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 VEC(tree,gc) *resolve_args (VEC(tree,gc) *);
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, const VEC(tree,gc) *,
157 tree, tree, tree, int, unification_kind_t);
158 static struct z_candidate *add_template_candidate_real
159 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
160 tree, tree, tree, int, tree, unification_kind_t);
161 static struct z_candidate *add_template_conv_candidate
162 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
164 static void add_builtin_candidates
165 (struct z_candidate **, enum tree_code, enum tree_code,
167 static void add_builtin_candidate
168 (struct z_candidate **, enum tree_code, enum tree_code,
169 tree, tree, tree, tree *, tree *, int);
170 static bool is_complete (tree);
171 static void build_builtin_candidate
172 (struct z_candidate **, tree, tree, tree, tree *, tree *,
174 static struct z_candidate *add_conv_candidate
175 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
177 static struct z_candidate *add_function_candidate
178 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
180 static conversion *implicit_conversion (tree, tree, tree, bool, int);
181 static conversion *standard_conversion (tree, tree, tree, bool, int);
182 static conversion *reference_binding (tree, tree, tree, bool, int);
183 static conversion *build_conv (conversion_kind, tree, conversion *);
184 static conversion *build_list_conv (tree, tree, int);
185 static bool is_subseq (conversion *, conversion *);
186 static conversion *maybe_handle_ref_bind (conversion **);
187 static void maybe_handle_implicit_object (conversion **);
188 static struct z_candidate *add_candidate
189 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
190 conversion **, tree, tree, int);
191 static tree source_type (conversion *);
192 static void add_warning (struct z_candidate *, struct z_candidate *);
193 static bool reference_compatible_p (tree, tree);
194 static conversion *convert_class_to_reference (tree, tree, tree, int);
195 static conversion *direct_reference_binding (tree, conversion *);
196 static bool promoted_arithmetic_type_p (tree);
197 static conversion *conditional_conversion (tree, tree);
198 static char *name_as_c_string (tree, tree, bool *);
199 static tree prep_operand (tree);
200 static void add_candidates (tree, const VEC(tree,gc) *, tree, bool, tree, tree,
201 int, struct z_candidate **);
202 static conversion *merge_conversion_sequences (conversion *, conversion *);
203 static bool magic_varargs_p (tree);
204 static tree build_temp (tree, tree, int, diagnostic_t *);
206 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
207 NAME can take many forms... */
210 check_dtor_name (tree basetype, tree name)
212 /* Just accept something we've already complained about. */
213 if (name == error_mark_node)
216 if (TREE_CODE (name) == TYPE_DECL)
217 name = TREE_TYPE (name);
218 else if (TYPE_P (name))
220 else if (TREE_CODE (name) == IDENTIFIER_NODE)
222 if ((MAYBE_CLASS_TYPE_P (basetype)
223 && name == constructor_name (basetype))
224 || (TREE_CODE (basetype) == ENUMERAL_TYPE
225 && name == TYPE_IDENTIFIER (basetype)))
228 name = get_type_value (name);
234 template <class T> struct S { ~S(); };
238 NAME will be a class template. */
239 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
243 if (!name || name == error_mark_node)
245 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
248 /* We want the address of a function or method. We avoid creating a
249 pointer-to-member function. */
252 build_addr_func (tree function)
254 tree type = TREE_TYPE (function);
256 /* We have to do these by hand to avoid real pointer to member
258 if (TREE_CODE (type) == METHOD_TYPE)
260 if (TREE_CODE (function) == OFFSET_REF)
262 tree object = build_address (TREE_OPERAND (function, 0));
263 return get_member_function_from_ptrfunc (&object,
264 TREE_OPERAND (function, 1));
266 function = build_address (function);
269 function = decay_conversion (function);
274 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
275 POINTER_TYPE to those. Note, pointer to member function types
276 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
277 two variants. build_call_a is the primitive taking an array of
278 arguments, while build_call_n is a wrapper that handles varargs. */
281 build_call_n (tree function, int n, ...)
284 return build_call_a (function, 0, NULL);
287 tree *argarray = (tree *) alloca (n * sizeof (tree));
292 for (i = 0; i < n; i++)
293 argarray[i] = va_arg (ap, tree);
295 return build_call_a (function, n, argarray);
300 build_call_a (tree function, int n, tree *argarray)
302 int is_constructor = 0;
309 function = build_addr_func (function);
311 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
312 fntype = TREE_TYPE (TREE_TYPE (function));
313 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
314 || TREE_CODE (fntype) == METHOD_TYPE);
315 result_type = TREE_TYPE (fntype);
316 /* An rvalue has no cv-qualifiers. */
317 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
318 result_type = cv_unqualified (result_type);
320 if (TREE_CODE (function) == ADDR_EXPR
321 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
323 decl = TREE_OPERAND (function, 0);
324 if (!TREE_USED (decl))
326 /* We invoke build_call directly for several library
327 functions. These may have been declared normally if
328 we're building libgcc, so we can't just check
330 gcc_assert (DECL_ARTIFICIAL (decl)
331 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
339 /* We check both the decl and the type; a function may be known not to
340 throw without being declared throw(). */
341 nothrow = ((decl && TREE_NOTHROW (decl))
342 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
344 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
345 current_function_returns_abnormally = 1;
347 if (decl && TREE_DEPRECATED (decl))
348 warn_deprecated_use (decl, NULL_TREE);
349 require_complete_eh_spec_types (fntype, decl);
351 if (decl && DECL_CONSTRUCTOR_P (decl))
354 /* Don't pass empty class objects by value. This is useful
355 for tags in STL, which are used to control overload resolution.
356 We don't need to handle other cases of copying empty classes. */
357 if (! decl || ! DECL_BUILT_IN (decl))
358 for (i = 0; i < n; i++)
359 if (is_empty_class (TREE_TYPE (argarray[i]))
360 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
362 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
363 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
367 function = build_call_array_loc (input_location,
368 result_type, function, n, argarray);
369 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
370 TREE_NOTHROW (function) = nothrow;
375 /* Build something of the form ptr->method (args)
376 or object.method (args). This can also build
377 calls to constructors, and find friends.
379 Member functions always take their class variable
382 INSTANCE is a class instance.
384 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
386 PARMS help to figure out what that NAME really refers to.
388 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
389 down to the real instance type to use for access checking. We need this
390 information to get protected accesses correct.
392 FLAGS is the logical disjunction of zero or more LOOKUP_
393 flags. See cp-tree.h for more info.
395 If this is all OK, calls build_function_call with the resolved
398 This function must also handle being called to perform
399 initialization, promotion/coercion of arguments, and
400 instantiation of default parameters.
402 Note that NAME may refer to an instance variable name. If
403 `operator()()' is defined for the type of that field, then we return
406 /* New overloading code. */
408 typedef struct z_candidate z_candidate;
410 typedef struct candidate_warning candidate_warning;
411 struct candidate_warning {
413 candidate_warning *next;
417 /* The FUNCTION_DECL that will be called if this candidate is
418 selected by overload resolution. */
420 /* If not NULL_TREE, the first argument to use when calling this
423 /* The rest of the arguments to use when calling this function. If
424 there are no further arguments this may be NULL or it may be an
426 const VEC(tree,gc) *args;
427 /* The implicit conversion sequences for each of the arguments to
430 /* The number of implicit conversion sequences. */
432 /* If FN is a user-defined conversion, the standard conversion
433 sequence from the type returned by FN to the desired destination
435 conversion *second_conv;
437 /* If FN is a member function, the binfo indicating the path used to
438 qualify the name of FN at the call site. This path is used to
439 determine whether or not FN is accessible if it is selected by
440 overload resolution. The DECL_CONTEXT of FN will always be a
441 (possibly improper) base of this binfo. */
443 /* If FN is a non-static member function, the binfo indicating the
444 subobject to which the `this' pointer should be converted if FN
445 is selected by overload resolution. The type pointed to the by
446 the `this' pointer must correspond to the most derived class
447 indicated by the CONVERSION_PATH. */
448 tree conversion_path;
450 candidate_warning *warnings;
454 /* Returns true iff T is a null pointer constant in the sense of
458 null_ptr_cst_p (tree t)
462 A null pointer constant is an integral constant expression
463 (_expr.const_) rvalue of integer type that evaluates to zero. */
464 t = integral_constant_value (t);
467 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
470 if (!TREE_OVERFLOW (t))
476 /* Returns nonzero if PARMLIST consists of only default parms and/or
480 sufficient_parms_p (const_tree parmlist)
482 for (; parmlist && parmlist != void_list_node;
483 parmlist = TREE_CHAIN (parmlist))
484 if (!TREE_PURPOSE (parmlist))
489 /* Allocate N bytes of memory from the conversion obstack. The memory
490 is zeroed before being returned. */
493 conversion_obstack_alloc (size_t n)
496 if (!conversion_obstack_initialized)
498 gcc_obstack_init (&conversion_obstack);
499 conversion_obstack_initialized = true;
501 p = obstack_alloc (&conversion_obstack, n);
506 /* Dynamically allocate a conversion. */
509 alloc_conversion (conversion_kind kind)
512 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
517 #ifdef ENABLE_CHECKING
519 /* Make sure that all memory on the conversion obstack has been
523 validate_conversion_obstack (void)
525 if (conversion_obstack_initialized)
526 gcc_assert ((obstack_next_free (&conversion_obstack)
527 == obstack_base (&conversion_obstack)));
530 #endif /* ENABLE_CHECKING */
532 /* Dynamically allocate an array of N conversions. */
535 alloc_conversions (size_t n)
537 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
541 build_conv (conversion_kind code, tree type, conversion *from)
544 conversion_rank rank = CONVERSION_RANK (from);
546 /* Note that the caller is responsible for filling in t->cand for
547 user-defined conversions. */
548 t = alloc_conversion (code);
571 t->user_conv_p = (code == ck_user || from->user_conv_p);
572 t->bad_p = from->bad_p;
577 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
578 specialization of std::initializer_list<T>, if such a conversion is
582 build_list_conv (tree type, tree ctor, int flags)
584 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
585 unsigned len = CONSTRUCTOR_NELTS (ctor);
586 conversion **subconvs = alloc_conversions (len);
591 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
594 = implicit_conversion (elttype, TREE_TYPE (val), val,
602 t = alloc_conversion (ck_list);
604 t->u.list = subconvs;
607 for (i = 0; i < len; ++i)
609 conversion *sub = subconvs[i];
610 if (sub->rank > t->rank)
612 if (sub->user_conv_p)
613 t->user_conv_p = true;
621 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
622 aggregate class, if such a conversion is possible. */
625 build_aggr_conv (tree type, tree ctor, int flags)
627 unsigned HOST_WIDE_INT i = 0;
629 tree field = next_initializable_field (TYPE_FIELDS (type));
631 for (; field; field = next_initializable_field (TREE_CHAIN (field)))
633 if (i < CONSTRUCTOR_NELTS (ctor))
635 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
636 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
640 if (TREE_CODE (type) == UNION_TYPE)
643 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
647 if (i < CONSTRUCTOR_NELTS (ctor))
650 c = alloc_conversion (ck_aggr);
653 c->user_conv_p = true;
658 /* Build a representation of the identity conversion from EXPR to
659 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
662 build_identity_conv (tree type, tree expr)
666 c = alloc_conversion (ck_identity);
673 /* Converting from EXPR to TYPE was ambiguous in the sense that there
674 were multiple user-defined conversions to accomplish the job.
675 Build a conversion that indicates that ambiguity. */
678 build_ambiguous_conv (tree type, tree expr)
682 c = alloc_conversion (ck_ambig);
690 strip_top_quals (tree t)
692 if (TREE_CODE (t) == ARRAY_TYPE)
694 return cp_build_qualified_type (t, 0);
697 /* Returns the standard conversion path (see [conv]) from type FROM to type
698 TO, if any. For proper handling of null pointer constants, you must
699 also pass the expression EXPR to convert from. If C_CAST_P is true,
700 this conversion is coming from a C-style cast. */
703 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
706 enum tree_code fcode, tcode;
708 bool fromref = false;
710 to = non_reference (to);
711 if (TREE_CODE (from) == REFERENCE_TYPE)
714 from = TREE_TYPE (from);
716 to = strip_top_quals (to);
717 from = strip_top_quals (from);
719 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
720 && expr && type_unknown_p (expr))
722 tsubst_flags_t tflags = tf_conv;
723 if (!(flags & LOOKUP_PROTECT))
724 tflags |= tf_no_access_control;
725 expr = instantiate_type (to, expr, tflags);
726 if (expr == error_mark_node)
728 from = TREE_TYPE (expr);
731 fcode = TREE_CODE (from);
732 tcode = TREE_CODE (to);
734 conv = build_identity_conv (from, expr);
735 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
737 from = type_decays_to (from);
738 fcode = TREE_CODE (from);
739 conv = build_conv (ck_lvalue, from, conv);
741 else if (fromref || (expr && lvalue_p (expr)))
746 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
749 from = strip_top_quals (bitfield_type);
750 fcode = TREE_CODE (from);
753 conv = build_conv (ck_rvalue, from, conv);
756 /* Allow conversion between `__complex__' data types. */
757 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
759 /* The standard conversion sequence to convert FROM to TO is
760 the standard conversion sequence to perform componentwise
762 conversion *part_conv = standard_conversion
763 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
767 conv = build_conv (part_conv->kind, to, conv);
768 conv->rank = part_conv->rank;
776 if (same_type_p (from, to))
779 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
780 && expr && null_ptr_cst_p (expr))
781 conv = build_conv (ck_std, to, conv);
782 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
783 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
785 /* For backwards brain damage compatibility, allow interconversion of
786 pointers and integers with a pedwarn. */
787 conv = build_conv (ck_std, to, conv);
790 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
792 /* For backwards brain damage compatibility, allow interconversion of
793 enums and integers with a pedwarn. */
794 conv = build_conv (ck_std, to, conv);
797 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
798 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
803 if (tcode == POINTER_TYPE
804 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
807 else if (VOID_TYPE_P (TREE_TYPE (to))
808 && !TYPE_PTRMEM_P (from)
809 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
811 from = build_pointer_type
812 (cp_build_qualified_type (void_type_node,
813 cp_type_quals (TREE_TYPE (from))));
814 conv = build_conv (ck_ptr, from, conv);
816 else if (TYPE_PTRMEM_P (from))
818 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
819 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
821 if (DERIVED_FROM_P (fbase, tbase)
822 && (same_type_ignoring_top_level_qualifiers_p
823 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
824 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
826 from = build_ptrmem_type (tbase,
827 TYPE_PTRMEM_POINTED_TO_TYPE (from));
828 conv = build_conv (ck_pmem, from, conv);
830 else if (!same_type_p (fbase, tbase))
833 else if (CLASS_TYPE_P (TREE_TYPE (from))
834 && CLASS_TYPE_P (TREE_TYPE (to))
837 An rvalue of type "pointer to cv D," where D is a
838 class type, can be converted to an rvalue of type
839 "pointer to cv B," where B is a base class (clause
840 _class.derived_) of D. If B is an inaccessible
841 (clause _class.access_) or ambiguous
842 (_class.member.lookup_) base class of D, a program
843 that necessitates this conversion is ill-formed.
844 Therefore, we use DERIVED_FROM_P, and do not check
845 access or uniqueness. */
846 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
849 cp_build_qualified_type (TREE_TYPE (to),
850 cp_type_quals (TREE_TYPE (from)));
851 from = build_pointer_type (from);
852 conv = build_conv (ck_ptr, from, conv);
856 if (tcode == POINTER_TYPE)
858 to_pointee = TREE_TYPE (to);
859 from_pointee = TREE_TYPE (from);
863 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
864 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
867 if (same_type_p (from, to))
869 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
870 /* In a C-style cast, we ignore CV-qualification because we
871 are allowed to perform a static_cast followed by a
873 conv = build_conv (ck_qual, to, conv);
874 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
875 conv = build_conv (ck_qual, to, conv);
876 else if (expr && string_conv_p (to, expr, 0))
877 /* converting from string constant to char *. */
878 conv = build_conv (ck_qual, to, conv);
879 else if (ptr_reasonably_similar (to_pointee, from_pointee))
881 conv = build_conv (ck_ptr, to, conv);
889 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
891 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
892 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
893 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
894 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
896 if (!DERIVED_FROM_P (fbase, tbase)
897 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
898 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
899 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
900 || cp_type_quals (fbase) != cp_type_quals (tbase))
903 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
904 from = build_ptrmemfunc_type (build_pointer_type (from));
905 conv = build_conv (ck_pmem, from, conv);
908 else if (tcode == BOOLEAN_TYPE)
912 An rvalue of arithmetic, unscoped enumeration, pointer, or
913 pointer to member type can be converted to an rvalue of type
915 if (ARITHMETIC_TYPE_P (from)
916 || UNSCOPED_ENUM_P (from)
917 || fcode == POINTER_TYPE
918 || TYPE_PTR_TO_MEMBER_P (from))
920 conv = build_conv (ck_std, to, conv);
921 if (fcode == POINTER_TYPE
922 || TYPE_PTRMEM_P (from)
923 || (TYPE_PTRMEMFUNC_P (from)
924 && conv->rank < cr_pbool))
925 conv->rank = cr_pbool;
931 /* We don't check for ENUMERAL_TYPE here because there are no standard
932 conversions to enum type. */
933 /* As an extension, allow conversion to complex type. */
934 else if (ARITHMETIC_TYPE_P (to))
936 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
937 || SCOPED_ENUM_P (from))
939 conv = build_conv (ck_std, to, conv);
941 /* Give this a better rank if it's a promotion. */
942 if (same_type_p (to, type_promotes_to (from))
943 && conv->u.next->rank <= cr_promotion)
944 conv->rank = cr_promotion;
946 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
947 && vector_types_convertible_p (from, to, false))
948 return build_conv (ck_std, to, conv);
949 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
950 && is_properly_derived_from (from, to))
952 if (conv->kind == ck_rvalue)
954 conv = build_conv (ck_base, to, conv);
955 /* The derived-to-base conversion indicates the initialization
956 of a parameter with base type from an object of a derived
957 type. A temporary object is created to hold the result of
958 the conversion unless we're binding directly to a reference. */
959 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
964 if (flags & LOOKUP_NO_NARROWING)
965 conv->check_narrowing = true;
970 /* Returns nonzero if T1 is reference-related to T2. */
973 reference_related_p (tree t1, tree t2)
975 t1 = TYPE_MAIN_VARIANT (t1);
976 t2 = TYPE_MAIN_VARIANT (t2);
980 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
981 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
983 return (same_type_p (t1, t2)
984 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
985 && DERIVED_FROM_P (t1, t2)));
988 /* Returns nonzero if T1 is reference-compatible with T2. */
991 reference_compatible_p (tree t1, tree t2)
995 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
996 reference-related to T2 and cv1 is the same cv-qualification as,
997 or greater cv-qualification than, cv2. */
998 return (reference_related_p (t1, t2)
999 && at_least_as_qualified_p (t1, t2));
1002 /* Determine whether or not the EXPR (of class type S) can be
1003 converted to T as in [over.match.ref]. */
1006 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1012 struct z_candidate *candidates;
1013 struct z_candidate *cand;
1016 conversions = lookup_conversions (s, /*lookup_template_convs_p=*/true);
1022 Assuming that "cv1 T" is the underlying type of the reference
1023 being initialized, and "cv S" is the type of the initializer
1024 expression, with S a class type, the candidate functions are
1025 selected as follows:
1027 --The conversion functions of S and its base classes are
1028 considered. Those that are not hidden within S and yield type
1029 "reference to cv2 T2", where "cv1 T" is reference-compatible
1030 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1032 The argument list has one argument, which is the initializer
1037 /* Conceptually, we should take the address of EXPR and put it in
1038 the argument list. Unfortunately, however, that can result in
1039 error messages, which we should not issue now because we are just
1040 trying to find a conversion operator. Therefore, we use NULL,
1041 cast to the appropriate type. */
1042 first_arg = build_int_cst (build_pointer_type (s), 0);
1044 t = TREE_TYPE (reference_type);
1046 for (; conversions; conversions = TREE_CHAIN (conversions))
1048 tree fns = TREE_VALUE (conversions);
1050 for (; fns; fns = OVL_NEXT (fns))
1052 tree f = OVL_CURRENT (fns);
1053 tree t2 = TREE_TYPE (TREE_TYPE (f));
1055 if (DECL_NONCONVERTING_P (f)
1056 && (flags & LOOKUP_ONLYCONVERTING))
1061 /* If this is a template function, try to get an exact
1063 if (TREE_CODE (f) == TEMPLATE_DECL)
1065 cand = add_template_candidate (&candidates,
1072 TREE_PURPOSE (conversions),
1078 /* Now, see if the conversion function really returns
1079 an lvalue of the appropriate type. From the
1080 point of view of unification, simply returning an
1081 rvalue of the right type is good enough. */
1083 t2 = TREE_TYPE (TREE_TYPE (f));
1084 if (TREE_CODE (t2) != REFERENCE_TYPE
1085 || !reference_compatible_p (t, TREE_TYPE (t2)))
1087 candidates = candidates->next;
1092 else if (TREE_CODE (t2) == REFERENCE_TYPE
1093 && reference_compatible_p (t, TREE_TYPE (t2)))
1094 cand = add_function_candidate (&candidates, f, s, first_arg,
1095 NULL, TYPE_BINFO (s),
1096 TREE_PURPOSE (conversions),
1101 conversion *identity_conv;
1102 /* Build a standard conversion sequence indicating the
1103 binding from the reference type returned by the
1104 function to the desired REFERENCE_TYPE. */
1106 = build_identity_conv (TREE_TYPE (TREE_TYPE
1107 (TREE_TYPE (cand->fn))),
1110 = (direct_reference_binding
1111 (reference_type, identity_conv));
1112 cand->second_conv->rvaluedness_matches_p
1113 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1114 == TYPE_REF_IS_RVALUE (reference_type);
1115 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1117 /* Don't allow binding of lvalues to rvalue references. */
1118 if (TYPE_REF_IS_RVALUE (reference_type)
1119 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1120 cand->second_conv->bad_p = true;
1125 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1126 /* If none of the conversion functions worked out, let our caller
1131 cand = tourney (candidates);
1135 /* Now that we know that this is the function we're going to use fix
1136 the dummy first argument. */
1137 gcc_assert (cand->first_arg == NULL_TREE
1138 || integer_zerop (cand->first_arg));
1139 cand->first_arg = build_this (expr);
1141 /* Build a user-defined conversion sequence representing the
1143 conv = build_conv (ck_user,
1144 TREE_TYPE (TREE_TYPE (cand->fn)),
1145 build_identity_conv (TREE_TYPE (expr), expr));
1148 if (cand->viable == -1)
1151 /* Merge it with the standard conversion sequence from the
1152 conversion function's return type to the desired type. */
1153 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1155 return cand->second_conv;
1158 /* A reference of the indicated TYPE is being bound directly to the
1159 expression represented by the implicit conversion sequence CONV.
