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);
2461 int skip_without_in_chrg;
2462 tree first_arg_without_in_chrg;
2463 tree *args_without_in_chrg;
2464 unsigned int nargs_without_in_chrg;
2465 unsigned int ia, ix;
2467 struct z_candidate *cand;
2471 nargs = (first_arg == NULL_TREE ? 0 : 1) + VEC_length (tree, arglist);
2473 skip_without_in_chrg = 0;
2475 first_arg_without_in_chrg = first_arg;
2477 /* We don't do deduction on the in-charge parameter, the VTT
2478 parameter or 'this'. */
2479 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2481 if (first_arg_without_in_chrg != NULL_TREE)
2482 first_arg_without_in_chrg = NULL_TREE;
2484 ++skip_without_in_chrg;
2487 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2488 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2489 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2491 if (first_arg_without_in_chrg != NULL_TREE)
2492 first_arg_without_in_chrg = NULL_TREE;
2494 ++skip_without_in_chrg;
2497 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2498 + (VEC_length (tree, arglist)
2499 - skip_without_in_chrg));
2500 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2502 if (first_arg_without_in_chrg != NULL_TREE)
2504 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2507 for (ix = skip_without_in_chrg;
2508 VEC_iterate (tree, arglist, ix, arg);
2511 args_without_in_chrg[ia] = arg;
2514 gcc_assert (ia == nargs_without_in_chrg);
2516 i = fn_type_unification (tmpl, explicit_targs, targs,
2517 args_without_in_chrg,
2518 nargs_without_in_chrg,
2519 return_type, strict, flags);
2524 fn = instantiate_template (tmpl, targs, tf_none);
2525 if (fn == error_mark_node)
2530 A member function template is never instantiated to perform the
2531 copy of a class object to an object of its class type.
2533 It's a little unclear what this means; the standard explicitly
2534 does allow a template to be used to copy a class. For example,
2539 template <class T> A(const T&);
2542 void g () { A a (f ()); }
2544 the member template will be used to make the copy. The section
2545 quoted above appears in the paragraph that forbids constructors
2546 whose only parameter is (a possibly cv-qualified variant of) the
2547 class type, and a logical interpretation is that the intent was
2548 to forbid the instantiation of member templates which would then
2550 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2552 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2553 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2558 if (obj != NULL_TREE)
2559 /* Aha, this is a conversion function. */
2560 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2561 access_path, conversion_path);
2563 cand = add_function_candidate (candidates, fn, ctype,
2564 first_arg, arglist, access_path,
2565 conversion_path, flags);
2566 if (DECL_TI_TEMPLATE (fn) != tmpl)
2567 /* This situation can occur if a member template of a template
2568 class is specialized. Then, instantiate_template might return
2569 an instantiation of the specialization, in which case the
2570 DECL_TI_TEMPLATE field will point at the original
2571 specialization. For example:
2573 template <class T> struct S { template <class U> void f(U);
2574 template <> void f(int) {}; };
2578 Here, TMPL will be template <class U> S<double>::f(U).
2579 And, instantiate template will give us the specialization
2580 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2581 for this will point at template <class T> template <> S<T>::f(int),
2582 so that we can find the definition. For the purposes of
2583 overload resolution, however, we want the original TMPL. */
2584 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2586 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2592 static struct z_candidate *
2593 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2594 tree explicit_targs, tree first_arg,
2595 const VEC(tree,gc) *arglist, tree return_type,
2596 tree access_path, tree conversion_path, int flags,
2597 unification_kind_t strict)
2600 add_template_candidate_real (candidates, tmpl, ctype,
2601 explicit_targs, first_arg, arglist,
2602 return_type, access_path, conversion_path,
2603 flags, NULL_TREE, strict);
2607 static struct z_candidate *
2608 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2609 tree obj, tree first_arg,
2610 const VEC(tree,gc) *arglist,
2611 tree return_type, tree access_path,
2612 tree conversion_path)
2615 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2616 first_arg, arglist, return_type, access_path,
2617 conversion_path, 0, obj, DEDUCE_CONV);
2620 /* The CANDS are the set of candidates that were considered for
2621 overload resolution. Return the set of viable candidates. If none
2622 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2623 is true if a candidate should be considered viable only if it is
2626 static struct z_candidate*
2627 splice_viable (struct z_candidate *cands,
2631 struct z_candidate *viable;
2632 struct z_candidate **last_viable;
2633 struct z_candidate **cand;
2636 last_viable = &viable;
2637 *any_viable_p = false;
2642 struct z_candidate *c = *cand;
2643 if (strict_p ? c->viable == 1 : c->viable)
2648 last_viable = &c->next;
2649 *any_viable_p = true;
2655 return viable ? viable : cands;
2659 any_strictly_viable (struct z_candidate *cands)
2661 for (; cands; cands = cands->next)
2662 if (cands->viable == 1)
2667 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2668 words, it is about to become the "this" pointer for a member
2669 function call. Take the address of the object. */
2672 build_this (tree obj)
2674 /* In a template, we are only concerned about the type of the
2675 expression, so we can take a shortcut. */
2676 if (processing_template_decl)
2677 return build_address (obj);
2679 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2682 /* Returns true iff functions are equivalent. Equivalent functions are
2683 not '==' only if one is a function-local extern function or if
2684 both are extern "C". */
2687 equal_functions (tree fn1, tree fn2)
2689 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2690 || DECL_EXTERN_C_FUNCTION_P (fn1))
2691 return decls_match (fn1, fn2);
2695 /* Print information about one overload candidate CANDIDATE. MSGSTR
2696 is the text to print before the candidate itself.
2698 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2699 to have been run through gettext by the caller. This wart makes
2700 life simpler in print_z_candidates and for the translators. */
2703 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2705 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2707 if (candidate->num_convs == 3)
2708 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2709 candidate->convs[0]->type,
2710 candidate->convs[1]->type,
2711 candidate->convs[2]->type);
2712 else if (candidate->num_convs == 2)
2713 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2714 candidate->convs[0]->type,
2715 candidate->convs[1]->type);
2717 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2718 candidate->convs[0]->type);
2720 else if (TYPE_P (candidate->fn))
2721 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2722 else if (candidate->viable == -1)
2723 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2724 else if (DECL_DELETED_FN (candidate->fn))
2725 inform (input_location, "%s %+#D <deleted>", msgstr, candidate->fn);
2727 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2731 print_z_candidates (struct z_candidate *candidates)
2734 struct z_candidate *cand1;
2735 struct z_candidate **cand2;
2740 /* Remove deleted candidates. */
2742 for (cand2 = &cand1; *cand2; )
2744 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2745 && DECL_DELETED_FN ((*cand2)->fn))
2746 *cand2 = (*cand2)->next;
2748 cand2 = &(*cand2)->next;
2750 /* ...if there are any non-deleted ones. */
2754 /* There may be duplicates in the set of candidates. We put off
2755 checking this condition as long as possible, since we have no way
2756 to eliminate duplicates from a set of functions in less than n^2
2757 time. Now we are about to emit an error message, so it is more
2758 permissible to go slowly. */
2759 for (cand1 = candidates; cand1; cand1 = cand1->next)
2761 tree fn = cand1->fn;
2762 /* Skip builtin candidates and conversion functions. */
2763 if (TREE_CODE (fn) != FUNCTION_DECL)
2765 cand2 = &cand1->next;
2768 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2769 && equal_functions (fn, (*cand2)->fn))
2770 *cand2 = (*cand2)->next;
2772 cand2 = &(*cand2)->next;
2776 str = _("candidates are:");
2777 print_z_candidate (str, candidates);
2778 if (candidates->next)
2780 /* Indent successive candidates by the width of the translation
2781 of the above string. */
2782 size_t len = gcc_gettext_width (str) + 1;
2783 char *spaces = (char *) alloca (len);
2784 memset (spaces, ' ', len-1);
2785 spaces[len - 1] = '\0';
2787 candidates = candidates->next;
2790 print_z_candidate (spaces, candidates);
2791 candidates = candidates->next;
2797 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2798 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2799 the result of the conversion function to convert it to the final
2800 desired type. Merge the two sequences into a single sequence,
2801 and return the merged sequence. */
2804 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2808 gcc_assert (user_seq->kind == ck_user);
2810 /* Find the end of the second conversion sequence. */
2812 while ((*t)->kind != ck_identity)
2813 t = &((*t)->u.next);
2815 /* Replace the identity conversion with the user conversion
2819 /* The entire sequence is a user-conversion sequence. */
2820 std_seq->user_conv_p = true;
2825 /* Returns the best overload candidate to perform the requested
2826 conversion. This function is used for three the overloading situations
2827 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2828 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2829 per [dcl.init.ref], so we ignore temporary bindings. */
2831 static struct z_candidate *
2832 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2834 struct z_candidate *candidates, *cand;
2835 tree fromtype = TREE_TYPE (expr);
2836 tree ctors = NULL_TREE;
2837 tree conv_fns = NULL_TREE;
2838 conversion *conv = NULL;
2839 tree first_arg = NULL_TREE;
2840 VEC(tree,gc) *args = NULL;
2844 /* We represent conversion within a hierarchy using RVALUE_CONV and
2845 BASE_CONV, as specified by [over.best.ics]; these become plain
2846 constructor calls, as specified in [dcl.init]. */
2847 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2848 || !DERIVED_FROM_P (totype, fromtype));
2850 if (MAYBE_CLASS_TYPE_P (totype))
2851 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2853 if (MAYBE_CLASS_TYPE_P (fromtype))
2855 tree to_nonref = non_reference (totype);
2856 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2857 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2858 && DERIVED_FROM_P (to_nonref, fromtype)))
2860 /* [class.conv.fct] A conversion function is never used to
2861 convert a (possibly cv-qualified) object to the (possibly
2862 cv-qualified) same object type (or a reference to it), to a
2863 (possibly cv-qualified) base class of that type (or a
2864 reference to it)... */
2867 conv_fns = lookup_conversions (fromtype);
2871 flags |= LOOKUP_NO_CONVERSION;
2873 /* It's OK to bind a temporary for converting constructor arguments, but
2874 not in converting the return value of a conversion operator. */
2875 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2876 flags &= ~LOOKUP_NO_TEMP_BIND;
2880 ctors = BASELINK_FUNCTIONS (ctors);
2882 first_arg = build_int_cst (build_pointer_type (totype), 0);
2883 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2884 && !TYPE_HAS_LIST_CTOR (totype))
2886 args = ctor_to_vec (expr);
2887 /* We still allow more conversions within an init-list. */
2888 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2889 /* But not for the copy ctor. */
2890 |LOOKUP_NO_COPY_CTOR_CONVERSION
2891 |LOOKUP_NO_NARROWING);
2894 args = make_tree_vector_single (expr);
2896 /* We should never try to call the abstract or base constructor
2898 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2899 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2901 for (; ctors; ctors = OVL_NEXT (ctors))
2903 tree ctor = OVL_CURRENT (ctors);
2904 if (DECL_NONCONVERTING_P (ctor)
2905 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2908 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2909 cand = add_template_candidate (&candidates, ctor, totype,
2910 NULL_TREE, first_arg, args, NULL_TREE,
2911 TYPE_BINFO (totype),
2912 TYPE_BINFO (totype),
2916 cand = add_function_candidate (&candidates, ctor, totype,
2917 first_arg, args, TYPE_BINFO (totype),
2918 TYPE_BINFO (totype),
2923 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2925 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2926 set, then this is copy-initialization. In that case, "The
2927 result of the call is then used to direct-initialize the
2928 object that is the destination of the copy-initialization."
2931 We represent this in the conversion sequence with an
2932 rvalue conversion, which means a constructor call. */
2933 if (TREE_CODE (totype) != REFERENCE_TYPE
2934 && !(convflags & LOOKUP_NO_TEMP_BIND))
2936 = build_conv (ck_rvalue, totype, cand->second_conv);
2941 first_arg = build_this (expr);
2943 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2946 tree conversion_path = TREE_PURPOSE (conv_fns);
2948 /* If we are called to convert to a reference type, we are trying to
2949 find an lvalue binding, so don't even consider temporaries. If
2950 we don't find an lvalue binding, the caller will try again to
2951 look for a temporary binding. */
2952 if (TREE_CODE (totype) == REFERENCE_TYPE)
2953 convflags |= LOOKUP_NO_TEMP_BIND;
2955 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2957 tree fn = OVL_CURRENT (fns);
2958 tree first = first_arg;
2960 if (DECL_NONCONVERTING_P (fn)
2961 && (flags & LOOKUP_ONLYCONVERTING))
2964 /* Lambdas have a static conversion op. */
2965 if (DECL_STATIC_FUNCTION_P (fn))
2968 /* [over.match.funcs] For conversion functions, the function
2969 is considered to be a member of the class of the implicit
2970 object argument for the purpose of defining the type of
2971 the implicit object parameter.
2973 So we pass fromtype as CTYPE to add_*_candidate. */
2975 if (TREE_CODE (fn) == TEMPLATE_DECL)
2976 cand = add_template_candidate (&candidates, fn, fromtype,
2978 first, NULL, totype,
2979 TYPE_BINFO (fromtype),
2984 cand = add_function_candidate (&candidates, fn, fromtype,
2986 TYPE_BINFO (fromtype),
2993 = implicit_conversion (totype,
2994 TREE_TYPE (TREE_TYPE (cand->fn)),
2996 /*c_cast_p=*/false, convflags);
2998 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2999 copy-initialization. In that case, "The result of the
3000 call is then used to direct-initialize the object that is
3001 the destination of the copy-initialization." [dcl.init]
3003 We represent this in the conversion sequence with an
3004 rvalue conversion, which means a constructor call. But
3005 don't add a second rvalue conversion if there's already
3006 one there. Which there really shouldn't be, but it's
3007 harmless since we'd add it here anyway. */
3008 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3009 && !(convflags & LOOKUP_NO_TEMP_BIND))
3010 ics = build_conv (ck_rvalue, totype, ics);
3012 cand->second_conv = ics;
3016 else if (candidates->viable == 1 && ics->bad_p)
3022 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3026 cand = tourney (candidates);
3029 if (flags & LOOKUP_COMPLAIN)
3031 error ("conversion from %qT to %qT is ambiguous",
3033 print_z_candidates (candidates);
3036 cand = candidates; /* any one will do */
3037 cand->second_conv = build_ambiguous_conv (totype, expr);
3038 cand->second_conv->user_conv_p = true;
3039 if (!any_strictly_viable (candidates))
3040 cand->second_conv->bad_p = true;
3041 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3042 ambiguous conversion is no worse than another user-defined
3048 /* Build the user conversion sequence. */
3051 (DECL_CONSTRUCTOR_P (cand->fn)
3052 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3053 build_identity_conv (TREE_TYPE (expr), expr));
3056 /* Remember that this was a list-initialization. */
3057 if (flags & LOOKUP_NO_NARROWING)
3058 conv->check_narrowing = true;
3060 /* Combine it with the second conversion sequence. */
3061 cand->second_conv = merge_conversion_sequences (conv,
3064 if (cand->viable == -1)
3065 cand->second_conv->bad_p = true;
3071 build_user_type_conversion (tree totype, tree expr, int flags)
3073 struct z_candidate *cand
3074 = build_user_type_conversion_1 (totype, expr, flags);
3078 if (cand->second_conv->kind == ck_ambig)
3079 return error_mark_node;
3080 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3081 return convert_from_reference (expr);
3086 /* Do any initial processing on the arguments to a function call. */
3088 static VEC(tree,gc) *
3089 resolve_args (VEC(tree,gc) *args)
3094 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3096 if (error_operand_p (arg))
3098 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3100 error ("invalid use of void expression");
3103 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3109 /* Perform overload resolution on FN, which is called with the ARGS.
