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, 2010
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"
36 #include "diagnostic-core.h"
40 #include "langhooks.h"
42 /* The various kinds of conversion. */
44 typedef enum conversion_kind {
60 /* The rank of the conversion. Order of the enumerals matters; better
61 conversions should come earlier in the list. */
63 typedef enum conversion_rank {
74 /* An implicit conversion sequence, in the sense of [over.best.ics].
75 The first conversion to be performed is at the end of the chain.
76 That conversion is always a cr_identity conversion. */
78 typedef struct conversion conversion;
80 /* The kind of conversion represented by this step. */
82 /* The rank of this conversion. */
84 BOOL_BITFIELD user_conv_p : 1;
85 BOOL_BITFIELD ellipsis_p : 1;
86 BOOL_BITFIELD this_p : 1;
87 BOOL_BITFIELD bad_p : 1;
88 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
89 temporary should be created to hold the result of the
91 BOOL_BITFIELD need_temporary_p : 1;
92 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
93 from a pointer-to-derived to pointer-to-base is being performed. */
94 BOOL_BITFIELD base_p : 1;
95 /* If KIND is ck_ref_bind, true when either an lvalue reference is
96 being bound to an lvalue expression or an rvalue reference is
97 being bound to an rvalue expression. */
98 BOOL_BITFIELD rvaluedness_matches_p: 1;
99 BOOL_BITFIELD check_narrowing: 1;
100 /* The type of the expression resulting from the conversion. */
103 /* The next conversion in the chain. Since the conversions are
104 arranged from outermost to innermost, the NEXT conversion will
105 actually be performed before this conversion. This variant is
106 used only when KIND is neither ck_identity nor ck_ambig. */
108 /* The expression at the beginning of the conversion chain. This
109 variant is used only if KIND is ck_identity or ck_ambig. */
111 /* The array of conversions for an initializer_list. */
114 /* The function candidate corresponding to this conversion
115 sequence. This field is only used if KIND is ck_user. */
116 struct z_candidate *cand;
119 #define CONVERSION_RANK(NODE) \
120 ((NODE)->bad_p ? cr_bad \
121 : (NODE)->ellipsis_p ? cr_ellipsis \
122 : (NODE)->user_conv_p ? cr_user \
125 #define BAD_CONVERSION_RANK(NODE) \
126 ((NODE)->ellipsis_p ? cr_ellipsis \
127 : (NODE)->user_conv_p ? cr_user \
130 static struct obstack conversion_obstack;
131 static bool conversion_obstack_initialized;
133 static struct z_candidate * tourney (struct z_candidate *);
134 static int equal_functions (tree, tree);
135 static int joust (struct z_candidate *, struct z_candidate *, bool);
136 static int compare_ics (conversion *, conversion *);
137 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
138 static tree build_java_interface_fn_ref (tree, tree);
139 #define convert_like(CONV, EXPR, COMPLAIN) \
140 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
141 /*issue_conversion_warnings=*/true, \
142 /*c_cast_p=*/false, (COMPLAIN))
143 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
144 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
145 /*issue_conversion_warnings=*/true, \
146 /*c_cast_p=*/false, (COMPLAIN))
147 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
148 bool, tsubst_flags_t);
149 static void op_error (enum tree_code, enum tree_code, tree, tree,
151 static VEC(tree,gc) *resolve_args (VEC(tree,gc) *);
152 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
153 static void print_z_candidate (const char *, struct z_candidate *);
154 static void print_z_candidates (struct z_candidate *);
155 static tree build_this (tree);
156 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
157 static bool any_strictly_viable (struct z_candidate *);
158 static struct z_candidate *add_template_candidate
159 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
160 tree, tree, tree, int, unification_kind_t);
161 static struct z_candidate *add_template_candidate_real
162 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
163 tree, tree, tree, int, tree, unification_kind_t);
164 static struct z_candidate *add_template_conv_candidate
165 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
167 static void add_builtin_candidates
168 (struct z_candidate **, enum tree_code, enum tree_code,
170 static void add_builtin_candidate
171 (struct z_candidate **, enum tree_code, enum tree_code,
172 tree, tree, tree, tree *, tree *, int);
173 static bool is_complete (tree);
174 static void build_builtin_candidate
175 (struct z_candidate **, tree, tree, tree, tree *, tree *,
177 static struct z_candidate *add_conv_candidate
178 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
180 static struct z_candidate *add_function_candidate
181 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
183 static conversion *implicit_conversion (tree, tree, tree, bool, int);
184 static conversion *standard_conversion (tree, tree, tree, bool, int);
185 static conversion *reference_binding (tree, tree, tree, bool, int);
186 static conversion *build_conv (conversion_kind, tree, conversion *);
187 static conversion *build_list_conv (tree, tree, int);
188 static bool is_subseq (conversion *, conversion *);
189 static conversion *maybe_handle_ref_bind (conversion **);
190 static void maybe_handle_implicit_object (conversion **);
191 static struct z_candidate *add_candidate
192 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
193 conversion **, tree, tree, int);
194 static tree source_type (conversion *);
195 static void add_warning (struct z_candidate *, struct z_candidate *);
196 static bool reference_compatible_p (tree, tree);
197 static conversion *convert_class_to_reference (tree, tree, tree, int);
198 static conversion *direct_reference_binding (tree, conversion *);
199 static bool promoted_arithmetic_type_p (tree);
200 static conversion *conditional_conversion (tree, tree);
201 static char *name_as_c_string (tree, tree, bool *);
202 static tree prep_operand (tree);
203 static void add_candidates (tree, tree, const VEC(tree,gc) *, tree, tree, bool,
204 tree, tree, int, struct z_candidate **);
205 static conversion *merge_conversion_sequences (conversion *, conversion *);
206 static bool magic_varargs_p (tree);
207 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
209 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
210 NAME can take many forms... */
213 check_dtor_name (tree basetype, tree name)
215 /* Just accept something we've already complained about. */
216 if (name == error_mark_node)
219 if (TREE_CODE (name) == TYPE_DECL)
220 name = TREE_TYPE (name);
221 else if (TYPE_P (name))
223 else if (TREE_CODE (name) == IDENTIFIER_NODE)
225 if ((MAYBE_CLASS_TYPE_P (basetype)
226 && name == constructor_name (basetype))
227 || (TREE_CODE (basetype) == ENUMERAL_TYPE
228 && name == TYPE_IDENTIFIER (basetype)))
231 name = get_type_value (name);
237 template <class T> struct S { ~S(); };
241 NAME will be a class template. */
242 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
246 if (!name || name == error_mark_node)
248 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
251 /* We want the address of a function or method. We avoid creating a
252 pointer-to-member function. */
255 build_addr_func (tree function)
257 tree type = TREE_TYPE (function);
259 /* We have to do these by hand to avoid real pointer to member
261 if (TREE_CODE (type) == METHOD_TYPE)
263 if (TREE_CODE (function) == OFFSET_REF)
265 tree object = build_address (TREE_OPERAND (function, 0));
266 return get_member_function_from_ptrfunc (&object,
267 TREE_OPERAND (function, 1));
269 function = build_address (function);
272 function = decay_conversion (function);
277 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
278 POINTER_TYPE to those. Note, pointer to member function types
279 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
280 two variants. build_call_a is the primitive taking an array of
281 arguments, while build_call_n is a wrapper that handles varargs. */
284 build_call_n (tree function, int n, ...)
