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, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com) and
6 modified by Brendan Kehoe (brendan@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
25 /* High-level class interface. */
29 #include "coretypes.h"
38 #include "diagnostic.h"
42 #include "langhooks.h"
44 /* The various kinds of conversion. */
46 typedef enum conversion_kind {
62 /* The rank of the conversion. Order of the enumerals matters; better
63 conversions should come earlier in the list. */
65 typedef enum conversion_rank {
76 /* An implicit conversion sequence, in the sense of [over.best.ics].
77 The first conversion to be performed is at the end of the chain.
78 That conversion is always a cr_identity conversion. */
80 typedef struct conversion conversion;
82 /* The kind of conversion represented by this step. */
84 /* The rank of this conversion. */
86 BOOL_BITFIELD user_conv_p : 1;
87 BOOL_BITFIELD ellipsis_p : 1;
88 BOOL_BITFIELD this_p : 1;
89 BOOL_BITFIELD bad_p : 1;
90 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
91 temporary should be created to hold the result of the
93 BOOL_BITFIELD need_temporary_p : 1;
94 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
95 from a pointer-to-derived to pointer-to-base is being performed. */
96 BOOL_BITFIELD base_p : 1;
97 /* If KIND is ck_ref_bind, true when either an lvalue reference is
98 being bound to an lvalue expression or an rvalue reference is
99 being bound to an rvalue expression. */
100 BOOL_BITFIELD rvaluedness_matches_p: 1;
101 BOOL_BITFIELD check_narrowing: 1;
102 /* The type of the expression resulting from the conversion. */
105 /* The next conversion in the chain. Since the conversions are
106 arranged from outermost to innermost, the NEXT conversion will
107 actually be performed before this conversion. This variant is
108 used only when KIND is neither ck_identity nor ck_ambig. */
110 /* The expression at the beginning of the conversion chain. This
111 variant is used only if KIND is ck_identity or ck_ambig. */
113 /* The array of conversions for an initializer_list. */
116 /* The function candidate corresponding to this conversion
117 sequence. This field is only used if KIND is ck_user. */
118 struct z_candidate *cand;
121 #define CONVERSION_RANK(NODE) \
122 ((NODE)->bad_p ? cr_bad \
123 : (NODE)->ellipsis_p ? cr_ellipsis \
124 : (NODE)->user_conv_p ? cr_user \
127 static struct obstack conversion_obstack;
128 static bool conversion_obstack_initialized;
130 static struct z_candidate * tourney (struct z_candidate *);
131 static int equal_functions (tree, tree);
132 static int joust (struct z_candidate *, struct z_candidate *, bool);
133 static int compare_ics (conversion *, conversion *);
134 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
135 static tree build_java_interface_fn_ref (tree, tree);
136 #define convert_like(CONV, EXPR, COMPLAIN) \
137 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
138 /*issue_conversion_warnings=*/true, \
139 /*c_cast_p=*/false, (COMPLAIN))
140 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
141 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
142 /*issue_conversion_warnings=*/true, \
143 /*c_cast_p=*/false, (COMPLAIN))
144 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
145 bool, tsubst_flags_t);
146 static void op_error (enum tree_code, enum tree_code, tree, tree,
148 static tree resolve_args (tree);
149 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
150 static void print_z_candidate (const char *, struct z_candidate *);
151 static void print_z_candidates (struct z_candidate *);
152 static tree build_this (tree);
153 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
154 static bool any_strictly_viable (struct z_candidate *);
155 static struct z_candidate *add_template_candidate
156 (struct z_candidate **, tree, tree, tree, tree, tree,
157 tree, tree, int, unification_kind_t);
158 static struct z_candidate *add_template_candidate_real
159 (struct z_candidate **, tree, tree, tree, tree, tree,
160 tree, tree, int, tree, unification_kind_t);
161 static struct z_candidate *add_template_conv_candidate
162 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
163 static void add_builtin_candidates
164 (struct z_candidate **, enum tree_code, enum tree_code,
166 static void add_builtin_candidate
167 (struct z_candidate **, enum tree_code, enum tree_code,
168 tree, tree, tree, tree *, tree *, int);
169 static bool is_complete (tree);
170 static void build_builtin_candidate
171 (struct z_candidate **, tree, tree, tree, tree *, tree *,
173 static struct z_candidate *add_conv_candidate
174 (struct z_candidate **, tree, tree, tree, tree, tree);
175 static struct z_candidate *add_function_candidate
176 (struct z_candidate **, tree, tree, tree, tree, tree, int);
177 static conversion *implicit_conversion (tree, tree, tree, bool, int);
178 static conversion *standard_conversion (tree, tree, tree, bool, int);
179 static conversion *reference_binding (tree, tree, tree, bool, int);
180 static conversion *build_conv (conversion_kind, tree, conversion *);
181 static conversion *build_list_conv (tree, tree, int);
182 static bool is_subseq (conversion *, conversion *);
183 static conversion *maybe_handle_ref_bind (conversion **);
184 static void maybe_handle_implicit_object (conversion **);
185 static struct z_candidate *add_candidate
186 (struct z_candidate **, tree, tree, size_t,
187 conversion **, tree, tree, int);
188 static tree source_type (conversion *);
189 static void add_warning (struct z_candidate *, struct z_candidate *);
190 static bool reference_related_p (tree, tree);
191 static bool reference_compatible_p (tree, tree);
192 static conversion *convert_class_to_reference (tree, tree, tree);
193 static conversion *direct_reference_binding (tree, conversion *);
194 static bool promoted_arithmetic_type_p (tree);
195 static conversion *conditional_conversion (tree, tree);
196 static char *name_as_c_string (tree, tree, bool *);
197 static tree call_builtin_trap (void);
198 static tree prep_operand (tree);
199 static void add_candidates (tree, tree, tree, bool, tree, tree,
200 int, struct z_candidate **);
201 static conversion *merge_conversion_sequences (conversion *, conversion *);
202 static bool magic_varargs_p (tree);
203 static tree build_temp (tree, tree, int, diagnostic_t *);
205 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
206 NAME can take many forms... */
209 check_dtor_name (tree basetype, tree name)
211 /* Just accept something we've already complained about. */
212 if (name == error_mark_node)
215 if (TREE_CODE (name) == TYPE_DECL)
216 name = TREE_TYPE (name);
217 else if (TYPE_P (name))
219 else if (TREE_CODE (name) == IDENTIFIER_NODE)
221 if ((MAYBE_CLASS_TYPE_P (basetype)
222 && name == constructor_name (basetype))
223 || (TREE_CODE (basetype) == ENUMERAL_TYPE
224 && name == TYPE_IDENTIFIER (basetype)))
227 name = get_type_value (name);
233 template <class T> struct S { ~S(); };
237 NAME will be a class template. */
238 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
242 if (!name || name == error_mark_node)
244 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
247 /* We want the address of a function or method. We avoid creating a
248 pointer-to-member function. */
251 build_addr_func (tree function)
253 tree type = TREE_TYPE (function);
255 /* We have to do these by hand to avoid real pointer to member
257 if (TREE_CODE (type) == METHOD_TYPE)
259 if (TREE_CODE (function) == OFFSET_REF)
261 tree object = build_address (TREE_OPERAND (function, 0));
262 return get_member_function_from_ptrfunc (&object,
263 TREE_OPERAND (function, 1));
265 function = build_address (function);
268 function = decay_conversion (function);
273 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
274 POINTER_TYPE to those. Note, pointer to member function types
275 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
276 two variants. build_call_a is the primitive taking an array of
277 arguments, while build_call_n is a wrapper that handles varargs. */
280 build_call_n (tree function, int n, ...)
283 return build_call_a (function, 0, NULL);
286 tree *argarray = (tree *) alloca (n * sizeof (tree));
291 for (i = 0; i < n; i++)
292 argarray[i] = va_arg (ap, tree);
294 return build_call_a (function, n, argarray);
299 build_call_a (tree function, int n, tree *argarray)
301 int is_constructor = 0;
308 function = build_addr_func (function);
310 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
311 fntype = TREE_TYPE (TREE_TYPE (function));
312 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
313 || TREE_CODE (fntype) == METHOD_TYPE);
314 result_type = TREE_TYPE (fntype);
316 if (TREE_CODE (function) == ADDR_EXPR
317 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
319 decl = TREE_OPERAND (function, 0);
320 if (!TREE_USED (decl))
322 /* We invoke build_call directly for several library
323 functions. These may have been declared normally if
324 we're building libgcc, so we can't just check
326 gcc_assert (DECL_ARTIFICIAL (decl)
327 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
335 /* We check both the decl and the type; a function may be known not to
336 throw without being declared throw(). */
337 nothrow = ((decl && TREE_NOTHROW (decl))
338 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
340 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
341 current_function_returns_abnormally = 1;
343 if (decl && TREE_DEPRECATED (decl))
344 warn_deprecated_use (decl);
345 require_complete_eh_spec_types (fntype, decl);
347 if (decl && DECL_CONSTRUCTOR_P (decl))
350 /* Don't pass empty class objects by value. This is useful
351 for tags in STL, which are used to control overload resolution.
352 We don't need to handle other cases of copying empty classes. */
353 if (! decl || ! DECL_BUILT_IN (decl))
354 for (i = 0; i < n; i++)
355 if (is_empty_class (TREE_TYPE (argarray[i]))
356 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
358 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
359 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
363 function = build_call_array (result_type, function, n, argarray);
364 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
365 TREE_NOTHROW (function) = nothrow;
370 /* Build something of the form ptr->method (args)
371 or object.method (args). This can also build
372 calls to constructors, and find friends.
374 Member functions always take their class variable
377 INSTANCE is a class instance.
379 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
381 PARMS help to figure out what that NAME really refers to.
383 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
384 down to the real instance type to use for access checking. We need this
385 information to get protected accesses correct.
387 FLAGS is the logical disjunction of zero or more LOOKUP_
388 flags. See cp-tree.h for more info.
390 If this is all OK, calls build_function_call with the resolved
393 This function must also handle being called to perform
394 initialization, promotion/coercion of arguments, and
395 instantiation of default parameters.
397 Note that NAME may refer to an instance variable name. If
398 `operator()()' is defined for the type of that field, then we return
401 /* New overloading code. */
403 typedef struct z_candidate z_candidate;
405 typedef struct candidate_warning candidate_warning;
406 struct candidate_warning {
408 candidate_warning *next;
412 /* The FUNCTION_DECL that will be called if this candidate is
413 selected by overload resolution. */
415 /* The arguments to use when calling this function. */
417 /* The implicit conversion sequences for each of the arguments to
420 /* The number of implicit conversion sequences. */
422 /* If FN is a user-defined conversion, the standard conversion
423 sequence from the type returned by FN to the desired destination
425 conversion *second_conv;
427 /* If FN is a member function, the binfo indicating the path used to
428 qualify the name of FN at the call site. This path is used to
429 determine whether or not FN is accessible if it is selected by
430 overload resolution. The DECL_CONTEXT of FN will always be a
431 (possibly improper) base of this binfo. */
433 /* If FN is a non-static member function, the binfo indicating the
434 subobject to which the `this' pointer should be converted if FN
435 is selected by overload resolution. The type pointed to the by
436 the `this' pointer must correspond to the most derived class
437 indicated by the CONVERSION_PATH. */
438 tree conversion_path;
440 candidate_warning *warnings;
444 /* Returns true iff T is a null pointer constant in the sense of
448 null_ptr_cst_p (tree t)
452 A null pointer constant is an integral constant expression
453 (_expr.const_) rvalue of integer type that evaluates to zero. */
454 t = integral_constant_value (t);
457 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
460 if (!TREE_OVERFLOW (t))
466 /* Returns nonzero if PARMLIST consists of only default parms and/or
470 sufficient_parms_p (const_tree parmlist)
472 for (; parmlist && parmlist != void_list_node;
473 parmlist = TREE_CHAIN (parmlist))
474 if (!TREE_PURPOSE (parmlist))
479 /* Allocate N bytes of memory from the conversion obstack. The memory
480 is zeroed before being returned. */
483 conversion_obstack_alloc (size_t n)
486 if (!conversion_obstack_initialized)
488 gcc_obstack_init (&conversion_obstack);
489 conversion_obstack_initialized = true;
491 p = obstack_alloc (&conversion_obstack, n);
496 /* Dynamically allocate a conversion. */
499 alloc_conversion (conversion_kind kind)
502 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
507 #ifdef ENABLE_CHECKING
509 /* Make sure that all memory on the conversion obstack has been
513 validate_conversion_obstack (void)
515 if (conversion_obstack_initialized)
516 gcc_assert ((obstack_next_free (&conversion_obstack)
517 == obstack_base (&conversion_obstack)));
520 #endif /* ENABLE_CHECKING */
522 /* Dynamically allocate an array of N conversions. */
525 alloc_conversions (size_t n)
527 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
531 build_conv (conversion_kind code, tree type, conversion *from)
534 conversion_rank rank = CONVERSION_RANK (from);
536 /* Note that the caller is responsible for filling in t->cand for
537 user-defined conversions. */
538 t = alloc_conversion (code);
561 t->user_conv_p = (code == ck_user || from->user_conv_p);
562 t->bad_p = from->bad_p;
567 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
568 specialization of std::initializer_list<T>, if such a conversion is
572 build_list_conv (tree type, tree ctor, int flags)
574 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
575 unsigned len = CONSTRUCTOR_NELTS (ctor);
576 conversion **subconvs = alloc_conversions (len);
581 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
584 = implicit_conversion (elttype, TREE_TYPE (val), val,
592 t = alloc_conversion (ck_list);
594 t->u.list = subconvs;
597 for (i = 0; i < len; ++i)
599 conversion *sub = subconvs[i];
600 if (sub->rank > t->rank)
602 if (sub->user_conv_p)
603 t->user_conv_p = true;
611 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
612 aggregate class, if such a conversion is possible. */
615 build_aggr_conv (tree type, tree ctor, int flags)
617 unsigned HOST_WIDE_INT i = 0;
619 tree field = TYPE_FIELDS (type);
621 for (; field; field = TREE_CHAIN (field), ++i)
623 if (TREE_CODE (field) != FIELD_DECL)
625 if (i < CONSTRUCTOR_NELTS (ctor))
627 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
628 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
632 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
636 c = alloc_conversion (ck_aggr);
639 c->user_conv_p = true;
644 /* Build a representation of the identity conversion from EXPR to
645 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
648 build_identity_conv (tree type, tree expr)
652 c = alloc_conversion (ck_identity);
659 /* Converting from EXPR to TYPE was ambiguous in the sense that there
660 were multiple user-defined conversions to accomplish the job.
661 Build a conversion that indicates that ambiguity. */
664 build_ambiguous_conv (tree type, tree expr)
668 c = alloc_conversion (ck_ambig);
676 strip_top_quals (tree t)
678 if (TREE_CODE (t) == ARRAY_TYPE)
680 return cp_build_qualified_type (t, 0);
683 /* Returns the standard conversion path (see [conv]) from type FROM to type
684 TO, if any. For proper handling of null pointer constants, you must
685 also pass the expression EXPR to convert from. If C_CAST_P is true,
686 this conversion is coming from a C-style cast. */
689 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
692 enum tree_code fcode, tcode;
694 bool fromref = false;
696 to = non_reference (to);
697 if (TREE_CODE (from) == REFERENCE_TYPE)
700 from = TREE_TYPE (from);
702 to = strip_top_quals (to);
703 from = strip_top_quals (from);
705 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
706 && expr && type_unknown_p (expr))
708 tsubst_flags_t tflags = tf_conv;
709 if (!(flags & LOOKUP_PROTECT))
710 tflags |= tf_no_access_control;
711 expr = instantiate_type (to, expr, tflags);
712 if (expr == error_mark_node)
714 from = TREE_TYPE (expr);
717 fcode = TREE_CODE (from);
718 tcode = TREE_CODE (to);
720 conv = build_identity_conv (from, expr);
721 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
723 from = type_decays_to (from);
724 fcode = TREE_CODE (from);
725 conv = build_conv (ck_lvalue, from, conv);
727 else if (fromref || (expr && lvalue_p (expr)))
732 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
735 from = strip_top_quals (bitfield_type);
736 fcode = TREE_CODE (from);
739 conv = build_conv (ck_rvalue, from, conv);
742 /* Allow conversion between `__complex__' data types. */
743 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
745 /* The standard conversion sequence to convert FROM to TO is
746 the standard conversion sequence to perform componentwise
748 conversion *part_conv = standard_conversion
749 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
753 conv = build_conv (part_conv->kind, to, conv);
754 conv->rank = part_conv->rank;
762 if (same_type_p (from, to))
765 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
766 && expr && null_ptr_cst_p (expr))
767 conv = build_conv (ck_std, to, conv);
768 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
769 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
771 /* For backwards brain damage compatibility, allow interconversion of
772 pointers and integers with a pedwarn. */
773 conv = build_conv (ck_std, to, conv);
776 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
778 /* For backwards brain damage compatibility, allow interconversion of
779 enums and integers with a pedwarn. */
780 conv = build_conv (ck_std, to, conv);
783 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
784 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
789 if (tcode == POINTER_TYPE
790 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
793 else if (VOID_TYPE_P (TREE_TYPE (to))
794 && !TYPE_PTRMEM_P (from)
795 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
797 from = build_pointer_type
798 (cp_build_qualified_type (void_type_node,
799 cp_type_quals (TREE_TYPE (from))));
800 conv = build_conv (ck_ptr, from, conv);
802 else if (TYPE_PTRMEM_P (from))
804 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
805 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
807 if (DERIVED_FROM_P (fbase, tbase)
808 && (same_type_ignoring_top_level_qualifiers_p
809 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
810 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
812 from = build_ptrmem_type (tbase,
813 TYPE_PTRMEM_POINTED_TO_TYPE (from));
814 conv = build_conv (ck_pmem, from, conv);
816 else if (!same_type_p (fbase, tbase))
819 else if (CLASS_TYPE_P (TREE_TYPE (from))
820 && CLASS_TYPE_P (TREE_TYPE (to))
823 An rvalue of type "pointer to cv D," where D is a
824 class type, can be converted to an rvalue of type
825 "pointer to cv B," where B is a base class (clause
826 _class.derived_) of D. If B is an inaccessible
827 (clause _class.access_) or ambiguous
828 (_class.member.lookup_) base class of D, a program
829 that necessitates this conversion is ill-formed.
830 Therefore, we use DERIVED_FROM_P, and do not check
831 access or uniqueness. */
832 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
835 cp_build_qualified_type (TREE_TYPE (to),
836 cp_type_quals (TREE_TYPE (from)));
837 from = build_pointer_type (from);
838 conv = build_conv (ck_ptr, from, conv);
842 if (tcode == POINTER_TYPE)
844 to_pointee = TREE_TYPE (to);
845 from_pointee = TREE_TYPE (from);
849 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
850 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
853 if (same_type_p (from, to))
855 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
856 /* In a C-style cast, we ignore CV-qualification because we
857 are allowed to perform a static_cast followed by a
859 conv = build_conv (ck_qual, to, conv);
860 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
861 conv = build_conv (ck_qual, to, conv);
862 else if (expr && string_conv_p (to, expr, 0))
863 /* converting from string constant to char *. */
864 conv = build_conv (ck_qual, to, conv);
865 else if (ptr_reasonably_similar (to_pointee, from_pointee))
867 conv = build_conv (ck_ptr, to, conv);
875 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
877 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
878 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
879 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
880 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
882 if (!DERIVED_FROM_P (fbase, tbase)
883 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
884 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
885 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
886 || cp_type_quals (fbase) != cp_type_quals (tbase))
889 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
890 from = build_ptrmemfunc_type (build_pointer_type (from));
891 conv = build_conv (ck_pmem, from, conv);
894 else if (tcode == BOOLEAN_TYPE)
898 An rvalue of arithmetic, unscoped enumeration, pointer, or
899 pointer to member type can be converted to an rvalue of type
901 if (ARITHMETIC_TYPE_P (from)
902 || UNSCOPED_ENUM_P (from)
903 || fcode == POINTER_TYPE
904 || TYPE_PTR_TO_MEMBER_P (from))
906 conv = build_conv (ck_std, to, conv);
907 if (fcode == POINTER_TYPE
908 || TYPE_PTRMEM_P (from)
909 || (TYPE_PTRMEMFUNC_P (from)
910 && conv->rank < cr_pbool))
911 conv->rank = cr_pbool;
917 /* We don't check for ENUMERAL_TYPE here because there are no standard
918 conversions to enum type. */
919 /* As an extension, allow conversion to complex type. */
920 else if (ARITHMETIC_TYPE_P (to))
922 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
923 || SCOPED_ENUM_P (from))
925 conv = build_conv (ck_std, to, conv);
927 /* Give this a better rank if it's a promotion. */
928 if (same_type_p (to, type_promotes_to (from))
929 && conv->u.next->rank <= cr_promotion)
930 conv->rank = cr_promotion;
932 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
933 && vector_types_convertible_p (from, to, false))
934 return build_conv (ck_std, to, conv);
935 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
936 && is_properly_derived_from (from, to))
938 if (conv->kind == ck_rvalue)
940 conv = build_conv (ck_base, to, conv);
941 /* The derived-to-base conversion indicates the initialization
942 of a parameter with base type from an object of a derived
943 type. A temporary object is created to hold the result of
944 the conversion unless we're binding directly to a reference. */
945 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
950 if (flags & LOOKUP_NO_NARROWING)
951 conv->check_narrowing = true;
956 /* Returns nonzero if T1 is reference-related to T2. */
959 reference_related_p (tree t1, tree t2)
961 t1 = TYPE_MAIN_VARIANT (t1);
962 t2 = TYPE_MAIN_VARIANT (t2);
966 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
967 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
969 return (same_type_p (t1, t2)
970 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
971 && DERIVED_FROM_P (t1, t2)));
974 /* Returns nonzero if T1 is reference-compatible with T2. */
977 reference_compatible_p (tree t1, tree t2)
981 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
982 reference-related to T2 and cv1 is the same cv-qualification as,
983 or greater cv-qualification than, cv2. */
984 return (reference_related_p (t1, t2)
985 && at_least_as_qualified_p (t1, t2));
988 /* Determine whether or not the EXPR (of class type S) can be
989 converted to T as in [over.match.ref]. */
992 convert_class_to_reference (tree reference_type, tree s, tree expr)
998 struct z_candidate *candidates;
999 struct z_candidate *cand;
1002 conversions = lookup_conversions (s);
1008 Assuming that "cv1 T" is the underlying type of the reference
1009 being initialized, and "cv S" is the type of the initializer
1010 expression, with S a class type, the candidate functions are
1011 selected as follows:
1013 --The conversion functions of S and its base classes are
1014 considered. Those that are not hidden within S and yield type
1015 "reference to cv2 T2", where "cv1 T" is reference-compatible
1016 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1018 The argument list has one argument, which is the initializer
1023 /* Conceptually, we should take the address of EXPR and put it in
1024 the argument list. Unfortunately, however, that can result in
1025 error messages, which we should not issue now because we are just
1026 trying to find a conversion operator. Therefore, we use NULL,
1027 cast to the appropriate type. */
1028 arglist = build_int_cst (build_pointer_type (s), 0);
1029 arglist = build_tree_list (NULL_TREE, arglist);
1031 t = TREE_TYPE (reference_type);
1035 tree fns = TREE_VALUE (conversions);
1037 for (; fns; fns = OVL_NEXT (fns))
1039 tree f = OVL_CURRENT (fns);
1040 tree t2 = TREE_TYPE (TREE_TYPE (f));
1044 /* If this is a template function, try to get an exact
1046 if (TREE_CODE (f) == TEMPLATE_DECL)
1048 cand = add_template_candidate (&candidates,
1054 TREE_PURPOSE (conversions),
1060 /* Now, see if the conversion function really returns
1061 an lvalue of the appropriate type. From the
1062 point of view of unification, simply returning an
1063 rvalue of the right type is good enough. */
1065 t2 = TREE_TYPE (TREE_TYPE (f));
1066 if (TREE_CODE (t2) != REFERENCE_TYPE
1067 || !reference_compatible_p (t, TREE_TYPE (t2)))
1069 candidates = candidates->next;
1074 else if (TREE_CODE (t2) == REFERENCE_TYPE
1075 && reference_compatible_p (t, TREE_TYPE (t2)))
1076 cand = add_function_candidate (&candidates, f, s, arglist,
1078 TREE_PURPOSE (conversions),
1083 conversion *identity_conv;
1084 /* Build a standard conversion sequence indicating the
1085 binding from the reference type returned by the
1086 function to the desired REFERENCE_TYPE. */
1088 = build_identity_conv (TREE_TYPE (TREE_TYPE
1089 (TREE_TYPE (cand->fn))),
1092 = (direct_reference_binding
1093 (reference_type, identity_conv));
1094 cand->second_conv->rvaluedness_matches_p
1095 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1096 == TYPE_REF_IS_RVALUE (reference_type);
1097 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1100 conversions = TREE_CHAIN (conversions);
1103 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1104 /* If none of the conversion functions worked out, let our caller
1109 cand = tourney (candidates);
1113 /* Now that we know that this is the function we're going to use fix
1114 the dummy first argument. */
1115 cand->args = tree_cons (NULL_TREE,
1117 TREE_CHAIN (cand->args));
1119 /* Build a user-defined conversion sequence representing the
1121 conv = build_conv (ck_user,
1122 TREE_TYPE (TREE_TYPE (cand->fn)),
1123 build_identity_conv (TREE_TYPE (expr), expr));
1126 /* Merge it with the standard conversion sequence from the
1127 conversion function's return type to the desired type. */
1128 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1130 if (cand->viable == -1)
1133 return cand->second_conv;
1136 /* A reference of the indicated TYPE is being bound directly to the
1137 expression represented by the implicit conversion sequence CONV.