3111 Return the candidate function selected by overload resolution, or
3112 NULL if the event that overload resolution failed. In the case
3113 that overload resolution fails, *CANDIDATES will be the set of
3114 candidates considered, and ANY_VIABLE_P will be set to true or
3115 false to indicate whether or not any of the candidates were
3118 The ARGS should already have gone through RESOLVE_ARGS before this
3119 function is called. */
3121 static struct z_candidate *
3122 perform_overload_resolution (tree fn,
3123 const VEC(tree,gc) *args,
3124 struct z_candidate **candidates,
3127 struct z_candidate *cand;
3128 tree explicit_targs = NULL_TREE;
3129 int template_only = 0;
3132 *any_viable_p = true;
3135 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3136 || TREE_CODE (fn) == TEMPLATE_DECL
3137 || TREE_CODE (fn) == OVERLOAD
3138 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3140 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3142 explicit_targs = TREE_OPERAND (fn, 1);
3143 fn = TREE_OPERAND (fn, 0);
3147 /* Add the various candidate functions. */
3148 add_candidates (fn, args, explicit_targs, template_only,
3149 /*conversion_path=*/NULL_TREE,
3150 /*access_path=*/NULL_TREE,
3154 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3158 cand = tourney (*candidates);
3162 /* Return an expression for a call to FN (a namespace-scope function,
3163 or a static member function) with the ARGS. This may change
3167 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3168 tsubst_flags_t complain)
3170 struct z_candidate *candidates, *cand;
3175 if (args != NULL && *args != NULL)
3177 *args = resolve_args (*args);
3179 return error_mark_node;
3182 /* If this function was found without using argument dependent
3183 lookup, then we want to ignore any undeclared friend
3189 fn = remove_hidden_names (fn);
3192 if (complain & tf_error)
3193 error ("no matching function for call to %<%D(%A)%>",
3194 DECL_NAME (OVL_CURRENT (orig_fn)),
3195 build_tree_list_vec (*args));
3196 return error_mark_node;
3200 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3201 p = conversion_obstack_alloc (0);
3203 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3207 if (complain & tf_error)
3209 if (!any_viable_p && candidates && ! candidates->next)
3210 return cp_build_function_call_vec (candidates->fn, args, complain);
3211 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3212 fn = TREE_OPERAND (fn, 0);
3214 error ("no matching function for call to %<%D(%A)%>",
3215 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3217 error ("call of overloaded %<%D(%A)%> is ambiguous",
3218 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3220 print_z_candidates (candidates);
3222 result = error_mark_node;
3225 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3227 /* Free all the conversions we allocated. */
3228 obstack_free (&conversion_obstack, p);
3233 /* Build a call to a global operator new. FNNAME is the name of the
3234 operator (either "operator new" or "operator new[]") and ARGS are
3235 the arguments provided. This may change ARGS. *SIZE points to the
3236 total number of bytes required by the allocation, and is updated if
3237 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3238 be used. If this function determines that no cookie should be
3239 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3240 non-NULL, it will be set, upon return, to the allocation function
3244 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3245 tree *size, tree *cookie_size,
3249 struct z_candidate *candidates;
3250 struct z_candidate *cand;
3255 VEC_safe_insert (tree, gc, *args, 0, *size);
3256 *args = resolve_args (*args);
3258 return error_mark_node;
3264 If this lookup fails to find the name, or if the allocated type
3265 is not a class type, the allocation function's name is looked
3266 up in the global scope.
3268 we disregard block-scope declarations of "operator new". */
3269 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3271 /* Figure out what function is being called. */
3272 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3274 /* If no suitable function could be found, issue an error message
3279 error ("no matching function for call to %<%D(%A)%>",
3280 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3282 error ("call of overloaded %<%D(%A)%> is ambiguous",
3283 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3285 print_z_candidates (candidates);
3286 return error_mark_node;
3289 /* If a cookie is required, add some extra space. Whether
3290 or not a cookie is required cannot be determined until
3291 after we know which function was called. */
3294 bool use_cookie = true;
3295 if (!abi_version_at_least (2))
3297 /* In G++ 3.2, the check was implemented incorrectly; it
3298 looked at the placement expression, rather than the
3299 type of the function. */
3300 if (VEC_length (tree, *args) == 2
3301 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3309 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3310 /* Skip the size_t parameter. */
3311 arg_types = TREE_CHAIN (arg_types);
3312 /* Check the remaining parameters (if any). */
3314 && TREE_CHAIN (arg_types) == void_list_node
3315 && same_type_p (TREE_VALUE (arg_types),
3319 /* If we need a cookie, adjust the number of bytes allocated. */
3322 /* Update the total size. */
3323 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3324 /* Update the argument list to reflect the adjusted size. */
3325 VEC_replace (tree, *args, 0, *size);
3328 *cookie_size = NULL_TREE;
3331 /* Tell our caller which function we decided to call. */
3335 /* Build the CALL_EXPR. */
3336 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3339 /* Build a new call to operator(). This may change ARGS. */
3342 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3344 struct z_candidate *candidates = 0, *cand;
3345 tree fns, convs, first_mem_arg = NULL_TREE;
3346 tree type = TREE_TYPE (obj);
3348 tree result = NULL_TREE;
3351 if (error_operand_p (obj))
3352 return error_mark_node;
3354 obj = prep_operand (obj);
3356 if (TYPE_PTRMEMFUNC_P (type))
3358 if (complain & tf_error)
3359 /* It's no good looking for an overloaded operator() on a
3360 pointer-to-member-function. */
3361 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3362 return error_mark_node;
3365 if (TYPE_BINFO (type))
3367 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3368 if (fns == error_mark_node)
3369 return error_mark_node;
3374 if (args != NULL && *args != NULL)
3376 *args = resolve_args (*args);
3378 return error_mark_node;
3381 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3382 p = conversion_obstack_alloc (0);
3386 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3387 first_mem_arg = build_this (obj);
3389 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3391 tree fn = OVL_CURRENT (fns);
3393 tree lfirst = first_mem_arg;
3394 if (DECL_STATIC_FUNCTION_P (fn))
3397 if (TREE_CODE (fn) == TEMPLATE_DECL)
3398 add_template_candidate (&candidates, fn, base, NULL_TREE,
3399 lfirst, *args, NULL_TREE,
3402 LOOKUP_NORMAL, DEDUCE_CALL);
3404 add_function_candidate
3405 (&candidates, fn, base, lfirst, *args, TYPE_BINFO (type),
3406 TYPE_BINFO (type), LOOKUP_NORMAL);
3410 /* Rather than mess with handling static conversion ops here, just don't
3411 look at conversions in lambdas. */
3412 if (LAMBDA_TYPE_P (type))
3415 convs = lookup_conversions (type);
3417 for (; convs; convs = TREE_CHAIN (convs))
3419 tree fns = TREE_VALUE (convs);
3420 tree totype = TREE_TYPE (convs);
3422 if ((TREE_CODE (totype) == POINTER_TYPE
3423 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3424 || (TREE_CODE (totype) == REFERENCE_TYPE
3425 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3426 || (TREE_CODE (totype) == REFERENCE_TYPE
3427 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3428 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3429 for (; fns; fns = OVL_NEXT (fns))
3431 tree fn = OVL_CURRENT (fns);
3433 if (DECL_NONCONVERTING_P (fn))
3436 if (TREE_CODE (fn) == TEMPLATE_DECL)
3437 add_template_conv_candidate
3438 (&candidates, fn, obj, NULL_TREE, *args, totype,
3439 /*access_path=*/NULL_TREE,
3440 /*conversion_path=*/NULL_TREE);
3442 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3443 *args, /*conversion_path=*/NULL_TREE,
3444 /*access_path=*/NULL_TREE);
3448 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3451 if (complain & tf_error)
3453 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3454 build_tree_list_vec (*args));
3455 print_z_candidates (candidates);
3457 result = error_mark_node;
3461 cand = tourney (candidates);
3464 if (complain & tf_error)
3466 error ("call of %<(%T) (%A)%> is ambiguous",
3467 TREE_TYPE (obj), build_tree_list_vec (*args));
3468 print_z_candidates (candidates);
3470 result = error_mark_node;
3472 /* Since cand->fn will be a type, not a function, for a conversion
3473 function, we must be careful not to unconditionally look at
3475 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3476 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3477 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3480 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3482 obj = convert_from_reference (obj);
3483 result = cp_build_function_call_vec (obj, args, complain);
3487 /* Free all the conversions we allocated. */
3488 obstack_free (&conversion_obstack, p);
3494 op_error (enum tree_code code, enum tree_code code2,
3495 tree arg1, tree arg2, tree arg3, const char *problem)
3499 if (code == MODIFY_EXPR)
3500 opname = assignment_operator_name_info[code2].name;
3502 opname = operator_name_info[code].name;
3507 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3508 problem, arg1, arg2, arg3);
3511 case POSTINCREMENT_EXPR:
3512 case POSTDECREMENT_EXPR:
3513 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3517 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3522 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3527 error ("%s for %<operator%s%> in %<%E %s %E%>",
3528 problem, opname, arg1, opname, arg2);
3530 error ("%s for %<operator%s%> in %<%s%E%>",
3531 problem, opname, opname, arg1);
3536 /* Return the implicit conversion sequence that could be used to
3537 convert E1 to E2 in [expr.cond]. */
3540 conditional_conversion (tree e1, tree e2)
3542 tree t1 = non_reference (TREE_TYPE (e1));
3543 tree t2 = non_reference (TREE_TYPE (e2));
3549 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3550 implicitly converted (clause _conv_) to the type "reference to
3551 T2", subject to the constraint that in the conversion the
3552 reference must bind directly (_dcl.init.ref_) to E1. */
3553 if (real_lvalue_p (e2))
3555 conv = implicit_conversion (build_reference_type (t2),
3559 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3566 If E1 and E2 have class type, and the underlying class types are
3567 the same or one is a base class of the other: E1 can be converted
3568 to match E2 if the class of T2 is the same type as, or a base
3569 class of, the class of T1, and the cv-qualification of T2 is the
3570 same cv-qualification as, or a greater cv-qualification than, the
3571 cv-qualification of T1. If the conversion is applied, E1 is
3572 changed to an rvalue of type T2 that still refers to the original
3573 source class object (or the appropriate subobject thereof). */
3574 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3575 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3577 if (good_base && at_least_as_qualified_p (t2, t1))
3579 conv = build_identity_conv (t1, e1);
3580 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3581 TYPE_MAIN_VARIANT (t2)))
3582 conv = build_conv (ck_base, t2, conv);
3584 conv = build_conv (ck_rvalue, t2, conv);
3593 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3594 converted to the type that expression E2 would have if E2 were
3595 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3596 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3600 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3601 arguments to the conditional expression. */
3604 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3605 tsubst_flags_t complain)
3609 tree result = NULL_TREE;
3611 tree result_type = NULL_TREE;
3612 bool lvalue_p = true;
3613 struct z_candidate *candidates = 0;
3614 struct z_candidate *cand;
3617 /* As a G++ extension, the second argument to the conditional can be
3618 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3619 c'.) If the second operand is omitted, make sure it is
3620 calculated only once. */
3623 if (complain & tf_error)
3624 pedwarn (input_location, OPT_pedantic,
3625 "ISO C++ forbids omitting the middle term of a ?: expression");
3627 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3628 if (real_lvalue_p (arg1))
3629 arg2 = arg1 = stabilize_reference (arg1);
3631 arg2 = arg1 = save_expr (arg1);
3636 The first expression is implicitly converted to bool (clause
3638 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
3641 /* If something has already gone wrong, just pass that fact up the
3643 if (error_operand_p (arg1)
3644 || error_operand_p (arg2)
3645 || error_operand_p (arg3))
3646 return error_mark_node;
3650 If either the second or the third operand has type (possibly
3651 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3652 array-to-pointer (_conv.array_), and function-to-pointer
3653 (_conv.func_) standard conversions are performed on the second
3654 and third operands. */
3655 arg2_type = unlowered_expr_type (arg2);
3656 arg3_type = unlowered_expr_type (arg3);
3657 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3659 /* Do the conversions. We don't these for `void' type arguments
3660 since it can't have any effect and since decay_conversion
3661 does not handle that case gracefully. */
3662 if (!VOID_TYPE_P (arg2_type))
3663 arg2 = decay_conversion (arg2);
3664 if (!VOID_TYPE_P (arg3_type))
3665 arg3 = decay_conversion (arg3);
3666 arg2_type = TREE_TYPE (arg2);
3667 arg3_type = TREE_TYPE (arg3);
3671 One of the following shall hold:
3673 --The second or the third operand (but not both) is a
3674 throw-expression (_except.throw_); the result is of the
3675 type of the other and is an rvalue.
3677 --Both the second and the third operands have type void; the
3678 result is of type void and is an rvalue.
3680 We must avoid calling force_rvalue for expressions of type
3681 "void" because it will complain that their value is being
3683 if (TREE_CODE (arg2) == THROW_EXPR
3684 && TREE_CODE (arg3) != THROW_EXPR)
3686 if (!VOID_TYPE_P (arg3_type))
3687 arg3 = force_rvalue (arg3);
3688 arg3_type = TREE_TYPE (arg3);
3689 result_type = arg3_type;
3691 else if (TREE_CODE (arg2) != THROW_EXPR
3692 && TREE_CODE (arg3) == THROW_EXPR)
3694 if (!VOID_TYPE_P (arg2_type))
3695 arg2 = force_rvalue (arg2);
3696 arg2_type = TREE_TYPE (arg2);
3697 result_type = arg2_type;
3699 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3700 result_type = void_type_node;
3703 if (complain & tf_error)
3705 if (VOID_TYPE_P (arg2_type))
3706 error ("second operand to the conditional operator "
3707 "is of type %<void%>, "
3708 "but the third operand is neither a throw-expression "
3709 "nor of type %<void%>");
3711 error ("third operand to the conditional operator "
3712 "is of type %<void%>, "
3713 "but the second operand is neither a throw-expression "
3714 "nor of type %<void%>");
3716 return error_mark_node;
3720 goto valid_operands;
3724 Otherwise, if the second and third operand have different types,
3725 and either has (possibly cv-qualified) class type, an attempt is
3726 made to convert each of those operands to the type of the other. */
3727 else if (!same_type_p (arg2_type, arg3_type)
3728 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3733 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3734 p = conversion_obstack_alloc (0);
3736 conv2 = conditional_conversion (arg2, arg3);
3737 conv3 = conditional_conversion (arg3, arg2);
3741 If both can be converted, or one can be converted but the
3742 conversion is ambiguous, the program is ill-formed. If
3743 neither can be converted, the operands are left unchanged and
3744 further checking is performed as described below. If exactly
3745 one conversion is possible, that conversion is applied to the
3746 chosen operand and the converted operand is used in place of
3747 the original operand for the remainder of this section. */
3748 if ((conv2 && !conv2->bad_p
3749 && conv3 && !conv3->bad_p)
3750 || (conv2 && conv2->kind == ck_ambig)
3751 || (conv3 && conv3->kind == ck_ambig))
3753 error ("operands to ?: have different types %qT and %qT",
3754 arg2_type, arg3_type);
3755 result = error_mark_node;
3757 else if (conv2 && (!conv2->bad_p || !conv3))
3759 arg2 = convert_like (conv2, arg2, complain);
3760 arg2 = convert_from_reference (arg2);
3761 arg2_type = TREE_TYPE (arg2);
3762 /* Even if CONV2 is a valid conversion, the result of the
3763 conversion may be invalid. For example, if ARG3 has type
3764 "volatile X", and X does not have a copy constructor
3765 accepting a "volatile X&", then even if ARG2 can be
3766 converted to X, the conversion will fail. */
3767 if (error_operand_p (arg2))
3768 result = error_mark_node;
3770 else if (conv3 && (!conv3->bad_p || !conv2))
3772 arg3 = convert_like (conv3, arg3, complain);
3773 arg3 = convert_from_reference (arg3);
3774 arg3_type = TREE_TYPE (arg3);
3775 if (error_operand_p (arg3))
3776 result = error_mark_node;
3779 /* Free all the conversions we allocated. */
3780 obstack_free (&conversion_obstack, p);
3785 /* If, after the conversion, both operands have class type,
3786 treat the cv-qualification of both operands as if it were the
3787 union of the cv-qualification of the operands.
