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, 2010, 2011
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"
37 #include "diagnostic.h"
41 #include "c-family/c-common.h"
42 #include "c-family/c-objc.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, tsubst_flags_t);
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 error_mark_node if the VALUE does not have
68 complete type when this function returns. */
71 require_complete_type_sfinae (tree value, tsubst_flags_t complain)
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_maybe_complain (type, value, complain))
93 return error_mark_node;
97 require_complete_type (tree value)
99 return require_complete_type_sfinae (value, tf_warning_or_error);
102 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
103 a template instantiation, do the instantiation. Returns TYPE,
104 whether or not it could be completed, unless something goes
105 horribly wrong, in which case the error_mark_node is returned. */
108 complete_type (tree type)
110 if (type == NULL_TREE)
111 /* Rather than crash, we return something sure to cause an error
113 return error_mark_node;
115 if (type == error_mark_node || COMPLETE_TYPE_P (type))
117 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
119 tree t = complete_type (TREE_TYPE (type));
120 unsigned int needs_constructing, has_nontrivial_dtor;
121 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
124 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
126 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
127 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
129 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
130 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
133 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
134 instantiate_class_template (TYPE_MAIN_VARIANT (type));
139 /* Like complete_type, but issue an error if the TYPE cannot be completed.
140 VALUE is used for informative diagnostics.
141 Returns NULL_TREE if the type cannot be made complete. */
144 complete_type_or_maybe_complain (tree type, tree value, tsubst_flags_t complain)
146 type = complete_type (type);
147 if (type == error_mark_node)
148 /* We already issued an error. */
150 else if (!COMPLETE_TYPE_P (type))
152 if (complain & tf_error)
153 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
161 complete_type_or_else (tree type, tree value)
163 return complete_type_or_maybe_complain (type, value, tf_warning_or_error);
166 /* Return truthvalue of whether type of EXP is instantiated. */
169 type_unknown_p (const_tree exp)
171 return (TREE_CODE (exp) == TREE_LIST
172 || TREE_TYPE (exp) == unknown_type_node);
176 /* Return the common type of two parameter lists.
177 We assume that comptypes has already been done and returned 1;
178 if that isn't so, this may crash.
180 As an optimization, free the space we allocate if the parameter
181 lists are already common. */
184 commonparms (tree p1, tree p2)
186 tree oldargs = p1, newargs, n;
190 len = list_length (p1);
191 newargs = tree_last (p1);
193 if (newargs == void_list_node)
202 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
207 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
209 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
211 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
214 else if (! TREE_PURPOSE (p1))
216 if (TREE_PURPOSE (p2))
218 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
224 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
226 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
228 if (TREE_VALUE (p1) != TREE_VALUE (p2))
231 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
234 TREE_VALUE (n) = TREE_VALUE (p1);
242 /* Given a type, perhaps copied for a typedef,
243 find the "original" version of it. */
245 original_type (tree t)
247 int quals = cp_type_quals (t);
248 while (t != error_mark_node
249 && TYPE_NAME (t) != NULL_TREE)
251 tree x = TYPE_NAME (t);
252 if (TREE_CODE (x) != TYPE_DECL)
254 x = DECL_ORIGINAL_TYPE (x);
259 return cp_build_qualified_type (t, quals);
262 /* Return the common type for two arithmetic types T1 and T2 under the
263 usual arithmetic conversions. The default conversions have already
264 been applied, and enumerated types converted to their compatible
268 cp_common_type (tree t1, tree t2)
270 enum tree_code code1 = TREE_CODE (t1);
271 enum tree_code code2 = TREE_CODE (t2);
275 /* In what follows, we slightly generalize the rules given in [expr] so
276 as to deal with `long long' and `complex'. First, merge the
278 attributes = (*targetm.merge_type_attributes) (t1, t2);
280 if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2))
282 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
283 return build_type_attribute_variant (t1, attributes);
288 /* FIXME: Attributes. */
289 gcc_assert (ARITHMETIC_TYPE_P (t1)
290 || TREE_CODE (t1) == VECTOR_TYPE
291 || UNSCOPED_ENUM_P (t1));
292 gcc_assert (ARITHMETIC_TYPE_P (t2)
293 || TREE_CODE (t2) == VECTOR_TYPE
294 || UNSCOPED_ENUM_P (t2));
296 /* If one type is complex, form the common type of the non-complex
297 components, then make that complex. Use T1 or T2 if it is the
299 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
301 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
302 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
304 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
306 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
307 return build_type_attribute_variant (t1, attributes);
308 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
309 return build_type_attribute_variant (t2, attributes);
311 return build_type_attribute_variant (build_complex_type (subtype),
315 if (code1 == VECTOR_TYPE)
317 /* When we get here we should have two vectors of the same size.
318 Just prefer the unsigned one if present. */
319 if (TYPE_UNSIGNED (t1))
320 return build_type_attribute_variant (t1, attributes);
322 return build_type_attribute_variant (t2, attributes);
325 /* If only one is real, use it as the result. */
326 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
327 return build_type_attribute_variant (t1, attributes);
328 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
329 return build_type_attribute_variant (t2, attributes);
331 /* Both real or both integers; use the one with greater precision. */
332 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
333 return build_type_attribute_variant (t1, attributes);
334 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
335 return build_type_attribute_variant (t2, attributes);
337 /* The types are the same; no need to do anything fancy. */
338 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
339 return build_type_attribute_variant (t1, attributes);
341 if (code1 != REAL_TYPE)
343 /* If one is unsigned long long, then convert the other to unsigned
345 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
346 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
347 return build_type_attribute_variant (long_long_unsigned_type_node,
349 /* If one is a long long, and the other is an unsigned long, and
350 long long can represent all the values of an unsigned long, then
351 convert to a long long. Otherwise, convert to an unsigned long
352 long. Otherwise, if either operand is long long, convert the
355 Since we're here, we know the TYPE_PRECISION is the same;
356 therefore converting to long long cannot represent all the values
357 of an unsigned long, so we choose unsigned long long in that
359 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
360 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
362 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
363 ? long_long_unsigned_type_node
364 : long_long_integer_type_node);
365 return build_type_attribute_variant (t, attributes);
367 if (int128_integer_type_node != NULL_TREE
368 && (same_type_p (TYPE_MAIN_VARIANT (t1),
369 int128_integer_type_node)
370 || same_type_p (TYPE_MAIN_VARIANT (t2),
371 int128_integer_type_node)))
373 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
374 ? int128_unsigned_type_node
375 : int128_integer_type_node);
376 return build_type_attribute_variant (t, attributes);
379 /* Go through the same procedure, but for longs. */
380 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
381 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
382 return build_type_attribute_variant (long_unsigned_type_node,
384 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
387 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
388 ? long_unsigned_type_node : long_integer_type_node);
389 return build_type_attribute_variant (t, attributes);
391 /* Otherwise prefer the unsigned one. */
392 if (TYPE_UNSIGNED (t1))
393 return build_type_attribute_variant (t1, attributes);
395 return build_type_attribute_variant (t2, attributes);
399 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
400 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
401 return build_type_attribute_variant (long_double_type_node,
403 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
404 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
405 return build_type_attribute_variant (double_type_node,
407 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
408 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
409 return build_type_attribute_variant (float_type_node,
412 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
413 the standard C++ floating-point types. Logic earlier in this
414 function has already eliminated the possibility that
415 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
416 compelling reason to choose one or the other. */
417 return build_type_attribute_variant (t1, attributes);
421 /* T1 and T2 are arithmetic or enumeration types. Return the type
422 that will result from the "usual arithmetic conversions" on T1 and
423 T2 as described in [expr]. */
426 type_after_usual_arithmetic_conversions (tree t1, tree t2)
428 gcc_assert (ARITHMETIC_TYPE_P (t1)
429 || TREE_CODE (t1) == VECTOR_TYPE
430 || UNSCOPED_ENUM_P (t1));
431 gcc_assert (ARITHMETIC_TYPE_P (t2)
432 || TREE_CODE (t2) == VECTOR_TYPE
433 || UNSCOPED_ENUM_P (t2));
435 /* Perform the integral promotions. We do not promote real types here. */
436 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
437 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
439 t1 = type_promotes_to (t1);
440 t2 = type_promotes_to (t2);
443 return cp_common_type (t1, t2);
447 composite_pointer_error (diagnostic_t kind, tree t1, tree t2,
448 composite_pointer_operation operation)
453 emit_diagnostic (kind, input_location, 0,
454 "comparison between "
455 "distinct pointer types %qT and %qT lacks a cast",
459 emit_diagnostic (kind, input_location, 0,
460 "conversion between "
461 "distinct pointer types %qT and %qT lacks a cast",
464 case CPO_CONDITIONAL_EXPR:
465 emit_diagnostic (kind, input_location, 0,
466 "conditional expression between "
467 "distinct pointer types %qT and %qT lacks a cast",
475 /* Subroutine of composite_pointer_type to implement the recursive
476 case. See that function for documentation of the parameters. */
479 composite_pointer_type_r (tree t1, tree t2,
480 composite_pointer_operation operation,
481 tsubst_flags_t complain)
488 /* Determine the types pointed to by T1 and T2. */
489 if (TREE_CODE (t1) == POINTER_TYPE)
491 pointee1 = TREE_TYPE (t1);
492 pointee2 = TREE_TYPE (t2);
496 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
497 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
502 Otherwise, the composite pointer type is a pointer type
503 similar (_conv.qual_) to the type of one of the operands,
504 with a cv-qualification signature (_conv.qual_) that is the
505 union of the cv-qualification signatures of the operand
507 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
508 result_type = pointee1;
509 else if ((TREE_CODE (pointee1) == POINTER_TYPE
510 && TREE_CODE (pointee2) == POINTER_TYPE)
511 || (TYPE_PTR_TO_MEMBER_P (pointee1)
512 && TYPE_PTR_TO_MEMBER_P (pointee2)))
514 result_type = composite_pointer_type_r (pointee1, pointee2, operation,
516 if (result_type == error_mark_node)
517 return error_mark_node;
521 if (complain & tf_error)
522 composite_pointer_error (DK_PERMERROR, t1, t2, operation);
524 return error_mark_node;
525 result_type = void_type_node;
527 result_type = cp_build_qualified_type (result_type,
528 (cp_type_quals (pointee1)
529 | cp_type_quals (pointee2)));
530 /* If the original types were pointers to members, so is the
532 if (TYPE_PTR_TO_MEMBER_P (t1))
534 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
535 TYPE_PTRMEM_CLASS_TYPE (t2)))
537 if (complain & tf_error)
538 composite_pointer_error (DK_PERMERROR, t1, t2, operation);
540 return error_mark_node;
542 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
546 result_type = build_pointer_type (result_type);
548 /* Merge the attributes. */
549 attributes = (*targetm.merge_type_attributes) (t1, t2);
550 return build_type_attribute_variant (result_type, attributes);
553 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
554 ARG1 and ARG2 are the values with those types. The OPERATION is to
555 describe the operation between the pointer types,
556 in case an error occurs.
558 This routine also implements the computation of a common type for
559 pointers-to-members as per [expr.eq]. */
562 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
563 composite_pointer_operation operation,
564 tsubst_flags_t complain)
571 If one operand is a null pointer constant, the composite pointer
572 type is the type of the other operand. */
573 if (null_ptr_cst_p (arg1))
575 if (null_ptr_cst_p (arg2))
582 If one of the operands has type "pointer to cv1 void*", then
583 the other has type "pointer to cv2T", and the composite pointer
584 type is "pointer to cv12 void", where cv12 is the union of cv1
587 If either type is a pointer to void, make sure it is T1. */
588 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
596 /* Now, if T1 is a pointer to void, merge the qualifiers. */
597 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
602 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
607 pedwarn (input_location, OPT_pedantic,
608 "ISO C++ forbids comparison between "
609 "pointer of type %<void *%> and pointer-to-function");
612 pedwarn (input_location, OPT_pedantic,
613 "ISO C++ forbids conversion between "
614 "pointer of type %<void *%> and pointer-to-function");
616 case CPO_CONDITIONAL_EXPR:
617 pedwarn (input_location, OPT_pedantic,
618 "ISO C++ forbids conditional expression between "
619 "pointer of type %<void *%> and pointer-to-function");
626 = cp_build_qualified_type (void_type_node,
627 (cp_type_quals (TREE_TYPE (t1))
628 | cp_type_quals (TREE_TYPE (t2))));
629 result_type = build_pointer_type (result_type);
630 /* Merge the attributes. */
631 attributes = (*targetm.merge_type_attributes) (t1, t2);
632 return build_type_attribute_variant (result_type, attributes);
635 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
636 && TREE_CODE (t2) == POINTER_TYPE)
638 if (objc_have_common_type (t1, t2, -3, NULL_TREE))
639 return objc_common_type (t1, t2);
642 /* [expr.eq] permits the application of a pointer conversion to
643 bring the pointers to a common type. */
644 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
645 && CLASS_TYPE_P (TREE_TYPE (t1))
646 && CLASS_TYPE_P (TREE_TYPE (t2))
647 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
650 class1 = TREE_TYPE (t1);
651 class2 = TREE_TYPE (t2);
653 if (DERIVED_FROM_P (class1, class2))
654 t2 = (build_pointer_type
655 (cp_build_qualified_type (class1, cp_type_quals (class2))));
656 else if (DERIVED_FROM_P (class2, class1))
657 t1 = (build_pointer_type
658 (cp_build_qualified_type (class2, cp_type_quals (class1))));
661 if (complain & tf_error)
662 composite_pointer_error (DK_ERROR, t1, t2, operation);
663 return error_mark_node;
666 /* [expr.eq] permits the application of a pointer-to-member
667 conversion to change the class type of one of the types. */
668 else if (TYPE_PTR_TO_MEMBER_P (t1)
669 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
670 TYPE_PTRMEM_CLASS_TYPE (t2)))
672 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
673 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
675 if (DERIVED_FROM_P (class1, class2))
676 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
677 else if (DERIVED_FROM_P (class2, class1))
678 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
681 if (complain & tf_error)
685 error ("comparison between distinct "
686 "pointer-to-member types %qT and %qT lacks a cast",
690 error ("conversion between distinct "
691 "pointer-to-member types %qT and %qT lacks a cast",
694 case CPO_CONDITIONAL_EXPR:
695 error ("conditional expression between distinct "
696 "pointer-to-member types %qT and %qT lacks a cast",
702 return error_mark_node;
706 return composite_pointer_type_r (t1, t2, operation, complain);
709 /* Return the merged type of two types.
710 We assume that comptypes has already been done and returned 1;
711 if that isn't so, this may crash.
713 This just combines attributes and default arguments; any other
714 differences would cause the two types to compare unalike. */
717 merge_types (tree t1, tree t2)
719 enum tree_code code1;
720 enum tree_code code2;
723 /* Save time if the two types are the same. */
726 if (original_type (t1) == original_type (t2))
729 /* If one type is nonsense, use the other. */
730 if (t1 == error_mark_node)
732 if (t2 == error_mark_node)
735 /* Merge the attributes. */
736 attributes = (*targetm.merge_type_attributes) (t1, t2);
738 if (TYPE_PTRMEMFUNC_P (t1))
739 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
740 if (TYPE_PTRMEMFUNC_P (t2))
741 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
743 code1 = TREE_CODE (t1);
744 code2 = TREE_CODE (t2);
747 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
748 if (code1 == TYPENAME_TYPE)
750 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
751 code1 = TREE_CODE (t1);
755 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
756 code2 = TREE_CODE (t2);
764 /* For two pointers, do this recursively on the target type. */
766 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
767 int quals = cp_type_quals (t1);
769 if (code1 == POINTER_TYPE)
770 t1 = build_pointer_type (target);
772 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
773 t1 = build_type_attribute_variant (t1, attributes);
774 t1 = cp_build_qualified_type (t1, quals);
776 if (TREE_CODE (target) == METHOD_TYPE)
777 t1 = build_ptrmemfunc_type (t1);
786 quals = cp_type_quals (t1);
787 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
788 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
789 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
791 t1 = cp_build_qualified_type (t1, quals);
797 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
798 /* Save space: see if the result is identical to one of the args. */
799 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
800 return build_type_attribute_variant (t1, attributes);
801 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
802 return build_type_attribute_variant (t2, attributes);
803 /* Merge the element types, and have a size if either arg has one. */
804 t1 = build_cplus_array_type
805 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
810 /* Function types: prefer the one that specified arg types.
811 If both do, merge the arg types. Also merge the return types. */
813 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
814 tree p1 = TYPE_ARG_TYPES (t1);
815 tree p2 = TYPE_ARG_TYPES (t2);
819 /* Save space: see if the result is identical to one of the args. */
820 if (valtype == TREE_TYPE (t1) && ! p2)
821 return cp_build_type_attribute_variant (t1, attributes);
822 if (valtype == TREE_TYPE (t2) && ! p1)
823 return cp_build_type_attribute_variant (t2, attributes);
825 /* Simple way if one arg fails to specify argument types. */
826 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
828 else if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
831 parms = commonparms (p1, p2);
833 rval = build_function_type (valtype, parms);
834 gcc_assert (type_memfn_quals (t1) == type_memfn_quals (t2));
835 rval = apply_memfn_quals (rval, type_memfn_quals (t1));
836 raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
837 TYPE_RAISES_EXCEPTIONS (t2),
839 t1 = build_exception_variant (rval, raises);
845 /* Get this value the long way, since TYPE_METHOD_BASETYPE
846 is just the main variant of this. */
847 tree basetype = class_of_this_parm (t2);
848 tree raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
849 TYPE_RAISES_EXCEPTIONS (t2),
853 /* If this was a member function type, get back to the
854 original type of type member function (i.e., without
855 the class instance variable up front. */
856 t1 = build_function_type (TREE_TYPE (t1),
857 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
858 t2 = build_function_type (TREE_TYPE (t2),
859 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
860 t3 = merge_types (t1, t2);
861 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
862 TYPE_ARG_TYPES (t3));
863 t1 = build_exception_variant (t3, raises);
868 /* There is no need to merge attributes into a TYPENAME_TYPE.
869 When the type is instantiated it will have whatever
870 attributes result from the instantiation. */
876 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
878 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
881 return cp_build_type_attribute_variant (t1, attributes);
884 /* Return the ARRAY_TYPE type without its domain. */
887 strip_array_domain (tree type)
890 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
891 if (TYPE_DOMAIN (type) == NULL_TREE)
893 t2 = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
894 return cp_build_type_attribute_variant (t2, TYPE_ATTRIBUTES (type));
897 /* Wrapper around cp_common_type that is used by c-common.c and other
898 front end optimizations that remove promotions.
900 Return the common type for two arithmetic types T1 and T2 under the
901 usual arithmetic conversions. The default conversions have already
902 been applied, and enumerated types converted to their compatible
906 common_type (tree t1, tree t2)
908 /* If one type is nonsense, use the other */
909 if (t1 == error_mark_node)
911 if (t2 == error_mark_node)
914 return cp_common_type (t1, t2);
917 /* Return the common type of two pointer types T1 and T2. This is the
918 type for the result of most arithmetic operations if the operands
919 have the given two types.
921 We assume that comp_target_types has already been done and returned
922 nonzero; if that isn't so, this may crash. */
925 common_pointer_type (tree t1, tree t2)
927 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
928 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
929 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
931 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
932 CPO_CONVERSION, tf_warning_or_error);
935 /* Compare two exception specifier types for exactness or subsetness, if
936 allowed. Returns false for mismatch, true for match (same, or
939 [except.spec] "If a class X ... objects of class X or any class publicly
940 and unambiguously derived from X. Similarly, if a pointer type Y * ...
941 exceptions of type Y * or that are pointers to any type publicly and
942 unambiguously derived from Y. Otherwise a function only allows exceptions
943 that have the same type ..."
944 This does not mention cv qualifiers and is different to what throw
945 [except.throw] and catch [except.catch] will do. They will ignore the
946 top level cv qualifiers, and allow qualifiers in the pointer to class
949 We implement the letter of the standard. */
952 comp_except_types (tree a, tree b, bool exact)
954 if (same_type_p (a, b))
958 if (cp_type_quals (a) || cp_type_quals (b))
961 if (TREE_CODE (a) == POINTER_TYPE
962 && TREE_CODE (b) == POINTER_TYPE)
966 if (cp_type_quals (a) || cp_type_quals (b))
970 if (TREE_CODE (a) != RECORD_TYPE
971 || TREE_CODE (b) != RECORD_TYPE)
974 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
980 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
981 If EXACT is ce_derived, T2 can be stricter than T1 (according to 15.4/5).
982 If EXACT is ce_normal, the compatibility rules in 15.4/3 apply.
983 If EXACT is ce_exact, the specs must be exactly the same. Exception lists
984 are unordered, but we've already filtered out duplicates. Most lists will
985 be in order, we should try to make use of that. */
988 comp_except_specs (const_tree t1, const_tree t2, int exact)
997 /* First handle noexcept. */
998 if (exact < ce_exact)
1000 /* noexcept(false) is compatible with no exception-specification,
1001 and stricter than any spec. */
1002 if (t1 == noexcept_false_spec)
1003 return t2 == NULL_TREE || exact == ce_derived;
1004 /* Even a derived noexcept(false) is compatible with no
1005 exception-specification. */
1006 if (t2 == noexcept_false_spec)
1007 return t1 == NULL_TREE;
1009 /* Otherwise, if we aren't looking for an exact match, noexcept is
1010 equivalent to throw(). */
1011 if (t1 == noexcept_true_spec)
1012 t1 = empty_except_spec;
1013 if (t2 == noexcept_true_spec)
1014 t2 = empty_except_spec;
1017 /* If any noexcept is left, it is only comparable to itself;
1018 either we're looking for an exact match or we're redeclaring a
1019 template with dependent noexcept. */
1020 if ((t1 && TREE_PURPOSE (t1))
1021 || (t2 && TREE_PURPOSE (t2)))
1023 && cp_tree_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2)));
1025 if (t1 == NULL_TREE) /* T1 is ... */
1026 return t2 == NULL_TREE || exact == ce_derived;
1027 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
1028 return t2 != NULL_TREE && !TREE_VALUE (t2);
1029 if (t2 == NULL_TREE) /* T2 is ... */
1031 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
1032 return exact == ce_derived;
1034 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
1035 Count how many we find, to determine exactness. For exact matching and
1036 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
1038 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
1040 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
1042 tree a = TREE_VALUE (probe);
1043 tree b = TREE_VALUE (t2);
1045 if (comp_except_types (a, b, exact))
1047 if (probe == base && exact > ce_derived)
1048 base = TREE_CHAIN (probe);
1053 if (probe == NULL_TREE)
1056 return exact == ce_derived || base == NULL_TREE || length == list_length (t1);
1059 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
1060 [] can match [size]. */
1063 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
1072 /* The type of the array elements must be the same. */
1073 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1076 d1 = TYPE_DOMAIN (t1);
1077 d2 = TYPE_DOMAIN (t2);
1082 /* If one of the arrays is dimensionless, and the other has a
1083 dimension, they are of different types. However, it is valid to
1091 declarations for an array object can specify
1092 array types that differ by the presence or absence of a major
1093 array bound (_dcl.array_). */
1095 return allow_redeclaration;
1097 /* Check that the dimensions are the same. */
1099 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
1101 max1 = TYPE_MAX_VALUE (d1);
1102 max2 = TYPE_MAX_VALUE (d2);
1103 if (processing_template_decl && !abi_version_at_least (2)
1104 && !value_dependent_expression_p (max1)
1105 && !value_dependent_expression_p (max2))
1107 /* With abi-1 we do not fold non-dependent array bounds, (and
1108 consequently mangle them incorrectly). We must therefore
1109 fold them here, to verify the domains have the same
1115 if (!cp_tree_equal (max1, max2))
1121 /* Compare the relative position of T1 and T2 into their respective
1122 template parameter list.