1138 Return a conversion sequence for this binding. */
1141 direct_reference_binding (tree type, conversion *conv)
1145 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1146 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1148 t = TREE_TYPE (type);
1152 When a parameter of reference type binds directly
1153 (_dcl.init.ref_) to an argument expression, the implicit
1154 conversion sequence is the identity conversion, unless the
1155 argument expression has a type that is a derived class of the
1156 parameter type, in which case the implicit conversion sequence is
1157 a derived-to-base Conversion.
1159 If the parameter binds directly to the result of applying a
1160 conversion function to the argument expression, the implicit
1161 conversion sequence is a user-defined conversion sequence
1162 (_over.ics.user_), with the second standard conversion sequence
1163 either an identity conversion or, if the conversion function
1164 returns an entity of a type that is a derived class of the
1165 parameter type, a derived-to-base conversion. */
1166 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1168 /* Represent the derived-to-base conversion. */
1169 conv = build_conv (ck_base, t, conv);
1170 /* We will actually be binding to the base-class subobject in
1171 the derived class, so we mark this conversion appropriately.
1172 That way, convert_like knows not to generate a temporary. */
1173 conv->need_temporary_p = false;
1175 return build_conv (ck_ref_bind, type, conv);
1178 /* Returns the conversion path from type FROM to reference type TO for
1179 purposes of reference binding. For lvalue binding, either pass a
1180 reference type to FROM or an lvalue expression to EXPR. If the
1181 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1182 the conversion returned. If C_CAST_P is true, this
1183 conversion is coming from a C-style cast. */
1186 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1188 conversion *conv = NULL;
1189 tree to = TREE_TYPE (rto);
1194 cp_lvalue_kind lvalue_p = clk_none;
1196 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1198 expr = instantiate_type (to, expr, tf_none);
1199 if (expr == error_mark_node)
1201 from = TREE_TYPE (expr);
1204 if (TREE_CODE (from) == REFERENCE_TYPE)
1206 /* Anything with reference type is an lvalue. */
1207 lvalue_p = clk_ordinary;
1208 from = TREE_TYPE (from);
1211 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1213 maybe_warn_cpp0x ("extended initializer lists");
1214 conv = implicit_conversion (to, from, expr, c_cast_p,
1216 if (!CLASS_TYPE_P (to)
1217 && CONSTRUCTOR_NELTS (expr) == 1)
1219 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1220 if (error_operand_p (expr))
1222 from = TREE_TYPE (expr);
1226 if (lvalue_p == clk_none && expr)
1227 lvalue_p = real_lvalue_p (expr);
1230 if ((lvalue_p & clk_bitfield) != 0)
1231 tfrom = unlowered_expr_type (expr);
1233 /* Figure out whether or not the types are reference-related and
1234 reference compatible. We have do do this after stripping
1235 references from FROM. */
1236 related_p = reference_related_p (to, tfrom);
1237 /* If this is a C cast, first convert to an appropriately qualified
1238 type, so that we can later do a const_cast to the desired type. */
1239 if (related_p && c_cast_p
1240 && !at_least_as_qualified_p (to, tfrom))
1241 to = build_qualified_type (to, cp_type_quals (tfrom));
1242 compatible_p = reference_compatible_p (to, tfrom);
1244 /* Directly bind reference when target expression's type is compatible with
1245 the reference and expression is an lvalue. In DR391, the wording in
1246 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1247 const and rvalue references to rvalues of compatible class type. */
1250 || (!(flags & LOOKUP_NO_TEMP_BIND)
1251 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1252 && CLASS_TYPE_P (from))))
1256 If the initializer expression
1258 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1259 is reference-compatible with "cv2 T2,"
1261 the reference is bound directly to the initializer expression
1265 If the initializer expression is an rvalue, with T2 a class type,
1266 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1267 is bound to the object represented by the rvalue or to a sub-object
1268 within that object. */
1270 conv = build_identity_conv (tfrom, expr);
1271 conv = direct_reference_binding (rto, conv);
1273 if (flags & LOOKUP_PREFER_RVALUE)
1274 /* The top-level caller requested that we pretend that the lvalue
1275 be treated as an rvalue. */
1276 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1278 conv->rvaluedness_matches_p
1279 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1281 if ((lvalue_p & clk_bitfield) != 0
1282 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1283 /* For the purposes of overload resolution, we ignore the fact
1284 this expression is a bitfield or packed field. (In particular,
1285 [over.ics.ref] says specifically that a function with a
1286 non-const reference parameter is viable even if the
1287 argument is a bitfield.)
1289 However, when we actually call the function we must create
1290 a temporary to which to bind the reference. If the
1291 reference is volatile, or isn't const, then we cannot make
1292 a temporary, so we just issue an error when the conversion
1294 conv->need_temporary_p = true;
1298 /* [class.conv.fct] A conversion function is never used to convert a
1299 (possibly cv-qualified) object to the (possibly cv-qualified) same
1300 object type (or a reference to it), to a (possibly cv-qualified) base
1301 class of that type (or a reference to it).... */
1302 else if (CLASS_TYPE_P (from) && !related_p
1303 && !(flags & LOOKUP_NO_CONVERSION))
1307 If the initializer expression
1309 -- has a class type (i.e., T2 is a class type) can be
1310 implicitly converted to an lvalue of type "cv3 T3," where
1311 "cv1 T1" is reference-compatible with "cv3 T3". (this
1312 conversion is selected by enumerating the applicable
1313 conversion functions (_over.match.ref_) and choosing the
1314 best one through overload resolution. (_over.match_).
1316 the reference is bound to the lvalue result of the conversion
1317 in the second case. */
1318 conv = convert_class_to_reference (rto, from, expr);
1323 /* From this point on, we conceptually need temporaries, even if we
1324 elide them. Only the cases above are "direct bindings". */
1325 if (flags & LOOKUP_NO_TEMP_BIND)
1330 When a parameter of reference type is not bound directly to an
1331 argument expression, the conversion sequence is the one required
1332 to convert the argument expression to the underlying type of the
1333 reference according to _over.best.ics_. Conceptually, this
1334 conversion sequence corresponds to copy-initializing a temporary
1335 of the underlying type with the argument expression. Any
1336 difference in top-level cv-qualification is subsumed by the
1337 initialization itself and does not constitute a conversion. */
1341 Otherwise, the reference shall be to a non-volatile const type.
1343 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1344 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1349 Otherwise, a temporary of type "cv1 T1" is created and
1350 initialized from the initializer expression using the rules for a
1351 non-reference copy initialization. If T1 is reference-related to
1352 T2, cv1 must be the same cv-qualification as, or greater
1353 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1354 if (related_p && !at_least_as_qualified_p (to, from))
1357 /* We're generating a temporary now, but don't bind any more in the
1358 conversion (specifically, don't slice the temporary returned by a
1359 conversion operator). */
1360 flags |= LOOKUP_NO_TEMP_BIND;
1363 conv = implicit_conversion (to, from, expr, c_cast_p,
1368 conv = build_conv (ck_ref_bind, rto, conv);
1369 /* This reference binding, unlike those above, requires the
1370 creation of a temporary. */
1371 conv->need_temporary_p = true;
1372 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1377 /* Returns the implicit conversion sequence (see [over.ics]) from type
1378 FROM to type TO. The optional expression EXPR may affect the
1379 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1380 true, this conversion is coming from a C-style cast. */
1383 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1388 if (from == error_mark_node || to == error_mark_node
1389 || expr == error_mark_node)
1392 if (TREE_CODE (to) == REFERENCE_TYPE)
1393 conv = reference_binding (to, from, expr, c_cast_p, flags);
1395 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1400 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1402 if (is_std_init_list (to))
1403 return build_list_conv (to, expr, flags);
1405 /* Allow conversion from an initializer-list with one element to a
1407 if (SCALAR_TYPE_P (to))
1409 int nelts = CONSTRUCTOR_NELTS (expr);
1413 elt = integer_zero_node;
1414 else if (nelts == 1)
1415 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1417 elt = error_mark_node;
1419 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1423 conv->check_narrowing = true;
1424 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1425 /* Too many levels of braces, i.e. '{{1}}'. */
1432 if (expr != NULL_TREE
1433 && (MAYBE_CLASS_TYPE_P (from)
1434 || MAYBE_CLASS_TYPE_P (to))
1435 && (flags & LOOKUP_NO_CONVERSION) == 0)
1437 struct z_candidate *cand;
1438 int convflags = ((flags & LOOKUP_NO_TEMP_BIND)
1439 |LOOKUP_ONLYCONVERTING);
1441 if (CLASS_TYPE_P (to)
1442 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1443 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1444 return build_aggr_conv (to, expr, flags);
1446 cand = build_user_type_conversion_1 (to, expr, convflags);
1448 conv = cand->second_conv;
1450 /* We used to try to bind a reference to a temporary here, but that
1451 is now handled after the recursive call to this function at the end
1452 of reference_binding. */
1459 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1462 static struct z_candidate *
1463 add_candidate (struct z_candidate **candidates,
1465 size_t num_convs, conversion **convs,
1466 tree access_path, tree conversion_path,
1469 struct z_candidate *cand = (struct z_candidate *)
1470 conversion_obstack_alloc (sizeof (struct z_candidate));
1474 cand->convs = convs;
1475 cand->num_convs = num_convs;
1476 cand->access_path = access_path;
1477 cand->conversion_path = conversion_path;
1478 cand->viable = viable;
1479 cand->next = *candidates;
1485 /* Create an overload candidate for the function or method FN called with
1486 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1487 to implicit_conversion.
1489 CTYPE, if non-NULL, is the type we want to pretend this function
1490 comes from for purposes of overload resolution. */
1492 static struct z_candidate *
1493 add_function_candidate (struct z_candidate **candidates,
1494 tree fn, tree ctype, tree arglist,
1495 tree access_path, tree conversion_path,
1498 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1501 tree parmnode, argnode;
1505 /* At this point we should not see any functions which haven't been
1506 explicitly declared, except for friend functions which will have
1507 been found using argument dependent lookup. */
1508 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1510 /* The `this', `in_chrg' and VTT arguments to constructors are not
1511 considered in overload resolution. */
1512 if (DECL_CONSTRUCTOR_P (fn))
1514 parmlist = skip_artificial_parms_for (fn, parmlist);
1515 orig_arglist = arglist;
1516 arglist = skip_artificial_parms_for (fn, arglist);
1519 orig_arglist = arglist;
1521 len = list_length (arglist);
1522 convs = alloc_conversions (len);
1524 /* 13.3.2 - Viable functions [over.match.viable]
1525 First, to be a viable function, a candidate function shall have enough
1526 parameters to agree in number with the arguments in the list.
1528 We need to check this first; otherwise, checking the ICSes might cause
1529 us to produce an ill-formed template instantiation. */
1531 parmnode = parmlist;
1532 for (i = 0; i < len; ++i)
1534 if (parmnode == NULL_TREE || parmnode == void_list_node)
1536 parmnode = TREE_CHAIN (parmnode);
1539 if (i < len && parmnode)
1542 /* Make sure there are default args for the rest of the parms. */
1543 else if (!sufficient_parms_p (parmnode))
1549 /* Second, for F to be a viable function, there shall exist for each
1550 argument an implicit conversion sequence that converts that argument
1551 to the corresponding parameter of F. */
1553 parmnode = parmlist;
1556 for (i = 0; i < len; ++i)
1558 tree arg = TREE_VALUE (argnode);
1559 tree argtype = lvalue_type (arg);
1563 if (parmnode == void_list_node)
1566 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1567 && ! DECL_CONSTRUCTOR_P (fn));
1571 tree parmtype = TREE_VALUE (parmnode);
1574 /* The type of the implicit object parameter ('this') for
1575 overload resolution is not always the same as for the
1576 function itself; conversion functions are considered to
1577 be members of the class being converted, and functions
1578 introduced by a using-declaration are considered to be
1579 members of the class that uses them.
1581 Since build_over_call ignores the ICS for the `this'
1582 parameter, we can just change the parm type. */
1583 if (ctype && is_this)
1586 = build_qualified_type (ctype,
1587 TYPE_QUALS (TREE_TYPE (parmtype)));
1588 parmtype = build_pointer_type (parmtype);
1591 if ((flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1592 && ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1593 lflags |= LOOKUP_NO_CONVERSION;
1595 t = implicit_conversion (parmtype, argtype, arg,
1596 /*c_cast_p=*/false, lflags);
1600 t = build_identity_conv (argtype, arg);
1601 t->ellipsis_p = true;
1618 parmnode = TREE_CHAIN (parmnode);
1619 argnode = TREE_CHAIN (argnode);
1623 return add_candidate (candidates, fn, orig_arglist, len, convs,
1624 access_path, conversion_path, viable);
1627 /* Create an overload candidate for the conversion function FN which will
1628 be invoked for expression OBJ, producing a pointer-to-function which
1629 will in turn be called with the argument list ARGLIST, and add it to
1630 CANDIDATES. FLAGS is passed on to implicit_conversion.
1632 Actually, we don't really care about FN; we care about the type it
1633 converts to. There may be multiple conversion functions that will
1634 convert to that type, and we rely on build_user_type_conversion_1 to
1635 choose the best one; so when we create our candidate, we record the type
1636 instead of the function. */
1638 static struct z_candidate *
1639 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1640 tree arglist, tree access_path, tree conversion_path)
1642 tree totype = TREE_TYPE (TREE_TYPE (fn));
1643 int i, len, viable, flags;
1644 tree parmlist, parmnode, argnode;
1647 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1648 parmlist = TREE_TYPE (parmlist);
1649 parmlist = TYPE_ARG_TYPES (parmlist);
1651 len = list_length (arglist) + 1;
1652 convs = alloc_conversions (len);
1653 parmnode = parmlist;
1656 flags = LOOKUP_NORMAL;
1658 /* Don't bother looking up the same type twice. */
1659 if (*candidates && (*candidates)->fn == totype)
1662 for (i = 0; i < len; ++i)
1664 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1665 tree argtype = lvalue_type (arg);
1669 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1671 else if (parmnode == void_list_node)
1674 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1675 /*c_cast_p=*/false, flags);
1678 t = build_identity_conv (argtype, arg);
1679 t->ellipsis_p = true;
1693 parmnode = TREE_CHAIN (parmnode);
1694 argnode = TREE_CHAIN (argnode);
1700 if (!sufficient_parms_p (parmnode))
1703 return add_candidate (candidates, totype, arglist, len, convs,
1704 access_path, conversion_path, viable);
1708 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1709 tree type1, tree type2, tree *args, tree *argtypes,
1721 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1722 convs = alloc_conversions (num_convs);
1724 for (i = 0; i < 2; ++i)
1729 t = implicit_conversion (types[i], argtypes[i], args[i],
1730 /*c_cast_p=*/false, flags);
1734 /* We need something for printing the candidate. */
1735 t = build_identity_conv (types[i], NULL_TREE);
1742 /* For COND_EXPR we rearranged the arguments; undo that now. */
1745 convs[2] = convs[1];
1746 convs[1] = convs[0];
1747 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1748 /*c_cast_p=*/false, flags);
1755 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1757 /*access_path=*/NULL_TREE,
1758 /*conversion_path=*/NULL_TREE,
1763 is_complete (tree t)
1765 return COMPLETE_TYPE_P (complete_type (t));
1768 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1771 promoted_arithmetic_type_p (tree type)
1775 In this section, the term promoted integral type is used to refer
1776 to those integral types which are preserved by integral promotion
1777 (including e.g. int and long but excluding e.g. char).
1778 Similarly, the term promoted arithmetic type refers to promoted
1779 integral types plus floating types. */
1780 return ((INTEGRAL_TYPE_P (type)
1781 && same_type_p (type_promotes_to (type), type))
1782 || TREE_CODE (type) == REAL_TYPE);
1785 /* Create any builtin operator overload candidates for the operator in
1786 question given the converted operand types TYPE1 and TYPE2. The other
1787 args are passed through from add_builtin_candidates to
1788 build_builtin_candidate.
