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 /* FIXME: Attributes. */
264 gcc_assert (ARITHMETIC_TYPE_P (t1)
265 || TREE_CODE (t1) == VECTOR_TYPE
266 || UNSCOPED_ENUM_P (t1));
267 gcc_assert (ARITHMETIC_TYPE_P (t2)
268 || TREE_CODE (t2) == VECTOR_TYPE
269 || UNSCOPED_ENUM_P (t2));
271 /* In what follows, we slightly generalize the rules given in [expr] so
272 as to deal with `long long' and `complex'. First, merge the
274 attributes = (*targetm.merge_type_attributes) (t1, t2);
276 /* If one type is complex, form the common type of the non-complex
277 components, then make that complex. Use T1 or T2 if it is the
279 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
281 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
282 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
284 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
286 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
287 return build_type_attribute_variant (t1, attributes);
288 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
289 return build_type_attribute_variant (t2, attributes);
291 return build_type_attribute_variant (build_complex_type (subtype),
295 if (code1 == VECTOR_TYPE)
297 /* When we get here we should have two vectors of the same size.
298 Just prefer the unsigned one if present. */
299 if (TYPE_UNSIGNED (t1))
300 return build_type_attribute_variant (t1, attributes);
302 return build_type_attribute_variant (t2, attributes);
305 /* If only one is real, use it as the result. */
306 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
307 return build_type_attribute_variant (t1, attributes);
308 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
309 return build_type_attribute_variant (t2, attributes);
311 /* Both real or both integers; use the one with greater precision. */
312 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
313 return build_type_attribute_variant (t1, attributes);
314 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
315 return build_type_attribute_variant (t2, attributes);
317 /* The types are the same; no need to do anything fancy. */
318 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
319 return build_type_attribute_variant (t1, attributes);
321 if (code1 != REAL_TYPE)
323 /* If one is unsigned long long, then convert the other to unsigned
325 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
326 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
327 return build_type_attribute_variant (long_long_unsigned_type_node,
329 /* If one is a long long, and the other is an unsigned long, and
330 long long can represent all the values of an unsigned long, then
331 convert to a long long. Otherwise, convert to an unsigned long
332 long. Otherwise, if either operand is long long, convert the
335 Since we're here, we know the TYPE_PRECISION is the same;
336 therefore converting to long long cannot represent all the values
337 of an unsigned long, so we choose unsigned long long in that
339 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
340 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
342 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
343 ? long_long_unsigned_type_node
344 : long_long_integer_type_node);
345 return build_type_attribute_variant (t, attributes);
348 /* Go through the same procedure, but for longs. */
349 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
350 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
351 return build_type_attribute_variant (long_unsigned_type_node,
353 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
354 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
356 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
357 ? long_unsigned_type_node : long_integer_type_node);
358 return build_type_attribute_variant (t, attributes);
360 /* Otherwise prefer the unsigned one. */
361 if (TYPE_UNSIGNED (t1))
362 return build_type_attribute_variant (t1, attributes);
364 return build_type_attribute_variant (t2, attributes);
368 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
369 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
370 return build_type_attribute_variant (long_double_type_node,
372 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
373 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
374 return build_type_attribute_variant (double_type_node,
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
378 return build_type_attribute_variant (float_type_node,
381 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
382 the standard C++ floating-point types. Logic earlier in this
383 function has already eliminated the possibility that
384 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
385 compelling reason to choose one or the other. */
386 return build_type_attribute_variant (t1, attributes);
390 /* T1 and T2 are arithmetic or enumeration types. Return the type
391 that will result from the "usual arithmetic conversions" on T1 and
392 T2 as described in [expr]. */
395 type_after_usual_arithmetic_conversions (tree t1, tree t2)
397 gcc_assert (ARITHMETIC_TYPE_P (t1)
398 || TREE_CODE (t1) == VECTOR_TYPE
399 || UNSCOPED_ENUM_P (t1));
400 gcc_assert (ARITHMETIC_TYPE_P (t2)
401 || TREE_CODE (t2) == VECTOR_TYPE
402 || UNSCOPED_ENUM_P (t2));
404 /* Perform the integral promotions. We do not promote real types here. */
405 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
406 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
408 t1 = type_promotes_to (t1);
409 t2 = type_promotes_to (t2);
412 return cp_common_type (t1, t2);
415 /* Subroutine of composite_pointer_type to implement the recursive
416 case. See that function for documentation fo the parameters. */
419 composite_pointer_type_r (tree t1, tree t2, const char* location,
420 tsubst_flags_t complain)
427 /* Determine the types pointed to by T1 and T2. */
428 if (TREE_CODE (t1) == POINTER_TYPE)
430 pointee1 = TREE_TYPE (t1);
431 pointee2 = TREE_TYPE (t2);
435 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
436 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
441 Otherwise, the composite pointer type is a pointer type
442 similar (_conv.qual_) to the type of one of the operands,
443 with a cv-qualification signature (_conv.qual_) that is the
444 union of the cv-qualification signatures of the operand
446 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
447 result_type = pointee1;
448 else if ((TREE_CODE (pointee1) == POINTER_TYPE
449 && TREE_CODE (pointee2) == POINTER_TYPE)
450 || (TYPE_PTR_TO_MEMBER_P (pointee1)
451 && TYPE_PTR_TO_MEMBER_P (pointee2)))
452 result_type = composite_pointer_type_r (pointee1, pointee2, location,
456 if (complain & tf_error)
457 permerror (input_location, "%s between distinct pointer types %qT and %qT "
460 result_type = void_type_node;
462 result_type = cp_build_qualified_type (result_type,
463 (cp_type_quals (pointee1)
464 | cp_type_quals (pointee2)));
465 /* If the original types were pointers to members, so is the
467 if (TYPE_PTR_TO_MEMBER_P (t1))
469 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
470 TYPE_PTRMEM_CLASS_TYPE (t2))
471 && (complain & tf_error))
472 permerror (input_location, "%s between distinct pointer types %qT and %qT "
475 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
479 result_type = build_pointer_type (result_type);
481 /* Merge the attributes. */
482 attributes = (*targetm.merge_type_attributes) (t1, t2);
483 return build_type_attribute_variant (result_type, attributes);
486 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
487 ARG1 and ARG2 are the values with those types. The LOCATION is a
488 string describing the current location, in case an error occurs.
490 This routine also implements the computation of a common type for
491 pointers-to-members as per [expr.eq]. */
494 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
495 const char* location, tsubst_flags_t complain)
502 If one operand is a null pointer constant, the composite pointer
503 type is the type of the other operand. */
504 if (null_ptr_cst_p (arg1))
506 if (null_ptr_cst_p (arg2))
513 If one of the operands has type "pointer to cv1 void*", then
514 the other has type "pointer to cv2T", and the composite pointer
515 type is "pointer to cv12 void", where cv12 is the union of cv1
518 If either type is a pointer to void, make sure it is T1. */
519 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
527 /* Now, if T1 is a pointer to void, merge the qualifiers. */
528 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
533 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
534 pedwarn (input_location, OPT_pedantic, "ISO C++ forbids %s "
535 "between pointer of type %<void *%> and pointer-to-function",
538 = cp_build_qualified_type (void_type_node,
539 (cp_type_quals (TREE_TYPE (t1))
540 | cp_type_quals (TREE_TYPE (t2))));
541 result_type = build_pointer_type (result_type);
542 /* Merge the attributes. */
543 attributes = (*targetm.merge_type_attributes) (t1, t2);
544 return build_type_attribute_variant (result_type, attributes);
547 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
548 && TREE_CODE (t2) == POINTER_TYPE)
550 if (objc_compare_types (t1, t2, -3, NULL_TREE))
554 /* [expr.eq] permits the application of a pointer conversion to
555 bring the pointers to a common type. */
556 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
557 && CLASS_TYPE_P (TREE_TYPE (t1))
558 && CLASS_TYPE_P (TREE_TYPE (t2))
559 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
562 class1 = TREE_TYPE (t1);
563 class2 = TREE_TYPE (t2);
565 if (DERIVED_FROM_P (class1, class2))
566 t2 = (build_pointer_type
567 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
568 else if (DERIVED_FROM_P (class2, class1))
569 t1 = (build_pointer_type
570 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
573 if (complain & tf_error)
574 error ("%s between distinct pointer types %qT and %qT "
575 "lacks a cast", location, t1, t2);
576 return error_mark_node;
579 /* [expr.eq] permits the application of a pointer-to-member
580 conversion to change the class type of one of the types. */
581 else if (TYPE_PTR_TO_MEMBER_P (t1)
582 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
583 TYPE_PTRMEM_CLASS_TYPE (t2)))
585 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
586 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
588 if (DERIVED_FROM_P (class1, class2))
589 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
590 else if (DERIVED_FROM_P (class2, class1))
591 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
594 if (complain & tf_error)
595 error ("%s between distinct pointer-to-member types %qT and %qT "
596 "lacks a cast", location, t1, t2);
597 return error_mark_node;
601 return composite_pointer_type_r (t1, t2, location, complain);
604 /* Return the merged type of two types.
605 We assume that comptypes has already been done and returned 1;
606 if that isn't so, this may crash.
608 This just combines attributes and default arguments; any other
609 differences would cause the two types to compare unalike. */
612 merge_types (tree t1, tree t2)
614 enum tree_code code1;
615 enum tree_code code2;
618 /* Save time if the two types are the same. */
621 if (original_type (t1) == original_type (t2))
624 /* If one type is nonsense, use the other. */
625 if (t1 == error_mark_node)
627 if (t2 == error_mark_node)
630 /* Merge the attributes. */
631 attributes = (*targetm.merge_type_attributes) (t1, t2);
633 if (TYPE_PTRMEMFUNC_P (t1))
634 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
635 if (TYPE_PTRMEMFUNC_P (t2))
636 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
638 code1 = TREE_CODE (t1);
639 code2 = TREE_CODE (t2);
642 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
643 if (code1 == TYPENAME_TYPE)
645 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
646 code1 = TREE_CODE (t1);
650 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
651 code2 = TREE_CODE (t2);
659 /* For two pointers, do this recursively on the target type. */
661 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
662 int quals = cp_type_quals (t1);
664 if (code1 == POINTER_TYPE)
665 t1 = build_pointer_type (target);
667 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
668 t1 = build_type_attribute_variant (t1, attributes);
669 t1 = cp_build_qualified_type (t1, quals);
671 if (TREE_CODE (target) == METHOD_TYPE)
672 t1 = build_ptrmemfunc_type (t1);
681 quals = cp_type_quals (t1);
682 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
683 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
684 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
686 t1 = cp_build_qualified_type (t1, quals);
692 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
693 /* Save space: see if the result is identical to one of the args. */
694 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
695 return build_type_attribute_variant (t1, attributes);
696 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
697 return build_type_attribute_variant (t2, attributes);
698 /* Merge the element types, and have a size if either arg has one. */
699 t1 = build_cplus_array_type
700 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
705 /* Function types: prefer the one that specified arg types.
706 If both do, merge the arg types. Also merge the return types. */
708 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
709 tree p1 = TYPE_ARG_TYPES (t1);
710 tree p2 = TYPE_ARG_TYPES (t2);
713 /* Save space: see if the result is identical to one of the args. */
714 if (valtype == TREE_TYPE (t1) && ! p2)
715 return cp_build_type_attribute_variant (t1, attributes);
716 if (valtype == TREE_TYPE (t2) && ! p1)
717 return cp_build_type_attribute_variant (t2, attributes);
719 /* Simple way if one arg fails to specify argument types. */
720 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
722 rval = build_function_type (valtype, p2);
723 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
724 rval = build_exception_variant (rval, raises);
725 return cp_build_type_attribute_variant (rval, attributes);
727 raises = TYPE_RAISES_EXCEPTIONS (t1);
728 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
730 rval = build_function_type (valtype, p1);
732 rval = build_exception_variant (rval, raises);
733 return cp_build_type_attribute_variant (rval, attributes);
736 rval = build_function_type (valtype, commonparms (p1, p2));
737 t1 = build_exception_variant (rval, raises);
743 /* Get this value the long way, since TYPE_METHOD_BASETYPE
744 is just the main variant of this. */
745 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
746 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
749 /* If this was a member function type, get back to the
750 original type of type member function (i.e., without
751 the class instance variable up front. */
752 t1 = build_function_type (TREE_TYPE (t1),
753 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
754 t2 = build_function_type (TREE_TYPE (t2),
755 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
756 t3 = merge_types (t1, t2);
757 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
758 TYPE_ARG_TYPES (t3));
759 t1 = build_exception_variant (t3, raises);
764 /* There is no need to merge attributes into a TYPENAME_TYPE.
765 When the type is instantiated it will have whatever
766 attributes result from the instantiation. */
772 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
774 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
777 return cp_build_type_attribute_variant (t1, attributes);
780 /* Wrapper around cp_common_type that is used by c-common.c and other
781 front end optimizations that remove promotions.
783 Return the common type for two arithmetic types T1 and T2 under the
784 usual arithmetic conversions. The default conversions have already
785 been applied, and enumerated types converted to their compatible
789 common_type (tree t1, tree t2)
791 /* If one type is nonsense, use the other */
792 if (t1 == error_mark_node)
794 if (t2 == error_mark_node)
797 return cp_common_type (t1, t2);
800 /* Return the common type of two pointer types T1 and T2. This is the
801 type for the result of most arithmetic operations if the operands
802 have the given two types.
804 We assume that comp_target_types has already been done and returned
805 nonzero; if that isn't so, this may crash. */
808 common_pointer_type (tree t1, tree t2)
810 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
811 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
812 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
814 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
815 "conversion", tf_warning_or_error);
818 /* Compare two exception specifier types for exactness or subsetness, if
819 allowed. Returns false for mismatch, true for match (same, or
822 [except.spec] "If a class X ... objects of class X or any class publicly
823 and unambiguously derived from X. Similarly, if a pointer type Y * ...
824 exceptions of type Y * or that are pointers to any type publicly and
825 unambiguously derived from Y. Otherwise a function only allows exceptions
826 that have the same type ..."
827 This does not mention cv qualifiers and is different to what throw
828 [except.throw] and catch [except.catch] will do. They will ignore the
829 top level cv qualifiers, and allow qualifiers in the pointer to class
832 We implement the letter of the standard. */
835 comp_except_types (tree a, tree b, bool exact)
837 if (same_type_p (a, b))
841 if (cp_type_quals (a) || cp_type_quals (b))
844 if (TREE_CODE (a) == POINTER_TYPE
845 && TREE_CODE (b) == POINTER_TYPE)
849 if (cp_type_quals (a) || cp_type_quals (b))
853 if (TREE_CODE (a) != RECORD_TYPE
854 || TREE_CODE (b) != RECORD_TYPE)
857 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
863 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
864 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
865 otherwise it must be exact. Exception lists are unordered, but
866 we've already filtered out duplicates. Most lists will be in order,
867 we should try to make use of that. */
870 comp_except_specs (const_tree t1, const_tree t2, bool exact)
879 if (t1 == NULL_TREE) /* T1 is ... */
880 return t2 == NULL_TREE || !exact;
881 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
882 return t2 != NULL_TREE && !TREE_VALUE (t2);
883 if (t2 == NULL_TREE) /* T2 is ... */
885 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
888 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
889 Count how many we find, to determine exactness. For exact matching and
890 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
892 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
894 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
896 tree a = TREE_VALUE (probe);
897 tree b = TREE_VALUE (t2);
899 if (comp_except_types (a, b, exact))
901 if (probe == base && exact)
902 base = TREE_CHAIN (probe);
907 if (probe == NULL_TREE)
910 return !exact || base == NULL_TREE || length == list_length (t1);
913 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
914 [] can match [size]. */
917 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
926 /* The type of the array elements must be the same. */
927 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
930 d1 = TYPE_DOMAIN (t1);
931 d2 = TYPE_DOMAIN (t2);
936 /* If one of the arrays is dimensionless, and the other has a
937 dimension, they are of different types. However, it is valid to
945 declarations for an array object can specify
946 array types that differ by the presence or absence of a major
947 array bound (_dcl.array_). */
949 return allow_redeclaration;
951 /* Check that the dimensions are the same. */
953 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
955 max1 = TYPE_MAX_VALUE (d1);
956 max2 = TYPE_MAX_VALUE (d2);
957 if (processing_template_decl && !abi_version_at_least (2)
958 && !value_dependent_expression_p (max1)
959 && !value_dependent_expression_p (max2))
961 /* With abi-1 we do not fold non-dependent array bounds, (and
962 consequently mangle them incorrectly). We must therefore
963 fold them here, to verify the domains have the same
969 if (!cp_tree_equal (max1, max2))
975 /* Subroutine in comptypes. */
978 structural_comptypes (tree t1, tree t2, int strict)
983 /* Suppress errors caused by previously reported errors. */
984 if (t1 == error_mark_node || t2 == error_mark_node)
987 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
989 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
990 current instantiation. */
991 if (TREE_CODE (t1) == TYPENAME_TYPE)
992 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
994 if (TREE_CODE (t2) == TYPENAME_TYPE)
995 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
997 if (TYPE_PTRMEMFUNC_P (t1))
998 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
999 if (TYPE_PTRMEMFUNC_P (t2))
1000 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1002 /* Different classes of types can't be compatible. */
1003 if (TREE_CODE (t1) != TREE_CODE (t2))
1006 /* Qualifiers must match. For array types, we will check when we
1007 recur on the array element types. */
1008 if (TREE_CODE (t1) != ARRAY_TYPE
1009 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
1011 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1014 /* Allow for two different type nodes which have essentially the same
1015 definition. Note that we already checked for equality of the type
1016 qualifiers (just above). */
1018 if (TREE_CODE (t1) != ARRAY_TYPE
1019 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1022 /* Compare the types. Break out if they could be the same. */
1023 switch (TREE_CODE (t1))
1027 /* All void and bool types are the same. */
1031 case FIXED_POINT_TYPE:
1033 /* With these nodes, we can't determine type equivalence by
1034 looking at what is stored in the nodes themselves, because
1035 two nodes might have different TYPE_MAIN_VARIANTs but still
1036 represent the same type. For example, wchar_t and int could
1037 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1038 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1039 and are distinct types. On the other hand, int and the
1042 typedef int INT __attribute((may_alias));
1044 have identical properties, different TYPE_MAIN_VARIANTs, but
1045 represent the same type. The canonical type system keeps
1046 track of equivalence in this case, so we fall back on it. */
1047 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1049 case TEMPLATE_TEMPLATE_PARM:
1050 case BOUND_TEMPLATE_TEMPLATE_PARM:
1051 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1052 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1053 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1054 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1056 if (!comp_template_parms
1057 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1058 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1060 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1062 /* Don't check inheritance. */
1063 strict = COMPARE_STRICT;
1068 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1069 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1070 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1071 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1074 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1076 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1082 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1083 strict & ~COMPARE_REDECLARATION))
1085 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1089 case REFERENCE_TYPE:
1090 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1092 /* fall through to checks for pointer types */
1095 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1096 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1097 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1103 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1105 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1110 /* Target types must match incl. qualifiers. */
1111 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1115 case TEMPLATE_TYPE_PARM:
1116 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1117 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1118 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1119 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1124 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1125 TYPENAME_TYPE_FULLNAME (t2)))
1127 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1131 case UNBOUND_CLASS_TEMPLATE:
1132 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1134 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1139 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1144 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1145 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1149 case TYPE_PACK_EXPANSION:
1150 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1151 PACK_EXPANSION_PATTERN (t2));
1154 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1155 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1156 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1157 DECLTYPE_TYPE_EXPR (t2)))
1165 /* If we get here, we know that from a target independent POV the
1166 types are the same. Make sure the target attributes are also
1168 return targetm.comp_type_attributes (t1, t2);
1171 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1172 is a bitwise-or of the COMPARE_* flags. */
1175 comptypes (tree t1, tree t2, int strict)
1177 if (strict == COMPARE_STRICT)
1182 if (t1 == error_mark_node || t2 == error_mark_node)
1185 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1186 /* At least one of the types requires structural equality, so
1187 perform a deep check. */
1188 return structural_comptypes (t1, t2, strict);
1190 #ifdef ENABLE_CHECKING
1191 if (USE_CANONICAL_TYPES)
1193 bool result = structural_comptypes (t1, t2, strict);
1195 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1196 /* The two types are structurally equivalent, but their
1197 canonical types were different. This is a failure of the
1198 canonical type propagation code.*/
1200 ("canonical types differ for identical types %T and %T",
1202 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1203 /* Two types are structurally different, but the canonical
1204 types are the same. This means we were over-eager in
1205 assigning canonical types. */
1207 ("same canonical type node for different types %T and %T",
1213 if (USE_CANONICAL_TYPES)
1214 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1217 return structural_comptypes (t1, t2, strict);
1219 else if (strict == COMPARE_STRUCTURAL)
1220 return structural_comptypes (t1, t2, COMPARE_STRICT);
1222 return structural_comptypes (t1, t2, strict);
1225 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1228 at_least_as_qualified_p (const_tree type1, const_tree type2)
1230 int q1 = cp_type_quals (type1);
1231 int q2 = cp_type_quals (type2);
1233 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1234 return (q1 & q2) == q2;
1237 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1238 more cv-qualified that TYPE1, and 0 otherwise. */
1241 comp_cv_qualification (const_tree type1, const_tree type2)
1243 int q1 = cp_type_quals (type1);
1244 int q2 = cp_type_quals (type2);
1249 if ((q1 & q2) == q2)
1251 else if ((q1 & q2) == q1)
1257 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1258 subset of the cv-qualification signature of TYPE2, and the types
1259 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1262 comp_cv_qual_signature (tree type1, tree type2)
1264 if (comp_ptr_ttypes_real (type2, type1, -1))
1266 else if (comp_ptr_ttypes_real (type1, type2, -1))
1272 /* Subroutines of `comptypes'. */
1274 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1275 equivalent in the sense that functions with those parameter types
1276 can have equivalent types. The two lists must be equivalent,
1277 element by element. */
1280 compparms (const_tree parms1, const_tree parms2)
1284 /* An unspecified parmlist matches any specified parmlist
1285 whose argument types don't need default promotions. */
1287 for (t1 = parms1, t2 = parms2;
1289 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1291 /* If one parmlist is shorter than the other,
1292 they fail to match. */
1295 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1302 /* Process a sizeof or alignof expression where the operand is a
1306 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1311 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1312 if (type == error_mark_node)
1313 return error_mark_node;
1315 type = non_reference (type);
1316 if (TREE_CODE (type) == METHOD_TYPE)
1319 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1320 "invalid application of %qs to a member function",
1321 operator_name_info[(int) op].name);
1322 value = size_one_node;
1325 dependent_p = dependent_type_p (type);
1327 complete_type (type);
1329 /* VLA types will have a non-constant size. In the body of an
1330 uninstantiated template, we don't need to try to compute the
1331 value, because the sizeof expression is not an integral
1332 constant expression in that case. And, if we do try to
1333 compute the value, we'll likely end up with SAVE_EXPRs, which
1334 the template substitution machinery does not expect to see. */
1335 || (processing_template_decl
1336 && COMPLETE_TYPE_P (type)
1337 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1339 value = build_min (op, size_type_node, type);
1340 TREE_READONLY (value) = 1;
1344 return c_sizeof_or_alignof_type (complete_type (type),
1349 /* Return the size of the type, without producing any warnings for
1350 types whose size cannot be taken. This routine should be used only
1351 in some other routine that has already produced a diagnostic about
1352 using the size of such a type. */
1354 cxx_sizeof_nowarn (tree type)
1356 if (TREE_CODE (type) == FUNCTION_TYPE
1357 || TREE_CODE (type) == VOID_TYPE
1358 || TREE_CODE (type) == ERROR_MARK)
1359 return size_one_node;
1360 else if (!COMPLETE_TYPE_P (type))
1361 return size_zero_node;
1363 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1366 /* Process a sizeof expression where the operand is an expression. */
1369 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1371 if (e == error_mark_node)
1372 return error_mark_node;
1374 if (processing_template_decl)
1376 e = build_min (SIZEOF_EXPR, size_type_node, e);
1377 TREE_SIDE_EFFECTS (e) = 0;
1378 TREE_READONLY (e) = 1;
1383 if (TREE_CODE (e) == COMPONENT_REF
1384 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1385 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1387 if (complain & tf_error)
1388 error ("invalid application of %<sizeof%> to a bit-field");
1390 return error_mark_node;
1393 else if (is_overloaded_fn (e))
1395 if (complain & tf_error)
1396 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1399 return error_mark_node;
1402 else if (type_unknown_p (e))
1404 if (complain & tf_error)
1405 cxx_incomplete_type_error (e, TREE_TYPE (e));
1407 return error_mark_node;
1413 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1416 /* Implement the __alignof keyword: Return the minimum required
1417 alignment of E, measured in bytes. For VAR_DECL's and
1418 FIELD_DECL's return DECL_ALIGN (which can be set from an
1419 "aligned" __attribute__ specification). */
1422 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1426 if (e == error_mark_node)
1427 return error_mark_node;
1429 if (processing_template_decl)
1431 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1432 TREE_SIDE_EFFECTS (e) = 0;
1433 TREE_READONLY (e) = 1;
1438 if (TREE_CODE (e) == VAR_DECL)
1439 t = size_int (DECL_ALIGN_UNIT (e));
1440 else if (TREE_CODE (e) == COMPONENT_REF
1441 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1442 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1444 if (complain & tf_error)
1445 error ("invalid application of %<__alignof%> to a bit-field");
1447 return error_mark_node;
1450 else if (TREE_CODE (e) == COMPONENT_REF
1451 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1452 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1453 else if (is_overloaded_fn (e))
1455 if (complain & tf_error)
1456 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1459 return error_mark_node;
1460 if (TREE_CODE (e) == FUNCTION_DECL)
1461 t = size_int (DECL_ALIGN_UNIT (e));
1465 else if (type_unknown_p (e))
1467 if (complain & tf_error)
1468 cxx_incomplete_type_error (e, TREE_TYPE (e));
1470 return error_mark_node;
1474 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1475 complain & tf_error);
1477 return fold_convert (size_type_node, t);
1480 /* Process a sizeof or alignof expression E with code OP where the operand
1481 is an expression. */
1484 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1486 if (op == SIZEOF_EXPR)
1487 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1489 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1492 /* EXPR is being used in a context that is not a function call.