1160 Return a conversion sequence for this binding. */
1163 direct_reference_binding (tree type, conversion *conv)
1167 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1168 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1170 t = TREE_TYPE (type);
1174 When a parameter of reference type binds directly
1175 (_dcl.init.ref_) to an argument expression, the implicit
1176 conversion sequence is the identity conversion, unless the
1177 argument expression has a type that is a derived class of the
1178 parameter type, in which case the implicit conversion sequence is
1179 a derived-to-base Conversion.
1181 If the parameter binds directly to the result of applying a
1182 conversion function to the argument expression, the implicit
1183 conversion sequence is a user-defined conversion sequence
1184 (_over.ics.user_), with the second standard conversion sequence
1185 either an identity conversion or, if the conversion function
1186 returns an entity of a type that is a derived class of the
1187 parameter type, a derived-to-base conversion. */
1188 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1190 /* Represent the derived-to-base conversion. */
1191 conv = build_conv (ck_base, t, conv);
1192 /* We will actually be binding to the base-class subobject in
1193 the derived class, so we mark this conversion appropriately.
1194 That way, convert_like knows not to generate a temporary. */
1195 conv->need_temporary_p = false;
1197 return build_conv (ck_ref_bind, type, conv);
1200 /* Returns the conversion path from type FROM to reference type TO for
1201 purposes of reference binding. For lvalue binding, either pass a
1202 reference type to FROM or an lvalue expression to EXPR. If the
1203 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1204 the conversion returned. If C_CAST_P is true, this
1205 conversion is coming from a C-style cast. */
1208 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1210 conversion *conv = NULL;
1211 tree to = TREE_TYPE (rto);
1216 cp_lvalue_kind is_lvalue = clk_none;
1218 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1220 expr = instantiate_type (to, expr, tf_none);
1221 if (expr == error_mark_node)
1223 from = TREE_TYPE (expr);
1226 if (TREE_CODE (from) == REFERENCE_TYPE)
1228 /* Anything with reference type is an lvalue. */
1229 is_lvalue = clk_ordinary;
1230 from = TREE_TYPE (from);
1233 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1235 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1236 conv = implicit_conversion (to, from, expr, c_cast_p,
1238 if (!CLASS_TYPE_P (to)
1239 && CONSTRUCTOR_NELTS (expr) == 1)
1241 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1242 if (error_operand_p (expr))
1244 from = TREE_TYPE (expr);
1248 if (is_lvalue == clk_none && expr)
1249 is_lvalue = real_lvalue_p (expr);
1252 if ((is_lvalue & clk_bitfield) != 0)
1253 tfrom = unlowered_expr_type (expr);
1255 /* Figure out whether or not the types are reference-related and
1256 reference compatible. We have do do this after stripping
1257 references from FROM. */
1258 related_p = reference_related_p (to, tfrom);
1259 /* If this is a C cast, first convert to an appropriately qualified
1260 type, so that we can later do a const_cast to the desired type. */
1261 if (related_p && c_cast_p
1262 && !at_least_as_qualified_p (to, tfrom))
1263 to = build_qualified_type (to, cp_type_quals (tfrom));
1264 compatible_p = reference_compatible_p (to, tfrom);
1266 /* Directly bind reference when target expression's type is compatible with
1267 the reference and expression is an lvalue. In DR391, the wording in
1268 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1269 const and rvalue references to rvalues of compatible class type.
1270 We should also do direct bindings for non-class "rvalues" derived from
1271 rvalue references. */
1274 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1275 && !(flags & LOOKUP_NO_TEMP_BIND))
1276 || TYPE_REF_IS_RVALUE (rto))
1277 && (CLASS_TYPE_P (from) || (expr && lvalue_p (expr))))))
1281 If the initializer expression
1283 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1284 is reference-compatible with "cv2 T2,"
1286 the reference is bound directly to the initializer expression
1290 If the initializer expression is an rvalue, with T2 a class type,
1291 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1292 is bound to the object represented by the rvalue or to a sub-object
1293 within that object. */
1295 conv = build_identity_conv (tfrom, expr);
1296 conv = direct_reference_binding (rto, conv);
1298 if (flags & LOOKUP_PREFER_RVALUE)
1299 /* The top-level caller requested that we pretend that the lvalue
1300 be treated as an rvalue. */
1301 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1303 conv->rvaluedness_matches_p
1304 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1306 if ((is_lvalue & clk_bitfield) != 0
1307 || ((is_lvalue & clk_packed) != 0 && !TYPE_PACKED (to)))
1308 /* For the purposes of overload resolution, we ignore the fact
1309 this expression is a bitfield or packed field. (In particular,
1310 [over.ics.ref] says specifically that a function with a
1311 non-const reference parameter is viable even if the
1312 argument is a bitfield.)
1314 However, when we actually call the function we must create
1315 a temporary to which to bind the reference. If the
1316 reference is volatile, or isn't const, then we cannot make
1317 a temporary, so we just issue an error when the conversion
1319 conv->need_temporary_p = true;
1321 /* Don't allow binding of lvalues to rvalue references. */
1322 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1323 && !(flags & LOOKUP_PREFER_RVALUE))
1328 /* [class.conv.fct] A conversion function is never used to convert a
1329 (possibly cv-qualified) object to the (possibly cv-qualified) same
1330 object type (or a reference to it), to a (possibly cv-qualified) base
1331 class of that type (or a reference to it).... */
1332 else if (CLASS_TYPE_P (from) && !related_p
1333 && !(flags & LOOKUP_NO_CONVERSION))
1337 If the initializer expression
1339 -- has a class type (i.e., T2 is a class type) can be
1340 implicitly converted to an lvalue of type "cv3 T3," where
1341 "cv1 T1" is reference-compatible with "cv3 T3". (this
1342 conversion is selected by enumerating the applicable
1343 conversion functions (_over.match.ref_) and choosing the
1344 best one through overload resolution. (_over.match_).
1346 the reference is bound to the lvalue result of the conversion
1347 in the second case. */
1348 conv = convert_class_to_reference (rto, from, expr, flags);
1353 /* From this point on, we conceptually need temporaries, even if we
1354 elide them. Only the cases above are "direct bindings". */
1355 if (flags & LOOKUP_NO_TEMP_BIND)
1360 When a parameter of reference type is not bound directly to an
1361 argument expression, the conversion sequence is the one required
1362 to convert the argument expression to the underlying type of the
1363 reference according to _over.best.ics_. Conceptually, this
1364 conversion sequence corresponds to copy-initializing a temporary
1365 of the underlying type with the argument expression. Any
1366 difference in top-level cv-qualification is subsumed by the
1367 initialization itself and does not constitute a conversion. */
1371 Otherwise, the reference shall be to a non-volatile const type.
1373 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1374 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1379 Otherwise, a temporary of type "cv1 T1" is created and
1380 initialized from the initializer expression using the rules for a
1381 non-reference copy initialization. If T1 is reference-related to
1382 T2, cv1 must be the same cv-qualification as, or greater
1383 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1384 if (related_p && !at_least_as_qualified_p (to, from))
1387 /* We're generating a temporary now, but don't bind any more in the
1388 conversion (specifically, don't slice the temporary returned by a
1389 conversion operator). */
1390 flags |= LOOKUP_NO_TEMP_BIND;
1392 /* Temporaries are copy-initialized, except for this hack to allow
1393 explicit conversion ops to the copy ctor. See also
1394 add_function_candidate. */
1395 if (!(flags & LOOKUP_COPY_PARM))
1396 flags |= LOOKUP_ONLYCONVERTING;
1399 conv = implicit_conversion (to, from, expr, c_cast_p,
1404 conv = build_conv (ck_ref_bind, rto, conv);
1405 /* This reference binding, unlike those above, requires the
1406 creation of a temporary. */
1407 conv->need_temporary_p = true;
1408 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1413 /* Returns the implicit conversion sequence (see [over.ics]) from type
1414 FROM to type TO. The optional expression EXPR may affect the
1415 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1416 true, this conversion is coming from a C-style cast. */
1419 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1424 if (from == error_mark_node || to == error_mark_node
1425 || expr == error_mark_node)
1428 if (TREE_CODE (to) == REFERENCE_TYPE)
1429 conv = reference_binding (to, from, expr, c_cast_p, flags);
1431 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1436 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1438 if (is_std_init_list (to))
1439 return build_list_conv (to, expr, flags);
1441 /* Allow conversion from an initializer-list with one element to a
1443 if (SCALAR_TYPE_P (to))
1445 int nelts = CONSTRUCTOR_NELTS (expr);
1449 elt = integer_zero_node;
1450 else if (nelts == 1)
1451 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1453 elt = error_mark_node;
1455 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1459 conv->check_narrowing = true;
1460 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1461 /* Too many levels of braces, i.e. '{{1}}'. */
1468 if (expr != NULL_TREE
1469 && (MAYBE_CLASS_TYPE_P (from)
1470 || MAYBE_CLASS_TYPE_P (to))
1471 && (flags & LOOKUP_NO_CONVERSION) == 0)
1473 struct z_candidate *cand;
1474 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING));
1476 if (CLASS_TYPE_P (to)
1477 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1478 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1479 return build_aggr_conv (to, expr, flags);
1481 cand = build_user_type_conversion_1 (to, expr, convflags);
1483 conv = cand->second_conv;
1485 /* We used to try to bind a reference to a temporary here, but that
1486 is now handled after the recursive call to this function at the end
1487 of reference_binding. */
1494 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1495 functions. ARGS will not be changed until a single candidate is
1498 static struct z_candidate *
1499 add_candidate (struct z_candidate **candidates,
1500 tree fn, tree first_arg, const VEC(tree,gc) *args,
1501 size_t num_convs, conversion **convs,
1502 tree access_path, tree conversion_path,
1505 struct z_candidate *cand = (struct z_candidate *)
1506 conversion_obstack_alloc (sizeof (struct z_candidate));
1509 cand->first_arg = first_arg;
1511 cand->convs = convs;
1512 cand->num_convs = num_convs;
1513 cand->access_path = access_path;
1514 cand->conversion_path = conversion_path;
1515 cand->viable = viable;
1516 cand->next = *candidates;
1522 /* Create an overload candidate for the function or method FN called
1523 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1524 FLAGS is passed on to implicit_conversion.
1526 This does not change ARGS.
1528 CTYPE, if non-NULL, is the type we want to pretend this function
1529 comes from for purposes of overload resolution. */
1531 static struct z_candidate *
1532 add_function_candidate (struct z_candidate **candidates,
1533 tree fn, tree ctype, tree first_arg,
1534 const VEC(tree,gc) *args, tree access_path,
1535 tree conversion_path, int flags)
1537 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1541 tree orig_first_arg = first_arg;
1545 /* At this point we should not see any functions which haven't been
1546 explicitly declared, except for friend functions which will have
1547 been found using argument dependent lookup. */
1548 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1550 /* The `this', `in_chrg' and VTT arguments to constructors are not
1551 considered in overload resolution. */
1552 if (DECL_CONSTRUCTOR_P (fn))
1554 parmlist = skip_artificial_parms_for (fn, parmlist);
1555 skip = num_artificial_parms_for (fn);
1556 if (skip > 0 && first_arg != NULL_TREE)
1559 first_arg = NULL_TREE;
1565 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1566 convs = alloc_conversions (len);
1568 /* 13.3.2 - Viable functions [over.match.viable]
1569 First, to be a viable function, a candidate function shall have enough
1570 parameters to agree in number with the arguments in the list.
1572 We need to check this first; otherwise, checking the ICSes might cause
1573 us to produce an ill-formed template instantiation. */
1575 parmnode = parmlist;
1576 for (i = 0; i < len; ++i)
1578 if (parmnode == NULL_TREE || parmnode == void_list_node)
1580 parmnode = TREE_CHAIN (parmnode);
1583 if (i < len && parmnode)
1586 /* Make sure there are default args for the rest of the parms. */
1587 else if (!sufficient_parms_p (parmnode))
1593 /* Second, for F to be a viable function, there shall exist for each
1594 argument an implicit conversion sequence that converts that argument
1595 to the corresponding parameter of F. */
1597 parmnode = parmlist;
1599 for (i = 0; i < len; ++i)
1605 if (parmnode == void_list_node)
1608 if (i == 0 && first_arg != NULL_TREE)
1611 arg = VEC_index (tree, args,
1612 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1613 argtype = lvalue_type (arg);
1615 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1616 && ! DECL_CONSTRUCTOR_P (fn));
1620 tree parmtype = TREE_VALUE (parmnode);
1623 /* The type of the implicit object parameter ('this') for
1624 overload resolution is not always the same as for the
1625 function itself; conversion functions are considered to
1626 be members of the class being converted, and functions
1627 introduced by a using-declaration are considered to be
1628 members of the class that uses them.
1630 Since build_over_call ignores the ICS for the `this'
1631 parameter, we can just change the parm type. */
1632 if (ctype && is_this)
1635 = build_qualified_type (ctype,
1636 TYPE_QUALS (TREE_TYPE (parmtype)));
1637 parmtype = build_pointer_type (parmtype);
1640 if (ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn)
1643 /* Hack: Direct-initialize copy parm (i.e. suppress
1644 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1645 work. See also reference_binding. */
1646 lflags |= LOOKUP_COPY_PARM;
1647 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1648 lflags |= LOOKUP_NO_CONVERSION;
1651 lflags |= LOOKUP_ONLYCONVERTING;
1653 t = implicit_conversion (parmtype, argtype, arg,
1654 /*c_cast_p=*/false, lflags);
1658 t = build_identity_conv (argtype, arg);
1659 t->ellipsis_p = true;
1676 parmnode = TREE_CHAIN (parmnode);
1680 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1681 access_path, conversion_path, viable);
1684 /* Create an overload candidate for the conversion function FN which will
1685 be invoked for expression OBJ, producing a pointer-to-function which
1686 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1687 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1688 passed on to implicit_conversion.
1690 Actually, we don't really care about FN; we care about the type it
1691 converts to. There may be multiple conversion functions that will
1692 convert to that type, and we rely on build_user_type_conversion_1 to
1693 choose the best one; so when we create our candidate, we record the type
1694 instead of the function. */
1696 static struct z_candidate *
1697 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1698 tree first_arg, const VEC(tree,gc) *arglist,
1699 tree access_path, tree conversion_path)
1701 tree totype = TREE_TYPE (TREE_TYPE (fn));
1702 int i, len, viable, flags;
1703 tree parmlist, parmnode;
1706 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1707 parmlist = TREE_TYPE (parmlist);
1708 parmlist = TYPE_ARG_TYPES (parmlist);
1710 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1711 convs = alloc_conversions (len);
1712 parmnode = parmlist;
1714 flags = LOOKUP_IMPLICIT;
1716 /* Don't bother looking up the same type twice. */
1717 if (*candidates && (*candidates)->fn == totype)
1720 for (i = 0; i < len; ++i)
1727 else if (i == 1 && first_arg != NULL_TREE)
1730 arg = VEC_index (tree, arglist,
1731 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1732 argtype = lvalue_type (arg);
1735 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1737 else if (parmnode == void_list_node)
1740 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1741 /*c_cast_p=*/false, flags);
1744 t = build_identity_conv (argtype, arg);
1745 t->ellipsis_p = true;
1759 parmnode = TREE_CHAIN (parmnode);
1765 if (!sufficient_parms_p (parmnode))
1768 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1769 access_path, conversion_path, viable);
1773 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1774 tree type1, tree type2, tree *args, tree *argtypes,
1786 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1787 convs = alloc_conversions (num_convs);
1789 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
1790 conversion ops are allowed. We handle that here by just checking for
1791 boolean_type_node because other operators don't ask for it. COND_EXPR
1792 also does contextual conversion to bool for the first operand, but we
1793 handle that in build_conditional_expr, and type1 here is operand 2. */
1794 if (type1 != boolean_type_node)
1795 flags |= LOOKUP_ONLYCONVERTING;
1797 for (i = 0; i < 2; ++i)
1802 t = implicit_conversion (types[i], argtypes[i], args[i],
1803 /*c_cast_p=*/false, flags);
1807 /* We need something for printing the candidate. */
1808 t = build_identity_conv (types[i], NULL_TREE);
1815 /* For COND_EXPR we rearranged the arguments; undo that now. */
1818 convs[2] = convs[1];
1819 convs[1] = convs[0];
1820 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1821 /*c_cast_p=*/false, flags);
1828 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1830 /*access_path=*/NULL_TREE,
1831 /*conversion_path=*/NULL_TREE,
1836 is_complete (tree t)
1838 return COMPLETE_TYPE_P (complete_type (t));
1841 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1844 promoted_arithmetic_type_p (tree type)
1848 In this section, the term promoted integral type is used to refer
1849 to those integral types which are preserved by integral promotion
1850 (including e.g. int and long but excluding e.g. char).
1851 Similarly, the term promoted arithmetic type refers to promoted
1852 integral types plus floating types. */
1853 return ((CP_INTEGRAL_TYPE_P (type)
1854 && same_type_p (type_promotes_to (type), type))
1855 || TREE_CODE (type) == REAL_TYPE);
1858 /* Create any builtin operator overload candidates for the operator in
1859 question given the converted operand types TYPE1 and TYPE2. The other
1860 args are passed through from add_builtin_candidates to
1861 build_builtin_candidate.
1863 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1864 If CODE is requires candidates operands of the same type of the kind
1865 of which TYPE1 and TYPE2 are, we add both candidates
1866 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1869 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1870 enum tree_code code2, tree fnname, tree type1,
1871 tree type2, tree *args, tree *argtypes, int flags)
1875 case POSTINCREMENT_EXPR:
1876 case POSTDECREMENT_EXPR:
1877 args[1] = integer_zero_node;
1878 type2 = integer_type_node;
1887 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1888 and VQ is either volatile or empty, there exist candidate operator
1889 functions of the form
1890 VQ T& operator++(VQ T&);
1891 T operator++(VQ T&, int);
1892 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1893 type other than bool, and VQ is either volatile or empty, there exist
1894 candidate operator functions of the form
1895 VQ T& operator--(VQ T&);
1896 T operator--(VQ T&, int);
1897 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1898 complete object type, and VQ is either volatile or empty, there exist
1899 candidate operator functions of the form
1900 T*VQ& operator++(T*VQ&);
1901 T*VQ& operator--(T*VQ&);
1902 T* operator++(T*VQ&, int);
1903 T* operator--(T*VQ&, int); */
1905 case POSTDECREMENT_EXPR:
1906 case PREDECREMENT_EXPR:
1907 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1909 case POSTINCREMENT_EXPR:
1910 case PREINCREMENT_EXPR:
1911 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1913 type1 = build_reference_type (type1);
1918 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1919 exist candidate operator functions of the form
1923 8 For every function type T, there exist candidate operator functions of
1925 T& operator*(T*); */
1928 if (TREE_CODE (type1) == POINTER_TYPE
1929 && (TYPE_PTROB_P (type1)
1930 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1934 /* 9 For every type T, there exist candidate operator functions of the form
1937 10For every promoted arithmetic type T, there exist candidate operator
1938 functions of the form
1942 case UNARY_PLUS_EXPR: /* unary + */
1943 if (TREE_CODE (type1) == POINTER_TYPE)
1946 if (ARITHMETIC_TYPE_P (type1))
1950 /* 11For every promoted integral type T, there exist candidate operator
1951 functions of the form
1955 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1959 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1960 is the same type as C2 or is a derived class of C2, T is a complete
1961 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1962 there exist candidate operator functions of the form
1963 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1964 where CV12 is the union of CV1 and CV2. */
1967 if (TREE_CODE (type1) == POINTER_TYPE
1968 && TYPE_PTR_TO_MEMBER_P (type2))
1970 tree c1 = TREE_TYPE (type1);
1971 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1973 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1974 && (TYPE_PTRMEMFUNC_P (type2)
1975 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1980 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1981 didate operator functions of the form
1986 bool operator<(L, R);
1987 bool operator>(L, R);
1988 bool operator<=(L, R);
1989 bool operator>=(L, R);
1990 bool operator==(L, R);
1991 bool operator!=(L, R);
1992 where LR is the result of the usual arithmetic conversions between
1995 14For every pair of types T and I, where T is a cv-qualified or cv-
1996 unqualified complete object type and I is a promoted integral type,
1997 there exist candidate operator functions of the form
1998 T* operator+(T*, I);
1999 T& operator[](T*, I);
2000 T* operator-(T*, I);
2001 T* operator+(I, T*);
2002 T& operator[](I, T*);
2004 15For every T, where T is a pointer to complete object type, there exist
2005 candidate operator functions of the form112)
2006 ptrdiff_t operator-(T, T);
2008 16For every pointer or enumeration type T, there exist candidate operator
2009 functions of the form
2010 bool operator<(T, T);
2011 bool operator>(T, T);
2012 bool operator<=(T, T);
2013 bool operator>=(T, T);
2014 bool operator==(T, T);
2015 bool operator!=(T, T);
2017 17For every pointer to member type T, there exist candidate operator
2018 functions of the form
2019 bool operator==(T, T);
2020 bool operator!=(T, T); */
2023 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2025 if (TYPE_PTROB_P (type1)
2026 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2028 type2 = ptrdiff_type_node;
2032 case TRUNC_DIV_EXPR:
2033 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2039 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2040 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2042 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2047 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2059 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2061 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2063 if (TREE_CODE (type1) == ENUMERAL_TYPE
2064 && TREE_CODE (type2) == ENUMERAL_TYPE)
2066 if (TYPE_PTR_P (type1)
2067 && null_ptr_cst_p (args[1])
2068 && !uses_template_parms (type1))
2073 if (null_ptr_cst_p (args[0])
2074 && TYPE_PTR_P (type2)
2075 && !uses_template_parms (type2))
2083 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2086 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2088 type1 = ptrdiff_type_node;
2091 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2093 type2 = ptrdiff_type_node;
2098 /* 18For every pair of promoted integral types L and R, there exist candi-
2099 date operator functions of the form
2106 where LR is the result of the usual arithmetic conversions between
2109 case TRUNC_MOD_EXPR:
2115 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2119 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2120 type, VQ is either volatile or empty, and R is a promoted arithmetic
2121 type, there exist candidate operator functions of the form
2122 VQ L& operator=(VQ L&, R);
2123 VQ L& operator*=(VQ L&, R);
2124 VQ L& operator/=(VQ L&, R);
2125 VQ L& operator+=(VQ L&, R);
2126 VQ L& operator-=(VQ L&, R);
2128 20For every pair T, VQ), where T is any type and VQ is either volatile
2129 or empty, there exist candidate operator functions of the form
2130 T*VQ& operator=(T*VQ&, T*);
2132 21For every pair T, VQ), where T is a pointer to member type and VQ is
2133 either volatile or empty, there exist candidate operator functions of
2135 VQ T& operator=(VQ T&, T);
2137 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2138 unqualified complete object type, VQ is either volatile or empty, and
2139 I is a promoted integral type, there exist candidate operator func-
2141 T*VQ& operator+=(T*VQ&, I);
2142 T*VQ& operator-=(T*VQ&, I);
2144 23For every triple L, VQ, R), where L is an integral or enumeration
2145 type, VQ is either volatile or empty, and R is a promoted integral
2146 type, there exist candidate operator functions of the form
2148 VQ L& operator%=(VQ L&, R);
2149 VQ L& operator<<=(VQ L&, R);
2150 VQ L& operator>>=(VQ L&, R);
2151 VQ L& operator&=(VQ L&, R);
2152 VQ L& operator^=(VQ L&, R);
2153 VQ L& operator|=(VQ L&, R); */
2160 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2162 type2 = ptrdiff_type_node;
2166 case TRUNC_DIV_EXPR:
2167 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2171 case TRUNC_MOD_EXPR:
2177 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2182 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2184 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2185 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2186 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2187 || ((TYPE_PTRMEMFUNC_P (type1)
2188 || TREE_CODE (type1) == POINTER_TYPE)
2189 && null_ptr_cst_p (args[1])))
2199 type1 = build_reference_type (type1);
2205 For every pair of promoted arithmetic types L and R, there
2206 exist candidate operator functions of the form
2208 LR operator?(bool, L, R);
2210 where LR is the result of the usual arithmetic conversions
2211 between types L and R.
