004 argument unmodified and we assign it to a const_tree. */
8005 type = strip_array_types (CONST_CAST_TREE (type));
8006 if (type == error_mark_node
8007 /* Quals on a FUNCTION_TYPE are memfn quals. */
8008 || TREE_CODE (type) == FUNCTION_TYPE)
8009 return TYPE_UNQUALIFIED;
8010 quals = TYPE_QUALS (type);
8011 /* METHOD and REFERENCE_TYPEs should never have quals. */
8012 gcc_assert ((TREE_CODE (type) != METHOD_TYPE
8013 && TREE_CODE (type) != REFERENCE_TYPE)
8014 || ((quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE))
8015 == TYPE_UNQUALIFIED));
8019 /* Returns the function-cv-quals for TYPE, which must be a FUNCTION_TYPE or
8023 type_memfn_quals (const_tree type)
8025 if (TREE_CODE (type) == FUNCTION_TYPE)
8026 return TYPE_QUALS (type);
8027 else if (TREE_CODE (type) == METHOD_TYPE)
8028 return cp_type_quals (TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (type))));
8033 /* Returns the FUNCTION_TYPE TYPE with its function-cv-quals changed to
8037 apply_memfn_quals (tree type, cp_cv_quals memfn_quals)
8039 /* Could handle METHOD_TYPE here if necessary. */
8040 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
8041 if (TYPE_QUALS (type) == memfn_quals)
8043 /* This should really have a different TYPE_MAIN_VARIANT, but that gets
8045 return build_qualified_type (type, memfn_quals);
8048 /* Returns nonzero if TYPE is const or volatile. */
8051 cv_qualified_p (const_tree type)
8053 int quals = cp_type_quals (type);
8054 return (quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE)) != 0;
8057 /* Returns nonzero if the TYPE contains a mutable member. */
8060 cp_has_mutable_p (const_tree type)
8062 /* This CONST_CAST is okay because strip_array_types returns its
8063 argument unmodified and we assign it to a const_tree. */
8064 type = strip_array_types (CONST_CAST_TREE(type));
8066 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
8069 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
8070 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
8071 approximation. In particular, consider:
8074 struct S { int i; };
8075 const S s = { f(); }
8077 Here, we will make "s" as TREE_READONLY (because it is declared
8078 "const") -- only to reverse ourselves upon seeing that the
8079 initializer is non-constant. */
8082 cp_apply_type_quals_to_decl (int type_quals, tree decl)
8084 tree type = TREE_TYPE (decl);
8086 if (type == error_mark_node)
8089 if (TREE_CODE (decl) == TYPE_DECL)
8092 gcc_assert (!(TREE_CODE (type) == FUNCTION_TYPE
8093 && type_quals != TYPE_UNQUALIFIED));
8095 /* Avoid setting TREE_READONLY incorrectly. */
8096 if (/* If the object has a constructor, the constructor may modify
8098 TYPE_NEEDS_CONSTRUCTING (type)
8099 /* If the type isn't complete, we don't know yet if it will need
8101 || !COMPLETE_TYPE_P (type)
8102 /* If the type has a mutable component, that component might be
8104 || TYPE_HAS_MUTABLE_P (type))
8105 type_quals &= ~TYPE_QUAL_CONST;
8107 c_apply_type_quals_to_decl (type_quals, decl);
8110 /* Subroutine of casts_away_constness. Make T1 and T2 point at
8111 exemplar types such that casting T1 to T2 is casting away constness
8112 if and only if there is no implicit conversion from T1 to T2. */
8115 casts_away_constness_r (tree *t1, tree *t2)
8120 /* [expr.const.cast]
8122 For multi-level pointer to members and multi-level mixed pointers
8123 and pointers to members (conv.qual), the "member" aspect of a
8124 pointer to member level is ignored when determining if a const
8125 cv-qualifier has been cast away. */
8126 /* [expr.const.cast]
8128 For two pointer types:
8130 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
8131 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
8134 casting from X1 to X2 casts away constness if, for a non-pointer
8135 type T there does not exist an implicit conversion (clause
8138 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
8142 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
8143 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
8144 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
8146 *t1 = cp_build_qualified_type (void_type_node,
8147 cp_type_quals (*t1));
8148 *t2 = cp_build_qualified_type (void_type_node,
8149 cp_type_quals (*t2));
8153 quals1 = cp_type_quals (*t1);
8154 quals2 = cp_type_quals (*t2);
8156 if (TYPE_PTRMEM_P (*t1))
8157 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
8159 *t1 = TREE_TYPE (*t1);
8160 if (TYPE_PTRMEM_P (*t2))
8161 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
8163 *t2 = TREE_TYPE (*t2);
8165 casts_away_constness_r (t1, t2);
8166 *t1 = build_pointer_type (*t1);
8167 *t2 = build_pointer_type (*t2);
8168 *t1 = cp_build_qualified_type (*t1, quals1);
8169 *t2 = cp_build_qualified_type (*t2, quals2);
8172 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
8175 ??? This function returns non-zero if casting away qualifiers not
8176 just const. We would like to return to the caller exactly which
8177 qualifiers are casted away to give more accurate diagnostics.
8181 casts_away_constness (tree t1, tree t2)
8183 if (TREE_CODE (t2) == REFERENCE_TYPE)
8185 /* [expr.const.cast]
8187 Casting from an lvalue of type T1 to an lvalue of type T2
8188 using a reference cast casts away constness if a cast from an
8189 rvalue of type "pointer to T1" to the type "pointer to T2"
8190 casts away constness. */
8191 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
8192 return casts_away_constness (build_pointer_type (t1),
8193 build_pointer_type (TREE_TYPE (t2)));
8196 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
8197 /* [expr.const.cast]
8199 Casting from an rvalue of type "pointer to data member of X
8200 of type T1" to the type "pointer to data member of Y of type
8201 T2" casts away constness if a cast from an rvalue of type
8202 "pointer to T1" to the type "pointer to T2" casts away
8204 return casts_away_constness
8205 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
8206 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
8208 /* Casting away constness is only something that makes sense for
8209 pointer or reference types. */
8210 if (TREE_CODE (t1) != POINTER_TYPE
8211 || TREE_CODE (t2) != POINTER_TYPE)
8214 /* Top-level qualifiers don't matter. */
8215 t1 = TYPE_MAIN_VARIANT (t1);
8216 t2 = TYPE_MAIN_VARIANT (t2);
8217 casts_away_constness_r (&t1, &t2);
8218 if (!can_convert (t2, t1))
8224 /* If T is a REFERENCE_TYPE return the type to which T refers.
8225 Otherwise, return T itself. */
8228 non_reference (tree t)
8230 if (TREE_CODE (t) == REFERENCE_TYPE)
8236 /* Return nonzero if REF is an lvalue valid for this language;
8237 otherwise, print an error message and return zero. USE says
8238 how the lvalue is being used and so selects the error message. */
8241 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
8243 int win = lvalue_p (ref);
8245 if (!win && (complain & tf_error))