1790 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1791 If CODE is requires candidates operands of the same type of the kind
1792 of which TYPE1 and TYPE2 are, we add both candidates
1793 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1796 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1797 enum tree_code code2, tree fnname, tree type1,
1798 tree type2, tree *args, tree *argtypes, int flags)
1802 case POSTINCREMENT_EXPR:
1803 case POSTDECREMENT_EXPR:
1804 args[1] = integer_zero_node;
1805 type2 = integer_type_node;
1814 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1815 and VQ is either volatile or empty, there exist candidate operator
1816 functions of the form
1817 VQ T& operator++(VQ T&);
1818 T operator++(VQ T&, int);
1819 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1820 type other than bool, and VQ is either volatile or empty, there exist
1821 candidate operator functions of the form
1822 VQ T& operator--(VQ T&);
1823 T operator--(VQ T&, int);
1824 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1825 complete object type, and VQ is either volatile or empty, there exist
1826 candidate operator functions of the form
1827 T*VQ& operator++(T*VQ&);
1828 T*VQ& operator--(T*VQ&);
1829 T* operator++(T*VQ&, int);
1830 T* operator--(T*VQ&, int); */
1832 case POSTDECREMENT_EXPR:
1833 case PREDECREMENT_EXPR:
1834 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1836 case POSTINCREMENT_EXPR:
1837 case PREINCREMENT_EXPR:
1838 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1840 type1 = build_reference_type (type1);
1845 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1846 exist candidate operator functions of the form
1850 8 For every function type T, there exist candidate operator functions of
1852 T& operator*(T*); */
1855 if (TREE_CODE (type1) == POINTER_TYPE
1856 && (TYPE_PTROB_P (type1)
1857 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1861 /* 9 For every type T, there exist candidate operator functions of the form
1864 10For every promoted arithmetic type T, there exist candidate operator
1865 functions of the form
1869 case UNARY_PLUS_EXPR: /* unary + */
1870 if (TREE_CODE (type1) == POINTER_TYPE)
1873 if (ARITHMETIC_TYPE_P (type1))
1877 /* 11For every promoted integral type T, there exist candidate operator
1878 functions of the form
1882 if (INTEGRAL_TYPE_P (type1))
1886 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1887 is the same type as C2 or is a derived class of C2, T is a complete
1888 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1889 there exist candidate operator functions of the form
1890 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1891 where CV12 is the union of CV1 and CV2. */
1894 if (TREE_CODE (type1) == POINTER_TYPE
1895 && TYPE_PTR_TO_MEMBER_P (type2))
1897 tree c1 = TREE_TYPE (type1);
1898 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1900 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1901 && (TYPE_PTRMEMFUNC_P (type2)
1902 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1907 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1908 didate operator functions of the form
1913 bool operator<(L, R);
1914 bool operator>(L, R);
1915 bool operator<=(L, R);
1916 bool operator>=(L, R);
1917 bool operator==(L, R);
1918 bool operator!=(L, R);
1919 where LR is the result of the usual arithmetic conversions between
1922 14For every pair of types T and I, where T is a cv-qualified or cv-
1923 unqualified complete object type and I is a promoted integral type,
1924 there exist candidate operator functions of the form
1925 T* operator+(T*, I);
1926 T& operator[](T*, I);
1927 T* operator-(T*, I);
1928 T* operator+(I, T*);
1929 T& operator[](I, T*);
1931 15For every T, where T is a pointer to complete object type, there exist
1932 candidate operator functions of the form112)
1933 ptrdiff_t operator-(T, T);
1935 16For every pointer or enumeration type T, there exist candidate operator
1936 functions of the form
1937 bool operator<(T, T);
1938 bool operator>(T, T);
1939 bool operator<=(T, T);
1940 bool operator>=(T, T);
1941 bool operator==(T, T);
1942 bool operator!=(T, T);
1944 17For every pointer to member type T, there exist candidate operator
1945 functions of the form
1946 bool operator==(T, T);
1947 bool operator!=(T, T); */
1950 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1952 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1954 type2 = ptrdiff_type_node;
1958 case TRUNC_DIV_EXPR:
1959 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1965 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1966 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1968 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1973 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1985 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1987 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1989 if (TREE_CODE (type1) == ENUMERAL_TYPE
1990 && TREE_CODE (type2) == ENUMERAL_TYPE)
1992 if (TYPE_PTR_P (type1)
1993 && null_ptr_cst_p (args[1])
1994 && !uses_template_parms (type1))
1999 if (null_ptr_cst_p (args[0])
2000 && TYPE_PTR_P (type2)
2001 && !uses_template_parms (type2))
2009 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2012 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
2014 type1 = ptrdiff_type_node;
2017 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
2019 type2 = ptrdiff_type_node;
2024 /* 18For every pair of promoted integral types L and R, there exist candi-
2025 date operator functions of the form
2032 where LR is the result of the usual arithmetic conversions between
2035 case TRUNC_MOD_EXPR:
2041 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2045 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2046 type, VQ is either volatile or empty, and R is a promoted arithmetic
2047 type, there exist candidate operator functions of the form
2048 VQ L& operator=(VQ L&, R);
2049 VQ L& operator*=(VQ L&, R);
2050 VQ L& operator/=(VQ L&, R);
2051 VQ L& operator+=(VQ L&, R);
2052 VQ L& operator-=(VQ L&, R);
2054 20For every pair T, VQ), where T is any type and VQ is either volatile
2055 or empty, there exist candidate operator functions of the form
2056 T*VQ& operator=(T*VQ&, T*);
2058 21For every pair T, VQ), where T is a pointer to member type and VQ is
2059 either volatile or empty, there exist candidate operator functions of
2061 VQ T& operator=(VQ T&, T);
2063 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2064 unqualified complete object type, VQ is either volatile or empty, and
2065 I is a promoted integral type, there exist candidate operator func-
2067 T*VQ& operator+=(T*VQ&, I);
2068 T*VQ& operator-=(T*VQ&, I);
2070 23For every triple L, VQ, R), where L is an integral or enumeration
2071 type, VQ is either volatile or empty, and R is a promoted integral
2072 type, there exist candidate operator functions of the form
2074 VQ L& operator%=(VQ L&, R);
2075 VQ L& operator<<=(VQ L&, R);
2076 VQ L& operator>>=(VQ L&, R);
2077 VQ L& operator&=(VQ L&, R);
2078 VQ L& operator^=(VQ L&, R);
2079 VQ L& operator|=(VQ L&, R); */
2086 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
2088 type2 = ptrdiff_type_node;
2092 case TRUNC_DIV_EXPR:
2093 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2097 case TRUNC_MOD_EXPR:
2103 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2108 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2110 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2111 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2112 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2113 || ((TYPE_PTRMEMFUNC_P (type1)
2114 || TREE_CODE (type1) == POINTER_TYPE)
2115 && null_ptr_cst_p (args[1])))
2125 type1 = build_reference_type (type1);
2131 For every pair of promoted arithmetic types L and R, there
2132 exist candidate operator functions of the form
2134 LR operator?(bool, L, R);
2136 where LR is the result of the usual arithmetic conversions
2137 between types L and R.
2139 For every type T, where T is a pointer or pointer-to-member
2140 type, there exist candidate operator functions of the form T
2141 operator?(bool, T, T); */
2143 if (promoted_arithmetic_type_p (type1)
2144 && promoted_arithmetic_type_p (type2))
2148 /* Otherwise, the types should be pointers. */
2149 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2150 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2153 /* We don't check that the two types are the same; the logic
2154 below will actually create two candidates; one in which both
2155 parameter types are TYPE1, and one in which both parameter
2163 /* If we're dealing with two pointer types or two enumeral types,
2164 we need candidates for both of them. */
2165 if (type2 && !same_type_p (type1, type2)
2166 && TREE_CODE (type1) == TREE_CODE (type2)
2167 && (TREE_CODE (type1) == REFERENCE_TYPE
2168 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2169 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2170 || TYPE_PTRMEMFUNC_P (type1)
2171 || MAYBE_CLASS_TYPE_P (type1)
2172 || TREE_CODE (type1) == ENUMERAL_TYPE))
2174 build_builtin_candidate
2175 (candidates, fnname, type1, type1, args, argtypes, flags);
2176 build_builtin_candidate
2177 (candidates, fnname, type2, type2, args, argtypes, flags);
2181 build_builtin_candidate
2182 (candidates, fnname, type1, type2, args, argtypes, flags);
2186 type_decays_to (tree type)
2188 if (TREE_CODE (type) == ARRAY_TYPE)
2189 return build_pointer_type (TREE_TYPE (type));
2190 if (TREE_CODE (type) == FUNCTION_TYPE)
2191 return build_pointer_type (type);
2195 /* There are three conditions of builtin candidates:
2197 1) bool-taking candidates. These are the same regardless of the input.
2198 2) pointer-pair taking candidates. These are generated for each type
2199 one of the input types converts to.
2200 3) arithmetic candidates. According to the standard, we should generate
2201 all of these, but I'm trying not to...
2203 Here we generate a superset of the possible candidates for this particular
2204 case. That is a subset of the full set the standard defines, plus some
2205 other cases which the standard disallows. add_builtin_candidate will
2206 filter out the invalid set. */
2209 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2210 enum tree_code code2, tree fnname, tree *args,
2215 tree type, argtypes[3];
2216 /* TYPES[i] is the set of possible builtin-operator parameter types
2217 we will consider for the Ith argument. These are represented as
2218 a TREE_LIST; the TREE_VALUE of each node is the potential
2222 for (i = 0; i < 3; ++i)
2225 argtypes[i] = unlowered_expr_type (args[i]);
2227 argtypes[i] = NULL_TREE;
2232 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2233 and VQ is either volatile or empty, there exist candidate operator
2234 functions of the form
2235 VQ T& operator++(VQ T&); */
2237 case POSTINCREMENT_EXPR:
2238 case PREINCREMENT_EXPR:
2239 case POSTDECREMENT_EXPR:
2240 case PREDECREMENT_EXPR:
2245 /* 24There also exist candidate operator functions of the form
2246 bool operator!(bool);
2247 bool operator&&(bool, bool);
2248 bool operator||(bool, bool); */
2250 case TRUTH_NOT_EXPR:
2251 build_builtin_candidate
2252 (candidates, fnname, boolean_type_node,
2253 NULL_TREE, args, argtypes, flags);
2256 case TRUTH_ORIF_EXPR:
2257 case TRUTH_ANDIF_EXPR:
2258 build_builtin_candidate
2259 (candidates, fnname, boolean_type_node,
2260 boolean_type_node, args, argtypes, flags);
2282 types[0] = types[1] = NULL_TREE;
2284 for (i = 0; i < 2; ++i)
2288 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2292 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2295 convs = lookup_conversions (argtypes[i]);
2297 if (code == COND_EXPR)
2299 if (real_lvalue_p (args[i]))
2300 types[i] = tree_cons
2301 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2303 types[i] = tree_cons
2304 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2310 for (; convs; convs = TREE_CHAIN (convs))
2312 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2315 && (TREE_CODE (type) != REFERENCE_TYPE
2316 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2319 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2320 types[i] = tree_cons (NULL_TREE, type, types[i]);
2322 type = non_reference (type);
2323 if (i != 0 || ! ref1)
2325 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2326 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2327 types[i] = tree_cons (NULL_TREE, type, types[i]);
2328 if (INTEGRAL_TYPE_P (type))
2329 type = type_promotes_to (type);
2332 if (! value_member (type, types[i]))
2333 types[i] = tree_cons (NULL_TREE, type, types[i]);
2338 if (code == COND_EXPR && real_lvalue_p (args[i]))
2339 types[i] = tree_cons
2340 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2341 type = non_reference (argtypes[i]);
2342 if (i != 0 || ! ref1)
2344 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2345 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2346 types[i] = tree_cons (NULL_TREE, type, types[i]);
2347 if (INTEGRAL_TYPE_P (type))
2348 type = type_promotes_to (type);
2350 types[i] = tree_cons (NULL_TREE, type, types[i]);
2354 /* Run through the possible parameter types of both arguments,
2355 creating candidates with those parameter types. */
2356 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2359 for (type = types[1]; type; type = TREE_CHAIN (type))
2360 add_builtin_candidate
2361 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2362 TREE_VALUE (type), args, argtypes, flags);
2364 add_builtin_candidate
2365 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2366 NULL_TREE, args, argtypes, flags);
2371 /* If TMPL can be successfully instantiated as indicated by
2372 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2374 TMPL is the template. EXPLICIT_TARGS are any explicit template
2375 arguments. ARGLIST is the arguments provided at the call-site.
2376 The RETURN_TYPE is the desired type for conversion operators. If
2377 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2378 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2379 add_conv_candidate. */
2381 static struct z_candidate*
2382 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2383 tree ctype, tree explicit_targs, tree arglist,
2384 tree return_type, tree access_path,
2385 tree conversion_path, int flags, tree obj,
2386 unification_kind_t strict)
2388 int ntparms = DECL_NTPARMS (tmpl);
2389 tree targs = make_tree_vec (ntparms);
2390 tree args_without_in_chrg = arglist;
2391 struct z_candidate *cand;
2395 /* We don't do deduction on the in-charge parameter, the VTT
2396 parameter or 'this'. */
2397 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2398 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2400 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2401 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2402 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2403 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2405 i = fn_type_unification (tmpl, explicit_targs, targs,
2406 args_without_in_chrg,
2407 return_type, strict, flags);
2412 fn = instantiate_template (tmpl, targs, tf_none);
2413 if (fn == error_mark_node)
2418 A member function template is never instantiated to perform the
2419 copy of a class object to an object of its class type.
2421 It's a little unclear what this means; the standard explicitly
2422 does allow a template to be used to copy a class. For example,
2427 template <class T> A(const T&);
2430 void g () { A a (f ()); }
2432 the member template will be used to make the copy. The section
2433 quoted above appears in the paragraph that forbids constructors
2434 whose only parameter is (a possibly cv-qualified variant of) the
2435 class type, and a logical interpretation is that the intent was
2436 to forbid the instantiation of member templates which would then
2438 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2440 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2441 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2446 if (obj != NULL_TREE)
2447 /* Aha, this is a conversion function. */
2448 cand = add_conv_candidate (candidates, fn, obj, access_path,
2449 conversion_path, arglist);
2451 cand = add_function_candidate (candidates, fn, ctype,
2452 arglist, access_path,
2453 conversion_path, flags);
2454 if (DECL_TI_TEMPLATE (fn) != tmpl)
2455 /* This situation can occur if a member template of a template
2456 class is specialized. Then, instantiate_template might return
2457 an instantiation of the specialization, in which case the
2458 DECL_TI_TEMPLATE field will point at the original
2459 specialization. For example:
2461 template <class T> struct S { template <class U> void f(U);
2462 template <> void f(int) {}; };
2466 Here, TMPL will be template <class U> S<double>::f(U).
2467 And, instantiate template will give us the specialization
2468 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2469 for this will point at template <class T> template <> S<T>::f(int),
2470 so that we can find the definition. For the purposes of
2471 overload resolution, however, we want the original TMPL. */
2472 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2474 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2480 static struct z_candidate *
2481 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2482 tree explicit_targs, tree arglist, tree return_type,
2483 tree access_path, tree conversion_path, int flags,
2484 unification_kind_t strict)
2487 add_template_candidate_real (candidates, tmpl, ctype,
2488 explicit_targs, arglist, return_type,
2489 access_path, conversion_path,
2490 flags, NULL_TREE, strict);
2494 static struct z_candidate *
2495 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2496 tree obj, tree arglist, tree return_type,
2497 tree access_path, tree conversion_path)
2500 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2501 arglist, return_type, access_path,
2502 conversion_path, 0, obj, DEDUCE_CONV);
2505 /* The CANDS are the set of candidates that were considered for
2506 overload resolution. Return the set of viable candidates. If none
2507 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2508 is true if a candidate should be considered viable only if it is
2511 static struct z_candidate*
2512 splice_viable (struct z_candidate *cands,
2516 struct z_candidate *viable;
2517 struct z_candidate **last_viable;
2518 struct z_candidate **cand;
2521 last_viable = &viable;
2522 *any_viable_p = false;
2527 struct z_candidate *c = *cand;
2528 if (strict_p ? c->viable == 1 : c->viable)
2533 last_viable = &c->next;
2534 *any_viable_p = true;
2540 return viable ? viable : cands;
2544 any_strictly_viable (struct z_candidate *cands)
2546 for (; cands; cands = cands->next)
2547 if (cands->viable == 1)
2552 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2553 words, it is about to become the "this" pointer for a member
2554 function call. Take the address of the object. */
2557 build_this (tree obj)
2559 /* In a template, we are only concerned about the type of the
2560 expression, so we can take a shortcut. */
2561 if (processing_template_decl)
2562 return build_address (obj);
2564 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2567 /* Returns true iff functions are equivalent. Equivalent functions are
2568 not '==' only if one is a function-local extern function or if
2569 both are extern "C". */
2572 equal_functions (tree fn1, tree fn2)
2574 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2575 || DECL_EXTERN_C_FUNCTION_P (fn1))
2576 return decls_match (fn1, fn2);
2580 /* Print information about one overload candidate CANDIDATE. MSGSTR
2581 is the text to print before the candidate itself.
2583 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2584 to have been run through gettext by the caller. This wart makes
2585 life simpler in print_z_candidates and for the translators. */
2588 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2590 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2592 if (candidate->num_convs == 3)
2593 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2594 candidate->convs[0]->type,
2595 candidate->convs[1]->type,
2596 candidate->convs[2]->type);
2597 else if (candidate->num_convs == 2)
2598 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2599 candidate->convs[0]->type,
2600 candidate->convs[1]->type);
2602 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2603 candidate->convs[0]->type);
2605 else if (TYPE_P (candidate->fn))
2606 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2607 else if (candidate->viable == -1)
2608 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2610 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2614 print_z_candidates (struct z_candidate *candidates)
2617 struct z_candidate *cand1;
2618 struct z_candidate **cand2;
2620 /* There may be duplicates in the set of candidates. We put off
2621 checking this condition as long as possible, since we have no way
2622 to eliminate duplicates from a set of functions in less than n^2
2623 time. Now we are about to emit an error message, so it is more
2624 permissible to go slowly. */
2625 for (cand1 = candidates; cand1; cand1 = cand1->next)
2627 tree fn = cand1->fn;
2628 /* Skip builtin candidates and conversion functions. */
2629 if (TREE_CODE (fn) != FUNCTION_DECL)
2631 cand2 = &cand1->next;
2634 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2635 && equal_functions (fn, (*cand2)->fn))
2636 *cand2 = (*cand2)->next;
2638 cand2 = &(*cand2)->next;
2645 str = _("candidates are:");
2646 print_z_candidate (str, candidates);
2647 if (candidates->next)
2649 /* Indent successive candidates by the width of the translation
2650 of the above string. */
2651 size_t len = gcc_gettext_width (str) + 1;
2652 char *spaces = (char *) alloca (len);
2653 memset (spaces, ' ', len-1);
2654 spaces[len - 1] = '\0';
2656 candidates = candidates->next;
2659 print_z_candidate (spaces, candidates);
2660 candidates = candidates->next;
2666 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2667 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2668 the result of the conversion function to convert it to the final
2669 desired type. Merge the two sequences into a single sequence,
2670 and return the merged sequence. */
2673 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2677 gcc_assert (user_seq->kind == ck_user);
2679 /* Find the end of the second conversion sequence. */
2681 while ((*t)->kind != ck_identity)
2682 t = &((*t)->u.next);
2684 /* Replace the identity conversion with the user conversion
2688 /* The entire sequence is a user-conversion sequence. */
2689 std_seq->user_conv_p = true;
2694 /* Returns the best overload candidate to perform the requested
2695 conversion. This function is used for three the overloading situations
2696 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2697 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2698 per [dcl.init.ref], so we ignore temporary bindings. */
2700 static struct z_candidate *
2701 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2703 struct z_candidate *candidates, *cand;
2704 tree fromtype = TREE_TYPE (expr);
2705 tree ctors = NULL_TREE;
2706 tree conv_fns = NULL_TREE;
2707 conversion *conv = NULL;
2708 tree args = NULL_TREE;
2712 /* We represent conversion within a hierarchy using RVALUE_CONV and
2713 BASE_CONV, as specified by [over.best.ics]; these become plain
2714 constructor calls, as specified in [dcl.init]. */
2715 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2716 || !DERIVED_FROM_P (totype, fromtype));
2718 if (MAYBE_CLASS_TYPE_P (totype))
2719 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2721 if (MAYBE_CLASS_TYPE_P (fromtype))
2723 tree to_nonref = non_reference (totype);
2724 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2725 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2726 && DERIVED_FROM_P (to_nonref, fromtype)))
2728 /* [class.conv.fct] A conversion function is never used to
2729 convert a (possibly cv-qualified) object to the (possibly
2730 cv-qualified) same object type (or a reference to it), to a
2731 (possibly cv-qualified) base class of that type (or a
2732 reference to it)... */
2735 conv_fns = lookup_conversions (fromtype);
2739 flags |= LOOKUP_NO_CONVERSION;
2741 /* It's OK to bind a temporary for converting constructor arguments, but
2742 not in converting the return value of a conversion operator. */
2743 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2744 flags &= ~LOOKUP_NO_TEMP_BIND;
2750 ctors = BASELINK_FUNCTIONS (ctors);
2752 t = build_int_cst (build_pointer_type (totype), 0);
2753 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2754 && !TYPE_HAS_LIST_CTOR (totype))
2756 args = ctor_to_list (expr);
2757 /* We still allow more conversions within an init-list. */
2758 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2759 /* But not for the copy ctor. */
2760 |LOOKUP_NO_COPY_CTOR_CONVERSION
2761 |LOOKUP_NO_NARROWING);
2764 args = build_tree_list (NULL_TREE, expr);
2765 /* We should never try to call the abstract or base constructor
2767 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2768 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2769 args = tree_cons (NULL_TREE, t, args);
2771 for (; ctors; ctors = OVL_NEXT (ctors))
2773 tree ctor = OVL_CURRENT (ctors);
2774 if (DECL_NONCONVERTING_P (ctor)
2775 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2778 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2779 cand = add_template_candidate (&candidates, ctor, totype,
2780 NULL_TREE, args, NULL_TREE,
2781 TYPE_BINFO (totype),
2782 TYPE_BINFO (totype),
2786 cand = add_function_candidate (&candidates, ctor, totype,
2787 args, TYPE_BINFO (totype),
2788 TYPE_BINFO (totype),
2793 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2795 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2796 set, then this is copy-initialization. In that case, "The
2797 result of the call is then used to direct-initialize the
2798 object that is the destination of the copy-initialization."
2801 We represent this in the conversion sequence with an
2802 rvalue conversion, which means a constructor call. */
2803 if (TREE_CODE (totype) != REFERENCE_TYPE
2804 && !(convflags & LOOKUP_NO_TEMP_BIND))
2806 = build_conv (ck_rvalue, totype, cand->second_conv);
2811 args = build_tree_list (NULL_TREE, build_this (expr));
2813 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2816 tree conversion_path = TREE_PURPOSE (conv_fns);
2818 /* If we are called to convert to a reference type, we are trying to
2819 find an lvalue binding, so don't even consider temporaries. If
2820 we don't find an lvalue binding, the caller will try again to
2821 look for a temporary binding. */
2822 if (TREE_CODE (totype) == REFERENCE_TYPE)
2823 convflags |= LOOKUP_NO_TEMP_BIND;
2825 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2827 tree fn = OVL_CURRENT (fns);
2829 /* [over.match.funcs] For conversion functions, the function
2830 is considered to be a member of the class of the implicit
2831 object argument for the purpose of defining the type of
2832 the implicit object parameter.