1123 T1 and T2 must be template parameter types.
1124 Return TRUE if T1 and T2 have the same position, FALSE otherwise. */
1127 comp_template_parms_position (tree t1, tree t2)
1129 tree index1, index2;
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 index1 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t1));
1137 index2 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t2));
1139 /* If T1 and T2 belong to template parm lists of different size,
1140 let's assume they are different. */
1141 if (TEMPLATE_PARM_NUM_SIBLINGS (index1)
1142 != TEMPLATE_PARM_NUM_SIBLINGS (index2))
1145 /* Then compare their relative position. */
1146 if (TEMPLATE_PARM_IDX (index1) != TEMPLATE_PARM_IDX (index2)
1147 || TEMPLATE_PARM_LEVEL (index1) != TEMPLATE_PARM_LEVEL (index2)
1148 || (TEMPLATE_PARM_PARAMETER_PACK (index1)
1149 != TEMPLATE_PARM_PARAMETER_PACK (index2)))
1155 /* Subroutine in comptypes. */
1158 structural_comptypes (tree t1, tree t2, int strict)
1163 /* Suppress errors caused by previously reported errors. */
1164 if (t1 == error_mark_node || t2 == error_mark_node)
1167 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
1169 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
1170 current instantiation. */
1171 if (TREE_CODE (t1) == TYPENAME_TYPE)
1172 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1174 if (TREE_CODE (t2) == TYPENAME_TYPE)
1175 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1177 if (TYPE_PTRMEMFUNC_P (t1))
1178 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1179 if (TYPE_PTRMEMFUNC_P (t2))
1180 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1182 /* Different classes of types can't be compatible. */
1183 if (TREE_CODE (t1) != TREE_CODE (t2))
1186 /* Qualifiers must match. For array types, we will check when we
1187 recur on the array element types. */
1188 if (TREE_CODE (t1) != ARRAY_TYPE
1189 && cp_type_quals (t1) != cp_type_quals (t2))
1191 if (TREE_CODE (t1) == FUNCTION_TYPE
1192 && type_memfn_quals (t1) != type_memfn_quals (t2))
1194 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1197 /* Allow for two different type nodes which have essentially the same
1198 definition. Note that we already checked for equality of the type
1199 qualifiers (just above). */
1201 if (TREE_CODE (t1) != ARRAY_TYPE
1202 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1206 /* Compare the types. Break out if they could be the same. */
1207 switch (TREE_CODE (t1))
1211 /* All void and bool types are the same. */
1215 case FIXED_POINT_TYPE:
1217 /* With these nodes, we can't determine type equivalence by
1218 looking at what is stored in the nodes themselves, because
1219 two nodes might have different TYPE_MAIN_VARIANTs but still
1220 represent the same type. For example, wchar_t and int could
1221 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1222 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1223 and are distinct types. On the other hand, int and the
1226 typedef int INT __attribute((may_alias));
1228 have identical properties, different TYPE_MAIN_VARIANTs, but
1229 represent the same type. The canonical type system keeps
1230 track of equivalence in this case, so we fall back on it. */
1231 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1233 case TEMPLATE_TEMPLATE_PARM:
1234 case BOUND_TEMPLATE_TEMPLATE_PARM:
1235 if (!comp_template_parms_position (t1, t2))
1237 if (!comp_template_parms
1238 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1239 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1241 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1243 /* Don't check inheritance. */
1244 strict = COMPARE_STRICT;
1249 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1250 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1251 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1252 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1255 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1257 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1263 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1264 strict & ~COMPARE_REDECLARATION))
1266 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1270 case REFERENCE_TYPE:
1271 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1273 /* fall through to checks for pointer types */
1276 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1277 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1278 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1284 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1286 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1291 /* Target types must match incl. qualifiers. */
1292 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1296 case TEMPLATE_TYPE_PARM:
1297 /* If T1 and T2 don't have the same relative position in their
1298 template parameters set, they can't be equal. */
1299 if (!comp_template_parms_position (t1, t2))
1304 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1305 TYPENAME_TYPE_FULLNAME (t2)))
1307 /* Qualifiers don't matter on scopes. */
1308 if (!same_type_ignoring_top_level_qualifiers_p (TYPE_CONTEXT (t1),
1313 case UNBOUND_CLASS_TEMPLATE:
1314 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1316 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1321 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1326 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1327 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1331 case TYPE_PACK_EXPANSION:
1332 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1333 PACK_EXPANSION_PATTERN (t2));
1336 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1337 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1338 || (DECLTYPE_FOR_LAMBDA_CAPTURE (t1)
1339 != DECLTYPE_FOR_LAMBDA_CAPTURE (t2))
1340 || (DECLTYPE_FOR_LAMBDA_PROXY (t1)
1341 != DECLTYPE_FOR_LAMBDA_PROXY (t2))
1342 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1343 DECLTYPE_TYPE_EXPR (t2)))
1347 case UNDERLYING_TYPE:
1348 return same_type_p (UNDERLYING_TYPE_TYPE (t1),
1349 UNDERLYING_TYPE_TYPE (t2));
1355 /* If we get here, we know that from a target independent POV the
1356 types are the same. Make sure the target attributes are also
1358 return comp_type_attributes (t1, t2);
1361 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1362 is a bitwise-or of the COMPARE_* flags. */
1365 comptypes (tree t1, tree t2, int strict)
1367 if (strict == COMPARE_STRICT)
1372 if (t1 == error_mark_node || t2 == error_mark_node)
1375 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1376 /* At least one of the types requires structural equality, so
1377 perform a deep check. */
1378 return structural_comptypes (t1, t2, strict);
1380 #ifdef ENABLE_CHECKING
1381 if (USE_CANONICAL_TYPES)
1383 bool result = structural_comptypes (t1, t2, strict);
1385 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1386 /* The two types are structurally equivalent, but their
1387 canonical types were different. This is a failure of the
1388 canonical type propagation code.*/
1390 ("canonical types differ for identical types %T and %T",
1392 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1393 /* Two types are structurally different, but the canonical
1394 types are the same. This means we were over-eager in
1395 assigning canonical types. */
1397 ("same canonical type node for different types %T and %T",
1403 if (USE_CANONICAL_TYPES)
1404 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1407 return structural_comptypes (t1, t2, strict);
1409 else if (strict == COMPARE_STRUCTURAL)
1410 return structural_comptypes (t1, t2, COMPARE_STRICT);
1412 return structural_comptypes (t1, t2, strict);
1415 /* Returns nonzero iff TYPE1 and TYPE2 are the same type, ignoring
1416 top-level qualifiers. */
1419 same_type_ignoring_top_level_qualifiers_p (tree type1, tree type2)
1421 if (type1 == error_mark_node || type2 == error_mark_node)
1424 return same_type_p (TYPE_MAIN_VARIANT (type1), TYPE_MAIN_VARIANT (type2));
1427 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1430 at_least_as_qualified_p (const_tree type1, const_tree type2)
1432 int q1 = cp_type_quals (type1);
1433 int q2 = cp_type_quals (type2);
1435 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1436 return (q1 & q2) == q2;
1439 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1440 more cv-qualified that TYPE1, and 0 otherwise. */
1443 comp_cv_qualification (const_tree type1, const_tree type2)
1445 int q1 = cp_type_quals (type1);
1446 int q2 = cp_type_quals (type2);
1451 if ((q1 & q2) == q2)
1453 else if ((q1 & q2) == q1)
1459 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1460 subset of the cv-qualification signature of TYPE2, and the types
1461 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1464 comp_cv_qual_signature (tree type1, tree type2)
1466 if (comp_ptr_ttypes_real (type2, type1, -1))
1468 else if (comp_ptr_ttypes_real (type1, type2, -1))
1474 /* Subroutines of `comptypes'. */
1476 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1477 equivalent in the sense that functions with those parameter types
1478 can have equivalent types. The two lists must be equivalent,
1479 element by element. */
1482 compparms (const_tree parms1, const_tree parms2)
1486 /* An unspecified parmlist matches any specified parmlist
1487 whose argument types don't need default promotions. */
1489 for (t1 = parms1, t2 = parms2;
1491 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1493 /* If one parmlist is shorter than the other,
1494 they fail to match. */
1497 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1504 /* Process a sizeof or alignof expression where the operand is a
1508 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1513 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1514 if (type == error_mark_node)
1515 return error_mark_node;
1517 type = non_reference (type);
1518 if (TREE_CODE (type) == METHOD_TYPE)
1521 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1522 "invalid application of %qs to a member function",
1523 operator_name_info[(int) op].name);
1524 value = size_one_node;
1527 dependent_p = dependent_type_p (type);
1529 complete_type (type);
1531 /* VLA types will have a non-constant size. In the body of an
1532 uninstantiated template, we don't need to try to compute the
1533 value, because the sizeof expression is not an integral
1534 constant expression in that case. And, if we do try to
1535 compute the value, we'll likely end up with SAVE_EXPRs, which
1536 the template substitution machinery does not expect to see. */
1537 || (processing_template_decl
1538 && COMPLETE_TYPE_P (type)
1539 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1541 value = build_min (op, size_type_node, type);
1542 TREE_READONLY (value) = 1;
1546 return c_sizeof_or_alignof_type (input_location, complete_type (type),
1551 /* Return the size of the type, without producing any warnings for
1552 types whose size cannot be taken. This routine should be used only
1553 in some other routine that has already produced a diagnostic about
1554 using the size of such a type. */
1556 cxx_sizeof_nowarn (tree type)
1558 if (TREE_CODE (type) == FUNCTION_TYPE
1559 || TREE_CODE (type) == VOID_TYPE
1560 || TREE_CODE (type) == ERROR_MARK)
1561 return size_one_node;
1562 else if (!COMPLETE_TYPE_P (type))
1563 return size_zero_node;
1565 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1568 /* Process a sizeof expression where the operand is an expression. */
1571 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1573 if (e == error_mark_node)
1574 return error_mark_node;
1576 if (processing_template_decl)
1578 e = build_min (SIZEOF_EXPR, size_type_node, e);
1579 TREE_SIDE_EFFECTS (e) = 0;
1580 TREE_READONLY (e) = 1;
1585 /* To get the size of a static data member declared as an array of
1586 unknown bound, we need to instantiate it. */
1587 if (TREE_CODE (e) == VAR_DECL
1588 && VAR_HAD_UNKNOWN_BOUND (e)
1589 && DECL_TEMPLATE_INSTANTIATION (e))
1590 instantiate_decl (e, /*defer_ok*/true, /*expl_inst_mem*/false);
1592 e = mark_type_use (e);
1594 if (TREE_CODE (e) == COMPONENT_REF
1595 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1596 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1598 if (complain & tf_error)
1599 error ("invalid application of %<sizeof%> to a bit-field");
1601 return error_mark_node;
1604 else if (is_overloaded_fn (e))
1606 if (complain & tf_error)
1607 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1610 return error_mark_node;
1613 else if (type_unknown_p (e))
1615 if (complain & tf_error)
1616 cxx_incomplete_type_error (e, TREE_TYPE (e));
1618 return error_mark_node;
1624 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1627 /* Implement the __alignof keyword: Return the minimum required
1628 alignment of E, measured in bytes. For VAR_DECL's and
1629 FIELD_DECL's return DECL_ALIGN (which can be set from an
1630 "aligned" __attribute__ specification). */
1633 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1637 if (e == error_mark_node)
1638 return error_mark_node;
1640 if (processing_template_decl)
1642 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1643 TREE_SIDE_EFFECTS (e) = 0;
1644 TREE_READONLY (e) = 1;
1649 e = mark_type_use (e);
1651 if (TREE_CODE (e) == VAR_DECL)
1652 t = size_int (DECL_ALIGN_UNIT (e));
1653 else if (TREE_CODE (e) == COMPONENT_REF
1654 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1655 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1657 if (complain & tf_error)
1658 error ("invalid application of %<__alignof%> to a bit-field");
1660 return error_mark_node;
1663 else if (TREE_CODE (e) == COMPONENT_REF
1664 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1665 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1666 else if (is_overloaded_fn (e))
1668 if (complain & tf_error)
1669 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1672 return error_mark_node;
1673 if (TREE_CODE (e) == FUNCTION_DECL)
1674 t = size_int (DECL_ALIGN_UNIT (e));
1678 else if (type_unknown_p (e))
1680 if (complain & tf_error)
1681 cxx_incomplete_type_error (e, TREE_TYPE (e));
1683 return error_mark_node;
1687 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1688 complain & tf_error);
1690 return fold_convert (size_type_node, t);
1693 /* Process a sizeof or alignof expression E with code OP where the operand
1694 is an expression. */
1697 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1699 if (op == SIZEOF_EXPR)
1700 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1702 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1705 /* EXPR is being used in a context that is not a function call.
1710 The expression can be used only as the left-hand operand of a
1711 member function call.
1713 [expr.mptr.operator]
1715 If the result of .* or ->* is a function, then that result can be
1716 used only as the operand for the function call operator ().
1718 by issuing an error message if appropriate. Returns true iff EXPR
1719 violates these rules. */
1722 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1724 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1726 if (complain & tf_error)
1727 error ("invalid use of non-static member function");
1733 /* If EXP is a reference to a bitfield, and the type of EXP does not
1734 match the declared type of the bitfield, return the declared type
1735 of the bitfield. Otherwise, return NULL_TREE. */
1738 is_bitfield_expr_with_lowered_type (const_tree exp)
1740 switch (TREE_CODE (exp))
1743 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1744 ? TREE_OPERAND (exp, 1)
1745 : TREE_OPERAND (exp, 0)))
1747 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1750 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1754 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1760 field = TREE_OPERAND (exp, 1);
1761 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1763 if (same_type_ignoring_top_level_qualifiers_p
1764 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1766 return DECL_BIT_FIELD_TYPE (field);
1770 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1771 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1772 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1780 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1781 bitfield with a lowered type, the type of EXP is returned, rather
1785 unlowered_expr_type (const_tree exp)
1788 tree etype = TREE_TYPE (exp);
1790 type = is_bitfield_expr_with_lowered_type (exp);
1792 type = cp_build_qualified_type (type, cp_type_quals (etype));
1799 /* Perform the conversions in [expr] that apply when an lvalue appears
1800 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1801 function-to-pointer conversions. In addition, manifest constants
1802 are replaced by their values, and bitfield references are converted
1803 to their declared types. Note that this function does not perform the
1804 lvalue-to-rvalue conversion for class types. If you need that conversion
1805 to for class types, then you probably need to use force_rvalue.
1807 Although the returned value is being used as an rvalue, this
1808 function does not wrap the returned expression in a
1809 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1810 that the return value is no longer an lvalue. */
1813 decay_conversion (tree exp)
1816 enum tree_code code;
1818 type = TREE_TYPE (exp);
1819 if (type == error_mark_node)
1820 return error_mark_node;
1822 exp = mark_rvalue_use (exp);
1824 exp = resolve_nondeduced_context (exp);
1825 if (type_unknown_p (exp))
1827 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1828 return error_mark_node;
1831 /* FIXME remove? at least need to remember that this isn't really a
1832 constant expression if EXP isn't decl_constant_var_p, like with
1833 C_MAYBE_CONST_EXPR. */
1834 exp = decl_constant_value_safe (exp);
1835 if (error_operand_p (exp))
1836 return error_mark_node;
1838 if (NULLPTR_TYPE_P (type))
1839 return nullptr_node;
1841 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1842 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1843 code = TREE_CODE (type);
1844 if (code == VOID_TYPE)
1846 error ("void value not ignored as it ought to be");
1847 return error_mark_node;
1849 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1850 return error_mark_node;
1851 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1852 return cp_build_addr_expr (exp, tf_warning_or_error);
1853 if (code == ARRAY_TYPE)
1858 if (TREE_CODE (exp) == INDIRECT_REF)
1859 return build_nop (build_pointer_type (TREE_TYPE (type)),
1860 TREE_OPERAND (exp, 0));
1862 if (TREE_CODE (exp) == COMPOUND_EXPR)
1864 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1865 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1866 TREE_OPERAND (exp, 0), op1);
1870 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1872 error ("invalid use of non-lvalue array");
1873 return error_mark_node;
1876 ptrtype = build_pointer_type (TREE_TYPE (type));
1878 if (TREE_CODE (exp) == VAR_DECL)
1880 if (!cxx_mark_addressable (exp))
1881 return error_mark_node;
1882 adr = build_nop (ptrtype, build_address (exp));
1885 /* This way is better for a COMPONENT_REF since it can
1886 simplify the offset for a component. */
1887 adr = cp_build_addr_expr (exp, tf_warning_or_error);
1888 return cp_convert (ptrtype, adr);
1891 /* If a bitfield is used in a context where integral promotion
1892 applies, then the caller is expected to have used
1893 default_conversion. That function promotes bitfields correctly
1894 before calling this function. At this point, if we have a
1895 bitfield referenced, we may assume that is not subject to
1896 promotion, and that, therefore, the type of the resulting rvalue
1897 is the declared type of the bitfield. */
1898 exp = convert_bitfield_to_declared_type (exp);
1900 /* We do not call rvalue() here because we do not want to wrap EXP
1901 in a NON_LVALUE_EXPR. */
1905 Non-class rvalues always have cv-unqualified types. */
1906 type = TREE_TYPE (exp);
1907 if (!CLASS_TYPE_P (type) && cv_qualified_p (type))
1908 exp = build_nop (cv_unqualified (type), exp);
1913 /* Perform preparatory conversions, as part of the "usual arithmetic
1914 conversions". In particular, as per [expr]:
1916 Whenever an lvalue expression appears as an operand of an
1917 operator that expects the rvalue for that operand, the
1918 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1919 standard conversions are applied to convert the expression to an
1922 In addition, we perform integral promotions here, as those are
1923 applied to both operands to a binary operator before determining
1924 what additional conversions should apply. */
1927 default_conversion (tree exp)
1929 /* Check for target-specific promotions. */
1930 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
1932 exp = cp_convert (promoted_type, exp);
1933 /* Perform the integral promotions first so that bitfield
1934 expressions (which may promote to "int", even if the bitfield is
1935 declared "unsigned") are promoted correctly. */
1936 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1937 exp = perform_integral_promotions (exp);
1938 /* Perform the other conversions. */
1939 exp = decay_conversion (exp);
1944 /* EXPR is an expression with an integral or enumeration type.
1945 Perform the integral promotions in [conv.prom], and return the
1949 perform_integral_promotions (tree expr)
1954 expr = mark_rvalue_use (expr);
1958 If the bitfield has an enumerated type, it is treated as any
1959 other value of that type for promotion purposes. */
1960 type = is_bitfield_expr_with_lowered_type (expr);
1961 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1962 type = TREE_TYPE (expr);
1963 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1964 /* Scoped enums don't promote. */
1965 if (SCOPED_ENUM_P (type))
1967 promoted_type = type_promotes_to (type);
1968 if (type != promoted_type)
1969 expr = cp_convert (promoted_type, expr);
1973 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1974 decay_conversion to one. */
1977 string_conv_p (const_tree totype, const_tree exp, int warn)
1981 if (TREE_CODE (totype) != POINTER_TYPE)
1984 t = TREE_TYPE (totype);
1985 if (!same_type_p (t, char_type_node)
1986 && !same_type_p (t, char16_type_node)
1987 && !same_type_p (t, char32_type_node)
1988 && !same_type_p (t, wchar_type_node))
1991 if (TREE_CODE (exp) == STRING_CST)
1993 /* Make sure that we don't try to convert between char and wide chars. */
1994 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1999 /* Is this a string constant which has decayed to 'const char *'? */
2000 t = build_pointer_type (cp_build_qualified_type (t, TYPE_QUAL_CONST));
2001 if (!same_type_p (TREE_TYPE (exp), t))
2004 if (TREE_CODE (exp) != ADDR_EXPR
2005 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
2009 /* This warning is not very useful, as it complains about printf. */
2011 warning (OPT_Wwrite_strings,
2012 "deprecated conversion from string constant to %qT",
2018 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
2019 can, for example, use as an lvalue. This code used to be in
2020 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
2021 expressions, where we're dealing with aggregates. But now it's again only
2022 called from unary_complex_lvalue. The case (in particular) that led to
2023 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
2027 rationalize_conditional_expr (enum tree_code code, tree t,
2028 tsubst_flags_t complain)
2030 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
2031 the first operand is always the one to be used if both operands
2032 are equal, so we know what conditional expression this used to be. */
2033 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
2035 tree op0 = TREE_OPERAND (t, 0);
2036 tree op1 = TREE_OPERAND (t, 1);
2038 /* The following code is incorrect if either operand side-effects. */
2039 gcc_assert (!TREE_SIDE_EFFECTS (op0)
2040 && !TREE_SIDE_EFFECTS (op1));
2042 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
2043 ? LE_EXPR : GE_EXPR),
2044 op0, TREE_CODE (op0),
2045 op1, TREE_CODE (op1),
2048 cp_build_unary_op (code, op0, 0, complain),
2049 cp_build_unary_op (code, op1, 0, complain),
2054 build_conditional_expr (TREE_OPERAND (t, 0),
2055 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
2057 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
2062 /* Given the TYPE of an anonymous union field inside T, return the
2063 FIELD_DECL for the field. If not found return NULL_TREE. Because
2064 anonymous unions can nest, we must also search all anonymous unions
2065 that are directly reachable. */
2068 lookup_anon_field (tree t, tree type)
2072 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2074 if (TREE_STATIC (field))
2076 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
2079 /* If we find it directly, return the field. */
2080 if (DECL_NAME (field) == NULL_TREE
2081 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
2086 /* Otherwise, it could be nested, search harder. */
2087 if (DECL_NAME (field) == NULL_TREE
2088 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2090 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
2098 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
2099 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
2100 non-NULL, it indicates the path to the base used to name MEMBER.
2101 If PRESERVE_REFERENCE is true, the expression returned will have
2102 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
2103 returned will have the type referred to by the reference.
2105 This function does not perform access control; that is either done
2106 earlier by the parser when the name of MEMBER is resolved to MEMBER
2107 itself, or later when overload resolution selects one of the
2108 functions indicated by MEMBER. */
2111 build_class_member_access_expr (tree object, tree member,
2112 tree access_path, bool preserve_reference,
2113 tsubst_flags_t complain)
2117 tree result = NULL_TREE;
2119 if (error_operand_p (object) || error_operand_p (member))
2120 return error_mark_node;
2122 gcc_assert (DECL_P (member) || BASELINK_P (member));
2126 The type of the first expression shall be "class object" (of a
2128 object_type = TREE_TYPE (object);
2129 if (!currently_open_class (object_type)
2130 && !complete_type_or_maybe_complain (object_type, object, complain))
2131 return error_mark_node;
2132 if (!CLASS_TYPE_P (object_type))
2134 if (complain & tf_error)
2136 if (POINTER_TYPE_P (object_type)
2137 && CLASS_TYPE_P (TREE_TYPE (object_type)))
2138 error ("request for member %qD in %qE, which is of pointer "
2139 "type %qT (maybe you meant to use %<->%> ?)",
2140 member, object, object_type);
2142 error ("request for member %qD in %qE, which is of non-class "
2143 "type %qT", member, object, object_type);
2145 return error_mark_node;
2148 /* The standard does not seem to actually say that MEMBER must be a
2149 member of OBJECT_TYPE. However, that is clearly what is
2151 if (DECL_P (member))
2153 member_scope = DECL_CLASS_CONTEXT (member);
2155 if (TREE_DEPRECATED (member))
2156 warn_deprecated_use (member, NULL_TREE);
2159 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
2160 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
2161 presently be the anonymous union. Go outwards until we find a
2162 type related to OBJECT_TYPE. */
2163 while (ANON_AGGR_TYPE_P (member_scope)
2164 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
2166 member_scope = TYPE_CONTEXT (member_scope);
2167 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
2169 if (complain & tf_error)
2171 if (TREE_CODE (member) == FIELD_DECL)
2172 error ("invalid use of nonstatic data member %qE", member);
2174 error ("%qD is not a member of %qT", member, object_type);
2176 return error_mark_node;
2179 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
2180 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
2181 in the front end; only _DECLs and _REFs are lvalues in the back end. */
2183 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
2185 object = cp_build_indirect_ref (temp, RO_NULL, complain);
2188 /* In [expr.ref], there is an explicit list of the valid choices for
2189 MEMBER. We check for each of those cases here. */
2190 if (TREE_CODE (member) == VAR_DECL)
2192 /* A static data member. */
2194 mark_exp_read (object);
2195 /* If OBJECT has side-effects, they are supposed to occur. */
2196 if (TREE_SIDE_EFFECTS (object))
2197 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
2199 else if (TREE_CODE (member) == FIELD_DECL)
2201 /* A non-static data member. */
2206 null_object_p = (TREE_CODE (object) == INDIRECT_REF
2207 && integer_zerop (TREE_OPERAND (object, 0)));
2209 /* Convert OBJECT to the type of MEMBER. */
2210 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
2211 TYPE_MAIN_VARIANT (member_scope)))
2216 binfo = lookup_base (access_path ? access_path : object_type,
2217 member_scope, ba_unique, &kind);
2218 if (binfo == error_mark_node)
2219 return error_mark_node;
2221 /* It is invalid to try to get to a virtual base of a
2222 NULL object. The most common cause is invalid use of
2224 if (null_object_p && kind == bk_via_virtual)
2226 if (complain & tf_error)
2228 error ("invalid access to non-static data member %qD of "
2231 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
2233 return error_mark_node;
2236 /* Convert to the base. */
2237 object = build_base_path (PLUS_EXPR, object, binfo,
2238 /*nonnull=*/1, complain);
2239 /* If we found the base successfully then we should be able
2240 to convert to it successfully. */
2241 gcc_assert (object != error_mark_node);
2244 /* Complain about other invalid uses of offsetof, even though they will
2245 give the right answer. Note that we complain whether or not they
2246 actually used the offsetof macro, since there's no way to know at this
2247 point. So we just give a warning, instead of a pedwarn. */
2248 /* Do not produce this warning for base class field references, because
2249 we know for a fact that didn't come from offsetof. This does occur
2250 in various testsuite cases where a null object is passed where a
2251 vtable access is required. */
2252 if (null_object_p && warn_invalid_offsetof
2253 && CLASSTYPE_NON_STD_LAYOUT (object_type)
2254 && !DECL_FIELD_IS_BASE (member)
2255 && cp_unevaluated_operand == 0
2256 && (complain & tf_warning))
2258 warning (OPT_Winvalid_offsetof,
2259 "invalid access to non-static data member %qD "
2260 " of NULL object", member);
2261 warning (OPT_Winvalid_offsetof,
2262 "(perhaps the %<offsetof%> macro was used incorrectly)");
2265 /* If MEMBER is from an anonymous aggregate, we have converted
2266 OBJECT so that it refers to the class containing the
2267 anonymous union. Generate a reference to the anonymous union
2268 itself, and recur to find MEMBER. */
2269 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2270 /* When this code is called from build_field_call, the
2271 object already has the type of the anonymous union.
