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 (int, tree *, tree, tree, 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 (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 /* Perform the integral promotions first so that bitfield
1703 expressions (which may promote to "int", even if the bitfield is
1704 declared "unsigned") are promoted correctly. */
1705 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1706 exp = perform_integral_promotions (exp);
1707 /* Perform the other conversions. */
1708 exp = decay_conversion (exp);
1713 /* EXPR is an expression with an integral or enumeration type.
1714 Perform the integral promotions in [conv.prom], and return the
1718 perform_integral_promotions (tree expr)
1725 If the bitfield has an enumerated type, it is treated as any
1726 other value of that type for promotion purposes. */
1727 type = is_bitfield_expr_with_lowered_type (expr);
1728 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1729 type = TREE_TYPE (expr);
1730 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1731 promoted_type = type_promotes_to (type);
1732 if (type != promoted_type)
1733 expr = cp_convert (promoted_type, expr);
1737 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1738 decay_conversion to one. */
1741 string_conv_p (const_tree totype, const_tree exp, int warn)
1745 if (TREE_CODE (totype) != POINTER_TYPE)
1748 t = TREE_TYPE (totype);
1749 if (!same_type_p (t, char_type_node)
1750 && !same_type_p (t, char16_type_node)
1751 && !same_type_p (t, char32_type_node)
1752 && !same_type_p (t, wchar_type_node))
1755 if (TREE_CODE (exp) == STRING_CST)
1757 /* Make sure that we don't try to convert between char and wide chars. */
1758 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1763 /* Is this a string constant which has decayed to 'const char *'? */
1764 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1765 if (!same_type_p (TREE_TYPE (exp), t))
1768 if (TREE_CODE (exp) != ADDR_EXPR
1769 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1773 /* This warning is not very useful, as it complains about printf. */
1775 warning (OPT_Wwrite_strings,
1776 "deprecated conversion from string constant to %qT",
1782 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1783 can, for example, use as an lvalue. This code used to be in
1784 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1785 expressions, where we're dealing with aggregates. But now it's again only
1786 called from unary_complex_lvalue. The case (in particular) that led to
1787 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1791 rationalize_conditional_expr (enum tree_code code, tree t,
1792 tsubst_flags_t complain)
1794 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1795 the first operand is always the one to be used if both operands
1796 are equal, so we know what conditional expression this used to be. */
1797 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1799 tree op0 = TREE_OPERAND (t, 0);
1800 tree op1 = TREE_OPERAND (t, 1);
1802 /* The following code is incorrect if either operand side-effects. */
1803 gcc_assert (!TREE_SIDE_EFFECTS (op0)
1804 && !TREE_SIDE_EFFECTS (op1));
1806 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1807 ? LE_EXPR : GE_EXPR),
1808 op0, TREE_CODE (op0),
1809 op1, TREE_CODE (op1),
1810 /*overloaded_p=*/NULL,
1812 cp_build_unary_op (code, op0, 0, complain),
1813 cp_build_unary_op (code, op1, 0, complain),
1818 build_conditional_expr (TREE_OPERAND (t, 0),
1819 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
1821 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
1826 /* Given the TYPE of an anonymous union field inside T, return the
1827 FIELD_DECL for the field. If not found return NULL_TREE. Because
1828 anonymous unions can nest, we must also search all anonymous unions
1829 that are directly reachable. */
1832 lookup_anon_field (tree t, tree type)
1836 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1838 if (TREE_STATIC (field))
1840 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1843 /* If we find it directly, return the field. */
1844 if (DECL_NAME (field) == NULL_TREE
1845 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1850 /* Otherwise, it could be nested, search harder. */
1851 if (DECL_NAME (field) == NULL_TREE
1852 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1854 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1862 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1863 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1864 non-NULL, it indicates the path to the base used to name MEMBER.
1865 If PRESERVE_REFERENCE is true, the expression returned will have
1866 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1867 returned will have the type referred to by the reference.
1869 This function does not perform access control; that is either done
1870 earlier by the parser when the name of MEMBER is resolved to MEMBER
1871 itself, or later when overload resolution selects one of the
1872 functions indicated by MEMBER. */
1875 build_class_member_access_expr (tree object, tree member,
1876 tree access_path, bool preserve_reference,
1877 tsubst_flags_t complain)
1881 tree result = NULL_TREE;
1883 if (error_operand_p (object) || error_operand_p (member))
1884 return error_mark_node;
1886 gcc_assert (DECL_P (member) || BASELINK_P (member));
1890 The type of the first expression shall be "class object" (of a
1892 object_type = TREE_TYPE (object);
1893 if (!currently_open_class (object_type)
1894 && !complete_type_or_else (object_type, object))
1895 return error_mark_node;
1896 if (!CLASS_TYPE_P (object_type))
1898 if (complain & tf_error)
1899 error ("request for member %qD in %qE, which is of non-class type %qT",
1900 member, object, object_type);
1901 return error_mark_node;
1904 /* The standard does not seem to actually say that MEMBER must be a
1905 member of OBJECT_TYPE. However, that is clearly what is
1907 if (DECL_P (member))
1909 member_scope = DECL_CLASS_CONTEXT (member);
1911 if (TREE_DEPRECATED (member))
1912 warn_deprecated_use (member);
1915 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
1916 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1917 presently be the anonymous union. Go outwards until we find a
1918 type related to OBJECT_TYPE. */
1919 while (ANON_AGGR_TYPE_P (member_scope)
1920 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1922 member_scope = TYPE_CONTEXT (member_scope);
1923 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1925 if (complain & tf_error)
1927 if (TREE_CODE (member) == FIELD_DECL)
1928 error ("invalid use of nonstatic data member %qE", member);
1930 error ("%qD is not a member of %qT", member, object_type);
1932 return error_mark_node;
1935 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1936 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1937 in the front end; only _DECLs and _REFs are lvalues in the back end. */
1939 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1941 object = cp_build_indirect_ref (temp, NULL, complain);
1944 /* In [expr.ref], there is an explicit list of the valid choices for
1945 MEMBER. We check for each of those cases here. */
1946 if (TREE_CODE (member) == VAR_DECL)
1948 /* A static data member. */
1950 /* If OBJECT has side-effects, they are supposed to occur. */
1951 if (TREE_SIDE_EFFECTS (object))
1952 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1954 else if (TREE_CODE (member) == FIELD_DECL)
1956 /* A non-static data member. */
1961 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1962 && integer_zerop (TREE_OPERAND (object, 0)));
1964 /* Convert OBJECT to the type of MEMBER. */
1965 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1966 TYPE_MAIN_VARIANT (member_scope)))
1971 binfo = lookup_base (access_path ? access_path : object_type,
1972 member_scope, ba_unique, &kind);
1973 if (binfo == error_mark_node)
1974 return error_mark_node;
1976 /* It is invalid to try to get to a virtual base of a
1977 NULL object. The most common cause is invalid use of
1979 if (null_object_p && kind == bk_via_virtual)
1981 if (complain & tf_error)
1983 error ("invalid access to non-static data member %qD of "
1986 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1988 return error_mark_node;
1991 /* Convert to the base. */
1992 object = build_base_path (PLUS_EXPR, object, binfo,
1994 /* If we found the base successfully then we should be able
1995 to convert to it successfully. */
1996 gcc_assert (object != error_mark_node);
1999 /* Complain about other invalid uses of offsetof, even though they will
2000 give the right answer. Note that we complain whether or not they
2001 actually used the offsetof macro, since there's no way to know at this
2002 point. So we just give a warning, instead of a pedwarn. */
2003 /* Do not produce this warning for base class field references, because
2004 we know for a fact that didn't come from offsetof. This does occur
2005 in various testsuite cases where a null object is passed where a
2006 vtable access is required. */
2007 if (null_object_p && warn_invalid_offsetof
2008 && CLASSTYPE_NON_POD_P (object_type)
2009 && !DECL_FIELD_IS_BASE (member)
2011 && (complain & tf_warning))
2013 warning (OPT_Winvalid_offsetof,
2014 "invalid access to non-static data member %qD "
2015 " of NULL object", member);
2016 warning (OPT_Winvalid_offsetof,
2017 "(perhaps the %<offsetof%> macro was used incorrectly)");
2020 /* If MEMBER is from an anonymous aggregate, we have converted
2021 OBJECT so that it refers to the class containing the
2022 anonymous union. Generate a reference to the anonymous union
2023 itself, and recur to find MEMBER. */
2024 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2025 /* When this code is called from build_field_call, the
2026 object already has the type of the anonymous union.
2027 That is because the COMPONENT_REF was already
2028 constructed, and was then disassembled before calling
2029 build_field_call. After the function-call code is
2030 cleaned up, this waste can be eliminated. */
2031 && (!same_type_ignoring_top_level_qualifiers_p
2032 (TREE_TYPE (object), DECL_CONTEXT (member))))
2034 tree anonymous_union;
2036 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2037 DECL_CONTEXT (member));
2038 object = build_class_member_access_expr (object,
2040 /*access_path=*/NULL_TREE,
2045 /* Compute the type of the field, as described in [expr.ref]. */
2046 type_quals = TYPE_UNQUALIFIED;
2047 member_type = TREE_TYPE (member);
2048 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2050 type_quals = (cp_type_quals (member_type)
2051 | cp_type_quals (object_type));
2053 /* A field is const (volatile) if the enclosing object, or the
2054 field itself, is const (volatile). But, a mutable field is
2055 not const, even within a const object. */
2056 if (DECL_MUTABLE_P (member))
2057 type_quals &= ~TYPE_QUAL_CONST;
2058 member_type = cp_build_qualified_type (member_type, type_quals);
2061 result = build3 (COMPONENT_REF, member_type, object, member,
2063 result = fold_if_not_in_template (result);
2065 /* Mark the expression const or volatile, as appropriate. Even
2066 though we've dealt with the type above, we still have to mark the
2067 expression itself. */
2068 if (type_quals & TYPE_QUAL_CONST)
2069 TREE_READONLY (result) = 1;
2070 if (type_quals & TYPE_QUAL_VOLATILE)
2071 TREE_THIS_VOLATILE (result) = 1;
2073 else if (BASELINK_P (member))
2075 /* The member is a (possibly overloaded) member function. */
2079 /* If the MEMBER is exactly one static member function, then we
2080 know the type of the expression. Otherwise, we must wait
2081 until overload resolution has been performed. */
2082 functions = BASELINK_FUNCTIONS (member);
2083 if (TREE_CODE (functions) == FUNCTION_DECL
2084 && DECL_STATIC_FUNCTION_P (functions))
2085 type = TREE_TYPE (functions);
2087 type = unknown_type_node;
2088 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2089 base. That will happen when the function is called. */
2090 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2092 else if (TREE_CODE (member) == CONST_DECL)
2094 /* The member is an enumerator. */
2096 /* If OBJECT has side-effects, they are supposed to occur. */
2097 if (TREE_SIDE_EFFECTS (object))
2098 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2103 if (complain & tf_error)
2104 error ("invalid use of %qD", member);
2105 return error_mark_node;
2108 if (!preserve_reference)
2111 If E2 is declared to have type "reference to T", then ... the
2112 type of E1.E2 is T. */
2113 result = convert_from_reference (result);
2118 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2119 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2122 lookup_destructor (tree object, tree scope, tree dtor_name)
2124 tree object_type = TREE_TYPE (object);
2125 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2128 if (scope && !check_dtor_name (scope, dtor_type))
2130 error ("qualified type %qT does not match destructor name ~%qT",
2132 return error_mark_node;
2134 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2136 /* In a template, names we can't find a match for are still accepted
2137 destructor names, and we check them here. */
2138 if (check_dtor_name (object_type, dtor_type))
2139 dtor_type = object_type;
2142 error ("object type %qT does not match destructor name ~%qT",
2143 object_type, dtor_type);
2144 return error_mark_node;
2148 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2150 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2151 TYPE_MAIN_VARIANT (object_type), dtor_type);
2152 return error_mark_node;
2154 expr = lookup_member (dtor_type, complete_dtor_identifier,
2155 /*protect=*/1, /*want_type=*/false);
2156 expr = (adjust_result_of_qualified_name_lookup
2157 (expr, dtor_type, object_type));
2161 /* An expression of the form "A::template B" has been resolved to
2162 DECL. Issue a diagnostic if B is not a template or template
2166 check_template_keyword (tree decl)
2168 /* The standard says:
2172 If a name prefixed by the keyword template is not a member
2173 template, the program is ill-formed.
2175 DR 228 removed the restriction that the template be a member
2178 DR 96, if accepted would add the further restriction that explicit
2179 template arguments must be provided if the template keyword is
2180 used, but, as of 2005-10-16, that DR is still in "drafting". If
2181 this DR is accepted, then the semantic checks here can be
2182 simplified, as the entity named must in fact be a template
2183 specialization, rather than, as at present, a set of overloaded
2184 functions containing at least one template function. */
2185 if (TREE_CODE (decl) != TEMPLATE_DECL
2186 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2188 if (!is_overloaded_fn (decl))
2189 permerror (input_location, "%qD is not a template", decl);
2194 if (BASELINK_P (fns))
2195 fns = BASELINK_FUNCTIONS (fns);
2198 tree fn = OVL_CURRENT (fns);
2199 if (TREE_CODE (fn) == TEMPLATE_DECL
2200 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2202 if (TREE_CODE (fn) == FUNCTION_DECL
2203 && DECL_USE_TEMPLATE (fn)
2204 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2206 fns = OVL_NEXT (fns);
2209 permerror (input_location, "%qD is not a template", decl);
2214 /* This function is called by the parser to process a class member
2215 access expression of the form OBJECT.NAME. NAME is a node used by
2216 the parser to represent a name; it is not yet a DECL. It may,
2217 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2218 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2219 there is no reason to do the lookup twice, so the parser keeps the
2220 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2221 be a template via the use of the "A::template B" syntax. */
2224 finish_class_member_access_expr (tree object, tree name, bool template_p,
2225 tsubst_flags_t complain)
2230 tree access_path = NULL_TREE;
2231 tree orig_object = object;
2232 tree orig_name = name;
2234 if (object == error_mark_node || name == error_mark_node)
2235 return error_mark_node;
2237 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2238 if (!objc_is_public (object, name))
2239 return error_mark_node;
2241 object_type = TREE_TYPE (object);
2243 if (processing_template_decl)
2245 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2246 dependent_type_p (object_type)
2247 /* If NAME is just an IDENTIFIER_NODE, then the expression
2249 || TREE_CODE (object) == IDENTIFIER_NODE
2250 /* If NAME is "f<args>", where either 'f' or 'args' is
2251 dependent, then the expression is dependent. */
2252 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2253 && dependent_template_id_p (TREE_OPERAND (name, 0),
2254 TREE_OPERAND (name, 1)))
2255 /* If NAME is "T::X" where "T" is dependent, then the
2256 expression is dependent. */
2257 || (TREE_CODE (name) == SCOPE_REF
2258 && TYPE_P (TREE_OPERAND (name, 0))
2259 && dependent_type_p (TREE_OPERAND (name, 0))))
2260 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2261 object = build_non_dependent_expr (object);
2266 The type of the first expression shall be "class object" (of a
2268 if (!currently_open_class (object_type)
2269 && !complete_type_or_else (object_type, object))
2270 return error_mark_node;
2271 if (!CLASS_TYPE_P (object_type))
2273 if (complain & tf_error)
2274 error ("request for member %qD in %qE, which is of non-class type %qT",
2275 name, object, object_type);
2276 return error_mark_node;
2279 if (BASELINK_P (name))
2280 /* A member function that has already been looked up. */
2284 bool is_template_id = false;
2285 tree template_args = NULL_TREE;
2288 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2290 is_template_id = true;
2291 template_args = TREE_OPERAND (name, 1);
2292 name = TREE_OPERAND (name, 0);
2294 if (TREE_CODE (name) == OVERLOAD)
2295 name = DECL_NAME (get_first_fn (name));
2296 else if (DECL_P (name))
2297 name = DECL_NAME (name);
2300 if (TREE_CODE (name) == SCOPE_REF)
2302 /* A qualified name. The qualifying class or namespace `S'
2303 has already been looked up; it is either a TYPE or a
2305 scope = TREE_OPERAND (name, 0);
2306 name = TREE_OPERAND (name, 1);
2308 /* If SCOPE is a namespace, then the qualified name does not
2309 name a member of OBJECT_TYPE. */
2310 if (TREE_CODE (scope) == NAMESPACE_DECL)
2312 if (complain & tf_error)
2313 error ("%<%D::%D%> is not a member of %qT",
2314 scope, name, object_type);
2315 return error_mark_node;
2318 gcc_assert (CLASS_TYPE_P (scope));
2319 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2320 || TREE_CODE (name) == BIT_NOT_EXPR);
2322 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2323 access_path = lookup_base (object_type, scope, ba_check, NULL);
2324 if (access_path == error_mark_node)
2325 return error_mark_node;
2328 if (complain & tf_error)
2329 error ("%qT is not a base of %qT", scope, object_type);
2330 return error_mark_node;
2336 access_path = object_type;
2339 if (TREE_CODE (name) == BIT_NOT_EXPR)
2340 member = lookup_destructor (object, scope, name);
2343 /* Look up the member. */
2344 member = lookup_member (access_path, name, /*protect=*/1,
2345 /*want_type=*/false);
2346 if (member == NULL_TREE)
2348 if (complain & tf_error)
2349 error ("%qD has no member named %qE", object_type, name);
2350 return error_mark_node;
2352 if (member == error_mark_node)
2353 return error_mark_node;
2358 tree templ = member;
2360 if (BASELINK_P (templ))
2361 templ = lookup_template_function (templ, template_args);
2364 if (complain & tf_error)
2365 error ("%qD is not a member template function", name);
2366 return error_mark_node;
2371 if (TREE_DEPRECATED (member))
2372 warn_deprecated_use (member);
2375 check_template_keyword (member);
2377 expr = build_class_member_access_expr (object, member, access_path,
2378 /*preserve_reference=*/false,
2380 if (processing_template_decl && expr != error_mark_node)
2382 if (BASELINK_P (member))
2384 if (TREE_CODE (orig_name) == SCOPE_REF)
2385 BASELINK_QUALIFIED_P (member) = 1;
2388 return build_min_non_dep (COMPONENT_REF, expr,
2389 orig_object, orig_name,
2396 /* Return an expression for the MEMBER_NAME field in the internal
2397 representation of PTRMEM, a pointer-to-member function. (Each
2398 pointer-to-member function type gets its own RECORD_TYPE so it is
2399 more convenient to access the fields by name than by FIELD_DECL.)