1497 The expression can be used only as the left-hand operand of a
1498 member function call.
1500 [expr.mptr.operator]
1502 If the result of .* or ->* is a function, then that result can be
1503 used only as the operand for the function call operator ().
1505 by issuing an error message if appropriate. Returns true iff EXPR
1506 violates these rules. */
1509 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1511 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1513 if (complain & tf_error)
1514 error ("invalid use of non-static member function");
1520 /* If EXP is a reference to a bitfield, and the type of EXP does not
1521 match the declared type of the bitfield, return the declared type
1522 of the bitfield. Otherwise, return NULL_TREE. */
1525 is_bitfield_expr_with_lowered_type (const_tree exp)
1527 switch (TREE_CODE (exp))
1530 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1531 ? TREE_OPERAND (exp, 1)
1532 : TREE_OPERAND (exp, 0)))
1534 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1537 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1541 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1547 field = TREE_OPERAND (exp, 1);
1548 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1550 if (same_type_ignoring_top_level_qualifiers_p
1551 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1553 return DECL_BIT_FIELD_TYPE (field);
1557 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1558 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1559 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1567 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1568 bitfield with a lowered type, the type of EXP is returned, rather
1572 unlowered_expr_type (const_tree exp)
1576 type = is_bitfield_expr_with_lowered_type (exp);
1578 type = TREE_TYPE (exp);
1583 /* Perform the conversions in [expr] that apply when an lvalue appears
1584 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1585 function-to-pointer conversions. In addition, manifest constants
1586 are replaced by their values, and bitfield references are converted
1587 to their declared types.
1589 Although the returned value is being used as an rvalue, this
1590 function does not wrap the returned expression in a
1591 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1592 that the return value is no longer an lvalue. */
1595 decay_conversion (tree exp)
1598 enum tree_code code;
1600 type = TREE_TYPE (exp);
1601 if (type == error_mark_node)
1602 return error_mark_node;
1604 if (type_unknown_p (exp))
1606 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1607 return error_mark_node;
1610 exp = decl_constant_value (exp);
1611 if (error_operand_p (exp))
1612 return error_mark_node;
1614 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1615 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1616 code = TREE_CODE (type);
1617 if (code == VOID_TYPE)
1619 error ("void value not ignored as it ought to be");
1620 return error_mark_node;
1622 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1623 return error_mark_node;
1624 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1625 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1626 if (code == ARRAY_TYPE)
1631 if (TREE_CODE (exp) == INDIRECT_REF)
1632 return build_nop (build_pointer_type (TREE_TYPE (type)),
1633 TREE_OPERAND (exp, 0));
1635 if (TREE_CODE (exp) == COMPOUND_EXPR)
1637 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1638 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1639 TREE_OPERAND (exp, 0), op1);
1643 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1645 error ("invalid use of non-lvalue array");
1646 return error_mark_node;
1649 ptrtype = build_pointer_type (TREE_TYPE (type));
1651 if (TREE_CODE (exp) == VAR_DECL)
1653 if (!cxx_mark_addressable (exp))
1654 return error_mark_node;
1655 adr = build_nop (ptrtype, build_address (exp));
1658 /* This way is better for a COMPONENT_REF since it can
1659 simplify the offset for a component. */
1660 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1661 return cp_convert (ptrtype, adr);
1664 /* If a bitfield is used in a context where integral promotion
1665 applies, then the caller is expected to have used
1666 default_conversion. That function promotes bitfields correctly
1667 before calling this function. At this point, if we have a
1668 bitfield referenced, we may assume that is not subject to
1669 promotion, and that, therefore, the type of the resulting rvalue
1670 is the declared type of the bitfield. */
1671 exp = convert_bitfield_to_declared_type (exp);
1673 /* We do not call rvalue() here because we do not want to wrap EXP
1674 in a NON_LVALUE_EXPR. */
1678 Non-class rvalues always have cv-unqualified types. */
1679 type = TREE_TYPE (exp);
1680 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1681 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1686 /* Perform preparatory conversions, as part of the "usual arithmetic
1687 conversions". In particular, as per [expr]:
1689 Whenever an lvalue expression appears as an operand of an
1690 operator that expects the rvalue for that operand, the
1691 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1692 standard conversions are applied to convert the expression to an
1695 In addition, we perform integral promotions here, as those are
1696 applied to both operands to a binary operator before determining
1697 what additional conversions should apply. */
1700 default_conversion (tree exp)
1702 /* Check for target-specific promotions. */
1703 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
1705 exp = cp_convert (promoted_type, exp);
1706 /* Perform the integral promotions first so that bitfield
1707 expressions (which may promote to "int", even if the bitfield is
1708 declared "unsigned") are promoted correctly. */
1709 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1710 exp = perform_integral_promotions (exp);
1711 /* Perform the other conversions. */
1712 exp = decay_conversion (exp);
1717 /* EXPR is an expression with an integral or enumeration type.
1718 Perform the integral promotions in [conv.prom], and return the
1722 perform_integral_promotions (tree expr)
1729 If the bitfield has an enumerated type, it is treated as any
1730 other value of that type for promotion purposes. */
1731 type = is_bitfield_expr_with_lowered_type (expr);
1732 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1733 type = TREE_TYPE (expr);
1734 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1735 promoted_type = type_promotes_to (type);
1736 if (type != promoted_type)
1737 expr = cp_convert (promoted_type, expr);
1741 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1742 decay_conversion to one. */
1745 string_conv_p (const_tree totype, const_tree exp, int warn)
1749 if (TREE_CODE (totype) != POINTER_TYPE)
1752 t = TREE_TYPE (totype);
1753 if (!same_type_p (t, char_type_node)
1754 && !same_type_p (t, char16_type_node)
1755 && !same_type_p (t, char32_type_node)
1756 && !same_type_p (t, wchar_type_node))
1759 if (TREE_CODE (exp) == STRING_CST)
1761 /* Make sure that we don't try to convert between char and wide chars. */
1762 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1767 /* Is this a string constant which has decayed to 'const char *'? */
1768 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1769 if (!same_type_p (TREE_TYPE (exp), t))
1772 if (TREE_CODE (exp) != ADDR_EXPR
1773 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1777 /* This warning is not very useful, as it complains about printf. */
1779 warning (OPT_Wwrite_strings,
1780 "deprecated conversion from string constant to %qT",
1786 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1787 can, for example, use as an lvalue. This code used to be in
1788 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1789 expressions, where we're dealing with aggregates. But now it's again only
1790 called from unary_complex_lvalue. The case (in particular) that led to
1791 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1795 rationalize_conditional_expr (enum tree_code code, tree t,
1796 tsubst_flags_t complain)
1798 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1799 the first operand is always the one to be used if both operands
1800 are equal, so we know what conditional expression this used to be. */
1801 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1803 tree op0 = TREE_OPERAND (t, 0);
1804 tree op1 = TREE_OPERAND (t, 1);
1806 /* The following code is incorrect if either operand side-effects. */
1807 gcc_assert (!TREE_SIDE_EFFECTS (op0)
1808 && !TREE_SIDE_EFFECTS (op1));
1810 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1811 ? LE_EXPR : GE_EXPR),
1812 op0, TREE_CODE (op0),
1813 op1, TREE_CODE (op1),
1814 /*overloaded_p=*/NULL,
1816 cp_build_unary_op (code, op0, 0, complain),
1817 cp_build_unary_op (code, op1, 0, complain),
1822 build_conditional_expr (TREE_OPERAND (t, 0),
1823 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
1825 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
1830 /* Given the TYPE of an anonymous union field inside T, return the
1831 FIELD_DECL for the field. If not found return NULL_TREE. Because
1832 anonymous unions can nest, we must also search all anonymous unions
1833 that are directly reachable. */
1836 lookup_anon_field (tree t, tree type)
1840 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1842 if (TREE_STATIC (field))
1844 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1847 /* If we find it directly, return the field. */
1848 if (DECL_NAME (field) == NULL_TREE
1849 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1854 /* Otherwise, it could be nested, search harder. */
1855 if (DECL_NAME (field) == NULL_TREE
1856 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1858 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1866 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1867 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1868 non-NULL, it indicates the path to the base used to name MEMBER.
1869 If PRESERVE_REFERENCE is true, the expression returned will have
1870 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1871 returned will have the type referred to by the reference.
1873 This function does not perform access control; that is either done
1874 earlier by the parser when the name of MEMBER is resolved to MEMBER
1875 itself, or later when overload resolution selects one of the
1876 functions indicated by MEMBER. */
1879 build_class_member_access_expr (tree object, tree member,
1880 tree access_path, bool preserve_reference,
1881 tsubst_flags_t complain)
1885 tree result = NULL_TREE;
1887 if (error_operand_p (object) || error_operand_p (member))
1888 return error_mark_node;
1890 gcc_assert (DECL_P (member) || BASELINK_P (member));
1894 The type of the first expression shall be "class object" (of a
1896 object_type = TREE_TYPE (object);
1897 if (!currently_open_class (object_type)
1898 && !complete_type_or_else (object_type, object))
1899 return error_mark_node;
1900 if (!CLASS_TYPE_P (object_type))
1902 if (complain & tf_error)
1903 error ("request for member %qD in %qE, which is of non-class type %qT",
1904 member, object, object_type);
1905 return error_mark_node;
1908 /* The standard does not seem to actually say that MEMBER must be a
1909 member of OBJECT_TYPE. However, that is clearly what is
1911 if (DECL_P (member))
1913 member_scope = DECL_CLASS_CONTEXT (member);
1915 if (TREE_DEPRECATED (member))
1916 warn_deprecated_use (member, NULL_TREE);
1919 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
1920 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1921 presently be the anonymous union. Go outwards until we find a
1922 type related to OBJECT_TYPE. */
1923 while (ANON_AGGR_TYPE_P (member_scope)
1924 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1926 member_scope = TYPE_CONTEXT (member_scope);
1927 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1929 if (complain & tf_error)
1931 if (TREE_CODE (member) == FIELD_DECL)
1932 error ("invalid use of nonstatic data member %qE", member);
1934 error ("%qD is not a member of %qT", member, object_type);
1936 return error_mark_node;
1939 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1940 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1941 in the front end; only _DECLs and _REFs are lvalues in the back end. */
1943 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1945 object = cp_build_indirect_ref (temp, NULL, complain);
1948 /* In [expr.ref], there is an explicit list of the valid choices for
1949 MEMBER. We check for each of those cases here. */
1950 if (TREE_CODE (member) == VAR_DECL)
1952 /* A static data member. */
1954 /* If OBJECT has side-effects, they are supposed to occur. */
1955 if (TREE_SIDE_EFFECTS (object))
1956 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1958 else if (TREE_CODE (member) == FIELD_DECL)
1960 /* A non-static data member. */
1965 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1966 && integer_zerop (TREE_OPERAND (object, 0)));
1968 /* Convert OBJECT to the type of MEMBER. */
1969 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1970 TYPE_MAIN_VARIANT (member_scope)))
1975 binfo = lookup_base (access_path ? access_path : object_type,
1976 member_scope, ba_unique, &kind);
1977 if (binfo == error_mark_node)
1978 return error_mark_node;
1980 /* It is invalid to try to get to a virtual base of a
1981 NULL object. The most common cause is invalid use of
1983 if (null_object_p && kind == bk_via_virtual)
1985 if (complain & tf_error)
1987 error ("invalid access to non-static data member %qD of "
1990 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1992 return error_mark_node;
1995 /* Convert to the base. */
1996 object = build_base_path (PLUS_EXPR, object, binfo,
1998 /* If we found the base successfully then we should be able
1999 to convert to it successfully. */
2000 gcc_assert (object != error_mark_node);
2003 /* Complain about other invalid uses of offsetof, even though they will
2004 give the right answer. Note that we complain whether or not they
2005 actually used the offsetof macro, since there's no way to know at this
2006 point. So we just give a warning, instead of a pedwarn. */
2007 /* Do not produce this warning for base class field references, because
2008 we know for a fact that didn't come from offsetof. This does occur
2009 in various testsuite cases where a null object is passed where a
2010 vtable access is required. */
2011 if (null_object_p && warn_invalid_offsetof
2012 && CLASSTYPE_NON_POD_P (object_type)
2013 && !DECL_FIELD_IS_BASE (member)
2015 && (complain & tf_warning))
2017 warning (OPT_Winvalid_offsetof,
2018 "invalid access to non-static data member %qD "
2019 " of NULL object", member);
2020 warning (OPT_Winvalid_offsetof,
2021 "(perhaps the %<offsetof%> macro was used incorrectly)");
2024 /* If MEMBER is from an anonymous aggregate, we have converted
2025 OBJECT so that it refers to the class containing the
2026 anonymous union. Generate a reference to the anonymous union
2027 itself, and recur to find MEMBER. */
2028 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2029 /* When this code is called from build_field_call, the
2030 object already has the type of the anonymous union.
2031 That is because the COMPONENT_REF was already
2032 constructed, and was then disassembled before calling
2033 build_field_call. After the function-call code is
2034 cleaned up, this waste can be eliminated. */
2035 && (!same_type_ignoring_top_level_qualifiers_p
2036 (TREE_TYPE (object), DECL_CONTEXT (member))))
2038 tree anonymous_union;
2040 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2041 DECL_CONTEXT (member));
2042 object = build_class_member_access_expr (object,
2044 /*access_path=*/NULL_TREE,
2049 /* Compute the type of the field, as described in [expr.ref]. */
2050 type_quals = TYPE_UNQUALIFIED;
2051 member_type = TREE_TYPE (member);
2052 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2054 type_quals = (cp_type_quals (member_type)
2055 | cp_type_quals (object_type));
2057 /* A field is const (volatile) if the enclosing object, or the
2058 field itself, is const (volatile). But, a mutable field is
2059 not const, even within a const object. */
2060 if (DECL_MUTABLE_P (member))
2061 type_quals &= ~TYPE_QUAL_CONST;
2062 member_type = cp_build_qualified_type (member_type, type_quals);
2065 result = build3 (COMPONENT_REF, member_type, object, member,
2067 result = fold_if_not_in_template (result);
2069 /* Mark the expression const or volatile, as appropriate. Even
2070 though we've dealt with the type above, we still have to mark the
2071 expression itself. */
2072 if (type_quals & TYPE_QUAL_CONST)
2073 TREE_READONLY (result) = 1;
2074 if (type_quals & TYPE_QUAL_VOLATILE)
2075 TREE_THIS_VOLATILE (result) = 1;
2077 else if (BASELINK_P (member))
2079 /* The member is a (possibly overloaded) member function. */
2083 /* If the MEMBER is exactly one static member function, then we
2084 know the type of the expression. Otherwise, we must wait
2085 until overload resolution has been performed. */
2086 functions = BASELINK_FUNCTIONS (member);
2087 if (TREE_CODE (functions) == FUNCTION_DECL
2088 && DECL_STATIC_FUNCTION_P (functions))
2089 type = TREE_TYPE (functions);
2091 type = unknown_type_node;
2092 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2093 base. That will happen when the function is called. */
2094 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2096 else if (TREE_CODE (member) == CONST_DECL)
2098 /* The member is an enumerator. */
2100 /* If OBJECT has side-effects, they are supposed to occur. */
2101 if (TREE_SIDE_EFFECTS (object))
2102 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2107 if (complain & tf_error)
2108 error ("invalid use of %qD", member);
2109 return error_mark_node;
2112 if (!preserve_reference)
2115 If E2 is declared to have type "reference to T", then ... the
2116 type of E1.E2 is T. */
2117 result = convert_from_reference (result);
2122 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2123 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2126 lookup_destructor (tree object, tree scope, tree dtor_name)
2128 tree object_type = TREE_TYPE (object);
2129 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2132 if (scope && !check_dtor_name (scope, dtor_type))
2134 error ("qualified type %qT does not match destructor name ~%qT",
2136 return error_mark_node;
2138 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2140 /* In a template, names we can't find a match for are still accepted
2141 destructor names, and we check them here. */
2142 if (check_dtor_name (object_type, dtor_type))
2143 dtor_type = object_type;
2146 error ("object type %qT does not match destructor name ~%qT",
2147 object_type, dtor_type);
2148 return error_mark_node;
2152 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2154 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2155 TYPE_MAIN_VARIANT (object_type), dtor_type);
2156 return error_mark_node;
2158 expr = lookup_member (dtor_type, complete_dtor_identifier,
2159 /*protect=*/1, /*want_type=*/false);
2160 expr = (adjust_result_of_qualified_name_lookup
2161 (expr, dtor_type, object_type));
2165 /* An expression of the form "A::template B" has been resolved to
2166 DECL. Issue a diagnostic if B is not a template or template
2170 check_template_keyword (tree decl)
2172 /* The standard says:
2176 If a name prefixed by the keyword template is not a member
2177 template, the program is ill-formed.
