1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Hacked by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization. */
31 #include "coretypes.h"
41 #include "diagnostic.h"
48 static tree pfn_from_ptrmemfunc (tree);
49 static tree delta_from_ptrmemfunc (tree);
50 static tree convert_for_assignment (tree, tree, const char *, tree, int,
52 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
53 static tree rationalize_conditional_expr (enum tree_code, tree,
55 static int comp_ptr_ttypes_real (tree, tree, int);
56 static bool comp_except_types (tree, tree, bool);
57 static bool comp_array_types (const_tree, const_tree, bool);
58 static tree pointer_diff (tree, tree, tree);
59 static tree get_delta_difference (tree, tree, bool, bool);
60 static void casts_away_constness_r (tree *, tree *);
61 static bool casts_away_constness (tree, tree);
62 static void maybe_warn_about_returning_address_of_local (tree);
63 static tree lookup_destructor (tree, tree, tree);
64 static int convert_arguments (tree, VEC(tree,gc) **, tree, int,
67 /* Do `exp = require_complete_type (exp);' to make sure exp
68 does not have an incomplete type. (That includes void types.)
69 Returns the error_mark_node if the VALUE does not have
70 complete type when this function returns. */
73 require_complete_type (tree value)
77 if (processing_template_decl || value == error_mark_node)
80 if (TREE_CODE (value) == OVERLOAD)
81 type = unknown_type_node;
83 type = TREE_TYPE (value);
85 if (type == error_mark_node)
86 return error_mark_node;
88 /* First, detect a valid value with a complete type. */
89 if (COMPLETE_TYPE_P (type))
92 if (complete_type_or_else (type, value))
95 return error_mark_node;
98 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
99 a template instantiation, do the instantiation. Returns TYPE,
100 whether or not it could be completed, unless something goes
101 horribly wrong, in which case the error_mark_node is returned. */
104 complete_type (tree type)
106 if (type == NULL_TREE)
107 /* Rather than crash, we return something sure to cause an error
109 return error_mark_node;
111 if (type == error_mark_node || COMPLETE_TYPE_P (type))
113 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
115 tree t = complete_type (TREE_TYPE (type));
116 unsigned int needs_constructing, has_nontrivial_dtor;
117 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
120 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
122 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
123 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
125 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
126 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
129 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
130 instantiate_class_template (TYPE_MAIN_VARIANT (type));
135 /* Like complete_type, but issue an error if the TYPE cannot be completed.
136 VALUE is used for informative diagnostics.
137 Returns NULL_TREE if the type cannot be made complete. */
140 complete_type_or_else (tree type, tree value)
142 type = complete_type (type);
143 if (type == error_mark_node)
144 /* We already issued an error. */
146 else if (!COMPLETE_TYPE_P (type))
148 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
155 /* Return truthvalue of whether type of EXP is instantiated. */
158 type_unknown_p (const_tree exp)
160 return (TREE_CODE (exp) == TREE_LIST
161 || TREE_TYPE (exp) == unknown_type_node);
165 /* Return the common type of two parameter lists.
166 We assume that comptypes has already been done and returned 1;
167 if that isn't so, this may crash.
169 As an optimization, free the space we allocate if the parameter
170 lists are already common. */
173 commonparms (tree p1, tree p2)
175 tree oldargs = p1, newargs, n;
179 len = list_length (p1);
180 newargs = tree_last (p1);
182 if (newargs == void_list_node)
191 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
196 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
198 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
200 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
203 else if (! TREE_PURPOSE (p1))
205 if (TREE_PURPOSE (p2))
207 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
213 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
215 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
217 if (TREE_VALUE (p1) != TREE_VALUE (p2))
220 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
223 TREE_VALUE (n) = TREE_VALUE (p1);
231 /* Given a type, perhaps copied for a typedef,
232 find the "original" version of it. */
234 original_type (tree t)
236 int quals = cp_type_quals (t);
237 while (t != error_mark_node
238 && TYPE_NAME (t) != NULL_TREE)
240 tree x = TYPE_NAME (t);
241 if (TREE_CODE (x) != TYPE_DECL)
243 x = DECL_ORIGINAL_TYPE (x);
248 return cp_build_qualified_type (t, quals);
251 /* Return the common type for two arithmetic types T1 and T2 under the
252 usual arithmetic conversions. The default conversions have already
253 been applied, and enumerated types converted to their compatible
257 cp_common_type (tree t1, tree t2)
259 enum tree_code code1 = TREE_CODE (t1);
260 enum tree_code code2 = TREE_CODE (t2);
263 /* In what follows, we slightly generalize the rules given in [expr] so
264 as to deal with `long long' and `complex'. First, merge the
266 attributes = (*targetm.merge_type_attributes) (t1, t2);
268 if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2))
270 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
271 return build_type_attribute_variant (t1, attributes);
276 /* FIXME: Attributes. */
277 gcc_assert (ARITHMETIC_TYPE_P (t1)
278 || TREE_CODE (t1) == VECTOR_TYPE
279 || UNSCOPED_ENUM_P (t1));
280 gcc_assert (ARITHMETIC_TYPE_P (t2)
281 || TREE_CODE (t2) == VECTOR_TYPE
282 || UNSCOPED_ENUM_P (t2));
284 /* If one type is complex, form the common type of the non-complex
285 components, then make that complex. Use T1 or T2 if it is the
287 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
289 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
290 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
292 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
294 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
295 return build_type_attribute_variant (t1, attributes);
296 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
297 return build_type_attribute_variant (t2, attributes);
299 return build_type_attribute_variant (build_complex_type (subtype),
303 if (code1 == VECTOR_TYPE)
305 /* When we get here we should have two vectors of the same size.
306 Just prefer the unsigned one if present. */
307 if (TYPE_UNSIGNED (t1))
308 return build_type_attribute_variant (t1, attributes);
310 return build_type_attribute_variant (t2, attributes);
313 /* If only one is real, use it as the result. */
314 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
315 return build_type_attribute_variant (t1, attributes);
316 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
317 return build_type_attribute_variant (t2, attributes);
319 /* Both real or both integers; use the one with greater precision. */
320 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
321 return build_type_attribute_variant (t1, attributes);
322 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
323 return build_type_attribute_variant (t2, attributes);
325 /* The types are the same; no need to do anything fancy. */
326 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
327 return build_type_attribute_variant (t1, attributes);
329 if (code1 != REAL_TYPE)
331 /* If one is unsigned long long, then convert the other to unsigned
333 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
334 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
335 return build_type_attribute_variant (long_long_unsigned_type_node,
337 /* If one is a long long, and the other is an unsigned long, and
338 long long can represent all the values of an unsigned long, then
339 convert to a long long. Otherwise, convert to an unsigned long
340 long. Otherwise, if either operand is long long, convert the
343 Since we're here, we know the TYPE_PRECISION is the same;
344 therefore converting to long long cannot represent all the values
345 of an unsigned long, so we choose unsigned long long in that
347 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
348 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
350 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
351 ? long_long_unsigned_type_node
352 : long_long_integer_type_node);
353 return build_type_attribute_variant (t, attributes);
356 /* Go through the same procedure, but for longs. */
357 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
358 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
359 return build_type_attribute_variant (long_unsigned_type_node,
361 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
362 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
364 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
365 ? long_unsigned_type_node : long_integer_type_node);
366 return build_type_attribute_variant (t, attributes);
368 /* Otherwise prefer the unsigned one. */
369 if (TYPE_UNSIGNED (t1))
370 return build_type_attribute_variant (t1, attributes);
372 return build_type_attribute_variant (t2, attributes);
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
378 return build_type_attribute_variant (long_double_type_node,
380 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
381 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
382 return build_type_attribute_variant (double_type_node,
384 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
386 return build_type_attribute_variant (float_type_node,
389 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
390 the standard C++ floating-point types. Logic earlier in this
391 function has already eliminated the possibility that
392 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
393 compelling reason to choose one or the other. */
394 return build_type_attribute_variant (t1, attributes);
398 /* T1 and T2 are arithmetic or enumeration types. Return the type
399 that will result from the "usual arithmetic conversions" on T1 and
400 T2 as described in [expr]. */
403 type_after_usual_arithmetic_conversions (tree t1, tree t2)
405 gcc_assert (ARITHMETIC_TYPE_P (t1)
406 || TREE_CODE (t1) == VECTOR_TYPE
407 || UNSCOPED_ENUM_P (t1));
408 gcc_assert (ARITHMETIC_TYPE_P (t2)
409 || TREE_CODE (t2) == VECTOR_TYPE
410 || UNSCOPED_ENUM_P (t2));
412 /* Perform the integral promotions. We do not promote real types here. */
413 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
414 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
416 t1 = type_promotes_to (t1);
417 t2 = type_promotes_to (t2);
420 return cp_common_type (t1, t2);
423 /* Subroutine of composite_pointer_type to implement the recursive
424 case. See that function for documentation fo the parameters. */
427 composite_pointer_type_r (tree t1, tree t2, const char* location,
428 tsubst_flags_t complain)
435 /* Determine the types pointed to by T1 and T2. */
436 if (TREE_CODE (t1) == POINTER_TYPE)
438 pointee1 = TREE_TYPE (t1);
439 pointee2 = TREE_TYPE (t2);
443 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
444 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
449 Otherwise, the composite pointer type is a pointer type
450 similar (_conv.qual_) to the type of one of the operands,
451 with a cv-qualification signature (_conv.qual_) that is the
452 union of the cv-qualification signatures of the operand
454 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
455 result_type = pointee1;
456 else if ((TREE_CODE (pointee1) == POINTER_TYPE
457 && TREE_CODE (pointee2) == POINTER_TYPE)
458 || (TYPE_PTR_TO_MEMBER_P (pointee1)
459 && TYPE_PTR_TO_MEMBER_P (pointee2)))
460 result_type = composite_pointer_type_r (pointee1, pointee2, location,
464 if (complain & tf_error)
465 permerror (input_location, "%s between distinct pointer types %qT and %qT "
468 result_type = void_type_node;
470 result_type = cp_build_qualified_type (result_type,
471 (cp_type_quals (pointee1)
472 | cp_type_quals (pointee2)));
473 /* If the original types were pointers to members, so is the
475 if (TYPE_PTR_TO_MEMBER_P (t1))
477 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
478 TYPE_PTRMEM_CLASS_TYPE (t2))
479 && (complain & tf_error))
480 permerror (input_location, "%s between distinct pointer types %qT and %qT "
483 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
487 result_type = build_pointer_type (result_type);
489 /* Merge the attributes. */
490 attributes = (*targetm.merge_type_attributes) (t1, t2);
491 return build_type_attribute_variant (result_type, attributes);
494 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
495 ARG1 and ARG2 are the values with those types. The LOCATION is a
496 string describing the current location, in case an error occurs.
498 This routine also implements the computation of a common type for
499 pointers-to-members as per [expr.eq]. */
502 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
503 const char* location, tsubst_flags_t complain)
510 If one operand is a null pointer constant, the composite pointer
511 type is the type of the other operand. */
512 if (null_ptr_cst_p (arg1))
514 if (null_ptr_cst_p (arg2))
521 If one of the operands has type "pointer to cv1 void*", then
522 the other has type "pointer to cv2T", and the composite pointer
523 type is "pointer to cv12 void", where cv12 is the union of cv1
526 If either type is a pointer to void, make sure it is T1. */
527 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
535 /* Now, if T1 is a pointer to void, merge the qualifiers. */
536 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
541 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
542 pedwarn (input_location, OPT_pedantic, "ISO C++ forbids %s "
543 "between pointer of type %<void *%> and pointer-to-function",
546 = cp_build_qualified_type (void_type_node,
547 (cp_type_quals (TREE_TYPE (t1))
548 | cp_type_quals (TREE_TYPE (t2))));
549 result_type = build_pointer_type (result_type);
550 /* Merge the attributes. */
551 attributes = (*targetm.merge_type_attributes) (t1, t2);
552 return build_type_attribute_variant (result_type, attributes);
555 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
556 && TREE_CODE (t2) == POINTER_TYPE)
558 if (objc_compare_types (t1, t2, -3, NULL_TREE))
562 /* [expr.eq] permits the application of a pointer conversion to
563 bring the pointers to a common type. */
564 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
565 && CLASS_TYPE_P (TREE_TYPE (t1))
566 && CLASS_TYPE_P (TREE_TYPE (t2))
567 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
570 class1 = TREE_TYPE (t1);
571 class2 = TREE_TYPE (t2);
573 if (DERIVED_FROM_P (class1, class2))
574 t2 = (build_pointer_type
575 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
576 else if (DERIVED_FROM_P (class2, class1))
577 t1 = (build_pointer_type
578 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
581 if (complain & tf_error)
582 error ("%s between distinct pointer types %qT and %qT "
583 "lacks a cast", location, t1, t2);
584 return error_mark_node;
587 /* [expr.eq] permits the application of a pointer-to-member
588 conversion to change the class type of one of the types. */
589 else if (TYPE_PTR_TO_MEMBER_P (t1)
590 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
591 TYPE_PTRMEM_CLASS_TYPE (t2)))
593 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
594 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
596 if (DERIVED_FROM_P (class1, class2))
597 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
598 else if (DERIVED_FROM_P (class2, class1))
599 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
602 if (complain & tf_error)
603 error ("%s between distinct pointer-to-member types %qT and %qT "
604 "lacks a cast", location, t1, t2);
605 return error_mark_node;
609 return composite_pointer_type_r (t1, t2, location, complain);
612 /* Return the merged type of two types.
613 We assume that comptypes has already been done and returned 1;
614 if that isn't so, this may crash.
616 This just combines attributes and default arguments; any other
617 differences would cause the two types to compare unalike. */
620 merge_types (tree t1, tree t2)
622 enum tree_code code1;
623 enum tree_code code2;
626 /* Save time if the two types are the same. */
629 if (original_type (t1) == original_type (t2))
632 /* If one type is nonsense, use the other. */
633 if (t1 == error_mark_node)
635 if (t2 == error_mark_node)
638 /* Merge the attributes. */
639 attributes = (*targetm.merge_type_attributes) (t1, t2);
641 if (TYPE_PTRMEMFUNC_P (t1))
642 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
643 if (TYPE_PTRMEMFUNC_P (t2))
644 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
646 code1 = TREE_CODE (t1);
647 code2 = TREE_CODE (t2);
650 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
651 if (code1 == TYPENAME_TYPE)
653 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
654 code1 = TREE_CODE (t1);
658 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
659 code2 = TREE_CODE (t2);
667 /* For two pointers, do this recursively on the target type. */
669 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
670 int quals = cp_type_quals (t1);
672 if (code1 == POINTER_TYPE)
673 t1 = build_pointer_type (target);
675 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
676 t1 = build_type_attribute_variant (t1, attributes);
677 t1 = cp_build_qualified_type (t1, quals);
679 if (TREE_CODE (target) == METHOD_TYPE)
680 t1 = build_ptrmemfunc_type (t1);
689 quals = cp_type_quals (t1);
690 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
691 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
692 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
694 t1 = cp_build_qualified_type (t1, quals);
700 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
701 /* Save space: see if the result is identical to one of the args. */
702 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
703 return build_type_attribute_variant (t1, attributes);
704 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
705 return build_type_attribute_variant (t2, attributes);
706 /* Merge the element types, and have a size if either arg has one. */
707 t1 = build_cplus_array_type
708 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
713 /* Function types: prefer the one that specified arg types.
714 If both do, merge the arg types. Also merge the return types. */
716 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
717 tree p1 = TYPE_ARG_TYPES (t1);
718 tree p2 = TYPE_ARG_TYPES (t2);
721 /* Save space: see if the result is identical to one of the args. */
722 if (valtype == TREE_TYPE (t1) && ! p2)
723 return cp_build_type_attribute_variant (t1, attributes);
724 if (valtype == TREE_TYPE (t2) && ! p1)
725 return cp_build_type_attribute_variant (t2, attributes);
727 /* Simple way if one arg fails to specify argument types. */
728 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
730 rval = build_function_type (valtype, p2);
731 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
732 rval = build_exception_variant (rval, raises);
733 return cp_build_type_attribute_variant (rval, attributes);
735 raises = TYPE_RAISES_EXCEPTIONS (t1);
736 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
738 rval = build_function_type (valtype, p1);
740 rval = build_exception_variant (rval, raises);
741 return cp_build_type_attribute_variant (rval, attributes);
744 rval = build_function_type (valtype, commonparms (p1, p2));
745 t1 = build_exception_variant (rval, raises);
751 /* Get this value the long way, since TYPE_METHOD_BASETYPE
752 is just the main variant of this. */
753 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
754 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
757 /* If this was a member function type, get back to the
758 original type of type member function (i.e., without
759 the class instance variable up front. */
760 t1 = build_function_type (TREE_TYPE (t1),
761 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
762 t2 = build_function_type (TREE_TYPE (t2),
763 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
764 t3 = merge_types (t1, t2);
765 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
766 TYPE_ARG_TYPES (t3));
767 t1 = build_exception_variant (t3, raises);
772 /* There is no need to merge attributes into a TYPENAME_TYPE.
773 When the type is instantiated it will have whatever
774 attributes result from the instantiation. */
780 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
782 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
785 return cp_build_type_attribute_variant (t1, attributes);
788 /* Wrapper around cp_common_type that is used by c-common.c and other
789 front end optimizations that remove promotions.
791 Return the common type for two arithmetic types T1 and T2 under the
792 usual arithmetic conversions. The default conversions have already
793 been applied, and enumerated types converted to their compatible
797 common_type (tree t1, tree t2)
799 /* If one type is nonsense, use the other */
800 if (t1 == error_mark_node)
802 if (t2 == error_mark_node)
805 return cp_common_type (t1, t2);
808 /* Return the common type of two pointer types T1 and T2. This is the
809 type for the result of most arithmetic operations if the operands
810 have the given two types.
812 We assume that comp_target_types has already been done and returned
813 nonzero; if that isn't so, this may crash. */
816 common_pointer_type (tree t1, tree t2)
818 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
819 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
820 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
822 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
823 "conversion", tf_warning_or_error);
826 /* Compare two exception specifier types for exactness or subsetness, if
827 allowed. Returns false for mismatch, true for match (same, or
830 [except.spec] "If a class X ... objects of class X or any class publicly
831 and unambiguously derived from X. Similarly, if a pointer type Y * ...
832 exceptions of type Y * or that are pointers to any type publicly and
833 unambiguously derived from Y. Otherwise a function only allows exceptions
834 that have the same type ..."
