1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com) and
5 modified by Brendan Kehoe (brendan@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 2, 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 COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
25 /* High-level class interface. */
29 #include "coretypes.h"
38 #include "diagnostic.h"
43 /* The various kinds of conversion. */
45 typedef enum conversion_kind {
59 /* The rank of the conversion. Order of the enumerals matters; better
60 conversions should come earlier in the list. */
62 typedef enum conversion_rank {
73 /* An implicit conversion sequence, in the sense of [over.best.ics].
74 The first conversion to be performed is at the end of the chain.
75 That conversion is always a cr_identity conversion. */
77 typedef struct conversion conversion;
79 /* The kind of conversion represented by this step. */
81 /* The rank of this conversion. */
83 BOOL_BITFIELD user_conv_p : 1;
84 BOOL_BITFIELD ellipsis_p : 1;
85 BOOL_BITFIELD this_p : 1;
86 BOOL_BITFIELD bad_p : 1;
87 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
88 temporary should be created to hold the result of the
90 BOOL_BITFIELD need_temporary_p : 1;
91 /* If KIND is ck_identity or ck_base_conv, true to indicate that the
92 copy constructor must be accessible, even though it is not being
94 BOOL_BITFIELD check_copy_constructor_p : 1;
95 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
96 from a pointer-to-derived to pointer-to-base is being performed. */
97 BOOL_BITFIELD base_p : 1;
98 /* The type of the expression resulting from the conversion. */
101 /* The next conversion in the chain. Since the conversions are
102 arranged from outermost to innermost, the NEXT conversion will
103 actually be performed before this conversion. This variant is
104 used only when KIND is neither ck_identity nor ck_ambig. */
106 /* The expression at the beginning of the conversion chain. This
107 variant is used only if KIND is ck_identity or ck_ambig. */
110 /* The function candidate corresponding to this conversion
111 sequence. This field is only used if KIND is ck_user. */
112 struct z_candidate *cand;
115 #define CONVERSION_RANK(NODE) \
116 ((NODE)->bad_p ? cr_bad \
117 : (NODE)->ellipsis_p ? cr_ellipsis \
118 : (NODE)->user_conv_p ? cr_user \
121 static struct obstack conversion_obstack;
122 static bool conversion_obstack_initialized;
124 static struct z_candidate * tourney (struct z_candidate *);
125 static int equal_functions (tree, tree);
126 static int joust (struct z_candidate *, struct z_candidate *, bool);
127 static int compare_ics (conversion *, conversion *);
128 static tree build_over_call (struct z_candidate *, int);
129 static tree build_java_interface_fn_ref (tree, tree);
130 #define convert_like(CONV, EXPR) \
131 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
132 /*issue_conversion_warnings=*/true, \
134 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
135 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
136 /*issue_conversion_warnings=*/true, \
138 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
140 static void op_error (enum tree_code, enum tree_code, tree, tree,
142 static tree build_object_call (tree, tree);
143 static tree resolve_args (tree);
144 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
145 static void print_z_candidate (const char *, struct z_candidate *);
146 static void print_z_candidates (struct z_candidate *);
147 static tree build_this (tree);
148 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
149 static bool any_strictly_viable (struct z_candidate *);
150 static struct z_candidate *add_template_candidate
151 (struct z_candidate **, tree, tree, tree, tree, tree,
152 tree, tree, int, unification_kind_t);
153 static struct z_candidate *add_template_candidate_real
154 (struct z_candidate **, tree, tree, tree, tree, tree,
155 tree, tree, int, tree, unification_kind_t);
156 static struct z_candidate *add_template_conv_candidate
157 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
158 static void add_builtin_candidates
159 (struct z_candidate **, enum tree_code, enum tree_code,
161 static void add_builtin_candidate
162 (struct z_candidate **, enum tree_code, enum tree_code,
163 tree, tree, tree, tree *, tree *, int);
164 static bool is_complete (tree);
165 static void build_builtin_candidate
166 (struct z_candidate **, tree, tree, tree, tree *, tree *,
168 static struct z_candidate *add_conv_candidate
169 (struct z_candidate **, tree, tree, tree, tree, tree);
170 static struct z_candidate *add_function_candidate
171 (struct z_candidate **, tree, tree, tree, tree, tree, int);
172 static conversion *implicit_conversion (tree, tree, tree, bool, int);
173 static conversion *standard_conversion (tree, tree, tree, bool, int);
174 static conversion *reference_binding (tree, tree, tree, int);
175 static conversion *build_conv (conversion_kind, tree, conversion *);
176 static bool is_subseq (conversion *, conversion *);
177 static tree maybe_handle_ref_bind (conversion **);
178 static void maybe_handle_implicit_object (conversion **);
179 static struct z_candidate *add_candidate
180 (struct z_candidate **, tree, tree, size_t,
181 conversion **, tree, tree, int);
182 static tree source_type (conversion *);
183 static void add_warning (struct z_candidate *, struct z_candidate *);
184 static bool reference_related_p (tree, tree);
185 static bool reference_compatible_p (tree, tree);
186 static conversion *convert_class_to_reference (tree, tree, tree);
187 static conversion *direct_reference_binding (tree, conversion *);
188 static bool promoted_arithmetic_type_p (tree);
189 static conversion *conditional_conversion (tree, tree);
190 static char *name_as_c_string (tree, tree, bool *);
191 static tree call_builtin_trap (void);
192 static tree prep_operand (tree);
193 static void add_candidates (tree, tree, tree, bool, tree, tree,
194 int, struct z_candidate **);
195 static conversion *merge_conversion_sequences (conversion *, conversion *);
196 static bool magic_varargs_p (tree);
197 typedef void (*diagnostic_fn_t) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
198 static tree build_temp (tree, tree, int, diagnostic_fn_t *);
199 static void check_constructor_callable (tree, tree);
201 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
202 NAME can take many forms... */
205 check_dtor_name (tree basetype, tree name)
207 /* Just accept something we've already complained about. */
208 if (name == error_mark_node)
211 if (TREE_CODE (name) == TYPE_DECL)
212 name = TREE_TYPE (name);
213 else if (TYPE_P (name))
215 else if (TREE_CODE (name) == IDENTIFIER_NODE)
217 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
218 || (TREE_CODE (basetype) == ENUMERAL_TYPE
219 && name == TYPE_IDENTIFIER (basetype)))
222 name = get_type_value (name);
228 template <class T> struct S { ~S(); };
232 NAME will be a class template. */
233 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
239 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
242 /* We want the address of a function or method. We avoid creating a
243 pointer-to-member function. */
246 build_addr_func (tree function)
248 tree type = TREE_TYPE (function);
250 /* We have to do these by hand to avoid real pointer to member
252 if (TREE_CODE (type) == METHOD_TYPE)
254 if (TREE_CODE (function) == OFFSET_REF)
256 tree object = build_address (TREE_OPERAND (function, 0));
257 return get_member_function_from_ptrfunc (&object,
258 TREE_OPERAND (function, 1));
260 function = build_address (function);
263 function = decay_conversion (function);
268 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
269 POINTER_TYPE to those. Note, pointer to member function types
270 (TYPE_PTRMEMFUNC_P) must be handled by our callers. */
273 build_call (tree function, tree parms)
275 int is_constructor = 0;
282 function = build_addr_func (function);
284 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
286 sorry ("unable to call pointer to member function here");
287 return error_mark_node;
290 fntype = TREE_TYPE (TREE_TYPE (function));
291 result_type = TREE_TYPE (fntype);
293 if (TREE_CODE (function) == ADDR_EXPR
294 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
295 decl = TREE_OPERAND (function, 0);
299 /* We check both the decl and the type; a function may be known not to
300 throw without being declared throw(). */
301 nothrow = ((decl && TREE_NOTHROW (decl))
302 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
304 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
305 current_function_returns_abnormally = 1;
307 if (decl && TREE_DEPRECATED (decl))
308 warn_deprecated_use (decl);
309 require_complete_eh_spec_types (fntype, decl);
311 if (decl && DECL_CONSTRUCTOR_P (decl))
314 if (decl && ! TREE_USED (decl))
316 /* We invoke build_call directly for several library functions.
317 These may have been declared normally if we're building libgcc,
318 so we can't just check DECL_ARTIFICIAL. */
319 gcc_assert (DECL_ARTIFICIAL (decl)
320 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
325 /* Don't pass empty class objects by value. This is useful
326 for tags in STL, which are used to control overload resolution.
327 We don't need to handle other cases of copying empty classes. */
328 if (! decl || ! DECL_BUILT_IN (decl))
329 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
330 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
331 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
333 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
334 TREE_VALUE (tmp) = build2 (COMPOUND_EXPR, TREE_TYPE (t),
335 TREE_VALUE (tmp), t);
338 function = build3 (CALL_EXPR, result_type, function, parms, NULL_TREE);
339 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
340 TREE_NOTHROW (function) = nothrow;
345 /* Build something of the form ptr->method (args)
346 or object.method (args). This can also build
347 calls to constructors, and find friends.
349 Member functions always take their class variable
352 INSTANCE is a class instance.
354 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
356 PARMS help to figure out what that NAME really refers to.
358 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
359 down to the real instance type to use for access checking. We need this
360 information to get protected accesses correct.
362 FLAGS is the logical disjunction of zero or more LOOKUP_
363 flags. See cp-tree.h for more info.
365 If this is all OK, calls build_function_call with the resolved
368 This function must also handle being called to perform
369 initialization, promotion/coercion of arguments, and
370 instantiation of default parameters.
372 Note that NAME may refer to an instance variable name. If
373 `operator()()' is defined for the type of that field, then we return
376 /* New overloading code. */
378 typedef struct z_candidate z_candidate;
380 typedef struct candidate_warning candidate_warning;
381 struct candidate_warning {
383 candidate_warning *next;
387 /* The FUNCTION_DECL that will be called if this candidate is
388 selected by overload resolution. */
390 /* The arguments to use when calling this function. */
392 /* The implicit conversion sequences for each of the arguments to
395 /* The number of implicit conversion sequences. */
397 /* If FN is a user-defined conversion, the standard conversion
398 sequence from the type returned by FN to the desired destination
400 conversion *second_conv;
402 /* If FN is a member function, the binfo indicating the path used to
403 qualify the name of FN at the call site. This path is used to
404 determine whether or not FN is accessible if it is selected by
405 overload resolution. The DECL_CONTEXT of FN will always be a
406 (possibly improper) base of this binfo. */
408 /* If FN is a non-static member function, the binfo indicating the
409 subobject to which the `this' pointer should be converted if FN
410 is selected by overload resolution. The type pointed to the by
411 the `this' pointer must correspond to the most derived class
412 indicated by the CONVERSION_PATH. */
413 tree conversion_path;
415 candidate_warning *warnings;
419 /* Returns true iff T is a null pointer constant in the sense of
423 null_ptr_cst_p (tree t)
427 A null pointer constant is an integral constant expression
428 (_expr.const_) rvalue of integer type that evaluates to zero. */
429 t = integral_constant_value (t);
431 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
436 /* Returns nonzero if PARMLIST consists of only default parms and/or
440 sufficient_parms_p (tree parmlist)
442 for (; parmlist && parmlist != void_list_node;
443 parmlist = TREE_CHAIN (parmlist))
444 if (!TREE_PURPOSE (parmlist))
449 /* Allocate N bytes of memory from the conversion obstack. The memory
450 is zeroed before being returned. */
453 conversion_obstack_alloc (size_t n)
456 if (!conversion_obstack_initialized)
458 gcc_obstack_init (&conversion_obstack);
459 conversion_obstack_initialized = true;
461 p = obstack_alloc (&conversion_obstack, n);
466 /* Dynamically allocate a conversion. */
469 alloc_conversion (conversion_kind kind)
472 c = conversion_obstack_alloc (sizeof (conversion));
477 #ifdef ENABLE_CHECKING
479 /* Make sure that all memory on the conversion obstack has been
483 validate_conversion_obstack (void)
485 if (conversion_obstack_initialized)
486 gcc_assert ((obstack_next_free (&conversion_obstack)
487 == obstack_base (&conversion_obstack)));
490 #endif /* ENABLE_CHECKING */
492 /* Dynamically allocate an array of N conversions. */
495 alloc_conversions (size_t n)
497 return conversion_obstack_alloc (n * sizeof (conversion *));
501 build_conv (conversion_kind code, tree type, conversion *from)
504 conversion_rank rank = CONVERSION_RANK (from);
506 /* We can't use buildl1 here because CODE could be USER_CONV, which
507 takes two arguments. In that case, the caller is responsible for
508 filling in the second argument. */
509 t = alloc_conversion (code);
532 t->user_conv_p = (code == ck_user || from->user_conv_p);
533 t->bad_p = from->bad_p;
538 /* Build a representation of the identity conversion from EXPR to
539 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
542 build_identity_conv (tree type, tree expr)
546 c = alloc_conversion (ck_identity);
553 /* Converting from EXPR to TYPE was ambiguous in the sense that there
554 were multiple user-defined conversions to accomplish the job.
555 Build a conversion that indicates that ambiguity. */
558 build_ambiguous_conv (tree type, tree expr)
562 c = alloc_conversion (ck_ambig);
570 strip_top_quals (tree t)
572 if (TREE_CODE (t) == ARRAY_TYPE)
574 return cp_build_qualified_type (t, 0);
577 /* Returns the standard conversion path (see [conv]) from type FROM to type
578 TO, if any. For proper handling of null pointer constants, you must
579 also pass the expression EXPR to convert from. If C_CAST_P is true,
580 this conversion is coming from a C-style cast. */
583 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
586 enum tree_code fcode, tcode;
588 bool fromref = false;
590 to = non_reference (to);
591 if (TREE_CODE (from) == REFERENCE_TYPE)
594 from = TREE_TYPE (from);
596 to = strip_top_quals (to);
597 from = strip_top_quals (from);
599 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
600 && expr && type_unknown_p (expr))
602 expr = instantiate_type (to, expr, tf_conv);
603 if (expr == error_mark_node)
605 from = TREE_TYPE (expr);
608 fcode = TREE_CODE (from);
609 tcode = TREE_CODE (to);
611 conv = build_identity_conv (from, expr);
612 if (fcode == FUNCTION_TYPE)
614 from = build_pointer_type (from);
615 fcode = TREE_CODE (from);
616 conv = build_conv (ck_lvalue, from, conv);
618 else if (fcode == ARRAY_TYPE)
620 from = build_pointer_type (TREE_TYPE (from));
621 fcode = TREE_CODE (from);
622 conv = build_conv (ck_lvalue, from, conv);
624 else if (fromref || (expr && lvalue_p (expr)))
625 conv = build_conv (ck_rvalue, from, conv);
627 /* Allow conversion between `__complex__' data types. */
628 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
630 /* The standard conversion sequence to convert FROM to TO is
631 the standard conversion sequence to perform componentwise
633 conversion *part_conv = standard_conversion
634 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
638 conv = build_conv (part_conv->kind, to, conv);
639 conv->rank = part_conv->rank;
647 if (same_type_p (from, to))
650 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
651 && expr && null_ptr_cst_p (expr))
652 conv = build_conv (ck_std, to, conv);
653 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
654 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
656 /* For backwards brain damage compatibility, allow interconversion of
657 pointers and integers with a pedwarn. */
658 conv = build_conv (ck_std, to, conv);
661 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
663 /* For backwards brain damage compatibility, allow interconversion of
664 enums and integers with a pedwarn. */
665 conv = build_conv (ck_std, to, conv);
668 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
669 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
674 if (tcode == POINTER_TYPE
675 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
678 else if (VOID_TYPE_P (TREE_TYPE (to))
679 && !TYPE_PTRMEM_P (from)
680 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
682 from = build_pointer_type
683 (cp_build_qualified_type (void_type_node,
684 cp_type_quals (TREE_TYPE (from))));
685 conv = build_conv (ck_ptr, from, conv);
687 else if (TYPE_PTRMEM_P (from))
689 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
690 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
692 if (DERIVED_FROM_P (fbase, tbase)
693 && (same_type_ignoring_top_level_qualifiers_p
694 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
695 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
697 from = build_ptrmem_type (tbase,
698 TYPE_PTRMEM_POINTED_TO_TYPE (from));
699 conv = build_conv (ck_pmem, from, conv);
701 else if (!same_type_p (fbase, tbase))
704 else if (IS_AGGR_TYPE (TREE_TYPE (from))
705 && IS_AGGR_TYPE (TREE_TYPE (to))
708 An rvalue of type "pointer to cv D," where D is a
709 class type, can be converted to an rvalue of type
710 "pointer to cv B," where B is a base class (clause
711 _class.derived_) of D. If B is an inaccessible
712 (clause _class.access_) or ambiguous
713 (_class.member.lookup_) base class of D, a program
714 that necessitates this conversion is ill-formed.