2213 For every type T, where T is a pointer or pointer-to-member
2214 type, there exist candidate operator functions of the form T
2215 operator?(bool, T, T); */
2217 if (promoted_arithmetic_type_p (type1)
2218 && promoted_arithmetic_type_p (type2))
2222 /* Otherwise, the types should be pointers. */
2223 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2224 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2227 /* We don't check that the two types are the same; the logic
2228 below will actually create two candidates; one in which both
2229 parameter types are TYPE1, and one in which both parameter
2237 /* If we're dealing with two pointer types or two enumeral types,
2238 we need candidates for both of them. */
2239 if (type2 && !same_type_p (type1, type2)
2240 && TREE_CODE (type1) == TREE_CODE (type2)
2241 && (TREE_CODE (type1) == REFERENCE_TYPE
2242 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2243 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2244 || TYPE_PTRMEMFUNC_P (type1)
2245 || MAYBE_CLASS_TYPE_P (type1)
2246 || TREE_CODE (type1) == ENUMERAL_TYPE))
2248 build_builtin_candidate
2249 (candidates, fnname, type1, type1, args, argtypes, flags);
2250 build_builtin_candidate
2251 (candidates, fnname, type2, type2, args, argtypes, flags);
2255 build_builtin_candidate
2256 (candidates, fnname, type1, type2, args, argtypes, flags);
2260 type_decays_to (tree type)
2262 if (TREE_CODE (type) == ARRAY_TYPE)
2263 return build_pointer_type (TREE_TYPE (type));
2264 if (TREE_CODE (type) == FUNCTION_TYPE)
2265 return build_pointer_type (type);
2266 if (!MAYBE_CLASS_TYPE_P (type))
2267 type = cv_unqualified (type);
2271 /* There are three conditions of builtin candidates:
2273 1) bool-taking candidates. These are the same regardless of the input.
2274 2) pointer-pair taking candidates. These are generated for each type
2275 one of the input types converts to.
2276 3) arithmetic candidates. According to the standard, we should generate
2277 all of these, but I'm trying not to...
2279 Here we generate a superset of the possible candidates for this particular
2280 case. That is a subset of the full set the standard defines, plus some
2281 other cases which the standard disallows. add_builtin_candidate will
2282 filter out the invalid set. */
2285 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2286 enum tree_code code2, tree fnname, tree *args,
2291 tree type, argtypes[3];
2292 /* TYPES[i] is the set of possible builtin-operator parameter types
2293 we will consider for the Ith argument. These are represented as
2294 a TREE_LIST; the TREE_VALUE of each node is the potential
2298 for (i = 0; i < 3; ++i)
2301 argtypes[i] = unlowered_expr_type (args[i]);
2303 argtypes[i] = NULL_TREE;
2308 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2309 and VQ is either volatile or empty, there exist candidate operator
2310 functions of the form
2311 VQ T& operator++(VQ T&); */
2313 case POSTINCREMENT_EXPR:
2314 case PREINCREMENT_EXPR:
2315 case POSTDECREMENT_EXPR:
2316 case PREDECREMENT_EXPR:
2321 /* 24There also exist candidate operator functions of the form
2322 bool operator!(bool);
2323 bool operator&&(bool, bool);
2324 bool operator||(bool, bool); */
2326 case TRUTH_NOT_EXPR:
2327 build_builtin_candidate
2328 (candidates, fnname, boolean_type_node,
2329 NULL_TREE, args, argtypes, flags);
2332 case TRUTH_ORIF_EXPR:
2333 case TRUTH_ANDIF_EXPR:
2334 build_builtin_candidate
2335 (candidates, fnname, boolean_type_node,
2336 boolean_type_node, args, argtypes, flags);
2358 types[0] = types[1] = NULL_TREE;
2360 for (i = 0; i < 2; ++i)
2364 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2368 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2371 convs = lookup_conversions (argtypes[i],
2372 /*lookup_template_convs_p=*/false);
2374 if (code == COND_EXPR)
2376 if (real_lvalue_p (args[i]))
2377 types[i] = tree_cons
2378 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2380 types[i] = tree_cons
2381 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2387 for (; convs; convs = TREE_CHAIN (convs))
2389 type = TREE_TYPE (convs);
2392 && (TREE_CODE (type) != REFERENCE_TYPE
2393 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2396 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2397 types[i] = tree_cons (NULL_TREE, type, types[i]);
2399 type = non_reference (type);
2400 if (i != 0 || ! ref1)
2402 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2403 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2404 types[i] = tree_cons (NULL_TREE, type, types[i]);
2405 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2406 type = type_promotes_to (type);
2409 if (! value_member (type, types[i]))
2410 types[i] = tree_cons (NULL_TREE, type, types[i]);
2415 if (code == COND_EXPR && real_lvalue_p (args[i]))
2416 types[i] = tree_cons
2417 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2418 type = non_reference (argtypes[i]);
2419 if (i != 0 || ! ref1)
2421 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2422 if (enum_p && UNSCOPED_ENUM_P (type))
2423 types[i] = tree_cons (NULL_TREE, type, types[i]);
2424 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2425 type = type_promotes_to (type);
2427 types[i] = tree_cons (NULL_TREE, type, types[i]);
2431 /* Run through the possible parameter types of both arguments,
2432 creating candidates with those parameter types. */
2433 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2436 for (type = types[1]; type; type = TREE_CHAIN (type))
2437 add_builtin_candidate
2438 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2439 TREE_VALUE (type), args, argtypes, flags);
2441 add_builtin_candidate
2442 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2443 NULL_TREE, args, argtypes, flags);
2448 /* If TMPL can be successfully instantiated as indicated by
2449 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2451 TMPL is the template. EXPLICIT_TARGS are any explicit template
2452 arguments. ARGLIST is the arguments provided at the call-site.
2453 This does not change ARGLIST. The RETURN_TYPE is the desired type
2454 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2455 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2456 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2458 static struct z_candidate*
2459 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2460 tree ctype, tree explicit_targs, tree first_arg,
2461 const VEC(tree,gc) *arglist, tree return_type,
2462 tree access_path, tree conversion_path,
2463 int flags, tree obj, unification_kind_t strict)
2465 int ntparms = DECL_NTPARMS (tmpl);
2466 tree targs = make_tree_vec (ntparms);
2467 unsigned int len = VEC_length (tree, arglist);
2468 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2469 unsigned int skip_without_in_chrg = 0;
2470 tree first_arg_without_in_chrg = first_arg;
2471 tree *args_without_in_chrg;
2472 unsigned int nargs_without_in_chrg;
2473 unsigned int ia, ix;
2475 struct z_candidate *cand;
2479 /* We don't do deduction on the in-charge parameter, the VTT
2480 parameter or 'this'. */
2481 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2483 if (first_arg_without_in_chrg != NULL_TREE)
2484 first_arg_without_in_chrg = NULL_TREE;
2486 ++skip_without_in_chrg;
2489 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2490 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2491 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2493 if (first_arg_without_in_chrg != NULL_TREE)
2494 first_arg_without_in_chrg = NULL_TREE;
2496 ++skip_without_in_chrg;
2499 if (len < skip_without_in_chrg)
2502 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2503 + (len - skip_without_in_chrg));
2504 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2506 if (first_arg_without_in_chrg != NULL_TREE)
2508 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2511 for (ix = skip_without_in_chrg;
2512 VEC_iterate (tree, arglist, ix, arg);
2515 args_without_in_chrg[ia] = arg;
2518 gcc_assert (ia == nargs_without_in_chrg);
2520 i = fn_type_unification (tmpl, explicit_targs, targs,
2521 args_without_in_chrg,
2522 nargs_without_in_chrg,
2523 return_type, strict, flags);
2528 fn = instantiate_template (tmpl, targs, tf_none);
2529 if (fn == error_mark_node)
2534 A member function template is never instantiated to perform the
2535 copy of a class object to an object of its class type.
2537 It's a little unclear what this means; the standard explicitly
2538 does allow a template to be used to copy a class. For example,
2543 template <class T> A(const T&);
2546 void g () { A a (f ()); }
2548 the member template will be used to make the copy. The section
2549 quoted above appears in the paragraph that forbids constructors
2550 whose only parameter is (a possibly cv-qualified variant of) the
2551 class type, and a logical interpretation is that the intent was
2552 to forbid the instantiation of member templates which would then
2554 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2556 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2557 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2562 if (obj != NULL_TREE)
2563 /* Aha, this is a conversion function. */
2564 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2565 access_path, conversion_path);
2567 cand = add_function_candidate (candidates, fn, ctype,
2568 first_arg, arglist, access_path,
2569 conversion_path, flags);
2570 if (DECL_TI_TEMPLATE (fn) != tmpl)
2571 /* This situation can occur if a member template of a template
2572 class is specialized. Then, instantiate_template might return
2573 an instantiation of the specialization, in which case the
2574 DECL_TI_TEMPLATE field will point at the original
2575 specialization. For example:
2577 template <class T> struct S { template <class U> void f(U);
2578 template <> void f(int) {}; };
2582 Here, TMPL will be template <class U> S<double>::f(U).
2583 And, instantiate template will give us the specialization
2584 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2585 for this will point at template <class T> template <> S<T>::f(int),
2586 so that we can find the definition. For the purposes of
2587 overload resolution, however, we want the original TMPL. */
2588 cand->template_decl = build_template_info (tmpl, targs);
2590 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2596 static struct z_candidate *
2597 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2598 tree explicit_targs, tree first_arg,
2599 const VEC(tree,gc) *arglist, tree return_type,
2600 tree access_path, tree conversion_path, int flags,
2601 unification_kind_t strict)
2604 add_template_candidate_real (candidates, tmpl, ctype,
2605 explicit_targs, first_arg, arglist,
2606 return_type, access_path, conversion_path,
2607 flags, NULL_TREE, strict);
2611 static struct z_candidate *
2612 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2613 tree obj, tree first_arg,
2614 const VEC(tree,gc) *arglist,
2615 tree return_type, tree access_path,
2616 tree conversion_path)
2619 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2620 first_arg, arglist, return_type, access_path,
2621 conversion_path, 0, obj, DEDUCE_CONV);
2624 /* The CANDS are the set of candidates that were considered for
2625 overload resolution. Return the set of viable candidates. If none
2626 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2627 is true if a candidate should be considered viable only if it is
2630 static struct z_candidate*
2631 splice_viable (struct z_candidate *cands,
2635 struct z_candidate *viable;
2636 struct z_candidate **last_viable;
2637 struct z_candidate **cand;
2640 last_viable = &viable;
2641 *any_viable_p = false;
2646 struct z_candidate *c = *cand;
2647 if (strict_p ? c->viable == 1 : c->viable)
2652 last_viable = &c->next;
2653 *any_viable_p = true;
2659 return viable ? viable : cands;
2663 any_strictly_viable (struct z_candidate *cands)
2665 for (; cands; cands = cands->next)
2666 if (cands->viable == 1)
2671 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2672 words, it is about to become the "this" pointer for a member
2673 function call. Take the address of the object. */
2676 build_this (tree obj)
2678 /* In a template, we are only concerned about the type of the
2679 expression, so we can take a shortcut. */
2680 if (processing_template_decl)
2681 return build_address (obj);
2683 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2686 /* Returns true iff functions are equivalent. Equivalent functions are
2687 not '==' only if one is a function-local extern function or if
2688 both are extern "C". */
2691 equal_functions (tree fn1, tree fn2)
2693 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2694 || DECL_EXTERN_C_FUNCTION_P (fn1))
2695 return decls_match (fn1, fn2);
2699 /* Print information about one overload candidate CANDIDATE. MSGSTR
2700 is the text to print before the candidate itself.
2702 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2703 to have been run through gettext by the caller. This wart makes
2704 life simpler in print_z_candidates and for the translators. */
2707 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2709 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2711 if (candidate->num_convs == 3)
2712 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2713 candidate->convs[0]->type,
2714 candidate->convs[1]->type,
2715 candidate->convs[2]->type);
2716 else if (candidate->num_convs == 2)
2717 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2718 candidate->convs[0]->type,
2719 candidate->convs[1]->type);
2721 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2722 candidate->convs[0]->type);
2724 else if (TYPE_P (candidate->fn))
2725 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2726 else if (candidate->viable == -1)
2727 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2728 else if (DECL_DELETED_FN (candidate->fn))
2729 inform (input_location, "%s %+#D <deleted>", msgstr, candidate->fn);
2731 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2735 print_z_candidates (struct z_candidate *candidates)
2738 struct z_candidate *cand1;
2739 struct z_candidate **cand2;
2745 /* Remove deleted candidates. */
2747 for (cand2 = &cand1; *cand2; )
2749 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2750 && DECL_DELETED_FN ((*cand2)->fn))
2751 *cand2 = (*cand2)->next;
2753 cand2 = &(*cand2)->next;
2755 /* ...if there are any non-deleted ones. */
2759 /* There may be duplicates in the set of candidates. We put off
2760 checking this condition as long as possible, since we have no way
2761 to eliminate duplicates from a set of functions in less than n^2
2762 time. Now we are about to emit an error message, so it is more
2763 permissible to go slowly. */
2764 for (cand1 = candidates; cand1; cand1 = cand1->next)
2766 tree fn = cand1->fn;
2767 /* Skip builtin candidates and conversion functions. */
2768 if (TREE_CODE (fn) != FUNCTION_DECL)
2770 cand2 = &cand1->next;
2773 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2774 && equal_functions (fn, (*cand2)->fn))
2775 *cand2 = (*cand2)->next;
2777 cand2 = &(*cand2)->next;
2781 str = candidates->next ? _("candidates are:") : _("candidate is:");
2783 for (; candidates; candidates = candidates->next)
2785 print_z_candidate (spaces ? spaces : str, candidates);
2786 spaces = spaces ? spaces : get_spaces (str);
2791 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2792 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2793 the result of the conversion function to convert it to the final
2794 desired type. Merge the two sequences into a single sequence,
2795 and return the merged sequence. */
2798 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2802 gcc_assert (user_seq->kind == ck_user);
2804 /* Find the end of the second conversion sequence. */
2806 while ((*t)->kind != ck_identity)
2807 t = &((*t)->u.next);
2809 /* Replace the identity conversion with the user conversion
2813 /* The entire sequence is a user-conversion sequence. */
2814 std_seq->user_conv_p = true;
2819 /* Returns the best overload candidate to perform the requested
2820 conversion. This function is used for three the overloading situations
2821 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2822 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2823 per [dcl.init.ref], so we ignore temporary bindings. */
2825 static struct z_candidate *
2826 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2828 struct z_candidate *candidates, *cand;
2829 tree fromtype = TREE_TYPE (expr);
2830 tree ctors = NULL_TREE;
2831 tree conv_fns = NULL_TREE;
2832 conversion *conv = NULL;
2833 tree first_arg = NULL_TREE;
2834 VEC(tree,gc) *args = NULL;
2838 /* We represent conversion within a hierarchy using RVALUE_CONV and
2839 BASE_CONV, as specified by [over.best.ics]; these become plain
2840 constructor calls, as specified in [dcl.init]. */
2841 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2842 || !DERIVED_FROM_P (totype, fromtype));
2844 if (MAYBE_CLASS_TYPE_P (totype))
2845 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2847 if (MAYBE_CLASS_TYPE_P (fromtype))
2849 tree to_nonref = non_reference (totype);
2850 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2851 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2852 && DERIVED_FROM_P (to_nonref, fromtype)))
2854 /* [class.conv.fct] A conversion function is never used to
2855 convert a (possibly cv-qualified) object to the (possibly
2856 cv-qualified) same object type (or a reference to it), to a
2857 (possibly cv-qualified) base class of that type (or a
2858 reference to it)... */
2861 conv_fns = lookup_conversions (fromtype,
2862 /*lookup_template_convs_p=*/true);
2866 flags |= LOOKUP_NO_CONVERSION;
2868 /* It's OK to bind a temporary for converting constructor arguments, but
2869 not in converting the return value of a conversion operator. */
2870 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2871 flags &= ~LOOKUP_NO_TEMP_BIND;
2875 ctors = BASELINK_FUNCTIONS (ctors);
2877 first_arg = build_int_cst (build_pointer_type (totype), 0);
2878 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2879 && !TYPE_HAS_LIST_CTOR (totype))
2881 args = ctor_to_vec (expr);
2882 /* We still allow more conversions within an init-list. */
2883 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2884 /* But not for the copy ctor. */
2885 |LOOKUP_NO_COPY_CTOR_CONVERSION
2886 |LOOKUP_NO_NARROWING);
2889 args = make_tree_vector_single (expr);
2891 /* We should never try to call the abstract or base constructor
2893 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2894 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2896 for (; ctors; ctors = OVL_NEXT (ctors))
2898 tree ctor = OVL_CURRENT (ctors);
2899 if (DECL_NONCONVERTING_P (ctor)
2900 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2903 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2904 cand = add_template_candidate (&candidates, ctor, totype,
2905 NULL_TREE, first_arg, args, NULL_TREE,
2906 TYPE_BINFO (totype),
2907 TYPE_BINFO (totype),
2911 cand = add_function_candidate (&candidates, ctor, totype,
2912 first_arg, args, TYPE_BINFO (totype),
2913 TYPE_BINFO (totype),
2918 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2920 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2921 set, then this is copy-initialization. In that case, "The
2922 result of the call is then used to direct-initialize the
2923 object that is the destination of the copy-initialization."
2926 We represent this in the conversion sequence with an
2927 rvalue conversion, which means a constructor call. */
2928 if (TREE_CODE (totype) != REFERENCE_TYPE
2929 && !(convflags & LOOKUP_NO_TEMP_BIND))
2931 = build_conv (ck_rvalue, totype, cand->second_conv);
2936 first_arg = build_this (expr);
2938 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2941 tree conversion_path = TREE_PURPOSE (conv_fns);
2943 /* If we are called to convert to a reference type, we are trying to
2944 find an lvalue binding, so don't even consider temporaries. If
2945 we don't find an lvalue binding, the caller will try again to
2946 look for a temporary binding. */
2947 if (TREE_CODE (totype) == REFERENCE_TYPE)
2948 convflags |= LOOKUP_NO_TEMP_BIND;
2950 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2952 tree fn = OVL_CURRENT (fns);
2954 if (DECL_NONCONVERTING_P (fn)
2955 && (flags & LOOKUP_ONLYCONVERTING))
2958 /* [over.match.funcs] For conversion functions, the function
2959 is considered to be a member of the class of the implicit
2960 object argument for the purpose of defining the type of
2961 the implicit object parameter.
2963 So we pass fromtype as CTYPE to add_*_candidate. */
2965 if (TREE_CODE (fn) == TEMPLATE_DECL)
2966 cand = add_template_candidate (&candidates, fn, fromtype,
2968 first_arg, NULL, totype,
2969 TYPE_BINFO (fromtype),
2974 cand = add_function_candidate (&candidates, fn, fromtype,
2976 TYPE_BINFO (fromtype),
2983 = implicit_conversion (totype,
2984 TREE_TYPE (TREE_TYPE (cand->fn)),
2986 /*c_cast_p=*/false, convflags);
2988 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2989 copy-initialization. In that case, "The result of the
2990 call is then used to direct-initialize the object that is
2991 the destination of the copy-initialization." [dcl.init]
2993 We represent this in the conversion sequence with an
2994 rvalue conversion, which means a constructor call. But
2995 don't add a second rvalue conversion if there's already
2996 one there. Which there really shouldn't be, but it's
2997 harmless since we'd add it here anyway. */
2998 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2999 && !(convflags & LOOKUP_NO_TEMP_BIND))
3000 ics = build_conv (ck_rvalue, totype, ics);
3002 cand->second_conv = ics;
3006 else if (candidates->viable == 1 && ics->bad_p)
3012 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3016 cand = tourney (candidates);
3019 if (flags & LOOKUP_COMPLAIN)
3021 error ("conversion from %qT to %qT is ambiguous",
3023 print_z_candidates (candidates);
3026 cand = candidates; /* any one will do */
3027 cand->second_conv = build_ambiguous_conv (totype, expr);
3028 cand->second_conv->user_conv_p = true;
3029 if (!any_strictly_viable (candidates))
3030 cand->second_conv->bad_p = true;
3031 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3032 ambiguous conversion is no worse than another user-defined
3038 /* Build the user conversion sequence. */
3041 (DECL_CONSTRUCTOR_P (cand->fn)
3042 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3043 build_identity_conv (TREE_TYPE (expr), expr));
3046 /* Remember that this was a list-initialization. */
3047 if (flags & LOOKUP_NO_NARROWING)
3048 conv->check_narrowing = true;
3050 /* Combine it with the second conversion sequence. */
3051 cand->second_conv = merge_conversion_sequences (conv,
3054 if (cand->viable == -1)
3055 cand->second_conv->bad_p = true;
3061 build_user_type_conversion (tree totype, tree expr, int flags)
3063 struct z_candidate *cand
3064 = build_user_type_conversion_1 (totype, expr, flags);
3068 if (cand->second_conv->kind == ck_ambig)
3069 return error_mark_node;
3070 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3071 return convert_from_reference (expr);
3076 /* Do any initial processing on the arguments to a function call. */
3078 static VEC(tree,gc) *
3079 resolve_args (VEC(tree,gc) *args)
3084 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3086 if (error_operand_p (arg))
3088 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3090 error ("invalid use of void expression");
3093 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3099 /* Perform overload resolution on FN, which is called with the ARGS.