2272 That is because the COMPONENT_REF was already
2273 constructed, and was then disassembled before calling
2274 build_field_call. After the function-call code is
2275 cleaned up, this waste can be eliminated. */
2276 && (!same_type_ignoring_top_level_qualifiers_p
2277 (TREE_TYPE (object), DECL_CONTEXT (member))))
2279 tree anonymous_union;
2281 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2282 DECL_CONTEXT (member));
2283 object = build_class_member_access_expr (object,
2285 /*access_path=*/NULL_TREE,
2290 /* Compute the type of the field, as described in [expr.ref]. */
2291 type_quals = TYPE_UNQUALIFIED;
2292 member_type = TREE_TYPE (member);
2293 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2295 type_quals = (cp_type_quals (member_type)
2296 | cp_type_quals (object_type));
2298 /* A field is const (volatile) if the enclosing object, or the
2299 field itself, is const (volatile). But, a mutable field is
2300 not const, even within a const object. */
2301 if (DECL_MUTABLE_P (member))
2302 type_quals &= ~TYPE_QUAL_CONST;
2303 member_type = cp_build_qualified_type (member_type, type_quals);
2306 result = build3 (COMPONENT_REF, member_type, object, member,
2308 result = fold_if_not_in_template (result);
2310 /* Mark the expression const or volatile, as appropriate. Even
2311 though we've dealt with the type above, we still have to mark the
2312 expression itself. */
2313 if (type_quals & TYPE_QUAL_CONST)
2314 TREE_READONLY (result) = 1;
2315 if (type_quals & TYPE_QUAL_VOLATILE)
2316 TREE_THIS_VOLATILE (result) = 1;
2318 else if (BASELINK_P (member))
2320 /* The member is a (possibly overloaded) member function. */
2324 /* If the MEMBER is exactly one static member function, then we
2325 know the type of the expression. Otherwise, we must wait
2326 until overload resolution has been performed. */
2327 functions = BASELINK_FUNCTIONS (member);
2328 if (TREE_CODE (functions) == FUNCTION_DECL
2329 && DECL_STATIC_FUNCTION_P (functions))
2330 type = TREE_TYPE (functions);
2332 type = unknown_type_node;
2333 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2334 base. That will happen when the function is called. */
2335 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2337 else if (TREE_CODE (member) == CONST_DECL)
2339 /* The member is an enumerator. */
2341 /* If OBJECT has side-effects, they are supposed to occur. */
2342 if (TREE_SIDE_EFFECTS (object))
2343 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2348 if (complain & tf_error)
2349 error ("invalid use of %qD", member);
2350 return error_mark_node;
2353 if (!preserve_reference)
2356 If E2 is declared to have type "reference to T", then ... the
2357 type of E1.E2 is T. */
2358 result = convert_from_reference (result);
2363 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2364 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2367 lookup_destructor (tree object, tree scope, tree dtor_name)
2369 tree object_type = TREE_TYPE (object);
2370 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2373 if (scope && !check_dtor_name (scope, dtor_type))
2375 error ("qualified type %qT does not match destructor name ~%qT",
2377 return error_mark_node;
2379 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2381 /* In a template, names we can't find a match for are still accepted
2382 destructor names, and we check them here. */
2383 if (check_dtor_name (object_type, dtor_type))
2384 dtor_type = object_type;
2387 error ("object type %qT does not match destructor name ~%qT",
2388 object_type, dtor_type);
2389 return error_mark_node;
2393 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2395 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2396 TYPE_MAIN_VARIANT (object_type), dtor_type);
2397 return error_mark_node;
2399 expr = lookup_member (dtor_type, complete_dtor_identifier,
2400 /*protect=*/1, /*want_type=*/false);
2401 expr = (adjust_result_of_qualified_name_lookup
2402 (expr, dtor_type, object_type));
2406 /* An expression of the form "A::template B" has been resolved to
2407 DECL. Issue a diagnostic if B is not a template or template
2411 check_template_keyword (tree decl)
2413 /* The standard says:
2417 If a name prefixed by the keyword template is not a member
2418 template, the program is ill-formed.
2420 DR 228 removed the restriction that the template be a member
2423 DR 96, if accepted would add the further restriction that explicit
2424 template arguments must be provided if the template keyword is
2425 used, but, as of 2005-10-16, that DR is still in "drafting". If
2426 this DR is accepted, then the semantic checks here can be
2427 simplified, as the entity named must in fact be a template
2428 specialization, rather than, as at present, a set of overloaded
2429 functions containing at least one template function. */
2430 if (TREE_CODE (decl) != TEMPLATE_DECL
2431 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2433 if (!is_overloaded_fn (decl))
2434 permerror (input_location, "%qD is not a template", decl);
2439 if (BASELINK_P (fns))
2440 fns = BASELINK_FUNCTIONS (fns);
2443 tree fn = OVL_CURRENT (fns);
2444 if (TREE_CODE (fn) == TEMPLATE_DECL
2445 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2447 if (TREE_CODE (fn) == FUNCTION_DECL
2448 && DECL_USE_TEMPLATE (fn)
2449 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2451 fns = OVL_NEXT (fns);
2454 permerror (input_location, "%qD is not a template", decl);
2459 /* This function is called by the parser to process a class member
2460 access expression of the form OBJECT.NAME. NAME is a node used by
2461 the parser to represent a name; it is not yet a DECL. It may,
2462 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2463 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2464 there is no reason to do the lookup twice, so the parser keeps the
2465 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2466 be a template via the use of the "A::template B" syntax. */
2469 finish_class_member_access_expr (tree object, tree name, bool template_p,
2470 tsubst_flags_t complain)
2475 tree access_path = NULL_TREE;
2476 tree orig_object = object;
2477 tree orig_name = name;
2479 if (object == error_mark_node || name == error_mark_node)
2480 return error_mark_node;
2482 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2483 if (!objc_is_public (object, name))
2484 return error_mark_node;
2486 object_type = TREE_TYPE (object);
2488 if (processing_template_decl)
2490 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2491 dependent_type_p (object_type)
2492 /* If NAME is just an IDENTIFIER_NODE, then the expression
2494 || TREE_CODE (object) == IDENTIFIER_NODE
2495 /* If NAME is "f<args>", where either 'f' or 'args' is
2496 dependent, then the expression is dependent. */
2497 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2498 && dependent_template_id_p (TREE_OPERAND (name, 0),
2499 TREE_OPERAND (name, 1)))
2500 /* If NAME is "T::X" where "T" is dependent, then the
2501 expression is dependent. */
2502 || (TREE_CODE (name) == SCOPE_REF
2503 && TYPE_P (TREE_OPERAND (name, 0))
2504 && dependent_type_p (TREE_OPERAND (name, 0))))
2505 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2506 object = build_non_dependent_expr (object);
2508 else if (c_dialect_objc ()
2509 && TREE_CODE (name) == IDENTIFIER_NODE
2510 && (expr = objc_maybe_build_component_ref (object, name)))
2515 The type of the first expression shall be "class object" (of a
2517 if (!currently_open_class (object_type)
2518 && !complete_type_or_maybe_complain (object_type, object, complain))
2519 return error_mark_node;
2520 if (!CLASS_TYPE_P (object_type))
2522 if (complain & tf_error)
2524 if (POINTER_TYPE_P (object_type)
2525 && CLASS_TYPE_P (TREE_TYPE (object_type)))
2526 error ("request for member %qD in %qE, which is of pointer "
2527 "type %qT (maybe you meant to use %<->%> ?)",
2528 name, object, object_type);
2530 error ("request for member %qD in %qE, which is of non-class "
2531 "type %qT", name, object, object_type);
2533 return error_mark_node;
2536 if (BASELINK_P (name))
2537 /* A member function that has already been looked up. */
2541 bool is_template_id = false;
2542 tree template_args = NULL_TREE;
2545 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2547 is_template_id = true;
2548 template_args = TREE_OPERAND (name, 1);
2549 name = TREE_OPERAND (name, 0);
2551 if (TREE_CODE (name) == OVERLOAD)
2552 name = DECL_NAME (get_first_fn (name));
2553 else if (DECL_P (name))
2554 name = DECL_NAME (name);
2557 if (TREE_CODE (name) == SCOPE_REF)
2559 /* A qualified name. The qualifying class or namespace `S'
2560 has already been looked up; it is either a TYPE or a
2562 scope = TREE_OPERAND (name, 0);
2563 name = TREE_OPERAND (name, 1);
2565 /* If SCOPE is a namespace, then the qualified name does not
2566 name a member of OBJECT_TYPE. */
2567 if (TREE_CODE (scope) == NAMESPACE_DECL)
2569 if (complain & tf_error)
2570 error ("%<%D::%D%> is not a member of %qT",
2571 scope, name, object_type);
2572 return error_mark_node;
2575 gcc_assert (CLASS_TYPE_P (scope));
2576 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2577 || TREE_CODE (name) == BIT_NOT_EXPR);
2579 if (constructor_name_p (name, scope))
2581 if (complain & tf_error)
2582 error ("cannot call constructor %<%T::%D%> directly",
2584 return error_mark_node;
2587 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2588 access_path = lookup_base (object_type, scope, ba_check, NULL);
2589 if (access_path == error_mark_node)
2590 return error_mark_node;
2593 if (complain & tf_error)
2594 error ("%qT is not a base of %qT", scope, object_type);
2595 return error_mark_node;
2601 access_path = object_type;
2604 if (TREE_CODE (name) == BIT_NOT_EXPR)
2605 member = lookup_destructor (object, scope, name);
2608 /* Look up the member. */
2609 member = lookup_member (access_path, name, /*protect=*/1,
2610 /*want_type=*/false);
2611 if (member == NULL_TREE)
2613 if (complain & tf_error)
2614 error ("%qD has no member named %qE",
2615 TREE_CODE (access_path) == TREE_BINFO
2616 ? TREE_TYPE (access_path) : object_type, name);
2617 return error_mark_node;
2619 if (member == error_mark_node)
2620 return error_mark_node;
2625 tree templ = member;
2627 if (BASELINK_P (templ))
2628 templ = lookup_template_function (templ, template_args);
2631 if (complain & tf_error)
2632 error ("%qD is not a member template function", name);
2633 return error_mark_node;
2638 if (TREE_DEPRECATED (member))
2639 warn_deprecated_use (member, NULL_TREE);
2642 check_template_keyword (member);
2644 expr = build_class_member_access_expr (object, member, access_path,
2645 /*preserve_reference=*/false,
2647 if (processing_template_decl && expr != error_mark_node)
2649 if (BASELINK_P (member))
2651 if (TREE_CODE (orig_name) == SCOPE_REF)
2652 BASELINK_QUALIFIED_P (member) = 1;
2655 return build_min_non_dep (COMPONENT_REF, expr,
2656 orig_object, orig_name,
2663 /* Return an expression for the MEMBER_NAME field in the internal
2664 representation of PTRMEM, a pointer-to-member function. (Each
2665 pointer-to-member function type gets its own RECORD_TYPE so it is
2666 more convenient to access the fields by name than by FIELD_DECL.)
2667 This routine converts the NAME to a FIELD_DECL and then creates the
2668 node for the complete expression. */
2671 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2677 /* This code is a stripped down version of
2678 build_class_member_access_expr. It does not work to use that
2679 routine directly because it expects the object to be of class
2681 ptrmem_type = TREE_TYPE (ptrmem);
2682 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2683 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2684 /*want_type=*/false);
2685 member_type = cp_build_qualified_type (TREE_TYPE (member),
2686 cp_type_quals (ptrmem_type));
2687 return fold_build3_loc (input_location,
2688 COMPONENT_REF, member_type,
2689 ptrmem, member, NULL_TREE);
2692 /* Given an expression PTR for a pointer, return an expression
2693 for the value pointed to.
2694 ERRORSTRING is the name of the operator to appear in error messages.
2696 This function may need to overload OPERATOR_FNNAME.
2697 Must also handle REFERENCE_TYPEs for C++. */
2700 build_x_indirect_ref (tree expr, ref_operator errorstring,
2701 tsubst_flags_t complain)
2703 tree orig_expr = expr;
2706 if (processing_template_decl)
2708 /* Retain the type if we know the operand is a pointer. */
2709 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
2710 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
2711 if (type_dependent_expression_p (expr))
2712 return build_min_nt (INDIRECT_REF, expr);
2713 expr = build_non_dependent_expr (expr);
2716 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2717 NULL_TREE, /*overload=*/NULL, complain);
2719 rval = cp_build_indirect_ref (expr, errorstring, complain);
2721 if (processing_template_decl && rval != error_mark_node)
2722 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2727 /* Helper function called from c-common. */
2729 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2730 tree ptr, ref_operator errorstring)
2732 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2736 cp_build_indirect_ref (tree ptr, ref_operator errorstring,
2737 tsubst_flags_t complain)
2741 if (ptr == error_mark_node)
2742 return error_mark_node;
2744 if (ptr == current_class_ptr)
2745 return current_class_ref;
2747 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2748 ? ptr : decay_conversion (ptr));
2749 type = TREE_TYPE (pointer);
2751 if (POINTER_TYPE_P (type))
2755 If the type of the expression is "pointer to T," the type
2756 of the result is "T." */
2757 tree t = TREE_TYPE (type);
2759 if (CONVERT_EXPR_P (ptr)
2760 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2762 /* If a warning is issued, mark it to avoid duplicates from
2763 the backend. This only needs to be done at
2764 warn_strict_aliasing > 2. */
2765 if (warn_strict_aliasing > 2)
2766 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2767 type, TREE_OPERAND (ptr, 0)))
2768 TREE_NO_WARNING (ptr) = 1;
2771 if (VOID_TYPE_P (t))
2773 /* A pointer to incomplete type (other than cv void) can be
2774 dereferenced [expr.unary.op]/1 */
2775 if (complain & tf_error)
2776 error ("%qT is not a pointer-to-object type", type);
2777 return error_mark_node;
2779 else if (TREE_CODE (pointer) == ADDR_EXPR
2780 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2781 /* The POINTER was something like `&x'. We simplify `*&x' to
2783 return TREE_OPERAND (pointer, 0);
2786 tree ref = build1 (INDIRECT_REF, t, pointer);
2788 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2789 so that we get the proper error message if the result is used
2790 to assign to. Also, &* is supposed to be a no-op. */
2791 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2792 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2793 TREE_SIDE_EFFECTS (ref)
2794 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2798 else if (!(complain & tf_error))
2799 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2801 /* `pointer' won't be an error_mark_node if we were given a
2802 pointer to member, so it's cool to check for this here. */
2803 else if (TYPE_PTR_TO_MEMBER_P (type))
2804 switch (errorstring)
2806 case RO_ARRAY_INDEXING:
2807 error ("invalid use of array indexing on pointer to member");
2810 error ("invalid use of unary %<*%> on pointer to member");
2812 case RO_IMPLICIT_CONVERSION:
2813 error ("invalid use of implicit conversion on pointer to member");
2818 else if (pointer != error_mark_node)
2819 invalid_indirection_error (input_location, type, errorstring);
2821 return error_mark_node;
2824 /* This handles expressions of the form "a[i]", which denotes
2827 This is logically equivalent in C to *(a+i), but we may do it differently.
2828 If A is a variable or a member, we generate a primitive ARRAY_REF.
2829 This avoids forcing the array out of registers, and can work on
2830 arrays that are not lvalues (for example, members of structures returned
2833 If INDEX is of some user-defined type, it must be converted to
2834 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2835 will inherit the type of the array, which will be some pointer type.
2837 LOC is the location to use in building the array reference. */
2840 cp_build_array_ref (location_t loc, tree array, tree idx,
2841 tsubst_flags_t complain)
2847 if (complain & tf_error)
2848 error_at (loc, "subscript missing in array reference");
2849 return error_mark_node;
2852 if (TREE_TYPE (array) == error_mark_node
2853 || TREE_TYPE (idx) == error_mark_node)
2854 return error_mark_node;
2856 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2858 switch (TREE_CODE (array))
2862 tree value = cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
2864 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2865 TREE_OPERAND (array, 0), value);
2866 SET_EXPR_LOCATION (ret, loc);
2871 ret = build_conditional_expr
2872 (TREE_OPERAND (array, 0),
2873 cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
2875 cp_build_array_ref (loc, TREE_OPERAND (array, 2), idx,
2877 tf_warning_or_error);
2878 protected_set_expr_location (ret, loc);
2885 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2889 warn_array_subscript_with_type_char (idx);
2891 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2893 if (complain & tf_error)
2894 error_at (loc, "array subscript is not an integer");
2895 return error_mark_node;
2898 /* Apply integral promotions *after* noticing character types.
2899 (It is unclear why we do these promotions -- the standard
2900 does not say that we should. In fact, the natural thing would
2901 seem to be to convert IDX to ptrdiff_t; we're performing
2902 pointer arithmetic.) */
2903 idx = perform_integral_promotions (idx);
2905 /* An array that is indexed by a non-constant
2906 cannot be stored in a register; we must be able to do
2907 address arithmetic on its address.
2908 Likewise an array of elements of variable size. */
2909 if (TREE_CODE (idx) != INTEGER_CST
2910 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2911 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2914 if (!cxx_mark_addressable (array))
2915 return error_mark_node;
2918 /* An array that is indexed by a constant value which is not within
2919 the array bounds cannot be stored in a register either; because we
2920 would get a crash in store_bit_field/extract_bit_field when trying
2921 to access a non-existent part of the register. */
2922 if (TREE_CODE (idx) == INTEGER_CST
2923 && TYPE_DOMAIN (TREE_TYPE (array))
2924 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2926 if (!cxx_mark_addressable (array))
2927 return error_mark_node;
2930 if (!lvalue_p (array) && (complain & tf_error))
2931 pedwarn (loc, OPT_pedantic,
2932 "ISO C++ forbids subscripting non-lvalue array");
2934 /* Note in C++ it is valid to subscript a `register' array, since
2935 it is valid to take the address of something with that
2936 storage specification. */
2940 while (TREE_CODE (foo) == COMPONENT_REF)
2941 foo = TREE_OPERAND (foo, 0);
2942 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo)
2943 && (complain & tf_warning))
2944 warning_at (loc, OPT_Wextra,
2945 "subscripting array declared %<register%>");
2948 type = TREE_TYPE (TREE_TYPE (array));
2949 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2950 /* Array ref is const/volatile if the array elements are
2951 or if the array is.. */
2952 TREE_READONLY (rval)
2953 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2954 TREE_SIDE_EFFECTS (rval)
2955 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2956 TREE_THIS_VOLATILE (rval)
2957 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2958 ret = require_complete_type_sfinae (fold_if_not_in_template (rval),
2960 protected_set_expr_location (ret, loc);
2965 tree ar = default_conversion (array);
2966 tree ind = default_conversion (idx);
2968 /* Put the integer in IND to simplify error checking. */
2969 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2976 if (ar == error_mark_node)
2979 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2981 if (complain & tf_error)
2982 error_at (loc, "subscripted value is neither array nor pointer");
2983 return error_mark_node;
2985 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2987 if (complain & tf_error)
2988 error_at (loc, "array subscript is not an integer");
2989 return error_mark_node;
2992 warn_array_subscript_with_type_char (idx);
2994 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2999 protected_set_expr_location (ret, loc);
3004 /* Entry point for Obj-C++. */
3007 build_array_ref (location_t loc, tree array, tree idx)
3009 return cp_build_array_ref (loc, array, idx, tf_warning_or_error);
3012 /* Resolve a pointer to member function. INSTANCE is the object
3013 instance to use, if the member points to a virtual member.
3015 This used to avoid checking for virtual functions if basetype
3016 has no virtual functions, according to an earlier ANSI draft.
3017 With the final ISO C++ rules, such an optimization is
3018 incorrect: A pointer to a derived member can be static_cast
3019 to pointer-to-base-member, as long as the dynamic object
3020 later has the right member. */
3023 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
3025 if (TREE_CODE (function) == OFFSET_REF)
3026 function = TREE_OPERAND (function, 1);
3028 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
3030 tree idx, delta, e1, e2, e3, vtbl, basetype;
3031 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
3033 tree instance_ptr = *instance_ptrptr;
3034 tree instance_save_expr = 0;
3035 if (instance_ptr == error_mark_node)
3037 if (TREE_CODE (function) == PTRMEM_CST)
3039 /* Extracting the function address from a pmf is only
3040 allowed with -Wno-pmf-conversions. It only works for
3042 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
3043 e1 = convert (fntype, e1);
3048 error ("object missing in use of %qE", function);
3049 return error_mark_node;
3053 if (TREE_SIDE_EFFECTS (instance_ptr))
3054 instance_ptr = instance_save_expr = save_expr (instance_ptr);
3056 if (TREE_SIDE_EFFECTS (function))
3057 function = save_expr (function);
3059 /* Start by extracting all the information from the PMF itself. */
3060 e3 = pfn_from_ptrmemfunc (function);
3061 delta = delta_from_ptrmemfunc (function);
3062 idx = build1 (NOP_EXPR, vtable_index_type, e3);
3063 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
3065 case ptrmemfunc_vbit_in_pfn:
3066 e1 = cp_build_binary_op (input_location,
3067 BIT_AND_EXPR, idx, integer_one_node,
3068 tf_warning_or_error);
3069 idx = cp_build_binary_op (input_location,
3070 MINUS_EXPR, idx, integer_one_node,
3071 tf_warning_or_error);
3074 case ptrmemfunc_vbit_in_delta:
3075 e1 = cp_build_binary_op (input_location,
3076 BIT_AND_EXPR, delta, integer_one_node,
3077 tf_warning_or_error);
3078 delta = cp_build_binary_op (input_location,
3079 RSHIFT_EXPR, delta, integer_one_node,
3080 tf_warning_or_error);
3087 /* Convert down to the right base before using the instance. A
3088 special case is that in a pointer to member of class C, C may
3089 be incomplete. In that case, the function will of course be
3090 a member of C, and no conversion is required. In fact,
3091 lookup_base will fail in that case, because incomplete
3092 classes do not have BINFOs. */
3093 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
3094 if (!same_type_ignoring_top_level_qualifiers_p
3095 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
3097 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
3098 basetype, ba_check, NULL);
3099 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
3100 1, tf_warning_or_error);
3101 if (instance_ptr == error_mark_node)
3102 return error_mark_node;
3104 /* ...and then the delta in the PMF. */
3105 instance_ptr = fold_build_pointer_plus (instance_ptr, delta);
3107 /* Hand back the adjusted 'this' argument to our caller. */
3108 *instance_ptrptr = instance_ptr;
3110 /* Next extract the vtable pointer from the object. */
3111 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
3113 vtbl = cp_build_indirect_ref (vtbl, RO_NULL, tf_warning_or_error);
3114 /* If the object is not dynamic the access invokes undefined
3115 behavior. As it is not executed in this case silence the
3116 spurious warnings it may provoke. */
3117 TREE_NO_WARNING (vtbl) = 1;
3119 /* Finally, extract the function pointer from the vtable. */
3120 e2 = fold_build_pointer_plus_loc (input_location, vtbl, idx);
3121 e2 = cp_build_indirect_ref (e2, RO_NULL, tf_warning_or_error);
3122 TREE_CONSTANT (e2) = 1;
3124 /* When using function descriptors, the address of the
3125 vtable entry is treated as a function pointer. */
3126 if (TARGET_VTABLE_USES_DESCRIPTORS)
3127 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
3128 cp_build_addr_expr (e2, tf_warning_or_error));
3130 e2 = fold_convert (TREE_TYPE (e3), e2);
3131 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
3133 /* Make sure this doesn't get evaluated first inside one of the
3134 branches of the COND_EXPR. */
3135 if (instance_save_expr)
3136 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
3137 instance_save_expr, e1);
3144 /* Used by the C-common bits. */
3146 build_function_call (location_t loc ATTRIBUTE_UNUSED,
3147 tree function, tree params)
3149 return cp_build_function_call (function, params, tf_warning_or_error);
3152 /* Used by the C-common bits. */
3154 build_function_call_vec (location_t loc ATTRIBUTE_UNUSED,
3155 tree function, VEC(tree,gc) *params,
3156 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
3158 VEC(tree,gc) *orig_params = params;
3159 tree ret = cp_build_function_call_vec (function, ¶ms,
3160 tf_warning_or_error);
3162 /* cp_build_function_call_vec can reallocate PARAMS by adding
3163 default arguments. That should never happen here. Verify
3165 gcc_assert (params == orig_params);
3170 /* Build a function call using a tree list of arguments. */
3173 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
3178 vec = make_tree_vector ();
3179 for (; params != NULL_TREE; params = TREE_CHAIN (params))
3180 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
3181 ret = cp_build_function_call_vec (function, &vec, complain);
3182 release_tree_vector (vec);
3186 /* Build a function call using varargs. */
3189 cp_build_function_call_nary (tree function, tsubst_flags_t complain, ...)
3195 vec = make_tree_vector ();
3196 va_start (args, complain);
3197 for (t = va_arg (args, tree); t != NULL_TREE; t = va_arg (args, tree))
3198 VEC_safe_push (tree, gc, vec, t);
3200 ret = cp_build_function_call_vec (function, &vec, complain);
3201 release_tree_vector (vec);
3205 /* Build a function call using a vector of arguments. PARAMS may be
3206 NULL if there are no parameters. This changes the contents of
3210 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
3211 tsubst_flags_t complain)
3213 tree fntype, fndecl;
3215 tree original = function;
3219 VEC(tree,gc) *allocated = NULL;
3222 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
3223 expressions, like those used for ObjC messenger dispatches. */
3224 if (params != NULL && !VEC_empty (tree, *params))
3225 function = objc_rewrite_function_call (function,
3226 VEC_index (tree, *params, 0));
3228 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3229 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
3230 if (TREE_CODE (function) == NOP_EXPR
3231 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
3232 function = TREE_OPERAND (function, 0);
3234 if (TREE_CODE (function) == FUNCTION_DECL)
3236 mark_used (function);
3239 /* Convert anything with function type to a pointer-to-function. */
3240 if (DECL_MAIN_P (function) && (complain & tf_error))
3241 pedwarn (input_location, OPT_pedantic,
3242 "ISO C++ forbids calling %<::main%> from within program");
3244 function = build_addr_func (function);
3250 function = build_addr_func (function);
3253 if (function == error_mark_node)
3254 return error_mark_node;
3256 fntype = TREE_TYPE (function);
3258 if (TYPE_PTRMEMFUNC_P (fntype))
3260 if (complain & tf_error)
3261 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
3262 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
3263 original, original);
3264 return error_mark_node;
3267 is_method = (TREE_CODE (fntype) == POINTER_TYPE
3268 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
3270 if (!((TREE_CODE (fntype) == POINTER_TYPE
3271 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
3273 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
3275 if (complain & tf_error)
3276 error ("%qE cannot be used as a function", original);
3277 return error_mark_node;
3280 /* fntype now gets the type of function pointed to. */
3281 fntype = TREE_TYPE (fntype);
3282 parm_types = TYPE_ARG_TYPES (fntype);
3286 allocated = make_tree_vector ();
3287 params = &allocated;
3290 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
3293 return error_mark_node;
3295 argarray = VEC_address (tree, *params);
3297 /* Check for errors in format strings and inappropriately
3299 check_function_arguments (fntype, nargs, argarray);
3301 ret = build_cxx_call (function, nargs, argarray);
3303 if (allocated != NULL)
3304 release_tree_vector (allocated);
3309 /* Subroutine of convert_arguments.