3789 The standard is not clear about what to do in this
3790 circumstance. For example, if the first operand has type
3791 "const X" and the second operand has a user-defined
3792 conversion to "volatile X", what is the type of the second
3793 operand after this step? Making it be "const X" (matching
3794 the first operand) seems wrong, as that discards the
3795 qualification without actually performing a copy. Leaving it
3796 as "volatile X" seems wrong as that will result in the
3797 conditional expression failing altogether, even though,
3798 according to this step, the one operand could be converted to
3799 the type of the other. */
3800 if ((conv2 || conv3)
3801 && CLASS_TYPE_P (arg2_type)
3802 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3803 arg2_type = arg3_type =
3804 cp_build_qualified_type (arg2_type,
3805 TYPE_QUALS (arg2_type)
3806 | TYPE_QUALS (arg3_type));
3811 If the second and third operands are lvalues and have the same
3812 type, the result is of that type and is an lvalue. */
3813 if (real_lvalue_p (arg2)
3814 && real_lvalue_p (arg3)
3815 && same_type_p (arg2_type, arg3_type))
3817 result_type = arg2_type;
3818 goto valid_operands;
3823 Otherwise, the result is an rvalue. If the second and third
3824 operand do not have the same type, and either has (possibly
3825 cv-qualified) class type, overload resolution is used to
3826 determine the conversions (if any) to be applied to the operands
3827 (_over.match.oper_, _over.built_). */
3829 if (!same_type_p (arg2_type, arg3_type)
3830 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3836 /* Rearrange the arguments so that add_builtin_candidate only has
3837 to know about two args. In build_builtin_candidate, the
3838 arguments are unscrambled. */
3842 add_builtin_candidates (&candidates,
3845 ansi_opname (COND_EXPR),
3851 If the overload resolution fails, the program is
3853 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3856 if (complain & tf_error)
3858 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3859 print_z_candidates (candidates);
3861 return error_mark_node;
3863 cand = tourney (candidates);
3866 if (complain & tf_error)
3868 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3869 print_z_candidates (candidates);
3871 return error_mark_node;
3876 Otherwise, the conversions thus determined are applied, and
3877 the converted operands are used in place of the original
3878 operands for the remainder of this section. */
3879 conv = cand->convs[0];
3880 arg1 = convert_like (conv, arg1, complain);
3881 conv = cand->convs[1];
3882 arg2 = convert_like (conv, arg2, complain);
3883 arg2_type = TREE_TYPE (arg2);
3884 conv = cand->convs[2];
3885 arg3 = convert_like (conv, arg3, complain);
3886 arg3_type = TREE_TYPE (arg3);
3891 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3892 and function-to-pointer (_conv.func_) standard conversions are
3893 performed on the second and third operands.
3895 We need to force the lvalue-to-rvalue conversion here for class types,
3896 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3897 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3900 arg2 = force_rvalue (arg2);
3901 if (!CLASS_TYPE_P (arg2_type))
3902 arg2_type = TREE_TYPE (arg2);
3904 arg3 = force_rvalue (arg3);
3905 if (!CLASS_TYPE_P (arg3_type))
3906 arg3_type = TREE_TYPE (arg3);
3908 if (arg2 == error_mark_node || arg3 == error_mark_node)
3909 return error_mark_node;
3913 After those conversions, one of the following shall hold:
3915 --The second and third operands have the same type; the result is of
3917 if (same_type_p (arg2_type, arg3_type))
3918 result_type = arg2_type;
3921 --The second and third operands have arithmetic or enumeration
3922 type; the usual arithmetic conversions are performed to bring
3923 them to a common type, and the result is of that type. */
3924 else if ((ARITHMETIC_TYPE_P (arg2_type)
3925 || UNSCOPED_ENUM_P (arg2_type))
3926 && (ARITHMETIC_TYPE_P (arg3_type)
3927 || UNSCOPED_ENUM_P (arg3_type)))
3929 /* In this case, there is always a common type. */
3930 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3933 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3934 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3936 if (complain & tf_warning)
3938 "enumeral mismatch in conditional expression: %qT vs %qT",
3939 arg2_type, arg3_type);
3941 else if (extra_warnings
3942 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3943 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3944 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3945 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3947 if (complain & tf_warning)
3949 "enumeral and non-enumeral type in conditional expression");
3952 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3953 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3957 --The second and third operands have pointer type, or one has
3958 pointer type and the other is a null pointer constant; pointer
3959 conversions (_conv.ptr_) and qualification conversions
3960 (_conv.qual_) are performed to bring them to their composite
3961 pointer type (_expr.rel_). The result is of the composite
3964 --The second and third operands have pointer to member type, or
3965 one has pointer to member type and the other is a null pointer
3966 constant; pointer to member conversions (_conv.mem_) and
3967 qualification conversions (_conv.qual_) are performed to bring
3968 them to a common type, whose cv-qualification shall match the
3969 cv-qualification of either the second or the third operand.
3970 The result is of the common type. */
3971 else if ((null_ptr_cst_p (arg2)
3972 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3973 || (null_ptr_cst_p (arg3)
3974 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3975 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3976 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3977 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3979 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3980 arg3, "conditional expression",
3982 if (result_type == error_mark_node)
3983 return error_mark_node;
3984 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3985 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3990 if (complain & tf_error)
3991 error ("operands to ?: have different types %qT and %qT",
3992 arg2_type, arg3_type);
3993 return error_mark_node;
3997 result_save = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
3998 result = fold_if_not_in_template (result_save);
4000 if (cp_unevaluated_operand && TREE_CODE (result) == CALL_EXPR)
4001 /* Avoid folding to a CALL_EXPR within decltype (c++/42013). */
4002 result = result_save;
4004 /* We can't use result_type below, as fold might have returned a
4009 /* Expand both sides into the same slot, hopefully the target of
4010 the ?: expression. We used to check for TARGET_EXPRs here,
4011 but now we sometimes wrap them in NOP_EXPRs so the test would
4013 if (CLASS_TYPE_P (TREE_TYPE (result)))
4014 result = get_target_expr (result);
4015 /* If this expression is an rvalue, but might be mistaken for an
4016 lvalue, we must add a NON_LVALUE_EXPR. */
4017 result = rvalue (result);
4023 /* OPERAND is an operand to an expression. Perform necessary steps
4024 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4028 prep_operand (tree operand)
4032 if (CLASS_TYPE_P (TREE_TYPE (operand))
4033 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4034 /* Make sure the template type is instantiated now. */
4035 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4041 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4042 OVERLOAD) to the CANDIDATES, returning an updated list of
4043 CANDIDATES. The ARGS are the arguments provided to the call,
4044 without any implicit object parameter. This may change ARGS. The
4045 EXPLICIT_TARGS are explicit template arguments provided.
4046 TEMPLATE_ONLY is true if only template functions should be
4047 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4048 add_function_candidate. */
4051 add_candidates (tree fns, const VEC(tree,gc) *args,
4052 tree explicit_targs, bool template_only,
4053 tree conversion_path, tree access_path,
4055 struct z_candidate **candidates)
4058 VEC(tree,gc) *non_static_args;
4061 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4062 /* Delay creating the implicit this parameter until it is needed. */
4063 non_static_args = NULL;
4064 first_arg = NULL_TREE;
4070 const VEC(tree,gc) *fn_args;
4072 fn = OVL_CURRENT (fns);
4073 /* Figure out which set of arguments to use. */
4074 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4076 /* If this function is a non-static member, prepend the implicit
4077 object parameter. */
4078 if (non_static_args == NULL)
4083 non_static_args = VEC_alloc (tree, gc,
4084 VEC_length (tree, args) - 1);
4085 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4086 VEC_quick_push (tree, non_static_args, arg);
4088 if (first_arg == NULL_TREE)
4089 first_arg = build_this (VEC_index (tree, args, 0));
4090 fn_first_arg = first_arg;
4091 fn_args = non_static_args;
4095 /* Otherwise, just use the list of arguments provided. */
4096 fn_first_arg = NULL_TREE;
4100 if (TREE_CODE (fn) == TEMPLATE_DECL)
4101 add_template_candidate (candidates,
4112 else if (!template_only)
4113 add_function_candidate (candidates,
4121 fns = OVL_NEXT (fns);
4125 /* Even unsigned enum types promote to signed int. We don't want to
4126 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4127 original argument and ARG is the argument after any conversions
4128 have been applied. We set TREE_NO_WARNING if we have added a cast
4129 from an unsigned enum type to a signed integer type. */
4132 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4134 if (orig_arg != NULL_TREE
4137 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4138 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4139 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4140 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4141 TREE_NO_WARNING (arg) = 1;
4145 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4146 bool *overloaded_p, tsubst_flags_t complain)
4148 tree orig_arg1 = arg1;
4149 tree orig_arg2 = arg2;
4150 tree orig_arg3 = arg3;
4151 struct z_candidate *candidates = 0, *cand;
4152 VEC(tree,gc) *arglist;
4155 tree result = NULL_TREE;
4156 bool result_valid_p = false;
4157 enum tree_code code2 = NOP_EXPR;
4158 enum tree_code code_orig_arg1 = ERROR_MARK;
4159 enum tree_code code_orig_arg2 = ERROR_MARK;
4165 if (error_operand_p (arg1)
4166 || error_operand_p (arg2)
4167 || error_operand_p (arg3))
4168 return error_mark_node;
4170 if (code == MODIFY_EXPR)
4172 code2 = TREE_CODE (arg3);
4174 fnname = ansi_assopname (code2);
4177 fnname = ansi_opname (code);
4179 arg1 = prep_operand (arg1);
4185 case VEC_DELETE_EXPR:
4187 /* Use build_op_new_call and build_op_delete_call instead. */
4191 /* Use build_op_call instead. */
4194 case TRUTH_ORIF_EXPR:
4195 case TRUTH_ANDIF_EXPR:
4196 case TRUTH_AND_EXPR:
4198 /* These are saved for the sake of warn_logical_operator. */
4199 code_orig_arg1 = TREE_CODE (arg1);
4200 code_orig_arg2 = TREE_CODE (arg2);
4206 arg2 = prep_operand (arg2);
4207 arg3 = prep_operand (arg3);
4209 if (code == COND_EXPR)
4210 /* Use build_conditional_expr instead. */
4212 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4213 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4216 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4217 arg2 = integer_zero_node;
4219 arglist = VEC_alloc (tree, gc, 3);
4220 VEC_quick_push (tree, arglist, arg1);
4221 if (arg2 != NULL_TREE)
4222 VEC_quick_push (tree, arglist, arg2);
4223 if (arg3 != NULL_TREE)
4224 VEC_quick_push (tree, arglist, arg3);
4226 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4227 p = conversion_obstack_alloc (0);
4229 /* Add namespace-scope operators to the list of functions to
4231 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4232 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4233 flags, &candidates);
4234 /* Add class-member operators to the candidate set. */
4235 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4239 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4240 if (fns == error_mark_node)
4242 result = error_mark_node;
4243 goto user_defined_result_ready;
4246 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4248 BASELINK_BINFO (fns),
4249 TYPE_BINFO (TREE_TYPE (arg1)),
4250 flags, &candidates);
4255 args[2] = NULL_TREE;
4257 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4263 /* For these, the built-in candidates set is empty
4264 [over.match.oper]/3. We don't want non-strict matches
4265 because exact matches are always possible with built-in
4266 operators. The built-in candidate set for COMPONENT_REF
4267 would be empty too, but since there are no such built-in
4268 operators, we accept non-strict matches for them. */
4273 strict_p = pedantic;
4277 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4282 case POSTINCREMENT_EXPR:
4283 case POSTDECREMENT_EXPR:
4284 /* Don't try anything fancy if we're not allowed to produce
4286 if (!(complain & tf_error))
4287 return error_mark_node;
4289 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4290 distinguish between prefix and postfix ++ and
4291 operator++() was used for both, so we allow this with
4293 if (flags & LOOKUP_COMPLAIN)
4295 const char *msg = (flag_permissive)
4296 ? G_("no %<%D(int)%> declared for postfix %qs,"
4297 " trying prefix operator instead")
4298 : G_("no %<%D(int)%> declared for postfix %qs");
4299 permerror (input_location, msg, fnname,
4300 operator_name_info[code].name);
4303 if (!flag_permissive)
4304 return error_mark_node;
4306 if (code == POSTINCREMENT_EXPR)
4307 code = PREINCREMENT_EXPR;
4309 code = PREDECREMENT_EXPR;
4310 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4311 overloaded_p, complain);
4314 /* The caller will deal with these. */
4319 result_valid_p = true;
4323 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4325 /* If one of the arguments of the operator represents
4326 an invalid use of member function pointer, try to report
4327 a meaningful error ... */
4328 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4329 || invalid_nonstatic_memfn_p (arg2, tf_error)
4330 || invalid_nonstatic_memfn_p (arg3, tf_error))
4331 /* We displayed the error message. */;
4334 /* ... Otherwise, report the more generic
4335 "no matching operator found" error */
4336 op_error (code, code2, arg1, arg2, arg3, "no match");
4337 print_z_candidates (candidates);
4340 result = error_mark_node;
4346 cand = tourney (candidates);
4349 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4351 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4352 print_z_candidates (candidates);
4354 result = error_mark_node;
4356 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4359 *overloaded_p = true;
4361 if (resolve_args (arglist) == NULL)
4362 result = error_mark_node;
4364 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4368 /* Give any warnings we noticed during overload resolution. */
4369 if (cand->warnings && (complain & tf_warning))
4371 struct candidate_warning *w;
4372 for (w = cand->warnings; w; w = w->next)
4373 joust (cand, w->loser, 1);
4376 /* Check for comparison of different enum types. */
4385 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4386 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4387 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4388 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4389 && (complain & tf_warning))
4391 warning (OPT_Wenum_compare,
4392 "comparison between %q#T and %q#T",
4393 TREE_TYPE (arg1), TREE_TYPE (arg2));
4400 /* We need to strip any leading REF_BIND so that bitfields
4401 don't cause errors. This should not remove any important
4402 conversions, because builtins don't apply to class
4403 objects directly. */
4404 conv = cand->convs[0];
4405 if (conv->kind == ck_ref_bind)
4406 conv = conv->u.next;
4407 arg1 = convert_like (conv, arg1, complain);
4411 /* We need to call warn_logical_operator before
4412 converting arg2 to a boolean_type. */
4413 if (complain & tf_warning)
4414 warn_logical_operator (input_location, code, boolean_type_node,
4415 code_orig_arg1, arg1,
4416 code_orig_arg2, arg2);
4418 conv = cand->convs[1];
4419 if (conv->kind == ck_ref_bind)
4420 conv = conv->u.next;
4421 arg2 = convert_like (conv, arg2, complain);
4425 conv = cand->convs[2];
4426 if (conv->kind == ck_ref_bind)
4427 conv = conv->u.next;
4428 arg3 = convert_like (conv, arg3, complain);
4434 user_defined_result_ready:
4436 /* Free all the conversions we allocated. */
4437 obstack_free (&conversion_obstack, p);
4439 if (result || result_valid_p)
4443 avoid_sign_compare_warnings (orig_arg1, arg1);
4444 avoid_sign_compare_warnings (orig_arg2, arg2);
4445 avoid_sign_compare_warnings (orig_arg3, arg3);
4450 return cp_build_modify_expr (arg1, code2, arg2, complain);
4453 return cp_build_indirect_ref (arg1, "unary *", complain);
4455 case TRUTH_ANDIF_EXPR:
4456 case TRUTH_ORIF_EXPR:
4457 case TRUTH_AND_EXPR:
4459 warn_logical_operator (input_location, code, boolean_type_node,
4460 code_orig_arg1, arg1, code_orig_arg2, arg2);
4465 case TRUNC_DIV_EXPR:
4476 case TRUNC_MOD_EXPR:
4480 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4482 case UNARY_PLUS_EXPR:
4485 case TRUTH_NOT_EXPR:
4486 case PREINCREMENT_EXPR:
4487 case POSTINCREMENT_EXPR:
4488 case PREDECREMENT_EXPR:
4489 case POSTDECREMENT_EXPR:
4492 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4495 return build_array_ref (input_location, arg1, arg2);
4498 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4502 /* The caller will deal with these. */
4514 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
4515 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
4518 non_placement_deallocation_fn_p (tree t)
4520 /* A template instance is never a usual deallocation function,
4521 regardless of its signature. */
4522 if (TREE_CODE (t) == TEMPLATE_DECL
4523 || primary_template_instantiation_p (t))
4526 /* If a class T has a member deallocation function named operator delete
4527 with exactly one parameter, then that function is a usual
4528 (non-placement) deallocation function. If class T does not declare
4529 such an operator delete but does declare a member deallocation
4530 function named operator delete with exactly two parameters, the second
4531 of which has type std::size_t (18.2), then this function is a usual
4532 deallocation function. */
4533 t = FUNCTION_ARG_CHAIN (t);
4534 if (t == void_list_node
4535 || (t && same_type_p (TREE_VALUE (t), size_type_node)
4536 && TREE_CHAIN (t) == void_list_node))
4541 /* Build a call to operator delete. This has to be handled very specially,
4542 because the restrictions on what signatures match are different from all
4543 other call instances. For a normal delete, only a delete taking (void *)
4544 or (void *, size_t) is accepted. For a placement delete, only an exact
4545 match with the placement new is accepted.