287 return build_call_a (function, 0, NULL);
290 tree *argarray = XALLOCAVEC (tree, n);
295 for (i = 0; i < n; i++)
296 argarray[i] = va_arg (ap, tree);
298 return build_call_a (function, n, argarray);
303 build_call_a (tree function, int n, tree *argarray)
305 int is_constructor = 0;
312 function = build_addr_func (function);
314 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
315 fntype = TREE_TYPE (TREE_TYPE (function));
316 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
317 || TREE_CODE (fntype) == METHOD_TYPE);
318 result_type = TREE_TYPE (fntype);
319 /* An rvalue has no cv-qualifiers. */
320 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
321 result_type = cv_unqualified (result_type);
323 if (TREE_CODE (function) == ADDR_EXPR
324 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
326 decl = TREE_OPERAND (function, 0);
327 if (!TREE_USED (decl))
329 /* We invoke build_call directly for several library
330 functions. These may have been declared normally if
331 we're building libgcc, so we can't just check
333 gcc_assert (DECL_ARTIFICIAL (decl)
334 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
342 /* We check both the decl and the type; a function may be known not to
343 throw without being declared throw(). */
344 nothrow = ((decl && TREE_NOTHROW (decl))
345 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
347 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
348 current_function_returns_abnormally = 1;
350 if (decl && TREE_DEPRECATED (decl))
351 warn_deprecated_use (decl, NULL_TREE);
352 require_complete_eh_spec_types (fntype, decl);
354 if (decl && DECL_CONSTRUCTOR_P (decl))
357 /* Don't pass empty class objects by value. This is useful
358 for tags in STL, which are used to control overload resolution.
359 We don't need to handle other cases of copying empty classes. */
360 if (! decl || ! DECL_BUILT_IN (decl))
361 for (i = 0; i < n; i++)
362 if (is_empty_class (TREE_TYPE (argarray[i]))
363 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
365 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
366 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
370 function = build_call_array_loc (input_location,
371 result_type, function, n, argarray);
372 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
373 TREE_NOTHROW (function) = nothrow;
378 /* Build something of the form ptr->method (args)
379 or object.method (args). This can also build
380 calls to constructors, and find friends.
382 Member functions always take their class variable
385 INSTANCE is a class instance.
387 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
389 PARMS help to figure out what that NAME really refers to.
391 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
392 down to the real instance type to use for access checking. We need this
393 information to get protected accesses correct.
395 FLAGS is the logical disjunction of zero or more LOOKUP_
396 flags. See cp-tree.h for more info.
398 If this is all OK, calls build_function_call with the resolved
401 This function must also handle being called to perform
402 initialization, promotion/coercion of arguments, and
403 instantiation of default parameters.
405 Note that NAME may refer to an instance variable name. If
406 `operator()()' is defined for the type of that field, then we return
409 /* New overloading code. */
411 typedef struct z_candidate z_candidate;
413 typedef struct candidate_warning candidate_warning;
414 struct candidate_warning {
416 candidate_warning *next;
420 /* The FUNCTION_DECL that will be called if this candidate is
421 selected by overload resolution. */
423 /* If not NULL_TREE, the first argument to use when calling this
426 /* The rest of the arguments to use when calling this function. If
427 there are no further arguments this may be NULL or it may be an
429 const VEC(tree,gc) *args;
430 /* The implicit conversion sequences for each of the arguments to
433 /* The number of implicit conversion sequences. */
435 /* If FN is a user-defined conversion, the standard conversion
436 sequence from the type returned by FN to the desired destination
438 conversion *second_conv;
440 /* If FN is a member function, the binfo indicating the path used to
441 qualify the name of FN at the call site. This path is used to
442 determine whether or not FN is accessible if it is selected by
443 overload resolution. The DECL_CONTEXT of FN will always be a
444 (possibly improper) base of this binfo. */
446 /* If FN is a non-static member function, the binfo indicating the
447 subobject to which the `this' pointer should be converted if FN
448 is selected by overload resolution. The type pointed to the by
449 the `this' pointer must correspond to the most derived class
450 indicated by the CONVERSION_PATH. */
451 tree conversion_path;
454 candidate_warning *warnings;
458 /* Returns true iff T is a null pointer constant in the sense of
462 null_ptr_cst_p (tree t)
466 A null pointer constant is an integral constant expression
467 (_expr.const_) rvalue of integer type that evaluates to zero or
468 an rvalue of type std::nullptr_t. */
469 t = integral_constant_value (t);
471 || NULLPTR_TYPE_P (TREE_TYPE (t)))
473 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
476 if (!TREE_OVERFLOW (t))
482 /* Returns nonzero if PARMLIST consists of only default parms and/or
486 sufficient_parms_p (const_tree parmlist)
488 for (; parmlist && parmlist != void_list_node;
489 parmlist = TREE_CHAIN (parmlist))
490 if (!TREE_PURPOSE (parmlist))
495 /* Allocate N bytes of memory from the conversion obstack. The memory
496 is zeroed before being returned. */
499 conversion_obstack_alloc (size_t n)
502 if (!conversion_obstack_initialized)
504 gcc_obstack_init (&conversion_obstack);
505 conversion_obstack_initialized = true;
507 p = obstack_alloc (&conversion_obstack, n);
512 /* Dynamically allocate a conversion. */
515 alloc_conversion (conversion_kind kind)
518 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
523 #ifdef ENABLE_CHECKING
525 /* Make sure that all memory on the conversion obstack has been
529 validate_conversion_obstack (void)
531 if (conversion_obstack_initialized)
532 gcc_assert ((obstack_next_free (&conversion_obstack)
533 == obstack_base (&conversion_obstack)));
536 #endif /* ENABLE_CHECKING */
538 /* Dynamically allocate an array of N conversions. */
541 alloc_conversions (size_t n)
543 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
547 build_conv (conversion_kind code, tree type, conversion *from)
550 conversion_rank rank = CONVERSION_RANK (from);