835 This does not mention cv qualifiers and is different to what throw
836 [except.throw] and catch [except.catch] will do. They will ignore the
837 top level cv qualifiers, and allow qualifiers in the pointer to class
840 We implement the letter of the standard. */
843 comp_except_types (tree a, tree b, bool exact)
845 if (same_type_p (a, b))
849 if (cp_type_quals (a) || cp_type_quals (b))
852 if (TREE_CODE (a) == POINTER_TYPE
853 && TREE_CODE (b) == POINTER_TYPE)
857 if (cp_type_quals (a) || cp_type_quals (b))
861 if (TREE_CODE (a) != RECORD_TYPE
862 || TREE_CODE (b) != RECORD_TYPE)
865 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
871 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
872 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
873 otherwise it must be exact. Exception lists are unordered, but
874 we've already filtered out duplicates. Most lists will be in order,
875 we should try to make use of that. */
878 comp_except_specs (const_tree t1, const_tree t2, bool exact)
887 if (t1 == NULL_TREE) /* T1 is ... */
888 return t2 == NULL_TREE || !exact;
889 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
890 return t2 != NULL_TREE && !TREE_VALUE (t2);
891 if (t2 == NULL_TREE) /* T2 is ... */
893 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
896 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
897 Count how many we find, to determine exactness. For exact matching and
898 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
900 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
902 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
904 tree a = TREE_VALUE (probe);
905 tree b = TREE_VALUE (t2);
907 if (comp_except_types (a, b, exact))
909 if (probe == base && exact)
910 base = TREE_CHAIN (probe);
915 if (probe == NULL_TREE)
918 return !exact || base == NULL_TREE || length == list_length (t1);
921 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
922 [] can match [size]. */
925 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
934 /* The type of the array elements must be the same. */
935 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
938 d1 = TYPE_DOMAIN (t1);
939 d2 = TYPE_DOMAIN (t2);
944 /* If one of the arrays is dimensionless, and the other has a
945 dimension, they are of different types. However, it is valid to
953 declarations for an array object can specify
954 array types that differ by the presence or absence of a major
955 array bound (_dcl.array_). */
957 return allow_redeclaration;
959 /* Check that the dimensions are the same. */
961 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
963 max1 = TYPE_MAX_VALUE (d1);
964 max2 = TYPE_MAX_VALUE (d2);
965 if (processing_template_decl && !abi_version_at_least (2)
966 && !value_dependent_expression_p (max1)
967 && !value_dependent_expression_p (max2))
969 /* With abi-1 we do not fold non-dependent array bounds, (and
970 consequently mangle them incorrectly). We must therefore
971 fold them here, to verify the domains have the same
977 if (!cp_tree_equal (max1, max2))
983 /* Subroutine in comptypes. */
986 structural_comptypes (tree t1, tree t2, int strict)
991 /* Suppress errors caused by previously reported errors. */
992 if (t1 == error_mark_node || t2 == error_mark_node)
995 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
997 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
998 current instantiation. */
999 if (TREE_CODE (t1) == TYPENAME_TYPE)
1000 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1002 if (TREE_CODE (t2) == TYPENAME_TYPE)
1003 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1005 if (TYPE_PTRMEMFUNC_P (t1))
1006 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1007 if (TYPE_PTRMEMFUNC_P (t2))
1008 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1010 /* Different classes of types can't be compatible. */
1011 if (TREE_CODE (t1) != TREE_CODE (t2))
1014 /* Qualifiers must match. For array types, we will check when we
1015 recur on the array element types. */
1016 if (TREE_CODE (t1) != ARRAY_TYPE
1017 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
1019 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1022 /* Allow for two different type nodes which have essentially the same
1023 definition. Note that we already checked for equality of the type
1024 qualifiers (just above). */
1026 if (TREE_CODE (t1) != ARRAY_TYPE
1027 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1030 /* Compare the types. Break out if they could be the same. */
1031 switch (TREE_CODE (t1))
1035 /* All void and bool types are the same. */
1039 case FIXED_POINT_TYPE:
1041 /* With these nodes, we can't determine type equivalence by
1042 looking at what is stored in the nodes themselves, because
1043 two nodes might have different TYPE_MAIN_VARIANTs but still
1044 represent the same type. For example, wchar_t and int could
1045 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1046 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1047 and are distinct types. On the other hand, int and the
1050 typedef int INT __attribute((may_alias));
1052 have identical properties, different TYPE_MAIN_VARIANTs, but
1053 represent the same type. The canonical type system keeps
1054 track of equivalence in this case, so we fall back on it. */
1055 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1057 case TEMPLATE_TEMPLATE_PARM:
1058 case BOUND_TEMPLATE_TEMPLATE_PARM:
1059 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1060 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1061 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1062 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1066 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1068 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1070 /* Don't check inheritance. */
1071 strict = COMPARE_STRICT;
1076 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1077 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1078 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1079 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1082 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1084 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1090 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1091 strict & ~COMPARE_REDECLARATION))
1093 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1097 case REFERENCE_TYPE:
1098 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1100 /* fall through to checks for pointer types */
1103 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1104 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1105 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1111 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1113 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1118 /* Target types must match incl. qualifiers. */
1119 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1123 case TEMPLATE_TYPE_PARM:
1124 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1125 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1126 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1127 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1132 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1133 TYPENAME_TYPE_FULLNAME (t2)))
1135 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1139 case UNBOUND_CLASS_TEMPLATE:
1140 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1142 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1147 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1152 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1153 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1157 case TYPE_PACK_EXPANSION:
1158 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1159 PACK_EXPANSION_PATTERN (t2));
1162 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1163 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1164 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1165 DECLTYPE_TYPE_EXPR (t2)))
1173 /* If we get here, we know that from a target independent POV the
1174 types are the same. Make sure the target attributes are also
1176 return targetm.comp_type_attributes (t1, t2);
1179 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1180 is a bitwise-or of the COMPARE_* flags. */
1183 comptypes (tree t1, tree t2, int strict)
1185 if (strict == COMPARE_STRICT)
1190 if (t1 == error_mark_node || t2 == error_mark_node)
1193 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1194 /* At least one of the types requires structural equality, so
1195 perform a deep check. */
1196 return structural_comptypes (t1, t2, strict);
1198 #ifdef ENABLE_CHECKING
1199 if (USE_CANONICAL_TYPES)
1201 bool result = structural_comptypes (t1, t2, strict);
1203 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1204 /* The two types are structurally equivalent, but their
1205 canonical types were different. This is a failure of the
1206 canonical type propagation code.*/
1208 ("canonical types differ for identical types %T and %T",
1210 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1211 /* Two types are structurally different, but the canonical
1212 types are the same. This means we were over-eager in
1213 assigning canonical types. */
1215 ("same canonical type node for different types %T and %T",
1221 if (USE_CANONICAL_TYPES)
1222 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1225 return structural_comptypes (t1, t2, strict);
1227 else if (strict == COMPARE_STRUCTURAL)
1228 return structural_comptypes (t1, t2, COMPARE_STRICT);
1230 return structural_comptypes (t1, t2, strict);
1233 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1236 at_least_as_qualified_p (const_tree type1, const_tree type2)
1238 int q1 = cp_type_quals (type1);
1239 int q2 = cp_type_quals (type2);
1241 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1242 return (q1 & q2) == q2;
1245 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1246 more cv-qualified that TYPE1, and 0 otherwise. */
1249 comp_cv_qualification (const_tree type1, const_tree type2)
1251 int q1 = cp_type_quals (type1);
1252 int q2 = cp_type_quals (type2);
1257 if ((q1 & q2) == q2)
1259 else if ((q1 & q2) == q1)
1265 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1266 subset of the cv-qualification signature of TYPE2, and the types
1267 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1270 comp_cv_qual_signature (tree type1, tree type2)
1272 if (comp_ptr_ttypes_real (type2, type1, -1))
1274 else if (comp_ptr_ttypes_real (type1, type2, -1))
1280 /* Subroutines of `comptypes'. */
1282 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1283 equivalent in the sense that functions with those parameter types
1284 can have equivalent types. The two lists must be equivalent,
1285 element by element. */
1288 compparms (const_tree parms1, const_tree parms2)
1292 /* An unspecified parmlist matches any specified parmlist
1293 whose argument types don't need default promotions. */
1295 for (t1 = parms1, t2 = parms2;
1297 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1299 /* If one parmlist is shorter than the other,
1300 they fail to match. */
1303 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1310 /* Process a sizeof or alignof expression where the operand is a
1314 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1319 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1320 if (type == error_mark_node)
1321 return error_mark_node;
1323 type = non_reference (type);
1324 if (TREE_CODE (type) == METHOD_TYPE)
1327 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1328 "invalid application of %qs to a member function",
1329 operator_name_info[(int) op].name);
1330 value = size_one_node;
1333 dependent_p = dependent_type_p (type);
1335 complete_type (type);
1337 /* VLA types will have a non-constant size. In the body of an
1338 uninstantiated template, we don't need to try to compute the
1339 value, because the sizeof expression is not an integral
1340 constant expression in that case. And, if we do try to
1341 compute the value, we'll likely end up with SAVE_EXPRs, which
1342 the template substitution machinery does not expect to see. */
1343 || (processing_template_decl
1344 && COMPLETE_TYPE_P (type)
1345 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1347 value = build_min (op, size_type_node, type);
1348 TREE_READONLY (value) = 1;
1352 return c_sizeof_or_alignof_type (complete_type (type),
1357 /* Return the size of the type, without producing any warnings for
1358 types whose size cannot be taken. This routine should be used only
1359 in some other routine that has already produced a diagnostic about
1360 using the size of such a type. */
1362 cxx_sizeof_nowarn (tree type)
1364 if (TREE_CODE (type) == FUNCTION_TYPE
1365 || TREE_CODE (type) == VOID_TYPE
1366 || TREE_CODE (type) == ERROR_MARK)
1367 return size_one_node;
1368 else if (!COMPLETE_TYPE_P (type))
1369 return size_zero_node;
1371 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1374 /* Process a sizeof expression where the operand is an expression. */
1377 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1379 if (e == error_mark_node)
1380 return error_mark_node;
1382 if (processing_template_decl)
1384 e = build_min (SIZEOF_EXPR, size_type_node, e);
1385 TREE_SIDE_EFFECTS (e) = 0;
1386 TREE_READONLY (e) = 1;
1391 if (TREE_CODE (e) == COMPONENT_REF
1392 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1393 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1395 if (complain & tf_error)
1396 error ("invalid application of %<sizeof%> to a bit-field");
1398 return error_mark_node;
1401 else if (is_overloaded_fn (e))
1403 if (complain & tf_error)
1404 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1407 return error_mark_node;
1410 else if (type_unknown_p (e))
1412 if (complain & tf_error)
1413 cxx_incomplete_type_error (e, TREE_TYPE (e));
1415 return error_mark_node;
1421 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1424 /* Implement the __alignof keyword: Return the minimum required
1425 alignment of E, measured in bytes. For VAR_DECL's and
1426 FIELD_DECL's return DECL_ALIGN (which can be set from an
1427 "aligned" __attribute__ specification). */
1430 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1434 if (e == error_mark_node)
1435 return error_mark_node;
1437 if (processing_template_decl)
1439 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1440 TREE_SIDE_EFFECTS (e) = 0;
1441 TREE_READONLY (e) = 1;
1446 if (TREE_CODE (e) == VAR_DECL)
1447 t = size_int (DECL_ALIGN_UNIT (e));
1448 else if (TREE_CODE (e) == COMPONENT_REF
1449 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1450 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1452 if (complain & tf_error)
1453 error ("invalid application of %<__alignof%> to a bit-field");
1455 return error_mark_node;
1458 else if (TREE_CODE (e) == COMPONENT_REF
1459 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1460 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1461 else if (is_overloaded_fn (e))
1463 if (complain & tf_error)
1464 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1467 return error_mark_node;
1468 if (TREE_CODE (e) == FUNCTION_DECL)
1469 t = size_int (DECL_ALIGN_UNIT (e));
1473 else if (type_unknown_p (e))
1475 if (complain & tf_error)
1476 cxx_incomplete_type_error (e, TREE_TYPE (e));
1478 return error_mark_node;
1482 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1483 complain & tf_error);
1485 return fold_convert (size_type_node, t);
1488 /* Process a sizeof or alignof expression E with code OP where the operand
1489 is an expression. */
1492 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1494 if (op == SIZEOF_EXPR)
1495 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1497 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1500 /* EXPR is being used in a context that is not a function call.
1505 The expression can be used only as the left-hand operand of a
1506 member function call.
1508 [expr.mptr.operator]
1510 If the result of .* or ->* is a function, then that result can be
1511 used only as the operand for the function call operator ().
1513 by issuing an error message if appropriate. Returns true iff EXPR
1514 violates these rules. */
1517 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1519 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1521 if (complain & tf_error)
1522 error ("invalid use of non-static member function");
1528 /* If EXP is a reference to a bitfield, and the type of EXP does not
1529 match the declared type of the bitfield, return the declared type
1530 of the bitfield. Otherwise, return NULL_TREE. */
1533 is_bitfield_expr_with_lowered_type (const_tree exp)
1535 switch (TREE_CODE (exp))
1538 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1539 ? TREE_OPERAND (exp, 1)
1540 : TREE_OPERAND (exp, 0)))
1542 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1545 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1549 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1555 field = TREE_OPERAND (exp, 1);
1556 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1558 if (same_type_ignoring_top_level_qualifiers_p
1559 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1561 return DECL_BIT_FIELD_TYPE (field);
1565 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1566 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1567 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1575 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1576 bitfield with a lowered type, the type of EXP is returned, rather
1580 unlowered_expr_type (const_tree exp)
1584 type = is_bitfield_expr_with_lowered_type (exp);
1586 type = TREE_TYPE (exp);
1591 /* Perform the conversions in [expr] that apply when an lvalue appears
1592 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1593 function-to-pointer conversions. In addition, manifest constants
1594 are replaced by their values, and bitfield references are converted
1595 to their declared types.
1597 Although the returned value is being used as an rvalue, this
1598 function does not wrap the returned expression in a
1599 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1600 that the return value is no longer an lvalue. */
1603 decay_conversion (tree exp)
1606 enum tree_code code;
1608 type = TREE_TYPE (exp);
1609 if (type == error_mark_node)
1610 return error_mark_node;
1612 if (type_unknown_p (exp))
1614 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1615 return error_mark_node;
1618 exp = decl_constant_value (exp);
1619 if (error_operand_p (exp))
1620 return error_mark_node;
1622 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1623 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1624 code = TREE_CODE (type);
1625 if (code == VOID_TYPE)
1627 error ("void value not ignored as it ought to be");
1628 return error_mark_node;
1630 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1631 return error_mark_node;
1632 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1633 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1634 if (code == ARRAY_TYPE)
1639 if (TREE_CODE (exp) == INDIRECT_REF)
1640 return build_nop (build_pointer_type (TREE_TYPE (type)),
1641 TREE_OPERAND (exp, 0));
1643 if (TREE_CODE (exp) == COMPOUND_EXPR)
1645 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1646 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1647 TREE_OPERAND (exp, 0), op1);
1651 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1653 error ("invalid use of non-lvalue array");
1654 return error_mark_node;
1657 ptrtype = build_pointer_type (TREE_TYPE (type));
1659 if (TREE_CODE (exp) == VAR_DECL)
1661 if (!cxx_mark_addressable (exp))
1662 return error_mark_node;
1663 adr = build_nop (ptrtype, build_address (exp));
1666 /* This way is better for a COMPONENT_REF since it can
1667 simplify the offset for a component. */
1668 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1669 return cp_convert (ptrtype, adr);
1672 /* If a bitfield is used in a context where integral promotion
1673 applies, then the caller is expected to have used
1674 default_conversion. That function promotes bitfields correctly
1675 before calling this function. At this point, if we have a
1676 bitfield referenced, we may assume that is not subject to
1677 promotion, and that, therefore, the type of the resulting rvalue
1678 is the declared type of the bitfield. */
1679 exp = convert_bitfield_to_declared_type (exp);
1681 /* We do not call rvalue() here because we do not want to wrap EXP
1682 in a NON_LVALUE_EXPR. */
1686 Non-class rvalues always have cv-unqualified types. */
1687 type = TREE_TYPE (exp);
1688 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1689 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1694 /* Perform preparatory conversions, as part of the "usual arithmetic
1695 conversions". In particular, as per [expr]:
1697 Whenever an lvalue expression appears as an operand of an
1698 operator that expects the rvalue for that operand, the
1699 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1700 standard conversions are applied to convert the expression to an
1703 In addition, we perform integral promotions here, as those are
1704 applied to both operands to a binary operator before determining
1705 what additional conversions should apply. */
1708 default_conversion (tree exp)
1710 /* Check for target-specific promotions. */
1711 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
1713 exp = cp_convert (promoted_type, exp);
1714 /* Perform the integral promotions first so that bitfield
1715 expressions (which may promote to "int", even if the bitfield is
1716 declared "unsigned") are promoted correctly. */
1717 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1718 exp = perform_integral_promotions (exp);
1719 /* Perform the other conversions. */
1720 exp = decay_conversion (exp);
1725 /* EXPR is an expression with an integral or enumeration type.
1726 Perform the integral promotions in [conv.prom], and return the
1730 perform_integral_promotions (tree expr)
1737 If the bitfield has an enumerated type, it is treated as any
1738 other value of that type for promotion purposes. */
1739 type = is_bitfield_expr_with_lowered_type (expr);
1740 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1741 type = TREE_TYPE (expr);
1742 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1743 promoted_type = type_promotes_to (type);
1744 if (type != promoted_type)
1745 expr = cp_convert (promoted_type, expr);
1749 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1750 decay_conversion to one. */
1753 string_conv_p (const_tree totype, const_tree exp, int warn)
1757 if (TREE_CODE (totype) != POINTER_TYPE)
1760 t = TREE_TYPE (totype);
1761 if (!same_type_p (t, char_type_node)
1762 && !same_type_p (t, char16_type_node)
1763 && !same_type_p (t, char32_type_node)
1764 && !same_type_p (t, wchar_type_node))
1767 if (TREE_CODE (exp) == STRING_CST)
1769 /* Make sure that we don't try to convert between char and wide chars. */
1770 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1775 /* Is this a string constant which has decayed to 'const char *'? */
1776 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1777 if (!same_type_p (TREE_TYPE (exp), t))
1780 if (TREE_CODE (exp) != ADDR_EXPR
1781 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1785 /* This warning is not very useful, as it complains about printf. */
1787 warning (OPT_Wwrite_strings,
1788 "deprecated conversion from string constant to %qT",
1794 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1795 can, for example, use as an lvalue. This code used to be in
1796 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1797 expressions, where we're dealing with aggregates. But now it's again only
1798 called from unary_complex_lvalue. The case (in particular) that led to
1799 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1803 rationalize_conditional_expr (enum tree_code code, tree t,
1804 tsubst_flags_t complain)
1806 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1807 the first operand is always the one to be used if both operands
1808 are equal, so we know what conditional expression this used to be. */
1809 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1811 tree op0 = TREE_OPERAND (t, 0);
1812 tree op1 = TREE_OPERAND (t, 1);
1814 /* The following code is incorrect if either operand side-effects. */
1815 gcc_assert (!TREE_SIDE_EFFECTS (op0)
1816 && !TREE_SIDE_EFFECTS (op1));
1818 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1819 ? LE_EXPR : GE_EXPR),
1820 op0, TREE_CODE (op0),
1821 op1, TREE_CODE (op1),
1822 /*overloaded_p=*/NULL,
1824 cp_build_unary_op (code, op0, 0, complain),
1825 cp_build_unary_op (code, op1, 0, complain),
1830 build_conditional_expr (TREE_OPERAND (t, 0),
1831 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
1833 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
1838 /* Given the TYPE of an anonymous union field inside T, return the
1839 FIELD_DECL for the field. If not found return NULL_TREE. Because
1840 anonymous unions can nest, we must also search all anonymous unions
1841 that are directly reachable. */
1844 lookup_anon_field (tree t, tree type)
1848 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1850 if (TREE_STATIC (field))
1852 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1855 /* If we find it directly, return the field. */
1856 if (DECL_NAME (field) == NULL_TREE
1857 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1862 /* Otherwise, it could be nested, search harder. */
1863 if (DECL_NAME (field) == NULL_TREE
1864 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1866 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1874 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1875 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1876 non-NULL, it indicates the path to the base used to name MEMBER.
1877 If PRESERVE_REFERENCE is true, the expression returned will have
1878 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1879 returned will have the type referred to by the reference.
1881 This function does not perform access control; that is either done
1882 earlier by the parser when the name of MEMBER is resolved to MEMBER
1883 itself, or later when overload resolution selects one of the
1884 functions indicated by MEMBER. */
1887 build_class_member_access_expr (tree object, tree member,
1888 tree access_path, bool preserve_reference,
1889 tsubst_flags_t complain)
1893 tree result = NULL_TREE;
1895 if (error_operand_p (object) || error_operand_p (member))
1896 return error_mark_node;
1898 gcc_assert (DECL_P (member) || BASELINK_P (member));
1902 The type of the first expression shall be "class object" (of a
1904 object_type = TREE_TYPE (object);
1905 if (!currently_open_class (object_type)
1906 && !complete_type_or_else (object_type, object))
1907 return error_mark_node;
1908 if (!CLASS_TYPE_P (object_type))
1910 if (complain & tf_error)
1911 error ("request for member %qD in %qE, which is of non-class type %qT",
1912 member, object, object_type);
1913 return error_mark_node;
1916 /* The standard does not seem to actually say that MEMBER must be a
1917 member of OBJECT_TYPE. However, that is clearly what is
1919 if (DECL_P (member))
1921 member_scope = DECL_CLASS_CONTEXT (member);
1923 if (TREE_DEPRECATED (member))
1924 warn_deprecated_use (member, NULL_TREE);
1927 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
1928 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1929 presently be the anonymous union. Go outwards until we find a
1930 type related to OBJECT_TYPE. */
1931 while (ANON_AGGR_TYPE_P (member_scope)
1932 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1934 member_scope = TYPE_CONTEXT (member_scope);
1935 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1937 if (complain & tf_error)
1939 if (TREE_CODE (member) == FIELD_DECL)
1940 error ("invalid use of nonstatic data member %qE", member);
1942 error ("%qD is not a member of %qT", member, object_type);
1944 return error_mark_node;
1947 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1948 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1949 in the front end; only _DECLs and _REFs are lvalues in the back end. */
1951 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1953 object = cp_build_indirect_ref (temp, NULL, complain);
1956 /* In [expr.ref], there is an explicit list of the valid choices for
1957 MEMBER. We check for each of those cases here. */
1958 if (TREE_CODE (member) == VAR_DECL)
1960 /* A static data member. */
1962 /* If OBJECT has side-effects, they are supposed to occur. */
1963 if (TREE_SIDE_EFFECTS (object))
1964 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1966 else if (TREE_CODE (member) == FIELD_DECL)
1968 /* A non-static data member. */
1973 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1974 && integer_zerop (TREE_OPERAND (object, 0)));
1976 /* Convert OBJECT to the type of MEMBER. */
1977 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1978 TYPE_MAIN_VARIANT (member_scope)))
1983 binfo = lookup_base (access_path ? access_path : object_type,
1984 member_scope, ba_unique, &kind);
1985 if (binfo == error_mark_node)
1986 return error_mark_node;
1988 /* It is invalid to try to get to a virtual base of a
1989 NULL object. The most common cause is invalid use of
1991 if (null_object_p && kind == bk_via_virtual)
1993 if (complain & tf_error)
1995 error ("invalid access to non-static data member %qD of "
1998 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
2000 return error_mark_node;
2003 /* Convert to the base. */
2004 object = build_base_path (PLUS_EXPR, object, binfo,
2006 /* If we found the base successfully then we should be able
2007 to convert to it successfully. */
2008 gcc_assert (object != error_mark_node);
2011 /* Complain about other invalid uses of offsetof, even though they will
2012 give the right answer. Note that we complain whether or not they
2013 actually used the offsetof macro, since there's no way to know at this
2014 point. So we just give a warning, instead of a pedwarn. */
2015 /* Do not produce this warning for base class field references, because
2016 we know for a fact that didn't come from offsetof. This does occur
2017 in various testsuite cases where a null object is passed where a
2018 vtable access is required. */
2019 if (null_object_p && warn_invalid_offsetof
2020 && CLASSTYPE_NON_POD_P (object_type)
2021 && !DECL_FIELD_IS_BASE (member)
2023 && (complain & tf_warning))
2025 warning (OPT_Winvalid_offsetof,
2026 "invalid access to non-static data member %qD "
2027 " of NULL object", member);
2028 warning (OPT_Winvalid_offsetof,
2029 "(perhaps the %<offsetof%> macro was used incorrectly)");
2032 /* If MEMBER is from an anonymous aggregate, we have converted
2033 OBJECT so that it refers to the class containing the
2034 anonymous union. Generate a reference to the anonymous union
2035 itself, and recur to find MEMBER. */
2036 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2037 /* When this code is called from build_field_call, the
2038 object already has the type of the anonymous union.