2834 So we pass fromtype as CTYPE to add_*_candidate. */
2836 if (TREE_CODE (fn) == TEMPLATE_DECL)
2837 cand = add_template_candidate (&candidates, fn, fromtype,
2840 TYPE_BINFO (fromtype),
2845 cand = add_function_candidate (&candidates, fn, fromtype,
2847 TYPE_BINFO (fromtype),
2854 = implicit_conversion (totype,
2855 TREE_TYPE (TREE_TYPE (cand->fn)),
2857 /*c_cast_p=*/false, convflags);
2859 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2860 copy-initialization. In that case, "The result of the
2861 call is then used to direct-initialize the object that is
2862 the destination of the copy-initialization." [dcl.init]
2864 We represent this in the conversion sequence with an
2865 rvalue conversion, which means a constructor call. But
2866 don't add a second rvalue conversion if there's already
2867 one there. Which there really shouldn't be, but it's
2868 harmless since we'd add it here anyway. */
2869 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2870 && !(convflags & LOOKUP_NO_TEMP_BIND))
2871 ics = build_conv (ck_rvalue, totype, ics);
2873 cand->second_conv = ics;
2877 else if (candidates->viable == 1 && ics->bad_p)
2883 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2887 cand = tourney (candidates);
2890 if (flags & LOOKUP_COMPLAIN)
2892 error ("conversion from %qT to %qT is ambiguous",
2894 print_z_candidates (candidates);
2897 cand = candidates; /* any one will do */
2898 cand->second_conv = build_ambiguous_conv (totype, expr);
2899 cand->second_conv->user_conv_p = true;
2900 if (!any_strictly_viable (candidates))
2901 cand->second_conv->bad_p = true;
2902 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2903 ambiguous conversion is no worse than another user-defined
2909 /* Build the user conversion sequence. */
2912 (DECL_CONSTRUCTOR_P (cand->fn)
2913 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2914 build_identity_conv (TREE_TYPE (expr), expr));
2917 /* Remember that this was a list-initialization. */
2918 if (flags & LOOKUP_NO_NARROWING)
2919 conv->check_narrowing = true;
2921 /* Combine it with the second conversion sequence. */
2922 cand->second_conv = merge_conversion_sequences (conv,
2925 if (cand->viable == -1)
2926 cand->second_conv->bad_p = true;
2932 build_user_type_conversion (tree totype, tree expr, int flags)
2934 struct z_candidate *cand
2935 = build_user_type_conversion_1 (totype, expr, flags);
2939 if (cand->second_conv->kind == ck_ambig)
2940 return error_mark_node;
2941 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
2942 return convert_from_reference (expr);
2947 /* Do any initial processing on the arguments to a function call. */
2950 resolve_args (tree args)
2953 for (t = args; t; t = TREE_CHAIN (t))
2955 tree arg = TREE_VALUE (t);
2957 if (error_operand_p (arg))
2958 return error_mark_node;
2959 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2961 error ("invalid use of void expression");
2962 return error_mark_node;
2964 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
2965 return error_mark_node;
2970 /* Perform overload resolution on FN, which is called with the ARGS.
2972 Return the candidate function selected by overload resolution, or
2973 NULL if the event that overload resolution failed. In the case
2974 that overload resolution fails, *CANDIDATES will be the set of
2975 candidates considered, and ANY_VIABLE_P will be set to true or
2976 false to indicate whether or not any of the candidates were
2979 The ARGS should already have gone through RESOLVE_ARGS before this
2980 function is called. */
2982 static struct z_candidate *
2983 perform_overload_resolution (tree fn,
2985 struct z_candidate **candidates,
2988 struct z_candidate *cand;
2989 tree explicit_targs = NULL_TREE;
2990 int template_only = 0;
2993 *any_viable_p = true;
2995 /* Check FN and ARGS. */
2996 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2997 || TREE_CODE (fn) == TEMPLATE_DECL
2998 || TREE_CODE (fn) == OVERLOAD
2999 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3000 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
3002 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3004 explicit_targs = TREE_OPERAND (fn, 1);
3005 fn = TREE_OPERAND (fn, 0);
3009 /* Add the various candidate functions. */
3010 add_candidates (fn, args, explicit_targs, template_only,
3011 /*conversion_path=*/NULL_TREE,
3012 /*access_path=*/NULL_TREE,
3016 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3020 cand = tourney (*candidates);
3024 /* Return an expression for a call to FN (a namespace-scope function,
3025 or a static member function) with the ARGS. */
3028 build_new_function_call (tree fn, tree args, bool koenig_p,
3029 tsubst_flags_t complain)
3031 struct z_candidate *candidates, *cand;
3036 args = resolve_args (args);
3037 if (args == error_mark_node)
3038 return error_mark_node;
3040 /* If this function was found without using argument dependent
3041 lookup, then we want to ignore any undeclared friend
3047 fn = remove_hidden_names (fn);
3050 if (complain & tf_error)
3051 error ("no matching function for call to %<%D(%A)%>",
3052 DECL_NAME (OVL_CURRENT (orig_fn)), args);
3053 return error_mark_node;
3057 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3058 p = conversion_obstack_alloc (0);
3060 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
3064 if (complain & tf_error)
3066 if (!any_viable_p && candidates && ! candidates->next)
3067 return cp_build_function_call (candidates->fn, args, complain);
3068 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3069 fn = TREE_OPERAND (fn, 0);
3071 error ("no matching function for call to %<%D(%A)%>",
3072 DECL_NAME (OVL_CURRENT (fn)), args);
3074 error ("call of overloaded %<%D(%A)%> is ambiguous",
3075 DECL_NAME (OVL_CURRENT (fn)), args);
3077 print_z_candidates (candidates);
3079 result = error_mark_node;
3082 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3084 /* Free all the conversions we allocated. */
3085 obstack_free (&conversion_obstack, p);
3090 /* Build a call to a global operator new. FNNAME is the name of the
3091 operator (either "operator new" or "operator new[]") and ARGS are
3092 the arguments provided. *SIZE points to the total number of bytes
3093 required by the allocation, and is updated if that is changed here.
3094 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
3095 function determines that no cookie should be used, after all,
3096 *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be
3097 set, upon return, to the allocation function called. */
3100 build_operator_new_call (tree fnname, tree args,
3101 tree *size, tree *cookie_size,
3105 struct z_candidate *candidates;
3106 struct z_candidate *cand;
3111 args = tree_cons (NULL_TREE, *size, args);
3112 args = resolve_args (args);
3113 if (args == error_mark_node)
3120 If this lookup fails to find the name, or if the allocated type
3121 is not a class type, the allocation function's name is looked
3122 up in the global scope.
3124 we disregard block-scope declarations of "operator new". */
3125 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
3127 /* Figure out what function is being called. */
3128 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
3130 /* If no suitable function could be found, issue an error message
3135 error ("no matching function for call to %<%D(%A)%>",
3136 DECL_NAME (OVL_CURRENT (fns)), args);
3138 error ("call of overloaded %<%D(%A)%> is ambiguous",
3139 DECL_NAME (OVL_CURRENT (fns)), args);
3141 print_z_candidates (candidates);
3142 return error_mark_node;
3145 /* If a cookie is required, add some extra space. Whether
3146 or not a cookie is required cannot be determined until
3147 after we know which function was called. */
3150 bool use_cookie = true;
3151 if (!abi_version_at_least (2))
3153 tree placement = TREE_CHAIN (args);
3154 /* In G++ 3.2, the check was implemented incorrectly; it
3155 looked at the placement expression, rather than the
3156 type of the function. */
3157 if (placement && !TREE_CHAIN (placement)
3158 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
3166 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3167 /* Skip the size_t parameter. */
3168 arg_types = TREE_CHAIN (arg_types);
3169 /* Check the remaining parameters (if any). */
3171 && TREE_CHAIN (arg_types) == void_list_node
3172 && same_type_p (TREE_VALUE (arg_types),
3176 /* If we need a cookie, adjust the number of bytes allocated. */
3179 /* Update the total size. */
3180 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3181 /* Update the argument list to reflect the adjusted size. */
3182 TREE_VALUE (args) = *size;
3185 *cookie_size = NULL_TREE;
3188 /* Tell our caller which function we decided to call. */
3192 /* Build the CALL_EXPR. */
3193 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3197 build_object_call (tree obj, tree args, tsubst_flags_t complain)
3199 struct z_candidate *candidates = 0, *cand;
3200 tree fns, convs, mem_args = NULL_TREE;
3201 tree type = TREE_TYPE (obj);
3203 tree result = NULL_TREE;
3206 if (TYPE_PTRMEMFUNC_P (type))
3208 if (complain & tf_error)
3209 /* It's no good looking for an overloaded operator() on a
3210 pointer-to-member-function. */
3211 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3212 return error_mark_node;
3215 if (TYPE_BINFO (type))
3217 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3218 if (fns == error_mark_node)
3219 return error_mark_node;
3224 args = resolve_args (args);
3226 if (args == error_mark_node)
3227 return error_mark_node;
3229 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3230 p = conversion_obstack_alloc (0);
3234 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3235 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
3237 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3239 tree fn = OVL_CURRENT (fns);
3240 if (TREE_CODE (fn) == TEMPLATE_DECL)
3241 add_template_candidate (&candidates, fn, base, NULL_TREE,
3242 mem_args, NULL_TREE,
3245 LOOKUP_NORMAL, DEDUCE_CALL);
3247 add_function_candidate
3248 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
3249 TYPE_BINFO (type), LOOKUP_NORMAL);
3253 convs = lookup_conversions (type);
3255 for (; convs; convs = TREE_CHAIN (convs))
3257 tree fns = TREE_VALUE (convs);
3258 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
3260 if ((TREE_CODE (totype) == POINTER_TYPE
3261 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3262 || (TREE_CODE (totype) == REFERENCE_TYPE
3263 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3264 || (TREE_CODE (totype) == REFERENCE_TYPE
3265 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3266 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3267 for (; fns; fns = OVL_NEXT (fns))
3269 tree fn = OVL_CURRENT (fns);
3270 if (TREE_CODE (fn) == TEMPLATE_DECL)
3271 add_template_conv_candidate
3272 (&candidates, fn, obj, args, totype,
3273 /*access_path=*/NULL_TREE,
3274 /*conversion_path=*/NULL_TREE);
3276 add_conv_candidate (&candidates, fn, obj, args,
3277 /*conversion_path=*/NULL_TREE,
3278 /*access_path=*/NULL_TREE);
3282 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3285 if (complain & tf_error)
3287 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3288 print_z_candidates (candidates);
3290 result = error_mark_node;
3294 cand = tourney (candidates);
3297 if (complain & tf_error)
3299 error ("call of %<(%T) (%A)%> is ambiguous",
3300 TREE_TYPE (obj), args);
3301 print_z_candidates (candidates);
3303 result = error_mark_node;
3305 /* Since cand->fn will be a type, not a function, for a conversion
3306 function, we must be careful not to unconditionally look at
3308 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3309 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3310 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3313 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3315 obj = convert_from_reference (obj);
3316 result = cp_build_function_call (obj, args, complain);
3320 /* Free all the conversions we allocated. */
3321 obstack_free (&conversion_obstack, p);
3327 op_error (enum tree_code code, enum tree_code code2,
3328 tree arg1, tree arg2, tree arg3, const char *problem)
3332 if (code == MODIFY_EXPR)
3333 opname = assignment_operator_name_info[code2].name;
3335 opname = operator_name_info[code].name;
3340 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3341 problem, arg1, arg2, arg3);
3344 case POSTINCREMENT_EXPR:
3345 case POSTDECREMENT_EXPR:
3346 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3350 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3355 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3360 error ("%s for %<operator%s%> in %<%E %s %E%>",
3361 problem, opname, arg1, opname, arg2);
3363 error ("%s for %<operator%s%> in %<%s%E%>",
3364 problem, opname, opname, arg1);
3369 /* Return the implicit conversion sequence that could be used to
3370 convert E1 to E2 in [expr.cond]. */
3373 conditional_conversion (tree e1, tree e2)
3375 tree t1 = non_reference (TREE_TYPE (e1));
3376 tree t2 = non_reference (TREE_TYPE (e2));
3382 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3383 implicitly converted (clause _conv_) to the type "reference to
3384 T2", subject to the constraint that in the conversion the
3385 reference must bind directly (_dcl.init.ref_) to E1. */
3386 if (real_lvalue_p (e2))
3388 conv = implicit_conversion (build_reference_type (t2),
3392 LOOKUP_NO_TEMP_BIND);
3399 If E1 and E2 have class type, and the underlying class types are
3400 the same or one is a base class of the other: E1 can be converted
3401 to match E2 if the class of T2 is the same type as, or a base
3402 class of, the class of T1, and the cv-qualification of T2 is the
3403 same cv-qualification as, or a greater cv-qualification than, the
3404 cv-qualification of T1. If the conversion is applied, E1 is
3405 changed to an rvalue of type T2 that still refers to the original
3406 source class object (or the appropriate subobject thereof). */
3407 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3408 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3410 if (good_base && at_least_as_qualified_p (t2, t1))
3412 conv = build_identity_conv (t1, e1);
3413 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3414 TYPE_MAIN_VARIANT (t2)))
3415 conv = build_conv (ck_base, t2, conv);
3417 conv = build_conv (ck_rvalue, t2, conv);
3426 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3427 converted to the type that expression E2 would have if E2 were
3428 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3429 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3433 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3434 arguments to the conditional expression. */
3437 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3438 tsubst_flags_t complain)
3442 tree result = NULL_TREE;
3443 tree result_type = NULL_TREE;
3444 bool lvalue_p = true;
3445 struct z_candidate *candidates = 0;
3446 struct z_candidate *cand;
3449 /* As a G++ extension, the second argument to the conditional can be
3450 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3451 c'.) If the second operand is omitted, make sure it is
3452 calculated only once. */
3455 if (complain & tf_error)
3456 pedwarn (input_location, OPT_pedantic,
3457 "ISO C++ forbids omitting the middle term of a ?: expression");
3459 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3460 if (real_lvalue_p (arg1))
3461 arg2 = arg1 = stabilize_reference (arg1);
3463 arg2 = arg1 = save_expr (arg1);
3468 The first expression is implicitly converted to bool (clause
3470 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3472 /* If something has already gone wrong, just pass that fact up the
3474 if (error_operand_p (arg1)
3475 || error_operand_p (arg2)
3476 || error_operand_p (arg3))
3477 return error_mark_node;
3481 If either the second or the third operand has type (possibly
3482 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3483 array-to-pointer (_conv.array_), and function-to-pointer
3484 (_conv.func_) standard conversions are performed on the second
3485 and third operands. */
3486 arg2_type = unlowered_expr_type (arg2);
3487 arg3_type = unlowered_expr_type (arg3);
3488 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3490 /* Do the conversions. We don't these for `void' type arguments
3491 since it can't have any effect and since decay_conversion
3492 does not handle that case gracefully. */
3493 if (!VOID_TYPE_P (arg2_type))
3494 arg2 = decay_conversion (arg2);
3495 if (!VOID_TYPE_P (arg3_type))
3496 arg3 = decay_conversion (arg3);
3497 arg2_type = TREE_TYPE (arg2);
3498 arg3_type = TREE_TYPE (arg3);
3502 One of the following shall hold:
3504 --The second or the third operand (but not both) is a
3505 throw-expression (_except.throw_); the result is of the
3506 type of the other and is an rvalue.
3508 --Both the second and the third operands have type void; the
3509 result is of type void and is an rvalue.
3511 We must avoid calling force_rvalue for expressions of type
3512 "void" because it will complain that their value is being
3514 if (TREE_CODE (arg2) == THROW_EXPR
3515 && TREE_CODE (arg3) != THROW_EXPR)
3517 if (!VOID_TYPE_P (arg3_type))
3518 arg3 = force_rvalue (arg3);
3519 arg3_type = TREE_TYPE (arg3);
3520 result_type = arg3_type;
3522 else if (TREE_CODE (arg2) != THROW_EXPR
3523 && TREE_CODE (arg3) == THROW_EXPR)
3525 if (!VOID_TYPE_P (arg2_type))
3526 arg2 = force_rvalue (arg2);
3527 arg2_type = TREE_TYPE (arg2);
3528 result_type = arg2_type;
3530 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3531 result_type = void_type_node;
3534 if (complain & tf_error)
3536 if (VOID_TYPE_P (arg2_type))
3537 error ("second operand to the conditional operator "
3538 "is of type %<void%>, "
3539 "but the third operand is neither a throw-expression "
3540 "nor of type %<void%>");
3542 error ("third operand to the conditional operator "
3543 "is of type %<void%>, "
3544 "but the second operand is neither a throw-expression "
3545 "nor of type %<void%>");
3547 return error_mark_node;
3551 goto valid_operands;
3555 Otherwise, if the second and third operand have different types,
3556 and either has (possibly cv-qualified) class type, an attempt is
3557 made to convert each of those operands to the type of the other. */
3558 else if (!same_type_p (arg2_type, arg3_type)
3559 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3564 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3565 p = conversion_obstack_alloc (0);
3567 conv2 = conditional_conversion (arg2, arg3);
3568 conv3 = conditional_conversion (arg3, arg2);
3572 If both can be converted, or one can be converted but the
3573 conversion is ambiguous, the program is ill-formed. If
3574 neither can be converted, the operands are left unchanged and
3575 further checking is performed as described below. If exactly
3576 one conversion is possible, that conversion is applied to the
3577 chosen operand and the converted operand is used in place of
3578 the original operand for the remainder of this section. */
3579 if ((conv2 && !conv2->bad_p
3580 && conv3 && !conv3->bad_p)
3581 || (conv2 && conv2->kind == ck_ambig)
3582 || (conv3 && conv3->kind == ck_ambig))
3584 error ("operands to ?: have different types %qT and %qT",
3585 arg2_type, arg3_type);
3586 result = error_mark_node;
3588 else if (conv2 && (!conv2->bad_p || !conv3))
3590 arg2 = convert_like (conv2, arg2, complain);
3591 arg2 = convert_from_reference (arg2);
3592 arg2_type = TREE_TYPE (arg2);
3593 /* Even if CONV2 is a valid conversion, the result of the
3594 conversion may be invalid. For example, if ARG3 has type
3595 "volatile X", and X does not have a copy constructor
3596 accepting a "volatile X&", then even if ARG2 can be
3597 converted to X, the conversion will fail. */
3598 if (error_operand_p (arg2))
3599 result = error_mark_node;
3601 else if (conv3 && (!conv3->bad_p || !conv2))
3603 arg3 = convert_like (conv3, arg3, complain);
3604 arg3 = convert_from_reference (arg3);
3605 arg3_type = TREE_TYPE (arg3);
3606 if (error_operand_p (arg3))
3607 result = error_mark_node;
3610 /* Free all the conversions we allocated. */
3611 obstack_free (&conversion_obstack, p);
3616 /* If, after the conversion, both operands have class type,
3617 treat the cv-qualification of both operands as if it were the
3618 union of the cv-qualification of the operands.
3620 The standard is not clear about what to do in this
3621 circumstance. For example, if the first operand has type
3622 "const X" and the second operand has a user-defined
3623 conversion to "volatile X", what is the type of the second
3624 operand after this step? Making it be "const X" (matching
3625 the first operand) seems wrong, as that discards the
3626 qualification without actually performing a copy. Leaving it
3627 as "volatile X" seems wrong as that will result in the
3628 conditional expression failing altogether, even though,
3629 according to this step, the one operand could be converted to
3630 the type of the other. */
3631 if ((conv2 || conv3)
3632 && CLASS_TYPE_P (arg2_type)
3633 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3634 arg2_type = arg3_type =
3635 cp_build_qualified_type (arg2_type,
3636 TYPE_QUALS (arg2_type)
3637 | TYPE_QUALS (arg3_type));
3642 If the second and third operands are lvalues and have the same
3643 type, the result is of that type and is an lvalue. */
3644 if (real_lvalue_p (arg2)
3645 && real_lvalue_p (arg3)
3646 && same_type_p (arg2_type, arg3_type))
3648 result_type = arg2_type;
3649 goto valid_operands;
3654 Otherwise, the result is an rvalue. If the second and third
3655 operand do not have the same type, and either has (possibly
3656 cv-qualified) class type, overload resolution is used to
3657 determine the conversions (if any) to be applied to the operands
3658 (_over.match.oper_, _over.built_). */
3660 if (!same_type_p (arg2_type, arg3_type)
3661 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3667 /* Rearrange the arguments so that add_builtin_candidate only has
3668 to know about two args. In build_builtin_candidates, the
3669 arguments are unscrambled. */
3673 add_builtin_candidates (&candidates,
3676 ansi_opname (COND_EXPR),
3682 If the overload resolution fails, the program is
3684 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3687 if (complain & tf_error)
3689 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3690 print_z_candidates (candidates);
3692 return error_mark_node;
3694 cand = tourney (candidates);
3697 if (complain & tf_error)
3699 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3700 print_z_candidates (candidates);
3702 return error_mark_node;
3707 Otherwise, the conversions thus determined are applied, and
3708 the converted operands are used in place of the original
3709 operands for the remainder of this section. */
3710 conv = cand->convs[0];
3711 arg1 = convert_like (conv, arg1, complain);
3712 conv = cand->convs[1];
3713 arg2 = convert_like (conv, arg2, complain);
3714 conv = cand->convs[2];
3715 arg3 = convert_like (conv, arg3, complain);
3720 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3721 and function-to-pointer (_conv.func_) standard conversions are
3722 performed on the second and third operands.
3724 We need to force the lvalue-to-rvalue conversion here for class types,
3725 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3726 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3729 arg2 = force_rvalue (arg2);
3730 if (!CLASS_TYPE_P (arg2_type))
3731 arg2_type = TREE_TYPE (arg2);
3733 arg3 = force_rvalue (arg3);
3734 if (!CLASS_TYPE_P (arg2_type))
3735 arg3_type = TREE_TYPE (arg3);
3737 if (arg2 == error_mark_node || arg3 == error_mark_node)
3738 return error_mark_node;
3742 After those conversions, one of the following shall hold:
3744 --The second and third operands have the same type; the result is of
3746 if (same_type_p (arg2_type, arg3_type))
3747 result_type = arg2_type;
3750 --The second and third operands have arithmetic or enumeration
3751 type; the usual arithmetic conversions are performed to bring
3752 them to a common type, and the result is of that type. */
3753 else if ((ARITHMETIC_TYPE_P (arg2_type)
3754 || UNSCOPED_ENUM_P (arg2_type))
3755 && (ARITHMETIC_TYPE_P (arg3_type)
3756 || UNSCOPED_ENUM_P (arg3_type)))
3758 /* In this case, there is always a common type. */
3759 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3762 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3763 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3765 if (complain & tf_warning)
3767 "enumeral mismatch in conditional expression: %qT vs %qT",
3768 arg2_type, arg3_type);
3770 else if (extra_warnings
3771 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3772 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3773 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3774 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3776 if (complain & tf_warning)
3778 "enumeral and non-enumeral type in conditional expression");
3781 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3782 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3786 --The second and third operands have pointer type, or one has
3787 pointer type and the other is a null pointer constant; pointer
3788 conversions (_conv.ptr_) and qualification conversions
3789 (_conv.qual_) are performed to bring them to their composite
3790 pointer type (_expr.rel_). The result is of the composite
3793 --The second and third operands have pointer to member type, or
3794 one has pointer to member type and the other is a null pointer
3795 constant; pointer to member conversions (_conv.mem_) and
3796 qualification conversions (_conv.qual_) are performed to bring
3797 them to a common type, whose cv-qualification shall match the
3798 cv-qualification of either the second or the third operand.