3310 Warn about wrong number of args are genereted. */
3313 warn_args_num (location_t loc, tree fndecl, bool too_many_p)
3317 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3319 if (DECL_NAME (fndecl) == NULL_TREE
3320 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3323 ? G_("too many arguments to constructor %q#D")
3324 : G_("too few arguments to constructor %q#D"),
3329 ? G_("too many arguments to member function %q#D")
3330 : G_("too few arguments to member function %q#D"),
3336 ? G_("too many arguments to function %q#D")
3337 : G_("too few arguments to function %q#D"),
3339 inform (DECL_SOURCE_LOCATION (fndecl),
3344 if (c_dialect_objc () && objc_message_selector ())
3347 ? G_("too many arguments to method %q#D")
3348 : G_("too few arguments to method %q#D"),
3349 objc_message_selector ());
3351 error_at (loc, too_many_p ? G_("too many arguments to function")
3352 : G_("too few arguments to function"));
3356 /* Convert the actual parameter expressions in the list VALUES to the
3357 types in the list TYPELIST. The converted expressions are stored
3358 back in the VALUES vector.
3359 If parmdecls is exhausted, or when an element has NULL as its type,
3360 perform the default conversions.
3362 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3364 This is also where warnings about wrong number of args are generated.
3366 Returns the actual number of arguments processed (which might be less
3367 than the length of the vector), or -1 on error.
3369 In C++, unspecified trailing parameters can be filled in with their
3370 default arguments, if such were specified. Do so here. */
3373 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3374 int flags, tsubst_flags_t complain)
3379 /* Argument passing is always copy-initialization. */
3380 flags |= LOOKUP_ONLYCONVERTING;
3382 for (i = 0, typetail = typelist;
3383 i < VEC_length (tree, *values);
3386 tree type = typetail ? TREE_VALUE (typetail) : 0;
3387 tree val = VEC_index (tree, *values, i);
3389 if (val == error_mark_node || type == error_mark_node)
3392 if (type == void_type_node)
3394 if (complain & tf_error)
3396 warn_args_num (input_location, fndecl, /*too_many_p=*/true);
3403 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3404 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3405 if (TREE_CODE (val) == NOP_EXPR
3406 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3407 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3408 val = TREE_OPERAND (val, 0);
3410 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3412 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3413 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3414 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3415 val = decay_conversion (val);
3418 if (val == error_mark_node)
3423 /* Formal parm type is specified by a function prototype. */
3426 if (!COMPLETE_TYPE_P (complete_type (type)))
3428 if (complain & tf_error)
3431 error ("parameter %P of %qD has incomplete type %qT",
3434 error ("parameter %P has incomplete type %qT", i, type);
3436 parmval = error_mark_node;
3440 parmval = convert_for_initialization
3441 (NULL_TREE, type, val, flags,
3442 ICR_ARGPASS, fndecl, i, complain);
3443 parmval = convert_for_arg_passing (type, parmval);
3446 if (parmval == error_mark_node)
3449 VEC_replace (tree, *values, i, parmval);
3453 if (fndecl && DECL_BUILT_IN (fndecl)
3454 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3455 /* Don't do ellipsis conversion for __built_in_constant_p
3456 as this will result in spurious errors for non-trivial
3458 val = require_complete_type_sfinae (val, complain);
3460 val = convert_arg_to_ellipsis (val);
3462 VEC_replace (tree, *values, i, val);
3466 typetail = TREE_CHAIN (typetail);
3469 if (typetail != 0 && typetail != void_list_node)
3471 /* See if there are default arguments that can be used. Because
3472 we hold default arguments in the FUNCTION_TYPE (which is so
3473 wrong), we can see default parameters here from deduced
3474 contexts (and via typeof) for indirect function calls.
3475 Fortunately we know whether we have a function decl to
3476 provide default arguments in a language conformant
3478 if (fndecl && TREE_PURPOSE (typetail)
3479 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3481 for (; typetail != void_list_node; ++i)
3484 = convert_default_arg (TREE_VALUE (typetail),
3485 TREE_PURPOSE (typetail),
3488 if (parmval == error_mark_node)
3491 VEC_safe_push (tree, gc, *values, parmval);
3492 typetail = TREE_CHAIN (typetail);
3493 /* ends with `...'. */
3494 if (typetail == NULL_TREE)
3500 if (complain & tf_error)
3501 warn_args_num (input_location, fndecl, /*too_many_p=*/false);
3509 /* Build a binary-operation expression, after performing default
3510 conversions on the operands. CODE is the kind of expression to
3511 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3512 are the tree codes which correspond to ARG1 and ARG2 when issuing
3513 warnings about possibly misplaced parentheses. They may differ
3514 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3515 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3516 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3517 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3518 ARG2_CODE as ERROR_MARK. */
3521 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3522 tree arg2, enum tree_code arg2_code, tree *overload,
3523 tsubst_flags_t complain)
3532 if (processing_template_decl)
3534 if (type_dependent_expression_p (arg1)
3535 || type_dependent_expression_p (arg2))
3536 return build_min_nt (code, arg1, arg2);
3537 arg1 = build_non_dependent_expr (arg1);
3538 arg2 = build_non_dependent_expr (arg2);
3541 if (code == DOTSTAR_EXPR)
3542 expr = build_m_component_ref (arg1, arg2);
3544 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3545 overload, complain);
3547 /* Check for cases such as x+y<<z which users are likely to
3548 misinterpret. But don't warn about obj << x + y, since that is a
3549 common idiom for I/O. */
3550 if (warn_parentheses
3551 && (complain & tf_warning)
3552 && !processing_template_decl
3553 && !error_operand_p (arg1)
3554 && !error_operand_p (arg2)
3555 && (code != LSHIFT_EXPR
3556 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3557 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3559 if (processing_template_decl && expr != error_mark_node)
3560 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3565 /* Build and return an ARRAY_REF expression. */
3568 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3570 tree orig_arg1 = arg1;
3571 tree orig_arg2 = arg2;
3574 if (processing_template_decl)
3576 if (type_dependent_expression_p (arg1)
3577 || type_dependent_expression_p (arg2))
3578 return build_min_nt (ARRAY_REF, arg1, arg2,
3579 NULL_TREE, NULL_TREE);
3580 arg1 = build_non_dependent_expr (arg1);
3581 arg2 = build_non_dependent_expr (arg2);
3584 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3585 /*overload=*/NULL, complain);
3587 if (processing_template_decl && expr != error_mark_node)
3588 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3589 NULL_TREE, NULL_TREE);
3593 /* For the c-common bits. */
3595 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3596 int convert_p ATTRIBUTE_UNUSED)
3598 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3602 /* Build a binary-operation expression without default conversions.
3603 CODE is the kind of expression to build.
3604 LOCATION is the location_t of the operator in the source code.
3605 This function differs from `build' in several ways:
3606 the data type of the result is computed and recorded in it,
3607 warnings are generated if arg data types are invalid,
3608 special handling for addition and subtraction of pointers is known,
3609 and some optimization is done (operations on narrow ints
3610 are done in the narrower type when that gives the same result).
3611 Constant folding is also done before the result is returned.
3613 Note that the operands will never have enumeral types
3614 because either they have just had the default conversions performed
3615 or they have both just been converted to some other type in which
3616 the arithmetic is to be done.
3618 C++: must do special pointer arithmetic when implementing
3619 multiple inheritance, and deal with pointer to member functions. */
3622 cp_build_binary_op (location_t location,
3623 enum tree_code code, tree orig_op0, tree orig_op1,
3624 tsubst_flags_t complain)
3627 enum tree_code code0, code1;
3629 const char *invalid_op_diag;
3631 /* Expression code to give to the expression when it is built.
3632 Normally this is CODE, which is what the caller asked for,
3633 but in some special cases we change it. */
3634 enum tree_code resultcode = code;
3636 /* Data type in which the computation is to be performed.
3637 In the simplest cases this is the common type of the arguments. */
3638 tree result_type = NULL;
3640 /* Nonzero means operands have already been type-converted
3641 in whatever way is necessary.
3642 Zero means they need to be converted to RESULT_TYPE. */
3645 /* Nonzero means create the expression with this type, rather than
3647 tree build_type = 0;
3649 /* Nonzero means after finally constructing the expression
3650 convert it to this type. */
3651 tree final_type = 0;
3655 /* Nonzero if this is an operation like MIN or MAX which can
3656 safely be computed in short if both args are promoted shorts.
3657 Also implies COMMON.
3658 -1 indicates a bitwise operation; this makes a difference
3659 in the exact conditions for when it is safe to do the operation
3660 in a narrower mode. */
3663 /* Nonzero if this is a comparison operation;
3664 if both args are promoted shorts, compare the original shorts.
3665 Also implies COMMON. */
3666 int short_compare = 0;
3668 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3671 /* True if both operands have arithmetic type. */
3672 bool arithmetic_types_p;
3674 /* Apply default conversions. */
3678 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3679 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3680 || code == TRUTH_XOR_EXPR)
3682 if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0)))
3683 op0 = decay_conversion (op0);
3684 if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1)))
3685 op1 = decay_conversion (op1);
3689 if (!really_overloaded_fn (op0) && !VOID_TYPE_P (TREE_TYPE (op0)))
3690 op0 = default_conversion (op0);
3691 if (!really_overloaded_fn (op1) && !VOID_TYPE_P (TREE_TYPE (op1)))
3692 op1 = default_conversion (op1);
3695 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3696 STRIP_TYPE_NOPS (op0);
3697 STRIP_TYPE_NOPS (op1);
3699 /* DTRT if one side is an overloaded function, but complain about it. */
3700 if (type_unknown_p (op0))
3702 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3703 if (t != error_mark_node)
3705 if (complain & tf_error)
3706 permerror (input_location, "assuming cast to type %qT from overloaded function",
3711 if (type_unknown_p (op1))
3713 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3714 if (t != error_mark_node)
3716 if (complain & tf_error)
3717 permerror (input_location, "assuming cast to type %qT from overloaded function",
3723 type0 = TREE_TYPE (op0);
3724 type1 = TREE_TYPE (op1);
3726 /* The expression codes of the data types of the arguments tell us
3727 whether the arguments are integers, floating, pointers, etc. */
3728 code0 = TREE_CODE (type0);
3729 code1 = TREE_CODE (type1);
3731 /* If an error was already reported for one of the arguments,
3732 avoid reporting another error. */
3733 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3734 return error_mark_node;
3736 if ((invalid_op_diag
3737 = targetm.invalid_binary_op (code, type0, type1)))
3739 error (invalid_op_diag);
3740 return error_mark_node;
3743 /* Issue warnings about peculiar, but valid, uses of NULL. */
3744 if ((orig_op0 == null_node || orig_op1 == null_node)
3745 /* It's reasonable to use pointer values as operands of &&
3746 and ||, so NULL is no exception. */
3747 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3748 && ( /* Both are NULL (or 0) and the operation was not a
3749 comparison or a pointer subtraction. */
3750 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3751 && code != EQ_EXPR && code != NE_EXPR && code != MINUS_EXPR)
3752 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3753 || (!null_ptr_cst_p (orig_op0)
3754 && !TYPE_PTR_P (type0) && !TYPE_PTR_TO_MEMBER_P (type0))
3755 || (!null_ptr_cst_p (orig_op1)
3756 && !TYPE_PTR_P (type1) && !TYPE_PTR_TO_MEMBER_P (type1)))
3757 && (complain & tf_warning))
3758 /* Some sort of arithmetic operation involving NULL was
3760 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3765 /* Subtraction of two similar pointers.
3766 We must subtract them as integers, then divide by object size. */
3767 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3768 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3770 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3771 /* In all other cases except pointer - int, the usual arithmetic
3773 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3778 /* The pointer - int case is just like pointer + int; fall
3781 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3782 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3786 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3787 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3788 if (processing_template_decl)
3790 result_type = TREE_TYPE (ptr_operand);
3793 return cp_pointer_int_sum (code,
3804 case TRUNC_DIV_EXPR:
3806 case FLOOR_DIV_EXPR:
3807 case ROUND_DIV_EXPR:
3808 case EXACT_DIV_EXPR:
3809 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3810 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3811 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3812 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3814 enum tree_code tcode0 = code0, tcode1 = code1;
3816 warn_for_div_by_zero (location, op1);
3818 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3819 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3820 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3821 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3823 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3824 resultcode = RDIV_EXPR;
3826 /* When dividing two signed integers, we have to promote to int.
3827 unless we divide by a constant != -1. Note that default
3828 conversion will have been performed on the operands at this
3829 point, so we have to dig out the original type to find out if
3831 shorten = ((TREE_CODE (op0) == NOP_EXPR
3832 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3833 || (TREE_CODE (op1) == INTEGER_CST
3834 && ! integer_all_onesp (op1)));
3843 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3844 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3845 && !VECTOR_FLOAT_TYPE_P (type0)
3846 && !VECTOR_FLOAT_TYPE_P (type1)))
3850 case TRUNC_MOD_EXPR:
3851 case FLOOR_MOD_EXPR:
3852 warn_for_div_by_zero (location, op1);
3854 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3855 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3856 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3858 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3860 /* Although it would be tempting to shorten always here, that loses
3861 on some targets, since the modulo instruction is undefined if the
3862 quotient can't be represented in the computation mode. We shorten
3863 only if unsigned or if dividing by something we know != -1. */
3864 shorten = ((TREE_CODE (op0) == NOP_EXPR
3865 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3866 || (TREE_CODE (op1) == INTEGER_CST
3867 && ! integer_all_onesp (op1)));
3872 case TRUTH_ANDIF_EXPR:
3873 case TRUTH_ORIF_EXPR:
3874 case TRUTH_AND_EXPR:
3876 result_type = boolean_type_node;
3879 /* Shift operations: result has same type as first operand;
3880 always convert second operand to int.
3881 Also set SHORT_SHIFT if shifting rightward. */
3884 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3886 result_type = type0;
3887 if (TREE_CODE (op1) == INTEGER_CST)
3889 if (tree_int_cst_lt (op1, integer_zero_node))
3891 if ((complain & tf_warning)
3892 && c_inhibit_evaluation_warnings == 0)
3893 warning (0, "right shift count is negative");
3897 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3898 && (complain & tf_warning)
3899 && c_inhibit_evaluation_warnings == 0)
3900 warning (0, "right shift count >= width of type");
3903 /* Convert the shift-count to an integer, regardless of
3904 size of value being shifted. */
3905 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3906 op1 = cp_convert (integer_type_node, op1);
3907 /* Avoid converting op1 to result_type later. */
3913 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3915 result_type = type0;
3916 if (TREE_CODE (op1) == INTEGER_CST)
3918 if (tree_int_cst_lt (op1, integer_zero_node))
3920 if ((complain & tf_warning)
3921 && c_inhibit_evaluation_warnings == 0)
3922 warning (0, "left shift count is negative");
3924 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3926 if ((complain & tf_warning)
3927 && c_inhibit_evaluation_warnings == 0)
3928 warning (0, "left shift count >= width of type");
3931 /* Convert the shift-count to an integer, regardless of
3932 size of value being shifted. */
3933 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3934 op1 = cp_convert (integer_type_node, op1);
3935 /* Avoid converting op1 to result_type later. */
3942 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3944 result_type = type0;
3945 if (TREE_CODE (op1) == INTEGER_CST)
3947 if (tree_int_cst_lt (op1, integer_zero_node))
3949 if (complain & tf_warning)
3950 warning (0, (code == LROTATE_EXPR)
3951 ? G_("left rotate count is negative")
3952 : G_("right rotate count is negative"));
3954 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3956 if (complain & tf_warning)
3957 warning (0, (code == LROTATE_EXPR)
3958 ? G_("left rotate count >= width of type")
3959 : G_("right rotate count >= width of type"));
3962 /* Convert the shift-count to an integer, regardless of
3963 size of value being shifted. */
3964 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3965 op1 = cp_convert (integer_type_node, op1);
3971 if ((complain & tf_warning)
3972 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3973 warning (OPT_Wfloat_equal,
3974 "comparing floating point with == or != is unsafe");
3975 if ((complain & tf_warning)
3976 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3977 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3978 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3980 build_type = boolean_type_node;
3981 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3982 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
3983 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3984 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
3986 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3987 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3988 result_type = composite_pointer_type (type0, type1, op0, op1,
3989 CPO_COMPARISON, complain);
3990 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3991 && null_ptr_cst_p (op1))
3993 if (TREE_CODE (op0) == ADDR_EXPR
3994 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3996 if (complain & tf_warning)
3997 warning (OPT_Waddress, "the address of %qD will never be NULL",
3998 TREE_OPERAND (op0, 0));
4000 result_type = type0;
4002 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
4003 && null_ptr_cst_p (op0))
4005 if (TREE_CODE (op1) == ADDR_EXPR
4006 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
4008 if (complain & tf_warning)
4009 warning (OPT_Waddress, "the address of %qD will never be NULL",
4010 TREE_OPERAND (op1, 0));
4012 result_type = type1;
4014 else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1))
4015 /* One of the operands must be of nullptr_t type. */
4016 result_type = TREE_TYPE (nullptr_node);
4017 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
4019 result_type = type0;
4020 if (complain & tf_error)
4021 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4023 return error_mark_node;
4025 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
4027 result_type = type1;
4028 if (complain & tf_error)
4029 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4031 return error_mark_node;
4033 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
4035 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
4036 == ptrmemfunc_vbit_in_delta)
4038 tree pfn0 = pfn_from_ptrmemfunc (op0);
4039 tree delta0 = delta_from_ptrmemfunc (op0);
4040 tree e1 = cp_build_binary_op (location,
4043 build_zero_cst (TREE_TYPE (pfn0)),
4045 tree e2 = cp_build_binary_op (location,
4050 e2 = cp_build_binary_op (location,
4051 EQ_EXPR, e2, integer_zero_node,
4053 op0 = cp_build_binary_op (location,
4054 TRUTH_ANDIF_EXPR, e1, e2,
4056 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
4060 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
4061 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
4063 result_type = TREE_TYPE (op0);
4065 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
4066 return cp_build_binary_op (location, code, op1, op0, complain);
4067 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
4070 /* E will be the final comparison. */
4072 /* E1 and E2 are for scratch. */
4080 type = composite_pointer_type (type0, type1, op0, op1,
4081 CPO_COMPARISON, complain);
4083 if (!same_type_p (TREE_TYPE (op0), type))
4084 op0 = cp_convert_and_check (type, op0);
4085 if (!same_type_p (TREE_TYPE (op1), type))
4086 op1 = cp_convert_and_check (type, op1);
4088 if (op0 == error_mark_node || op1 == error_mark_node)
4089 return error_mark_node;
4091 if (TREE_SIDE_EFFECTS (op0))
4092 op0 = save_expr (op0);
4093 if (TREE_SIDE_EFFECTS (op1))
4094 op1 = save_expr (op1);
4096 pfn0 = pfn_from_ptrmemfunc (op0);
4097 pfn1 = pfn_from_ptrmemfunc (op1);
4098 delta0 = delta_from_ptrmemfunc (op0);
4099 delta1 = delta_from_ptrmemfunc (op1);
4100 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
4101 == ptrmemfunc_vbit_in_delta)
4106 && ((op0.delta == op1.delta)
4107 || (!op0.pfn && op0.delta & 1 == 0
4108 && op1.delta & 1 == 0))
4110 The reason for the `!op0.pfn' bit is that a NULL
4111 pointer-to-member is any member with a zero PFN and
4112 LSB of the DELTA field is 0. */
4114 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
4118 e1 = cp_build_binary_op (location,
4119 EQ_EXPR, e1, integer_zero_node,
4121 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
4125 e2 = cp_build_binary_op (location,
4126 EQ_EXPR, e2, integer_zero_node,
4128 e1 = cp_build_binary_op (location,
4129 TRUTH_ANDIF_EXPR, e2, e1,
4131 e2 = cp_build_binary_op (location, EQ_EXPR,
4133 build_zero_cst (TREE_TYPE (pfn0)),
4135 e2 = cp_build_binary_op (location,
4136 TRUTH_ANDIF_EXPR, e2, e1, complain);
4137 e1 = cp_build_binary_op (location,
4138 EQ_EXPR, delta0, delta1, complain);
4139 e1 = cp_build_binary_op (location,
4140 TRUTH_ORIF_EXPR, e1, e2, complain);
4147 && (!op0.pfn || op0.delta == op1.delta))
4149 The reason for the `!op0.pfn' bit is that a NULL
4150 pointer-to-member is any member with a zero PFN; the
4151 DELTA field is unspecified. */
4153 e1 = cp_build_binary_op (location,
4154 EQ_EXPR, delta0, delta1, complain);
4155 e2 = cp_build_binary_op (location,
4158 build_zero_cst (TREE_TYPE (pfn0)),
4160 e1 = cp_build_binary_op (location,
4161 TRUTH_ORIF_EXPR, e1, e2, complain);
4163 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
4164 e = cp_build_binary_op (location,
4165 TRUTH_ANDIF_EXPR, e2, e1, complain);
4166 if (code == EQ_EXPR)
4168 return cp_build_binary_op (location,
4169 EQ_EXPR, e, integer_zero_node, complain);
4173 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
4174 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
4176 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
4177 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
4185 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
4186 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
4188 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4189 result_type = composite_pointer_type (type0, type1, op0, op1,
4190 CPO_COMPARISON, complain);
4197 if (TREE_CODE (orig_op0) == STRING_CST
4198 || TREE_CODE (orig_op1) == STRING_CST)
4200 if (complain & tf_warning)
4201 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
4204 build_type = boolean_type_node;
4205 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
4206 || code0 == ENUMERAL_TYPE)
4207 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4208 || code1 == ENUMERAL_TYPE))
4210 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4211 result_type = composite_pointer_type (type0, type1, op0, op1,
4212 CPO_COMPARISON, complain);
4213 else if (code0 == POINTER_TYPE && null_ptr_cst_p (op1))
4215 result_type = type0;
4216 if (extra_warnings && (complain & tf_warning))
4217 warning (OPT_Wextra,
4218 "ordered comparison of pointer with integer zero");
4220 else if (code1 == POINTER_TYPE && null_ptr_cst_p (op0))
4222 result_type = type1;
4223 if (extra_warnings && (complain & tf_warning))
4224 warning (OPT_Wextra,
4225 "ordered comparison of pointer with integer zero");
4227 else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1))
4228 /* One of the operands must be of nullptr_t type. */
4229 result_type = TREE_TYPE (nullptr_node);
4230 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
4232 result_type = type0;
4233 if (complain & tf_error)
4234 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4236 return error_mark_node;
4238 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
4240 result_type = type1;
4241 if (complain & tf_error)
4242 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4244 return error_mark_node;
4248 case UNORDERED_EXPR:
4255 build_type = integer_type_node;
4256 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
4258 if (complain & tf_error)
4259 error ("unordered comparison on non-floating point argument");
4260 return error_mark_node;
4269 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
4270 || code0 == ENUMERAL_TYPE)
4271 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4272 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
4273 arithmetic_types_p = 1;
4276 arithmetic_types_p = 0;
4277 /* Vector arithmetic is only allowed when both sides are vectors. */
4278 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
4280 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
4281 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
4284 binary_op_error (location, code, type0, type1);
4285 return error_mark_node;
4287 arithmetic_types_p = 1;
4290 /* Determine the RESULT_TYPE, if it is not already known. */
4292 && arithmetic_types_p
4293 && (shorten || common || short_compare))
4295 result_type = cp_common_type (type0, type1);
4296 do_warn_double_promotion (result_type, type0, type1,
4297 "implicit conversion from %qT to %qT "
4298 "to match other operand of binary "
4305 if (complain & tf_error)
4306 error ("invalid operands of types %qT and %qT to binary %qO",
4307 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
4308 return error_mark_node;
4311 /* If we're in a template, the only thing we need to know is the
4313 if (processing_template_decl)
4315 /* Since the middle-end checks the type when doing a build2, we
4316 need to build the tree in pieces. This built tree will never
4317 get out of the front-end as we replace it when instantiating
4319 tree tmp = build2 (resultcode,
4320 build_type ? build_type : result_type,
4322 TREE_OPERAND (tmp, 0) = op0;
4326 if (arithmetic_types_p)
4328 bool first_complex = (code0 == COMPLEX_TYPE);
4329 bool second_complex = (code1 == COMPLEX_TYPE);
4330 int none_complex = (!first_complex && !second_complex);
4332 /* Adapted from patch for c/24581. */
4333 if (first_complex != second_complex
4334 && (code == PLUS_EXPR
4335 || code == MINUS_EXPR
4336 || code == MULT_EXPR
4337 || (code == TRUNC_DIV_EXPR && first_complex))
4338 && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE
4339 && flag_signed_zeros)
4341 /* An operation on mixed real/complex operands must be
4342 handled specially, but the language-independent code can
4343 more easily optimize the plain complex arithmetic if
4344 -fno-signed-zeros. */
4345 tree real_type = TREE_TYPE (result_type);
4349 if (TREE_TYPE (op0) != result_type)
4350 op0 = cp_convert_and_check (result_type, op0);
4351 if (TREE_TYPE (op1) != real_type)
4352 op1 = cp_convert_and_check (real_type, op1);
4356 if (TREE_TYPE (op0) != real_type)
4357 op0 = cp_convert_and_check (real_type, op0);
4358 if (TREE_TYPE (op1) != result_type)
4359 op1 = cp_convert_and_check (result_type, op1);
4361 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
4362 return error_mark_node;
4365 op0 = save_expr (op0);
4366 real = cp_build_unary_op (REALPART_EXPR, op0, 1, complain);
4367 imag = cp_build_unary_op (IMAGPART_EXPR, op0, 1, complain);
4371 case TRUNC_DIV_EXPR:
4372 op1 = save_expr (op1);
4373 imag = build2 (resultcode, real_type, imag, op1);
4377 real = build2 (resultcode, real_type, real, op1);
4385 op1 = save_expr (op1);
4386 real = cp_build_unary_op (REALPART_EXPR, op1, 1, complain);
4387 imag = cp_build_unary_op (IMAGPART_EXPR, op1, 1, complain);
4391 op0 = save_expr (op0);
4392 imag = build2 (resultcode, real_type, op0, imag);
4395 real = build2 (resultcode, real_type, op0, real);
4398 real = build2 (resultcode, real_type, op0, real);
4399 imag = build1 (NEGATE_EXPR, real_type, imag);
4405 real = fold_if_not_in_template (real);
4406 imag = fold_if_not_in_template (imag);
4407 result = build2 (COMPLEX_EXPR, result_type, real, imag);
4408 result = fold_if_not_in_template (result);
4412 /* For certain operations (which identify themselves by shorten != 0)
4413 if both args were extended from the same smaller type,
4414 do the arithmetic in that type and then extend.
