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 = TYPE_FIELDS (type);
631 for (; field; field = TREE_CHAIN (field), ++i)
633 if (TREE_CODE (field) != FIELD_DECL)
635 if (i < CONSTRUCTOR_NELTS (ctor))
637 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
638 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
642 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
646 c = alloc_conversion (ck_aggr);
649 c->user_conv_p = true;
654 /* Build a representation of the identity conversion from EXPR to
655 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
658 build_identity_conv (tree type, tree expr)
662 c = alloc_conversion (ck_identity);
669 /* Converting from EXPR to TYPE was ambiguous in the sense that there
670 were multiple user-defined conversions to accomplish the job.
671 Build a conversion that indicates that ambiguity. */
674 build_ambiguous_conv (tree type, tree expr)
678 c = alloc_conversion (ck_ambig);
686 strip_top_quals (tree t)
688 if (TREE_CODE (t) == ARRAY_TYPE)
690 return cp_build_qualified_type (t, 0);
693 /* Returns the standard conversion path (see [conv]) from type FROM to type
694 TO, if any. For proper handling of null pointer constants, you must
695 also pass the expression EXPR to convert from. If C_CAST_P is true,
696 this conversion is coming from a C-style cast. */
699 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
702 enum tree_code fcode, tcode;
704 bool fromref = false;
706 to = non_reference (to);
707 if (TREE_CODE (from) == REFERENCE_TYPE)
710 from = TREE_TYPE (from);
712 to = strip_top_quals (to);
713 from = strip_top_quals (from);
715 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
716 && expr && type_unknown_p (expr))
718 tsubst_flags_t tflags = tf_conv;
719 if (!(flags & LOOKUP_PROTECT))
720 tflags |= tf_no_access_control;
721 expr = instantiate_type (to, expr, tflags);
722 if (expr == error_mark_node)
724 from = TREE_TYPE (expr);
727 fcode = TREE_CODE (from);
728 tcode = TREE_CODE (to);
730 conv = build_identity_conv (from, expr);
731 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
733 from = type_decays_to (from);
734 fcode = TREE_CODE (from);
735 conv = build_conv (ck_lvalue, from, conv);
737 else if (fromref || (expr && lvalue_p (expr)))
742 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
745 from = strip_top_quals (bitfield_type);
746 fcode = TREE_CODE (from);
749 conv = build_conv (ck_rvalue, from, conv);
752 /* Allow conversion between `__complex__' data types. */
753 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
755 /* The standard conversion sequence to convert FROM to TO is
756 the standard conversion sequence to perform componentwise
758 conversion *part_conv = standard_conversion
759 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
763 conv = build_conv (part_conv->kind, to, conv);
764 conv->rank = part_conv->rank;
772 if (same_type_p (from, to))
775 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
776 && expr && null_ptr_cst_p (expr))
777 conv = build_conv (ck_std, to, conv);
778 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
779 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
781 /* For backwards brain damage compatibility, allow interconversion of
782 pointers and integers with a pedwarn. */
783 conv = build_conv (ck_std, to, conv);
786 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
788 /* For backwards brain damage compatibility, allow interconversion of
789 enums and integers with a pedwarn. */
790 conv = build_conv (ck_std, to, conv);
793 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
794 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
799 if (tcode == POINTER_TYPE
800 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
803 else if (VOID_TYPE_P (TREE_TYPE (to))
804 && !TYPE_PTRMEM_P (from)
805 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
807 from = build_pointer_type
808 (cp_build_qualified_type (void_type_node,
809 cp_type_quals (TREE_TYPE (from))));
810 conv = build_conv (ck_ptr, from, conv);
812 else if (TYPE_PTRMEM_P (from))
814 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
815 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
817 if (DERIVED_FROM_P (fbase, tbase)
818 && (same_type_ignoring_top_level_qualifiers_p
819 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
820 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
822 from = build_ptrmem_type (tbase,
823 TYPE_PTRMEM_POINTED_TO_TYPE (from));
824 conv = build_conv (ck_pmem, from, conv);
826 else if (!same_type_p (fbase, tbase))
829 else if (CLASS_TYPE_P (TREE_TYPE (from))
830 && CLASS_TYPE_P (TREE_TYPE (to))
833 An rvalue of type "pointer to cv D," where D is a
834 class type, can be converted to an rvalue of type
835 "pointer to cv B," where B is a base class (clause
836 _class.derived_) of D. If B is an inaccessible
837 (clause _class.access_) or ambiguous
838 (_class.member.lookup_) base class of D, a program
839 that necessitates this conversion is ill-formed.
840 Therefore, we use DERIVED_FROM_P, and do not check
841 access or uniqueness. */
842 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
845 cp_build_qualified_type (TREE_TYPE (to),
846 cp_type_quals (TREE_TYPE (from)));
847 from = build_pointer_type (from);
848 conv = build_conv (ck_ptr, from, conv);
852 if (tcode == POINTER_TYPE)
854 to_pointee = TREE_TYPE (to);
855 from_pointee = TREE_TYPE (from);
859 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
860 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
863 if (same_type_p (from, to))
865 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
866 /* In a C-style cast, we ignore CV-qualification because we
867 are allowed to perform a static_cast followed by a
869 conv = build_conv (ck_qual, to, conv);
870 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
871 conv = build_conv (ck_qual, to, conv);
872 else if (expr && string_conv_p (to, expr, 0))
873 /* converting from string constant to char *. */
874 conv = build_conv (ck_qual, to, conv);
875 else if (ptr_reasonably_similar (to_pointee, from_pointee))
877 conv = build_conv (ck_ptr, to, conv);
885 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
887 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
888 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
889 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
890 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
892 if (!DERIVED_FROM_P (fbase, tbase)
893 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
894 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
895 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
896 || cp_type_quals (fbase) != cp_type_quals (tbase))
899 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
900 from = build_ptrmemfunc_type (build_pointer_type (from));
901 conv = build_conv (ck_pmem, from, conv);
904 else if (tcode == BOOLEAN_TYPE)
908 An rvalue of arithmetic, unscoped enumeration, pointer, or
909 pointer to member type can be converted to an rvalue of type
911 if (ARITHMETIC_TYPE_P (from)
912 || UNSCOPED_ENUM_P (from)
913 || fcode == POINTER_TYPE
914 || TYPE_PTR_TO_MEMBER_P (from))
916 conv = build_conv (ck_std, to, conv);
917 if (fcode == POINTER_TYPE
918 || TYPE_PTRMEM_P (from)
919 || (TYPE_PTRMEMFUNC_P (from)
920 && conv->rank < cr_pbool))
921 conv->rank = cr_pbool;
927 /* We don't check for ENUMERAL_TYPE here because there are no standard
928 conversions to enum type. */
929 /* As an extension, allow conversion to complex type. */
930 else if (ARITHMETIC_TYPE_P (to))
932 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
933 || SCOPED_ENUM_P (from))
935 conv = build_conv (ck_std, to, conv);
937 /* Give this a better rank if it's a promotion. */
938 if (same_type_p (to, type_promotes_to (from))
939 && conv->u.next->rank <= cr_promotion)
940 conv->rank = cr_promotion;
942 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
943 && vector_types_convertible_p (from, to, false))
944 return build_conv (ck_std, to, conv);
945 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
946 && is_properly_derived_from (from, to))
948 if (conv->kind == ck_rvalue)
950 conv = build_conv (ck_base, to, conv);
951 /* The derived-to-base conversion indicates the initialization
952 of a parameter with base type from an object of a derived
953 type. A temporary object is created to hold the result of
954 the conversion unless we're binding directly to a reference. */
955 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
960 if (flags & LOOKUP_NO_NARROWING)
961 conv->check_narrowing = true;
966 /* Returns nonzero if T1 is reference-related to T2. */
969 reference_related_p (tree t1, tree t2)
971 t1 = TYPE_MAIN_VARIANT (t1);
972 t2 = TYPE_MAIN_VARIANT (t2);
976 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
977 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
979 return (same_type_p (t1, t2)
980 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
981 && DERIVED_FROM_P (t1, t2)));
984 /* Returns nonzero if T1 is reference-compatible with T2. */
987 reference_compatible_p (tree t1, tree t2)
991 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
992 reference-related to T2 and cv1 is the same cv-qualification as,
993 or greater cv-qualification than, cv2. */
994 return (reference_related_p (t1, t2)
995 && at_least_as_qualified_p (t1, t2));
998 /* Determine whether or not the EXPR (of class type S) can be
999 converted to T as in [over.match.ref]. */
1002 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1008 struct z_candidate *candidates;
1009 struct z_candidate *cand;
1012 conversions = lookup_conversions (s);
1018 Assuming that "cv1 T" is the underlying type of the reference
1019 being initialized, and "cv S" is the type of the initializer
1020 expression, with S a class type, the candidate functions are
1021 selected as follows:
1023 --The conversion functions of S and its base classes are
1024 considered. Those that are not hidden within S and yield type
1025 "reference to cv2 T2", where "cv1 T" is reference-compatible
1026 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1028 The argument list has one argument, which is the initializer
1033 /* Conceptually, we should take the address of EXPR and put it in
1034 the argument list. Unfortunately, however, that can result in
1035 error messages, which we should not issue now because we are just
1036 trying to find a conversion operator. Therefore, we use NULL,
1037 cast to the appropriate type. */
1038 first_arg = build_int_cst (build_pointer_type (s), 0);
1040 t = TREE_TYPE (reference_type);
1042 for (; conversions; conversions = TREE_CHAIN (conversions))
1044 tree fns = TREE_VALUE (conversions);
1046 for (; fns; fns = OVL_NEXT (fns))
1048 tree f = OVL_CURRENT (fns);
1049 tree t2 = TREE_TYPE (TREE_TYPE (f));
1051 if (DECL_NONCONVERTING_P (f)
1052 && (flags & LOOKUP_ONLYCONVERTING))
1057 /* If this is a template function, try to get an exact
1059 if (TREE_CODE (f) == TEMPLATE_DECL)
1061 cand = add_template_candidate (&candidates,
1068 TREE_PURPOSE (conversions),
1074 /* Now, see if the conversion function really returns
1075 an lvalue of the appropriate type. From the
1076 point of view of unification, simply returning an
1077 rvalue of the right type is good enough. */
1079 t2 = TREE_TYPE (TREE_TYPE (f));
1080 if (TREE_CODE (t2) != REFERENCE_TYPE
1081 || !reference_compatible_p (t, TREE_TYPE (t2)))
1083 candidates = candidates->next;
1088 else if (TREE_CODE (t2) == REFERENCE_TYPE
1089 && reference_compatible_p (t, TREE_TYPE (t2)))
1090 cand = add_function_candidate (&candidates, f, s, first_arg,
1091 NULL, TYPE_BINFO (s),
1092 TREE_PURPOSE (conversions),
1097 conversion *identity_conv;
1098 /* Build a standard conversion sequence indicating the
1099 binding from the reference type returned by the
1100 function to the desired REFERENCE_TYPE. */
1102 = build_identity_conv (TREE_TYPE (TREE_TYPE
1103 (TREE_TYPE (cand->fn))),
1106 = (direct_reference_binding
1107 (reference_type, identity_conv));
1108 cand->second_conv->rvaluedness_matches_p
1109 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1110 == TYPE_REF_IS_RVALUE (reference_type);
1111 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1113 /* Don't allow binding of lvalues to rvalue references. */
1114 if (TYPE_REF_IS_RVALUE (reference_type)
1115 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1116 cand->second_conv->bad_p = true;
1121 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1122 /* If none of the conversion functions worked out, let our caller
1127 cand = tourney (candidates);
1131 /* Now that we know that this is the function we're going to use fix
1132 the dummy first argument. */
1133 gcc_assert (cand->first_arg == NULL_TREE
1134 || integer_zerop (cand->first_arg));
1135 cand->first_arg = build_this (expr);
1137 /* Build a user-defined conversion sequence representing the
1139 conv = build_conv (ck_user,
1140 TREE_TYPE (TREE_TYPE (cand->fn)),
1141 build_identity_conv (TREE_TYPE (expr), expr));
1144 if (cand->viable == -1)
1147 /* Merge it with the standard conversion sequence from the
1148 conversion function's return type to the desired type. */
1149 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1151 return cand->second_conv;
1154 /* A reference of the indicated TYPE is being bound directly to the
1155 expression represented by the implicit conversion sequence CONV.
1156 Return a conversion sequence for this binding. */
1159 direct_reference_binding (tree type, conversion *conv)
1163 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1164 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1166 t = TREE_TYPE (type);
1170 When a parameter of reference type binds directly
1171 (_dcl.init.ref_) to an argument expression, the implicit
1172 conversion sequence is the identity conversion, unless the
1173 argument expression has a type that is a derived class of the
1174 parameter type, in which case the implicit conversion sequence is
1175 a derived-to-base Conversion.
1177 If the parameter binds directly to the result of applying a
1178 conversion function to the argument expression, the implicit
1179 conversion sequence is a user-defined conversion sequence
1180 (_over.ics.user_), with the second standard conversion sequence
1181 either an identity conversion or, if the conversion function
1182 returns an entity of a type that is a derived class of the
1183 parameter type, a derived-to-base conversion. */
1184 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1186 /* Represent the derived-to-base conversion. */
1187 conv = build_conv (ck_base, t, conv);
1188 /* We will actually be binding to the base-class subobject in
1189 the derived class, so we mark this conversion appropriately.
1190 That way, convert_like knows not to generate a temporary. */
1191 conv->need_temporary_p = false;
1193 return build_conv (ck_ref_bind, type, conv);
1196 /* Returns the conversion path from type FROM to reference type TO for
1197 purposes of reference binding. For lvalue binding, either pass a
1198 reference type to FROM or an lvalue expression to EXPR. If the
1199 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1200 the conversion returned. If C_CAST_P is true, this
1201 conversion is coming from a C-style cast. */
1204 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1206 conversion *conv = NULL;
1207 tree to = TREE_TYPE (rto);
1212 cp_lvalue_kind is_lvalue = clk_none;
1214 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1216 expr = instantiate_type (to, expr, tf_none);
1217 if (expr == error_mark_node)
1219 from = TREE_TYPE (expr);
1222 if (TREE_CODE (from) == REFERENCE_TYPE)
1224 /* Anything with reference type is an lvalue. */
1225 is_lvalue = clk_ordinary;
1226 from = TREE_TYPE (from);
1229 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1231 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1232 conv = implicit_conversion (to, from, expr, c_cast_p,
1234 if (!CLASS_TYPE_P (to)
1235 && CONSTRUCTOR_NELTS (expr) == 1)
1237 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1238 if (error_operand_p (expr))
1240 from = TREE_TYPE (expr);
1244 if (is_lvalue == clk_none && expr)
1245 is_lvalue = real_lvalue_p (expr);
1248 if ((is_lvalue & clk_bitfield) != 0)
1249 tfrom = unlowered_expr_type (expr);
1251 /* Figure out whether or not the types are reference-related and
1252 reference compatible. We have do do this after stripping
1253 references from FROM. */
1254 related_p = reference_related_p (to, tfrom);
1255 /* If this is a C cast, first convert to an appropriately qualified
1256 type, so that we can later do a const_cast to the desired type. */
1257 if (related_p && c_cast_p
1258 && !at_least_as_qualified_p (to, tfrom))
1259 to = build_qualified_type (to, cp_type_quals (tfrom));
1260 compatible_p = reference_compatible_p (to, tfrom);
1262 /* Directly bind reference when target expression's type is compatible with
1263 the reference and expression is an lvalue. In DR391, the wording in
1264 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1265 const and rvalue references to rvalues of compatible class type.
1266 We should also do direct bindings for non-class "rvalues" derived from
1267 rvalue references. */
1270 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1271 && !(flags & LOOKUP_NO_TEMP_BIND))
1272 || TYPE_REF_IS_RVALUE (rto))
1273 && (CLASS_TYPE_P (from) || (expr && lvalue_p (expr))))))
1277 If the initializer expression
1279 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1280 is reference-compatible with "cv2 T2,"
1282 the reference is bound directly to the initializer expression
1286 If the initializer expression is an rvalue, with T2 a class type,
1287 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1288 is bound to the object represented by the rvalue or to a sub-object
1289 within that object. */
1291 conv = build_identity_conv (tfrom, expr);
1292 conv = direct_reference_binding (rto, conv);
1294 if (flags & LOOKUP_PREFER_RVALUE)
1295 /* The top-level caller requested that we pretend that the lvalue
1296 be treated as an rvalue. */
1297 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1299 conv->rvaluedness_matches_p
1300 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1302 if ((is_lvalue & clk_bitfield) != 0
1303 || ((is_lvalue & clk_packed) != 0 && !TYPE_PACKED (to)))
1304 /* For the purposes of overload resolution, we ignore the fact
1305 this expression is a bitfield or packed field. (In particular,
1306 [over.ics.ref] says specifically that a function with a
1307 non-const reference parameter is viable even if the
1308 argument is a bitfield.)
1310 However, when we actually call the function we must create
1311 a temporary to which to bind the reference. If the
1312 reference is volatile, or isn't const, then we cannot make
1313 a temporary, so we just issue an error when the conversion
1315 conv->need_temporary_p = true;
1317 /* Don't allow binding of lvalues to rvalue references. */
1318 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1319 && !(flags & LOOKUP_PREFER_RVALUE))
1324 /* [class.conv.fct] A conversion function is never used to convert a
1325 (possibly cv-qualified) object to the (possibly cv-qualified) same
1326 object type (or a reference to it), to a (possibly cv-qualified) base
1327 class of that type (or a reference to it).... */
1328 else if (CLASS_TYPE_P (from) && !related_p
1329 && !(flags & LOOKUP_NO_CONVERSION))
1333 If the initializer expression
1335 -- has a class type (i.e., T2 is a class type) can be
1336 implicitly converted to an lvalue of type "cv3 T3," where
1337 "cv1 T1" is reference-compatible with "cv3 T3". (this
1338 conversion is selected by enumerating the applicable
1339 conversion functions (_over.match.ref_) and choosing the
1340 best one through overload resolution. (_over.match_).
1342 the reference is bound to the lvalue result of the conversion
1343 in the second case. */
1344 conv = convert_class_to_reference (rto, from, expr, flags);
1349 /* From this point on, we conceptually need temporaries, even if we
1350 elide them. Only the cases above are "direct bindings". */
1351 if (flags & LOOKUP_NO_TEMP_BIND)
1356 When a parameter of reference type is not bound directly to an
1357 argument expression, the conversion sequence is the one required
1358 to convert the argument expression to the underlying type of the
1359 reference according to _over.best.ics_. Conceptually, this
1360 conversion sequence corresponds to copy-initializing a temporary
1361 of the underlying type with the argument expression. Any
1362 difference in top-level cv-qualification is subsumed by the
1363 initialization itself and does not constitute a conversion. */
1367 Otherwise, the reference shall be to a non-volatile const type.
1369 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1370 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1375 Otherwise, a temporary of type "cv1 T1" is created and
1376 initialized from the initializer expression using the rules for a
1377 non-reference copy initialization. If T1 is reference-related to
1378 T2, cv1 must be the same cv-qualification as, or greater
1379 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1380 if (related_p && !at_least_as_qualified_p (to, from))
1383 /* We're generating a temporary now, but don't bind any more in the
1384 conversion (specifically, don't slice the temporary returned by a
1385 conversion operator). */
1386 flags |= LOOKUP_NO_TEMP_BIND;
1388 /* Temporaries are copy-initialized, except for this hack to allow
1389 explicit conversion ops to the copy ctor. See also
1390 add_function_candidate. */
1391 if (!(flags & LOOKUP_COPY_PARM))
1392 flags |= LOOKUP_ONLYCONVERTING;
1395 conv = implicit_conversion (to, from, expr, c_cast_p,
1400 conv = build_conv (ck_ref_bind, rto, conv);
1401 /* This reference binding, unlike those above, requires the
1402 creation of a temporary. */
1403 conv->need_temporary_p = true;
1404 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1409 /* Returns the implicit conversion sequence (see [over.ics]) from type
1410 FROM to type TO. The optional expression EXPR may affect the
1411 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1412 true, this conversion is coming from a C-style cast. */
1415 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1420 if (from == error_mark_node || to == error_mark_node
1421 || expr == error_mark_node)
1424 if (TREE_CODE (to) == REFERENCE_TYPE)
1425 conv = reference_binding (to, from, expr, c_cast_p, flags);
1427 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1432 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1434 if (is_std_init_list (to))
1435 return build_list_conv (to, expr, flags);
1437 /* Allow conversion from an initializer-list with one element to a
1439 if (SCALAR_TYPE_P (to))
1441 int nelts = CONSTRUCTOR_NELTS (expr);
1445 elt = integer_zero_node;
1446 else if (nelts == 1)
1447 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1449 elt = error_mark_node;
1451 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1455 conv->check_narrowing = true;
1456 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1457 /* Too many levels of braces, i.e. '{{1}}'. */
1464 if (expr != NULL_TREE
1465 && (MAYBE_CLASS_TYPE_P (from)
1466 || MAYBE_CLASS_TYPE_P (to))
1467 && (flags & LOOKUP_NO_CONVERSION) == 0)
1469 struct z_candidate *cand;
1470 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING));
1472 if (CLASS_TYPE_P (to)
1473 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1474 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1475 return build_aggr_conv (to, expr, flags);
1477 cand = build_user_type_conversion_1 (to, expr, convflags);
1479 conv = cand->second_conv;
1481 /* We used to try to bind a reference to a temporary here, but that
1482 is now handled after the recursive call to this function at the end
1483 of reference_binding. */
1490 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1491 functions. ARGS will not be changed until a single candidate is
1494 static struct z_candidate *
1495 add_candidate (struct z_candidate **candidates,
1496 tree fn, tree first_arg, const VEC(tree,gc) *args,
1497 size_t num_convs, conversion **convs,
1498 tree access_path, tree conversion_path,
1501 struct z_candidate *cand = (struct z_candidate *)
1502 conversion_obstack_alloc (sizeof (struct z_candidate));
1505 cand->first_arg = first_arg;
1507 cand->convs = convs;
1508 cand->num_convs = num_convs;
1509 cand->access_path = access_path;
1510 cand->conversion_path = conversion_path;
1511 cand->viable = viable;
1512 cand->next = *candidates;
1518 /* Create an overload candidate for the function or method FN called
1519 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1520 FLAGS is passed on to implicit_conversion.