3101 Return the candidate function selected by overload resolution, or
3102 NULL if the event that overload resolution failed. In the case
3103 that overload resolution fails, *CANDIDATES will be the set of
3104 candidates considered, and ANY_VIABLE_P will be set to true or
3105 false to indicate whether or not any of the candidates were
3108 The ARGS should already have gone through RESOLVE_ARGS before this
3109 function is called. */
3111 static struct z_candidate *
3112 perform_overload_resolution (tree fn,
3113 const VEC(tree,gc) *args,
3114 struct z_candidate **candidates,
3117 struct z_candidate *cand;
3118 tree explicit_targs = NULL_TREE;
3119 int template_only = 0;
3122 *any_viable_p = true;
3125 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3126 || TREE_CODE (fn) == TEMPLATE_DECL
3127 || TREE_CODE (fn) == OVERLOAD
3128 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3130 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3132 explicit_targs = TREE_OPERAND (fn, 1);
3133 fn = TREE_OPERAND (fn, 0);
3137 /* Add the various candidate functions. */
3138 add_candidates (fn, args, explicit_targs, template_only,
3139 /*conversion_path=*/NULL_TREE,
3140 /*access_path=*/NULL_TREE,
3144 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3148 cand = tourney (*candidates);
3152 /* Return an expression for a call to FN (a namespace-scope function,
3153 or a static member function) with the ARGS. This may change
3157 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3158 tsubst_flags_t complain)
3160 struct z_candidate *candidates, *cand;
3165 if (args != NULL && *args != NULL)
3167 *args = resolve_args (*args);
3169 return error_mark_node;
3172 /* If this function was found without using argument dependent
3173 lookup, then we want to ignore any undeclared friend
3179 fn = remove_hidden_names (fn);
3182 if (complain & tf_error)
3183 error ("no matching function for call to %<%D(%A)%>",
3184 DECL_NAME (OVL_CURRENT (orig_fn)),
3185 build_tree_list_vec (*args));
3186 return error_mark_node;
3190 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3191 p = conversion_obstack_alloc (0);
3193 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3197 if (complain & tf_error)
3199 if (!any_viable_p && candidates && ! candidates->next)
3200 return cp_build_function_call_vec (candidates->fn, args, complain);
3201 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3202 fn = TREE_OPERAND (fn, 0);
3204 error ("no matching function for call to %<%D(%A)%>",
3205 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3207 error ("call of overloaded %<%D(%A)%> is ambiguous",
3208 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3210 print_z_candidates (candidates);
3212 result = error_mark_node;
3215 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3217 /* Free all the conversions we allocated. */
3218 obstack_free (&conversion_obstack, p);
3223 /* Build a call to a global operator new. FNNAME is the name of the
3224 operator (either "operator new" or "operator new[]") and ARGS are
3225 the arguments provided. This may change ARGS. *SIZE points to the
3226 total number of bytes required by the allocation, and is updated if
3227 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3228 be used. If this function determines that no cookie should be
3229 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3230 non-NULL, it will be set, upon return, to the allocation function
3234 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3235 tree *size, tree *cookie_size,
3239 struct z_candidate *candidates;
3240 struct z_candidate *cand;
3245 VEC_safe_insert (tree, gc, *args, 0, *size);
3246 *args = resolve_args (*args);
3248 return error_mark_node;
3254 If this lookup fails to find the name, or if the allocated type
3255 is not a class type, the allocation function's name is looked
3256 up in the global scope.
3258 we disregard block-scope declarations of "operator new". */
3259 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3261 /* Figure out what function is being called. */
3262 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3264 /* If no suitable function could be found, issue an error message
3269 error ("no matching function for call to %<%D(%A)%>",
3270 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3272 error ("call of overloaded %<%D(%A)%> is ambiguous",
3273 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3275 print_z_candidates (candidates);
3276 return error_mark_node;
3279 /* If a cookie is required, add some extra space. Whether
3280 or not a cookie is required cannot be determined until
3281 after we know which function was called. */
3284 bool use_cookie = true;
3285 if (!abi_version_at_least (2))
3287 /* In G++ 3.2, the check was implemented incorrectly; it
3288 looked at the placement expression, rather than the
3289 type of the function. */
3290 if (VEC_length (tree, *args) == 2
3291 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3299 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3300 /* Skip the size_t parameter. */
3301 arg_types = TREE_CHAIN (arg_types);
3302 /* Check the remaining parameters (if any). */
3304 && TREE_CHAIN (arg_types) == void_list_node
3305 && same_type_p (TREE_VALUE (arg_types),
3309 /* If we need a cookie, adjust the number of bytes allocated. */
3312 /* Update the total size. */
3313 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3314 /* Update the argument list to reflect the adjusted size. */
3315 VEC_replace (tree, *args, 0, *size);
3318 *cookie_size = NULL_TREE;
3321 /* Tell our caller which function we decided to call. */
3325 /* Build the CALL_EXPR. */
3326 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3329 /* Build a new call to operator(). This may change ARGS. */
3332 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3334 struct z_candidate *candidates = 0, *cand;
3335 tree fns, convs, first_mem_arg = NULL_TREE;
3336 tree type = TREE_TYPE (obj);
3338 tree result = NULL_TREE;
3341 if (error_operand_p (obj))
3342 return error_mark_node;
3344 obj = prep_operand (obj);
3346 if (TYPE_PTRMEMFUNC_P (type))
3348 if (complain & tf_error)
3349 /* It's no good looking for an overloaded operator() on a
3350 pointer-to-member-function. */
3351 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3352 return error_mark_node;
3355 if (TYPE_BINFO (type))
3357 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3358 if (fns == error_mark_node)
3359 return error_mark_node;
3364 if (args != NULL && *args != NULL)
3366 *args = resolve_args (*args);
3368 return error_mark_node;
3371 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3372 p = conversion_obstack_alloc (0);
3376 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3377 first_mem_arg = build_this (obj);
3379 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3381 tree fn = OVL_CURRENT (fns);
3383 if (TREE_CODE (fn) == TEMPLATE_DECL)
3384 add_template_candidate (&candidates, fn, base, NULL_TREE,
3385 first_mem_arg, *args, NULL_TREE,
3388 LOOKUP_NORMAL, DEDUCE_CALL);
3390 add_function_candidate
3391 (&candidates, fn, base, first_mem_arg, *args, TYPE_BINFO (type),
3392 TYPE_BINFO (type), LOOKUP_NORMAL);
3396 convs = lookup_conversions (type, /*lookup_template_convs_p=*/true);
3398 for (; convs; convs = TREE_CHAIN (convs))
3400 tree fns = TREE_VALUE (convs);
3401 tree totype = TREE_TYPE (convs);
3403 if ((TREE_CODE (totype) == POINTER_TYPE
3404 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3405 || (TREE_CODE (totype) == REFERENCE_TYPE
3406 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3407 || (TREE_CODE (totype) == REFERENCE_TYPE
3408 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3409 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3410 for (; fns; fns = OVL_NEXT (fns))
3412 tree fn = OVL_CURRENT (fns);
3414 if (DECL_NONCONVERTING_P (fn))
3417 if (TREE_CODE (fn) == TEMPLATE_DECL)
3418 add_template_conv_candidate
3419 (&candidates, fn, obj, NULL_TREE, *args, totype,
3420 /*access_path=*/NULL_TREE,
3421 /*conversion_path=*/NULL_TREE);
3423 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3424 *args, /*conversion_path=*/NULL_TREE,
3425 /*access_path=*/NULL_TREE);
3429 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3432 if (complain & tf_error)
3434 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3435 build_tree_list_vec (*args));
3436 print_z_candidates (candidates);
3438 result = error_mark_node;
3442 cand = tourney (candidates);
3445 if (complain & tf_error)
3447 error ("call of %<(%T) (%A)%> is ambiguous",
3448 TREE_TYPE (obj), build_tree_list_vec (*args));
3449 print_z_candidates (candidates);
3451 result = error_mark_node;
3453 /* Since cand->fn will be a type, not a function, for a conversion
3454 function, we must be careful not to unconditionally look at
3456 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3457 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3458 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3461 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3463 obj = convert_from_reference (obj);
3464 result = cp_build_function_call_vec (obj, args, complain);
3468 /* Free all the conversions we allocated. */
3469 obstack_free (&conversion_obstack, p);
3475 op_error (enum tree_code code, enum tree_code code2,
3476 tree arg1, tree arg2, tree arg3, bool match)
3480 if (code == MODIFY_EXPR)
3481 opname = assignment_operator_name_info[code2].name;
3483 opname = operator_name_info[code].name;
3489 error ("ambiguous overload for ternary %<operator?:%> "
3490 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3492 error ("no match for ternary %<operator?:%> "
3493 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3496 case POSTINCREMENT_EXPR:
3497 case POSTDECREMENT_EXPR:
3499 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
3500 opname, arg1, opname);
3502 error ("no match for %<operator%s%> in %<%E%s%>",
3503 opname, arg1, opname);
3508 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
3511 error ("no match for %<operator[]%> in %<%E[%E]%>",
3518 error ("ambiguous overload for %qs in %<%s %E%>",
3519 opname, opname, arg1);
3521 error ("no match for %qs in %<%s %E%>",
3522 opname, opname, arg1);
3528 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
3529 opname, arg1, opname, arg2);
3531 error ("no match for %<operator%s%> in %<%E %s %E%>",
3532 opname, arg1, opname, arg2);
3535 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
3536 opname, opname, arg1);
3538 error ("no match for %<operator%s%> in %<%s%E%>",
3539 opname, opname, arg1);
3544 /* Return the implicit conversion sequence that could be used to
3545 convert E1 to E2 in [expr.cond]. */
3548 conditional_conversion (tree e1, tree e2)
3550 tree t1 = non_reference (TREE_TYPE (e1));
3551 tree t2 = non_reference (TREE_TYPE (e2));
3557 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3558 implicitly converted (clause _conv_) to the type "reference to
3559 T2", subject to the constraint that in the conversion the
3560 reference must bind directly (_dcl.init.ref_) to E1. */
3561 if (real_lvalue_p (e2))
3563 conv = implicit_conversion (build_reference_type (t2),
3567 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3574 If E1 and E2 have class type, and the underlying class types are
3575 the same or one is a base class of the other: E1 can be converted
3576 to match E2 if the class of T2 is the same type as, or a base
3577 class of, the class of T1, and the cv-qualification of T2 is the
3578 same cv-qualification as, or a greater cv-qualification than, the
3579 cv-qualification of T1. If the conversion is applied, E1 is
3580 changed to an rvalue of type T2 that still refers to the original
3581 source class object (or the appropriate subobject thereof). */
3582 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3583 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3585 if (good_base && at_least_as_qualified_p (t2, t1))
3587 conv = build_identity_conv (t1, e1);
3588 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3589 TYPE_MAIN_VARIANT (t2)))
3590 conv = build_conv (ck_base, t2, conv);
3592 conv = build_conv (ck_rvalue, t2, conv);
3601 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3602 converted to the type that expression E2 would have if E2 were
3603 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3604 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3608 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3609 arguments to the conditional expression. */
3612 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3613 tsubst_flags_t complain)
3617 tree result = NULL_TREE;
3619 tree result_type = NULL_TREE;
3620 bool lvalue_p = true;
3621 struct z_candidate *candidates = 0;
3622 struct z_candidate *cand;
3625 /* As a G++ extension, the second argument to the conditional can be
3626 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3627 c'.) If the second operand is omitted, make sure it is
3628 calculated only once. */
3631 if (complain & tf_error)
3632 pedwarn (input_location, OPT_pedantic,
3633 "ISO C++ forbids omitting the middle term of a ?: expression");
3635 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3636 if (real_lvalue_p (arg1))
3637 arg2 = arg1 = stabilize_reference (arg1);
3639 arg2 = arg1 = save_expr (arg1);
3644 The first expression is implicitly converted to bool (clause
3646 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
3649 /* If something has already gone wrong, just pass that fact up the
3651 if (error_operand_p (arg1)
3652 || error_operand_p (arg2)
3653 || error_operand_p (arg3))
3654 return error_mark_node;
3658 If either the second or the third operand has type (possibly
3659 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3660 array-to-pointer (_conv.array_), and function-to-pointer
3661 (_conv.func_) standard conversions are performed on the second
3662 and third operands. */
3663 arg2_type = unlowered_expr_type (arg2);
3664 arg3_type = unlowered_expr_type (arg3);
3665 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3667 /* Do the conversions. We don't these for `void' type arguments
3668 since it can't have any effect and since decay_conversion
3669 does not handle that case gracefully. */
3670 if (!VOID_TYPE_P (arg2_type))
3671 arg2 = decay_conversion (arg2);
3672 if (!VOID_TYPE_P (arg3_type))
3673 arg3 = decay_conversion (arg3);
3674 arg2_type = TREE_TYPE (arg2);
3675 arg3_type = TREE_TYPE (arg3);
3679 One of the following shall hold:
3681 --The second or the third operand (but not both) is a
3682 throw-expression (_except.throw_); the result is of the
3683 type of the other and is an rvalue.
3685 --Both the second and the third operands have type void; the
3686 result is of type void and is an rvalue.
3688 We must avoid calling force_rvalue for expressions of type
3689 "void" because it will complain that their value is being
3691 if (TREE_CODE (arg2) == THROW_EXPR
3692 && TREE_CODE (arg3) != THROW_EXPR)
3694 if (!VOID_TYPE_P (arg3_type))
3695 arg3 = force_rvalue (arg3);
3696 arg3_type = TREE_TYPE (arg3);
3697 result_type = arg3_type;
3699 else if (TREE_CODE (arg2) != THROW_EXPR
3700 && TREE_CODE (arg3) == THROW_EXPR)
3702 if (!VOID_TYPE_P (arg2_type))
3703 arg2 = force_rvalue (arg2);
3704 arg2_type = TREE_TYPE (arg2);
3705 result_type = arg2_type;
3707 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3708 result_type = void_type_node;
3711 if (complain & tf_error)
3713 if (VOID_TYPE_P (arg2_type))
3714 error ("second operand to the conditional operator "
3715 "is of type %<void%>, "
3716 "but the third operand is neither a throw-expression "
3717 "nor of type %<void%>");
3719 error ("third operand to the conditional operator "
3720 "is of type %<void%>, "
3721 "but the second operand is neither a throw-expression "
3722 "nor of type %<void%>");
3724 return error_mark_node;
3728 goto valid_operands;
3732 Otherwise, if the second and third operand have different types,
3733 and either has (possibly cv-qualified) class type, an attempt is
3734 made to convert each of those operands to the type of the other. */
3735 else if (!same_type_p (arg2_type, arg3_type)
3736 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3741 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3742 p = conversion_obstack_alloc (0);
3744 conv2 = conditional_conversion (arg2, arg3);
3745 conv3 = conditional_conversion (arg3, arg2);
3749 If both can be converted, or one can be converted but the
3750 conversion is ambiguous, the program is ill-formed. If
3751 neither can be converted, the operands are left unchanged and
3752 further checking is performed as described below. If exactly
3753 one conversion is possible, that conversion is applied to the
3754 chosen operand and the converted operand is used in place of
3755 the original operand for the remainder of this section. */
3756 if ((conv2 && !conv2->bad_p
3757 && conv3 && !conv3->bad_p)
3758 || (conv2 && conv2->kind == ck_ambig)
3759 || (conv3 && conv3->kind == ck_ambig))
3761 error ("operands to ?: have different types %qT and %qT",
3762 arg2_type, arg3_type);
3763 result = error_mark_node;
3765 else if (conv2 && (!conv2->bad_p || !conv3))
3767 arg2 = convert_like (conv2, arg2, complain);
3768 arg2 = convert_from_reference (arg2);
3769 arg2_type = TREE_TYPE (arg2);
3770 /* Even if CONV2 is a valid conversion, the result of the
3771 conversion may be invalid. For example, if ARG3 has type
3772 "volatile X", and X does not have a copy constructor
3773 accepting a "volatile X&", then even if ARG2 can be
3774 converted to X, the conversion will fail. */
3775 if (error_operand_p (arg2))
3776 result = error_mark_node;
3778 else if (conv3 && (!conv3->bad_p || !conv2))
3780 arg3 = convert_like (conv3, arg3, complain);
3781 arg3 = convert_from_reference (arg3);
3782 arg3_type = TREE_TYPE (arg3);
3783 if (error_operand_p (arg3))
3784 result = error_mark_node;
3787 /* Free all the conversions we allocated. */
3788 obstack_free (&conversion_obstack, p);
3793 /* If, after the conversion, both operands have class type,
3794 treat the cv-qualification of both operands as if it were the
3795 union of the cv-qualification of the operands.
3797 The standard is not clear about what to do in this
3798 circumstance. For example, if the first operand has type
3799 "const X" and the second operand has a user-defined
3800 conversion to "volatile X", what is the type of the second
3801 operand after this step? Making it be "const X" (matching
3802 the first operand) seems wrong, as that discards the
3803 qualification without actually performing a copy. Leaving it
3804 as "volatile X" seems wrong as that will result in the
3805 conditional expression failing altogether, even though,
3806 according to this step, the one operand could be converted to
3807 the type of the other. */
3808 if ((conv2 || conv3)
3809 && CLASS_TYPE_P (arg2_type)
3810 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3811 arg2_type = arg3_type =
3812 cp_build_qualified_type (arg2_type,
3813 TYPE_QUALS (arg2_type)
3814 | TYPE_QUALS (arg3_type));
3819 If the second and third operands are lvalues and have the same
3820 type, the result is of that type and is an lvalue. */
3821 if (real_lvalue_p (arg2)
3822 && real_lvalue_p (arg3)
3823 && same_type_p (arg2_type, arg3_type))
3825 result_type = arg2_type;
3826 goto valid_operands;
3831 Otherwise, the result is an rvalue. If the second and third
3832 operand do not have the same type, and either has (possibly
3833 cv-qualified) class type, overload resolution is used to
3834 determine the conversions (if any) to be applied to the operands
3835 (_over.match.oper_, _over.built_). */
3837 if (!same_type_p (arg2_type, arg3_type)
3838 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3844 /* Rearrange the arguments so that add_builtin_candidate only has
3845 to know about two args. In build_builtin_candidate, the
3846 arguments are unscrambled. */
3850 add_builtin_candidates (&candidates,
3853 ansi_opname (COND_EXPR),
3859 If the overload resolution fails, the program is
3861 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3864 if (complain & tf_error)
3866 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3867 print_z_candidates (candidates);
3869 return error_mark_node;
3871 cand = tourney (candidates);
3874 if (complain & tf_error)
3876 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3877 print_z_candidates (candidates);
3879 return error_mark_node;
3884 Otherwise, the conversions thus determined are applied, and
3885 the converted operands are used in place of the original
3886 operands for the remainder of this section. */
3887 conv = cand->convs[0];
3888 arg1 = convert_like (conv, arg1, complain);
3889 conv = cand->convs[1];
3890 arg2 = convert_like (conv, arg2, complain);
3891 arg2_type = TREE_TYPE (arg2);
3892 conv = cand->convs[2];
3893 arg3 = convert_like (conv, arg3, complain);
3894 arg3_type = TREE_TYPE (arg3);
3899 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3900 and function-to-pointer (_conv.func_) standard conversions are
3901 performed on the second and third operands.
3903 We need to force the lvalue-to-rvalue conversion here for class types,
3904 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3905 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3908 arg2 = force_rvalue (arg2);
3909 if (!CLASS_TYPE_P (arg2_type))
3910 arg2_type = TREE_TYPE (arg2);
3912 arg3 = force_rvalue (arg3);
3913 if (!CLASS_TYPE_P (arg3_type))
3914 arg3_type = TREE_TYPE (arg3);
3916 if (arg2 == error_mark_node || arg3 == error_mark_node)
3917 return error_mark_node;
3921 After those conversions, one of the following shall hold:
3923 --The second and third operands have the same type; the result is of
3925 if (same_type_p (arg2_type, arg3_type))
3926 result_type = arg2_type;
3929 --The second and third operands have arithmetic or enumeration
3930 type; the usual arithmetic conversions are performed to bring
3931 them to a common type, and the result is of that type. */
3932 else if ((ARITHMETIC_TYPE_P (arg2_type)
3933 || UNSCOPED_ENUM_P (arg2_type))
3934 && (ARITHMETIC_TYPE_P (arg3_type)
3935 || UNSCOPED_ENUM_P (arg3_type)))
3937 /* In this case, there is always a common type. */
3938 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3941 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3942 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3944 if (complain & tf_warning)
3946 "enumeral mismatch in conditional expression: %qT vs %qT",
3947 arg2_type, arg3_type);
3949 else if (extra_warnings
3950 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3951 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3952 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3953 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3955 if (complain & tf_warning)
3957 "enumeral and non-enumeral type in conditional expression");
3960 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3961 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3965 --The second and third operands have pointer type, or one has
3966 pointer type and the other is a null pointer constant; pointer
3967 conversions (_conv.ptr_) and qualification conversions
3968 (_conv.qual_) are performed to bring them to their composite
3969 pointer type (_expr.rel_). The result is of the composite
3972 --The second and third operands have pointer to member type, or
3973 one has pointer to member type and the other is a null pointer
3974 constant; pointer to member conversions (_conv.mem_) and
3975 qualification conversions (_conv.qual_) are performed to bring
3976 them to a common type, whose cv-qualification shall match the
3977 cv-qualification of either the second or the third operand.