552 /* Note that the caller is responsible for filling in t->cand for
553 user-defined conversions. */
554 t = alloc_conversion (code);
577 t->user_conv_p = (code == ck_user || from->user_conv_p);
578 t->bad_p = from->bad_p;
583 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
584 specialization of std::initializer_list<T>, if such a conversion is
588 build_list_conv (tree type, tree ctor, int flags)
590 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
591 unsigned len = CONSTRUCTOR_NELTS (ctor);
592 conversion **subconvs = alloc_conversions (len);
597 /* Within a list-initialization we can have more user-defined
599 flags &= ~LOOKUP_NO_CONVERSION;
600 /* But no narrowing conversions. */
601 flags |= LOOKUP_NO_NARROWING;
603 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
606 = implicit_conversion (elttype, TREE_TYPE (val), val,
614 t = alloc_conversion (ck_list);
616 t->u.list = subconvs;
619 for (i = 0; i < len; ++i)
621 conversion *sub = subconvs[i];
622 if (sub->rank > t->rank)
624 if (sub->user_conv_p)
625 t->user_conv_p = true;
633 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
634 aggregate class, if such a conversion is possible. */
637 build_aggr_conv (tree type, tree ctor, int flags)
639 unsigned HOST_WIDE_INT i = 0;
641 tree field = next_initializable_field (TYPE_FIELDS (type));
642 tree empty_ctor = NULL_TREE;
644 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
646 if (i < CONSTRUCTOR_NELTS (ctor))
648 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
649 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
653 if (TREE_CODE (type) == UNION_TYPE)
658 if (empty_ctor == NULL_TREE)
659 empty_ctor = build_constructor (init_list_type_node, NULL);
660 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (empty_ctor),
666 if (i < CONSTRUCTOR_NELTS (ctor))
669 c = alloc_conversion (ck_aggr);
672 c->user_conv_p = true;
677 /* Build a representation of the identity conversion from EXPR to
678 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
681 build_identity_conv (tree type, tree expr)
685 c = alloc_conversion (ck_identity);
692 /* Converting from EXPR to TYPE was ambiguous in the sense that there
693 were multiple user-defined conversions to accomplish the job.
694 Build a conversion that indicates that ambiguity. */
697 build_ambiguous_conv (tree type, tree expr)
701 c = alloc_conversion (ck_ambig);
709 strip_top_quals (tree t)
711 if (TREE_CODE (t) == ARRAY_TYPE)
713 return cp_build_qualified_type (t, 0);
716 /* Returns the standard conversion path (see [conv]) from type FROM to type
717 TO, if any. For proper handling of null pointer constants, you must
718 also pass the expression EXPR to convert from. If C_CAST_P is true,
719 this conversion is coming from a C-style cast. */
722 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
725 enum tree_code fcode, tcode;
727 bool fromref = false;
729 to = non_reference (to);
730 if (TREE_CODE (from) == REFERENCE_TYPE)
733 from = TREE_TYPE (from);
735 to = strip_top_quals (to);
736 from = strip_top_quals (from);
738 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
739 && expr && type_unknown_p (expr))
741 tsubst_flags_t tflags = tf_conv;
742 if (!(flags & LOOKUP_PROTECT))
743 tflags |= tf_no_access_control;
744 expr = instantiate_type (to, expr, tflags);
745 if (expr == error_mark_node)
747 from = TREE_TYPE (expr);
750 fcode = TREE_CODE (from);
751 tcode = TREE_CODE (to);
753 conv = build_identity_conv (from, expr);
754 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
756 from = type_decays_to (from);
757 fcode = TREE_CODE (from);
758 conv = build_conv (ck_lvalue, from, conv);
760 else if (fromref || (expr && lvalue_p (expr)))
765 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
768 from = strip_top_quals (bitfield_type);
769 fcode = TREE_CODE (from);
772 conv = build_conv (ck_rvalue, from, conv);
775 /* Allow conversion between `__complex__' data types. */
776 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
778 /* The standard conversion sequence to convert FROM to TO is
779 the standard conversion sequence to perform componentwise
781 conversion *part_conv = standard_conversion
782 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
786 conv = build_conv (part_conv->kind, to, conv);
787 conv->rank = part_conv->rank;
795 if (same_type_p (from, to))
799 A null pointer constant can be converted to a pointer type; ... A
800 null pointer constant of integral type can be converted to an
801 rvalue of type std::nullptr_t. */
802 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)
803 || NULLPTR_TYPE_P (to))
804 && expr && null_ptr_cst_p (expr))
805 conv = build_conv (ck_std, to, conv);
806 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
807 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
809 /* For backwards brain damage compatibility, allow interconversion of
810 pointers and integers with a pedwarn. */
811 conv = build_conv (ck_std, to, conv);
814 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
816 /* For backwards brain damage compatibility, allow interconversion of
817 enums and integers with a pedwarn. */
818 conv = build_conv (ck_std, to, conv);
821 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
822 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
827 if (tcode == POINTER_TYPE
828 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
831 else if (VOID_TYPE_P (TREE_TYPE (to))
832 && !TYPE_PTRMEM_P (from)
833 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
835 from = build_pointer_type
836 (cp_build_qualified_type (void_type_node,
837 cp_type_quals (TREE_TYPE (from))));
838 conv = build_conv (ck_ptr, from, conv);
840 else if (TYPE_PTRMEM_P (from))
842 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
843 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
845 if (DERIVED_FROM_P (fbase, tbase)
846 && (same_type_ignoring_top_level_qualifiers_p
847 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
848 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
850 from = build_ptrmem_type (tbase,
851 TYPE_PTRMEM_POINTED_TO_TYPE (from));
852 conv = build_conv (ck_pmem, from, conv);
854 else if (!same_type_p (fbase, tbase))
857 else if (CLASS_TYPE_P (TREE_TYPE (from))
858 && CLASS_TYPE_P (TREE_TYPE (to))
861 An rvalue of type "pointer to cv D," where D is a
862 class type, can be converted to an rvalue of type
863 "pointer to cv B," where B is a base class (clause
864 _class.derived_) of D. If B is an inaccessible
865 (clause _class.access_) or ambiguous
866 (_class.member.lookup_) base class of D, a program
867 that necessitates this conversion is ill-formed.