1522 This does not change ARGS.
1524 CTYPE, if non-NULL, is the type we want to pretend this function
1525 comes from for purposes of overload resolution. */
1527 static struct z_candidate *
1528 add_function_candidate (struct z_candidate **candidates,
1529 tree fn, tree ctype, tree first_arg,
1530 const VEC(tree,gc) *args, tree access_path,
1531 tree conversion_path, int flags)
1533 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1537 tree orig_first_arg = first_arg;
1541 /* At this point we should not see any functions which haven't been
1542 explicitly declared, except for friend functions which will have
1543 been found using argument dependent lookup. */
1544 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1546 /* The `this', `in_chrg' and VTT arguments to constructors are not
1547 considered in overload resolution. */
1548 if (DECL_CONSTRUCTOR_P (fn))
1550 parmlist = skip_artificial_parms_for (fn, parmlist);
1551 skip = num_artificial_parms_for (fn);
1552 if (skip > 0 && first_arg != NULL_TREE)
1555 first_arg = NULL_TREE;
1561 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1562 convs = alloc_conversions (len);
1564 /* 13.3.2 - Viable functions [over.match.viable]
1565 First, to be a viable function, a candidate function shall have enough
1566 parameters to agree in number with the arguments in the list.
1568 We need to check this first; otherwise, checking the ICSes might cause
1569 us to produce an ill-formed template instantiation. */
1571 parmnode = parmlist;
1572 for (i = 0; i < len; ++i)
1574 if (parmnode == NULL_TREE || parmnode == void_list_node)
1576 parmnode = TREE_CHAIN (parmnode);
1579 if (i < len && parmnode)
1582 /* Make sure there are default args for the rest of the parms. */
1583 else if (!sufficient_parms_p (parmnode))
1589 /* Second, for F to be a viable function, there shall exist for each
1590 argument an implicit conversion sequence that converts that argument
1591 to the corresponding parameter of F. */
1593 parmnode = parmlist;
1595 for (i = 0; i < len; ++i)
1601 if (parmnode == void_list_node)
1604 if (i == 0 && first_arg != NULL_TREE)
1607 arg = VEC_index (tree, args,
1608 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1609 argtype = lvalue_type (arg);
1611 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1612 && ! DECL_CONSTRUCTOR_P (fn));
1616 tree parmtype = TREE_VALUE (parmnode);
1619 /* The type of the implicit object parameter ('this') for
1620 overload resolution is not always the same as for the
1621 function itself; conversion functions are considered to
1622 be members of the class being converted, and functions
1623 introduced by a using-declaration are considered to be
1624 members of the class that uses them.
1626 Since build_over_call ignores the ICS for the `this'
1627 parameter, we can just change the parm type. */
1628 if (ctype && is_this)
1631 = build_qualified_type (ctype,
1632 TYPE_QUALS (TREE_TYPE (parmtype)));
1633 parmtype = build_pointer_type (parmtype);
1636 if (ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn)
1639 /* Hack: Direct-initialize copy parm (i.e. suppress
1640 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1641 work. See also reference_binding. */
1642 lflags |= LOOKUP_COPY_PARM;
1643 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1644 lflags |= LOOKUP_NO_CONVERSION;
1647 lflags |= LOOKUP_ONLYCONVERTING;
1649 t = implicit_conversion (parmtype, argtype, arg,
1650 /*c_cast_p=*/false, lflags);
1654 t = build_identity_conv (argtype, arg);
1655 t->ellipsis_p = true;
1672 parmnode = TREE_CHAIN (parmnode);
1676 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1677 access_path, conversion_path, viable);
1680 /* Create an overload candidate for the conversion function FN which will
1681 be invoked for expression OBJ, producing a pointer-to-function which
1682 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1683 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1684 passed on to implicit_conversion.
1686 Actually, we don't really care about FN; we care about the type it
1687 converts to. There may be multiple conversion functions that will
1688 convert to that type, and we rely on build_user_type_conversion_1 to
1689 choose the best one; so when we create our candidate, we record the type
1690 instead of the function. */
1692 static struct z_candidate *
1693 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1694 tree first_arg, const VEC(tree,gc) *arglist,
1695 tree access_path, tree conversion_path)
1697 tree totype = TREE_TYPE (TREE_TYPE (fn));
1698 int i, len, viable, flags;
1699 tree parmlist, parmnode;
1702 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1703 parmlist = TREE_TYPE (parmlist);
1704 parmlist = TYPE_ARG_TYPES (parmlist);
1706 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1707 convs = alloc_conversions (len);
1708 parmnode = parmlist;
1710 flags = LOOKUP_IMPLICIT;
1712 /* Don't bother looking up the same type twice. */
1713 if (*candidates && (*candidates)->fn == totype)
1716 for (i = 0; i < len; ++i)
1723 else if (i == 1 && first_arg != NULL_TREE)
1726 arg = VEC_index (tree, arglist,
1727 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1728 argtype = lvalue_type (arg);
1731 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1733 else if (parmnode == void_list_node)
1736 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1737 /*c_cast_p=*/false, flags);
1740 t = build_identity_conv (argtype, arg);
1741 t->ellipsis_p = true;
1755 parmnode = TREE_CHAIN (parmnode);
1761 if (!sufficient_parms_p (parmnode))
1764 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1765 access_path, conversion_path, viable);
1769 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1770 tree type1, tree type2, tree *args, tree *argtypes,
1782 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1783 convs = alloc_conversions (num_convs);
1785 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
1786 conversion ops are allowed. We handle that here by just checking for
1787 boolean_type_node because other operators don't ask for it. COND_EXPR
1788 also does contextual conversion to bool for the first operand, but we
1789 handle that in build_conditional_expr, and type1 here is operand 2. */
1790 if (type1 != boolean_type_node)
1791 flags |= LOOKUP_ONLYCONVERTING;
1793 for (i = 0; i < 2; ++i)
1798 t = implicit_conversion (types[i], argtypes[i], args[i],
1799 /*c_cast_p=*/false, flags);
1803 /* We need something for printing the candidate. */
1804 t = build_identity_conv (types[i], NULL_TREE);
1811 /* For COND_EXPR we rearranged the arguments; undo that now. */
1814 convs[2] = convs[1];
1815 convs[1] = convs[0];
1816 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1817 /*c_cast_p=*/false, flags);
1824 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1826 /*access_path=*/NULL_TREE,
1827 /*conversion_path=*/NULL_TREE,
1832 is_complete (tree t)
1834 return COMPLETE_TYPE_P (complete_type (t));
1837 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1840 promoted_arithmetic_type_p (tree type)
1844 In this section, the term promoted integral type is used to refer
1845 to those integral types which are preserved by integral promotion
1846 (including e.g. int and long but excluding e.g. char).
1847 Similarly, the term promoted arithmetic type refers to promoted
1848 integral types plus floating types. */
1849 return ((CP_INTEGRAL_TYPE_P (type)
1850 && same_type_p (type_promotes_to (type), type))
1851 || TREE_CODE (type) == REAL_TYPE);
1854 /* Create any builtin operator overload candidates for the operator in
1855 question given the converted operand types TYPE1 and TYPE2. The other
1856 args are passed through from add_builtin_candidates to
1857 build_builtin_candidate.
1859 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1860 If CODE is requires candidates operands of the same type of the kind
1861 of which TYPE1 and TYPE2 are, we add both candidates
1862 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1865 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1866 enum tree_code code2, tree fnname, tree type1,
1867 tree type2, tree *args, tree *argtypes, int flags)
1871 case POSTINCREMENT_EXPR:
1872 case POSTDECREMENT_EXPR:
1873 args[1] = integer_zero_node;
1874 type2 = integer_type_node;
1883 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1884 and VQ is either volatile or empty, there exist candidate operator
1885 functions of the form
1886 VQ T& operator++(VQ T&);
1887 T operator++(VQ T&, int);
1888 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1889 type other than bool, and VQ is either volatile or empty, there exist
1890 candidate operator functions of the form
1891 VQ T& operator--(VQ T&);
1892 T operator--(VQ T&, int);
1893 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1894 complete object type, and VQ is either volatile or empty, there exist
1895 candidate operator functions of the form
1896 T*VQ& operator++(T*VQ&);
1897 T*VQ& operator--(T*VQ&);
1898 T* operator++(T*VQ&, int);
1899 T* operator--(T*VQ&, int); */
1901 case POSTDECREMENT_EXPR:
1902 case PREDECREMENT_EXPR:
1903 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1905 case POSTINCREMENT_EXPR:
1906 case PREINCREMENT_EXPR:
1907 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1909 type1 = build_reference_type (type1);
1914 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1915 exist candidate operator functions of the form
1919 8 For every function type T, there exist candidate operator functions of
1921 T& operator*(T*); */
1924 if (TREE_CODE (type1) == POINTER_TYPE
1925 && (TYPE_PTROB_P (type1)
1926 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1930 /* 9 For every type T, there exist candidate operator functions of the form
1933 10For every promoted arithmetic type T, there exist candidate operator
1934 functions of the form
1938 case UNARY_PLUS_EXPR: /* unary + */
1939 if (TREE_CODE (type1) == POINTER_TYPE)
1942 if (ARITHMETIC_TYPE_P (type1))
1946 /* 11For every promoted integral type T, there exist candidate operator
1947 functions of the form
1951 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1955 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1956 is the same type as C2 or is a derived class of C2, T is a complete
1957 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1958 there exist candidate operator functions of the form
1959 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1960 where CV12 is the union of CV1 and CV2. */
1963 if (TREE_CODE (type1) == POINTER_TYPE
1964 && TYPE_PTR_TO_MEMBER_P (type2))
1966 tree c1 = TREE_TYPE (type1);
1967 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1969 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1970 && (TYPE_PTRMEMFUNC_P (type2)
1971 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1976 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1977 didate operator functions of the form
1982 bool operator<(L, R);
1983 bool operator>(L, R);
1984 bool operator<=(L, R);
1985 bool operator>=(L, R);
1986 bool operator==(L, R);
1987 bool operator!=(L, R);
1988 where LR is the result of the usual arithmetic conversions between
1991 14For every pair of types T and I, where T is a cv-qualified or cv-
1992 unqualified complete object type and I is a promoted integral type,
1993 there exist candidate operator functions of the form
1994 T* operator+(T*, I);
1995 T& operator[](T*, I);
1996 T* operator-(T*, I);
1997 T* operator+(I, T*);
1998 T& operator[](I, T*);
2000 15For every T, where T is a pointer to complete object type, there exist
2001 candidate operator functions of the form112)
2002 ptrdiff_t operator-(T, T);
2004 16For every pointer or enumeration type T, there exist candidate operator
2005 functions of the form
2006 bool operator<(T, T);
2007 bool operator>(T, T);
2008 bool operator<=(T, T);
2009 bool operator>=(T, T);
2010 bool operator==(T, T);
2011 bool operator!=(T, T);
2013 17For every pointer to member type T, there exist candidate operator
2014 functions of the form
2015 bool operator==(T, T);
2016 bool operator!=(T, T); */
2019 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2021 if (TYPE_PTROB_P (type1)
2022 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2024 type2 = ptrdiff_type_node;
2028 case TRUNC_DIV_EXPR:
2029 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2035 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2036 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2038 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2043 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2055 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2057 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2059 if (TREE_CODE (type1) == ENUMERAL_TYPE
2060 && TREE_CODE (type2) == ENUMERAL_TYPE)
2062 if (TYPE_PTR_P (type1)
2063 && null_ptr_cst_p (args[1])
2064 && !uses_template_parms (type1))
2069 if (null_ptr_cst_p (args[0])
2070 && TYPE_PTR_P (type2)
2071 && !uses_template_parms (type2))
2079 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2082 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2084 type1 = ptrdiff_type_node;
2087 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2089 type2 = ptrdiff_type_node;
2094 /* 18For every pair of promoted integral types L and R, there exist candi-
2095 date operator functions of the form
2102 where LR is the result of the usual arithmetic conversions between
2105 case TRUNC_MOD_EXPR:
2111 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2115 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2116 type, VQ is either volatile or empty, and R is a promoted arithmetic
2117 type, there exist candidate operator functions of the form
2118 VQ L& operator=(VQ L&, R);
2119 VQ L& operator*=(VQ L&, R);
2120 VQ L& operator/=(VQ L&, R);
2121 VQ L& operator+=(VQ L&, R);
2122 VQ L& operator-=(VQ L&, R);
2124 20For every pair T, VQ), where T is any type and VQ is either volatile
2125 or empty, there exist candidate operator functions of the form
2126 T*VQ& operator=(T*VQ&, T*);
2128 21For every pair T, VQ), where T is a pointer to member type and VQ is
2129 either volatile or empty, there exist candidate operator functions of
2131 VQ T& operator=(VQ T&, T);
2133 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2134 unqualified complete object type, VQ is either volatile or empty, and
2135 I is a promoted integral type, there exist candidate operator func-
2137 T*VQ& operator+=(T*VQ&, I);
2138 T*VQ& operator-=(T*VQ&, I);
2140 23For every triple L, VQ, R), where L is an integral or enumeration
2141 type, VQ is either volatile or empty, and R is a promoted integral
2142 type, there exist candidate operator functions of the form
2144 VQ L& operator%=(VQ L&, R);
2145 VQ L& operator<<=(VQ L&, R);
2146 VQ L& operator>>=(VQ L&, R);
2147 VQ L& operator&=(VQ L&, R);
2148 VQ L& operator^=(VQ L&, R);
2149 VQ L& operator|=(VQ L&, R); */
2156 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2158 type2 = ptrdiff_type_node;
2162 case TRUNC_DIV_EXPR:
2163 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2167 case TRUNC_MOD_EXPR:
2173 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2178 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2180 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2181 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2182 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2183 || ((TYPE_PTRMEMFUNC_P (type1)
2184 || TREE_CODE (type1) == POINTER_TYPE)
2185 && null_ptr_cst_p (args[1])))
2195 type1 = build_reference_type (type1);
2201 For every pair of promoted arithmetic types L and R, there
2202 exist candidate operator functions of the form
2204 LR operator?(bool, L, R);
2206 where LR is the result of the usual arithmetic conversions
2207 between types L and R.
2209 For every type T, where T is a pointer or pointer-to-member
2210 type, there exist candidate operator functions of the form T
2211 operator?(bool, T, T); */
2213 if (promoted_arithmetic_type_p (type1)
2214 && promoted_arithmetic_type_p (type2))
2218 /* Otherwise, the types should be pointers. */
2219 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2220 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2223 /* We don't check that the two types are the same; the logic
2224 below will actually create two candidates; one in which both
2225 parameter types are TYPE1, and one in which both parameter
2233 /* If we're dealing with two pointer types or two enumeral types,
2234 we need candidates for both of them. */
2235 if (type2 && !same_type_p (type1, type2)
2236 && TREE_CODE (type1) == TREE_CODE (type2)
2237 && (TREE_CODE (type1) == REFERENCE_TYPE
2238 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2239 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2240 || TYPE_PTRMEMFUNC_P (type1)
2241 || MAYBE_CLASS_TYPE_P (type1)
2242 || TREE_CODE (type1) == ENUMERAL_TYPE))
2244 build_builtin_candidate
2245 (candidates, fnname, type1, type1, args, argtypes, flags);
2246 build_builtin_candidate
2247 (candidates, fnname, type2, type2, args, argtypes, flags);
2251 build_builtin_candidate
2252 (candidates, fnname, type1, type2, args, argtypes, flags);
2256 type_decays_to (tree type)
2258 if (TREE_CODE (type) == ARRAY_TYPE)
2259 return build_pointer_type (TREE_TYPE (type));
2260 if (TREE_CODE (type) == FUNCTION_TYPE)
2261 return build_pointer_type (type);
2265 /* There are three conditions of builtin candidates:
2267 1) bool-taking candidates. These are the same regardless of the input.
2268 2) pointer-pair taking candidates. These are generated for each type
2269 one of the input types converts to.
2270 3) arithmetic candidates. According to the standard, we should generate
2271 all of these, but I'm trying not to...
2273 Here we generate a superset of the possible candidates for this particular
2274 case. That is a subset of the full set the standard defines, plus some
2275 other cases which the standard disallows. add_builtin_candidate will
2276 filter out the invalid set. */
2279 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2280 enum tree_code code2, tree fnname, tree *args,
2285 tree type, argtypes[3];
2286 /* TYPES[i] is the set of possible builtin-operator parameter types
2287 we will consider for the Ith argument. These are represented as
2288 a TREE_LIST; the TREE_VALUE of each node is the potential
2292 for (i = 0; i < 3; ++i)
2295 argtypes[i] = unlowered_expr_type (args[i]);
2297 argtypes[i] = NULL_TREE;
2302 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2303 and VQ is either volatile or empty, there exist candidate operator
2304 functions of the form
2305 VQ T& operator++(VQ T&); */
2307 case POSTINCREMENT_EXPR:
2308 case PREINCREMENT_EXPR:
2309 case POSTDECREMENT_EXPR:
2310 case PREDECREMENT_EXPR:
2315 /* 24There also exist candidate operator functions of the form
2316 bool operator!(bool);
2317 bool operator&&(bool, bool);
2318 bool operator||(bool, bool); */
2320 case TRUTH_NOT_EXPR:
2321 build_builtin_candidate
2322 (candidates, fnname, boolean_type_node,
2323 NULL_TREE, args, argtypes, flags);
2326 case TRUTH_ORIF_EXPR:
2327 case TRUTH_ANDIF_EXPR:
2328 build_builtin_candidate
2329 (candidates, fnname, boolean_type_node,
2330 boolean_type_node, args, argtypes, flags);
2352 types[0] = types[1] = NULL_TREE;
2354 for (i = 0; i < 2; ++i)
2358 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2362 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2365 convs = lookup_conversions (argtypes[i]);
2367 if (code == COND_EXPR)
2369 if (real_lvalue_p (args[i]))
2370 types[i] = tree_cons
2371 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2373 types[i] = tree_cons
2374 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2380 for (; convs; convs = TREE_CHAIN (convs))
2382 type = TREE_TYPE (convs);
2385 && (TREE_CODE (type) != REFERENCE_TYPE
2386 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2389 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2390 types[i] = tree_cons (NULL_TREE, type, types[i]);
2392 type = non_reference (type);
2393 if (i != 0 || ! ref1)
2395 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2396 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2397 types[i] = tree_cons (NULL_TREE, type, types[i]);
2398 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2399 type = type_promotes_to (type);
2402 if (! value_member (type, types[i]))
2403 types[i] = tree_cons (NULL_TREE, type, types[i]);
2408 if (code == COND_EXPR && real_lvalue_p (args[i]))
2409 types[i] = tree_cons
2410 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2411 type = non_reference (argtypes[i]);
2412 if (i != 0 || ! ref1)
2414 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2415 if (enum_p && UNSCOPED_ENUM_P (type))
2416 types[i] = tree_cons (NULL_TREE, type, types[i]);
2417 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2418 type = type_promotes_to (type);
2420 types[i] = tree_cons (NULL_TREE, type, types[i]);
2424 /* Run through the possible parameter types of both arguments,
2425 creating candidates with those parameter types. */
2426 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2429 for (type = types[1]; type; type = TREE_CHAIN (type))
2430 add_builtin_candidate
2431 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2432 TREE_VALUE (type), args, argtypes, flags);
2434 add_builtin_candidate
2435 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2436 NULL_TREE, args, argtypes, flags);
2441 /* If TMPL can be successfully instantiated as indicated by
2442 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2444 TMPL is the template. EXPLICIT_TARGS are any explicit template
2445 arguments. ARGLIST is the arguments provided at the call-site.