3799 The result is of the common type. */
3800 else if ((null_ptr_cst_p (arg2)
3801 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3802 || (null_ptr_cst_p (arg3)
3803 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3804 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3805 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3806 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3808 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3809 arg3, "conditional expression",
3811 if (result_type == error_mark_node)
3812 return error_mark_node;
3813 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3814 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3819 if (complain & tf_error)
3820 error ("operands to ?: have different types %qT and %qT",
3821 arg2_type, arg3_type);
3822 return error_mark_node;
3826 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3828 /* We can't use result_type below, as fold might have returned a
3833 /* Expand both sides into the same slot, hopefully the target of
3834 the ?: expression. We used to check for TARGET_EXPRs here,
3835 but now we sometimes wrap them in NOP_EXPRs so the test would
3837 if (CLASS_TYPE_P (TREE_TYPE (result)))
3838 result = get_target_expr (result);
3839 /* If this expression is an rvalue, but might be mistaken for an
3840 lvalue, we must add a NON_LVALUE_EXPR. */
3841 result = rvalue (result);
3847 /* OPERAND is an operand to an expression. Perform necessary steps
3848 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3852 prep_operand (tree operand)
3856 if (CLASS_TYPE_P (TREE_TYPE (operand))
3857 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3858 /* Make sure the template type is instantiated now. */
3859 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3865 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3866 OVERLOAD) to the CANDIDATES, returning an updated list of
3867 CANDIDATES. The ARGS are the arguments provided to the call,
3868 without any implicit object parameter. The EXPLICIT_TARGS are
3869 explicit template arguments provided. TEMPLATE_ONLY is true if
3870 only template functions should be considered. CONVERSION_PATH,
3871 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3874 add_candidates (tree fns, tree args,
3875 tree explicit_targs, bool template_only,
3876 tree conversion_path, tree access_path,
3878 struct z_candidate **candidates)
3881 tree non_static_args;
3883 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3884 /* Delay creating the implicit this parameter until it is needed. */
3885 non_static_args = NULL_TREE;
3892 fn = OVL_CURRENT (fns);
3893 /* Figure out which set of arguments to use. */
3894 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3896 /* If this function is a non-static member, prepend the implicit
3897 object parameter. */
3898 if (!non_static_args)
3899 non_static_args = tree_cons (NULL_TREE,
3900 build_this (TREE_VALUE (args)),
3902 fn_args = non_static_args;
3905 /* Otherwise, just use the list of arguments provided. */
3908 if (TREE_CODE (fn) == TEMPLATE_DECL)
3909 add_template_candidate (candidates,
3919 else if (!template_only)
3920 add_function_candidate (candidates,
3927 fns = OVL_NEXT (fns);
3932 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3933 bool *overloaded_p, tsubst_flags_t complain)
3935 struct z_candidate *candidates = 0, *cand;
3936 tree arglist, fnname;
3938 tree result = NULL_TREE;
3939 bool result_valid_p = false;
3940 enum tree_code code2 = NOP_EXPR;
3945 bool expl_eq_arg1 = false;
3947 if (error_operand_p (arg1)
3948 || error_operand_p (arg2)
3949 || error_operand_p (arg3))
3950 return error_mark_node;
3952 if (code == MODIFY_EXPR)
3954 code2 = TREE_CODE (arg3);
3956 fnname = ansi_assopname (code2);
3959 fnname = ansi_opname (code);
3961 arg1 = prep_operand (arg1);
3967 case VEC_DELETE_EXPR:
3969 /* Use build_op_new_call and build_op_delete_call instead. */
3973 return build_object_call (arg1, arg2, complain);
3975 case TRUTH_ORIF_EXPR:
3976 case TRUTH_ANDIF_EXPR:
3977 case TRUTH_AND_EXPR:
3979 if (COMPARISON_CLASS_P (arg1))
3980 expl_eq_arg1 = true;
3985 arg2 = prep_operand (arg2);
3986 arg3 = prep_operand (arg3);
3988 if (code == COND_EXPR)
3990 if (arg2 == NULL_TREE
3991 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3992 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3993 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3994 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3997 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3998 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4001 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4002 arg2 = integer_zero_node;
4004 arglist = NULL_TREE;
4006 arglist = tree_cons (NULL_TREE, arg3, arglist);
4008 arglist = tree_cons (NULL_TREE, arg2, arglist);
4009 arglist = tree_cons (NULL_TREE, arg1, arglist);
4011 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4012 p = conversion_obstack_alloc (0);
4014 /* Add namespace-scope operators to the list of functions to
4016 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4017 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4018 flags, &candidates);
4019 /* Add class-member operators to the candidate set. */
4020 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4024 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4025 if (fns == error_mark_node)
4027 result = error_mark_node;
4028 goto user_defined_result_ready;
4031 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4033 BASELINK_BINFO (fns),
4034 TYPE_BINFO (TREE_TYPE (arg1)),
4035 flags, &candidates);
4038 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
4039 to know about two args; a builtin candidate will always have a first
4040 parameter of type bool. We'll handle that in
4041 build_builtin_candidate. */
4042 if (code == COND_EXPR)
4052 args[2] = NULL_TREE;
4055 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4061 /* For these, the built-in candidates set is empty
4062 [over.match.oper]/3. We don't want non-strict matches
4063 because exact matches are always possible with built-in
4064 operators. The built-in candidate set for COMPONENT_REF
4065 would be empty too, but since there are no such built-in
4066 operators, we accept non-strict matches for them. */
4071 strict_p = pedantic;
4075 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4080 case POSTINCREMENT_EXPR:
4081 case POSTDECREMENT_EXPR:
4082 /* Don't try anything fancy if we're not allowed to produce
4084 if (!(complain & tf_error))
4085 return error_mark_node;
4087 /* Look for an `operator++ (int)'. If they didn't have
4088 one, then we fall back to the old way of doing things. */
4089 if (flags & LOOKUP_COMPLAIN)
4090 permerror (input_location, "no %<%D(int)%> declared for postfix %qs, "
4091 "trying prefix operator instead",
4093 operator_name_info[code].name);
4094 if (code == POSTINCREMENT_EXPR)
4095 code = PREINCREMENT_EXPR;
4097 code = PREDECREMENT_EXPR;
4098 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4099 overloaded_p, complain);
4102 /* The caller will deal with these. */
4107 result_valid_p = true;
4111 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4113 /* If one of the arguments of the operator represents
4114 an invalid use of member function pointer, try to report
4115 a meaningful error ... */
4116 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4117 || invalid_nonstatic_memfn_p (arg2, tf_error)
4118 || invalid_nonstatic_memfn_p (arg3, tf_error))
4119 /* We displayed the error message. */;
4122 /* ... Otherwise, report the more generic
4123 "no matching operator found" error */
4124 op_error (code, code2, arg1, arg2, arg3, "no match");
4125 print_z_candidates (candidates);
4128 result = error_mark_node;
4134 cand = tourney (candidates);
4137 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4139 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4140 print_z_candidates (candidates);
4142 result = error_mark_node;
4144 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4147 *overloaded_p = true;
4149 if (resolve_args (arglist) == error_mark_node)
4150 result = error_mark_node;
4152 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4156 /* Give any warnings we noticed during overload resolution. */
4157 if (cand->warnings && (complain & tf_warning))
4159 struct candidate_warning *w;
4160 for (w = cand->warnings; w; w = w->next)
4161 joust (cand, w->loser, 1);
4164 /* Check for comparison of different enum types. */
4173 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4174 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4175 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4176 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4177 && (complain & tf_warning))
4179 warning (OPT_Wenum_compare,
4180 "comparison between %q#T and %q#T",
4181 TREE_TYPE (arg1), TREE_TYPE (arg2));
4188 /* We need to strip any leading REF_BIND so that bitfields
4189 don't cause errors. This should not remove any important
4190 conversions, because builtins don't apply to class
4191 objects directly. */
4192 conv = cand->convs[0];
4193 if (conv->kind == ck_ref_bind)
4194 conv = conv->u.next;
4195 arg1 = convert_like (conv, arg1, complain);
4198 conv = cand->convs[1];
4199 if (conv->kind == ck_ref_bind)
4200 conv = conv->u.next;
4201 arg2 = convert_like (conv, arg2, complain);
4205 conv = cand->convs[2];
4206 if (conv->kind == ck_ref_bind)
4207 conv = conv->u.next;
4208 arg3 = convert_like (conv, arg3, complain);
4213 if (complain & tf_warning)
4214 warn_logical_operator (code, arg1, arg2);
4215 expl_eq_arg1 = true;
4220 user_defined_result_ready:
4222 /* Free all the conversions we allocated. */
4223 obstack_free (&conversion_obstack, p);
4225 if (result || result_valid_p)
4232 return cp_build_modify_expr (arg1, code2, arg2, complain);
4235 return cp_build_indirect_ref (arg1, "unary *", complain);
4237 case TRUTH_ANDIF_EXPR:
4238 case TRUTH_ORIF_EXPR:
4239 case TRUTH_AND_EXPR:
4242 warn_logical_operator (code, arg1, arg2);
4246 case TRUNC_DIV_EXPR:
4257 case TRUNC_MOD_EXPR:
4261 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4263 case UNARY_PLUS_EXPR:
4266 case TRUTH_NOT_EXPR:
4267 case PREINCREMENT_EXPR:
4268 case POSTINCREMENT_EXPR:
4269 case PREDECREMENT_EXPR:
4270 case POSTDECREMENT_EXPR:
4273 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4276 return build_array_ref (arg1, arg2, input_location);
4279 return build_conditional_expr (arg1, arg2, arg3, complain);
4282 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4286 /* The caller will deal with these. */
4298 /* Build a call to operator delete. This has to be handled very specially,
4299 because the restrictions on what signatures match are different from all
4300 other call instances. For a normal delete, only a delete taking (void *)
4301 or (void *, size_t) is accepted. For a placement delete, only an exact
4302 match with the placement new is accepted.
4304 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4305 ADDR is the pointer to be deleted.
4306 SIZE is the size of the memory block to be deleted.
4307 GLOBAL_P is true if the delete-expression should not consider
4308 class-specific delete operators.
4309 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4311 If this call to "operator delete" is being generated as part to
4312 deallocate memory allocated via a new-expression (as per [expr.new]
4313 which requires that if the initialization throws an exception then
4314 we call a deallocation function), then ALLOC_FN is the allocation
4318 build_op_delete_call (enum tree_code code, tree addr, tree size,
4319 bool global_p, tree placement,
4322 tree fn = NULL_TREE;
4323 tree fns, fnname, argtypes, type;
4326 if (addr == error_mark_node)
4327 return error_mark_node;
4329 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4331 fnname = ansi_opname (code);
4333 if (CLASS_TYPE_P (type)
4334 && COMPLETE_TYPE_P (complete_type (type))
4338 If the result of the lookup is ambiguous or inaccessible, or if
4339 the lookup selects a placement deallocation function, the
4340 program is ill-formed.
4342 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4344 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4345 if (fns == error_mark_node)
4346 return error_mark_node;
4351 if (fns == NULL_TREE)
4352 fns = lookup_name_nonclass (fnname);
4354 /* Strip const and volatile from addr. */
4355 addr = cp_convert (ptr_type_node, addr);
4359 /* Get the parameter types for the allocation function that is
4361 gcc_assert (alloc_fn != NULL_TREE);
4362 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4366 /* First try it without the size argument. */
4367 argtypes = void_list_node;
4370 /* We make two tries at finding a matching `operator delete'. On
4371 the first pass, we look for a one-operator (or placement)
4372 operator delete. If we're not doing placement delete, then on
4373 the second pass we look for a two-argument delete. */
4374 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4376 /* Go through the `operator delete' functions looking for one
4377 with a matching type. */
4378 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4384 /* The first argument must be "void *". */
4385 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4386 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4389 /* On the first pass, check the rest of the arguments. */
4395 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4403 /* On the second pass, look for a function with exactly two
4404 arguments: "void *" and "size_t". */
4406 /* For "operator delete(void *, ...)" there will be
4407 no second argument, but we will not get an exact
4410 && same_type_p (TREE_VALUE (t), size_type_node)
4411 && TREE_CHAIN (t) == void_list_node)
4415 /* If we found a match, we're done. */
4420 /* If we have a matching function, call it. */
4423 /* Make sure we have the actual function, and not an
4425 fn = OVL_CURRENT (fn);
4427 /* If the FN is a member function, make sure that it is
4429 if (DECL_CLASS_SCOPE_P (fn))
4430 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4434 /* The placement args might not be suitable for overload
4435 resolution at this point, so build the call directly. */
4436 int nargs = call_expr_nargs (placement);
4437 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4440 for (i = 1; i < nargs; i++)
4441 argarray[i] = CALL_EXPR_ARG (placement, i);
4443 return build_cxx_call (fn, nargs, argarray);
4449 args = tree_cons (NULL_TREE, addr, NULL_TREE);
4451 args = tree_cons (NULL_TREE, addr,
4452 build_tree_list (NULL_TREE, size));
4453 return cp_build_function_call (fn, args, tf_warning_or_error);
4459 If no unambiguous matching deallocation function can be found,
4460 propagating the exception does not cause the object's memory to
4465 warning (0, "no corresponding deallocation function for %qD",
4470 error ("no suitable %<operator %s%> for %qT",
4471 operator_name_info[(int)code].name, type);
4472 return error_mark_node;
4475 /* If the current scope isn't allowed to access DECL along
4476 BASETYPE_PATH, give an error. The most derived class in
4477 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4478 the declaration to use in the error diagnostic. */
4481 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4483 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4485 if (!accessible_p (basetype_path, decl, true))
4487 if (TREE_PRIVATE (decl))
4488 error ("%q+#D is private", diag_decl);
4489 else if (TREE_PROTECTED (decl))
4490 error ("%q+#D is protected", diag_decl);
4492 error ("%q+#D is inaccessible", diag_decl);
4493 error ("within this context");
4500 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4501 bitwise or of LOOKUP_* values. If any errors are warnings are
4502 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4503 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4507 build_temp (tree expr, tree type, int flags,
4508 diagnostic_t *diagnostic_kind)
4512 savew = warningcount, savee = errorcount;
4513 expr = build_special_member_call (NULL_TREE,
4514 complete_ctor_identifier,
4515 build_tree_list (NULL_TREE, expr),
4516 type, flags, tf_warning_or_error);
4517 if (warningcount > savew)
4518 *diagnostic_kind = DK_WARNING;
4519 else if (errorcount > savee)
4520 *diagnostic_kind = DK_ERROR;
4522 *diagnostic_kind = 0;
4526 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4527 EXPR is implicitly converted to type TOTYPE.
4528 FN and ARGNUM are used for diagnostics. */
4531 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4533 tree t = non_reference (totype);
4535 /* Issue warnings about peculiar, but valid, uses of NULL. */
4536 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4539 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4542 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4545 /* Issue warnings if "false" is converted to a NULL pointer */
4546 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4547 warning (OPT_Wconversion,
4548 "converting %<false%> to pointer type for argument %P of %qD",
4552 /* Perform the conversions in CONVS on the expression EXPR. FN and
4553 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4554 indicates the `this' argument of a method. INNER is nonzero when
4555 being called to continue a conversion chain. It is negative when a
4556 reference binding will be applied, positive otherwise. If
4557 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4558 conversions will be emitted if appropriate. If C_CAST_P is true,
4559 this conversion is coming from a C-style cast; in that case,
4560 conversions to inaccessible bases are permitted. */
4563 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4564 int inner, bool issue_conversion_warnings,
4565 bool c_cast_p, tsubst_flags_t complain)
4567 tree totype = convs->type;
4568 diagnostic_t diag_kind;
4572 && convs->kind != ck_user
4573 && convs->kind != ck_list
4574 && convs->kind != ck_ambig
4575 && convs->kind != ck_ref_bind
4576 && convs->kind != ck_rvalue
4577 && convs->kind != ck_base)
4579 conversion *t = convs;
4581 /* Give a helpful error if this is bad because of excess braces. */
4582 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4583 && SCALAR_TYPE_P (totype)
4584 && CONSTRUCTOR_NELTS (expr) > 0
4585 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4586 permerror (input_location, "too many braces around initializer for %qT", totype);
4588 for (; t; t = convs->u.next)
4590 if (t->kind == ck_user || !t->bad_p)
4592 expr = convert_like_real (t, expr, fn, argnum, 1,
4593 /*issue_conversion_warnings=*/false,
4598 else if (t->kind == ck_ambig)
4599 return convert_like_real (t, expr, fn, argnum, 1,
4600 /*issue_conversion_warnings=*/false,
4603 else if (t->kind == ck_identity)
4606 if (complain & tf_error)
4608 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4610 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4613 return error_mark_node;
4615 return cp_convert (totype, expr);
4618 if (issue_conversion_warnings && (complain & tf_warning))
4619 conversion_null_warnings (totype, expr, fn, argnum);
4621 switch (convs->kind)
4625 struct z_candidate *cand = convs->cand;
4626 tree convfn = cand->fn;
4629 /* When converting from an init list we consider explicit
4630 constructors, but actually trying to call one is an error. */
4631 if (DECL_NONCONVERTING_P (convfn))
4633 if (complain & tf_error)
4634 error ("converting to %qT from initializer list would use "
4635 "explicit constructor %qD", totype, convfn);
4637 return error_mark_node;
4640 /* Set user_conv_p on the argument conversions, so rvalue/base
4641 handling knows not to allow any more UDCs. */
4642 for (i = 0; i < cand->num_convs; ++i)
4643 cand->convs[i]->user_conv_p = true;
4645 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4647 /* If this is a constructor or a function returning an aggr type,
4648 we need to build up a TARGET_EXPR. */
4649 if (DECL_CONSTRUCTOR_P (convfn))
4651 expr = build_cplus_new (totype, expr);
4653 /* Remember that this was list-initialization. */
4654 if (convs->check_narrowing)
4655 TARGET_EXPR_LIST_INIT_P (expr) = true;
4661 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4663 int nelts = CONSTRUCTOR_NELTS (expr);
4665 expr = integer_zero_node;
4666 else if (nelts == 1)
4667 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4672 if (type_unknown_p (expr))
4673 expr = instantiate_type (totype, expr, complain);
4674 /* Convert a constant to its underlying value, unless we are
4675 about to bind it to a reference, in which case we need to
4676 leave it as an lvalue. */
4679 expr = decl_constant_value (expr);
4680 if (expr == null_node && INTEGRAL_TYPE_P (totype))
4681 /* If __null has been converted to an integer type, we do not
4682 want to warn about uses of EXPR as an integer, rather than
4684 expr = build_int_cst (totype, 0);
4688 /* Call build_user_type_conversion again for the error. */
4689 return build_user_type_conversion
4690 (totype, convs->u.expr, LOOKUP_NORMAL);
4694 /* Conversion to std::initializer_list<T>. */
4695 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4696 tree new_ctor = build_constructor (init_list_type_node, NULL);
4697 unsigned len = CONSTRUCTOR_NELTS (expr);
4698 tree array, parms, val;
4701 /* Convert all the elements. */
4702 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4704 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4705 1, false, false, complain);
4706 if (sub == error_mark_node)
4708 check_narrowing (TREE_TYPE (sub), val);
4709 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4711 /* Build up the array. */
4712 elttype = cp_build_qualified_type
4713 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4714 array = build_array_of_n_type (elttype, len);
4715 array = finish_compound_literal (array, new_ctor);
4717 parms = build_tree_list (NULL_TREE, size_int (len));
4718 parms = tree_cons (NULL_TREE, decay_conversion (array), parms);
4719 /* Call the private constructor. */
4720 push_deferring_access_checks (dk_no_check);
4721 new_ctor = build_special_member_call
4722 (NULL_TREE, complete_ctor_identifier, parms, totype, 0, complain);
4723 pop_deferring_access_checks ();
4724 return build_cplus_new (totype, new_ctor);
4728 return get_target_expr (digest_init (totype, expr));
4734 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4735 convs->kind == ck_ref_bind ? -1 : 1,
4736 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4739 if (expr == error_mark_node)
4740 return error_mark_node;
4742 switch (convs->kind)
4745 expr = decay_conversion (expr);
4746 if (! MAYBE_CLASS_TYPE_P (totype))
4748 /* Else fall through. */
4750 if (convs->kind == ck_base && !convs->need_temporary_p)
4752 /* We are going to bind a reference directly to a base-class
4753 subobject of EXPR. */
4754 /* Build an expression for `*((base*) &expr)'. */
4755 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4756 expr = convert_to_base (expr, build_pointer_type (totype),
4757 !c_cast_p, /*nonnull=*/true);
4758 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4762 /* Copy-initialization where the cv-unqualified version of the source
4763 type is the same class as, or a derived class of, the class of the
4764 destination [is treated as direct-initialization]. [dcl.init] */
4765 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4766 if (convs->user_conv_p)
4767 /* This conversion is being done in the context of a user-defined
4768 conversion (i.e. the second step of copy-initialization), so
4769 don't allow any more. */
4770 flags |= LOOKUP_NO_CONVERSION;
4771 expr = build_temp (expr, totype, flags, &diag_kind);
4772 if (diag_kind && fn)
4774 if ((complain & tf_error))
4775 emit_diagnostic (diag_kind, input_location, 0,
4776 " initializing argument %P of %qD", argnum, fn);
4777 else if (diag_kind == DK_ERROR)
4778 return error_mark_node;
4780 return build_cplus_new (totype, expr);
4784 tree ref_type = totype;
4786 /* If necessary, create a temporary.