4547 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4548 ADDR is the pointer to be deleted.
4549 SIZE is the size of the memory block to be deleted.
4550 GLOBAL_P is true if the delete-expression should not consider
4551 class-specific delete operators.
4552 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4554 If this call to "operator delete" is being generated as part to
4555 deallocate memory allocated via a new-expression (as per [expr.new]
4556 which requires that if the initialization throws an exception then
4557 we call a deallocation function), then ALLOC_FN is the allocation
4561 build_op_delete_call (enum tree_code code, tree addr, tree size,
4562 bool global_p, tree placement,
4565 tree fn = NULL_TREE;
4566 tree fns, fnname, type, t;
4568 if (addr == error_mark_node)
4569 return error_mark_node;
4571 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4573 fnname = ansi_opname (code);
4575 if (CLASS_TYPE_P (type)
4576 && COMPLETE_TYPE_P (complete_type (type))
4580 If the result of the lookup is ambiguous or inaccessible, or if
4581 the lookup selects a placement deallocation function, the
4582 program is ill-formed.
4584 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4586 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4587 if (fns == error_mark_node)
4588 return error_mark_node;
4593 if (fns == NULL_TREE)
4594 fns = lookup_name_nonclass (fnname);
4596 /* Strip const and volatile from addr. */
4597 addr = cp_convert (ptr_type_node, addr);
4601 /* "A declaration of a placement deallocation function matches the
4602 declaration of a placement allocation function if it has the same
4603 number of parameters and, after parameter transformations (8.3.5),
4604 all parameter types except the first are identical."
4606 So we build up the function type we want and ask instantiate_type
4607 to get it for us. */
4608 t = FUNCTION_ARG_CHAIN (alloc_fn);
4609 t = tree_cons (NULL_TREE, ptr_type_node, t);
4610 t = build_function_type (void_type_node, t);
4612 fn = instantiate_type (t, fns, tf_none);
4613 if (fn == error_mark_node)
4616 if (BASELINK_P (fn))
4617 fn = BASELINK_FUNCTIONS (fn);
4619 /* "If the lookup finds the two-parameter form of a usual deallocation
4620 function (3.7.4.2) and that function, considered as a placement
4621 deallocation function, would have been selected as a match for the
4622 allocation function, the program is ill-formed." */
4623 if (non_placement_deallocation_fn_p (fn))
4625 /* But if the class has an operator delete (void *), then that is
4626 the usual deallocation function, so we shouldn't complain
4627 about using the operator delete (void *, size_t). */
4628 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4629 t; t = OVL_NEXT (t))
4631 tree elt = OVL_CURRENT (t);
4632 if (non_placement_deallocation_fn_p (elt)
4633 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
4636 permerror (0, "non-placement deallocation function %q+D", fn);
4637 permerror (input_location, "selected for placement delete");
4642 /* "Any non-placement deallocation function matches a non-placement
4643 allocation function. If the lookup finds a single matching
4644 deallocation function, that function will be called; otherwise, no
4645 deallocation function will be called." */
4646 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4647 t; t = OVL_NEXT (t))
4649 tree elt = OVL_CURRENT (t);
4650 if (non_placement_deallocation_fn_p (elt))
4653 /* "If a class T has a member deallocation function named
4654 operator delete with exactly one parameter, then that
4655 function is a usual (non-placement) deallocation
4656 function. If class T does not declare such an operator
4657 delete but does declare a member deallocation function named
4658 operator delete with exactly two parameters, the second of
4659 which has type std::size_t (18.2), then this function is a
4660 usual deallocation function."
4662 So (void*) beats (void*, size_t). */
4663 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4668 /* If we have a matching function, call it. */
4671 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
4673 /* If the FN is a member function, make sure that it is
4675 if (BASELINK_P (fns))
4676 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
4678 /* Core issue 901: It's ok to new a type with deleted delete. */
4679 if (DECL_DELETED_FN (fn) && alloc_fn)
4684 /* The placement args might not be suitable for overload
4685 resolution at this point, so build the call directly. */
4686 int nargs = call_expr_nargs (placement);
4687 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4690 for (i = 1; i < nargs; i++)
4691 argarray[i] = CALL_EXPR_ARG (placement, i);
4693 return build_cxx_call (fn, nargs, argarray);
4698 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4699 VEC_quick_push (tree, args, addr);
4700 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
4701 VEC_quick_push (tree, args, size);
4702 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4703 VEC_free (tree, gc, args);
4710 If no unambiguous matching deallocation function can be found,
4711 propagating the exception does not cause the object's memory to
4716 warning (0, "no corresponding deallocation function for %qD",
4721 error ("no suitable %<operator %s%> for %qT",
4722 operator_name_info[(int)code].name, type);
4723 return error_mark_node;
4726 /* If the current scope isn't allowed to access DECL along
4727 BASETYPE_PATH, give an error. The most derived class in
4728 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4729 the declaration to use in the error diagnostic. */
4732 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4734 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4736 if (!accessible_p (basetype_path, decl, true))
4738 if (TREE_PRIVATE (decl))
4739 error ("%q+#D is private", diag_decl);
4740 else if (TREE_PROTECTED (decl))
4741 error ("%q+#D is protected", diag_decl);
4743 error ("%q+#D is inaccessible", diag_decl);
4744 error ("within this context");
4751 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4752 bitwise or of LOOKUP_* values. If any errors are warnings are
4753 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4754 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4758 build_temp (tree expr, tree type, int flags,
4759 diagnostic_t *diagnostic_kind)
4764 savew = warningcount, savee = errorcount;
4765 args = make_tree_vector_single (expr);
4766 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4767 &args, type, flags, tf_warning_or_error);
4768 release_tree_vector (args);
4769 if (warningcount > savew)
4770 *diagnostic_kind = DK_WARNING;
4771 else if (errorcount > savee)
4772 *diagnostic_kind = DK_ERROR;
4774 *diagnostic_kind = DK_UNSPECIFIED;
4778 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4779 EXPR is implicitly converted to type TOTYPE.
4780 FN and ARGNUM are used for diagnostics. */
4783 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4785 tree t = non_reference (totype);
4787 /* Issue warnings about peculiar, but valid, uses of NULL. */
4788 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4791 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4794 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4797 /* Issue warnings if "false" is converted to a NULL pointer */
4798 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4799 warning (OPT_Wconversion,
4800 "converting %<false%> to pointer type for argument %P of %qD",
4804 /* Perform the conversions in CONVS on the expression EXPR. FN and
4805 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4806 indicates the `this' argument of a method. INNER is nonzero when
4807 being called to continue a conversion chain. It is negative when a
4808 reference binding will be applied, positive otherwise. If
4809 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4810 conversions will be emitted if appropriate. If C_CAST_P is true,
4811 this conversion is coming from a C-style cast; in that case,
4812 conversions to inaccessible bases are permitted. */
4815 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4816 int inner, bool issue_conversion_warnings,
4817 bool c_cast_p, tsubst_flags_t complain)
4819 tree totype = convs->type;
4820 diagnostic_t diag_kind;
4824 && convs->kind != ck_user
4825 && convs->kind != ck_list
4826 && convs->kind != ck_ambig
4827 && convs->kind != ck_ref_bind
4828 && convs->kind != ck_rvalue
4829 && convs->kind != ck_base)
4831 conversion *t = convs;
4833 /* Give a helpful error if this is bad because of excess braces. */
4834 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4835 && SCALAR_TYPE_P (totype)
4836 && CONSTRUCTOR_NELTS (expr) > 0
4837 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4838 permerror (input_location, "too many braces around initializer for %qT", totype);
4840 for (; t; t = convs->u.next)
4842 if (t->kind == ck_user || !t->bad_p)
4844 expr = convert_like_real (t, expr, fn, argnum, 1,
4845 /*issue_conversion_warnings=*/false,
4850 else if (t->kind == ck_ambig)
4851 return convert_like_real (t, expr, fn, argnum, 1,
4852 /*issue_conversion_warnings=*/false,
4855 else if (t->kind == ck_identity)
4858 if (complain & tf_error)
4860 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4862 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4865 return error_mark_node;
4867 return cp_convert (totype, expr);
4870 if (issue_conversion_warnings && (complain & tf_warning))
4871 conversion_null_warnings (totype, expr, fn, argnum);
4873 switch (convs->kind)
4877 struct z_candidate *cand = convs->cand;
4878 tree convfn = cand->fn;
4881 /* When converting from an init list we consider explicit
4882 constructors, but actually trying to call one is an error. */
4883 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4885 if (complain & tf_error)
4886 error ("converting to %qT from initializer list would use "
4887 "explicit constructor %qD", totype, convfn);
4889 return error_mark_node;
4892 /* Set user_conv_p on the argument conversions, so rvalue/base
4893 handling knows not to allow any more UDCs. */
4894 for (i = 0; i < cand->num_convs; ++i)
4895 cand->convs[i]->user_conv_p = true;
4897 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4899 /* If this is a constructor or a function returning an aggr type,
4900 we need to build up a TARGET_EXPR. */
4901 if (DECL_CONSTRUCTOR_P (convfn))
4903 expr = build_cplus_new (totype, expr);
4905 /* Remember that this was list-initialization. */
4906 if (convs->check_narrowing)
4907 TARGET_EXPR_LIST_INIT_P (expr) = true;
4913 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4915 int nelts = CONSTRUCTOR_NELTS (expr);
4917 expr = integer_zero_node;
4918 else if (nelts == 1)
4919 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4924 if (type_unknown_p (expr))
4925 expr = instantiate_type (totype, expr, complain);
4926 /* Convert a constant to its underlying value, unless we are
4927 about to bind it to a reference, in which case we need to
4928 leave it as an lvalue. */
4931 expr = decl_constant_value (expr);
4932 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4933 /* If __null has been converted to an integer type, we do not
4934 want to warn about uses of EXPR as an integer, rather than
4936 expr = build_int_cst (totype, 0);
4940 /* Call build_user_type_conversion again for the error. */
4941 return build_user_type_conversion
4942 (totype, convs->u.expr, LOOKUP_NORMAL);
4946 /* Conversion to std::initializer_list<T>. */
4947 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4948 tree new_ctor = build_constructor (init_list_type_node, NULL);
4949 unsigned len = CONSTRUCTOR_NELTS (expr);
4951 VEC(tree,gc) *parms;
4954 /* Convert all the elements. */
4955 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4957 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4958 1, false, false, complain);
4959 if (sub == error_mark_node)
4961 check_narrowing (TREE_TYPE (sub), val);
4962 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4964 /* Build up the array. */
4965 elttype = cp_build_qualified_type
4966 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4967 array = build_array_of_n_type (elttype, len);
4968 array = finish_compound_literal (array, new_ctor);
4970 parms = make_tree_vector ();
4971 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4972 VEC_safe_push (tree, gc, parms, size_int (len));
4973 /* Call the private constructor. */
4974 push_deferring_access_checks (dk_no_check);
4975 new_ctor = build_special_member_call
4976 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4977 release_tree_vector (parms);
4978 pop_deferring_access_checks ();
4979 return build_cplus_new (totype, new_ctor);
4983 return get_target_expr (digest_init (totype, expr));
4989 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4990 convs->kind == ck_ref_bind ? -1 : 1,
4991 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4994 if (expr == error_mark_node)
4995 return error_mark_node;
4997 switch (convs->kind)
5000 expr = convert_bitfield_to_declared_type (expr);
5001 if (! MAYBE_CLASS_TYPE_P (totype))
5003 /* Else fall through. */
5005 if (convs->kind == ck_base && !convs->need_temporary_p)
5007 /* We are going to bind a reference directly to a base-class
5008 subobject of EXPR. */
5009 /* Build an expression for `*((base*) &expr)'. */
5010 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5011 expr = convert_to_base (expr, build_pointer_type (totype),
5012 !c_cast_p, /*nonnull=*/true);
5013 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
5017 /* Copy-initialization where the cv-unqualified version of the source
5018 type is the same class as, or a derived class of, the class of the
5019 destination [is treated as direct-initialization]. [dcl.init] */
5020 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5021 if (convs->user_conv_p)
5022 /* This conversion is being done in the context of a user-defined
5023 conversion (i.e. the second step of copy-initialization), so
5024 don't allow any more. */
5025 flags |= LOOKUP_NO_CONVERSION;
5026 expr = build_temp (expr, totype, flags, &diag_kind);
5027 if (diag_kind && fn)
5029 if ((complain & tf_error))
5030 emit_diagnostic (diag_kind, input_location, 0,
5031 " initializing argument %P of %qD", argnum, fn);
5032 else if (diag_kind == DK_ERROR)
5033 return error_mark_node;
5035 return build_cplus_new (totype, expr);
5039 tree ref_type = totype;
5041 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5042 && real_lvalue_p (expr))
5044 if (complain & tf_error)
5046 error ("cannot bind %qT lvalue to %qT",
5047 TREE_TYPE (expr), totype);
5049 error (" initializing argument %P of %q+D", argnum, fn);
5051 return error_mark_node;
5054 /* If necessary, create a temporary.
5056 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5057 that need temporaries, even when their types are reference
5058 compatible with the type of reference being bound, so the
5059 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5061 if (convs->need_temporary_p
5062 || TREE_CODE (expr) == CONSTRUCTOR
5063 || TREE_CODE (expr) == VA_ARG_EXPR)
5065 tree type = convs->u.next->type;
5066 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5068 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
5069 && !TYPE_REF_IS_RVALUE (ref_type))
5071 if (complain & tf_error)
5073 /* If the reference is volatile or non-const, we
5074 cannot create a temporary. */
5075 if (lvalue & clk_bitfield)
5076 error ("cannot bind bitfield %qE to %qT",
5078 else if (lvalue & clk_packed)
5079 error ("cannot bind packed field %qE to %qT",
5082 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5084 return error_mark_node;
5086 /* If the source is a packed field, and we must use a copy
5087 constructor, then building the target expr will require
5088 binding the field to the reference parameter to the
5089 copy constructor, and we'll end up with an infinite
5090 loop. If we can use a bitwise copy, then we'll be
5092 if ((lvalue & clk_packed)
5093 && CLASS_TYPE_P (type)
5094 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
5096 if (complain & tf_error)
5097 error ("cannot bind packed field %qE to %qT",
5099 return error_mark_node;
5101 if (lvalue & clk_bitfield)
5103 expr = convert_bitfield_to_declared_type (expr);
5104 expr = fold_convert (type, expr);
5106 expr = build_target_expr_with_type (expr, type);
5109 /* Take the address of the thing to which we will bind the
5111 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5112 if (expr == error_mark_node)
5113 return error_mark_node;
5115 /* Convert it to a pointer to the type referred to by the
5116 reference. This will adjust the pointer if a derived to
5117 base conversion is being performed. */
5118 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5120 /* Convert the pointer to the desired reference type. */
5121 return build_nop (ref_type, expr);
5125 return decay_conversion (expr);
5128 /* Warn about deprecated conversion if appropriate. */
5129 string_conv_p (totype, expr, 1);
5134 expr = convert_to_base (expr, totype, !c_cast_p,
5136 return build_nop (totype, expr);
5139 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5146 if (convs->check_narrowing)
5147 check_narrowing (totype, expr);
5149 if (issue_conversion_warnings && (complain & tf_warning))
5150 expr = convert_and_check (totype, expr);
5152 expr = convert (totype, expr);
5157 /* ARG is being passed to a varargs function. Perform any conversions
5158 required. Return the converted value. */
5161 convert_arg_to_ellipsis (tree arg)
5165 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5166 standard conversions are performed. */
5167 arg = decay_conversion (arg);
5170 If the argument has integral or enumeration type that is subject
5171 to the integral promotions (_conv.prom_), or a floating point
5172 type that is subject to the floating point promotion
5173 (_conv.fpprom_), the value of the argument is converted to the
5174 promoted type before the call. */
5175 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5176 && (TYPE_PRECISION (TREE_TYPE (arg))
5177 < TYPE_PRECISION (double_type_node))
5178 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (arg))))
5179 arg = convert_to_real (double_type_node, arg);
5180 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5181 arg = perform_integral_promotions (arg);
5183 arg = require_complete_type (arg);
5185 if (arg != error_mark_node
5186 && (type_has_nontrivial_copy_init (TREE_TYPE (arg))
5187 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (arg))))
5189 /* [expr.call] 5.2.2/7:
5190 Passing a potentially-evaluated argument of class type (Clause 9)
5191 with a non-trivial copy constructor or a non-trivial destructor
5192 with no corresponding parameter is conditionally-supported, with
5193 implementation-defined semantics.