2400 This routine converts the NAME to a FIELD_DECL and then creates the
2401 node for the complete expression. */
2404 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2410 /* This code is a stripped down version of
2411 build_class_member_access_expr. It does not work to use that
2412 routine directly because it expects the object to be of class
2414 ptrmem_type = TREE_TYPE (ptrmem);
2415 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2416 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2417 /*want_type=*/false);
2418 member_type = cp_build_qualified_type (TREE_TYPE (member),
2419 cp_type_quals (ptrmem_type));
2420 return fold_build3 (COMPONENT_REF, member_type,
2421 ptrmem, member, NULL_TREE);
2424 /* Given an expression PTR for a pointer, return an expression
2425 for the value pointed to.
2426 ERRORSTRING is the name of the operator to appear in error messages.
2428 This function may need to overload OPERATOR_FNNAME.
2429 Must also handle REFERENCE_TYPEs for C++. */
2432 build_x_indirect_ref (tree expr, const char *errorstring,
2433 tsubst_flags_t complain)
2435 tree orig_expr = expr;
2438 if (processing_template_decl)
2440 if (type_dependent_expression_p (expr))
2441 return build_min_nt (INDIRECT_REF, expr);
2442 expr = build_non_dependent_expr (expr);
2445 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2446 NULL_TREE, /*overloaded_p=*/NULL, complain);
2448 rval = cp_build_indirect_ref (expr, errorstring, complain);
2450 if (processing_template_decl && rval != error_mark_node)
2451 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2456 /* Helper function called from c-common. */
2458 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2459 tree ptr, const char *errorstring)
2461 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2465 cp_build_indirect_ref (tree ptr, const char *errorstring,
2466 tsubst_flags_t complain)
2470 if (ptr == error_mark_node)
2471 return error_mark_node;
2473 if (ptr == current_class_ptr)
2474 return current_class_ref;
2476 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2477 ? ptr : decay_conversion (ptr));
2478 type = TREE_TYPE (pointer);
2480 if (POINTER_TYPE_P (type))
2484 If the type of the expression is "pointer to T," the type
2485 of the result is "T."
2487 We must use the canonical variant because certain parts of
2488 the back end, like fold, do pointer comparisons between
2490 tree t = canonical_type_variant (TREE_TYPE (type));
2492 if (CONVERT_EXPR_P (ptr)
2493 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2495 /* If a warning is issued, mark it to avoid duplicates from
2496 the backend. This only needs to be done at
2497 warn_strict_aliasing > 2. */
2498 if (warn_strict_aliasing > 2)
2499 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2500 type, TREE_OPERAND (ptr, 0)))
2501 TREE_NO_WARNING (ptr) = 1;
2504 if (VOID_TYPE_P (t))
2506 /* A pointer to incomplete type (other than cv void) can be
2507 dereferenced [expr.unary.op]/1 */
2508 if (complain & tf_error)
2509 error ("%qT is not a pointer-to-object type", type);
2510 return error_mark_node;
2512 else if (TREE_CODE (pointer) == ADDR_EXPR
2513 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2514 /* The POINTER was something like `&x'. We simplify `*&x' to
2516 return TREE_OPERAND (pointer, 0);
2519 tree ref = build1 (INDIRECT_REF, t, pointer);
2521 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2522 so that we get the proper error message if the result is used
2523 to assign to. Also, &* is supposed to be a no-op. */
2524 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2525 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2526 TREE_SIDE_EFFECTS (ref)
2527 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2531 else if (!(complain & tf_error))
2532 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2534 /* `pointer' won't be an error_mark_node if we were given a
2535 pointer to member, so it's cool to check for this here. */
2536 else if (TYPE_PTR_TO_MEMBER_P (type))
2537 error ("invalid use of %qs on pointer to member", errorstring);
2538 else if (pointer != error_mark_node)
2541 error ("invalid type argument of %qs", errorstring);
2543 error ("invalid type argument");
2545 return error_mark_node;
2548 /* This handles expressions of the form "a[i]", which denotes
2551 This is logically equivalent in C to *(a+i), but we may do it differently.
2552 If A is a variable or a member, we generate a primitive ARRAY_REF.
2553 This avoids forcing the array out of registers, and can work on
2554 arrays that are not lvalues (for example, members of structures returned
2557 If INDEX is of some user-defined type, it must be converted to
2558 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2559 will inherit the type of the array, which will be some pointer type.
2561 LOC is the location to use in building the array reference. */
2564 build_array_ref (tree array, tree idx, location_t loc)
2570 error_at (loc, "subscript missing in array reference");
2571 return error_mark_node;
2574 if (TREE_TYPE (array) == error_mark_node
2575 || TREE_TYPE (idx) == error_mark_node)
2576 return error_mark_node;
2578 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2580 switch (TREE_CODE (array))
2584 tree value = build_array_ref (TREE_OPERAND (array, 1), idx, loc);
2585 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2586 TREE_OPERAND (array, 0), value);
2587 SET_EXPR_LOCATION (ret, loc);
2592 ret = build_conditional_expr
2593 (TREE_OPERAND (array, 0),
2594 build_array_ref (TREE_OPERAND (array, 1), idx, loc),
2595 build_array_ref (TREE_OPERAND (array, 2), idx, loc),
2596 tf_warning_or_error);
2597 protected_set_expr_location (ret, loc);
2604 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2608 warn_array_subscript_with_type_char (idx);
2610 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2612 error_at (loc, "array subscript is not an integer");
2613 return error_mark_node;
2616 /* Apply integral promotions *after* noticing character types.
2617 (It is unclear why we do these promotions -- the standard
2618 does not say that we should. In fact, the natural thing would
2619 seem to be to convert IDX to ptrdiff_t; we're performing
2620 pointer arithmetic.) */
2621 idx = perform_integral_promotions (idx);
2623 /* An array that is indexed by a non-constant
2624 cannot be stored in a register; we must be able to do
2625 address arithmetic on its address.
2626 Likewise an array of elements of variable size. */
2627 if (TREE_CODE (idx) != INTEGER_CST
2628 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2629 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2632 if (!cxx_mark_addressable (array))
2633 return error_mark_node;
2636 /* An array that is indexed by a constant value which is not within
2637 the array bounds cannot be stored in a register either; because we
2638 would get a crash in store_bit_field/extract_bit_field when trying
2639 to access a non-existent part of the register. */
2640 if (TREE_CODE (idx) == INTEGER_CST
2641 && TYPE_DOMAIN (TREE_TYPE (array))
2642 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2644 if (!cxx_mark_addressable (array))
2645 return error_mark_node;
2648 if (!lvalue_p (array))
2649 pedwarn (loc, OPT_pedantic,
2650 "ISO C++ forbids subscripting non-lvalue array");
2652 /* Note in C++ it is valid to subscript a `register' array, since
2653 it is valid to take the address of something with that
2654 storage specification. */
2658 while (TREE_CODE (foo) == COMPONENT_REF)
2659 foo = TREE_OPERAND (foo, 0);
2660 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2661 warning_at (loc, OPT_Wextra,
2662 "subscripting array declared %<register%>");
2665 type = TREE_TYPE (TREE_TYPE (array));
2666 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2667 /* Array ref is const/volatile if the array elements are
2668 or if the array is.. */
2669 TREE_READONLY (rval)
2670 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2671 TREE_SIDE_EFFECTS (rval)
2672 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2673 TREE_THIS_VOLATILE (rval)
2674 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2675 ret = require_complete_type (fold_if_not_in_template (rval));
2676 protected_set_expr_location (ret, loc);
2681 tree ar = default_conversion (array);
2682 tree ind = default_conversion (idx);
2684 /* Put the integer in IND to simplify error checking. */
2685 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2692 if (ar == error_mark_node)
2695 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2697 error_at (loc, "subscripted value is neither array nor pointer");
2698 return error_mark_node;
2700 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2702 error_at (loc, "array subscript is not an integer");
2703 return error_mark_node;
2706 warn_array_subscript_with_type_char (idx);
2708 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2710 tf_warning_or_error),
2712 tf_warning_or_error);
2713 protected_set_expr_location (ret, loc);
2718 /* Resolve a pointer to member function. INSTANCE is the object
2719 instance to use, if the member points to a virtual member.
2721 This used to avoid checking for virtual functions if basetype
2722 has no virtual functions, according to an earlier ANSI draft.
2723 With the final ISO C++ rules, such an optimization is
2724 incorrect: A pointer to a derived member can be static_cast
2725 to pointer-to-base-member, as long as the dynamic object
2726 later has the right member. */
2729 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2731 if (TREE_CODE (function) == OFFSET_REF)
2732 function = TREE_OPERAND (function, 1);
2734 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2736 tree idx, delta, e1, e2, e3, vtbl, basetype;
2737 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2739 tree instance_ptr = *instance_ptrptr;
2740 tree instance_save_expr = 0;
2741 if (instance_ptr == error_mark_node)
2743 if (TREE_CODE (function) == PTRMEM_CST)
2745 /* Extracting the function address from a pmf is only
2746 allowed with -Wno-pmf-conversions. It only works for
2748 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2749 e1 = convert (fntype, e1);
2754 error ("object missing in use of %qE", function);
2755 return error_mark_node;
2759 if (TREE_SIDE_EFFECTS (instance_ptr))
2760 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2762 if (TREE_SIDE_EFFECTS (function))
2763 function = save_expr (function);
2765 /* Start by extracting all the information from the PMF itself. */
2766 e3 = pfn_from_ptrmemfunc (function);
2767 delta = delta_from_ptrmemfunc (function);
2768 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2769 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2771 case ptrmemfunc_vbit_in_pfn:
2772 e1 = cp_build_binary_op (input_location,
2773 BIT_AND_EXPR, idx, integer_one_node,
2774 tf_warning_or_error);
2775 idx = cp_build_binary_op (input_location,
2776 MINUS_EXPR, idx, integer_one_node,
2777 tf_warning_or_error);
2780 case ptrmemfunc_vbit_in_delta:
2781 e1 = cp_build_binary_op (input_location,
2782 BIT_AND_EXPR, delta, integer_one_node,
2783 tf_warning_or_error);
2784 delta = cp_build_binary_op (input_location,
2785 RSHIFT_EXPR, delta, integer_one_node,
2786 tf_warning_or_error);
2793 /* Convert down to the right base before using the instance. A
2794 special case is that in a pointer to member of class C, C may
2795 be incomplete. In that case, the function will of course be
2796 a member of C, and no conversion is required. In fact,
2797 lookup_base will fail in that case, because incomplete
2798 classes do not have BINFOs. */
2799 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2800 if (!same_type_ignoring_top_level_qualifiers_p
2801 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2803 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2804 basetype, ba_check, NULL);
2805 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2807 if (instance_ptr == error_mark_node)
2808 return error_mark_node;
2810 /* ...and then the delta in the PMF. */
2811 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2812 instance_ptr, fold_convert (sizetype, delta));
2814 /* Hand back the adjusted 'this' argument to our caller. */
2815 *instance_ptrptr = instance_ptr;
2817 /* Next extract the vtable pointer from the object. */
2818 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2820 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2821 /* If the object is not dynamic the access invokes undefined
2822 behavior. As it is not executed in this case silence the
2823 spurious warnings it may provoke. */
2824 TREE_NO_WARNING (vtbl) = 1;
2826 /* Finally, extract the function pointer from the vtable. */
2827 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2828 fold_convert (sizetype, idx));
2829 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2830 TREE_CONSTANT (e2) = 1;
2832 /* When using function descriptors, the address of the
2833 vtable entry is treated as a function pointer. */
2834 if (TARGET_VTABLE_USES_DESCRIPTORS)
2835 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2836 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2837 tf_warning_or_error));
2839 e2 = fold_convert (TREE_TYPE (e3), e2);
2840 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2842 /* Make sure this doesn't get evaluated first inside one of the
2843 branches of the COND_EXPR. */
2844 if (instance_save_expr)
2845 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2846 instance_save_expr, e1);
2853 /* Used by the C-common bits. */
2855 build_function_call (tree function, tree params)
2857 return cp_build_function_call (function, params, tf_warning_or_error);
2861 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2863 tree fntype, fndecl;
2864 tree name = NULL_TREE;
2866 tree original = function;
2867 int nargs, parm_types_len;
2871 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2872 expressions, like those used for ObjC messenger dispatches. */
2873 function = objc_rewrite_function_call (function, params);
2875 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2876 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2877 if (TREE_CODE (function) == NOP_EXPR
2878 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2879 function = TREE_OPERAND (function, 0);
2881 if (TREE_CODE (function) == FUNCTION_DECL)
2883 name = DECL_NAME (function);
2885 mark_used (function);
2888 /* Convert anything with function type to a pointer-to-function. */
2889 if (DECL_MAIN_P (function) && (complain & tf_error))
2890 pedwarn (input_location, OPT_pedantic,
2891 "ISO C++ forbids calling %<::main%> from within program");
2893 function = build_addr_func (function);
2899 function = build_addr_func (function);
2902 if (function == error_mark_node)
2903 return error_mark_node;
2905 fntype = TREE_TYPE (function);
2907 if (TYPE_PTRMEMFUNC_P (fntype))
2909 if (complain & tf_error)
2910 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2911 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2912 original, original);
2913 return error_mark_node;
2916 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2917 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2919 if (!((TREE_CODE (fntype) == POINTER_TYPE
2920 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2922 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2924 if (complain & tf_error)
2925 error ("%qE cannot be used as a function", original);
2926 return error_mark_node;
2929 /* fntype now gets the type of function pointed to. */
2930 fntype = TREE_TYPE (fntype);
2931 parm_types = TYPE_ARG_TYPES (fntype);
2933 /* Allocate storage for converted arguments. */
2934 parm_types_len = list_length (parm_types);
2935 nargs = list_length (params);
2936 if (parm_types_len > nargs)
2937 nargs = parm_types_len;
2938 argarray = (tree *) alloca (nargs * sizeof (tree));
2940 /* Convert the parameters to the types declared in the
2941 function prototype, or apply default promotions. */
2942 nargs = convert_arguments (nargs, argarray, parm_types,
2943 params, fndecl, LOOKUP_NORMAL,
2946 return error_mark_node;
2948 /* Check for errors in format strings and inappropriately
2950 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2953 return build_cxx_call (function, nargs, argarray);
2956 /* Convert the actual parameter expressions in the list VALUES
2957 to the types in the list TYPELIST.
2958 If parmdecls is exhausted, or when an element has NULL as its type,
2959 perform the default conversions.
2961 Store the converted arguments in ARGARRAY. NARGS is the size of this array.
2963 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2965 This is also where warnings about wrong number of args are generated.
2967 Returns the actual number of arguments processed (which might be less
2968 than NARGS), or -1 on error.
2970 VALUES is a chain of TREE_LIST nodes with the elements of the list
2971 in the TREE_VALUE slots of those nodes.
2973 In C++, unspecified trailing parameters can be filled in with their
2974 default arguments, if such were specified. Do so here. */
2977 convert_arguments (int nargs, tree *argarray,
2978 tree typelist, tree values, tree fndecl, int flags,
2979 tsubst_flags_t complain)
2981 tree typetail, valtail;
2982 const char *called_thing = 0;
2985 /* Argument passing is always copy-initialization. */
2986 flags |= LOOKUP_ONLYCONVERTING;
2990 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2992 if (DECL_NAME (fndecl) == NULL_TREE
2993 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2994 called_thing = "constructor";
2996 called_thing = "member function";
2999 called_thing = "function";
3002 for (valtail = values, typetail = typelist;
3004 valtail = TREE_CHAIN (valtail), i++)
3006 tree type = typetail ? TREE_VALUE (typetail) : 0;
3007 tree val = TREE_VALUE (valtail);
3009 if (val == error_mark_node || type == error_mark_node)
3012 if (type == void_type_node)
3014 if (complain & tf_error)
3018 error ("too many arguments to %s %q+#D",
3019 called_thing, fndecl);
3020 error ("at this point in file");
3023 error ("too many arguments to function");
3030 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3031 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3032 if (TREE_CODE (val) == NOP_EXPR
3033 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3034 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3035 val = TREE_OPERAND (val, 0);
3037 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3039 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3040 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3041 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3042 val = decay_conversion (val);
3045 if (val == error_mark_node)
3050 /* Formal parm type is specified by a function prototype. */
3053 if (!COMPLETE_TYPE_P (complete_type (type)))
3055 if (complain & tf_error)
3058 error ("parameter %P of %qD has incomplete type %qT",
3061 error ("parameter %P has incomplete type %qT", i, type);
3063 parmval = error_mark_node;
3067 parmval = convert_for_initialization
3068 (NULL_TREE, type, val, flags,
3069 "argument passing", fndecl, i, complain);
3070 parmval = convert_for_arg_passing (type, parmval);
3073 if (parmval == error_mark_node)
3076 argarray[i] = parmval;
3080 if (fndecl && DECL_BUILT_IN (fndecl)
3081 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3082 /* Don't do ellipsis conversion for __built_in_constant_p
3083 as this will result in spurious warnings for non-POD
3085 val = require_complete_type (val);
3087 val = convert_arg_to_ellipsis (val);
3093 typetail = TREE_CHAIN (typetail);
3096 if (typetail != 0 && typetail != void_list_node)
3098 /* See if there are default arguments that can be used. Because
3099 we hold default arguments in the FUNCTION_TYPE (which is so
3100 wrong), we can see default parameters here from deduced
3101 contexts (and via typeof) for indirect function calls.