4788 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4789 that need temporaries, even when their types are reference
4790 compatible with the type of reference being bound, so the
4791 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
4793 if (convs->need_temporary_p
4794 || TREE_CODE (expr) == CONSTRUCTOR
4795 || TREE_CODE (expr) == VA_ARG_EXPR)
4797 tree type = convs->u.next->type;
4798 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4800 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4801 && !TYPE_REF_IS_RVALUE (ref_type))
4803 if (complain & tf_error)
4805 /* If the reference is volatile or non-const, we
4806 cannot create a temporary. */
4807 if (lvalue & clk_bitfield)
4808 error ("cannot bind bitfield %qE to %qT",
4810 else if (lvalue & clk_packed)
4811 error ("cannot bind packed field %qE to %qT",
4814 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4816 return error_mark_node;
4818 /* If the source is a packed field, and we must use a copy
4819 constructor, then building the target expr will require
4820 binding the field to the reference parameter to the
4821 copy constructor, and we'll end up with an infinite
4822 loop. If we can use a bitwise copy, then we'll be
4824 if ((lvalue & clk_packed)
4825 && CLASS_TYPE_P (type)
4826 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4828 if (complain & tf_error)
4829 error ("cannot bind packed field %qE to %qT",
4831 return error_mark_node;
4833 if (lvalue & clk_bitfield)
4835 expr = convert_bitfield_to_declared_type (expr);
4836 expr = fold_convert (type, expr);
4838 expr = build_target_expr_with_type (expr, type);
4841 /* Take the address of the thing to which we will bind the
4843 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
4844 if (expr == error_mark_node)
4845 return error_mark_node;
4847 /* Convert it to a pointer to the type referred to by the
4848 reference. This will adjust the pointer if a derived to
4849 base conversion is being performed. */
4850 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4852 /* Convert the pointer to the desired reference type. */
4853 return build_nop (ref_type, expr);
4857 return decay_conversion (expr);
4860 /* Warn about deprecated conversion if appropriate. */
4861 string_conv_p (totype, expr, 1);
4866 expr = convert_to_base (expr, totype, !c_cast_p,
4868 return build_nop (totype, expr);
4871 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4878 if (convs->check_narrowing)
4879 check_narrowing (totype, expr);
4881 if (issue_conversion_warnings && (complain & tf_warning))
4882 expr = convert_and_check (totype, expr);
4884 expr = convert (totype, expr);
4889 /* Build a call to __builtin_trap. */
4892 call_builtin_trap (void)
4894 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4896 gcc_assert (fn != NULL);
4897 fn = build_call_n (fn, 0);
4901 /* ARG is being passed to a varargs function. Perform any conversions
4902 required. Return the converted value. */
4905 convert_arg_to_ellipsis (tree arg)
4909 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4910 standard conversions are performed. */
4911 arg = decay_conversion (arg);
4914 If the argument has integral or enumeration type that is subject
4915 to the integral promotions (_conv.prom_), or a floating point
4916 type that is subject to the floating point promotion
4917 (_conv.fpprom_), the value of the argument is converted to the
4918 promoted type before the call. */
4919 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4920 && (TYPE_PRECISION (TREE_TYPE (arg))
4921 < TYPE_PRECISION (double_type_node)))
4922 arg = convert_to_real (double_type_node, arg);
4923 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4924 arg = perform_integral_promotions (arg);
4926 arg = require_complete_type (arg);
4928 if (arg != error_mark_node
4929 && !pod_type_p (TREE_TYPE (arg)))
4931 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4932 here and do a bitwise copy, but now cp_expr_size will abort if we
4934 If the call appears in the context of a sizeof expression,
4935 there is no need to emit a warning, since the expression won't be
4936 evaluated. We keep the builtin_trap just as a safety check. */
4937 if (!skip_evaluation)
4938 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4939 "call will abort at runtime", TREE_TYPE (arg));
4940 arg = call_builtin_trap ();
4941 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4948 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4951 build_x_va_arg (tree expr, tree type)
4953 if (processing_template_decl)
4954 return build_min (VA_ARG_EXPR, type, expr);
4956 type = complete_type_or_else (type, NULL_TREE);
4958 if (expr == error_mark_node || !type)
4959 return error_mark_node;
4961 if (! pod_type_p (type))
4963 /* Remove reference types so we don't ICE later on. */
4964 tree type1 = non_reference (type);
4965 /* Undefined behavior [expr.call] 5.2.2/7. */
4966 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4967 "call will abort at runtime", type);
4968 expr = convert (build_pointer_type (type1), null_node);
4969 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4970 call_builtin_trap (), expr);
4971 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
4975 return build_va_arg (expr, type);
4978 /* TYPE has been given to va_arg. Apply the default conversions which
4979 would have happened when passed via ellipsis. Return the promoted
4980 type, or the passed type if there is no change. */
4983 cxx_type_promotes_to (tree type)
4987 /* Perform the array-to-pointer and function-to-pointer
4989 type = type_decays_to (type);
4991 promote = type_promotes_to (type);
4992 if (same_type_p (type, promote))
4998 /* ARG is a default argument expression being passed to a parameter of
4999 the indicated TYPE, which is a parameter to FN. Do any required
5000 conversions. Return the converted value. */
5002 static GTY(()) VEC(tree,gc) *default_arg_context;
5005 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5010 /* If the ARG is an unparsed default argument expression, the
5011 conversion cannot be performed. */
5012 if (TREE_CODE (arg) == DEFAULT_ARG)
5014 error ("the default argument for parameter %d of %qD has "
5015 "not yet been parsed",
5017 return error_mark_node;
5020 /* Detect recursion. */
5021 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5024 error ("recursive evaluation of default argument for %q#D", fn);
5025 return error_mark_node;
5027 VEC_safe_push (tree, gc, default_arg_context, fn);
5029 if (fn && DECL_TEMPLATE_INFO (fn))
5030 arg = tsubst_default_argument (fn, type, arg);
5036 The names in the expression are bound, and the semantic
5037 constraints are checked, at the point where the default
5038 expressions appears.
5040 we must not perform access checks here. */
5041 push_deferring_access_checks (dk_no_check);
5042 arg = break_out_target_exprs (arg);
5043 if (TREE_CODE (arg) == CONSTRUCTOR)
5045 arg = digest_init (type, arg);
5046 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5047 "default argument", fn, parmnum,
5048 tf_warning_or_error);
5052 /* We must make a copy of ARG, in case subsequent processing
5053 alters any part of it. For example, during gimplification a
5054 cast of the form (T) &X::f (where "f" is a member function)
5055 will lead to replacing the PTRMEM_CST for &X::f with a
5056 VAR_DECL. We can avoid the copy for constants, since they
5057 are never modified in place. */
5058 if (!CONSTANT_CLASS_P (arg))
5059 arg = unshare_expr (arg);
5060 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5061 "default argument", fn, parmnum,
5062 tf_warning_or_error);
5063 arg = convert_for_arg_passing (type, arg);
5065 pop_deferring_access_checks();
5067 VEC_pop (tree, default_arg_context);
5072 /* Returns the type which will really be used for passing an argument of
5076 type_passed_as (tree type)
5078 /* Pass classes with copy ctors by invisible reference. */
5079 if (TREE_ADDRESSABLE (type))
5081 type = build_reference_type (type);
5082 /* There are no other pointers to this temporary. */
5083 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5085 else if (targetm.calls.promote_prototypes (type)
5086 && INTEGRAL_TYPE_P (type)
5087 && COMPLETE_TYPE_P (type)
5088 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5089 TYPE_SIZE (integer_type_node)))
5090 type = integer_type_node;
5095 /* Actually perform the appropriate conversion. */
5098 convert_for_arg_passing (tree type, tree val)
5102 /* If VAL is a bitfield, then -- since it has already been converted
5103 to TYPE -- it cannot have a precision greater than TYPE.
5105 If it has a smaller precision, we must widen it here. For
5106 example, passing "int f:3;" to a function expecting an "int" will
5107 not result in any conversion before this point.
5109 If the precision is the same we must not risk widening. For
5110 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5111 often have type "int", even though the C++ type for the field is
5112 "long long". If the value is being passed to a function
5113 expecting an "int", then no conversions will be required. But,
5114 if we call convert_bitfield_to_declared_type, the bitfield will
5115 be converted to "long long". */
5116 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5118 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5119 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5121 if (val == error_mark_node)
5123 /* Pass classes with copy ctors by invisible reference. */
5124 else if (TREE_ADDRESSABLE (type))
5125 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5126 else if (targetm.calls.promote_prototypes (type)
5127 && INTEGRAL_TYPE_P (type)
5128 && COMPLETE_TYPE_P (type)
5129 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5130 TYPE_SIZE (integer_type_node)))
5131 val = perform_integral_promotions (val);
5132 if (warn_missing_format_attribute)
5134 tree rhstype = TREE_TYPE (val);
5135 const enum tree_code coder = TREE_CODE (rhstype);
5136 const enum tree_code codel = TREE_CODE (type);
5137 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5139 && check_missing_format_attribute (type, rhstype))
5140 warning (OPT_Wmissing_format_attribute,
5141 "argument of function call might be a candidate for a format attribute");
5146 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5147 which no conversions at all should be done. This is true for some
5148 builtins which don't act like normal functions. */
5151 magic_varargs_p (tree fn)
5153 if (DECL_BUILT_IN (fn))
5154 switch (DECL_FUNCTION_CODE (fn))
5156 case BUILT_IN_CLASSIFY_TYPE:
5157 case BUILT_IN_CONSTANT_P:
5158 case BUILT_IN_NEXT_ARG:
5159 case BUILT_IN_VA_START:
5163 return lookup_attribute ("type generic",
5164 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5170 /* Subroutine of the various build_*_call functions. Overload resolution
5171 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5172 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5173 bitmask of various LOOKUP_* flags which apply to the call itself. */
5176 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5179 tree args = cand->args;
5180 conversion **convs = cand->convs;
5182 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5190 bool already_used = false;
5192 /* In a template, there is no need to perform all of the work that
5193 is normally done. We are only interested in the type of the call
5194 expression, i.e., the return type of the function. Any semantic
5195 errors will be deferred until the template is instantiated. */
5196 if (processing_template_decl)
5200 return_type = TREE_TYPE (TREE_TYPE (fn));
5201 expr = build_call_list (return_type, build_addr_func (fn), args);
5202 if (TREE_THIS_VOLATILE (fn) && cfun)
5203 current_function_returns_abnormally = 1;
5204 if (!VOID_TYPE_P (return_type))
5205 require_complete_type (return_type);
5206 return convert_from_reference (expr);
5209 /* Give any warnings we noticed during overload resolution. */
5212 struct candidate_warning *w;
5213 for (w = cand->warnings; w; w = w->next)
5214 joust (cand, w->loser, 1);
5217 /* Make =delete work with SFINAE. */
5218 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5219 return error_mark_node;
5221 if (DECL_FUNCTION_MEMBER_P (fn))
5223 /* If FN is a template function, two cases must be considered.
5228 template <class T> void f();
5230 template <class T> struct B {
5234 struct C : A, B<int> {
5236 using B<int>::g; // #2
5239 In case #1 where `A::f' is a member template, DECL_ACCESS is
5240 recorded in the primary template but not in its specialization.
5241 We check access of FN using its primary template.
5243 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5244 because it is a member of class template B, DECL_ACCESS is
5245 recorded in the specialization `B<int>::g'. We cannot use its
5246 primary template because `B<T>::g' and `B<int>::g' may have
5247 different access. */
5248 if (DECL_TEMPLATE_INFO (fn)
5249 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5250 perform_or_defer_access_check (cand->access_path,
5251 DECL_TI_TEMPLATE (fn), fn);
5253 perform_or_defer_access_check (cand->access_path, fn, fn);
5256 if (args && TREE_CODE (args) != TREE_LIST)
5257 args = build_tree_list (NULL_TREE, args);
5260 /* Find maximum size of vector to hold converted arguments. */
5261 parmlen = list_length (parm);
5262 nargs = list_length (args);
5263 if (parmlen > nargs)
5265 argarray = (tree *) alloca (nargs * sizeof (tree));
5267 /* The implicit parameters to a constructor are not considered by overload
5268 resolution, and must be of the proper type. */
5269 if (DECL_CONSTRUCTOR_P (fn))
5271 argarray[j++] = TREE_VALUE (arg);
5272 arg = TREE_CHAIN (arg);
5273 parm = TREE_CHAIN (parm);
5274 /* We should never try to call the abstract constructor. */
5275 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5277 if (DECL_HAS_VTT_PARM_P (fn))
5279 argarray[j++] = TREE_VALUE (arg);
5280 arg = TREE_CHAIN (arg);
5281 parm = TREE_CHAIN (parm);
5284 /* Bypass access control for 'this' parameter. */
5285 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5287 tree parmtype = TREE_VALUE (parm);
5288 tree argtype = TREE_TYPE (TREE_VALUE (arg));
5292 if (convs[i]->bad_p)
5294 if (complain & tf_error)
5295 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5296 TREE_TYPE (argtype), fn);
5298 return error_mark_node;
5301 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5302 X is called for an object that is not of type X, or of a type
5303 derived from X, the behavior is undefined.
5305 So we can assume that anything passed as 'this' is non-null, and
5306 optimize accordingly. */
5307 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5308 /* Convert to the base in which the function was declared. */
5309 gcc_assert (cand->conversion_path != NULL_TREE);
5310 converted_arg = build_base_path (PLUS_EXPR,
5312 cand->conversion_path,
5314 /* Check that the base class is accessible. */
5315 if (!accessible_base_p (TREE_TYPE (argtype),
5316 BINFO_TYPE (cand->conversion_path), true))
5317 error ("%qT is not an accessible base of %qT",
5318 BINFO_TYPE (cand->conversion_path),
5319 TREE_TYPE (argtype));
5320 /* If fn was found by a using declaration, the conversion path
5321 will be to the derived class, not the base declaring fn. We
5322 must convert from derived to base. */
5323 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5324 TREE_TYPE (parmtype), ba_unique, NULL);
5325 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5328 argarray[j++] = converted_arg;
5329 parm = TREE_CHAIN (parm);
5330 arg = TREE_CHAIN (arg);
5336 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
5338 tree type = TREE_VALUE (parm);
5342 /* Don't make a copy here if build_call is going to. */
5343 if (conv->kind == ck_rvalue
5344 && COMPLETE_TYPE_P (complete_type (type))
5345 && !TREE_ADDRESSABLE (type))
5346 conv = conv->u.next;
5348 /* Warn about initializer_list deduction that isn't currently in the
5350 if (cxx_dialect > cxx98
5351 && flag_deduce_init_list
5352 && cand->template_decl
5353 && is_std_init_list (non_reference (type)))
5355 tree tmpl = TI_TEMPLATE (cand->template_decl);
5356 tree realparm = DECL_ARGUMENTS (cand->fn);
5361 realparm = TREE_CHAIN (realparm);
5362 patparm = get_pattern_parm (realparm, tmpl);
5364 if (!is_std_init_list (non_reference (TREE_TYPE (patparm))))
5366 pedwarn (input_location, 0, "deducing %qT as %qT",
5367 non_reference (TREE_TYPE (patparm)),
5368 non_reference (type));
5369 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
5370 pedwarn (input_location, 0,
5371 " (you can disable this with -fno-deduce-init-list)");
5375 val = convert_like_with_context
5376 (conv, TREE_VALUE (arg), fn, i - is_method, complain);
5378 val = convert_for_arg_passing (type, val);
5379 if (val == error_mark_node)
5380 return error_mark_node;
5382 argarray[j++] = val;
5385 /* Default arguments */
5386 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5387 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5388 TREE_PURPOSE (parm),
5391 for (; arg; arg = TREE_CHAIN (arg))
5393 tree a = TREE_VALUE (arg);
5394 if (magic_varargs_p (fn))
5395 /* Do no conversions for magic varargs. */;
5397 a = convert_arg_to_ellipsis (a);
5401 gcc_assert (j <= nargs);
5404 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5405 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5407 /* Avoid actually calling copy constructors and copy assignment operators,
5410 if (! flag_elide_constructors)
5411 /* Do things the hard way. */;
5412 else if (cand->num_convs == 1
5413 && (DECL_COPY_CONSTRUCTOR_P (fn)
5414 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5417 arg = argarray[num_artificial_parms_for (fn)];
5419 /* Pull out the real argument, disregarding const-correctness. */
5421 while (CONVERT_EXPR_P (targ)
5422 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5423 targ = TREE_OPERAND (targ, 0);
5424 if (TREE_CODE (targ) == ADDR_EXPR)
5426 targ = TREE_OPERAND (targ, 0);
5427 if (!same_type_ignoring_top_level_qualifiers_p
5428 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5437 arg = cp_build_indirect_ref (arg, 0, complain);
5439 if (TREE_CODE (arg) == TARGET_EXPR
5440 && TARGET_EXPR_LIST_INIT_P (arg))
5442 /* Copy-list-initialization doesn't require the copy constructor
5445 /* [class.copy]: the copy constructor is implicitly defined even if
5446 the implementation elided its use. */
5447 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5450 already_used = true;
5453 /* If we're creating a temp and we already have one, don't create a
5454 new one. If we're not creating a temp but we get one, use
5455 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5456 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5457 temp or an INIT_EXPR otherwise. */
5458 if (integer_zerop (TREE_VALUE (args)))
5460 if (TREE_CODE (arg) == TARGET_EXPR)
5462 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5463 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5465 else if (TREE_CODE (arg) == TARGET_EXPR
5466 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5467 && !move_fn_p (fn)))
5469 tree to = stabilize_reference
5470 (cp_build_indirect_ref (TREE_VALUE (args), 0, complain));
5472 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5476 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5478 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5480 tree to = stabilize_reference
5481 (cp_build_indirect_ref (argarray[0], 0, complain));
5482 tree type = TREE_TYPE (to);
5483 tree as_base = CLASSTYPE_AS_BASE (type);
5486 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5488 arg = cp_build_indirect_ref (arg, 0, complain);
5489 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5493 /* We must only copy the non-tail padding parts.
5494 Use __builtin_memcpy for the bitwise copy.
5495 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5496 instead of an explicit call to memcpy. */
5498 tree arg0, arg1, arg2, t;
5499 tree test = NULL_TREE;
5501 arg2 = TYPE_SIZE_UNIT (as_base);
5503 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5505 if (!(optimize && flag_tree_ter))
5507 /* When TER is off get_pointer_alignment returns 0, so a call
5508 to __builtin_memcpy is expanded as a call to memcpy, which
5509 is invalid with identical args. When TER is on it is
5510 expanded as a block move, which should be safe. */
5511 arg0 = save_expr (arg0);
5512 arg1 = save_expr (arg1);
5513 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5515 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5516 t = build_call_n (t, 3, arg0, arg1, arg2);
5518 t = convert (TREE_TYPE (arg0), t);
5520 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5521 val = cp_build_indirect_ref (t, 0, complain);
5530 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5533 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5536 gcc_assert (binfo && binfo != error_mark_node);
5538 /* Warn about deprecated virtual functions now, since we're about
5539 to throw away the decl. */
5540 if (TREE_DEPRECATED (fn))
5541 warn_deprecated_use (fn);
5543 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5544 if (TREE_SIDE_EFFECTS (argarray[0]))
5545 argarray[0] = save_expr (argarray[0]);
5546 t = build_pointer_type (TREE_TYPE (fn));
5547 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5548 fn = build_java_interface_fn_ref (fn, argarray[0]);
5550 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5554 fn = build_addr_func (fn);
5556 return build_cxx_call (fn, nargs, argarray);
5559 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5560 This function performs no overload resolution, conversion, or other
5561 high-level operations. */
5564 build_cxx_call (tree fn, int nargs, tree *argarray)
5568 fn = build_call_a (fn, nargs, argarray);
5570 /* If this call might throw an exception, note that fact. */
5571 fndecl = get_callee_fndecl (fn);
5572 if ((!fndecl || !TREE_NOTHROW (fndecl))
5573 && at_function_scope_p ()
5575 cp_function_chain->can_throw = 1;
5577 /* Check that arguments to builtin functions match the expectations. */
5579 && DECL_BUILT_IN (fndecl)
5580 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5581 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5582 return error_mark_node;
5584 /* Some built-in function calls will be evaluated at compile-time in
5586 fn = fold_if_not_in_template (fn);
5588 if (VOID_TYPE_P (TREE_TYPE (fn)))
5591 fn = require_complete_type (fn);
5592 if (fn == error_mark_node)
5593 return error_mark_node;
5595 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5596 fn = build_cplus_new (TREE_TYPE (fn), fn);
5597 return convert_from_reference (fn);
5600 static GTY(()) tree java_iface_lookup_fn;
5602 /* Make an expression which yields the address of the Java interface
5603 method FN. This is achieved by generating a call to libjava's
5604 _Jv_LookupInterfaceMethodIdx(). */
5607 build_java_interface_fn_ref (tree fn, tree instance)
5609 tree lookup_fn, method, idx;
5610 tree klass_ref, iface, iface_ref;
5613 if (!java_iface_lookup_fn)
5615 tree endlink = build_void_list_node ();
5616 tree t = tree_cons (NULL_TREE, ptr_type_node,
5617 tree_cons (NULL_TREE, ptr_type_node,
5618 tree_cons (NULL_TREE, java_int_type_node,
5620 java_iface_lookup_fn
5621 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5622 build_function_type (ptr_type_node, t),
5623 0, NOT_BUILT_IN, NULL, NULL_TREE);
5626 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5627 This is the first entry in the vtable. */
5628 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5629 tf_warning_or_error),
5632 /* Get the java.lang.Class pointer for the interface being called. */
5633 iface = DECL_CONTEXT (fn);
5634 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5635 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5636 || DECL_CONTEXT (iface_ref) != iface)
5638 error ("could not find class$ field in java interface type %qT",
5640 return error_mark_node;
5642 iface_ref = build_address (iface_ref);
5643 iface_ref = convert (build_pointer_type (iface), iface_ref);
5645 /* Determine the itable index of FN. */
5647 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5649 if (!DECL_VIRTUAL_P (method))
5655 idx = build_int_cst (NULL_TREE, i);
5657 lookup_fn = build1 (ADDR_EXPR,
5658 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5659 java_iface_lookup_fn);
5660 return build_call_nary (ptr_type_node, lookup_fn,
5661 3, klass_ref, iface_ref, idx);
5664 /* Returns the value to use for the in-charge parameter when making a
5665 call to a function with the indicated NAME.