2039 That is because the COMPONENT_REF was already
2040 constructed, and was then disassembled before calling
2041 build_field_call. After the function-call code is
2042 cleaned up, this waste can be eliminated. */
2043 && (!same_type_ignoring_top_level_qualifiers_p
2044 (TREE_TYPE (object), DECL_CONTEXT (member))))
2046 tree anonymous_union;
2048 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2049 DECL_CONTEXT (member));
2050 object = build_class_member_access_expr (object,
2052 /*access_path=*/NULL_TREE,
2057 /* Compute the type of the field, as described in [expr.ref]. */
2058 type_quals = TYPE_UNQUALIFIED;
2059 member_type = TREE_TYPE (member);
2060 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2062 type_quals = (cp_type_quals (member_type)
2063 | cp_type_quals (object_type));
2065 /* A field is const (volatile) if the enclosing object, or the
2066 field itself, is const (volatile). But, a mutable field is
2067 not const, even within a const object. */
2068 if (DECL_MUTABLE_P (member))
2069 type_quals &= ~TYPE_QUAL_CONST;
2070 member_type = cp_build_qualified_type (member_type, type_quals);
2073 result = build3 (COMPONENT_REF, member_type, object, member,
2075 result = fold_if_not_in_template (result);
2077 /* Mark the expression const or volatile, as appropriate. Even
2078 though we've dealt with the type above, we still have to mark the
2079 expression itself. */
2080 if (type_quals & TYPE_QUAL_CONST)
2081 TREE_READONLY (result) = 1;
2082 if (type_quals & TYPE_QUAL_VOLATILE)
2083 TREE_THIS_VOLATILE (result) = 1;
2085 else if (BASELINK_P (member))
2087 /* The member is a (possibly overloaded) member function. */
2091 /* If the MEMBER is exactly one static member function, then we
2092 know the type of the expression. Otherwise, we must wait
2093 until overload resolution has been performed. */
2094 functions = BASELINK_FUNCTIONS (member);
2095 if (TREE_CODE (functions) == FUNCTION_DECL
2096 && DECL_STATIC_FUNCTION_P (functions))
2097 type = TREE_TYPE (functions);
2099 type = unknown_type_node;
2100 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2101 base. That will happen when the function is called. */
2102 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2104 else if (TREE_CODE (member) == CONST_DECL)
2106 /* The member is an enumerator. */
2108 /* If OBJECT has side-effects, they are supposed to occur. */
2109 if (TREE_SIDE_EFFECTS (object))
2110 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2115 if (complain & tf_error)
2116 error ("invalid use of %qD", member);
2117 return error_mark_node;
2120 if (!preserve_reference)
2123 If E2 is declared to have type "reference to T", then ... the
2124 type of E1.E2 is T. */
2125 result = convert_from_reference (result);
2130 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2131 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2134 lookup_destructor (tree object, tree scope, tree dtor_name)
2136 tree object_type = TREE_TYPE (object);
2137 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2140 if (scope && !check_dtor_name (scope, dtor_type))
2142 error ("qualified type %qT does not match destructor name ~%qT",
2144 return error_mark_node;
2146 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2148 /* In a template, names we can't find a match for are still accepted
2149 destructor names, and we check them here. */
2150 if (check_dtor_name (object_type, dtor_type))
2151 dtor_type = object_type;
2154 error ("object type %qT does not match destructor name ~%qT",
2155 object_type, dtor_type);
2156 return error_mark_node;
2160 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2162 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2163 TYPE_MAIN_VARIANT (object_type), dtor_type);
2164 return error_mark_node;
2166 expr = lookup_member (dtor_type, complete_dtor_identifier,
2167 /*protect=*/1, /*want_type=*/false);
2168 expr = (adjust_result_of_qualified_name_lookup
2169 (expr, dtor_type, object_type));
2173 /* An expression of the form "A::template B" has been resolved to
2174 DECL. Issue a diagnostic if B is not a template or template
2178 check_template_keyword (tree decl)
2180 /* The standard says:
2184 If a name prefixed by the keyword template is not a member
2185 template, the program is ill-formed.
2187 DR 228 removed the restriction that the template be a member
2190 DR 96, if accepted would add the further restriction that explicit
2191 template arguments must be provided if the template keyword is
2192 used, but, as of 2005-10-16, that DR is still in "drafting". If
2193 this DR is accepted, then the semantic checks here can be
2194 simplified, as the entity named must in fact be a template
2195 specialization, rather than, as at present, a set of overloaded
2196 functions containing at least one template function. */
2197 if (TREE_CODE (decl) != TEMPLATE_DECL
2198 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2200 if (!is_overloaded_fn (decl))
2201 permerror (input_location, "%qD is not a template", decl);
2206 if (BASELINK_P (fns))
2207 fns = BASELINK_FUNCTIONS (fns);
2210 tree fn = OVL_CURRENT (fns);
2211 if (TREE_CODE (fn) == TEMPLATE_DECL
2212 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2214 if (TREE_CODE (fn) == FUNCTION_DECL
2215 && DECL_USE_TEMPLATE (fn)
2216 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2218 fns = OVL_NEXT (fns);
2221 permerror (input_location, "%qD is not a template", decl);
2226 /* This function is called by the parser to process a class member
2227 access expression of the form OBJECT.NAME. NAME is a node used by
2228 the parser to represent a name; it is not yet a DECL. It may,
2229 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2230 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2231 there is no reason to do the lookup twice, so the parser keeps the
2232 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2233 be a template via the use of the "A::template B" syntax. */
2236 finish_class_member_access_expr (tree object, tree name, bool template_p,
2237 tsubst_flags_t complain)
2242 tree access_path = NULL_TREE;
2243 tree orig_object = object;
2244 tree orig_name = name;
2246 if (object == error_mark_node || name == error_mark_node)
2247 return error_mark_node;
2249 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2250 if (!objc_is_public (object, name))
2251 return error_mark_node;
2253 object_type = TREE_TYPE (object);
2255 if (processing_template_decl)
2257 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2258 dependent_type_p (object_type)
2259 /* If NAME is just an IDENTIFIER_NODE, then the expression
2261 || TREE_CODE (object) == IDENTIFIER_NODE
2262 /* If NAME is "f<args>", where either 'f' or 'args' is
2263 dependent, then the expression is dependent. */
2264 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2265 && dependent_template_id_p (TREE_OPERAND (name, 0),
2266 TREE_OPERAND (name, 1)))
2267 /* If NAME is "T::X" where "T" is dependent, then the
2268 expression is dependent. */
2269 || (TREE_CODE (name) == SCOPE_REF
2270 && TYPE_P (TREE_OPERAND (name, 0))
2271 && dependent_type_p (TREE_OPERAND (name, 0))))
2272 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2273 object = build_non_dependent_expr (object);
2278 The type of the first expression shall be "class object" (of a
2280 if (!currently_open_class (object_type)
2281 && !complete_type_or_else (object_type, object))
2282 return error_mark_node;
2283 if (!CLASS_TYPE_P (object_type))
2285 if (complain & tf_error)
2286 error ("request for member %qD in %qE, which is of non-class type %qT",
2287 name, object, object_type);
2288 return error_mark_node;
2291 if (BASELINK_P (name))
2292 /* A member function that has already been looked up. */
2296 bool is_template_id = false;
2297 tree template_args = NULL_TREE;
2300 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2302 is_template_id = true;
2303 template_args = TREE_OPERAND (name, 1);
2304 name = TREE_OPERAND (name, 0);
2306 if (TREE_CODE (name) == OVERLOAD)
2307 name = DECL_NAME (get_first_fn (name));
2308 else if (DECL_P (name))
2309 name = DECL_NAME (name);
2312 if (TREE_CODE (name) == SCOPE_REF)
2314 /* A qualified name. The qualifying class or namespace `S'
2315 has already been looked up; it is either a TYPE or a
2317 scope = TREE_OPERAND (name, 0);
2318 name = TREE_OPERAND (name, 1);
2320 /* If SCOPE is a namespace, then the qualified name does not
2321 name a member of OBJECT_TYPE. */
2322 if (TREE_CODE (scope) == NAMESPACE_DECL)
2324 if (complain & tf_error)
2325 error ("%<%D::%D%> is not a member of %qT",
2326 scope, name, object_type);
2327 return error_mark_node;
2330 gcc_assert (CLASS_TYPE_P (scope));
2331 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2332 || TREE_CODE (name) == BIT_NOT_EXPR);
2334 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2335 access_path = lookup_base (object_type, scope, ba_check, NULL);
2336 if (access_path == error_mark_node)
2337 return error_mark_node;
2340 if (complain & tf_error)
2341 error ("%qT is not a base of %qT", scope, object_type);
2342 return error_mark_node;
2348 access_path = object_type;
2351 if (TREE_CODE (name) == BIT_NOT_EXPR)
2352 member = lookup_destructor (object, scope, name);
2355 /* Look up the member. */
2356 member = lookup_member (access_path, name, /*protect=*/1,
2357 /*want_type=*/false);
2358 if (member == NULL_TREE)
2360 if (complain & tf_error)
2361 error ("%qD has no member named %qE", object_type, name);
2362 return error_mark_node;
2364 if (member == error_mark_node)
2365 return error_mark_node;
2370 tree templ = member;
2372 if (BASELINK_P (templ))
2373 templ = lookup_template_function (templ, template_args);
2376 if (complain & tf_error)
2377 error ("%qD is not a member template function", name);
2378 return error_mark_node;
2383 if (TREE_DEPRECATED (member))
2384 warn_deprecated_use (member, NULL_TREE);
2387 check_template_keyword (member);
2389 expr = build_class_member_access_expr (object, member, access_path,
2390 /*preserve_reference=*/false,
2392 if (processing_template_decl && expr != error_mark_node)
2394 if (BASELINK_P (member))
2396 if (TREE_CODE (orig_name) == SCOPE_REF)
2397 BASELINK_QUALIFIED_P (member) = 1;
2400 return build_min_non_dep (COMPONENT_REF, expr,
2401 orig_object, orig_name,
2408 /* Return an expression for the MEMBER_NAME field in the internal
2409 representation of PTRMEM, a pointer-to-member function. (Each
2410 pointer-to-member function type gets its own RECORD_TYPE so it is
2411 more convenient to access the fields by name than by FIELD_DECL.)
2412 This routine converts the NAME to a FIELD_DECL and then creates the
2413 node for the complete expression. */
2416 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2422 /* This code is a stripped down version of
2423 build_class_member_access_expr. It does not work to use that
2424 routine directly because it expects the object to be of class
2426 ptrmem_type = TREE_TYPE (ptrmem);
2427 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2428 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2429 /*want_type=*/false);
2430 member_type = cp_build_qualified_type (TREE_TYPE (member),
2431 cp_type_quals (ptrmem_type));
2432 return fold_build3 (COMPONENT_REF, member_type,
2433 ptrmem, member, NULL_TREE);
2436 /* Given an expression PTR for a pointer, return an expression
2437 for the value pointed to.
2438 ERRORSTRING is the name of the operator to appear in error messages.
2440 This function may need to overload OPERATOR_FNNAME.
2441 Must also handle REFERENCE_TYPEs for C++. */
2444 build_x_indirect_ref (tree expr, const char *errorstring,
2445 tsubst_flags_t complain)
2447 tree orig_expr = expr;
2450 if (processing_template_decl)
2452 if (type_dependent_expression_p (expr))
2453 return build_min_nt (INDIRECT_REF, expr);
2454 expr = build_non_dependent_expr (expr);
2457 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2458 NULL_TREE, /*overloaded_p=*/NULL, complain);
2460 rval = cp_build_indirect_ref (expr, errorstring, complain);
2462 if (processing_template_decl && rval != error_mark_node)
2463 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2468 /* Helper function called from c-common. */
2470 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2471 tree ptr, const char *errorstring)
2473 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2477 cp_build_indirect_ref (tree ptr, const char *errorstring,
2478 tsubst_flags_t complain)
2482 if (ptr == error_mark_node)
2483 return error_mark_node;
2485 if (ptr == current_class_ptr)
2486 return current_class_ref;
2488 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2489 ? ptr : decay_conversion (ptr));
2490 type = TREE_TYPE (pointer);
2492 if (POINTER_TYPE_P (type))
2496 If the type of the expression is "pointer to T," the type
2497 of the result is "T."
2499 We must use the canonical variant because certain parts of
2500 the back end, like fold, do pointer comparisons between
2502 tree t = canonical_type_variant (TREE_TYPE (type));
2504 if (CONVERT_EXPR_P (ptr)
2505 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2507 /* If a warning is issued, mark it to avoid duplicates from
2508 the backend. This only needs to be done at
2509 warn_strict_aliasing > 2. */
2510 if (warn_strict_aliasing > 2)
2511 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2512 type, TREE_OPERAND (ptr, 0)))
2513 TREE_NO_WARNING (ptr) = 1;
2516 if (VOID_TYPE_P (t))
2518 /* A pointer to incomplete type (other than cv void) can be
2519 dereferenced [expr.unary.op]/1 */
2520 if (complain & tf_error)
2521 error ("%qT is not a pointer-to-object type", type);
2522 return error_mark_node;
2524 else if (TREE_CODE (pointer) == ADDR_EXPR
2525 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2526 /* The POINTER was something like `&x'. We simplify `*&x' to
2528 return TREE_OPERAND (pointer, 0);
2531 tree ref = build1 (INDIRECT_REF, t, pointer);
2533 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2534 so that we get the proper error message if the result is used
2535 to assign to. Also, &* is supposed to be a no-op. */
2536 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2537 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2538 TREE_SIDE_EFFECTS (ref)
2539 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2543 else if (!(complain & tf_error))
2544 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2546 /* `pointer' won't be an error_mark_node if we were given a
2547 pointer to member, so it's cool to check for this here. */
2548 else if (TYPE_PTR_TO_MEMBER_P (type))
2549 error ("invalid use of %qs on pointer to member", errorstring);
2550 else if (pointer != error_mark_node)
2553 error ("invalid type argument of %qs", errorstring);
2555 error ("invalid type argument");
2557 return error_mark_node;
2560 /* This handles expressions of the form "a[i]", which denotes
2563 This is logically equivalent in C to *(a+i), but we may do it differently.
2564 If A is a variable or a member, we generate a primitive ARRAY_REF.
2565 This avoids forcing the array out of registers, and can work on
2566 arrays that are not lvalues (for example, members of structures returned
2569 If INDEX is of some user-defined type, it must be converted to
2570 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2571 will inherit the type of the array, which will be some pointer type.
2573 LOC is the location to use in building the array reference. */
2576 build_array_ref (tree array, tree idx, location_t loc)
2582 error_at (loc, "subscript missing in array reference");
2583 return error_mark_node;
2586 if (TREE_TYPE (array) == error_mark_node
2587 || TREE_TYPE (idx) == error_mark_node)
2588 return error_mark_node;
2590 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2592 switch (TREE_CODE (array))
2596 tree value = build_array_ref (TREE_OPERAND (array, 1), idx, loc);
2597 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2598 TREE_OPERAND (array, 0), value);
2599 SET_EXPR_LOCATION (ret, loc);
2604 ret = build_conditional_expr
2605 (TREE_OPERAND (array, 0),
2606 build_array_ref (TREE_OPERAND (array, 1), idx, loc),
2607 build_array_ref (TREE_OPERAND (array, 2), idx, loc),
2608 tf_warning_or_error);
2609 protected_set_expr_location (ret, loc);
2616 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2620 warn_array_subscript_with_type_char (idx);
2622 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2624 error_at (loc, "array subscript is not an integer");
2625 return error_mark_node;
2628 /* Apply integral promotions *after* noticing character types.
2629 (It is unclear why we do these promotions -- the standard
2630 does not say that we should. In fact, the natural thing would
2631 seem to be to convert IDX to ptrdiff_t; we're performing
2632 pointer arithmetic.) */
2633 idx = perform_integral_promotions (idx);
2635 /* An array that is indexed by a non-constant
2636 cannot be stored in a register; we must be able to do
2637 address arithmetic on its address.
2638 Likewise an array of elements of variable size. */
2639 if (TREE_CODE (idx) != INTEGER_CST
2640 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2641 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2644 if (!cxx_mark_addressable (array))
2645 return error_mark_node;
2648 /* An array that is indexed by a constant value which is not within
2649 the array bounds cannot be stored in a register either; because we
2650 would get a crash in store_bit_field/extract_bit_field when trying
2651 to access a non-existent part of the register. */
2652 if (TREE_CODE (idx) == INTEGER_CST
2653 && TYPE_DOMAIN (TREE_TYPE (array))
2654 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2656 if (!cxx_mark_addressable (array))
2657 return error_mark_node;
2660 if (!lvalue_p (array))
2661 pedwarn (loc, OPT_pedantic,
2662 "ISO C++ forbids subscripting non-lvalue array");
2664 /* Note in C++ it is valid to subscript a `register' array, since
2665 it is valid to take the address of something with that
2666 storage specification. */
2670 while (TREE_CODE (foo) == COMPONENT_REF)
2671 foo = TREE_OPERAND (foo, 0);
2672 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2673 warning_at (loc, OPT_Wextra,
2674 "subscripting array declared %<register%>");
2677 type = TREE_TYPE (TREE_TYPE (array));
2678 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2679 /* Array ref is const/volatile if the array elements are
2680 or if the array is.. */
2681 TREE_READONLY (rval)
2682 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2683 TREE_SIDE_EFFECTS (rval)
2684 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2685 TREE_THIS_VOLATILE (rval)
2686 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2687 ret = require_complete_type (fold_if_not_in_template (rval));
2688 protected_set_expr_location (ret, loc);
2693 tree ar = default_conversion (array);
2694 tree ind = default_conversion (idx);
2696 /* Put the integer in IND to simplify error checking. */
2697 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2704 if (ar == error_mark_node)
2707 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2709 error_at (loc, "subscripted value is neither array nor pointer");
2710 return error_mark_node;
2712 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2714 error_at (loc, "array subscript is not an integer");
2715 return error_mark_node;
2718 warn_array_subscript_with_type_char (idx);
2720 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2722 tf_warning_or_error),
2724 tf_warning_or_error);
2725 protected_set_expr_location (ret, loc);
2730 /* Resolve a pointer to member function. INSTANCE is the object
2731 instance to use, if the member points to a virtual member.
2733 This used to avoid checking for virtual functions if basetype
2734 has no virtual functions, according to an earlier ANSI draft.
2735 With the final ISO C++ rules, such an optimization is
2736 incorrect: A pointer to a derived member can be static_cast
2737 to pointer-to-base-member, as long as the dynamic object
2738 later has the right member. */
2741 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2743 if (TREE_CODE (function) == OFFSET_REF)
2744 function = TREE_OPERAND (function, 1);
2746 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2748 tree idx, delta, e1, e2, e3, vtbl, basetype;
2749 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2751 tree instance_ptr = *instance_ptrptr;
2752 tree instance_save_expr = 0;
2753 if (instance_ptr == error_mark_node)
2755 if (TREE_CODE (function) == PTRMEM_CST)
2757 /* Extracting the function address from a pmf is only
2758 allowed with -Wno-pmf-conversions. It only works for
2760 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2761 e1 = convert (fntype, e1);
2766 error ("object missing in use of %qE", function);
2767 return error_mark_node;
2771 if (TREE_SIDE_EFFECTS (instance_ptr))
2772 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2774 if (TREE_SIDE_EFFECTS (function))
2775 function = save_expr (function);
2777 /* Start by extracting all the information from the PMF itself. */
2778 e3 = pfn_from_ptrmemfunc (function);
2779 delta = delta_from_ptrmemfunc (function);
2780 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2781 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2783 case ptrmemfunc_vbit_in_pfn:
2784 e1 = cp_build_binary_op (input_location,
2785 BIT_AND_EXPR, idx, integer_one_node,
2786 tf_warning_or_error);
2787 idx = cp_build_binary_op (input_location,
2788 MINUS_EXPR, idx, integer_one_node,
2789 tf_warning_or_error);
2792 case ptrmemfunc_vbit_in_delta:
2793 e1 = cp_build_binary_op (input_location,
2794 BIT_AND_EXPR, delta, integer_one_node,
2795 tf_warning_or_error);
2796 delta = cp_build_binary_op (input_location,
2797 RSHIFT_EXPR, delta, integer_one_node,
2798 tf_warning_or_error);
2805 /* Convert down to the right base before using the instance. A
2806 special case is that in a pointer to member of class C, C may
2807 be incomplete. In that case, the function will of course be
2808 a member of C, and no conversion is required. In fact,
2809 lookup_base will fail in that case, because incomplete
2810 classes do not have BINFOs. */
2811 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2812 if (!same_type_ignoring_top_level_qualifiers_p
2813 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2815 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2816 basetype, ba_check, NULL);
2817 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2819 if (instance_ptr == error_mark_node)
2820 return error_mark_node;
2822 /* ...and then the delta in the PMF. */
2823 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2824 instance_ptr, fold_convert (sizetype, delta));
2826 /* Hand back the adjusted 'this' argument to our caller. */
2827 *instance_ptrptr = instance_ptr;
2829 /* Next extract the vtable pointer from the object. */
2830 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2832 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2833 /* If the object is not dynamic the access invokes undefined
2834 behavior. As it is not executed in this case silence the
2835 spurious warnings it may provoke. */
2836 TREE_NO_WARNING (vtbl) = 1;
2838 /* Finally, extract the function pointer from the vtable. */
2839 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2840 fold_convert (sizetype, idx));
2841 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2842 TREE_CONSTANT (e2) = 1;
2844 /* When using function descriptors, the address of the
2845 vtable entry is treated as a function pointer. */
2846 if (TARGET_VTABLE_USES_DESCRIPTORS)
2847 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2848 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2849 tf_warning_or_error));
2851 e2 = fold_convert (TREE_TYPE (e3), e2);
2852 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2854 /* Make sure this doesn't get evaluated first inside one of the
2855 branches of the COND_EXPR. */
2856 if (instance_save_expr)
2857 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2858 instance_save_expr, e1);
2865 /* Used by the C-common bits. */
2867 build_function_call (tree function, tree params)
2869 return cp_build_function_call (function, params, tf_warning_or_error);
2872 /* Used by the C-common bits. */
2874 build_function_call_vec (tree function, VEC(tree,gc) *params,
2875 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
2877 VEC(tree,gc) *orig_params = params;
2878 tree ret = cp_build_function_call_vec (function, ¶ms,
2879 tf_warning_or_error);
2881 /* cp_build_function_call_vec can reallocate PARAMS by adding
2882 default arguments. That should never happen here. Verify
2884 gcc_assert (params == orig_params);
2889 /* Build a function call using a tree list of arguments. */
2892 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2897 vec = make_tree_vector ();
2898 for (; params != NULL_TREE; params = TREE_CHAIN (params))
2899 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
2900 ret = cp_build_function_call_vec (function, &vec, complain);
2901 release_tree_vector (vec);
2905 /* Build a function call using a vector of arguments. PARAMS may be
2906 NULL if there are no parameters. This changes the contents of
2910 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
2911 tsubst_flags_t complain)
2913 tree fntype, fndecl;
2914 tree name = NULL_TREE;
2916 tree original = function;
2920 VEC(tree,gc) *allocated = NULL;
2923 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2924 expressions, like those used for ObjC messenger dispatches. */
2925 if (params != NULL && !VEC_empty (tree, *params))
2926 function = objc_rewrite_function_call (function,
2927 VEC_index (tree, *params, 0));
2929 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2930 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2931 if (TREE_CODE (function) == NOP_EXPR
2932 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2933 function = TREE_OPERAND (function, 0);
2935 if (TREE_CODE (function) == FUNCTION_DECL)
2937 name = DECL_NAME (function);
2939 mark_used (function);
2942 /* Convert anything with function type to a pointer-to-function. */
2943 if (DECL_MAIN_P (function) && (complain & tf_error))
2944 pedwarn (input_location, OPT_pedantic,
2945 "ISO C++ forbids calling %<::main%> from within program");
2947 function = build_addr_func (function);
2953 function = build_addr_func (function);
2956 if (function == error_mark_node)
2957 return error_mark_node;
2959 fntype = TREE_TYPE (function);
2961 if (TYPE_PTRMEMFUNC_P (fntype))
2963 if (complain & tf_error)
2964 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2965 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2966 original, original);
2967 return error_mark_node;
2970 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2971 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2973 if (!((TREE_CODE (fntype) == POINTER_TYPE
2974 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2976 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2978 if (complain & tf_error)
2979 error ("%qE cannot be used as a function", original);
2980 return error_mark_node;
2983 /* fntype now gets the type of function pointed to. */
2984 fntype = TREE_TYPE (fntype);
2985 parm_types = TYPE_ARG_TYPES (fntype);
2989 allocated = make_tree_vector ();
2990 params = &allocated;
2993 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
2996 return error_mark_node;
2998 argarray = VEC_address (tree, *params);
3000 /* Check for errors in format strings and inappropriately
3002 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
3005 ret = build_cxx_call (function, nargs, argarray);
3007 if (allocated != NULL)
3008 release_tree_vector (allocated);
3013 /* Convert the actual parameter expressions in the list VALUES to the
3014 types in the list TYPELIST. The converted expressions are stored
3015 back in the VALUES vector.