2446 This does not change ARGLIST. The RETURN_TYPE is the desired type
2447 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2448 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2449 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2451 static struct z_candidate*
2452 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2453 tree ctype, tree explicit_targs, tree first_arg,
2454 const VEC(tree,gc) *arglist, tree return_type,
2455 tree access_path, tree conversion_path,
2456 int flags, tree obj, unification_kind_t strict)
2458 int ntparms = DECL_NTPARMS (tmpl);
2459 tree targs = make_tree_vec (ntparms);
2460 unsigned int len = VEC_length (tree, arglist);
2461 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2462 unsigned int skip_without_in_chrg = 0;
2463 tree first_arg_without_in_chrg = first_arg;
2464 tree *args_without_in_chrg;
2465 unsigned int nargs_without_in_chrg;
2466 unsigned int ia, ix;
2468 struct z_candidate *cand;
2472 /* We don't do deduction on the in-charge parameter, the VTT
2473 parameter or 'this'. */
2474 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2476 if (first_arg_without_in_chrg != NULL_TREE)
2477 first_arg_without_in_chrg = NULL_TREE;
2479 ++skip_without_in_chrg;
2482 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2483 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2484 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2486 if (first_arg_without_in_chrg != NULL_TREE)
2487 first_arg_without_in_chrg = NULL_TREE;
2489 ++skip_without_in_chrg;
2492 if (len < skip_without_in_chrg)
2495 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2496 + (len - skip_without_in_chrg));
2497 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2499 if (first_arg_without_in_chrg != NULL_TREE)
2501 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2504 for (ix = skip_without_in_chrg;
2505 VEC_iterate (tree, arglist, ix, arg);
2508 args_without_in_chrg[ia] = arg;
2511 gcc_assert (ia == nargs_without_in_chrg);
2513 i = fn_type_unification (tmpl, explicit_targs, targs,
2514 args_without_in_chrg,
2515 nargs_without_in_chrg,
2516 return_type, strict, flags);
2521 fn = instantiate_template (tmpl, targs, tf_none);
2522 if (fn == error_mark_node)
2527 A member function template is never instantiated to perform the
2528 copy of a class object to an object of its class type.
2530 It's a little unclear what this means; the standard explicitly
2531 does allow a template to be used to copy a class. For example,
2536 template <class T> A(const T&);
2539 void g () { A a (f ()); }
2541 the member template will be used to make the copy. The section
2542 quoted above appears in the paragraph that forbids constructors
2543 whose only parameter is (a possibly cv-qualified variant of) the
2544 class type, and a logical interpretation is that the intent was
2545 to forbid the instantiation of member templates which would then
2547 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2549 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2550 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2555 if (obj != NULL_TREE)
2556 /* Aha, this is a conversion function. */
2557 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2558 access_path, conversion_path);
2560 cand = add_function_candidate (candidates, fn, ctype,
2561 first_arg, arglist, access_path,
2562 conversion_path, flags);
2563 if (DECL_TI_TEMPLATE (fn) != tmpl)
2564 /* This situation can occur if a member template of a template
2565 class is specialized. Then, instantiate_template might return
2566 an instantiation of the specialization, in which case the
2567 DECL_TI_TEMPLATE field will point at the original
2568 specialization. For example:
2570 template <class T> struct S { template <class U> void f(U);
2571 template <> void f(int) {}; };
2575 Here, TMPL will be template <class U> S<double>::f(U).
2576 And, instantiate template will give us the specialization
2577 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2578 for this will point at template <class T> template <> S<T>::f(int),
2579 so that we can find the definition. For the purposes of
2580 overload resolution, however, we want the original TMPL. */
2581 cand->template_decl = build_template_info (tmpl, targs);
2583 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2589 static struct z_candidate *
2590 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2591 tree explicit_targs, tree first_arg,
2592 const VEC(tree,gc) *arglist, tree return_type,
2593 tree access_path, tree conversion_path, int flags,
2594 unification_kind_t strict)
2597 add_template_candidate_real (candidates, tmpl, ctype,
2598 explicit_targs, first_arg, arglist,
2599 return_type, access_path, conversion_path,
2600 flags, NULL_TREE, strict);
2604 static struct z_candidate *
2605 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2606 tree obj, tree first_arg,
2607 const VEC(tree,gc) *arglist,
2608 tree return_type, tree access_path,
2609 tree conversion_path)
2612 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2613 first_arg, arglist, return_type, access_path,
2614 conversion_path, 0, obj, DEDUCE_CONV);
2617 /* The CANDS are the set of candidates that were considered for
2618 overload resolution. Return the set of viable candidates. If none
2619 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2620 is true if a candidate should be considered viable only if it is
2623 static struct z_candidate*
2624 splice_viable (struct z_candidate *cands,
2628 struct z_candidate *viable;
2629 struct z_candidate **last_viable;
2630 struct z_candidate **cand;
2633 last_viable = &viable;
2634 *any_viable_p = false;
2639 struct z_candidate *c = *cand;
2640 if (strict_p ? c->viable == 1 : c->viable)
2645 last_viable = &c->next;
2646 *any_viable_p = true;
2652 return viable ? viable : cands;
2656 any_strictly_viable (struct z_candidate *cands)
2658 for (; cands; cands = cands->next)
2659 if (cands->viable == 1)
2664 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2665 words, it is about to become the "this" pointer for a member
2666 function call. Take the address of the object. */
2669 build_this (tree obj)
2671 /* In a template, we are only concerned about the type of the
2672 expression, so we can take a shortcut. */
2673 if (processing_template_decl)
2674 return build_address (obj);
2676 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2679 /* Returns true iff functions are equivalent. Equivalent functions are
2680 not '==' only if one is a function-local extern function or if
2681 both are extern "C". */
2684 equal_functions (tree fn1, tree fn2)
2686 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2687 || DECL_EXTERN_C_FUNCTION_P (fn1))
2688 return decls_match (fn1, fn2);
2692 /* Print information about one overload candidate CANDIDATE. MSGSTR
2693 is the text to print before the candidate itself.
2695 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2696 to have been run through gettext by the caller. This wart makes
2697 life simpler in print_z_candidates and for the translators. */
2700 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2702 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2704 if (candidate->num_convs == 3)
2705 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2706 candidate->convs[0]->type,
2707 candidate->convs[1]->type,
2708 candidate->convs[2]->type);
2709 else if (candidate->num_convs == 2)
2710 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2711 candidate->convs[0]->type,
2712 candidate->convs[1]->type);
2714 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2715 candidate->convs[0]->type);
2717 else if (TYPE_P (candidate->fn))
2718 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2719 else if (candidate->viable == -1)
2720 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2721 else if (DECL_DELETED_FN (candidate->fn))
2722 inform (input_location, "%s %+#D <deleted>", msgstr, candidate->fn);
2724 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2728 print_z_candidates (struct z_candidate *candidates)
2731 struct z_candidate *cand1;
2732 struct z_candidate **cand2;
2738 /* Remove deleted candidates. */
2740 for (cand2 = &cand1; *cand2; )
2742 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2743 && DECL_DELETED_FN ((*cand2)->fn))
2744 *cand2 = (*cand2)->next;
2746 cand2 = &(*cand2)->next;
2748 /* ...if there are any non-deleted ones. */
2752 /* There may be duplicates in the set of candidates. We put off
2753 checking this condition as long as possible, since we have no way
2754 to eliminate duplicates from a set of functions in less than n^2
2755 time. Now we are about to emit an error message, so it is more
2756 permissible to go slowly. */
2757 for (cand1 = candidates; cand1; cand1 = cand1->next)
2759 tree fn = cand1->fn;
2760 /* Skip builtin candidates and conversion functions. */
2761 if (TREE_CODE (fn) != FUNCTION_DECL)
2763 cand2 = &cand1->next;
2766 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2767 && equal_functions (fn, (*cand2)->fn))
2768 *cand2 = (*cand2)->next;
2770 cand2 = &(*cand2)->next;
2774 str = candidates->next ? _("candidates are:") : _("candidate is:");
2776 for (; candidates; candidates = candidates->next)
2778 print_z_candidate (spaces ? spaces : str, candidates);
2779 spaces = spaces ? spaces : get_spaces (str);
2784 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2785 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2786 the result of the conversion function to convert it to the final
2787 desired type. Merge the two sequences into a single sequence,
2788 and return the merged sequence. */
2791 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2795 gcc_assert (user_seq->kind == ck_user);
2797 /* Find the end of the second conversion sequence. */
2799 while ((*t)->kind != ck_identity)
2800 t = &((*t)->u.next);
2802 /* Replace the identity conversion with the user conversion
2806 /* The entire sequence is a user-conversion sequence. */
2807 std_seq->user_conv_p = true;
2812 /* Returns the best overload candidate to perform the requested
2813 conversion. This function is used for three the overloading situations
2814 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2815 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2816 per [dcl.init.ref], so we ignore temporary bindings. */
2818 static struct z_candidate *
2819 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2821 struct z_candidate *candidates, *cand;
2822 tree fromtype = TREE_TYPE (expr);
2823 tree ctors = NULL_TREE;
2824 tree conv_fns = NULL_TREE;
2825 conversion *conv = NULL;
2826 tree first_arg = NULL_TREE;
2827 VEC(tree,gc) *args = NULL;
2831 /* We represent conversion within a hierarchy using RVALUE_CONV and
2832 BASE_CONV, as specified by [over.best.ics]; these become plain
2833 constructor calls, as specified in [dcl.init]. */
2834 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2835 || !DERIVED_FROM_P (totype, fromtype));
2837 if (MAYBE_CLASS_TYPE_P (totype))
2838 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2840 if (MAYBE_CLASS_TYPE_P (fromtype))
2842 tree to_nonref = non_reference (totype);
2843 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2844 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2845 && DERIVED_FROM_P (to_nonref, fromtype)))
2847 /* [class.conv.fct] A conversion function is never used to
2848 convert a (possibly cv-qualified) object to the (possibly
2849 cv-qualified) same object type (or a reference to it), to a
2850 (possibly cv-qualified) base class of that type (or a
2851 reference to it)... */
2854 conv_fns = lookup_conversions (fromtype);
2858 flags |= LOOKUP_NO_CONVERSION;
2860 /* It's OK to bind a temporary for converting constructor arguments, but
2861 not in converting the return value of a conversion operator. */
2862 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2863 flags &= ~LOOKUP_NO_TEMP_BIND;
2867 ctors = BASELINK_FUNCTIONS (ctors);
2869 first_arg = build_int_cst (build_pointer_type (totype), 0);
2870 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2871 && !TYPE_HAS_LIST_CTOR (totype))
2873 args = ctor_to_vec (expr);
2874 /* We still allow more conversions within an init-list. */
2875 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2876 /* But not for the copy ctor. */
2877 |LOOKUP_NO_COPY_CTOR_CONVERSION
2878 |LOOKUP_NO_NARROWING);
2881 args = make_tree_vector_single (expr);
2883 /* We should never try to call the abstract or base constructor
2885 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2886 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2888 for (; ctors; ctors = OVL_NEXT (ctors))
2890 tree ctor = OVL_CURRENT (ctors);
2891 if (DECL_NONCONVERTING_P (ctor)
2892 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2895 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2896 cand = add_template_candidate (&candidates, ctor, totype,
2897 NULL_TREE, first_arg, args, NULL_TREE,
2898 TYPE_BINFO (totype),
2899 TYPE_BINFO (totype),
2903 cand = add_function_candidate (&candidates, ctor, totype,
2904 first_arg, args, TYPE_BINFO (totype),
2905 TYPE_BINFO (totype),
2910 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2912 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2913 set, then this is copy-initialization. In that case, "The
2914 result of the call is then used to direct-initialize the
2915 object that is the destination of the copy-initialization."
2918 We represent this in the conversion sequence with an
2919 rvalue conversion, which means a constructor call. */
2920 if (TREE_CODE (totype) != REFERENCE_TYPE
2921 && !(convflags & LOOKUP_NO_TEMP_BIND))
2923 = build_conv (ck_rvalue, totype, cand->second_conv);
2928 first_arg = build_this (expr);
2930 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2933 tree conversion_path = TREE_PURPOSE (conv_fns);
2935 /* If we are called to convert to a reference type, we are trying to
2936 find an lvalue binding, so don't even consider temporaries. If
2937 we don't find an lvalue binding, the caller will try again to
2938 look for a temporary binding. */
2939 if (TREE_CODE (totype) == REFERENCE_TYPE)
2940 convflags |= LOOKUP_NO_TEMP_BIND;
2942 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2944 tree fn = OVL_CURRENT (fns);
2945 tree first = first_arg;
2947 if (DECL_NONCONVERTING_P (fn)
2948 && (flags & LOOKUP_ONLYCONVERTING))
2951 /* Lambdas have a static conversion op. */
2952 if (DECL_STATIC_FUNCTION_P (fn))
2955 /* [over.match.funcs] For conversion functions, the function
2956 is considered to be a member of the class of the implicit
2957 object argument for the purpose of defining the type of
2958 the implicit object parameter.
2960 So we pass fromtype as CTYPE to add_*_candidate. */
2962 if (TREE_CODE (fn) == TEMPLATE_DECL)
2963 cand = add_template_candidate (&candidates, fn, fromtype,
2965 first, NULL, totype,
2966 TYPE_BINFO (fromtype),
2971 cand = add_function_candidate (&candidates, fn, fromtype,
2973 TYPE_BINFO (fromtype),
2980 = implicit_conversion (totype,
2981 TREE_TYPE (TREE_TYPE (cand->fn)),
2983 /*c_cast_p=*/false, convflags);
2985 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2986 copy-initialization. In that case, "The result of the
2987 call is then used to direct-initialize the object that is
2988 the destination of the copy-initialization." [dcl.init]
2990 We represent this in the conversion sequence with an
2991 rvalue conversion, which means a constructor call. But
2992 don't add a second rvalue conversion if there's already
2993 one there. Which there really shouldn't be, but it's
2994 harmless since we'd add it here anyway. */
2995 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2996 && !(convflags & LOOKUP_NO_TEMP_BIND))
2997 ics = build_conv (ck_rvalue, totype, ics);
2999 cand->second_conv = ics;
3003 else if (candidates->viable == 1 && ics->bad_p)
3009 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3013 cand = tourney (candidates);
3016 if (flags & LOOKUP_COMPLAIN)
3018 error ("conversion from %qT to %qT is ambiguous",
3020 print_z_candidates (candidates);
3023 cand = candidates; /* any one will do */
3024 cand->second_conv = build_ambiguous_conv (totype, expr);
3025 cand->second_conv->user_conv_p = true;
3026 if (!any_strictly_viable (candidates))
3027 cand->second_conv->bad_p = true;
3028 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3029 ambiguous conversion is no worse than another user-defined
3035 /* Build the user conversion sequence. */
3038 (DECL_CONSTRUCTOR_P (cand->fn)
3039 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3040 build_identity_conv (TREE_TYPE (expr), expr));
3043 /* Remember that this was a list-initialization. */
3044 if (flags & LOOKUP_NO_NARROWING)
3045 conv->check_narrowing = true;
3047 /* Combine it with the second conversion sequence. */
3048 cand->second_conv = merge_conversion_sequences (conv,
3051 if (cand->viable == -1)
3052 cand->second_conv->bad_p = true;
3058 build_user_type_conversion (tree totype, tree expr, int flags)
3060 struct z_candidate *cand
3061 = build_user_type_conversion_1 (totype, expr, flags);
3065 if (cand->second_conv->kind == ck_ambig)
3066 return error_mark_node;
3067 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3068 return convert_from_reference (expr);
3073 /* Do any initial processing on the arguments to a function call. */
3075 static VEC(tree,gc) *
3076 resolve_args (VEC(tree,gc) *args)
3081 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3083 if (error_operand_p (arg))
3085 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3087 error ("invalid use of void expression");
3090 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3096 /* Perform overload resolution on FN, which is called with the ARGS.
3098 Return the candidate function selected by overload resolution, or
3099 NULL if the event that overload resolution failed. In the case
3100 that overload resolution fails, *CANDIDATES will be the set of
3101 candidates considered, and ANY_VIABLE_P will be set to true or
3102 false to indicate whether or not any of the candidates were
3105 The ARGS should already have gone through RESOLVE_ARGS before this
3106 function is called. */
3108 static struct z_candidate *
3109 perform_overload_resolution (tree fn,
3110 const VEC(tree,gc) *args,
3111 struct z_candidate **candidates,
3114 struct z_candidate *cand;
3115 tree explicit_targs = NULL_TREE;
3116 int template_only = 0;
3119 *any_viable_p = true;
3122 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3123 || TREE_CODE (fn) == TEMPLATE_DECL
3124 || TREE_CODE (fn) == OVERLOAD
3125 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3127 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3129 explicit_targs = TREE_OPERAND (fn, 1);
3130 fn = TREE_OPERAND (fn, 0);
3134 /* Add the various candidate functions. */
3135 add_candidates (fn, args, explicit_targs, template_only,
3136 /*conversion_path=*/NULL_TREE,
3137 /*access_path=*/NULL_TREE,
3141 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3145 cand = tourney (*candidates);
3149 /* Return an expression for a call to FN (a namespace-scope function,
3150 or a static member function) with the ARGS. This may change
3154 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3155 tsubst_flags_t complain)
3157 struct z_candidate *candidates, *cand;
3162 if (args != NULL && *args != NULL)
3164 *args = resolve_args (*args);
3166 return error_mark_node;
3169 /* If this function was found without using argument dependent
3170 lookup, then we want to ignore any undeclared friend
3176 fn = remove_hidden_names (fn);
3179 if (complain & tf_error)
3180 error ("no matching function for call to %<%D(%A)%>",
3181 DECL_NAME (OVL_CURRENT (orig_fn)),
3182 build_tree_list_vec (*args));
3183 return error_mark_node;
3187 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3188 p = conversion_obstack_alloc (0);
3190 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3194 if (complain & tf_error)
3196 if (!any_viable_p && candidates && ! candidates->next)
3197 return cp_build_function_call_vec (candidates->fn, args, complain);
3198 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3199 fn = TREE_OPERAND (fn, 0);
3201 error ("no matching function for call to %<%D(%A)%>",
3202 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3204 error ("call of overloaded %<%D(%A)%> is ambiguous",
3205 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3207 print_z_candidates (candidates);
3209 result = error_mark_node;
3212 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3214 /* Free all the conversions we allocated. */
3215 obstack_free (&conversion_obstack, p);
3220 /* Build a call to a global operator new. FNNAME is the name of the
3221 operator (either "operator new" or "operator new[]") and ARGS are
3222 the arguments provided. This may change ARGS. *SIZE points to the
3223 total number of bytes required by the allocation, and is updated if
3224 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3225 be used. If this function determines that no cookie should be
3226 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3227 non-NULL, it will be set, upon return, to the allocation function
3231 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3232 tree *size, tree *cookie_size,
3236 struct z_candidate *candidates;
3237 struct z_candidate *cand;
3242 VEC_safe_insert (tree, gc, *args, 0, *size);
3243 *args = resolve_args (*args);
3245 return error_mark_node;
3251 If this lookup fails to find the name, or if the allocated type
3252 is not a class type, the allocation function's name is looked
3253 up in the global scope.