4416 shorten !=0 and !=1 indicates a bitwise operation.
4417 For them, this optimization is safe only if
4418 both args are zero-extended or both are sign-extended.
4419 Otherwise, we might change the result.
4420 E.g., (short)-1 | (unsigned short)-1 is (int)-1
4421 but calculated in (unsigned short) it would be (unsigned short)-1. */
4423 if (shorten && none_complex)
4425 final_type = result_type;
4426 result_type = shorten_binary_op (result_type, op0, op1,
4430 /* Comparison operations are shortened too but differently.
4431 They identify themselves by setting short_compare = 1. */
4435 /* Don't write &op0, etc., because that would prevent op0
4436 from being kept in a register.
4437 Instead, make copies of the our local variables and
4438 pass the copies by reference, then copy them back afterward. */
4439 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4440 enum tree_code xresultcode = resultcode;
4442 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4444 return cp_convert (boolean_type_node, val);
4445 op0 = xop0, op1 = xop1;
4447 resultcode = xresultcode;
4450 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4451 && warn_sign_compare
4452 && !TREE_NO_WARNING (orig_op0)
4453 && !TREE_NO_WARNING (orig_op1)
4454 /* Do not warn until the template is instantiated; we cannot
4455 bound the ranges of the arguments until that point. */
4456 && !processing_template_decl
4457 && (complain & tf_warning)
4458 && c_inhibit_evaluation_warnings == 0)
4460 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4461 result_type, resultcode);
4465 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4466 Then the expression will be built.
4467 It will be given type FINAL_TYPE if that is nonzero;
4468 otherwise, it will be given type RESULT_TYPE. */
4471 if (TREE_TYPE (op0) != result_type)
4472 op0 = cp_convert_and_check (result_type, op0);
4473 if (TREE_TYPE (op1) != result_type)
4474 op1 = cp_convert_and_check (result_type, op1);
4476 if (op0 == error_mark_node || op1 == error_mark_node)
4477 return error_mark_node;
4480 if (build_type == NULL_TREE)
4481 build_type = result_type;
4483 result = build2 (resultcode, build_type, op0, op1);
4484 result = fold_if_not_in_template (result);
4485 if (final_type != 0)
4486 result = cp_convert (final_type, result);
4488 if (TREE_OVERFLOW_P (result)
4489 && !TREE_OVERFLOW_P (op0)
4490 && !TREE_OVERFLOW_P (op1))
4491 overflow_warning (location, result);
4496 /* Return a tree for the sum or difference (RESULTCODE says which)
4497 of pointer PTROP and integer INTOP. */
4500 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4502 tree res_type = TREE_TYPE (ptrop);
4504 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4505 in certain circumstance (when it's valid to do so). So we need
4506 to make sure it's complete. We don't need to check here, if we
4507 can actually complete it at all, as those checks will be done in
4508 pointer_int_sum() anyway. */
4509 complete_type (TREE_TYPE (res_type));
4511 return pointer_int_sum (input_location, resultcode, ptrop,
4512 fold_if_not_in_template (intop));
4515 /* Return a tree for the difference of pointers OP0 and OP1.
4516 The resulting tree has type int. */
4519 pointer_diff (tree op0, tree op1, tree ptrtype)
4522 tree restype = ptrdiff_type_node;
4523 tree target_type = TREE_TYPE (ptrtype);
4525 if (!complete_type_or_else (target_type, NULL_TREE))
4526 return error_mark_node;
4528 if (TREE_CODE (target_type) == VOID_TYPE)
4529 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4530 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4531 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4532 if (TREE_CODE (target_type) == METHOD_TYPE)
4533 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4535 /* First do the subtraction as integers;
4536 then drop through to build the divide operator. */
4538 op0 = cp_build_binary_op (input_location,
4540 cp_convert (restype, op0),
4541 cp_convert (restype, op1),
4542 tf_warning_or_error);
4544 /* This generates an error if op1 is a pointer to an incomplete type. */
4545 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4546 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4548 op1 = (TYPE_PTROB_P (ptrtype)
4549 ? size_in_bytes (target_type)
4550 : integer_one_node);
4552 /* Do the division. */
4554 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4555 return fold_if_not_in_template (result);
4558 /* Construct and perhaps optimize a tree representation
4559 for a unary operation. CODE, a tree_code, specifies the operation
4560 and XARG is the operand. */
4563 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4565 tree orig_expr = xarg;
4569 if (processing_template_decl)
4571 if (type_dependent_expression_p (xarg))
4572 return build_min_nt (code, xarg, NULL_TREE);
4574 xarg = build_non_dependent_expr (xarg);
4579 /* [expr.unary.op] says:
4581 The address of an object of incomplete type can be taken.
4583 (And is just the ordinary address operator, not an overloaded
4584 "operator &".) However, if the type is a template
4585 specialization, we must complete the type at this point so that
4586 an overloaded "operator &" will be available if required. */
4587 if (code == ADDR_EXPR
4588 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4589 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4590 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4591 || (TREE_CODE (xarg) == OFFSET_REF)))
4592 /* Don't look for a function. */;
4594 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4595 /*overload=*/NULL, complain);
4596 if (!exp && code == ADDR_EXPR)
4598 if (is_overloaded_fn (xarg))
4600 tree fn = get_first_fn (xarg);
4601 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4603 error (DECL_CONSTRUCTOR_P (fn)
4604 ? G_("taking address of constructor %qE")
4605 : G_("taking address of destructor %qE"),
4607 return error_mark_node;
4611 /* A pointer to member-function can be formed only by saying
4613 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4614 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4616 if (TREE_CODE (xarg) != OFFSET_REF
4617 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4619 error ("invalid use of %qE to form a pointer-to-member-function",
4621 if (TREE_CODE (xarg) != OFFSET_REF)
4622 inform (input_location, " a qualified-id is required");
4623 return error_mark_node;
4627 error ("parentheses around %qE cannot be used to form a"
4628 " pointer-to-member-function",
4630 PTRMEM_OK_P (xarg) = 1;
4634 if (TREE_CODE (xarg) == OFFSET_REF)
4636 ptrmem = PTRMEM_OK_P (xarg);
4638 if (!ptrmem && !flag_ms_extensions
4639 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4641 /* A single non-static member, make sure we don't allow a
4642 pointer-to-member. */
4643 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4644 TREE_OPERAND (xarg, 0),
4645 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4646 PTRMEM_OK_P (xarg) = ptrmem;
4650 exp = cp_build_addr_expr_strict (xarg, complain);
4653 if (processing_template_decl && exp != error_mark_node)
4654 exp = build_min_non_dep (code, exp, orig_expr,
4655 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4656 if (TREE_CODE (exp) == ADDR_EXPR)
4657 PTRMEM_OK_P (exp) = ptrmem;
4661 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4662 constants, where a null value is represented by an INTEGER_CST of
4666 cp_truthvalue_conversion (tree expr)
4668 tree type = TREE_TYPE (expr);
4669 if (TYPE_PTRMEM_P (type))
4670 return build_binary_op (EXPR_LOCATION (expr),
4671 NE_EXPR, expr, integer_zero_node, 1);
4673 return c_common_truthvalue_conversion (input_location, expr);
4676 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4679 condition_conversion (tree expr)
4682 if (processing_template_decl)
4684 t = perform_implicit_conversion_flags (boolean_type_node, expr,
4685 tf_warning_or_error, LOOKUP_NORMAL);
4686 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4690 /* Returns the address of T. This function will fold away
4691 ADDR_EXPR of INDIRECT_REF. */
4694 build_address (tree t)
4696 if (error_operand_p (t) || !cxx_mark_addressable (t))
4697 return error_mark_node;
4698 t = build_fold_addr_expr (t);
4699 if (TREE_CODE (t) != ADDR_EXPR)
4704 /* Returns the address of T with type TYPE. */
4707 build_typed_address (tree t, tree type)
4709 if (error_operand_p (t) || !cxx_mark_addressable (t))
4710 return error_mark_node;
4711 t = build_fold_addr_expr_with_type (t, type);
4712 if (TREE_CODE (t) != ADDR_EXPR)
4717 /* Return a NOP_EXPR converting EXPR to TYPE. */
4720 build_nop (tree type, tree expr)
4722 if (type == error_mark_node || error_operand_p (expr))
4724 return build1 (NOP_EXPR, type, expr);
4727 /* Take the address of ARG, whatever that means under C++ semantics.
4728 If STRICT_LVALUE is true, require an lvalue; otherwise, allow xvalues
4729 and class rvalues as well.
4731 Nothing should call this function directly; instead, callers should use
4732 cp_build_addr_expr or cp_build_addr_expr_strict. */
4735 cp_build_addr_expr_1 (tree arg, bool strict_lvalue, tsubst_flags_t complain)
4740 if (!arg || error_operand_p (arg))
4741 return error_mark_node;
4743 arg = mark_lvalue_use (arg);
4744 argtype = lvalue_type (arg);
4746 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4747 || !IDENTIFIER_OPNAME_P (arg));
4749 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4750 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4752 /* They're trying to take the address of a unique non-static
4753 member function. This is ill-formed (except in MS-land),
4754 but let's try to DTRT.
4755 Note: We only handle unique functions here because we don't
4756 want to complain if there's a static overload; non-unique
4757 cases will be handled by instantiate_type. But we need to
4758 handle this case here to allow casts on the resulting PMF.
4759 We could defer this in non-MS mode, but it's easier to give
4760 a useful error here. */
4762 /* Inside constant member functions, the `this' pointer
4763 contains an extra const qualifier. TYPE_MAIN_VARIANT
4764 is used here to remove this const from the diagnostics
4765 and the created OFFSET_REF. */
4766 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4767 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4770 if (! flag_ms_extensions)
4772 tree name = DECL_NAME (fn);
4773 if (!(complain & tf_error))
4774 return error_mark_node;
4775 else if (current_class_type
4776 && TREE_OPERAND (arg, 0) == current_class_ref)
4777 /* An expression like &memfn. */
4778 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4779 " or parenthesized non-static member function to form"
4780 " a pointer to member function. Say %<&%T::%D%>",
4783 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4784 " function to form a pointer to member function."
4788 arg = build_offset_ref (base, fn, /*address_p=*/true);
4791 /* Uninstantiated types are all functions. Taking the
4792 address of a function is a no-op, so just return the
4794 if (type_unknown_p (arg))
4795 return build1 (ADDR_EXPR, unknown_type_node, arg);
4797 if (TREE_CODE (arg) == OFFSET_REF)
4798 /* We want a pointer to member; bypass all the code for actually taking
4799 the address of something. */
4802 /* Anything not already handled and not a true memory reference
4804 if (TREE_CODE (argtype) != FUNCTION_TYPE
4805 && TREE_CODE (argtype) != METHOD_TYPE)
4807 cp_lvalue_kind kind = lvalue_kind (arg);
4808 if (kind == clk_none)
4810 if (complain & tf_error)
4811 lvalue_error (input_location, lv_addressof);
4812 return error_mark_node;
4814 if (strict_lvalue && (kind & (clk_rvalueref|clk_class)))
4816 if (!(complain & tf_error))
4817 return error_mark_node;
4818 if (kind & clk_class)
4819 /* Make this a permerror because we used to accept it. */
4820 permerror (input_location, "taking address of temporary");
4822 error ("taking address of xvalue (rvalue reference)");
4826 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4828 tree type = build_pointer_type (TREE_TYPE (argtype));
4829 arg = build1 (CONVERT_EXPR, type, arg);
4832 else if (pedantic && DECL_MAIN_P (arg))
4835 /* Apparently a lot of autoconf scripts for C++ packages do this,
4836 so only complain if -pedantic. */
4837 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4838 pedwarn (input_location, OPT_pedantic,
4839 "ISO C++ forbids taking address of function %<::main%>");
4840 else if (flag_pedantic_errors)
4841 return error_mark_node;
4844 /* Let &* cancel out to simplify resulting code. */
4845 if (TREE_CODE (arg) == INDIRECT_REF)
4847 /* We don't need to have `current_class_ptr' wrapped in a
4848 NON_LVALUE_EXPR node. */
4849 if (arg == current_class_ref)
4850 return current_class_ptr;
4852 arg = TREE_OPERAND (arg, 0);
4853 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4855 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4856 arg = build1 (CONVERT_EXPR, type, arg);
4859 /* Don't let this be an lvalue. */
4864 /* ??? Cope with user tricks that amount to offsetof. */
4865 if (TREE_CODE (argtype) != FUNCTION_TYPE
4866 && TREE_CODE (argtype) != METHOD_TYPE
4867 && argtype != unknown_type_node
4868 && (val = get_base_address (arg))
4869 && COMPLETE_TYPE_P (TREE_TYPE (val))
4870 && TREE_CODE (val) == INDIRECT_REF
4871 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
4873 tree type = build_pointer_type (argtype);
4874 tree op0 = fold_convert (type, TREE_OPERAND (val, 0));
4875 tree op1 = fold_offsetof (arg, val);
4876 return fold_build_pointer_plus (op0, op1);
4879 /* Handle complex lvalues (when permitted)
4880 by reduction to simpler cases. */
4881 val = unary_complex_lvalue (ADDR_EXPR, arg);
4885 switch (TREE_CODE (arg))
4889 case FIX_TRUNC_EXPR:
4890 /* Even if we're not being pedantic, we cannot allow this
4891 extension when we're instantiating in a SFINAE
4893 if (! lvalue_p (arg) && complain == tf_none)
4895 if (complain & tf_error)
4896 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4898 return error_mark_node;
4903 arg = BASELINK_FUNCTIONS (arg);
4907 arg = OVL_CURRENT (arg);
4912 /* Turn a reference to a non-static data member into a
4913 pointer-to-member. */
4918 gcc_assert (PTRMEM_OK_P (arg));
4920 t = TREE_OPERAND (arg, 1);
4921 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4923 if (complain & tf_error)
4924 error ("cannot create pointer to reference member %qD", t);
4925 return error_mark_node;
4928 type = build_ptrmem_type (context_for_name_lookup (t),
4930 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4938 if (argtype != error_mark_node)
4939 argtype = build_pointer_type (argtype);
4941 /* In a template, we are processing a non-dependent expression
4942 so we can just form an ADDR_EXPR with the correct type. */
4943 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4945 val = build_address (arg);
4946 if (TREE_CODE (arg) == OFFSET_REF)
4947 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4949 else if (BASELINK_P (TREE_OPERAND (arg, 1)))
4951 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4953 /* We can only get here with a single static member
4955 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4956 && DECL_STATIC_FUNCTION_P (fn));
4958 val = build_address (fn);
4959 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4960 /* Do not lose object's side effects. */
4961 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4962 TREE_OPERAND (arg, 0), val);
4964 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4966 if (complain & tf_error)
4967 error ("attempt to take address of bit-field structure member %qD",
4968 TREE_OPERAND (arg, 1));
4969 return error_mark_node;
4973 tree object = TREE_OPERAND (arg, 0);
4974 tree field = TREE_OPERAND (arg, 1);
4975 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4976 (TREE_TYPE (object), decl_type_context (field)));
4977 val = build_address (arg);
4980 if (TREE_CODE (argtype) == POINTER_TYPE
4981 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4983 build_ptrmemfunc_type (argtype);
4984 val = build_ptrmemfunc (argtype, val, 0,
4986 tf_warning_or_error);
4992 /* Take the address of ARG if it has one, even if it's an rvalue. */
4995 cp_build_addr_expr (tree arg, tsubst_flags_t complain)
4997 return cp_build_addr_expr_1 (arg, 0, complain);
5000 /* Take the address of ARG, but only if it's an lvalue. */
5003 cp_build_addr_expr_strict (tree arg, tsubst_flags_t complain)
5005 return cp_build_addr_expr_1 (arg, 1, complain);
5008 /* C++: Must handle pointers to members.
5010 Perhaps type instantiation should be extended to handle conversion
5011 from aggregates to types we don't yet know we want? (Or are those
5012 cases typically errors which should be reported?)
5014 NOCONVERT nonzero suppresses the default promotions
5015 (such as from short to int). */
5018 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
5019 tsubst_flags_t complain)
5021 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
5024 const char *errstring = NULL;
5026 const char *invalid_op_diag;
5028 if (!arg || error_operand_p (arg))
5029 return error_mark_node;
5031 if ((invalid_op_diag
5032 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
5037 error (invalid_op_diag);
5038 return error_mark_node;
5043 case UNARY_PLUS_EXPR:
5046 int flags = WANT_ARITH | WANT_ENUM;
5047 /* Unary plus (but not unary minus) is allowed on pointers. */
5048 if (code == UNARY_PLUS_EXPR)
5049 flags |= WANT_POINTER;
5050 arg = build_expr_type_conversion (flags, arg, true);
5052 errstring = (code == NEGATE_EXPR
5053 ? _("wrong type argument to unary minus")
5054 : _("wrong type argument to unary plus"));
5057 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
5058 arg = perform_integral_promotions (arg);
5060 /* Make sure the result is not an lvalue: a unary plus or minus
5061 expression is always a rvalue. */
5068 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
5072 arg = default_conversion (arg);
5074 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
5075 | WANT_VECTOR_OR_COMPLEX,
5077 errstring = _("wrong type argument to bit-complement");
5078 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
5079 arg = perform_integral_promotions (arg);
5083 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
5084 errstring = _("wrong type argument to abs");
5085 else if (!noconvert)
5086 arg = default_conversion (arg);
5090 /* Conjugating a real value is a no-op, but allow it anyway. */
5091 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
5092 errstring = _("wrong type argument to conjugation");
5093 else if (!noconvert)
5094 arg = default_conversion (arg);
5097 case TRUTH_NOT_EXPR:
5098 arg = perform_implicit_conversion (boolean_type_node, arg,
5100 val = invert_truthvalue_loc (input_location, arg);
5101 if (arg != error_mark_node)
5103 errstring = _("in argument to unary !");
5111 arg = build_real_imag_expr (input_location, code, arg);
5112 if (arg == error_mark_node)
5115 return fold_if_not_in_template (arg);
5117 case PREINCREMENT_EXPR:
5118 case POSTINCREMENT_EXPR:
5119 case PREDECREMENT_EXPR:
5120 case POSTDECREMENT_EXPR:
5121 /* Handle complex lvalues (when permitted)
5122 by reduction to simpler cases. */
5124 val = unary_complex_lvalue (code, arg);
5128 arg = mark_lvalue_use (arg);
5130 /* Increment or decrement the real part of the value,
5131 and don't change the imaginary part. */
5132 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
5136 arg = stabilize_reference (arg);
5137 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
5138 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
5139 real = cp_build_unary_op (code, real, 1, complain);
5140 if (real == error_mark_node || imag == error_mark_node)
5141 return error_mark_node;
5142 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
5146 /* Report invalid types. */
5148 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
5151 if (code == PREINCREMENT_EXPR)
5152 errstring = _("no pre-increment operator for type");
5153 else if (code == POSTINCREMENT_EXPR)
5154 errstring = _("no post-increment operator for type");
5155 else if (code == PREDECREMENT_EXPR)
5156 errstring = _("no pre-decrement operator for type");
5158 errstring = _("no post-decrement operator for type");
5161 else if (arg == error_mark_node)
5162 return error_mark_node;
5164 /* Report something read-only. */
5166 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
5167 || TREE_READONLY (arg))
5169 if (complain & tf_error)
5170 cxx_readonly_error (arg, ((code == PREINCREMENT_EXPR
5171 || code == POSTINCREMENT_EXPR)
5172 ? lv_increment : lv_decrement));
5174 return error_mark_node;
5179 tree declared_type = unlowered_expr_type (arg);
5181 argtype = TREE_TYPE (arg);
5183 /* ARM $5.2.5 last annotation says this should be forbidden. */
5184 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
5186 if (complain & tf_error)
5187 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
5188 ? G_("ISO C++ forbids incrementing an enum")
5189 : G_("ISO C++ forbids decrementing an enum"));
5191 return error_mark_node;
5194 /* Compute the increment. */
5196 if (TREE_CODE (argtype) == POINTER_TYPE)
5198 tree type = complete_type (TREE_TYPE (argtype));
5200 if (!COMPLETE_OR_VOID_TYPE_P (type))
5202 if (complain & tf_error)
5203 error (((code == PREINCREMENT_EXPR
5204 || code == POSTINCREMENT_EXPR))
5205 ? G_("cannot increment a pointer to incomplete type %qT")
5206 : G_("cannot decrement a pointer to incomplete type %qT"),
5207 TREE_TYPE (argtype));
5209 return error_mark_node;
5211 else if ((pedantic || warn_pointer_arith)
5212 && !TYPE_PTROB_P (argtype))
5214 if (complain & tf_error)
5215 permerror (input_location, (code == PREINCREMENT_EXPR
5216 || code == POSTINCREMENT_EXPR)
5217 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
5218 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
5221 return error_mark_node;
5224 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
5227 inc = integer_one_node;
5229 inc = cp_convert (argtype, inc);
5231 /* If 'arg' is an Objective-C PROPERTY_REF expression, then we
5232 need to ask Objective-C to build the increment or decrement
5233 expression for it. */
5234 if (objc_is_property_ref (arg))
5235 return objc_build_incr_expr_for_property_ref (input_location, code,
5238 /* Complain about anything else that is not a true lvalue. */
5239 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
5240 || code == POSTINCREMENT_EXPR)
5241 ? lv_increment : lv_decrement),
5243 return error_mark_node;
5245 /* Forbid using -- on `bool'. */
5246 if (TREE_CODE (declared_type) == BOOLEAN_TYPE)
5248 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
5250 if (complain & tf_error)
5251 error ("invalid use of Boolean expression as operand "
5252 "to %<operator--%>");
5253 return error_mark_node;
5255 val = boolean_increment (code, arg);
5257 else if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
5258 /* An rvalue has no cv-qualifiers. */
5259 val = build2 (code, cv_unqualified (TREE_TYPE (arg)), arg, inc);
5261 val = build2 (code, TREE_TYPE (arg), arg, inc);
5263 TREE_SIDE_EFFECTS (val) = 1;
5268 /* Note that this operation never does default_conversion
5269 regardless of NOCONVERT. */
5270 return cp_build_addr_expr (arg, complain);
5279 argtype = TREE_TYPE (arg);
5280 return fold_if_not_in_template (build1 (code, argtype, arg));
5283 if (complain & tf_error)
5284 error ("%s", errstring);
5285 return error_mark_node;
5288 /* Hook for the c-common bits that build a unary op. */
5290 build_unary_op (location_t location ATTRIBUTE_UNUSED,
5291 enum tree_code code, tree xarg, int noconvert)
5293 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
5296 /* Apply unary lvalue-demanding operator CODE to the expression ARG
5297 for certain kinds of expressions which are not really lvalues
5298 but which we can accept as lvalues.
5300 If ARG is not a kind of expression we can handle, return
5304 unary_complex_lvalue (enum tree_code code, tree arg)
5306 /* Inside a template, making these kinds of adjustments is
5307 pointless; we are only concerned with the type of the
5309 if (processing_template_decl)
5312 /* Handle (a, b) used as an "lvalue". */
5313 if (TREE_CODE (arg) == COMPOUND_EXPR)
5315 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
5316 tf_warning_or_error);
5317 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5318 TREE_OPERAND (arg, 0), real_result);
5321 /* Handle (a ? b : c) used as an "lvalue". */
5322 if (TREE_CODE (arg) == COND_EXPR
5323 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
5324 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
5326 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
5327 if (TREE_CODE (arg) == MODIFY_EXPR
5328 || TREE_CODE (arg) == PREINCREMENT_EXPR
5329 || TREE_CODE (arg) == PREDECREMENT_EXPR)
5331 tree lvalue = TREE_OPERAND (arg, 0);
5332 if (TREE_SIDE_EFFECTS (lvalue))
5334 lvalue = stabilize_reference (lvalue);
5335 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
5336 lvalue, TREE_OPERAND (arg, 1));
5338 return unary_complex_lvalue
5339 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
5342 if (code != ADDR_EXPR)
5345 /* Handle (a = b) used as an "lvalue" for `&'. */
5346 if (TREE_CODE (arg) == MODIFY_EXPR
5347 || TREE_CODE (arg) == INIT_EXPR)
5349 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
5350 tf_warning_or_error);
5351 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5353 TREE_NO_WARNING (arg) = 1;
5357 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
5358 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
5359 || TREE_CODE (arg) == OFFSET_REF)
5362 /* We permit compiler to make function calls returning
5363 objects of aggregate type look like lvalues. */
5367 if (TREE_CODE (targ) == SAVE_EXPR)
5368 targ = TREE_OPERAND (targ, 0);
5370 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
5372 if (TREE_CODE (arg) == SAVE_EXPR)
5375 targ = build_cplus_new (TREE_TYPE (arg), arg, tf_warning_or_error);
5376 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
5379 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
5380 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
5381 TREE_OPERAND (targ, 0), current_function_decl, NULL);
5384 /* Don't let anything else be handled specially. */
5388 /* Mark EXP saying that we need to be able to take the
5389 address of it; it should not be allocated in a register.