715 Therefore, we use DERIVED_FROM_P, and do not check
716 access or uniqueness. */
717 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
720 cp_build_qualified_type (TREE_TYPE (to),
721 cp_type_quals (TREE_TYPE (from)));
722 from = build_pointer_type (from);
723 conv = build_conv (ck_ptr, from, conv);
727 if (tcode == POINTER_TYPE)
729 to_pointee = TREE_TYPE (to);
730 from_pointee = TREE_TYPE (from);
734 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
735 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
738 if (same_type_p (from, to))
740 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
741 /* In a C-style cast, we ignore CV-qualification because we
742 are allowed to perform a static_cast followed by a
744 conv = build_conv (ck_qual, to, conv);
745 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
746 conv = build_conv (ck_qual, to, conv);
747 else if (expr && string_conv_p (to, expr, 0))
748 /* converting from string constant to char *. */
749 conv = build_conv (ck_qual, to, conv);
750 else if (ptr_reasonably_similar (to_pointee, from_pointee))
752 conv = build_conv (ck_ptr, to, conv);
760 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
762 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
763 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
764 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
765 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
767 if (!DERIVED_FROM_P (fbase, tbase)
768 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
769 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
770 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
771 || cp_type_quals (fbase) != cp_type_quals (tbase))
774 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
775 from = build_method_type_directly (from,
777 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
778 from = build_ptrmemfunc_type (build_pointer_type (from));
779 conv = build_conv (ck_pmem, from, conv);
782 else if (tcode == BOOLEAN_TYPE)
786 An rvalue of arithmetic, enumeration, pointer, or pointer to
787 member type can be converted to an rvalue of type bool. */
788 if (ARITHMETIC_TYPE_P (from)
789 || fcode == ENUMERAL_TYPE
790 || fcode == POINTER_TYPE
791 || TYPE_PTR_TO_MEMBER_P (from))
793 conv = build_conv (ck_std, to, conv);
794 if (fcode == POINTER_TYPE
795 || TYPE_PTRMEM_P (from)
796 || (TYPE_PTRMEMFUNC_P (from)
797 && conv->rank < cr_pbool))
798 conv->rank = cr_pbool;
804 /* We don't check for ENUMERAL_TYPE here because there are no standard
805 conversions to enum type. */
806 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
807 || tcode == REAL_TYPE)
809 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
811 conv = build_conv (ck_std, to, conv);
813 /* Give this a better rank if it's a promotion. */
814 if (same_type_p (to, type_promotes_to (from))
815 && conv->u.next->rank <= cr_promotion)
816 conv->rank = cr_promotion;
818 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
819 && vector_types_convertible_p (from, to))
820 return build_conv (ck_std, to, conv);
821 else if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE)
822 && IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
823 && is_properly_derived_from (from, to))
825 if (conv->kind == ck_rvalue)
827 conv = build_conv (ck_base, to, conv);
828 /* The derived-to-base conversion indicates the initialization
829 of a parameter with base type from an object of a derived
830 type. A temporary object is created to hold the result of
832 conv->need_temporary_p = true;
840 /* Returns nonzero if T1 is reference-related to T2. */
843 reference_related_p (tree t1, tree t2)
845 t1 = TYPE_MAIN_VARIANT (t1);
846 t2 = TYPE_MAIN_VARIANT (t2);
850 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
851 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
853 return (same_type_p (t1, t2)
854 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
855 && DERIVED_FROM_P (t1, t2)));
858 /* Returns nonzero if T1 is reference-compatible with T2. */
861 reference_compatible_p (tree t1, tree t2)
865 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
866 reference-related to T2 and cv1 is the same cv-qualification as,
867 or greater cv-qualification than, cv2. */
868 return (reference_related_p (t1, t2)
869 && at_least_as_qualified_p (t1, t2));
872 /* Determine whether or not the EXPR (of class type S) can be
873 converted to T as in [over.match.ref]. */
876 convert_class_to_reference (tree t, tree s, tree expr)
882 struct z_candidate *candidates;
883 struct z_candidate *cand;
886 conversions = lookup_conversions (s);
892 Assuming that "cv1 T" is the underlying type of the reference
893 being initialized, and "cv S" is the type of the initializer
894 expression, with S a class type, the candidate functions are
897 --The conversion functions of S and its base classes are
898 considered. Those that are not hidden within S and yield type
899 "reference to cv2 T2", where "cv1 T" is reference-compatible
900 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
902 The argument list has one argument, which is the initializer
907 /* Conceptually, we should take the address of EXPR and put it in
908 the argument list. Unfortunately, however, that can result in
909 error messages, which we should not issue now because we are just
910 trying to find a conversion operator. Therefore, we use NULL,
911 cast to the appropriate type. */
912 arglist = build_int_cst (build_pointer_type (s), 0);
913 arglist = build_tree_list (NULL_TREE, arglist);
915 reference_type = build_reference_type (t);
919 tree fns = TREE_VALUE (conversions);
921 for (; fns; fns = OVL_NEXT (fns))
923 tree f = OVL_CURRENT (fns);
924 tree t2 = TREE_TYPE (TREE_TYPE (f));
928 /* If this is a template function, try to get an exact
930 if (TREE_CODE (f) == TEMPLATE_DECL)
932 cand = add_template_candidate (&candidates,
938 TREE_PURPOSE (conversions),
944 /* Now, see if the conversion function really returns
945 an lvalue of the appropriate type. From the
946 point of view of unification, simply returning an
947 rvalue of the right type is good enough. */
949 t2 = TREE_TYPE (TREE_TYPE (f));
950 if (TREE_CODE (t2) != REFERENCE_TYPE
951 || !reference_compatible_p (t, TREE_TYPE (t2)))
953 candidates = candidates->next;
958 else if (TREE_CODE (t2) == REFERENCE_TYPE
959 && reference_compatible_p (t, TREE_TYPE (t2)))
960 cand = add_function_candidate (&candidates, f, s, arglist,
962 TREE_PURPOSE (conversions),
967 conversion *identity_conv;
968 /* Build a standard conversion sequence indicating the
969 binding from the reference type returned by the
970 function to the desired REFERENCE_TYPE. */
972 = build_identity_conv (TREE_TYPE (TREE_TYPE
973 (TREE_TYPE (cand->fn))),
976 = (direct_reference_binding
977 (reference_type, identity_conv));
978 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
981 conversions = TREE_CHAIN (conversions);
984 candidates = splice_viable (candidates, pedantic, &any_viable_p);
985 /* If none of the conversion functions worked out, let our caller
990 cand = tourney (candidates);
994 /* Now that we know that this is the function we're going to use fix
995 the dummy first argument. */
996 cand->args = tree_cons (NULL_TREE,
998 TREE_CHAIN (cand->args));
1000 /* Build a user-defined conversion sequence representing the
1002 conv = build_conv (ck_user,
1003 TREE_TYPE (TREE_TYPE (cand->fn)),
1004 build_identity_conv (TREE_TYPE (expr), expr));
1007 /* Merge it with the standard conversion sequence from the
1008 conversion function's return type to the desired type. */
1009 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1011 if (cand->viable == -1)
1014 return cand->second_conv;
1017 /* A reference of the indicated TYPE is being bound directly to the
1018 expression represented by the implicit conversion sequence CONV.
1019 Return a conversion sequence for this binding. */
1022 direct_reference_binding (tree type, conversion *conv)
1026 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1027 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1029 t = TREE_TYPE (type);
1033 When a parameter of reference type binds directly
1034 (_dcl.init.ref_) to an argument expression, the implicit
1035 conversion sequence is the identity conversion, unless the
1036 argument expression has a type that is a derived class of the
1037 parameter type, in which case the implicit conversion sequence is
1038 a derived-to-base Conversion.
1040 If the parameter binds directly to the result of applying a
1041 conversion function to the argument expression, the implicit
1042 conversion sequence is a user-defined conversion sequence
1043 (_over.ics.user_), with the second standard conversion sequence
1044 either an identity conversion or, if the conversion function
1045 returns an entity of a type that is a derived class of the
1046 parameter type, a derived-to-base conversion. */
1047 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1049 /* Represent the derived-to-base conversion. */
1050 conv = build_conv (ck_base, t, conv);
1051 /* We will actually be binding to the base-class subobject in
1052 the derived class, so we mark this conversion appropriately.
1053 That way, convert_like knows not to generate a temporary. */
1054 conv->need_temporary_p = false;
1056 return build_conv (ck_ref_bind, type, conv);
1059 /* Returns the conversion path from type FROM to reference type TO for
1060 purposes of reference binding. For lvalue binding, either pass a
1061 reference type to FROM or an lvalue expression to EXPR. If the
1062 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1063 the conversion returned. */
1066 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1068 conversion *conv = NULL;
1069 tree to = TREE_TYPE (rto);
1073 cp_lvalue_kind lvalue_p = clk_none;
1075 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1077 expr = instantiate_type (to, expr, tf_none);
1078 if (expr == error_mark_node)
1080 from = TREE_TYPE (expr);
1083 if (TREE_CODE (from) == REFERENCE_TYPE)
1085 /* Anything with reference type is an lvalue. */
1086 lvalue_p = clk_ordinary;
1087 from = TREE_TYPE (from);
1090 lvalue_p = real_lvalue_p (expr);
1092 /* Figure out whether or not the types are reference-related and
1093 reference compatible. We have do do this after stripping
1094 references from FROM. */
1095 related_p = reference_related_p (to, from);
1096 compatible_p = reference_compatible_p (to, from);
1098 if (lvalue_p && compatible_p)
1102 If the initializer expression
1104 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1105 is reference-compatible with "cv2 T2,"
1107 the reference is bound directly to the initializer expression
1109 conv = build_identity_conv (from, expr);
1110 conv = direct_reference_binding (rto, conv);
1111 if ((lvalue_p & clk_bitfield) != 0
1112 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1113 /* For the purposes of overload resolution, we ignore the fact
1114 this expression is a bitfield or packed field. (In particular,
1115 [over.ics.ref] says specifically that a function with a
1116 non-const reference parameter is viable even if the
1117 argument is a bitfield.)
1119 However, when we actually call the function we must create
1120 a temporary to which to bind the reference. If the
1121 reference is volatile, or isn't const, then we cannot make
1122 a temporary, so we just issue an error when the conversion
1124 conv->need_temporary_p = true;
1128 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1132 If the initializer expression
1134 -- has a class type (i.e., T2 is a class type) can be
1135 implicitly converted to an lvalue of type "cv3 T3," where
1136 "cv1 T1" is reference-compatible with "cv3 T3". (this
1137 conversion is selected by enumerating the applicable
1138 conversion functions (_over.match.ref_) and choosing the
1139 best one through overload resolution. (_over.match_).
1141 the reference is bound to the lvalue result of the conversion
1142 in the second case. */
1143 conv = convert_class_to_reference (to, from, expr);
1148 /* From this point on, we conceptually need temporaries, even if we
1149 elide them. Only the cases above are "direct bindings". */
1150 if (flags & LOOKUP_NO_TEMP_BIND)
1155 When a parameter of reference type is not bound directly to an
1156 argument expression, the conversion sequence is the one required
1157 to convert the argument expression to the underlying type of the
1158 reference according to _over.best.ics_. Conceptually, this
1159 conversion sequence corresponds to copy-initializing a temporary
1160 of the underlying type with the argument expression. Any
1161 difference in top-level cv-qualification is subsumed by the
1162 initialization itself and does not constitute a conversion. */
1166 Otherwise, the reference shall be to a non-volatile const type. */
1167 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1172 If the initializer expression is an rvalue, with T2 a class type,
1173 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1174 is bound in one of the following ways:
1176 -- The reference is bound to the object represented by the rvalue
1177 or to a sub-object within that object.
1181 We use the first alternative. The implicit conversion sequence
1182 is supposed to be same as we would obtain by generating a
1183 temporary. Fortunately, if the types are reference compatible,
1184 then this is either an identity conversion or the derived-to-base
1185 conversion, just as for direct binding. */
1186 if (CLASS_TYPE_P (from) && compatible_p)
1188 conv = build_identity_conv (from, expr);
1189 conv = direct_reference_binding (rto, conv);
1190 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1191 conv->u.next->check_copy_constructor_p = true;
1197 Otherwise, a temporary of type "cv1 T1" is created and
1198 initialized from the initializer expression using the rules for a
1199 non-reference copy initialization. If T1 is reference-related to
1200 T2, cv1 must be the same cv-qualification as, or greater
1201 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1202 if (related_p && !at_least_as_qualified_p (to, from))
1205 conv = implicit_conversion (to, from, expr, /*c_cast_p=*/false,
1210 conv = build_conv (ck_ref_bind, rto, conv);
1211 /* This reference binding, unlike those above, requires the
1212 creation of a temporary. */
1213 conv->need_temporary_p = true;
1218 /* Returns the implicit conversion sequence (see [over.ics]) from type
1219 FROM to type TO. The optional expression EXPR may affect the
1220 conversion. FLAGS are the usual overloading flags. Only
1221 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1222 conversion is coming from a C-style cast. */
1225 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1230 if (from == error_mark_node || to == error_mark_node
1231 || expr == error_mark_node)
1234 if (TREE_CODE (to) == REFERENCE_TYPE)
1235 conv = reference_binding (to, from, expr, flags);
1237 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1242 if (expr != NULL_TREE
1243 && (IS_AGGR_TYPE (from)
1244 || IS_AGGR_TYPE (to))
1245 && (flags & LOOKUP_NO_CONVERSION) == 0)
1247 struct z_candidate *cand;
1249 cand = build_user_type_conversion_1
1250 (to, expr, LOOKUP_ONLYCONVERTING);
1252 conv = cand->second_conv;
1254 /* We used to try to bind a reference to a temporary here, but that
1255 is now handled by the recursive call to this function at the end
1256 of reference_binding. */
1263 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1266 static struct z_candidate *
1267 add_candidate (struct z_candidate **candidates,
1269 size_t num_convs, conversion **convs,
1270 tree access_path, tree conversion_path,
1273 struct z_candidate *cand
1274 = conversion_obstack_alloc (sizeof (struct z_candidate));
1278 cand->convs = convs;
1279 cand->num_convs = num_convs;
1280 cand->access_path = access_path;
1281 cand->conversion_path = conversion_path;
1282 cand->viable = viable;
1283 cand->next = *candidates;
1289 /* Create an overload candidate for the function or method FN called with
1290 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1291 to implicit_conversion.
1293 CTYPE, if non-NULL, is the type we want to pretend this function
1294 comes from for purposes of overload resolution. */
1296 static struct z_candidate *
1297 add_function_candidate (struct z_candidate **candidates,
1298 tree fn, tree ctype, tree arglist,
1299 tree access_path, tree conversion_path,
1302 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1305 tree parmnode, argnode;
1309 /* At this point we should not see any functions which haven't been
1310 explicitly declared, except for friend functions which will have
1311 been found using argument dependent lookup. */
1312 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1314 /* The `this', `in_chrg' and VTT arguments to constructors are not
1315 considered in overload resolution. */
1316 if (DECL_CONSTRUCTOR_P (fn))
1318 parmlist = skip_artificial_parms_for (fn, parmlist);
1319 orig_arglist = arglist;
1320 arglist = skip_artificial_parms_for (fn, arglist);
1323 orig_arglist = arglist;
1325 len = list_length (arglist);
1326 convs = alloc_conversions (len);
1328 /* 13.3.2 - Viable functions [over.match.viable]
1329 First, to be a viable function, a candidate function shall have enough
1330 parameters to agree in number with the arguments in the list.
1332 We need to check this first; otherwise, checking the ICSes might cause
1333 us to produce an ill-formed template instantiation. */
1335 parmnode = parmlist;
1336 for (i = 0; i < len; ++i)
1338 if (parmnode == NULL_TREE || parmnode == void_list_node)
1340 parmnode = TREE_CHAIN (parmnode);
1343 if (i < len && parmnode)
1346 /* Make sure there are default args for the rest of the parms. */
1347 else if (!sufficient_parms_p (parmnode))
1353 /* Second, for F to be a viable function, there shall exist for each
1354 argument an implicit conversion sequence that converts that argument
1355 to the corresponding parameter of F. */
1357 parmnode = parmlist;
1360 for (i = 0; i < len; ++i)
1362 tree arg = TREE_VALUE (argnode);
1363 tree argtype = lvalue_type (arg);
1367 if (parmnode == void_list_node)
1370 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1371 && ! DECL_CONSTRUCTOR_P (fn));
1375 tree parmtype = TREE_VALUE (parmnode);
1377 /* The type of the implicit object parameter ('this') for
1378 overload resolution is not always the same as for the
1379 function itself; conversion functions are considered to
1380 be members of the class being converted, and functions
1381 introduced by a using-declaration are considered to be
1382 members of the class that uses them.
1384 Since build_over_call ignores the ICS for the `this'
1385 parameter, we can just change the parm type. */
1386 if (ctype && is_this)
1389 = build_qualified_type (ctype,
1390 TYPE_QUALS (TREE_TYPE (parmtype)));
1391 parmtype = build_pointer_type (parmtype);
1394 t = implicit_conversion (parmtype, argtype, arg,
1395 /*c_cast_p=*/false, flags);
1399 t = build_identity_conv (argtype, arg);
1400 t->ellipsis_p = true;
1417 parmnode = TREE_CHAIN (parmnode);
1418 argnode = TREE_CHAIN (argnode);
1422 return add_candidate (candidates, fn, orig_arglist, len, convs,
1423 access_path, conversion_path, viable);
1426 /* Create an overload candidate for the conversion function FN which will
1427 be invoked for expression OBJ, producing a pointer-to-function which
1428 will in turn be called with the argument list ARGLIST, and add it to
1429 CANDIDATES. FLAGS is passed on to implicit_conversion.
1431 Actually, we don't really care about FN; we care about the type it
1432 converts to. There may be multiple conversion functions that will
1433 convert to that type, and we rely on build_user_type_conversion_1 to
1434 choose the best one; so when we create our candidate, we record the type
1435 instead of the function. */
1437 static struct z_candidate *
1438 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1439 tree arglist, tree access_path, tree conversion_path)
1441 tree totype = TREE_TYPE (TREE_TYPE (fn));
1442 int i, len, viable, flags;
1443 tree parmlist, parmnode, argnode;
1446 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1447 parmlist = TREE_TYPE (parmlist);
1448 parmlist = TYPE_ARG_TYPES (parmlist);
1450 len = list_length (arglist) + 1;
1451 convs = alloc_conversions (len);
1452 parmnode = parmlist;
1455 flags = LOOKUP_NORMAL;
1457 /* Don't bother looking up the same type twice. */
1458 if (*candidates && (*candidates)->fn == totype)
1461 for (i = 0; i < len; ++i)
1463 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1464 tree argtype = lvalue_type (arg);
1468 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1470 else if (parmnode == void_list_node)
1473 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1474 /*c_cast_p=*/false, flags);
1477 t = build_identity_conv (argtype, arg);
1478 t->ellipsis_p = true;
1492 parmnode = TREE_CHAIN (parmnode);
1493 argnode = TREE_CHAIN (argnode);
1499 if (!sufficient_parms_p (parmnode))
1502 return add_candidate (candidates, totype, arglist, len, convs,
1503 access_path, conversion_path, viable);
1507 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1508 tree type1, tree type2, tree *args, tree *argtypes,
1520 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1521 convs = alloc_conversions (num_convs);
1523 for (i = 0; i < 2; ++i)
1528 t = implicit_conversion (types[i], argtypes[i], args[i],
1529 /*c_cast_p=*/false, flags);
1533 /* We need something for printing the candidate. */
1534 t = build_identity_conv (types[i], NULL_TREE);
1541 /* For COND_EXPR we rearranged the arguments; undo that now. */
1544 convs[2] = convs[1];
1545 convs[1] = convs[0];
1546 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1547 /*c_cast_p=*/false, flags);
1554 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1556 /*access_path=*/NULL_TREE,
1557 /*conversion_path=*/NULL_TREE,
1562 is_complete (tree t)
1564 return COMPLETE_TYPE_P (complete_type (t));
1567 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1570 promoted_arithmetic_type_p (tree type)
1574 In this section, the term promoted integral type is used to refer
1575 to those integral types which are preserved by integral promotion
1576 (including e.g. int and long but excluding e.g. char).
1577 Similarly, the term promoted arithmetic type refers to promoted
1578 integral types plus floating types. */
1579 return ((INTEGRAL_TYPE_P (type)
1580 && same_type_p (type_promotes_to (type), type))
1581 || TREE_CODE (type) == REAL_TYPE);
1584 /* Create any builtin operator overload candidates for the operator in
1585 question given the converted operand types TYPE1 and TYPE2. The other
1586 args are passed through from add_builtin_candidates to
1587 build_builtin_candidate.