3102 Fortunately we know whether we have a function decl to
3103 provide default arguments in a language conformant
3105 if (fndecl && TREE_PURPOSE (typetail)
3106 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3108 for (; typetail != void_list_node; ++i)
3111 = convert_default_arg (TREE_VALUE (typetail),
3112 TREE_PURPOSE (typetail),
3115 if (parmval == error_mark_node)
3118 argarray[i] = parmval;
3119 typetail = TREE_CHAIN (typetail);
3120 /* ends with `...'. */
3121 if (typetail == NULL_TREE)
3127 if (complain & tf_error)
3131 error ("too few arguments to %s %q+#D",
3132 called_thing, fndecl);
3133 error ("at this point in file");
3136 error ("too few arguments to function");
3142 gcc_assert (i <= nargs);
3146 /* Build a binary-operation expression, after performing default
3147 conversions on the operands. CODE is the kind of expression to
3148 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3149 are the tree codes which correspond to ARG1 and ARG2 when issuing
3150 warnings about possibly misplaced parentheses. They may differ
3151 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3152 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3153 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3154 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3155 ARG2_CODE as ERROR_MARK. */
3158 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3159 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3160 tsubst_flags_t complain)
3169 if (processing_template_decl)
3171 if (type_dependent_expression_p (arg1)
3172 || type_dependent_expression_p (arg2))
3173 return build_min_nt (code, arg1, arg2);
3174 arg1 = build_non_dependent_expr (arg1);
3175 arg2 = build_non_dependent_expr (arg2);
3178 if (code == DOTSTAR_EXPR)
3179 expr = build_m_component_ref (arg1, arg2);
3181 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3182 overloaded_p, complain);
3184 /* Check for cases such as x+y<<z which users are likely to
3185 misinterpret. But don't warn about obj << x + y, since that is a
3186 common idiom for I/O. */
3187 if (warn_parentheses
3188 && !processing_template_decl
3189 && !error_operand_p (arg1)
3190 && !error_operand_p (arg2)
3191 && (code != LSHIFT_EXPR
3192 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3193 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3195 if (processing_template_decl && expr != error_mark_node)
3196 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3201 /* Build and return an ARRAY_REF expression. */
3204 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3206 tree orig_arg1 = arg1;
3207 tree orig_arg2 = arg2;
3210 if (processing_template_decl)
3212 if (type_dependent_expression_p (arg1)
3213 || type_dependent_expression_p (arg2))
3214 return build_min_nt (ARRAY_REF, arg1, arg2,
3215 NULL_TREE, NULL_TREE);
3216 arg1 = build_non_dependent_expr (arg1);
3217 arg2 = build_non_dependent_expr (arg2);
3220 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3221 /*overloaded_p=*/NULL, complain);
3223 if (processing_template_decl && expr != error_mark_node)
3224 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3225 NULL_TREE, NULL_TREE);
3229 /* For the c-common bits. */
3231 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3232 int convert_p ATTRIBUTE_UNUSED)
3234 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3238 /* Build a binary-operation expression without default conversions.
3239 CODE is the kind of expression to build.
3240 LOCATION is the location_t of the operator in the source code.
3241 This function differs from `build' in several ways:
3242 the data type of the result is computed and recorded in it,
3243 warnings are generated if arg data types are invalid,
3244 special handling for addition and subtraction of pointers is known,
3245 and some optimization is done (operations on narrow ints
3246 are done in the narrower type when that gives the same result).
3247 Constant folding is also done before the result is returned.
3249 Note that the operands will never have enumeral types
3250 because either they have just had the default conversions performed
3251 or they have both just been converted to some other type in which
3252 the arithmetic is to be done.
3254 C++: must do special pointer arithmetic when implementing
3255 multiple inheritance, and deal with pointer to member functions. */
3258 cp_build_binary_op (location_t location,
3259 enum tree_code code, tree orig_op0, tree orig_op1,
3260 tsubst_flags_t complain)
3263 enum tree_code code0, code1;
3265 const char *invalid_op_diag;
3267 /* Expression code to give to the expression when it is built.
3268 Normally this is CODE, which is what the caller asked for,
3269 but in some special cases we change it. */
3270 enum tree_code resultcode = code;
3272 /* Data type in which the computation is to be performed.
3273 In the simplest cases this is the common type of the arguments. */
3274 tree result_type = NULL;
3276 /* Nonzero means operands have already been type-converted
3277 in whatever way is necessary.
3278 Zero means they need to be converted to RESULT_TYPE. */
3281 /* Nonzero means create the expression with this type, rather than
3283 tree build_type = 0;
3285 /* Nonzero means after finally constructing the expression
3286 convert it to this type. */
3287 tree final_type = 0;
3291 /* Nonzero if this is an operation like MIN or MAX which can
3292 safely be computed in short if both args are promoted shorts.
3293 Also implies COMMON.
3294 -1 indicates a bitwise operation; this makes a difference
3295 in the exact conditions for when it is safe to do the operation
3296 in a narrower mode. */
3299 /* Nonzero if this is a comparison operation;
3300 if both args are promoted shorts, compare the original shorts.
3301 Also implies COMMON. */
3302 int short_compare = 0;
3304 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3307 /* True if both operands have arithmetic type. */
3308 bool arithmetic_types_p;
3310 /* Apply default conversions. */
3314 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3315 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3316 || code == TRUTH_XOR_EXPR)
3318 if (!really_overloaded_fn (op0))
3319 op0 = decay_conversion (op0);
3320 if (!really_overloaded_fn (op1))
3321 op1 = decay_conversion (op1);
3325 if (!really_overloaded_fn (op0))
3326 op0 = default_conversion (op0);
3327 if (!really_overloaded_fn (op1))
3328 op1 = default_conversion (op1);
3331 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3332 STRIP_TYPE_NOPS (op0);
3333 STRIP_TYPE_NOPS (op1);
3335 /* DTRT if one side is an overloaded function, but complain about it. */
3336 if (type_unknown_p (op0))
3338 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3339 if (t != error_mark_node)
3341 if (complain & tf_error)
3342 permerror (input_location, "assuming cast to type %qT from overloaded function",
3347 if (type_unknown_p (op1))
3349 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3350 if (t != error_mark_node)
3352 if (complain & tf_error)
3353 permerror (input_location, "assuming cast to type %qT from overloaded function",
3359 type0 = TREE_TYPE (op0);
3360 type1 = TREE_TYPE (op1);
3362 /* The expression codes of the data types of the arguments tell us
3363 whether the arguments are integers, floating, pointers, etc. */
3364 code0 = TREE_CODE (type0);
3365 code1 = TREE_CODE (type1);
3367 /* If an error was already reported for one of the arguments,
3368 avoid reporting another error. */
3370 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3371 return error_mark_node;
3373 if ((invalid_op_diag
3374 = targetm.invalid_binary_op (code, type0, type1)))
3376 error (invalid_op_diag);
3377 return error_mark_node;
3383 /* Subtraction of two similar pointers.
3384 We must subtract them as integers, then divide by object size. */
3385 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3386 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3388 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3389 /* In all other cases except pointer - int, the usual arithmetic
3391 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3396 /* The pointer - int case is just like pointer + int; fall
3399 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3400 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3404 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3405 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3406 if (processing_template_decl)
3408 result_type = TREE_TYPE (ptr_operand);
3411 return cp_pointer_int_sum (code,
3422 case TRUNC_DIV_EXPR:
3424 case FLOOR_DIV_EXPR:
3425 case ROUND_DIV_EXPR:
3426 case EXACT_DIV_EXPR:
3427 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3428 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3429 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3430 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3432 enum tree_code tcode0 = code0, tcode1 = code1;
3434 warn_for_div_by_zero (location, op1);
3436 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3437 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3438 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3439 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3441 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3442 resultcode = RDIV_EXPR;
3444 /* When dividing two signed integers, we have to promote to int.
3445 unless we divide by a constant != -1. Note that default
3446 conversion will have been performed on the operands at this
3447 point, so we have to dig out the original type to find out if
3449 shorten = ((TREE_CODE (op0) == NOP_EXPR
3450 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3451 || (TREE_CODE (op1) == INTEGER_CST
3452 && ! integer_all_onesp (op1)));
3461 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3462 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3463 && !VECTOR_FLOAT_TYPE_P (type0)
3464 && !VECTOR_FLOAT_TYPE_P (type1)))
3468 case TRUNC_MOD_EXPR:
3469 case FLOOR_MOD_EXPR:
3470 warn_for_div_by_zero (location, op1);
3472 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3474 /* Although it would be tempting to shorten always here, that loses
3475 on some targets, since the modulo instruction is undefined if the
3476 quotient can't be represented in the computation mode. We shorten
3477 only if unsigned or if dividing by something we know != -1. */
3478 shorten = ((TREE_CODE (op0) == NOP_EXPR
3479 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3480 || (TREE_CODE (op1) == INTEGER_CST
3481 && ! integer_all_onesp (op1)));
3486 case TRUTH_ANDIF_EXPR:
3487 case TRUTH_ORIF_EXPR:
3488 case TRUTH_AND_EXPR:
3490 result_type = boolean_type_node;
3493 /* Shift operations: result has same type as first operand;
3494 always convert second operand to int.
3495 Also set SHORT_SHIFT if shifting rightward. */
3498 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3500 result_type = type0;
3501 if (TREE_CODE (op1) == INTEGER_CST)
3503 if (tree_int_cst_lt (op1, integer_zero_node))
3505 if (complain & tf_warning)
3506 warning (0, "right shift count is negative");
3510 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3511 && (complain & tf_warning))
3512 warning (0, "right shift count >= width of type");
3515 /* Convert the shift-count to an integer, regardless of
3516 size of value being shifted. */
3517 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3518 op1 = cp_convert (integer_type_node, op1);
3519 /* Avoid converting op1 to result_type later. */
3525 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3527 result_type = type0;
3528 if (TREE_CODE (op1) == INTEGER_CST)
3530 if (tree_int_cst_lt (op1, integer_zero_node))
3532 if (complain & tf_warning)
3533 warning (0, "left shift count is negative");
3535 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3537 if (complain & tf_warning)
3538 warning (0, "left shift count >= width of type");
3541 /* Convert the shift-count to an integer, regardless of
3542 size of value being shifted. */
3543 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3544 op1 = cp_convert (integer_type_node, op1);
3545 /* Avoid converting op1 to result_type later. */
3552 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3554 result_type = type0;
3555 if (TREE_CODE (op1) == INTEGER_CST)
3557 if (tree_int_cst_lt (op1, integer_zero_node))
3559 if (complain & tf_warning)
3560 warning (0, (code == LROTATE_EXPR)
3561 ? G_("left rotate count is negative")
3562 : G_("right rotate count is negative"));
3564 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3566 if (complain & tf_warning)
3567 warning (0, (code == LROTATE_EXPR)
3568 ? G_("left rotate count >= width of type")
3569 : G_("right rotate count >= width of type"));
3572 /* Convert the shift-count to an integer, regardless of
3573 size of value being shifted. */
3574 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3575 op1 = cp_convert (integer_type_node, op1);
3581 if ((complain & tf_warning)
3582 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3583 warning (OPT_Wfloat_equal,
3584 "comparing floating point with == or != is unsafe");
3585 if ((complain & tf_warning)
3586 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3587 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3588 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3590 build_type = boolean_type_node;
3591 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3592 || code0 == COMPLEX_TYPE)
3593 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3594 || code1 == COMPLEX_TYPE))
3596 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3597 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3598 result_type = composite_pointer_type (type0, type1, op0, op1,
3599 "comparison", complain);
3600 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3601 && null_ptr_cst_p (op1))
3603 if (TREE_CODE (op0) == ADDR_EXPR
3604 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3606 if (complain & tf_warning)
3607 warning (OPT_Waddress, "the address of %qD will never be NULL",
3608 TREE_OPERAND (op0, 0));
3610 result_type = type0;
3612 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3613 && null_ptr_cst_p (op0))
3615 if (TREE_CODE (op1) == ADDR_EXPR
3616 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3618 if (complain & tf_warning)
3619 warning (OPT_Waddress, "the address of %qD will never be NULL",
3620 TREE_OPERAND (op1, 0));
3622 result_type = type1;
3624 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3626 result_type = type0;
3627 if (complain & tf_error)
3628 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3630 return error_mark_node;
3632 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3634 result_type = type1;
3635 if (complain & tf_error)
3636 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3638 return error_mark_node;
3640 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3642 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3643 == ptrmemfunc_vbit_in_delta)
3645 tree pfn0 = pfn_from_ptrmemfunc (op0);
3646 tree delta0 = delta_from_ptrmemfunc (op0);
3647 tree e1 = cp_build_binary_op (location,
3650 fold_convert (TREE_TYPE (pfn0),
3653 tree e2 = cp_build_binary_op (location,
3658 e2 = cp_build_binary_op (location,
3659 EQ_EXPR, e2, integer_zero_node,
3661 op0 = cp_build_binary_op (location,
3662 TRUTH_ANDIF_EXPR, e1, e2,
3664 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3668 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3669 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3671 result_type = TREE_TYPE (op0);
3673 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3674 return cp_build_binary_op (location, code, op1, op0, complain);
3675 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3678 /* E will be the final comparison. */
3680 /* E1 and E2 are for scratch. */
3688 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3691 if (!same_type_p (TREE_TYPE (op0), type))
3692 op0 = cp_convert_and_check (type, op0);
3693 if (!same_type_p (TREE_TYPE (op1), type))
3694 op1 = cp_convert_and_check (type, op1);
3696 if (op0 == error_mark_node || op1 == error_mark_node)
3697 return error_mark_node;
3699 if (TREE_SIDE_EFFECTS (op0))
3700 op0 = save_expr (op0);
3701 if (TREE_SIDE_EFFECTS (op1))
3702 op1 = save_expr (op1);
3704 pfn0 = pfn_from_ptrmemfunc (op0);
3705 pfn1 = pfn_from_ptrmemfunc (op1);
3706 delta0 = delta_from_ptrmemfunc (op0);
3707 delta1 = delta_from_ptrmemfunc (op1);
3708 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3709 == ptrmemfunc_vbit_in_delta)
3714 && ((op0.delta == op1.delta)
3715 || (!op0.pfn && op0.delta & 1 == 0
3716 && op1.delta & 1 == 0))
3718 The reason for the `!op0.pfn' bit is that a NULL
3719 pointer-to-member is any member with a zero PFN and
3720 LSB of the DELTA field is 0. */
3722 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3726 e1 = cp_build_binary_op (location,
3727 EQ_EXPR, e1, integer_zero_node,
3729 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3733 e2 = cp_build_binary_op (location,
3734 EQ_EXPR, e2, integer_zero_node,
3736 e1 = cp_build_binary_op (location,
3737 TRUTH_ANDIF_EXPR, e2, e1,
3739 e2 = cp_build_binary_op (location, EQ_EXPR,
3741 fold_convert (TREE_TYPE (pfn0),
3744 e2 = cp_build_binary_op (location,
3745 TRUTH_ANDIF_EXPR, e2, e1, complain);
3746 e1 = cp_build_binary_op (location,
3747 EQ_EXPR, delta0, delta1, complain);
3748 e1 = cp_build_binary_op (location,
3749 TRUTH_ORIF_EXPR, e1, e2, complain);
3756 && (!op0.pfn || op0.delta == op1.delta))
3758 The reason for the `!op0.pfn' bit is that a NULL
3759 pointer-to-member is any member with a zero PFN; the
3760 DELTA field is unspecified. */
3762 e1 = cp_build_binary_op (location,
3763 EQ_EXPR, delta0, delta1, complain);
3764 e2 = cp_build_binary_op (location,
3767 fold_convert (TREE_TYPE (pfn0),
3770 e1 = cp_build_binary_op (location,
3771 TRUTH_ORIF_EXPR, e1, e2, complain);
3773 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3774 e = cp_build_binary_op (location,
3775 TRUTH_ANDIF_EXPR, e2, e1, complain);
3776 if (code == EQ_EXPR)
3778 return cp_build_binary_op (location,
3779 EQ_EXPR, e, integer_zero_node, complain);
3783 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3784 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3786 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3787 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3795 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3796 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3798 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3799 result_type = composite_pointer_type (type0, type1, op0, op1,
3800 "comparison", complain);
3807 if (TREE_CODE (orig_op0) == STRING_CST
3808 || TREE_CODE (orig_op1) == STRING_CST)
3810 if (complain & tf_warning)
3811 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3814 build_type = boolean_type_node;
3815 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3816 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3818 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3819 result_type = composite_pointer_type (type0, type1, op0, op1,
3820 "comparison", complain);
3821 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3822 && integer_zerop (op1))
3823 result_type = type0;
3824 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3825 && integer_zerop (op0))
3826 result_type = type1;
3827 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3829 result_type = type0;
3830 if (complain & tf_error)
3831 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3833 return error_mark_node;
3835 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3837 result_type = type1;
3838 if (complain & tf_error)
3839 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3841 return error_mark_node;
3845 case UNORDERED_EXPR:
3852 build_type = integer_type_node;
3853 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3855 if (complain & tf_error)
3856 error ("unordered comparison on non-floating point argument");
3857 return error_mark_node;
3866 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3867 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3868 || code1 == COMPLEX_TYPE)))
3869 arithmetic_types_p = 1;
3872 arithmetic_types_p = 0;
3873 /* Vector arithmetic is only allowed when both sides are vectors. */
3874 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3876 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3877 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3880 binary_op_error (location, code, type0, type1);
3881 return error_mark_node;
3883 arithmetic_types_p = 1;
3886 /* Determine the RESULT_TYPE, if it is not already known. */
3888 && arithmetic_types_p
3889 && (shorten || common || short_compare))
3890 result_type = cp_common_type (type0, type1);
3894 if (complain & tf_error)
3895 error ("invalid operands of types %qT and %qT to binary %qO",
3896 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3897 return error_mark_node;
3900 /* If we're in a template, the only thing we need to know is the
3902 if (processing_template_decl)
3904 /* Since the middle-end checks the type when doing a build2, we
3905 need to build the tree in pieces. This built tree will never
3906 get out of the front-end as we replace it when instantiating
3908 tree tmp = build2 (resultcode,
3909 build_type ? build_type : result_type,
3911 TREE_OPERAND (tmp, 0) = op0;
3915 if (arithmetic_types_p)
3917 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3919 /* For certain operations (which identify themselves by shorten != 0)
3920 if both args were extended from the same smaller type,
3921 do the arithmetic in that type and then extend.