3978 The result is of the common type. */
3979 else if ((null_ptr_cst_p (arg2)
3980 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3981 || (null_ptr_cst_p (arg3)
3982 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3983 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3984 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3985 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3987 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3988 arg3, CPO_CONDITIONAL_EXPR,
3990 if (result_type == error_mark_node)
3991 return error_mark_node;
3992 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3993 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3998 if (complain & tf_error)
3999 error ("operands to ?: have different types %qT and %qT",
4000 arg2_type, arg3_type);
4001 return error_mark_node;
4005 result_save = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4006 result = fold_if_not_in_template (result_save);
4008 if (cp_unevaluated_operand && TREE_CODE (result) == CALL_EXPR)
4009 /* Avoid folding to a CALL_EXPR within decltype (c++/42013). */
4010 result = result_save;
4012 /* We can't use result_type below, as fold might have returned a
4017 /* Expand both sides into the same slot, hopefully the target of
4018 the ?: expression. We used to check for TARGET_EXPRs here,
4019 but now we sometimes wrap them in NOP_EXPRs so the test would
4021 if (CLASS_TYPE_P (TREE_TYPE (result)))
4022 result = get_target_expr (result);
4023 /* If this expression is an rvalue, but might be mistaken for an
4024 lvalue, we must add a NON_LVALUE_EXPR. */
4025 result = rvalue (result);
4031 /* OPERAND is an operand to an expression. Perform necessary steps
4032 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4036 prep_operand (tree operand)
4040 if (CLASS_TYPE_P (TREE_TYPE (operand))
4041 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4042 /* Make sure the template type is instantiated now. */
4043 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4049 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4050 OVERLOAD) to the CANDIDATES, returning an updated list of
4051 CANDIDATES. The ARGS are the arguments provided to the call,
4052 without any implicit object parameter. This may change ARGS. The
4053 EXPLICIT_TARGS are explicit template arguments provided.
4054 TEMPLATE_ONLY is true if only template functions should be
4055 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4056 add_function_candidate. */
4059 add_candidates (tree fns, const VEC(tree,gc) *args,
4060 tree explicit_targs, bool template_only,
4061 tree conversion_path, tree access_path,
4063 struct z_candidate **candidates)
4066 VEC(tree,gc) *non_static_args;
4069 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4070 /* Delay creating the implicit this parameter until it is needed. */
4071 non_static_args = NULL;
4072 first_arg = NULL_TREE;
4078 const VEC(tree,gc) *fn_args;
4080 fn = OVL_CURRENT (fns);
4081 /* Figure out which set of arguments to use. */
4082 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4084 /* If this function is a non-static member, prepend the implicit
4085 object parameter. */
4086 if (non_static_args == NULL)
4091 non_static_args = VEC_alloc (tree, gc,
4092 VEC_length (tree, args) - 1);
4093 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4094 VEC_quick_push (tree, non_static_args, arg);
4096 if (first_arg == NULL_TREE)
4097 first_arg = build_this (VEC_index (tree, args, 0));
4098 fn_first_arg = first_arg;
4099 fn_args = non_static_args;
4103 /* Otherwise, just use the list of arguments provided. */
4104 fn_first_arg = NULL_TREE;
4108 if (TREE_CODE (fn) == TEMPLATE_DECL)
4109 add_template_candidate (candidates,
4120 else if (!template_only)
4121 add_function_candidate (candidates,
4129 fns = OVL_NEXT (fns);
4133 /* Even unsigned enum types promote to signed int. We don't want to
4134 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4135 original argument and ARG is the argument after any conversions
4136 have been applied. We set TREE_NO_WARNING if we have added a cast
4137 from an unsigned enum type to a signed integer type. */
4140 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4142 if (orig_arg != NULL_TREE
4145 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4146 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4147 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4148 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4149 TREE_NO_WARNING (arg) = 1;
4153 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4154 bool *overloaded_p, tsubst_flags_t complain)
4156 tree orig_arg1 = arg1;
4157 tree orig_arg2 = arg2;
4158 tree orig_arg3 = arg3;
4159 struct z_candidate *candidates = 0, *cand;
4160 VEC(tree,gc) *arglist;
4163 tree result = NULL_TREE;
4164 bool result_valid_p = false;
4165 enum tree_code code2 = NOP_EXPR;
4166 enum tree_code code_orig_arg1 = ERROR_MARK;
4167 enum tree_code code_orig_arg2 = ERROR_MARK;
4173 if (error_operand_p (arg1)
4174 || error_operand_p (arg2)
4175 || error_operand_p (arg3))
4176 return error_mark_node;
4178 if (code == MODIFY_EXPR)
4180 code2 = TREE_CODE (arg3);
4182 fnname = ansi_assopname (code2);
4185 fnname = ansi_opname (code);
4187 arg1 = prep_operand (arg1);
4193 case VEC_DELETE_EXPR:
4195 /* Use build_op_new_call and build_op_delete_call instead. */
4199 /* Use build_op_call instead. */
4202 case TRUTH_ORIF_EXPR:
4203 case TRUTH_ANDIF_EXPR:
4204 case TRUTH_AND_EXPR:
4206 /* These are saved for the sake of warn_logical_operator. */
4207 code_orig_arg1 = TREE_CODE (arg1);
4208 code_orig_arg2 = TREE_CODE (arg2);
4214 arg2 = prep_operand (arg2);
4215 arg3 = prep_operand (arg3);
4217 if (code == COND_EXPR)
4218 /* Use build_conditional_expr instead. */
4220 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4221 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4224 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4225 arg2 = integer_zero_node;
4227 arglist = VEC_alloc (tree, gc, 3);
4228 VEC_quick_push (tree, arglist, arg1);
4229 if (arg2 != NULL_TREE)
4230 VEC_quick_push (tree, arglist, arg2);
4231 if (arg3 != NULL_TREE)
4232 VEC_quick_push (tree, arglist, arg3);
4234 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4235 p = conversion_obstack_alloc (0);
4237 /* Add namespace-scope operators to the list of functions to
4239 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4240 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4241 flags, &candidates);
4242 /* Add class-member operators to the candidate set. */
4243 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4247 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4248 if (fns == error_mark_node)
4250 result = error_mark_node;
4251 goto user_defined_result_ready;
4254 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4256 BASELINK_BINFO (fns),
4257 TYPE_BINFO (TREE_TYPE (arg1)),
4258 flags, &candidates);
4263 args[2] = NULL_TREE;
4265 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4271 /* For these, the built-in candidates set is empty
4272 [over.match.oper]/3. We don't want non-strict matches
4273 because exact matches are always possible with built-in
4274 operators. The built-in candidate set for COMPONENT_REF
4275 would be empty too, but since there are no such built-in
4276 operators, we accept non-strict matches for them. */
4281 strict_p = pedantic;
4285 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4290 case POSTINCREMENT_EXPR:
4291 case POSTDECREMENT_EXPR:
4292 /* Don't try anything fancy if we're not allowed to produce
4294 if (!(complain & tf_error))
4295 return error_mark_node;
4297 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4298 distinguish between prefix and postfix ++ and
4299 operator++() was used for both, so we allow this with
4301 if (flags & LOOKUP_COMPLAIN)
4303 const char *msg = (flag_permissive)
4304 ? G_("no %<%D(int)%> declared for postfix %qs,"
4305 " trying prefix operator instead")
4306 : G_("no %<%D(int)%> declared for postfix %qs");
4307 permerror (input_location, msg, fnname,
4308 operator_name_info[code].name);
4311 if (!flag_permissive)
4312 return error_mark_node;
4314 if (code == POSTINCREMENT_EXPR)
4315 code = PREINCREMENT_EXPR;
4317 code = PREDECREMENT_EXPR;
4318 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4319 overloaded_p, complain);
4322 /* The caller will deal with these. */
4327 result_valid_p = true;
4331 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4333 /* If one of the arguments of the operator represents
4334 an invalid use of member function pointer, try to report
4335 a meaningful error ... */
4336 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4337 || invalid_nonstatic_memfn_p (arg2, tf_error)
4338 || invalid_nonstatic_memfn_p (arg3, tf_error))
4339 /* We displayed the error message. */;
4342 /* ... Otherwise, report the more generic
4343 "no matching operator found" error */
4344 op_error (code, code2, arg1, arg2, arg3, FALSE);
4345 print_z_candidates (candidates);
4348 result = error_mark_node;
4354 cand = tourney (candidates);
4357 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4359 op_error (code, code2, arg1, arg2, arg3, TRUE);
4360 print_z_candidates (candidates);
4362 result = error_mark_node;
4364 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4367 *overloaded_p = true;
4369 if (resolve_args (arglist) == NULL)
4370 result = error_mark_node;
4372 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4376 /* Give any warnings we noticed during overload resolution. */
4377 if (cand->warnings && (complain & tf_warning))
4379 struct candidate_warning *w;
4380 for (w = cand->warnings; w; w = w->next)
4381 joust (cand, w->loser, 1);
4384 /* Check for comparison of different enum types. */
4393 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4394 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4395 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4396 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4397 && (complain & tf_warning))
4399 warning (OPT_Wenum_compare,
4400 "comparison between %q#T and %q#T",
4401 TREE_TYPE (arg1), TREE_TYPE (arg2));
4408 /* We need to strip any leading REF_BIND so that bitfields
4409 don't cause errors. This should not remove any important
4410 conversions, because builtins don't apply to class
4411 objects directly. */
4412 conv = cand->convs[0];
4413 if (conv->kind == ck_ref_bind)
4414 conv = conv->u.next;
4415 arg1 = convert_like (conv, arg1, complain);
4419 /* We need to call warn_logical_operator before
4420 converting arg2 to a boolean_type. */
4421 if (complain & tf_warning)
4422 warn_logical_operator (input_location, code, boolean_type_node,
4423 code_orig_arg1, arg1,
4424 code_orig_arg2, arg2);
4426 conv = cand->convs[1];
4427 if (conv->kind == ck_ref_bind)
4428 conv = conv->u.next;
4429 arg2 = convert_like (conv, arg2, complain);
4433 conv = cand->convs[2];
4434 if (conv->kind == ck_ref_bind)
4435 conv = conv->u.next;
4436 arg3 = convert_like (conv, arg3, complain);
4442 user_defined_result_ready:
4444 /* Free all the conversions we allocated. */
4445 obstack_free (&conversion_obstack, p);
4447 if (result || result_valid_p)
4451 avoid_sign_compare_warnings (orig_arg1, arg1);
4452 avoid_sign_compare_warnings (orig_arg2, arg2);
4453 avoid_sign_compare_warnings (orig_arg3, arg3);
4458 return cp_build_modify_expr (arg1, code2, arg2, complain);
4461 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
4463 case TRUTH_ANDIF_EXPR:
4464 case TRUTH_ORIF_EXPR:
4465 case TRUTH_AND_EXPR:
4467 warn_logical_operator (input_location, code, boolean_type_node,
4468 code_orig_arg1, arg1, code_orig_arg2, arg2);
4473 case TRUNC_DIV_EXPR:
4484 case TRUNC_MOD_EXPR:
4488 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4490 case UNARY_PLUS_EXPR:
4493 case TRUTH_NOT_EXPR:
4494 case PREINCREMENT_EXPR:
4495 case POSTINCREMENT_EXPR:
4496 case PREDECREMENT_EXPR:
4497 case POSTDECREMENT_EXPR:
4500 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4503 return build_array_ref (input_location, arg1, arg2);
4506 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
4510 /* The caller will deal with these. */
4522 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
4523 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
4526 non_placement_deallocation_fn_p (tree t)
4528 /* A template instance is never a usual deallocation function,
4529 regardless of its signature. */
4530 if (TREE_CODE (t) == TEMPLATE_DECL
4531 || primary_template_instantiation_p (t))
4534 /* If a class T has a member deallocation function named operator delete
4535 with exactly one parameter, then that function is a usual
4536 (non-placement) deallocation function. If class T does not declare
4537 such an operator delete but does declare a member deallocation
4538 function named operator delete with exactly two parameters, the second
4539 of which has type std::size_t (18.2), then this function is a usual
4540 deallocation function. */
4541 t = FUNCTION_ARG_CHAIN (t);
4542 if (t == void_list_node
4543 || (t && same_type_p (TREE_VALUE (t), size_type_node)
4544 && TREE_CHAIN (t) == void_list_node))
4549 /* Build a call to operator delete. This has to be handled very specially,
4550 because the restrictions on what signatures match are different from all
4551 other call instances. For a normal delete, only a delete taking (void *)
4552 or (void *, size_t) is accepted. For a placement delete, only an exact
4553 match with the placement new is accepted.
4555 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4556 ADDR is the pointer to be deleted.
4557 SIZE is the size of the memory block to be deleted.
4558 GLOBAL_P is true if the delete-expression should not consider
4559 class-specific delete operators.
4560 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4562 If this call to "operator delete" is being generated as part to
4563 deallocate memory allocated via a new-expression (as per [expr.new]
4564 which requires that if the initialization throws an exception then
4565 we call a deallocation function), then ALLOC_FN is the allocation
4569 build_op_delete_call (enum tree_code code, tree addr, tree size,
4570 bool global_p, tree placement,
4573 tree fn = NULL_TREE;
4574 tree fns, fnname, type, t;
4576 if (addr == error_mark_node)
4577 return error_mark_node;
4579 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4581 fnname = ansi_opname (code);
4583 if (CLASS_TYPE_P (type)
4584 && COMPLETE_TYPE_P (complete_type (type))
4588 If the result of the lookup is ambiguous or inaccessible, or if
4589 the lookup selects a placement deallocation function, the
4590 program is ill-formed.
4592 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4594 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4595 if (fns == error_mark_node)
4596 return error_mark_node;
4601 if (fns == NULL_TREE)
4602 fns = lookup_name_nonclass (fnname);
4604 /* Strip const and volatile from addr. */
4605 addr = cp_convert (ptr_type_node, addr);
4609 /* "A declaration of a placement deallocation function matches the
4610 declaration of a placement allocation function if it has the same
4611 number of parameters and, after parameter transformations (8.3.5),
4612 all parameter types except the first are identical."
4614 So we build up the function type we want and ask instantiate_type
4615 to get it for us. */
4616 t = FUNCTION_ARG_CHAIN (alloc_fn);
4617 t = tree_cons (NULL_TREE, ptr_type_node, t);
4618 t = build_function_type (void_type_node, t);
4620 fn = instantiate_type (t, fns, tf_none);
4621 if (fn == error_mark_node)
4624 if (BASELINK_P (fn))
4625 fn = BASELINK_FUNCTIONS (fn);
4627 /* "If the lookup finds the two-parameter form of a usual deallocation
4628 function (3.7.4.2) and that function, considered as a placement
4629 deallocation function, would have been selected as a match for the
4630 allocation function, the program is ill-formed." */
4631 if (non_placement_deallocation_fn_p (fn))
4633 /* But if the class has an operator delete (void *), then that is
4634 the usual deallocation function, so we shouldn't complain
4635 about using the operator delete (void *, size_t). */
4636 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4637 t; t = OVL_NEXT (t))
4639 tree elt = OVL_CURRENT (t);
4640 if (non_placement_deallocation_fn_p (elt)
4641 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
4644 permerror (0, "non-placement deallocation function %q+D", fn);
4645 permerror (input_location, "selected for placement delete");
4650 /* "Any non-placement deallocation function matches a non-placement
4651 allocation function. If the lookup finds a single matching
4652 deallocation function, that function will be called; otherwise, no
4653 deallocation function will be called." */
4654 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4655 t; t = OVL_NEXT (t))
4657 tree elt = OVL_CURRENT (t);
4658 if (non_placement_deallocation_fn_p (elt))
4661 /* "If a class T has a member deallocation function named
4662 operator delete with exactly one parameter, then that
4663 function is a usual (non-placement) deallocation
4664 function. If class T does not declare such an operator
4665 delete but does declare a member deallocation function named
4666 operator delete with exactly two parameters, the second of
4667 which has type std::size_t (18.2), then this function is a
4668 usual deallocation function."
4670 So (void*) beats (void*, size_t). */
4671 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4676 /* If we have a matching function, call it. */
4679 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
4681 /* If the FN is a member function, make sure that it is
4683 if (BASELINK_P (fns))
4684 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
4686 /* Core issue 901: It's ok to new a type with deleted delete. */
4687 if (DECL_DELETED_FN (fn) && alloc_fn)
4692 /* The placement args might not be suitable for overload
4693 resolution at this point, so build the call directly. */
4694 int nargs = call_expr_nargs (placement);
4695 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4698 for (i = 1; i < nargs; i++)
4699 argarray[i] = CALL_EXPR_ARG (placement, i);
4701 return build_cxx_call (fn, nargs, argarray);
4706 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4707 VEC_quick_push (tree, args, addr);
4708 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
4709 VEC_quick_push (tree, args, size);
4710 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4711 VEC_free (tree, gc, args);
4718 If no unambiguous matching deallocation function can be found,
4719 propagating the exception does not cause the object's memory to
4724 warning (0, "no corresponding deallocation function for %qD",
4729 error ("no suitable %<operator %s%> for %qT",
4730 operator_name_info[(int)code].name, type);
4731 return error_mark_node;
4734 /* If the current scope isn't allowed to access DECL along
4735 BASETYPE_PATH, give an error. The most derived class in
4736 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4737 the declaration to use in the error diagnostic. */
4740 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4742 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4744 if (!accessible_p (basetype_path, decl, true))
4746 if (TREE_PRIVATE (decl))
4747 error ("%q+#D is private", diag_decl);
4748 else if (TREE_PROTECTED (decl))
4749 error ("%q+#D is protected", diag_decl);
4751 error ("%q+#D is inaccessible", diag_decl);
4752 error ("within this context");
4759 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4760 bitwise or of LOOKUP_* values. If any errors are warnings are
4761 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4762 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4766 build_temp (tree expr, tree type, int flags,
4767 diagnostic_t *diagnostic_kind)
4772 savew = warningcount, savee = errorcount;
4773 args = make_tree_vector_single (expr);
4774 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4775 &args, type, flags, tf_warning_or_error);
4776 release_tree_vector (args);
4777 if (warningcount > savew)
4778 *diagnostic_kind = DK_WARNING;
4779 else if (errorcount > savee)
4780 *diagnostic_kind = DK_ERROR;
4782 *diagnostic_kind = DK_UNSPECIFIED;
4786 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4787 EXPR is implicitly converted to type TOTYPE.
4788 FN and ARGNUM are used for diagnostics. */
4791 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4793 tree t = non_reference (totype);
4795 /* Issue warnings about peculiar, but valid, uses of NULL. */
4796 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4799 warning_at (input_location, OPT_Wconversion_null,
4800 "passing NULL to non-pointer argument %P of %qD",
4803 warning_at (input_location, OPT_Wconversion_null,
4804 "converting to non-pointer type %qT from NULL", t);
4807 /* Issue warnings if "false" is converted to a NULL pointer */
4808 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4809 warning_at (input_location, OPT_Wconversion_null,
4810 "converting %<false%> to pointer type for argument %P of %qD",
4814 /* Perform the conversions in CONVS on the expression EXPR. FN and
4815 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4816 indicates the `this' argument of a method. INNER is nonzero when
4817 being called to continue a conversion chain. It is negative when a
4818 reference binding will be applied, positive otherwise. If
4819 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4820 conversions will be emitted if appropriate. If C_CAST_P is true,
4821 this conversion is coming from a C-style cast; in that case,
4822 conversions to inaccessible bases are permitted. */
4825 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4826 int inner, bool issue_conversion_warnings,
4827 bool c_cast_p, tsubst_flags_t complain)
4829 tree totype = convs->type;
4830 diagnostic_t diag_kind;
4834 && convs->kind != ck_user
4835 && convs->kind != ck_list
4836 && convs->kind != ck_ambig
4837 && convs->kind != ck_ref_bind
4838 && convs->kind != ck_rvalue
4839 && convs->kind != ck_base)
4841 conversion *t = convs;
4843 /* Give a helpful error if this is bad because of excess braces. */
4844 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4845 && SCALAR_TYPE_P (totype)
4846 && CONSTRUCTOR_NELTS (expr) > 0
4847 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4848 permerror (input_location, "too many braces around initializer for %qT", totype);
4850 for (; t; t = convs->u.next)
4852 if (t->kind == ck_user || !t->bad_p)
4854 expr = convert_like_real (t, expr, fn, argnum, 1,
4855 /*issue_conversion_warnings=*/false,
4860 else if (t->kind == ck_ambig)
4861 return convert_like_real (t, expr, fn, argnum, 1,
4862 /*issue_conversion_warnings=*/false,
4865 else if (t->kind == ck_identity)
4868 if (complain & tf_error)
4870 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4872 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4875 return error_mark_node;
4877 return cp_convert (totype, expr);
4880 if (issue_conversion_warnings && (complain & tf_warning))
4881 conversion_null_warnings (totype, expr, fn, argnum);
4883 switch (convs->kind)
4887 struct z_candidate *cand = convs->cand;
4888 tree convfn = cand->fn;
4891 /* When converting from an init list we consider explicit
4892 constructors, but actually trying to call one is an error. */
4893 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4895 if (complain & tf_error)
4896 error ("converting to %qT from initializer list would use "
4897 "explicit constructor %qD", totype, convfn);
4899 return error_mark_node;
4902 /* Set user_conv_p on the argument conversions, so rvalue/base
4903 handling knows not to allow any more UDCs. */
4904 for (i = 0; i < cand->num_convs; ++i)
4905 cand->convs[i]->user_conv_p = true;
4907 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4909 /* If this is a constructor or a function returning an aggr type,
4910 we need to build up a TARGET_EXPR. */
4911 if (DECL_CONSTRUCTOR_P (convfn))
4913 expr = build_cplus_new (totype, expr);
4915 /* Remember that this was list-initialization. */
4916 if (convs->check_narrowing)
4917 TARGET_EXPR_LIST_INIT_P (expr) = true;
4923 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4925 int nelts = CONSTRUCTOR_NELTS (expr);
4927 expr = integer_zero_node;
4928 else if (nelts == 1)
4929 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4934 if (type_unknown_p (expr))
4935 expr = instantiate_type (totype, expr, complain);
4936 /* Convert a constant to its underlying value, unless we are
4937 about to bind it to a reference, in which case we need to
4938 leave it as an lvalue. */
4941 expr = decl_constant_value (expr);
4942 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4943 /* If __null has been converted to an integer type, we do not
4944 want to warn about uses of EXPR as an integer, rather than
4946 expr = build_int_cst (totype, 0);
4950 /* Call build_user_type_conversion again for the error. */
4951 return build_user_type_conversion
4952 (totype, convs->u.expr, LOOKUP_NORMAL);
4956 /* Conversion to std::initializer_list<T>. */
4957 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4958 tree new_ctor = build_constructor (init_list_type_node, NULL);
4959 unsigned len = CONSTRUCTOR_NELTS (expr);
4961 VEC(tree,gc) *parms;
4964 /* Convert all the elements. */
4965 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4967 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4968 1, false, false, complain);
4969 if (sub == error_mark_node)
4971 check_narrowing (TREE_TYPE (sub), val);
4972 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4974 /* Build up the array. */
4975 elttype = cp_build_qualified_type
4976 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4977 array = build_array_of_n_type (elttype, len);
4978 array = finish_compound_literal (array, new_ctor);
4980 parms = make_tree_vector ();
4981 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4982 VEC_safe_push (tree, gc, parms, size_int (len));
4983 /* Call the private constructor. */
4984 push_deferring_access_checks (dk_no_check);
4985 new_ctor = build_special_member_call
4986 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4987 release_tree_vector (parms);
4988 pop_deferring_access_checks ();
4989 return build_cplus_new (totype, new_ctor);
4993 return get_target_expr (digest_init (totype, expr));
4999 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5000 convs->kind == ck_ref_bind ? -1 : 1,
5001 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5004 if (expr == error_mark_node)
5005 return error_mark_node;
5007 switch (convs->kind)
5010 expr = decay_conversion (expr);
5011 if (! MAYBE_CLASS_TYPE_P (totype))
5013 /* Else fall through. */
5015 if (convs->kind == ck_base && !convs->need_temporary_p)
5017 /* We are going to bind a reference directly to a base-class
5018 subobject of EXPR. */
5019 /* Build an expression for `*((base*) &expr)'. */
5020 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5021 expr = convert_to_base (expr, build_pointer_type (totype),
5022 !c_cast_p, /*nonnull=*/true);
5023 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5027 /* Copy-initialization where the cv-unqualified version of the source
5028 type is the same class as, or a derived class of, the class of the
5029 destination [is treated as direct-initialization]. [dcl.init] */
5030 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5031 if (convs->user_conv_p)
5032 /* This conversion is being done in the context of a user-defined
5033 conversion (i.e. the second step of copy-initialization), so
5034 don't allow any more. */
5035 flags |= LOOKUP_NO_CONVERSION;
5036 expr = build_temp (expr, totype, flags, &diag_kind);
5037 if (diag_kind && fn)
5039 if ((complain & tf_error))
5040 emit_diagnostic (diag_kind, input_location, 0,
5041 " initializing argument %P of %qD", argnum, fn);
5042 else if (diag_kind == DK_ERROR)
5043 return error_mark_node;
5045 return build_cplus_new (totype, expr);
5049 tree ref_type = totype;
5051 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5052 && real_lvalue_p (expr))
5054 if (complain & tf_error)
5056 error ("cannot bind %qT lvalue to %qT",
5057 TREE_TYPE (expr), totype);
5059 error (" initializing argument %P of %q+D", argnum, fn);
5061 return error_mark_node;
5064 /* If necessary, create a temporary.