2179 DR 228 removed the restriction that the template be a member
2182 DR 96, if accepted would add the further restriction that explicit
2183 template arguments must be provided if the template keyword is
2184 used, but, as of 2005-10-16, that DR is still in "drafting". If
2185 this DR is accepted, then the semantic checks here can be
2186 simplified, as the entity named must in fact be a template
2187 specialization, rather than, as at present, a set of overloaded
2188 functions containing at least one template function. */
2189 if (TREE_CODE (decl) != TEMPLATE_DECL
2190 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2192 if (!is_overloaded_fn (decl))
2193 permerror (input_location, "%qD is not a template", decl);
2198 if (BASELINK_P (fns))
2199 fns = BASELINK_FUNCTIONS (fns);
2202 tree fn = OVL_CURRENT (fns);
2203 if (TREE_CODE (fn) == TEMPLATE_DECL
2204 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2206 if (TREE_CODE (fn) == FUNCTION_DECL
2207 && DECL_USE_TEMPLATE (fn)
2208 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2210 fns = OVL_NEXT (fns);
2213 permerror (input_location, "%qD is not a template", decl);
2218 /* This function is called by the parser to process a class member
2219 access expression of the form OBJECT.NAME. NAME is a node used by
2220 the parser to represent a name; it is not yet a DECL. It may,
2221 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2222 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2223 there is no reason to do the lookup twice, so the parser keeps the
2224 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2225 be a template via the use of the "A::template B" syntax. */
2228 finish_class_member_access_expr (tree object, tree name, bool template_p,
2229 tsubst_flags_t complain)
2234 tree access_path = NULL_TREE;
2235 tree orig_object = object;
2236 tree orig_name = name;
2238 if (object == error_mark_node || name == error_mark_node)
2239 return error_mark_node;
2241 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2242 if (!objc_is_public (object, name))
2243 return error_mark_node;
2245 object_type = TREE_TYPE (object);
2247 if (processing_template_decl)
2249 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2250 dependent_type_p (object_type)
2251 /* If NAME is just an IDENTIFIER_NODE, then the expression
2253 || TREE_CODE (object) == IDENTIFIER_NODE
2254 /* If NAME is "f<args>", where either 'f' or 'args' is
2255 dependent, then the expression is dependent. */
2256 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2257 && dependent_template_id_p (TREE_OPERAND (name, 0),
2258 TREE_OPERAND (name, 1)))
2259 /* If NAME is "T::X" where "T" is dependent, then the
2260 expression is dependent. */
2261 || (TREE_CODE (name) == SCOPE_REF
2262 && TYPE_P (TREE_OPERAND (name, 0))
2263 && dependent_type_p (TREE_OPERAND (name, 0))))
2264 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2265 object = build_non_dependent_expr (object);
2270 The type of the first expression shall be "class object" (of a
2272 if (!currently_open_class (object_type)
2273 && !complete_type_or_else (object_type, object))
2274 return error_mark_node;
2275 if (!CLASS_TYPE_P (object_type))
2277 if (complain & tf_error)
2278 error ("request for member %qD in %qE, which is of non-class type %qT",
2279 name, object, object_type);
2280 return error_mark_node;
2283 if (BASELINK_P (name))
2284 /* A member function that has already been looked up. */
2288 bool is_template_id = false;
2289 tree template_args = NULL_TREE;
2292 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2294 is_template_id = true;
2295 template_args = TREE_OPERAND (name, 1);
2296 name = TREE_OPERAND (name, 0);
2298 if (TREE_CODE (name) == OVERLOAD)
2299 name = DECL_NAME (get_first_fn (name));
2300 else if (DECL_P (name))
2301 name = DECL_NAME (name);
2304 if (TREE_CODE (name) == SCOPE_REF)
2306 /* A qualified name. The qualifying class or namespace `S'
2307 has already been looked up; it is either a TYPE or a
2309 scope = TREE_OPERAND (name, 0);
2310 name = TREE_OPERAND (name, 1);
2312 /* If SCOPE is a namespace, then the qualified name does not
2313 name a member of OBJECT_TYPE. */
2314 if (TREE_CODE (scope) == NAMESPACE_DECL)
2316 if (complain & tf_error)
2317 error ("%<%D::%D%> is not a member of %qT",
2318 scope, name, object_type);
2319 return error_mark_node;
2322 gcc_assert (CLASS_TYPE_P (scope));
2323 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2324 || TREE_CODE (name) == BIT_NOT_EXPR);
2326 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2327 access_path = lookup_base (object_type, scope, ba_check, NULL);
2328 if (access_path == error_mark_node)
2329 return error_mark_node;
2332 if (complain & tf_error)
2333 error ("%qT is not a base of %qT", scope, object_type);
2334 return error_mark_node;
2340 access_path = object_type;
2343 if (TREE_CODE (name) == BIT_NOT_EXPR)
2344 member = lookup_destructor (object, scope, name);
2347 /* Look up the member. */
2348 member = lookup_member (access_path, name, /*protect=*/1,
2349 /*want_type=*/false);
2350 if (member == NULL_TREE)
2352 if (complain & tf_error)
2353 error ("%qD has no member named %qE", object_type, name);
2354 return error_mark_node;
2356 if (member == error_mark_node)
2357 return error_mark_node;
2362 tree templ = member;
2364 if (BASELINK_P (templ))
2365 templ = lookup_template_function (templ, template_args);
2368 if (complain & tf_error)
2369 error ("%qD is not a member template function", name);
2370 return error_mark_node;
2375 if (TREE_DEPRECATED (member))
2376 warn_deprecated_use (member, NULL_TREE);
2379 check_template_keyword (member);
2381 expr = build_class_member_access_expr (object, member, access_path,
2382 /*preserve_reference=*/false,
2384 if (processing_template_decl && expr != error_mark_node)
2386 if (BASELINK_P (member))
2388 if (TREE_CODE (orig_name) == SCOPE_REF)
2389 BASELINK_QUALIFIED_P (member) = 1;
2392 return build_min_non_dep (COMPONENT_REF, expr,
2393 orig_object, orig_name,
2400 /* Return an expression for the MEMBER_NAME field in the internal
2401 representation of PTRMEM, a pointer-to-member function. (Each
2402 pointer-to-member function type gets its own RECORD_TYPE so it is
2403 more convenient to access the fields by name than by FIELD_DECL.)
2404 This routine converts the NAME to a FIELD_DECL and then creates the
2405 node for the complete expression. */
2408 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2414 /* This code is a stripped down version of
2415 build_class_member_access_expr. It does not work to use that
2416 routine directly because it expects the object to be of class
2418 ptrmem_type = TREE_TYPE (ptrmem);
2419 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2420 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2421 /*want_type=*/false);
2422 member_type = cp_build_qualified_type (TREE_TYPE (member),
2423 cp_type_quals (ptrmem_type));
2424 return fold_build3 (COMPONENT_REF, member_type,
2425 ptrmem, member, NULL_TREE);
2428 /* Given an expression PTR for a pointer, return an expression
2429 for the value pointed to.
2430 ERRORSTRING is the name of the operator to appear in error messages.
2432 This function may need to overload OPERATOR_FNNAME.
2433 Must also handle REFERENCE_TYPEs for C++. */
2436 build_x_indirect_ref (tree expr, const char *errorstring,
2437 tsubst_flags_t complain)
2439 tree orig_expr = expr;
2442 if (processing_template_decl)
2444 if (type_dependent_expression_p (expr))
2445 return build_min_nt (INDIRECT_REF, expr);
2446 expr = build_non_dependent_expr (expr);
2449 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2450 NULL_TREE, /*overloaded_p=*/NULL, complain);
2452 rval = cp_build_indirect_ref (expr, errorstring, complain);
2454 if (processing_template_decl && rval != error_mark_node)
2455 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2460 /* Helper function called from c-common. */
2462 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2463 tree ptr, const char *errorstring)
2465 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2469 cp_build_indirect_ref (tree ptr, const char *errorstring,
2470 tsubst_flags_t complain)
2474 if (ptr == error_mark_node)
2475 return error_mark_node;
2477 if (ptr == current_class_ptr)
2478 return current_class_ref;
2480 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2481 ? ptr : decay_conversion (ptr));
2482 type = TREE_TYPE (pointer);
2484 if (POINTER_TYPE_P (type))
2488 If the type of the expression is "pointer to T," the type
2489 of the result is "T."
2491 We must use the canonical variant because certain parts of
2492 the back end, like fold, do pointer comparisons between
2494 tree t = canonical_type_variant (TREE_TYPE (type));
2496 if (CONVERT_EXPR_P (ptr)
2497 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2499 /* If a warning is issued, mark it to avoid duplicates from
2500 the backend. This only needs to be done at
2501 warn_strict_aliasing > 2. */
2502 if (warn_strict_aliasing > 2)
2503 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2504 type, TREE_OPERAND (ptr, 0)))
2505 TREE_NO_WARNING (ptr) = 1;
2508 if (VOID_TYPE_P (t))
2510 /* A pointer to incomplete type (other than cv void) can be
2511 dereferenced [expr.unary.op]/1 */
2512 if (complain & tf_error)
2513 error ("%qT is not a pointer-to-object type", type);
2514 return error_mark_node;
2516 else if (TREE_CODE (pointer) == ADDR_EXPR
2517 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2518 /* The POINTER was something like `&x'. We simplify `*&x' to
2520 return TREE_OPERAND (pointer, 0);
2523 tree ref = build1 (INDIRECT_REF, t, pointer);
2525 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2526 so that we get the proper error message if the result is used
2527 to assign to. Also, &* is supposed to be a no-op. */
2528 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2529 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2530 TREE_SIDE_EFFECTS (ref)
2531 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2535 else if (!(complain & tf_error))
2536 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2538 /* `pointer' won't be an error_mark_node if we were given a
2539 pointer to member, so it's cool to check for this here. */
2540 else if (TYPE_PTR_TO_MEMBER_P (type))
2541 error ("invalid use of %qs on pointer to member", errorstring);
2542 else if (pointer != error_mark_node)
2545 error ("invalid type argument of %qs", errorstring);
2547 error ("invalid type argument");
2549 return error_mark_node;
2552 /* This handles expressions of the form "a[i]", which denotes
2555 This is logically equivalent in C to *(a+i), but we may do it differently.
2556 If A is a variable or a member, we generate a primitive ARRAY_REF.
2557 This avoids forcing the array out of registers, and can work on
2558 arrays that are not lvalues (for example, members of structures returned
2561 If INDEX is of some user-defined type, it must be converted to
2562 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2563 will inherit the type of the array, which will be some pointer type.
2565 LOC is the location to use in building the array reference. */
2568 build_array_ref (tree array, tree idx, location_t loc)
2574 error_at (loc, "subscript missing in array reference");
2575 return error_mark_node;
2578 if (TREE_TYPE (array) == error_mark_node
2579 || TREE_TYPE (idx) == error_mark_node)
2580 return error_mark_node;
2582 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2584 switch (TREE_CODE (array))
2588 tree value = build_array_ref (TREE_OPERAND (array, 1), idx, loc);
2589 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2590 TREE_OPERAND (array, 0), value);
2591 SET_EXPR_LOCATION (ret, loc);
2596 ret = build_conditional_expr
2597 (TREE_OPERAND (array, 0),
2598 build_array_ref (TREE_OPERAND (array, 1), idx, loc),
2599 build_array_ref (TREE_OPERAND (array, 2), idx, loc),
2600 tf_warning_or_error);
2601 protected_set_expr_location (ret, loc);
2608 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2612 warn_array_subscript_with_type_char (idx);
2614 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2616 error_at (loc, "array subscript is not an integer");
2617 return error_mark_node;
2620 /* Apply integral promotions *after* noticing character types.
2621 (It is unclear why we do these promotions -- the standard
2622 does not say that we should. In fact, the natural thing would
2623 seem to be to convert IDX to ptrdiff_t; we're performing
2624 pointer arithmetic.) */
2625 idx = perform_integral_promotions (idx);
2627 /* An array that is indexed by a non-constant
2628 cannot be stored in a register; we must be able to do
2629 address arithmetic on its address.
2630 Likewise an array of elements of variable size. */
2631 if (TREE_CODE (idx) != INTEGER_CST
2632 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2633 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2636 if (!cxx_mark_addressable (array))
2637 return error_mark_node;
2640 /* An array that is indexed by a constant value which is not within
2641 the array bounds cannot be stored in a register either; because we
2642 would get a crash in store_bit_field/extract_bit_field when trying
2643 to access a non-existent part of the register. */
2644 if (TREE_CODE (idx) == INTEGER_CST
2645 && TYPE_DOMAIN (TREE_TYPE (array))
2646 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2648 if (!cxx_mark_addressable (array))
2649 return error_mark_node;
2652 if (!lvalue_p (array))
2653 pedwarn (loc, OPT_pedantic,
2654 "ISO C++ forbids subscripting non-lvalue array");
2656 /* Note in C++ it is valid to subscript a `register' array, since
2657 it is valid to take the address of something with that
2658 storage specification. */
2662 while (TREE_CODE (foo) == COMPONENT_REF)
2663 foo = TREE_OPERAND (foo, 0);
2664 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2665 warning_at (loc, OPT_Wextra,
2666 "subscripting array declared %<register%>");
2669 type = TREE_TYPE (TREE_TYPE (array));
2670 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2671 /* Array ref is const/volatile if the array elements are
2672 or if the array is.. */
2673 TREE_READONLY (rval)
2674 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2675 TREE_SIDE_EFFECTS (rval)
2676 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2677 TREE_THIS_VOLATILE (rval)
2678 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2679 ret = require_complete_type (fold_if_not_in_template (rval));
2680 protected_set_expr_location (ret, loc);
2685 tree ar = default_conversion (array);
2686 tree ind = default_conversion (idx);
2688 /* Put the integer in IND to simplify error checking. */
2689 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2696 if (ar == error_mark_node)
2699 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2701 error_at (loc, "subscripted value is neither array nor pointer");
2702 return error_mark_node;
2704 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2706 error_at (loc, "array subscript is not an integer");
2707 return error_mark_node;
2710 warn_array_subscript_with_type_char (idx);
2712 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2714 tf_warning_or_error),
2716 tf_warning_or_error);
2717 protected_set_expr_location (ret, loc);
2722 /* Resolve a pointer to member function. INSTANCE is the object
2723 instance to use, if the member points to a virtual member.
2725 This used to avoid checking for virtual functions if basetype
2726 has no virtual functions, according to an earlier ANSI draft.
2727 With the final ISO C++ rules, such an optimization is
2728 incorrect: A pointer to a derived member can be static_cast
2729 to pointer-to-base-member, as long as the dynamic object
2730 later has the right member. */
2733 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2735 if (TREE_CODE (function) == OFFSET_REF)
2736 function = TREE_OPERAND (function, 1);
2738 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2740 tree idx, delta, e1, e2, e3, vtbl, basetype;
2741 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2743 tree instance_ptr = *instance_ptrptr;
2744 tree instance_save_expr = 0;
2745 if (instance_ptr == error_mark_node)
2747 if (TREE_CODE (function) == PTRMEM_CST)
2749 /* Extracting the function address from a pmf is only
2750 allowed with -Wno-pmf-conversions. It only works for
2752 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2753 e1 = convert (fntype, e1);
2758 error ("object missing in use of %qE", function);
2759 return error_mark_node;
2763 if (TREE_SIDE_EFFECTS (instance_ptr))
2764 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2766 if (TREE_SIDE_EFFECTS (function))
2767 function = save_expr (function);
2769 /* Start by extracting all the information from the PMF itself. */
2770 e3 = pfn_from_ptrmemfunc (function);
2771 delta = delta_from_ptrmemfunc (function);
2772 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2773 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2775 case ptrmemfunc_vbit_in_pfn:
2776 e1 = cp_build_binary_op (input_location,
2777 BIT_AND_EXPR, idx, integer_one_node,
2778 tf_warning_or_error);
2779 idx = cp_build_binary_op (input_location,
2780 MINUS_EXPR, idx, integer_one_node,
2781 tf_warning_or_error);
2784 case ptrmemfunc_vbit_in_delta:
2785 e1 = cp_build_binary_op (input_location,
2786 BIT_AND_EXPR, delta, integer_one_node,
2787 tf_warning_or_error);
2788 delta = cp_build_binary_op (input_location,
2789 RSHIFT_EXPR, delta, integer_one_node,
2790 tf_warning_or_error);
2797 /* Convert down to the right base before using the instance. A
2798 special case is that in a pointer to member of class C, C may
2799 be incomplete. In that case, the function will of course be
2800 a member of C, and no conversion is required. In fact,
2801 lookup_base will fail in that case, because incomplete
2802 classes do not have BINFOs. */
2803 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2804 if (!same_type_ignoring_top_level_qualifiers_p
2805 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2807 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2808 basetype, ba_check, NULL);
2809 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2811 if (instance_ptr == error_mark_node)
2812 return error_mark_node;
2814 /* ...and then the delta in the PMF. */
2815 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2816 instance_ptr, fold_convert (sizetype, delta));
2818 /* Hand back the adjusted 'this' argument to our caller. */
2819 *instance_ptrptr = instance_ptr;
2821 /* Next extract the vtable pointer from the object. */
2822 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2824 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2825 /* If the object is not dynamic the access invokes undefined
2826 behavior. As it is not executed in this case silence the
2827 spurious warnings it may provoke. */
2828 TREE_NO_WARNING (vtbl) = 1;
2830 /* Finally, extract the function pointer from the vtable. */
2831 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2832 fold_convert (sizetype, idx));
2833 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2834 TREE_CONSTANT (e2) = 1;
2836 /* When using function descriptors, the address of the
2837 vtable entry is treated as a function pointer. */
2838 if (TARGET_VTABLE_USES_DESCRIPTORS)
2839 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2840 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2841 tf_warning_or_error));
2843 e2 = fold_convert (TREE_TYPE (e3), e2);
2844 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2846 /* Make sure this doesn't get evaluated first inside one of the
2847 branches of the COND_EXPR. */
2848 if (instance_save_expr)
2849 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2850 instance_save_expr, e1);
2857 /* Used by the C-common bits. */
2859 build_function_call (tree function, tree params)
2861 return cp_build_function_call (function, params, tf_warning_or_error);
2864 /* Used by the C-common bits. */
2866 build_function_call_vec (tree function, VEC(tree,gc) *params,
2867 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
2869 VEC(tree,gc) *orig_params = params;
2870 tree ret = cp_build_function_call_vec (function, ¶ms,
2871 tf_warning_or_error);
2873 /* cp_build_function_call_vec can reallocate PARAMS by adding
2874 default arguments. That should never happen here. Verify
2876 gcc_assert (params == orig_params);
2881 /* Build a function call using a tree list of arguments. */
2884 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2889 vec = make_tree_vector ();
2890 for (; params != NULL_TREE; params = TREE_CHAIN (params))
2891 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
2892 ret = cp_build_function_call_vec (function, &vec, complain);
2893 release_tree_vector (vec);
2897 /* Build a function call using a vector of arguments. PARAMS may be
2898 NULL if there are no parameters. This changes the contents of
2902 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
2903 tsubst_flags_t complain)
2905 tree fntype, fndecl;
2906 tree name = NULL_TREE;
2908 tree original = function;
2912 VEC(tree,gc) *allocated = NULL;
2915 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2916 expressions, like those used for ObjC messenger dispatches. */
2917 if (params != NULL && !VEC_empty (tree, *params))
2918 function = objc_rewrite_function_call (function,
2919 VEC_index (tree, *params, 0));
2921 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2922 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2923 if (TREE_CODE (function) == NOP_EXPR
2924 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2925 function = TREE_OPERAND (function, 0);
2927 if (TREE_CODE (function) == FUNCTION_DECL)
2929 name = DECL_NAME (function);
2931 mark_used (function);
2934 /* Convert anything with function type to a pointer-to-function. */
2935 if (DECL_MAIN_P (function) && (complain & tf_error))
2936 pedwarn (input_location, OPT_pedantic,
2937 "ISO C++ forbids calling %<::main%> from within program");
2939 function = build_addr_func (function);
2945 function = build_addr_func (function);
2948 if (function == error_mark_node)
2949 return error_mark_node;
2951 fntype = TREE_TYPE (function);
2953 if (TYPE_PTRMEMFUNC_P (fntype))
2955 if (complain & tf_error)
2956 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2957 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2958 original, original);
2959 return error_mark_node;
2962 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2963 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2965 if (!((TREE_CODE (fntype) == POINTER_TYPE
2966 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2968 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2970 if (complain & tf_error)
2971 error ("%qE cannot be used as a function", original);
2972 return error_mark_node;
2975 /* fntype now gets the type of function pointed to. */
2976 fntype = TREE_TYPE (fntype);
2977 parm_types = TYPE_ARG_TYPES (fntype);
2981 allocated = make_tree_vector ();
2982 params = &allocated;
2985 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
2988 return error_mark_node;
2990 argarray = VEC_address (tree, *params);
2992 /* Check for errors in format strings and inappropriately
2994 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2997 ret = build_cxx_call (function, nargs, argarray);
2999 if (allocated != NULL)
3000 release_tree_vector (allocated);
3005 /* Convert the actual parameter expressions in the list VALUES to the
3006 types in the list TYPELIST. The converted expressions are stored
3007 back in the VALUES vector.
3008 If parmdecls is exhausted, or when an element has NULL as its type,
3009 perform the default conversions.
3011 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3013 This is also where warnings about wrong number of args are generated.
3015 Returns the actual number of arguments processed (which might be less
3016 than the length of the vector), or -1 on error.