5195 We used to just warn here and do a bitwise copy, but now
5196 cp_expr_size will abort if we try to do that.
5198 If the call appears in the context of a sizeof expression,
5199 it is not potentially-evaluated. */
5200 if (cp_unevaluated_operand == 0)
5201 error ("cannot pass objects of non-trivially-copyable "
5202 "type %q#T through %<...%>", TREE_TYPE (arg));
5208 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5211 build_x_va_arg (tree expr, tree type)
5213 if (processing_template_decl)
5214 return build_min (VA_ARG_EXPR, type, expr);
5216 type = complete_type_or_else (type, NULL_TREE);
5218 if (expr == error_mark_node || !type)
5219 return error_mark_node;
5221 if (type_has_nontrivial_copy_init (type)
5222 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5223 || TREE_CODE (type) == REFERENCE_TYPE)
5225 /* Remove reference types so we don't ICE later on. */
5226 tree type1 = non_reference (type);
5227 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5228 error ("cannot receive objects of non-trivially-copyable type %q#T "
5229 "through %<...%>; ", type);
5230 expr = convert (build_pointer_type (type1), null_node);
5231 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
5235 return build_va_arg (input_location, expr, type);
5238 /* TYPE has been given to va_arg. Apply the default conversions which
5239 would have happened when passed via ellipsis. Return the promoted
5240 type, or the passed type if there is no change. */
5243 cxx_type_promotes_to (tree type)
5247 /* Perform the array-to-pointer and function-to-pointer
5249 type = type_decays_to (type);
5251 promote = type_promotes_to (type);
5252 if (same_type_p (type, promote))
5258 /* ARG is a default argument expression being passed to a parameter of
5259 the indicated TYPE, which is a parameter to FN. Do any required
5260 conversions. Return the converted value. */
5262 static GTY(()) VEC(tree,gc) *default_arg_context;
5265 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5270 /* If the ARG is an unparsed default argument expression, the
5271 conversion cannot be performed. */
5272 if (TREE_CODE (arg) == DEFAULT_ARG)
5274 error ("the default argument for parameter %d of %qD has "
5275 "not yet been parsed",
5277 return error_mark_node;
5280 /* Detect recursion. */
5281 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5284 error ("recursive evaluation of default argument for %q#D", fn);
5285 return error_mark_node;
5287 VEC_safe_push (tree, gc, default_arg_context, fn);
5289 if (fn && DECL_TEMPLATE_INFO (fn))
5290 arg = tsubst_default_argument (fn, type, arg);
5296 The names in the expression are bound, and the semantic
5297 constraints are checked, at the point where the default
5298 expressions appears.
5300 we must not perform access checks here. */
5301 push_deferring_access_checks (dk_no_check);
5302 arg = break_out_target_exprs (arg);
5303 if (TREE_CODE (arg) == CONSTRUCTOR)
5305 arg = digest_init (type, arg);
5306 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5307 "default argument", fn, parmnum,
5308 tf_warning_or_error);
5312 /* We must make a copy of ARG, in case subsequent processing
5313 alters any part of it. For example, during gimplification a
5314 cast of the form (T) &X::f (where "f" is a member function)
5315 will lead to replacing the PTRMEM_CST for &X::f with a
5316 VAR_DECL. We can avoid the copy for constants, since they
5317 are never modified in place. */
5318 if (!CONSTANT_CLASS_P (arg))
5319 arg = unshare_expr (arg);
5320 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5321 "default argument", fn, parmnum,
5322 tf_warning_or_error);
5323 arg = convert_for_arg_passing (type, arg);
5325 pop_deferring_access_checks();
5327 VEC_pop (tree, default_arg_context);
5332 /* Returns the type which will really be used for passing an argument of
5336 type_passed_as (tree type)
5338 /* Pass classes with copy ctors by invisible reference. */
5339 if (TREE_ADDRESSABLE (type))
5341 type = build_reference_type (type);
5342 /* There are no other pointers to this temporary. */
5343 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5345 else if (targetm.calls.promote_prototypes (type)
5346 && INTEGRAL_TYPE_P (type)
5347 && COMPLETE_TYPE_P (type)
5348 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5349 TYPE_SIZE (integer_type_node)))
5350 type = integer_type_node;
5355 /* Actually perform the appropriate conversion. */
5358 convert_for_arg_passing (tree type, tree val)
5362 /* If VAL is a bitfield, then -- since it has already been converted
5363 to TYPE -- it cannot have a precision greater than TYPE.
5365 If it has a smaller precision, we must widen it here. For
5366 example, passing "int f:3;" to a function expecting an "int" will
5367 not result in any conversion before this point.
5369 If the precision is the same we must not risk widening. For
5370 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5371 often have type "int", even though the C++ type for the field is
5372 "long long". If the value is being passed to a function
5373 expecting an "int", then no conversions will be required. But,
5374 if we call convert_bitfield_to_declared_type, the bitfield will
5375 be converted to "long long". */
5376 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5378 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5379 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5381 if (val == error_mark_node)
5383 /* Pass classes with copy ctors by invisible reference. */
5384 else if (TREE_ADDRESSABLE (type))
5385 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5386 else if (targetm.calls.promote_prototypes (type)
5387 && INTEGRAL_TYPE_P (type)
5388 && COMPLETE_TYPE_P (type)
5389 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5390 TYPE_SIZE (integer_type_node)))
5391 val = perform_integral_promotions (val);
5392 if (warn_missing_format_attribute)
5394 tree rhstype = TREE_TYPE (val);
5395 const enum tree_code coder = TREE_CODE (rhstype);
5396 const enum tree_code codel = TREE_CODE (type);
5397 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5399 && check_missing_format_attribute (type, rhstype))
5400 warning (OPT_Wmissing_format_attribute,
5401 "argument of function call might be a candidate for a format attribute");
5406 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5407 which no conversions at all should be done. This is true for some
5408 builtins which don't act like normal functions. */
5411 magic_varargs_p (tree fn)
5413 if (DECL_BUILT_IN (fn))
5414 switch (DECL_FUNCTION_CODE (fn))
5416 case BUILT_IN_CLASSIFY_TYPE:
5417 case BUILT_IN_CONSTANT_P:
5418 case BUILT_IN_NEXT_ARG:
5419 case BUILT_IN_VA_START:
5423 return lookup_attribute ("type generic",
5424 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5430 /* Subroutine of the various build_*_call functions. Overload resolution
5431 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5432 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5433 bitmask of various LOOKUP_* flags which apply to the call itself. */
5436 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5439 const VEC(tree,gc) *args = cand->args;
5440 tree first_arg = cand->first_arg;
5441 conversion **convs = cand->convs;
5443 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5448 unsigned int arg_index = 0;
5452 bool already_used = false;
5454 /* In a template, there is no need to perform all of the work that
5455 is normally done. We are only interested in the type of the call
5456 expression, i.e., the return type of the function. Any semantic
5457 errors will be deferred until the template is instantiated. */
5458 if (processing_template_decl)
5462 const tree *argarray;
5465 return_type = TREE_TYPE (TREE_TYPE (fn));
5466 nargs = VEC_length (tree, args);
5467 if (first_arg == NULL_TREE)
5468 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5476 alcarray = XALLOCAVEC (tree, nargs);
5477 alcarray[0] = first_arg;
5478 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5479 alcarray[ix + 1] = arg;
5480 argarray = alcarray;
5482 expr = build_call_array_loc (input_location,
5483 return_type, build_addr_func (fn), nargs,
5485 if (TREE_THIS_VOLATILE (fn) && cfun)
5486 current_function_returns_abnormally = 1;
5487 if (!VOID_TYPE_P (return_type))
5488 require_complete_type (return_type);
5489 return convert_from_reference (expr);
5492 /* Give any warnings we noticed during overload resolution. */
5495 struct candidate_warning *w;
5496 for (w = cand->warnings; w; w = w->next)
5497 joust (cand, w->loser, 1);
5500 /* Make =delete work with SFINAE. */
5501 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5502 return error_mark_node;
5504 if (DECL_FUNCTION_MEMBER_P (fn))
5506 /* If FN is a template function, two cases must be considered.
5511 template <class T> void f();
5513 template <class T> struct B {
5517 struct C : A, B<int> {
5519 using B<int>::g; // #2
5522 In case #1 where `A::f' is a member template, DECL_ACCESS is
5523 recorded in the primary template but not in its specialization.
5524 We check access of FN using its primary template.
5526 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5527 because it is a member of class template B, DECL_ACCESS is
5528 recorded in the specialization `B<int>::g'. We cannot use its
5529 primary template because `B<T>::g' and `B<int>::g' may have
5530 different access. */
5531 if (DECL_TEMPLATE_INFO (fn)
5532 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5533 perform_or_defer_access_check (cand->access_path,
5534 DECL_TI_TEMPLATE (fn), fn);
5536 perform_or_defer_access_check (cand->access_path, fn, fn);
5539 /* Find maximum size of vector to hold converted arguments. */
5540 parmlen = list_length (parm);
5541 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5542 if (parmlen > nargs)
5544 argarray = (tree *) alloca (nargs * sizeof (tree));
5546 /* The implicit parameters to a constructor are not considered by overload
5547 resolution, and must be of the proper type. */
5548 if (DECL_CONSTRUCTOR_P (fn))
5550 if (first_arg != NULL_TREE)
5552 argarray[j++] = first_arg;
5553 first_arg = NULL_TREE;
5557 argarray[j++] = VEC_index (tree, args, arg_index);
5560 parm = TREE_CHAIN (parm);
5561 /* We should never try to call the abstract constructor. */
5562 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5564 if (DECL_HAS_VTT_PARM_P (fn))
5566 argarray[j++] = VEC_index (tree, args, arg_index);
5568 parm = TREE_CHAIN (parm);
5571 /* Bypass access control for 'this' parameter. */
5572 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5574 tree parmtype = TREE_VALUE (parm);
5575 tree arg = (first_arg != NULL_TREE
5577 : VEC_index (tree, args, arg_index));
5578 tree argtype = TREE_TYPE (arg);
5582 if (convs[i]->bad_p)
5584 if (complain & tf_error)
5585 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5586 TREE_TYPE (argtype), fn);
5588 return error_mark_node;
5591 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5592 X is called for an object that is not of type X, or of a type
5593 derived from X, the behavior is undefined.
5595 So we can assume that anything passed as 'this' is non-null, and
5596 optimize accordingly. */
5597 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5598 /* Convert to the base in which the function was declared. */
5599 gcc_assert (cand->conversion_path != NULL_TREE);
5600 converted_arg = build_base_path (PLUS_EXPR,
5602 cand->conversion_path,
5604 /* Check that the base class is accessible. */
5605 if (!accessible_base_p (TREE_TYPE (argtype),
5606 BINFO_TYPE (cand->conversion_path), true))
5607 error ("%qT is not an accessible base of %qT",
5608 BINFO_TYPE (cand->conversion_path),
5609 TREE_TYPE (argtype));
5610 /* If fn was found by a using declaration, the conversion path
5611 will be to the derived class, not the base declaring fn. We
5612 must convert from derived to base. */
5613 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5614 TREE_TYPE (parmtype), ba_unique, NULL);
5615 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5618 argarray[j++] = converted_arg;
5619 parm = TREE_CHAIN (parm);
5620 if (first_arg != NULL_TREE)
5621 first_arg = NULL_TREE;
5628 gcc_assert (first_arg == NULL_TREE);
5629 for (; arg_index < VEC_length (tree, args) && parm;
5630 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5632 tree type = TREE_VALUE (parm);
5636 /* Don't make a copy here if build_call is going to. */
5637 if (conv->kind == ck_rvalue
5638 && COMPLETE_TYPE_P (complete_type (type))
5639 && !TREE_ADDRESSABLE (type))
5640 conv = conv->u.next;
5642 /* Warn about initializer_list deduction that isn't currently in the
5644 if (cxx_dialect > cxx98
5645 && flag_deduce_init_list
5646 && cand->template_decl
5647 && is_std_init_list (non_reference (type)))
5649 tree tmpl = TI_TEMPLATE (cand->template_decl);
5650 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
5651 tree patparm = get_pattern_parm (realparm, tmpl);
5653 if (!is_std_init_list (non_reference (TREE_TYPE (patparm))))
5655 pedwarn (input_location, 0, "deducing %qT as %qT",
5656 non_reference (TREE_TYPE (patparm)),
5657 non_reference (type));
5658 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
5659 pedwarn (input_location, 0,
5660 " (you can disable this with -fno-deduce-init-list)");
5664 val = convert_like_with_context
5665 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5668 val = convert_for_arg_passing (type, val);
5669 if (val == error_mark_node)
5670 return error_mark_node;
5672 argarray[j++] = val;
5675 /* Default arguments */
5676 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5677 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5678 TREE_PURPOSE (parm),
5681 for (; arg_index < VEC_length (tree, args); ++arg_index)
5683 tree a = VEC_index (tree, args, arg_index);
5684 if (magic_varargs_p (fn))
5685 /* Do no conversions for magic varargs. */;
5687 a = convert_arg_to_ellipsis (a);
5691 gcc_assert (j <= nargs);
5694 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5695 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5697 /* Avoid actually calling copy constructors and copy assignment operators,
5700 if (! flag_elide_constructors)
5701 /* Do things the hard way. */;
5702 else if (cand->num_convs == 1
5703 && (DECL_COPY_CONSTRUCTOR_P (fn)
5704 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5707 tree arg = argarray[num_artificial_parms_for (fn)];
5710 /* Pull out the real argument, disregarding const-correctness. */
5712 while (CONVERT_EXPR_P (targ)
5713 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5714 targ = TREE_OPERAND (targ, 0);
5715 if (TREE_CODE (targ) == ADDR_EXPR)
5717 targ = TREE_OPERAND (targ, 0);
5718 if (!same_type_ignoring_top_level_qualifiers_p
5719 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5728 arg = cp_build_indirect_ref (arg, 0, complain);
5730 if (TREE_CODE (arg) == TARGET_EXPR
5731 && TARGET_EXPR_LIST_INIT_P (arg))
5733 /* Copy-list-initialization doesn't require the copy constructor
5736 /* [class.copy]: the copy constructor is implicitly defined even if
5737 the implementation elided its use. */
5738 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5741 already_used = true;
5744 /* If we're creating a temp and we already have one, don't create a
5745 new one. If we're not creating a temp but we get one, use
5746 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5747 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5748 temp or an INIT_EXPR otherwise. */
5749 fa = (cand->first_arg != NULL_TREE
5751 : VEC_index (tree, args, 0));
5752 if (integer_zerop (fa))
5754 if (TREE_CODE (arg) == TARGET_EXPR)
5756 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5757 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5759 else if (TREE_CODE (arg) == TARGET_EXPR
5760 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5761 && !move_fn_p (fn)))
5763 tree to = stabilize_reference (cp_build_indirect_ref (fa, 0,
5766 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5770 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5772 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5774 tree to = stabilize_reference
5775 (cp_build_indirect_ref (argarray[0], 0, complain));
5776 tree type = TREE_TYPE (to);
5777 tree as_base = CLASSTYPE_AS_BASE (type);
5778 tree arg = argarray[1];
5780 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5782 arg = cp_build_indirect_ref (arg, 0, complain);
5783 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5787 /* We must only copy the non-tail padding parts.