3016 If parmdecls is exhausted, or when an element has NULL as its type,
3017 perform the default conversions.
3019 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3021 This is also where warnings about wrong number of args are generated.
3023 Returns the actual number of arguments processed (which might be less
3024 than the length of the vector), or -1 on error.
3026 In C++, unspecified trailing parameters can be filled in with their
3027 default arguments, if such were specified. Do so here. */
3030 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3031 int flags, tsubst_flags_t complain)
3034 const char *called_thing = 0;
3037 /* Argument passing is always copy-initialization. */
3038 flags |= LOOKUP_ONLYCONVERTING;
3042 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3044 if (DECL_NAME (fndecl) == NULL_TREE
3045 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3046 called_thing = "constructor";
3048 called_thing = "member function";
3051 called_thing = "function";
3054 for (i = 0, typetail = typelist;
3055 i < VEC_length (tree, *values);
3058 tree type = typetail ? TREE_VALUE (typetail) : 0;
3059 tree val = VEC_index (tree, *values, i);
3061 if (val == error_mark_node || type == error_mark_node)
3064 if (type == void_type_node)
3066 if (complain & tf_error)
3070 error ("too many arguments to %s %q+#D",
3071 called_thing, fndecl);
3072 error ("at this point in file");
3075 error ("too many arguments to function");
3082 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3083 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3084 if (TREE_CODE (val) == NOP_EXPR
3085 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3086 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3087 val = TREE_OPERAND (val, 0);
3089 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3091 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3092 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3093 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3094 val = decay_conversion (val);
3097 if (val == error_mark_node)
3102 /* Formal parm type is specified by a function prototype. */
3105 if (!COMPLETE_TYPE_P (complete_type (type)))
3107 if (complain & tf_error)
3110 error ("parameter %P of %qD has incomplete type %qT",
3113 error ("parameter %P has incomplete type %qT", i, type);
3115 parmval = error_mark_node;
3119 parmval = convert_for_initialization
3120 (NULL_TREE, type, val, flags,
3121 "argument passing", fndecl, i, complain);
3122 parmval = convert_for_arg_passing (type, parmval);
3125 if (parmval == error_mark_node)
3128 VEC_replace (tree, *values, i, parmval);
3132 if (fndecl && DECL_BUILT_IN (fndecl)
3133 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3134 /* Don't do ellipsis conversion for __built_in_constant_p
3135 as this will result in spurious warnings for non-POD
3137 val = require_complete_type (val);
3139 val = convert_arg_to_ellipsis (val);
3141 VEC_replace (tree, *values, i, val);
3145 typetail = TREE_CHAIN (typetail);
3148 if (typetail != 0 && typetail != void_list_node)
3150 /* See if there are default arguments that can be used. Because
3151 we hold default arguments in the FUNCTION_TYPE (which is so
3152 wrong), we can see default parameters here from deduced
3153 contexts (and via typeof) for indirect function calls.
3154 Fortunately we know whether we have a function decl to
3155 provide default arguments in a language conformant
3157 if (fndecl && TREE_PURPOSE (typetail)
3158 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3160 for (; typetail != void_list_node; ++i)
3163 = convert_default_arg (TREE_VALUE (typetail),
3164 TREE_PURPOSE (typetail),
3167 if (parmval == error_mark_node)
3170 VEC_safe_push (tree, gc, *values, parmval);
3171 typetail = TREE_CHAIN (typetail);
3172 /* ends with `...'. */
3173 if (typetail == NULL_TREE)
3179 if (complain & tf_error)
3183 error ("too few arguments to %s %q+#D",
3184 called_thing, fndecl);
3185 error ("at this point in file");
3188 error ("too few arguments to function");
3197 /* Build a binary-operation expression, after performing default
3198 conversions on the operands. CODE is the kind of expression to
3199 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3200 are the tree codes which correspond to ARG1 and ARG2 when issuing
3201 warnings about possibly misplaced parentheses. They may differ
3202 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3203 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3204 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3205 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3206 ARG2_CODE as ERROR_MARK. */
3209 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3210 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3211 tsubst_flags_t complain)
3220 if (processing_template_decl)
3222 if (type_dependent_expression_p (arg1)
3223 || type_dependent_expression_p (arg2))
3224 return build_min_nt (code, arg1, arg2);
3225 arg1 = build_non_dependent_expr (arg1);
3226 arg2 = build_non_dependent_expr (arg2);
3229 if (code == DOTSTAR_EXPR)
3230 expr = build_m_component_ref (arg1, arg2);
3232 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3233 overloaded_p, complain);
3235 /* Check for cases such as x+y<<z which users are likely to
3236 misinterpret. But don't warn about obj << x + y, since that is a
3237 common idiom for I/O. */
3238 if (warn_parentheses
3239 && !processing_template_decl
3240 && !error_operand_p (arg1)
3241 && !error_operand_p (arg2)
3242 && (code != LSHIFT_EXPR
3243 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3244 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3246 if (processing_template_decl && expr != error_mark_node)
3247 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3252 /* Build and return an ARRAY_REF expression. */
3255 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3257 tree orig_arg1 = arg1;
3258 tree orig_arg2 = arg2;
3261 if (processing_template_decl)
3263 if (type_dependent_expression_p (arg1)
3264 || type_dependent_expression_p (arg2))
3265 return build_min_nt (ARRAY_REF, arg1, arg2,
3266 NULL_TREE, NULL_TREE);
3267 arg1 = build_non_dependent_expr (arg1);
3268 arg2 = build_non_dependent_expr (arg2);
3271 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3272 /*overloaded_p=*/NULL, complain);
3274 if (processing_template_decl && expr != error_mark_node)
3275 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3276 NULL_TREE, NULL_TREE);
3280 /* For the c-common bits. */
3282 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3283 int convert_p ATTRIBUTE_UNUSED)
3285 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3289 /* Build a binary-operation expression without default conversions.
3290 CODE is the kind of expression to build.
3291 LOCATION is the location_t of the operator in the source code.
3292 This function differs from `build' in several ways:
3293 the data type of the result is computed and recorded in it,
3294 warnings are generated if arg data types are invalid,
3295 special handling for addition and subtraction of pointers is known,
3296 and some optimization is done (operations on narrow ints
3297 are done in the narrower type when that gives the same result).
3298 Constant folding is also done before the result is returned.
3300 Note that the operands will never have enumeral types
3301 because either they have just had the default conversions performed
3302 or they have both just been converted to some other type in which
3303 the arithmetic is to be done.
3305 C++: must do special pointer arithmetic when implementing
3306 multiple inheritance, and deal with pointer to member functions. */
3309 cp_build_binary_op (location_t location,
3310 enum tree_code code, tree orig_op0, tree orig_op1,
3311 tsubst_flags_t complain)
3314 enum tree_code code0, code1;
3316 const char *invalid_op_diag;
3318 /* Expression code to give to the expression when it is built.
3319 Normally this is CODE, which is what the caller asked for,
3320 but in some special cases we change it. */
3321 enum tree_code resultcode = code;
3323 /* Data type in which the computation is to be performed.
3324 In the simplest cases this is the common type of the arguments. */
3325 tree result_type = NULL;
3327 /* Nonzero means operands have already been type-converted
3328 in whatever way is necessary.
3329 Zero means they need to be converted to RESULT_TYPE. */
3332 /* Nonzero means create the expression with this type, rather than
3334 tree build_type = 0;
3336 /* Nonzero means after finally constructing the expression
3337 convert it to this type. */
3338 tree final_type = 0;
3342 /* Nonzero if this is an operation like MIN or MAX which can
3343 safely be computed in short if both args are promoted shorts.
3344 Also implies COMMON.
3345 -1 indicates a bitwise operation; this makes a difference
3346 in the exact conditions for when it is safe to do the operation
3347 in a narrower mode. */
3350 /* Nonzero if this is a comparison operation;
3351 if both args are promoted shorts, compare the original shorts.
3352 Also implies COMMON. */
3353 int short_compare = 0;
3355 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3358 /* True if both operands have arithmetic type. */
3359 bool arithmetic_types_p;
3361 /* Apply default conversions. */
3365 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3366 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3367 || code == TRUTH_XOR_EXPR)
3369 if (!really_overloaded_fn (op0))
3370 op0 = decay_conversion (op0);
3371 if (!really_overloaded_fn (op1))
3372 op1 = decay_conversion (op1);
3376 if (!really_overloaded_fn (op0))
3377 op0 = default_conversion (op0);
3378 if (!really_overloaded_fn (op1))
3379 op1 = default_conversion (op1);
3382 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3383 STRIP_TYPE_NOPS (op0);
3384 STRIP_TYPE_NOPS (op1);
3386 /* DTRT if one side is an overloaded function, but complain about it. */
3387 if (type_unknown_p (op0))
3389 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3390 if (t != error_mark_node)
3392 if (complain & tf_error)
3393 permerror (input_location, "assuming cast to type %qT from overloaded function",
3398 if (type_unknown_p (op1))
3400 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3401 if (t != error_mark_node)
3403 if (complain & tf_error)
3404 permerror (input_location, "assuming cast to type %qT from overloaded function",
3410 type0 = TREE_TYPE (op0);
3411 type1 = TREE_TYPE (op1);
3413 /* The expression codes of the data types of the arguments tell us
3414 whether the arguments are integers, floating, pointers, etc. */
3415 code0 = TREE_CODE (type0);
3416 code1 = TREE_CODE (type1);
3418 /* If an error was already reported for one of the arguments,
3419 avoid reporting another error. */
3421 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3422 return error_mark_node;
3424 if ((invalid_op_diag
3425 = targetm.invalid_binary_op (code, type0, type1)))
3427 error (invalid_op_diag);
3428 return error_mark_node;
3434 /* Subtraction of two similar pointers.
3435 We must subtract them as integers, then divide by object size. */
3436 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3437 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3439 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3440 /* In all other cases except pointer - int, the usual arithmetic
3442 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3447 /* The pointer - int case is just like pointer + int; fall
3450 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3451 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3455 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3456 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3457 if (processing_template_decl)
3459 result_type = TREE_TYPE (ptr_operand);
3462 return cp_pointer_int_sum (code,
3473 case TRUNC_DIV_EXPR:
3475 case FLOOR_DIV_EXPR:
3476 case ROUND_DIV_EXPR:
3477 case EXACT_DIV_EXPR:
3478 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3479 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3480 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3481 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3483 enum tree_code tcode0 = code0, tcode1 = code1;
3485 warn_for_div_by_zero (location, op1);
3487 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3488 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3489 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3490 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3492 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3493 resultcode = RDIV_EXPR;
3495 /* When dividing two signed integers, we have to promote to int.
3496 unless we divide by a constant != -1. Note that default
3497 conversion will have been performed on the operands at this
3498 point, so we have to dig out the original type to find out if
3500 shorten = ((TREE_CODE (op0) == NOP_EXPR
3501 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3502 || (TREE_CODE (op1) == INTEGER_CST
3503 && ! integer_all_onesp (op1)));
3512 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3513 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3514 && !VECTOR_FLOAT_TYPE_P (type0)
3515 && !VECTOR_FLOAT_TYPE_P (type1)))
3519 case TRUNC_MOD_EXPR:
3520 case FLOOR_MOD_EXPR:
3521 warn_for_div_by_zero (location, op1);
3523 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3524 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3525 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3527 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3529 /* Although it would be tempting to shorten always here, that loses
3530 on some targets, since the modulo instruction is undefined if the
3531 quotient can't be represented in the computation mode. We shorten
3532 only if unsigned or if dividing by something we know != -1. */
3533 shorten = ((TREE_CODE (op0) == NOP_EXPR
3534 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3535 || (TREE_CODE (op1) == INTEGER_CST
3536 && ! integer_all_onesp (op1)));
3541 case TRUTH_ANDIF_EXPR:
3542 case TRUTH_ORIF_EXPR:
3543 case TRUTH_AND_EXPR:
3545 result_type = boolean_type_node;
3548 /* Shift operations: result has same type as first operand;
3549 always convert second operand to int.
3550 Also set SHORT_SHIFT if shifting rightward. */
3553 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3555 result_type = type0;
3556 if (TREE_CODE (op1) == INTEGER_CST)
3558 if (tree_int_cst_lt (op1, integer_zero_node))
3560 if (complain & tf_warning)
3561 warning (0, "right shift count is negative");
3565 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3566 && (complain & tf_warning))
3567 warning (0, "right shift count >= width of type");
3570 /* Convert the shift-count to an integer, regardless of
3571 size of value being shifted. */
3572 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3573 op1 = cp_convert (integer_type_node, op1);
3574 /* Avoid converting op1 to result_type later. */
3580 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3582 result_type = type0;
3583 if (TREE_CODE (op1) == INTEGER_CST)
3585 if (tree_int_cst_lt (op1, integer_zero_node))
3587 if (complain & tf_warning)
3588 warning (0, "left shift count is negative");
3590 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3592 if (complain & tf_warning)
3593 warning (0, "left shift count >= width of type");
3596 /* Convert the shift-count to an integer, regardless of
3597 size of value being shifted. */
3598 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3599 op1 = cp_convert (integer_type_node, op1);
3600 /* Avoid converting op1 to result_type later. */
3607 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3609 result_type = type0;
3610 if (TREE_CODE (op1) == INTEGER_CST)
3612 if (tree_int_cst_lt (op1, integer_zero_node))
3614 if (complain & tf_warning)
3615 warning (0, (code == LROTATE_EXPR)
3616 ? G_("left rotate count is negative")
3617 : G_("right rotate count is negative"));
3619 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3621 if (complain & tf_warning)
3622 warning (0, (code == LROTATE_EXPR)
3623 ? G_("left rotate count >= width of type")
3624 : G_("right rotate count >= width of type"));
3627 /* Convert the shift-count to an integer, regardless of
3628 size of value being shifted. */
3629 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3630 op1 = cp_convert (integer_type_node, op1);
3636 if ((complain & tf_warning)
3637 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3638 warning (OPT_Wfloat_equal,
3639 "comparing floating point with == or != is unsafe");
3640 if ((complain & tf_warning)
3641 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3642 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3643 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3645 build_type = boolean_type_node;
3646 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3647 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
3648 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3649 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
3651 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3652 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3653 result_type = composite_pointer_type (type0, type1, op0, op1,
3654 "comparison", complain);
3655 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3656 && null_ptr_cst_p (op1))
3658 if (TREE_CODE (op0) == ADDR_EXPR
3659 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3661 if (complain & tf_warning)
3662 warning (OPT_Waddress, "the address of %qD will never be NULL",
3663 TREE_OPERAND (op0, 0));
3665 result_type = type0;
3667 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3668 && null_ptr_cst_p (op0))
3670 if (TREE_CODE (op1) == ADDR_EXPR
3671 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3673 if (complain & tf_warning)
3674 warning (OPT_Waddress, "the address of %qD will never be NULL",
3675 TREE_OPERAND (op1, 0));
3677 result_type = type1;
3679 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3681 result_type = type0;
3682 if (complain & tf_error)
3683 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3685 return error_mark_node;
3687 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3689 result_type = type1;
3690 if (complain & tf_error)
3691 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3693 return error_mark_node;
3695 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3697 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3698 == ptrmemfunc_vbit_in_delta)
3700 tree pfn0 = pfn_from_ptrmemfunc (op0);
3701 tree delta0 = delta_from_ptrmemfunc (op0);
3702 tree e1 = cp_build_binary_op (location,
3705 fold_convert (TREE_TYPE (pfn0),
3708 tree e2 = cp_build_binary_op (location,
3713 e2 = cp_build_binary_op (location,
3714 EQ_EXPR, e2, integer_zero_node,
3716 op0 = cp_build_binary_op (location,
3717 TRUTH_ANDIF_EXPR, e1, e2,
3719 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3723 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3724 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3726 result_type = TREE_TYPE (op0);
3728 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3729 return cp_build_binary_op (location, code, op1, op0, complain);
3730 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3733 /* E will be the final comparison. */
3735 /* E1 and E2 are for scratch. */
3743 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3746 if (!same_type_p (TREE_TYPE (op0), type))
3747 op0 = cp_convert_and_check (type, op0);
3748 if (!same_type_p (TREE_TYPE (op1), type))
3749 op1 = cp_convert_and_check (type, op1);
3751 if (op0 == error_mark_node || op1 == error_mark_node)
3752 return error_mark_node;
3754 if (TREE_SIDE_EFFECTS (op0))
3755 op0 = save_expr (op0);
3756 if (TREE_SIDE_EFFECTS (op1))
3757 op1 = save_expr (op1);
3759 pfn0 = pfn_from_ptrmemfunc (op0);
3760 pfn1 = pfn_from_ptrmemfunc (op1);
3761 delta0 = delta_from_ptrmemfunc (op0);
3762 delta1 = delta_from_ptrmemfunc (op1);
3763 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3764 == ptrmemfunc_vbit_in_delta)
3769 && ((op0.delta == op1.delta)
3770 || (!op0.pfn && op0.delta & 1 == 0
3771 && op1.delta & 1 == 0))
3773 The reason for the `!op0.pfn' bit is that a NULL
3774 pointer-to-member is any member with a zero PFN and
3775 LSB of the DELTA field is 0. */
3777 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3781 e1 = cp_build_binary_op (location,
3782 EQ_EXPR, e1, integer_zero_node,
3784 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3788 e2 = cp_build_binary_op (location,
3789 EQ_EXPR, e2, integer_zero_node,
3791 e1 = cp_build_binary_op (location,
3792 TRUTH_ANDIF_EXPR, e2, e1,
3794 e2 = cp_build_binary_op (location, EQ_EXPR,
3796 fold_convert (TREE_TYPE (pfn0),
3799 e2 = cp_build_binary_op (location,
3800 TRUTH_ANDIF_EXPR, e2, e1, complain);
3801 e1 = cp_build_binary_op (location,
3802 EQ_EXPR, delta0, delta1, complain);
3803 e1 = cp_build_binary_op (location,
3804 TRUTH_ORIF_EXPR, e1, e2, complain);
3811 && (!op0.pfn || op0.delta == op1.delta))
3813 The reason for the `!op0.pfn' bit is that a NULL
3814 pointer-to-member is any member with a zero PFN; the
3815 DELTA field is unspecified. */
3817 e1 = cp_build_binary_op (location,
3818 EQ_EXPR, delta0, delta1, complain);
3819 e2 = cp_build_binary_op (location,
3822 fold_convert (TREE_TYPE (pfn0),
3825 e1 = cp_build_binary_op (location,
3826 TRUTH_ORIF_EXPR, e1, e2, complain);
3828 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3829 e = cp_build_binary_op (location,
3830 TRUTH_ANDIF_EXPR, e2, e1, complain);
3831 if (code == EQ_EXPR)
3833 return cp_build_binary_op (location,
3834 EQ_EXPR, e, integer_zero_node, complain);
3838 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3839 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3841 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3842 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3850 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3851 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3853 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3854 result_type = composite_pointer_type (type0, type1, op0, op1,
3855 "comparison", complain);
3862 if (TREE_CODE (orig_op0) == STRING_CST
3863 || TREE_CODE (orig_op1) == STRING_CST)
3865 if (complain & tf_warning)
3866 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3869 build_type = boolean_type_node;
3870 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3871 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3873 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3874 result_type = composite_pointer_type (type0, type1, op0, op1,
3875 "comparison", complain);
3876 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3877 && integer_zerop (op1))
3878 result_type = type0;
3879 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3880 && integer_zerop (op0))
3881 result_type = type1;
3882 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3884 result_type = type0;
3885 if (complain & tf_error)
3886 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3888 return error_mark_node;
3890 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3892 result_type = type1;
3893 if (complain & tf_error)
3894 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3896 return error_mark_node;
3900 case UNORDERED_EXPR:
3907 build_type = integer_type_node;
3908 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3910 if (complain & tf_error)
3911 error ("unordered comparison on non-floating point argument");
3912 return error_mark_node;
3921 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
3922 || code0 == ENUMERAL_TYPE)
3923 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3924 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
3925 arithmetic_types_p = 1;
3928 arithmetic_types_p = 0;
3929 /* Vector arithmetic is only allowed when both sides are vectors. */
3930 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3932 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3933 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3936 binary_op_error (location, code, type0, type1);
3937 return error_mark_node;
3939 arithmetic_types_p = 1;
3942 /* Determine the RESULT_TYPE, if it is not already known. */
3944 && arithmetic_types_p
3945 && (shorten || common || short_compare))
3946 result_type = cp_common_type (type0, type1);
3950 if (complain & tf_error)
3951 error ("invalid operands of types %qT and %qT to binary %qO",
3952 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3953 return error_mark_node;
3956 /* If we're in a template, the only thing we need to know is the
3958 if (processing_template_decl)
3960 /* Since the middle-end checks the type when doing a build2, we
3961 need to build the tree in pieces. This built tree will never
3962 get out of the front-end as we replace it when instantiating
3964 tree tmp = build2 (resultcode,
3965 build_type ? build_type : result_type,
3967 TREE_OPERAND (tmp, 0) = op0;
3971 if (arithmetic_types_p)
3973 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3975 /* For certain operations (which identify themselves by shorten != 0)
3976 if both args were extended from the same smaller type,
3977 do the arithmetic in that type and then extend.