868 Therefore, we use DERIVED_FROM_P, and do not check
869 access or uniqueness. */
870 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
873 cp_build_qualified_type (TREE_TYPE (to),
874 cp_type_quals (TREE_TYPE (from)));
875 from = build_pointer_type (from);
876 conv = build_conv (ck_ptr, from, conv);
880 if (tcode == POINTER_TYPE)
882 to_pointee = TREE_TYPE (to);
883 from_pointee = TREE_TYPE (from);
887 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
888 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
891 if (same_type_p (from, to))
893 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
894 /* In a C-style cast, we ignore CV-qualification because we
895 are allowed to perform a static_cast followed by a
897 conv = build_conv (ck_qual, to, conv);
898 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
899 conv = build_conv (ck_qual, to, conv);
900 else if (expr && string_conv_p (to, expr, 0))
901 /* converting from string constant to char *. */
902 conv = build_conv (ck_qual, to, conv);
903 /* Allow conversions among compatible ObjC pointer types (base
904 conversions have been already handled above). */
905 else if (c_dialect_objc ()
906 && objc_compare_types (to, from, -4, NULL_TREE))
907 conv = build_conv (ck_ptr, to, conv);
908 else if (ptr_reasonably_similar (to_pointee, from_pointee))
910 conv = build_conv (ck_ptr, to, conv);
918 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
920 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
921 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
922 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
923 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
925 if (!DERIVED_FROM_P (fbase, tbase)
926 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
927 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
928 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
929 || cp_type_quals (fbase) != cp_type_quals (tbase))
932 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
933 from = build_ptrmemfunc_type (build_pointer_type (from));
934 conv = build_conv (ck_pmem, from, conv);
937 else if (tcode == BOOLEAN_TYPE)
941 An rvalue of arithmetic, unscoped enumeration, pointer, or
942 pointer to member type can be converted to an rvalue of type
943 bool. ... An rvalue of type std::nullptr_t can be converted
944 to an rvalue of type bool; */
945 if (ARITHMETIC_TYPE_P (from)
946 || UNSCOPED_ENUM_P (from)
947 || fcode == POINTER_TYPE
948 || TYPE_PTR_TO_MEMBER_P (from)
949 || NULLPTR_TYPE_P (from))
951 conv = build_conv (ck_std, to, conv);
952 if (fcode == POINTER_TYPE
953 || TYPE_PTRMEM_P (from)
954 || (TYPE_PTRMEMFUNC_P (from)
955 && conv->rank < cr_pbool)
956 || NULLPTR_TYPE_P (from))
957 conv->rank = cr_pbool;
963 /* We don't check for ENUMERAL_TYPE here because there are no standard
964 conversions to enum type. */
965 /* As an extension, allow conversion to complex type. */
966 else if (ARITHMETIC_TYPE_P (to))
968 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
969 || SCOPED_ENUM_P (from))
971 conv = build_conv (ck_std, to, conv);
973 /* Give this a better rank if it's a promotion. */
974 if (same_type_p (to, type_promotes_to (from))
975 && conv->u.next->rank <= cr_promotion)
976 conv->rank = cr_promotion;
978 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
979 && vector_types_convertible_p (from, to, false))
980 return build_conv (ck_std, to, conv);
981 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
982 && is_properly_derived_from (from, to))
984 if (conv->kind == ck_rvalue)
986 conv = build_conv (ck_base, to, conv);
987 /* The derived-to-base conversion indicates the initialization
988 of a parameter with base type from an object of a derived
989 type. A temporary object is created to hold the result of
990 the conversion unless we're binding directly to a reference. */
991 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
996 if (flags & LOOKUP_NO_NARROWING)
997 conv->check_narrowing = true;
1002 /* Returns nonzero if T1 is reference-related to T2. */
1005 reference_related_p (tree t1, tree t2)
1007 if (t1 == error_mark_node || t2 == error_mark_node)
1010 t1 = TYPE_MAIN_VARIANT (t1);
1011 t2 = TYPE_MAIN_VARIANT (t2);
1015 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1016 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1018 return (same_type_p (t1, t2)
1019 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1020 && DERIVED_FROM_P (t1, t2)));
1023 /* Returns nonzero if T1 is reference-compatible with T2. */
1026 reference_compatible_p (tree t1, tree t2)
1030 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1031 reference-related to T2 and cv1 is the same cv-qualification as,
1032 or greater cv-qualification than, cv2. */
1033 return (reference_related_p (t1, t2)
1034 && at_least_as_qualified_p (t1, t2));
1037 /* Determine whether or not the EXPR (of class type S) can be
1038 converted to T as in [over.match.ref]. */
1041 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1047 struct z_candidate *candidates;
1048 struct z_candidate *cand;
1054 conversions = lookup_conversions (s, /*lookup_template_convs_p=*/true);
1060 Assuming that "cv1 T" is the underlying type of the reference
1061 being initialized, and "cv S" is the type of the initializer
1062 expression, with S a class type, the candidate functions are
1063 selected as follows:
1065 --The conversion functions of S and its base classes are
1066 considered. Those that are not hidden within S and yield type
1067 "reference to cv2 T2", where "cv1 T" is reference-compatible
1068 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1070 The argument list has one argument, which is the initializer
1075 /* Conceptually, we should take the address of EXPR and put it in
1076 the argument list. Unfortunately, however, that can result in
1077 error messages, which we should not issue now because we are just
1078 trying to find a conversion operator. Therefore, we use NULL,
1079 cast to the appropriate type. */
1080 first_arg = build_int_cst (build_pointer_type (s), 0);
1082 t = TREE_TYPE (reference_type);
1084 /* We're performing a user-defined conversion to a desired type, so set
1085 this for the benefit of add_candidates. */
1086 flags |= LOOKUP_NO_CONVERSION;
1088 for (; conversions; conversions = TREE_CHAIN (conversions))
1090 tree fns = TREE_VALUE (conversions);
1091 tree binfo = TREE_PURPOSE (conversions);
1092 struct z_candidate *old_candidates = candidates;;
1094 add_candidates (fns, first_arg, NULL, reference_type,
1096 binfo, TYPE_BINFO (s),
1097 flags, &candidates);
1099 for (cand = candidates; cand != old_candidates; cand = cand->next)
1101 /* Now, see if the conversion function really returns
1102 an lvalue of the appropriate type. From the
1103 point of view of unification, simply returning an
1104 rvalue of the right type is good enough. */
1106 tree t2 = TREE_TYPE (TREE_TYPE (f));
1107 if (TREE_CODE (t2) != REFERENCE_TYPE
1108 || !reference_compatible_p (t, TREE_TYPE (t2)))
1114 conversion *identity_conv;
1115 /* Build a standard conversion sequence indicating the
1116 binding from the reference type returned by the
1117 function to the desired REFERENCE_TYPE. */
1119 = build_identity_conv (TREE_TYPE (TREE_TYPE
1120 (TREE_TYPE (cand->fn))),
1123 = (direct_reference_binding
1124 (reference_type, identity_conv));
1125 cand->second_conv->rvaluedness_matches_p
1126 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1127 == TYPE_REF_IS_RVALUE (reference_type);
1128 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1130 /* Don't allow binding of lvalues to rvalue references. */
1131 if (TYPE_REF_IS_RVALUE (reference_type)
1132 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1133 cand->second_conv->bad_p = true;
1138 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1139 /* If none of the conversion functions worked out, let our caller
1144 cand = tourney (candidates);
1148 /* Now that we know that this is the function we're going to use fix
1149 the dummy first argument. */
1150 gcc_assert (cand->first_arg == NULL_TREE
1151 || integer_zerop (cand->first_arg));
1152 cand->first_arg = build_this (expr);
1154 /* Build a user-defined conversion sequence representing the
1156 conv = build_conv (ck_user,
1157 TREE_TYPE (TREE_TYPE (cand->fn)),
1158 build_identity_conv (TREE_TYPE (expr), expr));
1161 if (cand->viable == -1)
1164 /* Merge it with the standard conversion sequence from the
1165 conversion function's return type to the desired type. */
1166 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1168 return cand->second_conv;
1171 /* A reference of the indicated TYPE is being bound directly to the
1172 expression represented by the implicit conversion sequence CONV.