1589 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1590 If CODE is requires candidates operands of the same type of the kind
1591 of which TYPE1 and TYPE2 are, we add both candidates
1592 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1595 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1596 enum tree_code code2, tree fnname, tree type1,
1597 tree type2, tree *args, tree *argtypes, int flags)
1601 case POSTINCREMENT_EXPR:
1602 case POSTDECREMENT_EXPR:
1603 args[1] = integer_zero_node;
1604 type2 = integer_type_node;
1613 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1614 and VQ is either volatile or empty, there exist candidate operator
1615 functions of the form
1616 VQ T& operator++(VQ T&);
1617 T operator++(VQ T&, int);
1618 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1619 type other than bool, and VQ is either volatile or empty, there exist
1620 candidate operator functions of the form
1621 VQ T& operator--(VQ T&);
1622 T operator--(VQ T&, int);
1623 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1624 complete object type, and VQ is either volatile or empty, there exist
1625 candidate operator functions of the form
1626 T*VQ& operator++(T*VQ&);
1627 T*VQ& operator--(T*VQ&);
1628 T* operator++(T*VQ&, int);
1629 T* operator--(T*VQ&, int); */
1631 case POSTDECREMENT_EXPR:
1632 case PREDECREMENT_EXPR:
1633 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1635 case POSTINCREMENT_EXPR:
1636 case PREINCREMENT_EXPR:
1637 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1639 type1 = build_reference_type (type1);
1644 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1645 exist candidate operator functions of the form
1649 8 For every function type T, there exist candidate operator functions of
1651 T& operator*(T*); */
1654 if (TREE_CODE (type1) == POINTER_TYPE
1655 && (TYPE_PTROB_P (type1)
1656 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1660 /* 9 For every type T, there exist candidate operator functions of the form
1663 10For every promoted arithmetic type T, there exist candidate operator
1664 functions of the form
1668 case UNARY_PLUS_EXPR: /* unary + */
1669 if (TREE_CODE (type1) == POINTER_TYPE)
1672 if (ARITHMETIC_TYPE_P (type1))
1676 /* 11For every promoted integral type T, there exist candidate operator
1677 functions of the form
1681 if (INTEGRAL_TYPE_P (type1))
1685 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1686 is the same type as C2 or is a derived class of C2, T is a complete
1687 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1688 there exist candidate operator functions of the form
1689 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1690 where CV12 is the union of CV1 and CV2. */
1693 if (TREE_CODE (type1) == POINTER_TYPE
1694 && TYPE_PTR_TO_MEMBER_P (type2))
1696 tree c1 = TREE_TYPE (type1);
1697 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1699 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1700 && (TYPE_PTRMEMFUNC_P (type2)
1701 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1706 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1707 didate operator functions of the form
1712 bool operator<(L, R);
1713 bool operator>(L, R);
1714 bool operator<=(L, R);
1715 bool operator>=(L, R);
1716 bool operator==(L, R);
1717 bool operator!=(L, R);
1718 where LR is the result of the usual arithmetic conversions between
1721 14For every pair of types T and I, where T is a cv-qualified or cv-
1722 unqualified complete object type and I is a promoted integral type,
1723 there exist candidate operator functions of the form
1724 T* operator+(T*, I);
1725 T& operator[](T*, I);
1726 T* operator-(T*, I);
1727 T* operator+(I, T*);
1728 T& operator[](I, T*);
1730 15For every T, where T is a pointer to complete object type, there exist
1731 candidate operator functions of the form112)
1732 ptrdiff_t operator-(T, T);
1734 16For every pointer or enumeration type T, there exist candidate operator
1735 functions of the form
1736 bool operator<(T, T);
1737 bool operator>(T, T);
1738 bool operator<=(T, T);
1739 bool operator>=(T, T);
1740 bool operator==(T, T);
1741 bool operator!=(T, T);
1743 17For every pointer to member type T, there exist candidate operator
1744 functions of the form
1745 bool operator==(T, T);
1746 bool operator!=(T, T); */
1749 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1751 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1753 type2 = ptrdiff_type_node;
1757 case TRUNC_DIV_EXPR:
1758 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1764 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1765 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1767 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1772 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1784 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1786 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1788 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1790 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1795 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1803 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1806 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1808 type1 = ptrdiff_type_node;
1811 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1813 type2 = ptrdiff_type_node;
1818 /* 18For every pair of promoted integral types L and R, there exist candi-
1819 date operator functions of the form
1826 where LR is the result of the usual arithmetic conversions between
1829 case TRUNC_MOD_EXPR:
1835 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1839 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1840 type, VQ is either volatile or empty, and R is a promoted arithmetic
1841 type, there exist candidate operator functions of the form
1842 VQ L& operator=(VQ L&, R);
1843 VQ L& operator*=(VQ L&, R);
1844 VQ L& operator/=(VQ L&, R);
1845 VQ L& operator+=(VQ L&, R);
1846 VQ L& operator-=(VQ L&, R);
1848 20For every pair T, VQ), where T is any type and VQ is either volatile
1849 or empty, there exist candidate operator functions of the form
1850 T*VQ& operator=(T*VQ&, T*);
1852 21For every pair T, VQ), where T is a pointer to member type and VQ is
1853 either volatile or empty, there exist candidate operator functions of
1855 VQ T& operator=(VQ T&, T);
1857 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1858 unqualified complete object type, VQ is either volatile or empty, and
1859 I is a promoted integral type, there exist candidate operator func-
1861 T*VQ& operator+=(T*VQ&, I);
1862 T*VQ& operator-=(T*VQ&, I);
1864 23For every triple L, VQ, R), where L is an integral or enumeration
1865 type, VQ is either volatile or empty, and R is a promoted integral
1866 type, there exist candidate operator functions of the form
1868 VQ L& operator%=(VQ L&, R);
1869 VQ L& operator<<=(VQ L&, R);
1870 VQ L& operator>>=(VQ L&, R);
1871 VQ L& operator&=(VQ L&, R);
1872 VQ L& operator^=(VQ L&, R);
1873 VQ L& operator|=(VQ L&, R); */
1880 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1882 type2 = ptrdiff_type_node;
1886 case TRUNC_DIV_EXPR:
1887 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1891 case TRUNC_MOD_EXPR:
1897 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1902 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1904 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1905 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1906 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1907 || ((TYPE_PTRMEMFUNC_P (type1)
1908 || TREE_CODE (type1) == POINTER_TYPE)
1909 && null_ptr_cst_p (args[1])))
1919 type1 = build_reference_type (type1);
1925 For every pair of promoted arithmetic types L and R, there
1926 exist candidate operator functions of the form
1928 LR operator?(bool, L, R);
1930 where LR is the result of the usual arithmetic conversions
1931 between types L and R.
1933 For every type T, where T is a pointer or pointer-to-member
1934 type, there exist candidate operator functions of the form T
1935 operator?(bool, T, T); */
1937 if (promoted_arithmetic_type_p (type1)
1938 && promoted_arithmetic_type_p (type2))
1942 /* Otherwise, the types should be pointers. */
1943 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
1944 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
1947 /* We don't check that the two types are the same; the logic
1948 below will actually create two candidates; one in which both
1949 parameter types are TYPE1, and one in which both parameter
1957 /* If we're dealing with two pointer types or two enumeral types,
1958 we need candidates for both of them. */
1959 if (type2 && !same_type_p (type1, type2)
1960 && TREE_CODE (type1) == TREE_CODE (type2)
1961 && (TREE_CODE (type1) == REFERENCE_TYPE
1962 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1963 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1964 || TYPE_PTRMEMFUNC_P (type1)
1965 || IS_AGGR_TYPE (type1)
1966 || TREE_CODE (type1) == ENUMERAL_TYPE))
1968 build_builtin_candidate
1969 (candidates, fnname, type1, type1, args, argtypes, flags);
1970 build_builtin_candidate
1971 (candidates, fnname, type2, type2, args, argtypes, flags);
1975 build_builtin_candidate
1976 (candidates, fnname, type1, type2, args, argtypes, flags);
1980 type_decays_to (tree type)
1982 if (TREE_CODE (type) == ARRAY_TYPE)
1983 return build_pointer_type (TREE_TYPE (type));
1984 if (TREE_CODE (type) == FUNCTION_TYPE)
1985 return build_pointer_type (type);
1989 /* There are three conditions of builtin candidates:
1991 1) bool-taking candidates. These are the same regardless of the input.
1992 2) pointer-pair taking candidates. These are generated for each type
1993 one of the input types converts to.
1994 3) arithmetic candidates. According to the standard, we should generate
1995 all of these, but I'm trying not to...
1997 Here we generate a superset of the possible candidates for this particular
1998 case. That is a subset of the full set the standard defines, plus some
1999 other cases which the standard disallows. add_builtin_candidate will
2000 filter out the invalid set. */
2003 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2004 enum tree_code code2, tree fnname, tree *args,
2009 tree type, argtypes[3];
2010 /* TYPES[i] is the set of possible builtin-operator parameter types
2011 we will consider for the Ith argument. These are represented as
2012 a TREE_LIST; the TREE_VALUE of each node is the potential
2016 for (i = 0; i < 3; ++i)
2019 argtypes[i] = lvalue_type (args[i]);
2021 argtypes[i] = NULL_TREE;
2026 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2027 and VQ is either volatile or empty, there exist candidate operator
2028 functions of the form
2029 VQ T& operator++(VQ T&); */
2031 case POSTINCREMENT_EXPR:
2032 case PREINCREMENT_EXPR:
2033 case POSTDECREMENT_EXPR:
2034 case PREDECREMENT_EXPR:
2039 /* 24There also exist candidate operator functions of the form
2040 bool operator!(bool);
2041 bool operator&&(bool, bool);
2042 bool operator||(bool, bool); */
2044 case TRUTH_NOT_EXPR:
2045 build_builtin_candidate
2046 (candidates, fnname, boolean_type_node,
2047 NULL_TREE, args, argtypes, flags);
2050 case TRUTH_ORIF_EXPR:
2051 case TRUTH_ANDIF_EXPR:
2052 build_builtin_candidate
2053 (candidates, fnname, boolean_type_node,
2054 boolean_type_node, args, argtypes, flags);
2076 types[0] = types[1] = NULL_TREE;
2078 for (i = 0; i < 2; ++i)
2082 else if (IS_AGGR_TYPE (argtypes[i]))
2086 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2089 convs = lookup_conversions (argtypes[i]);
2091 if (code == COND_EXPR)
2093 if (real_lvalue_p (args[i]))
2094 types[i] = tree_cons
2095 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2097 types[i] = tree_cons
2098 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2104 for (; convs; convs = TREE_CHAIN (convs))
2106 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2109 && (TREE_CODE (type) != REFERENCE_TYPE
2110 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2113 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2114 types[i] = tree_cons (NULL_TREE, type, types[i]);
2116 type = non_reference (type);
2117 if (i != 0 || ! ref1)
2119 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2120 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2121 types[i] = tree_cons (NULL_TREE, type, types[i]);
2122 if (INTEGRAL_TYPE_P (type))
2123 type = type_promotes_to (type);
2126 if (! value_member (type, types[i]))
2127 types[i] = tree_cons (NULL_TREE, type, types[i]);
2132 if (code == COND_EXPR && real_lvalue_p (args[i]))
2133 types[i] = tree_cons
2134 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2135 type = non_reference (argtypes[i]);
2136 if (i != 0 || ! ref1)
2138 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2139 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2140 types[i] = tree_cons (NULL_TREE, type, types[i]);
2141 if (INTEGRAL_TYPE_P (type))
2142 type = type_promotes_to (type);
2144 types[i] = tree_cons (NULL_TREE, type, types[i]);
2148 /* Run through the possible parameter types of both arguments,
2149 creating candidates with those parameter types. */
2150 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2153 for (type = types[1]; type; type = TREE_CHAIN (type))
2154 add_builtin_candidate
2155 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2156 TREE_VALUE (type), args, argtypes, flags);
2158 add_builtin_candidate
2159 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2160 NULL_TREE, args, argtypes, flags);
2167 /* If TMPL can be successfully instantiated as indicated by
2168 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2170 TMPL is the template. EXPLICIT_TARGS are any explicit template
2171 arguments. ARGLIST is the arguments provided at the call-site.
2172 The RETURN_TYPE is the desired type for conversion operators. If
2173 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2174 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2175 add_conv_candidate. */
2177 static struct z_candidate*
2178 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2179 tree ctype, tree explicit_targs, tree arglist,
2180 tree return_type, tree access_path,
2181 tree conversion_path, int flags, tree obj,
2182 unification_kind_t strict)
2184 int ntparms = DECL_NTPARMS (tmpl);
2185 tree targs = make_tree_vec (ntparms);
2186 tree args_without_in_chrg = arglist;
2187 struct z_candidate *cand;
2191 /* We don't do deduction on the in-charge parameter, the VTT
2192 parameter or 'this'. */
2193 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2194 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2196 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2197 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2198 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2199 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2201 i = fn_type_unification (tmpl, explicit_targs, targs,
2202 args_without_in_chrg,
2203 return_type, strict, flags);
2208 fn = instantiate_template (tmpl, targs, tf_none);
2209 if (fn == error_mark_node)
2214 A member function template is never instantiated to perform the
2215 copy of a class object to an object of its class type.
2217 It's a little unclear what this means; the standard explicitly
2218 does allow a template to be used to copy a class. For example,
2223 template <class T> A(const T&);
2226 void g () { A a (f ()); }
2228 the member template will be used to make the copy. The section
2229 quoted above appears in the paragraph that forbids constructors
2230 whose only parameter is (a possibly cv-qualified variant of) the
2231 class type, and a logical interpretation is that the intent was
2232 to forbid the instantiation of member templates which would then
2234 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2236 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2237 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2242 if (obj != NULL_TREE)
2243 /* Aha, this is a conversion function. */
2244 cand = add_conv_candidate (candidates, fn, obj, access_path,
2245 conversion_path, arglist);
2247 cand = add_function_candidate (candidates, fn, ctype,
2248 arglist, access_path,
2249 conversion_path, flags);
2250 if (DECL_TI_TEMPLATE (fn) != tmpl)
2251 /* This situation can occur if a member template of a template
2252 class is specialized. Then, instantiate_template might return
2253 an instantiation of the specialization, in which case the
2254 DECL_TI_TEMPLATE field will point at the original
2255 specialization. For example:
2257 template <class T> struct S { template <class U> void f(U);
2258 template <> void f(int) {}; };
2262 Here, TMPL will be template <class U> S<double>::f(U).
2263 And, instantiate template will give us the specialization
2264 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2265 for this will point at template <class T> template <> S<T>::f(int),
2266 so that we can find the definition. For the purposes of
2267 overload resolution, however, we want the original TMPL. */
2268 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2270 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2276 static struct z_candidate *
2277 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2278 tree explicit_targs, tree arglist, tree return_type,
2279 tree access_path, tree conversion_path, int flags,
2280 unification_kind_t strict)
2283 add_template_candidate_real (candidates, tmpl, ctype,
2284 explicit_targs, arglist, return_type,
2285 access_path, conversion_path,
2286 flags, NULL_TREE, strict);
2290 static struct z_candidate *
2291 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2292 tree obj, tree arglist, tree return_type,
2293 tree access_path, tree conversion_path)
2296 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2297 arglist, return_type, access_path,
2298 conversion_path, 0, obj, DEDUCE_CONV);
2301 /* The CANDS are the set of candidates that were considered for
2302 overload resolution. Return the set of viable candidates. If none
2303 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2304 is true if a candidate should be considered viable only if it is
2307 static struct z_candidate*
2308 splice_viable (struct z_candidate *cands,
2312 struct z_candidate *viable;
2313 struct z_candidate **last_viable;
2314 struct z_candidate **cand;
2317 last_viable = &viable;
2318 *any_viable_p = false;
2323 struct z_candidate *c = *cand;
2324 if (strict_p ? c->viable == 1 : c->viable)
2329 last_viable = &c->next;
2330 *any_viable_p = true;
2336 return viable ? viable : cands;
2340 any_strictly_viable (struct z_candidate *cands)
2342 for (; cands; cands = cands->next)
2343 if (cands->viable == 1)
2348 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2349 words, it is about to become the "this" pointer for a member
2350 function call. Take the address of the object. */
2353 build_this (tree obj)
2355 /* In a template, we are only concerned about the type of the
2356 expression, so we can take a shortcut. */
2357 if (processing_template_decl)
2358 return build_address (obj);
2360 return build_unary_op (ADDR_EXPR, obj, 0);
2363 /* Returns true iff functions are equivalent. Equivalent functions are
2364 not '==' only if one is a function-local extern function or if
2365 both are extern "C". */
2368 equal_functions (tree fn1, tree fn2)
2370 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2371 || DECL_EXTERN_C_FUNCTION_P (fn1))
2372 return decls_match (fn1, fn2);
2376 /* Print information about one overload candidate CANDIDATE. MSGSTR
2377 is the text to print before the candidate itself.
2379 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2380 to have been run through gettext by the caller. This wart makes
2381 life simpler in print_z_candidates and for the translators. */
2384 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2386 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2388 if (candidate->num_convs == 3)
2389 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2390 candidate->convs[0]->type,
2391 candidate->convs[1]->type,
2392 candidate->convs[2]->type);
2393 else if (candidate->num_convs == 2)
2394 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2395 candidate->convs[0]->type,
2396 candidate->convs[1]->type);
2398 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2399 candidate->convs[0]->type);
2401 else if (TYPE_P (candidate->fn))
2402 inform ("%s %T <conversion>", msgstr, candidate->fn);
2403 else if (candidate->viable == -1)
2404 inform ("%s %+#D <near match>", msgstr, candidate->fn);
2406 inform ("%s %+#D", msgstr, candidate->fn);
2410 print_z_candidates (struct z_candidate *candidates)
2413 struct z_candidate *cand1;
2414 struct z_candidate **cand2;
2416 /* There may be duplicates in the set of candidates. We put off
2417 checking this condition as long as possible, since we have no way
2418 to eliminate duplicates from a set of functions in less than n^2
2419 time. Now we are about to emit an error message, so it is more
2420 permissible to go slowly. */
2421 for (cand1 = candidates; cand1; cand1 = cand1->next)
2423 tree fn = cand1->fn;
2424 /* Skip builtin candidates and conversion functions. */
2425 if (TREE_CODE (fn) != FUNCTION_DECL)
2427 cand2 = &cand1->next;
2430 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2431 && equal_functions (fn, (*cand2)->fn))
2432 *cand2 = (*cand2)->next;
2434 cand2 = &(*cand2)->next;
2441 str = _("candidates are:");
2442 print_z_candidate (str, candidates);
2443 if (candidates->next)
2445 /* Indent successive candidates by the width of the translation
2446 of the above string. */
2447 size_t len = gcc_gettext_width (str) + 1;
2448 char *spaces = alloca (len);
2449 memset (spaces, ' ', len-1);
2450 spaces[len - 1] = '\0';
2452 candidates = candidates->next;
2455 print_z_candidate (spaces, candidates);
2456 candidates = candidates->next;
2462 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2463 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2464 the result of the conversion function to convert it to the final
2465 desired type. Merge the two sequences into a single sequence,
2466 and return the merged sequence. */
2469 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2473 gcc_assert (user_seq->kind == ck_user);
2475 /* Find the end of the second conversion sequence. */
2477 while ((*t)->kind != ck_identity)
2478 t = &((*t)->u.next);
2480 /* Replace the identity conversion with the user conversion
2484 /* The entire sequence is a user-conversion sequence. */
2485 std_seq->user_conv_p = true;
2490 /* Returns the best overload candidate to perform the requested
2491 conversion. This function is used for three the overloading situations
2492 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2493 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2494 per [dcl.init.ref], so we ignore temporary bindings. */
2496 static struct z_candidate *
2497 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2499 struct z_candidate *candidates, *cand;
2500 tree fromtype = TREE_TYPE (expr);
2501 tree ctors = NULL_TREE;
2502 tree conv_fns = NULL_TREE;
2503 conversion *conv = NULL;
2504 tree args = NULL_TREE;
2507 /* We represent conversion within a hierarchy using RVALUE_CONV and
2508 BASE_CONV, as specified by [over.best.ics]; these become plain
2509 constructor calls, as specified in [dcl.init]. */
2510 gcc_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2511 || !DERIVED_FROM_P (totype, fromtype));
2513 if (IS_AGGR_TYPE (totype))
2514 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2516 if (IS_AGGR_TYPE (fromtype))
2517 conv_fns = lookup_conversions (fromtype);
2520 flags |= LOOKUP_NO_CONVERSION;
2526 ctors = BASELINK_FUNCTIONS (ctors);
2528 t = build_int_cst (build_pointer_type (totype), 0);
2529 args = build_tree_list (NULL_TREE, expr);
2530 /* We should never try to call the abstract or base constructor
2532 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2533 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2534 args = tree_cons (NULL_TREE, t, args);
2536 for (; ctors; ctors = OVL_NEXT (ctors))
2538 tree ctor = OVL_CURRENT (ctors);
2539 if (DECL_NONCONVERTING_P (ctor))
2542 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2543 cand = add_template_candidate (&candidates, ctor, totype,
2544 NULL_TREE, args, NULL_TREE,
2545 TYPE_BINFO (totype),
2546 TYPE_BINFO (totype),
2550 cand = add_function_candidate (&candidates, ctor, totype,
2551 args, TYPE_BINFO (totype),
2552 TYPE_BINFO (totype),
2556 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2560 args = build_tree_list (NULL_TREE, build_this (expr));
2562 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2565 tree conversion_path = TREE_PURPOSE (conv_fns);
2566 int convflags = LOOKUP_NO_CONVERSION;
2568 /* If we are called to convert to a reference type, we are trying to
2569 find an lvalue binding, so don't even consider temporaries. If
2570 we don't find an lvalue binding, the caller will try again to
2571 look for a temporary binding. */
2572 if (TREE_CODE (totype) == REFERENCE_TYPE)
2573 convflags |= LOOKUP_NO_TEMP_BIND;
2575 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2577 tree fn = OVL_CURRENT (fns);
2579 /* [over.match.funcs] For conversion functions, the function
2580 is considered to be a member of the class of the implicit
2581 object argument for the purpose of defining the type of
2582 the implicit object parameter.