3979 shorten !=0 and !=1 indicates a bitwise operation.
3980 For them, this optimization is safe only if
3981 both args are zero-extended or both are sign-extended.
3982 Otherwise, we might change the result.
3983 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3984 but calculated in (unsigned short) it would be (unsigned short)-1. */
3986 if (shorten && none_complex)
3988 final_type = result_type;
3989 result_type = shorten_binary_op (result_type, op0, op1,
3993 /* Comparison operations are shortened too but differently.
3994 They identify themselves by setting short_compare = 1. */
3998 /* Don't write &op0, etc., because that would prevent op0
3999 from being kept in a register.
4000 Instead, make copies of the our local variables and
4001 pass the copies by reference, then copy them back afterward. */
4002 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4003 enum tree_code xresultcode = resultcode;
4005 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4007 return cp_convert (boolean_type_node, val);
4008 op0 = xop0, op1 = xop1;
4010 resultcode = xresultcode;
4013 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4014 && warn_sign_compare
4015 /* Do not warn until the template is instantiated; we cannot
4016 bound the ranges of the arguments until that point. */
4017 && !processing_template_decl
4018 && (complain & tf_warning))
4020 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4021 result_type, resultcode);
4025 /* Issue warnings about peculiar, but valid, uses of NULL. */
4026 if ((orig_op0 == null_node || orig_op1 == null_node)
4027 /* It's reasonable to use pointer values as operands of &&
4028 and ||, so NULL is no exception. */
4029 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
4030 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
4031 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
4032 && code != EQ_EXPR && code != NE_EXPR)
4033 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
4034 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
4035 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
4036 && (complain & tf_warning))
4037 /* Some sort of arithmetic operation involving NULL was
4038 performed. Note that pointer-difference and pointer-addition
4039 have already been handled above, and so we don't end up here in
4041 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
4044 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4045 Then the expression will be built.
4046 It will be given type FINAL_TYPE if that is nonzero;
4047 otherwise, it will be given type RESULT_TYPE. */
4050 if (TREE_TYPE (op0) != result_type)
4051 op0 = cp_convert_and_check (result_type, op0);
4052 if (TREE_TYPE (op1) != result_type)
4053 op1 = cp_convert_and_check (result_type, op1);
4055 if (op0 == error_mark_node || op1 == error_mark_node)
4056 return error_mark_node;
4059 if (build_type == NULL_TREE)
4060 build_type = result_type;
4062 result = build2 (resultcode, build_type, op0, op1);
4063 result = fold_if_not_in_template (result);
4064 if (final_type != 0)
4065 result = cp_convert (final_type, result);
4067 if (TREE_OVERFLOW_P (result)
4068 && !TREE_OVERFLOW_P (op0)
4069 && !TREE_OVERFLOW_P (op1))
4070 overflow_warning (result);
4075 /* Return a tree for the sum or difference (RESULTCODE says which)
4076 of pointer PTROP and integer INTOP. */
4079 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4081 tree res_type = TREE_TYPE (ptrop);
4083 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4084 in certain circumstance (when it's valid to do so). So we need
4085 to make sure it's complete. We don't need to check here, if we
4086 can actually complete it at all, as those checks will be done in
4087 pointer_int_sum() anyway. */
4088 complete_type (TREE_TYPE (res_type));
4090 return pointer_int_sum (resultcode, ptrop,
4091 fold_if_not_in_template (intop));
4094 /* Return a tree for the difference of pointers OP0 and OP1.
4095 The resulting tree has type int. */
4098 pointer_diff (tree op0, tree op1, tree ptrtype)
4101 tree restype = ptrdiff_type_node;
4102 tree target_type = TREE_TYPE (ptrtype);
4104 if (!complete_type_or_else (target_type, NULL_TREE))
4105 return error_mark_node;
4107 if (TREE_CODE (target_type) == VOID_TYPE)
4108 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4109 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4110 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4111 if (TREE_CODE (target_type) == METHOD_TYPE)
4112 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4114 /* First do the subtraction as integers;
4115 then drop through to build the divide operator. */
4117 op0 = cp_build_binary_op (input_location,
4119 cp_convert (restype, op0),
4120 cp_convert (restype, op1),
4121 tf_warning_or_error);
4123 /* This generates an error if op1 is a pointer to an incomplete type. */
4124 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4125 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4127 op1 = (TYPE_PTROB_P (ptrtype)
4128 ? size_in_bytes (target_type)
4129 : integer_one_node);
4131 /* Do the division. */
4133 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4134 return fold_if_not_in_template (result);
4137 /* Construct and perhaps optimize a tree representation
4138 for a unary operation. CODE, a tree_code, specifies the operation
4139 and XARG is the operand. */
4142 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4144 tree orig_expr = xarg;
4148 if (processing_template_decl)
4150 if (type_dependent_expression_p (xarg))
4151 return build_min_nt (code, xarg, NULL_TREE);
4153 xarg = build_non_dependent_expr (xarg);
4158 /* [expr.unary.op] says:
4160 The address of an object of incomplete type can be taken.
4162 (And is just the ordinary address operator, not an overloaded
4163 "operator &".) However, if the type is a template
4164 specialization, we must complete the type at this point so that
4165 an overloaded "operator &" will be available if required. */
4166 if (code == ADDR_EXPR
4167 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4168 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4169 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4170 || (TREE_CODE (xarg) == OFFSET_REF)))
4171 /* Don't look for a function. */;
4173 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4174 /*overloaded_p=*/NULL, complain);
4175 if (!exp && code == ADDR_EXPR)
4177 if (is_overloaded_fn (xarg))
4179 tree fn = get_first_fn (xarg);
4180 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4183 (DECL_CONSTRUCTOR_P (fn) ? "constructor" : "destructor");
4184 error ("taking address of %s %qE", type, xarg);
4185 return error_mark_node;
4189 /* A pointer to member-function can be formed only by saying
4191 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4192 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4194 if (TREE_CODE (xarg) != OFFSET_REF
4195 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4197 error ("invalid use of %qE to form a pointer-to-member-function",
4199 if (TREE_CODE (xarg) != OFFSET_REF)
4200 inform (input_location, " a qualified-id is required");
4201 return error_mark_node;
4205 error ("parentheses around %qE cannot be used to form a"
4206 " pointer-to-member-function",
4208 PTRMEM_OK_P (xarg) = 1;
4212 if (TREE_CODE (xarg) == OFFSET_REF)
4214 ptrmem = PTRMEM_OK_P (xarg);
4216 if (!ptrmem && !flag_ms_extensions
4217 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4219 /* A single non-static member, make sure we don't allow a
4220 pointer-to-member. */
4221 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4222 TREE_OPERAND (xarg, 0),
4223 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4224 PTRMEM_OK_P (xarg) = ptrmem;
4227 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4228 warning (0, "taking address of temporary");
4229 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4232 if (processing_template_decl && exp != error_mark_node)
4233 exp = build_min_non_dep (code, exp, orig_expr,
4234 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4235 if (TREE_CODE (exp) == ADDR_EXPR)
4236 PTRMEM_OK_P (exp) = ptrmem;
4240 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4241 constants, where a null value is represented by an INTEGER_CST of
4245 cp_truthvalue_conversion (tree expr)
4247 tree type = TREE_TYPE (expr);
4248 if (TYPE_PTRMEM_P (type))
4249 return build_binary_op (EXPR_LOCATION (expr),
4250 NE_EXPR, expr, integer_zero_node, 1);
4252 return c_common_truthvalue_conversion (input_location, expr);
4255 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4258 condition_conversion (tree expr)
4261 if (processing_template_decl)
4263 t = perform_implicit_conversion (boolean_type_node, expr,
4264 tf_warning_or_error);
4265 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4269 /* Return an ADDR_EXPR giving the address of T. This function
4270 attempts no optimizations or simplifications; it is a low-level
4274 build_address (tree t)
4278 if (error_operand_p (t) || !cxx_mark_addressable (t))
4279 return error_mark_node;
4281 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4286 /* Return a NOP_EXPR converting EXPR to TYPE. */
4289 build_nop (tree type, tree expr)
4291 if (type == error_mark_node || error_operand_p (expr))
4293 return build1 (NOP_EXPR, type, expr);
4296 /* C++: Must handle pointers to members.
4298 Perhaps type instantiation should be extended to handle conversion
4299 from aggregates to types we don't yet know we want? (Or are those
4300 cases typically errors which should be reported?)
4302 NOCONVERT nonzero suppresses the default promotions
4303 (such as from short to int). */
4306 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4307 tsubst_flags_t complain)
4309 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4312 const char *errstring = NULL;
4314 const char *invalid_op_diag;
4316 if (error_operand_p (arg))
4317 return error_mark_node;
4319 if ((invalid_op_diag
4320 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4325 error (invalid_op_diag);
4326 return error_mark_node;
4331 case UNARY_PLUS_EXPR:
4334 int flags = WANT_ARITH | WANT_ENUM;
4335 /* Unary plus (but not unary minus) is allowed on pointers. */
4336 if (code == UNARY_PLUS_EXPR)
4337 flags |= WANT_POINTER;
4338 arg = build_expr_type_conversion (flags, arg, true);
4340 errstring = (code == NEGATE_EXPR
4341 ? "wrong type argument to unary minus"
4342 : "wrong type argument to unary plus");
4345 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4346 arg = perform_integral_promotions (arg);
4348 /* Make sure the result is not an lvalue: a unary plus or minus
4349 expression is always a rvalue. */
4356 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4360 arg = default_conversion (arg);
4362 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4365 errstring = "wrong type argument to bit-complement";
4366 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4367 arg = perform_integral_promotions (arg);
4371 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4372 errstring = "wrong type argument to abs";
4373 else if (!noconvert)
4374 arg = default_conversion (arg);
4378 /* Conjugating a real value is a no-op, but allow it anyway. */
4379 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4380 errstring = "wrong type argument to conjugation";
4381 else if (!noconvert)
4382 arg = default_conversion (arg);
4385 case TRUTH_NOT_EXPR:
4386 arg = perform_implicit_conversion (boolean_type_node, arg,
4388 val = invert_truthvalue (arg);
4389 if (arg != error_mark_node)
4391 errstring = "in argument to unary !";
4398 if (TREE_CODE (arg) == COMPLEX_CST)
4399 return TREE_REALPART (arg);
4400 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4402 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4403 return fold_if_not_in_template (arg);
4409 if (TREE_CODE (arg) == COMPLEX_CST)
4410 return TREE_IMAGPART (arg);
4411 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4413 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4414 return fold_if_not_in_template (arg);
4417 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4419 case PREINCREMENT_EXPR:
4420 case POSTINCREMENT_EXPR:
4421 case PREDECREMENT_EXPR:
4422 case POSTDECREMENT_EXPR:
4423 /* Handle complex lvalues (when permitted)
4424 by reduction to simpler cases. */
4426 val = unary_complex_lvalue (code, arg);
4430 /* Increment or decrement the real part of the value,
4431 and don't change the imaginary part. */
4432 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4436 arg = stabilize_reference (arg);
4437 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4438 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4439 real = cp_build_unary_op (code, real, 1, complain);
4440 if (real == error_mark_node || imag == error_mark_node)
4441 return error_mark_node;
4442 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4446 /* Report invalid types. */
4448 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4451 if (code == PREINCREMENT_EXPR)
4452 errstring ="no pre-increment operator for type";
4453 else if (code == POSTINCREMENT_EXPR)
4454 errstring ="no post-increment operator for type";
4455 else if (code == PREDECREMENT_EXPR)
4456 errstring ="no pre-decrement operator for type";
4458 errstring ="no post-decrement operator for type";
4461 else if (arg == error_mark_node)
4462 return error_mark_node;
4464 /* Report something read-only. */
4466 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4467 || TREE_READONLY (arg))
4469 if (complain & tf_error)
4470 readonly_error (arg, ((code == PREINCREMENT_EXPR
4471 || code == POSTINCREMENT_EXPR)
4472 ? "increment" : "decrement"));
4474 return error_mark_node;
4479 tree declared_type = unlowered_expr_type (arg);
4481 argtype = TREE_TYPE (arg);
4483 /* ARM $5.2.5 last annotation says this should be forbidden. */
4484 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4486 if (complain & tf_error)
4487 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4488 ? G_("ISO C++ forbids incrementing an enum")
4489 : G_("ISO C++ forbids decrementing an enum"));
4491 return error_mark_node;
4494 /* Compute the increment. */
4496 if (TREE_CODE (argtype) == POINTER_TYPE)
4498 tree type = complete_type (TREE_TYPE (argtype));
4500 if (!COMPLETE_OR_VOID_TYPE_P (type))
4502 if (complain & tf_error)
4503 error (((code == PREINCREMENT_EXPR
4504 || code == POSTINCREMENT_EXPR))
4505 ? G_("cannot increment a pointer to incomplete type %qT")
4506 : G_("cannot decrement a pointer to incomplete type %qT"),
4507 TREE_TYPE (argtype));
4509 return error_mark_node;
4511 else if ((pedantic || warn_pointer_arith)
4512 && !TYPE_PTROB_P (argtype))
4514 if (complain & tf_error)
4515 permerror (input_location, (code == PREINCREMENT_EXPR
4516 || code == POSTINCREMENT_EXPR)
4517 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4518 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4521 return error_mark_node;
4524 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4527 inc = integer_one_node;
4529 inc = cp_convert (argtype, inc);
4531 /* Complain about anything else that is not a true lvalue. */
4532 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4533 || code == POSTINCREMENT_EXPR)
4534 ? lv_increment : lv_decrement),
4536 return error_mark_node;
4538 /* Forbid using -- on `bool'. */
4539 if (same_type_p (declared_type, boolean_type_node))
4541 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4543 if (complain & tf_error)
4544 error ("invalid use of Boolean expression as operand "
4545 "to %<operator--%>");
4546 return error_mark_node;
4548 val = boolean_increment (code, arg);
4551 val = build2 (code, TREE_TYPE (arg), arg, inc);
4553 TREE_SIDE_EFFECTS (val) = 1;
4558 /* Note that this operation never does default_conversion
4559 regardless of NOCONVERT. */
4561 argtype = lvalue_type (arg);
4563 if (TREE_CODE (arg) == OFFSET_REF)
4566 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4568 tree type = build_pointer_type (TREE_TYPE (argtype));
4569 arg = build1 (CONVERT_EXPR, type, arg);
4572 else if (pedantic && DECL_MAIN_P (arg))
4575 /* Apparently a lot of autoconf scripts for C++ packages do this,
4576 so only complain if -pedantic. */
4577 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4578 pedwarn (input_location, OPT_pedantic,
4579 "ISO C++ forbids taking address of function %<::main%>");
4580 else if (flag_pedantic_errors)
4581 return error_mark_node;
4584 /* Let &* cancel out to simplify resulting code. */
4585 if (TREE_CODE (arg) == INDIRECT_REF)
4587 /* We don't need to have `current_class_ptr' wrapped in a
4588 NON_LVALUE_EXPR node. */
4589 if (arg == current_class_ref)
4590 return current_class_ptr;
4592 arg = TREE_OPERAND (arg, 0);
4593 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4595 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4596 arg = build1 (CONVERT_EXPR, type, arg);
4599 /* Don't let this be an lvalue. */
4604 /* Uninstantiated types are all functions. Taking the
4605 address of a function is a no-op, so just return the
4608 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4609 || !IDENTIFIER_OPNAME_P (arg));
4611 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4612 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4614 /* They're trying to take the address of a unique non-static
4615 member function. This is ill-formed (except in MS-land),
4616 but let's try to DTRT.
4617 Note: We only handle unique functions here because we don't
4618 want to complain if there's a static overload; non-unique
4619 cases will be handled by instantiate_type. But we need to
4620 handle this case here to allow casts on the resulting PMF.
4621 We could defer this in non-MS mode, but it's easier to give
4622 a useful error here. */
4624 /* Inside constant member functions, the `this' pointer
4625 contains an extra const qualifier. TYPE_MAIN_VARIANT
4626 is used here to remove this const from the diagnostics
4627 and the created OFFSET_REF. */
4628 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4629 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4632 if (! flag_ms_extensions)
4634 tree name = DECL_NAME (fn);
4635 if (!(complain & tf_error))
4636 return error_mark_node;
4637 else if (current_class_type
4638 && TREE_OPERAND (arg, 0) == current_class_ref)
4639 /* An expression like &memfn. */
4640 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4641 " or parenthesized non-static member function to form"
4642 " a pointer to member function. Say %<&%T::%D%>",
4645 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4646 " function to form a pointer to member function."
4650 arg = build_offset_ref (base, fn, /*address_p=*/true);
4654 if (type_unknown_p (arg))
4655 return build1 (ADDR_EXPR, unknown_type_node, arg);
4657 /* Handle complex lvalues (when permitted)
4658 by reduction to simpler cases. */
4659 val = unary_complex_lvalue (code, arg);
4663 switch (TREE_CODE (arg))
4667 case FIX_TRUNC_EXPR:
4668 /* Even if we're not being pedantic, we cannot allow this
4669 extension when we're instantiating in a SFINAE
4671 if (! lvalue_p (arg) && complain == tf_none)
4673 if (complain & tf_error)
4674 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4676 return error_mark_node;
4681 arg = BASELINK_FUNCTIONS (arg);
4685 arg = OVL_CURRENT (arg);
4689 /* Turn a reference to a non-static data member into a
4690 pointer-to-member. */
4695 if (!PTRMEM_OK_P (arg))
4696 return cp_build_unary_op (code, arg, 0, complain);
4698 t = TREE_OPERAND (arg, 1);
4699 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4701 if (complain & tf_error)
4702 error ("cannot create pointer to reference member %qD", t);
4703 return error_mark_node;
4706 type = build_ptrmem_type (context_for_name_lookup (t),
4708 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4716 /* Anything not already handled and not a true memory reference
4718 if (TREE_CODE (argtype) != FUNCTION_TYPE
4719 && TREE_CODE (argtype) != METHOD_TYPE
4720 && TREE_CODE (arg) != OFFSET_REF
4721 && !lvalue_or_else (arg, lv_addressof, complain))
4722 return error_mark_node;
4724 if (argtype != error_mark_node)
4725 argtype = build_pointer_type (argtype);
4727 /* In a template, we are processing a non-dependent expression
4728 so we can just form an ADDR_EXPR with the correct type. */
4729 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4731 val = build_address (arg);
4732 if (TREE_CODE (arg) == OFFSET_REF)
4733 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4735 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4737 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4739 /* We can only get here with a single static member
4741 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4742 && DECL_STATIC_FUNCTION_P (fn));
4744 val = build_address (fn);
4745 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4746 /* Do not lose object's side effects. */
4747 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4748 TREE_OPERAND (arg, 0), val);
4750 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4752 if (complain & tf_error)
4753 error ("attempt to take address of bit-field structure member %qD",
4754 TREE_OPERAND (arg, 1));
4755 return error_mark_node;
4759 tree object = TREE_OPERAND (arg, 0);
4760 tree field = TREE_OPERAND (arg, 1);
4761 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4762 (TREE_TYPE (object), decl_type_context (field)));
4763 val = build_address (arg);
4766 if (TREE_CODE (argtype) == POINTER_TYPE
4767 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4769 build_ptrmemfunc_type (argtype);
4770 val = build_ptrmemfunc (argtype, val, 0,
4771 /*c_cast_p=*/false);
4783 argtype = TREE_TYPE (arg);
4784 return fold_if_not_in_template (build1 (code, argtype, arg));
4787 if (complain & tf_error)
4788 error ("%s", errstring);
4789 return error_mark_node;
4792 /* Hook for the c-common bits that build a unary op. */
4794 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4795 enum tree_code code, tree xarg, int noconvert)
4797 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4800 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4801 for certain kinds of expressions which are not really lvalues
4802 but which we can accept as lvalues.