3018 In C++, unspecified trailing parameters can be filled in with their
3019 default arguments, if such were specified. Do so here. */
3022 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3023 int flags, tsubst_flags_t complain)
3026 const char *called_thing = 0;
3029 /* Argument passing is always copy-initialization. */
3030 flags |= LOOKUP_ONLYCONVERTING;
3034 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3036 if (DECL_NAME (fndecl) == NULL_TREE
3037 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3038 called_thing = "constructor";
3040 called_thing = "member function";
3043 called_thing = "function";
3046 for (i = 0, typetail = typelist;
3047 i < VEC_length (tree, *values);
3050 tree type = typetail ? TREE_VALUE (typetail) : 0;
3051 tree val = VEC_index (tree, *values, i);
3053 if (val == error_mark_node || type == error_mark_node)
3056 if (type == void_type_node)
3058 if (complain & tf_error)
3062 error ("too many arguments to %s %q+#D",
3063 called_thing, fndecl);
3064 error ("at this point in file");
3067 error ("too many arguments to function");
3074 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3075 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3076 if (TREE_CODE (val) == NOP_EXPR
3077 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3078 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3079 val = TREE_OPERAND (val, 0);
3081 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3083 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3084 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3085 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3086 val = decay_conversion (val);
3089 if (val == error_mark_node)
3094 /* Formal parm type is specified by a function prototype. */
3097 if (!COMPLETE_TYPE_P (complete_type (type)))
3099 if (complain & tf_error)
3102 error ("parameter %P of %qD has incomplete type %qT",
3105 error ("parameter %P has incomplete type %qT", i, type);
3107 parmval = error_mark_node;
3111 parmval = convert_for_initialization
3112 (NULL_TREE, type, val, flags,
3113 "argument passing", fndecl, i, complain);
3114 parmval = convert_for_arg_passing (type, parmval);
3117 if (parmval == error_mark_node)
3120 VEC_replace (tree, *values, i, parmval);
3124 if (fndecl && DECL_BUILT_IN (fndecl)
3125 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3126 /* Don't do ellipsis conversion for __built_in_constant_p
3127 as this will result in spurious warnings for non-POD
3129 val = require_complete_type (val);
3131 val = convert_arg_to_ellipsis (val);
3133 VEC_replace (tree, *values, i, val);
3137 typetail = TREE_CHAIN (typetail);
3140 if (typetail != 0 && typetail != void_list_node)
3142 /* See if there are default arguments that can be used. Because
3143 we hold default arguments in the FUNCTION_TYPE (which is so
3144 wrong), we can see default parameters here from deduced
3145 contexts (and via typeof) for indirect function calls.
3146 Fortunately we know whether we have a function decl to
3147 provide default arguments in a language conformant
3149 if (fndecl && TREE_PURPOSE (typetail)
3150 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3152 for (; typetail != void_list_node; ++i)
3155 = convert_default_arg (TREE_VALUE (typetail),
3156 TREE_PURPOSE (typetail),
3159 if (parmval == error_mark_node)
3162 VEC_safe_push (tree, gc, *values, parmval);
3163 typetail = TREE_CHAIN (typetail);
3164 /* ends with `...'. */
3165 if (typetail == NULL_TREE)
3171 if (complain & tf_error)
3175 error ("too few arguments to %s %q+#D",
3176 called_thing, fndecl);
3177 error ("at this point in file");
3180 error ("too few arguments to function");
3189 /* Build a binary-operation expression, after performing default
3190 conversions on the operands. CODE is the kind of expression to
3191 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3192 are the tree codes which correspond to ARG1 and ARG2 when issuing
3193 warnings about possibly misplaced parentheses. They may differ
3194 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3195 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3196 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3197 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3198 ARG2_CODE as ERROR_MARK. */
3201 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3202 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3203 tsubst_flags_t complain)
3212 if (processing_template_decl)
3214 if (type_dependent_expression_p (arg1)
3215 || type_dependent_expression_p (arg2))
3216 return build_min_nt (code, arg1, arg2);
3217 arg1 = build_non_dependent_expr (arg1);
3218 arg2 = build_non_dependent_expr (arg2);
3221 if (code == DOTSTAR_EXPR)
3222 expr = build_m_component_ref (arg1, arg2);
3224 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3225 overloaded_p, complain);
3227 /* Check for cases such as x+y<<z which users are likely to
3228 misinterpret. But don't warn about obj << x + y, since that is a
3229 common idiom for I/O. */
3230 if (warn_parentheses
3231 && !processing_template_decl
3232 && !error_operand_p (arg1)
3233 && !error_operand_p (arg2)
3234 && (code != LSHIFT_EXPR
3235 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3236 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3238 if (processing_template_decl && expr != error_mark_node)
3239 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3244 /* Build and return an ARRAY_REF expression. */
3247 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3249 tree orig_arg1 = arg1;
3250 tree orig_arg2 = arg2;
3253 if (processing_template_decl)
3255 if (type_dependent_expression_p (arg1)
3256 || type_dependent_expression_p (arg2))
3257 return build_min_nt (ARRAY_REF, arg1, arg2,
3258 NULL_TREE, NULL_TREE);
3259 arg1 = build_non_dependent_expr (arg1);
3260 arg2 = build_non_dependent_expr (arg2);
3263 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3264 /*overloaded_p=*/NULL, complain);
3266 if (processing_template_decl && expr != error_mark_node)
3267 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3268 NULL_TREE, NULL_TREE);
3272 /* For the c-common bits. */
3274 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3275 int convert_p ATTRIBUTE_UNUSED)
3277 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3281 /* Build a binary-operation expression without default conversions.
3282 CODE is the kind of expression to build.
3283 LOCATION is the location_t of the operator in the source code.
3284 This function differs from `build' in several ways:
3285 the data type of the result is computed and recorded in it,
3286 warnings are generated if arg data types are invalid,
3287 special handling for addition and subtraction of pointers is known,
3288 and some optimization is done (operations on narrow ints
3289 are done in the narrower type when that gives the same result).
3290 Constant folding is also done before the result is returned.
3292 Note that the operands will never have enumeral types
3293 because either they have just had the default conversions performed
3294 or they have both just been converted to some other type in which
3295 the arithmetic is to be done.
3297 C++: must do special pointer arithmetic when implementing
3298 multiple inheritance, and deal with pointer to member functions. */
3301 cp_build_binary_op (location_t location,
3302 enum tree_code code, tree orig_op0, tree orig_op1,
3303 tsubst_flags_t complain)
3306 enum tree_code code0, code1;
3308 const char *invalid_op_diag;
3310 /* Expression code to give to the expression when it is built.
3311 Normally this is CODE, which is what the caller asked for,
3312 but in some special cases we change it. */
3313 enum tree_code resultcode = code;
3315 /* Data type in which the computation is to be performed.
3316 In the simplest cases this is the common type of the arguments. */
3317 tree result_type = NULL;
3319 /* Nonzero means operands have already been type-converted
3320 in whatever way is necessary.
3321 Zero means they need to be converted to RESULT_TYPE. */
3324 /* Nonzero means create the expression with this type, rather than
3326 tree build_type = 0;
3328 /* Nonzero means after finally constructing the expression
3329 convert it to this type. */
3330 tree final_type = 0;
3334 /* Nonzero if this is an operation like MIN or MAX which can
3335 safely be computed in short if both args are promoted shorts.
3336 Also implies COMMON.
3337 -1 indicates a bitwise operation; this makes a difference
3338 in the exact conditions for when it is safe to do the operation
3339 in a narrower mode. */
3342 /* Nonzero if this is a comparison operation;
3343 if both args are promoted shorts, compare the original shorts.
3344 Also implies COMMON. */
3345 int short_compare = 0;
3347 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3350 /* True if both operands have arithmetic type. */
3351 bool arithmetic_types_p;
3353 /* Apply default conversions. */
3357 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3358 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3359 || code == TRUTH_XOR_EXPR)
3361 if (!really_overloaded_fn (op0))
3362 op0 = decay_conversion (op0);
3363 if (!really_overloaded_fn (op1))
3364 op1 = decay_conversion (op1);
3368 if (!really_overloaded_fn (op0))
3369 op0 = default_conversion (op0);
3370 if (!really_overloaded_fn (op1))
3371 op1 = default_conversion (op1);
3374 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3375 STRIP_TYPE_NOPS (op0);
3376 STRIP_TYPE_NOPS (op1);
3378 /* DTRT if one side is an overloaded function, but complain about it. */
3379 if (type_unknown_p (op0))
3381 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3382 if (t != error_mark_node)
3384 if (complain & tf_error)
3385 permerror (input_location, "assuming cast to type %qT from overloaded function",
3390 if (type_unknown_p (op1))
3392 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3393 if (t != error_mark_node)
3395 if (complain & tf_error)
3396 permerror (input_location, "assuming cast to type %qT from overloaded function",
3402 type0 = TREE_TYPE (op0);
3403 type1 = TREE_TYPE (op1);
3405 /* The expression codes of the data types of the arguments tell us
3406 whether the arguments are integers, floating, pointers, etc. */
3407 code0 = TREE_CODE (type0);
3408 code1 = TREE_CODE (type1);
3410 /* If an error was already reported for one of the arguments,
3411 avoid reporting another error. */
3413 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3414 return error_mark_node;
3416 if ((invalid_op_diag
3417 = targetm.invalid_binary_op (code, type0, type1)))
3419 error (invalid_op_diag);
3420 return error_mark_node;
3426 /* Subtraction of two similar pointers.
3427 We must subtract them as integers, then divide by object size. */
3428 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3429 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3431 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3432 /* In all other cases except pointer - int, the usual arithmetic
3434 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3439 /* The pointer - int case is just like pointer + int; fall
3442 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3443 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3447 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3448 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3449 if (processing_template_decl)
3451 result_type = TREE_TYPE (ptr_operand);
3454 return cp_pointer_int_sum (code,
3465 case TRUNC_DIV_EXPR:
3467 case FLOOR_DIV_EXPR:
3468 case ROUND_DIV_EXPR:
3469 case EXACT_DIV_EXPR:
3470 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3471 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3472 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3473 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3475 enum tree_code tcode0 = code0, tcode1 = code1;
3477 warn_for_div_by_zero (location, op1);
3479 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3480 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3481 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3482 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3484 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3485 resultcode = RDIV_EXPR;
3487 /* When dividing two signed integers, we have to promote to int.
3488 unless we divide by a constant != -1. Note that default
3489 conversion will have been performed on the operands at this
3490 point, so we have to dig out the original type to find out if
3492 shorten = ((TREE_CODE (op0) == NOP_EXPR
3493 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3494 || (TREE_CODE (op1) == INTEGER_CST
3495 && ! integer_all_onesp (op1)));
3504 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3505 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3506 && !VECTOR_FLOAT_TYPE_P (type0)
3507 && !VECTOR_FLOAT_TYPE_P (type1)))
3511 case TRUNC_MOD_EXPR:
3512 case FLOOR_MOD_EXPR:
3513 warn_for_div_by_zero (location, op1);
3515 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3516 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3517 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3519 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3521 /* Although it would be tempting to shorten always here, that loses
3522 on some targets, since the modulo instruction is undefined if the
3523 quotient can't be represented in the computation mode. We shorten
3524 only if unsigned or if dividing by something we know != -1. */
3525 shorten = ((TREE_CODE (op0) == NOP_EXPR
3526 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3527 || (TREE_CODE (op1) == INTEGER_CST
3528 && ! integer_all_onesp (op1)));
3533 case TRUTH_ANDIF_EXPR:
3534 case TRUTH_ORIF_EXPR:
3535 case TRUTH_AND_EXPR:
3537 result_type = boolean_type_node;
3540 /* Shift operations: result has same type as first operand;
3541 always convert second operand to int.
3542 Also set SHORT_SHIFT if shifting rightward. */
3545 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3547 result_type = type0;
3548 if (TREE_CODE (op1) == INTEGER_CST)
3550 if (tree_int_cst_lt (op1, integer_zero_node))
3552 if (complain & tf_warning)
3553 warning (0, "right shift count is negative");
3557 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3558 && (complain & tf_warning))
3559 warning (0, "right shift count >= width of type");
3562 /* Convert the shift-count to an integer, regardless of
3563 size of value being shifted. */
3564 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3565 op1 = cp_convert (integer_type_node, op1);
3566 /* Avoid converting op1 to result_type later. */
3572 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3574 result_type = type0;
3575 if (TREE_CODE (op1) == INTEGER_CST)
3577 if (tree_int_cst_lt (op1, integer_zero_node))
3579 if (complain & tf_warning)
3580 warning (0, "left shift count is negative");
3582 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3584 if (complain & tf_warning)
3585 warning (0, "left shift count >= width of type");
3588 /* Convert the shift-count to an integer, regardless of
3589 size of value being shifted. */
3590 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3591 op1 = cp_convert (integer_type_node, op1);
3592 /* Avoid converting op1 to result_type later. */
3599 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3601 result_type = type0;
3602 if (TREE_CODE (op1) == INTEGER_CST)
3604 if (tree_int_cst_lt (op1, integer_zero_node))
3606 if (complain & tf_warning)
3607 warning (0, (code == LROTATE_EXPR)
3608 ? G_("left rotate count is negative")
3609 : G_("right rotate count is negative"));
3611 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3613 if (complain & tf_warning)
3614 warning (0, (code == LROTATE_EXPR)
3615 ? G_("left rotate count >= width of type")
3616 : G_("right rotate count >= width of type"));
3619 /* Convert the shift-count to an integer, regardless of
3620 size of value being shifted. */
3621 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3622 op1 = cp_convert (integer_type_node, op1);
3628 if ((complain & tf_warning)
3629 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3630 warning (OPT_Wfloat_equal,
3631 "comparing floating point with == or != is unsafe");
3632 if ((complain & tf_warning)
3633 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3634 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3635 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3637 build_type = boolean_type_node;
3638 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3639 || code0 == COMPLEX_TYPE)
3640 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3641 || code1 == COMPLEX_TYPE))
3643 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3644 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3645 result_type = composite_pointer_type (type0, type1, op0, op1,
3646 "comparison", complain);
3647 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3648 && null_ptr_cst_p (op1))
3650 if (TREE_CODE (op0) == ADDR_EXPR
3651 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3653 if (complain & tf_warning)
3654 warning (OPT_Waddress, "the address of %qD will never be NULL",
3655 TREE_OPERAND (op0, 0));
3657 result_type = type0;
3659 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3660 && null_ptr_cst_p (op0))
3662 if (TREE_CODE (op1) == ADDR_EXPR
3663 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3665 if (complain & tf_warning)
3666 warning (OPT_Waddress, "the address of %qD will never be NULL",
3667 TREE_OPERAND (op1, 0));
3669 result_type = type1;
3671 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3673 result_type = type0;
3674 if (complain & tf_error)
3675 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3677 return error_mark_node;
3679 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3681 result_type = type1;
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 (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3689 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3690 == ptrmemfunc_vbit_in_delta)
3692 tree pfn0 = pfn_from_ptrmemfunc (op0);
3693 tree delta0 = delta_from_ptrmemfunc (op0);
3694 tree e1 = cp_build_binary_op (location,
3697 fold_convert (TREE_TYPE (pfn0),
3700 tree e2 = cp_build_binary_op (location,
3705 e2 = cp_build_binary_op (location,
3706 EQ_EXPR, e2, integer_zero_node,
3708 op0 = cp_build_binary_op (location,
3709 TRUTH_ANDIF_EXPR, e1, e2,
3711 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3715 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3716 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3718 result_type = TREE_TYPE (op0);
3720 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3721 return cp_build_binary_op (location, code, op1, op0, complain);
3722 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3725 /* E will be the final comparison. */
3727 /* E1 and E2 are for scratch. */
3735 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3738 if (!same_type_p (TREE_TYPE (op0), type))
3739 op0 = cp_convert_and_check (type, op0);
3740 if (!same_type_p (TREE_TYPE (op1), type))
3741 op1 = cp_convert_and_check (type, op1);
3743 if (op0 == error_mark_node || op1 == error_mark_node)
3744 return error_mark_node;
3746 if (TREE_SIDE_EFFECTS (op0))
3747 op0 = save_expr (op0);
3748 if (TREE_SIDE_EFFECTS (op1))
3749 op1 = save_expr (op1);
3751 pfn0 = pfn_from_ptrmemfunc (op0);
3752 pfn1 = pfn_from_ptrmemfunc (op1);
3753 delta0 = delta_from_ptrmemfunc (op0);
3754 delta1 = delta_from_ptrmemfunc (op1);
3755 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3756 == ptrmemfunc_vbit_in_delta)
3761 && ((op0.delta == op1.delta)
3762 || (!op0.pfn && op0.delta & 1 == 0
3763 && op1.delta & 1 == 0))
3765 The reason for the `!op0.pfn' bit is that a NULL
3766 pointer-to-member is any member with a zero PFN and
3767 LSB of the DELTA field is 0. */
3769 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3773 e1 = cp_build_binary_op (location,
3774 EQ_EXPR, e1, integer_zero_node,
3776 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3780 e2 = cp_build_binary_op (location,
3781 EQ_EXPR, e2, integer_zero_node,
3783 e1 = cp_build_binary_op (location,
3784 TRUTH_ANDIF_EXPR, e2, e1,
3786 e2 = cp_build_binary_op (location, EQ_EXPR,
3788 fold_convert (TREE_TYPE (pfn0),
3791 e2 = cp_build_binary_op (location,
3792 TRUTH_ANDIF_EXPR, e2, e1, complain);
3793 e1 = cp_build_binary_op (location,
3794 EQ_EXPR, delta0, delta1, complain);
3795 e1 = cp_build_binary_op (location,
3796 TRUTH_ORIF_EXPR, e1, e2, complain);
3803 && (!op0.pfn || op0.delta == op1.delta))
3805 The reason for the `!op0.pfn' bit is that a NULL
3806 pointer-to-member is any member with a zero PFN; the
3807 DELTA field is unspecified. */
3809 e1 = cp_build_binary_op (location,
3810 EQ_EXPR, delta0, delta1, complain);
3811 e2 = cp_build_binary_op (location,
3814 fold_convert (TREE_TYPE (pfn0),
3817 e1 = cp_build_binary_op (location,
3818 TRUTH_ORIF_EXPR, e1, e2, complain);
3820 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3821 e = cp_build_binary_op (location,
3822 TRUTH_ANDIF_EXPR, e2, e1, complain);
3823 if (code == EQ_EXPR)
3825 return cp_build_binary_op (location,
3826 EQ_EXPR, e, integer_zero_node, complain);
3830 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3831 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3833 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3834 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3842 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3843 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3845 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3846 result_type = composite_pointer_type (type0, type1, op0, op1,
3847 "comparison", complain);
3854 if (TREE_CODE (orig_op0) == STRING_CST
3855 || TREE_CODE (orig_op1) == STRING_CST)
3857 if (complain & tf_warning)
3858 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3861 build_type = boolean_type_node;
3862 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3863 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3865 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3866 result_type = composite_pointer_type (type0, type1, op0, op1,
3867 "comparison", complain);
3868 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3869 && integer_zerop (op1))
3870 result_type = type0;
3871 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3872 && integer_zerop (op0))
3873 result_type = type1;
3874 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3876 result_type = type0;
3877 if (complain & tf_error)
3878 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3880 return error_mark_node;
3882 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3884 result_type = type1;
3885 if (complain & tf_error)
3886 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3888 return error_mark_node;
3892 case UNORDERED_EXPR:
3899 build_type = integer_type_node;
3900 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3902 if (complain & tf_error)
3903 error ("unordered comparison on non-floating point argument");
3904 return error_mark_node;
3913 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3914 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3915 || code1 == COMPLEX_TYPE)))
3916 arithmetic_types_p = 1;
3919 arithmetic_types_p = 0;
3920 /* Vector arithmetic is only allowed when both sides are vectors. */
3921 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3923 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3924 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3927 binary_op_error (location, code, type0, type1);
3928 return error_mark_node;
3930 arithmetic_types_p = 1;
3933 /* Determine the RESULT_TYPE, if it is not already known. */
3935 && arithmetic_types_p
3936 && (shorten || common || short_compare))
3937 result_type = cp_common_type (type0, type1);
3941 if (complain & tf_error)
3942 error ("invalid operands of types %qT and %qT to binary %qO",
3943 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3944 return error_mark_node;
3947 /* If we're in a template, the only thing we need to know is the
3949 if (processing_template_decl)
3951 /* Since the middle-end checks the type when doing a build2, we
3952 need to build the tree in pieces. This built tree will never
3953 get out of the front-end as we replace it when instantiating
3955 tree tmp = build2 (resultcode,
3956 build_type ? build_type : result_type,
3958 TREE_OPERAND (tmp, 0) = op0;
3962 if (arithmetic_types_p)
3964 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3966 /* For certain operations (which identify themselves by shorten != 0)
3967 if both args were extended from the same smaller type,
3968 do the arithmetic in that type and then extend.
3970 shorten !=0 and !=1 indicates a bitwise operation.
3971 For them, this optimization is safe only if
3972 both args are zero-extended or both are sign-extended.
3973 Otherwise, we might change the result.
3974 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3975 but calculated in (unsigned short) it would be (unsigned short)-1. */
3977 if (shorten && none_complex)
3979 final_type = result_type;
3980 result_type = shorten_binary_op (result_type, op0, op1,
3984 /* Comparison operations are shortened too but differently.
3985 They identify themselves by setting short_compare = 1. */
3989 /* Don't write &op0, etc., because that would prevent op0
3990 from being kept in a register.