5066 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5067 that need temporaries, even when their types are reference
5068 compatible with the type of reference being bound, so the
5069 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5071 if (convs->need_temporary_p
5072 || TREE_CODE (expr) == CONSTRUCTOR
5073 || TREE_CODE (expr) == VA_ARG_EXPR)
5075 tree type = convs->u.next->type;
5076 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5078 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
5079 && !TYPE_REF_IS_RVALUE (ref_type))
5081 if (complain & tf_error)
5083 /* If the reference is volatile or non-const, we
5084 cannot create a temporary. */
5085 if (lvalue & clk_bitfield)
5086 error ("cannot bind bitfield %qE to %qT",
5088 else if (lvalue & clk_packed)
5089 error ("cannot bind packed field %qE to %qT",
5092 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5094 return error_mark_node;
5096 /* If the source is a packed field, and we must use a copy
5097 constructor, then building the target expr will require
5098 binding the field to the reference parameter to the
5099 copy constructor, and we'll end up with an infinite
5100 loop. If we can use a bitwise copy, then we'll be
5102 if ((lvalue & clk_packed)
5103 && CLASS_TYPE_P (type)
5104 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
5106 if (complain & tf_error)
5107 error ("cannot bind packed field %qE to %qT",
5109 return error_mark_node;
5111 if (lvalue & clk_bitfield)
5113 expr = convert_bitfield_to_declared_type (expr);
5114 expr = fold_convert (type, expr);
5116 expr = build_target_expr_with_type (expr, type);
5119 /* Take the address of the thing to which we will bind the
5121 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5122 if (expr == error_mark_node)
5123 return error_mark_node;
5125 /* Convert it to a pointer to the type referred to by the
5126 reference. This will adjust the pointer if a derived to
5127 base conversion is being performed. */
5128 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5130 /* Convert the pointer to the desired reference type. */
5131 return build_nop (ref_type, expr);
5135 return decay_conversion (expr);
5138 /* Warn about deprecated conversion if appropriate. */
5139 string_conv_p (totype, expr, 1);
5144 expr = convert_to_base (expr, totype, !c_cast_p,
5146 return build_nop (totype, expr);
5149 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5156 if (convs->check_narrowing)
5157 check_narrowing (totype, expr);
5159 if (issue_conversion_warnings && (complain & tf_warning))
5160 expr = convert_and_check (totype, expr);
5162 expr = convert (totype, expr);
5167 /* ARG is being passed to a varargs function. Perform any conversions
5168 required. Return the converted value. */
5171 convert_arg_to_ellipsis (tree arg)
5175 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5176 standard conversions are performed. */
5177 arg = decay_conversion (arg);
5180 If the argument has integral or enumeration type that is subject
5181 to the integral promotions (_conv.prom_), or a floating point
5182 type that is subject to the floating point promotion
5183 (_conv.fpprom_), the value of the argument is converted to the
5184 promoted type before the call. */
5185 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5186 && (TYPE_PRECISION (TREE_TYPE (arg))
5187 < TYPE_PRECISION (double_type_node))
5188 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (arg))))
5189 arg = convert_to_real (double_type_node, arg);
5190 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5191 arg = perform_integral_promotions (arg);
5193 arg = require_complete_type (arg);
5195 if (arg != error_mark_node
5196 && (type_has_nontrivial_copy_init (TREE_TYPE (arg))
5197 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (arg))))
5199 /* [expr.call] 5.2.2/7:
5200 Passing a potentially-evaluated argument of class type (Clause 9)
5201 with a non-trivial copy constructor or a non-trivial destructor
5202 with no corresponding parameter is conditionally-supported, with
5203 implementation-defined semantics.
5205 We used to just warn here and do a bitwise copy, but now
5206 cp_expr_size will abort if we try to do that.
5208 If the call appears in the context of a sizeof expression,
5209 it is not potentially-evaluated. */
5210 if (cp_unevaluated_operand == 0)
5211 error ("cannot pass objects of non-trivially-copyable "
5212 "type %q#T through %<...%>", TREE_TYPE (arg));
5218 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5221 build_x_va_arg (tree expr, tree type)
5223 if (processing_template_decl)
5224 return build_min (VA_ARG_EXPR, type, expr);
5226 type = complete_type_or_else (type, NULL_TREE);
5228 if (expr == error_mark_node || !type)
5229 return error_mark_node;
5231 if (type_has_nontrivial_copy_init (type)
5232 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5233 || TREE_CODE (type) == REFERENCE_TYPE)
5235 /* Remove reference types so we don't ICE later on. */
5236 tree type1 = non_reference (type);
5237 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5238 error ("cannot receive objects of non-trivially-copyable type %q#T "
5239 "through %<...%>; ", type);
5240 expr = convert (build_pointer_type (type1), null_node);
5241 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
5245 return build_va_arg (input_location, expr, type);
5248 /* TYPE has been given to va_arg. Apply the default conversions which
5249 would have happened when passed via ellipsis. Return the promoted
5250 type, or the passed type if there is no change. */
5253 cxx_type_promotes_to (tree type)
5257 /* Perform the array-to-pointer and function-to-pointer
5259 type = type_decays_to (type);
5261 promote = type_promotes_to (type);
5262 if (same_type_p (type, promote))
5268 /* ARG is a default argument expression being passed to a parameter of
5269 the indicated TYPE, which is a parameter to FN. Do any required
5270 conversions. Return the converted value. */
5272 static GTY(()) VEC(tree,gc) *default_arg_context;
5275 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5280 /* If the ARG is an unparsed default argument expression, the
5281 conversion cannot be performed. */
5282 if (TREE_CODE (arg) == DEFAULT_ARG)
5284 error ("the default argument for parameter %d of %qD has "
5285 "not yet been parsed",
5287 return error_mark_node;
5290 /* Detect recursion. */
5291 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5294 error ("recursive evaluation of default argument for %q#D", fn);
5295 return error_mark_node;
5297 VEC_safe_push (tree, gc, default_arg_context, fn);
5299 if (fn && DECL_TEMPLATE_INFO (fn))
5300 arg = tsubst_default_argument (fn, type, arg);
5306 The names in the expression are bound, and the semantic
5307 constraints are checked, at the point where the default
5308 expressions appears.
5310 we must not perform access checks here. */
5311 push_deferring_access_checks (dk_no_check);
5312 arg = break_out_target_exprs (arg);
5313 if (TREE_CODE (arg) == CONSTRUCTOR)
5315 arg = digest_init (type, arg);
5316 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5317 "default argument", fn, parmnum,
5318 tf_warning_or_error);
5322 /* We must make a copy of ARG, in case subsequent processing
5323 alters any part of it. For example, during gimplification a
5324 cast of the form (T) &X::f (where "f" is a member function)
5325 will lead to replacing the PTRMEM_CST for &X::f with a
5326 VAR_DECL. We can avoid the copy for constants, since they
5327 are never modified in place. */
5328 if (!CONSTANT_CLASS_P (arg))
5329 arg = unshare_expr (arg);
5330 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5331 "default argument", fn, parmnum,
5332 tf_warning_or_error);
5333 arg = convert_for_arg_passing (type, arg);
5335 pop_deferring_access_checks();
5337 VEC_pop (tree, default_arg_context);
5342 /* Returns the type which will really be used for passing an argument of
5346 type_passed_as (tree type)
5348 /* Pass classes with copy ctors by invisible reference. */
5349 if (TREE_ADDRESSABLE (type))
5351 type = build_reference_type (type);
5352 /* There are no other pointers to this temporary. */
5353 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5355 else if (targetm.calls.promote_prototypes (type)
5356 && INTEGRAL_TYPE_P (type)
5357 && COMPLETE_TYPE_P (type)
5358 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5359 TYPE_SIZE (integer_type_node)))
5360 type = integer_type_node;
5365 /* Actually perform the appropriate conversion. */
5368 convert_for_arg_passing (tree type, tree val)
5372 /* If VAL is a bitfield, then -- since it has already been converted
5373 to TYPE -- it cannot have a precision greater than TYPE.
5375 If it has a smaller precision, we must widen it here. For
5376 example, passing "int f:3;" to a function expecting an "int" will
5377 not result in any conversion before this point.
5379 If the precision is the same we must not risk widening. For
5380 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5381 often have type "int", even though the C++ type for the field is
5382 "long long". If the value is being passed to a function
5383 expecting an "int", then no conversions will be required. But,
5384 if we call convert_bitfield_to_declared_type, the bitfield will
5385 be converted to "long long". */
5386 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5388 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5389 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5391 if (val == error_mark_node)
5393 /* Pass classes with copy ctors by invisible reference. */
5394 else if (TREE_ADDRESSABLE (type))
5395 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5396 else if (targetm.calls.promote_prototypes (type)
5397 && INTEGRAL_TYPE_P (type)
5398 && COMPLETE_TYPE_P (type)
5399 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5400 TYPE_SIZE (integer_type_node)))
5401 val = perform_integral_promotions (val);
5402 if (warn_missing_format_attribute)
5404 tree rhstype = TREE_TYPE (val);
5405 const enum tree_code coder = TREE_CODE (rhstype);
5406 const enum tree_code codel = TREE_CODE (type);
5407 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5409 && check_missing_format_attribute (type, rhstype))
5410 warning (OPT_Wmissing_format_attribute,
5411 "argument of function call might be a candidate for a format attribute");
5416 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5417 which no conversions at all should be done. This is true for some
5418 builtins which don't act like normal functions. */
5421 magic_varargs_p (tree fn)
5423 if (DECL_BUILT_IN (fn))
5424 switch (DECL_FUNCTION_CODE (fn))
5426 case BUILT_IN_CLASSIFY_TYPE:
5427 case BUILT_IN_CONSTANT_P:
5428 case BUILT_IN_NEXT_ARG:
5429 case BUILT_IN_VA_START:
5433 return lookup_attribute ("type generic",
5434 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5440 /* Subroutine of the various build_*_call functions. Overload resolution
5441 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5442 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5443 bitmask of various LOOKUP_* flags which apply to the call itself. */
5446 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5449 const VEC(tree,gc) *args = cand->args;
5450 tree first_arg = cand->first_arg;
5451 conversion **convs = cand->convs;
5453 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5458 unsigned int arg_index = 0;
5462 bool already_used = false;
5464 /* In a template, there is no need to perform all of the work that
5465 is normally done. We are only interested in the type of the call
5466 expression, i.e., the return type of the function. Any semantic
5467 errors will be deferred until the template is instantiated. */
5468 if (processing_template_decl)
5472 const tree *argarray;
5475 return_type = TREE_TYPE (TREE_TYPE (fn));
5476 nargs = VEC_length (tree, args);
5477 if (first_arg == NULL_TREE)
5478 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5486 alcarray = XALLOCAVEC (tree, nargs);
5487 alcarray[0] = first_arg;
5488 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5489 alcarray[ix + 1] = arg;
5490 argarray = alcarray;
5492 expr = build_call_array_loc (input_location,
5493 return_type, build_addr_func (fn), nargs,
5495 if (TREE_THIS_VOLATILE (fn) && cfun)
5496 current_function_returns_abnormally = 1;
5497 if (!VOID_TYPE_P (return_type))
5498 require_complete_type (return_type);
5499 return convert_from_reference (expr);
5502 /* Give any warnings we noticed during overload resolution. */
5505 struct candidate_warning *w;
5506 for (w = cand->warnings; w; w = w->next)
5507 joust (cand, w->loser, 1);
5510 /* Make =delete work with SFINAE. */
5511 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5512 return error_mark_node;
5514 if (DECL_FUNCTION_MEMBER_P (fn))
5516 /* If FN is a template function, two cases must be considered.
5521 template <class T> void f();
5523 template <class T> struct B {
5527 struct C : A, B<int> {
5529 using B<int>::g; // #2
5532 In case #1 where `A::f' is a member template, DECL_ACCESS is
5533 recorded in the primary template but not in its specialization.
5534 We check access of FN using its primary template.
5536 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5537 because it is a member of class template B, DECL_ACCESS is
5538 recorded in the specialization `B<int>::g'. We cannot use its
5539 primary template because `B<T>::g' and `B<int>::g' may have
5540 different access. */
5541 if (DECL_TEMPLATE_INFO (fn)
5542 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5543 perform_or_defer_access_check (cand->access_path,
5544 DECL_TI_TEMPLATE (fn), fn);
5546 perform_or_defer_access_check (cand->access_path, fn, fn);
5549 /* Find maximum size of vector to hold converted arguments. */
5550 parmlen = list_length (parm);
5551 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5552 if (parmlen > nargs)
5554 argarray = (tree *) alloca (nargs * sizeof (tree));
5556 /* The implicit parameters to a constructor are not considered by overload
5557 resolution, and must be of the proper type. */
5558 if (DECL_CONSTRUCTOR_P (fn))
5560 if (first_arg != NULL_TREE)
5562 argarray[j++] = first_arg;
5563 first_arg = NULL_TREE;
5567 argarray[j++] = VEC_index (tree, args, arg_index);
5570 parm = TREE_CHAIN (parm);
5571 /* We should never try to call the abstract constructor. */
5572 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5574 if (DECL_HAS_VTT_PARM_P (fn))
5576 argarray[j++] = VEC_index (tree, args, arg_index);
5578 parm = TREE_CHAIN (parm);
5581 /* Bypass access control for 'this' parameter. */
5582 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5584 tree parmtype = TREE_VALUE (parm);
5585 tree arg = (first_arg != NULL_TREE
5587 : VEC_index (tree, args, arg_index));
5588 tree argtype = TREE_TYPE (arg);
5592 if (convs[i]->bad_p)
5594 if (complain & tf_error)
5595 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5596 TREE_TYPE (argtype), fn);
5598 return error_mark_node;
5601 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5602 X is called for an object that is not of type X, or of a type
5603 derived from X, the behavior is undefined.
5605 So we can assume that anything passed as 'this' is non-null, and
5606 optimize accordingly. */
5607 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5608 /* Convert to the base in which the function was declared. */
5609 gcc_assert (cand->conversion_path != NULL_TREE);
5610 converted_arg = build_base_path (PLUS_EXPR,
5612 cand->conversion_path,
5614 /* Check that the base class is accessible. */
5615 if (!accessible_base_p (TREE_TYPE (argtype),
5616 BINFO_TYPE (cand->conversion_path), true))
5617 error ("%qT is not an accessible base of %qT",
5618 BINFO_TYPE (cand->conversion_path),
5619 TREE_TYPE (argtype));
5620 /* If fn was found by a using declaration, the conversion path
5621 will be to the derived class, not the base declaring fn. We
5622 must convert from derived to base. */
5623 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5624 TREE_TYPE (parmtype), ba_unique, NULL);
5625 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5628 argarray[j++] = converted_arg;
5629 parm = TREE_CHAIN (parm);
5630 if (first_arg != NULL_TREE)
5631 first_arg = NULL_TREE;
5638 gcc_assert (first_arg == NULL_TREE);
5639 for (; arg_index < VEC_length (tree, args) && parm;
5640 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5642 tree type = TREE_VALUE (parm);
5646 /* Don't make a copy here if build_call is going to. */
5647 if (conv->kind == ck_rvalue
5648 && COMPLETE_TYPE_P (complete_type (type))
5649 && !TREE_ADDRESSABLE (type))
5650 conv = conv->u.next;
5652 /* Warn about initializer_list deduction that isn't currently in the
5654 if (cxx_dialect > cxx98
5655 && flag_deduce_init_list
5656 && cand->template_decl
5657 && is_std_init_list (non_reference (type)))
5659 tree tmpl = TI_TEMPLATE (cand->template_decl);
5660 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
5661 tree patparm = get_pattern_parm (realparm, tmpl);
5662 tree pattype = TREE_TYPE (patparm);
5663 if (PACK_EXPANSION_P (pattype))
5664 pattype = PACK_EXPANSION_PATTERN (pattype);
5665 pattype = non_reference (pattype);
5667 if (!is_std_init_list (pattype))
5669 pedwarn (input_location, 0, "deducing %qT as %qT",
5670 non_reference (TREE_TYPE (patparm)),
5671 non_reference (type));
5672 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
5673 pedwarn (input_location, 0,
5674 " (you can disable this with -fno-deduce-init-list)");
5678 val = convert_like_with_context
5679 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5682 val = convert_for_arg_passing (type, val);
5683 if (val == error_mark_node)
5684 return error_mark_node;
5686 argarray[j++] = val;
5689 /* Default arguments */
5690 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5691 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5692 TREE_PURPOSE (parm),
5695 for (; arg_index < VEC_length (tree, args); ++arg_index)
5697 tree a = VEC_index (tree, args, arg_index);
5698 if (magic_varargs_p (fn))
5699 /* Do no conversions for magic varargs. */;
5701 a = convert_arg_to_ellipsis (a);
5705 gcc_assert (j <= nargs);
5708 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5709 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5711 /* Avoid actually calling copy constructors and copy assignment operators,
5714 if (! flag_elide_constructors)
5715 /* Do things the hard way. */;
5716 else if (cand->num_convs == 1
5717 && (DECL_COPY_CONSTRUCTOR_P (fn)
5718 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5721 tree arg = argarray[num_artificial_parms_for (fn)];
5724 /* Pull out the real argument, disregarding const-correctness. */
5726 while (CONVERT_EXPR_P (targ)
5727 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5728 targ = TREE_OPERAND (targ, 0);
5729 if (TREE_CODE (targ) == ADDR_EXPR)
5731 targ = TREE_OPERAND (targ, 0);
5732 if (!same_type_ignoring_top_level_qualifiers_p
5733 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5742 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
5744 if (TREE_CODE (arg) == TARGET_EXPR
5745 && TARGET_EXPR_LIST_INIT_P (arg))
5747 /* Copy-list-initialization doesn't require the copy constructor
5750 /* [class.copy]: the copy constructor is implicitly defined even if
5751 the implementation elided its use. */
5752 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5755 already_used = true;
5758 /* If we're creating a temp and we already have one, don't create a
5759 new one. If we're not creating a temp but we get one, use
5760 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5761 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5762 temp or an INIT_EXPR otherwise. */
5763 fa = (cand->first_arg != NULL_TREE
5765 : VEC_index (tree, args, 0));
5766 if (integer_zerop (fa))
5768 if (TREE_CODE (arg) == TARGET_EXPR)
5770 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5771 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5773 else if (TREE_CODE (arg) == TARGET_EXPR
5774 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5775 && !move_fn_p (fn)))
5777 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
5779 tree type = TREE_TYPE (to);
5781 if (TREE_CODE (arg) != TARGET_EXPR
5782 && TREE_CODE (arg) != AGGR_INIT_EXPR
5783 && is_really_empty_class (type))
5785 /* Avoid copying empty classes. */
5786 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
5787 TREE_NO_WARNING (val) = 1;
5788 val = build2 (COMPOUND_EXPR, type, val, to);
5789 TREE_NO_WARNING (val) = 1;
5792 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5796 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5798 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5800 tree to = stabilize_reference
5801 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
5802 tree type = TREE_TYPE (to);
5803 tree as_base = CLASSTYPE_AS_BASE (type);
5804 tree arg = argarray[1];
5806 if (is_really_empty_class (type))
5808 /* Avoid copying empty classes. */
5809 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
5810 TREE_NO_WARNING (val) = 1;
5811 val = build2 (COMPOUND_EXPR, type, val, to);
5812 TREE_NO_WARNING (val) = 1;
5814 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5816 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
5817 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5821 /* We must only copy the non-tail padding parts.
5822 Use __builtin_memcpy for the bitwise copy.
5823 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5824 instead of an explicit call to memcpy. */
5826 tree arg0, arg1, arg2, t;
5827 tree test = NULL_TREE;
5829 arg2 = TYPE_SIZE_UNIT (as_base);
5831 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5833 if (!can_trust_pointer_alignment ())
5835 /* If we can't be sure about pointer alignment, a call
5836 to __builtin_memcpy is expanded as a call to memcpy, which
5837 is invalid with identical args. Otherwise it is
5838 expanded as a block move, which should be safe. */
5839 arg0 = save_expr (arg0);
5840 arg1 = save_expr (arg1);
5841 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5843 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5844 t = build_call_n (t, 3, arg0, arg1, arg2);
5846 t = convert (TREE_TYPE (arg0), t);
5848 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5849 val = cp_build_indirect_ref (t, RO_NULL, complain);
5850 TREE_NO_WARNING (val) = 1;
5859 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5862 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5865 gcc_assert (binfo && binfo != error_mark_node);
5867 /* Warn about deprecated virtual functions now, since we're about
5868 to throw away the decl. */
5869 if (TREE_DEPRECATED (fn))
5870 warn_deprecated_use (fn, NULL_TREE);
5872 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5873 if (TREE_SIDE_EFFECTS (argarray[0]))
5874 argarray[0] = save_expr (argarray[0]);
5875 t = build_pointer_type (TREE_TYPE (fn));
5876 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5877 fn = build_java_interface_fn_ref (fn, argarray[0]);
5879 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5883 fn = build_addr_func (fn);
5885 return build_cxx_call (fn, nargs, argarray);
5888 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5889 This function performs no overload resolution, conversion, or other
5890 high-level operations. */
5893 build_cxx_call (tree fn, int nargs, tree *argarray)
5897 fn = build_call_a (fn, nargs, argarray);
5899 /* If this call might throw an exception, note that fact. */
5900 fndecl = get_callee_fndecl (fn);
5901 if ((!fndecl || !TREE_NOTHROW (fndecl))
5902 && at_function_scope_p ()
5904 cp_function_chain->can_throw = 1;
5906 /* Check that arguments to builtin functions match the expectations. */
5908 && DECL_BUILT_IN (fndecl)
5909 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5910 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5911 return error_mark_node;
5913 /* Some built-in function calls will be evaluated at compile-time in
5915 fn = fold_if_not_in_template (fn);
5917 if (VOID_TYPE_P (TREE_TYPE (fn)))
5920 fn = require_complete_type (fn);
5921 if (fn == error_mark_node)
5922 return error_mark_node;
5924 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5925 fn = build_cplus_new (TREE_TYPE (fn), fn);
5926 return convert_from_reference (fn);
5929 static GTY(()) tree java_iface_lookup_fn;
5931 /* Make an expression which yields the address of the Java interface
5932 method FN. This is achieved by generating a call to libjava's
5933 _Jv_LookupInterfaceMethodIdx(). */
5936 build_java_interface_fn_ref (tree fn, tree instance)
5938 tree lookup_fn, method, idx;
5939 tree klass_ref, iface, iface_ref;
5942 if (!java_iface_lookup_fn)
5944 tree endlink = build_void_list_node ();
5945 tree t = tree_cons (NULL_TREE, ptr_type_node,
5946 tree_cons (NULL_TREE, ptr_type_node,
5947 tree_cons (NULL_TREE, java_int_type_node,
5949 java_iface_lookup_fn
5950 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5951 build_function_type (ptr_type_node, t),
5952 0, NOT_BUILT_IN, NULL, NULL_TREE);
5955 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5956 This is the first entry in the vtable. */
5957 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
5958 tf_warning_or_error),
5961 /* Get the java.lang.Class pointer for the interface being called. */
5962 iface = DECL_CONTEXT (fn);
5963 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5964 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5965 || DECL_CONTEXT (iface_ref) != iface)
5967 error ("could not find class$ field in java interface type %qT",
5969 return error_mark_node;
5971 iface_ref = build_address (iface_ref);
5972 iface_ref = convert (build_pointer_type (iface), iface_ref);
5974 /* Determine the itable index of FN. */
5976 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5978 if (!DECL_VIRTUAL_P (method))
5984 idx = build_int_cst (NULL_TREE, i);
5986 lookup_fn = build1 (ADDR_EXPR,
5987 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5988 java_iface_lookup_fn);
5989 return build_call_nary (ptr_type_node, lookup_fn,
5990 3, klass_ref, iface_ref, idx);
5993 /* Returns the value to use for the in-charge parameter when making a
5994 call to a function with the indicated NAME.