3923 shorten !=0 and !=1 indicates a bitwise operation.
3924 For them, this optimization is safe only if
3925 both args are zero-extended or both are sign-extended.
3926 Otherwise, we might change the result.
3927 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3928 but calculated in (unsigned short) it would be (unsigned short)-1. */
3930 if (shorten && none_complex)
3932 final_type = result_type;
3933 result_type = shorten_binary_op (result_type, op0, op1,
3937 /* Comparison operations are shortened too but differently.
3938 They identify themselves by setting short_compare = 1. */
3942 /* Don't write &op0, etc., because that would prevent op0
3943 from being kept in a register.
3944 Instead, make copies of the our local variables and
3945 pass the copies by reference, then copy them back afterward. */
3946 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3947 enum tree_code xresultcode = resultcode;
3949 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3951 return cp_convert (boolean_type_node, val);
3952 op0 = xop0, op1 = xop1;
3954 resultcode = xresultcode;
3957 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3958 && warn_sign_compare
3959 /* Do not warn until the template is instantiated; we cannot
3960 bound the ranges of the arguments until that point. */
3961 && !processing_template_decl
3962 && (complain & tf_warning))
3964 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
3965 result_type, resultcode);
3969 /* Issue warnings about peculiar, but valid, uses of NULL. */
3970 if ((orig_op0 == null_node || orig_op1 == null_node)
3971 /* It's reasonable to use pointer values as operands of &&
3972 and ||, so NULL is no exception. */
3973 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3974 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
3975 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3976 && code != EQ_EXPR && code != NE_EXPR)
3977 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3978 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3979 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
3980 && (complain & tf_warning))
3981 /* Some sort of arithmetic operation involving NULL was
3982 performed. Note that pointer-difference and pointer-addition
3983 have already been handled above, and so we don't end up here in
3985 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3988 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3989 Then the expression will be built.
3990 It will be given type FINAL_TYPE if that is nonzero;
3991 otherwise, it will be given type RESULT_TYPE. */
3994 if (TREE_TYPE (op0) != result_type)
3995 op0 = cp_convert_and_check (result_type, op0);
3996 if (TREE_TYPE (op1) != result_type)
3997 op1 = cp_convert_and_check (result_type, op1);
3999 if (op0 == error_mark_node || op1 == error_mark_node)
4000 return error_mark_node;
4003 if (build_type == NULL_TREE)
4004 build_type = result_type;
4006 result = build2 (resultcode, build_type, op0, op1);
4007 result = fold_if_not_in_template (result);
4008 if (final_type != 0)
4009 result = cp_convert (final_type, result);
4011 if (TREE_OVERFLOW_P (result)
4012 && !TREE_OVERFLOW_P (op0)
4013 && !TREE_OVERFLOW_P (op1))
4014 overflow_warning (result);
4019 /* Return a tree for the sum or difference (RESULTCODE says which)
4020 of pointer PTROP and integer INTOP. */
4023 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4025 tree res_type = TREE_TYPE (ptrop);
4027 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4028 in certain circumstance (when it's valid to do so). So we need
4029 to make sure it's complete. We don't need to check here, if we
4030 can actually complete it at all, as those checks will be done in
4031 pointer_int_sum() anyway. */
4032 complete_type (TREE_TYPE (res_type));
4034 return pointer_int_sum (input_location, resultcode, ptrop,
4035 fold_if_not_in_template (intop));
4038 /* Return a tree for the difference of pointers OP0 and OP1.
4039 The resulting tree has type int. */
4042 pointer_diff (tree op0, tree op1, tree ptrtype)
4045 tree restype = ptrdiff_type_node;
4046 tree target_type = TREE_TYPE (ptrtype);
4048 if (!complete_type_or_else (target_type, NULL_TREE))
4049 return error_mark_node;
4051 if (TREE_CODE (target_type) == VOID_TYPE)
4052 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4053 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4054 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4055 if (TREE_CODE (target_type) == METHOD_TYPE)
4056 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4058 /* First do the subtraction as integers;
4059 then drop through to build the divide operator. */
4061 op0 = cp_build_binary_op (input_location,
4063 cp_convert (restype, op0),
4064 cp_convert (restype, op1),
4065 tf_warning_or_error);
4067 /* This generates an error if op1 is a pointer to an incomplete type. */
4068 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4069 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4071 op1 = (TYPE_PTROB_P (ptrtype)
4072 ? size_in_bytes (target_type)
4073 : integer_one_node);
4075 /* Do the division. */
4077 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4078 return fold_if_not_in_template (result);
4081 /* Construct and perhaps optimize a tree representation
4082 for a unary operation. CODE, a tree_code, specifies the operation
4083 and XARG is the operand. */
4086 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4088 tree orig_expr = xarg;
4092 if (processing_template_decl)
4094 if (type_dependent_expression_p (xarg))
4095 return build_min_nt (code, xarg, NULL_TREE);
4097 xarg = build_non_dependent_expr (xarg);
4102 /* [expr.unary.op] says:
4104 The address of an object of incomplete type can be taken.
4106 (And is just the ordinary address operator, not an overloaded
4107 "operator &".) However, if the type is a template
4108 specialization, we must complete the type at this point so that
4109 an overloaded "operator &" will be available if required. */
4110 if (code == ADDR_EXPR
4111 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4112 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4113 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4114 || (TREE_CODE (xarg) == OFFSET_REF)))
4115 /* Don't look for a function. */;
4117 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4118 /*overloaded_p=*/NULL, complain);
4119 if (!exp && code == ADDR_EXPR)
4121 /* A pointer to member-function can be formed only by saying
4123 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4124 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4126 if (TREE_CODE (xarg) != OFFSET_REF
4127 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4129 error ("invalid use of %qE to form a pointer-to-member-function",
4131 if (TREE_CODE (xarg) != OFFSET_REF)
4132 inform (input_location, " a qualified-id is required");
4133 return error_mark_node;
4137 error ("parentheses around %qE cannot be used to form a"
4138 " pointer-to-member-function",
4140 PTRMEM_OK_P (xarg) = 1;
4144 if (TREE_CODE (xarg) == OFFSET_REF)
4146 ptrmem = PTRMEM_OK_P (xarg);
4148 if (!ptrmem && !flag_ms_extensions
4149 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4151 /* A single non-static member, make sure we don't allow a
4152 pointer-to-member. */
4153 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4154 TREE_OPERAND (xarg, 0),
4155 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4156 PTRMEM_OK_P (xarg) = ptrmem;
4159 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4160 warning (0, "taking address of temporary");
4161 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4164 if (processing_template_decl && exp != error_mark_node)
4165 exp = build_min_non_dep (code, exp, orig_expr,
4166 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4167 if (TREE_CODE (exp) == ADDR_EXPR)
4168 PTRMEM_OK_P (exp) = ptrmem;
4172 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4173 constants, where a null value is represented by an INTEGER_CST of
4177 cp_truthvalue_conversion (tree expr)
4179 tree type = TREE_TYPE (expr);
4180 if (TYPE_PTRMEM_P (type))
4181 return build_binary_op (EXPR_LOCATION (expr),
4182 NE_EXPR, expr, integer_zero_node, 1);
4184 return c_common_truthvalue_conversion (input_location, expr);
4187 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4190 condition_conversion (tree expr)
4193 if (processing_template_decl)
4195 t = perform_implicit_conversion (boolean_type_node, expr,
4196 tf_warning_or_error);
4197 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4201 /* Return an ADDR_EXPR giving the address of T. This function
4202 attempts no optimizations or simplifications; it is a low-level
4206 build_address (tree t)
4210 if (error_operand_p (t) || !cxx_mark_addressable (t))
4211 return error_mark_node;
4213 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4218 /* Return a NOP_EXPR converting EXPR to TYPE. */
4221 build_nop (tree type, tree expr)
4223 if (type == error_mark_node || error_operand_p (expr))
4225 return build1 (NOP_EXPR, type, expr);
4228 /* C++: Must handle pointers to members.
4230 Perhaps type instantiation should be extended to handle conversion
4231 from aggregates to types we don't yet know we want? (Or are those
4232 cases typically errors which should be reported?)
4234 NOCONVERT nonzero suppresses the default promotions
4235 (such as from short to int). */
4238 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4239 tsubst_flags_t complain)
4241 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4244 const char *errstring = NULL;
4246 const char *invalid_op_diag;
4248 if (error_operand_p (arg))
4249 return error_mark_node;
4251 if ((invalid_op_diag
4252 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4257 error (invalid_op_diag);
4258 return error_mark_node;
4263 case UNARY_PLUS_EXPR:
4266 int flags = WANT_ARITH | WANT_ENUM;
4267 /* Unary plus (but not unary minus) is allowed on pointers. */
4268 if (code == UNARY_PLUS_EXPR)
4269 flags |= WANT_POINTER;
4270 arg = build_expr_type_conversion (flags, arg, true);
4272 errstring = (code == NEGATE_EXPR
4273 ? "wrong type argument to unary minus"
4274 : "wrong type argument to unary plus");
4277 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4278 arg = perform_integral_promotions (arg);
4280 /* Make sure the result is not an lvalue: a unary plus or minus
4281 expression is always a rvalue. */
4288 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4292 arg = default_conversion (arg);
4294 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4297 errstring = "wrong type argument to bit-complement";
4298 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4299 arg = perform_integral_promotions (arg);
4303 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4304 errstring = "wrong type argument to abs";
4305 else if (!noconvert)
4306 arg = default_conversion (arg);
4310 /* Conjugating a real value is a no-op, but allow it anyway. */
4311 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4312 errstring = "wrong type argument to conjugation";
4313 else if (!noconvert)
4314 arg = default_conversion (arg);
4317 case TRUTH_NOT_EXPR:
4318 arg = perform_implicit_conversion (boolean_type_node, arg,
4320 val = invert_truthvalue (arg);
4321 if (arg != error_mark_node)
4323 errstring = "in argument to unary !";
4330 if (TREE_CODE (arg) == COMPLEX_CST)
4331 return TREE_REALPART (arg);
4332 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4334 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4335 return fold_if_not_in_template (arg);
4341 if (TREE_CODE (arg) == COMPLEX_CST)
4342 return TREE_IMAGPART (arg);
4343 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4345 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4346 return fold_if_not_in_template (arg);
4349 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4351 case PREINCREMENT_EXPR:
4352 case POSTINCREMENT_EXPR:
4353 case PREDECREMENT_EXPR:
4354 case POSTDECREMENT_EXPR:
4355 /* Handle complex lvalues (when permitted)
4356 by reduction to simpler cases. */
4358 val = unary_complex_lvalue (code, arg);
4362 /* Increment or decrement the real part of the value,
4363 and don't change the imaginary part. */
4364 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4368 arg = stabilize_reference (arg);
4369 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4370 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4371 real = cp_build_unary_op (code, real, 1, complain);
4372 if (real == error_mark_node || imag == error_mark_node)
4373 return error_mark_node;
4374 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4378 /* Report invalid types. */
4380 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4383 if (code == PREINCREMENT_EXPR)
4384 errstring ="no pre-increment operator for type";
4385 else if (code == POSTINCREMENT_EXPR)
4386 errstring ="no post-increment operator for type";
4387 else if (code == PREDECREMENT_EXPR)
4388 errstring ="no pre-decrement operator for type";
4390 errstring ="no post-decrement operator for type";
4393 else if (arg == error_mark_node)
4394 return error_mark_node;
4396 /* Report something read-only. */
4398 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4399 || TREE_READONLY (arg))
4401 if (complain & tf_error)
4402 readonly_error (arg, ((code == PREINCREMENT_EXPR
4403 || code == POSTINCREMENT_EXPR)
4404 ? "increment" : "decrement"));
4406 return error_mark_node;
4411 tree declared_type = unlowered_expr_type (arg);
4413 argtype = TREE_TYPE (arg);
4415 /* ARM $5.2.5 last annotation says this should be forbidden. */
4416 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4418 if (complain & tf_error)
4419 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4420 ? G_("ISO C++ forbids incrementing an enum")
4421 : G_("ISO C++ forbids decrementing an enum"));
4423 return error_mark_node;
4426 /* Compute the increment. */
4428 if (TREE_CODE (argtype) == POINTER_TYPE)
4430 tree type = complete_type (TREE_TYPE (argtype));
4432 if (!COMPLETE_OR_VOID_TYPE_P (type))
4434 if (complain & tf_error)
4435 error (((code == PREINCREMENT_EXPR
4436 || code == POSTINCREMENT_EXPR))
4437 ? G_("cannot increment a pointer to incomplete type %qT")
4438 : G_("cannot decrement a pointer to incomplete type %qT"),
4439 TREE_TYPE (argtype));
4441 return error_mark_node;
4443 else if ((pedantic || warn_pointer_arith)
4444 && !TYPE_PTROB_P (argtype))
4446 if (complain & tf_error)
4447 permerror (input_location, (code == PREINCREMENT_EXPR
4448 || code == POSTINCREMENT_EXPR)
4449 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4450 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4453 return error_mark_node;
4456 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4459 inc = integer_one_node;
4461 inc = cp_convert (argtype, inc);
4463 /* Complain about anything else that is not a true lvalue. */
4464 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4465 || code == POSTINCREMENT_EXPR)
4466 ? lv_increment : lv_decrement),
4468 return error_mark_node;
4470 /* Forbid using -- on `bool'. */
4471 if (same_type_p (declared_type, boolean_type_node))
4473 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4475 if (complain & tf_error)
4476 error ("invalid use of Boolean expression as operand "
4477 "to %<operator--%>");
4478 return error_mark_node;
4480 val = boolean_increment (code, arg);
4483 val = build2 (code, TREE_TYPE (arg), arg, inc);
4485 TREE_SIDE_EFFECTS (val) = 1;
4490 /* Note that this operation never does default_conversion
4491 regardless of NOCONVERT. */
4493 argtype = lvalue_type (arg);
4495 if (TREE_CODE (arg) == OFFSET_REF)
4498 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4500 tree type = build_pointer_type (TREE_TYPE (argtype));
4501 arg = build1 (CONVERT_EXPR, type, arg);
4504 else if (pedantic && DECL_MAIN_P (arg))
4507 /* Apparently a lot of autoconf scripts for C++ packages do this,
4508 so only complain if -pedantic. */
4509 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4510 pedwarn (input_location, OPT_pedantic,
4511 "ISO C++ forbids taking address of function %<::main%>");
4512 else if (flag_pedantic_errors)
4513 return error_mark_node;
4516 /* Let &* cancel out to simplify resulting code. */
4517 if (TREE_CODE (arg) == INDIRECT_REF)
4519 /* We don't need to have `current_class_ptr' wrapped in a
4520 NON_LVALUE_EXPR node. */
4521 if (arg == current_class_ref)
4522 return current_class_ptr;
4524 arg = TREE_OPERAND (arg, 0);
4525 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4527 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4528 arg = build1 (CONVERT_EXPR, type, arg);
4531 /* Don't let this be an lvalue. */
4536 /* Uninstantiated types are all functions. Taking the
4537 address of a function is a no-op, so just return the
4540 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4541 || !IDENTIFIER_OPNAME_P (arg));
4543 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4544 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4546 /* They're trying to take the address of a unique non-static
4547 member function. This is ill-formed (except in MS-land),
4548 but let's try to DTRT.
4549 Note: We only handle unique functions here because we don't
4550 want to complain if there's a static overload; non-unique
4551 cases will be handled by instantiate_type. But we need to
4552 handle this case here to allow casts on the resulting PMF.
4553 We could defer this in non-MS mode, but it's easier to give
4554 a useful error here. */
4556 /* Inside constant member functions, the `this' pointer
4557 contains an extra const qualifier. TYPE_MAIN_VARIANT
4558 is used here to remove this const from the diagnostics
4559 and the created OFFSET_REF. */
4560 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4561 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4564 if (! flag_ms_extensions)
4566 tree name = DECL_NAME (fn);
4567 if (!(complain & tf_error))
4568 return error_mark_node;
4569 else if (current_class_type
4570 && TREE_OPERAND (arg, 0) == current_class_ref)
4571 /* An expression like &memfn. */
4572 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4573 " or parenthesized non-static member function to form"
4574 " a pointer to member function. Say %<&%T::%D%>",
4577 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4578 " function to form a pointer to member function."