3255 we disregard block-scope declarations of "operator new". */
3256 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3258 /* Figure out what function is being called. */
3259 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3261 /* If no suitable function could be found, issue an error message
3266 error ("no matching function for call to %<%D(%A)%>",
3267 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3269 error ("call of overloaded %<%D(%A)%> is ambiguous",
3270 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3272 print_z_candidates (candidates);
3273 return error_mark_node;
3276 /* If a cookie is required, add some extra space. Whether
3277 or not a cookie is required cannot be determined until
3278 after we know which function was called. */
3281 bool use_cookie = true;
3282 if (!abi_version_at_least (2))
3284 /* In G++ 3.2, the check was implemented incorrectly; it
3285 looked at the placement expression, rather than the
3286 type of the function. */
3287 if (VEC_length (tree, *args) == 2
3288 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3296 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3297 /* Skip the size_t parameter. */
3298 arg_types = TREE_CHAIN (arg_types);
3299 /* Check the remaining parameters (if any). */
3301 && TREE_CHAIN (arg_types) == void_list_node
3302 && same_type_p (TREE_VALUE (arg_types),
3306 /* If we need a cookie, adjust the number of bytes allocated. */
3309 /* Update the total size. */
3310 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3311 /* Update the argument list to reflect the adjusted size. */
3312 VEC_replace (tree, *args, 0, *size);
3315 *cookie_size = NULL_TREE;
3318 /* Tell our caller which function we decided to call. */
3322 /* Build the CALL_EXPR. */
3323 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3326 /* Build a new call to operator(). This may change ARGS. */
3329 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3331 struct z_candidate *candidates = 0, *cand;
3332 tree fns, convs, first_mem_arg = NULL_TREE;
3333 tree type = TREE_TYPE (obj);
3335 tree result = NULL_TREE;
3338 if (error_operand_p (obj))
3339 return error_mark_node;
3341 obj = prep_operand (obj);
3343 if (TYPE_PTRMEMFUNC_P (type))
3345 if (complain & tf_error)
3346 /* It's no good looking for an overloaded operator() on a
3347 pointer-to-member-function. */
3348 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3349 return error_mark_node;
3352 if (TYPE_BINFO (type))
3354 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3355 if (fns == error_mark_node)
3356 return error_mark_node;
3361 if (args != NULL && *args != NULL)
3363 *args = resolve_args (*args);
3365 return error_mark_node;
3368 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3369 p = conversion_obstack_alloc (0);
3373 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3374 first_mem_arg = build_this (obj);
3376 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3378 tree fn = OVL_CURRENT (fns);
3380 tree lfirst = first_mem_arg;
3381 if (DECL_STATIC_FUNCTION_P (fn))
3384 if (TREE_CODE (fn) == TEMPLATE_DECL)
3385 add_template_candidate (&candidates, fn, base, NULL_TREE,
3386 lfirst, *args, NULL_TREE,
3389 LOOKUP_NORMAL, DEDUCE_CALL);
3391 add_function_candidate
3392 (&candidates, fn, base, lfirst, *args, TYPE_BINFO (type),
3393 TYPE_BINFO (type), LOOKUP_NORMAL);
3397 /* Rather than mess with handling static conversion ops here, just don't
3398 look at conversions in lambdas. */
3399 if (LAMBDA_TYPE_P (type))
3402 convs = lookup_conversions (type);
3404 for (; convs; convs = TREE_CHAIN (convs))
3406 tree fns = TREE_VALUE (convs);
3407 tree totype = TREE_TYPE (convs);
3409 if ((TREE_CODE (totype) == POINTER_TYPE
3410 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3411 || (TREE_CODE (totype) == REFERENCE_TYPE
3412 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3413 || (TREE_CODE (totype) == REFERENCE_TYPE
3414 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3415 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3416 for (; fns; fns = OVL_NEXT (fns))
3418 tree fn = OVL_CURRENT (fns);
3420 if (DECL_NONCONVERTING_P (fn))
3423 if (TREE_CODE (fn) == TEMPLATE_DECL)
3424 add_template_conv_candidate
3425 (&candidates, fn, obj, NULL_TREE, *args, totype,
3426 /*access_path=*/NULL_TREE,
3427 /*conversion_path=*/NULL_TREE);
3429 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3430 *args, /*conversion_path=*/NULL_TREE,
3431 /*access_path=*/NULL_TREE);
3435 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3438 if (complain & tf_error)
3440 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3441 build_tree_list_vec (*args));
3442 print_z_candidates (candidates);
3444 result = error_mark_node;
3448 cand = tourney (candidates);
3451 if (complain & tf_error)
3453 error ("call of %<(%T) (%A)%> is ambiguous",
3454 TREE_TYPE (obj), build_tree_list_vec (*args));
3455 print_z_candidates (candidates);
3457 result = error_mark_node;
3459 /* Since cand->fn will be a type, not a function, for a conversion
3460 function, we must be careful not to unconditionally look at
3462 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3463 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3464 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3467 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3469 obj = convert_from_reference (obj);
3470 result = cp_build_function_call_vec (obj, args, complain);
3474 /* Free all the conversions we allocated. */
3475 obstack_free (&conversion_obstack, p);
3481 op_error (enum tree_code code, enum tree_code code2,
3482 tree arg1, tree arg2, tree arg3, bool match)
3486 if (code == MODIFY_EXPR)
3487 opname = assignment_operator_name_info[code2].name;
3489 opname = operator_name_info[code].name;
3495 error ("ambiguous overload for ternary %<operator?:%> "
3496 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3498 error ("no match for ternary %<operator?:%> "
3499 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3502 case POSTINCREMENT_EXPR:
3503 case POSTDECREMENT_EXPR:
3505 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
3506 opname, arg1, opname);
3508 error ("no match for %<operator%s%> in %<%E%s%>",
3509 opname, arg1, opname);
3514 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
3517 error ("no match for %<operator[]%> in %<%E[%E]%>",
3524 error ("ambiguous overload for %qs in %<%s %E%>",
3525 opname, opname, arg1);
3527 error ("no match for %qs in %<%s %E%>",
3528 opname, opname, arg1);
3534 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
3535 opname, arg1, opname, arg2);
3537 error ("no match for %<operator%s%> in %<%E %s %E%>",
3538 opname, arg1, opname, arg2);
3541 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
3542 opname, opname, arg1);
3544 error ("no match for %<operator%s%> in %<%s%E%>",
3545 opname, opname, arg1);
3550 /* Return the implicit conversion sequence that could be used to
3551 convert E1 to E2 in [expr.cond]. */
3554 conditional_conversion (tree e1, tree e2)
3556 tree t1 = non_reference (TREE_TYPE (e1));
3557 tree t2 = non_reference (TREE_TYPE (e2));
3563 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3564 implicitly converted (clause _conv_) to the type "reference to
3565 T2", subject to the constraint that in the conversion the
3566 reference must bind directly (_dcl.init.ref_) to E1. */
3567 if (real_lvalue_p (e2))
3569 conv = implicit_conversion (build_reference_type (t2),
3573 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3580 If E1 and E2 have class type, and the underlying class types are
3581 the same or one is a base class of the other: E1 can be converted
3582 to match E2 if the class of T2 is the same type as, or a base
3583 class of, the class of T1, and the cv-qualification of T2 is the
3584 same cv-qualification as, or a greater cv-qualification than, the
3585 cv-qualification of T1. If the conversion is applied, E1 is
3586 changed to an rvalue of type T2 that still refers to the original
3587 source class object (or the appropriate subobject thereof). */
3588 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3589 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3591 if (good_base && at_least_as_qualified_p (t2, t1))
3593 conv = build_identity_conv (t1, e1);
3594 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3595 TYPE_MAIN_VARIANT (t2)))
3596 conv = build_conv (ck_base, t2, conv);
3598 conv = build_conv (ck_rvalue, t2, conv);
3607 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3608 converted to the type that expression E2 would have if E2 were
3609 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3610 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3614 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3615 arguments to the conditional expression. */
3618 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3619 tsubst_flags_t complain)
3623 tree result = NULL_TREE;
3625 tree result_type = NULL_TREE;
3626 bool lvalue_p = true;
3627 struct z_candidate *candidates = 0;
3628 struct z_candidate *cand;
3631 /* As a G++ extension, the second argument to the conditional can be
3632 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3633 c'.) If the second operand is omitted, make sure it is
3634 calculated only once. */
3637 if (complain & tf_error)
3638 pedwarn (input_location, OPT_pedantic,
3639 "ISO C++ forbids omitting the middle term of a ?: expression");
3641 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3642 if (real_lvalue_p (arg1))
3643 arg2 = arg1 = stabilize_reference (arg1);
3645 arg2 = arg1 = save_expr (arg1);
3650 The first expression is implicitly converted to bool (clause
3652 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
3655 /* If something has already gone wrong, just pass that fact up the
3657 if (error_operand_p (arg1)
3658 || error_operand_p (arg2)
3659 || error_operand_p (arg3))
3660 return error_mark_node;
3664 If either the second or the third operand has type (possibly
3665 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3666 array-to-pointer (_conv.array_), and function-to-pointer
3667 (_conv.func_) standard conversions are performed on the second
3668 and third operands. */
3669 arg2_type = unlowered_expr_type (arg2);
3670 arg3_type = unlowered_expr_type (arg3);
3671 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3673 /* Do the conversions. We don't these for `void' type arguments
3674 since it can't have any effect and since decay_conversion
3675 does not handle that case gracefully. */
3676 if (!VOID_TYPE_P (arg2_type))
3677 arg2 = decay_conversion (arg2);
3678 if (!VOID_TYPE_P (arg3_type))
3679 arg3 = decay_conversion (arg3);
3680 arg2_type = TREE_TYPE (arg2);
3681 arg3_type = TREE_TYPE (arg3);
3685 One of the following shall hold:
3687 --The second or the third operand (but not both) is a
3688 throw-expression (_except.throw_); the result is of the
3689 type of the other and is an rvalue.
3691 --Both the second and the third operands have type void; the
3692 result is of type void and is an rvalue.
3694 We must avoid calling force_rvalue for expressions of type
3695 "void" because it will complain that their value is being
3697 if (TREE_CODE (arg2) == THROW_EXPR
3698 && TREE_CODE (arg3) != THROW_EXPR)
3700 if (!VOID_TYPE_P (arg3_type))
3701 arg3 = force_rvalue (arg3);
3702 arg3_type = TREE_TYPE (arg3);
3703 result_type = arg3_type;
3705 else if (TREE_CODE (arg2) != THROW_EXPR
3706 && TREE_CODE (arg3) == THROW_EXPR)
3708 if (!VOID_TYPE_P (arg2_type))
3709 arg2 = force_rvalue (arg2);
3710 arg2_type = TREE_TYPE (arg2);
3711 result_type = arg2_type;
3713 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3714 result_type = void_type_node;
3717 if (complain & tf_error)
3719 if (VOID_TYPE_P (arg2_type))
3720 error ("second operand to the conditional operator "
3721 "is of type %<void%>, "
3722 "but the third operand is neither a throw-expression "
3723 "nor of type %<void%>");
3725 error ("third operand to the conditional operator "
3726 "is of type %<void%>, "
3727 "but the second operand is neither a throw-expression "
3728 "nor of type %<void%>");
3730 return error_mark_node;
3734 goto valid_operands;
3738 Otherwise, if the second and third operand have different types,
3739 and either has (possibly cv-qualified) class type, an attempt is
3740 made to convert each of those operands to the type of the other. */
3741 else if (!same_type_p (arg2_type, arg3_type)
3742 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3747 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3748 p = conversion_obstack_alloc (0);
3750 conv2 = conditional_conversion (arg2, arg3);
3751 conv3 = conditional_conversion (arg3, arg2);
3755 If both can be converted, or one can be converted but the
3756 conversion is ambiguous, the program is ill-formed. If
3757 neither can be converted, the operands are left unchanged and
3758 further checking is performed as described below. If exactly
3759 one conversion is possible, that conversion is applied to the
3760 chosen operand and the converted operand is used in place of
3761 the original operand for the remainder of this section. */
3762 if ((conv2 && !conv2->bad_p
3763 && conv3 && !conv3->bad_p)
3764 || (conv2 && conv2->kind == ck_ambig)
3765 || (conv3 && conv3->kind == ck_ambig))
3767 error ("operands to ?: have different types %qT and %qT",
3768 arg2_type, arg3_type);
3769 result = error_mark_node;
3771 else if (conv2 && (!conv2->bad_p || !conv3))
3773 arg2 = convert_like (conv2, arg2, complain);
3774 arg2 = convert_from_reference (arg2);
3775 arg2_type = TREE_TYPE (arg2);
3776 /* Even if CONV2 is a valid conversion, the result of the
3777 conversion may be invalid. For example, if ARG3 has type
3778 "volatile X", and X does not have a copy constructor
3779 accepting a "volatile X&", then even if ARG2 can be
3780 converted to X, the conversion will fail. */
3781 if (error_operand_p (arg2))
3782 result = error_mark_node;
3784 else if (conv3 && (!conv3->bad_p || !conv2))
3786 arg3 = convert_like (conv3, arg3, complain);
3787 arg3 = convert_from_reference (arg3);
3788 arg3_type = TREE_TYPE (arg3);
3789 if (error_operand_p (arg3))
3790 result = error_mark_node;
3793 /* Free all the conversions we allocated. */
3794 obstack_free (&conversion_obstack, p);
3799 /* If, after the conversion, both operands have class type,
3800 treat the cv-qualification of both operands as if it were the
3801 union of the cv-qualification of the operands.
3803 The standard is not clear about what to do in this
3804 circumstance. For example, if the first operand has type
3805 "const X" and the second operand has a user-defined
3806 conversion to "volatile X", what is the type of the second
3807 operand after this step? Making it be "const X" (matching
3808 the first operand) seems wrong, as that discards the
3809 qualification without actually performing a copy. Leaving it
3810 as "volatile X" seems wrong as that will result in the
3811 conditional expression failing altogether, even though,
3812 according to this step, the one operand could be converted to
3813 the type of the other. */
3814 if ((conv2 || conv3)
3815 && CLASS_TYPE_P (arg2_type)
3816 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3817 arg2_type = arg3_type =
3818 cp_build_qualified_type (arg2_type,
3819 TYPE_QUALS (arg2_type)
3820 | TYPE_QUALS (arg3_type));
3825 If the second and third operands are lvalues and have the same
3826 type, the result is of that type and is an lvalue. */
3827 if (real_lvalue_p (arg2)
3828 && real_lvalue_p (arg3)
3829 && same_type_p (arg2_type, arg3_type))
3831 result_type = arg2_type;
3832 goto valid_operands;
3837 Otherwise, the result is an rvalue. If the second and third
3838 operand do not have the same type, and either has (possibly
3839 cv-qualified) class type, overload resolution is used to
3840 determine the conversions (if any) to be applied to the operands
3841 (_over.match.oper_, _over.built_). */
3843 if (!same_type_p (arg2_type, arg3_type)
3844 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3850 /* Rearrange the arguments so that add_builtin_candidate only has
3851 to know about two args. In build_builtin_candidate, the
3852 arguments are unscrambled. */
3856 add_builtin_candidates (&candidates,
3859 ansi_opname (COND_EXPR),
3865 If the overload resolution fails, the program is
3867 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3870 if (complain & tf_error)
3872 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3873 print_z_candidates (candidates);
3875 return error_mark_node;
3877 cand = tourney (candidates);
3880 if (complain & tf_error)
3882 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3883 print_z_candidates (candidates);
3885 return error_mark_node;
3890 Otherwise, the conversions thus determined are applied, and
3891 the converted operands are used in place of the original
3892 operands for the remainder of this section. */
3893 conv = cand->convs[0];
3894 arg1 = convert_like (conv, arg1, complain);
3895 conv = cand->convs[1];
3896 arg2 = convert_like (conv, arg2, complain);
3897 arg2_type = TREE_TYPE (arg2);
3898 conv = cand->convs[2];
3899 arg3 = convert_like (conv, arg3, complain);
3900 arg3_type = TREE_TYPE (arg3);
3905 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3906 and function-to-pointer (_conv.func_) standard conversions are
3907 performed on the second and third operands.
3909 We need to force the lvalue-to-rvalue conversion here for class types,
3910 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3911 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3914 arg2 = force_rvalue (arg2);
3915 if (!CLASS_TYPE_P (arg2_type))
3916 arg2_type = TREE_TYPE (arg2);
3918 arg3 = force_rvalue (arg3);
3919 if (!CLASS_TYPE_P (arg3_type))
3920 arg3_type = TREE_TYPE (arg3);
3922 if (arg2 == error_mark_node || arg3 == error_mark_node)
3923 return error_mark_node;
3927 After those conversions, one of the following shall hold:
3929 --The second and third operands have the same type; the result is of
3931 if (same_type_p (arg2_type, arg3_type))
3932 result_type = arg2_type;
3935 --The second and third operands have arithmetic or enumeration
3936 type; the usual arithmetic conversions are performed to bring
3937 them to a common type, and the result is of that type. */
3938 else if ((ARITHMETIC_TYPE_P (arg2_type)
3939 || UNSCOPED_ENUM_P (arg2_type))
3940 && (ARITHMETIC_TYPE_P (arg3_type)
3941 || UNSCOPED_ENUM_P (arg3_type)))
3943 /* In this case, there is always a common type. */
3944 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3947 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3948 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3950 if (complain & tf_warning)
3952 "enumeral mismatch in conditional expression: %qT vs %qT",
3953 arg2_type, arg3_type);
3955 else if (extra_warnings
3956 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3957 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3958 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3959 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3961 if (complain & tf_warning)
3963 "enumeral and non-enumeral type in conditional expression");
3966 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3967 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3971 --The second and third operands have pointer type, or one has
3972 pointer type and the other is a null pointer constant; pointer
3973 conversions (_conv.ptr_) and qualification conversions
3974 (_conv.qual_) are performed to bring them to their composite
3975 pointer type (_expr.rel_). The result is of the composite
3978 --The second and third operands have pointer to member type, or
3979 one has pointer to member type and the other is a null pointer
3980 constant; pointer to member conversions (_conv.mem_) and
3981 qualification conversions (_conv.qual_) are performed to bring
3982 them to a common type, whose cv-qualification shall match the
3983 cv-qualification of either the second or the third operand.
3984 The result is of the common type. */
3985 else if ((null_ptr_cst_p (arg2)
3986 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3987 || (null_ptr_cst_p (arg3)
3988 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3989 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3990 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3991 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3993 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3994 arg3, CPO_CONDITIONAL_EXPR,
3996 if (result_type == error_mark_node)
3997 return error_mark_node;
3998 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3999 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4004 if (complain & tf_error)
4005 error ("operands to ?: have different types %qT and %qT",
4006 arg2_type, arg3_type);
4007 return error_mark_node;
4011 result_save = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4012 result = fold_if_not_in_template (result_save);
4014 if (cp_unevaluated_operand && TREE_CODE (result) == CALL_EXPR)
4015 /* Avoid folding to a CALL_EXPR within decltype (c++/42013). */
4016 result = result_save;
4018 /* We can't use result_type below, as fold might have returned a
4023 /* Expand both sides into the same slot, hopefully the target of
4024 the ?: expression. We used to check for TARGET_EXPRs here,
4025 but now we sometimes wrap them in NOP_EXPRs so the test would
4027 if (CLASS_TYPE_P (TREE_TYPE (result)))
4028 result = get_target_expr (result);
4029 /* If this expression is an rvalue, but might be mistaken for an
4030 lvalue, we must add a NON_LVALUE_EXPR. */
4031 result = rvalue (result);
4037 /* OPERAND is an operand to an expression. Perform necessary steps
4038 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4042 prep_operand (tree operand)
4046 if (CLASS_TYPE_P (TREE_TYPE (operand))
4047 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4048 /* Make sure the template type is instantiated now. */
4049 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4055 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4056 OVERLOAD) to the CANDIDATES, returning an updated list of