4804 If ARG is not a kind of expression we can handle, return
4808 unary_complex_lvalue (enum tree_code code, tree arg)
4810 /* Inside a template, making these kinds of adjustments is
4811 pointless; we are only concerned with the type of the
4813 if (processing_template_decl)
4816 /* Handle (a, b) used as an "lvalue". */
4817 if (TREE_CODE (arg) == COMPOUND_EXPR)
4819 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4820 tf_warning_or_error);
4821 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4822 TREE_OPERAND (arg, 0), real_result);
4825 /* Handle (a ? b : c) used as an "lvalue". */
4826 if (TREE_CODE (arg) == COND_EXPR
4827 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4828 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4830 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4831 if (TREE_CODE (arg) == MODIFY_EXPR
4832 || TREE_CODE (arg) == PREINCREMENT_EXPR
4833 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4835 tree lvalue = TREE_OPERAND (arg, 0);
4836 if (TREE_SIDE_EFFECTS (lvalue))
4838 lvalue = stabilize_reference (lvalue);
4839 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4840 lvalue, TREE_OPERAND (arg, 1));
4842 return unary_complex_lvalue
4843 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4846 if (code != ADDR_EXPR)
4849 /* Handle (a = b) used as an "lvalue" for `&'. */
4850 if (TREE_CODE (arg) == MODIFY_EXPR
4851 || TREE_CODE (arg) == INIT_EXPR)
4853 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4854 tf_warning_or_error);
4855 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4857 TREE_NO_WARNING (arg) = 1;
4861 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4862 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4863 || TREE_CODE (arg) == OFFSET_REF)
4866 /* We permit compiler to make function calls returning
4867 objects of aggregate type look like lvalues. */
4871 if (TREE_CODE (targ) == SAVE_EXPR)
4872 targ = TREE_OPERAND (targ, 0);
4874 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4876 if (TREE_CODE (arg) == SAVE_EXPR)
4879 targ = build_cplus_new (TREE_TYPE (arg), arg);
4880 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4883 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4884 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4885 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4888 /* Don't let anything else be handled specially. */
4892 /* Mark EXP saying that we need to be able to take the
4893 address of it; it should not be allocated in a register.
4894 Value is true if successful.
4896 C++: we do not allow `current_class_ptr' to be addressable. */
4899 cxx_mark_addressable (tree exp)
4904 switch (TREE_CODE (x))
4911 x = TREE_OPERAND (x, 0);
4915 if (x == current_class_ptr)
4917 error ("cannot take the address of %<this%>, which is an rvalue expression");
4918 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4924 /* Caller should not be trying to mark initialized
4925 constant fields addressable. */
4926 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4927 || DECL_IN_AGGR_P (x) == 0
4929 || DECL_EXTERNAL (x));
4934 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4935 && !DECL_ARTIFICIAL (x))
4937 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4940 ("address of explicit register variable %qD requested", x);
4943 else if (extra_warnings)
4945 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4947 TREE_ADDRESSABLE (x) = 1;
4951 TREE_ADDRESSABLE (x) = 1;
4955 TREE_ADDRESSABLE (x) = 1;
4959 TREE_ADDRESSABLE (x) = 1;
4960 cxx_mark_addressable (TREE_OPERAND (x, 0));
4968 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4971 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4972 tsubst_flags_t complain)
4974 tree orig_ifexp = ifexp;
4975 tree orig_op1 = op1;
4976 tree orig_op2 = op2;
4979 if (processing_template_decl)
4981 /* The standard says that the expression is type-dependent if
4982 IFEXP is type-dependent, even though the eventual type of the
4983 expression doesn't dependent on IFEXP. */
4984 if (type_dependent_expression_p (ifexp)
4985 /* As a GNU extension, the middle operand may be omitted. */
4986 || (op1 && type_dependent_expression_p (op1))
4987 || type_dependent_expression_p (op2))
4988 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4989 ifexp = build_non_dependent_expr (ifexp);
4991 op1 = build_non_dependent_expr (op1);
4992 op2 = build_non_dependent_expr (op2);
4995 expr = build_conditional_expr (ifexp, op1, op2, complain);
4996 if (processing_template_decl && expr != error_mark_node)
4997 return build_min_non_dep (COND_EXPR, expr,
4998 orig_ifexp, orig_op1, orig_op2);
5002 /* Given a list of expressions, return a compound expression
5003 that performs them all and returns the value of the last of them. */
5005 tree build_x_compound_expr_from_list (tree list, const char *msg)
5007 tree expr = TREE_VALUE (list);
5009 if (TREE_CHAIN (list))
5012 permerror (input_location, "%s expression list treated as compound expression", msg);
5014 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5015 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5016 tf_warning_or_error);
5022 /* Like build_x_compound_expr_from_list, but using a VEC. */
5025 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5027 if (VEC_empty (tree, vec))
5029 else if (VEC_length (tree, vec) == 1)
5030 return VEC_index (tree, vec, 0);
5038 permerror (input_location,
5039 "%s expression list treated as compound expression",
5042 expr = VEC_index (tree, vec, 0);
5043 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5044 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5050 /* Handle overloading of the ',' operator when needed. */
5053 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5056 tree orig_op1 = op1;
5057 tree orig_op2 = op2;
5059 if (processing_template_decl)
5061 if (type_dependent_expression_p (op1)
5062 || type_dependent_expression_p (op2))
5063 return build_min_nt (COMPOUND_EXPR, op1, op2);
5064 op1 = build_non_dependent_expr (op1);
5065 op2 = build_non_dependent_expr (op2);
5068 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5069 /*overloaded_p=*/NULL, complain);
5071 result = cp_build_compound_expr (op1, op2, complain);
5073 if (processing_template_decl && result != error_mark_node)
5074 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5079 /* Like cp_build_compound_expr, but for the c-common bits. */
5082 build_compound_expr (tree lhs, tree rhs)
5084 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5087 /* Build a compound expression. */
5090 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5092 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5094 if (lhs == error_mark_node || rhs == error_mark_node)
5095 return error_mark_node;
5097 if (TREE_CODE (rhs) == TARGET_EXPR)
5099 /* If the rhs is a TARGET_EXPR, then build the compound
5100 expression inside the target_expr's initializer. This
5101 helps the compiler to eliminate unnecessary temporaries. */
5102 tree init = TREE_OPERAND (rhs, 1);
5104 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5105 TREE_OPERAND (rhs, 1) = init;
5110 if (type_unknown_p (rhs))
5112 error ("no context to resolve type of %qE", rhs);
5113 return error_mark_node;
5116 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5119 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5120 casts away constness. CAST gives the type of cast.
5122 ??? This function warns for casting away any qualifier not just
5123 const. We would like to specify exactly what qualifiers are casted
5128 check_for_casting_away_constness (tree src_type, tree dest_type,
5129 enum tree_code cast)
5131 /* C-style casts are allowed to cast away constness. With
5132 WARN_CAST_QUAL, we still want to issue a warning. */
5133 if (cast == CAST_EXPR && !warn_cast_qual)
5136 if (!casts_away_constness (src_type, dest_type))
5142 warning (OPT_Wcast_qual,
5143 "cast from type %qT to type %qT casts away qualifiers",
5144 src_type, dest_type);
5147 case STATIC_CAST_EXPR:
5148 error ("static_cast from type %qT to type %qT casts away qualifiers",
5149 src_type, dest_type);
5152 case REINTERPRET_CAST_EXPR:
5153 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5154 src_type, dest_type);
5161 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5162 (another pointer-to-member type in the same hierarchy) and return
5163 the converted expression. If ALLOW_INVERSE_P is permitted, a
5164 pointer-to-derived may be converted to pointer-to-base; otherwise,
5165 only the other direction is permitted. If C_CAST_P is true, this
5166 conversion is taking place as part of a C-style cast. */
5169 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5172 if (TYPE_PTRMEM_P (type))
5176 if (TREE_CODE (expr) == PTRMEM_CST)
5177 expr = cplus_expand_constant (expr);
5178 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5179 TYPE_PTRMEM_CLASS_TYPE (type),
5182 if (!integer_zerop (delta))
5184 tree cond, op1, op2;
5186 cond = cp_build_binary_op (input_location,
5189 build_int_cst (TREE_TYPE (expr), -1),
5190 tf_warning_or_error);
5191 op1 = build_nop (ptrdiff_type_node, expr);
5192 op2 = cp_build_binary_op (input_location,
5193 PLUS_EXPR, op1, delta,
5194 tf_warning_or_error);
5196 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5200 return build_nop (type, expr);
5203 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5204 allow_inverse_p, c_cast_p);
5207 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5208 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5209 Otherwise, return EXPR unchanged. */
5212 ignore_overflows (tree expr, tree orig)
5214 if (TREE_CODE (expr) == INTEGER_CST
5215 && CONSTANT_CLASS_P (orig)
5216 && TREE_CODE (orig) != STRING_CST
5217 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5219 if (!TREE_OVERFLOW (orig))
5220 /* Ensure constant sharing. */
5221 expr = build_int_cst_wide (TREE_TYPE (expr),
5222 TREE_INT_CST_LOW (expr),
5223 TREE_INT_CST_HIGH (expr));
5226 /* Avoid clobbering a shared constant. */
5227 expr = copy_node (expr);
5228 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5234 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5235 this static_cast is being attempted as one of the possible casts
5236 allowed by a C-style cast. (In that case, accessibility of base
5237 classes is not considered, and it is OK to cast away
5238 constness.) Return the result of the cast. *VALID_P is set to
5239 indicate whether or not the cast was valid. */
5242 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5243 bool *valid_p, tsubst_flags_t complain)
5249 /* Assume the cast is valid. */
5252 intype = TREE_TYPE (expr);
5254 /* Save casted types in the function's used types hash table. */
5255 used_types_insert (type);
5257 /* [expr.static.cast]
5259 An lvalue of type "cv1 B", where B is a class type, can be cast
5260 to type "reference to cv2 D", where D is a class derived (clause
5261 _class.derived_) from B, if a valid standard conversion from
5262 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5263 same cv-qualification as, or greater cv-qualification than, cv1,
5264 and B is not a virtual base class of D. */
5265 /* We check this case before checking the validity of "TYPE t =
5266 EXPR;" below because for this case:
5269 struct D : public B { D(const B&); };
5271 void f() { static_cast<const D&>(b); }
5273 we want to avoid constructing a new D. The standard is not
5274 completely clear about this issue, but our interpretation is
5275 consistent with other compilers. */
5276 if (TREE_CODE (type) == REFERENCE_TYPE
5277 && CLASS_TYPE_P (TREE_TYPE (type))
5278 && CLASS_TYPE_P (intype)
5279 && real_lvalue_p (expr)
5280 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5281 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5282 build_pointer_type (TYPE_MAIN_VARIANT
5283 (TREE_TYPE (type))))
5285 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5289 /* There is a standard conversion from "D*" to "B*" even if "B"
5290 is ambiguous or inaccessible. If this is really a
5291 static_cast, then we check both for inaccessibility and
5292 ambiguity. However, if this is a static_cast being performed
5293 because the user wrote a C-style cast, then accessibility is
5295 base = lookup_base (TREE_TYPE (type), intype,
5296 c_cast_p ? ba_unique : ba_check,
5299 /* Convert from "B*" to "D*". This function will check that "B"
5300 is not a virtual base of "D". */
5301 expr = build_base_path (MINUS_EXPR, build_address (expr),
5302 base, /*nonnull=*/false);
5303 /* Convert the pointer to a reference -- but then remember that
5304 there are no expressions with reference type in C++. */
5305 return convert_from_reference (build_nop (type, expr));
5310 /* [expr.static.cast]
5312 An expression e can be explicitly converted to a type T using a
5313 static_cast of the form static_cast<T>(e) if the declaration T
5314 t(e);" is well-formed, for some invented temporary variable
5316 result = perform_direct_initialization_if_possible (type, expr,
5317 c_cast_p, complain);
5320 result = convert_from_reference (result);
5322 /* Ignore any integer overflow caused by the cast. */
5323 result = ignore_overflows (result, orig);
5325 /* [expr.static.cast]
5327 If T is a reference type, the result is an lvalue; otherwise,
5328 the result is an rvalue. */
5329 if (TREE_CODE (type) != REFERENCE_TYPE)
5330 result = rvalue (result);
5334 /* [expr.static.cast]
5336 Any expression can be explicitly converted to type cv void. */
5337 if (TREE_CODE (type) == VOID_TYPE)
5338 return convert_to_void (expr, /*implicit=*/NULL, complain);
5340 /* [expr.static.cast]
5342 The inverse of any standard conversion sequence (clause _conv_),
5343 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5344 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5345 (_conv.bool_) conversions, can be performed explicitly using
5346 static_cast subject to the restriction that the explicit
5347 conversion does not cast away constness (_expr.const.cast_), and
5348 the following additional rules for specific cases: */
5349 /* For reference, the conversions not excluded are: integral
5350 promotions, floating point promotion, integral conversions,
5351 floating point conversions, floating-integral conversions,
5352 pointer conversions, and pointer to member conversions. */
5355 A value of integral _or enumeration_ type can be explicitly
5356 converted to an enumeration type. */
5357 /* The effect of all that is that any conversion between any two
5358 types which are integral, floating, or enumeration types can be
5360 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5361 || SCALAR_FLOAT_TYPE_P (type))
5362 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5363 || SCALAR_FLOAT_TYPE_P (intype)))
5365 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5367 /* Ignore any integer overflow caused by the cast. */
5368 expr = ignore_overflows (expr, orig);
5372 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5373 && CLASS_TYPE_P (TREE_TYPE (type))
5374 && CLASS_TYPE_P (TREE_TYPE (intype))
5375 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5376 (TREE_TYPE (intype))),
5377 build_pointer_type (TYPE_MAIN_VARIANT
5378 (TREE_TYPE (type)))))
5383 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5384 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5385 c_cast_p ? ba_unique : ba_check,
5387 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5390 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5391 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5398 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5399 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5401 if (TYPE_PTRMEM_P (type))
5403 t1 = (build_ptrmem_type
5405 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5406 t2 = (build_ptrmem_type
5408 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5415 if (can_convert (t1, t2) || can_convert (t2, t1))
5418 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5419 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5424 /* [expr.static.cast]
5426 An rvalue of type "pointer to cv void" can be explicitly
5427 converted to a pointer to object type. A value of type pointer
5428 to object converted to "pointer to cv void" and back to the
5429 original pointer type will have its original value. */
5430 if (TREE_CODE (intype) == POINTER_TYPE
5431 && VOID_TYPE_P (TREE_TYPE (intype))
5432 && TYPE_PTROB_P (type))
5435 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5436 return build_nop (type, expr);
5440 return error_mark_node;
5443 /* Return an expression representing static_cast<TYPE>(EXPR). */
5446 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5451 if (type == error_mark_node || expr == error_mark_node)
5452 return error_mark_node;
5454 if (processing_template_decl)
5456 expr = build_min (STATIC_CAST_EXPR, type, expr);
5457 /* We don't know if it will or will not have side effects. */
5458 TREE_SIDE_EFFECTS (expr) = 1;
5459 return convert_from_reference (expr);
5462 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5463 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5464 if (TREE_CODE (type) != REFERENCE_TYPE
5465 && TREE_CODE (expr) == NOP_EXPR
5466 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5467 expr = TREE_OPERAND (expr, 0);
5469 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5474 if (complain & tf_error)
5475 error ("invalid static_cast from type %qT to type %qT",
5476 TREE_TYPE (expr), type);
5477 return error_mark_node;
5480 /* EXPR is an expression with member function or pointer-to-member
5481 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5482 not permitted by ISO C++, but we accept it in some modes. If we
5483 are not in one of those modes, issue a diagnostic. Return the
5484 converted expression. */
5487 convert_member_func_to_ptr (tree type, tree expr)
5492 intype = TREE_TYPE (expr);
5493 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5494 || TREE_CODE (intype) == METHOD_TYPE);
5496 if (pedantic || warn_pmf2ptr)
5497 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5498 "converting from %qT to %qT", intype, type);
5500 if (TREE_CODE (intype) == METHOD_TYPE)
5501 expr = build_addr_func (expr);
5502 else if (TREE_CODE (expr) == PTRMEM_CST)
5503 expr = build_address (PTRMEM_CST_MEMBER (expr));
5506 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5507 decl = build_address (decl);
5508 expr = get_member_function_from_ptrfunc (&decl, expr);
5511 return build_nop (type, expr);
5514 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5515 If C_CAST_P is true, this reinterpret cast is being done as part of
5516 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5517 indicate whether or not reinterpret_cast was valid. */
5520 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5521 bool *valid_p, tsubst_flags_t complain)
5525 /* Assume the cast is invalid. */
5529 if (type == error_mark_node || error_operand_p (expr))
5530 return error_mark_node;
5532 intype = TREE_TYPE (expr);
5534 /* Save casted types in the function's used types hash table. */
5535 used_types_insert (type);
5537 /* [expr.reinterpret.cast]
5538 An lvalue expression of type T1 can be cast to the type
5539 "reference to T2" if an expression of type "pointer to T1" can be
5540 explicitly converted to the type "pointer to T2" using a
5541 reinterpret_cast. */
5542 if (TREE_CODE (type) == REFERENCE_TYPE)
5544 if (! real_lvalue_p (expr))
5546 if (complain & tf_error)
5547 error ("invalid cast of an rvalue expression of type "
5550 return error_mark_node;
5553 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5554 "B" are related class types; the reinterpret_cast does not
5555 adjust the pointer. */
5556 if (TYPE_PTR_P (intype)
5557 && (complain & tf_warning)
5558 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5559 COMPARE_BASE | COMPARE_DERIVED)))
5560 warning (0, "casting %qT to %qT does not dereference pointer",
5563 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5564 if (expr != error_mark_node)
5565 expr = build_reinterpret_cast_1
5566 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5568 if (expr != error_mark_node)
5569 expr = cp_build_indirect_ref (expr, 0, complain);
5573 /* As a G++ extension, we consider conversions from member
5574 functions, and pointers to member functions to
5575 pointer-to-function and pointer-to-void types. If
5576 -Wno-pmf-conversions has not been specified,
5577 convert_member_func_to_ptr will issue an error message. */
5578 if ((TYPE_PTRMEMFUNC_P (intype)
5579 || TREE_CODE (intype) == METHOD_TYPE)
5580 && TYPE_PTR_P (type)
5581 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5582 || VOID_TYPE_P (TREE_TYPE (type))))
5583 return convert_member_func_to_ptr (type, expr);
5585 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5586 array-to-pointer, and function-to-pointer conversions are
5588 expr = decay_conversion (expr);
5590 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5591 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5592 if (TREE_CODE (expr) == NOP_EXPR
5593 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5594 expr = TREE_OPERAND (expr, 0);
5596 if (error_operand_p (expr))
5597 return error_mark_node;
5599 intype = TREE_TYPE (expr);
5601 /* [expr.reinterpret.cast]
5602 A pointer can be converted to any integral type large enough to
5604 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5606 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5608 if (complain & tf_error)
5609 permerror (input_location, "cast from %qT to %qT loses precision",
5612 return error_mark_node;
5615 /* [expr.reinterpret.cast]
5616 A value of integral or enumeration type can be explicitly
5617 converted to a pointer. */
5618 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5621 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5622 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5623 return fold_if_not_in_template (build_nop (type, expr));
5624 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5625 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5630 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5631 /* Warn about possible alignment problems. */
5632 if (STRICT_ALIGNMENT && warn_cast_align
5633 && (complain & tf_warning)
5634 && !VOID_TYPE_P (type)
5635 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5636 && COMPLETE_TYPE_P (TREE_TYPE (type))
5637 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5638 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5639 warning (OPT_Wcast_align, "cast from %qT to %qT "
5640 "increases required alignment of target type", intype, type);
5642 /* We need to strip nops here, because the front end likes to
5643 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5645 if (warn_strict_aliasing <= 2)
5646 strict_aliasing_warning (intype, type, sexpr);
5648 return fold_if_not_in_template (build_nop (type, expr));
5650 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5651 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5653 if (pedantic && (complain & tf_warning))
5654 /* Only issue a warning, as we have always supported this
5655 where possible, and it is necessary in some cases. DR 195
5656 addresses this issue, but as of 2004/10/26 is still in
5658 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5659 return fold_if_not_in_template (build_nop (type, expr));
5661 else if (TREE_CODE (type) == VECTOR_TYPE)
5662 return fold_if_not_in_template (convert_to_vector (type, expr));
5663 else if (TREE_CODE (intype) == VECTOR_TYPE
5664 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5665 return fold_if_not_in_template (convert_to_integer (type, expr));
5670 if (complain & tf_error)
5671 error ("invalid cast from type %qT to type %qT", intype, type);
5672 return error_mark_node;
5675 return cp_convert (type, expr);
5679 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5681 if (type == error_mark_node || expr == error_mark_node)
5682 return error_mark_node;
5684 if (processing_template_decl)
5686 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5688 if (!TREE_SIDE_EFFECTS (t)
5689 && type_dependent_expression_p (expr))
5690 /* There might turn out to be side effects inside expr. */
5691 TREE_SIDE_EFFECTS (t) = 1;
5692 return convert_from_reference (t);
5695 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5696 /*valid_p=*/NULL, complain);
5699 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5700 return an appropriate expression. Otherwise, return
5701 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5702 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5703 performing a C-style cast, its value upon return will indicate
5704 whether or not the conversion succeeded. */
5707 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5711 tree reference_type;
5713 /* Callers are responsible for handling error_mark_node as a
5714 destination type. */
5715 gcc_assert (dst_type != error_mark_node);
5716 /* In a template, callers should be building syntactic
5717 representations of casts, not using this machinery. */
5718 gcc_assert (!processing_template_decl);
5720 /* Assume the conversion is invalid. */
5724 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5727 error ("invalid use of const_cast with type %qT, "
5728 "which is not a pointer, "
5729 "reference, nor a pointer-to-data-member type", dst_type);
5730 return error_mark_node;
5733 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5736 error ("invalid use of const_cast with type %qT, which is a pointer "
5737 "or reference to a function type", dst_type);
5738 return error_mark_node;
5741 /* Save casted types in the function's used types hash table. */
5742 used_types_insert (dst_type);
5744 src_type = TREE_TYPE (expr);
5745 /* Expressions do not really have reference types. */
5746 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5747 src_type = TREE_TYPE (src_type);
5749 /* [expr.const.cast]
5751 An lvalue of type T1 can be explicitly converted to an lvalue of
5752 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5753 types) if a pointer to T1 can be explicitly converted to the type
5754 pointer to T2 using a const_cast. */
5755 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5757 reference_type = dst_type;
5758 if (! real_lvalue_p (expr))
5761 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5762 src_type, dst_type);
5763 return error_mark_node;
5765 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5766 src_type = build_pointer_type (src_type);
5770 reference_type = NULL_TREE;
5771 /* If the destination type is not a reference type, the
5772 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5773 conversions are performed. */
5774 src_type = type_decays_to (src_type);
5775 if (src_type == error_mark_node)
5776 return error_mark_node;
5779 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5780 && comp_ptr_ttypes_const (dst_type, src_type))
5785 /* This cast is actually a C-style cast. Issue a warning if
5786 the user is making a potentially unsafe cast. */
5787 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5791 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5792 complain? tf_warning_or_error : tf_none);
5793 expr = build_nop (reference_type, expr);
5794 return convert_from_reference (expr);
5798 expr = decay_conversion (expr);
5799 /* build_c_cast puts on a NOP_EXPR to make the result not an
5800 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5801 non-lvalue context. */
5802 if (TREE_CODE (expr) == NOP_EXPR
5803 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5804 expr = TREE_OPERAND (expr, 0);
5805 return build_nop (dst_type, expr);
5810 error ("invalid const_cast from type %qT to type %qT",
5811 src_type, dst_type);
5812 return error_mark_node;
5816 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5818 if (type == error_mark_node || error_operand_p (expr))
5819 return error_mark_node;
5821 if (processing_template_decl)
5823 tree t = build_min (CONST_CAST_EXPR, type, expr);
5825 if (!TREE_SIDE_EFFECTS (t)
5826 && type_dependent_expression_p (expr))
5827 /* There might turn out to be side effects inside expr. */
5828 TREE_SIDE_EFFECTS (t) = 1;
5829 return convert_from_reference (t);
5832 return build_const_cast_1 (type, expr, complain & tf_error,
5836 /* Like cp_build_c_cast, but for the c-common bits. */
5839 build_c_cast (tree type, tree expr)
5841 return cp_build_c_cast (type, expr, tf_warning_or_error);
5844 /* Build an expression representing an explicit C-style cast to type
5845 TYPE of expression EXPR. */
5848 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5854 if (type == error_mark_node || error_operand_p (expr))
5855 return error_mark_node;
5857 if (processing_template_decl)
5859 tree t = build_min (CAST_EXPR, type,
5860 tree_cons (NULL_TREE, value, NULL_TREE));
5861 /* We don't know if it will or will not have side effects. */
5862 TREE_SIDE_EFFECTS (t) = 1;
5863 return convert_from_reference (t);
5866 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5867 'Class') should always be retained, because this information aids
5868 in method lookup. */
5869 if (objc_is_object_ptr (type)
5870 && objc_is_object_ptr (TREE_TYPE (expr)))
5871 return build_nop (type, expr);
5873 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5874 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5875 if (TREE_CODE (type) != REFERENCE_TYPE
5876 && TREE_CODE (value) == NOP_EXPR
5877 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5878 value = TREE_OPERAND (value, 0);
5880 if (TREE_CODE (type) == ARRAY_TYPE)
5882 /* Allow casting from T1* to T2[] because Cfront allows it.