2584 So we pass fromtype as CTYPE to add_*_candidate. */
2586 if (TREE_CODE (fn) == TEMPLATE_DECL)
2587 cand = add_template_candidate (&candidates, fn, fromtype,
2590 TYPE_BINFO (fromtype),
2595 cand = add_function_candidate (&candidates, fn, fromtype,
2597 TYPE_BINFO (fromtype),
2604 = implicit_conversion (totype,
2605 TREE_TYPE (TREE_TYPE (cand->fn)),
2607 /*c_cast_p=*/false, convflags);
2609 cand->second_conv = ics;
2613 else if (candidates->viable == 1 && ics->bad_p)
2619 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2623 cand = tourney (candidates);
2626 if (flags & LOOKUP_COMPLAIN)
2628 error ("conversion from %qT to %qT is ambiguous",
2630 print_z_candidates (candidates);
2633 cand = candidates; /* any one will do */
2634 cand->second_conv = build_ambiguous_conv (totype, expr);
2635 cand->second_conv->user_conv_p = true;
2636 if (!any_strictly_viable (candidates))
2637 cand->second_conv->bad_p = true;
2638 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2639 ambiguous conversion is no worse than another user-defined
2645 /* Build the user conversion sequence. */
2648 (DECL_CONSTRUCTOR_P (cand->fn)
2649 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2650 build_identity_conv (TREE_TYPE (expr), expr));
2653 /* Combine it with the second conversion sequence. */
2654 cand->second_conv = merge_conversion_sequences (conv,
2657 if (cand->viable == -1)
2658 cand->second_conv->bad_p = true;
2664 build_user_type_conversion (tree totype, tree expr, int flags)
2666 struct z_candidate *cand
2667 = build_user_type_conversion_1 (totype, expr, flags);
2671 if (cand->second_conv->kind == ck_ambig)
2672 return error_mark_node;
2673 expr = convert_like (cand->second_conv, expr);
2674 return convert_from_reference (expr);
2679 /* Do any initial processing on the arguments to a function call. */
2682 resolve_args (tree args)
2685 for (t = args; t; t = TREE_CHAIN (t))
2687 tree arg = TREE_VALUE (t);
2689 if (error_operand_p (arg))
2690 return error_mark_node;
2691 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2693 error ("invalid use of void expression");
2694 return error_mark_node;
2700 /* Perform overload resolution on FN, which is called with the ARGS.
2702 Return the candidate function selected by overload resolution, or
2703 NULL if the event that overload resolution failed. In the case
2704 that overload resolution fails, *CANDIDATES will be the set of
2705 candidates considered, and ANY_VIABLE_P will be set to true or
2706 false to indicate whether or not any of the candidates were
2709 The ARGS should already have gone through RESOLVE_ARGS before this
2710 function is called. */
2712 static struct z_candidate *
2713 perform_overload_resolution (tree fn,
2715 struct z_candidate **candidates,
2718 struct z_candidate *cand;
2719 tree explicit_targs = NULL_TREE;
2720 int template_only = 0;
2723 *any_viable_p = true;
2725 /* Check FN and ARGS. */
2726 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2727 || TREE_CODE (fn) == TEMPLATE_DECL
2728 || TREE_CODE (fn) == OVERLOAD
2729 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2730 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2732 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2734 explicit_targs = TREE_OPERAND (fn, 1);
2735 fn = TREE_OPERAND (fn, 0);
2739 /* Add the various candidate functions. */
2740 add_candidates (fn, args, explicit_targs, template_only,
2741 /*conversion_path=*/NULL_TREE,
2742 /*access_path=*/NULL_TREE,
2746 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2750 cand = tourney (*candidates);
2754 /* Return an expression for a call to FN (a namespace-scope function,
2755 or a static member function) with the ARGS. */
2758 build_new_function_call (tree fn, tree args, bool koenig_p)
2760 struct z_candidate *candidates, *cand;
2765 args = resolve_args (args);
2766 if (args == error_mark_node)
2767 return error_mark_node;
2769 /* If this function was found without using argument dependent
2770 lookup, then we want to ignore any undeclared friend
2776 fn = remove_hidden_names (fn);
2779 error ("no matching function for call to %<%D(%A)%>",
2780 DECL_NAME (OVL_CURRENT (orig_fn)), args);
2781 return error_mark_node;
2785 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2786 p = conversion_obstack_alloc (0);
2788 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2792 if (!any_viable_p && candidates && ! candidates->next)
2793 return build_function_call (candidates->fn, args);
2794 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2795 fn = TREE_OPERAND (fn, 0);
2797 error ("no matching function for call to %<%D(%A)%>",
2798 DECL_NAME (OVL_CURRENT (fn)), args);
2800 error ("call of overloaded %<%D(%A)%> is ambiguous",
2801 DECL_NAME (OVL_CURRENT (fn)), args);
2803 print_z_candidates (candidates);
2804 result = error_mark_node;
2807 result = build_over_call (cand, LOOKUP_NORMAL);
2809 /* Free all the conversions we allocated. */
2810 obstack_free (&conversion_obstack, p);
2815 /* Build a call to a global operator new. FNNAME is the name of the
2816 operator (either "operator new" or "operator new[]") and ARGS are
2817 the arguments provided. *SIZE points to the total number of bytes
2818 required by the allocation, and is updated if that is changed here.
2819 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2820 function determines that no cookie should be used, after all,
2821 *COOKIE_SIZE is set to NULL_TREE. */
2824 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2827 struct z_candidate *candidates;
2828 struct z_candidate *cand;
2831 args = tree_cons (NULL_TREE, *size, args);
2832 args = resolve_args (args);
2833 if (args == error_mark_node)
2840 If this lookup fails to find the name, or if the allocated type
2841 is not a class type, the allocation function's name is looked
2842 up in the global scope.
2844 we disregard block-scope declarations of "operator new". */
2845 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2847 /* Figure out what function is being called. */
2848 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2850 /* If no suitable function could be found, issue an error message
2855 error ("no matching function for call to %<%D(%A)%>",
2856 DECL_NAME (OVL_CURRENT (fns)), args);
2858 error ("call of overloaded %<%D(%A)%> is ambiguous",
2859 DECL_NAME (OVL_CURRENT (fns)), args);
2861 print_z_candidates (candidates);
2862 return error_mark_node;
2865 /* If a cookie is required, add some extra space. Whether
2866 or not a cookie is required cannot be determined until
2867 after we know which function was called. */
2870 bool use_cookie = true;
2871 if (!abi_version_at_least (2))
2873 tree placement = TREE_CHAIN (args);
2874 /* In G++ 3.2, the check was implemented incorrectly; it
2875 looked at the placement expression, rather than the
2876 type of the function. */
2877 if (placement && !TREE_CHAIN (placement)
2878 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2886 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2887 /* Skip the size_t parameter. */
2888 arg_types = TREE_CHAIN (arg_types);
2889 /* Check the remaining parameters (if any). */
2891 && TREE_CHAIN (arg_types) == void_list_node
2892 && same_type_p (TREE_VALUE (arg_types),
2896 /* If we need a cookie, adjust the number of bytes allocated. */
2899 /* Update the total size. */
2900 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2901 /* Update the argument list to reflect the adjusted size. */
2902 TREE_VALUE (args) = *size;
2905 *cookie_size = NULL_TREE;
2908 /* Build the CALL_EXPR. */
2909 return build_over_call (cand, LOOKUP_NORMAL);
2913 build_object_call (tree obj, tree args)
2915 struct z_candidate *candidates = 0, *cand;
2916 tree fns, convs, mem_args = NULL_TREE;
2917 tree type = TREE_TYPE (obj);
2919 tree result = NULL_TREE;
2922 if (TYPE_PTRMEMFUNC_P (type))
2924 /* It's no good looking for an overloaded operator() on a
2925 pointer-to-member-function. */
2926 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2927 return error_mark_node;
2930 if (TYPE_BINFO (type))
2932 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2933 if (fns == error_mark_node)
2934 return error_mark_node;
2939 args = resolve_args (args);
2941 if (args == error_mark_node)
2942 return error_mark_node;
2944 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2945 p = conversion_obstack_alloc (0);
2949 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2950 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2952 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2954 tree fn = OVL_CURRENT (fns);
2955 if (TREE_CODE (fn) == TEMPLATE_DECL)
2956 add_template_candidate (&candidates, fn, base, NULL_TREE,
2957 mem_args, NULL_TREE,
2960 LOOKUP_NORMAL, DEDUCE_CALL);
2962 add_function_candidate
2963 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2964 TYPE_BINFO (type), LOOKUP_NORMAL);
2968 convs = lookup_conversions (type);
2970 for (; convs; convs = TREE_CHAIN (convs))
2972 tree fns = TREE_VALUE (convs);
2973 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2975 if ((TREE_CODE (totype) == POINTER_TYPE
2976 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2977 || (TREE_CODE (totype) == REFERENCE_TYPE
2978 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2979 || (TREE_CODE (totype) == REFERENCE_TYPE
2980 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2981 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2982 for (; fns; fns = OVL_NEXT (fns))
2984 tree fn = OVL_CURRENT (fns);
2985 if (TREE_CODE (fn) == TEMPLATE_DECL)
2986 add_template_conv_candidate
2987 (&candidates, fn, obj, args, totype,
2988 /*access_path=*/NULL_TREE,
2989 /*conversion_path=*/NULL_TREE);
2991 add_conv_candidate (&candidates, fn, obj, args,
2992 /*conversion_path=*/NULL_TREE,
2993 /*access_path=*/NULL_TREE);
2997 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3000 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3001 print_z_candidates (candidates);
3002 result = error_mark_node;
3006 cand = tourney (candidates);
3009 error ("call of %<(%T) (%A)%> is ambiguous", TREE_TYPE (obj), args);
3010 print_z_candidates (candidates);
3011 result = error_mark_node;
3013 /* Since cand->fn will be a type, not a function, for a conversion
3014 function, we must be careful not to unconditionally look at
3016 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3017 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3018 result = build_over_call (cand, LOOKUP_NORMAL);
3021 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
3022 obj = convert_from_reference (obj);
3023 result = build_function_call (obj, args);
3027 /* Free all the conversions we allocated. */
3028 obstack_free (&conversion_obstack, p);
3034 op_error (enum tree_code code, enum tree_code code2,
3035 tree arg1, tree arg2, tree arg3, const char *problem)
3039 if (code == MODIFY_EXPR)
3040 opname = assignment_operator_name_info[code2].name;
3042 opname = operator_name_info[code].name;
3047 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3048 problem, arg1, arg2, arg3);
3051 case POSTINCREMENT_EXPR:
3052 case POSTDECREMENT_EXPR:
3053 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3057 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3062 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3067 error ("%s for %<operator%s%> in %<%E %s %E%>",
3068 problem, opname, arg1, opname, arg2);
3070 error ("%s for %<operator%s%> in %<%s%E%>",
3071 problem, opname, opname, arg1);
3076 /* Return the implicit conversion sequence that could be used to
3077 convert E1 to E2 in [expr.cond]. */
3080 conditional_conversion (tree e1, tree e2)
3082 tree t1 = non_reference (TREE_TYPE (e1));
3083 tree t2 = non_reference (TREE_TYPE (e2));
3089 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3090 implicitly converted (clause _conv_) to the type "reference to
3091 T2", subject to the constraint that in the conversion the
3092 reference must bind directly (_dcl.init.ref_) to E1. */
3093 if (real_lvalue_p (e2))
3095 conv = implicit_conversion (build_reference_type (t2),
3099 LOOKUP_NO_TEMP_BIND);
3106 If E1 and E2 have class type, and the underlying class types are
3107 the same or one is a base class of the other: E1 can be converted
3108 to match E2 if the class of T2 is the same type as, or a base
3109 class of, the class of T1, and the cv-qualification of T2 is the
3110 same cv-qualification as, or a greater cv-qualification than, the
3111 cv-qualification of T1. If the conversion is applied, E1 is
3112 changed to an rvalue of type T2 that still refers to the original
3113 source class object (or the appropriate subobject thereof). */
3114 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3115 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3117 if (good_base && at_least_as_qualified_p (t2, t1))
3119 conv = build_identity_conv (t1, e1);
3120 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3121 TYPE_MAIN_VARIANT (t2)))
3122 conv = build_conv (ck_base, t2, conv);
3124 conv = build_conv (ck_rvalue, t2, conv);
3133 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3134 converted to the type that expression E2 would have if E2 were
3135 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3136 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3140 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3141 arguments to the conditional expression. */
3144 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3148 tree result = NULL_TREE;
3149 tree result_type = NULL_TREE;
3150 bool lvalue_p = true;
3151 struct z_candidate *candidates = 0;
3152 struct z_candidate *cand;
3155 /* As a G++ extension, the second argument to the conditional can be
3156 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3157 c'.) If the second operand is omitted, make sure it is
3158 calculated only once. */
3162 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3164 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3165 if (real_lvalue_p (arg1))
3166 arg2 = arg1 = stabilize_reference (arg1);
3168 arg2 = arg1 = save_expr (arg1);
3173 The first expr ession is implicitly converted to bool (clause
3175 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3177 /* If something has already gone wrong, just pass that fact up the
3179 if (error_operand_p (arg1)
3180 || error_operand_p (arg2)
3181 || error_operand_p (arg3))
3182 return error_mark_node;
3186 If either the second or the third operand has type (possibly
3187 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3188 array-to-pointer (_conv.array_), and function-to-pointer
3189 (_conv.func_) standard conversions are performed on the second
3190 and third operands. */
3191 arg2_type = TREE_TYPE (arg2);
3192 arg3_type = TREE_TYPE (arg3);
3193 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3195 /* Do the conversions. We don't these for `void' type arguments
3196 since it can't have any effect and since decay_conversion
3197 does not handle that case gracefully. */
3198 if (!VOID_TYPE_P (arg2_type))
3199 arg2 = decay_conversion (arg2);
3200 if (!VOID_TYPE_P (arg3_type))
3201 arg3 = decay_conversion (arg3);
3202 arg2_type = TREE_TYPE (arg2);
3203 arg3_type = TREE_TYPE (arg3);
3207 One of the following shall hold:
3209 --The second or the third operand (but not both) is a
3210 throw-expression (_except.throw_); the result is of the
3211 type of the other and is an rvalue.
3213 --Both the second and the third operands have type void; the
3214 result is of type void and is an rvalue.
3216 We must avoid calling force_rvalue for expressions of type
3217 "void" because it will complain that their value is being
3219 if (TREE_CODE (arg2) == THROW_EXPR
3220 && TREE_CODE (arg3) != THROW_EXPR)
3222 if (!VOID_TYPE_P (arg3_type))
3223 arg3 = force_rvalue (arg3);
3224 arg3_type = TREE_TYPE (arg3);
3225 result_type = arg3_type;
3227 else if (TREE_CODE (arg2) != THROW_EXPR
3228 && TREE_CODE (arg3) == THROW_EXPR)
3230 if (!VOID_TYPE_P (arg2_type))
3231 arg2 = force_rvalue (arg2);
3232 arg2_type = TREE_TYPE (arg2);
3233 result_type = arg2_type;
3235 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3236 result_type = void_type_node;
3239 error ("%qE has type %<void%> and is not a throw-expression",
3240 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3241 return error_mark_node;
3245 goto valid_operands;
3249 Otherwise, if the second and third operand have different types,
3250 and either has (possibly cv-qualified) class type, an attempt is
3251 made to convert each of those operands to the type of the other. */
3252 else if (!same_type_p (arg2_type, arg3_type)
3253 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3258 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3259 p = conversion_obstack_alloc (0);
3261 conv2 = conditional_conversion (arg2, arg3);
3262 conv3 = conditional_conversion (arg3, arg2);
3266 If both can be converted, or one can be converted but the
3267 conversion is ambiguous, the program is ill-formed. If
3268 neither can be converted, the operands are left unchanged and
3269 further checking is performed as described below. If exactly
3270 one conversion is possible, that conversion is applied to the
3271 chosen operand and the converted operand is used in place of
3272 the original operand for the remainder of this section. */
3273 if ((conv2 && !conv2->bad_p
3274 && conv3 && !conv3->bad_p)
3275 || (conv2 && conv2->kind == ck_ambig)
3276 || (conv3 && conv3->kind == ck_ambig))
3278 error ("operands to ?: have different types");
3279 result = error_mark_node;
3281 else if (conv2 && (!conv2->bad_p || !conv3))
3283 arg2 = convert_like (conv2, arg2);
3284 arg2 = convert_from_reference (arg2);
3285 arg2_type = TREE_TYPE (arg2);
3287 else if (conv3 && (!conv3->bad_p || !conv2))
3289 arg3 = convert_like (conv3, arg3);
3290 arg3 = convert_from_reference (arg3);
3291 arg3_type = TREE_TYPE (arg3);
3294 /* Free all the conversions we allocated. */
3295 obstack_free (&conversion_obstack, p);
3300 /* If, after the conversion, both operands have class type,
3301 treat the cv-qualification of both operands as if it were the
3302 union of the cv-qualification of the operands.
3304 The standard is not clear about what to do in this
3305 circumstance. For example, if the first operand has type
3306 "const X" and the second operand has a user-defined
3307 conversion to "volatile X", what is the type of the second
3308 operand after this step? Making it be "const X" (matching
3309 the first operand) seems wrong, as that discards the
3310 qualification without actually performing a copy. Leaving it
3311 as "volatile X" seems wrong as that will result in the
3312 conditional expression failing altogether, even though,
3313 according to this step, the one operand could be converted to
3314 the type of the other. */
3315 if ((conv2 || conv3)
3316 && CLASS_TYPE_P (arg2_type)
3317 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3318 arg2_type = arg3_type =
3319 cp_build_qualified_type (arg2_type,
3320 TYPE_QUALS (arg2_type)
3321 | TYPE_QUALS (arg3_type));
3326 If the second and third operands are lvalues and have the same
3327 type, the result is of that type and is an lvalue. */
3328 if (real_lvalue_p (arg2)
3329 && real_lvalue_p (arg3)
3330 && same_type_p (arg2_type, arg3_type))
3332 result_type = arg2_type;
3333 goto valid_operands;
3338 Otherwise, the result is an rvalue. If the second and third
3339 operand do not have the same type, and either has (possibly
3340 cv-qualified) class type, overload resolution is used to
3341 determine the conversions (if any) to be applied to the operands
3342 (_over.match.oper_, _over.built_). */
3344 if (!same_type_p (arg2_type, arg3_type)
3345 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3351 /* Rearrange the arguments so that add_builtin_candidate only has
3352 to know about two args. In build_builtin_candidates, the
3353 arguments are unscrambled. */
3357 add_builtin_candidates (&candidates,
3360 ansi_opname (COND_EXPR),
3366 If the overload resolution fails, the program is
3368 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3371 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3372 print_z_candidates (candidates);
3373 return error_mark_node;
3375 cand = tourney (candidates);
3378 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3379 print_z_candidates (candidates);
3380 return error_mark_node;
3385 Otherwise, the conversions thus determined are applied, and
3386 the converted operands are used in place of the original
3387 operands for the remainder of this section. */
3388 conv = cand->convs[0];
3389 arg1 = convert_like (conv, arg1);
3390 conv = cand->convs[1];
3391 arg2 = convert_like (conv, arg2);
3392 conv = cand->convs[2];
3393 arg3 = convert_like (conv, arg3);
3398 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3399 and function-to-pointer (_conv.func_) standard conversions are
3400 performed on the second and third operands.