5788 Use __builtin_memcpy for the bitwise copy.
5789 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5790 instead of an explicit call to memcpy. */
5792 tree arg0, arg1, arg2, t;
5793 tree test = NULL_TREE;
5795 arg2 = TYPE_SIZE_UNIT (as_base);
5797 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5799 if (!can_trust_pointer_alignment ())
5801 /* If we can't be sure about pointer alignment, a call
5802 to __builtin_memcpy is expanded as a call to memcpy, which
5803 is invalid with identical args. Otherwise it is
5804 expanded as a block move, which should be safe. */
5805 arg0 = save_expr (arg0);
5806 arg1 = save_expr (arg1);
5807 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5809 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5810 t = build_call_n (t, 3, arg0, arg1, arg2);
5812 t = convert (TREE_TYPE (arg0), t);
5814 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5815 val = cp_build_indirect_ref (t, 0, complain);
5816 TREE_NO_WARNING (val) = 1;
5825 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5828 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5831 gcc_assert (binfo && binfo != error_mark_node);
5833 /* Warn about deprecated virtual functions now, since we're about
5834 to throw away the decl. */
5835 if (TREE_DEPRECATED (fn))
5836 warn_deprecated_use (fn, NULL_TREE);
5838 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5839 if (TREE_SIDE_EFFECTS (argarray[0]))
5840 argarray[0] = save_expr (argarray[0]);
5841 t = build_pointer_type (TREE_TYPE (fn));
5842 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5843 fn = build_java_interface_fn_ref (fn, argarray[0]);
5845 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5849 fn = build_addr_func (fn);
5851 return build_cxx_call (fn, nargs, argarray);
5854 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5855 This function performs no overload resolution, conversion, or other
5856 high-level operations. */
5859 build_cxx_call (tree fn, int nargs, tree *argarray)
5863 fn = build_call_a (fn, nargs, argarray);
5865 /* If this call might throw an exception, note that fact. */
5866 fndecl = get_callee_fndecl (fn);
5867 if ((!fndecl || !TREE_NOTHROW (fndecl))
5868 && at_function_scope_p ()
5870 cp_function_chain->can_throw = 1;
5872 /* Check that arguments to builtin functions match the expectations. */
5874 && DECL_BUILT_IN (fndecl)
5875 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5876 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5877 return error_mark_node;
5879 /* Some built-in function calls will be evaluated at compile-time in
5881 fn = fold_if_not_in_template (fn);
5883 if (VOID_TYPE_P (TREE_TYPE (fn)))
5886 fn = require_complete_type (fn);
5887 if (fn == error_mark_node)
5888 return error_mark_node;
5890 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5891 fn = build_cplus_new (TREE_TYPE (fn), fn);
5892 return convert_from_reference (fn);
5895 static GTY(()) tree java_iface_lookup_fn;
5897 /* Make an expression which yields the address of the Java interface
5898 method FN. This is achieved by generating a call to libjava's
5899 _Jv_LookupInterfaceMethodIdx(). */
5902 build_java_interface_fn_ref (tree fn, tree instance)
5904 tree lookup_fn, method, idx;
5905 tree klass_ref, iface, iface_ref;
5908 if (!java_iface_lookup_fn)
5910 tree endlink = build_void_list_node ();
5911 tree t = tree_cons (NULL_TREE, ptr_type_node,
5912 tree_cons (NULL_TREE, ptr_type_node,
5913 tree_cons (NULL_TREE, java_int_type_node,
5915 java_iface_lookup_fn
5916 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5917 build_function_type (ptr_type_node, t),
5918 0, NOT_BUILT_IN, NULL, NULL_TREE);
5921 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5922 This is the first entry in the vtable. */
5923 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5924 tf_warning_or_error),
5927 /* Get the java.lang.Class pointer for the interface being called. */
5928 iface = DECL_CONTEXT (fn);
5929 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5930 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5931 || DECL_CONTEXT (iface_ref) != iface)
5933 error ("could not find class$ field in java interface type %qT",
5935 return error_mark_node;
5937 iface_ref = build_address (iface_ref);
5938 iface_ref = convert (build_pointer_type (iface), iface_ref);
5940 /* Determine the itable index of FN. */
5942 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5944 if (!DECL_VIRTUAL_P (method))
5950 idx = build_int_cst (NULL_TREE, i);
5952 lookup_fn = build1 (ADDR_EXPR,
5953 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5954 java_iface_lookup_fn);
5955 return build_call_nary (ptr_type_node, lookup_fn,
5956 3, klass_ref, iface_ref, idx);
5959 /* Returns the value to use for the in-charge parameter when making a
5960 call to a function with the indicated NAME.
5962 FIXME:Can't we find a neater way to do this mapping? */
5965 in_charge_arg_for_name (tree name)
5967 if (name == base_ctor_identifier
5968 || name == base_dtor_identifier)
5969 return integer_zero_node;
5970 else if (name == complete_ctor_identifier)
5971 return integer_one_node;
5972 else if (name == complete_dtor_identifier)
5973 return integer_two_node;
5974 else if (name == deleting_dtor_identifier)
5975 return integer_three_node;
5977 /* This function should only be called with one of the names listed
5983 /* Build a call to a constructor, destructor, or an assignment
5984 operator for INSTANCE, an expression with class type. NAME
5985 indicates the special member function to call; *ARGS are the
5986 arguments. ARGS may be NULL. This may change ARGS. BINFO
5987 indicates the base of INSTANCE that is to be passed as the `this'
5988 parameter to the member function called.
5990 FLAGS are the LOOKUP_* flags to use when processing the call.
5992 If NAME indicates a complete object constructor, INSTANCE may be
5993 NULL_TREE. In this case, the caller will call build_cplus_new to
5994 store the newly constructed object into a VAR_DECL. */
5997 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
5998 tree binfo, int flags, tsubst_flags_t complain)
6001 /* The type of the subobject to be constructed or destroyed. */
6003 VEC(tree,gc) *allocated = NULL;
6006 gcc_assert (name == complete_ctor_identifier
6007 || name == base_ctor_identifier
6008 || name == complete_dtor_identifier
6009 || name == base_dtor_identifier
6010 || name == deleting_dtor_identifier
6011 || name == ansi_assopname (NOP_EXPR));
6014 /* Resolve the name. */
6015 if (!complete_type_or_else (binfo, NULL_TREE))
6016 return error_mark_node;
6018 binfo = TYPE_BINFO (binfo);
6021 gcc_assert (binfo != NULL_TREE);
6023 class_type = BINFO_TYPE (binfo);
6025 /* Handle the special case where INSTANCE is NULL_TREE. */
6026 if (name == complete_ctor_identifier && !instance)
6028 instance = build_int_cst (build_pointer_type (class_type), 0);
6029 instance = build1 (INDIRECT_REF, class_type, instance);
6033 if (name == complete_dtor_identifier
6034 || name == base_dtor_identifier
6035 || name == deleting_dtor_identifier)
6036 gcc_assert (args == NULL || VEC_empty (tree, *args));
6038 /* Convert to the base class, if necessary. */
6039 if (!same_type_ignoring_top_level_qualifiers_p
6040 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6042 if (name != ansi_assopname (NOP_EXPR))
6043 /* For constructors and destructors, either the base is
6044 non-virtual, or it is virtual but we are doing the
6045 conversion from a constructor or destructor for the
6046 complete object. In either case, we can convert
6048 instance = convert_to_base_statically (instance, binfo);
6050 /* However, for assignment operators, we must convert
6051 dynamically if the base is virtual. */
6052 instance = build_base_path (PLUS_EXPR, instance,
6053 binfo, /*nonnull=*/1);
6057 gcc_assert (instance != NULL_TREE);
6059 fns = lookup_fnfields (binfo, name, 1);
6061 /* When making a call to a constructor or destructor for a subobject
6062 that uses virtual base classes, pass down a pointer to a VTT for
6064 if ((name == base_ctor_identifier
6065 || name == base_dtor_identifier)
6066 && CLASSTYPE_VBASECLASSES (class_type))
6071 /* If the current function is a complete object constructor
6072 or destructor, then we fetch the VTT directly.
6073 Otherwise, we look it up using the VTT we were given. */
6074 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6075 vtt = decay_conversion (vtt);
6076 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6077 build2 (EQ_EXPR, boolean_type_node,
6078 current_in_charge_parm, integer_zero_node),
6081 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6082 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6083 BINFO_SUBVTT_INDEX (binfo));
6087 allocated = make_tree_vector ();
6091 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6094 ret = build_new_method_call (instance, fns, args,
6095 TYPE_BINFO (BINFO_TYPE (binfo)),
6099 if (allocated != NULL)
6100 release_tree_vector (allocated);
6105 /* Return the NAME, as a C string. The NAME indicates a function that
6106 is a member of TYPE. *FREE_P is set to true if the caller must
6107 free the memory returned.
6109 Rather than go through all of this, we should simply set the names
6110 of constructors and destructors appropriately, and dispense with
6111 ctor_identifier, dtor_identifier, etc. */
6114 name_as_c_string (tree name, tree type, bool *free_p)
6118 /* Assume that we will not allocate memory. */
6120 /* Constructors and destructors are special. */
6121 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6124 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6125 /* For a destructor, add the '~'. */
6126 if (name == complete_dtor_identifier
6127 || name == base_dtor_identifier
6128 || name == deleting_dtor_identifier)
6130 pretty_name = concat ("~", pretty_name, NULL);
6131 /* Remember that we need to free the memory allocated. */
6135 else if (IDENTIFIER_TYPENAME_P (name))
6137 pretty_name = concat ("operator ",
6138 type_as_string_translate (TREE_TYPE (name),
6139 TFF_PLAIN_IDENTIFIER),
6141 /* Remember that we need to free the memory allocated. */
6145 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6150 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6151 be set, upon return, to the function called. ARGS may be NULL.
6152 This may change ARGS. */
6155 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6156 tree conversion_path, int flags,
6157 tree *fn_p, tsubst_flags_t complain)
6159 struct z_candidate *candidates = 0, *cand;
6160 tree explicit_targs = NULL_TREE;
6161 tree basetype = NULL_TREE;
6164 tree first_mem_arg = NULL_TREE;
6167 bool skip_first_for_error;
6168 VEC(tree,gc) *user_args;
6172 int template_only = 0;
6176 VEC(tree,gc) *orig_args = NULL;
6179 gcc_assert (instance != NULL_TREE);
6181 /* We don't know what function we're going to call, yet. */
6185 if (error_operand_p (instance)
6186 || error_operand_p (fns))
6187 return error_mark_node;
6189 if (!BASELINK_P (fns))
6191 if (complain & tf_error)
6192 error ("call to non-function %qD", fns);
6193 return error_mark_node;
6196 orig_instance = instance;
6199 /* Dismantle the baselink to collect all the information we need. */
6200 if (!conversion_path)
6201 conversion_path = BASELINK_BINFO (fns);
6202 access_binfo = BASELINK_ACCESS_BINFO (fns);
6203 optype = BASELINK_OPTYPE (fns);
6204 fns = BASELINK_FUNCTIONS (fns);
6205 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6207 explicit_targs = TREE_OPERAND (fns, 1);
6208 fns = TREE_OPERAND (fns, 0);
6211 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6212 || TREE_CODE (fns) == TEMPLATE_DECL
6213 || TREE_CODE (fns) == OVERLOAD);
6214 fn = get_first_fn (fns);
6215 name = DECL_NAME (fn);
6217 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6218 gcc_assert (CLASS_TYPE_P (basetype));
6220 if (processing_template_decl)
6222 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6223 instance = build_non_dependent_expr (instance);
6225 make_args_non_dependent (*args);
6228 /* Figure out whether to skip the first argument for the error
6229 message we will display to users if an error occurs. We don't
6230 want to display any compiler-generated arguments. The "this"
6231 pointer hasn't been added yet. However, we must remove the VTT
6232 pointer if this is a call to a base-class constructor or
6234 skip_first_for_error = false;
6235 user_args = args == NULL ? NULL : *args;
6236 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6238 /* Callers should explicitly indicate whether they want to construct
6239 the complete object or just the part without virtual bases. */
6240 gcc_assert (name != ctor_identifier);
6241 /* Similarly for destructors. */
6242 gcc_assert (name != dtor_identifier);
6243 /* Remove the VTT pointer, if present. */
6244 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6245 && CLASSTYPE_VBASECLASSES (basetype))
6246 skip_first_for_error = true;
6249 /* Process the argument list. */
6250 if (args != NULL && *args != NULL)
6252 *args = resolve_args (*args);
6254 return error_mark_node;
6257 instance_ptr = build_this (instance);
6259 /* It's OK to call destructors and constructors on cv-qualified objects.