3991 Instead, make copies of the our local variables and
3992 pass the copies by reference, then copy them back afterward. */
3993 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3994 enum tree_code xresultcode = resultcode;
3996 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3998 return cp_convert (boolean_type_node, val);
3999 op0 = xop0, op1 = xop1;
4001 resultcode = xresultcode;
4004 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4005 && warn_sign_compare
4006 /* Do not warn until the template is instantiated; we cannot
4007 bound the ranges of the arguments until that point. */
4008 && !processing_template_decl
4009 && (complain & tf_warning))
4011 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4012 result_type, resultcode);
4016 /* Issue warnings about peculiar, but valid, uses of NULL. */
4017 if ((orig_op0 == null_node || orig_op1 == null_node)
4018 /* It's reasonable to use pointer values as operands of &&
4019 and ||, so NULL is no exception. */
4020 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
4021 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
4022 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
4023 && code != EQ_EXPR && code != NE_EXPR)
4024 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
4025 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
4026 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
4027 && (complain & tf_warning))
4028 /* Some sort of arithmetic operation involving NULL was
4029 performed. Note that pointer-difference and pointer-addition
4030 have already been handled above, and so we don't end up here in
4032 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
4035 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4036 Then the expression will be built.
4037 It will be given type FINAL_TYPE if that is nonzero;
4038 otherwise, it will be given type RESULT_TYPE. */
4041 if (TREE_TYPE (op0) != result_type)
4042 op0 = cp_convert_and_check (result_type, op0);
4043 if (TREE_TYPE (op1) != result_type)
4044 op1 = cp_convert_and_check (result_type, op1);
4046 if (op0 == error_mark_node || op1 == error_mark_node)
4047 return error_mark_node;
4050 if (build_type == NULL_TREE)
4051 build_type = result_type;
4053 result = build2 (resultcode, build_type, op0, op1);
4054 result = fold_if_not_in_template (result);
4055 if (final_type != 0)
4056 result = cp_convert (final_type, result);
4058 if (TREE_OVERFLOW_P (result)
4059 && !TREE_OVERFLOW_P (op0)
4060 && !TREE_OVERFLOW_P (op1))
4061 overflow_warning (result);
4066 /* Return a tree for the sum or difference (RESULTCODE says which)
4067 of pointer PTROP and integer INTOP. */
4070 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4072 tree res_type = TREE_TYPE (ptrop);
4074 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4075 in certain circumstance (when it's valid to do so). So we need
4076 to make sure it's complete. We don't need to check here, if we
4077 can actually complete it at all, as those checks will be done in
4078 pointer_int_sum() anyway. */
4079 complete_type (TREE_TYPE (res_type));
4081 return pointer_int_sum (resultcode, ptrop,
4082 fold_if_not_in_template (intop));
4085 /* Return a tree for the difference of pointers OP0 and OP1.
4086 The resulting tree has type int. */
4089 pointer_diff (tree op0, tree op1, tree ptrtype)
4092 tree restype = ptrdiff_type_node;
4093 tree target_type = TREE_TYPE (ptrtype);
4095 if (!complete_type_or_else (target_type, NULL_TREE))
4096 return error_mark_node;
4098 if (TREE_CODE (target_type) == VOID_TYPE)
4099 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4100 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4101 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4102 if (TREE_CODE (target_type) == METHOD_TYPE)
4103 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4105 /* First do the subtraction as integers;
4106 then drop through to build the divide operator. */
4108 op0 = cp_build_binary_op (input_location,
4110 cp_convert (restype, op0),
4111 cp_convert (restype, op1),
4112 tf_warning_or_error);
4114 /* This generates an error if op1 is a pointer to an incomplete type. */
4115 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4116 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4118 op1 = (TYPE_PTROB_P (ptrtype)
4119 ? size_in_bytes (target_type)
4120 : integer_one_node);
4122 /* Do the division. */
4124 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4125 return fold_if_not_in_template (result);
4128 /* Construct and perhaps optimize a tree representation
4129 for a unary operation. CODE, a tree_code, specifies the operation
4130 and XARG is the operand. */
4133 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4135 tree orig_expr = xarg;
4139 if (processing_template_decl)
4141 if (type_dependent_expression_p (xarg))
4142 return build_min_nt (code, xarg, NULL_TREE);
4144 xarg = build_non_dependent_expr (xarg);
4149 /* [expr.unary.op] says:
4151 The address of an object of incomplete type can be taken.
4153 (And is just the ordinary address operator, not an overloaded
4154 "operator &".) However, if the type is a template
4155 specialization, we must complete the type at this point so that
4156 an overloaded "operator &" will be available if required. */
4157 if (code == ADDR_EXPR
4158 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4159 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4160 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4161 || (TREE_CODE (xarg) == OFFSET_REF)))
4162 /* Don't look for a function. */;
4164 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4165 /*overloaded_p=*/NULL, complain);
4166 if (!exp && code == ADDR_EXPR)
4168 if (is_overloaded_fn (xarg))
4170 tree fn = get_first_fn (xarg);
4171 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4174 (DECL_CONSTRUCTOR_P (fn) ? "constructor" : "destructor");
4175 error ("taking address of %s %qE", type, xarg);
4176 return error_mark_node;
4180 /* A pointer to member-function can be formed only by saying
4182 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4183 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4185 if (TREE_CODE (xarg) != OFFSET_REF
4186 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4188 error ("invalid use of %qE to form a pointer-to-member-function",
4190 if (TREE_CODE (xarg) != OFFSET_REF)
4191 inform (input_location, " a qualified-id is required");
4192 return error_mark_node;
4196 error ("parentheses around %qE cannot be used to form a"
4197 " pointer-to-member-function",
4199 PTRMEM_OK_P (xarg) = 1;
4203 if (TREE_CODE (xarg) == OFFSET_REF)
4205 ptrmem = PTRMEM_OK_P (xarg);
4207 if (!ptrmem && !flag_ms_extensions
4208 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4210 /* A single non-static member, make sure we don't allow a
4211 pointer-to-member. */
4212 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4213 TREE_OPERAND (xarg, 0),
4214 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4215 PTRMEM_OK_P (xarg) = ptrmem;
4218 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4219 warning (0, "taking address of temporary");
4220 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4223 if (processing_template_decl && exp != error_mark_node)
4224 exp = build_min_non_dep (code, exp, orig_expr,
4225 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4226 if (TREE_CODE (exp) == ADDR_EXPR)
4227 PTRMEM_OK_P (exp) = ptrmem;
4231 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4232 constants, where a null value is represented by an INTEGER_CST of
4236 cp_truthvalue_conversion (tree expr)
4238 tree type = TREE_TYPE (expr);
4239 if (TYPE_PTRMEM_P (type))
4240 return build_binary_op (EXPR_LOCATION (expr),
4241 NE_EXPR, expr, integer_zero_node, 1);
4243 return c_common_truthvalue_conversion (input_location, expr);
4246 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4249 condition_conversion (tree expr)
4252 if (processing_template_decl)
4254 t = perform_implicit_conversion (boolean_type_node, expr,
4255 tf_warning_or_error);
4256 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4260 /* Return an ADDR_EXPR giving the address of T. This function
4261 attempts no optimizations or simplifications; it is a low-level
4265 build_address (tree t)
4269 if (error_operand_p (t) || !cxx_mark_addressable (t))
4270 return error_mark_node;
4272 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4277 /* Return a NOP_EXPR converting EXPR to TYPE. */
4280 build_nop (tree type, tree expr)
4282 if (type == error_mark_node || error_operand_p (expr))
4284 return build1 (NOP_EXPR, type, expr);
4287 /* C++: Must handle pointers to members.
4289 Perhaps type instantiation should be extended to handle conversion
4290 from aggregates to types we don't yet know we want? (Or are those
4291 cases typically errors which should be reported?)
4293 NOCONVERT nonzero suppresses the default promotions
4294 (such as from short to int). */
4297 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4298 tsubst_flags_t complain)
4300 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4303 const char *errstring = NULL;
4305 const char *invalid_op_diag;
4307 if (error_operand_p (arg))
4308 return error_mark_node;
4310 if ((invalid_op_diag
4311 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4316 error (invalid_op_diag);
4317 return error_mark_node;
4322 case UNARY_PLUS_EXPR:
4325 int flags = WANT_ARITH | WANT_ENUM;
4326 /* Unary plus (but not unary minus) is allowed on pointers. */
4327 if (code == UNARY_PLUS_EXPR)
4328 flags |= WANT_POINTER;
4329 arg = build_expr_type_conversion (flags, arg, true);
4331 errstring = (code == NEGATE_EXPR
4332 ? "wrong type argument to unary minus"
4333 : "wrong type argument to unary plus");
4336 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4337 arg = perform_integral_promotions (arg);
4339 /* Make sure the result is not an lvalue: a unary plus or minus
4340 expression is always a rvalue. */
4347 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4351 arg = default_conversion (arg);
4353 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4356 errstring = "wrong type argument to bit-complement";
4357 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4358 arg = perform_integral_promotions (arg);
4362 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4363 errstring = "wrong type argument to abs";
4364 else if (!noconvert)
4365 arg = default_conversion (arg);
4369 /* Conjugating a real value is a no-op, but allow it anyway. */
4370 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4371 errstring = "wrong type argument to conjugation";
4372 else if (!noconvert)
4373 arg = default_conversion (arg);
4376 case TRUTH_NOT_EXPR:
4377 arg = perform_implicit_conversion (boolean_type_node, arg,
4379 val = invert_truthvalue (arg);
4380 if (arg != error_mark_node)
4382 errstring = "in argument to unary !";
4389 if (TREE_CODE (arg) == COMPLEX_CST)
4390 return TREE_REALPART (arg);
4391 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4393 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4394 return fold_if_not_in_template (arg);
4400 if (TREE_CODE (arg) == COMPLEX_CST)
4401 return TREE_IMAGPART (arg);
4402 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4404 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4405 return fold_if_not_in_template (arg);
4408 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4410 case PREINCREMENT_EXPR:
4411 case POSTINCREMENT_EXPR:
4412 case PREDECREMENT_EXPR:
4413 case POSTDECREMENT_EXPR:
4414 /* Handle complex lvalues (when permitted)
4415 by reduction to simpler cases. */
4417 val = unary_complex_lvalue (code, arg);
4421 /* Increment or decrement the real part of the value,
4422 and don't change the imaginary part. */
4423 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4427 arg = stabilize_reference (arg);
4428 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4429 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4430 real = cp_build_unary_op (code, real, 1, complain);
4431 if (real == error_mark_node || imag == error_mark_node)
4432 return error_mark_node;
4433 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4437 /* Report invalid types. */
4439 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4442 if (code == PREINCREMENT_EXPR)
4443 errstring ="no pre-increment operator for type";
4444 else if (code == POSTINCREMENT_EXPR)
4445 errstring ="no post-increment operator for type";
4446 else if (code == PREDECREMENT_EXPR)
4447 errstring ="no pre-decrement operator for type";
4449 errstring ="no post-decrement operator for type";
4452 else if (arg == error_mark_node)
4453 return error_mark_node;
4455 /* Report something read-only. */
4457 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4458 || TREE_READONLY (arg))
4460 if (complain & tf_error)
4461 readonly_error (arg, ((code == PREINCREMENT_EXPR
4462 || code == POSTINCREMENT_EXPR)
4463 ? "increment" : "decrement"));
4465 return error_mark_node;
4470 tree declared_type = unlowered_expr_type (arg);
4472 argtype = TREE_TYPE (arg);
4474 /* ARM $5.2.5 last annotation says this should be forbidden. */
4475 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4477 if (complain & tf_error)
4478 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4479 ? G_("ISO C++ forbids incrementing an enum")
4480 : G_("ISO C++ forbids decrementing an enum"));
4482 return error_mark_node;
4485 /* Compute the increment. */
4487 if (TREE_CODE (argtype) == POINTER_TYPE)
4489 tree type = complete_type (TREE_TYPE (argtype));
4491 if (!COMPLETE_OR_VOID_TYPE_P (type))
4493 if (complain & tf_error)
4494 error (((code == PREINCREMENT_EXPR
4495 || code == POSTINCREMENT_EXPR))
4496 ? G_("cannot increment a pointer to incomplete type %qT")
4497 : G_("cannot decrement a pointer to incomplete type %qT"),
4498 TREE_TYPE (argtype));
4500 return error_mark_node;
4502 else if ((pedantic || warn_pointer_arith)
4503 && !TYPE_PTROB_P (argtype))
4505 if (complain & tf_error)
4506 permerror (input_location, (code == PREINCREMENT_EXPR
4507 || code == POSTINCREMENT_EXPR)
4508 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4509 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4512 return error_mark_node;
4515 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4518 inc = integer_one_node;
4520 inc = cp_convert (argtype, inc);
4522 /* Complain about anything else that is not a true lvalue. */
4523 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4524 || code == POSTINCREMENT_EXPR)
4525 ? lv_increment : lv_decrement),
4527 return error_mark_node;
4529 /* Forbid using -- on `bool'. */
4530 if (same_type_p (declared_type, boolean_type_node))
4532 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4534 if (complain & tf_error)
4535 error ("invalid use of Boolean expression as operand "
4536 "to %<operator--%>");
4537 return error_mark_node;
4539 val = boolean_increment (code, arg);
4542 val = build2 (code, TREE_TYPE (arg), arg, inc);
4544 TREE_SIDE_EFFECTS (val) = 1;
4549 /* Note that this operation never does default_conversion
4550 regardless of NOCONVERT. */
4552 argtype = lvalue_type (arg);
4554 if (TREE_CODE (arg) == OFFSET_REF)
4557 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4559 tree type = build_pointer_type (TREE_TYPE (argtype));
4560 arg = build1 (CONVERT_EXPR, type, arg);
4563 else if (pedantic && DECL_MAIN_P (arg))
4566 /* Apparently a lot of autoconf scripts for C++ packages do this,
4567 so only complain if -pedantic. */
4568 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4569 pedwarn (input_location, OPT_pedantic,
4570 "ISO C++ forbids taking address of function %<::main%>");
4571 else if (flag_pedantic_errors)
4572 return error_mark_node;
4575 /* Let &* cancel out to simplify resulting code. */
4576 if (TREE_CODE (arg) == INDIRECT_REF)
4578 /* We don't need to have `current_class_ptr' wrapped in a
4579 NON_LVALUE_EXPR node. */
4580 if (arg == current_class_ref)
4581 return current_class_ptr;
4583 arg = TREE_OPERAND (arg, 0);
4584 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4586 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4587 arg = build1 (CONVERT_EXPR, type, arg);
4590 /* Don't let this be an lvalue. */
4595 /* Uninstantiated types are all functions. Taking the
4596 address of a function is a no-op, so just return the
4599 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4600 || !IDENTIFIER_OPNAME_P (arg));
4602 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4603 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4605 /* They're trying to take the address of a unique non-static
4606 member function. This is ill-formed (except in MS-land),
4607 but let's try to DTRT.
4608 Note: We only handle unique functions here because we don't
4609 want to complain if there's a static overload; non-unique
4610 cases will be handled by instantiate_type. But we need to
4611 handle this case here to allow casts on the resulting PMF.
4612 We could defer this in non-MS mode, but it's easier to give
4613 a useful error here. */
4615 /* Inside constant member functions, the `this' pointer
4616 contains an extra const qualifier. TYPE_MAIN_VARIANT
4617 is used here to remove this const from the diagnostics
4618 and the created OFFSET_REF. */
4619 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4620 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4623 if (! flag_ms_extensions)
4625 tree name = DECL_NAME (fn);
4626 if (!(complain & tf_error))
4627 return error_mark_node;
4628 else if (current_class_type
4629 && TREE_OPERAND (arg, 0) == current_class_ref)
4630 /* An expression like &memfn. */
4631 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4632 " or parenthesized non-static member function to form"
4633 " a pointer to member function. Say %<&%T::%D%>",
4636 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4637 " function to form a pointer to member function."
4641 arg = build_offset_ref (base, fn, /*address_p=*/true);
4645 if (type_unknown_p (arg))
4646 return build1 (ADDR_EXPR, unknown_type_node, arg);
4648 /* Handle complex lvalues (when permitted)
4649 by reduction to simpler cases. */
4650 val = unary_complex_lvalue (code, arg);
4654 switch (TREE_CODE (arg))
4658 case FIX_TRUNC_EXPR:
4659 /* Even if we're not being pedantic, we cannot allow this
4660 extension when we're instantiating in a SFINAE
4662 if (! lvalue_p (arg) && complain == tf_none)
4664 if (complain & tf_error)
4665 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4667 return error_mark_node;
4672 arg = BASELINK_FUNCTIONS (arg);
4676 arg = OVL_CURRENT (arg);
4680 /* Turn a reference to a non-static data member into a
4681 pointer-to-member. */
4686 if (!PTRMEM_OK_P (arg))
4687 return cp_build_unary_op (code, arg, 0, complain);
4689 t = TREE_OPERAND (arg, 1);
4690 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4692 if (complain & tf_error)
4693 error ("cannot create pointer to reference member %qD", t);
4694 return error_mark_node;
4697 type = build_ptrmem_type (context_for_name_lookup (t),
4699 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4707 /* Anything not already handled and not a true memory reference
4709 if (TREE_CODE (argtype) != FUNCTION_TYPE
4710 && TREE_CODE (argtype) != METHOD_TYPE
4711 && TREE_CODE (arg) != OFFSET_REF
4712 && !lvalue_or_else (arg, lv_addressof, complain))
4713 return error_mark_node;
4715 if (argtype != error_mark_node)
4716 argtype = build_pointer_type (argtype);
4718 /* In a template, we are processing a non-dependent expression
4719 so we can just form an ADDR_EXPR with the correct type. */
4720 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4722 val = build_address (arg);
4723 if (TREE_CODE (arg) == OFFSET_REF)
4724 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4726 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4728 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4730 /* We can only get here with a single static member
4732 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4733 && DECL_STATIC_FUNCTION_P (fn));
4735 val = build_address (fn);
4736 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4737 /* Do not lose object's side effects. */
4738 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4739 TREE_OPERAND (arg, 0), val);
4741 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4743 if (complain & tf_error)
4744 error ("attempt to take address of bit-field structure member %qD",
4745 TREE_OPERAND (arg, 1));
4746 return error_mark_node;
4750 tree object = TREE_OPERAND (arg, 0);
4751 tree field = TREE_OPERAND (arg, 1);
4752 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4753 (TREE_TYPE (object), decl_type_context (field)));
4754 val = build_address (arg);
4757 if (TREE_CODE (argtype) == POINTER_TYPE
4758 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4760 build_ptrmemfunc_type (argtype);
4761 val = build_ptrmemfunc (argtype, val, 0,
4762 /*c_cast_p=*/false);
4774 argtype = TREE_TYPE (arg);
4775 return fold_if_not_in_template (build1 (code, argtype, arg));
4778 if (complain & tf_error)
4779 error ("%s", errstring);
4780 return error_mark_node;
4783 /* Hook for the c-common bits that build a unary op. */
4785 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4786 enum tree_code code, tree xarg, int noconvert)
4788 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4791 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4792 for certain kinds of expressions which are not really lvalues
4793 but which we can accept as lvalues.
4795 If ARG is not a kind of expression we can handle, return
4799 unary_complex_lvalue (enum tree_code code, tree arg)
4801 /* Inside a template, making these kinds of adjustments is
4802 pointless; we are only concerned with the type of the
4804 if (processing_template_decl)
4807 /* Handle (a, b) used as an "lvalue". */
4808 if (TREE_CODE (arg) == COMPOUND_EXPR)
4810 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4811 tf_warning_or_error);
4812 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4813 TREE_OPERAND (arg, 0), real_result);
4816 /* Handle (a ? b : c) used as an "lvalue". */
4817 if (TREE_CODE (arg) == COND_EXPR
4818 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4819 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4821 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4822 if (TREE_CODE (arg) == MODIFY_EXPR
4823 || TREE_CODE (arg) == PREINCREMENT_EXPR
4824 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4826 tree lvalue = TREE_OPERAND (arg, 0);
4827 if (TREE_SIDE_EFFECTS (lvalue))
4829 lvalue = stabilize_reference (lvalue);
4830 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4831 lvalue, TREE_OPERAND (arg, 1));
4833 return unary_complex_lvalue
4834 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4837 if (code != ADDR_EXPR)
4840 /* Handle (a = b) used as an "lvalue" for `&'. */
4841 if (TREE_CODE (arg) == MODIFY_EXPR
4842 || TREE_CODE (arg) == INIT_EXPR)
4844 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4845 tf_warning_or_error);
4846 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4848 TREE_NO_WARNING (arg) = 1;
4852 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4853 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4854 || TREE_CODE (arg) == OFFSET_REF)
4857 /* We permit compiler to make function calls returning
4858 objects of aggregate type look like lvalues. */
4862 if (TREE_CODE (targ) == SAVE_EXPR)
4863 targ = TREE_OPERAND (targ, 0);
4865 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4867 if (TREE_CODE (arg) == SAVE_EXPR)
4870 targ = build_cplus_new (TREE_TYPE (arg), arg);
4871 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4874 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4875 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4876 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4879 /* Don't let anything else be handled specially. */
4883 /* Mark EXP saying that we need to be able to take the
4884 address of it; it should not be allocated in a register.