5883 NIHCL uses it. It is not valid ISO C++ however. */
5884 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5886 if (complain & tf_error)
5887 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5889 return error_mark_node;
5890 type = build_pointer_type (TREE_TYPE (type));
5894 if (complain & tf_error)
5895 error ("ISO C++ forbids casting to an array type %qT", type);
5896 return error_mark_node;
5900 if (TREE_CODE (type) == FUNCTION_TYPE
5901 || TREE_CODE (type) == METHOD_TYPE)
5903 if (complain & tf_error)
5904 error ("invalid cast to function type %qT", type);
5905 return error_mark_node;
5908 /* A C-style cast can be a const_cast. */
5909 result = build_const_cast_1 (type, value, /*complain=*/false,
5914 /* Or a static cast. */
5915 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5916 &valid_p, complain);
5917 /* Or a reinterpret_cast. */
5919 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5920 &valid_p, complain);
5921 /* The static_cast or reinterpret_cast may be followed by a
5924 /* A valid cast may result in errors if, for example, a
5925 conversion to am ambiguous base class is required. */
5926 && !error_operand_p (result))
5930 /* Non-class rvalues always have cv-unqualified type. */
5931 if (!CLASS_TYPE_P (type))
5932 type = TYPE_MAIN_VARIANT (type);
5933 result_type = TREE_TYPE (result);
5934 if (!CLASS_TYPE_P (result_type))
5935 result_type = TYPE_MAIN_VARIANT (result_type);
5936 /* If the type of RESULT does not match TYPE, perform a
5937 const_cast to make it match. If the static_cast or
5938 reinterpret_cast succeeded, we will differ by at most
5939 cv-qualification, so the follow-on const_cast is guaranteed
5941 if (!same_type_p (non_reference (type), non_reference (result_type)))
5943 result = build_const_cast_1 (type, result, false, &valid_p);
5944 gcc_assert (valid_p);
5949 return error_mark_node;
5952 /* For use from the C common bits. */
5954 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5955 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
5956 enum tree_code modifycode, tree rhs,
5957 tree rhs_origtype ATTRIBUTE_UNUSED)
5959 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5962 /* Build an assignment expression of lvalue LHS from value RHS.
5963 MODIFYCODE is the code for a binary operator that we use
5964 to combine the old value of LHS with RHS to get the new value.
5965 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5967 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5970 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5971 tsubst_flags_t complain)
5975 tree lhstype = TREE_TYPE (lhs);
5976 tree olhstype = lhstype;
5977 bool plain_assign = (modifycode == NOP_EXPR);
5979 /* Avoid duplicate error messages from operands that had errors. */
5980 if (error_operand_p (lhs) || error_operand_p (rhs))
5981 return error_mark_node;
5983 /* Handle control structure constructs used as "lvalues". */
5984 switch (TREE_CODE (lhs))
5986 /* Handle --foo = 5; as these are valid constructs in C++. */
5987 case PREDECREMENT_EXPR:
5988 case PREINCREMENT_EXPR:
5989 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5990 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5991 stabilize_reference (TREE_OPERAND (lhs, 0)),
5992 TREE_OPERAND (lhs, 1));
5993 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
5994 modifycode, rhs, complain);
5995 if (newrhs == error_mark_node)
5996 return error_mark_node;
5997 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5999 /* Handle (a, b) used as an "lvalue". */
6001 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6002 modifycode, rhs, complain);
6003 if (newrhs == error_mark_node)
6004 return error_mark_node;
6005 return build2 (COMPOUND_EXPR, lhstype,
6006 TREE_OPERAND (lhs, 0), newrhs);
6009 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6010 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6011 stabilize_reference (TREE_OPERAND (lhs, 0)),
6012 TREE_OPERAND (lhs, 1));
6013 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6015 if (newrhs == error_mark_node)
6016 return error_mark_node;
6017 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6021 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6022 when neither operand has side-effects. */
6023 if (!lvalue_or_else (lhs, lv_assign, complain))
6024 return error_mark_node;
6026 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6027 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6029 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6030 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6032 TREE_OPERAND (lhs, 0),
6033 TREE_OPERAND (lhs, 1)),
6034 TREE_OPERAND (lhs, 0),
6035 TREE_OPERAND (lhs, 1));
6038 /* Handle (a ? b : c) used as an "lvalue". */
6041 /* Produce (a ? (b = rhs) : (c = rhs))
6042 except that the RHS goes through a save-expr
6043 so the code to compute it is only emitted once. */
6045 tree preeval = NULL_TREE;
6047 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6049 if (complain & tf_error)
6050 error ("void value not ignored as it ought to be");
6051 return error_mark_node;
6054 rhs = stabilize_expr (rhs, &preeval);
6056 /* Check this here to avoid odd errors when trying to convert
6057 a throw to the type of the COND_EXPR. */
6058 if (!lvalue_or_else (lhs, lv_assign, complain))
6059 return error_mark_node;
6061 cond = build_conditional_expr
6062 (TREE_OPERAND (lhs, 0),
6063 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6064 modifycode, rhs, complain),
6065 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6066 modifycode, rhs, complain),
6069 if (cond == error_mark_node)
6071 /* Make sure the code to compute the rhs comes out
6072 before the split. */
6074 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6082 if (modifycode == INIT_EXPR)
6084 if (TREE_CODE (rhs) == CONSTRUCTOR)
6086 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6087 /* Call convert to generate an error; see PR 11063. */
6088 rhs = convert (lhstype, rhs);
6089 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6090 TREE_SIDE_EFFECTS (result) = 1;
6093 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6094 /* Do the default thing. */;
6097 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6098 result = build_special_member_call (lhs, complete_ctor_identifier,
6099 &rhs_vec, lhstype, LOOKUP_NORMAL,
6101 release_tree_vector (rhs_vec);
6102 if (result == NULL_TREE)
6103 return error_mark_node;
6109 lhs = require_complete_type (lhs);
6110 if (lhs == error_mark_node)
6111 return error_mark_node;
6113 if (modifycode == NOP_EXPR)
6115 /* `operator=' is not an inheritable operator. */
6116 if (! MAYBE_CLASS_TYPE_P (lhstype))
6117 /* Do the default thing. */;
6120 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6121 lhs, rhs, make_node (NOP_EXPR),
6122 /*overloaded_p=*/NULL,
6124 if (result == NULL_TREE)
6125 return error_mark_node;
6132 /* A binary op has been requested. Combine the old LHS
6133 value with the RHS producing the value we should actually
6134 store into the LHS. */
6135 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6136 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6137 || MAYBE_CLASS_TYPE_P (lhstype)));
6139 lhs = stabilize_reference (lhs);
6140 newrhs = cp_build_binary_op (input_location,
6141 modifycode, lhs, rhs,
6143 if (newrhs == error_mark_node)
6145 if (complain & tf_error)
6146 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6147 TREE_TYPE (lhs), TREE_TYPE (rhs));
6148 return error_mark_node;
6151 /* Now it looks like a plain assignment. */
6152 modifycode = NOP_EXPR;
6154 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6155 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6158 /* The left-hand side must be an lvalue. */
6159 if (!lvalue_or_else (lhs, lv_assign, complain))
6160 return error_mark_node;
6162 /* Warn about modifying something that is `const'. Don't warn if
6163 this is initialization. */
6164 if (modifycode != INIT_EXPR
6165 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6166 /* Functions are not modifiable, even though they are
6168 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6169 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6170 /* If it's an aggregate and any field is const, then it is
6171 effectively const. */
6172 || (CLASS_TYPE_P (lhstype)
6173 && C_TYPE_FIELDS_READONLY (lhstype))))
6175 if (complain & tf_error)
6176 readonly_error (lhs, "assignment");
6178 return error_mark_node;
6181 /* If storing into a structure or union member, it may have been given a
6182 lowered bitfield type. We need to convert to the declared type first,
6183 so retrieve it now. */
6185 olhstype = unlowered_expr_type (lhs);
6187 /* Convert new value to destination type. */
6189 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6193 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6194 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6196 if (complain & tf_error)
6197 error ("incompatible types in assignment of %qT to %qT",
6198 TREE_TYPE (rhs), lhstype);
6199 return error_mark_node;
6202 /* Allow array assignment in compiler-generated code. */
6203 if (!current_function_decl || !DECL_ARTIFICIAL (current_function_decl))
6205 /* This routine is used for both initialization and assignment.
6206 Make sure the diagnostic message differentiates the context. */
6207 if (complain & tf_error)
6209 if (modifycode == INIT_EXPR)
6210 error ("array used as initializer");
6212 error ("invalid array assignment");
6214 return error_mark_node;
6217 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6218 ? 1 + (modifycode != INIT_EXPR): 0;
6219 return build_vec_init (lhs, NULL_TREE, newrhs,
6220 /*explicit_value_init_p=*/false,
6221 from_array, complain);
6224 if (modifycode == INIT_EXPR)
6225 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6226 LOOKUP_ONLYCONVERTING. */
6227 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6228 "initialization", NULL_TREE, 0,
6231 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6232 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6234 if (!same_type_p (lhstype, olhstype))
6235 newrhs = cp_convert_and_check (lhstype, newrhs);
6237 if (modifycode != INIT_EXPR)
6239 if (TREE_CODE (newrhs) == CALL_EXPR
6240 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6241 newrhs = build_cplus_new (lhstype, newrhs);
6243 /* Can't initialize directly from a TARGET_EXPR, since that would
6244 cause the lhs to be constructed twice, and possibly result in
6245 accidental self-initialization. So we force the TARGET_EXPR to be
6246 expanded without a target. */
6247 if (TREE_CODE (newrhs) == TARGET_EXPR)
6248 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6249 TREE_OPERAND (newrhs, 0));
6252 if (newrhs == error_mark_node)
6253 return error_mark_node;
6255 if (c_dialect_objc () && flag_objc_gc)
6257 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6263 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6264 lhstype, lhs, newrhs);
6266 TREE_SIDE_EFFECTS (result) = 1;
6268 TREE_NO_WARNING (result) = 1;
6274 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6275 tsubst_flags_t complain)
6277 if (processing_template_decl)
6278 return build_min_nt (MODOP_EXPR, lhs,
6279 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6281 if (modifycode != NOP_EXPR)
6283 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6284 make_node (modifycode),
6285 /*overloaded_p=*/NULL,
6289 TREE_NO_WARNING (rval) = 1;
6293 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6296 /* Helper function for get_delta_difference which assumes FROM is a base
6297 class of TO. Returns a delta for the conversion of pointer-to-member
6298 of FROM to pointer-to-member of TO. If the conversion is invalid,
6299 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6300 If C_CAST_P is true, this conversion is taking place as part of a C-style
6304 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6309 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6310 if (kind == bk_inaccessible || kind == bk_ambig)
6312 error (" in pointer to member function conversion");
6313 return size_zero_node;
6317 if (kind != bk_via_virtual)
6318 return BINFO_OFFSET (binfo);
6320 /* FROM is a virtual base class of TO. Issue an error or warning
6321 depending on whether or not this is a reinterpret cast. */
6323 error ("pointer to member conversion via virtual base %qT",
6324 BINFO_TYPE (binfo_from_vbase (binfo)));
6326 return size_zero_node;
6333 /* Get difference in deltas for different pointer to member function
6334 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6335 the conversion is invalid, the constant is zero. If
6336 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6337 If C_CAST_P is true this conversion is taking place as part of a
6340 Note that the naming of FROM and TO is kind of backwards; the return
6341 value is what we add to a TO in order to get a FROM. They are named
6342 this way because we call this function to find out how to convert from
6343 a pointer to member of FROM to a pointer to member of TO. */
6346 get_delta_difference (tree from, tree to,
6347 bool allow_inverse_p,
6352 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6353 /* Pointer to member of incomplete class is permitted*/
6354 result = size_zero_node;
6356 result = get_delta_difference_1 (from, to, c_cast_p);
6360 if (!allow_inverse_p)
6362 error_not_base_type (from, to);
6363 error (" in pointer to member conversion");
6364 result = size_zero_node;
6368 result = get_delta_difference_1 (to, from, c_cast_p);
6371 result = size_diffop (size_zero_node, result);
6374 error_not_base_type (from, to);
6375 error (" in pointer to member conversion");
6376 result = size_zero_node;
6381 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6385 /* Return a constructor for the pointer-to-member-function TYPE using
6386 the other components as specified. */
6389 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6394 VEC(constructor_elt, gc) *v;
6396 /* Pull the FIELD_DECLs out of the type. */
6397 pfn_field = TYPE_FIELDS (type);
6398 delta_field = TREE_CHAIN (pfn_field);
6400 /* Make sure DELTA has the type we want. */
6401 delta = convert_and_check (delta_type_node, delta);
6403 /* Convert to the correct target type if necessary. */
6404 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6406 /* Finish creating the initializer. */
6407 v = VEC_alloc(constructor_elt, gc, 2);
6408 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6409 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6410 u = build_constructor (type, v);
6411 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6412 TREE_STATIC (u) = (TREE_CONSTANT (u)
6413 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6415 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6420 /* Build a constructor for a pointer to member function. It can be
6421 used to initialize global variables, local variable, or used
6422 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6425 If FORCE is nonzero, then force this conversion, even if
6426 we would rather not do it. Usually set when using an explicit
6427 cast. A C-style cast is being processed iff C_CAST_P is true.
6429 Return error_mark_node, if something goes wrong. */
6432 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6438 if (error_operand_p (pfn))
6439 return error_mark_node;
6441 pfn_type = TREE_TYPE (pfn);
6442 to_type = build_ptrmemfunc_type (type);
6444 /* Handle multiple conversions of pointer to member functions. */
6445 if (TYPE_PTRMEMFUNC_P (pfn_type))
6447 tree delta = NULL_TREE;
6448 tree npfn = NULL_TREE;
6452 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6453 error ("invalid conversion to type %qT from type %qT",
6456 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6457 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6461 /* We don't have to do any conversion to convert a
6462 pointer-to-member to its own type. But, we don't want to
6463 just return a PTRMEM_CST if there's an explicit cast; that
6464 cast should make the expression an invalid template argument. */
6465 if (TREE_CODE (pfn) != PTRMEM_CST)
6467 if (same_type_p (to_type, pfn_type))
6469 else if (integer_zerop (n))
6470 return build_reinterpret_cast (to_type, pfn,
6471 tf_warning_or_error);
6474 if (TREE_SIDE_EFFECTS (pfn))
6475 pfn = save_expr (pfn);
6477 /* Obtain the function pointer and the current DELTA. */
6478 if (TREE_CODE (pfn) == PTRMEM_CST)
6479 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6482 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6483 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6486 /* Just adjust the DELTA field. */
6487 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6488 (TREE_TYPE (delta), ptrdiff_type_node));
6489 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6490 n = cp_build_binary_op (input_location,
6491 LSHIFT_EXPR, n, integer_one_node,
6492 tf_warning_or_error);
6493 delta = cp_build_binary_op (input_location,
6494 PLUS_EXPR, delta, n, tf_warning_or_error);
6495 return build_ptrmemfunc1 (to_type, delta, npfn);
6498 /* Handle null pointer to member function conversions. */
6499 if (integer_zerop (pfn))
6501 pfn = build_c_cast (type, integer_zero_node);
6502 return build_ptrmemfunc1 (to_type,
6507 if (type_unknown_p (pfn))
6508 return instantiate_type (type, pfn, tf_warning_or_error);
6510 fn = TREE_OPERAND (pfn, 0);
6511 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6512 /* In a template, we will have preserved the
6514 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6515 return make_ptrmem_cst (to_type, fn);
6518 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6521 ??? There is no consistency as to the types returned for the above
6522 values. Some code acts as if it were a sizetype and some as if it were
6523 integer_type_node. */
6526 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6528 tree type = TREE_TYPE (cst);
6529 tree fn = PTRMEM_CST_MEMBER (cst);
6530 tree ptr_class, fn_class;
6532 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6534 /* The class that the function belongs to. */
6535 fn_class = DECL_CONTEXT (fn);
6537 /* The class that we're creating a pointer to member of. */
6538 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6540 /* First, calculate the adjustment to the function's class. */
6541 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6544 if (!DECL_VIRTUAL_P (fn))
6545 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6548 /* If we're dealing with a virtual function, we have to adjust 'this'
6549 again, to point to the base which provides the vtable entry for
6550 fn; the call will do the opposite adjustment. */
6551 tree orig_class = DECL_CONTEXT (fn);
6552 tree binfo = binfo_or_else (orig_class, fn_class);
6553 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6554 *delta, BINFO_OFFSET (binfo));
6555 *delta = fold_if_not_in_template (*delta);
6557 /* We set PFN to the vtable offset at which the function can be
6558 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6559 case delta is shifted left, and then incremented). */
6560 *pfn = DECL_VINDEX (fn);
6561 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6562 TYPE_SIZE_UNIT (vtable_entry_type));
6563 *pfn = fold_if_not_in_template (*pfn);
6565 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6567 case ptrmemfunc_vbit_in_pfn:
6568 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6570 *pfn = fold_if_not_in_template (*pfn);
6573 case ptrmemfunc_vbit_in_delta:
6574 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6575 *delta, integer_one_node);
6576 *delta = fold_if_not_in_template (*delta);
6577 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6578 *delta, integer_one_node);
6579 *delta = fold_if_not_in_template (*delta);
6586 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6587 *pfn = fold_if_not_in_template (*pfn);
6591 /* Return an expression for PFN from the pointer-to-member function
6595 pfn_from_ptrmemfunc (tree t)
6597 if (TREE_CODE (t) == PTRMEM_CST)
6602 expand_ptrmemfunc_cst (t, &delta, &pfn);
6607 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6610 /* Return an expression for DELTA from the pointer-to-member function
6614 delta_from_ptrmemfunc (tree t)
6616 if (TREE_CODE (t) == PTRMEM_CST)
6621 expand_ptrmemfunc_cst (t, &delta, &pfn);
6626 return build_ptrmemfunc_access_expr (t, delta_identifier);
6629 /* Convert value RHS to type TYPE as preparation for an assignment to
6630 an lvalue of type TYPE. ERRTYPE is a string to use in error
6631 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6632 are doing the conversion in order to pass the PARMNUMth argument of
6636 convert_for_assignment (tree type, tree rhs,
6637 const char *errtype, tree fndecl, int parmnum,
6638 tsubst_flags_t complain, int flags)
6641 enum tree_code coder;
6643 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6644 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6645 rhs = TREE_OPERAND (rhs, 0);
6647 rhstype = TREE_TYPE (rhs);
6648 coder = TREE_CODE (rhstype);
6650 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6651 && vector_types_convertible_p (type, rhstype, true))
6652 return convert (type, rhs);
6654 if (rhs == error_mark_node || rhstype == error_mark_node)
6655 return error_mark_node;
6656 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6657 return error_mark_node;
6659 /* The RHS of an assignment cannot have void type. */
6660 if (coder == VOID_TYPE)
6662 if (complain & tf_error)
6663 error ("void value not ignored as it ought to be");
6664 return error_mark_node;
6667 /* Simplify the RHS if possible. */
6668 if (TREE_CODE (rhs) == CONST_DECL)
6669 rhs = DECL_INITIAL (rhs);
6671 if (c_dialect_objc ())
6674 tree rname = fndecl;
6676 if (!strcmp (errtype, "assignment"))
6678 else if (!strcmp (errtype, "initialization"))
6682 tree selector = objc_message_selector ();
6686 if (selector && parmno > 1)
6693 if (objc_compare_types (type, rhstype, parmno, rname))
6694 return convert (type, rhs);
6699 The expression is implicitly converted (clause _conv_) to the
6700 cv-unqualified type of the left operand.