5996 FIXME:Can't we find a neater way to do this mapping? */
5999 in_charge_arg_for_name (tree name)
6001 if (name == base_ctor_identifier
6002 || name == base_dtor_identifier)
6003 return integer_zero_node;
6004 else if (name == complete_ctor_identifier)
6005 return integer_one_node;
6006 else if (name == complete_dtor_identifier)
6007 return integer_two_node;
6008 else if (name == deleting_dtor_identifier)
6009 return integer_three_node;
6011 /* This function should only be called with one of the names listed
6017 /* Build a call to a constructor, destructor, or an assignment
6018 operator for INSTANCE, an expression with class type. NAME
6019 indicates the special member function to call; *ARGS are the
6020 arguments. ARGS may be NULL. This may change ARGS. BINFO
6021 indicates the base of INSTANCE that is to be passed as the `this'
6022 parameter to the member function called.
6024 FLAGS are the LOOKUP_* flags to use when processing the call.
6026 If NAME indicates a complete object constructor, INSTANCE may be
6027 NULL_TREE. In this case, the caller will call build_cplus_new to
6028 store the newly constructed object into a VAR_DECL. */
6031 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6032 tree binfo, int flags, tsubst_flags_t complain)
6035 /* The type of the subobject to be constructed or destroyed. */
6037 VEC(tree,gc) *allocated = NULL;
6040 gcc_assert (name == complete_ctor_identifier
6041 || name == base_ctor_identifier
6042 || name == complete_dtor_identifier
6043 || name == base_dtor_identifier
6044 || name == deleting_dtor_identifier
6045 || name == ansi_assopname (NOP_EXPR));
6048 /* Resolve the name. */
6049 if (!complete_type_or_else (binfo, NULL_TREE))
6050 return error_mark_node;
6052 binfo = TYPE_BINFO (binfo);
6055 gcc_assert (binfo != NULL_TREE);
6057 class_type = BINFO_TYPE (binfo);
6059 /* Handle the special case where INSTANCE is NULL_TREE. */
6060 if (name == complete_ctor_identifier && !instance)
6062 instance = build_int_cst (build_pointer_type (class_type), 0);
6063 instance = build1 (INDIRECT_REF, class_type, instance);
6067 if (name == complete_dtor_identifier
6068 || name == base_dtor_identifier
6069 || name == deleting_dtor_identifier)
6070 gcc_assert (args == NULL || VEC_empty (tree, *args));
6072 /* Convert to the base class, if necessary. */
6073 if (!same_type_ignoring_top_level_qualifiers_p
6074 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6076 if (name != ansi_assopname (NOP_EXPR))
6077 /* For constructors and destructors, either the base is
6078 non-virtual, or it is virtual but we are doing the
6079 conversion from a constructor or destructor for the
6080 complete object. In either case, we can convert
6082 instance = convert_to_base_statically (instance, binfo);
6084 /* However, for assignment operators, we must convert
6085 dynamically if the base is virtual. */
6086 instance = build_base_path (PLUS_EXPR, instance,
6087 binfo, /*nonnull=*/1);
6091 gcc_assert (instance != NULL_TREE);
6093 fns = lookup_fnfields (binfo, name, 1);
6095 /* When making a call to a constructor or destructor for a subobject
6096 that uses virtual base classes, pass down a pointer to a VTT for
6098 if ((name == base_ctor_identifier
6099 || name == base_dtor_identifier)
6100 && CLASSTYPE_VBASECLASSES (class_type))
6105 /* If the current function is a complete object constructor
6106 or destructor, then we fetch the VTT directly.
6107 Otherwise, we look it up using the VTT we were given. */
6108 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6109 vtt = decay_conversion (vtt);
6110 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6111 build2 (EQ_EXPR, boolean_type_node,
6112 current_in_charge_parm, integer_zero_node),
6115 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6116 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6117 BINFO_SUBVTT_INDEX (binfo));
6121 allocated = make_tree_vector ();
6125 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6128 ret = build_new_method_call (instance, fns, args,
6129 TYPE_BINFO (BINFO_TYPE (binfo)),
6133 if (allocated != NULL)
6134 release_tree_vector (allocated);
6139 /* Return the NAME, as a C string. The NAME indicates a function that
6140 is a member of TYPE. *FREE_P is set to true if the caller must
6141 free the memory returned.
6143 Rather than go through all of this, we should simply set the names
6144 of constructors and destructors appropriately, and dispense with
6145 ctor_identifier, dtor_identifier, etc. */
6148 name_as_c_string (tree name, tree type, bool *free_p)
6152 /* Assume that we will not allocate memory. */
6154 /* Constructors and destructors are special. */
6155 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6158 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6159 /* For a destructor, add the '~'. */
6160 if (name == complete_dtor_identifier
6161 || name == base_dtor_identifier
6162 || name == deleting_dtor_identifier)
6164 pretty_name = concat ("~", pretty_name, NULL);
6165 /* Remember that we need to free the memory allocated. */
6169 else if (IDENTIFIER_TYPENAME_P (name))
6171 pretty_name = concat ("operator ",
6172 type_as_string_translate (TREE_TYPE (name),
6173 TFF_PLAIN_IDENTIFIER),
6175 /* Remember that we need to free the memory allocated. */
6179 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6184 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6185 be set, upon return, to the function called. ARGS may be NULL.
6186 This may change ARGS. */
6189 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6190 tree conversion_path, int flags,
6191 tree *fn_p, tsubst_flags_t complain)
6193 struct z_candidate *candidates = 0, *cand;
6194 tree explicit_targs = NULL_TREE;
6195 tree basetype = NULL_TREE;
6198 tree first_mem_arg = NULL_TREE;
6201 bool skip_first_for_error;
6202 VEC(tree,gc) *user_args;
6206 int template_only = 0;
6210 VEC(tree,gc) *orig_args = NULL;
6213 gcc_assert (instance != NULL_TREE);
6215 /* We don't know what function we're going to call, yet. */
6219 if (error_operand_p (instance)
6220 || error_operand_p (fns))
6221 return error_mark_node;
6223 if (!BASELINK_P (fns))
6225 if (complain & tf_error)
6226 error ("call to non-function %qD", fns);
6227 return error_mark_node;
6230 orig_instance = instance;
6233 /* Dismantle the baselink to collect all the information we need. */
6234 if (!conversion_path)
6235 conversion_path = BASELINK_BINFO (fns);
6236 access_binfo = BASELINK_ACCESS_BINFO (fns);
6237 optype = BASELINK_OPTYPE (fns);
6238 fns = BASELINK_FUNCTIONS (fns);
6239 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6241 explicit_targs = TREE_OPERAND (fns, 1);
6242 fns = TREE_OPERAND (fns, 0);
6245 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6246 || TREE_CODE (fns) == TEMPLATE_DECL
6247 || TREE_CODE (fns) == OVERLOAD);
6248 fn = get_first_fn (fns);
6249 name = DECL_NAME (fn);
6251 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6252 gcc_assert (CLASS_TYPE_P (basetype));
6254 if (processing_template_decl)
6256 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6257 instance = build_non_dependent_expr (instance);
6259 make_args_non_dependent (*args);
6262 user_args = args == NULL ? NULL : *args;
6263 /* Under DR 147 A::A() is an invalid constructor call,
6264 not a functional cast. */
6265 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
6267 if (! (complain & tf_error))
6268 return error_mark_node;
6270 permerror (input_location,
6271 "cannot call constructor %<%T::%D%> directly",
6273 permerror (input_location, " for a function-style cast, remove the "
6274 "redundant %<::%D%>", name);
6275 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
6280 /* Figure out whether to skip the first argument for the error
6281 message we will display to users if an error occurs. We don't
6282 want to display any compiler-generated arguments. The "this"
6283 pointer hasn't been added yet. However, we must remove the VTT
6284 pointer if this is a call to a base-class constructor or
6286 skip_first_for_error = false;
6287 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6289 /* Callers should explicitly indicate whether they want to construct
6290 the complete object or just the part without virtual bases. */
6291 gcc_assert (name != ctor_identifier);
6292 /* Similarly for destructors. */
6293 gcc_assert (name != dtor_identifier);
6294 /* Remove the VTT pointer, if present. */
6295 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6296 && CLASSTYPE_VBASECLASSES (basetype))
6297 skip_first_for_error = true;
6300 /* Process the argument list. */
6301 if (args != NULL && *args != NULL)
6303 *args = resolve_args (*args);
6305 return error_mark_node;
6308 instance_ptr = build_this (instance);
6310 /* It's OK to call destructors and constructors on cv-qualified objects.
6311 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6313 if (DECL_DESTRUCTOR_P (fn)
6314 || DECL_CONSTRUCTOR_P (fn))
6316 tree type = build_pointer_type (basetype);
6317 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6318 instance_ptr = build_nop (type, instance_ptr);
6320 if (DECL_DESTRUCTOR_P (fn))
6321 name = complete_dtor_identifier;
6323 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6324 initializer, not T({ }). If the type doesn't have a list ctor,
6325 break apart the list into separate ctor args. */
6326 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6327 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6328 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6329 && !TYPE_HAS_LIST_CTOR (basetype))
6331 gcc_assert (VEC_length (tree, *args) == 1);
6332 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6335 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6336 first_mem_arg = instance_ptr;
6338 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6339 p = conversion_obstack_alloc (0);
6341 for (fn = fns; fn; fn = OVL_NEXT (fn))
6343 tree t = OVL_CURRENT (fn);
6344 tree this_first_arg;
6346 /* We can end up here for copy-init of same or base class. */
6347 if ((flags & LOOKUP_ONLYCONVERTING)
6348 && DECL_NONCONVERTING_P (t))
6351 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6352 this_first_arg = first_mem_arg;
6354 this_first_arg = NULL_TREE;
6356 if (TREE_CODE (t) == TEMPLATE_DECL)
6357 /* A member template. */
6358 add_template_candidate (&candidates, t,
6362 args == NULL ? NULL : *args,
6368 else if (! template_only)
6369 add_function_candidate (&candidates, t,
6372 args == NULL ? NULL : *args,
6378 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6381 if (complain & tf_error)
6383 if (!COMPLETE_TYPE_P (basetype))
6384 cxx_incomplete_type_error (instance_ptr, basetype);
6391 pretty_name = name_as_c_string (name, basetype, &free_p);
6392 arglist = build_tree_list_vec (user_args);
6393 if (skip_first_for_error)
6394 arglist = TREE_CHAIN (arglist);
6395 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6396 basetype, pretty_name, arglist,
6397 TREE_TYPE (TREE_TYPE (instance_ptr)));
6401 print_z_candidates (candidates);
6403 call = error_mark_node;
6407 cand = tourney (candidates);
6414 if (complain & tf_error)
6416 pretty_name = name_as_c_string (name, basetype, &free_p);
6417 arglist = build_tree_list_vec (user_args);
6418 if (skip_first_for_error)
6419 arglist = TREE_CHAIN (arglist);
6420 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6422 print_z_candidates (candidates);
6426 call = error_mark_node;
6432 if (!(flags & LOOKUP_NONVIRTUAL)
6433 && DECL_PURE_VIRTUAL_P (fn)
6434 && instance == current_class_ref
6435 && (DECL_CONSTRUCTOR_P (current_function_decl)
6436 || DECL_DESTRUCTOR_P (current_function_decl))
6437 && (complain & tf_warning))
6438 /* This is not an error, it is runtime undefined
6440 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6441 "abstract virtual %q#D called from constructor"
6442 : "abstract virtual %q#D called from destructor"),
6445 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6446 && is_dummy_object (instance_ptr))
6448 if (complain & tf_error)
6449 error ("cannot call member function %qD without object",
6451 call = error_mark_node;
6455 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6456 && resolves_to_fixed_type_p (instance, 0))
6457 flags |= LOOKUP_NONVIRTUAL;
6458 /* Now we know what function is being called. */
6461 /* Build the actual CALL_EXPR. */
6462 call = build_over_call (cand, flags, complain);
6463 /* In an expression of the form `a->f()' where `f' turns
6464 out to be a static member function, `a' is
6465 none-the-less evaluated. */
6466 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6467 && !is_dummy_object (instance_ptr)
6468 && TREE_SIDE_EFFECTS (instance_ptr))
6469 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6470 instance_ptr, call);
6471 else if (call != error_mark_node
6472 && DECL_DESTRUCTOR_P (cand->fn)
6473 && !VOID_TYPE_P (TREE_TYPE (call)))
6474 /* An explicit call of the form "x->~X()" has type
6475 "void". However, on platforms where destructors
6476 return "this" (i.e., those where
6477 targetm.cxx.cdtor_returns_this is true), such calls
6478 will appear to have a return value of pointer type
6479 to the low-level call machinery. We do not want to
6480 change the low-level machinery, since we want to be
6481 able to optimize "delete f()" on such platforms as
6482 "operator delete(~X(f()))" (rather than generating
6483 "t = f(), ~X(t), operator delete (t)"). */
6484 call = build_nop (void_type_node, call);
6489 if (processing_template_decl && call != error_mark_node)
6491 bool cast_to_void = false;
6493 if (TREE_CODE (call) == COMPOUND_EXPR)
6494 call = TREE_OPERAND (call, 1);
6495 else if (TREE_CODE (call) == NOP_EXPR)
6497 cast_to_void = true;
6498 call = TREE_OPERAND (call, 0);
6500 if (TREE_CODE (call) == INDIRECT_REF)
6501 call = TREE_OPERAND (call, 0);
6502 call = (build_min_non_dep_call_vec
6504 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6505 orig_instance, orig_fns, NULL_TREE),
6507 call = convert_from_reference (call);
6509 call = build_nop (void_type_node, call);
6512 /* Free all the conversions we allocated. */
6513 obstack_free (&conversion_obstack, p);
6515 if (orig_args != NULL)
6516 release_tree_vector (orig_args);
6521 /* Returns true iff standard conversion sequence ICS1 is a proper
6522 subsequence of ICS2. */
6525 is_subseq (conversion *ics1, conversion *ics2)
6527 /* We can assume that a conversion of the same code
6528 between the same types indicates a subsequence since we only get
6529 here if the types we are converting from are the same. */
6531 while (ics1->kind == ck_rvalue
6532 || ics1->kind == ck_lvalue)
6533 ics1 = ics1->u.next;
6537 while (ics2->kind == ck_rvalue
6538 || ics2->kind == ck_lvalue)
6539 ics2 = ics2->u.next;
6541 if (ics2->kind == ck_user
6542 || ics2->kind == ck_ambig
6543 || ics2->kind == ck_identity)
6544 /* At this point, ICS1 cannot be a proper subsequence of
6545 ICS2. We can get a USER_CONV when we are comparing the
6546 second standard conversion sequence of two user conversion
6550 ics2 = ics2->u.next;
6552 if (ics2->kind == ics1->kind
6553 && same_type_p (ics2->type, ics1->type)
6554 && same_type_p (ics2->u.next->type,
6555 ics1->u.next->type))
6560 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6561 be any _TYPE nodes. */
6564 is_properly_derived_from (tree derived, tree base)
6566 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6569 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6570 considers every class derived from itself. */
6571 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6572 && DERIVED_FROM_P (base, derived));
6575 /* We build the ICS for an implicit object parameter as a pointer
6576 conversion sequence. However, such a sequence should be compared
6577 as if it were a reference conversion sequence. If ICS is the
6578 implicit conversion sequence for an implicit object parameter,
6579 modify it accordingly. */
6582 maybe_handle_implicit_object (conversion **ics)
6586 /* [over.match.funcs]
6588 For non-static member functions, the type of the
6589 implicit object parameter is "reference to cv X"
6590 where X is the class of which the function is a
6591 member and cv is the cv-qualification on the member
6592 function declaration. */
6593 conversion *t = *ics;
6594 tree reference_type;
6596 /* The `this' parameter is a pointer to a class type. Make the
6597 implicit conversion talk about a reference to that same class
6599 reference_type = TREE_TYPE (t->type);
6600 reference_type = build_reference_type (reference_type);
6602 if (t->kind == ck_qual)
6604 if (t->kind == ck_ptr)
6606 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6607 t = direct_reference_binding (reference_type, t);
6609 t->rvaluedness_matches_p = 0;
6614 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6615 and return the initial reference binding conversion. Otherwise,
6616 leave *ICS unchanged and return NULL. */
6619 maybe_handle_ref_bind (conversion **ics)
6621 if ((*ics)->kind == ck_ref_bind)
6623 conversion *old_ics = *ics;
6624 *ics = old_ics->u.next;
6625 (*ics)->user_conv_p = old_ics->user_conv_p;
6632 /* Compare two implicit conversion sequences according to the rules set out in
6633 [over.ics.rank]. Return values:
6635 1: ics1 is better than ics2
6636 -1: ics2 is better than ics1
6637 0: ics1 and ics2 are indistinguishable */
6640 compare_ics (conversion *ics1, conversion *ics2)
6646 tree deref_from_type1 = NULL_TREE;
6647 tree deref_from_type2 = NULL_TREE;
6648 tree deref_to_type1 = NULL_TREE;
6649 tree deref_to_type2 = NULL_TREE;
6650 conversion_rank rank1, rank2;
6652 /* REF_BINDING is nonzero if the result of the conversion sequence
6653 is a reference type. In that case REF_CONV is the reference
6654 binding conversion. */
6655 conversion *ref_conv1;
6656 conversion *ref_conv2;
6658 /* Handle implicit object parameters. */
6659 maybe_handle_implicit_object (&ics1);
6660 maybe_handle_implicit_object (&ics2);
6662 /* Handle reference parameters. */
6663 ref_conv1 = maybe_handle_ref_bind (&ics1);
6664 ref_conv2 = maybe_handle_ref_bind (&ics2);
6666 /* List-initialization sequence L1 is a better conversion sequence than
6667 list-initialization sequence L2 if L1 converts to
6668 std::initializer_list<X> for some X and L2 does not. */
6669 if (ics1->kind == ck_list && ics2->kind != ck_list)
6671 if (ics2->kind == ck_list && ics1->kind != ck_list)
6676 When comparing the basic forms of implicit conversion sequences (as
6677 defined in _over.best.ics_)
6679 --a standard conversion sequence (_over.ics.scs_) is a better
6680 conversion sequence than a user-defined conversion sequence
6681 or an ellipsis conversion sequence, and
6683 --a user-defined conversion sequence (_over.ics.user_) is a
6684 better conversion sequence than an ellipsis conversion sequence
6685 (_over.ics.ellipsis_). */
6686 rank1 = CONVERSION_RANK (ics1);
6687 rank2 = CONVERSION_RANK (ics2);
6691 else if (rank1 < rank2)
6694 if (rank1 == cr_bad)
6696 /* XXX Isn't this an extension? */
6697 /* Both ICS are bad. We try to make a decision based on what
6698 would have happened if they'd been good. */
6699 if (ics1->user_conv_p > ics2->user_conv_p
6700 || ics1->rank > ics2->rank)
6702 else if (ics1->user_conv_p < ics2->user_conv_p
6703 || ics1->rank < ics2->rank)
6706 /* We couldn't make up our minds; try to figure it out below. */
6709 if (ics1->ellipsis_p || ics1->kind == ck_list)
6710 /* Both conversions are ellipsis conversions or both are building a
6711 std::initializer_list. */
6714 /* User-defined conversion sequence U1 is a better conversion sequence
6715 than another user-defined conversion sequence U2 if they contain the
6716 same user-defined conversion operator or constructor and if the sec-
6717 ond standard conversion sequence of U1 is better than the second
6718 standard conversion sequence of U2. */
6720 if (ics1->user_conv_p)
6725 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6726 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6728 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6729 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6732 if (t1->cand->fn != t2->cand->fn)
6735 /* We can just fall through here, after setting up
6736 FROM_TYPE1 and FROM_TYPE2. */
6737 from_type1 = t1->type;
6738 from_type2 = t2->type;
6745 /* We're dealing with two standard conversion sequences.
6749 Standard conversion sequence S1 is a better conversion
6750 sequence than standard conversion sequence S2 if
6752 --S1 is a proper subsequence of S2 (comparing the conversion
6753 sequences in the canonical form defined by _over.ics.scs_,
6754 excluding any Lvalue Transformation; the identity
6755 conversion sequence is considered to be a subsequence of
6756 any non-identity conversion sequence */
6759 while (t1->kind != ck_identity)
6761 from_type1 = t1->type;
6764 while (t2->kind != ck_identity)
6766 from_type2 = t2->type;
6769 /* One sequence can only be a subsequence of the other if they start with
6770 the same type. They can start with different types when comparing the
6771 second standard conversion sequence in two user-defined conversion
6773 if (same_type_p (from_type1, from_type2))
6775 if (is_subseq (ics1, ics2))
6777 if (is_subseq (ics2, ics1))
6785 --the rank of S1 is better than the rank of S2 (by the rules
6788 Standard conversion sequences are ordered by their ranks: an Exact
6789 Match is a better conversion than a Promotion, which is a better
6790 conversion than a Conversion.
6792 Two conversion sequences with the same rank are indistinguishable
6793 unless one of the following rules applies:
6795 --A conversion that is not a conversion of a pointer, or pointer
6796 to member, to bool is better than another conversion that is such
6799 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6800 so that we do not have to check it explicitly. */
6801 if (ics1->rank < ics2->rank)
6803 else if (ics2->rank < ics1->rank)
6806 to_type1 = ics1->type;
6807 to_type2 = ics2->type;
6809 /* A conversion from scalar arithmetic type to complex is worse than a
6810 conversion between scalar arithmetic types. */
6811 if (same_type_p (from_type1, from_type2)
6812 && ARITHMETIC_TYPE_P (from_type1)
6813 && ARITHMETIC_TYPE_P (to_type1)
6814 && ARITHMETIC_TYPE_P (to_type2)
6815 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6816 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6818 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6824 if (TYPE_PTR_P (from_type1)
6825 && TYPE_PTR_P (from_type2)
6826 && TYPE_PTR_P (to_type1)
6827 && TYPE_PTR_P (to_type2))
6829 deref_from_type1 = TREE_TYPE (from_type1);
6830 deref_from_type2 = TREE_TYPE (from_type2);
6831 deref_to_type1 = TREE_TYPE (to_type1);
6832 deref_to_type2 = TREE_TYPE (to_type2);
6834 /* The rules for pointers to members A::* are just like the rules
6835 for pointers A*, except opposite: if B is derived from A then
6836 A::* converts to B::*, not vice versa. For that reason, we
6837 switch the from_ and to_ variables here. */
6838 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6839 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6840 || (TYPE_PTRMEMFUNC_P (from_type1)
6841 && TYPE_PTRMEMFUNC_P (from_type2)
6842 && TYPE_PTRMEMFUNC_P (to_type1)
6843 && TYPE_PTRMEMFUNC_P (to_type2)))
6845 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6846 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6847 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6848 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6851 if (deref_from_type1 != NULL_TREE
6852 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6853 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6855 /* This was one of the pointer or pointer-like conversions.