1173 Return a conversion sequence for this binding. */
1176 direct_reference_binding (tree type, conversion *conv)
1180 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1181 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1183 t = TREE_TYPE (type);
1187 When a parameter of reference type binds directly
1188 (_dcl.init.ref_) to an argument expression, the implicit
1189 conversion sequence is the identity conversion, unless the
1190 argument expression has a type that is a derived class of the
1191 parameter type, in which case the implicit conversion sequence is
1192 a derived-to-base Conversion.
1194 If the parameter binds directly to the result of applying a
1195 conversion function to the argument expression, the implicit
1196 conversion sequence is a user-defined conversion sequence
1197 (_over.ics.user_), with the second standard conversion sequence
1198 either an identity conversion or, if the conversion function
1199 returns an entity of a type that is a derived class of the
1200 parameter type, a derived-to-base conversion. */
1201 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1203 /* Represent the derived-to-base conversion. */
1204 conv = build_conv (ck_base, t, conv);
1205 /* We will actually be binding to the base-class subobject in
1206 the derived class, so we mark this conversion appropriately.
1207 That way, convert_like knows not to generate a temporary. */
1208 conv->need_temporary_p = false;
1210 return build_conv (ck_ref_bind, type, conv);
1213 /* Returns the conversion path from type FROM to reference type TO for
1214 purposes of reference binding. For lvalue binding, either pass a
1215 reference type to FROM or an lvalue expression to EXPR. If the
1216 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1217 the conversion returned. If C_CAST_P is true, this
1218 conversion is coming from a C-style cast. */
1221 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1223 conversion *conv = NULL;
1224 tree to = TREE_TYPE (rto);
1229 cp_lvalue_kind is_lvalue = clk_none;
1231 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1233 expr = instantiate_type (to, expr, tf_none);
1234 if (expr == error_mark_node)
1236 from = TREE_TYPE (expr);
1239 if (TREE_CODE (from) == REFERENCE_TYPE)
1241 /* Anything with reference type is an lvalue. */
1242 is_lvalue = clk_ordinary;
1243 from = TREE_TYPE (from);
1246 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1248 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1249 conv = implicit_conversion (to, from, expr, c_cast_p,
1251 if (!CLASS_TYPE_P (to)
1252 && CONSTRUCTOR_NELTS (expr) == 1)
1254 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1255 if (error_operand_p (expr))
1257 from = TREE_TYPE (expr);
1261 if (is_lvalue == clk_none && expr)
1262 is_lvalue = real_lvalue_p (expr);
1265 if ((is_lvalue & clk_bitfield) != 0)
1266 tfrom = unlowered_expr_type (expr);
1268 /* Figure out whether or not the types are reference-related and
1269 reference compatible. We have do do this after stripping
1270 references from FROM. */
1271 related_p = reference_related_p (to, tfrom);
1272 /* If this is a C cast, first convert to an appropriately qualified
1273 type, so that we can later do a const_cast to the desired type. */
1274 if (related_p && c_cast_p
1275 && !at_least_as_qualified_p (to, tfrom))
1276 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1277 compatible_p = reference_compatible_p (to, tfrom);
1279 /* Directly bind reference when target expression's type is compatible with
1280 the reference and expression is an lvalue. In DR391, the wording in
1281 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1282 const and rvalue references to rvalues of compatible class type.
1283 We should also do direct bindings for non-class "rvalues" derived from
1284 rvalue references. */
1287 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1288 && !(flags & LOOKUP_NO_TEMP_BIND))
1289 || TYPE_REF_IS_RVALUE (rto))
1290 && (CLASS_TYPE_P (from) || (expr && lvalue_p (expr))))))
1294 If the initializer expression
1296 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1297 is reference-compatible with "cv2 T2,"
1299 the reference is bound directly to the initializer expression
1303 If the initializer expression is an rvalue, with T2 a class type,
1304 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1305 is bound to the object represented by the rvalue or to a sub-object
1306 within that object. */
1308 conv = build_identity_conv (tfrom, expr);
1309 conv = direct_reference_binding (rto, conv);
1311 if (flags & LOOKUP_PREFER_RVALUE)
1312 /* The top-level caller requested that we pretend that the lvalue
1313 be treated as an rvalue. */
1314 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1316 conv->rvaluedness_matches_p
1317 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1319 if ((is_lvalue & clk_bitfield) != 0
1320 || ((is_lvalue & clk_packed) != 0 && !TYPE_PACKED (to)))
1321 /* For the purposes of overload resolution, we ignore the fact
1322 this expression is a bitfield or packed field. (In particular,
1323 [over.ics.ref] says specifically that a function with a
1324 non-const reference parameter is viable even if the
1325 argument is a bitfield.)