4057 CANDIDATES. The ARGS are the arguments provided to the call,
4058 without any implicit object parameter. This may change ARGS. The
4059 EXPLICIT_TARGS are explicit template arguments provided.
4060 TEMPLATE_ONLY is true if only template functions should be
4061 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4062 add_function_candidate. */
4065 add_candidates (tree fns, const VEC(tree,gc) *args,
4066 tree explicit_targs, bool template_only,
4067 tree conversion_path, tree access_path,
4069 struct z_candidate **candidates)
4072 VEC(tree,gc) *non_static_args;
4075 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4076 /* Delay creating the implicit this parameter until it is needed. */
4077 non_static_args = NULL;
4078 first_arg = NULL_TREE;
4084 const VEC(tree,gc) *fn_args;
4086 fn = OVL_CURRENT (fns);
4087 /* Figure out which set of arguments to use. */
4088 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4090 /* If this function is a non-static member, prepend the implicit
4091 object parameter. */
4092 if (non_static_args == NULL)
4097 non_static_args = VEC_alloc (tree, gc,
4098 VEC_length (tree, args) - 1);
4099 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4100 VEC_quick_push (tree, non_static_args, arg);
4102 if (first_arg == NULL_TREE)
4103 first_arg = build_this (VEC_index (tree, args, 0));
4104 fn_first_arg = first_arg;
4105 fn_args = non_static_args;
4109 /* Otherwise, just use the list of arguments provided. */
4110 fn_first_arg = NULL_TREE;
4114 if (TREE_CODE (fn) == TEMPLATE_DECL)
4115 add_template_candidate (candidates,
4126 else if (!template_only)
4127 add_function_candidate (candidates,
4135 fns = OVL_NEXT (fns);
4139 /* Even unsigned enum types promote to signed int. We don't want to
4140 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4141 original argument and ARG is the argument after any conversions
4142 have been applied. We set TREE_NO_WARNING if we have added a cast
4143 from an unsigned enum type to a signed integer type. */
4146 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4148 if (orig_arg != NULL_TREE
4151 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4152 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4153 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4154 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4155 TREE_NO_WARNING (arg) = 1;
4159 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4160 bool *overloaded_p, tsubst_flags_t complain)
4162 tree orig_arg1 = arg1;
4163 tree orig_arg2 = arg2;
4164 tree orig_arg3 = arg3;
4165 struct z_candidate *candidates = 0, *cand;
4166 VEC(tree,gc) *arglist;
4169 tree result = NULL_TREE;
4170 bool result_valid_p = false;
4171 enum tree_code code2 = NOP_EXPR;
4172 enum tree_code code_orig_arg1 = ERROR_MARK;
4173 enum tree_code code_orig_arg2 = ERROR_MARK;
4179 if (error_operand_p (arg1)
4180 || error_operand_p (arg2)
4181 || error_operand_p (arg3))
4182 return error_mark_node;
4184 if (code == MODIFY_EXPR)
4186 code2 = TREE_CODE (arg3);
4188 fnname = ansi_assopname (code2);
4191 fnname = ansi_opname (code);
4193 arg1 = prep_operand (arg1);
4199 case VEC_DELETE_EXPR:
4201 /* Use build_op_new_call and build_op_delete_call instead. */
4205 /* Use build_op_call instead. */
4208 case TRUTH_ORIF_EXPR:
4209 case TRUTH_ANDIF_EXPR:
4210 case TRUTH_AND_EXPR:
4212 /* These are saved for the sake of warn_logical_operator. */
4213 code_orig_arg1 = TREE_CODE (arg1);
4214 code_orig_arg2 = TREE_CODE (arg2);
4220 arg2 = prep_operand (arg2);
4221 arg3 = prep_operand (arg3);
4223 if (code == COND_EXPR)
4224 /* Use build_conditional_expr instead. */
4226 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4227 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4230 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4231 arg2 = integer_zero_node;
4233 arglist = VEC_alloc (tree, gc, 3);
4234 VEC_quick_push (tree, arglist, arg1);
4235 if (arg2 != NULL_TREE)
4236 VEC_quick_push (tree, arglist, arg2);
4237 if (arg3 != NULL_TREE)
4238 VEC_quick_push (tree, arglist, arg3);
4240 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4241 p = conversion_obstack_alloc (0);
4243 /* Add namespace-scope operators to the list of functions to
4245 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4246 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4247 flags, &candidates);
4248 /* Add class-member operators to the candidate set. */
4249 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4253 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4254 if (fns == error_mark_node)
4256 result = error_mark_node;
4257 goto user_defined_result_ready;
4260 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4262 BASELINK_BINFO (fns),
4263 TYPE_BINFO (TREE_TYPE (arg1)),
4264 flags, &candidates);
4269 args[2] = NULL_TREE;
4271 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4277 /* For these, the built-in candidates set is empty
4278 [over.match.oper]/3. We don't want non-strict matches
4279 because exact matches are always possible with built-in
4280 operators. The built-in candidate set for COMPONENT_REF
4281 would be empty too, but since there are no such built-in
4282 operators, we accept non-strict matches for them. */
4287 strict_p = pedantic;
4291 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4296 case POSTINCREMENT_EXPR:
4297 case POSTDECREMENT_EXPR:
4298 /* Don't try anything fancy if we're not allowed to produce
4300 if (!(complain & tf_error))
4301 return error_mark_node;
4303 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4304 distinguish between prefix and postfix ++ and
4305 operator++() was used for both, so we allow this with
4307 if (flags & LOOKUP_COMPLAIN)
4309 const char *msg = (flag_permissive)
4310 ? G_("no %<%D(int)%> declared for postfix %qs,"
4311 " trying prefix operator instead")
4312 : G_("no %<%D(int)%> declared for postfix %qs");
4313 permerror (input_location, msg, fnname,
4314 operator_name_info[code].name);
4317 if (!flag_permissive)
4318 return error_mark_node;
4320 if (code == POSTINCREMENT_EXPR)
4321 code = PREINCREMENT_EXPR;
4323 code = PREDECREMENT_EXPR;
4324 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4325 overloaded_p, complain);
4328 /* The caller will deal with these. */
4333 result_valid_p = true;
4337 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4339 /* If one of the arguments of the operator represents
4340 an invalid use of member function pointer, try to report
4341 a meaningful error ... */
4342 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4343 || invalid_nonstatic_memfn_p (arg2, tf_error)
4344 || invalid_nonstatic_memfn_p (arg3, tf_error))
4345 /* We displayed the error message. */;
4348 /* ... Otherwise, report the more generic
4349 "no matching operator found" error */
4350 op_error (code, code2, arg1, arg2, arg3, FALSE);
4351 print_z_candidates (candidates);
4354 result = error_mark_node;
4360 cand = tourney (candidates);
4363 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4365 op_error (code, code2, arg1, arg2, arg3, TRUE);
4366 print_z_candidates (candidates);
4368 result = error_mark_node;
4370 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4373 *overloaded_p = true;
4375 if (resolve_args (arglist) == NULL)
4376 result = error_mark_node;
4378 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4382 /* Give any warnings we noticed during overload resolution. */
4383 if (cand->warnings && (complain & tf_warning))
4385 struct candidate_warning *w;
4386 for (w = cand->warnings; w; w = w->next)
4387 joust (cand, w->loser, 1);
4390 /* Check for comparison of different enum types. */
4399 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4400 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4401 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4402 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4403 && (complain & tf_warning))
4405 warning (OPT_Wenum_compare,
4406 "comparison between %q#T and %q#T",
4407 TREE_TYPE (arg1), TREE_TYPE (arg2));
4414 /* We need to strip any leading REF_BIND so that bitfields
4415 don't cause errors. This should not remove any important
4416 conversions, because builtins don't apply to class
4417 objects directly. */
4418 conv = cand->convs[0];
4419 if (conv->kind == ck_ref_bind)
4420 conv = conv->u.next;
4421 arg1 = convert_like (conv, arg1, complain);
4425 /* We need to call warn_logical_operator before
4426 converting arg2 to a boolean_type. */
4427 if (complain & tf_warning)
4428 warn_logical_operator (input_location, code, boolean_type_node,
4429 code_orig_arg1, arg1,
4430 code_orig_arg2, arg2);
4432 conv = cand->convs[1];
4433 if (conv->kind == ck_ref_bind)
4434 conv = conv->u.next;
4435 arg2 = convert_like (conv, arg2, complain);
4439 conv = cand->convs[2];
4440 if (conv->kind == ck_ref_bind)
4441 conv = conv->u.next;
4442 arg3 = convert_like (conv, arg3, complain);
4448 user_defined_result_ready:
4450 /* Free all the conversions we allocated. */
4451 obstack_free (&conversion_obstack, p);
4453 if (result || result_valid_p)
4457 avoid_sign_compare_warnings (orig_arg1, arg1);
4458 avoid_sign_compare_warnings (orig_arg2, arg2);
4459 avoid_sign_compare_warnings (orig_arg3, arg3);
4464 return cp_build_modify_expr (arg1, code2, arg2, complain);
4467 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
4469 case TRUTH_ANDIF_EXPR:
4470 case TRUTH_ORIF_EXPR:
4471 case TRUTH_AND_EXPR:
4473 warn_logical_operator (input_location, code, boolean_type_node,
4474 code_orig_arg1, arg1, code_orig_arg2, arg2);
4479 case TRUNC_DIV_EXPR:
4490 case TRUNC_MOD_EXPR:
4494 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4496 case UNARY_PLUS_EXPR:
4499 case TRUTH_NOT_EXPR:
4500 case PREINCREMENT_EXPR:
4501 case POSTINCREMENT_EXPR:
4502 case PREDECREMENT_EXPR:
4503 case POSTDECREMENT_EXPR:
4506 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4509 return build_array_ref (input_location, arg1, arg2);
4512 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
4516 /* The caller will deal with these. */
4528 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
4529 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
4532 non_placement_deallocation_fn_p (tree t)
4534 /* A template instance is never a usual deallocation function,
4535 regardless of its signature. */
4536 if (TREE_CODE (t) == TEMPLATE_DECL
4537 || primary_template_instantiation_p (t))
4540 /* If a class T has a member deallocation function named operator delete
4541 with exactly one parameter, then that function is a usual
4542 (non-placement) deallocation function. If class T does not declare
4543 such an operator delete but does declare a member deallocation
4544 function named operator delete with exactly two parameters, the second
4545 of which has type std::size_t (18.2), then this function is a usual
4546 deallocation function. */
4547 t = FUNCTION_ARG_CHAIN (t);
4548 if (t == void_list_node
4549 || (t && same_type_p (TREE_VALUE (t), size_type_node)
4550 && TREE_CHAIN (t) == void_list_node))
4555 /* Build a call to operator delete. This has to be handled very specially,
4556 because the restrictions on what signatures match are different from all
4557 other call instances. For a normal delete, only a delete taking (void *)
4558 or (void *, size_t) is accepted. For a placement delete, only an exact
4559 match with the placement new is accepted.
4561 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4562 ADDR is the pointer to be deleted.
4563 SIZE is the size of the memory block to be deleted.
4564 GLOBAL_P is true if the delete-expression should not consider
4565 class-specific delete operators.
4566 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4568 If this call to "operator delete" is being generated as part to
4569 deallocate memory allocated via a new-expression (as per [expr.new]
4570 which requires that if the initialization throws an exception then
4571 we call a deallocation function), then ALLOC_FN is the allocation
4575 build_op_delete_call (enum tree_code code, tree addr, tree size,
4576 bool global_p, tree placement,
4579 tree fn = NULL_TREE;
4580 tree fns, fnname, type, t;
4582 if (addr == error_mark_node)
4583 return error_mark_node;
4585 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4587 fnname = ansi_opname (code);
4589 if (CLASS_TYPE_P (type)
4590 && COMPLETE_TYPE_P (complete_type (type))
4594 If the result of the lookup is ambiguous or inaccessible, or if
4595 the lookup selects a placement deallocation function, the
4596 program is ill-formed.
4598 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4600 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4601 if (fns == error_mark_node)
4602 return error_mark_node;
4607 if (fns == NULL_TREE)
4608 fns = lookup_name_nonclass (fnname);
4610 /* Strip const and volatile from addr. */
4611 addr = cp_convert (ptr_type_node, addr);
4615 /* "A declaration of a placement deallocation function matches the
4616 declaration of a placement allocation function if it has the same
4617 number of parameters and, after parameter transformations (8.3.5),
4618 all parameter types except the first are identical."
4620 So we build up the function type we want and ask instantiate_type
4621 to get it for us. */
4622 t = FUNCTION_ARG_CHAIN (alloc_fn);
4623 t = tree_cons (NULL_TREE, ptr_type_node, t);
4624 t = build_function_type (void_type_node, t);
4626 fn = instantiate_type (t, fns, tf_none);
4627 if (fn == error_mark_node)
4630 if (BASELINK_P (fn))
4631 fn = BASELINK_FUNCTIONS (fn);
4633 /* "If the lookup finds the two-parameter form of a usual deallocation
4634 function (3.7.4.2) and that function, considered as a placement
4635 deallocation function, would have been selected as a match for the
4636 allocation function, the program is ill-formed." */
4637 if (non_placement_deallocation_fn_p (fn))
4639 /* But if the class has an operator delete (void *), then that is
4640 the usual deallocation function, so we shouldn't complain
4641 about using the operator delete (void *, size_t). */
4642 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4643 t; t = OVL_NEXT (t))
4645 tree elt = OVL_CURRENT (t);
4646 if (non_placement_deallocation_fn_p (elt)
4647 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
4650 permerror (0, "non-placement deallocation function %q+D", fn);
4651 permerror (input_location, "selected for placement delete");
4656 /* "Any non-placement deallocation function matches a non-placement
4657 allocation function. If the lookup finds a single matching
4658 deallocation function, that function will be called; otherwise, no
4659 deallocation function will be called." */
4660 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4661 t; t = OVL_NEXT (t))
4663 tree elt = OVL_CURRENT (t);
4664 if (non_placement_deallocation_fn_p (elt))
4667 /* "If a class T has a member deallocation function named
4668 operator delete with exactly one parameter, then that
4669 function is a usual (non-placement) deallocation
4670 function. If class T does not declare such an operator
4671 delete but does declare a member deallocation function named
4672 operator delete with exactly two parameters, the second of
4673 which has type std::size_t (18.2), then this function is a
4674 usual deallocation function."
4676 So (void*) beats (void*, size_t). */
4677 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4682 /* If we have a matching function, call it. */
4685 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
4687 /* If the FN is a member function, make sure that it is
4689 if (BASELINK_P (fns))
4690 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
4692 /* Core issue 901: It's ok to new a type with deleted delete. */
4693 if (DECL_DELETED_FN (fn) && alloc_fn)
4698 /* The placement args might not be suitable for overload
4699 resolution at this point, so build the call directly. */
4700 int nargs = call_expr_nargs (placement);
4701 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4704 for (i = 1; i < nargs; i++)
4705 argarray[i] = CALL_EXPR_ARG (placement, i);
4707 return build_cxx_call (fn, nargs, argarray);
4712 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4713 VEC_quick_push (tree, args, addr);
4714 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
4715 VEC_quick_push (tree, args, size);
4716 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4717 VEC_free (tree, gc, args);
4724 If no unambiguous matching deallocation function can be found,
4725 propagating the exception does not cause the object's memory to
4730 warning (0, "no corresponding deallocation function for %qD",
4735 error ("no suitable %<operator %s%> for %qT",
4736 operator_name_info[(int)code].name, type);
4737 return error_mark_node;
4740 /* If the current scope isn't allowed to access DECL along
4741 BASETYPE_PATH, give an error. The most derived class in
4742 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4743 the declaration to use in the error diagnostic. */
4746 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4748 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4750 if (!accessible_p (basetype_path, decl, true))
4752 if (TREE_PRIVATE (decl))
4753 error ("%q+#D is private", diag_decl);
4754 else if (TREE_PROTECTED (decl))
4755 error ("%q+#D is protected", diag_decl);
4757 error ("%q+#D is inaccessible", diag_decl);
4758 error ("within this context");
4765 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4766 bitwise or of LOOKUP_* values. If any errors are warnings are
4767 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4768 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4772 build_temp (tree expr, tree type, int flags,
4773 diagnostic_t *diagnostic_kind)
4778 savew = warningcount, savee = errorcount;
4779 args = make_tree_vector_single (expr);
4780 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4781 &args, type, flags, tf_warning_or_error);
4782 release_tree_vector (args);
4783 if (warningcount > savew)
4784 *diagnostic_kind = DK_WARNING;
4785 else if (errorcount > savee)
4786 *diagnostic_kind = DK_ERROR;
4788 *diagnostic_kind = DK_UNSPECIFIED;
4792 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4793 EXPR is implicitly converted to type TOTYPE.
4794 FN and ARGNUM are used for diagnostics. */
4797 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4799 tree t = non_reference (totype);
4801 /* Issue warnings about peculiar, but valid, uses of NULL. */
4802 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4805 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4808 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4811 /* Issue warnings if "false" is converted to a NULL pointer */
4812 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4813 warning (OPT_Wconversion,
4814 "converting %<false%> to pointer type for argument %P of %qD",
4818 /* Perform the conversions in CONVS on the expression EXPR. FN and
4819 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4820 indicates the `this' argument of a method. INNER is nonzero when
4821 being called to continue a conversion chain. It is negative when a
4822 reference binding will be applied, positive otherwise. If
4823 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4824 conversions will be emitted if appropriate. If C_CAST_P is true,
4825 this conversion is coming from a C-style cast; in that case,
4826 conversions to inaccessible bases are permitted. */
4829 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4830 int inner, bool issue_conversion_warnings,
4831 bool c_cast_p, tsubst_flags_t complain)
4833 tree totype = convs->type;
4834 diagnostic_t diag_kind;
4838 && convs->kind != ck_user
4839 && convs->kind != ck_list
4840 && convs->kind != ck_ambig
4841 && convs->kind != ck_ref_bind
4842 && convs->kind != ck_rvalue
4843 && convs->kind != ck_base)
4845 conversion *t = convs;
4847 /* Give a helpful error if this is bad because of excess braces. */
4848 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4849 && SCALAR_TYPE_P (totype)
4850 && CONSTRUCTOR_NELTS (expr) > 0
4851 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4852 permerror (input_location, "too many braces around initializer for %qT", totype);
4854 for (; t; t = convs->u.next)
4856 if (t->kind == ck_user || !t->bad_p)
4858 expr = convert_like_real (t, expr, fn, argnum, 1,
4859 /*issue_conversion_warnings=*/false,
4864 else if (t->kind == ck_ambig)
4865 return convert_like_real (t, expr, fn, argnum, 1,
4866 /*issue_conversion_warnings=*/false,
4869 else if (t->kind == ck_identity)
4872 if (complain & tf_error)
4874 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4876 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4879 return error_mark_node;
4881 return cp_convert (totype, expr);
4884 if (issue_conversion_warnings && (complain & tf_warning))
4885 conversion_null_warnings (totype, expr, fn, argnum);
4887 switch (convs->kind)
4891 struct z_candidate *cand = convs->cand;
4892 tree convfn = cand->fn;
4895 /* When converting from an init list we consider explicit
4896 constructors, but actually trying to call one is an error. */
4897 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4899 if (complain & tf_error)
4900 error ("converting to %qT from initializer list would use "
4901 "explicit constructor %qD", totype, convfn);
4903 return error_mark_node;
4906 /* Set user_conv_p on the argument conversions, so rvalue/base
4907 handling knows not to allow any more UDCs. */
4908 for (i = 0; i < cand->num_convs; ++i)
4909 cand->convs[i]->user_conv_p = true;
4911 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4913 /* If this is a constructor or a function returning an aggr type,
4914 we need to build up a TARGET_EXPR. */
4915 if (DECL_CONSTRUCTOR_P (convfn))
4917 expr = build_cplus_new (totype, expr);
4919 /* Remember that this was list-initialization. */
4920 if (convs->check_narrowing)
4921 TARGET_EXPR_LIST_INIT_P (expr) = true;
4927 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4929 int nelts = CONSTRUCTOR_NELTS (expr);
4931 expr = integer_zero_node;
4932 else if (nelts == 1)
4933 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4938 if (type_unknown_p (expr))
4939 expr = instantiate_type (totype, expr, complain);
4940 /* Convert a constant to its underlying value, unless we are
4941 about to bind it to a reference, in which case we need to
4942 leave it as an lvalue. */
4945 expr = decl_constant_value (expr);
4946 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4947 /* If __null has been converted to an integer type, we do not
4948 want to warn about uses of EXPR as an integer, rather than
4950 expr = build_int_cst (totype, 0);
4954 /* Call build_user_type_conversion again for the error. */
4955 return build_user_type_conversion
4956 (totype, convs->u.expr, LOOKUP_NORMAL);
4960 /* Conversion to std::initializer_list<T>. */
4961 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4962 tree new_ctor = build_constructor (init_list_type_node, NULL);
4963 unsigned len = CONSTRUCTOR_NELTS (expr);
4965 VEC(tree,gc) *parms;
4968 /* Convert all the elements. */
4969 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4971 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4972 1, false, false, complain);
4973 if (sub == error_mark_node)
4975 check_narrowing (TREE_TYPE (sub), val);
4976 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4978 /* Build up the array. */
4979 elttype = cp_build_qualified_type
4980 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4981 array = build_array_of_n_type (elttype, len);
4982 array = finish_compound_literal (array, new_ctor);
4984 parms = make_tree_vector ();
4985 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4986 VEC_safe_push (tree, gc, parms, size_int (len));
4987 /* Call the private constructor. */
4988 push_deferring_access_checks (dk_no_check);
4989 new_ctor = build_special_member_call
4990 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4991 release_tree_vector (parms);
4992 pop_deferring_access_checks ();
4993 return build_cplus_new (totype, new_ctor);
4997 return get_target_expr (digest_init (totype, expr));
5003 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5004 convs->kind == ck_ref_bind ? -1 : 1,
5005 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5008 if (expr == error_mark_node)
5009 return error_mark_node;
5011 switch (convs->kind)
5014 expr = convert_bitfield_to_declared_type (expr);
5015 if (! MAYBE_CLASS_TYPE_P (totype))
5017 /* Else fall through. */
5019 if (convs->kind == ck_base && !convs->need_temporary_p)
5021 /* We are going to bind a reference directly to a base-class
5022 subobject of EXPR. */
5023 /* Build an expression for `*((base*) &expr)'. */
5024 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5025 expr = convert_to_base (expr, build_pointer_type (totype),
5026 !c_cast_p, /*nonnull=*/true);
5027 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5031 /* Copy-initialization where the cv-unqualified version of the source
5032 type is the same class as, or a derived class of, the class of the
5033 destination [is treated as direct-initialization]. [dcl.init] */
5034 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5035 if (convs->user_conv_p)
5036 /* This conversion is being done in the context of a user-defined
5037 conversion (i.e. the second step of copy-initialization), so
5038 don't allow any more. */
5039 flags |= LOOKUP_NO_CONVERSION;
5040 expr = build_temp (expr, totype, flags, &diag_kind);
5041 if (diag_kind && fn)
5043 if ((complain & tf_error))
5044 emit_diagnostic (diag_kind, input_location, 0,
5045 " initializing argument %P of %qD", argnum, fn);
5046 else if (diag_kind == DK_ERROR)
5047 return error_mark_node;
5049 return build_cplus_new (totype, expr);
5053 tree ref_type = totype;
5055 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5056 && real_lvalue_p (expr))
5058 if (complain & tf_error)
5060 error ("cannot bind %qT lvalue to %qT",
5061 TREE_TYPE (expr), totype);
5063 error (" initializing argument %P of %q+D", argnum, fn);
5065 return error_mark_node;
5068 /* If necessary, create a temporary.