4885 Value is true if successful.
4887 C++: we do not allow `current_class_ptr' to be addressable. */
4890 cxx_mark_addressable (tree exp)
4895 switch (TREE_CODE (x))
4902 x = TREE_OPERAND (x, 0);
4906 if (x == current_class_ptr)
4908 error ("cannot take the address of %<this%>, which is an rvalue expression");
4909 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4915 /* Caller should not be trying to mark initialized
4916 constant fields addressable. */
4917 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4918 || DECL_IN_AGGR_P (x) == 0
4920 || DECL_EXTERNAL (x));
4925 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4926 && !DECL_ARTIFICIAL (x))
4928 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4931 ("address of explicit register variable %qD requested", x);
4934 else if (extra_warnings)
4936 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4938 TREE_ADDRESSABLE (x) = 1;
4942 TREE_ADDRESSABLE (x) = 1;
4946 TREE_ADDRESSABLE (x) = 1;
4950 TREE_ADDRESSABLE (x) = 1;
4951 cxx_mark_addressable (TREE_OPERAND (x, 0));
4959 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4962 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4963 tsubst_flags_t complain)
4965 tree orig_ifexp = ifexp;
4966 tree orig_op1 = op1;
4967 tree orig_op2 = op2;
4970 if (processing_template_decl)
4972 /* The standard says that the expression is type-dependent if
4973 IFEXP is type-dependent, even though the eventual type of the
4974 expression doesn't dependent on IFEXP. */
4975 if (type_dependent_expression_p (ifexp)
4976 /* As a GNU extension, the middle operand may be omitted. */
4977 || (op1 && type_dependent_expression_p (op1))
4978 || type_dependent_expression_p (op2))
4979 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4980 ifexp = build_non_dependent_expr (ifexp);
4982 op1 = build_non_dependent_expr (op1);
4983 op2 = build_non_dependent_expr (op2);
4986 expr = build_conditional_expr (ifexp, op1, op2, complain);
4987 if (processing_template_decl && expr != error_mark_node)
4988 return build_min_non_dep (COND_EXPR, expr,
4989 orig_ifexp, orig_op1, orig_op2);
4993 /* Given a list of expressions, return a compound expression
4994 that performs them all and returns the value of the last of them. */
4996 tree build_x_compound_expr_from_list (tree list, const char *msg)
4998 tree expr = TREE_VALUE (list);
5000 if (TREE_CHAIN (list))
5003 permerror (input_location, "%s expression list treated as compound expression", msg);
5005 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5006 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5007 tf_warning_or_error);
5013 /* Like build_x_compound_expr_from_list, but using a VEC. */
5016 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5018 if (VEC_empty (tree, vec))
5020 else if (VEC_length (tree, vec) == 1)
5021 return VEC_index (tree, vec, 0);
5029 permerror (input_location,
5030 "%s expression list treated as compound expression",
5033 expr = VEC_index (tree, vec, 0);
5034 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5035 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5041 /* Handle overloading of the ',' operator when needed. */
5044 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5047 tree orig_op1 = op1;
5048 tree orig_op2 = op2;
5050 if (processing_template_decl)
5052 if (type_dependent_expression_p (op1)
5053 || type_dependent_expression_p (op2))
5054 return build_min_nt (COMPOUND_EXPR, op1, op2);
5055 op1 = build_non_dependent_expr (op1);
5056 op2 = build_non_dependent_expr (op2);
5059 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5060 /*overloaded_p=*/NULL, complain);
5062 result = cp_build_compound_expr (op1, op2, complain);
5064 if (processing_template_decl && result != error_mark_node)
5065 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5070 /* Like cp_build_compound_expr, but for the c-common bits. */
5073 build_compound_expr (tree lhs, tree rhs)
5075 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5078 /* Build a compound expression. */
5081 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5083 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5085 if (lhs == error_mark_node || rhs == error_mark_node)
5086 return error_mark_node;
5088 if (TREE_CODE (rhs) == TARGET_EXPR)
5090 /* If the rhs is a TARGET_EXPR, then build the compound
5091 expression inside the target_expr's initializer. This
5092 helps the compiler to eliminate unnecessary temporaries. */
5093 tree init = TREE_OPERAND (rhs, 1);
5095 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5096 TREE_OPERAND (rhs, 1) = init;
5101 if (type_unknown_p (rhs))
5103 error ("no context to resolve type of %qE", rhs);
5104 return error_mark_node;
5107 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5110 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5111 casts away constness. CAST gives the type of cast.
5113 ??? This function warns for casting away any qualifier not just
5114 const. We would like to specify exactly what qualifiers are casted
5119 check_for_casting_away_constness (tree src_type, tree dest_type,
5120 enum tree_code cast)
5122 /* C-style casts are allowed to cast away constness. With
5123 WARN_CAST_QUAL, we still want to issue a warning. */
5124 if (cast == CAST_EXPR && !warn_cast_qual)
5127 if (!casts_away_constness (src_type, dest_type))
5133 warning (OPT_Wcast_qual,
5134 "cast from type %qT to type %qT casts away qualifiers",
5135 src_type, dest_type);
5138 case STATIC_CAST_EXPR:
5139 error ("static_cast from type %qT to type %qT casts away qualifiers",
5140 src_type, dest_type);
5143 case REINTERPRET_CAST_EXPR:
5144 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5145 src_type, dest_type);
5152 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5153 (another pointer-to-member type in the same hierarchy) and return
5154 the converted expression. If ALLOW_INVERSE_P is permitted, a
5155 pointer-to-derived may be converted to pointer-to-base; otherwise,
5156 only the other direction is permitted. If C_CAST_P is true, this
5157 conversion is taking place as part of a C-style cast. */
5160 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5163 if (TYPE_PTRMEM_P (type))
5167 if (TREE_CODE (expr) == PTRMEM_CST)
5168 expr = cplus_expand_constant (expr);
5169 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5170 TYPE_PTRMEM_CLASS_TYPE (type),
5173 if (!integer_zerop (delta))
5175 tree cond, op1, op2;
5177 cond = cp_build_binary_op (input_location,
5180 build_int_cst (TREE_TYPE (expr), -1),
5181 tf_warning_or_error);
5182 op1 = build_nop (ptrdiff_type_node, expr);
5183 op2 = cp_build_binary_op (input_location,
5184 PLUS_EXPR, op1, delta,
5185 tf_warning_or_error);
5187 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5191 return build_nop (type, expr);
5194 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5195 allow_inverse_p, c_cast_p);
5198 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5199 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5200 Otherwise, return EXPR unchanged. */
5203 ignore_overflows (tree expr, tree orig)
5205 if (TREE_CODE (expr) == INTEGER_CST
5206 && CONSTANT_CLASS_P (orig)
5207 && TREE_CODE (orig) != STRING_CST
5208 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5210 if (!TREE_OVERFLOW (orig))
5211 /* Ensure constant sharing. */
5212 expr = build_int_cst_wide (TREE_TYPE (expr),
5213 TREE_INT_CST_LOW (expr),
5214 TREE_INT_CST_HIGH (expr));
5217 /* Avoid clobbering a shared constant. */
5218 expr = copy_node (expr);
5219 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5225 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5226 this static_cast is being attempted as one of the possible casts
5227 allowed by a C-style cast. (In that case, accessibility of base
5228 classes is not considered, and it is OK to cast away
5229 constness.) Return the result of the cast. *VALID_P is set to
5230 indicate whether or not the cast was valid. */
5233 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5234 bool *valid_p, tsubst_flags_t complain)
5240 /* Assume the cast is valid. */
5243 intype = TREE_TYPE (expr);
5245 /* Save casted types in the function's used types hash table. */
5246 used_types_insert (type);
5248 /* [expr.static.cast]
5250 An lvalue of type "cv1 B", where B is a class type, can be cast
5251 to type "reference to cv2 D", where D is a class derived (clause
5252 _class.derived_) from B, if a valid standard conversion from
5253 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5254 same cv-qualification as, or greater cv-qualification than, cv1,
5255 and B is not a virtual base class of D. */
5256 /* We check this case before checking the validity of "TYPE t =
5257 EXPR;" below because for this case:
5260 struct D : public B { D(const B&); };
5262 void f() { static_cast<const D&>(b); }
5264 we want to avoid constructing a new D. The standard is not
5265 completely clear about this issue, but our interpretation is
5266 consistent with other compilers. */
5267 if (TREE_CODE (type) == REFERENCE_TYPE
5268 && CLASS_TYPE_P (TREE_TYPE (type))
5269 && CLASS_TYPE_P (intype)
5270 && real_lvalue_p (expr)
5271 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5272 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5273 build_pointer_type (TYPE_MAIN_VARIANT
5274 (TREE_TYPE (type))))
5276 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5280 /* There is a standard conversion from "D*" to "B*" even if "B"
5281 is ambiguous or inaccessible. If this is really a
5282 static_cast, then we check both for inaccessibility and
5283 ambiguity. However, if this is a static_cast being performed
5284 because the user wrote a C-style cast, then accessibility is
5286 base = lookup_base (TREE_TYPE (type), intype,
5287 c_cast_p ? ba_unique : ba_check,
5290 /* Convert from "B*" to "D*". This function will check that "B"
5291 is not a virtual base of "D". */
5292 expr = build_base_path (MINUS_EXPR, build_address (expr),
5293 base, /*nonnull=*/false);
5294 /* Convert the pointer to a reference -- but then remember that
5295 there are no expressions with reference type in C++. */
5296 return convert_from_reference (build_nop (type, expr));
5301 /* [expr.static.cast]
5303 An expression e can be explicitly converted to a type T using a
5304 static_cast of the form static_cast<T>(e) if the declaration T
5305 t(e);" is well-formed, for some invented temporary variable
5307 result = perform_direct_initialization_if_possible (type, expr,
5308 c_cast_p, complain);
5311 result = convert_from_reference (result);
5313 /* Ignore any integer overflow caused by the cast. */
5314 result = ignore_overflows (result, orig);
5316 /* [expr.static.cast]
5318 If T is a reference type, the result is an lvalue; otherwise,
5319 the result is an rvalue. */
5320 if (TREE_CODE (type) != REFERENCE_TYPE)
5321 result = rvalue (result);
5325 /* [expr.static.cast]
5327 Any expression can be explicitly converted to type cv void. */
5328 if (TREE_CODE (type) == VOID_TYPE)
5329 return convert_to_void (expr, /*implicit=*/NULL, complain);
5331 /* [expr.static.cast]
5333 The inverse of any standard conversion sequence (clause _conv_),
5334 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5335 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5336 (_conv.bool_) conversions, can be performed explicitly using
5337 static_cast subject to the restriction that the explicit
5338 conversion does not cast away constness (_expr.const.cast_), and
5339 the following additional rules for specific cases: */
5340 /* For reference, the conversions not excluded are: integral
5341 promotions, floating point promotion, integral conversions,
5342 floating point conversions, floating-integral conversions,
5343 pointer conversions, and pointer to member conversions. */
5346 A value of integral _or enumeration_ type can be explicitly
5347 converted to an enumeration type. */
5348 /* The effect of all that is that any conversion between any two
5349 types which are integral, floating, or enumeration types can be
5351 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
5352 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
5354 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5356 /* Ignore any integer overflow caused by the cast. */
5357 expr = ignore_overflows (expr, orig);
5361 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5362 && CLASS_TYPE_P (TREE_TYPE (type))
5363 && CLASS_TYPE_P (TREE_TYPE (intype))
5364 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5365 (TREE_TYPE (intype))),
5366 build_pointer_type (TYPE_MAIN_VARIANT
5367 (TREE_TYPE (type)))))
5372 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5373 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5374 c_cast_p ? ba_unique : ba_check,
5376 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5379 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5380 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5387 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5388 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5390 if (TYPE_PTRMEM_P (type))
5392 t1 = (build_ptrmem_type
5394 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5395 t2 = (build_ptrmem_type
5397 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5404 if (can_convert (t1, t2) || can_convert (t2, t1))
5407 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5408 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5413 /* [expr.static.cast]
5415 An rvalue of type "pointer to cv void" can be explicitly
5416 converted to a pointer to object type. A value of type pointer
5417 to object converted to "pointer to cv void" and back to the
5418 original pointer type will have its original value. */
5419 if (TREE_CODE (intype) == POINTER_TYPE
5420 && VOID_TYPE_P (TREE_TYPE (intype))
5421 && TYPE_PTROB_P (type))
5424 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5425 return build_nop (type, expr);
5429 return error_mark_node;
5432 /* Return an expression representing static_cast<TYPE>(EXPR). */
5435 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5440 if (type == error_mark_node || expr == error_mark_node)
5441 return error_mark_node;
5443 if (processing_template_decl)
5445 expr = build_min (STATIC_CAST_EXPR, type, expr);
5446 /* We don't know if it will or will not have side effects. */
5447 TREE_SIDE_EFFECTS (expr) = 1;
5448 return convert_from_reference (expr);
5451 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5452 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5453 if (TREE_CODE (type) != REFERENCE_TYPE
5454 && TREE_CODE (expr) == NOP_EXPR
5455 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5456 expr = TREE_OPERAND (expr, 0);
5458 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5463 if (complain & tf_error)
5464 error ("invalid static_cast from type %qT to type %qT",
5465 TREE_TYPE (expr), type);
5466 return error_mark_node;
5469 /* EXPR is an expression with member function or pointer-to-member
5470 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5471 not permitted by ISO C++, but we accept it in some modes. If we
5472 are not in one of those modes, issue a diagnostic. Return the
5473 converted expression. */
5476 convert_member_func_to_ptr (tree type, tree expr)
5481 intype = TREE_TYPE (expr);
5482 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5483 || TREE_CODE (intype) == METHOD_TYPE);
5485 if (pedantic || warn_pmf2ptr)
5486 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5487 "converting from %qT to %qT", intype, type);
5489 if (TREE_CODE (intype) == METHOD_TYPE)
5490 expr = build_addr_func (expr);
5491 else if (TREE_CODE (expr) == PTRMEM_CST)
5492 expr = build_address (PTRMEM_CST_MEMBER (expr));
5495 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5496 decl = build_address (decl);
5497 expr = get_member_function_from_ptrfunc (&decl, expr);
5500 return build_nop (type, expr);
5503 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5504 If C_CAST_P is true, this reinterpret cast is being done as part of
5505 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5506 indicate whether or not reinterpret_cast was valid. */
5509 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5510 bool *valid_p, tsubst_flags_t complain)
5514 /* Assume the cast is invalid. */
5518 if (type == error_mark_node || error_operand_p (expr))
5519 return error_mark_node;
5521 intype = TREE_TYPE (expr);
5523 /* Save casted types in the function's used types hash table. */
5524 used_types_insert (type);
5526 /* [expr.reinterpret.cast]
5527 An lvalue expression of type T1 can be cast to the type
5528 "reference to T2" if an expression of type "pointer to T1" can be
5529 explicitly converted to the type "pointer to T2" using a
5530 reinterpret_cast. */
5531 if (TREE_CODE (type) == REFERENCE_TYPE)
5533 if (! real_lvalue_p (expr))
5535 if (complain & tf_error)
5536 error ("invalid cast of an rvalue expression of type "
5539 return error_mark_node;
5542 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5543 "B" are related class types; the reinterpret_cast does not
5544 adjust the pointer. */
5545 if (TYPE_PTR_P (intype)
5546 && (complain & tf_warning)
5547 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5548 COMPARE_BASE | COMPARE_DERIVED)))
5549 warning (0, "casting %qT to %qT does not dereference pointer",
5552 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5553 if (expr != error_mark_node)
5554 expr = build_reinterpret_cast_1
5555 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5557 if (expr != error_mark_node)
5558 expr = cp_build_indirect_ref (expr, 0, complain);
5562 /* As a G++ extension, we consider conversions from member
5563 functions, and pointers to member functions to
5564 pointer-to-function and pointer-to-void types. If
5565 -Wno-pmf-conversions has not been specified,
5566 convert_member_func_to_ptr will issue an error message. */
5567 if ((TYPE_PTRMEMFUNC_P (intype)
5568 || TREE_CODE (intype) == METHOD_TYPE)
5569 && TYPE_PTR_P (type)
5570 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5571 || VOID_TYPE_P (TREE_TYPE (type))))
5572 return convert_member_func_to_ptr (type, expr);
5574 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5575 array-to-pointer, and function-to-pointer conversions are
5577 expr = decay_conversion (expr);
5579 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5580 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5581 if (TREE_CODE (expr) == NOP_EXPR
5582 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5583 expr = TREE_OPERAND (expr, 0);
5585 if (error_operand_p (expr))
5586 return error_mark_node;
5588 intype = TREE_TYPE (expr);
5590 /* [expr.reinterpret.cast]
5591 A pointer can be converted to any integral type large enough to
5593 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5595 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5597 if (complain & tf_error)
5598 permerror (input_location, "cast from %qT to %qT loses precision",
5601 return error_mark_node;
5604 /* [expr.reinterpret.cast]
5605 A value of integral or enumeration type can be explicitly
5606 converted to a pointer. */
5607 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5610 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5611 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5612 return fold_if_not_in_template (build_nop (type, expr));
5613 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5614 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5619 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5620 /* Warn about possible alignment problems. */
5621 if (STRICT_ALIGNMENT && warn_cast_align
5622 && (complain & tf_warning)
5623 && !VOID_TYPE_P (type)
5624 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5625 && COMPLETE_TYPE_P (TREE_TYPE (type))
5626 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5627 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5628 warning (OPT_Wcast_align, "cast from %qT to %qT "
5629 "increases required alignment of target type", intype, type);
5631 /* We need to strip nops here, because the front end likes to
5632 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5634 if (warn_strict_aliasing <= 2)
5635 strict_aliasing_warning (intype, type, sexpr);
5637 return fold_if_not_in_template (build_nop (type, expr));
5639 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5640 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5642 if (pedantic && (complain & tf_warning))
5643 /* Only issue a warning, as we have always supported this
5644 where possible, and it is necessary in some cases. DR 195
5645 addresses this issue, but as of 2004/10/26 is still in
5647 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5648 return fold_if_not_in_template (build_nop (type, expr));
5650 else if (TREE_CODE (type) == VECTOR_TYPE)
5651 return fold_if_not_in_template (convert_to_vector (type, expr));
5652 else if (TREE_CODE (intype) == VECTOR_TYPE && INTEGRAL_TYPE_P (type))
5653 return fold_if_not_in_template (convert_to_integer (type, expr));
5658 if (complain & tf_error)
5659 error ("invalid cast from type %qT to type %qT", intype, type);
5660 return error_mark_node;
5663 return cp_convert (type, expr);
5667 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5669 if (type == error_mark_node || expr == error_mark_node)
5670 return error_mark_node;
5672 if (processing_template_decl)
5674 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5676 if (!TREE_SIDE_EFFECTS (t)
5677 && type_dependent_expression_p (expr))
5678 /* There might turn out to be side effects inside expr. */
5679 TREE_SIDE_EFFECTS (t) = 1;
5680 return convert_from_reference (t);
5683 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5684 /*valid_p=*/NULL, complain);
5687 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5688 return an appropriate expression. Otherwise, return
5689 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5690 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5691 performing a C-style cast, its value upon return will indicate
5692 whether or not the conversion succeeded. */
5695 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5699 tree reference_type;
5701 /* Callers are responsible for handling error_mark_node as a
5702 destination type. */
5703 gcc_assert (dst_type != error_mark_node);
5704 /* In a template, callers should be building syntactic
5705 representations of casts, not using this machinery. */
5706 gcc_assert (!processing_template_decl);
5708 /* Assume the conversion is invalid. */
5712 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5715 error ("invalid use of const_cast with type %qT, "
5716 "which is not a pointer, "
5717 "reference, nor a pointer-to-data-member type", dst_type);
5718 return error_mark_node;
5721 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5724 error ("invalid use of const_cast with type %qT, which is a pointer "
5725 "or reference to a function type", dst_type);
5726 return error_mark_node;
5729 /* Save casted types in the function's used types hash table. */
5730 used_types_insert (dst_type);
5732 src_type = TREE_TYPE (expr);
5733 /* Expressions do not really have reference types. */
5734 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5735 src_type = TREE_TYPE (src_type);
5737 /* [expr.const.cast]
5739 An lvalue of type T1 can be explicitly converted to an lvalue of
5740 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5741 types) if a pointer to T1 can be explicitly converted to the type
5742 pointer to T2 using a const_cast. */
5743 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5745 reference_type = dst_type;
5746 if (! real_lvalue_p (expr))
5749 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5750 src_type, dst_type);
5751 return error_mark_node;
5753 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5754 src_type = build_pointer_type (src_type);
5758 reference_type = NULL_TREE;
5759 /* If the destination type is not a reference type, the
5760 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5761 conversions are performed. */
5762 src_type = type_decays_to (src_type);
5763 if (src_type == error_mark_node)
5764 return error_mark_node;
5767 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5768 && comp_ptr_ttypes_const (dst_type, src_type))
5773 /* This cast is actually a C-style cast. Issue a warning if
5774 the user is making a potentially unsafe cast. */
5775 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5779 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5780 complain? tf_warning_or_error : tf_none);
5781 expr = build_nop (reference_type, expr);
5782 return convert_from_reference (expr);
5786 expr = decay_conversion (expr);
5787 /* build_c_cast puts on a NOP_EXPR to make the result not an
5788 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5789 non-lvalue context. */
5790 if (TREE_CODE (expr) == NOP_EXPR
5791 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5792 expr = TREE_OPERAND (expr, 0);
5793 return build_nop (dst_type, expr);
5798 error ("invalid const_cast from type %qT to type %qT",
5799 src_type, dst_type);
5800 return error_mark_node;
5804 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5806 if (type == error_mark_node || error_operand_p (expr))
5807 return error_mark_node;
5809 if (processing_template_decl)
5811 tree t = build_min (CONST_CAST_EXPR, type, expr);
5813 if (!TREE_SIDE_EFFECTS (t)
5814 && type_dependent_expression_p (expr))
5815 /* There might turn out to be side effects inside expr. */
5816 TREE_SIDE_EFFECTS (t) = 1;
5817 return convert_from_reference (t);
5820 return build_const_cast_1 (type, expr, complain & tf_error,
5824 /* Like cp_build_c_cast, but for the c-common bits. */
5827 build_c_cast (tree type, tree expr)
5829 return cp_build_c_cast (type, expr, tf_warning_or_error);
5832 /* Build an expression representing an explicit C-style cast to type
5833 TYPE of expression EXPR. */
5836 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5842 if (type == error_mark_node || error_operand_p (expr))
5843 return error_mark_node;
5845 if (processing_template_decl)
5847 tree t = build_min (CAST_EXPR, type,
5848 tree_cons (NULL_TREE, value, NULL_TREE));
5849 /* We don't know if it will or will not have side effects. */
5850 TREE_SIDE_EFFECTS (t) = 1;
5851 return convert_from_reference (t);
5854 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5855 'Class') should always be retained, because this information aids
5856 in method lookup. */
5857 if (objc_is_object_ptr (type)
5858 && objc_is_object_ptr (TREE_TYPE (expr)))
5859 return build_nop (type, expr);
5861 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5862 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5863 if (TREE_CODE (type) != REFERENCE_TYPE
5864 && TREE_CODE (value) == NOP_EXPR
5865 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5866 value = TREE_OPERAND (value, 0);
5868 if (TREE_CODE (type) == ARRAY_TYPE)
5870 /* Allow casting from T1* to T2[] because Cfront allows it.