1327 However, when we actually call the function we must create
1328 a temporary to which to bind the reference. If the
1329 reference is volatile, or isn't const, then we cannot make
1330 a temporary, so we just issue an error when the conversion
1332 conv->need_temporary_p = true;
1334 /* Don't allow binding of lvalues to rvalue references. */
1335 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1336 && !(flags & LOOKUP_PREFER_RVALUE))
1341 /* [class.conv.fct] A conversion function is never used to convert a
1342 (possibly cv-qualified) object to the (possibly cv-qualified) same
1343 object type (or a reference to it), to a (possibly cv-qualified) base
1344 class of that type (or a reference to it).... */
1345 else if (CLASS_TYPE_P (from) && !related_p
1346 && !(flags & LOOKUP_NO_CONVERSION))
1350 If the initializer expression
1352 -- has a class type (i.e., T2 is a class type) can be
1353 implicitly converted to an lvalue of type "cv3 T3," where
1354 "cv1 T1" is reference-compatible with "cv3 T3". (this
1355 conversion is selected by enumerating the applicable
1356 conversion functions (_over.match.ref_) and choosing the
1357 best one through overload resolution. (_over.match_).
1359 the reference is bound to the lvalue result of the conversion
1360 in the second case. */
1361 conv = convert_class_to_reference (rto, from, expr, flags);
1366 /* From this point on, we conceptually need temporaries, even if we
1367 elide them. Only the cases above are "direct bindings". */
1368 if (flags & LOOKUP_NO_TEMP_BIND)
1373 When a parameter of reference type is not bound directly to an
1374 argument expression, the conversion sequence is the one required
1375 to convert the argument expression to the underlying type of the
1376 reference according to _over.best.ics_. Conceptually, this
1377 conversion sequence corresponds to copy-initializing a temporary
1378 of the underlying type with the argument expression. Any
1379 difference in top-level cv-qualification is subsumed by the
1380 initialization itself and does not constitute a conversion. */
1384 Otherwise, the reference shall be to a non-volatile const type.
1386 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1387 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1392 Otherwise, a temporary of type "cv1 T1" is created and
1393 initialized from the initializer expression using the rules for a
1394 non-reference copy initialization. If T1 is reference-related to
1395 T2, cv1 must be the same cv-qualification as, or greater
1396 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1397 if (related_p && !at_least_as_qualified_p (to, from))
1400 /* We're generating a temporary now, but don't bind any more in the
1401 conversion (specifically, don't slice the temporary returned by a
1402 conversion operator). */
1403 flags |= LOOKUP_NO_TEMP_BIND;
1405 /* Core issue 899: When [copy-]initializing a temporary to be bound
1406 to the first parameter of a copy constructor (12.8) called with
1407 a single argument in the context of direct-initialization,
1408 explicit conversion functions are also considered.
1410 So don't set LOOKUP_ONLYCONVERTING in that case. */
1411 if (!(flags & LOOKUP_COPY_PARM))
1412 flags |= LOOKUP_ONLYCONVERTING;
1415 conv = implicit_conversion (to, from, expr, c_cast_p,
1420 conv = build_conv (ck_ref_bind, rto, conv);
1421 /* This reference binding, unlike those above, requires the
1422 creation of a temporary. */
1423 conv->need_temporary_p = true;
1424 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1429 /* Returns the implicit conversion sequence (see [over.ics]) from type
1430 FROM to type TO. The optional expression EXPR may affect the
1431 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1432 true, this conversion is coming from a C-style cast. */
1435 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1440 if (from == error_mark_node || to == error_mark_node
1441 || expr == error_mark_node)
1444 if (TREE_CODE (to) == REFERENCE_TYPE)
1445 conv = reference_binding (to, from, expr, c_cast_p, flags);
1447 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1452 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1454 if (is_std_init_list (to))
1455 return build_list_conv (to, expr, flags);
1457 /* Allow conversion from an initializer-list with one element to a
1459 if (SCALAR_TYPE_P (to))
1461 int nelts = CONSTRUCTOR_NELTS (expr);
1465 elt = build_value_init (to, tf_none);
1466 else if (nelts == 1)
1467 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1469 elt = error_mark_node;
1471 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1475 conv->check_narrowing = true;
1476 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1477 /* Too many levels of braces, i.e. '{{1}}'. */
1484 if (expr != NULL_TREE
1485 && (MAYBE_CLASS_TYPE_P (from)
1486 || MAYBE_CLASS_TYPE_P (to))
1487 && (flags & LOOKUP_NO_CONVERSION) == 0)
1489 struct z_candidate *cand;
1490 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING
1491 |LOOKUP_NO_NARROWING));
1493 if (CLASS_TYPE_P (to)
1494 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1495 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1496 return build_aggr_conv (to, expr, flags);
1498 cand = build_user_type_conversion_1 (to, expr, convflags);
1500 conv = cand->second_conv;
1502 /* We used to try to bind a reference to a temporary here, but that
1503 is now handled after the recursive call to this function at the end
1504 of reference_binding. */
1511 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1512 functions. ARGS will not be changed until a single candidate is
1515 static struct z_candidate *
1516 add_candidate (struct z_candidate **candidates,
1517 tree fn, tree first_arg, const VEC(tree,gc) *args,
1518 size_t num_convs, conversion **convs,
1519 tree access_path, tree conversion_path,
1522 struct z_candidate *cand = (struct z_candidate *)
1523 conversion_obstack_alloc (sizeof (struct z_candidate));
1526 cand->first_arg = first_arg;
1528 cand->convs = convs;
1529 cand->num_convs = num_convs;
1530 cand->access_path = access_path;
1531 cand->conversion_path = conversion_path;
1532 cand->viable = viable;
1533 cand->next = *candidates;
1539 /* Create an overload candidate for the function or method FN called
1540 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1541 FLAGS is passed on to implicit_conversion.
1543 This does not change ARGS.
1545 CTYPE, if non-NULL, is the type we want to pretend this function
1546 comes from for purposes of overload resolution. */
1548 static struct z_candidate *
1549 add_function_candidate (struct z_candidate **candidates,
1550 tree fn, tree ctype, tree first_arg,
1551 const VEC(tree,gc) *args, tree access_path,
1552 tree conversion_path, int flags)
1554 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1558 tree orig_first_arg = first_arg;
1562 /* At this point we should not see any functions which haven't been
1563 explicitly declared, except for friend functions which will have
1564 been found using argument dependent lookup. */
1565 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1567 /* The `this', `in_chrg' and VTT arguments to constructors are not
1568 considered in overload resolution. */
1569 if (DECL_CONSTRUCTOR_P (fn))
1571 parmlist = skip_artificial_parms_for (fn, parmlist);
1572 skip = num_artificial_parms_for (fn);
1573 if (skip > 0 && first_arg != NULL_TREE)
1576 first_arg = NULL_TREE;
1582 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1583 convs = alloc_conversions (len);
1585 /* 13.3.2 - Viable functions [over.match.viable]
1586 First, to be a viable function, a candidate function shall have enough
1587 parameters to agree in number with the arguments in the list.