5070 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5071 that need temporaries, even when their types are reference
5072 compatible with the type of reference being bound, so the
5073 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5075 if (convs->need_temporary_p
5076 || TREE_CODE (expr) == CONSTRUCTOR
5077 || TREE_CODE (expr) == VA_ARG_EXPR)
5079 tree type = convs->u.next->type;
5080 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5082 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
5083 && !TYPE_REF_IS_RVALUE (ref_type))
5085 if (complain & tf_error)
5087 /* If the reference is volatile or non-const, we
5088 cannot create a temporary. */
5089 if (lvalue & clk_bitfield)
5090 error ("cannot bind bitfield %qE to %qT",
5092 else if (lvalue & clk_packed)
5093 error ("cannot bind packed field %qE to %qT",
5096 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5098 return error_mark_node;
5100 /* If the source is a packed field, and we must use a copy
5101 constructor, then building the target expr will require
5102 binding the field to the reference parameter to the
5103 copy constructor, and we'll end up with an infinite
5104 loop. If we can use a bitwise copy, then we'll be
5106 if ((lvalue & clk_packed)
5107 && CLASS_TYPE_P (type)
5108 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
5110 if (complain & tf_error)
5111 error ("cannot bind packed field %qE to %qT",
5113 return error_mark_node;
5115 if (lvalue & clk_bitfield)
5117 expr = convert_bitfield_to_declared_type (expr);
5118 expr = fold_convert (type, expr);
5120 expr = build_target_expr_with_type (expr, type);
5123 /* Take the address of the thing to which we will bind the
5125 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5126 if (expr == error_mark_node)
5127 return error_mark_node;
5129 /* Convert it to a pointer to the type referred to by the
5130 reference. This will adjust the pointer if a derived to
5131 base conversion is being performed. */
5132 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5134 /* Convert the pointer to the desired reference type. */
5135 return build_nop (ref_type, expr);
5139 return decay_conversion (expr);
5142 /* Warn about deprecated conversion if appropriate. */
5143 string_conv_p (totype, expr, 1);
5148 expr = convert_to_base (expr, totype, !c_cast_p,
5150 return build_nop (totype, expr);
5153 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5160 if (convs->check_narrowing)
5161 check_narrowing (totype, expr);
5163 if (issue_conversion_warnings && (complain & tf_warning))
5164 expr = convert_and_check (totype, expr);
5166 expr = convert (totype, expr);
5171 /* ARG is being passed to a varargs function. Perform any conversions
5172 required. Return the converted value. */
5175 convert_arg_to_ellipsis (tree arg)
5179 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5180 standard conversions are performed. */
5181 arg = decay_conversion (arg);
5184 If the argument has integral or enumeration type that is subject
5185 to the integral promotions (_conv.prom_), or a floating point
5186 type that is subject to the floating point promotion
5187 (_conv.fpprom_), the value of the argument is converted to the
5188 promoted type before the call. */
5189 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5190 && (TYPE_PRECISION (TREE_TYPE (arg))
5191 < TYPE_PRECISION (double_type_node))
5192 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (arg))))
5193 arg = convert_to_real (double_type_node, arg);
5194 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5195 arg = perform_integral_promotions (arg);
5197 arg = require_complete_type (arg);
5199 if (arg != error_mark_node
5200 && (type_has_nontrivial_copy_init (TREE_TYPE (arg))
5201 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (arg))))
5203 /* [expr.call] 5.2.2/7:
5204 Passing a potentially-evaluated argument of class type (Clause 9)
5205 with a non-trivial copy constructor or a non-trivial destructor
5206 with no corresponding parameter is conditionally-supported, with
5207 implementation-defined semantics.
5209 We used to just warn here and do a bitwise copy, but now
5210 cp_expr_size will abort if we try to do that.
5212 If the call appears in the context of a sizeof expression,
5213 it is not potentially-evaluated. */
5214 if (cp_unevaluated_operand == 0)
5215 error ("cannot pass objects of non-trivially-copyable "
5216 "type %q#T through %<...%>", TREE_TYPE (arg));
5222 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5225 build_x_va_arg (tree expr, tree type)
5227 if (processing_template_decl)
5228 return build_min (VA_ARG_EXPR, type, expr);
5230 type = complete_type_or_else (type, NULL_TREE);
5232 if (expr == error_mark_node || !type)
5233 return error_mark_node;
5235 if (type_has_nontrivial_copy_init (type)
5236 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5237 || TREE_CODE (type) == REFERENCE_TYPE)
5239 /* Remove reference types so we don't ICE later on. */
5240 tree type1 = non_reference (type);
5241 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5242 error ("cannot receive objects of non-trivially-copyable type %q#T "
5243 "through %<...%>; ", type);
5244 expr = convert (build_pointer_type (type1), null_node);
5245 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
5249 return build_va_arg (input_location, expr, type);
5252 /* TYPE has been given to va_arg. Apply the default conversions which
5253 would have happened when passed via ellipsis. Return the promoted
5254 type, or the passed type if there is no change. */
5257 cxx_type_promotes_to (tree type)
5261 /* Perform the array-to-pointer and function-to-pointer
5263 type = type_decays_to (type);
5265 promote = type_promotes_to (type);
5266 if (same_type_p (type, promote))
5272 /* ARG is a default argument expression being passed to a parameter of
5273 the indicated TYPE, which is a parameter to FN. Do any required
5274 conversions. Return the converted value. */
5276 static GTY(()) VEC(tree,gc) *default_arg_context;
5279 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5284 /* If the ARG is an unparsed default argument expression, the
5285 conversion cannot be performed. */
5286 if (TREE_CODE (arg) == DEFAULT_ARG)
5288 error ("the default argument for parameter %d of %qD has "
5289 "not yet been parsed",
5291 return error_mark_node;
5294 /* Detect recursion. */
5295 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5298 error ("recursive evaluation of default argument for %q#D", fn);
5299 return error_mark_node;
5301 VEC_safe_push (tree, gc, default_arg_context, fn);
5303 if (fn && DECL_TEMPLATE_INFO (fn))
5304 arg = tsubst_default_argument (fn, type, arg);
5310 The names in the expression are bound, and the semantic
5311 constraints are checked, at the point where the default
5312 expressions appears.
5314 we must not perform access checks here. */
5315 push_deferring_access_checks (dk_no_check);
5316 arg = break_out_target_exprs (arg);
5317 if (TREE_CODE (arg) == CONSTRUCTOR)
5319 arg = digest_init (type, arg);
5320 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5321 "default argument", fn, parmnum,
5322 tf_warning_or_error);
5326 /* We must make a copy of ARG, in case subsequent processing
5327 alters any part of it. For example, during gimplification a
5328 cast of the form (T) &X::f (where "f" is a member function)
5329 will lead to replacing the PTRMEM_CST for &X::f with a
5330 VAR_DECL. We can avoid the copy for constants, since they
5331 are never modified in place. */
5332 if (!CONSTANT_CLASS_P (arg))
5333 arg = unshare_expr (arg);
5334 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5335 "default argument", fn, parmnum,
5336 tf_warning_or_error);
5337 arg = convert_for_arg_passing (type, arg);
5339 pop_deferring_access_checks();
5341 VEC_pop (tree, default_arg_context);
5346 /* Returns the type which will really be used for passing an argument of
5350 type_passed_as (tree type)
5352 /* Pass classes with copy ctors by invisible reference. */
5353 if (TREE_ADDRESSABLE (type))
5355 type = build_reference_type (type);
5356 /* There are no other pointers to this temporary. */
5357 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5359 else if (targetm.calls.promote_prototypes (type)
5360 && INTEGRAL_TYPE_P (type)
5361 && COMPLETE_TYPE_P (type)
5362 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5363 TYPE_SIZE (integer_type_node)))
5364 type = integer_type_node;
5369 /* Actually perform the appropriate conversion. */
5372 convert_for_arg_passing (tree type, tree val)
5376 /* If VAL is a bitfield, then -- since it has already been converted
5377 to TYPE -- it cannot have a precision greater than TYPE.
5379 If it has a smaller precision, we must widen it here. For
5380 example, passing "int f:3;" to a function expecting an "int" will
5381 not result in any conversion before this point.
5383 If the precision is the same we must not risk widening. For
5384 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5385 often have type "int", even though the C++ type for the field is
5386 "long long". If the value is being passed to a function
5387 expecting an "int", then no conversions will be required. But,
5388 if we call convert_bitfield_to_declared_type, the bitfield will
5389 be converted to "long long". */
5390 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5392 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5393 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5395 if (val == error_mark_node)
5397 /* Pass classes with copy ctors by invisible reference. */
5398 else if (TREE_ADDRESSABLE (type))
5399 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5400 else if (targetm.calls.promote_prototypes (type)
5401 && INTEGRAL_TYPE_P (type)
5402 && COMPLETE_TYPE_P (type)
5403 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5404 TYPE_SIZE (integer_type_node)))
5405 val = perform_integral_promotions (val);
5406 if (warn_missing_format_attribute)
5408 tree rhstype = TREE_TYPE (val);
5409 const enum tree_code coder = TREE_CODE (rhstype);
5410 const enum tree_code codel = TREE_CODE (type);
5411 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5413 && check_missing_format_attribute (type, rhstype))
5414 warning (OPT_Wmissing_format_attribute,
5415 "argument of function call might be a candidate for a format attribute");
5420 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5421 which no conversions at all should be done. This is true for some
5422 builtins which don't act like normal functions. */
5425 magic_varargs_p (tree fn)
5427 if (DECL_BUILT_IN (fn))
5428 switch (DECL_FUNCTION_CODE (fn))
5430 case BUILT_IN_CLASSIFY_TYPE:
5431 case BUILT_IN_CONSTANT_P:
5432 case BUILT_IN_NEXT_ARG:
5433 case BUILT_IN_VA_START:
5437 return lookup_attribute ("type generic",
5438 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5444 /* Subroutine of the various build_*_call functions. Overload resolution
5445 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5446 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5447 bitmask of various LOOKUP_* flags which apply to the call itself. */
5450 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5453 const VEC(tree,gc) *args = cand->args;
5454 tree first_arg = cand->first_arg;
5455 conversion **convs = cand->convs;
5457 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5462 unsigned int arg_index = 0;
5466 bool already_used = false;
5468 /* In a template, there is no need to perform all of the work that
5469 is normally done. We are only interested in the type of the call
5470 expression, i.e., the return type of the function. Any semantic
5471 errors will be deferred until the template is instantiated. */
5472 if (processing_template_decl)
5476 const tree *argarray;
5479 return_type = TREE_TYPE (TREE_TYPE (fn));
5480 nargs = VEC_length (tree, args);
5481 if (first_arg == NULL_TREE)
5482 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5490 alcarray = XALLOCAVEC (tree, nargs);
5491 alcarray[0] = first_arg;
5492 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5493 alcarray[ix + 1] = arg;
5494 argarray = alcarray;
5496 expr = build_call_array_loc (input_location,
5497 return_type, build_addr_func (fn), nargs,
5499 if (TREE_THIS_VOLATILE (fn) && cfun)
5500 current_function_returns_abnormally = 1;
5501 if (!VOID_TYPE_P (return_type))
5502 require_complete_type (return_type);
5503 return convert_from_reference (expr);
5506 /* Give any warnings we noticed during overload resolution. */
5509 struct candidate_warning *w;
5510 for (w = cand->warnings; w; w = w->next)
5511 joust (cand, w->loser, 1);
5514 /* Make =delete work with SFINAE. */
5515 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5516 return error_mark_node;
5518 if (DECL_FUNCTION_MEMBER_P (fn))
5520 /* If FN is a template function, two cases must be considered.
5525 template <class T> void f();
5527 template <class T> struct B {
5531 struct C : A, B<int> {
5533 using B<int>::g; // #2
5536 In case #1 where `A::f' is a member template, DECL_ACCESS is
5537 recorded in the primary template but not in its specialization.
5538 We check access of FN using its primary template.
5540 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5541 because it is a member of class template B, DECL_ACCESS is
5542 recorded in the specialization `B<int>::g'. We cannot use its
5543 primary template because `B<T>::g' and `B<int>::g' may have
5544 different access. */
5545 if (DECL_TEMPLATE_INFO (fn)
5546 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5547 perform_or_defer_access_check (cand->access_path,
5548 DECL_TI_TEMPLATE (fn), fn);
5550 perform_or_defer_access_check (cand->access_path, fn, fn);
5553 /* Find maximum size of vector to hold converted arguments. */
5554 parmlen = list_length (parm);
5555 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5556 if (parmlen > nargs)
5558 argarray = (tree *) alloca (nargs * sizeof (tree));
5560 /* The implicit parameters to a constructor are not considered by overload
5561 resolution, and must be of the proper type. */
5562 if (DECL_CONSTRUCTOR_P (fn))
5564 if (first_arg != NULL_TREE)
5566 argarray[j++] = first_arg;
5567 first_arg = NULL_TREE;
5571 argarray[j++] = VEC_index (tree, args, arg_index);
5574 parm = TREE_CHAIN (parm);
5575 /* We should never try to call the abstract constructor. */
5576 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5578 if (DECL_HAS_VTT_PARM_P (fn))
5580 argarray[j++] = VEC_index (tree, args, arg_index);
5582 parm = TREE_CHAIN (parm);
5585 /* Bypass access control for 'this' parameter. */
5586 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5588 tree parmtype = TREE_VALUE (parm);
5589 tree arg = (first_arg != NULL_TREE
5591 : VEC_index (tree, args, arg_index));
5592 tree argtype = TREE_TYPE (arg);
5596 if (convs[i]->bad_p)
5598 if (complain & tf_error)
5599 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5600 TREE_TYPE (argtype), fn);
5602 return error_mark_node;
5605 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5606 X is called for an object that is not of type X, or of a type
5607 derived from X, the behavior is undefined.
5609 So we can assume that anything passed as 'this' is non-null, and
5610 optimize accordingly. */
5611 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5612 /* Convert to the base in which the function was declared. */
5613 gcc_assert (cand->conversion_path != NULL_TREE);
5614 converted_arg = build_base_path (PLUS_EXPR,
5616 cand->conversion_path,
5618 /* Check that the base class is accessible. */
5619 if (!accessible_base_p (TREE_TYPE (argtype),
5620 BINFO_TYPE (cand->conversion_path), true))
5621 error ("%qT is not an accessible base of %qT",
5622 BINFO_TYPE (cand->conversion_path),
5623 TREE_TYPE (argtype));
5624 /* If fn was found by a using declaration, the conversion path
5625 will be to the derived class, not the base declaring fn. We
5626 must convert from derived to base. */
5627 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5628 TREE_TYPE (parmtype), ba_unique, NULL);
5629 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5632 argarray[j++] = converted_arg;
5633 parm = TREE_CHAIN (parm);
5634 if (first_arg != NULL_TREE)
5635 first_arg = NULL_TREE;
5642 gcc_assert (first_arg == NULL_TREE);
5643 for (; arg_index < VEC_length (tree, args) && parm;
5644 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5646 tree type = TREE_VALUE (parm);
5650 /* Don't make a copy here if build_call is going to. */
5651 if (conv->kind == ck_rvalue
5652 && COMPLETE_TYPE_P (complete_type (type))
5653 && !TREE_ADDRESSABLE (type))
5654 conv = conv->u.next;
5656 /* Warn about initializer_list deduction that isn't currently in the
5658 if (cxx_dialect > cxx98
5659 && flag_deduce_init_list
5660 && cand->template_decl
5661 && is_std_init_list (non_reference (type)))
5663 tree tmpl = TI_TEMPLATE (cand->template_decl);
5664 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
5665 tree patparm = get_pattern_parm (realparm, tmpl);
5667 if (!is_std_init_list (non_reference (TREE_TYPE (patparm))))
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,
5780 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5784 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5786 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5788 tree to = stabilize_reference
5789 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
5790 tree type = TREE_TYPE (to);
5791 tree as_base = CLASSTYPE_AS_BASE (type);
5792 tree arg = argarray[1];
5794 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5796 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
5797 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5801 /* We must only copy the non-tail padding parts.
5802 Use __builtin_memcpy for the bitwise copy.
5803 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5804 instead of an explicit call to memcpy. */
5806 tree arg0, arg1, arg2, t;
5807 tree test = NULL_TREE;
5809 arg2 = TYPE_SIZE_UNIT (as_base);
5811 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5813 if (!can_trust_pointer_alignment ())
5815 /* If we can't be sure about pointer alignment, a call
5816 to __builtin_memcpy is expanded as a call to memcpy, which
5817 is invalid with identical args. Otherwise it is
5818 expanded as a block move, which should be safe. */
5819 arg0 = save_expr (arg0);
5820 arg1 = save_expr (arg1);
5821 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5823 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5824 t = build_call_n (t, 3, arg0, arg1, arg2);
5826 t = convert (TREE_TYPE (arg0), t);
5828 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5829 val = cp_build_indirect_ref (t, 0, complain);
5830 TREE_NO_WARNING (val) = 1;
5839 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5842 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5845 gcc_assert (binfo && binfo != error_mark_node);
5847 /* Warn about deprecated virtual functions now, since we're about
5848 to throw away the decl. */
5849 if (TREE_DEPRECATED (fn))
5850 warn_deprecated_use (fn, NULL_TREE);
5852 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5853 if (TREE_SIDE_EFFECTS (argarray[0]))
5854 argarray[0] = save_expr (argarray[0]);
5855 t = build_pointer_type (TREE_TYPE (fn));
5856 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5857 fn = build_java_interface_fn_ref (fn, argarray[0]);
5859 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5863 fn = build_addr_func (fn);
5865 return build_cxx_call (fn, nargs, argarray);
5868 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5869 This function performs no overload resolution, conversion, or other
5870 high-level operations. */
5873 build_cxx_call (tree fn, int nargs, tree *argarray)
5877 fn = build_call_a (fn, nargs, argarray);
5879 /* If this call might throw an exception, note that fact. */
5880 fndecl = get_callee_fndecl (fn);
5881 if ((!fndecl || !TREE_NOTHROW (fndecl))
5882 && at_function_scope_p ()
5884 cp_function_chain->can_throw = 1;
5886 /* Check that arguments to builtin functions match the expectations. */
5888 && DECL_BUILT_IN (fndecl)
5889 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5890 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5891 return error_mark_node;
5893 /* Some built-in function calls will be evaluated at compile-time in
5895 fn = fold_if_not_in_template (fn);
5897 if (VOID_TYPE_P (TREE_TYPE (fn)))
5900 fn = require_complete_type (fn);
5901 if (fn == error_mark_node)
5902 return error_mark_node;
5904 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5905 fn = build_cplus_new (TREE_TYPE (fn), fn);
5906 return convert_from_reference (fn);
5909 static GTY(()) tree java_iface_lookup_fn;
5911 /* Make an expression which yields the address of the Java interface
5912 method FN. This is achieved by generating a call to libjava's
5913 _Jv_LookupInterfaceMethodIdx(). */
5916 build_java_interface_fn_ref (tree fn, tree instance)
5918 tree lookup_fn, method, idx;
5919 tree klass_ref, iface, iface_ref;
5922 if (!java_iface_lookup_fn)
5924 tree endlink = build_void_list_node ();
5925 tree t = tree_cons (NULL_TREE, ptr_type_node,
5926 tree_cons (NULL_TREE, ptr_type_node,
5927 tree_cons (NULL_TREE, java_int_type_node,
5929 java_iface_lookup_fn
5930 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5931 build_function_type (ptr_type_node, t),
5932 0, NOT_BUILT_IN, NULL, NULL_TREE);
5935 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5936 This is the first entry in the vtable. */
5937 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5938 tf_warning_or_error),
5941 /* Get the java.lang.Class pointer for the interface being called. */
5942 iface = DECL_CONTEXT (fn);
5943 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5944 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5945 || DECL_CONTEXT (iface_ref) != iface)
5947 error ("could not find class$ field in java interface type %qT",
5949 return error_mark_node;
5951 iface_ref = build_address (iface_ref);
5952 iface_ref = convert (build_pointer_type (iface), iface_ref);
5954 /* Determine the itable index of FN. */
5956 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5958 if (!DECL_VIRTUAL_P (method))
5964 idx = build_int_cst (NULL_TREE, i);
5966 lookup_fn = build1 (ADDR_EXPR,
5967 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5968 java_iface_lookup_fn);
5969 return build_call_nary (ptr_type_node, lookup_fn,
5970 3, klass_ref, iface_ref, idx);
5973 /* Returns the value to use for the in-charge parameter when making a
5974 call to a function with the indicated NAME.
5976 FIXME:Can't we find a neater way to do this mapping? */
5979 in_charge_arg_for_name (tree name)
5981 if (name == base_ctor_identifier
5982 || name == base_dtor_identifier)
5983 return integer_zero_node;
5984 else if (name == complete_ctor_identifier)
5985 return integer_one_node;
5986 else if (name == complete_dtor_identifier)
5987 return integer_two_node;
5988 else if (name == deleting_dtor_identifier)
5989 return integer_three_node;
5991 /* This function should only be called with one of the names listed
5997 /* Build a call to a constructor, destructor, or an assignment
5998 operator for INSTANCE, an expression with class type. NAME
5999 indicates the special member function to call; *ARGS are the
6000 arguments. ARGS may be NULL. This may change ARGS. BINFO
6001 indicates the base of INSTANCE that is to be passed as the `this'
6002 parameter to the member function called.
6004 FLAGS are the LOOKUP_* flags to use when processing the call.
6006 If NAME indicates a complete object constructor, INSTANCE may be
6007 NULL_TREE. In this case, the caller will call build_cplus_new to
6008 store the newly constructed object into a VAR_DECL. */
6011 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6012 tree binfo, int flags, tsubst_flags_t complain)
6015 /* The type of the subobject to be constructed or destroyed. */
6017 VEC(tree,gc) *allocated = NULL;
6020 gcc_assert (name == complete_ctor_identifier
6021 || name == base_ctor_identifier
6022 || name == complete_dtor_identifier
6023 || name == base_dtor_identifier
6024 || name == deleting_dtor_identifier
6025 || name == ansi_assopname (NOP_EXPR));
6028 /* Resolve the name. */
6029 if (!complete_type_or_else (binfo, NULL_TREE))
6030 return error_mark_node;
6032 binfo = TYPE_BINFO (binfo);
6035 gcc_assert (binfo != NULL_TREE);
6037 class_type = BINFO_TYPE (binfo);
6039 /* Handle the special case where INSTANCE is NULL_TREE. */
6040 if (name == complete_ctor_identifier && !instance)
6042 instance = build_int_cst (build_pointer_type (class_type), 0);
6043 instance = build1 (INDIRECT_REF, class_type, instance);
6047 if (name == complete_dtor_identifier
6048 || name == base_dtor_identifier
6049 || name == deleting_dtor_identifier)
6050 gcc_assert (args == NULL || VEC_empty (tree, *args));
6052 /* Convert to the base class, if necessary. */
6053 if (!same_type_ignoring_top_level_qualifiers_p
6054 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6056 if (name != ansi_assopname (NOP_EXPR))
6057 /* For constructors and destructors, either the base is
6058 non-virtual, or it is virtual but we are doing the
6059 conversion from a constructor or destructor for the
6060 complete object. In either case, we can convert
6062 instance = convert_to_base_statically (instance, binfo);
6064 /* However, for assignment operators, we must convert
6065 dynamically if the base is virtual. */
6066 instance = build_base_path (PLUS_EXPR, instance,
6067 binfo, /*nonnull=*/1);
6071 gcc_assert (instance != NULL_TREE);
6073 fns = lookup_fnfields (binfo, name, 1);
6075 /* When making a call to a constructor or destructor for a subobject
6076 that uses virtual base classes, pass down a pointer to a VTT for
6078 if ((name == base_ctor_identifier
6079 || name == base_dtor_identifier)
6080 && CLASSTYPE_VBASECLASSES (class_type))
6085 /* If the current function is a complete object constructor
6086 or destructor, then we fetch the VTT directly.