5390 Value is true if successful.
5392 C++: we do not allow `current_class_ptr' to be addressable. */
5395 cxx_mark_addressable (tree exp)
5400 switch (TREE_CODE (x))
5407 x = TREE_OPERAND (x, 0);
5411 if (x == current_class_ptr)
5413 error ("cannot take the address of %<this%>, which is an rvalue expression");
5414 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
5420 /* Caller should not be trying to mark initialized
5421 constant fields addressable. */
5422 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
5423 || DECL_IN_AGGR_P (x) == 0
5425 || DECL_EXTERNAL (x));
5429 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
5430 && !DECL_ARTIFICIAL (x))
5432 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
5435 ("address of explicit register variable %qD requested", x);
5438 else if (extra_warnings)
5440 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
5442 TREE_ADDRESSABLE (x) = 1;
5447 TREE_ADDRESSABLE (x) = 1;
5451 TREE_ADDRESSABLE (x) = 1;
5455 TREE_ADDRESSABLE (x) = 1;
5456 cxx_mark_addressable (TREE_OPERAND (x, 0));
5464 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
5467 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
5468 tsubst_flags_t complain)
5470 tree orig_ifexp = ifexp;
5471 tree orig_op1 = op1;
5472 tree orig_op2 = op2;
5475 if (processing_template_decl)
5477 /* The standard says that the expression is type-dependent if
5478 IFEXP is type-dependent, even though the eventual type of the
5479 expression doesn't dependent on IFEXP. */
5480 if (type_dependent_expression_p (ifexp)
5481 /* As a GNU extension, the middle operand may be omitted. */
5482 || (op1 && type_dependent_expression_p (op1))
5483 || type_dependent_expression_p (op2))
5484 return build_min_nt (COND_EXPR, ifexp, op1, op2);
5485 ifexp = build_non_dependent_expr (ifexp);
5487 op1 = build_non_dependent_expr (op1);
5488 op2 = build_non_dependent_expr (op2);
5491 expr = build_conditional_expr (ifexp, op1, op2, complain);
5492 if (processing_template_decl && expr != error_mark_node)
5493 return build_min_non_dep (COND_EXPR, expr,
5494 orig_ifexp, orig_op1, orig_op2);
5498 /* Given a list of expressions, return a compound expression
5499 that performs them all and returns the value of the last of them. */
5502 build_x_compound_expr_from_list (tree list, expr_list_kind exp,
5503 tsubst_flags_t complain)
5505 tree expr = TREE_VALUE (list);
5507 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5508 && !CONSTRUCTOR_IS_DIRECT_INIT (expr))
5510 if (complain & tf_error)
5511 pedwarn (EXPR_LOC_OR_HERE (expr), 0, "list-initializer for "
5512 "non-class type must not be parenthesized");
5514 return error_mark_node;
5517 if (TREE_CHAIN (list))
5519 if (complain & tf_error)
5523 permerror (input_location, "expression list treated as compound "
5524 "expression in initializer");
5527 permerror (input_location, "expression list treated as compound "
5528 "expression in mem-initializer");
5531 permerror (input_location, "expression list treated as compound "
5532 "expression in functional cast");
5538 return error_mark_node;
5540 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5541 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5548 /* Like build_x_compound_expr_from_list, but using a VEC. */
5551 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5553 if (VEC_empty (tree, vec))
5555 else if (VEC_length (tree, vec) == 1)
5556 return VEC_index (tree, vec, 0);
5564 permerror (input_location,
5565 "%s expression list treated as compound expression",
5568 expr = VEC_index (tree, vec, 0);
5569 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5570 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5576 /* Handle overloading of the ',' operator when needed. */
5579 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5582 tree orig_op1 = op1;
5583 tree orig_op2 = op2;
5585 if (processing_template_decl)
5587 if (type_dependent_expression_p (op1)
5588 || type_dependent_expression_p (op2))
5589 return build_min_nt (COMPOUND_EXPR, op1, op2);
5590 op1 = build_non_dependent_expr (op1);
5591 op2 = build_non_dependent_expr (op2);
5594 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5595 /*overload=*/NULL, complain);
5597 result = cp_build_compound_expr (op1, op2, complain);
5599 if (processing_template_decl && result != error_mark_node)
5600 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5605 /* Like cp_build_compound_expr, but for the c-common bits. */
5608 build_compound_expr (location_t loc ATTRIBUTE_UNUSED, tree lhs, tree rhs)
5610 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5613 /* Build a compound expression. */
5616 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5618 lhs = convert_to_void (lhs, ICV_LEFT_OF_COMMA, complain);
5620 if (lhs == error_mark_node || rhs == error_mark_node)
5621 return error_mark_node;
5623 if (TREE_CODE (rhs) == TARGET_EXPR)
5625 /* If the rhs is a TARGET_EXPR, then build the compound
5626 expression inside the target_expr's initializer. This
5627 helps the compiler to eliminate unnecessary temporaries. */
5628 tree init = TREE_OPERAND (rhs, 1);
5630 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5631 TREE_OPERAND (rhs, 1) = init;
5636 if (type_unknown_p (rhs))
5638 error ("no context to resolve type of %qE", rhs);
5639 return error_mark_node;
5642 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5645 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5646 casts away constness. CAST gives the type of cast. Returns true
5647 if the cast is ill-formed, false if it is well-formed.
5649 ??? This function warns for casting away any qualifier not just
5650 const. We would like to specify exactly what qualifiers are casted
5655 check_for_casting_away_constness (tree src_type, tree dest_type,
5656 enum tree_code cast, tsubst_flags_t complain)
5658 /* C-style casts are allowed to cast away constness. With
5659 WARN_CAST_QUAL, we still want to issue a warning. */
5660 if (cast == CAST_EXPR && !warn_cast_qual)
5663 if (!casts_away_constness (src_type, dest_type))
5669 if (complain & tf_warning)
5670 warning (OPT_Wcast_qual,
5671 "cast from type %qT to type %qT casts away qualifiers",
5672 src_type, dest_type);
5675 case STATIC_CAST_EXPR:
5676 if (complain & tf_error)
5677 error ("static_cast from type %qT to type %qT casts away qualifiers",
5678 src_type, dest_type);
5681 case REINTERPRET_CAST_EXPR:
5682 if (complain & tf_error)
5683 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5684 src_type, dest_type);
5692 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5693 (another pointer-to-member type in the same hierarchy) and return
5694 the converted expression. If ALLOW_INVERSE_P is permitted, a
5695 pointer-to-derived may be converted to pointer-to-base; otherwise,
5696 only the other direction is permitted. If C_CAST_P is true, this
5697 conversion is taking place as part of a C-style cast. */
5700 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5701 bool c_cast_p, tsubst_flags_t complain)
5703 if (TYPE_PTRMEM_P (type))
5707 if (TREE_CODE (expr) == PTRMEM_CST)
5708 expr = cplus_expand_constant (expr);
5709 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5710 TYPE_PTRMEM_CLASS_TYPE (type),
5712 c_cast_p, complain);
5713 if (delta == error_mark_node)
5714 return error_mark_node;
5716 if (!integer_zerop (delta))
5718 tree cond, op1, op2;
5720 cond = cp_build_binary_op (input_location,
5723 build_int_cst (TREE_TYPE (expr), -1),
5724 tf_warning_or_error);
5725 op1 = build_nop (ptrdiff_type_node, expr);
5726 op2 = cp_build_binary_op (input_location,
5727 PLUS_EXPR, op1, delta,
5728 tf_warning_or_error);
5730 expr = fold_build3_loc (input_location,
5731 COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5735 return build_nop (type, expr);
5738 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5739 allow_inverse_p, c_cast_p, complain);
5742 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5743 this static_cast is being attempted as one of the possible casts
5744 allowed by a C-style cast. (In that case, accessibility of base
5745 classes is not considered, and it is OK to cast away
5746 constness.) Return the result of the cast. *VALID_P is set to
5747 indicate whether or not the cast was valid. */
5750 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5751 bool *valid_p, tsubst_flags_t complain)
5756 /* Assume the cast is valid. */
5759 intype = TREE_TYPE (expr);
5761 /* Save casted types in the function's used types hash table. */
5762 used_types_insert (type);
5764 /* [expr.static.cast]
5766 An lvalue of type "cv1 B", where B is a class type, can be cast
5767 to type "reference to cv2 D", where D is a class derived (clause
5768 _class.derived_) from B, if a valid standard conversion from
5769 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5770 same cv-qualification as, or greater cv-qualification than, cv1,
5771 and B is not a virtual base class of D. */
5772 /* We check this case before checking the validity of "TYPE t =
5773 EXPR;" below because for this case:
5776 struct D : public B { D(const B&); };
5778 void f() { static_cast<const D&>(b); }
5780 we want to avoid constructing a new D. The standard is not
5781 completely clear about this issue, but our interpretation is
5782 consistent with other compilers. */
5783 if (TREE_CODE (type) == REFERENCE_TYPE
5784 && CLASS_TYPE_P (TREE_TYPE (type))
5785 && CLASS_TYPE_P (intype)
5786 && (TYPE_REF_IS_RVALUE (type) || real_lvalue_p (expr))
5787 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5788 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5789 build_pointer_type (TYPE_MAIN_VARIANT
5790 (TREE_TYPE (type))))
5792 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5796 /* There is a standard conversion from "D*" to "B*" even if "B"
5797 is ambiguous or inaccessible. If this is really a
5798 static_cast, then we check both for inaccessibility and
5799 ambiguity. However, if this is a static_cast being performed
5800 because the user wrote a C-style cast, then accessibility is
5802 base = lookup_base (TREE_TYPE (type), intype,
5803 c_cast_p ? ba_unique : ba_check,
5806 /* Convert from "B*" to "D*". This function will check that "B"
5807 is not a virtual base of "D". */
5808 expr = build_base_path (MINUS_EXPR, build_address (expr),
5809 base, /*nonnull=*/false, complain);
5810 /* Convert the pointer to a reference -- but then remember that
5811 there are no expressions with reference type in C++.
5813 We call rvalue so that there's an actual tree code
5814 (NON_LVALUE_EXPR) for the static_cast; otherwise, if the operand
5815 is a variable with the same type, the conversion would get folded
5816 away, leaving just the variable and causing lvalue_kind to give
5817 the wrong answer. */
5818 return convert_from_reference (rvalue (cp_fold_convert (type, expr)));
5821 /* "A glvalue of type cv1 T1 can be cast to type rvalue reference to
5822 cv2 T2 if cv2 T2 is reference-compatible with cv1 T1 (8.5.3)." */
5823 if (TREE_CODE (type) == REFERENCE_TYPE
5824 && TYPE_REF_IS_RVALUE (type)
5825 && lvalue_or_rvalue_with_address_p (expr)
5826 && reference_related_p (TREE_TYPE (type), intype)
5827 && (c_cast_p || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5829 expr = build_typed_address (expr, type);
5830 return convert_from_reference (expr);
5833 /* Resolve overloaded address here rather than once in
5834 implicit_conversion and again in the inverse code below. */
5835 if (TYPE_PTRMEMFUNC_P (type) && type_unknown_p (expr))
5837 expr = instantiate_type (type, expr, complain);
5838 intype = TREE_TYPE (expr);
5841 /* [expr.static.cast]
5843 An expression e can be explicitly converted to a type T using a
5844 static_cast of the form static_cast<T>(e) if the declaration T
5845 t(e);" is well-formed, for some invented temporary variable
5847 result = perform_direct_initialization_if_possible (type, expr,
5848 c_cast_p, complain);
5851 result = convert_from_reference (result);
5853 /* [expr.static.cast]
5855 If T is a reference type, the result is an lvalue; otherwise,
5856 the result is an rvalue. */
5857 if (TREE_CODE (type) != REFERENCE_TYPE)
5858 result = rvalue (result);
5862 /* [expr.static.cast]
5864 Any expression can be explicitly converted to type cv void. */
5865 if (TREE_CODE (type) == VOID_TYPE)
5866 return convert_to_void (expr, ICV_CAST, complain);
5868 /* [expr.static.cast]
5870 The inverse of any standard conversion sequence (clause _conv_),
5871 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5872 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5873 (_conv.bool_) conversions, can be performed explicitly using
5874 static_cast subject to the restriction that the explicit
5875 conversion does not cast away constness (_expr.const.cast_), and
5876 the following additional rules for specific cases: */
5877 /* For reference, the conversions not excluded are: integral
5878 promotions, floating point promotion, integral conversions,
5879 floating point conversions, floating-integral conversions,
5880 pointer conversions, and pointer to member conversions. */
5883 A value of integral _or enumeration_ type can be explicitly
5884 converted to an enumeration type. */
5885 /* The effect of all that is that any conversion between any two
5886 types which are integral, floating, or enumeration types can be
5888 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5889 || SCALAR_FLOAT_TYPE_P (type))
5890 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5891 || SCALAR_FLOAT_TYPE_P (intype)))
5892 return ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5894 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5895 && CLASS_TYPE_P (TREE_TYPE (type))
5896 && CLASS_TYPE_P (TREE_TYPE (intype))
5897 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5898 (TREE_TYPE (intype))),
5899 build_pointer_type (TYPE_MAIN_VARIANT
5900 (TREE_TYPE (type)))))
5905 && check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR,
5907 return error_mark_node;
5908 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5909 c_cast_p ? ba_unique : ba_check,
5911 expr = build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false,
5913 return cp_fold_convert(type, expr);
5916 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5917 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5924 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5925 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5927 if (TYPE_PTRMEM_P (type))
5929 t1 = (build_ptrmem_type
5931 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5932 t2 = (build_ptrmem_type
5934 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5941 if (can_convert (t1, t2) || can_convert (t2, t1))
5944 && check_for_casting_away_constness (intype, type,
5947 return error_mark_node;
5948 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5949 c_cast_p, complain);
5953 /* [expr.static.cast]
5955 An rvalue of type "pointer to cv void" can be explicitly
5956 converted to a pointer to object type. A value of type pointer
5957 to object converted to "pointer to cv void" and back to the
5958 original pointer type will have its original value. */
5959 if (TREE_CODE (intype) == POINTER_TYPE
5960 && VOID_TYPE_P (TREE_TYPE (intype))
5961 && TYPE_PTROB_P (type))
5964 && check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR,
5966 return error_mark_node;
5967 return build_nop (type, expr);
5971 return error_mark_node;
5974 /* Return an expression representing static_cast<TYPE>(EXPR). */
5977 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5982 if (type == error_mark_node || expr == error_mark_node)
5983 return error_mark_node;
5985 if (processing_template_decl)
5987 expr = build_min (STATIC_CAST_EXPR, type, expr);
5988 /* We don't know if it will or will not have side effects. */
5989 TREE_SIDE_EFFECTS (expr) = 1;
5990 return convert_from_reference (expr);
5993 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5994 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5995 if (TREE_CODE (type) != REFERENCE_TYPE
5996 && TREE_CODE (expr) == NOP_EXPR
5997 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5998 expr = TREE_OPERAND (expr, 0);
6000 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
6005 if (complain & tf_error)
6006 error ("invalid static_cast from type %qT to type %qT",
6007 TREE_TYPE (expr), type);
6008 return error_mark_node;
6011 /* EXPR is an expression with member function or pointer-to-member
6012 function type. TYPE is a pointer type. Converting EXPR to TYPE is
6013 not permitted by ISO C++, but we accept it in some modes. If we
6014 are not in one of those modes, issue a diagnostic. Return the
6015 converted expression. */
6018 convert_member_func_to_ptr (tree type, tree expr)
6023 intype = TREE_TYPE (expr);
6024 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
6025 || TREE_CODE (intype) == METHOD_TYPE);
6027 if (pedantic || warn_pmf2ptr)
6028 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
6029 "converting from %qT to %qT", intype, type);
6031 if (TREE_CODE (intype) == METHOD_TYPE)
6032 expr = build_addr_func (expr);
6033 else if (TREE_CODE (expr) == PTRMEM_CST)
6034 expr = build_address (PTRMEM_CST_MEMBER (expr));
6037 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
6038 decl = build_address (decl);
6039 expr = get_member_function_from_ptrfunc (&decl, expr);
6042 return build_nop (type, expr);
6045 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
6046 If C_CAST_P is true, this reinterpret cast is being done as part of
6047 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
6048 indicate whether or not reinterpret_cast was valid. */
6051 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
6052 bool *valid_p, tsubst_flags_t complain)
6056 /* Assume the cast is invalid. */
6060 if (type == error_mark_node || error_operand_p (expr))
6061 return error_mark_node;
6063 intype = TREE_TYPE (expr);
6065 /* Save casted types in the function's used types hash table. */
6066 used_types_insert (type);
6068 /* [expr.reinterpret.cast]
6069 An lvalue expression of type T1 can be cast to the type
6070 "reference to T2" if an expression of type "pointer to T1" can be
6071 explicitly converted to the type "pointer to T2" using a
6072 reinterpret_cast. */
6073 if (TREE_CODE (type) == REFERENCE_TYPE)
6075 if (! real_lvalue_p (expr))
6077 if (complain & tf_error)
6078 error ("invalid cast of an rvalue expression of type "
6081 return error_mark_node;
6084 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
6085 "B" are related class types; the reinterpret_cast does not
6086 adjust the pointer. */
6087 if (TYPE_PTR_P (intype)
6088 && (complain & tf_warning)
6089 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
6090 COMPARE_BASE | COMPARE_DERIVED)))
6091 warning (0, "casting %qT to %qT does not dereference pointer",
6094 expr = cp_build_addr_expr (expr, complain);
6096 if (warn_strict_aliasing > 2)
6097 strict_aliasing_warning (TREE_TYPE (expr), type, expr);
6099 if (expr != error_mark_node)
6100 expr = build_reinterpret_cast_1
6101 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
6103 if (expr != error_mark_node)
6104 /* cp_build_indirect_ref isn't right for rvalue refs. */
6105 expr = convert_from_reference (fold_convert (type, expr));
6109 /* As a G++ extension, we consider conversions from member
6110 functions, and pointers to member functions to
6111 pointer-to-function and pointer-to-void types. If
6112 -Wno-pmf-conversions has not been specified,
6113 convert_member_func_to_ptr will issue an error message. */
6114 if ((TYPE_PTRMEMFUNC_P (intype)
6115 || TREE_CODE (intype) == METHOD_TYPE)
6116 && TYPE_PTR_P (type)
6117 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
6118 || VOID_TYPE_P (TREE_TYPE (type))))
6119 return convert_member_func_to_ptr (type, expr);
6121 /* If the cast is not to a reference type, the lvalue-to-rvalue,
6122 array-to-pointer, and function-to-pointer conversions are
6124 expr = decay_conversion (expr);
6126 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6127 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
6128 if (TREE_CODE (expr) == NOP_EXPR
6129 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
6130 expr = TREE_OPERAND (expr, 0);
6132 if (error_operand_p (expr))
6133 return error_mark_node;
6135 intype = TREE_TYPE (expr);
6137 /* [expr.reinterpret.cast]
6138 A pointer can be converted to any integral type large enough to
6139 hold it. ... A value of type std::nullptr_t can be converted to
6140 an integral type; the conversion has the same meaning and
6141 validity as a conversion of (void*)0 to the integral type. */
6142 if (CP_INTEGRAL_TYPE_P (type)
6143 && (TYPE_PTR_P (intype) || NULLPTR_TYPE_P (intype)))
6145 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
6147 if (complain & tf_error)
6148 permerror (input_location, "cast from %qT to %qT loses precision",
6151 return error_mark_node;
6153 if (NULLPTR_TYPE_P (intype))
6154 return build_int_cst (type, 0);
6156 /* [expr.reinterpret.cast]
6157 A value of integral or enumeration type can be explicitly
6158 converted to a pointer. */
6159 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
6162 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
6163 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
6164 return fold_if_not_in_template (build_nop (type, expr));
6165 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
6166 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
6171 && check_for_casting_away_constness (intype, type,
6172 REINTERPRET_CAST_EXPR,
6174 return error_mark_node;
6175 /* Warn about possible alignment problems. */
6176 if (STRICT_ALIGNMENT && warn_cast_align
6177 && (complain & tf_warning)
6178 && !VOID_TYPE_P (type)
6179 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
6180 && COMPLETE_TYPE_P (TREE_TYPE (type))
6181 && COMPLETE_TYPE_P (TREE_TYPE (intype))
6182 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
6183 warning (OPT_Wcast_align, "cast from %qT to %qT "
6184 "increases required alignment of target type", intype, type);
6186 /* We need to strip nops here, because the front end likes to
6187 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
6189 if (warn_strict_aliasing <= 2)
6190 strict_aliasing_warning (intype, type, sexpr);
6192 return fold_if_not_in_template (build_nop (type, expr));
6194 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
6195 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
6197 if (pedantic && (complain & tf_warning))
6198 /* Only issue a warning, as we have always supported this
6199 where possible, and it is necessary in some cases. DR 195
6200 addresses this issue, but as of 2004/10/26 is still in
6202 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
6203 return fold_if_not_in_template (build_nop (type, expr));
6205 else if (TREE_CODE (type) == VECTOR_TYPE)
6206 return fold_if_not_in_template (convert_to_vector (type, expr));
6207 else if (TREE_CODE (intype) == VECTOR_TYPE
6208 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
6209 return fold_if_not_in_template (convert_to_integer (type, expr));
6214 if (complain & tf_error)
6215 error ("invalid cast from type %qT to type %qT", intype, type);
6216 return error_mark_node;
6219 return cp_convert (type, expr);
6223 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
6225 if (type == error_mark_node || expr == error_mark_node)
6226 return error_mark_node;
6228 if (processing_template_decl)
6230 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
6232 if (!TREE_SIDE_EFFECTS (t)
6233 && type_dependent_expression_p (expr))
6234 /* There might turn out to be side effects inside expr. */
6235 TREE_SIDE_EFFECTS (t) = 1;
6236 return convert_from_reference (t);
6239 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
6240 /*valid_p=*/NULL, complain);
6243 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
6244 return an appropriate expression. Otherwise, return
6245 error_mark_node. If the cast is not valid, and COMPLAIN is true,
6246 then a diagnostic will be issued. If VALID_P is non-NULL, we are
6247 performing a C-style cast, its value upon return will indicate
6248 whether or not the conversion succeeded. */
6251 build_const_cast_1 (tree dst_type, tree expr, tsubst_flags_t complain,
6255 tree reference_type;
6257 /* Callers are responsible for handling error_mark_node as a
6258 destination type. */
6259 gcc_assert (dst_type != error_mark_node);
6260 /* In a template, callers should be building syntactic
6261 representations of casts, not using this machinery. */
6262 gcc_assert (!processing_template_decl);
6264 /* Assume the conversion is invalid. */
6268 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
6270 if (complain & tf_error)
6271 error ("invalid use of const_cast with type %qT, "
6272 "which is not a pointer, "
6273 "reference, nor a pointer-to-data-member type", dst_type);
6274 return error_mark_node;
6277 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
6279 if (complain & tf_error)
6280 error ("invalid use of const_cast with type %qT, which is a pointer "
6281 "or reference to a function type", dst_type);
6282 return error_mark_node;
6285 /* Save casted types in the function's used types hash table. */
6286 used_types_insert (dst_type);
6288 src_type = TREE_TYPE (expr);
6289 /* Expressions do not really have reference types. */
6290 if (TREE_CODE (src_type) == REFERENCE_TYPE)
6291 src_type = TREE_TYPE (src_type);
6293 /* [expr.const.cast]
6295 For two object types T1 and T2, if a pointer to T1 can be explicitly
6296 converted to the type "pointer to T2" using a const_cast, then the
6297 following conversions can also be made:
6299 -- an lvalue of type T1 can be explicitly converted to an lvalue of
6300 type T2 using the cast const_cast<T2&>;
6302 -- a glvalue of type T1 can be explicitly converted to an xvalue of
6303 type T2 using the cast const_cast<T2&&>; and
6305 -- if T1 is a class type, a prvalue of type T1 can be explicitly
6306 converted to an xvalue of type T2 using the cast const_cast<T2&&>. */
6308 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
6310 reference_type = dst_type;
6311 if (!TYPE_REF_IS_RVALUE (dst_type)
6312 ? real_lvalue_p (expr)
6313 : (CLASS_TYPE_P (TREE_TYPE (dst_type))
6315 : lvalue_or_rvalue_with_address_p (expr)))
6319 if (complain & tf_error)
6320 error ("invalid const_cast of an rvalue of type %qT to type %qT",
6321 src_type, dst_type);
6322 return error_mark_node;
6324 dst_type = build_pointer_type (TREE_TYPE (dst_type));
6325 src_type = build_pointer_type (src_type);
6329 reference_type = NULL_TREE;
6330 /* If the destination type is not a reference type, the
6331 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6332 conversions are performed. */
6333 src_type = type_decays_to (src_type);
6334 if (src_type == error_mark_node)
6335 return error_mark_node;
6338 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
6339 && comp_ptr_ttypes_const (dst_type, src_type))
6344 /* This cast is actually a C-style cast. Issue a warning if
6345 the user is making a potentially unsafe cast. */
6346 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR,
6351 expr = cp_build_addr_expr (expr, complain);
6352 expr = build_nop (reference_type, expr);
6353 return convert_from_reference (expr);
6357 expr = decay_conversion (expr);
6358 /* build_c_cast puts on a NOP_EXPR to make the result not an
6359 lvalue. Strip such NOP_EXPRs if VALUE is being used in
6360 non-lvalue context. */
6361 if (TREE_CODE (expr) == NOP_EXPR
6362 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
6363 expr = TREE_OPERAND (expr, 0);
6364 return build_nop (dst_type, expr);
6368 if (complain & tf_error)
6369 error ("invalid const_cast from type %qT to type %qT",
6370 src_type, dst_type);
6371 return error_mark_node;
6375 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
6377 if (type == error_mark_node || error_operand_p (expr))
6378 return error_mark_node;
6380 if (processing_template_decl)
6382 tree t = build_min (CONST_CAST_EXPR, type, expr);
6384 if (!TREE_SIDE_EFFECTS (t)
6385 && type_dependent_expression_p (expr))
6386 /* There might turn out to be side effects inside expr. */
6387 TREE_SIDE_EFFECTS (t) = 1;
6388 return convert_from_reference (t);
6391 return build_const_cast_1 (type, expr, complain,
6395 /* Like cp_build_c_cast, but for the c-common bits. */
6398 build_c_cast (location_t loc ATTRIBUTE_UNUSED, tree type, tree expr)
6400 return cp_build_c_cast (type, expr, tf_warning_or_error);
6403 /* Build an expression representing an explicit C-style cast to type
6404 TYPE of expression EXPR. */
6407 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
6413 if (type == error_mark_node || error_operand_p (expr))
6414 return error_mark_node;
6416 if (processing_template_decl)
6418 tree t = build_min (CAST_EXPR, type,
6419 tree_cons (NULL_TREE, value, NULL_TREE));
6420 /* We don't know if it will or will not have side effects. */
6421 TREE_SIDE_EFFECTS (t) = 1;
6422 return convert_from_reference (t);
6425 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
6426 'Class') should always be retained, because this information aids
6427 in method lookup. */
6428 if (objc_is_object_ptr (type)
6429 && objc_is_object_ptr (TREE_TYPE (expr)))
6430 return build_nop (type, expr);
6432 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6433 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
6434 if (TREE_CODE (type) != REFERENCE_TYPE
6435 && TREE_CODE (value) == NOP_EXPR
6436 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
6437 value = TREE_OPERAND (value, 0);
6439 if (TREE_CODE (type) == ARRAY_TYPE)
6441 /* Allow casting from T1* to T2[] because Cfront allows it.