3402 We need to force the lvalue-to-rvalue conversion here for class types,
3403 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3404 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3407 arg2 = force_rvalue (arg2);
3408 if (!CLASS_TYPE_P (arg2_type))
3409 arg2_type = TREE_TYPE (arg2);
3411 arg3 = force_rvalue (arg3);
3412 if (!CLASS_TYPE_P (arg2_type))
3413 arg3_type = TREE_TYPE (arg3);
3415 if (arg2 == error_mark_node || arg3 == error_mark_node)
3416 return error_mark_node;
3420 After those conversions, one of the following shall hold:
3422 --The second and third operands have the same type; the result is of
3424 if (same_type_p (arg2_type, arg3_type))
3425 result_type = arg2_type;
3428 --The second and third operands have arithmetic or enumeration
3429 type; the usual arithmetic conversions are performed to bring
3430 them to a common type, and the result is of that type. */
3431 else if ((ARITHMETIC_TYPE_P (arg2_type)
3432 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3433 && (ARITHMETIC_TYPE_P (arg3_type)
3434 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3436 /* In this case, there is always a common type. */
3437 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3440 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3441 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3442 warning (0, "enumeral mismatch in conditional expression: %qT vs %qT",
3443 arg2_type, arg3_type);
3444 else if (extra_warnings
3445 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3446 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3447 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3448 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3449 warning (0, "enumeral and non-enumeral type in conditional expression");
3451 arg2 = perform_implicit_conversion (result_type, arg2);
3452 arg3 = perform_implicit_conversion (result_type, arg3);
3456 --The second and third operands have pointer type, or one has
3457 pointer type and the other is a null pointer constant; pointer
3458 conversions (_conv.ptr_) and qualification conversions
3459 (_conv.qual_) are performed to bring them to their composite
3460 pointer type (_expr.rel_). The result is of the composite
3463 --The second and third operands have pointer to member type, or
3464 one has pointer to member type and the other is a null pointer
3465 constant; pointer to member conversions (_conv.mem_) and
3466 qualification conversions (_conv.qual_) are performed to bring
3467 them to a common type, whose cv-qualification shall match the
3468 cv-qualification of either the second or the third operand.
3469 The result is of the common type. */
3470 else if ((null_ptr_cst_p (arg2)
3471 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3472 || (null_ptr_cst_p (arg3)
3473 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3474 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3475 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3476 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3478 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3479 arg3, "conditional expression");
3480 if (result_type == error_mark_node)
3481 return error_mark_node;
3482 arg2 = perform_implicit_conversion (result_type, arg2);
3483 arg3 = perform_implicit_conversion (result_type, arg3);
3488 error ("operands to ?: have different types");
3489 return error_mark_node;
3493 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3495 /* We can't use result_type below, as fold might have returned a
3498 /* Expand both sides into the same slot, hopefully the target of the
3499 ?: expression. We used to check for TARGET_EXPRs here, but now we
3500 sometimes wrap them in NOP_EXPRs so the test would fail. */
3501 if (!lvalue_p && CLASS_TYPE_P (TREE_TYPE (result)))
3502 result = get_target_expr (result);
3504 /* If this expression is an rvalue, but might be mistaken for an
3505 lvalue, we must add a NON_LVALUE_EXPR. */
3506 if (!lvalue_p && real_lvalue_p (result))
3507 result = rvalue (result);
3512 /* OPERAND is an operand to an expression. Perform necessary steps
3513 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3517 prep_operand (tree operand)
3521 if (CLASS_TYPE_P (TREE_TYPE (operand))
3522 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3523 /* Make sure the template type is instantiated now. */
3524 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3530 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3531 OVERLOAD) to the CANDIDATES, returning an updated list of
3532 CANDIDATES. The ARGS are the arguments provided to the call,
3533 without any implicit object parameter. The EXPLICIT_TARGS are
3534 explicit template arguments provided. TEMPLATE_ONLY is true if
3535 only template functions should be considered. CONVERSION_PATH,
3536 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3539 add_candidates (tree fns, tree args,
3540 tree explicit_targs, bool template_only,
3541 tree conversion_path, tree access_path,
3543 struct z_candidate **candidates)
3546 tree non_static_args;
3548 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3549 /* Delay creating the implicit this parameter until it is needed. */
3550 non_static_args = NULL_TREE;
3557 fn = OVL_CURRENT (fns);
3558 /* Figure out which set of arguments to use. */
3559 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3561 /* If this function is a non-static member, prepend the implicit
3562 object parameter. */
3563 if (!non_static_args)
3564 non_static_args = tree_cons (NULL_TREE,
3565 build_this (TREE_VALUE (args)),
3567 fn_args = non_static_args;
3570 /* Otherwise, just use the list of arguments provided. */
3573 if (TREE_CODE (fn) == TEMPLATE_DECL)
3574 add_template_candidate (candidates,
3584 else if (!template_only)
3585 add_function_candidate (candidates,
3592 fns = OVL_NEXT (fns);
3597 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3600 struct z_candidate *candidates = 0, *cand;
3601 tree arglist, fnname;
3603 tree result = NULL_TREE;
3604 bool result_valid_p = false;
3605 enum tree_code code2 = NOP_EXPR;
3611 if (error_operand_p (arg1)
3612 || error_operand_p (arg2)
3613 || error_operand_p (arg3))
3614 return error_mark_node;
3616 if (code == MODIFY_EXPR)
3618 code2 = TREE_CODE (arg3);
3620 fnname = ansi_assopname (code2);
3623 fnname = ansi_opname (code);
3625 arg1 = prep_operand (arg1);
3631 case VEC_DELETE_EXPR:
3633 /* Use build_op_new_call and build_op_delete_call instead. */
3637 return build_object_call (arg1, arg2);
3643 arg2 = prep_operand (arg2);
3644 arg3 = prep_operand (arg3);
3646 if (code == COND_EXPR)
3648 if (arg2 == NULL_TREE
3649 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3650 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3651 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3652 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3655 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3656 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3659 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3660 arg2 = integer_zero_node;
3662 arglist = NULL_TREE;
3664 arglist = tree_cons (NULL_TREE, arg3, arglist);
3666 arglist = tree_cons (NULL_TREE, arg2, arglist);
3667 arglist = tree_cons (NULL_TREE, arg1, arglist);
3669 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3670 p = conversion_obstack_alloc (0);
3672 /* Add namespace-scope operators to the list of functions to
3674 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3675 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3676 flags, &candidates);
3677 /* Add class-member operators to the candidate set. */
3678 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3682 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3683 if (fns == error_mark_node)
3685 result = error_mark_node;
3686 goto user_defined_result_ready;
3689 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3691 BASELINK_BINFO (fns),
3692 TYPE_BINFO (TREE_TYPE (arg1)),
3693 flags, &candidates);
3696 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3697 to know about two args; a builtin candidate will always have a first
3698 parameter of type bool. We'll handle that in
3699 build_builtin_candidate. */
3700 if (code == COND_EXPR)
3710 args[2] = NULL_TREE;
3713 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3719 /* For these, the built-in candidates set is empty
3720 [over.match.oper]/3. We don't want non-strict matches
3721 because exact matches are always possible with built-in
3722 operators. The built-in candidate set for COMPONENT_REF
3723 would be empty too, but since there are no such built-in
3724 operators, we accept non-strict matches for them. */
3729 strict_p = pedantic;
3733 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3738 case POSTINCREMENT_EXPR:
3739 case POSTDECREMENT_EXPR:
3740 /* Look for an `operator++ (int)'. If they didn't have
3741 one, then we fall back to the old way of doing things. */
3742 if (flags & LOOKUP_COMPLAIN)
3743 pedwarn ("no %<%D(int)%> declared for postfix %qs, "
3744 "trying prefix operator instead",
3746 operator_name_info[code].name);
3747 if (code == POSTINCREMENT_EXPR)
3748 code = PREINCREMENT_EXPR;
3750 code = PREDECREMENT_EXPR;
3751 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3755 /* The caller will deal with these. */
3760 result_valid_p = true;
3764 if (flags & LOOKUP_COMPLAIN)
3766 op_error (code, code2, arg1, arg2, arg3, "no match");
3767 print_z_candidates (candidates);
3769 result = error_mark_node;
3775 cand = tourney (candidates);
3778 if (flags & LOOKUP_COMPLAIN)
3780 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3781 print_z_candidates (candidates);
3783 result = error_mark_node;
3785 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3788 *overloaded_p = true;
3790 result = build_over_call (cand, LOOKUP_NORMAL);
3794 /* Give any warnings we noticed during overload resolution. */
3797 struct candidate_warning *w;
3798 for (w = cand->warnings; w; w = w->next)
3799 joust (cand, w->loser, 1);
3802 /* Check for comparison of different enum types. */
3811 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3812 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3813 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3814 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3816 warning (0, "comparison between %q#T and %q#T",
3817 TREE_TYPE (arg1), TREE_TYPE (arg2));
3824 /* We need to strip any leading REF_BIND so that bitfields
3825 don't cause errors. This should not remove any important
3826 conversions, because builtins don't apply to class
3827 objects directly. */
3828 conv = cand->convs[0];
3829 if (conv->kind == ck_ref_bind)
3830 conv = conv->u.next;
3831 arg1 = convert_like (conv, arg1);
3834 conv = cand->convs[1];
3835 if (conv->kind == ck_ref_bind)
3836 conv = conv->u.next;
3837 arg2 = convert_like (conv, arg2);
3841 conv = cand->convs[2];
3842 if (conv->kind == ck_ref_bind)
3843 conv = conv->u.next;
3844 arg3 = convert_like (conv, arg3);
3849 user_defined_result_ready:
3851 /* Free all the conversions we allocated. */
3852 obstack_free (&conversion_obstack, p);
3854 if (result || result_valid_p)
3861 return build_modify_expr (arg1, code2, arg2);
3864 return build_indirect_ref (arg1, "unary *");
3869 case TRUNC_DIV_EXPR:
3880 case TRUNC_MOD_EXPR:
3884 case TRUTH_ANDIF_EXPR:
3885 case TRUTH_ORIF_EXPR:
3886 return cp_build_binary_op (code, arg1, arg2);
3888 case UNARY_PLUS_EXPR:
3891 case TRUTH_NOT_EXPR:
3892 case PREINCREMENT_EXPR:
3893 case POSTINCREMENT_EXPR:
3894 case PREDECREMENT_EXPR:
3895 case POSTDECREMENT_EXPR:
3898 return build_unary_op (code, arg1, candidates != 0);
3901 return build_array_ref (arg1, arg2);
3904 return build_conditional_expr (arg1, arg2, arg3);
3907 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
3909 /* The caller will deal with these. */
3921 /* Build a call to operator delete. This has to be handled very specially,
3922 because the restrictions on what signatures match are different from all
3923 other call instances. For a normal delete, only a delete taking (void *)
3924 or (void *, size_t) is accepted. For a placement delete, only an exact
3925 match with the placement new is accepted.
3927 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3928 ADDR is the pointer to be deleted.
3929 SIZE is the size of the memory block to be deleted.
3930 GLOBAL_P is true if the delete-expression should not consider
3931 class-specific delete operators.
3932 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3935 build_op_delete_call (enum tree_code code, tree addr, tree size,
3936 bool global_p, tree placement)
3938 tree fn = NULL_TREE;
3939 tree fns, fnname, argtypes, args, type;
3942 if (addr == error_mark_node)
3943 return error_mark_node;
3945 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3947 fnname = ansi_opname (code);
3949 if (CLASS_TYPE_P (type)
3950 && COMPLETE_TYPE_P (complete_type (type))
3954 If the result of the lookup is ambiguous or inaccessible, or if
3955 the lookup selects a placement deallocation function, the
3956 program is ill-formed.
3958 Therefore, we ask lookup_fnfields to complain about ambiguity. */
3960 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3961 if (fns == error_mark_node)
3962 return error_mark_node;
3967 if (fns == NULL_TREE)
3968 fns = lookup_name_nonclass (fnname);
3975 /* Find the allocation function that is being called. */
3976 call_expr = placement;
3977 /* Extract the function. */
3978 alloc_fn = get_callee_fndecl (call_expr);
3979 gcc_assert (alloc_fn != NULL_TREE);
3980 /* Then the second parm type. */
3981 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3982 /* Also the second argument. */
3983 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3987 /* First try it without the size argument. */
3988 argtypes = void_list_node;
3992 /* Strip const and volatile from addr. */
3993 addr = cp_convert (ptr_type_node, addr);
3995 /* We make two tries at finding a matching `operator delete'. On
3996 the first pass, we look for a one-operator (or placement)
3997 operator delete. If we're not doing placement delete, then on
3998 the second pass we look for a two-argument delete. */
3999 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4001 /* Go through the `operator delete' functions looking for one
4002 with a matching type. */
4003 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4009 /* The first argument must be "void *". */
4010 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4011 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4014 /* On the first pass, check the rest of the arguments. */
4020 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4028 /* On the second pass, the second argument must be
4031 && same_type_p (TREE_VALUE (t), sizetype)
4032 && TREE_CHAIN (t) == void_list_node)
4036 /* If we found a match, we're done. */
4041 /* If we have a matching function, call it. */
4044 /* Make sure we have the actual function, and not an
4046 fn = OVL_CURRENT (fn);
4048 /* If the FN is a member function, make sure that it is
4050 if (DECL_CLASS_SCOPE_P (fn))
4051 perform_or_defer_access_check (TYPE_BINFO (type), fn);
4054 args = tree_cons (NULL_TREE, addr, args);
4056 args = tree_cons (NULL_TREE, addr,
4057 build_tree_list (NULL_TREE, size));
4061 /* The placement args might not be suitable for overload
4062 resolution at this point, so build the call directly. */
4064 return build_cxx_call (fn, args);
4067 return build_function_call (fn, args);
4070 /* If we are doing placement delete we do nothing if we don't find a
4071 matching op delete. */
4075 error ("no suitable %<operator %s%> for %qT",
4076 operator_name_info[(int)code].name, type);
4077 return error_mark_node;
4080 /* If the current scope isn't allowed to access DECL along
4081 BASETYPE_PATH, give an error. The most derived class in
4082 BASETYPE_PATH is the one used to qualify DECL. */
4085 enforce_access (tree basetype_path, tree decl)
4087 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4089 if (!accessible_p (basetype_path, decl, true))
4091 if (TREE_PRIVATE (decl))
4092 error ("%q+#D is private", decl);
4093 else if (TREE_PROTECTED (decl))
4094 error ("%q+#D is protected", decl);
4096 error ("%q+#D is inaccessible", decl);
4097 error ("within this context");
4104 /* Check that a callable constructor to initialize a temporary of
4105 TYPE from an EXPR exists. */
4108 check_constructor_callable (tree type, tree expr)
4110 build_special_member_call (NULL_TREE,
4111 complete_ctor_identifier,
4112 build_tree_list (NULL_TREE, expr),
4114 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4115 | LOOKUP_NO_CONVERSION
4116 | LOOKUP_CONSTRUCTOR_CALLABLE);
4119 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4120 bitwise or of LOOKUP_* values. If any errors are warnings are
4121 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4122 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4126 build_temp (tree expr, tree type, int flags,
4127 diagnostic_fn_t *diagnostic_fn)
4131 savew = warningcount, savee = errorcount;
4132 expr = build_special_member_call (NULL_TREE,
4133 complete_ctor_identifier,
4134 build_tree_list (NULL_TREE, expr),
4136 if (warningcount > savew)
4137 *diagnostic_fn = warning0;
4138 else if (errorcount > savee)
4139 *diagnostic_fn = error;
4141 *diagnostic_fn = NULL;
4146 /* Perform the conversions in CONVS on the expression EXPR. FN and
4147 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4148 indicates the `this' argument of a method. INNER is nonzero when
4149 being called to continue a conversion chain. It is negative when a
4150 reference binding will be applied, positive otherwise. If
4151 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4152 conversions will be emitted if appropriate. If C_CAST_P is true,
4153 this conversion is coming from a C-style cast; in that case,
4154 conversions to inaccessible bases are permitted. */
4157 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4158 int inner, bool issue_conversion_warnings,
4161 tree totype = convs->type;
4162 diagnostic_fn_t diagnostic_fn;
4165 && convs->kind != ck_user
4166 && convs->kind != ck_ambig
4167 && convs->kind != ck_ref_bind)
4169 conversion *t = convs;
4170 for (; t; t = convs->u.next)
4172 if (t->kind == ck_user || !t->bad_p)
4174 expr = convert_like_real (t, expr, fn, argnum, 1,
4175 /*issue_conversion_warnings=*/false,
4176 /*c_cast_p=*/false);
4179 else if (t->kind == ck_ambig)
4180 return convert_like_real (t, expr, fn, argnum, 1,
4181 /*issue_conversion_warnings=*/false,
4182 /*c_cast_p=*/false);
4183 else if (t->kind == ck_identity)
4186 pedwarn ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4188 pedwarn (" initializing argument %P of %qD", argnum, fn);
4189 return cp_convert (totype, expr);
4192 if (issue_conversion_warnings)
4194 tree t = non_reference (totype);
4196 /* Issue warnings about peculiar, but valid, uses of NULL. */
4197 if (ARITHMETIC_TYPE_P (t) && expr == null_node)
4200 warning (0, "passing NULL to non-pointer argument %P of %qD",
4203 warning (0, "converting to non-pointer type %qT from NULL", t);
4206 /* Warn about assigning a floating-point type to an integer type. */
4207 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
4208 && TREE_CODE (t) == INTEGER_TYPE)
4211 warning (0, "passing %qT for argument %P to %qD",
4212 TREE_TYPE (expr), argnum, fn);
4214 warning (0, "converting to %qT from %qT", t, TREE_TYPE (expr));
4218 switch (convs->kind)
4222 struct z_candidate *cand = convs->cand;
4223 tree convfn = cand->fn;
4226 if (DECL_CONSTRUCTOR_P (convfn))
4228 tree t = build_int_cst (build_pointer_type (DECL_CONTEXT (convfn)),
4231 args = build_tree_list (NULL_TREE, expr);
4232 /* We should never try to call the abstract or base constructor
4234 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (convfn)
4235 && !DECL_HAS_VTT_PARM_P (convfn));
4236 args = tree_cons (NULL_TREE, t, args);
4239 args = build_this (expr);
4240 expr = build_over_call (cand, LOOKUP_NORMAL);
4242 /* If this is a constructor or a function returning an aggr type,
4243 we need to build up a TARGET_EXPR. */
4244 if (DECL_CONSTRUCTOR_P (convfn))
4245 expr = build_cplus_new (totype, expr);
4247 /* The result of the call is then used to direct-initialize the object
4248 that is the destination of the copy-initialization. [dcl.init]
4250 Note that this step is not reflected in the conversion sequence;
4251 it affects the semantics when we actually perform the
4252 conversion, but is not considered during overload resolution.