1589 We need to check this first; otherwise, checking the ICSes might cause
1590 us to produce an ill-formed template instantiation. */
1592 parmnode = parmlist;
1593 for (i = 0; i < len; ++i)
1595 if (parmnode == NULL_TREE || parmnode == void_list_node)
1597 parmnode = TREE_CHAIN (parmnode);
1600 if (i < len && parmnode)
1603 /* Make sure there are default args for the rest of the parms. */
1604 else if (!sufficient_parms_p (parmnode))
1607 /* Kludge: When looking for a function from a subobject while generating
1608 an implicit copy/move constructor/operator=, don't consider anything
1609 that takes (a reference to) an unrelated type. See c++/44909. */
1610 else if ((flags & LOOKUP_SPECULATIVE)
1611 || (current_function_decl
1612 && DECL_DEFAULTED_FN (current_function_decl)))
1614 if (DECL_CONSTRUCTOR_P (fn))
1616 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1617 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
1623 parmnode = chain_index (i-1, parmlist);
1624 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
1633 /* Second, for F to be a viable function, there shall exist for each
1634 argument an implicit conversion sequence that converts that argument
1635 to the corresponding parameter of F. */
1637 parmnode = parmlist;
1639 for (i = 0; i < len; ++i)
1645 if (parmnode == void_list_node)
1648 if (i == 0 && first_arg != NULL_TREE)
1651 arg = VEC_index (tree, args,
1652 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1653 argtype = lvalue_type (arg);
1655 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1656 && ! DECL_CONSTRUCTOR_P (fn));
1660 tree parmtype = TREE_VALUE (parmnode);
1663 parmnode = TREE_CHAIN (parmnode);
1665 /* The type of the implicit object parameter ('this') for
1666 overload resolution is not always the same as for the
1667 function itself; conversion functions are considered to
1668 be members of the class being converted, and functions
1669 introduced by a using-declaration are considered to be
1670 members of the class that uses them.
1672 Since build_over_call ignores the ICS for the `this'
1673 parameter, we can just change the parm type. */
1674 if (ctype && is_this)
1676 parmtype = cp_build_qualified_type
1677 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
1678 parmtype = build_pointer_type (parmtype);
1681 /* Core issue 899: When [copy-]initializing a temporary to be bound
1682 to the first parameter of a copy constructor (12.8) called with
1683 a single argument in the context of direct-initialization,
1684 explicit conversion functions are also considered.
1686 So set LOOKUP_COPY_PARM to let reference_binding know that
1687 it's being called in that context. We generalize the above
1688 to handle move constructors and template constructors as well;
1689 the standardese should soon be updated similarly. */
1690 if (ctype && i == 0 && (len-skip == 1)
1691 && !(flags & LOOKUP_ONLYCONVERTING)
1692 && DECL_CONSTRUCTOR_P (fn)
1693 && parmtype != error_mark_node
1694 && (same_type_ignoring_top_level_qualifiers_p
1695 (non_reference (parmtype), ctype)))
1697 lflags |= LOOKUP_COPY_PARM;
1698 /* We allow user-defined conversions within init-lists, but
1699 not for the copy constructor. */
1700 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1701 lflags |= LOOKUP_NO_CONVERSION;
1704 lflags |= LOOKUP_ONLYCONVERTING;
1706 t = implicit_conversion (parmtype, argtype, arg,
1707 /*c_cast_p=*/false, lflags);
1711 t = build_identity_conv (argtype, arg);
1712 t->ellipsis_p = true;
1730 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1731 access_path, conversion_path, viable);
1734 /* Create an overload candidate for the conversion function FN which will
1735 be invoked for expression OBJ, producing a pointer-to-function which
1736 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1737 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1738 passed on to implicit_conversion.
1740 Actually, we don't really care about FN; we care about the type it
1741 converts to. There may be multiple conversion functions that will
1742 convert to that type, and we rely on build_user_type_conversion_1 to
1743 choose the best one; so when we create our candidate, we record the type
1744 instead of the function. */
1746 static struct z_candidate *
1747 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1748 tree first_arg, const VEC(tree,gc) *arglist,
1749 tree access_path, tree conversion_path)
1751 tree totype = TREE_TYPE (TREE_TYPE (fn));
1752 int i, len, viable, flags;
1753 tree parmlist, parmnode;
1756 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1757 parmlist = TREE_TYPE (parmlist);
1758 parmlist = TYPE_ARG_TYPES (parmlist);
1760 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1761 convs = alloc_conversions (len);
1762 parmnode = parmlist;
1764 flags = LOOKUP_IMPLICIT;
1766 /* Don't bother looking up the same type twice. */
1767 if (*candidates && (*candidates)->fn == totype)
1770 for (i = 0; i < len; ++i)
1777 else if (i == 1 && first_arg != NULL_TREE)
1780 arg = VEC_index (tree, arglist,
1781 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1782 argtype = lvalue_type (arg);
1785 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1787 else if (parmnode == void_list_node)
1790 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1791 /*c_cast_p=*/false, flags);
1794 t = build_identity_conv (argtype, arg);
1795 t->ellipsis_p = true;
1809 parmnode = TREE_CHAIN (parmnode);
1815 if (!sufficient_parms_p (parmnode))
1818 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1819 access_path, conversion_path, viable);
1823 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1824 tree type1, tree type2, tree *args, tree *argtypes,
1836 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1837 convs = alloc_conversions (num_convs);
1839 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
1840 conversion ops are allowed. We handle that here by just checking for
1841 boolean_type_node because other operators don't ask for it. COND_EXPR
1842 also does contextual conversion to bool for the first operand, but we
1843 handle that in build_conditional_expr, and type1 here is operand 2. */
1844 if (type1 != boolean_type_node)
1845 flags |= LOOKUP_ONLYCONVERTING;
1847 for (i = 0; i < 2; ++i)
1852 t = implicit_conversion (types[i], argtypes[i], args[i],
1853 /*c_cast_p=*/false, flags);
1857 /* We need something for printing the candidate. */
1858 t = build_identity_conv (types[i], NULL_TREE);
1865 /* For COND_EXPR we rearranged the arguments; undo that now. */
1868 convs[2] = convs[1];
1869 convs[1] = convs[0];
1870 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1871 /*c_cast_p=*/false, flags);
1878 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1880 /*access_path=*/NULL_TREE,
1881 /*conversion_path=*/NULL_TREE,
1886 is_complete (tree t)
1888 return COMPLETE_TYPE_P (complete_type (t));
1891 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1894 promoted_arithmetic_type_p (tree type)
1898 In this section, the term promoted integral type is used to refer
1899 to those integral types which are preserved by integral promotion
1900 (including e.g. int and long but excluding e.g. char).