4582 arg = build_offset_ref (base, fn, /*address_p=*/true);
4586 if (type_unknown_p (arg))
4587 return build1 (ADDR_EXPR, unknown_type_node, arg);
4589 /* Handle complex lvalues (when permitted)
4590 by reduction to simpler cases. */
4591 val = unary_complex_lvalue (code, arg);
4595 switch (TREE_CODE (arg))
4599 case FIX_TRUNC_EXPR:
4600 /* Even if we're not being pedantic, we cannot allow this
4601 extension when we're instantiating in a SFINAE
4603 if (! lvalue_p (arg) && complain == tf_none)
4605 if (complain & tf_error)
4606 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4608 return error_mark_node;
4613 arg = BASELINK_FUNCTIONS (arg);
4617 arg = OVL_CURRENT (arg);
4621 /* Turn a reference to a non-static data member into a
4622 pointer-to-member. */
4627 if (!PTRMEM_OK_P (arg))
4628 return cp_build_unary_op (code, arg, 0, complain);
4630 t = TREE_OPERAND (arg, 1);
4631 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4633 if (complain & tf_error)
4634 error ("cannot create pointer to reference member %qD", t);
4635 return error_mark_node;
4638 type = build_ptrmem_type (context_for_name_lookup (t),
4640 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4648 /* Anything not already handled and not a true memory reference
4650 if (TREE_CODE (argtype) != FUNCTION_TYPE
4651 && TREE_CODE (argtype) != METHOD_TYPE
4652 && TREE_CODE (arg) != OFFSET_REF
4653 && !lvalue_or_else (arg, lv_addressof, complain))
4654 return error_mark_node;
4656 if (argtype != error_mark_node)
4657 argtype = build_pointer_type (argtype);
4659 /* In a template, we are processing a non-dependent expression
4660 so we can just form an ADDR_EXPR with the correct type. */
4661 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4663 val = build_address (arg);
4664 if (TREE_CODE (arg) == OFFSET_REF)
4665 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4667 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4669 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4671 /* We can only get here with a single static member
4673 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4674 && DECL_STATIC_FUNCTION_P (fn));
4676 val = build_address (fn);
4677 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4678 /* Do not lose object's side effects. */
4679 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4680 TREE_OPERAND (arg, 0), val);
4682 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4684 if (complain & tf_error)
4685 error ("attempt to take address of bit-field structure member %qD",
4686 TREE_OPERAND (arg, 1));
4687 return error_mark_node;
4691 tree object = TREE_OPERAND (arg, 0);
4692 tree field = TREE_OPERAND (arg, 1);
4693 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4694 (TREE_TYPE (object), decl_type_context (field)));
4695 val = build_address (arg);
4698 if (TREE_CODE (argtype) == POINTER_TYPE
4699 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4701 build_ptrmemfunc_type (argtype);
4702 val = build_ptrmemfunc (argtype, val, 0,
4703 /*c_cast_p=*/false);
4715 argtype = TREE_TYPE (arg);
4716 return fold_if_not_in_template (build1 (code, argtype, arg));
4719 if (complain & tf_error)
4720 error ("%s", errstring);
4721 return error_mark_node;
4724 /* Hook for the c-common bits that build a unary op. */
4726 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4727 enum tree_code code, tree xarg, int noconvert)
4729 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4732 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4733 for certain kinds of expressions which are not really lvalues
4734 but which we can accept as lvalues.
4736 If ARG is not a kind of expression we can handle, return
4740 unary_complex_lvalue (enum tree_code code, tree arg)
4742 /* Inside a template, making these kinds of adjustments is
4743 pointless; we are only concerned with the type of the
4745 if (processing_template_decl)
4748 /* Handle (a, b) used as an "lvalue". */
4749 if (TREE_CODE (arg) == COMPOUND_EXPR)
4751 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4752 tf_warning_or_error);
4753 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4754 TREE_OPERAND (arg, 0), real_result);
4757 /* Handle (a ? b : c) used as an "lvalue". */
4758 if (TREE_CODE (arg) == COND_EXPR
4759 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4760 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4762 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4763 if (TREE_CODE (arg) == MODIFY_EXPR
4764 || TREE_CODE (arg) == PREINCREMENT_EXPR
4765 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4767 tree lvalue = TREE_OPERAND (arg, 0);
4768 if (TREE_SIDE_EFFECTS (lvalue))
4770 lvalue = stabilize_reference (lvalue);
4771 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4772 lvalue, TREE_OPERAND (arg, 1));
4774 return unary_complex_lvalue
4775 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4778 if (code != ADDR_EXPR)
4781 /* Handle (a = b) used as an "lvalue" for `&'. */
4782 if (TREE_CODE (arg) == MODIFY_EXPR
4783 || TREE_CODE (arg) == INIT_EXPR)
4785 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4786 tf_warning_or_error);
4787 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4789 TREE_NO_WARNING (arg) = 1;
4793 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4794 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4795 || TREE_CODE (arg) == OFFSET_REF)
4798 /* We permit compiler to make function calls returning
4799 objects of aggregate type look like lvalues. */
4803 if (TREE_CODE (targ) == SAVE_EXPR)
4804 targ = TREE_OPERAND (targ, 0);
4806 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4808 if (TREE_CODE (arg) == SAVE_EXPR)
4811 targ = build_cplus_new (TREE_TYPE (arg), arg);
4812 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4815 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4816 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4817 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4820 /* Don't let anything else be handled specially. */
4824 /* Mark EXP saying that we need to be able to take the
4825 address of it; it should not be allocated in a register.
4826 Value is true if successful.
4828 C++: we do not allow `current_class_ptr' to be addressable. */
4831 cxx_mark_addressable (tree exp)
4836 switch (TREE_CODE (x))
4843 x = TREE_OPERAND (x, 0);
4847 if (x == current_class_ptr)
4849 error ("cannot take the address of %<this%>, which is an rvalue expression");
4850 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4856 /* Caller should not be trying to mark initialized
4857 constant fields addressable. */
4858 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4859 || DECL_IN_AGGR_P (x) == 0
4861 || DECL_EXTERNAL (x));
4866 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4867 && !DECL_ARTIFICIAL (x))
4869 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4872 ("address of explicit register variable %qD requested", x);
4875 else if (extra_warnings)
4877 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4879 TREE_ADDRESSABLE (x) = 1;
4883 TREE_ADDRESSABLE (x) = 1;
4887 TREE_ADDRESSABLE (x) = 1;
4891 TREE_ADDRESSABLE (x) = 1;
4892 cxx_mark_addressable (TREE_OPERAND (x, 0));
4900 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4903 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4904 tsubst_flags_t complain)
4906 tree orig_ifexp = ifexp;
4907 tree orig_op1 = op1;
4908 tree orig_op2 = op2;
4911 if (processing_template_decl)
4913 /* The standard says that the expression is type-dependent if
4914 IFEXP is type-dependent, even though the eventual type of the
4915 expression doesn't dependent on IFEXP. */
4916 if (type_dependent_expression_p (ifexp)
4917 /* As a GNU extension, the middle operand may be omitted. */
4918 || (op1 && type_dependent_expression_p (op1))
4919 || type_dependent_expression_p (op2))
4920 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4921 ifexp = build_non_dependent_expr (ifexp);
4923 op1 = build_non_dependent_expr (op1);
4924 op2 = build_non_dependent_expr (op2);
4927 expr = build_conditional_expr (ifexp, op1, op2, complain);
4928 if (processing_template_decl && expr != error_mark_node)
4929 return build_min_non_dep (COND_EXPR, expr,
4930 orig_ifexp, orig_op1, orig_op2);
4934 /* Given a list of expressions, return a compound expression
4935 that performs them all and returns the value of the last of them. */
4937 tree build_x_compound_expr_from_list (tree list, const char *msg)
4939 tree expr = TREE_VALUE (list);
4941 if (TREE_CHAIN (list))
4944 permerror (input_location, "%s expression list treated as compound expression", msg);
4946 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4947 expr = build_x_compound_expr (expr, TREE_VALUE (list),
4948 tf_warning_or_error);
4954 /* Handle overloading of the ',' operator when needed. */
4957 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
4960 tree orig_op1 = op1;
4961 tree orig_op2 = op2;
4963 if (processing_template_decl)
4965 if (type_dependent_expression_p (op1)
4966 || type_dependent_expression_p (op2))
4967 return build_min_nt (COMPOUND_EXPR, op1, op2);
4968 op1 = build_non_dependent_expr (op1);
4969 op2 = build_non_dependent_expr (op2);
4972 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4973 /*overloaded_p=*/NULL, complain);
4975 result = cp_build_compound_expr (op1, op2, complain);
4977 if (processing_template_decl && result != error_mark_node)
4978 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4983 /* Like cp_build_compound_expr, but for the c-common bits. */
4986 build_compound_expr (tree lhs, tree rhs)
4988 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
4991 /* Build a compound expression. */
4994 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
4996 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
4998 if (lhs == error_mark_node || rhs == error_mark_node)
4999 return error_mark_node;
5001 if (TREE_CODE (rhs) == TARGET_EXPR)
5003 /* If the rhs is a TARGET_EXPR, then build the compound
5004 expression inside the target_expr's initializer. This
5005 helps the compiler to eliminate unnecessary temporaries. */
5006 tree init = TREE_OPERAND (rhs, 1);
5008 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5009 TREE_OPERAND (rhs, 1) = init;
5014 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5017 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5018 casts away constness. CAST gives the type of cast. */
5021 check_for_casting_away_constness (tree src_type, tree dest_type,
5022 enum tree_code cast)
5024 /* C-style casts are allowed to cast away constness. With
5025 WARN_CAST_QUAL, we still want to issue a warning. */
5026 if (cast == CAST_EXPR && !warn_cast_qual)
5029 if (casts_away_constness (src_type, dest_type))
5033 warning (OPT_Wcast_qual,
5034 "cast from type %qT to type %qT casts away constness",
5035 src_type, dest_type);
5038 case STATIC_CAST_EXPR:
5039 error ("static_cast from type %qT to type %qT casts away constness",
5040 src_type, dest_type);
5043 case REINTERPRET_CAST_EXPR:
5044 error ("reinterpret_cast from type %qT to type %qT casts away constness",
5045 src_type, dest_type);
5052 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5053 (another pointer-to-member type in the same hierarchy) and return
5054 the converted expression. If ALLOW_INVERSE_P is permitted, a
5055 pointer-to-derived may be converted to pointer-to-base; otherwise,
5056 only the other direction is permitted. If C_CAST_P is true, this
5057 conversion is taking place as part of a C-style cast. */
5060 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5063 if (TYPE_PTRMEM_P (type))
5067 if (TREE_CODE (expr) == PTRMEM_CST)
5068 expr = cplus_expand_constant (expr);
5069 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5070 TYPE_PTRMEM_CLASS_TYPE (type),
5073 if (!integer_zerop (delta))
5075 tree cond, op1, op2;
5077 cond = cp_build_binary_op (input_location,
5080 build_int_cst (TREE_TYPE (expr), -1),
5081 tf_warning_or_error);
5082 op1 = build_nop (ptrdiff_type_node, expr);
5083 op2 = cp_build_binary_op (input_location,
5084 PLUS_EXPR, op1, delta,
5085 tf_warning_or_error);
5087 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5091 return build_nop (type, expr);
5094 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5095 allow_inverse_p, c_cast_p);
5098 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5099 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5100 Otherwise, return EXPR unchanged. */
5103 ignore_overflows (tree expr, tree orig)
5105 if (TREE_CODE (expr) == INTEGER_CST
5106 && CONSTANT_CLASS_P (orig)
5107 && TREE_CODE (orig) != STRING_CST
5108 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5110 if (!TREE_OVERFLOW (orig))
5111 /* Ensure constant sharing. */
5112 expr = build_int_cst_wide (TREE_TYPE (expr),
5113 TREE_INT_CST_LOW (expr),
5114 TREE_INT_CST_HIGH (expr));
5117 /* Avoid clobbering a shared constant. */
5118 expr = copy_node (expr);
5119 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5125 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5126 this static_cast is being attempted as one of the possible casts
5127 allowed by a C-style cast. (In that case, accessibility of base
5128 classes is not considered, and it is OK to cast away
5129 constness.) Return the result of the cast. *VALID_P is set to
5130 indicate whether or not the cast was valid. */
5133 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5134 bool *valid_p, tsubst_flags_t complain)
5140 /* Assume the cast is valid. */
5143 intype = TREE_TYPE (expr);
5145 /* Save casted types in the function's used types hash table. */
5146 used_types_insert (type);
5148 /* [expr.static.cast]
5150 An lvalue of type "cv1 B", where B is a class type, can be cast
5151 to type "reference to cv2 D", where D is a class derived (clause
5152 _class.derived_) from B, if a valid standard conversion from
5153 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5154 same cv-qualification as, or greater cv-qualification than, cv1,
5155 and B is not a virtual base class of D. */
5156 /* We check this case before checking the validity of "TYPE t =
5157 EXPR;" below because for this case:
5160 struct D : public B { D(const B&); };
5162 void f() { static_cast<const D&>(b); }
5164 we want to avoid constructing a new D. The standard is not
5165 completely clear about this issue, but our interpretation is
5166 consistent with other compilers. */
5167 if (TREE_CODE (type) == REFERENCE_TYPE
5168 && CLASS_TYPE_P (TREE_TYPE (type))
5169 && CLASS_TYPE_P (intype)
5170 && real_lvalue_p (expr)
5171 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5172 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5173 build_pointer_type (TYPE_MAIN_VARIANT
5174 (TREE_TYPE (type))))
5176 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5180 /* There is a standard conversion from "D*" to "B*" even if "B"
5181 is ambiguous or inaccessible. If this is really a
5182 static_cast, then we check both for inaccessibility and
5183 ambiguity. However, if this is a static_cast being performed
5184 because the user wrote a C-style cast, then accessibility is
5186 base = lookup_base (TREE_TYPE (type), intype,
5187 c_cast_p ? ba_unique : ba_check,
5190 /* Convert from "B*" to "D*". This function will check that "B"
5191 is not a virtual base of "D". */
5192 expr = build_base_path (MINUS_EXPR, build_address (expr),
5193 base, /*nonnull=*/false);
5194 /* Convert the pointer to a reference -- but then remember that
5195 there are no expressions with reference type in C++. */
5196 return convert_from_reference (build_nop (type, expr));
5201 /* [expr.static.cast]
5203 An expression e can be explicitly converted to a type T using a
5204 static_cast of the form static_cast<T>(e) if the declaration T
5205 t(e);" is well-formed, for some invented temporary variable
5207 result = perform_direct_initialization_if_possible (type, expr,
5208 c_cast_p, complain);
5211 result = convert_from_reference (result);
5213 /* Ignore any integer overflow caused by the cast. */
5214 result = ignore_overflows (result, orig);
5216 /* [expr.static.cast]
5218 If T is a reference type, the result is an lvalue; otherwise,
5219 the result is an rvalue. */
5220 if (TREE_CODE (type) != REFERENCE_TYPE)
5221 result = rvalue (result);
5225 /* [expr.static.cast]
5227 Any expression can be explicitly converted to type cv void. */
5228 if (TREE_CODE (type) == VOID_TYPE)
5229 return convert_to_void (expr, /*implicit=*/NULL, complain);
5231 /* [expr.static.cast]
5233 The inverse of any standard conversion sequence (clause _conv_),
5234 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5235 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5236 (_conv.bool_) conversions, can be performed explicitly using
5237 static_cast subject to the restriction that the explicit
5238 conversion does not cast away constness (_expr.const.cast_), and
5239 the following additional rules for specific cases: */
5240 /* For reference, the conversions not excluded are: integral
5241 promotions, floating point promotion, integral conversions,
5242 floating point conversions, floating-integral conversions,
5243 pointer conversions, and pointer to member conversions. */
5246 A value of integral _or enumeration_ type can be explicitly
5247 converted to an enumeration type. */
5248 /* The effect of all that is that any conversion between any two
5249 types which are integral, floating, or enumeration types can be
5251 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
5252 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
5254 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5256 /* Ignore any integer overflow caused by the cast. */
5257 expr = ignore_overflows (expr, orig);
5261 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5262 && CLASS_TYPE_P (TREE_TYPE (type))
5263 && CLASS_TYPE_P (TREE_TYPE (intype))
5264 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5265 (TREE_TYPE (intype))),
5266 build_pointer_type (TYPE_MAIN_VARIANT
5267 (TREE_TYPE (type)))))
5272 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5273 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5274 c_cast_p ? ba_unique : ba_check,
5276 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5279 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5280 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5287 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5288 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5290 if (TYPE_PTRMEM_P (type))
5292 t1 = (build_ptrmem_type
5294 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5295 t2 = (build_ptrmem_type
5297 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5304 if (can_convert (t1, t2) || can_convert (t2, t1))
5307 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5308 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5313 /* [expr.static.cast]
5315 An rvalue of type "pointer to cv void" can be explicitly
5316 converted to a pointer to object type. A value of type pointer
5317 to object converted to "pointer to cv void" and back to the
5318 original pointer type will have its original value. */
5319 if (TREE_CODE (intype) == POINTER_TYPE
5320 && VOID_TYPE_P (TREE_TYPE (intype))
5321 && TYPE_PTROB_P (type))
5324 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5325 return build_nop (type, expr);
5329 return error_mark_node;
5332 /* Return an expression representing static_cast<TYPE>(EXPR). */
5335 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5340 if (type == error_mark_node || expr == error_mark_node)
5341 return error_mark_node;
5343 if (processing_template_decl)
5345 expr = build_min (STATIC_CAST_EXPR, type, expr);
5346 /* We don't know if it will or will not have side effects. */
5347 TREE_SIDE_EFFECTS (expr) = 1;
5348 return convert_from_reference (expr);
5351 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5352 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5353 if (TREE_CODE (type) != REFERENCE_TYPE
5354 && TREE_CODE (expr) == NOP_EXPR
5355 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5356 expr = TREE_OPERAND (expr, 0);
5358 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5363 if (complain & tf_error)
5364 error ("invalid static_cast from type %qT to type %qT",
5365 TREE_TYPE (expr), type);
5366 return error_mark_node;
5369 /* EXPR is an expression with member function or pointer-to-member
5370 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5371 not permitted by ISO C++, but we accept it in some modes. If we
5372 are not in one of those modes, issue a diagnostic. Return the
5373 converted expression. */
5376 convert_member_func_to_ptr (tree type, tree expr)
5381 intype = TREE_TYPE (expr);
5382 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5383 || TREE_CODE (intype) == METHOD_TYPE);