4254 If the target is a class, that means call a ctor. */
4255 if (IS_AGGR_TYPE (totype)
4256 && (inner >= 0 || !lvalue_p (expr)))
4260 /* Core issue 84, now a DR, says that we don't
4261 allow UDCs for these args (which deliberately
4262 breaks copy-init of an auto_ptr<Base> from an
4263 auto_ptr<Derived>). */
4264 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4271 (" initializing argument %P of %qD from result of %qD",
4272 argnum, fn, convfn);
4275 (" initializing temporary from result of %qD", convfn);
4277 expr = build_cplus_new (totype, expr);
4282 if (type_unknown_p (expr))
4283 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4284 /* Convert a constant to its underlying value, unless we are
4285 about to bind it to a reference, in which case we need to
4286 leave it as an lvalue. */
4288 expr = decl_constant_value (expr);
4289 if (convs->check_copy_constructor_p)
4290 check_constructor_callable (totype, expr);
4293 /* Call build_user_type_conversion again for the error. */
4294 return build_user_type_conversion
4295 (totype, convs->u.expr, LOOKUP_NORMAL);
4301 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4302 convs->kind == ck_ref_bind ? -1 : 1,
4303 /*issue_conversion_warnings=*/false,
4305 if (expr == error_mark_node)
4306 return error_mark_node;
4308 switch (convs->kind)
4311 if (! IS_AGGR_TYPE (totype))
4313 /* Else fall through. */
4315 if (convs->kind == ck_base && !convs->need_temporary_p)
4317 /* We are going to bind a reference directly to a base-class
4318 subobject of EXPR. */
4319 if (convs->check_copy_constructor_p)
4320 check_constructor_callable (TREE_TYPE (expr), expr);
4321 /* Build an expression for `*((base*) &expr)'. */
4322 expr = build_unary_op (ADDR_EXPR, expr, 0);
4323 expr = convert_to_base (expr, build_pointer_type (totype),
4324 !c_cast_p, /*nonnull=*/true);
4325 expr = build_indirect_ref (expr, "implicit conversion");
4329 /* Copy-initialization where the cv-unqualified version of the source
4330 type is the same class as, or a derived class of, the class of the
4331 destination [is treated as direct-initialization]. [dcl.init] */
4332 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4334 if (diagnostic_fn && fn)
4335 diagnostic_fn (" initializing argument %P of %qD", argnum, fn);
4336 return build_cplus_new (totype, expr);
4340 tree ref_type = totype;
4342 /* If necessary, create a temporary. */
4343 if (convs->need_temporary_p || !lvalue_p (expr))
4345 tree type = convs->u.next->type;
4346 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4348 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4350 /* If the reference is volatile or non-const, we
4351 cannot create a temporary. */
4352 if (lvalue & clk_bitfield)
4353 error ("cannot bind bitfield %qE to %qT",
4355 else if (lvalue & clk_packed)
4356 error ("cannot bind packed field %qE to %qT",
4359 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4360 return error_mark_node;
4362 /* If the source is a packed field, and we must use a copy
4363 constructor, then building the target expr will require
4364 binding the field to the reference parameter to the
4365 copy constructor, and we'll end up with an infinite
4366 loop. If we can use a bitwise copy, then we'll be
4368 if ((lvalue & clk_packed)
4369 && CLASS_TYPE_P (type)
4370 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4372 error ("cannot bind packed field %qE to %qT",
4374 return error_mark_node;
4376 expr = build_target_expr_with_type (expr, type);
4379 /* Take the address of the thing to which we will bind the
4381 expr = build_unary_op (ADDR_EXPR, expr, 1);
4382 if (expr == error_mark_node)
4383 return error_mark_node;
4385 /* Convert it to a pointer to the type referred to by the
4386 reference. This will adjust the pointer if a derived to
4387 base conversion is being performed. */
4388 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4390 /* Convert the pointer to the desired reference type. */
4391 return build_nop (ref_type, expr);
4395 return decay_conversion (expr);
4398 /* Warn about deprecated conversion if appropriate. */
4399 string_conv_p (totype, expr, 1);
4404 expr = convert_to_base (expr, totype, !c_cast_p,
4406 return build_nop (totype, expr);
4409 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4416 if (issue_conversion_warnings)
4417 expr = convert_and_check (totype, expr);
4419 expr = convert (totype, expr);
4424 /* Build a call to __builtin_trap. */
4427 call_builtin_trap (void)
4429 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4431 gcc_assert (fn != NULL);
4432 fn = build_call (fn, NULL_TREE);
4436 /* ARG is being passed to a varargs function. Perform any conversions
4437 required. Return the converted value. */
4440 convert_arg_to_ellipsis (tree arg)
4444 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4445 standard conversions are performed. */
4446 arg = decay_conversion (arg);
4449 If the argument has integral or enumeration type that is subject
4450 to the integral promotions (_conv.prom_), or a floating point
4451 type that is subject to the floating point promotion
4452 (_conv.fpprom_), the value of the argument is converted to the
4453 promoted type before the call. */
4454 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4455 && (TYPE_PRECISION (TREE_TYPE (arg))
4456 < TYPE_PRECISION (double_type_node)))
4457 arg = convert_to_real (double_type_node, arg);
4458 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4459 arg = perform_integral_promotions (arg);
4461 arg = require_complete_type (arg);
4463 if (arg != error_mark_node
4464 && !pod_type_p (TREE_TYPE (arg)))
4466 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4467 here and do a bitwise copy, but now cp_expr_size will abort if we
4469 If the call appears in the context of a sizeof expression,
4470 there is no need to emit a warning, since the expression won't be
4471 evaluated. We keep the builtin_trap just as a safety check. */
4472 if (!skip_evaluation)
4473 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4474 "call will abort at runtime", TREE_TYPE (arg));
4475 arg = call_builtin_trap ();
4476 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4483 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4486 build_x_va_arg (tree expr, tree type)
4488 if (processing_template_decl)
4489 return build_min (VA_ARG_EXPR, type, expr);
4491 type = complete_type_or_else (type, NULL_TREE);
4493 if (expr == error_mark_node || !type)
4494 return error_mark_node;
4496 if (! pod_type_p (type))
4498 /* Undefined behavior [expr.call] 5.2.2/7. */
4499 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4500 "call will abort at runtime", type);
4501 expr = convert (build_pointer_type (type), null_node);
4502 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4503 call_builtin_trap (), expr);
4504 expr = build_indirect_ref (expr, NULL);
4508 return build_va_arg (expr, type);
4511 /* TYPE has been given to va_arg. Apply the default conversions which
4512 would have happened when passed via ellipsis. Return the promoted
4513 type, or the passed type if there is no change. */
4516 cxx_type_promotes_to (tree type)
4520 /* Perform the array-to-pointer and function-to-pointer
4522 type = type_decays_to (type);
4524 promote = type_promotes_to (type);
4525 if (same_type_p (type, promote))
4531 /* ARG is a default argument expression being passed to a parameter of
4532 the indicated TYPE, which is a parameter to FN. Do any required
4533 conversions. Return the converted value. */
4536 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4538 /* If the ARG is an unparsed default argument expression, the
4539 conversion cannot be performed. */
4540 if (TREE_CODE (arg) == DEFAULT_ARG)
4542 error ("the default argument for parameter %d of %qD has "
4543 "not yet been parsed",
4545 return error_mark_node;
4548 if (fn && DECL_TEMPLATE_INFO (fn))
4549 arg = tsubst_default_argument (fn, type, arg);
4551 arg = break_out_target_exprs (arg);
4553 if (TREE_CODE (arg) == CONSTRUCTOR)
4555 arg = digest_init (type, arg);
4556 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4557 "default argument", fn, parmnum);
4561 /* This could get clobbered by the following call. */
4562 if (TREE_HAS_CONSTRUCTOR (arg))
4563 arg = copy_node (arg);
4565 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4566 "default argument", fn, parmnum);
4567 arg = convert_for_arg_passing (type, arg);
4573 /* Returns the type which will really be used for passing an argument of
4577 type_passed_as (tree type)
4579 /* Pass classes with copy ctors by invisible reference. */
4580 if (TREE_ADDRESSABLE (type))
4582 type = build_reference_type (type);
4583 /* There are no other pointers to this temporary. */
4584 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4586 else if (targetm.calls.promote_prototypes (type)
4587 && INTEGRAL_TYPE_P (type)
4588 && COMPLETE_TYPE_P (type)
4589 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4590 TYPE_SIZE (integer_type_node)))
4591 type = integer_type_node;
4596 /* Actually perform the appropriate conversion. */
4599 convert_for_arg_passing (tree type, tree val)
4601 if (val == error_mark_node)
4603 /* Pass classes with copy ctors by invisible reference. */
4604 else if (TREE_ADDRESSABLE (type))
4605 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4606 else if (targetm.calls.promote_prototypes (type)
4607 && INTEGRAL_TYPE_P (type)
4608 && COMPLETE_TYPE_P (type)
4609 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4610 TYPE_SIZE (integer_type_node)))
4611 val = perform_integral_promotions (val);
4612 if (warn_missing_format_attribute)
4614 tree rhstype = TREE_TYPE (val);
4615 const enum tree_code coder = TREE_CODE (rhstype);
4616 const enum tree_code codel = TREE_CODE (type);
4617 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4619 && check_missing_format_attribute (type, rhstype))
4620 warning (OPT_Wmissing_format_attribute,
4621 "argument of function call might be a candidate for a format attribute");
4626 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4627 which no conversions at all should be done. This is true for some
4628 builtins which don't act like normal functions. */
4631 magic_varargs_p (tree fn)
4633 if (DECL_BUILT_IN (fn))
4634 switch (DECL_FUNCTION_CODE (fn))
4636 case BUILT_IN_CLASSIFY_TYPE:
4637 case BUILT_IN_CONSTANT_P:
4638 case BUILT_IN_NEXT_ARG:
4639 case BUILT_IN_STDARG_START:
4640 case BUILT_IN_VA_START:
4649 /* Subroutine of the various build_*_call functions. Overload resolution
4650 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4651 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4652 bitmask of various LOOKUP_* flags which apply to the call itself. */
4655 build_over_call (struct z_candidate *cand, int flags)
4658 tree args = cand->args;
4659 conversion **convs = cand->convs;
4661 tree converted_args = NULL_TREE;
4662 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4667 /* In a template, there is no need to perform all of the work that
4668 is normally done. We are only interested in the type of the call
4669 expression, i.e., the return type of the function. Any semantic
4670 errors will be deferred until the template is instantiated. */
4671 if (processing_template_decl)
4675 return_type = TREE_TYPE (TREE_TYPE (fn));
4676 expr = build3 (CALL_EXPR, return_type, fn, args, NULL_TREE);
4677 if (TREE_THIS_VOLATILE (fn) && cfun)
4678 current_function_returns_abnormally = 1;
4679 if (!VOID_TYPE_P (return_type))
4680 require_complete_type (return_type);
4681 return convert_from_reference (expr);
4684 /* Give any warnings we noticed during overload resolution. */
4687 struct candidate_warning *w;
4688 for (w = cand->warnings; w; w = w->next)
4689 joust (cand, w->loser, 1);
4692 if (DECL_FUNCTION_MEMBER_P (fn))
4694 /* If FN is a template function, two cases must be considered.
4699 template <class T> void f();
4701 template <class T> struct B {
4705 struct C : A, B<int> {
4707 using B<int>::g; // #2
4710 In case #1 where `A::f' is a member template, DECL_ACCESS is
4711 recorded in the primary template but not in its specialization.
4712 We check access of FN using its primary template.
4714 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4715 because it is a member of class template B, DECL_ACCESS is
4716 recorded in the specialization `B<int>::g'. We cannot use its
4717 primary template because `B<T>::g' and `B<int>::g' may have
4718 different access. */
4719 if (DECL_TEMPLATE_INFO (fn)
4720 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
4721 perform_or_defer_access_check (cand->access_path,
4722 DECL_TI_TEMPLATE (fn));
4724 perform_or_defer_access_check (cand->access_path, fn);
4727 if (args && TREE_CODE (args) != TREE_LIST)
4728 args = build_tree_list (NULL_TREE, args);
4731 /* The implicit parameters to a constructor are not considered by overload
4732 resolution, and must be of the proper type. */
4733 if (DECL_CONSTRUCTOR_P (fn))
4735 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4736 arg = TREE_CHAIN (arg);
4737 parm = TREE_CHAIN (parm);
4738 /* We should never try to call the abstract constructor. */
4739 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
4741 if (DECL_HAS_VTT_PARM_P (fn))
4743 converted_args = tree_cons
4744 (NULL_TREE, TREE_VALUE (arg), converted_args);
4745 arg = TREE_CHAIN (arg);
4746 parm = TREE_CHAIN (parm);
4749 /* Bypass access control for 'this' parameter. */
4750 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4752 tree parmtype = TREE_VALUE (parm);
4753 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4757 if (convs[i]->bad_p)
4758 pedwarn ("passing %qT as %<this%> argument of %q#D discards qualifiers",
4759 TREE_TYPE (argtype), fn);
4761 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4762 X is called for an object that is not of type X, or of a type
4763 derived from X, the behavior is undefined.
4765 So we can assume that anything passed as 'this' is non-null, and
4766 optimize accordingly. */
4767 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
4768 /* Convert to the base in which the function was declared. */
4769 gcc_assert (cand->conversion_path != NULL_TREE);
4770 converted_arg = build_base_path (PLUS_EXPR,
4772 cand->conversion_path,
4774 /* Check that the base class is accessible. */
4775 if (!accessible_base_p (TREE_TYPE (argtype),
4776 BINFO_TYPE (cand->conversion_path), true))
4777 error ("%qT is not an accessible base of %qT",
4778 BINFO_TYPE (cand->conversion_path),
4779 TREE_TYPE (argtype));
4780 /* If fn was found by a using declaration, the conversion path
4781 will be to the derived class, not the base declaring fn. We
4782 must convert from derived to base. */
4783 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4784 TREE_TYPE (parmtype), ba_unique, NULL);
4785 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4788 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4789 parm = TREE_CHAIN (parm);
4790 arg = TREE_CHAIN (arg);
4796 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4798 tree type = TREE_VALUE (parm);
4801 val = convert_like_with_context
4802 (conv, TREE_VALUE (arg), fn, i - is_method);
4804 val = convert_for_arg_passing (type, val);
4805 converted_args = tree_cons (NULL_TREE, val, converted_args);
4808 /* Default arguments */
4809 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4811 = tree_cons (NULL_TREE,
4812 convert_default_arg (TREE_VALUE (parm),
4813 TREE_PURPOSE (parm),
4818 for (; arg; arg = TREE_CHAIN (arg))
4820 tree a = TREE_VALUE (arg);
4821 if (magic_varargs_p (fn))
4822 /* Do no conversions for magic varargs. */;
4824 a = convert_arg_to_ellipsis (a);
4825 converted_args = tree_cons (NULL_TREE, a, converted_args);
4828 converted_args = nreverse (converted_args);
4830 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4831 converted_args, TYPE_ARG_TYPES (TREE_TYPE (fn)));
4833 /* Avoid actually calling copy constructors and copy assignment operators,
4836 if (! flag_elide_constructors)
4837 /* Do things the hard way. */;
4838 else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn))
4841 arg = skip_artificial_parms_for (fn, converted_args);
4842 arg = TREE_VALUE (arg);
4844 /* Pull out the real argument, disregarding const-correctness. */
4846 while (TREE_CODE (targ) == NOP_EXPR
4847 || TREE_CODE (targ) == NON_LVALUE_EXPR
4848 || TREE_CODE (targ) == CONVERT_EXPR)
4849 targ = TREE_OPERAND (targ, 0);
4850 if (TREE_CODE (targ) == ADDR_EXPR)
4852 targ = TREE_OPERAND (targ, 0);
4853 if (!same_type_ignoring_top_level_qualifiers_p
4854 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4863 arg = build_indirect_ref (arg, 0);
4865 /* [class.copy]: the copy constructor is implicitly defined even if
4866 the implementation elided its use. */
4867 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4870 /* If we're creating a temp and we already have one, don't create a
4871 new one. If we're not creating a temp but we get one, use
4872 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4873 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4874 temp or an INIT_EXPR otherwise. */
4875 if (integer_zerop (TREE_VALUE (args)))
4877 if (TREE_CODE (arg) == TARGET_EXPR)
4879 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4880 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4882 else if (TREE_CODE (arg) == TARGET_EXPR
4883 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4885 tree to = stabilize_reference
4886 (build_indirect_ref (TREE_VALUE (args), 0));
4888 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4892 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4894 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4896 tree to = stabilize_reference
4897 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4898 tree type = TREE_TYPE (to);
4899 tree as_base = CLASSTYPE_AS_BASE (type);
4901 arg = TREE_VALUE (TREE_CHAIN (converted_args));
4902 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
4904 arg = build_indirect_ref (arg, 0);
4905 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4909 /* We must only copy the non-tail padding parts.
4910 Use __builtin_memcpy for the bitwise copy. */
4914 args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL);
4915 args = tree_cons (NULL, arg, args);
4916 t = build_unary_op (ADDR_EXPR, to, 0);
4917 args = tree_cons (NULL, t, args);
4918 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
4919 t = build_call (t, args);
4921 t = convert (TREE_TYPE (TREE_VALUE (args)), t);
4922 val = build_indirect_ref (t, 0);
4930 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4932 tree t, *p = &TREE_VALUE (converted_args);
4933 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4936 gcc_assert (binfo && binfo != error_mark_node);
4938 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4939 if (TREE_SIDE_EFFECTS (*p))
4940 *p = save_expr (*p);
4941 t = build_pointer_type (TREE_TYPE (fn));
4942 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4943 fn = build_java_interface_fn_ref (fn, *p);
4945 fn = build_vfn_ref (*p, DECL_VINDEX (fn));
4948 else if (DECL_INLINE (fn))
4949 fn = inline_conversion (fn);
4951 fn = build_addr_func (fn);
4953 return build_cxx_call (fn, converted_args);
4956 /* Build and return a call to FN, using ARGS. This function performs
4957 no overload resolution, conversion, or other high-level
4961 build_cxx_call (tree fn, tree args)
4965 fn = build_call (fn, args);
4967 /* If this call might throw an exception, note that fact. */
4968 fndecl = get_callee_fndecl (fn);
4969 if ((!fndecl || !TREE_NOTHROW (fndecl))
4970 && at_function_scope_p ()
4972 cp_function_chain->can_throw = 1;
4974 /* Some built-in function calls will be evaluated at compile-time in
4976 fn = fold_if_not_in_template (fn);
4978 if (VOID_TYPE_P (TREE_TYPE (fn)))
4981 fn = require_complete_type (fn);
4982 if (fn == error_mark_node)
4983 return error_mark_node;
4985 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4986 fn = build_cplus_new (TREE_TYPE (fn), fn);
4987 return convert_from_reference (fn);
4990 static GTY(()) tree java_iface_lookup_fn;
4992 /* Make an expression which yields the address of the Java interface
4993 method FN. This is achieved by generating a call to libjava's
4994 _Jv_LookupInterfaceMethodIdx(). */
4997 build_java_interface_fn_ref (tree fn, tree instance)
4999 tree lookup_args, lookup_fn, method, idx;
5000 tree klass_ref, iface, iface_ref;
5003 if (!java_iface_lookup_fn)
5005 tree endlink = build_void_list_node ();
5006 tree t = tree_cons (NULL_TREE, ptr_type_node,
5007 tree_cons (NULL_TREE, ptr_type_node,
5008 tree_cons (NULL_TREE, java_int_type_node,
5010 java_iface_lookup_fn
5011 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
5012 build_function_type (ptr_type_node, t),
5013 0, NOT_BUILT_IN, NULL, NULL_TREE);
5016 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5017 This is the first entry in the vtable. */
5018 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
5021 /* Get the java.lang.Class pointer for the interface being called. */
5022 iface = DECL_CONTEXT (fn);
5023 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5024 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5025 || DECL_CONTEXT (iface_ref) != iface)
5027 error ("could not find class$ field in java interface type %qT",
5029 return error_mark_node;
5031 iface_ref = build_address (iface_ref);
5032 iface_ref = convert (build_pointer_type (iface), iface_ref);
5034 /* Determine the itable index of FN. */
5036 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5038 if (!DECL_VIRTUAL_P (method))
5044 idx = build_int_cst (NULL_TREE, i);
5046 lookup_args = tree_cons (NULL_TREE, klass_ref,
5047 tree_cons (NULL_TREE, iface_ref,
5048 build_tree_list (NULL_TREE, idx)));
5049 lookup_fn = build1 (ADDR_EXPR,
5050 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5051 java_iface_lookup_fn);
5052 return build3 (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
5055 /* Returns the value to use for the in-charge parameter when making a
5056 call to a function with the indicated NAME.