5871 NIHCL uses it. It is not valid ISO C++ however. */
5872 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5874 if (complain & tf_error)
5875 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5877 return error_mark_node;
5878 type = build_pointer_type (TREE_TYPE (type));
5882 if (complain & tf_error)
5883 error ("ISO C++ forbids casting to an array type %qT", type);
5884 return error_mark_node;
5888 if (TREE_CODE (type) == FUNCTION_TYPE
5889 || TREE_CODE (type) == METHOD_TYPE)
5891 if (complain & tf_error)
5892 error ("invalid cast to function type %qT", type);
5893 return error_mark_node;
5896 /* A C-style cast can be a const_cast. */
5897 result = build_const_cast_1 (type, value, /*complain=*/false,
5902 /* Or a static cast. */
5903 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5904 &valid_p, complain);
5905 /* Or a reinterpret_cast. */
5907 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5908 &valid_p, complain);
5909 /* The static_cast or reinterpret_cast may be followed by a
5912 /* A valid cast may result in errors if, for example, a
5913 conversion to am ambiguous base class is required. */
5914 && !error_operand_p (result))
5918 /* Non-class rvalues always have cv-unqualified type. */
5919 if (!CLASS_TYPE_P (type))
5920 type = TYPE_MAIN_VARIANT (type);
5921 result_type = TREE_TYPE (result);
5922 if (!CLASS_TYPE_P (result_type))
5923 result_type = TYPE_MAIN_VARIANT (result_type);
5924 /* If the type of RESULT does not match TYPE, perform a
5925 const_cast to make it match. If the static_cast or
5926 reinterpret_cast succeeded, we will differ by at most
5927 cv-qualification, so the follow-on const_cast is guaranteed
5929 if (!same_type_p (non_reference (type), non_reference (result_type)))
5931 result = build_const_cast_1 (type, result, false, &valid_p);
5932 gcc_assert (valid_p);
5937 return error_mark_node;
5940 /* For use from the C common bits. */
5942 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5943 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
5944 enum tree_code modifycode, tree rhs,
5945 tree rhs_origtype ATTRIBUTE_UNUSED)
5947 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5950 /* Build an assignment expression of lvalue LHS from value RHS.
5951 MODIFYCODE is the code for a binary operator that we use
5952 to combine the old value of LHS with RHS to get the new value.
5953 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5955 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5958 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5959 tsubst_flags_t complain)
5963 tree lhstype = TREE_TYPE (lhs);
5964 tree olhstype = lhstype;
5965 bool plain_assign = (modifycode == NOP_EXPR);
5967 /* Avoid duplicate error messages from operands that had errors. */
5968 if (error_operand_p (lhs) || error_operand_p (rhs))
5969 return error_mark_node;
5971 /* Handle control structure constructs used as "lvalues". */
5972 switch (TREE_CODE (lhs))
5974 /* Handle --foo = 5; as these are valid constructs in C++. */
5975 case PREDECREMENT_EXPR:
5976 case PREINCREMENT_EXPR:
5977 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5978 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5979 stabilize_reference (TREE_OPERAND (lhs, 0)),
5980 TREE_OPERAND (lhs, 1));
5981 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
5982 modifycode, rhs, complain);
5983 if (newrhs == error_mark_node)
5984 return error_mark_node;
5985 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5987 /* Handle (a, b) used as an "lvalue". */
5989 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5990 modifycode, rhs, complain);
5991 if (newrhs == error_mark_node)
5992 return error_mark_node;
5993 return build2 (COMPOUND_EXPR, lhstype,
5994 TREE_OPERAND (lhs, 0), newrhs);
5997 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5998 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5999 stabilize_reference (TREE_OPERAND (lhs, 0)),
6000 TREE_OPERAND (lhs, 1));
6001 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6003 if (newrhs == error_mark_node)
6004 return error_mark_node;
6005 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6009 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6010 when neither operand has side-effects. */
6011 if (!lvalue_or_else (lhs, lv_assign, complain))
6012 return error_mark_node;
6014 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6015 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6017 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6018 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6020 TREE_OPERAND (lhs, 0),
6021 TREE_OPERAND (lhs, 1)),
6022 TREE_OPERAND (lhs, 0),
6023 TREE_OPERAND (lhs, 1));
6026 /* Handle (a ? b : c) used as an "lvalue". */
6029 /* Produce (a ? (b = rhs) : (c = rhs))
6030 except that the RHS goes through a save-expr
6031 so the code to compute it is only emitted once. */
6033 tree preeval = NULL_TREE;
6035 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6037 if (complain & tf_error)
6038 error ("void value not ignored as it ought to be");
6039 return error_mark_node;
6042 rhs = stabilize_expr (rhs, &preeval);
6044 /* Check this here to avoid odd errors when trying to convert
6045 a throw to the type of the COND_EXPR. */
6046 if (!lvalue_or_else (lhs, lv_assign, complain))
6047 return error_mark_node;
6049 cond = build_conditional_expr
6050 (TREE_OPERAND (lhs, 0),
6051 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6052 modifycode, rhs, complain),
6053 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6054 modifycode, rhs, complain),
6057 if (cond == error_mark_node)
6059 /* Make sure the code to compute the rhs comes out
6060 before the split. */
6062 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6070 if (modifycode == INIT_EXPR)
6072 if (TREE_CODE (rhs) == CONSTRUCTOR)
6074 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6075 /* Call convert to generate an error; see PR 11063. */
6076 rhs = convert (lhstype, rhs);
6077 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6078 TREE_SIDE_EFFECTS (result) = 1;
6081 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6082 /* Do the default thing. */;
6085 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6086 result = build_special_member_call (lhs, complete_ctor_identifier,
6087 &rhs_vec, lhstype, LOOKUP_NORMAL,
6089 release_tree_vector (rhs_vec);
6090 if (result == NULL_TREE)
6091 return error_mark_node;
6097 lhs = require_complete_type (lhs);
6098 if (lhs == error_mark_node)
6099 return error_mark_node;
6101 if (modifycode == NOP_EXPR)
6103 /* `operator=' is not an inheritable operator. */
6104 if (! MAYBE_CLASS_TYPE_P (lhstype))
6105 /* Do the default thing. */;
6108 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6109 lhs, rhs, make_node (NOP_EXPR),
6110 /*overloaded_p=*/NULL,
6112 if (result == NULL_TREE)
6113 return error_mark_node;
6120 /* A binary op has been requested. Combine the old LHS
6121 value with the RHS producing the value we should actually
6122 store into the LHS. */
6123 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6124 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6125 || MAYBE_CLASS_TYPE_P (lhstype)));
6127 lhs = stabilize_reference (lhs);
6128 newrhs = cp_build_binary_op (input_location,
6129 modifycode, lhs, rhs,
6131 if (newrhs == error_mark_node)
6133 if (complain & tf_error)
6134 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6135 TREE_TYPE (lhs), TREE_TYPE (rhs));
6136 return error_mark_node;
6139 /* Now it looks like a plain assignment. */
6140 modifycode = NOP_EXPR;
6142 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6143 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6146 /* The left-hand side must be an lvalue. */
6147 if (!lvalue_or_else (lhs, lv_assign, complain))
6148 return error_mark_node;
6150 /* Warn about modifying something that is `const'. Don't warn if
6151 this is initialization. */
6152 if (modifycode != INIT_EXPR
6153 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6154 /* Functions are not modifiable, even though they are
6156 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6157 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6158 /* If it's an aggregate and any field is const, then it is
6159 effectively const. */
6160 || (CLASS_TYPE_P (lhstype)
6161 && C_TYPE_FIELDS_READONLY (lhstype))))
6163 if (complain & tf_error)
6164 readonly_error (lhs, "assignment");
6166 return error_mark_node;
6169 /* If storing into a structure or union member, it may have been given a
6170 lowered bitfield type. We need to convert to the declared type first,
6171 so retrieve it now. */
6173 olhstype = unlowered_expr_type (lhs);
6175 /* Convert new value to destination type. */
6177 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6181 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6182 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6184 if (complain & tf_error)
6185 error ("incompatible types in assignment of %qT to %qT",
6186 TREE_TYPE (rhs), lhstype);
6187 return error_mark_node;
6190 /* Allow array assignment in compiler-generated code. */
6191 if (!current_function_decl || !DECL_ARTIFICIAL (current_function_decl))
6193 /* This routine is used for both initialization and assignment.
6194 Make sure the diagnostic message differentiates the context. */
6195 if (complain & tf_error)
6197 if (modifycode == INIT_EXPR)
6198 error ("array used as initializer");
6200 error ("invalid array assignment");
6202 return error_mark_node;
6205 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6206 ? 1 + (modifycode != INIT_EXPR): 0;
6207 return build_vec_init (lhs, NULL_TREE, newrhs,
6208 /*explicit_value_init_p=*/false,
6209 from_array, complain);
6212 if (modifycode == INIT_EXPR)
6213 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6214 LOOKUP_ONLYCONVERTING. */
6215 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6216 "initialization", NULL_TREE, 0,
6219 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6220 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6222 if (!same_type_p (lhstype, olhstype))
6223 newrhs = cp_convert_and_check (lhstype, newrhs);
6225 if (modifycode != INIT_EXPR)
6227 if (TREE_CODE (newrhs) == CALL_EXPR
6228 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6229 newrhs = build_cplus_new (lhstype, newrhs);
6231 /* Can't initialize directly from a TARGET_EXPR, since that would
6232 cause the lhs to be constructed twice, and possibly result in
6233 accidental self-initialization. So we force the TARGET_EXPR to be
6234 expanded without a target. */
6235 if (TREE_CODE (newrhs) == TARGET_EXPR)
6236 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6237 TREE_OPERAND (newrhs, 0));
6240 if (newrhs == error_mark_node)
6241 return error_mark_node;
6243 if (c_dialect_objc () && flag_objc_gc)
6245 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6251 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6252 lhstype, lhs, newrhs);
6254 TREE_SIDE_EFFECTS (result) = 1;
6256 TREE_NO_WARNING (result) = 1;
6262 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6263 tsubst_flags_t complain)
6265 if (processing_template_decl)
6266 return build_min_nt (MODOP_EXPR, lhs,
6267 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6269 if (modifycode != NOP_EXPR)
6271 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6272 make_node (modifycode),
6273 /*overloaded_p=*/NULL,
6277 TREE_NO_WARNING (rval) = 1;
6281 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6284 /* Helper function for get_delta_difference which assumes FROM is a base
6285 class of TO. Returns a delta for the conversion of pointer-to-member
6286 of FROM to pointer-to-member of TO. If the conversion is invalid,
6287 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6288 If C_CAST_P is true, this conversion is taking place as part of a C-style
6292 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6297 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6298 if (kind == bk_inaccessible || kind == bk_ambig)
6300 error (" in pointer to member function conversion");
6301 return size_zero_node;
6305 if (kind != bk_via_virtual)
6306 return BINFO_OFFSET (binfo);
6308 /* FROM is a virtual base class of TO. Issue an error or warning
6309 depending on whether or not this is a reinterpret cast. */
6311 error ("pointer to member conversion via virtual base %qT",
6312 BINFO_TYPE (binfo_from_vbase (binfo)));
6314 return size_zero_node;
6321 /* Get difference in deltas for different pointer to member function
6322 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6323 the conversion is invalid, the constant is zero. If
6324 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6325 If C_CAST_P is true this conversion is taking place as part of a
6328 Note that the naming of FROM and TO is kind of backwards; the return
6329 value is what we add to a TO in order to get a FROM. They are named
6330 this way because we call this function to find out how to convert from
6331 a pointer to member of FROM to a pointer to member of TO. */
6334 get_delta_difference (tree from, tree to,
6335 bool allow_inverse_p,
6340 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6341 /* Pointer to member of incomplete class is permitted*/
6342 result = size_zero_node;
6344 result = get_delta_difference_1 (from, to, c_cast_p);
6348 if (!allow_inverse_p)
6350 error_not_base_type (from, to);
6351 error (" in pointer to member conversion");
6352 result = size_zero_node;
6356 result = get_delta_difference_1 (to, from, c_cast_p);
6359 result = size_diffop (size_zero_node, result);
6362 error_not_base_type (from, to);
6363 error (" in pointer to member conversion");
6364 result = size_zero_node;
6369 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6373 /* Return a constructor for the pointer-to-member-function TYPE using
6374 the other components as specified. */
6377 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6382 VEC(constructor_elt, gc) *v;
6384 /* Pull the FIELD_DECLs out of the type. */
6385 pfn_field = TYPE_FIELDS (type);
6386 delta_field = TREE_CHAIN (pfn_field);
6388 /* Make sure DELTA has the type we want. */
6389 delta = convert_and_check (delta_type_node, delta);
6391 /* Convert to the correct target type if necessary. */
6392 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6394 /* Finish creating the initializer. */
6395 v = VEC_alloc(constructor_elt, gc, 2);
6396 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6397 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6398 u = build_constructor (type, v);
6399 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6400 TREE_STATIC (u) = (TREE_CONSTANT (u)
6401 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6403 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6408 /* Build a constructor for a pointer to member function. It can be
6409 used to initialize global variables, local variable, or used
6410 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6413 If FORCE is nonzero, then force this conversion, even if
6414 we would rather not do it. Usually set when using an explicit
6415 cast. A C-style cast is being processed iff C_CAST_P is true.
6417 Return error_mark_node, if something goes wrong. */
6420 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6426 if (error_operand_p (pfn))
6427 return error_mark_node;
6429 pfn_type = TREE_TYPE (pfn);
6430 to_type = build_ptrmemfunc_type (type);
6432 /* Handle multiple conversions of pointer to member functions. */
6433 if (TYPE_PTRMEMFUNC_P (pfn_type))
6435 tree delta = NULL_TREE;
6436 tree npfn = NULL_TREE;
6440 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6441 error ("invalid conversion to type %qT from type %qT",
6444 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6445 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6449 /* We don't have to do any conversion to convert a
6450 pointer-to-member to its own type. But, we don't want to
6451 just return a PTRMEM_CST if there's an explicit cast; that
6452 cast should make the expression an invalid template argument. */
6453 if (TREE_CODE (pfn) != PTRMEM_CST)
6455 if (same_type_p (to_type, pfn_type))
6457 else if (integer_zerop (n))
6458 return build_reinterpret_cast (to_type, pfn,
6459 tf_warning_or_error);
6462 if (TREE_SIDE_EFFECTS (pfn))
6463 pfn = save_expr (pfn);
6465 /* Obtain the function pointer and the current DELTA. */
6466 if (TREE_CODE (pfn) == PTRMEM_CST)
6467 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6470 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6471 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6474 /* Just adjust the DELTA field. */
6475 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6476 (TREE_TYPE (delta), ptrdiff_type_node));
6477 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6478 n = cp_build_binary_op (input_location,
6479 LSHIFT_EXPR, n, integer_one_node,
6480 tf_warning_or_error);
6481 delta = cp_build_binary_op (input_location,
6482 PLUS_EXPR, delta, n, tf_warning_or_error);
6483 return build_ptrmemfunc1 (to_type, delta, npfn);
6486 /* Handle null pointer to member function conversions. */
6487 if (integer_zerop (pfn))
6489 pfn = build_c_cast (type, integer_zero_node);
6490 return build_ptrmemfunc1 (to_type,
6495 if (type_unknown_p (pfn))
6496 return instantiate_type (type, pfn, tf_warning_or_error);
6498 fn = TREE_OPERAND (pfn, 0);
6499 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6500 /* In a template, we will have preserved the
6502 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6503 return make_ptrmem_cst (to_type, fn);
6506 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6509 ??? There is no consistency as to the types returned for the above
6510 values. Some code acts as if it were a sizetype and some as if it were
6511 integer_type_node. */
6514 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6516 tree type = TREE_TYPE (cst);
6517 tree fn = PTRMEM_CST_MEMBER (cst);
6518 tree ptr_class, fn_class;
6520 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6522 /* The class that the function belongs to. */
6523 fn_class = DECL_CONTEXT (fn);
6525 /* The class that we're creating a pointer to member of. */
6526 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6528 /* First, calculate the adjustment to the function's class. */
6529 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6532 if (!DECL_VIRTUAL_P (fn))
6533 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6536 /* If we're dealing with a virtual function, we have to adjust 'this'
6537 again, to point to the base which provides the vtable entry for
6538 fn; the call will do the opposite adjustment. */
6539 tree orig_class = DECL_CONTEXT (fn);
6540 tree binfo = binfo_or_else (orig_class, fn_class);
6541 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6542 *delta, BINFO_OFFSET (binfo));
6543 *delta = fold_if_not_in_template (*delta);
6545 /* We set PFN to the vtable offset at which the function can be
6546 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6547 case delta is shifted left, and then incremented). */
6548 *pfn = DECL_VINDEX (fn);
6549 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6550 TYPE_SIZE_UNIT (vtable_entry_type));
6551 *pfn = fold_if_not_in_template (*pfn);
6553 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6555 case ptrmemfunc_vbit_in_pfn:
6556 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6558 *pfn = fold_if_not_in_template (*pfn);
6561 case ptrmemfunc_vbit_in_delta:
6562 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6563 *delta, integer_one_node);
6564 *delta = fold_if_not_in_template (*delta);
6565 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6566 *delta, integer_one_node);
6567 *delta = fold_if_not_in_template (*delta);
6574 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6575 *pfn = fold_if_not_in_template (*pfn);
6579 /* Return an expression for PFN from the pointer-to-member function
6583 pfn_from_ptrmemfunc (tree t)
6585 if (TREE_CODE (t) == PTRMEM_CST)
6590 expand_ptrmemfunc_cst (t, &delta, &pfn);
6595 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6598 /* Return an expression for DELTA from the pointer-to-member function
6602 delta_from_ptrmemfunc (tree t)
6604 if (TREE_CODE (t) == PTRMEM_CST)
6609 expand_ptrmemfunc_cst (t, &delta, &pfn);
6614 return build_ptrmemfunc_access_expr (t, delta_identifier);
6617 /* Convert value RHS to type TYPE as preparation for an assignment to
6618 an lvalue of type TYPE. ERRTYPE is a string to use in error
6619 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6620 are doing the conversion in order to pass the PARMNUMth argument of
6624 convert_for_assignment (tree type, tree rhs,
6625 const char *errtype, tree fndecl, int parmnum,
6626 tsubst_flags_t complain, int flags)
6629 enum tree_code coder;
6631 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6632 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6633 rhs = TREE_OPERAND (rhs, 0);
6635 rhstype = TREE_TYPE (rhs);
6636 coder = TREE_CODE (rhstype);
6638 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6639 && vector_types_convertible_p (type, rhstype, true))
6640 return convert (type, rhs);
6642 if (rhs == error_mark_node || rhstype == error_mark_node)
6643 return error_mark_node;
6644 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6645 return error_mark_node;
6647 /* The RHS of an assignment cannot have void type. */
6648 if (coder == VOID_TYPE)
6650 if (complain & tf_error)
6651 error ("void value not ignored as it ought to be");
6652 return error_mark_node;
6655 /* Simplify the RHS if possible. */
6656 if (TREE_CODE (rhs) == CONST_DECL)
6657 rhs = DECL_INITIAL (rhs);
6659 if (c_dialect_objc ())
6662 tree rname = fndecl;
6664 if (!strcmp (errtype, "assignment"))
6666 else if (!strcmp (errtype, "initialization"))
6670 tree selector = objc_message_selector ();
6674 if (selector && parmno > 1)
6681 if (objc_compare_types (type, rhstype, parmno, rname))
6682 return convert (type, rhs);
6687 The expression is implicitly converted (clause _conv_) to the
6688 cv-unqualified type of the left operand.