5385 if (pedantic || warn_pmf2ptr)
5386 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5387 "converting from %qT to %qT", intype, type);
5389 if (TREE_CODE (intype) == METHOD_TYPE)
5390 expr = build_addr_func (expr);
5391 else if (TREE_CODE (expr) == PTRMEM_CST)
5392 expr = build_address (PTRMEM_CST_MEMBER (expr));
5395 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5396 decl = build_address (decl);
5397 expr = get_member_function_from_ptrfunc (&decl, expr);
5400 return build_nop (type, expr);
5403 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5404 If C_CAST_P is true, this reinterpret cast is being done as part of
5405 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5406 indicate whether or not reinterpret_cast was valid. */
5409 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5410 bool *valid_p, tsubst_flags_t complain)
5414 /* Assume the cast is invalid. */
5418 if (type == error_mark_node || error_operand_p (expr))
5419 return error_mark_node;
5421 intype = TREE_TYPE (expr);
5423 /* Save casted types in the function's used types hash table. */
5424 used_types_insert (type);
5426 /* [expr.reinterpret.cast]
5427 An lvalue expression of type T1 can be cast to the type
5428 "reference to T2" if an expression of type "pointer to T1" can be
5429 explicitly converted to the type "pointer to T2" using a
5430 reinterpret_cast. */
5431 if (TREE_CODE (type) == REFERENCE_TYPE)
5433 if (! real_lvalue_p (expr))
5435 if (complain & tf_error)
5436 error ("invalid cast of an rvalue expression of type "
5439 return error_mark_node;
5442 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5443 "B" are related class types; the reinterpret_cast does not
5444 adjust the pointer. */
5445 if (TYPE_PTR_P (intype)
5446 && (complain & tf_warning)
5447 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5448 COMPARE_BASE | COMPARE_DERIVED)))
5449 warning (0, "casting %qT to %qT does not dereference pointer",
5452 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5453 if (expr != error_mark_node)
5454 expr = build_reinterpret_cast_1
5455 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5457 if (expr != error_mark_node)
5458 expr = cp_build_indirect_ref (expr, 0, complain);
5462 /* As a G++ extension, we consider conversions from member
5463 functions, and pointers to member functions to
5464 pointer-to-function and pointer-to-void types. If
5465 -Wno-pmf-conversions has not been specified,
5466 convert_member_func_to_ptr will issue an error message. */
5467 if ((TYPE_PTRMEMFUNC_P (intype)
5468 || TREE_CODE (intype) == METHOD_TYPE)
5469 && TYPE_PTR_P (type)
5470 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5471 || VOID_TYPE_P (TREE_TYPE (type))))
5472 return convert_member_func_to_ptr (type, expr);
5474 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5475 array-to-pointer, and function-to-pointer conversions are
5477 expr = decay_conversion (expr);
5479 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5480 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5481 if (TREE_CODE (expr) == NOP_EXPR
5482 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5483 expr = TREE_OPERAND (expr, 0);
5485 if (error_operand_p (expr))
5486 return error_mark_node;
5488 intype = TREE_TYPE (expr);
5490 /* [expr.reinterpret.cast]
5491 A pointer can be converted to any integral type large enough to
5493 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5495 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5497 if (complain & tf_error)
5498 permerror (input_location, "cast from %qT to %qT loses precision",
5501 return error_mark_node;
5504 /* [expr.reinterpret.cast]
5505 A value of integral or enumeration type can be explicitly
5506 converted to a pointer. */
5507 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5510 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5511 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5512 return fold_if_not_in_template (build_nop (type, expr));
5513 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5514 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5519 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5520 /* Warn about possible alignment problems. */
5521 if (STRICT_ALIGNMENT && warn_cast_align
5522 && (complain & tf_warning)
5523 && !VOID_TYPE_P (type)
5524 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5525 && COMPLETE_TYPE_P (TREE_TYPE (type))
5526 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5527 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5528 warning (OPT_Wcast_align, "cast from %qT to %qT "
5529 "increases required alignment of target type", intype, type);
5531 /* We need to strip nops here, because the front end likes to
5532 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5534 if (warn_strict_aliasing <= 2)
5535 strict_aliasing_warning (intype, type, sexpr);
5537 return fold_if_not_in_template (build_nop (type, expr));
5539 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5540 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5542 if (pedantic && (complain & tf_warning))
5543 /* Only issue a warning, as we have always supported this
5544 where possible, and it is necessary in some cases. DR 195
5545 addresses this issue, but as of 2004/10/26 is still in
5547 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5548 return fold_if_not_in_template (build_nop (type, expr));
5550 else if (TREE_CODE (type) == VECTOR_TYPE)
5551 return fold_if_not_in_template (convert_to_vector (type, expr));
5552 else if (TREE_CODE (intype) == VECTOR_TYPE && INTEGRAL_TYPE_P (type))
5553 return fold_if_not_in_template (convert_to_integer (type, expr));
5558 if (complain & tf_error)
5559 error ("invalid cast from type %qT to type %qT", intype, type);
5560 return error_mark_node;
5563 return cp_convert (type, expr);
5567 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5569 if (type == error_mark_node || expr == error_mark_node)
5570 return error_mark_node;
5572 if (processing_template_decl)
5574 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5576 if (!TREE_SIDE_EFFECTS (t)
5577 && type_dependent_expression_p (expr))
5578 /* There might turn out to be side effects inside expr. */
5579 TREE_SIDE_EFFECTS (t) = 1;
5580 return convert_from_reference (t);
5583 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5584 /*valid_p=*/NULL, complain);
5587 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5588 return an appropriate expression. Otherwise, return
5589 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5590 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5591 performing a C-style cast, its value upon return will indicate
5592 whether or not the conversion succeeded. */
5595 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5599 tree reference_type;
5601 /* Callers are responsible for handling error_mark_node as a
5602 destination type. */
5603 gcc_assert (dst_type != error_mark_node);
5604 /* In a template, callers should be building syntactic
5605 representations of casts, not using this machinery. */
5606 gcc_assert (!processing_template_decl);
5608 /* Assume the conversion is invalid. */
5612 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5615 error ("invalid use of const_cast with type %qT, "
5616 "which is not a pointer, "
5617 "reference, nor a pointer-to-data-member type", dst_type);
5618 return error_mark_node;
5621 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5624 error ("invalid use of const_cast with type %qT, which is a pointer "
5625 "or reference to a function type", dst_type);
5626 return error_mark_node;
5629 /* Save casted types in the function's used types hash table. */
5630 used_types_insert (dst_type);
5632 src_type = TREE_TYPE (expr);
5633 /* Expressions do not really have reference types. */
5634 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5635 src_type = TREE_TYPE (src_type);
5637 /* [expr.const.cast]
5639 An lvalue of type T1 can be explicitly converted to an lvalue of
5640 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5641 types) if a pointer to T1 can be explicitly converted to the type
5642 pointer to T2 using a const_cast. */
5643 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5645 reference_type = dst_type;
5646 if (! real_lvalue_p (expr))
5649 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5650 src_type, dst_type);
5651 return error_mark_node;
5653 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5654 src_type = build_pointer_type (src_type);
5658 reference_type = NULL_TREE;
5659 /* If the destination type is not a reference type, the
5660 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5661 conversions are performed. */
5662 src_type = type_decays_to (src_type);
5663 if (src_type == error_mark_node)
5664 return error_mark_node;
5667 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5668 && comp_ptr_ttypes_const (dst_type, src_type))
5673 /* This cast is actually a C-style cast. Issue a warning if
5674 the user is making a potentially unsafe cast. */
5675 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5679 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5680 complain? tf_warning_or_error : tf_none);
5681 expr = build_nop (reference_type, expr);
5682 return convert_from_reference (expr);
5686 expr = decay_conversion (expr);
5687 /* build_c_cast puts on a NOP_EXPR to make the result not an
5688 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5689 non-lvalue context. */
5690 if (TREE_CODE (expr) == NOP_EXPR
5691 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5692 expr = TREE_OPERAND (expr, 0);
5693 return build_nop (dst_type, expr);
5698 error ("invalid const_cast from type %qT to type %qT",
5699 src_type, dst_type);
5700 return error_mark_node;
5704 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5706 if (type == error_mark_node || error_operand_p (expr))
5707 return error_mark_node;
5709 if (processing_template_decl)
5711 tree t = build_min (CONST_CAST_EXPR, type, expr);
5713 if (!TREE_SIDE_EFFECTS (t)
5714 && type_dependent_expression_p (expr))
5715 /* There might turn out to be side effects inside expr. */
5716 TREE_SIDE_EFFECTS (t) = 1;
5717 return convert_from_reference (t);
5720 return build_const_cast_1 (type, expr, complain & tf_error,
5724 /* Like cp_build_c_cast, but for the c-common bits. */
5727 build_c_cast (tree type, tree expr)
5729 return cp_build_c_cast (type, expr, tf_warning_or_error);
5732 /* Build an expression representing an explicit C-style cast to type
5733 TYPE of expression EXPR. */
5736 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5742 if (type == error_mark_node || error_operand_p (expr))
5743 return error_mark_node;
5745 if (processing_template_decl)
5747 tree t = build_min (CAST_EXPR, type,
5748 tree_cons (NULL_TREE, value, NULL_TREE));
5749 /* We don't know if it will or will not have side effects. */
5750 TREE_SIDE_EFFECTS (t) = 1;
5751 return convert_from_reference (t);
5754 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5755 'Class') should always be retained, because this information aids
5756 in method lookup. */
5757 if (objc_is_object_ptr (type)
5758 && objc_is_object_ptr (TREE_TYPE (expr)))
5759 return build_nop (type, expr);
5761 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5762 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5763 if (TREE_CODE (type) != REFERENCE_TYPE
5764 && TREE_CODE (value) == NOP_EXPR
5765 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5766 value = TREE_OPERAND (value, 0);
5768 if (TREE_CODE (type) == ARRAY_TYPE)
5770 /* Allow casting from T1* to T2[] because Cfront allows it.
5771 NIHCL uses it. It is not valid ISO C++ however. */
5772 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5774 if (complain & tf_error)
5775 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5777 return error_mark_node;
5778 type = build_pointer_type (TREE_TYPE (type));
5782 if (complain & tf_error)
5783 error ("ISO C++ forbids casting to an array type %qT", type);
5784 return error_mark_node;
5788 if (TREE_CODE (type) == FUNCTION_TYPE
5789 || TREE_CODE (type) == METHOD_TYPE)
5791 if (complain & tf_error)
5792 error ("invalid cast to function type %qT", type);
5793 return error_mark_node;
5796 /* A C-style cast can be a const_cast. */
5797 result = build_const_cast_1 (type, value, /*complain=*/false,
5802 /* Or a static cast. */
5803 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5804 &valid_p, complain);
5805 /* Or a reinterpret_cast. */
5807 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5808 &valid_p, complain);
5809 /* The static_cast or reinterpret_cast may be followed by a
5812 /* A valid cast may result in errors if, for example, a
5813 conversion to am ambiguous base class is required. */
5814 && !error_operand_p (result))
5818 /* Non-class rvalues always have cv-unqualified type. */
5819 if (!CLASS_TYPE_P (type))
5820 type = TYPE_MAIN_VARIANT (type);
5821 result_type = TREE_TYPE (result);
5822 if (!CLASS_TYPE_P (result_type))
5823 result_type = TYPE_MAIN_VARIANT (result_type);
5824 /* If the type of RESULT does not match TYPE, perform a
5825 const_cast to make it match. If the static_cast or
5826 reinterpret_cast succeeded, we will differ by at most
5827 cv-qualification, so the follow-on const_cast is guaranteed
5829 if (!same_type_p (non_reference (type), non_reference (result_type)))
5831 result = build_const_cast_1 (type, result, false, &valid_p);
5832 gcc_assert (valid_p);
5837 return error_mark_node;
5840 /* For use from the C common bits. */
5842 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5843 tree lhs, enum tree_code modifycode, tree rhs)
5845 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5848 /* Build an assignment expression of lvalue LHS from value RHS.
5849 MODIFYCODE is the code for a binary operator that we use
5850 to combine the old value of LHS with RHS to get the new value.
5851 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5853 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5856 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5857 tsubst_flags_t complain)
5861 tree lhstype = TREE_TYPE (lhs);
5862 tree olhstype = lhstype;
5863 bool plain_assign = (modifycode == NOP_EXPR);
5865 /* Avoid duplicate error messages from operands that had errors. */
5866 if (error_operand_p (lhs) || error_operand_p (rhs))
5867 return error_mark_node;
5869 /* Handle control structure constructs used as "lvalues". */
5870 switch (TREE_CODE (lhs))
5872 /* Handle --foo = 5; as these are valid constructs in C++. */
5873 case PREDECREMENT_EXPR:
5874 case PREINCREMENT_EXPR:
5875 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5876 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5877 stabilize_reference (TREE_OPERAND (lhs, 0)),
5878 TREE_OPERAND (lhs, 1));
5879 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
5880 modifycode, rhs, complain);
5881 if (newrhs == error_mark_node)
5882 return error_mark_node;
5883 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5885 /* Handle (a, b) used as an "lvalue". */
5887 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5888 modifycode, rhs, complain);
5889 if (newrhs == error_mark_node)
5890 return error_mark_node;
5891 return build2 (COMPOUND_EXPR, lhstype,
5892 TREE_OPERAND (lhs, 0), newrhs);
5895 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5896 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5897 stabilize_reference (TREE_OPERAND (lhs, 0)),
5898 TREE_OPERAND (lhs, 1));
5899 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
5901 if (newrhs == error_mark_node)
5902 return error_mark_node;
5903 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5907 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5908 when neither operand has side-effects. */
5909 if (!lvalue_or_else (lhs, lv_assign, complain))
5910 return error_mark_node;
5912 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5913 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5915 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5916 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5918 TREE_OPERAND (lhs, 0),
5919 TREE_OPERAND (lhs, 1)),
5920 TREE_OPERAND (lhs, 0),
5921 TREE_OPERAND (lhs, 1));
5924 /* Handle (a ? b : c) used as an "lvalue". */
5927 /* Produce (a ? (b = rhs) : (c = rhs))
5928 except that the RHS goes through a save-expr
5929 so the code to compute it is only emitted once. */
5931 tree preeval = NULL_TREE;
5933 if (VOID_TYPE_P (TREE_TYPE (rhs)))
5935 if (complain & tf_error)
5936 error ("void value not ignored as it ought to be");
5937 return error_mark_node;
5940 rhs = stabilize_expr (rhs, &preeval);
5942 /* Check this here to avoid odd errors when trying to convert
5943 a throw to the type of the COND_EXPR. */
5944 if (!lvalue_or_else (lhs, lv_assign, complain))
5945 return error_mark_node;
5947 cond = build_conditional_expr
5948 (TREE_OPERAND (lhs, 0),
5949 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5950 modifycode, rhs, complain),
5951 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
5952 modifycode, rhs, complain),
5955 if (cond == error_mark_node)
5957 /* Make sure the code to compute the rhs comes out
5958 before the split. */
5960 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5968 if (modifycode == INIT_EXPR)
5970 if (TREE_CODE (rhs) == CONSTRUCTOR)
5972 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5973 /* Call convert to generate an error; see PR 11063. */
5974 rhs = convert (lhstype, rhs);
5975 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5976 TREE_SIDE_EFFECTS (result) = 1;
5979 else if (! MAYBE_CLASS_TYPE_P (lhstype))
5980 /* Do the default thing. */;
5983 result = build_special_member_call (lhs, complete_ctor_identifier,
5984 build_tree_list (NULL_TREE, rhs),
5985 lhstype, LOOKUP_NORMAL,
5987 if (result == NULL_TREE)
5988 return error_mark_node;
5994 lhs = require_complete_type (lhs);
5995 if (lhs == error_mark_node)
5996 return error_mark_node;
5998 if (modifycode == NOP_EXPR)
6000 /* `operator=' is not an inheritable operator. */
6001 if (! MAYBE_CLASS_TYPE_P (lhstype))
6002 /* Do the default thing. */;
6005 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6006 lhs, rhs, make_node (NOP_EXPR),
6007 /*overloaded_p=*/NULL,
6009 if (result == NULL_TREE)
6010 return error_mark_node;
6017 /* A binary op has been requested. Combine the old LHS
6018 value with the RHS producing the value we should actually
6019 store into the LHS. */
6020 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6021 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6022 || MAYBE_CLASS_TYPE_P (lhstype)));
6024 lhs = stabilize_reference (lhs);
6025 newrhs = cp_build_binary_op (input_location,
6026 modifycode, lhs, rhs,
6028 if (newrhs == error_mark_node)
6030 if (complain & tf_error)
6031 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6032 TREE_TYPE (lhs), TREE_TYPE (rhs));
6033 return error_mark_node;
6036 /* Now it looks like a plain assignment. */
6037 modifycode = NOP_EXPR;
6039 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6040 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6043 /* The left-hand side must be an lvalue. */
6044 if (!lvalue_or_else (lhs, lv_assign, complain))
6045 return error_mark_node;
6047 /* Warn about modifying something that is `const'. Don't warn if
6048 this is initialization. */
6049 if (modifycode != INIT_EXPR
6050 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6051 /* Functions are not modifiable, even though they are
6053 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6054 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6055 /* If it's an aggregate and any field is const, then it is
6056 effectively const. */
6057 || (CLASS_TYPE_P (lhstype)
6058 && C_TYPE_FIELDS_READONLY (lhstype))))
6060 if (complain & tf_error)
6061 readonly_error (lhs, "assignment");
6063 return error_mark_node;
6066 /* If storing into a structure or union member, it may have been given a
6067 lowered bitfield type. We need to convert to the declared type first,
6068 so retrieve it now. */
6070 olhstype = unlowered_expr_type (lhs);
6072 /* Convert new value to destination type. */
6074 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6078 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6079 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6081 if (complain & tf_error)
6082 error ("incompatible types in assignment of %qT to %qT",
6083 TREE_TYPE (rhs), lhstype);
6084 return error_mark_node;
6087 /* Allow array assignment in compiler-generated code. */
6088 if (!current_function_decl || !DECL_ARTIFICIAL (current_function_decl))
6090 /* This routine is used for both initialization and assignment.