6859 --If class B is derived directly or indirectly from class A,
6860 conversion of B* to A* is better than conversion of B* to
6861 void*, and conversion of A* to void* is better than
6862 conversion of B* to void*. */
6863 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6864 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6866 if (is_properly_derived_from (deref_from_type1,
6869 else if (is_properly_derived_from (deref_from_type2,
6873 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6874 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6876 if (same_type_p (deref_from_type1, deref_from_type2))
6878 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6880 if (is_properly_derived_from (deref_from_type1,
6884 /* We know that DEREF_TO_TYPE1 is `void' here. */
6885 else if (is_properly_derived_from (deref_from_type1,
6890 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6891 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6895 --If class B is derived directly or indirectly from class A
6896 and class C is derived directly or indirectly from B,
6898 --conversion of C* to B* is better than conversion of C* to
6901 --conversion of B* to A* is better than conversion of C* to
6903 if (same_type_p (deref_from_type1, deref_from_type2))
6905 if (is_properly_derived_from (deref_to_type1,
6908 else if (is_properly_derived_from (deref_to_type2,
6912 else if (same_type_p (deref_to_type1, deref_to_type2))
6914 if (is_properly_derived_from (deref_from_type2,
6917 else if (is_properly_derived_from (deref_from_type1,
6923 else if (CLASS_TYPE_P (non_reference (from_type1))
6924 && same_type_p (from_type1, from_type2))
6926 tree from = non_reference (from_type1);
6930 --binding of an expression of type C to a reference of type
6931 B& is better than binding an expression of type C to a
6932 reference of type A&
6934 --conversion of C to B is better than conversion of C to A, */
6935 if (is_properly_derived_from (from, to_type1)
6936 && is_properly_derived_from (from, to_type2))
6938 if (is_properly_derived_from (to_type1, to_type2))
6940 else if (is_properly_derived_from (to_type2, to_type1))
6944 else if (CLASS_TYPE_P (non_reference (to_type1))
6945 && same_type_p (to_type1, to_type2))
6947 tree to = non_reference (to_type1);
6951 --binding of an expression of type B to a reference of type
6952 A& is better than binding an expression of type C to a
6953 reference of type A&,
6955 --conversion of B to A is better than conversion of C to A */
6956 if (is_properly_derived_from (from_type1, to)
6957 && is_properly_derived_from (from_type2, to))
6959 if (is_properly_derived_from (from_type2, from_type1))
6961 else if (is_properly_derived_from (from_type1, from_type2))
6968 --S1 and S2 differ only in their qualification conversion and yield
6969 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6970 qualification signature of type T1 is a proper subset of the cv-
6971 qualification signature of type T2 */
6972 if (ics1->kind == ck_qual
6973 && ics2->kind == ck_qual
6974 && same_type_p (from_type1, from_type2))
6976 int result = comp_cv_qual_signature (to_type1, to_type2);
6983 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6984 to an implicit object parameter, and either S1 binds an lvalue reference
6985 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6986 reference to an rvalue and S2 binds an lvalue reference
6987 (C++0x draft standard, 13.3.3.2)
6989 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6990 types to which the references refer are the same type except for
6991 top-level cv-qualifiers, and the type to which the reference
6992 initialized by S2 refers is more cv-qualified than the type to
6993 which the reference initialized by S1 refers */
6995 if (ref_conv1 && ref_conv2)
6997 if (!ref_conv1->this_p && !ref_conv2->this_p
6998 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6999 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
7001 if (ref_conv1->rvaluedness_matches_p)
7003 if (ref_conv2->rvaluedness_matches_p)
7007 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7008 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7009 TREE_TYPE (ref_conv1->type));
7012 /* Neither conversion sequence is better than the other. */
7016 /* The source type for this standard conversion sequence. */
7019 source_type (conversion *t)
7021 for (;; t = t->u.next)
7023 if (t->kind == ck_user
7024 || t->kind == ck_ambig
7025 || t->kind == ck_identity)
7031 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7032 a pointer to LOSER and re-running joust to produce the warning if WINNER
7033 is actually used. */
7036 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7038 candidate_warning *cw = (candidate_warning *)
7039 conversion_obstack_alloc (sizeof (candidate_warning));
7041 cw->next = winner->warnings;
7042 winner->warnings = cw;
7045 /* Compare two candidates for overloading as described in
7046 [over.match.best]. Return values:
7048 1: cand1 is better than cand2
7049 -1: cand2 is better than cand1
7050 0: cand1 and cand2 are indistinguishable */
7053 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7056 int off1 = 0, off2 = 0;
7060 /* Candidates that involve bad conversions are always worse than those
7062 if (cand1->viable > cand2->viable)
7064 if (cand1->viable < cand2->viable)
7067 /* If we have two pseudo-candidates for conversions to the same type,
7068 or two candidates for the same function, arbitrarily pick one. */
7069 if (cand1->fn == cand2->fn
7070 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7073 /* a viable function F1
7074 is defined to be a better function than another viable function F2 if
7075 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7076 ICSi(F2), and then */
7078 /* for some argument j, ICSj(F1) is a better conversion sequence than
7081 /* For comparing static and non-static member functions, we ignore
7082 the implicit object parameter of the non-static function. The
7083 standard says to pretend that the static function has an object
7084 parm, but that won't work with operator overloading. */
7085 len = cand1->num_convs;
7086 if (len != cand2->num_convs)
7088 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7089 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7091 gcc_assert (static_1 != static_2);
7102 for (i = 0; i < len; ++i)
7104 conversion *t1 = cand1->convs[i + off1];
7105 conversion *t2 = cand2->convs[i + off2];
7106 int comp = compare_ics (t1, t2);
7111 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7112 == cr_std + cr_promotion)
7113 && t1->kind == ck_std
7114 && t2->kind == ck_std
7115 && TREE_CODE (t1->type) == INTEGER_TYPE
7116 && TREE_CODE (t2->type) == INTEGER_TYPE
7117 && (TYPE_PRECISION (t1->type)
7118 == TYPE_PRECISION (t2->type))
7119 && (TYPE_UNSIGNED (t1->u.next->type)
7120 || (TREE_CODE (t1->u.next->type)
7123 tree type = t1->u.next->type;
7125 struct z_candidate *w, *l;
7127 type1 = t1->type, type2 = t2->type,
7128 w = cand1, l = cand2;
7130 type1 = t2->type, type2 = t1->type,
7131 w = cand2, l = cand1;
7135 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7136 type, type1, type2);
7137 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7143 if (winner && comp != winner)
7152 /* warn about confusing overload resolution for user-defined conversions,
7153 either between a constructor and a conversion op, or between two
7155 if (winner && warn_conversion && cand1->second_conv
7156 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7157 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7159 struct z_candidate *w, *l;
7160 bool give_warning = false;
7163 w = cand1, l = cand2;
7165 w = cand2, l = cand1;
7167 /* We don't want to complain about `X::operator T1 ()'
7168 beating `X::operator T2 () const', when T2 is a no less
7169 cv-qualified version of T1. */
7170 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7171 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7173 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7174 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7176 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7181 if (!comp_ptr_ttypes (t, f))
7182 give_warning = true;
7185 give_warning = true;
7191 tree source = source_type (w->convs[0]);
7192 if (! DECL_CONSTRUCTOR_P (w->fn))
7193 source = TREE_TYPE (source);
7194 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7195 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7196 source, w->second_conv->type))
7198 inform (input_location, " because conversion sequence for the argument is better");
7209 F1 is a non-template function and F2 is a template function
7212 if (!cand1->template_decl && cand2->template_decl)
7214 else if (cand1->template_decl && !cand2->template_decl)
7218 F1 and F2 are template functions and the function template for F1 is
7219 more specialized than the template for F2 according to the partial
7222 if (cand1->template_decl && cand2->template_decl)
7224 winner = more_specialized_fn
7225 (TI_TEMPLATE (cand1->template_decl),
7226 TI_TEMPLATE (cand2->template_decl),
7227 /* [temp.func.order]: The presence of unused ellipsis and default
7228 arguments has no effect on the partial ordering of function
7229 templates. add_function_candidate() will not have
7230 counted the "this" argument for constructors. */
7231 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7237 the context is an initialization by user-defined conversion (see
7238 _dcl.init_ and _over.match.user_) and the standard conversion
7239 sequence from the return type of F1 to the destination type (i.e.,
7240 the type of the entity being initialized) is a better conversion
7241 sequence than the standard conversion sequence from the return type
7242 of F2 to the destination type. */
7244 if (cand1->second_conv)
7246 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7251 /* Check whether we can discard a builtin candidate, either because we
7252 have two identical ones or matching builtin and non-builtin candidates.
7254 (Pedantically in the latter case the builtin which matched the user
7255 function should not be added to the overload set, but we spot it here.
7258 ... the builtin candidates include ...
7259 - do not have the same parameter type list as any non-template
7260 non-member candidate. */
7262 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7263 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7265 for (i = 0; i < len; ++i)
7266 if (!same_type_p (cand1->convs[i]->type,
7267 cand2->convs[i]->type))
7269 if (i == cand1->num_convs)
7271 if (cand1->fn == cand2->fn)
7272 /* Two built-in candidates; arbitrarily pick one. */
7274 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7275 /* cand1 is built-in; prefer cand2. */
7278 /* cand2 is built-in; prefer cand1. */
7283 /* If the two function declarations represent the same function (this can
7284 happen with declarations in multiple scopes and arg-dependent lookup),
7285 arbitrarily choose one. But first make sure the default args we're
7287 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7288 && equal_functions (cand1->fn, cand2->fn))
7290 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7291 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7293 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7295 for (i = 0; i < len; ++i)
7297 /* Don't crash if the fn is variadic. */
7300 parms1 = TREE_CHAIN (parms1);
7301 parms2 = TREE_CHAIN (parms2);
7305 parms1 = TREE_CHAIN (parms1);
7307 parms2 = TREE_CHAIN (parms2);
7311 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7312 TREE_PURPOSE (parms2)))
7316 permerror (input_location, "default argument mismatch in "
7317 "overload resolution");
7318 inform (input_location,
7319 " candidate 1: %q+#F", cand1->fn);
7320 inform (input_location,
7321 " candidate 2: %q+#F", cand2->fn);
7324 add_warning (cand1, cand2);
7327 parms1 = TREE_CHAIN (parms1);
7328 parms2 = TREE_CHAIN (parms2);
7336 /* Extension: If the worst conversion for one candidate is worse than the
7337 worst conversion for the other, take the first. */
7340 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7341 struct z_candidate *w = 0, *l = 0;
7343 for (i = 0; i < len; ++i)
7345 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7346 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7347 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7348 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7351 winner = 1, w = cand1, l = cand2;
7353 winner = -1, w = cand2, l = cand1;
7358 pedwarn (input_location, 0,
7359 "ISO C++ says that these are ambiguous, even "
7360 "though the worst conversion for the first is better than "
7361 "the worst conversion for the second:");
7362 print_z_candidate (_("candidate 1:"), w);
7363 print_z_candidate (_("candidate 2:"), l);
7371 gcc_assert (!winner);
7375 /* Given a list of candidates for overloading, find the best one, if any.
7376 This algorithm has a worst case of O(2n) (winner is last), and a best
7377 case of O(n/2) (totally ambiguous); much better than a sorting
7380 static struct z_candidate *
7381 tourney (struct z_candidate *candidates)
7383 struct z_candidate *champ = candidates, *challenger;
7385 int champ_compared_to_predecessor = 0;
7387 /* Walk through the list once, comparing each current champ to the next
7388 candidate, knocking out a candidate or two with each comparison. */
7390 for (challenger = champ->next; challenger; )
7392 fate = joust (champ, challenger, 0);
7394 challenger = challenger->next;
7399 champ = challenger->next;
7402 champ_compared_to_predecessor = 0;
7407 champ_compared_to_predecessor = 1;
7410 challenger = champ->next;
7414 /* Make sure the champ is better than all the candidates it hasn't yet
7415 been compared to. */
7417 for (challenger = candidates;
7419 && !(champ_compared_to_predecessor && challenger->next == champ);
7420 challenger = challenger->next)
7422 fate = joust (champ, challenger, 0);
7430 /* Returns nonzero if things of type FROM can be converted to TO. */
7433 can_convert (tree to, tree from)
7435 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7438 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7441 can_convert_arg (tree to, tree from, tree arg, int flags)
7447 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7448 p = conversion_obstack_alloc (0);
7450 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7452 ok_p = (t && !t->bad_p);
7454 /* Free all the conversions we allocated. */
7455 obstack_free (&conversion_obstack, p);
7460 /* Like can_convert_arg, but allows dubious conversions as well. */
7463 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7468 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7469 p = conversion_obstack_alloc (0);
7470 /* Try to perform the conversion. */
7471 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7473 /* Free all the conversions we allocated. */
7474 obstack_free (&conversion_obstack, p);
7479 /* Convert EXPR to TYPE. Return the converted expression.
7481 Note that we allow bad conversions here because by the time we get to
7482 this point we are committed to doing the conversion. If we end up
7483 doing a bad conversion, convert_like will complain. */
7486 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7491 if (error_operand_p (expr))
7492 return error_mark_node;
7494 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7495 p = conversion_obstack_alloc (0);
7497 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7503 if (complain & tf_error)
7505 /* If expr has unknown type, then it is an overloaded function.
7506 Call instantiate_type to get good error messages. */
7507 if (TREE_TYPE (expr) == unknown_type_node)
7508 instantiate_type (type, expr, complain);
7509 else if (invalid_nonstatic_memfn_p (expr, complain))
7510 /* We gave an error. */;
7512 error ("could not convert %qE to %qT", expr, type);
7514 expr = error_mark_node;
7516 else if (processing_template_decl)
7518 /* In a template, we are only concerned about determining the
7519 type of non-dependent expressions, so we do not have to
7520 perform the actual conversion. */
7521 if (TREE_TYPE (expr) != type)
7522 expr = build_nop (type, expr);
7525 expr = convert_like (conv, expr, complain);
7527 /* Free all the conversions we allocated. */
7528 obstack_free (&conversion_obstack, p);
7534 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7536 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7539 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7540 permitted. If the conversion is valid, the converted expression is
7541 returned. Otherwise, NULL_TREE is returned, except in the case
7542 that TYPE is a class type; in that case, an error is issued. If
7543 C_CAST_P is true, then this direction initialization is taking
7544 place as part of a static_cast being attempted as part of a C-style
7548 perform_direct_initialization_if_possible (tree type,
7551 tsubst_flags_t complain)
7556 if (type == error_mark_node || error_operand_p (expr))
7557 return error_mark_node;
7560 If the destination type is a (possibly cv-qualified) class type:
7562 -- If the initialization is direct-initialization ...,
7563 constructors are considered. ... If no constructor applies, or
7564 the overload resolution is ambiguous, the initialization is
7566 if (CLASS_TYPE_P (type))
7568 VEC(tree,gc) *args = make_tree_vector_single (expr);
7569 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7570 &args, type, LOOKUP_NORMAL, complain);
7571 release_tree_vector (args);
7572 return build_cplus_new (type, expr);
7575 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7576 p = conversion_obstack_alloc (0);
7578 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7581 if (!conv || conv->bad_p)
7584 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7585 /*issue_conversion_warnings=*/false,
7587 tf_warning_or_error);
7589 /* Free all the conversions we allocated. */
7590 obstack_free (&conversion_obstack, p);
7595 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7596 is being bound to a temporary. Create and return a new VAR_DECL
7597 with the indicated TYPE; this variable will store the value to
7598 which the reference is bound. */
7601 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7605 /* Create the variable. */
7606 var = create_temporary_var (type);
7608 /* Register the variable. */
7609 if (TREE_STATIC (decl))
7611 /* Namespace-scope or local static; give it a mangled name. */
7614 TREE_STATIC (var) = 1;
7615 name = mangle_ref_init_variable (decl);
7616 DECL_NAME (var) = name;
7617 SET_DECL_ASSEMBLER_NAME (var, name);
7618 var = pushdecl_top_level (var);
7621 /* Create a new cleanup level if necessary. */
7622 maybe_push_cleanup_level (type);
7627 /* EXPR is the initializer for a variable DECL of reference or
7628 std::initializer_list type. Create, push and return a new VAR_DECL
7629 for the initializer so that it will live as long as DECL. Any
7630 cleanup for the new variable is returned through CLEANUP, and the
7631 code to initialize the new variable is returned through INITP. */
7634 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7640 /* Create the temporary variable. */
7641 type = TREE_TYPE (expr);
7642 var = make_temporary_var_for_ref_to_temp (decl, type);
7643 layout_decl (var, 0);
7644 /* If the rvalue is the result of a function call it will be
7645 a TARGET_EXPR. If it is some other construct (such as a
7646 member access expression where the underlying object is
7647 itself the result of a function call), turn it into a
7648 TARGET_EXPR here. It is important that EXPR be a
7649 TARGET_EXPR below since otherwise the INIT_EXPR will
7650 attempt to make a bitwise copy of EXPR to initialize
7652 if (TREE_CODE (expr) != TARGET_EXPR)
7653 expr = get_target_expr (expr);
7654 /* Create the INIT_EXPR that will initialize the temporary
7656 init = build2 (INIT_EXPR, type, var, expr);
7657 if (at_function_scope_p ())
7659 add_decl_expr (var);
7661 if (TREE_STATIC (var))
7662 init = add_stmt_to_compound (init, register_dtor_fn (var));
7664 *cleanup = cxx_maybe_build_cleanup (var);
7666 /* We must be careful to destroy the temporary only
7667 after its initialization has taken place. If the
7668 initialization throws an exception, then the
7669 destructor should not be run. We cannot simply
7670 transform INIT into something like:
7672 (INIT, ({ CLEANUP_STMT; }))
7674 because emit_local_var always treats the
7675 initializer as a full-expression. Thus, the
7676 destructor would run too early; it would run at the
7677 end of initializing the reference variable, rather
7678 than at the end of the block enclosing the
7681 The solution is to pass back a cleanup expression
7682 which the caller is responsible for attaching to
7683 the statement tree. */
7687 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7688 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7689 static_aggregates = tree_cons (NULL_TREE, var,
7697 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7698 initializing a variable of that TYPE. If DECL is non-NULL, it is
7699 the VAR_DECL being initialized with the EXPR. (In that case, the
7700 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7701 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7702 return, if *CLEANUP is no longer NULL, it will be an expression
7703 that should be pushed as a cleanup after the returned expression
7704 is used to initialize DECL.
7706 Return the converted expression. */
7709 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
7710 tsubst_flags_t complain)
7715 if (type == error_mark_node || error_operand_p (expr))
7716 return error_mark_node;
7718 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7719 p = conversion_obstack_alloc (0);
7721 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7723 if (!conv || conv->bad_p)
7725 if (complain & tf_error)
7727 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7728 && !TYPE_REF_IS_RVALUE (type)
7729 && !real_lvalue_p (expr))
7730 error ("invalid initialization of non-const reference of "
7731 "type %qT from an rvalue of type %qT",
7732 type, TREE_TYPE (expr));
7734 error ("invalid initialization of reference of type "
7735 "%qT from expression of type %qT", type,
7738 return error_mark_node;
7741 /* If DECL is non-NULL, then this special rule applies:
7745 The temporary to which the reference is bound or the temporary
7746 that is the complete object to which the reference is bound
7747 persists for the lifetime of the reference.
7749 The temporaries created during the evaluation of the expression
7750 initializing the reference, except the temporary to which the
7751 reference is bound, are destroyed at the end of the
7752 full-expression in which they are created.
7754 In that case, we store the converted expression into a new
7755 VAR_DECL in a new scope.
7757 However, we want to be careful not to create temporaries when
7758 they are not required. For example, given:
7761 struct D : public B {};
7765 there is no need to copy the return value from "f"; we can just
7766 extend its lifetime. Similarly, given:
7769 struct T { operator S(); };
7773 we can extend the lifetime of the return value of the conversion
7775 gcc_assert (conv->kind == ck_ref_bind);
7779 tree base_conv_type;
7781 /* Skip over the REF_BIND. */
7782 conv = conv->u.next;
7783 /* If the next conversion is a BASE_CONV, skip that too -- but
7784 remember that the conversion was required. */
7785 if (conv->kind == ck_base)
7787 base_conv_type = conv->type;
7788 conv = conv->u.next;
7791 base_conv_type = NULL_TREE;
7792 /* Perform the remainder of the conversion. */
7793 expr = convert_like_real (conv, expr,
7794 /*fn=*/NULL_TREE, /*argnum=*/0,
7796 /*issue_conversion_warnings=*/true,
7798 tf_warning_or_error);
7799 if (error_operand_p (expr))
7800 expr = error_mark_node;
7803 if (!lvalue_or_rvalue_with_address_p (expr))
7806 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7807 /* Use its address to initialize the reference variable. */
7808 expr = build_address (var);
7810 expr = convert_to_base (expr,
7811 build_pointer_type (base_conv_type),
7812 /*check_access=*/true,
7814 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7817 /* Take the address of EXPR. */
7818 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7819 /* If a BASE_CONV was required, perform it now. */
7821 expr = (perform_implicit_conversion
7822 (build_pointer_type (base_conv_type), expr,
7823 tf_warning_or_error));
7824 expr = build_nop (type, expr);
7828 /* Perform the conversion. */
7829 expr = convert_like (conv, expr, tf_warning_or_error);
7831 /* Free all the conversions we allocated. */
7832 obstack_free (&conversion_obstack, p);
7837 /* Returns true iff TYPE is some variant of std::initializer_list. */
7840 is_std_init_list (tree type)
7842 return (CLASS_TYPE_P (type)
7843 && CP_TYPE_CONTEXT (type) == std_node
7844 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7847 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7848 will accept an argument list of a single std::initializer_list<T>. */
7851 is_list_ctor (tree decl)
7853 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7856 if (!args || args == void_list_node)
7859 arg = non_reference (TREE_VALUE (args));
7860 if (!is_std_init_list (arg))
7863 args = TREE_CHAIN (args);
7865 if (args && args != void_list_node && !TREE_PURPOSE (args))
7866 /* There are more non-defaulted parms. */
7872 #include "gt-cp-call.h"