6442 NIHCL uses it. It is not valid ISO C++ however. */
6443 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
6445 if (complain & tf_error)
6446 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
6448 return error_mark_node;
6449 type = build_pointer_type (TREE_TYPE (type));
6453 if (complain & tf_error)
6454 error ("ISO C++ forbids casting to an array type %qT", type);
6455 return error_mark_node;
6459 if (TREE_CODE (type) == FUNCTION_TYPE
6460 || TREE_CODE (type) == METHOD_TYPE)
6462 if (complain & tf_error)
6463 error ("invalid cast to function type %qT", type);
6464 return error_mark_node;
6467 if (TREE_CODE (type) == POINTER_TYPE
6468 && TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
6469 /* Casting to an integer of smaller size is an error detected elsewhere. */
6470 && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (value))
6471 /* Don't warn about converting any constant. */
6472 && !TREE_CONSTANT (value))
6473 warning_at (input_location, OPT_Wint_to_pointer_cast,
6474 "cast to pointer from integer of different size");
6476 /* A C-style cast can be a const_cast. */
6477 result = build_const_cast_1 (type, value, complain & tf_warning,
6482 /* Or a static cast. */
6483 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
6484 &valid_p, complain);
6485 /* Or a reinterpret_cast. */
6487 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
6488 &valid_p, complain);
6489 /* The static_cast or reinterpret_cast may be followed by a
6492 /* A valid cast may result in errors if, for example, a
6493 conversion to am ambiguous base class is required. */
6494 && !error_operand_p (result))
6498 /* Non-class rvalues always have cv-unqualified type. */
6499 if (!CLASS_TYPE_P (type))
6500 type = TYPE_MAIN_VARIANT (type);
6501 result_type = TREE_TYPE (result);
6502 if (!CLASS_TYPE_P (result_type) && TREE_CODE (type) != REFERENCE_TYPE)
6503 result_type = TYPE_MAIN_VARIANT (result_type);
6504 /* If the type of RESULT does not match TYPE, perform a
6505 const_cast to make it match. If the static_cast or
6506 reinterpret_cast succeeded, we will differ by at most
6507 cv-qualification, so the follow-on const_cast is guaranteed
6509 if (!same_type_p (non_reference (type), non_reference (result_type)))
6511 result = build_const_cast_1 (type, result, false, &valid_p);
6512 gcc_assert (valid_p);
6517 return error_mark_node;
6520 /* For use from the C common bits. */
6522 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
6523 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
6524 enum tree_code modifycode,
6525 location_t rhs_location ATTRIBUTE_UNUSED, tree rhs,
6526 tree rhs_origtype ATTRIBUTE_UNUSED)
6528 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
6531 /* Build an assignment expression of lvalue LHS from value RHS.
6532 MODIFYCODE is the code for a binary operator that we use
6533 to combine the old value of LHS with RHS to get the new value.
6534 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
6536 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
6539 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6540 tsubst_flags_t complain)
6544 tree lhstype = TREE_TYPE (lhs);
6545 tree olhstype = lhstype;
6546 bool plain_assign = (modifycode == NOP_EXPR);
6548 /* Avoid duplicate error messages from operands that had errors. */
6549 if (error_operand_p (lhs) || error_operand_p (rhs))
6550 return error_mark_node;
6552 /* Handle control structure constructs used as "lvalues". */
6553 switch (TREE_CODE (lhs))
6555 /* Handle --foo = 5; as these are valid constructs in C++. */
6556 case PREDECREMENT_EXPR:
6557 case PREINCREMENT_EXPR:
6558 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6559 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6560 stabilize_reference (TREE_OPERAND (lhs, 0)),
6561 TREE_OPERAND (lhs, 1));
6562 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
6563 modifycode, rhs, complain);
6564 if (newrhs == error_mark_node)
6565 return error_mark_node;
6566 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6568 /* Handle (a, b) used as an "lvalue". */
6570 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6571 modifycode, rhs, complain);
6572 if (newrhs == error_mark_node)
6573 return error_mark_node;
6574 return build2 (COMPOUND_EXPR, lhstype,
6575 TREE_OPERAND (lhs, 0), newrhs);
6578 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6579 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6580 stabilize_reference (TREE_OPERAND (lhs, 0)),
6581 TREE_OPERAND (lhs, 1));
6582 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6584 if (newrhs == error_mark_node)
6585 return error_mark_node;
6586 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6590 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6591 when neither operand has side-effects. */
6592 if (!lvalue_or_else (lhs, lv_assign, complain))
6593 return error_mark_node;
6595 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6596 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6598 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6599 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6601 TREE_OPERAND (lhs, 0),
6602 TREE_OPERAND (lhs, 1)),
6603 TREE_OPERAND (lhs, 0),
6604 TREE_OPERAND (lhs, 1));
6607 /* Handle (a ? b : c) used as an "lvalue". */
6610 /* Produce (a ? (b = rhs) : (c = rhs))
6611 except that the RHS goes through a save-expr
6612 so the code to compute it is only emitted once. */
6614 tree preeval = NULL_TREE;
6616 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6618 if (complain & tf_error)
6619 error ("void value not ignored as it ought to be");
6620 return error_mark_node;
6623 rhs = stabilize_expr (rhs, &preeval);
6625 /* Check this here to avoid odd errors when trying to convert
6626 a throw to the type of the COND_EXPR. */
6627 if (!lvalue_or_else (lhs, lv_assign, complain))
6628 return error_mark_node;
6630 cond = build_conditional_expr
6631 (TREE_OPERAND (lhs, 0),
6632 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6633 modifycode, rhs, complain),
6634 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6635 modifycode, rhs, complain),
6638 if (cond == error_mark_node)
6640 /* Make sure the code to compute the rhs comes out
6641 before the split. */
6643 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6651 if (modifycode == INIT_EXPR)
6653 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6654 /* Do the default thing. */;
6655 else if (TREE_CODE (rhs) == CONSTRUCTOR)
6657 /* Compound literal. */
6658 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6659 /* Call convert to generate an error; see PR 11063. */
6660 rhs = convert (lhstype, rhs);
6661 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6662 TREE_SIDE_EFFECTS (result) = 1;
6665 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6666 /* Do the default thing. */;
6669 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6670 result = build_special_member_call (lhs, complete_ctor_identifier,
6671 &rhs_vec, lhstype, LOOKUP_NORMAL,
6673 release_tree_vector (rhs_vec);
6674 if (result == NULL_TREE)
6675 return error_mark_node;
6681 lhs = require_complete_type_sfinae (lhs, complain);
6682 if (lhs == error_mark_node)
6683 return error_mark_node;
6685 if (modifycode == NOP_EXPR)
6687 if (c_dialect_objc ())
6689 result = objc_maybe_build_modify_expr (lhs, rhs);
6694 /* `operator=' is not an inheritable operator. */
6695 if (! MAYBE_CLASS_TYPE_P (lhstype))
6696 /* Do the default thing. */;
6699 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6700 lhs, rhs, make_node (NOP_EXPR),
6703 if (result == NULL_TREE)
6704 return error_mark_node;
6711 tree init = NULL_TREE;
6713 /* A binary op has been requested. Combine the old LHS
6714 value with the RHS producing the value we should actually
6715 store into the LHS. */
6716 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6717 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6718 || MAYBE_CLASS_TYPE_P (lhstype)));
6720 /* Preevaluate the RHS to make sure its evaluation is complete
6721 before the lvalue-to-rvalue conversion of the LHS:
6723 [expr.ass] With respect to an indeterminately-sequenced
6724 function call, the operation of a compound assignment is a
6725 single evaluation. [ Note: Therefore, a function call shall
6726 not intervene between the lvalue-to-rvalue conversion and the
6727 side effect associated with any single compound assignment
6728 operator. -- end note ] */
6729 lhs = stabilize_reference (lhs);
6730 if (TREE_SIDE_EFFECTS (rhs))
6731 rhs = mark_rvalue_use (rhs);
6732 rhs = stabilize_expr (rhs, &init);
6733 newrhs = cp_build_binary_op (input_location,
6734 modifycode, lhs, rhs,
6736 if (newrhs == error_mark_node)
6738 if (complain & tf_error)
6739 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6740 TREE_TYPE (lhs), TREE_TYPE (rhs));
6741 return error_mark_node;
6745 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), init, newrhs);
6747 /* Now it looks like a plain assignment. */
6748 modifycode = NOP_EXPR;
6749 if (c_dialect_objc ())
6751 result = objc_maybe_build_modify_expr (lhs, newrhs);
6756 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6757 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6760 /* The left-hand side must be an lvalue. */
6761 if (!lvalue_or_else (lhs, lv_assign, complain))
6762 return error_mark_node;
6764 /* Warn about modifying something that is `const'. Don't warn if
6765 this is initialization. */
6766 if (modifycode != INIT_EXPR
6767 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6768 /* Functions are not modifiable, even though they are
6770 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6771 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6772 /* If it's an aggregate and any field is const, then it is
6773 effectively const. */
6774 || (CLASS_TYPE_P (lhstype)
6775 && C_TYPE_FIELDS_READONLY (lhstype))))
6777 if (complain & tf_error)
6778 cxx_readonly_error (lhs, lv_assign);
6780 return error_mark_node;
6783 /* If storing into a structure or union member, it may have been given a
6784 lowered bitfield type. We need to convert to the declared type first,
6785 so retrieve it now. */
6787 olhstype = unlowered_expr_type (lhs);
6789 /* Convert new value to destination type. */
6791 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6795 if (BRACE_ENCLOSED_INITIALIZER_P (newrhs))
6797 if (modifycode != INIT_EXPR)
6799 if (complain & tf_error)
6800 error ("assigning to an array from an initializer list");
6801 return error_mark_node;
6803 if (check_array_initializer (lhs, lhstype, newrhs))
6804 return error_mark_node;
6805 newrhs = digest_init (lhstype, newrhs, complain);
6806 if (newrhs == error_mark_node)
6807 return error_mark_node;
6810 else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6811 TYPE_MAIN_VARIANT (TREE_TYPE (newrhs))))
6813 if (complain & tf_error)
6814 error ("incompatible types in assignment of %qT to %qT",
6815 TREE_TYPE (rhs), lhstype);
6816 return error_mark_node;
6819 /* Allow array assignment in compiler-generated code. */
6820 else if (!current_function_decl
6821 || !DECL_DEFAULTED_FN (current_function_decl))
6823 /* This routine is used for both initialization and assignment.
6824 Make sure the diagnostic message differentiates the context. */
6825 if (complain & tf_error)
6827 if (modifycode == INIT_EXPR)
6828 error ("array used as initializer");
6830 error ("invalid array assignment");
6832 return error_mark_node;
6835 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6836 ? 1 + (modifycode != INIT_EXPR): 0;
6837 return build_vec_init (lhs, NULL_TREE, newrhs,
6838 /*explicit_value_init_p=*/false,
6839 from_array, complain);
6842 if (modifycode == INIT_EXPR)
6843 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6844 LOOKUP_ONLYCONVERTING. */
6845 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6846 ICR_INIT, NULL_TREE, 0,
6849 newrhs = convert_for_assignment (olhstype, newrhs, ICR_ASSIGN,
6850 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6852 if (!same_type_p (lhstype, olhstype))
6853 newrhs = cp_convert_and_check (lhstype, newrhs);
6855 if (modifycode != INIT_EXPR)
6857 if (TREE_CODE (newrhs) == CALL_EXPR
6858 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6859 newrhs = build_cplus_new (lhstype, newrhs, complain);
6861 /* Can't initialize directly from a TARGET_EXPR, since that would
6862 cause the lhs to be constructed twice, and possibly result in
6863 accidental self-initialization. So we force the TARGET_EXPR to be
6864 expanded without a target. */
6865 if (TREE_CODE (newrhs) == TARGET_EXPR)
6866 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6867 TREE_OPERAND (newrhs, 0));
6870 if (newrhs == error_mark_node)
6871 return error_mark_node;
6873 if (c_dialect_objc () && flag_objc_gc)
6875 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6881 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6882 lhstype, lhs, newrhs);
6884 TREE_SIDE_EFFECTS (result) = 1;
6886 TREE_NO_WARNING (result) = 1;
6892 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6893 tsubst_flags_t complain)
6895 if (processing_template_decl)
6896 return build_min_nt (MODOP_EXPR, lhs,
6897 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6899 if (modifycode != NOP_EXPR)
6901 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6902 make_node (modifycode),
6907 TREE_NO_WARNING (rval) = 1;
6911 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6914 /* Helper function for get_delta_difference which assumes FROM is a base
6915 class of TO. Returns a delta for the conversion of pointer-to-member
6916 of FROM to pointer-to-member of TO. If the conversion is invalid and
6917 tf_error is not set in COMPLAIN returns error_mark_node, otherwise
6918 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6919 If C_CAST_P is true, this conversion is taking place as part of a
6923 get_delta_difference_1 (tree from, tree to, bool c_cast_p,
6924 tsubst_flags_t complain)
6928 base_access access = c_cast_p ? ba_unique : ba_check;
6930 /* Note: ba_quiet does not distinguish between access control and
6932 if (!(complain & tf_error))
6935 binfo = lookup_base (to, from, access, &kind);
6937 if (kind == bk_inaccessible || kind == bk_ambig)
6939 if (!(complain & tf_error))
6940 return error_mark_node;
6942 error (" in pointer to member function conversion");
6943 return size_zero_node;
6947 if (kind != bk_via_virtual)
6948 return BINFO_OFFSET (binfo);
6950 /* FROM is a virtual base class of TO. Issue an error or warning
6951 depending on whether or not this is a reinterpret cast. */
6953 if (!(complain & tf_error))
6954 return error_mark_node;
6956 error ("pointer to member conversion via virtual base %qT",
6957 BINFO_TYPE (binfo_from_vbase (binfo)));
6959 return size_zero_node;
6966 /* Get difference in deltas for different pointer to member function
6967 types. If the conversion is invalid and tf_error is not set in
6968 COMPLAIN, returns error_mark_node, otherwise returns an integer
6969 constant of type PTRDIFF_TYPE_NODE and its value is zero if the
6970 conversion is invalid. If ALLOW_INVERSE_P is true, then allow reverse
6971 conversions as well. If C_CAST_P is true this conversion is taking
6972 place as part of a C-style cast.
6974 Note that the naming of FROM and TO is kind of backwards; the return
6975 value is what we add to a TO in order to get a FROM. They are named
6976 this way because we call this function to find out how to convert from
6977 a pointer to member of FROM to a pointer to member of TO. */
6980 get_delta_difference (tree from, tree to,
6981 bool allow_inverse_p,
6982 bool c_cast_p, tsubst_flags_t complain)
6986 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6987 /* Pointer to member of incomplete class is permitted*/
6988 result = size_zero_node;
6990 result = get_delta_difference_1 (from, to, c_cast_p, complain);
6992 if (result == error_mark_node)
6993 return error_mark_node;
6997 if (!allow_inverse_p)
6999 if (!(complain & tf_error))
7000 return error_mark_node;
7002 error_not_base_type (from, to);
7003 error (" in pointer to member conversion");
7004 result = size_zero_node;
7008 result = get_delta_difference_1 (to, from, c_cast_p, complain);
7010 if (result == error_mark_node)
7011 return error_mark_node;
7014 result = size_diffop_loc (input_location,
7015 size_zero_node, result);
7018 if (!(complain & tf_error))
7019 return error_mark_node;
7021 error_not_base_type (from, to);
7022 error (" in pointer to member conversion");
7023 result = size_zero_node;
7028 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
7032 /* Return a constructor for the pointer-to-member-function TYPE using
7033 the other components as specified. */
7036 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
7041 VEC(constructor_elt, gc) *v;
7043 /* Pull the FIELD_DECLs out of the type. */
7044 pfn_field = TYPE_FIELDS (type);
7045 delta_field = DECL_CHAIN (pfn_field);
7047 /* Make sure DELTA has the type we want. */
7048 delta = convert_and_check (delta_type_node, delta);
7050 /* Convert to the correct target type if necessary. */
7051 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
7053 /* Finish creating the initializer. */
7054 v = VEC_alloc(constructor_elt, gc, 2);
7055 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
7056 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
7057 u = build_constructor (type, v);
7058 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
7059 TREE_STATIC (u) = (TREE_CONSTANT (u)
7060 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
7062 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
7067 /* Build a constructor for a pointer to member function. It can be
7068 used to initialize global variables, local variable, or used
7069 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
7072 If FORCE is nonzero, then force this conversion, even if
7073 we would rather not do it. Usually set when using an explicit
7074 cast. A C-style cast is being processed iff C_CAST_P is true.
7076 Return error_mark_node, if something goes wrong. */
7079 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p,
7080 tsubst_flags_t complain)
7086 if (error_operand_p (pfn))
7087 return error_mark_node;
7089 pfn_type = TREE_TYPE (pfn);
7090 to_type = build_ptrmemfunc_type (type);
7092 /* Handle multiple conversions of pointer to member functions. */
7093 if (TYPE_PTRMEMFUNC_P (pfn_type))
7095 tree delta = NULL_TREE;
7096 tree npfn = NULL_TREE;
7100 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
7101 error ("invalid conversion to type %qT from type %qT",
7104 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
7105 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
7107 c_cast_p, complain);
7108 if (n == error_mark_node)
7109 return error_mark_node;
7111 /* We don't have to do any conversion to convert a
7112 pointer-to-member to its own type. But, we don't want to
7113 just return a PTRMEM_CST if there's an explicit cast; that
7114 cast should make the expression an invalid template argument. */
7115 if (TREE_CODE (pfn) != PTRMEM_CST)
7117 if (same_type_p (to_type, pfn_type))
7119 else if (integer_zerop (n))
7120 return build_reinterpret_cast (to_type, pfn,
7121 tf_warning_or_error);
7124 if (TREE_SIDE_EFFECTS (pfn))
7125 pfn = save_expr (pfn);
7127 /* Obtain the function pointer and the current DELTA. */
7128 if (TREE_CODE (pfn) == PTRMEM_CST)
7129 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
7132 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
7133 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
7136 /* Just adjust the DELTA field. */
7137 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7138 (TREE_TYPE (delta), ptrdiff_type_node));
7139 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
7140 n = cp_build_binary_op (input_location,
7141 LSHIFT_EXPR, n, integer_one_node,
7142 tf_warning_or_error);
7143 delta = cp_build_binary_op (input_location,
7144 PLUS_EXPR, delta, n, tf_warning_or_error);
7145 return build_ptrmemfunc1 (to_type, delta, npfn);
7148 /* Handle null pointer to member function conversions. */
7149 if (null_ptr_cst_p (pfn))
7151 pfn = build_c_cast (input_location, type, integer_zero_node);
7152 return build_ptrmemfunc1 (to_type,
7157 if (type_unknown_p (pfn))
7158 return instantiate_type (type, pfn, tf_warning_or_error);
7160 fn = TREE_OPERAND (pfn, 0);
7161 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
7162 /* In a template, we will have preserved the
7164 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
7165 return make_ptrmem_cst (to_type, fn);
7168 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
7171 ??? There is no consistency as to the types returned for the above
7172 values. Some code acts as if it were a sizetype and some as if it were
7173 integer_type_node. */
7176 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
7178 tree type = TREE_TYPE (cst);
7179 tree fn = PTRMEM_CST_MEMBER (cst);
7180 tree ptr_class, fn_class;
7182 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
7184 /* The class that the function belongs to. */
7185 fn_class = DECL_CONTEXT (fn);
7187 /* The class that we're creating a pointer to member of. */
7188 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
7190 /* First, calculate the adjustment to the function's class. */
7191 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
7192 /*c_cast_p=*/0, tf_warning_or_error);
7194 if (!DECL_VIRTUAL_P (fn))
7195 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
7198 /* If we're dealing with a virtual function, we have to adjust 'this'
7199 again, to point to the base which provides the vtable entry for
7200 fn; the call will do the opposite adjustment. */
7201 tree orig_class = DECL_CONTEXT (fn);
7202 tree binfo = binfo_or_else (orig_class, fn_class);
7203 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
7204 *delta, BINFO_OFFSET (binfo));
7205 *delta = fold_if_not_in_template (*delta);
7207 /* We set PFN to the vtable offset at which the function can be
7208 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
7209 case delta is shifted left, and then incremented). */
7210 *pfn = DECL_VINDEX (fn);
7211 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
7212 TYPE_SIZE_UNIT (vtable_entry_type));
7213 *pfn = fold_if_not_in_template (*pfn);
7215 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
7217 case ptrmemfunc_vbit_in_pfn:
7218 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
7220 *pfn = fold_if_not_in_template (*pfn);
7223 case ptrmemfunc_vbit_in_delta:
7224 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
7225 *delta, integer_one_node);
7226 *delta = fold_if_not_in_template (*delta);
7227 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
7228 *delta, integer_one_node);
7229 *delta = fold_if_not_in_template (*delta);
7236 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
7237 *pfn = fold_if_not_in_template (*pfn);
7241 /* Return an expression for PFN from the pointer-to-member function
7245 pfn_from_ptrmemfunc (tree t)
7247 if (TREE_CODE (t) == PTRMEM_CST)
7252 expand_ptrmemfunc_cst (t, &delta, &pfn);
7257 return build_ptrmemfunc_access_expr (t, pfn_identifier);
7260 /* Return an expression for DELTA from the pointer-to-member function
7264 delta_from_ptrmemfunc (tree t)
7266 if (TREE_CODE (t) == PTRMEM_CST)
7271 expand_ptrmemfunc_cst (t, &delta, &pfn);
7276 return build_ptrmemfunc_access_expr (t, delta_identifier);
7279 /* Convert value RHS to type TYPE as preparation for an assignment to
7280 an lvalue of type TYPE. ERRTYPE indicates what kind of error the
7281 implicit conversion is. If FNDECL is non-NULL, we are doing the
7282 conversion in order to pass the PARMNUMth argument of FNDECL.
7283 If FNDECL is NULL, we are doing the conversion in function pointer
7284 argument passing, conversion in initialization, etc. */
7287 convert_for_assignment (tree type, tree rhs,
7288 impl_conv_rhs errtype, tree fndecl, int parmnum,
7289 tsubst_flags_t complain, int flags)
7292 enum tree_code coder;
7294 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
7295 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
7296 rhs = TREE_OPERAND (rhs, 0);
7298 rhstype = TREE_TYPE (rhs);
7299 coder = TREE_CODE (rhstype);
7301 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
7302 && vector_types_convertible_p (type, rhstype, true))
7304 rhs = mark_rvalue_use (rhs);
7305 return convert (type, rhs);
7308 if (rhs == error_mark_node || rhstype == error_mark_node)
7309 return error_mark_node;
7310 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
7311 return error_mark_node;
7313 /* The RHS of an assignment cannot have void type. */
7314 if (coder == VOID_TYPE)
7316 if (complain & tf_error)
7317 error ("void value not ignored as it ought to be");
7318 return error_mark_node;
7321 /* Simplify the RHS if possible. */
7322 if (TREE_CODE (rhs) == CONST_DECL)
7323 rhs = DECL_INITIAL (rhs);
7325 if (c_dialect_objc ())
7329 tree rname = fndecl;
7340 selector = objc_message_selector ();
7342 if (selector && parmno > 1)
7349 if (objc_compare_types (type, rhstype, parmno, rname))
7351 rhs = mark_rvalue_use (rhs);
7352 return convert (type, rhs);
7358 The expression is implicitly converted (clause _conv_) to the
7359 cv-unqualified type of the left operand.