6087 Otherwise, we look it up using the VTT we were given. */
6088 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6089 vtt = decay_conversion (vtt);
6090 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6091 build2 (EQ_EXPR, boolean_type_node,
6092 current_in_charge_parm, integer_zero_node),
6095 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6096 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6097 BINFO_SUBVTT_INDEX (binfo));
6101 allocated = make_tree_vector ();
6105 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6108 ret = build_new_method_call (instance, fns, args,
6109 TYPE_BINFO (BINFO_TYPE (binfo)),
6113 if (allocated != NULL)
6114 release_tree_vector (allocated);
6119 /* Return the NAME, as a C string. The NAME indicates a function that
6120 is a member of TYPE. *FREE_P is set to true if the caller must
6121 free the memory returned.
6123 Rather than go through all of this, we should simply set the names
6124 of constructors and destructors appropriately, and dispense with
6125 ctor_identifier, dtor_identifier, etc. */
6128 name_as_c_string (tree name, tree type, bool *free_p)
6132 /* Assume that we will not allocate memory. */
6134 /* Constructors and destructors are special. */
6135 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6138 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6139 /* For a destructor, add the '~'. */
6140 if (name == complete_dtor_identifier
6141 || name == base_dtor_identifier
6142 || name == deleting_dtor_identifier)
6144 pretty_name = concat ("~", pretty_name, NULL);
6145 /* Remember that we need to free the memory allocated. */
6149 else if (IDENTIFIER_TYPENAME_P (name))
6151 pretty_name = concat ("operator ",
6152 type_as_string_translate (TREE_TYPE (name),
6153 TFF_PLAIN_IDENTIFIER),
6155 /* Remember that we need to free the memory allocated. */
6159 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6164 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6165 be set, upon return, to the function called. ARGS may be NULL.
6166 This may change ARGS. */
6169 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6170 tree conversion_path, int flags,
6171 tree *fn_p, tsubst_flags_t complain)
6173 struct z_candidate *candidates = 0, *cand;
6174 tree explicit_targs = NULL_TREE;
6175 tree basetype = NULL_TREE;
6178 tree first_mem_arg = NULL_TREE;
6181 bool skip_first_for_error;
6182 VEC(tree,gc) *user_args;
6186 int template_only = 0;
6190 VEC(tree,gc) *orig_args = NULL;
6193 gcc_assert (instance != NULL_TREE);
6195 /* We don't know what function we're going to call, yet. */
6199 if (error_operand_p (instance)
6200 || error_operand_p (fns))
6201 return error_mark_node;
6203 if (!BASELINK_P (fns))
6205 if (complain & tf_error)
6206 error ("call to non-function %qD", fns);
6207 return error_mark_node;
6210 orig_instance = instance;
6213 /* Dismantle the baselink to collect all the information we need. */
6214 if (!conversion_path)
6215 conversion_path = BASELINK_BINFO (fns);
6216 access_binfo = BASELINK_ACCESS_BINFO (fns);
6217 optype = BASELINK_OPTYPE (fns);
6218 fns = BASELINK_FUNCTIONS (fns);
6219 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6221 explicit_targs = TREE_OPERAND (fns, 1);
6222 fns = TREE_OPERAND (fns, 0);
6225 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6226 || TREE_CODE (fns) == TEMPLATE_DECL
6227 || TREE_CODE (fns) == OVERLOAD);
6228 fn = get_first_fn (fns);
6229 name = DECL_NAME (fn);
6231 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6232 gcc_assert (CLASS_TYPE_P (basetype));
6234 if (processing_template_decl)
6236 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6237 instance = build_non_dependent_expr (instance);
6239 make_args_non_dependent (*args);
6242 /* Figure out whether to skip the first argument for the error
6243 message we will display to users if an error occurs. We don't
6244 want to display any compiler-generated arguments. The "this"
6245 pointer hasn't been added yet. However, we must remove the VTT
6246 pointer if this is a call to a base-class constructor or
6248 skip_first_for_error = false;
6249 user_args = args == NULL ? NULL : *args;
6250 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6252 /* Callers should explicitly indicate whether they want to construct
6253 the complete object or just the part without virtual bases. */
6254 gcc_assert (name != ctor_identifier);
6255 /* Similarly for destructors. */
6256 gcc_assert (name != dtor_identifier);
6257 /* Remove the VTT pointer, if present. */
6258 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6259 && CLASSTYPE_VBASECLASSES (basetype))
6260 skip_first_for_error = true;
6263 /* Process the argument list. */
6264 if (args != NULL && *args != NULL)
6266 *args = resolve_args (*args);
6268 return error_mark_node;
6271 instance_ptr = build_this (instance);
6273 /* It's OK to call destructors and constructors on cv-qualified objects.
6274 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6276 if (DECL_DESTRUCTOR_P (fn)
6277 || DECL_CONSTRUCTOR_P (fn))
6279 tree type = build_pointer_type (basetype);
6280 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6281 instance_ptr = build_nop (type, instance_ptr);
6283 if (DECL_DESTRUCTOR_P (fn))
6284 name = complete_dtor_identifier;
6286 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6287 initializer, not T({ }). If the type doesn't have a list ctor,
6288 break apart the list into separate ctor args. */
6289 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6290 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6291 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6292 && !TYPE_HAS_LIST_CTOR (basetype))
6294 gcc_assert (VEC_length (tree, *args) == 1);
6295 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6298 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6299 first_mem_arg = instance_ptr;
6301 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6302 p = conversion_obstack_alloc (0);
6304 for (fn = fns; fn; fn = OVL_NEXT (fn))
6306 tree t = OVL_CURRENT (fn);
6307 tree this_first_arg;
6309 /* We can end up here for copy-init of same or base class. */
6310 if ((flags & LOOKUP_ONLYCONVERTING)
6311 && DECL_NONCONVERTING_P (t))
6314 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6315 this_first_arg = first_mem_arg;
6317 this_first_arg = NULL_TREE;
6319 if (TREE_CODE (t) == TEMPLATE_DECL)
6320 /* A member template. */
6321 add_template_candidate (&candidates, t,
6325 args == NULL ? NULL : *args,
6331 else if (! template_only)
6332 add_function_candidate (&candidates, t,
6335 args == NULL ? NULL : *args,
6341 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6344 if (complain & tf_error)
6346 if (!COMPLETE_TYPE_P (basetype))
6347 cxx_incomplete_type_error (instance_ptr, basetype);
6354 pretty_name = name_as_c_string (name, basetype, &free_p);
6355 arglist = build_tree_list_vec (user_args);
6356 if (skip_first_for_error)
6357 arglist = TREE_CHAIN (arglist);
6358 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6359 basetype, pretty_name, arglist,
6360 TREE_TYPE (TREE_TYPE (instance_ptr)));
6364 print_z_candidates (candidates);
6366 call = error_mark_node;
6370 cand = tourney (candidates);
6377 if (complain & tf_error)
6379 pretty_name = name_as_c_string (name, basetype, &free_p);
6380 arglist = build_tree_list_vec (user_args);
6381 if (skip_first_for_error)
6382 arglist = TREE_CHAIN (arglist);
6383 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6385 print_z_candidates (candidates);
6389 call = error_mark_node;
6395 if (!(flags & LOOKUP_NONVIRTUAL)
6396 && DECL_PURE_VIRTUAL_P (fn)
6397 && instance == current_class_ref
6398 && (DECL_CONSTRUCTOR_P (current_function_decl)
6399 || DECL_DESTRUCTOR_P (current_function_decl))
6400 && (complain & tf_warning))
6401 /* This is not an error, it is runtime undefined
6403 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6404 "abstract virtual %q#D called from constructor"
6405 : "abstract virtual %q#D called from destructor"),
6408 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6409 && is_dummy_object (instance_ptr))
6411 if (complain & tf_error)
6412 error ("cannot call member function %qD without object",
6414 call = error_mark_node;
6418 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6419 && resolves_to_fixed_type_p (instance, 0))
6420 flags |= LOOKUP_NONVIRTUAL;
6421 /* Now we know what function is being called. */
6424 /* Build the actual CALL_EXPR. */
6425 call = build_over_call (cand, flags, complain);
6426 /* In an expression of the form `a->f()' where `f' turns
6427 out to be a static member function, `a' is
6428 none-the-less evaluated. */
6429 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6430 && !is_dummy_object (instance_ptr)
6431 && TREE_SIDE_EFFECTS (instance_ptr))
6432 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6433 instance_ptr, call);
6434 else if (call != error_mark_node
6435 && DECL_DESTRUCTOR_P (cand->fn)
6436 && !VOID_TYPE_P (TREE_TYPE (call)))
6437 /* An explicit call of the form "x->~X()" has type
6438 "void". However, on platforms where destructors
6439 return "this" (i.e., those where
6440 targetm.cxx.cdtor_returns_this is true), such calls
6441 will appear to have a return value of pointer type
6442 to the low-level call machinery. We do not want to
6443 change the low-level machinery, since we want to be
6444 able to optimize "delete f()" on such platforms as
6445 "operator delete(~X(f()))" (rather than generating
6446 "t = f(), ~X(t), operator delete (t)"). */
6447 call = build_nop (void_type_node, call);
6452 if (processing_template_decl && call != error_mark_node)
6454 bool cast_to_void = false;
6456 if (TREE_CODE (call) == COMPOUND_EXPR)
6457 call = TREE_OPERAND (call, 1);
6458 else if (TREE_CODE (call) == NOP_EXPR)
6460 cast_to_void = true;
6461 call = TREE_OPERAND (call, 0);
6463 if (TREE_CODE (call) == INDIRECT_REF)
6464 call = TREE_OPERAND (call, 0);
6465 call = (build_min_non_dep_call_vec
6467 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6468 orig_instance, orig_fns, NULL_TREE),
6470 call = convert_from_reference (call);
6472 call = build_nop (void_type_node, call);
6475 /* Free all the conversions we allocated. */
6476 obstack_free (&conversion_obstack, p);
6478 if (orig_args != NULL)
6479 release_tree_vector (orig_args);
6484 /* Returns true iff standard conversion sequence ICS1 is a proper
6485 subsequence of ICS2. */
6488 is_subseq (conversion *ics1, conversion *ics2)
6490 /* We can assume that a conversion of the same code
6491 between the same types indicates a subsequence since we only get
6492 here if the types we are converting from are the same. */
6494 while (ics1->kind == ck_rvalue
6495 || ics1->kind == ck_lvalue)
6496 ics1 = ics1->u.next;
6500 while (ics2->kind == ck_rvalue
6501 || ics2->kind == ck_lvalue)
6502 ics2 = ics2->u.next;
6504 if (ics2->kind == ck_user
6505 || ics2->kind == ck_ambig
6506 || ics2->kind == ck_identity)
6507 /* At this point, ICS1 cannot be a proper subsequence of
6508 ICS2. We can get a USER_CONV when we are comparing the
6509 second standard conversion sequence of two user conversion
6513 ics2 = ics2->u.next;
6515 if (ics2->kind == ics1->kind
6516 && same_type_p (ics2->type, ics1->type)
6517 && same_type_p (ics2->u.next->type,
6518 ics1->u.next->type))
6523 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6524 be any _TYPE nodes. */
6527 is_properly_derived_from (tree derived, tree base)
6529 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6532 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6533 considers every class derived from itself. */
6534 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6535 && DERIVED_FROM_P (base, derived));
6538 /* We build the ICS for an implicit object parameter as a pointer
6539 conversion sequence. However, such a sequence should be compared
6540 as if it were a reference conversion sequence. If ICS is the
6541 implicit conversion sequence for an implicit object parameter,
6542 modify it accordingly. */
6545 maybe_handle_implicit_object (conversion **ics)
6549 /* [over.match.funcs]
6551 For non-static member functions, the type of the
6552 implicit object parameter is "reference to cv X"
6553 where X is the class of which the function is a
6554 member and cv is the cv-qualification on the member
6555 function declaration. */
6556 conversion *t = *ics;
6557 tree reference_type;
6559 /* The `this' parameter is a pointer to a class type. Make the
6560 implicit conversion talk about a reference to that same class
6562 reference_type = TREE_TYPE (t->type);
6563 reference_type = build_reference_type (reference_type);
6565 if (t->kind == ck_qual)
6567 if (t->kind == ck_ptr)
6569 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6570 t = direct_reference_binding (reference_type, t);
6572 t->rvaluedness_matches_p = 0;
6577 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6578 and return the initial reference binding conversion. Otherwise,
6579 leave *ICS unchanged and return NULL. */
6582 maybe_handle_ref_bind (conversion **ics)
6584 if ((*ics)->kind == ck_ref_bind)
6586 conversion *old_ics = *ics;
6587 *ics = old_ics->u.next;
6588 (*ics)->user_conv_p = old_ics->user_conv_p;
6595 /* Compare two implicit conversion sequences according to the rules set out in
6596 [over.ics.rank]. Return values:
6598 1: ics1 is better than ics2
6599 -1: ics2 is better than ics1
6600 0: ics1 and ics2 are indistinguishable */
6603 compare_ics (conversion *ics1, conversion *ics2)
6609 tree deref_from_type1 = NULL_TREE;
6610 tree deref_from_type2 = NULL_TREE;
6611 tree deref_to_type1 = NULL_TREE;
6612 tree deref_to_type2 = NULL_TREE;
6613 conversion_rank rank1, rank2;
6615 /* REF_BINDING is nonzero if the result of the conversion sequence
6616 is a reference type. In that case REF_CONV is the reference
6617 binding conversion. */
6618 conversion *ref_conv1;
6619 conversion *ref_conv2;
6621 /* Handle implicit object parameters. */
6622 maybe_handle_implicit_object (&ics1);
6623 maybe_handle_implicit_object (&ics2);
6625 /* Handle reference parameters. */
6626 ref_conv1 = maybe_handle_ref_bind (&ics1);
6627 ref_conv2 = maybe_handle_ref_bind (&ics2);
6629 /* List-initialization sequence L1 is a better conversion sequence than
6630 list-initialization sequence L2 if L1 converts to
6631 std::initializer_list<X> for some X and L2 does not. */
6632 if (ics1->kind == ck_list && ics2->kind != ck_list)
6634 if (ics2->kind == ck_list && ics1->kind != ck_list)
6639 When comparing the basic forms of implicit conversion sequences (as
6640 defined in _over.best.ics_)
6642 --a standard conversion sequence (_over.ics.scs_) is a better
6643 conversion sequence than a user-defined conversion sequence
6644 or an ellipsis conversion sequence, and
6646 --a user-defined conversion sequence (_over.ics.user_) is a
6647 better conversion sequence than an ellipsis conversion sequence
6648 (_over.ics.ellipsis_). */
6649 rank1 = CONVERSION_RANK (ics1);
6650 rank2 = CONVERSION_RANK (ics2);
6654 else if (rank1 < rank2)
6657 if (rank1 == cr_bad)
6659 /* XXX Isn't this an extension? */
6660 /* Both ICS are bad. We try to make a decision based on what
6661 would have happened if they'd been good. */
6662 if (ics1->user_conv_p > ics2->user_conv_p
6663 || ics1->rank > ics2->rank)
6665 else if (ics1->user_conv_p < ics2->user_conv_p
6666 || ics1->rank < ics2->rank)
6669 /* We couldn't make up our minds; try to figure it out below. */
6672 if (ics1->ellipsis_p || ics1->kind == ck_list)
6673 /* Both conversions are ellipsis conversions or both are building a
6674 std::initializer_list. */
6677 /* User-defined conversion sequence U1 is a better conversion sequence
6678 than another user-defined conversion sequence U2 if they contain the
6679 same user-defined conversion operator or constructor and if the sec-
6680 ond standard conversion sequence of U1 is better than the second
6681 standard conversion sequence of U2. */
6683 if (ics1->user_conv_p)
6688 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6689 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6691 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6692 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6695 if (t1->cand->fn != t2->cand->fn)
6698 /* We can just fall through here, after setting up
6699 FROM_TYPE1 and FROM_TYPE2. */
6700 from_type1 = t1->type;
6701 from_type2 = t2->type;
6708 /* We're dealing with two standard conversion sequences.
6712 Standard conversion sequence S1 is a better conversion
6713 sequence than standard conversion sequence S2 if
6715 --S1 is a proper subsequence of S2 (comparing the conversion
6716 sequences in the canonical form defined by _over.ics.scs_,
6717 excluding any Lvalue Transformation; the identity
6718 conversion sequence is considered to be a subsequence of
6719 any non-identity conversion sequence */
6722 while (t1->kind != ck_identity)
6724 from_type1 = t1->type;
6727 while (t2->kind != ck_identity)
6729 from_type2 = t2->type;
6732 /* One sequence can only be a subsequence of the other if they start with
6733 the same type. They can start with different types when comparing the
6734 second standard conversion sequence in two user-defined conversion
6736 if (same_type_p (from_type1, from_type2))
6738 if (is_subseq (ics1, ics2))
6740 if (is_subseq (ics2, ics1))
6748 --the rank of S1 is better than the rank of S2 (by the rules
6751 Standard conversion sequences are ordered by their ranks: an Exact
6752 Match is a better conversion than a Promotion, which is a better
6753 conversion than a Conversion.
6755 Two conversion sequences with the same rank are indistinguishable
6756 unless one of the following rules applies:
6758 --A conversion that is not a conversion of a pointer, or pointer
6759 to member, to bool is better than another conversion that is such
6762 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6763 so that we do not have to check it explicitly. */
6764 if (ics1->rank < ics2->rank)
6766 else if (ics2->rank < ics1->rank)
6769 to_type1 = ics1->type;
6770 to_type2 = ics2->type;
6772 /* A conversion from scalar arithmetic type to complex is worse than a
6773 conversion between scalar arithmetic types. */
6774 if (same_type_p (from_type1, from_type2)
6775 && ARITHMETIC_TYPE_P (from_type1)
6776 && ARITHMETIC_TYPE_P (to_type1)
6777 && ARITHMETIC_TYPE_P (to_type2)
6778 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6779 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6781 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6787 if (TYPE_PTR_P (from_type1)
6788 && TYPE_PTR_P (from_type2)
6789 && TYPE_PTR_P (to_type1)
6790 && TYPE_PTR_P (to_type2))
6792 deref_from_type1 = TREE_TYPE (from_type1);
6793 deref_from_type2 = TREE_TYPE (from_type2);
6794 deref_to_type1 = TREE_TYPE (to_type1);
6795 deref_to_type2 = TREE_TYPE (to_type2);
6797 /* The rules for pointers to members A::* are just like the rules
6798 for pointers A*, except opposite: if B is derived from A then
6799 A::* converts to B::*, not vice versa. For that reason, we
6800 switch the from_ and to_ variables here. */
6801 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6802 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6803 || (TYPE_PTRMEMFUNC_P (from_type1)
6804 && TYPE_PTRMEMFUNC_P (from_type2)
6805 && TYPE_PTRMEMFUNC_P (to_type1)
6806 && TYPE_PTRMEMFUNC_P (to_type2)))
6808 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6809 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6810 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6811 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6814 if (deref_from_type1 != NULL_TREE
6815 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6816 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6818 /* This was one of the pointer or pointer-like conversions.