6091 Make sure the diagnostic message differentiates the context. */
6092 if (complain & tf_error)
6094 if (modifycode == INIT_EXPR)
6095 error ("array used as initializer");
6097 error ("invalid array assignment");
6099 return error_mark_node;
6102 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6103 ? 1 + (modifycode != INIT_EXPR): 0;
6104 return build_vec_init (lhs, NULL_TREE, newrhs,
6105 /*explicit_value_init_p=*/false,
6106 from_array, complain);
6109 if (modifycode == INIT_EXPR)
6110 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6111 "initialization", NULL_TREE, 0,
6114 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6115 NULL_TREE, 0, complain);
6117 if (!same_type_p (lhstype, olhstype))
6118 newrhs = cp_convert_and_check (lhstype, newrhs);
6120 if (modifycode != INIT_EXPR)
6122 if (TREE_CODE (newrhs) == CALL_EXPR
6123 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6124 newrhs = build_cplus_new (lhstype, newrhs);
6126 /* Can't initialize directly from a TARGET_EXPR, since that would
6127 cause the lhs to be constructed twice, and possibly result in
6128 accidental self-initialization. So we force the TARGET_EXPR to be
6129 expanded without a target. */
6130 if (TREE_CODE (newrhs) == TARGET_EXPR)
6131 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6132 TREE_OPERAND (newrhs, 0));
6135 if (newrhs == error_mark_node)
6136 return error_mark_node;
6138 if (c_dialect_objc () && flag_objc_gc)
6140 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6146 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6147 lhstype, lhs, newrhs);
6149 TREE_SIDE_EFFECTS (result) = 1;
6151 TREE_NO_WARNING (result) = 1;
6157 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6158 tsubst_flags_t complain)
6160 if (processing_template_decl)
6161 return build_min_nt (MODOP_EXPR, lhs,
6162 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6164 if (modifycode != NOP_EXPR)
6166 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6167 make_node (modifycode),
6168 /*overloaded_p=*/NULL,
6172 TREE_NO_WARNING (rval) = 1;
6176 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6179 /* Helper function for get_delta_difference which assumes FROM is a base
6180 class of TO. Returns a delta for the conversion of pointer-to-member
6181 of FROM to pointer-to-member of TO. If the conversion is invalid,
6182 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6183 If C_CAST_P is true, this conversion is taking place as part of a C-style
6187 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6192 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6193 if (kind == bk_inaccessible || kind == bk_ambig)
6195 error (" in pointer to member function conversion");
6196 return size_zero_node;
6200 if (kind != bk_via_virtual)
6201 return BINFO_OFFSET (binfo);
6203 /* FROM is a virtual base class of TO. Issue an error or warning
6204 depending on whether or not this is a reinterpret cast. */
6206 error ("pointer to member conversion via virtual base %qT",
6207 BINFO_TYPE (binfo_from_vbase (binfo)));
6209 return size_zero_node;
6216 /* Get difference in deltas for different pointer to member function
6217 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6218 the conversion is invalid, the constant is zero. If
6219 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6220 If C_CAST_P is true this conversion is taking place as part of a
6223 Note that the naming of FROM and TO is kind of backwards; the return
6224 value is what we add to a TO in order to get a FROM. They are named
6225 this way because we call this function to find out how to convert from
6226 a pointer to member of FROM to a pointer to member of TO. */
6229 get_delta_difference (tree from, tree to,
6230 bool allow_inverse_p,
6235 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6236 /* Pointer to member of incomplete class is permitted*/
6237 result = size_zero_node;
6239 result = get_delta_difference_1 (from, to, c_cast_p);
6243 if (!allow_inverse_p)
6245 error_not_base_type (from, to);
6246 error (" in pointer to member conversion");
6247 result = size_zero_node;
6251 result = get_delta_difference_1 (to, from, c_cast_p);
6254 result = size_diffop (size_zero_node, result);
6257 error_not_base_type (from, to);
6258 error (" in pointer to member conversion");
6259 result = size_zero_node;
6264 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6268 /* Return a constructor for the pointer-to-member-function TYPE using
6269 the other components as specified. */
6272 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6277 VEC(constructor_elt, gc) *v;
6279 /* Pull the FIELD_DECLs out of the type. */
6280 pfn_field = TYPE_FIELDS (type);
6281 delta_field = TREE_CHAIN (pfn_field);
6283 /* Make sure DELTA has the type we want. */
6284 delta = convert_and_check (delta_type_node, delta);
6286 /* Convert to the correct target type if necessary. */
6287 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6289 /* Finish creating the initializer. */
6290 v = VEC_alloc(constructor_elt, gc, 2);
6291 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6292 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6293 u = build_constructor (type, v);
6294 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6295 TREE_STATIC (u) = (TREE_CONSTANT (u)
6296 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6298 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6303 /* Build a constructor for a pointer to member function. It can be
6304 used to initialize global variables, local variable, or used
6305 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6308 If FORCE is nonzero, then force this conversion, even if
6309 we would rather not do it. Usually set when using an explicit
6310 cast. A C-style cast is being processed iff C_CAST_P is true.
6312 Return error_mark_node, if something goes wrong. */
6315 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6321 if (error_operand_p (pfn))
6322 return error_mark_node;
6324 pfn_type = TREE_TYPE (pfn);
6325 to_type = build_ptrmemfunc_type (type);
6327 /* Handle multiple conversions of pointer to member functions. */
6328 if (TYPE_PTRMEMFUNC_P (pfn_type))
6330 tree delta = NULL_TREE;
6331 tree npfn = NULL_TREE;
6335 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6336 error ("invalid conversion to type %qT from type %qT",
6339 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6340 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6344 /* We don't have to do any conversion to convert a
6345 pointer-to-member to its own type. But, we don't want to
6346 just return a PTRMEM_CST if there's an explicit cast; that
6347 cast should make the expression an invalid template argument. */
6348 if (TREE_CODE (pfn) != PTRMEM_CST)
6350 if (same_type_p (to_type, pfn_type))
6352 else if (integer_zerop (n))
6353 return build_reinterpret_cast (to_type, pfn,
6354 tf_warning_or_error);
6357 if (TREE_SIDE_EFFECTS (pfn))
6358 pfn = save_expr (pfn);
6360 /* Obtain the function pointer and the current DELTA. */
6361 if (TREE_CODE (pfn) == PTRMEM_CST)
6362 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6365 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6366 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6369 /* Just adjust the DELTA field. */
6370 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6371 (TREE_TYPE (delta), ptrdiff_type_node));
6372 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6373 n = cp_build_binary_op (input_location,
6374 LSHIFT_EXPR, n, integer_one_node,
6375 tf_warning_or_error);
6376 delta = cp_build_binary_op (input_location,
6377 PLUS_EXPR, delta, n, tf_warning_or_error);
6378 return build_ptrmemfunc1 (to_type, delta, npfn);
6381 /* Handle null pointer to member function conversions. */
6382 if (integer_zerop (pfn))
6384 pfn = build_c_cast (type, integer_zero_node);
6385 return build_ptrmemfunc1 (to_type,
6390 if (type_unknown_p (pfn))
6391 return instantiate_type (type, pfn, tf_warning_or_error);
6393 fn = TREE_OPERAND (pfn, 0);
6394 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6395 /* In a template, we will have preserved the
6397 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6398 return make_ptrmem_cst (to_type, fn);
6401 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6404 ??? There is no consistency as to the types returned for the above
6405 values. Some code acts as if it were a sizetype and some as if it were
6406 integer_type_node. */
6409 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6411 tree type = TREE_TYPE (cst);
6412 tree fn = PTRMEM_CST_MEMBER (cst);
6413 tree ptr_class, fn_class;
6415 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6417 /* The class that the function belongs to. */
6418 fn_class = DECL_CONTEXT (fn);
6420 /* The class that we're creating a pointer to member of. */
6421 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6423 /* First, calculate the adjustment to the function's class. */
6424 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6427 if (!DECL_VIRTUAL_P (fn))
6428 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6431 /* If we're dealing with a virtual function, we have to adjust 'this'
6432 again, to point to the base which provides the vtable entry for
6433 fn; the call will do the opposite adjustment. */
6434 tree orig_class = DECL_CONTEXT (fn);
6435 tree binfo = binfo_or_else (orig_class, fn_class);
6436 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6437 *delta, BINFO_OFFSET (binfo));
6438 *delta = fold_if_not_in_template (*delta);
6440 /* We set PFN to the vtable offset at which the function can be
6441 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6442 case delta is shifted left, and then incremented). */
6443 *pfn = DECL_VINDEX (fn);
6444 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6445 TYPE_SIZE_UNIT (vtable_entry_type));
6446 *pfn = fold_if_not_in_template (*pfn);
6448 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6450 case ptrmemfunc_vbit_in_pfn:
6451 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6453 *pfn = fold_if_not_in_template (*pfn);
6456 case ptrmemfunc_vbit_in_delta:
6457 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6458 *delta, integer_one_node);
6459 *delta = fold_if_not_in_template (*delta);
6460 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6461 *delta, integer_one_node);
6462 *delta = fold_if_not_in_template (*delta);
6469 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6470 *pfn = fold_if_not_in_template (*pfn);
6474 /* Return an expression for PFN from the pointer-to-member function
6478 pfn_from_ptrmemfunc (tree t)
6480 if (TREE_CODE (t) == PTRMEM_CST)
6485 expand_ptrmemfunc_cst (t, &delta, &pfn);
6490 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6493 /* Return an expression for DELTA from the pointer-to-member function
6497 delta_from_ptrmemfunc (tree t)
6499 if (TREE_CODE (t) == PTRMEM_CST)
6504 expand_ptrmemfunc_cst (t, &delta, &pfn);
6509 return build_ptrmemfunc_access_expr (t, delta_identifier);
6512 /* Convert value RHS to type TYPE as preparation for an assignment to
6513 an lvalue of type TYPE. ERRTYPE is a string to use in error
6514 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6515 are doing the conversion in order to pass the PARMNUMth argument of
6519 convert_for_assignment (tree type, tree rhs,
6520 const char *errtype, tree fndecl, int parmnum,
6521 tsubst_flags_t complain)
6524 enum tree_code coder;
6526 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6527 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6528 rhs = TREE_OPERAND (rhs, 0);
6530 rhstype = TREE_TYPE (rhs);
6531 coder = TREE_CODE (rhstype);
6533 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6534 && vector_types_convertible_p (type, rhstype, true))
6535 return convert (type, rhs);
6537 if (rhs == error_mark_node || rhstype == error_mark_node)
6538 return error_mark_node;
6539 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6540 return error_mark_node;
6542 /* The RHS of an assignment cannot have void type. */
6543 if (coder == VOID_TYPE)
6545 if (complain & tf_error)
6546 error ("void value not ignored as it ought to be");
6547 return error_mark_node;
6550 /* Simplify the RHS if possible. */
6551 if (TREE_CODE (rhs) == CONST_DECL)
6552 rhs = DECL_INITIAL (rhs);
6554 if (c_dialect_objc ())
6557 tree rname = fndecl;
6559 if (!strcmp (errtype, "assignment"))
6561 else if (!strcmp (errtype, "initialization"))
6565 tree selector = objc_message_selector ();
6569 if (selector && parmno > 1)
6576 if (objc_compare_types (type, rhstype, parmno, rname))
6577 return convert (type, rhs);
6582 The expression is implicitly converted (clause _conv_) to the
6583 cv-unqualified type of the left operand.
6585 We allow bad conversions here because by the time we get to this point
6586 we are committed to doing the conversion. If we end up doing a bad
6587 conversion, convert_like will complain. */
6588 if (!can_convert_arg_bad (type, rhstype, rhs))
6590 /* When -Wno-pmf-conversions is use, we just silently allow
6591 conversions from pointers-to-members to plain pointers. If
6592 the conversion doesn't work, cp_convert will complain. */
6594 && TYPE_PTR_P (type)
6595 && TYPE_PTRMEMFUNC_P (rhstype))
6596 rhs = cp_convert (strip_top_quals (type), rhs);
6599 if (complain & tf_error)
6601 /* If the right-hand side has unknown type, then it is an
6602 overloaded function. Call instantiate_type to get error
6604 if (rhstype == unknown_type_node)
6605 instantiate_type (type, rhs, tf_warning_or_error);
6607 error ("cannot convert %qT to %qT for argument %qP to %qD",
6608 rhstype, type, parmnum, fndecl);
6610 error ("cannot convert %qT to %qT in %s", rhstype, type,
6613 return error_mark_node;
6616 if (warn_missing_format_attribute)
6618 const enum tree_code codel = TREE_CODE (type);
6619 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6621 && check_missing_format_attribute (type, rhstype)
6622 && (complain & tf_warning))
6623 warning (OPT_Wmissing_format_attribute,
6624 "%s might be a candidate for a format attribute",
6628 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6630 if (warn_parentheses
6631 && type == boolean_type_node
6632 && TREE_CODE (rhs) == MODIFY_EXPR
6633 && !TREE_NO_WARNING (rhs)
6634 && TREE_TYPE (rhs) != boolean_type_node
6635 && (complain & tf_warning))
6637 warning (OPT_Wparentheses,
6638 "suggest parentheses around assignment used as truth value");
6639 TREE_NO_WARNING (rhs) = 1;
6642 return perform_implicit_conversion (strip_top_quals (type), rhs, complain);
6645 /* Convert RHS to be of type TYPE.
6646 If EXP is nonzero, it is the target of the initialization.
6647 ERRTYPE is a string to use in error messages.
6649 Two major differences between the behavior of
6650 `convert_for_assignment' and `convert_for_initialization'
6651 are that references are bashed in the former, while
6652 copied in the latter, and aggregates are assigned in
6653 the former (operator=) while initialized in the
6656 If using constructor make sure no conversion operator exists, if one does
6657 exist, an ambiguity exists.
6659 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6662 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6663 const char *errtype, tree fndecl, int parmnum,
6664 tsubst_flags_t complain)
6666 enum tree_code codel = TREE_CODE (type);
6668 enum tree_code coder;
6670 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6671 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6672 if (TREE_CODE (rhs) == NOP_EXPR
6673 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6674 && codel != REFERENCE_TYPE)
6675 rhs = TREE_OPERAND (rhs, 0);
6677 if (type == error_mark_node
6678 || rhs == error_mark_node
6679 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6680 return error_mark_node;
6682 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6683 && TREE_CODE (type) != ARRAY_TYPE
6684 && (TREE_CODE (type) != REFERENCE_TYPE
6685 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6686 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6687 && (TREE_CODE (type) != REFERENCE_TYPE
6688 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6689 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6690 rhs = decay_conversion (rhs);
6692 rhstype = TREE_TYPE (rhs);
6693 coder = TREE_CODE (rhstype);
6695 if (coder == ERROR_MARK)
6696 return error_mark_node;
6698 /* We accept references to incomplete types, so we can
6699 return here before checking if RHS is of complete type. */
6701 if (codel == REFERENCE_TYPE)
6703 /* This should eventually happen in convert_arguments. */
6704 int savew = 0, savee = 0;
6707 savew = warningcount, savee = errorcount;
6708 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6712 if (warningcount > savew)
6713 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6714 else if (errorcount > savee)
6715 error ("in passing argument %P of %q+D", parmnum, fndecl);
6721 exp = require_complete_type (exp);
6722 if (exp == error_mark_node)
6723 return error_mark_node;
6725 rhstype = non_reference (rhstype);
6727 type = complete_type (type);
6729 if (MAYBE_CLASS_TYPE_P (type))
6730 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6732 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6736 /* If RETVAL is the address of, or a reference to, a local variable or
6737 temporary give an appropriate warning. */
6740 maybe_warn_about_returning_address_of_local (tree retval)
6742 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6743 tree whats_returned = retval;
6747 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6748 whats_returned = TREE_OPERAND (whats_returned, 1);
6749 else if (CONVERT_EXPR_P (whats_returned)
6750 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6751 whats_returned = TREE_OPERAND (whats_returned, 0);
6756 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6758 whats_returned = TREE_OPERAND (whats_returned, 0);
6760 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6762 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6763 || TREE_CODE (whats_returned) == TARGET_EXPR)
6765 warning (0, "returning reference to temporary");
6768 if (TREE_CODE (whats_returned) == VAR_DECL
6769 && DECL_NAME (whats_returned)
6770 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6772 warning (0, "reference to non-lvalue returned");
6777 while (TREE_CODE (whats_returned) == COMPONENT_REF
6778 || TREE_CODE (whats_returned) == ARRAY_REF)
6779 whats_returned = TREE_OPERAND (whats_returned, 0);
6781 if (DECL_P (whats_returned)
6782 && DECL_NAME (whats_returned)
6783 && DECL_FUNCTION_SCOPE_P (whats_returned)
6784 && !(TREE_STATIC (whats_returned)
6785 || TREE_PUBLIC (whats_returned)))
6787 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6788 warning (0, "reference to local variable %q+D returned",
6791 warning (0, "address of local variable %q+D returned",
6797 /* Check that returning RETVAL from the current function is valid.