6260 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6262 if (DECL_DESTRUCTOR_P (fn)
6263 || DECL_CONSTRUCTOR_P (fn))
6265 tree type = build_pointer_type (basetype);
6266 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6267 instance_ptr = build_nop (type, instance_ptr);
6269 if (DECL_DESTRUCTOR_P (fn))
6270 name = complete_dtor_identifier;
6272 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6273 initializer, not T({ }). If the type doesn't have a list ctor,
6274 break apart the list into separate ctor args. */
6275 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6276 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6277 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6278 && !TYPE_HAS_LIST_CTOR (basetype))
6280 gcc_assert (VEC_length (tree, *args) == 1);
6281 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6284 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6285 first_mem_arg = instance_ptr;
6287 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6288 p = conversion_obstack_alloc (0);
6290 for (fn = fns; fn; fn = OVL_NEXT (fn))
6292 tree t = OVL_CURRENT (fn);
6293 tree this_first_arg;
6295 /* We can end up here for copy-init of same or base class. */
6296 if ((flags & LOOKUP_ONLYCONVERTING)
6297 && DECL_NONCONVERTING_P (t))
6300 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6301 this_first_arg = first_mem_arg;
6303 this_first_arg = NULL_TREE;
6305 if (TREE_CODE (t) == TEMPLATE_DECL)
6306 /* A member template. */
6307 add_template_candidate (&candidates, t,
6311 args == NULL ? NULL : *args,
6317 else if (! template_only)
6318 add_function_candidate (&candidates, t,
6321 args == NULL ? NULL : *args,
6327 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6330 if (complain & tf_error)
6332 if (!COMPLETE_TYPE_P (basetype))
6333 cxx_incomplete_type_error (instance_ptr, basetype);
6340 pretty_name = name_as_c_string (name, basetype, &free_p);
6341 arglist = build_tree_list_vec (user_args);
6342 if (skip_first_for_error)
6343 arglist = TREE_CHAIN (arglist);
6344 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6345 basetype, pretty_name, arglist,
6346 TREE_TYPE (TREE_TYPE (instance_ptr)));
6350 print_z_candidates (candidates);
6352 call = error_mark_node;
6356 cand = tourney (candidates);
6363 if (complain & tf_error)
6365 pretty_name = name_as_c_string (name, basetype, &free_p);
6366 arglist = build_tree_list_vec (user_args);
6367 if (skip_first_for_error)
6368 arglist = TREE_CHAIN (arglist);
6369 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6371 print_z_candidates (candidates);
6375 call = error_mark_node;
6381 if (!(flags & LOOKUP_NONVIRTUAL)
6382 && DECL_PURE_VIRTUAL_P (fn)
6383 && instance == current_class_ref
6384 && (DECL_CONSTRUCTOR_P (current_function_decl)
6385 || DECL_DESTRUCTOR_P (current_function_decl))
6386 && (complain & tf_warning))
6387 /* This is not an error, it is runtime undefined
6389 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6390 "abstract virtual %q#D called from constructor"
6391 : "abstract virtual %q#D called from destructor"),
6394 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6395 && is_dummy_object (instance_ptr))
6397 if (complain & tf_error)
6398 error ("cannot call member function %qD without object",
6400 call = error_mark_node;
6404 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6405 && resolves_to_fixed_type_p (instance, 0))
6406 flags |= LOOKUP_NONVIRTUAL;
6407 /* Now we know what function is being called. */
6410 /* Build the actual CALL_EXPR. */
6411 call = build_over_call (cand, flags, complain);
6412 /* In an expression of the form `a->f()' where `f' turns
6413 out to be a static member function, `a' is
6414 none-the-less evaluated. */
6415 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6416 && !is_dummy_object (instance_ptr)
6417 && TREE_SIDE_EFFECTS (instance_ptr))
6418 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6419 instance_ptr, call);
6420 else if (call != error_mark_node
6421 && DECL_DESTRUCTOR_P (cand->fn)
6422 && !VOID_TYPE_P (TREE_TYPE (call)))
6423 /* An explicit call of the form "x->~X()" has type
6424 "void". However, on platforms where destructors
6425 return "this" (i.e., those where
6426 targetm.cxx.cdtor_returns_this is true), such calls
6427 will appear to have a return value of pointer type
6428 to the low-level call machinery. We do not want to
6429 change the low-level machinery, since we want to be
6430 able to optimize "delete f()" on such platforms as
6431 "operator delete(~X(f()))" (rather than generating
6432 "t = f(), ~X(t), operator delete (t)"). */
6433 call = build_nop (void_type_node, call);
6438 if (processing_template_decl && call != error_mark_node)
6440 bool cast_to_void = false;
6442 if (TREE_CODE (call) == COMPOUND_EXPR)
6443 call = TREE_OPERAND (call, 1);
6444 else if (TREE_CODE (call) == NOP_EXPR)
6446 cast_to_void = true;
6447 call = TREE_OPERAND (call, 0);
6449 if (TREE_CODE (call) == INDIRECT_REF)
6450 call = TREE_OPERAND (call, 0);
6451 call = (build_min_non_dep_call_vec
6453 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6454 orig_instance, orig_fns, NULL_TREE),
6456 call = convert_from_reference (call);
6458 call = build_nop (void_type_node, call);
6461 /* Free all the conversions we allocated. */
6462 obstack_free (&conversion_obstack, p);
6464 if (orig_args != NULL)
6465 release_tree_vector (orig_args);
6470 /* Returns true iff standard conversion sequence ICS1 is a proper
6471 subsequence of ICS2. */
6474 is_subseq (conversion *ics1, conversion *ics2)
6476 /* We can assume that a conversion of the same code
6477 between the same types indicates a subsequence since we only get
6478 here if the types we are converting from are the same. */
6480 while (ics1->kind == ck_rvalue
6481 || ics1->kind == ck_lvalue)
6482 ics1 = ics1->u.next;
6486 while (ics2->kind == ck_rvalue
6487 || ics2->kind == ck_lvalue)
6488 ics2 = ics2->u.next;
6490 if (ics2->kind == ck_user
6491 || ics2->kind == ck_ambig
6492 || ics2->kind == ck_identity)
6493 /* At this point, ICS1 cannot be a proper subsequence of
6494 ICS2. We can get a USER_CONV when we are comparing the
6495 second standard conversion sequence of two user conversion
6499 ics2 = ics2->u.next;
6501 if (ics2->kind == ics1->kind
6502 && same_type_p (ics2->type, ics1->type)
6503 && same_type_p (ics2->u.next->type,
6504 ics1->u.next->type))
6509 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6510 be any _TYPE nodes. */
6513 is_properly_derived_from (tree derived, tree base)
6515 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6518 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6519 considers every class derived from itself. */
6520 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6521 && DERIVED_FROM_P (base, derived));
6524 /* We build the ICS for an implicit object parameter as a pointer
6525 conversion sequence. However, such a sequence should be compared
6526 as if it were a reference conversion sequence. If ICS is the
6527 implicit conversion sequence for an implicit object parameter,
6528 modify it accordingly. */
6531 maybe_handle_implicit_object (conversion **ics)
6535 /* [over.match.funcs]
6537 For non-static member functions, the type of the
6538 implicit object parameter is "reference to cv X"
6539 where X is the class of which the function is a
6540 member and cv is the cv-qualification on the member
6541 function declaration. */
6542 conversion *t = *ics;
6543 tree reference_type;
6545 /* The `this' parameter is a pointer to a class type. Make the
6546 implicit conversion talk about a reference to that same class
6548 reference_type = TREE_TYPE (t->type);
6549 reference_type = build_reference_type (reference_type);
6551 if (t->kind == ck_qual)
6553 if (t->kind == ck_ptr)
6555 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6556 t = direct_reference_binding (reference_type, t);
6558 t->rvaluedness_matches_p = 0;
6563 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6564 and return the initial reference binding conversion. Otherwise,
6565 leave *ICS unchanged and return NULL. */
6568 maybe_handle_ref_bind (conversion **ics)
6570 if ((*ics)->kind == ck_ref_bind)
6572 conversion *old_ics = *ics;
6573 *ics = old_ics->u.next;
6574 (*ics)->user_conv_p = old_ics->user_conv_p;
6581 /* Compare two implicit conversion sequences according to the rules set out in
6582 [over.ics.rank]. Return values:
6584 1: ics1 is better than ics2
6585 -1: ics2 is better than ics1
6586 0: ics1 and ics2 are indistinguishable */
6589 compare_ics (conversion *ics1, conversion *ics2)
6595 tree deref_from_type1 = NULL_TREE;
6596 tree deref_from_type2 = NULL_TREE;
6597 tree deref_to_type1 = NULL_TREE;
6598 tree deref_to_type2 = NULL_TREE;
6599 conversion_rank rank1, rank2;
6601 /* REF_BINDING is nonzero if the result of the conversion sequence
6602 is a reference type. In that case REF_CONV is the reference
6603 binding conversion. */
6604 conversion *ref_conv1;
6605 conversion *ref_conv2;
6607 /* Handle implicit object parameters. */
6608 maybe_handle_implicit_object (&ics1);
6609 maybe_handle_implicit_object (&ics2);
6611 /* Handle reference parameters. */
6612 ref_conv1 = maybe_handle_ref_bind (&ics1);
6613 ref_conv2 = maybe_handle_ref_bind (&ics2);
6615 /* List-initialization sequence L1 is a better conversion sequence than
6616 list-initialization sequence L2 if L1 converts to
6617 std::initializer_list<X> for some X and L2 does not. */
6618 if (ics1->kind == ck_list && ics2->kind != ck_list)
6620 if (ics2->kind == ck_list && ics1->kind != ck_list)
6625 When comparing the basic forms of implicit conversion sequences (as
6626 defined in _over.best.ics_)
6628 --a standard conversion sequence (_over.ics.scs_) is a better
6629 conversion sequence than a user-defined conversion sequence
6630 or an ellipsis conversion sequence, and
6632 --a user-defined conversion sequence (_over.ics.user_) is a
6633 better conversion sequence than an ellipsis conversion sequence
6634 (_over.ics.ellipsis_). */
6635 rank1 = CONVERSION_RANK (ics1);
6636 rank2 = CONVERSION_RANK (ics2);
6640 else if (rank1 < rank2)
6643 if (rank1 == cr_bad)
6645 /* XXX Isn't this an extension? */
6646 /* Both ICS are bad. We try to make a decision based on what
6647 would have happened if they'd been good. */
6648 if (ics1->user_conv_p > ics2->user_conv_p
6649 || ics1->rank > ics2->rank)
6651 else if (ics1->user_conv_p < ics2->user_conv_p
6652 || ics1->rank < ics2->rank)
6655 /* We couldn't make up our minds; try to figure it out below. */
6658 if (ics1->ellipsis_p || ics1->kind == ck_list)
6659 /* Both conversions are ellipsis conversions or both are building a
6660 std::initializer_list. */
6663 /* User-defined conversion sequence U1 is a better conversion sequence
6664 than another user-defined conversion sequence U2 if they contain the
6665 same user-defined conversion operator or constructor and if the sec-
6666 ond standard conversion sequence of U1 is better than the second
6667 standard conversion sequence of U2. */
6669 if (ics1->user_conv_p)
6674 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6675 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6677 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6678 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6681 if (t1->cand->fn != t2->cand->fn)
6684 /* We can just fall through here, after setting up
6685 FROM_TYPE1 and FROM_TYPE2. */
6686 from_type1 = t1->type;
6687 from_type2 = t2->type;
6694 /* We're dealing with two standard conversion sequences.
6698 Standard conversion sequence S1 is a better conversion
6699 sequence than standard conversion sequence S2 if
6701 --S1 is a proper subsequence of S2 (comparing the conversion
6702 sequences in the canonical form defined by _over.ics.scs_,
6703 excluding any Lvalue Transformation; the identity
6704 conversion sequence is considered to be a subsequence of
6705 any non-identity conversion sequence */
6708 while (t1->kind != ck_identity)
6710 from_type1 = t1->type;
6713 while (t2->kind != ck_identity)
6715 from_type2 = t2->type;
6718 /* One sequence can only be a subsequence of the other if they start with
6719 the same type. They can start with different types when comparing the
6720 second standard conversion sequence in two user-defined conversion
6722 if (same_type_p (from_type1, from_type2))
6724 if (is_subseq (ics1, ics2))
6726 if (is_subseq (ics2, ics1))
6734 --the rank of S1 is better than the rank of S2 (by the rules
6737 Standard conversion sequences are ordered by their ranks: an Exact
6738 Match is a better conversion than a Promotion, which is a better
6739 conversion than a Conversion.
6741 Two conversion sequences with the same rank are indistinguishable
6742 unless one of the following rules applies:
6744 --A conversion that is not a conversion of a pointer, or pointer
6745 to member, to bool is better than another conversion that is such
6748 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6749 so that we do not have to check it explicitly. */
6750 if (ics1->rank < ics2->rank)
6752 else if (ics2->rank < ics1->rank)
6755 to_type1 = ics1->type;
6756 to_type2 = ics2->type;
6758 /* A conversion from scalar arithmetic type to complex is worse than a
6759 conversion between scalar arithmetic types. */
6760 if (same_type_p (from_type1, from_type2)
6761 && ARITHMETIC_TYPE_P (from_type1)
6762 && ARITHMETIC_TYPE_P (to_type1)
6763 && ARITHMETIC_TYPE_P (to_type2)
6764 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6765 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6767 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6773 if (TYPE_PTR_P (from_type1)
6774 && TYPE_PTR_P (from_type2)
6775 && TYPE_PTR_P (to_type1)
6776 && TYPE_PTR_P (to_type2))
6778 deref_from_type1 = TREE_TYPE (from_type1);
6779 deref_from_type2 = TREE_TYPE (from_type2);
6780 deref_to_type1 = TREE_TYPE (to_type1);
6781 deref_to_type2 = TREE_TYPE (to_type2);
6783 /* The rules for pointers to members A::* are just like the rules
6784 for pointers A*, except opposite: if B is derived from A then
6785 A::* converts to B::*, not vice versa. For that reason, we
6786 switch the from_ and to_ variables here. */
6787 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6788 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6789 || (TYPE_PTRMEMFUNC_P (from_type1)
6790 && TYPE_PTRMEMFUNC_P (from_type2)
6791 && TYPE_PTRMEMFUNC_P (to_type1)
6792 && TYPE_PTRMEMFUNC_P (to_type2)))
6794 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6795 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6796 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6797 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6800 if (deref_from_type1 != NULL_TREE
6801 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6802 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6804 /* This was one of the pointer or pointer-like conversions.
6808 --If class B is derived directly or indirectly from class A,
6809 conversion of B* to A* is better than conversion of B* to
6810 void*, and conversion of A* to void* is better than
6811 conversion of B* to void*. */
6812 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6813 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6815 if (is_properly_derived_from (deref_from_type1,
6818 else if (is_properly_derived_from (deref_from_type2,
6822 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6823 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6825 if (same_type_p (deref_from_type1, deref_from_type2))
6827 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6829 if (is_properly_derived_from (deref_from_type1,
6833 /* We know that DEREF_TO_TYPE1 is `void' here. */
6834 else if (is_properly_derived_from (deref_from_type1,
6839 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6840 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6844 --If class B is derived directly or indirectly from class A
6845 and class C is derived directly or indirectly from B,
6847 --conversion of C* to B* is better than conversion of C* to
6850 --conversion of B* to A* is better than conversion of C* to
6852 if (same_type_p (deref_from_type1, deref_from_type2))
6854 if (is_properly_derived_from (deref_to_type1,
6857 else if (is_properly_derived_from (deref_to_type2,
6861 else if (same_type_p (deref_to_type1, deref_to_type2))
6863 if (is_properly_derived_from (deref_from_type2,
6866 else if (is_properly_derived_from (deref_from_type1,
6872 else if (CLASS_TYPE_P (non_reference (from_type1))
6873 && same_type_p (from_type1, from_type2))
6875 tree from = non_reference (from_type1);
6879 --binding of an expression of type C to a reference of type
6880 B& is better than binding an expression of type C to a
6881 reference of type A&
6883 --conversion of C to B is better than conversion of C to A, */
6884 if (is_properly_derived_from (from, to_type1)
6885 && is_properly_derived_from (from, to_type2))
6887 if (is_properly_derived_from (to_type1, to_type2))
6889 else if (is_properly_derived_from (to_type2, to_type1))
6893 else if (CLASS_TYPE_P (non_reference (to_type1))
6894 && same_type_p (to_type1, to_type2))
6896 tree to = non_reference (to_type1);
6900 --binding of an expression of type B to a reference of type
6901 A& is better than binding an expression of type C to a
6902 reference of type A&,
6904 --conversion of B to A is better than conversion of C to A */
6905 if (is_properly_derived_from (from_type1, to)
6906 && is_properly_derived_from (from_type2, to))
6908 if (is_properly_derived_from (from_type2, from_type1))
6910 else if (is_properly_derived_from (from_type1, from_type2))
6917 --S1 and S2 differ only in their qualification conversion and yield
6918 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6919 qualification signature of type T1 is a proper subset of the cv-
6920 qualification signature of type T2 */
6921 if (ics1->kind == ck_qual
6922 && ics2->kind == ck_qual
6923 && same_type_p (from_type1, from_type2))
6925 int result = comp_cv_qual_signature (to_type1, to_type2);
6932 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6933 to an implicit object parameter, and either S1 binds an lvalue reference
6934 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6935 reference to an rvalue and S2 binds an lvalue reference
6936 (C++0x draft standard, 13.3.3.2)
6938 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6939 types to which the references refer are the same type except for
6940 top-level cv-qualifiers, and the type to which the reference
6941 initialized by S2 refers is more cv-qualified than the type to
6942 which the reference initialized by S1 refers */
6944 if (ref_conv1 && ref_conv2)
6946 if (!ref_conv1->this_p && !ref_conv2->this_p
6947 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6948 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6950 if (ref_conv1->rvaluedness_matches_p)
6952 if (ref_conv2->rvaluedness_matches_p)
6956 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6957 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6958 TREE_TYPE (ref_conv1->type));
6961 /* Neither conversion sequence is better than the other. */
6965 /* The source type for this standard conversion sequence. */
6968 source_type (conversion *t)
6970 for (;; t = t->u.next)
6972 if (t->kind == ck_user
6973 || t->kind == ck_ambig
6974 || t->kind == ck_identity)
6980 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6981 a pointer to LOSER and re-running joust to produce the warning if WINNER
6982 is actually used. */
6985 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6987 candidate_warning *cw = (candidate_warning *)
6988 conversion_obstack_alloc (sizeof (candidate_warning));
6990 cw->next = winner->warnings;
6991 winner->warnings = cw;
6994 /* Compare two candidates for overloading as described in
6995 [over.match.best]. Return values:
6997 1: cand1 is better than cand2
6998 -1: cand2 is better than cand1
6999 0: cand1 and cand2 are indistinguishable */
7002 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7005 int off1 = 0, off2 = 0;
7009 /* Candidates that involve bad conversions are always worse than those
7011 if (cand1->viable > cand2->viable)
7013 if (cand1->viable < cand2->viable)
7016 /* If we have two pseudo-candidates for conversions to the same type,
7017 or two candidates for the same function, arbitrarily pick one. */
7018 if (cand1->fn == cand2->fn
7019 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7022 /* a viable function F1
7023 is defined to be a better function than another viable function F2 if
7024 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7025 ICSi(F2), and then */
7027 /* for some argument j, ICSj(F1) is a better conversion sequence than
7030 /* For comparing static and non-static member functions, we ignore
7031 the implicit object parameter of the non-static function. The
7032 standard says to pretend that the static function has an object
7033 parm, but that won't work with operator overloading. */
7034 len = cand1->num_convs;
7035 if (len != cand2->num_convs)
7037 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7038 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7040 gcc_assert (static_1 != static_2);
7051 for (i = 0; i < len; ++i)
7053 conversion *t1 = cand1->convs[i + off1];
7054 conversion *t2 = cand2->convs[i + off2];
7055 int comp = compare_ics (t1, t2);
7060 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7061 == cr_std + cr_promotion)
7062 && t1->kind == ck_std
7063 && t2->kind == ck_std
7064 && TREE_CODE (t1->type) == INTEGER_TYPE
7065 && TREE_CODE (t2->type) == INTEGER_TYPE
7066 && (TYPE_PRECISION (t1->type)
7067 == TYPE_PRECISION (t2->type))
7068 && (TYPE_UNSIGNED (t1->u.next->type)
7069 || (TREE_CODE (t1->u.next->type)
7072 tree type = t1->u.next->type;
7074 struct z_candidate *w, *l;
7076 type1 = t1->type, type2 = t2->type,
7077 w = cand1, l = cand2;
7079 type1 = t2->type, type2 = t1->type,
7080 w = cand2, l = cand1;
7084 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7085 type, type1, type2);
7086 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7092 if (winner && comp != winner)
7101 /* warn about confusing overload resolution for user-defined conversions,
7102 either between a constructor and a conversion op, or between two
7104 if (winner && warn_conversion && cand1->second_conv
7105 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7106 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7108 struct z_candidate *w, *l;
7109 bool give_warning = false;
7112 w = cand1, l = cand2;
7114 w = cand2, l = cand1;
7116 /* We don't want to complain about `X::operator T1 ()'
7117 beating `X::operator T2 () const', when T2 is a no less
7118 cv-qualified version of T1. */
7119 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7120 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7122 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7123 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7125 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7130 if (!comp_ptr_ttypes (t, f))
7131 give_warning = true;
7134 give_warning = true;
7140 tree source = source_type (w->convs[0]);
7141 if (! DECL_CONSTRUCTOR_P (w->fn))
7142 source = TREE_TYPE (source);
7143 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7144 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7145 source, w->second_conv->type))
7147 inform (input_location, " because conversion sequence for the argument is better");
7158 F1 is a non-template function and F2 is a template function
7161 if (!cand1->template_decl && cand2->template_decl)
7163 else if (cand1->template_decl && !cand2->template_decl)
7167 F1 and F2 are template functions and the function template for F1 is
7168 more specialized than the template for F2 according to the partial
7171 if (cand1->template_decl && cand2->template_decl)
7173 winner = more_specialized_fn
7174 (TI_TEMPLATE (cand1->template_decl),
7175 TI_TEMPLATE (cand2->template_decl),
7176 /* [temp.func.order]: The presence of unused ellipsis and default
7177 arguments has no effect on the partial ordering of function
7178 templates. add_function_candidate() will not have
7179 counted the "this" argument for constructors. */
7180 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7186 the context is an initialization by user-defined conversion (see
7187 _dcl.init_ and _over.match.user_) and the standard conversion
7188 sequence from the return type of F1 to the destination type (i.e.,
7189 the type of the entity being initialized) is a better conversion
7190 sequence than the standard conversion sequence from the return type
7191 of F2 to the destination type. */
7193 if (cand1->second_conv)
7195 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7200 /* Check whether we can discard a builtin candidate, either because we
7201 have two identical ones or matching builtin and non-builtin candidates.