5058 FIXME:Can't we find a neater way to do this mapping? */
5061 in_charge_arg_for_name (tree name)
5063 if (name == base_ctor_identifier
5064 || name == base_dtor_identifier)
5065 return integer_zero_node;
5066 else if (name == complete_ctor_identifier)
5067 return integer_one_node;
5068 else if (name == complete_dtor_identifier)
5069 return integer_two_node;
5070 else if (name == deleting_dtor_identifier)
5071 return integer_three_node;
5073 /* This function should only be called with one of the names listed
5079 /* Build a call to a constructor, destructor, or an assignment
5080 operator for INSTANCE, an expression with class type. NAME
5081 indicates the special member function to call; ARGS are the
5082 arguments. BINFO indicates the base of INSTANCE that is to be
5083 passed as the `this' parameter to the member function called.
5085 FLAGS are the LOOKUP_* flags to use when processing the call.
5087 If NAME indicates a complete object constructor, INSTANCE may be
5088 NULL_TREE. In this case, the caller will call build_cplus_new to
5089 store the newly constructed object into a VAR_DECL. */
5092 build_special_member_call (tree instance, tree name, tree args,
5093 tree binfo, int flags)
5096 /* The type of the subobject to be constructed or destroyed. */
5099 gcc_assert (name == complete_ctor_identifier
5100 || name == base_ctor_identifier
5101 || name == complete_dtor_identifier
5102 || name == base_dtor_identifier
5103 || name == deleting_dtor_identifier
5104 || name == ansi_assopname (NOP_EXPR));
5107 /* Resolve the name. */
5108 if (!complete_type_or_else (binfo, NULL_TREE))
5109 return error_mark_node;
5111 binfo = TYPE_BINFO (binfo);
5114 gcc_assert (binfo != NULL_TREE);
5116 class_type = BINFO_TYPE (binfo);
5118 /* Handle the special case where INSTANCE is NULL_TREE. */
5119 if (name == complete_ctor_identifier && !instance)
5121 instance = build_int_cst (build_pointer_type (class_type), 0);
5122 instance = build1 (INDIRECT_REF, class_type, instance);
5126 if (name == complete_dtor_identifier
5127 || name == base_dtor_identifier
5128 || name == deleting_dtor_identifier)
5129 gcc_assert (args == NULL_TREE);
5131 /* Convert to the base class, if necessary. */
5132 if (!same_type_ignoring_top_level_qualifiers_p
5133 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5135 if (name != ansi_assopname (NOP_EXPR))
5136 /* For constructors and destructors, either the base is
5137 non-virtual, or it is virtual but we are doing the
5138 conversion from a constructor or destructor for the
5139 complete object. In either case, we can convert
5141 instance = convert_to_base_statically (instance, binfo);
5143 /* However, for assignment operators, we must convert
5144 dynamically if the base is virtual. */
5145 instance = build_base_path (PLUS_EXPR, instance,
5146 binfo, /*nonnull=*/1);
5150 gcc_assert (instance != NULL_TREE);
5152 fns = lookup_fnfields (binfo, name, 1);
5154 /* When making a call to a constructor or destructor for a subobject
5155 that uses virtual base classes, pass down a pointer to a VTT for
5157 if ((name == base_ctor_identifier
5158 || name == base_dtor_identifier)
5159 && CLASSTYPE_VBASECLASSES (class_type))
5164 /* If the current function is a complete object constructor
5165 or destructor, then we fetch the VTT directly.
5166 Otherwise, we look it up using the VTT we were given. */
5167 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5168 vtt = decay_conversion (vtt);
5169 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5170 build2 (EQ_EXPR, boolean_type_node,
5171 current_in_charge_parm, integer_zero_node),
5174 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5175 sub_vtt = build2 (PLUS_EXPR, TREE_TYPE (vtt), vtt,
5176 BINFO_SUBVTT_INDEX (binfo));
5178 args = tree_cons (NULL_TREE, sub_vtt, args);
5181 return build_new_method_call (instance, fns, args,
5182 TYPE_BINFO (BINFO_TYPE (binfo)),
5186 /* Return the NAME, as a C string. The NAME indicates a function that
5187 is a member of TYPE. *FREE_P is set to true if the caller must
5188 free the memory returned.
5190 Rather than go through all of this, we should simply set the names
5191 of constructors and destructors appropriately, and dispense with
5192 ctor_identifier, dtor_identifier, etc. */
5195 name_as_c_string (tree name, tree type, bool *free_p)
5199 /* Assume that we will not allocate memory. */
5201 /* Constructors and destructors are special. */
5202 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5205 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5206 /* For a destructor, add the '~'. */
5207 if (name == complete_dtor_identifier
5208 || name == base_dtor_identifier
5209 || name == deleting_dtor_identifier)
5211 pretty_name = concat ("~", pretty_name, NULL);
5212 /* Remember that we need to free the memory allocated. */
5216 else if (IDENTIFIER_TYPENAME_P (name))
5218 pretty_name = concat ("operator ",
5219 type_as_string (TREE_TYPE (name),
5220 TFF_PLAIN_IDENTIFIER),
5222 /* Remember that we need to free the memory allocated. */
5226 pretty_name = (char *) IDENTIFIER_POINTER (name);
5231 /* Build a call to "INSTANCE.FN (ARGS)". */
5234 build_new_method_call (tree instance, tree fns, tree args,
5235 tree conversion_path, int flags)
5237 struct z_candidate *candidates = 0, *cand;
5238 tree explicit_targs = NULL_TREE;
5239 tree basetype = NULL_TREE;
5242 tree mem_args = NULL_TREE, instance_ptr;
5248 int template_only = 0;
5255 gcc_assert (instance != NULL_TREE);
5257 if (error_operand_p (instance)
5258 || error_operand_p (fns)
5259 || args == error_mark_node)
5260 return error_mark_node;
5262 if (!BASELINK_P (fns))
5264 error ("call to non-function %qD", fns);
5265 return error_mark_node;
5268 orig_instance = instance;
5272 /* Dismantle the baselink to collect all the information we need. */
5273 if (!conversion_path)
5274 conversion_path = BASELINK_BINFO (fns);
5275 access_binfo = BASELINK_ACCESS_BINFO (fns);
5276 optype = BASELINK_OPTYPE (fns);
5277 fns = BASELINK_FUNCTIONS (fns);
5278 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5280 explicit_targs = TREE_OPERAND (fns, 1);
5281 fns = TREE_OPERAND (fns, 0);
5284 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5285 || TREE_CODE (fns) == TEMPLATE_DECL
5286 || TREE_CODE (fns) == OVERLOAD);
5287 fn = get_first_fn (fns);
5288 name = DECL_NAME (fn);
5290 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5291 gcc_assert (CLASS_TYPE_P (basetype));
5293 if (processing_template_decl)
5295 instance = build_non_dependent_expr (instance);
5296 args = build_non_dependent_args (orig_args);
5299 /* The USER_ARGS are the arguments we will display to users if an
5300 error occurs. The USER_ARGS should not include any
5301 compiler-generated arguments. The "this" pointer hasn't been
5302 added yet. However, we must remove the VTT pointer if this is a
5303 call to a base-class constructor or destructor. */
5305 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5307 /* Callers should explicitly indicate whether they want to construct
5308 the complete object or just the part without virtual bases. */
5309 gcc_assert (name != ctor_identifier);
5310 /* Similarly for destructors. */
5311 gcc_assert (name != dtor_identifier);
5312 /* Remove the VTT pointer, if present. */
5313 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5314 && CLASSTYPE_VBASECLASSES (basetype))
5315 user_args = TREE_CHAIN (user_args);
5318 /* Process the argument list. */
5319 args = resolve_args (args);
5320 if (args == error_mark_node)
5321 return error_mark_node;
5323 instance_ptr = build_this (instance);
5325 /* It's OK to call destructors on cv-qualified objects. Therefore,
5326 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5327 if (DECL_DESTRUCTOR_P (fn))
5329 tree type = build_pointer_type (basetype);
5330 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5331 instance_ptr = build_nop (type, instance_ptr);
5332 name = complete_dtor_identifier;
5335 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5336 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5338 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5339 p = conversion_obstack_alloc (0);
5341 for (fn = fns; fn; fn = OVL_NEXT (fn))
5343 tree t = OVL_CURRENT (fn);
5346 /* We can end up here for copy-init of same or base class. */
5347 if ((flags & LOOKUP_ONLYCONVERTING)
5348 && DECL_NONCONVERTING_P (t))
5351 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5352 this_arglist = mem_args;
5354 this_arglist = args;
5356 if (TREE_CODE (t) == TEMPLATE_DECL)
5357 /* A member template. */
5358 add_template_candidate (&candidates, t,
5361 this_arglist, optype,
5366 else if (! template_only)
5367 add_function_candidate (&candidates, t,
5375 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5378 if (!COMPLETE_TYPE_P (basetype))
5379 cxx_incomplete_type_error (instance_ptr, basetype);
5385 pretty_name = name_as_c_string (name, basetype, &free_p);
5386 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5387 basetype, pretty_name, user_args,
5388 TREE_TYPE (TREE_TYPE (instance_ptr)));
5392 print_z_candidates (candidates);
5393 call = error_mark_node;
5397 cand = tourney (candidates);
5403 pretty_name = name_as_c_string (name, basetype, &free_p);
5404 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5406 print_z_candidates (candidates);
5409 call = error_mark_node;
5413 if (!(flags & LOOKUP_NONVIRTUAL)
5414 && DECL_PURE_VIRTUAL_P (cand->fn)
5415 && instance == current_class_ref
5416 && (DECL_CONSTRUCTOR_P (current_function_decl)
5417 || DECL_DESTRUCTOR_P (current_function_decl)))
5418 /* This is not an error, it is runtime undefined
5420 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5421 "abstract virtual %q#D called from constructor"
5422 : "abstract virtual %q#D called from destructor"),
5425 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5426 && is_dummy_object (instance_ptr))
5428 error ("cannot call member function %qD without object",
5430 call = error_mark_node;
5434 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5435 && resolves_to_fixed_type_p (instance, 0))
5436 flags |= LOOKUP_NONVIRTUAL;
5438 call = build_over_call (cand, flags);
5440 /* In an expression of the form `a->f()' where `f' turns
5441 out to be a static member function, `a' is
5442 none-the-less evaluated. */
5443 if (TREE_CODE (TREE_TYPE (cand->fn)) != METHOD_TYPE
5444 && !is_dummy_object (instance_ptr)
5445 && TREE_SIDE_EFFECTS (instance))
5446 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5452 if (processing_template_decl && call != error_mark_node)
5453 call = (build_min_non_dep
5455 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5456 orig_args, NULL_TREE));
5458 /* Free all the conversions we allocated. */
5459 obstack_free (&conversion_obstack, p);
5464 /* Returns true iff standard conversion sequence ICS1 is a proper
5465 subsequence of ICS2. */
5468 is_subseq (conversion *ics1, conversion *ics2)
5470 /* We can assume that a conversion of the same code
5471 between the same types indicates a subsequence since we only get
5472 here if the types we are converting from are the same. */
5474 while (ics1->kind == ck_rvalue
5475 || ics1->kind == ck_lvalue)
5476 ics1 = ics1->u.next;
5480 while (ics2->kind == ck_rvalue
5481 || ics2->kind == ck_lvalue)
5482 ics2 = ics2->u.next;
5484 if (ics2->kind == ck_user
5485 || ics2->kind == ck_ambig
5486 || ics2->kind == ck_identity)
5487 /* At this point, ICS1 cannot be a proper subsequence of
5488 ICS2. We can get a USER_CONV when we are comparing the
5489 second standard conversion sequence of two user conversion
5493 ics2 = ics2->u.next;
5495 if (ics2->kind == ics1->kind
5496 && same_type_p (ics2->type, ics1->type)
5497 && same_type_p (ics2->u.next->type,
5498 ics1->u.next->type))
5503 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5504 be any _TYPE nodes. */
5507 is_properly_derived_from (tree derived, tree base)
5509 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5510 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5513 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5514 considers every class derived from itself. */
5515 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5516 && DERIVED_FROM_P (base, derived));
5519 /* We build the ICS for an implicit object parameter as a pointer
5520 conversion sequence. However, such a sequence should be compared
5521 as if it were a reference conversion sequence. If ICS is the
5522 implicit conversion sequence for an implicit object parameter,
5523 modify it accordingly. */
5526 maybe_handle_implicit_object (conversion **ics)
5530 /* [over.match.funcs]
5532 For non-static member functions, the type of the
5533 implicit object parameter is "reference to cv X"
5534 where X is the class of which the function is a
5535 member and cv is the cv-qualification on the member
5536 function declaration. */
5537 conversion *t = *ics;
5538 tree reference_type;
5540 /* The `this' parameter is a pointer to a class type. Make the
5541 implicit conversion talk about a reference to that same class
5543 reference_type = TREE_TYPE (t->type);
5544 reference_type = build_reference_type (reference_type);
5546 if (t->kind == ck_qual)
5548 if (t->kind == ck_ptr)
5550 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5551 t = direct_reference_binding (reference_type, t);
5556 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5557 and return the type to which the reference refers. Otherwise,
5558 leave *ICS unchanged and return NULL_TREE. */
5561 maybe_handle_ref_bind (conversion **ics)
5563 if ((*ics)->kind == ck_ref_bind)
5565 conversion *old_ics = *ics;
5566 tree type = TREE_TYPE (old_ics->type);
5567 *ics = old_ics->u.next;
5568 (*ics)->user_conv_p = old_ics->user_conv_p;
5569 (*ics)->bad_p = old_ics->bad_p;
5576 /* Compare two implicit conversion sequences according to the rules set out in
5577 [over.ics.rank]. Return values:
5579 1: ics1 is better than ics2
5580 -1: ics2 is better than ics1
5581 0: ics1 and ics2 are indistinguishable */
5584 compare_ics (conversion *ics1, conversion *ics2)
5590 tree deref_from_type1 = NULL_TREE;
5591 tree deref_from_type2 = NULL_TREE;
5592 tree deref_to_type1 = NULL_TREE;
5593 tree deref_to_type2 = NULL_TREE;
5594 conversion_rank rank1, rank2;
5596 /* REF_BINDING is nonzero if the result of the conversion sequence
5597 is a reference type. In that case TARGET_TYPE is the
5598 type referred to by the reference. */
5602 /* Handle implicit object parameters. */
5603 maybe_handle_implicit_object (&ics1);
5604 maybe_handle_implicit_object (&ics2);
5606 /* Handle reference parameters. */
5607 target_type1 = maybe_handle_ref_bind (&ics1);
5608 target_type2 = maybe_handle_ref_bind (&ics2);
5612 When comparing the basic forms of implicit conversion sequences (as
5613 defined in _over.best.ics_)
5615 --a standard conversion sequence (_over.ics.scs_) is a better
5616 conversion sequence than a user-defined conversion sequence
5617 or an ellipsis conversion sequence, and
5619 --a user-defined conversion sequence (_over.ics.user_) is a
5620 better conversion sequence than an ellipsis conversion sequence
5621 (_over.ics.ellipsis_). */
5622 rank1 = CONVERSION_RANK (ics1);
5623 rank2 = CONVERSION_RANK (ics2);
5627 else if (rank1 < rank2)
5630 if (rank1 == cr_bad)
5632 /* XXX Isn't this an extension? */
5633 /* Both ICS are bad. We try to make a decision based on what
5634 would have happened if they'd been good. */
5635 if (ics1->user_conv_p > ics2->user_conv_p
5636 || ics1->rank > ics2->rank)
5638 else if (ics1->user_conv_p < ics2->user_conv_p
5639 || ics1->rank < ics2->rank)
5642 /* We couldn't make up our minds; try to figure it out below. */
5645 if (ics1->ellipsis_p)
5646 /* Both conversions are ellipsis conversions. */
5649 /* User-defined conversion sequence U1 is a better conversion sequence
5650 than another user-defined conversion sequence U2 if they contain the
5651 same user-defined conversion operator or constructor and if the sec-
5652 ond standard conversion sequence of U1 is better than the second
5653 standard conversion sequence of U2. */
5655 if (ics1->user_conv_p)
5660 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5661 if (t1->kind == ck_ambig)
5663 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5664 if (t2->kind == ck_ambig)
5667 if (t1->cand->fn != t2->cand->fn)
5670 /* We can just fall through here, after setting up
5671 FROM_TYPE1 and FROM_TYPE2. */
5672 from_type1 = t1->type;
5673 from_type2 = t2->type;
5680 /* We're dealing with two standard conversion sequences.
5684 Standard conversion sequence S1 is a better conversion
5685 sequence than standard conversion sequence S2 if
5687 --S1 is a proper subsequence of S2 (comparing the conversion
5688 sequences in the canonical form defined by _over.ics.scs_,
5689 excluding any Lvalue Transformation; the identity
5690 conversion sequence is considered to be a subsequence of
5691 any non-identity conversion sequence */
5694 while (t1->kind != ck_identity)
5696 from_type1 = t1->type;
5699 while (t2->kind != ck_identity)
5701 from_type2 = t2->type;
5704 if (same_type_p (from_type1, from_type2))
5706 if (is_subseq (ics1, ics2))
5708 if (is_subseq (ics2, ics1))
5711 /* Otherwise, one sequence cannot be a subsequence of the other; they
5712 don't start with the same type. This can happen when comparing the
5713 second standard conversion sequence in two user-defined conversion
5720 --the rank of S1 is better than the rank of S2 (by the rules
5723 Standard conversion sequences are ordered by their ranks: an Exact
5724 Match is a better conversion than a Promotion, which is a better
5725 conversion than a Conversion.
5727 Two conversion sequences with the same rank are indistinguishable
5728 unless one of the following rules applies:
5730 --A conversion that is not a conversion of a pointer, or pointer
5731 to member, to bool is better than another conversion that is such
5734 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5735 so that we do not have to check it explicitly. */
5736 if (ics1->rank < ics2->rank)
5738 else if (ics2->rank < ics1->rank)
5741 to_type1 = ics1->type;
5742 to_type2 = ics2->type;
5744 if (TYPE_PTR_P (from_type1)
5745 && TYPE_PTR_P (from_type2)
5746 && TYPE_PTR_P (to_type1)
5747 && TYPE_PTR_P (to_type2))
5749 deref_from_type1 = TREE_TYPE (from_type1);
5750 deref_from_type2 = TREE_TYPE (from_type2);
5751 deref_to_type1 = TREE_TYPE (to_type1);
5752 deref_to_type2 = TREE_TYPE (to_type2);
5754 /* The rules for pointers to members A::* are just like the rules
5755 for pointers A*, except opposite: if B is derived from A then
5756 A::* converts to B::*, not vice versa. For that reason, we
5757 switch the from_ and to_ variables here. */
5758 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5759 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5760 || (TYPE_PTRMEMFUNC_P (from_type1)
5761 && TYPE_PTRMEMFUNC_P (from_type2)
5762 && TYPE_PTRMEMFUNC_P (to_type1)
5763 && TYPE_PTRMEMFUNC_P (to_type2)))
5765 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5766 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5767 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5768 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5771 if (deref_from_type1 != NULL_TREE
5772 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5773 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5775 /* This was one of the pointer or pointer-like conversions.