7361 We allow bad conversions here because by the time we get to this point
7362 we are committed to doing the conversion. If we end up doing a bad
7363 conversion, convert_like will complain. */
7364 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
7366 /* When -Wno-pmf-conversions is use, we just silently allow
7367 conversions from pointers-to-members to plain pointers. If
7368 the conversion doesn't work, cp_convert will complain. */
7370 && TYPE_PTR_P (type)
7371 && TYPE_PTRMEMFUNC_P (rhstype))
7372 rhs = cp_convert (strip_top_quals (type), rhs);
7375 if (complain & tf_error)
7377 /* If the right-hand side has unknown type, then it is an
7378 overloaded function. Call instantiate_type to get error
7380 if (rhstype == unknown_type_node)
7381 instantiate_type (type, rhs, tf_warning_or_error);
7383 error ("cannot convert %qT to %qT for argument %qP to %qD",
7384 rhstype, type, parmnum, fndecl);
7388 case ICR_DEFAULT_ARGUMENT:
7389 error ("cannot convert %qT to %qT in default argument",
7393 error ("cannot convert %qT to %qT in argument passing",
7396 case ICR_CONVERTING:
7397 error ("cannot convert %qT to %qT",
7401 error ("cannot convert %qT to %qT in initialization",
7405 error ("cannot convert %qT to %qT in return",
7409 error ("cannot convert %qT to %qT in assignment",
7416 return error_mark_node;
7419 if (warn_missing_format_attribute)
7421 const enum tree_code codel = TREE_CODE (type);
7422 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
7424 && check_missing_format_attribute (type, rhstype)
7425 && (complain & tf_warning))
7429 case ICR_DEFAULT_ARGUMENT:
7431 warning (OPT_Wmissing_format_attribute,
7432 "parameter %qP of %qD might be a candidate "
7433 "for a format attribute", parmnum, fndecl);
7435 warning (OPT_Wmissing_format_attribute,
7436 "parameter might be a candidate "
7437 "for a format attribute");
7439 case ICR_CONVERTING:
7440 warning (OPT_Wmissing_format_attribute,
7441 "target of conversion might be a candidate "
7442 "for a format attribute");
7445 warning (OPT_Wmissing_format_attribute,
7446 "target of initialization might be a candidate "
7447 "for a format attribute");
7450 warning (OPT_Wmissing_format_attribute,
7451 "return type might be a candidate "
7452 "for a format attribute");
7455 warning (OPT_Wmissing_format_attribute,
7456 "left-hand side of assignment might be a candidate "
7457 "for a format attribute");
7464 /* If -Wparentheses, warn about a = b = c when a has type bool and b
7466 if (warn_parentheses
7467 && TREE_CODE (type) == BOOLEAN_TYPE
7468 && TREE_CODE (rhs) == MODIFY_EXPR
7469 && !TREE_NO_WARNING (rhs)
7470 && TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE
7471 && (complain & tf_warning))
7473 location_t loc = EXPR_LOC_OR_HERE (rhs);
7475 warning_at (loc, OPT_Wparentheses,
7476 "suggest parentheses around assignment used as truth value");
7477 TREE_NO_WARNING (rhs) = 1;
7480 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
7484 /* Convert RHS to be of type TYPE.
7485 If EXP is nonzero, it is the target of the initialization.
7486 ERRTYPE indicates what kind of error the implicit conversion is.
7488 Two major differences between the behavior of
7489 `convert_for_assignment' and `convert_for_initialization'
7490 are that references are bashed in the former, while
7491 copied in the latter, and aggregates are assigned in
7492 the former (operator=) while initialized in the
7495 If using constructor make sure no conversion operator exists, if one does
7496 exist, an ambiguity exists.
7498 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
7501 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
7502 impl_conv_rhs errtype, tree fndecl, int parmnum,
7503 tsubst_flags_t complain)
7505 enum tree_code codel = TREE_CODE (type);
7507 enum tree_code coder;
7509 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
7510 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
7511 if (TREE_CODE (rhs) == NOP_EXPR
7512 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
7513 && codel != REFERENCE_TYPE)
7514 rhs = TREE_OPERAND (rhs, 0);
7516 if (type == error_mark_node
7517 || rhs == error_mark_node
7518 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
7519 return error_mark_node;
7521 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
7522 && TREE_CODE (type) != ARRAY_TYPE
7523 && (TREE_CODE (type) != REFERENCE_TYPE
7524 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
7525 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
7526 && (TREE_CODE (type) != REFERENCE_TYPE
7527 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
7528 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
7529 rhs = decay_conversion (rhs);
7531 rhstype = TREE_TYPE (rhs);
7532 coder = TREE_CODE (rhstype);
7534 if (coder == ERROR_MARK)
7535 return error_mark_node;
7537 /* We accept references to incomplete types, so we can
7538 return here before checking if RHS is of complete type. */
7540 if (codel == REFERENCE_TYPE)
7542 /* This should eventually happen in convert_arguments. */
7543 int savew = 0, savee = 0;
7546 savew = warningcount, savee = errorcount;
7547 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
7548 /*cleanup=*/NULL, flags, complain);
7551 if (warningcount > savew)
7552 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
7553 else if (errorcount > savee)
7554 error ("in passing argument %P of %q+D", parmnum, fndecl);
7560 exp = require_complete_type_sfinae (exp, complain);
7561 if (exp == error_mark_node)
7562 return error_mark_node;
7564 rhstype = non_reference (rhstype);
7566 type = complete_type (type);
7568 if (DIRECT_INIT_EXPR_P (type, rhs))
7569 /* Don't try to do copy-initialization if we already have
7570 direct-initialization. */
7573 if (MAYBE_CLASS_TYPE_P (type))
7574 return perform_implicit_conversion_flags (type, rhs, complain, flags);
7576 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
7580 /* If RETVAL is the address of, or a reference to, a local variable or
7581 temporary give an appropriate warning. */
7584 maybe_warn_about_returning_address_of_local (tree retval)
7586 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
7587 tree whats_returned = retval;
7591 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
7592 whats_returned = TREE_OPERAND (whats_returned, 1);
7593 else if (CONVERT_EXPR_P (whats_returned)
7594 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
7595 whats_returned = TREE_OPERAND (whats_returned, 0);
7600 if (TREE_CODE (whats_returned) != ADDR_EXPR)
7602 whats_returned = TREE_OPERAND (whats_returned, 0);
7604 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7606 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
7607 || TREE_CODE (whats_returned) == TARGET_EXPR)
7609 warning (0, "returning reference to temporary");
7612 if (TREE_CODE (whats_returned) == VAR_DECL
7613 && DECL_NAME (whats_returned)
7614 && TEMP_NAME_P (DECL_NAME (whats_returned)))
7616 warning (0, "reference to non-lvalue returned");
7621 while (TREE_CODE (whats_returned) == COMPONENT_REF
7622 || TREE_CODE (whats_returned) == ARRAY_REF)
7623 whats_returned = TREE_OPERAND (whats_returned, 0);
7625 if (DECL_P (whats_returned)
7626 && DECL_NAME (whats_returned)
7627 && DECL_FUNCTION_SCOPE_P (whats_returned)
7628 && !(TREE_STATIC (whats_returned)
7629 || TREE_PUBLIC (whats_returned)))
7631 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7632 warning (0, "reference to local variable %q+D returned",
7635 warning (0, "address of local variable %q+D returned",
7641 /* Check that returning RETVAL from the current function is valid.
7642 Return an expression explicitly showing all conversions required to
7643 change RETVAL into the function return type, and to assign it to
7644 the DECL_RESULT for the function. Set *NO_WARNING to true if
7645 code reaches end of non-void function warning shouldn't be issued
7646 on this RETURN_EXPR. */
7649 check_return_expr (tree retval, bool *no_warning)
7652 /* The type actually returned by the function, after any
7655 int fn_returns_value_p;
7656 bool named_return_value_okay_p;
7658 *no_warning = false;
7660 /* A `volatile' function is one that isn't supposed to return, ever.
7661 (This is a G++ extension, used to get better code for functions
7662 that call the `volatile' function.) */
7663 if (TREE_THIS_VOLATILE (current_function_decl))
7664 warning (0, "function declared %<noreturn%> has a %<return%> statement");
7666 /* Check for various simple errors. */
7667 if (DECL_DESTRUCTOR_P (current_function_decl))
7670 error ("returning a value from a destructor");
7673 else if (DECL_CONSTRUCTOR_P (current_function_decl))
7675 if (in_function_try_handler)
7676 /* If a return statement appears in a handler of the
7677 function-try-block of a constructor, the program is ill-formed. */
7678 error ("cannot return from a handler of a function-try-block of a constructor");
7680 /* You can't return a value from a constructor. */
7681 error ("returning a value from a constructor");
7685 /* As an extension, deduce lambda return type from a return statement
7686 anywhere in the body. */
7687 if (retval && LAMBDA_FUNCTION_P (current_function_decl))
7689 tree lambda = CLASSTYPE_LAMBDA_EXPR (current_class_type);
7690 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
7692 tree type = lambda_return_type (retval);
7693 tree oldtype = LAMBDA_EXPR_RETURN_TYPE (lambda);
7695 if (oldtype == NULL_TREE)
7696 apply_lambda_return_type (lambda, type);
7697 /* If one of the answers is type-dependent, we can't do any
7698 better until instantiation time. */
7699 else if (oldtype == dependent_lambda_return_type_node)
7701 else if (type == dependent_lambda_return_type_node)
7702 apply_lambda_return_type (lambda, type);
7703 else if (!same_type_p (type, oldtype))
7704 error ("inconsistent types %qT and %qT deduced for "
7705 "lambda return type", type, oldtype);
7709 if (processing_template_decl)
7711 current_function_returns_value = 1;
7712 if (check_for_bare_parameter_packs (retval))
7713 retval = error_mark_node;
7717 /* When no explicit return-value is given in a function with a named
7718 return value, the named return value is used. */
7719 result = DECL_RESULT (current_function_decl);
7720 valtype = TREE_TYPE (result);
7721 gcc_assert (valtype != NULL_TREE);
7722 fn_returns_value_p = !VOID_TYPE_P (valtype);
7723 if (!retval && DECL_NAME (result) && fn_returns_value_p)
7726 /* Check for a return statement with no return value in a function
7727 that's supposed to return a value. */
7728 if (!retval && fn_returns_value_p)
7730 permerror (input_location, "return-statement with no value, in function returning %qT",
7732 /* Clear this, so finish_function won't say that we reach the
7733 end of a non-void function (which we don't, we gave a
7735 current_function_returns_null = 0;
7736 /* And signal caller that TREE_NO_WARNING should be set on the
7737 RETURN_EXPR to avoid control reaches end of non-void function
7738 warnings in tree-cfg.c. */
7741 /* Check for a return statement with a value in a function that
7742 isn't supposed to return a value. */
7743 else if (retval && !fn_returns_value_p)
7745 if (VOID_TYPE_P (TREE_TYPE (retval)))
7746 /* You can return a `void' value from a function of `void'
7747 type. In that case, we have to evaluate the expression for
7748 its side-effects. */
7749 finish_expr_stmt (retval);
7751 permerror (input_location, "return-statement with a value, in function "
7752 "returning 'void'");
7753 current_function_returns_null = 1;
7755 /* There's really no value to return, after all. */
7759 /* Remember that this function can sometimes return without a
7761 current_function_returns_null = 1;
7763 /* Remember that this function did return a value. */
7764 current_function_returns_value = 1;
7766 /* Check for erroneous operands -- but after giving ourselves a
7767 chance to provide an error about returning a value from a void
7769 if (error_operand_p (retval))
7771 current_function_return_value = error_mark_node;
7772 return error_mark_node;
7775 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7776 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7777 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7778 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7780 && retval && null_ptr_cst_p (retval))
7781 warning (0, "%<operator new%> must not return NULL unless it is "
7782 "declared %<throw()%> (or -fcheck-new is in effect)");
7784 /* Effective C++ rule 15. See also start_function. */
7786 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7790 /* The function return type must be a reference to the current
7792 if (TREE_CODE (valtype) == REFERENCE_TYPE
7793 && same_type_ignoring_top_level_qualifiers_p
7794 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7796 /* Returning '*this' is obviously OK. */
7797 if (retval == current_class_ref)
7799 /* If we are calling a function whose return type is the same of
7800 the current class reference, it is ok. */
7801 else if (TREE_CODE (retval) == INDIRECT_REF
7802 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7807 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7810 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7812 [...] For a function with a class return type, if the expression
7813 in the return statement is the name of a local object, and the cv-
7814 unqualified type of the local object is the same as the function
7815 return type, an implementation is permitted to omit creating the tem-
7816 porary object to hold the function return value [...]
7818 So, if this is a value-returning function that always returns the same
7819 local variable, remember it.
7821 It might be nice to be more flexible, and choose the first suitable
7822 variable even if the function sometimes returns something else, but
7823 then we run the risk of clobbering the variable we chose if the other
7824 returned expression uses the chosen variable somehow. And people expect
7825 this restriction, anyway. (jason 2000-11-19)
7827 See finish_function and finalize_nrv for the rest of this optimization. */
7829 named_return_value_okay_p =
7830 (retval != NULL_TREE
7831 /* Must be a local, automatic variable. */
7832 && TREE_CODE (retval) == VAR_DECL
7833 && DECL_CONTEXT (retval) == current_function_decl
7834 && ! TREE_STATIC (retval)
7835 && ! DECL_ANON_UNION_VAR_P (retval)
7836 && (DECL_ALIGN (retval)
7837 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7838 /* The cv-unqualified type of the returned value must be the
7839 same as the cv-unqualified return type of the
7841 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7843 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7844 /* And the returned value must be non-volatile. */
7845 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7847 if (fn_returns_value_p && flag_elide_constructors)
7849 if (named_return_value_okay_p
7850 && (current_function_return_value == NULL_TREE
7851 || current_function_return_value == retval))
7852 current_function_return_value = retval;
7854 current_function_return_value = error_mark_node;
7857 /* We don't need to do any conversions when there's nothing being
7862 /* Do any required conversions. */
7863 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7864 /* No conversions are required. */
7868 /* The type the function is declared to return. */
7869 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7870 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7872 /* The functype's return type will have been set to void, if it
7873 was an incomplete type. Just treat this as 'return;' */
7874 if (VOID_TYPE_P (functype))
7875 return error_mark_node;
7877 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7878 treated as an rvalue for the purposes of overload resolution to
7879 favor move constructors over copy constructors.
7881 Note that these conditions are similar to, but not as strict as,
7882 the conditions for the named return value optimization. */
7883 if ((cxx_dialect != cxx98)
7884 && (TREE_CODE (retval) == VAR_DECL
7885 || TREE_CODE (retval) == PARM_DECL)
7886 && DECL_CONTEXT (retval) == current_function_decl
7887 && !TREE_STATIC (retval)
7888 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7890 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7891 /* This is only interesting for class type. */
7892 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7893 flags = flags | LOOKUP_PREFER_RVALUE;
7895 /* First convert the value to the function's return type, then
7896 to the type of return value's location to handle the
7897 case that functype is smaller than the valtype. */
7898 retval = convert_for_initialization
7899 (NULL_TREE, functype, retval, flags, ICR_RETURN, NULL_TREE, 0,
7900 tf_warning_or_error);
7901 retval = convert (valtype, retval);
7903 /* If the conversion failed, treat this just like `return;'. */
7904 if (retval == error_mark_node)
7906 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7907 else if (! cfun->returns_struct
7908 && TREE_CODE (retval) == TARGET_EXPR
7909 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7910 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7911 TREE_OPERAND (retval, 0));
7913 maybe_warn_about_returning_address_of_local (retval);
7916 /* Actually copy the value returned into the appropriate location. */
7917 if (retval && retval != result)
7918 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7924 /* Returns nonzero if the pointer-type FROM can be converted to the
7925 pointer-type TO via a qualification conversion. If CONSTP is -1,
7926 then we return nonzero if the pointers are similar, and the
7927 cv-qualification signature of FROM is a proper subset of that of TO.
7929 If CONSTP is positive, then all outer pointers have been
7933 comp_ptr_ttypes_real (tree to, tree from, int constp)
7935 bool to_more_cv_qualified = false;
7936 bool is_opaque_pointer = false;
7938 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7940 if (TREE_CODE (to) != TREE_CODE (from))
7943 if (TREE_CODE (from) == OFFSET_TYPE
7944 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7945 TYPE_OFFSET_BASETYPE (to)))
7948 /* Const and volatile mean something different for function types,
7949 so the usual checks are not appropriate. */
7950 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7952 if (!at_least_as_qualified_p (to, from))
7955 if (!at_least_as_qualified_p (from, to))
7959 to_more_cv_qualified = true;
7963 constp &= TYPE_READONLY (to);
7966 if (TREE_CODE (to) == VECTOR_TYPE)
7967 is_opaque_pointer = vector_targets_convertible_p (to, from);
7969 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7970 return ((constp >= 0 || to_more_cv_qualified)
7971 && (is_opaque_pointer
7972 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7976 /* When comparing, say, char ** to char const **, this function takes
7977 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7978 types to this function. */
7981 comp_ptr_ttypes (tree to, tree from)
7983 return comp_ptr_ttypes_real (to, from, 1);
7986 /* Returns true iff FNTYPE is a non-class type that involves
7987 error_mark_node. We can get FUNCTION_TYPE with buried error_mark_node
7988 if a parameter type is ill-formed. */
7991 error_type_p (const_tree type)
7995 switch (TREE_CODE (type))
8001 case REFERENCE_TYPE:
8003 return error_type_p (TREE_TYPE (type));
8007 if (error_type_p (TREE_TYPE (type)))
8009 for (t = TYPE_ARG_TYPES (type); t; t = TREE_CHAIN (t))
8010 if (error_type_p (TREE_VALUE (t)))
8015 if (TYPE_PTRMEMFUNC_P (type))
8016 return error_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type));
8024 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
8025 type or inheritance-related types, regardless of cv-quals. */
8028 ptr_reasonably_similar (const_tree to, const_tree from)
8030 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
8032 /* Any target type is similar enough to void. */
8033 if (TREE_CODE (to) == VOID_TYPE)
8034 return !error_type_p (from);
8035 if (TREE_CODE (from) == VOID_TYPE)
8036 return !error_type_p (to);
8038 if (TREE_CODE (to) != TREE_CODE (from))
8041 if (TREE_CODE (from) == OFFSET_TYPE
8042 && comptypes (TYPE_OFFSET_BASETYPE (to),
8043 TYPE_OFFSET_BASETYPE (from),
8044 COMPARE_BASE | COMPARE_DERIVED))
8047 if (TREE_CODE (to) == VECTOR_TYPE
8048 && vector_types_convertible_p (to, from, false))
8051 if (TREE_CODE (to) == INTEGER_TYPE
8052 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
8055 if (TREE_CODE (to) == FUNCTION_TYPE)
8056 return !error_type_p (to) && !error_type_p (from);
8058 if (TREE_CODE (to) != POINTER_TYPE)
8060 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
8061 COMPARE_BASE | COMPARE_DERIVED);
8065 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
8066 pointer-to-member types) are the same, ignoring cv-qualification at
8070 comp_ptr_ttypes_const (tree to, tree from)
8072 bool is_opaque_pointer = false;
8074 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
8076 if (TREE_CODE (to) != TREE_CODE (from))
8079 if (TREE_CODE (from) == OFFSET_TYPE
8080 && same_type_p (TYPE_OFFSET_BASETYPE (from),
8081 TYPE_OFFSET_BASETYPE (to)))
8084 if (TREE_CODE (to) == VECTOR_TYPE)
8085 is_opaque_pointer = vector_targets_convertible_p (to, from);
8087 if (TREE_CODE (to) != POINTER_TYPE)
8088 return (is_opaque_pointer
8089 || same_type_ignoring_top_level_qualifiers_p (to, from));
8093 /* Returns the type qualifiers for this type, including the qualifiers on the
8094 elements for an array type. */
8097 cp_type_quals (const_tree type)
8100 /* This CONST_CAST is okay because strip_array_types returns its
8101 argument unmodified and we assign it to a const_tree. */
8102 type = strip_array_types (CONST_CAST_TREE (type));
8103 if (type == error_mark_node
8104 /* Quals on a FUNCTION_TYPE are memfn quals. */
8105 || TREE_CODE (type) == FUNCTION_TYPE)
8106 return TYPE_UNQUALIFIED;
8107 quals = TYPE_QUALS (type);
8108 /* METHOD and REFERENCE_TYPEs should never have quals. */
8109 gcc_assert ((TREE_CODE (type) != METHOD_TYPE
8110 && TREE_CODE (type) != REFERENCE_TYPE)
8111 || ((quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE))
8112 == TYPE_UNQUALIFIED));
8116 /* Returns the function-cv-quals for TYPE, which must be a FUNCTION_TYPE or
8120 type_memfn_quals (const_tree type)
8122 if (TREE_CODE (type) == FUNCTION_TYPE)
8123 return TYPE_QUALS (type);
8124 else if (TREE_CODE (type) == METHOD_TYPE)
8125 return cp_type_quals (class_of_this_parm (type));
8130 /* Returns the FUNCTION_TYPE TYPE with its function-cv-quals changed to
8134 apply_memfn_quals (tree type, cp_cv_quals memfn_quals)
8136 /* Could handle METHOD_TYPE here if necessary. */
8137 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
8138 if (TYPE_QUALS (type) == memfn_quals)
8140 /* This should really have a different TYPE_MAIN_VARIANT, but that gets
8142 return build_qualified_type (type, memfn_quals);
8145 /* Returns nonzero if TYPE is const or volatile. */
8148 cv_qualified_p (const_tree type)
8150 int quals = cp_type_quals (type);
8151 return (quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE)) != 0;
8154 /* Returns nonzero if the TYPE contains a mutable member. */
8157 cp_has_mutable_p (const_tree type)
8159 /* This CONST_CAST is okay because strip_array_types returns its
8160 argument unmodified and we assign it to a const_tree. */
8161 type = strip_array_types (CONST_CAST_TREE(type));
8163 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
8166 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
8167 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
8168 approximation. In particular, consider:
8171 struct S { int i; };
8172 const S s = { f(); }
8174 Here, we will make "s" as TREE_READONLY (because it is declared
8175 "const") -- only to reverse ourselves upon seeing that the
8176 initializer is non-constant. */
8179 cp_apply_type_quals_to_decl (int type_quals, tree decl)
8181 tree type = TREE_TYPE (decl);
8183 if (type == error_mark_node)
8186 if (TREE_CODE (decl) == TYPE_DECL)
8189 gcc_assert (!(TREE_CODE (type) == FUNCTION_TYPE
8190 && type_quals != TYPE_UNQUALIFIED));
8192 /* Avoid setting TREE_READONLY incorrectly. */
8193 /* We used to check TYPE_NEEDS_CONSTRUCTING here, but now a constexpr
8194 constructor can produce constant init, so rely on cp_finish_decl to
8195 clear TREE_READONLY if the variable has non-constant init. */
8197 /* If the type has a mutable component, that component might be
8199 if (TYPE_HAS_MUTABLE_P (type))
8200 type_quals &= ~TYPE_QUAL_CONST;
8202 c_apply_type_quals_to_decl (type_quals, decl);
8205 /* Subroutine of casts_away_constness. Make T1 and T2 point at
8206 exemplar types such that casting T1 to T2 is casting away constness
8207 if and only if there is no implicit conversion from T1 to T2. */
8210 casts_away_constness_r (tree *t1, tree *t2)
8215 /* [expr.const.cast]
8217 For multi-level pointer to members and multi-level mixed pointers
8218 and pointers to members (conv.qual), the "member" aspect of a
8219 pointer to member level is ignored when determining if a const
8220 cv-qualifier has been cast away. */
8221 /* [expr.const.cast]
8223 For two pointer types:
8225 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
8226 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
8229 casting from X1 to X2 casts away constness if, for a non-pointer
8230 type T there does not exist an implicit conversion (clause
8233 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
8237 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
8238 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
8239 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
8241 *t1 = cp_build_qualified_type (void_type_node,
8242 cp_type_quals (*t1));
8243 *t2 = cp_build_qualified_type (void_type_node,
8244 cp_type_quals (*t2));
8248 quals1 = cp_type_quals (*t1);
8249 quals2 = cp_type_quals (*t2);
8251 if (TYPE_PTRMEM_P (*t1))
8252 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
8254 *t1 = TREE_TYPE (*t1);
8255 if (TYPE_PTRMEM_P (*t2))
8256 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
8258 *t2 = TREE_TYPE (*t2);
8260 casts_away_constness_r (t1, t2);
8261 *t1 = build_pointer_type (*t1);
8262 *t2 = build_pointer_type (*t2);
8263 *t1 = cp_build_qualified_type (*t1, quals1);
8264 *t2 = cp_build_qualified_type (*t2, quals2);
8267 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
8270 ??? This function returns non-zero if casting away qualifiers not
8271 just const. We would like to return to the caller exactly which
8272 qualifiers are casted away to give more accurate diagnostics.
8276 casts_away_constness (tree t1, tree t2)
8278 if (TREE_CODE (t2) == REFERENCE_TYPE)
8280 /* [expr.const.cast]
8282 Casting from an lvalue of type T1 to an lvalue of type T2
8283 using a reference cast casts away constness if a cast from an
8284 rvalue of type "pointer to T1" to the type "pointer to T2"
8285 casts away constness. */
8286 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
8287 return casts_away_constness (build_pointer_type (t1),
8288 build_pointer_type (TREE_TYPE (t2)));
8291 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
8292 /* [expr.const.cast]
8294 Casting from an rvalue of type "pointer to data member of X
8295 of type T1" to the type "pointer to data member of Y of type
8296 T2" casts away constness if a cast from an rvalue of type
8297 "pointer to T1" to the type "pointer to T2" casts away
8299 return casts_away_constness
8300 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
8301 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
8303 /* Casting away constness is only something that makes sense for
8304 pointer or reference types. */
8305 if (TREE_CODE (t1) != POINTER_TYPE
8306 || TREE_CODE (t2) != POINTER_TYPE)
8309 /* Top-level qualifiers don't matter. */
8310 t1 = TYPE_MAIN_VARIANT (t1);
8311 t2 = TYPE_MAIN_VARIANT (t2);
8312 casts_away_constness_r (&t1, &t2);
8313 if (!can_convert (t2, t1))
8319 /* If T is a REFERENCE_TYPE return the type to which T refers.
8320 Otherwise, return T itself. */
8323 non_reference (tree t)
8325 if (t && TREE_CODE (t) == REFERENCE_TYPE)
8331 /* Return nonzero if REF is an lvalue valid for this language;
8332 otherwise, print an error message and return zero. USE says
8333 how the lvalue is being used and so selects the error message. */
8336 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
8338 cp_lvalue_kind kind = lvalue_kind (ref);
8340 if (kind == clk_none)
8342 if (complain & tf_error)
8343 lvalue_error (input_location, use);
8346 else if (kind & (clk_rvalueref|clk_class))
8348 if (!(complain & tf_error))
8350 if (kind & clk_class)
8351 /* Make this a permerror because we used to accept it. */
8352 permerror (input_location, "using temporary as lvalue");
8354 error ("using xvalue (rvalue reference) as lvalue");