7203 (Pedantically in the latter case the builtin which matched the user
7204 function should not be added to the overload set, but we spot it here.
7207 ... the builtin candidates include ...
7208 - do not have the same parameter type list as any non-template
7209 non-member candidate. */
7211 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7212 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7214 for (i = 0; i < len; ++i)
7215 if (!same_type_p (cand1->convs[i]->type,
7216 cand2->convs[i]->type))
7218 if (i == cand1->num_convs)
7220 if (cand1->fn == cand2->fn)
7221 /* Two built-in candidates; arbitrarily pick one. */
7223 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7224 /* cand1 is built-in; prefer cand2. */
7227 /* cand2 is built-in; prefer cand1. */
7232 /* If the two function declarations represent the same function (this can
7233 happen with declarations in multiple scopes and arg-dependent lookup),
7234 arbitrarily choose one. But first make sure the default args we're
7236 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7237 && equal_functions (cand1->fn, cand2->fn))
7239 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7240 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7242 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7244 for (i = 0; i < len; ++i)
7246 /* Don't crash if the fn is variadic. */
7249 parms1 = TREE_CHAIN (parms1);
7250 parms2 = TREE_CHAIN (parms2);
7254 parms1 = TREE_CHAIN (parms1);
7256 parms2 = TREE_CHAIN (parms2);
7260 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7261 TREE_PURPOSE (parms2)))
7265 permerror (input_location, "default argument mismatch in "
7266 "overload resolution");
7267 inform (input_location,
7268 " candidate 1: %q+#F", cand1->fn);
7269 inform (input_location,
7270 " candidate 2: %q+#F", cand2->fn);
7273 add_warning (cand1, cand2);
7276 parms1 = TREE_CHAIN (parms1);
7277 parms2 = TREE_CHAIN (parms2);
7285 /* Extension: If the worst conversion for one candidate is worse than the
7286 worst conversion for the other, take the first. */
7289 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7290 struct z_candidate *w = 0, *l = 0;
7292 for (i = 0; i < len; ++i)
7294 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7295 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7296 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7297 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7300 winner = 1, w = cand1, l = cand2;
7302 winner = -1, w = cand2, l = cand1;
7307 pedwarn (input_location, 0,
7308 "ISO C++ says that these are ambiguous, even "
7309 "though the worst conversion for the first is better than "
7310 "the worst conversion for the second:");
7311 print_z_candidate (_("candidate 1:"), w);
7312 print_z_candidate (_("candidate 2:"), l);
7320 gcc_assert (!winner);
7324 /* Given a list of candidates for overloading, find the best one, if any.
7325 This algorithm has a worst case of O(2n) (winner is last), and a best
7326 case of O(n/2) (totally ambiguous); much better than a sorting
7329 static struct z_candidate *
7330 tourney (struct z_candidate *candidates)
7332 struct z_candidate *champ = candidates, *challenger;
7334 int champ_compared_to_predecessor = 0;
7336 /* Walk through the list once, comparing each current champ to the next
7337 candidate, knocking out a candidate or two with each comparison. */
7339 for (challenger = champ->next; challenger; )
7341 fate = joust (champ, challenger, 0);
7343 challenger = challenger->next;
7348 champ = challenger->next;
7351 champ_compared_to_predecessor = 0;
7356 champ_compared_to_predecessor = 1;
7359 challenger = champ->next;
7363 /* Make sure the champ is better than all the candidates it hasn't yet
7364 been compared to. */
7366 for (challenger = candidates;
7368 && !(champ_compared_to_predecessor && challenger->next == champ);
7369 challenger = challenger->next)
7371 fate = joust (champ, challenger, 0);
7379 /* Returns nonzero if things of type FROM can be converted to TO. */
7382 can_convert (tree to, tree from)
7384 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7387 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7390 can_convert_arg (tree to, tree from, tree arg, int flags)
7396 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7397 p = conversion_obstack_alloc (0);
7399 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7401 ok_p = (t && !t->bad_p);
7403 /* Free all the conversions we allocated. */
7404 obstack_free (&conversion_obstack, p);
7409 /* Like can_convert_arg, but allows dubious conversions as well. */
7412 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7417 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7418 p = conversion_obstack_alloc (0);
7419 /* Try to perform the conversion. */
7420 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7422 /* Free all the conversions we allocated. */
7423 obstack_free (&conversion_obstack, p);
7428 /* Convert EXPR to TYPE. Return the converted expression.
7430 Note that we allow bad conversions here because by the time we get to
7431 this point we are committed to doing the conversion. If we end up
7432 doing a bad conversion, convert_like will complain. */
7435 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7440 if (error_operand_p (expr))
7441 return error_mark_node;
7443 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7444 p = conversion_obstack_alloc (0);
7446 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7452 if (complain & tf_error)
7454 /* If expr has unknown type, then it is an overloaded function.
7455 Call instantiate_type to get good error messages. */
7456 if (TREE_TYPE (expr) == unknown_type_node)
7457 instantiate_type (type, expr, complain);
7458 else if (invalid_nonstatic_memfn_p (expr, complain))
7459 /* We gave an error. */;
7461 error ("could not convert %qE to %qT", expr, type);
7463 expr = error_mark_node;
7465 else if (processing_template_decl)
7467 /* In a template, we are only concerned about determining the
7468 type of non-dependent expressions, so we do not have to
7469 perform the actual conversion. */
7470 if (TREE_TYPE (expr) != type)
7471 expr = build_nop (type, expr);
7474 expr = convert_like (conv, expr, complain);
7476 /* Free all the conversions we allocated. */
7477 obstack_free (&conversion_obstack, p);
7483 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7485 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7488 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7489 permitted. If the conversion is valid, the converted expression is
7490 returned. Otherwise, NULL_TREE is returned, except in the case
7491 that TYPE is a class type; in that case, an error is issued. If
7492 C_CAST_P is true, then this direction initialization is taking
7493 place as part of a static_cast being attempted as part of a C-style
7497 perform_direct_initialization_if_possible (tree type,
7500 tsubst_flags_t complain)
7505 if (type == error_mark_node || error_operand_p (expr))
7506 return error_mark_node;
7509 If the destination type is a (possibly cv-qualified) class type:
7511 -- If the initialization is direct-initialization ...,
7512 constructors are considered. ... If no constructor applies, or
7513 the overload resolution is ambiguous, the initialization is
7515 if (CLASS_TYPE_P (type))
7517 VEC(tree,gc) *args = make_tree_vector_single (expr);
7518 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7519 &args, type, LOOKUP_NORMAL, complain);
7520 release_tree_vector (args);
7521 return build_cplus_new (type, expr);
7524 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7525 p = conversion_obstack_alloc (0);
7527 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7530 if (!conv || conv->bad_p)
7533 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7534 /*issue_conversion_warnings=*/false,
7536 tf_warning_or_error);
7538 /* Free all the conversions we allocated. */
7539 obstack_free (&conversion_obstack, p);
7544 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7545 is being bound to a temporary. Create and return a new VAR_DECL
7546 with the indicated TYPE; this variable will store the value to
7547 which the reference is bound. */
7550 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7554 /* Create the variable. */
7555 var = create_temporary_var (type);
7557 /* Register the variable. */
7558 if (TREE_STATIC (decl))
7560 /* Namespace-scope or local static; give it a mangled name. */
7563 TREE_STATIC (var) = 1;
7564 name = mangle_ref_init_variable (decl);
7565 DECL_NAME (var) = name;
7566 SET_DECL_ASSEMBLER_NAME (var, name);
7567 var = pushdecl_top_level (var);
7570 /* Create a new cleanup level if necessary. */
7571 maybe_push_cleanup_level (type);
7576 /* EXPR is the initializer for a variable DECL of reference or
7577 std::initializer_list type. Create, push and return a new VAR_DECL
7578 for the initializer so that it will live as long as DECL. Any
7579 cleanup for the new variable is returned through CLEANUP, and the
7580 code to initialize the new variable is returned through INITP. */
7583 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7589 /* Create the temporary variable. */
7590 type = TREE_TYPE (expr);
7591 var = make_temporary_var_for_ref_to_temp (decl, type);
7592 layout_decl (var, 0);
7593 /* If the rvalue is the result of a function call it will be
7594 a TARGET_EXPR. If it is some other construct (such as a
7595 member access expression where the underlying object is
7596 itself the result of a function call), turn it into a
7597 TARGET_EXPR here. It is important that EXPR be a
7598 TARGET_EXPR below since otherwise the INIT_EXPR will
7599 attempt to make a bitwise copy of EXPR to initialize
7601 if (TREE_CODE (expr) != TARGET_EXPR)
7602 expr = get_target_expr (expr);
7603 /* Create the INIT_EXPR that will initialize the temporary
7605 init = build2 (INIT_EXPR, type, var, expr);
7606 if (at_function_scope_p ())
7608 add_decl_expr (var);
7610 if (TREE_STATIC (var))
7611 init = add_stmt_to_compound (init, register_dtor_fn (var));
7613 *cleanup = cxx_maybe_build_cleanup (var);
7615 /* We must be careful to destroy the temporary only
7616 after its initialization has taken place. If the
7617 initialization throws an exception, then the
7618 destructor should not be run. We cannot simply
7619 transform INIT into something like:
7621 (INIT, ({ CLEANUP_STMT; }))
7623 because emit_local_var always treats the
7624 initializer as a full-expression. Thus, the
7625 destructor would run too early; it would run at the
7626 end of initializing the reference variable, rather
7627 than at the end of the block enclosing the
7630 The solution is to pass back a cleanup expression
7631 which the caller is responsible for attaching to
7632 the statement tree. */
7636 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7637 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7638 static_aggregates = tree_cons (NULL_TREE, var,
7646 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7647 initializing a variable of that TYPE. If DECL is non-NULL, it is
7648 the VAR_DECL being initialized with the EXPR. (In that case, the
7649 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7650 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7651 return, if *CLEANUP is no longer NULL, it will be an expression
7652 that should be pushed as a cleanup after the returned expression
7653 is used to initialize DECL.
7655 Return the converted expression. */
7658 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
7659 tsubst_flags_t complain)
7664 if (type == error_mark_node || error_operand_p (expr))
7665 return error_mark_node;
7667 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7668 p = conversion_obstack_alloc (0);
7670 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7672 if (!conv || conv->bad_p)
7674 if (complain & tf_error)
7676 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7677 && !TYPE_REF_IS_RVALUE (type)
7678 && !real_lvalue_p (expr))
7679 error ("invalid initialization of non-const reference of "
7680 "type %qT from an rvalue of type %qT",
7681 type, TREE_TYPE (expr));
7683 error ("invalid initialization of reference of type "
7684 "%qT from expression of type %qT", type,
7687 return error_mark_node;
7690 /* If DECL is non-NULL, then this special rule applies:
7694 The temporary to which the reference is bound or the temporary
7695 that is the complete object to which the reference is bound
7696 persists for the lifetime of the reference.
7698 The temporaries created during the evaluation of the expression
7699 initializing the reference, except the temporary to which the
7700 reference is bound, are destroyed at the end of the
7701 full-expression in which they are created.
7703 In that case, we store the converted expression into a new
7704 VAR_DECL in a new scope.
7706 However, we want to be careful not to create temporaries when
7707 they are not required. For example, given:
7710 struct D : public B {};
7714 there is no need to copy the return value from "f"; we can just
7715 extend its lifetime. Similarly, given:
7718 struct T { operator S(); };
7722 we can extend the lifetime of the return value of the conversion
7724 gcc_assert (conv->kind == ck_ref_bind);
7728 tree base_conv_type;
7730 /* Skip over the REF_BIND. */
7731 conv = conv->u.next;
7732 /* If the next conversion is a BASE_CONV, skip that too -- but
7733 remember that the conversion was required. */
7734 if (conv->kind == ck_base)
7736 base_conv_type = conv->type;
7737 conv = conv->u.next;
7740 base_conv_type = NULL_TREE;
7741 /* Perform the remainder of the conversion. */
7742 expr = convert_like_real (conv, expr,
7743 /*fn=*/NULL_TREE, /*argnum=*/0,
7745 /*issue_conversion_warnings=*/true,
7747 tf_warning_or_error);
7748 if (error_operand_p (expr))
7749 expr = error_mark_node;
7752 if (!lvalue_or_rvalue_with_address_p (expr))
7755 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7756 /* Use its address to initialize the reference variable. */
7757 expr = build_address (var);
7759 expr = convert_to_base (expr,
7760 build_pointer_type (base_conv_type),
7761 /*check_access=*/true,
7763 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7766 /* Take the address of EXPR. */
7767 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7768 /* If a BASE_CONV was required, perform it now. */
7770 expr = (perform_implicit_conversion
7771 (build_pointer_type (base_conv_type), expr,
7772 tf_warning_or_error));
7773 expr = build_nop (type, expr);
7777 /* Perform the conversion. */
7778 expr = convert_like (conv, expr, tf_warning_or_error);
7780 /* Free all the conversions we allocated. */
7781 obstack_free (&conversion_obstack, p);
7786 /* Returns true iff TYPE is some variant of std::initializer_list. */
7789 is_std_init_list (tree type)
7791 return (CLASS_TYPE_P (type)
7792 && CP_TYPE_CONTEXT (type) == std_node
7793 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7796 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7797 will accept an argument list of a single std::initializer_list<T>. */
7800 is_list_ctor (tree decl)
7802 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7805 if (!args || args == void_list_node)
7808 arg = non_reference (TREE_VALUE (args));
7809 if (!is_std_init_list (arg))
7812 args = TREE_CHAIN (args);
7814 if (args && args != void_list_node && !TREE_PURPOSE (args))
7815 /* There are more non-defaulted parms. */
7821 #include "gt-cp-call.h"