6822 --If class B is derived directly or indirectly from class A,
6823 conversion of B* to A* is better than conversion of B* to
6824 void*, and conversion of A* to void* is better than
6825 conversion of B* to void*. */
6826 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6827 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6829 if (is_properly_derived_from (deref_from_type1,
6832 else if (is_properly_derived_from (deref_from_type2,
6836 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6837 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6839 if (same_type_p (deref_from_type1, deref_from_type2))
6841 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6843 if (is_properly_derived_from (deref_from_type1,
6847 /* We know that DEREF_TO_TYPE1 is `void' here. */
6848 else if (is_properly_derived_from (deref_from_type1,
6853 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6854 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6858 --If class B is derived directly or indirectly from class A
6859 and class C is derived directly or indirectly from B,
6861 --conversion of C* to B* is better than conversion of C* to
6864 --conversion of B* to A* is better than conversion of C* to
6866 if (same_type_p (deref_from_type1, deref_from_type2))
6868 if (is_properly_derived_from (deref_to_type1,
6871 else if (is_properly_derived_from (deref_to_type2,
6875 else if (same_type_p (deref_to_type1, deref_to_type2))
6877 if (is_properly_derived_from (deref_from_type2,
6880 else if (is_properly_derived_from (deref_from_type1,
6886 else if (CLASS_TYPE_P (non_reference (from_type1))
6887 && same_type_p (from_type1, from_type2))
6889 tree from = non_reference (from_type1);
6893 --binding of an expression of type C to a reference of type
6894 B& is better than binding an expression of type C to a
6895 reference of type A&
6897 --conversion of C to B is better than conversion of C to A, */
6898 if (is_properly_derived_from (from, to_type1)
6899 && is_properly_derived_from (from, to_type2))
6901 if (is_properly_derived_from (to_type1, to_type2))
6903 else if (is_properly_derived_from (to_type2, to_type1))
6907 else if (CLASS_TYPE_P (non_reference (to_type1))
6908 && same_type_p (to_type1, to_type2))
6910 tree to = non_reference (to_type1);
6914 --binding of an expression of type B to a reference of type
6915 A& is better than binding an expression of type C to a
6916 reference of type A&,
6918 --conversion of B to A is better than conversion of C to A */
6919 if (is_properly_derived_from (from_type1, to)
6920 && is_properly_derived_from (from_type2, to))
6922 if (is_properly_derived_from (from_type2, from_type1))
6924 else if (is_properly_derived_from (from_type1, from_type2))
6931 --S1 and S2 differ only in their qualification conversion and yield
6932 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6933 qualification signature of type T1 is a proper subset of the cv-
6934 qualification signature of type T2 */
6935 if (ics1->kind == ck_qual
6936 && ics2->kind == ck_qual
6937 && same_type_p (from_type1, from_type2))
6939 int result = comp_cv_qual_signature (to_type1, to_type2);
6946 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6947 to an implicit object parameter, and either S1 binds an lvalue reference
6948 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6949 reference to an rvalue and S2 binds an lvalue reference
6950 (C++0x draft standard, 13.3.3.2)
6952 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6953 types to which the references refer are the same type except for
6954 top-level cv-qualifiers, and the type to which the reference
6955 initialized by S2 refers is more cv-qualified than the type to
6956 which the reference initialized by S1 refers */
6958 if (ref_conv1 && ref_conv2)
6960 if (!ref_conv1->this_p && !ref_conv2->this_p
6961 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6962 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6964 if (ref_conv1->rvaluedness_matches_p)
6966 if (ref_conv2->rvaluedness_matches_p)
6970 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6971 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6972 TREE_TYPE (ref_conv1->type));
6975 /* Neither conversion sequence is better than the other. */
6979 /* The source type for this standard conversion sequence. */
6982 source_type (conversion *t)
6984 for (;; t = t->u.next)
6986 if (t->kind == ck_user
6987 || t->kind == ck_ambig
6988 || t->kind == ck_identity)
6994 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6995 a pointer to LOSER and re-running joust to produce the warning if WINNER
6996 is actually used. */
6999 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7001 candidate_warning *cw = (candidate_warning *)
7002 conversion_obstack_alloc (sizeof (candidate_warning));
7004 cw->next = winner->warnings;
7005 winner->warnings = cw;
7008 /* Compare two candidates for overloading as described in
7009 [over.match.best]. Return values:
7011 1: cand1 is better than cand2
7012 -1: cand2 is better than cand1
7013 0: cand1 and cand2 are indistinguishable */
7016 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7019 int off1 = 0, off2 = 0;
7023 /* Candidates that involve bad conversions are always worse than those
7025 if (cand1->viable > cand2->viable)
7027 if (cand1->viable < cand2->viable)
7030 /* If we have two pseudo-candidates for conversions to the same type,
7031 or two candidates for the same function, arbitrarily pick one. */
7032 if (cand1->fn == cand2->fn
7033 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7036 /* a viable function F1
7037 is defined to be a better function than another viable function F2 if
7038 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7039 ICSi(F2), and then */
7041 /* for some argument j, ICSj(F1) is a better conversion sequence than
7044 /* For comparing static and non-static member functions, we ignore
7045 the implicit object parameter of the non-static function. The
7046 standard says to pretend that the static function has an object
7047 parm, but that won't work with operator overloading. */
7048 len = cand1->num_convs;
7049 if (len != cand2->num_convs)
7051 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7052 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7054 gcc_assert (static_1 != static_2);
7065 for (i = 0; i < len; ++i)
7067 conversion *t1 = cand1->convs[i + off1];
7068 conversion *t2 = cand2->convs[i + off2];
7069 int comp = compare_ics (t1, t2);
7074 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7075 == cr_std + cr_promotion)
7076 && t1->kind == ck_std
7077 && t2->kind == ck_std
7078 && TREE_CODE (t1->type) == INTEGER_TYPE
7079 && TREE_CODE (t2->type) == INTEGER_TYPE
7080 && (TYPE_PRECISION (t1->type)
7081 == TYPE_PRECISION (t2->type))
7082 && (TYPE_UNSIGNED (t1->u.next->type)
7083 || (TREE_CODE (t1->u.next->type)
7086 tree type = t1->u.next->type;
7088 struct z_candidate *w, *l;
7090 type1 = t1->type, type2 = t2->type,
7091 w = cand1, l = cand2;
7093 type1 = t2->type, type2 = t1->type,
7094 w = cand2, l = cand1;
7098 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7099 type, type1, type2);
7100 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7106 if (winner && comp != winner)
7115 /* warn about confusing overload resolution for user-defined conversions,
7116 either between a constructor and a conversion op, or between two
7118 if (winner && warn_conversion && cand1->second_conv
7119 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7120 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7122 struct z_candidate *w, *l;
7123 bool give_warning = false;
7126 w = cand1, l = cand2;
7128 w = cand2, l = cand1;
7130 /* We don't want to complain about `X::operator T1 ()'
7131 beating `X::operator T2 () const', when T2 is a no less
7132 cv-qualified version of T1. */
7133 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7134 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7136 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7137 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7139 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7144 if (!comp_ptr_ttypes (t, f))
7145 give_warning = true;
7148 give_warning = true;
7154 tree source = source_type (w->convs[0]);
7155 if (! DECL_CONSTRUCTOR_P (w->fn))
7156 source = TREE_TYPE (source);
7157 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7158 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7159 source, w->second_conv->type))
7161 inform (input_location, " because conversion sequence for the argument is better");
7172 F1 is a non-template function and F2 is a template function
7175 if (!cand1->template_decl && cand2->template_decl)
7177 else if (cand1->template_decl && !cand2->template_decl)
7181 F1 and F2 are template functions and the function template for F1 is
7182 more specialized than the template for F2 according to the partial
7185 if (cand1->template_decl && cand2->template_decl)
7187 winner = more_specialized_fn
7188 (TI_TEMPLATE (cand1->template_decl),
7189 TI_TEMPLATE (cand2->template_decl),
7190 /* [temp.func.order]: The presence of unused ellipsis and default
7191 arguments has no effect on the partial ordering of function
7192 templates. add_function_candidate() will not have
7193 counted the "this" argument for constructors. */
7194 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7200 the context is an initialization by user-defined conversion (see
7201 _dcl.init_ and _over.match.user_) and the standard conversion
7202 sequence from the return type of F1 to the destination type (i.e.,
7203 the type of the entity being initialized) is a better conversion
7204 sequence than the standard conversion sequence from the return type
7205 of F2 to the destination type. */
7207 if (cand1->second_conv)
7209 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7214 /* Check whether we can discard a builtin candidate, either because we
7215 have two identical ones or matching builtin and non-builtin candidates.
7217 (Pedantically in the latter case the builtin which matched the user
7218 function should not be added to the overload set, but we spot it here.
7221 ... the builtin candidates include ...
7222 - do not have the same parameter type list as any non-template
7223 non-member candidate. */
7225 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7226 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7228 for (i = 0; i < len; ++i)
7229 if (!same_type_p (cand1->convs[i]->type,
7230 cand2->convs[i]->type))
7232 if (i == cand1->num_convs)
7234 if (cand1->fn == cand2->fn)
7235 /* Two built-in candidates; arbitrarily pick one. */
7237 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7238 /* cand1 is built-in; prefer cand2. */
7241 /* cand2 is built-in; prefer cand1. */
7246 /* If the two function declarations represent the same function (this can
7247 happen with declarations in multiple scopes and arg-dependent lookup),
7248 arbitrarily choose one. But first make sure the default args we're
7250 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7251 && equal_functions (cand1->fn, cand2->fn))
7253 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7254 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7256 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7258 for (i = 0; i < len; ++i)
7260 /* Don't crash if the fn is variadic. */
7263 parms1 = TREE_CHAIN (parms1);
7264 parms2 = TREE_CHAIN (parms2);
7268 parms1 = TREE_CHAIN (parms1);
7270 parms2 = TREE_CHAIN (parms2);
7274 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7275 TREE_PURPOSE (parms2)))
7279 permerror (input_location, "default argument mismatch in "
7280 "overload resolution");
7281 inform (input_location,
7282 " candidate 1: %q+#F", cand1->fn);
7283 inform (input_location,
7284 " candidate 2: %q+#F", cand2->fn);
7287 add_warning (cand1, cand2);
7290 parms1 = TREE_CHAIN (parms1);
7291 parms2 = TREE_CHAIN (parms2);
7299 /* Extension: If the worst conversion for one candidate is worse than the
7300 worst conversion for the other, take the first. */
7303 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7304 struct z_candidate *w = 0, *l = 0;
7306 for (i = 0; i < len; ++i)
7308 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7309 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7310 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7311 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7314 winner = 1, w = cand1, l = cand2;
7316 winner = -1, w = cand2, l = cand1;
7321 pedwarn (input_location, 0,
7322 "ISO C++ says that these are ambiguous, even "
7323 "though the worst conversion for the first is better than "
7324 "the worst conversion for the second:");
7325 print_z_candidate (_("candidate 1:"), w);
7326 print_z_candidate (_("candidate 2:"), l);
7334 gcc_assert (!winner);
7338 /* Given a list of candidates for overloading, find the best one, if any.
7339 This algorithm has a worst case of O(2n) (winner is last), and a best
7340 case of O(n/2) (totally ambiguous); much better than a sorting
7343 static struct z_candidate *
7344 tourney (struct z_candidate *candidates)
7346 struct z_candidate *champ = candidates, *challenger;
7348 int champ_compared_to_predecessor = 0;
7350 /* Walk through the list once, comparing each current champ to the next
7351 candidate, knocking out a candidate or two with each comparison. */
7353 for (challenger = champ->next; challenger; )
7355 fate = joust (champ, challenger, 0);
7357 challenger = challenger->next;
7362 champ = challenger->next;
7365 champ_compared_to_predecessor = 0;
7370 champ_compared_to_predecessor = 1;
7373 challenger = champ->next;
7377 /* Make sure the champ is better than all the candidates it hasn't yet
7378 been compared to. */
7380 for (challenger = candidates;
7382 && !(champ_compared_to_predecessor && challenger->next == champ);
7383 challenger = challenger->next)
7385 fate = joust (champ, challenger, 0);
7393 /* Returns nonzero if things of type FROM can be converted to TO. */
7396 can_convert (tree to, tree from)
7398 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7401 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7404 can_convert_arg (tree to, tree from, tree arg, int flags)
7410 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7411 p = conversion_obstack_alloc (0);
7413 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7415 ok_p = (t && !t->bad_p);
7417 /* Free all the conversions we allocated. */
7418 obstack_free (&conversion_obstack, p);
7423 /* Like can_convert_arg, but allows dubious conversions as well. */
7426 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7431 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7432 p = conversion_obstack_alloc (0);
7433 /* Try to perform the conversion. */
7434 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7436 /* Free all the conversions we allocated. */
7437 obstack_free (&conversion_obstack, p);
7442 /* Convert EXPR to TYPE. Return the converted expression.
7444 Note that we allow bad conversions here because by the time we get to
7445 this point we are committed to doing the conversion. If we end up
7446 doing a bad conversion, convert_like will complain. */
7449 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7454 if (error_operand_p (expr))
7455 return error_mark_node;
7457 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7458 p = conversion_obstack_alloc (0);
7460 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7466 if (complain & tf_error)
7468 /* If expr has unknown type, then it is an overloaded function.
7469 Call instantiate_type to get good error messages. */
7470 if (TREE_TYPE (expr) == unknown_type_node)
7471 instantiate_type (type, expr, complain);
7472 else if (invalid_nonstatic_memfn_p (expr, complain))
7473 /* We gave an error. */;
7475 error ("could not convert %qE to %qT", expr, type);
7477 expr = error_mark_node;
7479 else if (processing_template_decl)
7481 /* In a template, we are only concerned about determining the
7482 type of non-dependent expressions, so we do not have to
7483 perform the actual conversion. */
7484 if (TREE_TYPE (expr) != type)
7485 expr = build_nop (type, expr);
7488 expr = convert_like (conv, expr, complain);
7490 /* Free all the conversions we allocated. */
7491 obstack_free (&conversion_obstack, p);
7497 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7499 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7502 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7503 permitted. If the conversion is valid, the converted expression is
7504 returned. Otherwise, NULL_TREE is returned, except in the case
7505 that TYPE is a class type; in that case, an error is issued. If
7506 C_CAST_P is true, then this direction initialization is taking
7507 place as part of a static_cast being attempted as part of a C-style
7511 perform_direct_initialization_if_possible (tree type,
7514 tsubst_flags_t complain)
7519 if (type == error_mark_node || error_operand_p (expr))
7520 return error_mark_node;
7523 If the destination type is a (possibly cv-qualified) class type:
7525 -- If the initialization is direct-initialization ...,
7526 constructors are considered. ... If no constructor applies, or
7527 the overload resolution is ambiguous, the initialization is
7529 if (CLASS_TYPE_P (type))
7531 VEC(tree,gc) *args = make_tree_vector_single (expr);
7532 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7533 &args, type, LOOKUP_NORMAL, complain);
7534 release_tree_vector (args);
7535 return build_cplus_new (type, expr);
7538 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7539 p = conversion_obstack_alloc (0);
7541 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7544 if (!conv || conv->bad_p)
7547 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7548 /*issue_conversion_warnings=*/false,
7550 tf_warning_or_error);
7552 /* Free all the conversions we allocated. */
7553 obstack_free (&conversion_obstack, p);
7558 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7559 is being bound to a temporary. Create and return a new VAR_DECL
7560 with the indicated TYPE; this variable will store the value to
7561 which the reference is bound. */
7564 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7568 /* Create the variable. */
7569 var = create_temporary_var (type);
7571 /* Register the variable. */
7572 if (TREE_STATIC (decl))
7574 /* Namespace-scope or local static; give it a mangled name. */
7577 TREE_STATIC (var) = 1;
7578 name = mangle_ref_init_variable (decl);
7579 DECL_NAME (var) = name;
7580 SET_DECL_ASSEMBLER_NAME (var, name);
7581 var = pushdecl_top_level (var);
7584 /* Create a new cleanup level if necessary. */
7585 maybe_push_cleanup_level (type);
7590 /* EXPR is the initializer for a variable DECL of reference or
7591 std::initializer_list type. Create, push and return a new VAR_DECL
7592 for the initializer so that it will live as long as DECL. Any
7593 cleanup for the new variable is returned through CLEANUP, and the
7594 code to initialize the new variable is returned through INITP. */
7597 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7603 /* Create the temporary variable. */
7604 type = TREE_TYPE (expr);
7605 var = make_temporary_var_for_ref_to_temp (decl, type);
7606 layout_decl (var, 0);
7607 /* If the rvalue is the result of a function call it will be
7608 a TARGET_EXPR. If it is some other construct (such as a
7609 member access expression where the underlying object is
7610 itself the result of a function call), turn it into a
7611 TARGET_EXPR here. It is important that EXPR be a
7612 TARGET_EXPR below since otherwise the INIT_EXPR will
7613 attempt to make a bitwise copy of EXPR to initialize
7615 if (TREE_CODE (expr) != TARGET_EXPR)
7616 expr = get_target_expr (expr);
7617 /* Create the INIT_EXPR that will initialize the temporary
7619 init = build2 (INIT_EXPR, type, var, expr);
7620 if (at_function_scope_p ())
7622 add_decl_expr (var);
7624 if (TREE_STATIC (var))
7625 init = add_stmt_to_compound (init, register_dtor_fn (var));
7627 *cleanup = cxx_maybe_build_cleanup (var);
7629 /* We must be careful to destroy the temporary only
7630 after its initialization has taken place. If the
7631 initialization throws an exception, then the
7632 destructor should not be run. We cannot simply
7633 transform INIT into something like:
7635 (INIT, ({ CLEANUP_STMT; }))
7637 because emit_local_var always treats the
7638 initializer as a full-expression. Thus, the
7639 destructor would run too early; it would run at the
7640 end of initializing the reference variable, rather
7641 than at the end of the block enclosing the
7644 The solution is to pass back a cleanup expression
7645 which the caller is responsible for attaching to
7646 the statement tree. */
7650 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7651 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7652 static_aggregates = tree_cons (NULL_TREE, var,
7660 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7661 initializing a variable of that TYPE. If DECL is non-NULL, it is
7662 the VAR_DECL being initialized with the EXPR. (In that case, the
7663 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7664 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7665 return, if *CLEANUP is no longer NULL, it will be an expression
7666 that should be pushed as a cleanup after the returned expression
7667 is used to initialize DECL.
7669 Return the converted expression. */
7672 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
7673 tsubst_flags_t complain)
7678 if (type == error_mark_node || error_operand_p (expr))
7679 return error_mark_node;
7681 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7682 p = conversion_obstack_alloc (0);
7684 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7686 if (!conv || conv->bad_p)
7688 if (complain & tf_error)
7690 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7691 && !TYPE_REF_IS_RVALUE (type)
7692 && !real_lvalue_p (expr))
7693 error ("invalid initialization of non-const reference of "
7694 "type %qT from an rvalue of type %qT",
7695 type, TREE_TYPE (expr));
7697 error ("invalid initialization of reference of type "
7698 "%qT from expression of type %qT", type,
7701 return error_mark_node;
7704 /* If DECL is non-NULL, then this special rule applies:
7708 The temporary to which the reference is bound or the temporary
7709 that is the complete object to which the reference is bound
7710 persists for the lifetime of the reference.
7712 The temporaries created during the evaluation of the expression
7713 initializing the reference, except the temporary to which the
7714 reference is bound, are destroyed at the end of the
7715 full-expression in which they are created.
7717 In that case, we store the converted expression into a new
7718 VAR_DECL in a new scope.
7720 However, we want to be careful not to create temporaries when
7721 they are not required. For example, given:
7724 struct D : public B {};
7728 there is no need to copy the return value from "f"; we can just
7729 extend its lifetime. Similarly, given:
7732 struct T { operator S(); };
7736 we can extend the lifetime of the return value of the conversion
7738 gcc_assert (conv->kind == ck_ref_bind);
7742 tree base_conv_type;
7744 /* Skip over the REF_BIND. */
7745 conv = conv->u.next;
7746 /* If the next conversion is a BASE_CONV, skip that too -- but
7747 remember that the conversion was required. */
7748 if (conv->kind == ck_base)
7750 base_conv_type = conv->type;
7751 conv = conv->u.next;
7754 base_conv_type = NULL_TREE;
7755 /* Perform the remainder of the conversion. */
7756 expr = convert_like_real (conv, expr,
7757 /*fn=*/NULL_TREE, /*argnum=*/0,
7759 /*issue_conversion_warnings=*/true,
7761 tf_warning_or_error);
7762 if (error_operand_p (expr))
7763 expr = error_mark_node;
7766 if (!lvalue_or_rvalue_with_address_p (expr))
7769 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7770 /* Use its address to initialize the reference variable. */
7771 expr = build_address (var);
7773 expr = convert_to_base (expr,
7774 build_pointer_type (base_conv_type),
7775 /*check_access=*/true,
7777 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7780 /* Take the address of EXPR. */
7781 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7782 /* If a BASE_CONV was required, perform it now. */
7784 expr = (perform_implicit_conversion
7785 (build_pointer_type (base_conv_type), expr,
7786 tf_warning_or_error));
7787 expr = build_nop (type, expr);
7791 /* Perform the conversion. */
7792 expr = convert_like (conv, expr, tf_warning_or_error);
7794 /* Free all the conversions we allocated. */
7795 obstack_free (&conversion_obstack, p);
7800 /* Returns true iff TYPE is some variant of std::initializer_list. */
7803 is_std_init_list (tree type)
7805 return (CLASS_TYPE_P (type)
7806 && CP_TYPE_CONTEXT (type) == std_node
7807 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7810 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7811 will accept an argument list of a single std::initializer_list<T>. */
7814 is_list_ctor (tree decl)
7816 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7819 if (!args || args == void_list_node)
7822 arg = non_reference (TREE_VALUE (args));
7823 if (!is_std_init_list (arg))
7826 args = TREE_CHAIN (args);
7828 if (args && args != void_list_node && !TREE_PURPOSE (args))
7829 /* There are more non-defaulted parms. */
7835 #include "gt-cp-call.h"