6702 We allow bad conversions here because by the time we get to this point
6703 we are committed to doing the conversion. If we end up doing a bad
6704 conversion, convert_like will complain. */
6705 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
6707 /* When -Wno-pmf-conversions is use, we just silently allow
6708 conversions from pointers-to-members to plain pointers. If
6709 the conversion doesn't work, cp_convert will complain. */
6711 && TYPE_PTR_P (type)
6712 && TYPE_PTRMEMFUNC_P (rhstype))
6713 rhs = cp_convert (strip_top_quals (type), rhs);
6716 if (complain & tf_error)
6718 /* If the right-hand side has unknown type, then it is an
6719 overloaded function. Call instantiate_type to get error
6721 if (rhstype == unknown_type_node)
6722 instantiate_type (type, rhs, tf_warning_or_error);
6724 error ("cannot convert %qT to %qT for argument %qP to %qD",
6725 rhstype, type, parmnum, fndecl);
6727 error ("cannot convert %qT to %qT in %s", rhstype, type,
6730 return error_mark_node;
6733 if (warn_missing_format_attribute)
6735 const enum tree_code codel = TREE_CODE (type);
6736 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6738 && check_missing_format_attribute (type, rhstype)
6739 && (complain & tf_warning))
6740 warning (OPT_Wmissing_format_attribute,
6741 "%s might be a candidate for a format attribute",
6745 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6747 if (warn_parentheses
6748 && type == boolean_type_node
6749 && TREE_CODE (rhs) == MODIFY_EXPR
6750 && !TREE_NO_WARNING (rhs)
6751 && TREE_TYPE (rhs) != boolean_type_node
6752 && (complain & tf_warning))
6754 warning (OPT_Wparentheses,
6755 "suggest parentheses around assignment used as truth value");
6756 TREE_NO_WARNING (rhs) = 1;
6759 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
6763 /* Convert RHS to be of type TYPE.
6764 If EXP is nonzero, it is the target of the initialization.
6765 ERRTYPE is a string to use in error messages.
6767 Two major differences between the behavior of
6768 `convert_for_assignment' and `convert_for_initialization'
6769 are that references are bashed in the former, while
6770 copied in the latter, and aggregates are assigned in
6771 the former (operator=) while initialized in the
6774 If using constructor make sure no conversion operator exists, if one does
6775 exist, an ambiguity exists.
6777 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6780 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6781 const char *errtype, tree fndecl, int parmnum,
6782 tsubst_flags_t complain)
6784 enum tree_code codel = TREE_CODE (type);
6786 enum tree_code coder;
6788 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6789 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6790 if (TREE_CODE (rhs) == NOP_EXPR
6791 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6792 && codel != REFERENCE_TYPE)
6793 rhs = TREE_OPERAND (rhs, 0);
6795 if (type == error_mark_node
6796 || rhs == error_mark_node
6797 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6798 return error_mark_node;
6800 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6801 && TREE_CODE (type) != ARRAY_TYPE
6802 && (TREE_CODE (type) != REFERENCE_TYPE
6803 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6804 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6805 && (TREE_CODE (type) != REFERENCE_TYPE
6806 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6807 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6808 rhs = decay_conversion (rhs);
6810 rhstype = TREE_TYPE (rhs);
6811 coder = TREE_CODE (rhstype);
6813 if (coder == ERROR_MARK)
6814 return error_mark_node;
6816 /* We accept references to incomplete types, so we can
6817 return here before checking if RHS is of complete type. */
6819 if (codel == REFERENCE_TYPE)
6821 /* This should eventually happen in convert_arguments. */
6822 int savew = 0, savee = 0;
6825 savew = warningcount, savee = errorcount;
6826 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6830 if (warningcount > savew)
6831 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6832 else if (errorcount > savee)
6833 error ("in passing argument %P of %q+D", parmnum, fndecl);
6839 exp = require_complete_type (exp);
6840 if (exp == error_mark_node)
6841 return error_mark_node;
6843 rhstype = non_reference (rhstype);
6845 type = complete_type (type);
6847 if (MAYBE_CLASS_TYPE_P (type))
6848 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6850 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6854 /* If RETVAL is the address of, or a reference to, a local variable or
6855 temporary give an appropriate warning. */
6858 maybe_warn_about_returning_address_of_local (tree retval)
6860 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6861 tree whats_returned = retval;
6865 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6866 whats_returned = TREE_OPERAND (whats_returned, 1);
6867 else if (CONVERT_EXPR_P (whats_returned)
6868 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6869 whats_returned = TREE_OPERAND (whats_returned, 0);
6874 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6876 whats_returned = TREE_OPERAND (whats_returned, 0);
6878 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6880 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6881 || TREE_CODE (whats_returned) == TARGET_EXPR)
6883 warning (0, "returning reference to temporary");
6886 if (TREE_CODE (whats_returned) == VAR_DECL
6887 && DECL_NAME (whats_returned)
6888 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6890 warning (0, "reference to non-lvalue returned");
6895 while (TREE_CODE (whats_returned) == COMPONENT_REF
6896 || TREE_CODE (whats_returned) == ARRAY_REF)
6897 whats_returned = TREE_OPERAND (whats_returned, 0);
6899 if (DECL_P (whats_returned)
6900 && DECL_NAME (whats_returned)
6901 && DECL_FUNCTION_SCOPE_P (whats_returned)
6902 && !(TREE_STATIC (whats_returned)
6903 || TREE_PUBLIC (whats_returned)))
6905 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6906 warning (0, "reference to local variable %q+D returned",
6909 warning (0, "address of local variable %q+D returned",
6915 /* Check that returning RETVAL from the current function is valid.
6916 Return an expression explicitly showing all conversions required to
6917 change RETVAL into the function return type, and to assign it to
6918 the DECL_RESULT for the function. Set *NO_WARNING to true if
6919 code reaches end of non-void function warning shouldn't be issued
6920 on this RETURN_EXPR. */
6923 check_return_expr (tree retval, bool *no_warning)
6926 /* The type actually returned by the function, after any
6929 int fn_returns_value_p;
6930 bool named_return_value_okay_p;
6932 *no_warning = false;
6934 /* A `volatile' function is one that isn't supposed to return, ever.
6935 (This is a G++ extension, used to get better code for functions
6936 that call the `volatile' function.) */
6937 if (TREE_THIS_VOLATILE (current_function_decl))
6938 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6940 /* Check for various simple errors. */
6941 if (DECL_DESTRUCTOR_P (current_function_decl))
6944 error ("returning a value from a destructor");
6947 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6949 if (in_function_try_handler)
6950 /* If a return statement appears in a handler of the
6951 function-try-block of a constructor, the program is ill-formed. */
6952 error ("cannot return from a handler of a function-try-block of a constructor");
6954 /* You can't return a value from a constructor. */
6955 error ("returning a value from a constructor");
6959 if (processing_template_decl)
6961 current_function_returns_value = 1;
6962 if (check_for_bare_parameter_packs (retval))
6963 retval = error_mark_node;
6967 /* When no explicit return-value is given in a function with a named
6968 return value, the named return value is used. */
6969 result = DECL_RESULT (current_function_decl);
6970 valtype = TREE_TYPE (result);
6971 gcc_assert (valtype != NULL_TREE);
6972 fn_returns_value_p = !VOID_TYPE_P (valtype);
6973 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6976 /* Check for a return statement with no return value in a function
6977 that's supposed to return a value. */
6978 if (!retval && fn_returns_value_p)
6980 permerror (input_location, "return-statement with no value, in function returning %qT",
6982 /* Clear this, so finish_function won't say that we reach the
6983 end of a non-void function (which we don't, we gave a
6985 current_function_returns_null = 0;
6986 /* And signal caller that TREE_NO_WARNING should be set on the
6987 RETURN_EXPR to avoid control reaches end of non-void function
6988 warnings in tree-cfg.c. */
6991 /* Check for a return statement with a value in a function that
6992 isn't supposed to return a value. */
6993 else if (retval && !fn_returns_value_p)
6995 if (VOID_TYPE_P (TREE_TYPE (retval)))
6996 /* You can return a `void' value from a function of `void'
6997 type. In that case, we have to evaluate the expression for
6998 its side-effects. */
6999 finish_expr_stmt (retval);
7001 permerror (input_location, "return-statement with a value, in function "
7002 "returning 'void'");
7003 current_function_returns_null = 1;
7005 /* There's really no value to return, after all. */
7009 /* Remember that this function can sometimes return without a
7011 current_function_returns_null = 1;
7013 /* Remember that this function did return a value. */
7014 current_function_returns_value = 1;
7016 /* Check for erroneous operands -- but after giving ourselves a
7017 chance to provide an error about returning a value from a void
7019 if (error_operand_p (retval))
7021 current_function_return_value = error_mark_node;
7022 return error_mark_node;
7025 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7026 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7027 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7028 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7030 && retval && null_ptr_cst_p (retval))
7031 warning (0, "%<operator new%> must not return NULL unless it is "
7032 "declared %<throw()%> (or -fcheck-new is in effect)");
7034 /* Effective C++ rule 15. See also start_function. */
7036 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7040 /* The function return type must be a reference to the current
7042 if (TREE_CODE (valtype) == REFERENCE_TYPE
7043 && same_type_ignoring_top_level_qualifiers_p
7044 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7046 /* Returning '*this' is obviously OK. */
7047 if (retval == current_class_ref)
7049 /* If we are calling a function whose return type is the same of
7050 the current class reference, it is ok. */
7051 else if (TREE_CODE (retval) == INDIRECT_REF
7052 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7057 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7060 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7062 [...] For a function with a class return type, if the expression
7063 in the return statement is the name of a local object, and the cv-
7064 unqualified type of the local object is the same as the function
7065 return type, an implementation is permitted to omit creating the tem-
7066 porary object to hold the function return value [...]
7068 So, if this is a value-returning function that always returns the same
7069 local variable, remember it.
7071 It might be nice to be more flexible, and choose the first suitable
7072 variable even if the function sometimes returns something else, but
7073 then we run the risk of clobbering the variable we chose if the other
7074 returned expression uses the chosen variable somehow. And people expect
7075 this restriction, anyway. (jason 2000-11-19)
7077 See finish_function and finalize_nrv for the rest of this optimization. */
7079 named_return_value_okay_p =
7080 (retval != NULL_TREE
7081 /* Must be a local, automatic variable. */
7082 && TREE_CODE (retval) == VAR_DECL
7083 && DECL_CONTEXT (retval) == current_function_decl
7084 && ! TREE_STATIC (retval)
7085 && ! DECL_ANON_UNION_VAR_P (retval)
7086 && (DECL_ALIGN (retval)
7087 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7088 /* The cv-unqualified type of the returned value must be the
7089 same as the cv-unqualified return type of the
7091 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7093 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7094 /* And the returned value must be non-volatile. */
7095 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7097 if (fn_returns_value_p && flag_elide_constructors)
7099 if (named_return_value_okay_p
7100 && (current_function_return_value == NULL_TREE
7101 || current_function_return_value == retval))
7102 current_function_return_value = retval;
7104 current_function_return_value = error_mark_node;
7107 /* We don't need to do any conversions when there's nothing being
7112 /* Do any required conversions. */
7113 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7114 /* No conversions are required. */
7118 /* The type the function is declared to return. */
7119 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7120 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7122 /* The functype's return type will have been set to void, if it
7123 was an incomplete type. Just treat this as 'return;' */
7124 if (VOID_TYPE_P (functype))
7125 return error_mark_node;
7127 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7128 treated as an rvalue for the purposes of overload resolution to
7129 favor move constructors over copy constructors. */
7130 if ((cxx_dialect != cxx98)
7131 && named_return_value_okay_p
7132 /* The variable must not have the `volatile' qualifier. */
7133 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7134 /* The return type must be a class type. */
7135 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7136 flags = flags | LOOKUP_PREFER_RVALUE;
7138 /* First convert the value to the function's return type, then
7139 to the type of return value's location to handle the
7140 case that functype is smaller than the valtype. */
7141 retval = convert_for_initialization
7142 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7143 tf_warning_or_error);
7144 retval = convert (valtype, retval);
7146 /* If the conversion failed, treat this just like `return;'. */
7147 if (retval == error_mark_node)
7149 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7150 else if (! cfun->returns_struct
7151 && TREE_CODE (retval) == TARGET_EXPR
7152 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7153 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7154 TREE_OPERAND (retval, 0));
7156 maybe_warn_about_returning_address_of_local (retval);
7159 /* Actually copy the value returned into the appropriate location. */
7160 if (retval && retval != result)
7161 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7167 /* Returns nonzero if the pointer-type FROM can be converted to the
7168 pointer-type TO via a qualification conversion. If CONSTP is -1,
7169 then we return nonzero if the pointers are similar, and the
7170 cv-qualification signature of FROM is a proper subset of that of TO.
7172 If CONSTP is positive, then all outer pointers have been
7176 comp_ptr_ttypes_real (tree to, tree from, int constp)
7178 bool to_more_cv_qualified = false;
7179 bool is_opaque_pointer = false;
7181 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7183 if (TREE_CODE (to) != TREE_CODE (from))
7186 if (TREE_CODE (from) == OFFSET_TYPE
7187 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7188 TYPE_OFFSET_BASETYPE (to)))
7191 /* Const and volatile mean something different for function types,
7192 so the usual checks are not appropriate. */
7193 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7195 /* In Objective-C++, some types may have been 'volatilized' by
7196 the compiler for EH; when comparing them here, the volatile
7197 qualification must be ignored. */
7198 bool objc_quals_match = objc_type_quals_match (to, from);
7200 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7203 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7207 to_more_cv_qualified = true;
7211 constp &= TYPE_READONLY (to);
7214 if (TREE_CODE (to) == VECTOR_TYPE)
7215 is_opaque_pointer = vector_targets_convertible_p (to, from);
7217 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7218 return ((constp >= 0 || to_more_cv_qualified)
7219 && (is_opaque_pointer
7220 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7224 /* When comparing, say, char ** to char const **, this function takes
7225 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7226 types to this function. */
7229 comp_ptr_ttypes (tree to, tree from)
7231 return comp_ptr_ttypes_real (to, from, 1);
7234 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7235 type or inheritance-related types, regardless of cv-quals. */
7238 ptr_reasonably_similar (const_tree to, const_tree from)
7240 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7242 /* Any target type is similar enough to void. */
7243 if (TREE_CODE (to) == VOID_TYPE
7244 || TREE_CODE (from) == VOID_TYPE)
7247 if (TREE_CODE (to) != TREE_CODE (from))
7250 if (TREE_CODE (from) == OFFSET_TYPE
7251 && comptypes (TYPE_OFFSET_BASETYPE (to),
7252 TYPE_OFFSET_BASETYPE (from),
7253 COMPARE_BASE | COMPARE_DERIVED))
7256 if (TREE_CODE (to) == VECTOR_TYPE
7257 && vector_types_convertible_p (to, from, false))
7260 if (TREE_CODE (to) == INTEGER_TYPE
7261 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7264 if (TREE_CODE (to) == FUNCTION_TYPE)
7267 if (TREE_CODE (to) != POINTER_TYPE)
7269 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7270 COMPARE_BASE | COMPARE_DERIVED);
7274 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7275 pointer-to-member types) are the same, ignoring cv-qualification at
7279 comp_ptr_ttypes_const (tree to, tree from)
7281 bool is_opaque_pointer = false;
7283 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7285 if (TREE_CODE (to) != TREE_CODE (from))
7288 if (TREE_CODE (from) == OFFSET_TYPE
7289 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7290 TYPE_OFFSET_BASETYPE (to)))
7293 if (TREE_CODE (to) == VECTOR_TYPE)
7294 is_opaque_pointer = vector_targets_convertible_p (to, from);
7296 if (TREE_CODE (to) != POINTER_TYPE)
7297 return (is_opaque_pointer
7298 || same_type_ignoring_top_level_qualifiers_p (to, from));
7302 /* Returns the type qualifiers for this type, including the qualifiers on the
7303 elements for an array type. */
7306 cp_type_quals (const_tree type)
7308 /* This CONST_CAST is okay because strip_array_types returns its
7309 argument unmodified and we assign it to a const_tree. */
7310 type = strip_array_types (CONST_CAST_TREE(type));
7311 if (type == error_mark_node)
7312 return TYPE_UNQUALIFIED;
7313 return TYPE_QUALS (type);
7316 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7320 cp_type_readonly (const_tree type)
7322 /* This CONST_CAST is okay because strip_array_types returns its
7323 argument unmodified and we assign it to a const_tree. */
7324 type = strip_array_types (CONST_CAST_TREE(type));
7325 return TYPE_READONLY (type);
7328 /* Returns nonzero if the TYPE contains a mutable member. */
7331 cp_has_mutable_p (const_tree type)
7333 /* This CONST_CAST is okay because strip_array_types returns its
7334 argument unmodified and we assign it to a const_tree. */
7335 type = strip_array_types (CONST_CAST_TREE(type));
7337 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7340 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7341 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7342 approximation. In particular, consider:
7345 struct S { int i; };
7346 const S s = { f(); }
7348 Here, we will make "s" as TREE_READONLY (because it is declared
7349 "const") -- only to reverse ourselves upon seeing that the
7350 initializer is non-constant. */
7353 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7355 tree type = TREE_TYPE (decl);
7357 if (type == error_mark_node)
7360 if (TREE_CODE (decl) == TYPE_DECL)
7363 if (TREE_CODE (type) == FUNCTION_TYPE
7364 && type_quals != TYPE_UNQUALIFIED)
7366 /* This was an error in C++98 (cv-qualifiers cannot be added to
7367 a function type), but DR 295 makes the code well-formed by
7368 dropping the extra qualifiers. */
7371 tree bad_type = build_qualified_type (type, type_quals);
7372 pedwarn (input_location, OPT_pedantic,
7373 "ignoring %qV qualifiers added to function type %qT",
7377 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7381 /* Avoid setting TREE_READONLY incorrectly. */
7382 if (/* If the object has a constructor, the constructor may modify
7384 TYPE_NEEDS_CONSTRUCTING (type)
7385 /* If the type isn't complete, we don't know yet if it will need
7387 || !COMPLETE_TYPE_P (type)
7388 /* If the type has a mutable component, that component might be
7390 || TYPE_HAS_MUTABLE_P (type))
7391 type_quals &= ~TYPE_QUAL_CONST;
7393 c_apply_type_quals_to_decl (type_quals, decl);
7396 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7397 exemplar types such that casting T1 to T2 is casting away constness
7398 if and only if there is no implicit conversion from T1 to T2. */
7401 casts_away_constness_r (tree *t1, tree *t2)
7406 /* [expr.const.cast]
7408 For multi-level pointer to members and multi-level mixed pointers
7409 and pointers to members (conv.qual), the "member" aspect of a
7410 pointer to member level is ignored when determining if a const
7411 cv-qualifier has been cast away. */
7412 /* [expr.const.cast]
7414 For two pointer types:
7416 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7417 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7420 casting from X1 to X2 casts away constness if, for a non-pointer
7421 type T there does not exist an implicit conversion (clause
7424 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7428 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7429 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7430 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7432 *t1 = cp_build_qualified_type (void_type_node,
7433 cp_type_quals (*t1));
7434 *t2 = cp_build_qualified_type (void_type_node,
7435 cp_type_quals (*t2));
7439 quals1 = cp_type_quals (*t1);
7440 quals2 = cp_type_quals (*t2);
7442 if (TYPE_PTRMEM_P (*t1))
7443 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7445 *t1 = TREE_TYPE (*t1);
7446 if (TYPE_PTRMEM_P (*t2))
7447 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7449 *t2 = TREE_TYPE (*t2);
7451 casts_away_constness_r (t1, t2);
7452 *t1 = build_pointer_type (*t1);
7453 *t2 = build_pointer_type (*t2);
7454 *t1 = cp_build_qualified_type (*t1, quals1);
7455 *t2 = cp_build_qualified_type (*t2, quals2);
7458 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7461 ??? This function returns non-zero if casting away qualifiers not
7462 just const. We would like to return to the caller exactly which
7463 qualifiers are casted away to give more accurate diagnostics.
7467 casts_away_constness (tree t1, tree t2)
7469 if (TREE_CODE (t2) == REFERENCE_TYPE)
7471 /* [expr.const.cast]
7473 Casting from an lvalue of type T1 to an lvalue of type T2
7474 using a reference cast casts away constness if a cast from an
7475 rvalue of type "pointer to T1" to the type "pointer to T2"
7476 casts away constness. */
7477 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7478 return casts_away_constness (build_pointer_type (t1),
7479 build_pointer_type (TREE_TYPE (t2)));
7482 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7483 /* [expr.const.cast]
7485 Casting from an rvalue of type "pointer to data member of X
7486 of type T1" to the type "pointer to data member of Y of type
7487 T2" casts away constness if a cast from an rvalue of type
7488 "pointer to T1" to the type "pointer to T2" casts away
7490 return casts_away_constness
7491 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7492 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7494 /* Casting away constness is only something that makes sense for
7495 pointer or reference types. */
7496 if (TREE_CODE (t1) != POINTER_TYPE
7497 || TREE_CODE (t2) != POINTER_TYPE)
7500 /* Top-level qualifiers don't matter. */
7501 t1 = TYPE_MAIN_VARIANT (t1);
7502 t2 = TYPE_MAIN_VARIANT (t2);
7503 casts_away_constness_r (&t1, &t2);
7504 if (!can_convert (t2, t1))
7510 /* If T is a REFERENCE_TYPE return the type to which T refers.
7511 Otherwise, return T itself. */
7514 non_reference (tree t)
7516 if (TREE_CODE (t) == REFERENCE_TYPE)
7522 /* Return nonzero if REF is an lvalue valid for this language;
7523 otherwise, print an error message and return zero. USE says
7524 how the lvalue is being used and so selects the error message. */
7527 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
7529 int win = lvalue_p (ref);
7531 if (!win && (complain & tf_error))