5779 --If class B is derived directly or indirectly from class A,
5780 conversion of B* to A* is better than conversion of B* to
5781 void*, and conversion of A* to void* is better than
5782 conversion of B* to void*. */
5783 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5784 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5786 if (is_properly_derived_from (deref_from_type1,
5789 else if (is_properly_derived_from (deref_from_type2,
5793 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5794 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5796 if (same_type_p (deref_from_type1, deref_from_type2))
5798 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5800 if (is_properly_derived_from (deref_from_type1,
5804 /* We know that DEREF_TO_TYPE1 is `void' here. */
5805 else if (is_properly_derived_from (deref_from_type1,
5810 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5811 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5815 --If class B is derived directly or indirectly from class A
5816 and class C is derived directly or indirectly from B,
5818 --conversion of C* to B* is better than conversion of C* to
5821 --conversion of B* to A* is better than conversion of C* to
5823 if (same_type_p (deref_from_type1, deref_from_type2))
5825 if (is_properly_derived_from (deref_to_type1,
5828 else if (is_properly_derived_from (deref_to_type2,
5832 else if (same_type_p (deref_to_type1, deref_to_type2))
5834 if (is_properly_derived_from (deref_from_type2,
5837 else if (is_properly_derived_from (deref_from_type1,
5843 else if (CLASS_TYPE_P (non_reference (from_type1))
5844 && same_type_p (from_type1, from_type2))
5846 tree from = non_reference (from_type1);
5850 --binding of an expression of type C to a reference of type
5851 B& is better than binding an expression of type C to a
5852 reference of type A&
5854 --conversion of C to B is better than conversion of C to A, */
5855 if (is_properly_derived_from (from, to_type1)
5856 && is_properly_derived_from (from, to_type2))
5858 if (is_properly_derived_from (to_type1, to_type2))
5860 else if (is_properly_derived_from (to_type2, to_type1))
5864 else if (CLASS_TYPE_P (non_reference (to_type1))
5865 && same_type_p (to_type1, to_type2))
5867 tree to = non_reference (to_type1);
5871 --binding of an expression of type B to a reference of type
5872 A& is better than binding an expression of type C to a
5873 reference of type A&,
5875 --conversion of B to A is better than conversion of C to A */
5876 if (is_properly_derived_from (from_type1, to)
5877 && is_properly_derived_from (from_type2, to))
5879 if (is_properly_derived_from (from_type2, from_type1))
5881 else if (is_properly_derived_from (from_type1, from_type2))
5888 --S1 and S2 differ only in their qualification conversion and yield
5889 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5890 qualification signature of type T1 is a proper subset of the cv-
5891 qualification signature of type T2 */
5892 if (ics1->kind == ck_qual
5893 && ics2->kind == ck_qual
5894 && same_type_p (from_type1, from_type2))
5895 return comp_cv_qual_signature (to_type1, to_type2);
5899 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5900 types to which the references refer are the same type except for
5901 top-level cv-qualifiers, and the type to which the reference
5902 initialized by S2 refers is more cv-qualified than the type to
5903 which the reference initialized by S1 refers */
5905 if (target_type1 && target_type2
5906 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5907 return comp_cv_qualification (target_type2, target_type1);
5909 /* Neither conversion sequence is better than the other. */
5913 /* The source type for this standard conversion sequence. */
5916 source_type (conversion *t)
5918 for (;; t = t->u.next)
5920 if (t->kind == ck_user
5921 || t->kind == ck_ambig
5922 || t->kind == ck_identity)
5928 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5929 a pointer to LOSER and re-running joust to produce the warning if WINNER
5930 is actually used. */
5933 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5935 candidate_warning *cw;
5937 cw = conversion_obstack_alloc (sizeof (candidate_warning));
5939 cw->next = winner->warnings;
5940 winner->warnings = cw;
5943 /* Compare two candidates for overloading as described in
5944 [over.match.best]. Return values:
5946 1: cand1 is better than cand2
5947 -1: cand2 is better than cand1
5948 0: cand1 and cand2 are indistinguishable */
5951 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5954 int off1 = 0, off2 = 0;
5958 /* Candidates that involve bad conversions are always worse than those
5960 if (cand1->viable > cand2->viable)
5962 if (cand1->viable < cand2->viable)
5965 /* If we have two pseudo-candidates for conversions to the same type,
5966 or two candidates for the same function, arbitrarily pick one. */
5967 if (cand1->fn == cand2->fn
5968 && (IS_TYPE_OR_DECL_P (cand1->fn)))
5971 /* a viable function F1
5972 is defined to be a better function than another viable function F2 if
5973 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5974 ICSi(F2), and then */
5976 /* for some argument j, ICSj(F1) is a better conversion sequence than
5979 /* For comparing static and non-static member functions, we ignore
5980 the implicit object parameter of the non-static function. The
5981 standard says to pretend that the static function has an object
5982 parm, but that won't work with operator overloading. */
5983 len = cand1->num_convs;
5984 if (len != cand2->num_convs)
5986 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
5987 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
5989 gcc_assert (static_1 != static_2);
6000 for (i = 0; i < len; ++i)
6002 conversion *t1 = cand1->convs[i + off1];
6003 conversion *t2 = cand2->convs[i + off2];
6004 int comp = compare_ics (t1, t2);
6009 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6010 == cr_std + cr_promotion)
6011 && t1->kind == ck_std
6012 && t2->kind == ck_std
6013 && TREE_CODE (t1->type) == INTEGER_TYPE
6014 && TREE_CODE (t2->type) == INTEGER_TYPE
6015 && (TYPE_PRECISION (t1->type)
6016 == TYPE_PRECISION (t2->type))
6017 && (TYPE_UNSIGNED (t1->u.next->type)
6018 || (TREE_CODE (t1->u.next->type)
6021 tree type = t1->u.next->type;
6023 struct z_candidate *w, *l;
6025 type1 = t1->type, type2 = t2->type,
6026 w = cand1, l = cand2;
6028 type1 = t2->type, type2 = t1->type,
6029 w = cand2, l = cand1;
6033 warning (0, "passing %qT chooses %qT over %qT",
6034 type, type1, type2);
6035 warning (0, " in call to %qD", w->fn);
6041 if (winner && comp != winner)
6050 /* warn about confusing overload resolution for user-defined conversions,
6051 either between a constructor and a conversion op, or between two
6053 if (winner && warn_conversion && cand1->second_conv
6054 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6055 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6057 struct z_candidate *w, *l;
6058 bool give_warning = false;
6061 w = cand1, l = cand2;
6063 w = cand2, l = cand1;
6065 /* We don't want to complain about `X::operator T1 ()'
6066 beating `X::operator T2 () const', when T2 is a no less
6067 cv-qualified version of T1. */
6068 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6069 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6071 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6072 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6074 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6079 if (!comp_ptr_ttypes (t, f))
6080 give_warning = true;
6083 give_warning = true;
6089 tree source = source_type (w->convs[0]);
6090 if (! DECL_CONSTRUCTOR_P (w->fn))
6091 source = TREE_TYPE (source);
6092 warning (0, "choosing %qD over %qD", w->fn, l->fn);
6093 warning (0, " for conversion from %qT to %qT",
6094 source, w->second_conv->type);
6095 warning (0, " because conversion sequence for the argument is better");
6105 F1 is a non-template function and F2 is a template function
6108 if (!cand1->template_decl && cand2->template_decl)
6110 else if (cand1->template_decl && !cand2->template_decl)
6114 F1 and F2 are template functions and the function template for F1 is
6115 more specialized than the template for F2 according to the partial
6118 if (cand1->template_decl && cand2->template_decl)
6120 winner = more_specialized_fn
6121 (TI_TEMPLATE (cand1->template_decl),
6122 TI_TEMPLATE (cand2->template_decl),
6123 /* [temp.func.order]: The presence of unused ellipsis and default
6124 arguments has no effect on the partial ordering of function
6125 templates. add_function_candidate() will not have
6126 counted the "this" argument for constructors. */
6127 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6133 the context is an initialization by user-defined conversion (see
6134 _dcl.init_ and _over.match.user_) and the standard conversion
6135 sequence from the return type of F1 to the destination type (i.e.,
6136 the type of the entity being initialized) is a better conversion
6137 sequence than the standard conversion sequence from the return type
6138 of F2 to the destination type. */
6140 if (cand1->second_conv)
6142 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6147 /* Check whether we can discard a builtin candidate, either because we
6148 have two identical ones or matching builtin and non-builtin candidates.
6150 (Pedantically in the latter case the builtin which matched the user
6151 function should not be added to the overload set, but we spot it here.
6154 ... the builtin candidates include ...
6155 - do not have the same parameter type list as any non-template
6156 non-member candidate. */
6158 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6159 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6161 for (i = 0; i < len; ++i)
6162 if (!same_type_p (cand1->convs[i]->type,
6163 cand2->convs[i]->type))
6165 if (i == cand1->num_convs)
6167 if (cand1->fn == cand2->fn)
6168 /* Two built-in candidates; arbitrarily pick one. */
6170 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6171 /* cand1 is built-in; prefer cand2. */
6174 /* cand2 is built-in; prefer cand1. */
6179 /* If the two functions are the same (this can happen with declarations
6180 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6181 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6182 && equal_functions (cand1->fn, cand2->fn))
6187 /* Extension: If the worst conversion for one candidate is worse than the
6188 worst conversion for the other, take the first. */
6191 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6192 struct z_candidate *w = 0, *l = 0;
6194 for (i = 0; i < len; ++i)
6196 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6197 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6198 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6199 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6202 winner = 1, w = cand1, l = cand2;
6204 winner = -1, w = cand2, l = cand1;
6210 ISO C++ says that these are ambiguous, even \
6211 though the worst conversion for the first is better than \
6212 the worst conversion for the second:");
6213 print_z_candidate (_("candidate 1:"), w);
6214 print_z_candidate (_("candidate 2:"), l);
6222 gcc_assert (!winner);
6226 /* Given a list of candidates for overloading, find the best one, if any.
6227 This algorithm has a worst case of O(2n) (winner is last), and a best
6228 case of O(n/2) (totally ambiguous); much better than a sorting
6231 static struct z_candidate *
6232 tourney (struct z_candidate *candidates)
6234 struct z_candidate *champ = candidates, *challenger;
6236 int champ_compared_to_predecessor = 0;
6238 /* Walk through the list once, comparing each current champ to the next
6239 candidate, knocking out a candidate or two with each comparison. */
6241 for (challenger = champ->next; challenger; )
6243 fate = joust (champ, challenger, 0);
6245 challenger = challenger->next;
6250 champ = challenger->next;
6253 champ_compared_to_predecessor = 0;
6258 champ_compared_to_predecessor = 1;
6261 challenger = champ->next;
6265 /* Make sure the champ is better than all the candidates it hasn't yet
6266 been compared to. */
6268 for (challenger = candidates;
6270 && !(champ_compared_to_predecessor && challenger->next == champ);
6271 challenger = challenger->next)
6273 fate = joust (champ, challenger, 0);
6281 /* Returns nonzero if things of type FROM can be converted to TO. */
6284 can_convert (tree to, tree from)
6286 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6289 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6292 can_convert_arg (tree to, tree from, tree arg, int flags)
6298 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6299 p = conversion_obstack_alloc (0);
6301 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6303 ok_p = (t && !t->bad_p);
6305 /* Free all the conversions we allocated. */
6306 obstack_free (&conversion_obstack, p);
6311 /* Like can_convert_arg, but allows dubious conversions as well. */
6314 can_convert_arg_bad (tree to, tree from, tree arg)
6319 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6320 p = conversion_obstack_alloc (0);
6321 /* Try to perform the conversion. */
6322 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6324 /* Free all the conversions we allocated. */
6325 obstack_free (&conversion_obstack, p);
6330 /* Convert EXPR to TYPE. Return the converted expression.
6332 Note that we allow bad conversions here because by the time we get to
6333 this point we are committed to doing the conversion. If we end up
6334 doing a bad conversion, convert_like will complain. */
6337 perform_implicit_conversion (tree type, tree expr)
6342 if (error_operand_p (expr))
6343 return error_mark_node;
6345 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6346 p = conversion_obstack_alloc (0);
6348 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6353 error ("could not convert %qE to %qT", expr, type);
6354 expr = error_mark_node;
6357 expr = convert_like (conv, expr);
6359 /* Free all the conversions we allocated. */
6360 obstack_free (&conversion_obstack, p);
6365 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6366 permitted. If the conversion is valid, the converted expression is
6367 returned. Otherwise, NULL_TREE is returned, except in the case
6368 that TYPE is a class type; in that case, an error is issued. If
6369 C_CAST_P is true, then this direction initialization is taking
6370 place as part of a static_cast being attempted as part of a C-style
6374 perform_direct_initialization_if_possible (tree type,
6381 if (type == error_mark_node || error_operand_p (expr))
6382 return error_mark_node;
6385 If the destination type is a (possibly cv-qualified) class type:
6387 -- If the initialization is direct-initialization ...,
6388 constructors are considered. ... If no constructor applies, or
6389 the overload resolution is ambiguous, the initialization is
6391 if (CLASS_TYPE_P (type))
6393 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6394 build_tree_list (NULL_TREE, expr),
6395 type, LOOKUP_NORMAL);
6396 return build_cplus_new (type, expr);
6399 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6400 p = conversion_obstack_alloc (0);
6402 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6405 if (!conv || conv->bad_p)
6408 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6409 /*issue_conversion_warnings=*/false,
6412 /* Free all the conversions we allocated. */
6413 obstack_free (&conversion_obstack, p);
6418 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6419 is being bound to a temporary. Create and return a new VAR_DECL
6420 with the indicated TYPE; this variable will store the value to
6421 which the reference is bound. */
6424 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6428 /* Create the variable. */
6429 var = create_temporary_var (type);
6431 /* Register the variable. */
6432 if (TREE_STATIC (decl))
6434 /* Namespace-scope or local static; give it a mangled name. */
6437 TREE_STATIC (var) = 1;
6438 name = mangle_ref_init_variable (decl);
6439 DECL_NAME (var) = name;
6440 SET_DECL_ASSEMBLER_NAME (var, name);
6441 var = pushdecl_top_level (var);
6444 /* Create a new cleanup level if necessary. */
6445 maybe_push_cleanup_level (type);
6450 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6451 initializing a variable of that TYPE. If DECL is non-NULL, it is
6452 the VAR_DECL being initialized with the EXPR. (In that case, the
6453 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6454 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6455 return, if *CLEANUP is no longer NULL, it will be an expression
6456 that should be pushed as a cleanup after the returned expression
6457 is used to initialize DECL.
6459 Return the converted expression. */
6462 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6467 if (type == error_mark_node || error_operand_p (expr))
6468 return error_mark_node;
6470 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6471 p = conversion_obstack_alloc (0);
6473 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6474 if (!conv || conv->bad_p)
6476 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6477 && !real_lvalue_p (expr))
6478 error ("invalid initialization of non-const reference of "
6479 "type %qT from a temporary of type %qT",
6480 type, TREE_TYPE (expr));
6482 error ("invalid initialization of reference of type "
6483 "%qT from expression of type %qT", type,
6485 return error_mark_node;
6488 /* If DECL is non-NULL, then this special rule applies:
6492 The temporary to which the reference is bound or the temporary
6493 that is the complete object to which the reference is bound
6494 persists for the lifetime of the reference.
6496 The temporaries created during the evaluation of the expression
6497 initializing the reference, except the temporary to which the
6498 reference is bound, are destroyed at the end of the
6499 full-expression in which they are created.
6501 In that case, we store the converted expression into a new
6502 VAR_DECL in a new scope.
6504 However, we want to be careful not to create temporaries when
6505 they are not required. For example, given:
6508 struct D : public B {};
6512 there is no need to copy the return value from "f"; we can just
6513 extend its lifetime. Similarly, given:
6516 struct T { operator S(); };
6520 we can extend the lifetime of the return value of the conversion
6522 gcc_assert (conv->kind == ck_ref_bind);
6526 tree base_conv_type;
6528 /* Skip over the REF_BIND. */
6529 conv = conv->u.next;
6530 /* If the next conversion is a BASE_CONV, skip that too -- but
6531 remember that the conversion was required. */
6532 if (conv->kind == ck_base)
6534 if (conv->check_copy_constructor_p)
6535 check_constructor_callable (TREE_TYPE (expr), expr);
6536 base_conv_type = conv->type;
6537 conv = conv->u.next;
6540 base_conv_type = NULL_TREE;
6541 /* Perform the remainder of the conversion. */
6542 expr = convert_like_real (conv, expr,
6543 /*fn=*/NULL_TREE, /*argnum=*/0,
6545 /*issue_conversion_warnings=*/true,
6546 /*c_cast_p=*/false);
6547 if (error_operand_p (expr))
6548 expr = error_mark_node;
6551 if (!real_lvalue_p (expr))
6556 /* Create the temporary variable. */
6557 type = TREE_TYPE (expr);
6558 var = make_temporary_var_for_ref_to_temp (decl, type);
6559 layout_decl (var, 0);
6560 /* If the rvalue is the result of a function call it will be
6561 a TARGET_EXPR. If it is some other construct (such as a
6562 member access expression where the underlying object is
6563 itself the result of a function call), turn it into a
6564 TARGET_EXPR here. It is important that EXPR be a
6565 TARGET_EXPR below since otherwise the INIT_EXPR will
6566 attempt to make a bitwise copy of EXPR to initialize
6568 if (TREE_CODE (expr) != TARGET_EXPR)
6569 expr = get_target_expr (expr);
6570 /* Create the INIT_EXPR that will initialize the temporary
6572 init = build2 (INIT_EXPR, type, var, expr);
6573 if (at_function_scope_p ())
6575 add_decl_expr (var);
6576 *cleanup = cxx_maybe_build_cleanup (var);
6578 /* We must be careful to destroy the temporary only
6579 after its initialization has taken place. If the
6580 initialization throws an exception, then the
6581 destructor should not be run. We cannot simply
6582 transform INIT into something like:
6584 (INIT, ({ CLEANUP_STMT; }))
6586 because emit_local_var always treats the
6587 initializer as a full-expression. Thus, the
6588 destructor would run too early; it would run at the
6589 end of initializing the reference variable, rather
6590 than at the end of the block enclosing the
6593 The solution is to pass back a cleanup expression
6594 which the caller is responsible for attaching to
6595 the statement tree. */
6599 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
6600 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6601 static_aggregates = tree_cons (NULL_TREE, var,
6604 /* Use its address to initialize the reference variable. */
6605 expr = build_address (var);
6607 expr = convert_to_base (expr,
6608 build_pointer_type (base_conv_type),
6609 /*check_access=*/true,
6611 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6614 /* Take the address of EXPR. */
6615 expr = build_unary_op (ADDR_EXPR, expr, 0);
6616 /* If a BASE_CONV was required, perform it now. */
6618 expr = (perform_implicit_conversion
6619 (build_pointer_type (base_conv_type), expr));
6620 expr = build_nop (type, expr);
6624 /* Perform the conversion. */
6625 expr = convert_like (conv, expr);
6627 /* Free all the conversions we allocated. */
6628 obstack_free (&conversion_obstack, p);
6633 #include "gt-cp-call.h"