5667 FIXME:Can't we find a neater way to do this mapping? */
5670 in_charge_arg_for_name (tree name)
5672 if (name == base_ctor_identifier
5673 || name == base_dtor_identifier)
5674 return integer_zero_node;
5675 else if (name == complete_ctor_identifier)
5676 return integer_one_node;
5677 else if (name == complete_dtor_identifier)
5678 return integer_two_node;
5679 else if (name == deleting_dtor_identifier)
5680 return integer_three_node;
5682 /* This function should only be called with one of the names listed
5688 /* Build a call to a constructor, destructor, or an assignment
5689 operator for INSTANCE, an expression with class type. NAME
5690 indicates the special member function to call; ARGS are the
5691 arguments. BINFO indicates the base of INSTANCE that is to be
5692 passed as the `this' parameter to the member function called.
5694 FLAGS are the LOOKUP_* flags to use when processing the call.
5696 If NAME indicates a complete object constructor, INSTANCE may be
5697 NULL_TREE. In this case, the caller will call build_cplus_new to
5698 store the newly constructed object into a VAR_DECL. */
5701 build_special_member_call (tree instance, tree name, tree args,
5702 tree binfo, int flags, tsubst_flags_t complain)
5705 /* The type of the subobject to be constructed or destroyed. */
5708 gcc_assert (name == complete_ctor_identifier
5709 || name == base_ctor_identifier
5710 || name == complete_dtor_identifier
5711 || name == base_dtor_identifier
5712 || name == deleting_dtor_identifier
5713 || name == ansi_assopname (NOP_EXPR));
5716 /* Resolve the name. */
5717 if (!complete_type_or_else (binfo, NULL_TREE))
5718 return error_mark_node;
5720 binfo = TYPE_BINFO (binfo);
5723 gcc_assert (binfo != NULL_TREE);
5725 class_type = BINFO_TYPE (binfo);
5727 /* Handle the special case where INSTANCE is NULL_TREE. */
5728 if (name == complete_ctor_identifier && !instance)
5730 instance = build_int_cst (build_pointer_type (class_type), 0);
5731 instance = build1 (INDIRECT_REF, class_type, instance);
5735 if (name == complete_dtor_identifier
5736 || name == base_dtor_identifier
5737 || name == deleting_dtor_identifier)
5738 gcc_assert (args == NULL_TREE);
5740 /* Convert to the base class, if necessary. */
5741 if (!same_type_ignoring_top_level_qualifiers_p
5742 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5744 if (name != ansi_assopname (NOP_EXPR))
5745 /* For constructors and destructors, either the base is
5746 non-virtual, or it is virtual but we are doing the
5747 conversion from a constructor or destructor for the
5748 complete object. In either case, we can convert
5750 instance = convert_to_base_statically (instance, binfo);
5752 /* However, for assignment operators, we must convert
5753 dynamically if the base is virtual. */
5754 instance = build_base_path (PLUS_EXPR, instance,
5755 binfo, /*nonnull=*/1);
5759 gcc_assert (instance != NULL_TREE);
5761 fns = lookup_fnfields (binfo, name, 1);
5763 /* When making a call to a constructor or destructor for a subobject
5764 that uses virtual base classes, pass down a pointer to a VTT for
5766 if ((name == base_ctor_identifier
5767 || name == base_dtor_identifier)
5768 && CLASSTYPE_VBASECLASSES (class_type))
5773 /* If the current function is a complete object constructor
5774 or destructor, then we fetch the VTT directly.
5775 Otherwise, we look it up using the VTT we were given. */
5776 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5777 vtt = decay_conversion (vtt);
5778 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5779 build2 (EQ_EXPR, boolean_type_node,
5780 current_in_charge_parm, integer_zero_node),
5783 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5784 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5785 BINFO_SUBVTT_INDEX (binfo));
5787 args = tree_cons (NULL_TREE, sub_vtt, args);
5790 return build_new_method_call (instance, fns, args,
5791 TYPE_BINFO (BINFO_TYPE (binfo)),
5796 /* Return the NAME, as a C string. The NAME indicates a function that
5797 is a member of TYPE. *FREE_P is set to true if the caller must
5798 free the memory returned.
5800 Rather than go through all of this, we should simply set the names
5801 of constructors and destructors appropriately, and dispense with
5802 ctor_identifier, dtor_identifier, etc. */
5805 name_as_c_string (tree name, tree type, bool *free_p)
5809 /* Assume that we will not allocate memory. */
5811 /* Constructors and destructors are special. */
5812 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5815 = CONST_CAST (char *, IDENTIFIER_POINTER (constructor_name (type)));
5816 /* For a destructor, add the '~'. */
5817 if (name == complete_dtor_identifier
5818 || name == base_dtor_identifier
5819 || name == deleting_dtor_identifier)
5821 pretty_name = concat ("~", pretty_name, NULL);
5822 /* Remember that we need to free the memory allocated. */
5826 else if (IDENTIFIER_TYPENAME_P (name))
5828 pretty_name = concat ("operator ",
5829 type_as_string (TREE_TYPE (name),
5830 TFF_PLAIN_IDENTIFIER),
5832 /* Remember that we need to free the memory allocated. */
5836 pretty_name = CONST_CAST (char *, IDENTIFIER_POINTER (name));
5841 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
5842 be set, upon return, to the function called. */
5845 build_new_method_call (tree instance, tree fns, tree args,
5846 tree conversion_path, int flags,
5847 tree *fn_p, tsubst_flags_t complain)
5849 struct z_candidate *candidates = 0, *cand;
5850 tree explicit_targs = NULL_TREE;
5851 tree basetype = NULL_TREE;
5854 tree mem_args = NULL_TREE, instance_ptr;
5860 int template_only = 0;
5867 gcc_assert (instance != NULL_TREE);
5869 /* We don't know what function we're going to call, yet. */
5873 if (error_operand_p (instance)
5874 || error_operand_p (fns)
5875 || args == error_mark_node)
5876 return error_mark_node;
5878 if (!BASELINK_P (fns))
5880 if (complain & tf_error)
5881 error ("call to non-function %qD", fns);
5882 return error_mark_node;
5885 orig_instance = instance;
5889 /* Dismantle the baselink to collect all the information we need. */
5890 if (!conversion_path)
5891 conversion_path = BASELINK_BINFO (fns);
5892 access_binfo = BASELINK_ACCESS_BINFO (fns);
5893 optype = BASELINK_OPTYPE (fns);
5894 fns = BASELINK_FUNCTIONS (fns);
5895 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5897 explicit_targs = TREE_OPERAND (fns, 1);
5898 fns = TREE_OPERAND (fns, 0);
5901 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5902 || TREE_CODE (fns) == TEMPLATE_DECL
5903 || TREE_CODE (fns) == OVERLOAD);
5904 fn = get_first_fn (fns);
5905 name = DECL_NAME (fn);
5907 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5908 gcc_assert (CLASS_TYPE_P (basetype));
5910 if (processing_template_decl)
5912 instance = build_non_dependent_expr (instance);
5913 args = build_non_dependent_args (orig_args);
5916 /* The USER_ARGS are the arguments we will display to users if an
5917 error occurs. The USER_ARGS should not include any
5918 compiler-generated arguments. The "this" pointer hasn't been
5919 added yet. However, we must remove the VTT pointer if this is a
5920 call to a base-class constructor or destructor. */
5922 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5924 /* Callers should explicitly indicate whether they want to construct
5925 the complete object or just the part without virtual bases. */
5926 gcc_assert (name != ctor_identifier);
5927 /* Similarly for destructors. */
5928 gcc_assert (name != dtor_identifier);
5929 /* Remove the VTT pointer, if present. */
5930 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5931 && CLASSTYPE_VBASECLASSES (basetype))
5932 user_args = TREE_CHAIN (user_args);
5935 /* Process the argument list. */
5936 args = resolve_args (args);
5937 if (args == error_mark_node)
5938 return error_mark_node;
5940 instance_ptr = build_this (instance);
5942 /* It's OK to call destructors and constructors on cv-qualified objects.
5943 Therefore, convert the INSTANCE_PTR to the unqualified type, if
5945 if (DECL_DESTRUCTOR_P (fn)
5946 || DECL_CONSTRUCTOR_P (fn))
5948 tree type = build_pointer_type (basetype);
5949 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5950 instance_ptr = build_nop (type, instance_ptr);
5952 if (DECL_DESTRUCTOR_P (fn))
5953 name = complete_dtor_identifier;
5955 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
5956 initializer, not T({ }). If the type doesn't have a list ctor,
5957 break apart the list into separate ctor args. */
5958 if (DECL_CONSTRUCTOR_P (fn) && args
5959 && BRACE_ENCLOSED_INITIALIZER_P (TREE_VALUE (args))
5960 && CONSTRUCTOR_IS_DIRECT_INIT (TREE_VALUE (args))
5961 && !TYPE_HAS_LIST_CTOR (basetype))
5963 gcc_assert (TREE_CHAIN (args) == NULL_TREE);
5964 args = ctor_to_list (TREE_VALUE (args));
5967 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5968 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5970 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5971 p = conversion_obstack_alloc (0);
5973 for (fn = fns; fn; fn = OVL_NEXT (fn))
5975 tree t = OVL_CURRENT (fn);
5978 /* We can end up here for copy-init of same or base class. */
5979 if ((flags & LOOKUP_ONLYCONVERTING)
5980 && DECL_NONCONVERTING_P (t))
5983 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5984 this_arglist = mem_args;
5986 this_arglist = args;
5988 if (TREE_CODE (t) == TEMPLATE_DECL)
5989 /* A member template. */
5990 add_template_candidate (&candidates, t,
5993 this_arglist, optype,
5998 else if (! template_only)
5999 add_function_candidate (&candidates, t,
6007 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6010 if (complain & tf_error)
6012 if (!COMPLETE_TYPE_P (basetype))
6013 cxx_incomplete_type_error (instance_ptr, basetype);
6019 pretty_name = name_as_c_string (name, basetype, &free_p);
6020 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6021 basetype, pretty_name, user_args,
6022 TREE_TYPE (TREE_TYPE (instance_ptr)));
6026 print_z_candidates (candidates);
6028 call = error_mark_node;
6032 cand = tourney (candidates);
6038 if (complain & tf_error)
6040 pretty_name = name_as_c_string (name, basetype, &free_p);
6041 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6043 print_z_candidates (candidates);
6047 call = error_mark_node;
6053 if (!(flags & LOOKUP_NONVIRTUAL)
6054 && DECL_PURE_VIRTUAL_P (fn)
6055 && instance == current_class_ref
6056 && (DECL_CONSTRUCTOR_P (current_function_decl)
6057 || DECL_DESTRUCTOR_P (current_function_decl))
6058 && (complain & tf_warning))
6059 /* This is not an error, it is runtime undefined
6061 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6062 "abstract virtual %q#D called from constructor"
6063 : "abstract virtual %q#D called from destructor"),
6066 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6067 && is_dummy_object (instance_ptr))
6069 if (complain & tf_error)
6070 error ("cannot call member function %qD without object",
6072 call = error_mark_node;
6076 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6077 && resolves_to_fixed_type_p (instance, 0))
6078 flags |= LOOKUP_NONVIRTUAL;
6079 /* Now we know what function is being called. */
6082 /* Build the actual CALL_EXPR. */
6083 call = build_over_call (cand, flags, complain);
6084 /* In an expression of the form `a->f()' where `f' turns
6085 out to be a static member function, `a' is
6086 none-the-less evaluated. */
6087 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6088 && !is_dummy_object (instance_ptr)
6089 && TREE_SIDE_EFFECTS (instance_ptr))
6090 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6091 instance_ptr, call);
6092 else if (call != error_mark_node
6093 && DECL_DESTRUCTOR_P (cand->fn)
6094 && !VOID_TYPE_P (TREE_TYPE (call)))
6095 /* An explicit call of the form "x->~X()" has type
6096 "void". However, on platforms where destructors
6097 return "this" (i.e., those where
6098 targetm.cxx.cdtor_returns_this is true), such calls
6099 will appear to have a return value of pointer type
6100 to the low-level call machinery. We do not want to
6101 change the low-level machinery, since we want to be
6102 able to optimize "delete f()" on such platforms as
6103 "operator delete(~X(f()))" (rather than generating
6104 "t = f(), ~X(t), operator delete (t)"). */
6105 call = build_nop (void_type_node, call);
6110 if (processing_template_decl && call != error_mark_node)
6112 bool cast_to_void = false;
6114 if (TREE_CODE (call) == COMPOUND_EXPR)
6115 call = TREE_OPERAND (call, 1);
6116 else if (TREE_CODE (call) == NOP_EXPR)
6118 cast_to_void = true;
6119 call = TREE_OPERAND (call, 0);
6121 if (TREE_CODE (call) == INDIRECT_REF)
6122 call = TREE_OPERAND (call, 0);
6123 call = (build_min_non_dep_call_list
6125 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6126 orig_instance, orig_fns, NULL_TREE),
6128 call = convert_from_reference (call);
6130 call = build_nop (void_type_node, call);
6133 /* Free all the conversions we allocated. */
6134 obstack_free (&conversion_obstack, p);
6139 /* Returns true iff standard conversion sequence ICS1 is a proper
6140 subsequence of ICS2. */
6143 is_subseq (conversion *ics1, conversion *ics2)
6145 /* We can assume that a conversion of the same code
6146 between the same types indicates a subsequence since we only get
6147 here if the types we are converting from are the same. */
6149 while (ics1->kind == ck_rvalue
6150 || ics1->kind == ck_lvalue)
6151 ics1 = ics1->u.next;
6155 while (ics2->kind == ck_rvalue
6156 || ics2->kind == ck_lvalue)
6157 ics2 = ics2->u.next;
6159 if (ics2->kind == ck_user
6160 || ics2->kind == ck_ambig
6161 || ics2->kind == ck_identity)
6162 /* At this point, ICS1 cannot be a proper subsequence of
6163 ICS2. We can get a USER_CONV when we are comparing the
6164 second standard conversion sequence of two user conversion
6168 ics2 = ics2->u.next;
6170 if (ics2->kind == ics1->kind
6171 && same_type_p (ics2->type, ics1->type)
6172 && same_type_p (ics2->u.next->type,
6173 ics1->u.next->type))
6178 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6179 be any _TYPE nodes. */
6182 is_properly_derived_from (tree derived, tree base)
6184 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6187 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6188 considers every class derived from itself. */
6189 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6190 && DERIVED_FROM_P (base, derived));
6193 /* We build the ICS for an implicit object parameter as a pointer
6194 conversion sequence. However, such a sequence should be compared
6195 as if it were a reference conversion sequence. If ICS is the
6196 implicit conversion sequence for an implicit object parameter,
6197 modify it accordingly. */
6200 maybe_handle_implicit_object (conversion **ics)
6204 /* [over.match.funcs]
6206 For non-static member functions, the type of the
6207 implicit object parameter is "reference to cv X"
6208 where X is the class of which the function is a
6209 member and cv is the cv-qualification on the member
6210 function declaration. */
6211 conversion *t = *ics;
6212 tree reference_type;
6214 /* The `this' parameter is a pointer to a class type. Make the
6215 implicit conversion talk about a reference to that same class
6217 reference_type = TREE_TYPE (t->type);
6218 reference_type = build_reference_type (reference_type);
6220 if (t->kind == ck_qual)
6222 if (t->kind == ck_ptr)
6224 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6225 t = direct_reference_binding (reference_type, t);
6227 t->rvaluedness_matches_p = 0;
6232 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6233 and return the initial reference binding conversion. Otherwise,
6234 leave *ICS unchanged and return NULL. */
6237 maybe_handle_ref_bind (conversion **ics)
6239 if ((*ics)->kind == ck_ref_bind)
6241 conversion *old_ics = *ics;
6242 *ics = old_ics->u.next;
6243 (*ics)->user_conv_p = old_ics->user_conv_p;
6244 (*ics)->bad_p = old_ics->bad_p;
6251 /* Compare two implicit conversion sequences according to the rules set out in
6252 [over.ics.rank]. Return values:
6254 1: ics1 is better than ics2
6255 -1: ics2 is better than ics1
6256 0: ics1 and ics2 are indistinguishable */
6259 compare_ics (conversion *ics1, conversion *ics2)
6265 tree deref_from_type1 = NULL_TREE;
6266 tree deref_from_type2 = NULL_TREE;
6267 tree deref_to_type1 = NULL_TREE;
6268 tree deref_to_type2 = NULL_TREE;
6269 conversion_rank rank1, rank2;
6271 /* REF_BINDING is nonzero if the result of the conversion sequence
6272 is a reference type. In that case REF_CONV is the reference
6273 binding conversion. */
6274 conversion *ref_conv1;
6275 conversion *ref_conv2;
6277 /* Handle implicit object parameters. */
6278 maybe_handle_implicit_object (&ics1);
6279 maybe_handle_implicit_object (&ics2);
6281 /* Handle reference parameters. */
6282 ref_conv1 = maybe_handle_ref_bind (&ics1);
6283 ref_conv2 = maybe_handle_ref_bind (&ics2);
6285 /* List-initialization sequence L1 is a better conversion sequence than
6286 list-initialization sequence L2 if L1 converts to
6287 std::initializer_list<X> for some X and L2 does not. */
6288 if (ics1->kind == ck_list && ics2->kind != ck_list)
6290 if (ics2->kind == ck_list && ics1->kind != ck_list)
6295 When comparing the basic forms of implicit conversion sequences (as
6296 defined in _over.best.ics_)
6298 --a standard conversion sequence (_over.ics.scs_) is a better
6299 conversion sequence than a user-defined conversion sequence
6300 or an ellipsis conversion sequence, and
6302 --a user-defined conversion sequence (_over.ics.user_) is a
6303 better conversion sequence than an ellipsis conversion sequence
6304 (_over.ics.ellipsis_). */
6305 rank1 = CONVERSION_RANK (ics1);
6306 rank2 = CONVERSION_RANK (ics2);
6310 else if (rank1 < rank2)
6313 if (rank1 == cr_bad)
6315 /* XXX Isn't this an extension? */
6316 /* Both ICS are bad. We try to make a decision based on what
6317 would have happened if they'd been good. */
6318 if (ics1->user_conv_p > ics2->user_conv_p
6319 || ics1->rank > ics2->rank)
6321 else if (ics1->user_conv_p < ics2->user_conv_p
6322 || ics1->rank < ics2->rank)
6325 /* We couldn't make up our minds; try to figure it out below. */
6328 if (ics1->ellipsis_p || ics1->kind == ck_list)
6329 /* Both conversions are ellipsis conversions or both are building a
6330 std::initializer_list. */
6333 /* User-defined conversion sequence U1 is a better conversion sequence
6334 than another user-defined conversion sequence U2 if they contain the
6335 same user-defined conversion operator or constructor and if the sec-
6336 ond standard conversion sequence of U1 is better than the second
6337 standard conversion sequence of U2. */
6339 if (ics1->user_conv_p)
6344 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6345 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6347 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6348 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6351 if (t1->cand->fn != t2->cand->fn)
6354 /* We can just fall through here, after setting up
6355 FROM_TYPE1 and FROM_TYPE2. */
6356 from_type1 = t1->type;
6357 from_type2 = t2->type;
6364 /* We're dealing with two standard conversion sequences.
6368 Standard conversion sequence S1 is a better conversion
6369 sequence than standard conversion sequence S2 if
6371 --S1 is a proper subsequence of S2 (comparing the conversion
6372 sequences in the canonical form defined by _over.ics.scs_,
6373 excluding any Lvalue Transformation; the identity
6374 conversion sequence is considered to be a subsequence of
6375 any non-identity conversion sequence */
6378 while (t1->kind != ck_identity)
6380 from_type1 = t1->type;
6383 while (t2->kind != ck_identity)
6385 from_type2 = t2->type;
6388 /* One sequence can only be a subsequence of the other if they start with
6389 the same type. They can start with different types when comparing the
6390 second standard conversion sequence in two user-defined conversion
6392 if (same_type_p (from_type1, from_type2))
6394 if (is_subseq (ics1, ics2))
6396 if (is_subseq (ics2, ics1))
6404 --the rank of S1 is better than the rank of S2 (by the rules
6407 Standard conversion sequences are ordered by their ranks: an Exact
6408 Match is a better conversion than a Promotion, which is a better
6409 conversion than a Conversion.
6411 Two conversion sequences with the same rank are indistinguishable
6412 unless one of the following rules applies:
6414 --A conversion that is not a conversion of a pointer, or pointer
6415 to member, to bool is better than another conversion that is such
6418 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6419 so that we do not have to check it explicitly. */
6420 if (ics1->rank < ics2->rank)
6422 else if (ics2->rank < ics1->rank)
6425 to_type1 = ics1->type;
6426 to_type2 = ics2->type;
6428 /* A conversion from scalar arithmetic type to complex is worse than a
6429 conversion between scalar arithmetic types. */
6430 if (same_type_p (from_type1, from_type2)
6431 && ARITHMETIC_TYPE_P (from_type1)
6432 && ARITHMETIC_TYPE_P (to_type1)
6433 && ARITHMETIC_TYPE_P (to_type2)
6434 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6435 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6437 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6443 if (TYPE_PTR_P (from_type1)
6444 && TYPE_PTR_P (from_type2)
6445 && TYPE_PTR_P (to_type1)
6446 && TYPE_PTR_P (to_type2))
6448 deref_from_type1 = TREE_TYPE (from_type1);
6449 deref_from_type2 = TREE_TYPE (from_type2);
6450 deref_to_type1 = TREE_TYPE (to_type1);
6451 deref_to_type2 = TREE_TYPE (to_type2);
6453 /* The rules for pointers to members A::* are just like the rules
6454 for pointers A*, except opposite: if B is derived from A then
6455 A::* converts to B::*, not vice versa. For that reason, we
6456 switch the from_ and to_ variables here. */
6457 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6458 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6459 || (TYPE_PTRMEMFUNC_P (from_type1)
6460 && TYPE_PTRMEMFUNC_P (from_type2)
6461 && TYPE_PTRMEMFUNC_P (to_type1)
6462 && TYPE_PTRMEMFUNC_P (to_type2)))
6464 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6465 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6466 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6467 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6470 if (deref_from_type1 != NULL_TREE
6471 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6472 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6474 /* This was one of the pointer or pointer-like conversions.