6690 We allow bad conversions here because by the time we get to this point
6691 we are committed to doing the conversion. If we end up doing a bad
6692 conversion, convert_like will complain. */
6693 if (!can_convert_arg_bad (type, rhstype, rhs))
6695 /* When -Wno-pmf-conversions is use, we just silently allow
6696 conversions from pointers-to-members to plain pointers. If
6697 the conversion doesn't work, cp_convert will complain. */
6699 && TYPE_PTR_P (type)
6700 && TYPE_PTRMEMFUNC_P (rhstype))
6701 rhs = cp_convert (strip_top_quals (type), rhs);
6704 if (complain & tf_error)
6706 /* If the right-hand side has unknown type, then it is an
6707 overloaded function. Call instantiate_type to get error
6709 if (rhstype == unknown_type_node)
6710 instantiate_type (type, rhs, tf_warning_or_error);
6712 error ("cannot convert %qT to %qT for argument %qP to %qD",
6713 rhstype, type, parmnum, fndecl);
6715 error ("cannot convert %qT to %qT in %s", rhstype, type,
6718 return error_mark_node;
6721 if (warn_missing_format_attribute)
6723 const enum tree_code codel = TREE_CODE (type);
6724 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6726 && check_missing_format_attribute (type, rhstype)
6727 && (complain & tf_warning))
6728 warning (OPT_Wmissing_format_attribute,
6729 "%s might be a candidate for a format attribute",
6733 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6735 if (warn_parentheses
6736 && type == boolean_type_node
6737 && TREE_CODE (rhs) == MODIFY_EXPR
6738 && !TREE_NO_WARNING (rhs)
6739 && TREE_TYPE (rhs) != boolean_type_node
6740 && (complain & tf_warning))
6742 warning (OPT_Wparentheses,
6743 "suggest parentheses around assignment used as truth value");
6744 TREE_NO_WARNING (rhs) = 1;
6747 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
6751 /* Convert RHS to be of type TYPE.
6752 If EXP is nonzero, it is the target of the initialization.
6753 ERRTYPE is a string to use in error messages.
6755 Two major differences between the behavior of
6756 `convert_for_assignment' and `convert_for_initialization'
6757 are that references are bashed in the former, while
6758 copied in the latter, and aggregates are assigned in
6759 the former (operator=) while initialized in the
6762 If using constructor make sure no conversion operator exists, if one does
6763 exist, an ambiguity exists.
6765 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6768 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6769 const char *errtype, tree fndecl, int parmnum,
6770 tsubst_flags_t complain)
6772 enum tree_code codel = TREE_CODE (type);
6774 enum tree_code coder;
6776 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6777 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6778 if (TREE_CODE (rhs) == NOP_EXPR
6779 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6780 && codel != REFERENCE_TYPE)
6781 rhs = TREE_OPERAND (rhs, 0);
6783 if (type == error_mark_node
6784 || rhs == error_mark_node
6785 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6786 return error_mark_node;
6788 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6789 && TREE_CODE (type) != ARRAY_TYPE
6790 && (TREE_CODE (type) != REFERENCE_TYPE
6791 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6792 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6793 && (TREE_CODE (type) != REFERENCE_TYPE
6794 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6795 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6796 rhs = decay_conversion (rhs);
6798 rhstype = TREE_TYPE (rhs);
6799 coder = TREE_CODE (rhstype);
6801 if (coder == ERROR_MARK)
6802 return error_mark_node;
6804 /* We accept references to incomplete types, so we can
6805 return here before checking if RHS is of complete type. */
6807 if (codel == REFERENCE_TYPE)
6809 /* This should eventually happen in convert_arguments. */
6810 int savew = 0, savee = 0;
6813 savew = warningcount, savee = errorcount;
6814 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6818 if (warningcount > savew)
6819 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6820 else if (errorcount > savee)
6821 error ("in passing argument %P of %q+D", parmnum, fndecl);
6827 exp = require_complete_type (exp);
6828 if (exp == error_mark_node)
6829 return error_mark_node;
6831 rhstype = non_reference (rhstype);
6833 type = complete_type (type);
6835 if (MAYBE_CLASS_TYPE_P (type))
6836 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6838 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6842 /* If RETVAL is the address of, or a reference to, a local variable or
6843 temporary give an appropriate warning. */
6846 maybe_warn_about_returning_address_of_local (tree retval)
6848 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6849 tree whats_returned = retval;
6853 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6854 whats_returned = TREE_OPERAND (whats_returned, 1);
6855 else if (CONVERT_EXPR_P (whats_returned)
6856 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6857 whats_returned = TREE_OPERAND (whats_returned, 0);
6862 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6864 whats_returned = TREE_OPERAND (whats_returned, 0);
6866 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6868 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6869 || TREE_CODE (whats_returned) == TARGET_EXPR)
6871 warning (0, "returning reference to temporary");
6874 if (TREE_CODE (whats_returned) == VAR_DECL
6875 && DECL_NAME (whats_returned)
6876 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6878 warning (0, "reference to non-lvalue returned");
6883 while (TREE_CODE (whats_returned) == COMPONENT_REF
6884 || TREE_CODE (whats_returned) == ARRAY_REF)
6885 whats_returned = TREE_OPERAND (whats_returned, 0);
6887 if (DECL_P (whats_returned)
6888 && DECL_NAME (whats_returned)
6889 && DECL_FUNCTION_SCOPE_P (whats_returned)
6890 && !(TREE_STATIC (whats_returned)
6891 || TREE_PUBLIC (whats_returned)))
6893 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6894 warning (0, "reference to local variable %q+D returned",
6897 warning (0, "address of local variable %q+D returned",
6903 /* Check that returning RETVAL from the current function is valid.
6904 Return an expression explicitly showing all conversions required to
6905 change RETVAL into the function return type, and to assign it to
6906 the DECL_RESULT for the function. Set *NO_WARNING to true if
6907 code reaches end of non-void function warning shouldn't be issued
6908 on this RETURN_EXPR. */
6911 check_return_expr (tree retval, bool *no_warning)
6914 /* The type actually returned by the function, after any
6917 int fn_returns_value_p;
6918 bool named_return_value_okay_p;
6920 *no_warning = false;
6922 /* A `volatile' function is one that isn't supposed to return, ever.
6923 (This is a G++ extension, used to get better code for functions
6924 that call the `volatile' function.) */
6925 if (TREE_THIS_VOLATILE (current_function_decl))
6926 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6928 /* Check for various simple errors. */
6929 if (DECL_DESTRUCTOR_P (current_function_decl))
6932 error ("returning a value from a destructor");
6935 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6937 if (in_function_try_handler)
6938 /* If a return statement appears in a handler of the
6939 function-try-block of a constructor, the program is ill-formed. */
6940 error ("cannot return from a handler of a function-try-block of a constructor");
6942 /* You can't return a value from a constructor. */
6943 error ("returning a value from a constructor");
6947 if (processing_template_decl)
6949 current_function_returns_value = 1;
6950 if (check_for_bare_parameter_packs (retval))
6951 retval = error_mark_node;
6955 /* When no explicit return-value is given in a function with a named
6956 return value, the named return value is used. */
6957 result = DECL_RESULT (current_function_decl);
6958 valtype = TREE_TYPE (result);
6959 gcc_assert (valtype != NULL_TREE);
6960 fn_returns_value_p = !VOID_TYPE_P (valtype);
6961 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6964 /* Check for a return statement with no return value in a function
6965 that's supposed to return a value. */
6966 if (!retval && fn_returns_value_p)
6968 permerror (input_location, "return-statement with no value, in function returning %qT",
6970 /* Clear this, so finish_function won't say that we reach the
6971 end of a non-void function (which we don't, we gave a
6973 current_function_returns_null = 0;
6974 /* And signal caller that TREE_NO_WARNING should be set on the
6975 RETURN_EXPR to avoid control reaches end of non-void function
6976 warnings in tree-cfg.c. */
6979 /* Check for a return statement with a value in a function that
6980 isn't supposed to return a value. */
6981 else if (retval && !fn_returns_value_p)
6983 if (VOID_TYPE_P (TREE_TYPE (retval)))
6984 /* You can return a `void' value from a function of `void'
6985 type. In that case, we have to evaluate the expression for
6986 its side-effects. */
6987 finish_expr_stmt (retval);
6989 permerror (input_location, "return-statement with a value, in function "
6990 "returning 'void'");
6991 current_function_returns_null = 1;
6993 /* There's really no value to return, after all. */
6997 /* Remember that this function can sometimes return without a
6999 current_function_returns_null = 1;
7001 /* Remember that this function did return a value. */
7002 current_function_returns_value = 1;
7004 /* Check for erroneous operands -- but after giving ourselves a
7005 chance to provide an error about returning a value from a void
7007 if (error_operand_p (retval))
7009 current_function_return_value = error_mark_node;
7010 return error_mark_node;
7013 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7014 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7015 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7016 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7018 && retval && null_ptr_cst_p (retval))
7019 warning (0, "%<operator new%> must not return NULL unless it is "
7020 "declared %<throw()%> (or -fcheck-new is in effect)");
7022 /* Effective C++ rule 15. See also start_function. */
7024 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7028 /* The function return type must be a reference to the current
7030 if (TREE_CODE (valtype) == REFERENCE_TYPE
7031 && same_type_ignoring_top_level_qualifiers_p
7032 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7034 /* Returning '*this' is obviously OK. */
7035 if (retval == current_class_ref)
7037 /* If we are calling a function whose return type is the same of
7038 the current class reference, it is ok. */
7039 else if (TREE_CODE (retval) == INDIRECT_REF
7040 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7045 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7048 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7050 [...] For a function with a class return type, if the expression
7051 in the return statement is the name of a local object, and the cv-
7052 unqualified type of the local object is the same as the function
7053 return type, an implementation is permitted to omit creating the tem-
7054 porary object to hold the function return value [...]
7056 So, if this is a value-returning function that always returns the same
7057 local variable, remember it.
7059 It might be nice to be more flexible, and choose the first suitable
7060 variable even if the function sometimes returns something else, but
7061 then we run the risk of clobbering the variable we chose if the other
7062 returned expression uses the chosen variable somehow. And people expect
7063 this restriction, anyway. (jason 2000-11-19)
7065 See finish_function and finalize_nrv for the rest of this optimization. */
7067 named_return_value_okay_p =
7068 (retval != NULL_TREE
7069 /* Must be a local, automatic variable. */
7070 && TREE_CODE (retval) == VAR_DECL
7071 && DECL_CONTEXT (retval) == current_function_decl
7072 && ! TREE_STATIC (retval)
7073 && ! DECL_ANON_UNION_VAR_P (retval)
7074 && (DECL_ALIGN (retval)
7075 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7076 /* The cv-unqualified type of the returned value must be the
7077 same as the cv-unqualified return type of the
7079 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7081 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7082 /* And the returned value must be non-volatile. */
7083 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7085 if (fn_returns_value_p && flag_elide_constructors)
7087 if (named_return_value_okay_p
7088 && (current_function_return_value == NULL_TREE
7089 || current_function_return_value == retval))
7090 current_function_return_value = retval;
7092 current_function_return_value = error_mark_node;
7095 /* We don't need to do any conversions when there's nothing being
7100 /* Do any required conversions. */
7101 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7102 /* No conversions are required. */
7106 /* The type the function is declared to return. */
7107 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7108 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7110 /* The functype's return type will have been set to void, if it
7111 was an incomplete type. Just treat this as 'return;' */
7112 if (VOID_TYPE_P (functype))
7113 return error_mark_node;
7115 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7116 treated as an rvalue for the purposes of overload resolution to
7117 favor move constructors over copy constructors. */
7118 if ((cxx_dialect != cxx98)
7119 && named_return_value_okay_p
7120 /* The variable must not have the `volatile' qualifier. */
7121 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7122 /* The return type must be a class type. */
7123 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7124 flags = flags | LOOKUP_PREFER_RVALUE;
7126 /* First convert the value to the function's return type, then
7127 to the type of return value's location to handle the
7128 case that functype is smaller than the valtype. */
7129 retval = convert_for_initialization
7130 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7131 tf_warning_or_error);
7132 retval = convert (valtype, retval);
7134 /* If the conversion failed, treat this just like `return;'. */
7135 if (retval == error_mark_node)
7137 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7138 else if (! cfun->returns_struct
7139 && TREE_CODE (retval) == TARGET_EXPR
7140 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7141 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7142 TREE_OPERAND (retval, 0));
7144 maybe_warn_about_returning_address_of_local (retval);
7147 /* Actually copy the value returned into the appropriate location. */
7148 if (retval && retval != result)
7149 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7155 /* Returns nonzero if the pointer-type FROM can be converted to the
7156 pointer-type TO via a qualification conversion. If CONSTP is -1,
7157 then we return nonzero if the pointers are similar, and the
7158 cv-qualification signature of FROM is a proper subset of that of TO.
7160 If CONSTP is positive, then all outer pointers have been
7164 comp_ptr_ttypes_real (tree to, tree from, int constp)
7166 bool to_more_cv_qualified = false;
7167 bool is_opaque_pointer = false;
7169 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7171 if (TREE_CODE (to) != TREE_CODE (from))
7174 if (TREE_CODE (from) == OFFSET_TYPE
7175 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7176 TYPE_OFFSET_BASETYPE (to)))
7179 /* Const and volatile mean something different for function types,
7180 so the usual checks are not appropriate. */
7181 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7183 /* In Objective-C++, some types may have been 'volatilized' by
7184 the compiler for EH; when comparing them here, the volatile
7185 qualification must be ignored. */
7186 bool objc_quals_match = objc_type_quals_match (to, from);
7188 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7191 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7195 to_more_cv_qualified = true;
7199 constp &= TYPE_READONLY (to);
7202 if (TREE_CODE (to) == VECTOR_TYPE)
7203 is_opaque_pointer = vector_targets_convertible_p (to, from);
7205 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7206 return ((constp >= 0 || to_more_cv_qualified)
7207 && (is_opaque_pointer
7208 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7212 /* When comparing, say, char ** to char const **, this function takes
7213 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7214 types to this function. */
7217 comp_ptr_ttypes (tree to, tree from)
7219 return comp_ptr_ttypes_real (to, from, 1);
7222 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7223 type or inheritance-related types, regardless of cv-quals. */
7226 ptr_reasonably_similar (const_tree to, const_tree from)
7228 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7230 /* Any target type is similar enough to void. */
7231 if (TREE_CODE (to) == VOID_TYPE
7232 || TREE_CODE (from) == VOID_TYPE)
7235 if (TREE_CODE (to) != TREE_CODE (from))
7238 if (TREE_CODE (from) == OFFSET_TYPE
7239 && comptypes (TYPE_OFFSET_BASETYPE (to),
7240 TYPE_OFFSET_BASETYPE (from),
7241 COMPARE_BASE | COMPARE_DERIVED))
7244 if (TREE_CODE (to) == VECTOR_TYPE
7245 && vector_types_convertible_p (to, from, false))
7248 if (TREE_CODE (to) == INTEGER_TYPE
7249 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7252 if (TREE_CODE (to) == FUNCTION_TYPE)
7255 if (TREE_CODE (to) != POINTER_TYPE)
7257 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7258 COMPARE_BASE | COMPARE_DERIVED);
7262 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7263 pointer-to-member types) are the same, ignoring cv-qualification at
7267 comp_ptr_ttypes_const (tree to, tree from)
7269 bool is_opaque_pointer = false;
7271 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7273 if (TREE_CODE (to) != TREE_CODE (from))
7276 if (TREE_CODE (from) == OFFSET_TYPE
7277 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7278 TYPE_OFFSET_BASETYPE (to)))
7281 if (TREE_CODE (to) == VECTOR_TYPE)
7282 is_opaque_pointer = vector_targets_convertible_p (to, from);
7284 if (TREE_CODE (to) != POINTER_TYPE)
7285 return (is_opaque_pointer
7286 || same_type_ignoring_top_level_qualifiers_p (to, from));
7290 /* Returns the type qualifiers for this type, including the qualifiers on the
7291 elements for an array type. */
7294 cp_type_quals (const_tree type)
7296 /* This CONST_CAST is okay because strip_array_types returns its
7297 argument unmodified and we assign it to a const_tree. */
7298 type = strip_array_types (CONST_CAST_TREE(type));
7299 if (type == error_mark_node)
7300 return TYPE_UNQUALIFIED;
7301 return TYPE_QUALS (type);
7304 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7308 cp_type_readonly (const_tree type)
7310 /* This CONST_CAST is okay because strip_array_types returns its
7311 argument unmodified and we assign it to a const_tree. */
7312 type = strip_array_types (CONST_CAST_TREE(type));
7313 return TYPE_READONLY (type);
7316 /* Returns nonzero if the TYPE contains a mutable member. */
7319 cp_has_mutable_p (const_tree type)
7321 /* This CONST_CAST is okay because strip_array_types returns its
7322 argument unmodified and we assign it to a const_tree. */
7323 type = strip_array_types (CONST_CAST_TREE(type));
7325 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7328 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7329 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7330 approximation. In particular, consider:
7333 struct S { int i; };
7334 const S s = { f(); }
7336 Here, we will make "s" as TREE_READONLY (because it is declared
7337 "const") -- only to reverse ourselves upon seeing that the
7338 initializer is non-constant. */
7341 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7343 tree type = TREE_TYPE (decl);
7345 if (type == error_mark_node)
7348 if (TREE_CODE (decl) == TYPE_DECL)
7351 if (TREE_CODE (type) == FUNCTION_TYPE
7352 && type_quals != TYPE_UNQUALIFIED)
7354 /* This was an error in C++98 (cv-qualifiers cannot be added to
7355 a function type), but DR 295 makes the code well-formed by
7356 dropping the extra qualifiers. */
7359 tree bad_type = build_qualified_type (type, type_quals);
7360 pedwarn (input_location, OPT_pedantic,
7361 "ignoring %qV qualifiers added to function type %qT",
7365 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7369 /* Avoid setting TREE_READONLY incorrectly. */
7370 if (/* If the object has a constructor, the constructor may modify
7372 TYPE_NEEDS_CONSTRUCTING (type)
7373 /* If the type isn't complete, we don't know yet if it will need
7375 || !COMPLETE_TYPE_P (type)
7376 /* If the type has a mutable component, that component might be
7378 || TYPE_HAS_MUTABLE_P (type))
7379 type_quals &= ~TYPE_QUAL_CONST;
7381 c_apply_type_quals_to_decl (type_quals, decl);
7384 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7385 exemplar types such that casting T1 to T2 is casting away constness
7386 if and only if there is no implicit conversion from T1 to T2. */
7389 casts_away_constness_r (tree *t1, tree *t2)
7394 /* [expr.const.cast]
7396 For multi-level pointer to members and multi-level mixed pointers
7397 and pointers to members (conv.qual), the "member" aspect of a
7398 pointer to member level is ignored when determining if a const
7399 cv-qualifier has been cast away. */
7400 /* [expr.const.cast]
7402 For two pointer types:
7404 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7405 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7408 casting from X1 to X2 casts away constness if, for a non-pointer
7409 type T there does not exist an implicit conversion (clause
7412 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7416 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7417 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7418 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7420 *t1 = cp_build_qualified_type (void_type_node,
7421 cp_type_quals (*t1));
7422 *t2 = cp_build_qualified_type (void_type_node,
7423 cp_type_quals (*t2));
7427 quals1 = cp_type_quals (*t1);
7428 quals2 = cp_type_quals (*t2);
7430 if (TYPE_PTRMEM_P (*t1))
7431 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7433 *t1 = TREE_TYPE (*t1);
7434 if (TYPE_PTRMEM_P (*t2))
7435 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7437 *t2 = TREE_TYPE (*t2);
7439 casts_away_constness_r (t1, t2);
7440 *t1 = build_pointer_type (*t1);
7441 *t2 = build_pointer_type (*t2);
7442 *t1 = cp_build_qualified_type (*t1, quals1);
7443 *t2 = cp_build_qualified_type (*t2, quals2);
7446 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7449 ??? This function returns non-zero if casting away qualifiers not
7450 just const. We would like to return to the caller exactly which
7451 qualifiers are casted away to give more accurate diagnostics.
7455 casts_away_constness (tree t1, tree t2)
7457 if (TREE_CODE (t2) == REFERENCE_TYPE)
7459 /* [expr.const.cast]
7461 Casting from an lvalue of type T1 to an lvalue of type T2
7462 using a reference cast casts away constness if a cast from an
7463 rvalue of type "pointer to T1" to the type "pointer to T2"
7464 casts away constness. */
7465 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7466 return casts_away_constness (build_pointer_type (t1),
7467 build_pointer_type (TREE_TYPE (t2)));
7470 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7471 /* [expr.const.cast]
7473 Casting from an rvalue of type "pointer to data member of X
7474 of type T1" to the type "pointer to data member of Y of type
7475 T2" casts away constness if a cast from an rvalue of type
7476 "pointer to T1" to the type "pointer to T2" casts away
7478 return casts_away_constness
7479 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7480 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7482 /* Casting away constness is only something that makes sense for
7483 pointer or reference types. */
7484 if (TREE_CODE (t1) != POINTER_TYPE
7485 || TREE_CODE (t2) != POINTER_TYPE)
7488 /* Top-level qualifiers don't matter. */
7489 t1 = TYPE_MAIN_VARIANT (t1);
7490 t2 = TYPE_MAIN_VARIANT (t2);
7491 casts_away_constness_r (&t1, &t2);
7492 if (!can_convert (t2, t1))
7498 /* If T is a REFERENCE_TYPE return the type to which T refers.
7499 Otherwise, return T itself. */
7502 non_reference (tree t)
7504 if (TREE_CODE (t) == REFERENCE_TYPE)
7510 /* Return nonzero if REF is an lvalue valid for this language;
7511 otherwise, print an error message and return zero. USE says
7512 how the lvalue is being used and so selects the error message. */
7515 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
7517 int win = lvalue_p (ref);
7519 if (!win && (complain & tf_error))