6798 Return an expression explicitly showing all conversions required to
6799 change RETVAL into the function return type, and to assign it to
6800 the DECL_RESULT for the function. Set *NO_WARNING to true if
6801 code reaches end of non-void function warning shouldn't be issued
6802 on this RETURN_EXPR. */
6805 check_return_expr (tree retval, bool *no_warning)
6808 /* The type actually returned by the function, after any
6811 int fn_returns_value_p;
6812 bool named_return_value_okay_p;
6814 *no_warning = false;
6816 /* A `volatile' function is one that isn't supposed to return, ever.
6817 (This is a G++ extension, used to get better code for functions
6818 that call the `volatile' function.) */
6819 if (TREE_THIS_VOLATILE (current_function_decl))
6820 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6822 /* Check for various simple errors. */
6823 if (DECL_DESTRUCTOR_P (current_function_decl))
6826 error ("returning a value from a destructor");
6829 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6831 if (in_function_try_handler)
6832 /* If a return statement appears in a handler of the
6833 function-try-block of a constructor, the program is ill-formed. */
6834 error ("cannot return from a handler of a function-try-block of a constructor");
6836 /* You can't return a value from a constructor. */
6837 error ("returning a value from a constructor");
6841 if (processing_template_decl)
6843 current_function_returns_value = 1;
6844 if (check_for_bare_parameter_packs (retval))
6845 retval = error_mark_node;
6849 /* When no explicit return-value is given in a function with a named
6850 return value, the named return value is used. */
6851 result = DECL_RESULT (current_function_decl);
6852 valtype = TREE_TYPE (result);
6853 gcc_assert (valtype != NULL_TREE);
6854 fn_returns_value_p = !VOID_TYPE_P (valtype);
6855 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6858 /* Check for a return statement with no return value in a function
6859 that's supposed to return a value. */
6860 if (!retval && fn_returns_value_p)
6862 permerror (input_location, "return-statement with no value, in function returning %qT",
6864 /* Clear this, so finish_function won't say that we reach the
6865 end of a non-void function (which we don't, we gave a
6867 current_function_returns_null = 0;
6868 /* And signal caller that TREE_NO_WARNING should be set on the
6869 RETURN_EXPR to avoid control reaches end of non-void function
6870 warnings in tree-cfg.c. */
6873 /* Check for a return statement with a value in a function that
6874 isn't supposed to return a value. */
6875 else if (retval && !fn_returns_value_p)
6877 if (VOID_TYPE_P (TREE_TYPE (retval)))
6878 /* You can return a `void' value from a function of `void'
6879 type. In that case, we have to evaluate the expression for
6880 its side-effects. */
6881 finish_expr_stmt (retval);
6883 permerror (input_location, "return-statement with a value, in function "
6884 "returning 'void'");
6885 current_function_returns_null = 1;
6887 /* There's really no value to return, after all. */
6891 /* Remember that this function can sometimes return without a
6893 current_function_returns_null = 1;
6895 /* Remember that this function did return a value. */
6896 current_function_returns_value = 1;
6898 /* Check for erroneous operands -- but after giving ourselves a
6899 chance to provide an error about returning a value from a void
6901 if (error_operand_p (retval))
6903 current_function_return_value = error_mark_node;
6904 return error_mark_node;
6907 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6908 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6909 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6910 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6912 && retval && null_ptr_cst_p (retval))
6913 warning (0, "%<operator new%> must not return NULL unless it is "
6914 "declared %<throw()%> (or -fcheck-new is in effect)");
6916 /* Effective C++ rule 15. See also start_function. */
6918 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6922 /* The function return type must be a reference to the current
6924 if (TREE_CODE (valtype) == REFERENCE_TYPE
6925 && same_type_ignoring_top_level_qualifiers_p
6926 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6928 /* Returning '*this' is obviously OK. */
6929 if (retval == current_class_ref)
6931 /* If we are calling a function whose return type is the same of
6932 the current class reference, it is ok. */
6933 else if (TREE_CODE (retval) == INDIRECT_REF
6934 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6939 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6942 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6944 [...] For a function with a class return type, if the expression
6945 in the return statement is the name of a local object, and the cv-
6946 unqualified type of the local object is the same as the function
6947 return type, an implementation is permitted to omit creating the tem-
6948 porary object to hold the function return value [...]
6950 So, if this is a value-returning function that always returns the same
6951 local variable, remember it.
6953 It might be nice to be more flexible, and choose the first suitable
6954 variable even if the function sometimes returns something else, but
6955 then we run the risk of clobbering the variable we chose if the other
6956 returned expression uses the chosen variable somehow. And people expect
6957 this restriction, anyway. (jason 2000-11-19)
6959 See finish_function and finalize_nrv for the rest of this optimization. */
6961 named_return_value_okay_p =
6962 (retval != NULL_TREE
6963 /* Must be a local, automatic variable. */
6964 && TREE_CODE (retval) == VAR_DECL
6965 && DECL_CONTEXT (retval) == current_function_decl
6966 && ! TREE_STATIC (retval)
6967 && ! DECL_ANON_UNION_VAR_P (retval)
6968 && (DECL_ALIGN (retval)
6969 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6970 /* The cv-unqualified type of the returned value must be the
6971 same as the cv-unqualified return type of the
6973 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
6975 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
6976 /* And the returned value must be non-volatile. */
6977 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
6979 if (fn_returns_value_p && flag_elide_constructors)
6981 if (named_return_value_okay_p
6982 && (current_function_return_value == NULL_TREE
6983 || current_function_return_value == retval))
6984 current_function_return_value = retval;
6986 current_function_return_value = error_mark_node;
6989 /* We don't need to do any conversions when there's nothing being
6994 /* Do any required conversions. */
6995 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6996 /* No conversions are required. */
7000 /* The type the function is declared to return. */
7001 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7002 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7004 /* The functype's return type will have been set to void, if it
7005 was an incomplete type. Just treat this as 'return;' */
7006 if (VOID_TYPE_P (functype))
7007 return error_mark_node;
7009 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7010 treated as an rvalue for the purposes of overload resolution to
7011 favor move constructors over copy constructors. */
7012 if ((cxx_dialect != cxx98)
7013 && named_return_value_okay_p
7014 /* The variable must not have the `volatile' qualifier. */
7015 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7016 /* The return type must be a class type. */
7017 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7018 flags = flags | LOOKUP_PREFER_RVALUE;
7020 /* First convert the value to the function's return type, then
7021 to the type of return value's location to handle the
7022 case that functype is smaller than the valtype. */
7023 retval = convert_for_initialization
7024 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7025 tf_warning_or_error);
7026 retval = convert (valtype, retval);
7028 /* If the conversion failed, treat this just like `return;'. */
7029 if (retval == error_mark_node)
7031 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7032 else if (! cfun->returns_struct
7033 && TREE_CODE (retval) == TARGET_EXPR
7034 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7035 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7036 TREE_OPERAND (retval, 0));
7038 maybe_warn_about_returning_address_of_local (retval);
7041 /* Actually copy the value returned into the appropriate location. */
7042 if (retval && retval != result)
7043 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7049 /* Returns nonzero if the pointer-type FROM can be converted to the
7050 pointer-type TO via a qualification conversion. If CONSTP is -1,
7051 then we return nonzero if the pointers are similar, and the
7052 cv-qualification signature of FROM is a proper subset of that of TO.
7054 If CONSTP is positive, then all outer pointers have been
7058 comp_ptr_ttypes_real (tree to, tree from, int constp)
7060 bool to_more_cv_qualified = false;
7061 bool is_opaque_pointer = false;
7063 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7065 if (TREE_CODE (to) != TREE_CODE (from))
7068 if (TREE_CODE (from) == OFFSET_TYPE
7069 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7070 TYPE_OFFSET_BASETYPE (to)))
7073 /* Const and volatile mean something different for function types,
7074 so the usual checks are not appropriate. */
7075 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7077 /* In Objective-C++, some types may have been 'volatilized' by
7078 the compiler for EH; when comparing them here, the volatile
7079 qualification must be ignored. */
7080 bool objc_quals_match = objc_type_quals_match (to, from);
7082 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7085 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7089 to_more_cv_qualified = true;
7093 constp &= TYPE_READONLY (to);
7096 if (TREE_CODE (to) == VECTOR_TYPE)
7097 is_opaque_pointer = vector_targets_convertible_p (to, from);
7099 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7100 return ((constp >= 0 || to_more_cv_qualified)
7101 && (is_opaque_pointer
7102 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7106 /* When comparing, say, char ** to char const **, this function takes
7107 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7108 types to this function. */
7111 comp_ptr_ttypes (tree to, tree from)
7113 return comp_ptr_ttypes_real (to, from, 1);
7116 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7117 type or inheritance-related types, regardless of cv-quals. */
7120 ptr_reasonably_similar (const_tree to, const_tree from)
7122 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7124 /* Any target type is similar enough to void. */
7125 if (TREE_CODE (to) == VOID_TYPE
7126 || TREE_CODE (from) == VOID_TYPE)
7129 if (TREE_CODE (to) != TREE_CODE (from))
7132 if (TREE_CODE (from) == OFFSET_TYPE
7133 && comptypes (TYPE_OFFSET_BASETYPE (to),
7134 TYPE_OFFSET_BASETYPE (from),
7135 COMPARE_BASE | COMPARE_DERIVED))
7138 if (TREE_CODE (to) == VECTOR_TYPE
7139 && vector_types_convertible_p (to, from, false))
7142 if (TREE_CODE (to) == INTEGER_TYPE
7143 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7146 if (TREE_CODE (to) == FUNCTION_TYPE)
7149 if (TREE_CODE (to) != POINTER_TYPE)
7151 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7152 COMPARE_BASE | COMPARE_DERIVED);
7156 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7157 pointer-to-member types) are the same, ignoring cv-qualification at
7161 comp_ptr_ttypes_const (tree to, tree from)
7163 bool is_opaque_pointer = false;
7165 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7167 if (TREE_CODE (to) != TREE_CODE (from))
7170 if (TREE_CODE (from) == OFFSET_TYPE
7171 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7172 TYPE_OFFSET_BASETYPE (to)))
7175 if (TREE_CODE (to) == VECTOR_TYPE)
7176 is_opaque_pointer = vector_targets_convertible_p (to, from);
7178 if (TREE_CODE (to) != POINTER_TYPE)
7179 return (is_opaque_pointer
7180 || same_type_ignoring_top_level_qualifiers_p (to, from));
7184 /* Returns the type qualifiers for this type, including the qualifiers on the
7185 elements for an array type. */
7188 cp_type_quals (const_tree type)
7190 /* This CONST_CAST is okay because strip_array_types returns its
7191 argument unmodified and we assign it to a const_tree. */
7192 type = strip_array_types (CONST_CAST_TREE(type));
7193 if (type == error_mark_node)
7194 return TYPE_UNQUALIFIED;
7195 return TYPE_QUALS (type);
7198 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7202 cp_type_readonly (const_tree type)
7204 /* This CONST_CAST is okay because strip_array_types returns its
7205 argument unmodified and we assign it to a const_tree. */
7206 type = strip_array_types (CONST_CAST_TREE(type));
7207 return TYPE_READONLY (type);
7210 /* Returns nonzero if the TYPE contains a mutable member. */
7213 cp_has_mutable_p (const_tree type)
7215 /* This CONST_CAST is okay because strip_array_types returns its
7216 argument unmodified and we assign it to a const_tree. */
7217 type = strip_array_types (CONST_CAST_TREE(type));
7219 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7222 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7223 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7224 approximation. In particular, consider:
7227 struct S { int i; };
7228 const S s = { f(); }
7230 Here, we will make "s" as TREE_READONLY (because it is declared
7231 "const") -- only to reverse ourselves upon seeing that the
7232 initializer is non-constant. */
7235 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7237 tree type = TREE_TYPE (decl);
7239 if (type == error_mark_node)
7242 if (TREE_CODE (decl) == TYPE_DECL)
7245 if (TREE_CODE (type) == FUNCTION_TYPE
7246 && type_quals != TYPE_UNQUALIFIED)
7248 /* This was an error in C++98 (cv-qualifiers cannot be added to
7249 a function type), but DR 295 makes the code well-formed by
7250 dropping the extra qualifiers. */
7253 tree bad_type = build_qualified_type (type, type_quals);
7254 pedwarn (input_location, OPT_pedantic,
7255 "ignoring %qV qualifiers added to function type %qT",
7259 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7263 /* Avoid setting TREE_READONLY incorrectly. */
7264 if (/* If the object has a constructor, the constructor may modify
7266 TYPE_NEEDS_CONSTRUCTING (type)
7267 /* If the type isn't complete, we don't know yet if it will need
7269 || !COMPLETE_TYPE_P (type)
7270 /* If the type has a mutable component, that component might be
7272 || TYPE_HAS_MUTABLE_P (type))
7273 type_quals &= ~TYPE_QUAL_CONST;
7275 c_apply_type_quals_to_decl (type_quals, decl);
7278 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7279 exemplar types such that casting T1 to T2 is casting away constness
7280 if and only if there is no implicit conversion from T1 to T2. */
7283 casts_away_constness_r (tree *t1, tree *t2)
7288 /* [expr.const.cast]
7290 For multi-level pointer to members and multi-level mixed pointers
7291 and pointers to members (conv.qual), the "member" aspect of a
7292 pointer to member level is ignored when determining if a const
7293 cv-qualifier has been cast away. */
7294 /* [expr.const.cast]
7296 For two pointer types:
7298 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7299 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7302 casting from X1 to X2 casts away constness if, for a non-pointer
7303 type T there does not exist an implicit conversion (clause
7306 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7310 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7311 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7312 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7314 *t1 = cp_build_qualified_type (void_type_node,
7315 cp_type_quals (*t1));
7316 *t2 = cp_build_qualified_type (void_type_node,
7317 cp_type_quals (*t2));
7321 quals1 = cp_type_quals (*t1);
7322 quals2 = cp_type_quals (*t2);
7324 if (TYPE_PTRMEM_P (*t1))
7325 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7327 *t1 = TREE_TYPE (*t1);
7328 if (TYPE_PTRMEM_P (*t2))
7329 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7331 *t2 = TREE_TYPE (*t2);
7333 casts_away_constness_r (t1, t2);
7334 *t1 = build_pointer_type (*t1);
7335 *t2 = build_pointer_type (*t2);
7336 *t1 = cp_build_qualified_type (*t1, quals1);
7337 *t2 = cp_build_qualified_type (*t2, quals2);
7340 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7344 casts_away_constness (tree t1, tree t2)
7346 if (TREE_CODE (t2) == REFERENCE_TYPE)
7348 /* [expr.const.cast]
7350 Casting from an lvalue of type T1 to an lvalue of type T2
7351 using a reference cast casts away constness if a cast from an
7352 rvalue of type "pointer to T1" to the type "pointer to T2"
7353 casts away constness. */
7354 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7355 return casts_away_constness (build_pointer_type (t1),
7356 build_pointer_type (TREE_TYPE (t2)));
7359 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7360 /* [expr.const.cast]
7362 Casting from an rvalue of type "pointer to data member of X
7363 of type T1" to the type "pointer to data member of Y of type
7364 T2" casts away constness if a cast from an rvalue of type
7365 "pointer to T1" to the type "pointer to T2" casts away
7367 return casts_away_constness
7368 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7369 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7371 /* Casting away constness is only something that makes sense for
7372 pointer or reference types. */
7373 if (TREE_CODE (t1) != POINTER_TYPE
7374 || TREE_CODE (t2) != POINTER_TYPE)
7377 /* Top-level qualifiers don't matter. */
7378 t1 = TYPE_MAIN_VARIANT (t1);
7379 t2 = TYPE_MAIN_VARIANT (t2);
7380 casts_away_constness_r (&t1, &t2);
7381 if (!can_convert (t2, t1))
7387 /* If T is a REFERENCE_TYPE return the type to which T refers.
7388 Otherwise, return T itself. */
7391 non_reference (tree t)
7393 if (TREE_CODE (t) == REFERENCE_TYPE)
7399 /* Return nonzero if REF is an lvalue valid for this language;
7400 otherwise, print an error message and return zero. USE says
7401 how the lvalue is being used and so selects the error message. */
7404 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
7406 int win = lvalue_p (ref);
7408 if (!win && (complain & tf_error))