6478 --If class B is derived directly or indirectly from class A,
6479 conversion of B* to A* is better than conversion of B* to
6480 void*, and conversion of A* to void* is better than
6481 conversion of B* to void*. */
6482 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6483 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6485 if (is_properly_derived_from (deref_from_type1,
6488 else if (is_properly_derived_from (deref_from_type2,
6492 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6493 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6495 if (same_type_p (deref_from_type1, deref_from_type2))
6497 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6499 if (is_properly_derived_from (deref_from_type1,
6503 /* We know that DEREF_TO_TYPE1 is `void' here. */
6504 else if (is_properly_derived_from (deref_from_type1,
6509 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6510 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6514 --If class B is derived directly or indirectly from class A
6515 and class C is derived directly or indirectly from B,
6517 --conversion of C* to B* is better than conversion of C* to
6520 --conversion of B* to A* is better than conversion of C* to
6522 if (same_type_p (deref_from_type1, deref_from_type2))
6524 if (is_properly_derived_from (deref_to_type1,
6527 else if (is_properly_derived_from (deref_to_type2,
6531 else if (same_type_p (deref_to_type1, deref_to_type2))
6533 if (is_properly_derived_from (deref_from_type2,
6536 else if (is_properly_derived_from (deref_from_type1,
6542 else if (CLASS_TYPE_P (non_reference (from_type1))
6543 && same_type_p (from_type1, from_type2))
6545 tree from = non_reference (from_type1);
6549 --binding of an expression of type C to a reference of type
6550 B& is better than binding an expression of type C to a
6551 reference of type A&
6553 --conversion of C to B is better than conversion of C to A, */
6554 if (is_properly_derived_from (from, to_type1)
6555 && is_properly_derived_from (from, to_type2))
6557 if (is_properly_derived_from (to_type1, to_type2))
6559 else if (is_properly_derived_from (to_type2, to_type1))
6563 else if (CLASS_TYPE_P (non_reference (to_type1))
6564 && same_type_p (to_type1, to_type2))
6566 tree to = non_reference (to_type1);
6570 --binding of an expression of type B to a reference of type
6571 A& is better than binding an expression of type C to a
6572 reference of type A&,
6574 --conversion of B to A is better than conversion of C to A */
6575 if (is_properly_derived_from (from_type1, to)
6576 && is_properly_derived_from (from_type2, to))
6578 if (is_properly_derived_from (from_type2, from_type1))
6580 else if (is_properly_derived_from (from_type1, from_type2))
6587 --S1 and S2 differ only in their qualification conversion and yield
6588 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6589 qualification signature of type T1 is a proper subset of the cv-
6590 qualification signature of type T2 */
6591 if (ics1->kind == ck_qual
6592 && ics2->kind == ck_qual
6593 && same_type_p (from_type1, from_type2))
6595 int result = comp_cv_qual_signature (to_type1, to_type2);
6602 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6603 to an implicit object parameter, and either S1 binds an lvalue reference
6604 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6605 reference to an rvalue and S2 binds an lvalue reference
6606 (C++0x draft standard, 13.3.3.2)
6608 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6609 types to which the references refer are the same type except for
6610 top-level cv-qualifiers, and the type to which the reference
6611 initialized by S2 refers is more cv-qualified than the type to
6612 which the reference initialized by S1 refers */
6614 if (ref_conv1 && ref_conv2)
6616 if (!ref_conv1->this_p && !ref_conv2->this_p
6617 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6618 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6620 if (ref_conv1->rvaluedness_matches_p)
6622 if (ref_conv2->rvaluedness_matches_p)
6626 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6627 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6628 TREE_TYPE (ref_conv1->type));
6631 /* Neither conversion sequence is better than the other. */
6635 /* The source type for this standard conversion sequence. */
6638 source_type (conversion *t)
6640 for (;; t = t->u.next)
6642 if (t->kind == ck_user
6643 || t->kind == ck_ambig
6644 || t->kind == ck_identity)
6650 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6651 a pointer to LOSER and re-running joust to produce the warning if WINNER
6652 is actually used. */
6655 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6657 candidate_warning *cw = (candidate_warning *)
6658 conversion_obstack_alloc (sizeof (candidate_warning));
6660 cw->next = winner->warnings;
6661 winner->warnings = cw;
6664 /* Compare two candidates for overloading as described in
6665 [over.match.best]. Return values:
6667 1: cand1 is better than cand2
6668 -1: cand2 is better than cand1
6669 0: cand1 and cand2 are indistinguishable */
6672 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6675 int off1 = 0, off2 = 0;
6679 /* Candidates that involve bad conversions are always worse than those
6681 if (cand1->viable > cand2->viable)
6683 if (cand1->viable < cand2->viable)
6686 /* If we have two pseudo-candidates for conversions to the same type,
6687 or two candidates for the same function, arbitrarily pick one. */
6688 if (cand1->fn == cand2->fn
6689 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6692 /* a viable function F1
6693 is defined to be a better function than another viable function F2 if
6694 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6695 ICSi(F2), and then */
6697 /* for some argument j, ICSj(F1) is a better conversion sequence than
6700 /* For comparing static and non-static member functions, we ignore
6701 the implicit object parameter of the non-static function. The
6702 standard says to pretend that the static function has an object
6703 parm, but that won't work with operator overloading. */
6704 len = cand1->num_convs;
6705 if (len != cand2->num_convs)
6707 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6708 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6710 gcc_assert (static_1 != static_2);
6721 for (i = 0; i < len; ++i)
6723 conversion *t1 = cand1->convs[i + off1];
6724 conversion *t2 = cand2->convs[i + off2];
6725 int comp = compare_ics (t1, t2);
6730 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6731 == cr_std + cr_promotion)
6732 && t1->kind == ck_std
6733 && t2->kind == ck_std
6734 && TREE_CODE (t1->type) == INTEGER_TYPE
6735 && TREE_CODE (t2->type) == INTEGER_TYPE
6736 && (TYPE_PRECISION (t1->type)
6737 == TYPE_PRECISION (t2->type))
6738 && (TYPE_UNSIGNED (t1->u.next->type)
6739 || (TREE_CODE (t1->u.next->type)
6742 tree type = t1->u.next->type;
6744 struct z_candidate *w, *l;
6746 type1 = t1->type, type2 = t2->type,
6747 w = cand1, l = cand2;
6749 type1 = t2->type, type2 = t1->type,
6750 w = cand2, l = cand1;
6754 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6755 type, type1, type2);
6756 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6762 if (winner && comp != winner)
6771 /* warn about confusing overload resolution for user-defined conversions,
6772 either between a constructor and a conversion op, or between two
6774 if (winner && warn_conversion && cand1->second_conv
6775 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6776 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6778 struct z_candidate *w, *l;
6779 bool give_warning = false;
6782 w = cand1, l = cand2;
6784 w = cand2, l = cand1;
6786 /* We don't want to complain about `X::operator T1 ()'
6787 beating `X::operator T2 () const', when T2 is a no less
6788 cv-qualified version of T1. */
6789 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6790 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6792 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6793 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6795 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6800 if (!comp_ptr_ttypes (t, f))
6801 give_warning = true;
6804 give_warning = true;
6810 tree source = source_type (w->convs[0]);
6811 if (! DECL_CONSTRUCTOR_P (w->fn))
6812 source = TREE_TYPE (source);
6813 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
6814 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
6815 source, w->second_conv->type))
6817 inform (input_location, " because conversion sequence for the argument is better");
6828 F1 is a non-template function and F2 is a template function
6831 if (!cand1->template_decl && cand2->template_decl)
6833 else if (cand1->template_decl && !cand2->template_decl)
6837 F1 and F2 are template functions and the function template for F1 is
6838 more specialized than the template for F2 according to the partial
6841 if (cand1->template_decl && cand2->template_decl)
6843 winner = more_specialized_fn
6844 (TI_TEMPLATE (cand1->template_decl),
6845 TI_TEMPLATE (cand2->template_decl),
6846 /* [temp.func.order]: The presence of unused ellipsis and default
6847 arguments has no effect on the partial ordering of function
6848 templates. add_function_candidate() will not have
6849 counted the "this" argument for constructors. */
6850 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6856 the context is an initialization by user-defined conversion (see
6857 _dcl.init_ and _over.match.user_) and the standard conversion
6858 sequence from the return type of F1 to the destination type (i.e.,
6859 the type of the entity being initialized) is a better conversion
6860 sequence than the standard conversion sequence from the return type
6861 of F2 to the destination type. */
6863 if (cand1->second_conv)
6865 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6870 /* Check whether we can discard a builtin candidate, either because we
6871 have two identical ones or matching builtin and non-builtin candidates.
6873 (Pedantically in the latter case the builtin which matched the user
6874 function should not be added to the overload set, but we spot it here.
6877 ... the builtin candidates include ...
6878 - do not have the same parameter type list as any non-template
6879 non-member candidate. */
6881 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6882 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6884 for (i = 0; i < len; ++i)
6885 if (!same_type_p (cand1->convs[i]->type,
6886 cand2->convs[i]->type))
6888 if (i == cand1->num_convs)
6890 if (cand1->fn == cand2->fn)
6891 /* Two built-in candidates; arbitrarily pick one. */
6893 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6894 /* cand1 is built-in; prefer cand2. */
6897 /* cand2 is built-in; prefer cand1. */
6902 /* If the two function declarations represent the same function (this can
6903 happen with declarations in multiple scopes and arg-dependent lookup),
6904 arbitrarily choose one. But first make sure the default args we're
6906 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6907 && equal_functions (cand1->fn, cand2->fn))
6909 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
6910 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
6912 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
6914 for (i = 0; i < len; ++i)
6916 /* Don't crash if the fn is variadic. */
6919 parms1 = TREE_CHAIN (parms1);
6920 parms2 = TREE_CHAIN (parms2);
6924 parms1 = TREE_CHAIN (parms1);
6926 parms2 = TREE_CHAIN (parms2);
6930 if (!cp_tree_equal (TREE_PURPOSE (parms1),
6931 TREE_PURPOSE (parms2)))
6935 permerror (input_location, "default argument mismatch in "
6936 "overload resolution");
6937 inform (input_location,
6938 " candidate 1: %q+#F", cand1->fn);
6939 inform (input_location,
6940 " candidate 2: %q+#F", cand2->fn);
6943 add_warning (cand1, cand2);
6946 parms1 = TREE_CHAIN (parms1);
6947 parms2 = TREE_CHAIN (parms2);
6955 /* Extension: If the worst conversion for one candidate is worse than the
6956 worst conversion for the other, take the first. */
6959 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6960 struct z_candidate *w = 0, *l = 0;
6962 for (i = 0; i < len; ++i)
6964 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6965 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6966 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6967 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6970 winner = 1, w = cand1, l = cand2;
6972 winner = -1, w = cand2, l = cand1;
6977 pedwarn (input_location, 0,
6978 "ISO C++ says that these are ambiguous, even "
6979 "though the worst conversion for the first is better than "
6980 "the worst conversion for the second:");
6981 print_z_candidate (_("candidate 1:"), w);
6982 print_z_candidate (_("candidate 2:"), l);
6990 gcc_assert (!winner);
6994 /* Given a list of candidates for overloading, find the best one, if any.
6995 This algorithm has a worst case of O(2n) (winner is last), and a best
6996 case of O(n/2) (totally ambiguous); much better than a sorting
6999 static struct z_candidate *
7000 tourney (struct z_candidate *candidates)
7002 struct z_candidate *champ = candidates, *challenger;
7004 int champ_compared_to_predecessor = 0;
7006 /* Walk through the list once, comparing each current champ to the next
7007 candidate, knocking out a candidate or two with each comparison. */
7009 for (challenger = champ->next; challenger; )
7011 fate = joust (champ, challenger, 0);
7013 challenger = challenger->next;
7018 champ = challenger->next;
7021 champ_compared_to_predecessor = 0;
7026 champ_compared_to_predecessor = 1;
7029 challenger = champ->next;
7033 /* Make sure the champ is better than all the candidates it hasn't yet
7034 been compared to. */
7036 for (challenger = candidates;
7038 && !(champ_compared_to_predecessor && challenger->next == champ);
7039 challenger = challenger->next)
7041 fate = joust (champ, challenger, 0);
7049 /* Returns nonzero if things of type FROM can be converted to TO. */
7052 can_convert (tree to, tree from)
7054 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
7057 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7060 can_convert_arg (tree to, tree from, tree arg, int flags)
7066 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7067 p = conversion_obstack_alloc (0);
7069 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7071 ok_p = (t && !t->bad_p);
7073 /* Free all the conversions we allocated. */
7074 obstack_free (&conversion_obstack, p);
7079 /* Like can_convert_arg, but allows dubious conversions as well. */
7082 can_convert_arg_bad (tree to, tree from, tree arg)
7087 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7088 p = conversion_obstack_alloc (0);
7089 /* Try to perform the conversion. */
7090 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7092 /* Free all the conversions we allocated. */
7093 obstack_free (&conversion_obstack, p);
7098 /* Convert EXPR to TYPE. Return the converted expression.
7100 Note that we allow bad conversions here because by the time we get to
7101 this point we are committed to doing the conversion. If we end up
7102 doing a bad conversion, convert_like will complain. */
7105 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7110 if (error_operand_p (expr))
7111 return error_mark_node;
7113 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7114 p = conversion_obstack_alloc (0);
7116 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7121 if (complain & tf_error)
7122 error ("could not convert %qE to %qT", expr, type);
7123 expr = error_mark_node;
7125 else if (processing_template_decl)
7127 /* In a template, we are only concerned about determining the
7128 type of non-dependent expressions, so we do not have to
7129 perform the actual conversion. */
7130 if (TREE_TYPE (expr) != type)
7131 expr = build_nop (type, expr);
7134 expr = convert_like (conv, expr, complain);
7136 /* Free all the conversions we allocated. */
7137 obstack_free (&conversion_obstack, p);
7142 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7143 permitted. If the conversion is valid, the converted expression is
7144 returned. Otherwise, NULL_TREE is returned, except in the case
7145 that TYPE is a class type; in that case, an error is issued. If
7146 C_CAST_P is true, then this direction initialization is taking
7147 place as part of a static_cast being attempted as part of a C-style
7151 perform_direct_initialization_if_possible (tree type,
7154 tsubst_flags_t complain)
7159 if (type == error_mark_node || error_operand_p (expr))
7160 return error_mark_node;
7163 If the destination type is a (possibly cv-qualified) class type:
7165 -- If the initialization is direct-initialization ...,
7166 constructors are considered. ... If no constructor applies, or
7167 the overload resolution is ambiguous, the initialization is
7169 if (CLASS_TYPE_P (type))
7171 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7172 build_tree_list (NULL_TREE, expr),
7173 type, LOOKUP_NORMAL, complain);
7174 return build_cplus_new (type, expr);
7177 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7178 p = conversion_obstack_alloc (0);
7180 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7183 if (!conv || conv->bad_p)
7186 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7187 /*issue_conversion_warnings=*/false,
7189 tf_warning_or_error);
7191 /* Free all the conversions we allocated. */
7192 obstack_free (&conversion_obstack, p);
7197 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7198 is being bound to a temporary. Create and return a new VAR_DECL
7199 with the indicated TYPE; this variable will store the value to
7200 which the reference is bound. */
7203 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7207 /* Create the variable. */
7208 var = create_temporary_var (type);
7210 /* Register the variable. */
7211 if (TREE_STATIC (decl))
7213 /* Namespace-scope or local static; give it a mangled name. */
7216 TREE_STATIC (var) = 1;
7217 name = mangle_ref_init_variable (decl);
7218 DECL_NAME (var) = name;
7219 SET_DECL_ASSEMBLER_NAME (var, name);
7220 var = pushdecl_top_level (var);
7223 /* Create a new cleanup level if necessary. */
7224 maybe_push_cleanup_level (type);
7229 /* EXPR is the initializer for a variable DECL of reference or
7230 std::initializer_list type. Create, push and return a new VAR_DECL
7231 for the initializer so that it will live as long as DECL. Any
7232 cleanup for the new variable is returned through CLEANUP, and the
7233 code to initialize the new variable is returned through INITP. */
7236 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7242 /* Create the temporary variable. */
7243 type = TREE_TYPE (expr);
7244 var = make_temporary_var_for_ref_to_temp (decl, type);
7245 layout_decl (var, 0);
7246 /* If the rvalue is the result of a function call it will be
7247 a TARGET_EXPR. If it is some other construct (such as a
7248 member access expression where the underlying object is
7249 itself the result of a function call), turn it into a
7250 TARGET_EXPR here. It is important that EXPR be a
7251 TARGET_EXPR below since otherwise the INIT_EXPR will
7252 attempt to make a bitwise copy of EXPR to initialize
7254 if (TREE_CODE (expr) != TARGET_EXPR)
7255 expr = get_target_expr (expr);
7256 /* Create the INIT_EXPR that will initialize the temporary
7258 init = build2 (INIT_EXPR, type, var, expr);
7259 if (at_function_scope_p ())
7261 add_decl_expr (var);
7263 if (TREE_STATIC (var))
7264 init = add_stmt_to_compound (init, register_dtor_fn (var));
7266 *cleanup = cxx_maybe_build_cleanup (var);
7268 /* We must be careful to destroy the temporary only
7269 after its initialization has taken place. If the
7270 initialization throws an exception, then the
7271 destructor should not be run. We cannot simply
7272 transform INIT into something like:
7274 (INIT, ({ CLEANUP_STMT; }))
7276 because emit_local_var always treats the
7277 initializer as a full-expression. Thus, the
7278 destructor would run too early; it would run at the
7279 end of initializing the reference variable, rather
7280 than at the end of the block enclosing the
7283 The solution is to pass back a cleanup expression
7284 which the caller is responsible for attaching to
7285 the statement tree. */
7289 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7290 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7291 static_aggregates = tree_cons (NULL_TREE, var,
7299 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7300 initializing a variable of that TYPE. If DECL is non-NULL, it is
7301 the VAR_DECL being initialized with the EXPR. (In that case, the
7302 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7303 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7304 return, if *CLEANUP is no longer NULL, it will be an expression
7305 that should be pushed as a cleanup after the returned expression
7306 is used to initialize DECL.
7308 Return the converted expression. */
7311 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7316 if (type == error_mark_node || error_operand_p (expr))
7317 return error_mark_node;
7319 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7320 p = conversion_obstack_alloc (0);
7322 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7324 if (!conv || conv->bad_p)
7326 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7327 && !TYPE_REF_IS_RVALUE (type)
7328 && !real_lvalue_p (expr))
7329 error ("invalid initialization of non-const reference of "
7330 "type %qT from a temporary of type %qT",
7331 type, TREE_TYPE (expr));
7333 error ("invalid initialization of reference of type "
7334 "%qT from expression of type %qT", type,
7336 return error_mark_node;
7339 /* If DECL is non-NULL, then this special rule applies:
7343 The temporary to which the reference is bound or the temporary
7344 that is the complete object to which the reference is bound
7345 persists for the lifetime of the reference.
7347 The temporaries created during the evaluation of the expression
7348 initializing the reference, except the temporary to which the
7349 reference is bound, are destroyed at the end of the
7350 full-expression in which they are created.
7352 In that case, we store the converted expression into a new
7353 VAR_DECL in a new scope.
7355 However, we want to be careful not to create temporaries when
7356 they are not required. For example, given:
7359 struct D : public B {};
7363 there is no need to copy the return value from "f"; we can just
7364 extend its lifetime. Similarly, given:
7367 struct T { operator S(); };
7371 we can extend the lifetime of the return value of the conversion
7373 gcc_assert (conv->kind == ck_ref_bind);
7377 tree base_conv_type;
7379 /* Skip over the REF_BIND. */
7380 conv = conv->u.next;
7381 /* If the next conversion is a BASE_CONV, skip that too -- but
7382 remember that the conversion was required. */
7383 if (conv->kind == ck_base)
7385 base_conv_type = conv->type;
7386 conv = conv->u.next;
7389 base_conv_type = NULL_TREE;
7390 /* Perform the remainder of the conversion. */
7391 expr = convert_like_real (conv, expr,
7392 /*fn=*/NULL_TREE, /*argnum=*/0,
7394 /*issue_conversion_warnings=*/true,
7396 tf_warning_or_error);
7397 if (error_operand_p (expr))
7398 expr = error_mark_node;
7401 if (!lvalue_or_rvalue_with_address_p (expr))
7404 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7405 /* Use its address to initialize the reference variable. */
7406 expr = build_address (var);
7408 expr = convert_to_base (expr,
7409 build_pointer_type (base_conv_type),
7410 /*check_access=*/true,
7412 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7415 /* Take the address of EXPR. */
7416 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7417 /* If a BASE_CONV was required, perform it now. */
7419 expr = (perform_implicit_conversion
7420 (build_pointer_type (base_conv_type), expr,
7421 tf_warning_or_error));
7422 expr = build_nop (type, expr);
7426 /* Perform the conversion. */
7427 expr = convert_like (conv, expr, tf_warning_or_error);
7429 /* Free all the conversions we allocated. */
7430 obstack_free (&conversion_obstack, p);
7435 /* Returns true iff TYPE is some variant of std::initializer_list. */
7438 is_std_init_list (tree type)
7440 return (CLASS_TYPE_P (type)
7441 && CP_TYPE_CONTEXT (type) == std_node
7442 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7445 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7446 will accept an argument list of a single std::initializer_list<T>. */
7449 is_list_ctor (tree decl)
7451 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7454 if (!args || args == void_list_node)
7457 arg = non_reference (TREE_VALUE (args));
7458 if (!is_std_init_list (arg))
7461 args = TREE_CHAIN (args);
7463 if (args && args != void_list_node && !TREE_PURPOSE (args))
7464 /* There are more non-defaulted parms. */
7470 #include "gt-cp-call.h"