1901 Similarly, the term promoted arithmetic type refers to promoted
1902 integral types plus floating types. */
1903 return ((CP_INTEGRAL_TYPE_P (type)
1904 && same_type_p (type_promotes_to (type), type))
1905 || TREE_CODE (type) == REAL_TYPE);
1908 /* Create any builtin operator overload candidates for the operator in
1909 question given the converted operand types TYPE1 and TYPE2. The other
1910 args are passed through from add_builtin_candidates to
1911 build_builtin_candidate.
1913 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1914 If CODE is requires candidates operands of the same type of the kind
1915 of which TYPE1 and TYPE2 are, we add both candidates
1916 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1919 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1920 enum tree_code code2, tree fnname, tree type1,
1921 tree type2, tree *args, tree *argtypes, int flags)
1925 case POSTINCREMENT_EXPR:
1926 case POSTDECREMENT_EXPR:
1927 args[1] = integer_zero_node;
1928 type2 = integer_type_node;
1937 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1938 and VQ is either volatile or empty, there exist candidate operator
1939 functions of the form
1940 VQ T& operator++(VQ T&);
1941 T operator++(VQ T&, int);
1942 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1943 type other than bool, and VQ is either volatile or empty, there exist
1944 candidate operator functions of the form
1945 VQ T& operator--(VQ T&);
1946 T operator--(VQ T&, int);
1947 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1948 complete object type, and VQ is either volatile or empty, there exist
1949 candidate operator functions of the form
1950 T*VQ& operator++(T*VQ&);
1951 T*VQ& operator--(T*VQ&);
1952 T* operator++(T*VQ&, int);
1953 T* operator--(T*VQ&, int); */
1955 case POSTDECREMENT_EXPR:
1956 case PREDECREMENT_EXPR:
1957 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1959 case POSTINCREMENT_EXPR:
1960 case PREINCREMENT_EXPR:
1961 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1963 type1 = build_reference_type (type1);
1968 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1969 exist candidate operator functions of the form
1973 8 For every function type T, there exist candidate operator functions of
1975 T& operator*(T*); */
1978 if (TREE_CODE (type1) == POINTER_TYPE
1979 && (TYPE_PTROB_P (type1)
1980 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1984 /* 9 For every type T, there exist candidate operator functions of the form
1987 10For every promoted arithmetic type T, there exist candidate operator
1988 functions of the form
1992 case UNARY_PLUS_EXPR: /* unary + */
1993 if (TREE_CODE (type1) == POINTER_TYPE)
1996 if (ARITHMETIC_TYPE_P (type1))
2000 /* 11For every promoted integral type T, there exist candidate operator
2001 functions of the form
2005 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2009 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2010 is the same type as C2 or is a derived class of C2, T is a complete
2011 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2012 there exist candidate operator functions of the form
2013 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2014 where CV12 is the union of CV1 and CV2. */
2017 if (TREE_CODE (type1) == POINTER_TYPE
2018 && TYPE_PTR_TO_MEMBER_P (type2))
2020 tree c1 = TREE_TYPE (type1);
2021 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2023 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2024 && (TYPE_PTRMEMFUNC_P (type2)
2025 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2030 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2031 didate operator functions of the form
2036 bool operator<(L, R);
2037 bool operator>(L, R);
2038 bool operator<=(L, R);
2039 bool operator>=(L, R);
2040 bool operator==(L, R);
2041 bool operator!=(L, R);
2042 where LR is the result of the usual arithmetic conversions between
2045 14For every pair of types T and I, where T is a cv-qualified or cv-
2046 unqualified complete object type and I is a promoted integral type,
2047 there exist candidate operator functions of the form
2048 T* operator+(T*, I);
2049 T& operator[](T*, I);
2050 T* operator-(T*, I);
2051 T* operator+(I, T*);
2052 T& operator[](I, T*);
2054 15For every T, where T is a pointer to complete object type, there exist
2055 candidate operator functions of the form112)
2056 ptrdiff_t operator-(T, T);
2058 16For every pointer or enumeration type T, there exist candidate operator
2059 functions of the form
2060 bool operator<(T, T);
2061 bool operator>(T, T);
2062 bool operator<=(T, T);
2063 bool operator>=(T, T);
2064 bool operator==(T, T);
2065 bool operator!=(T, T);
2067 17For every pointer to member type T, there exist candidate operator
2068 functions of the form
2069 bool operator==(T, T);
2070 bool operator!=(T, T); */
2073 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2075 if (TYPE_PTROB_P (type1)
2076 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2078 type2 = ptrdiff_type_node;
2082 case TRUNC_DIV_EXPR:
2083 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2089 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2090 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2092 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2097 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2109 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2111 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2113 if (TREE_CODE (type1) == ENUMERAL_TYPE
2114 && TREE_CODE (type2) == ENUMERAL_TYPE)
2116 if (TYPE_PTR_P (type1)
2117 && null_ptr_cst_p (args[1])
2118 && !uses_template_parms (type1))
2123 if (null_ptr_cst_p (args[0])
2124 && TYPE_PTR_P (type2)
2125 && !uses_template_parms (type2))
2133 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2136 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2138 type1 = ptrdiff_type_node;
2141 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2143 type2 = ptrdiff_type_node;
2148 /* 18For every pair of promoted integral types L and R, there exist candi-
2149 date operator functions of the form
2156 where LR is the result of the usual arithmetic conversions between
2159 case TRUNC_MOD_EXPR:
2165 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2169 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2170 type, VQ is either volatile or empty, and R is a promoted arithmetic
2171 type, there exist candidate operator functions of the form
2172 VQ L& operator=(VQ L&, R);
2173 VQ L& operator*=(VQ L&, R);
2174 VQ L& operator/=(VQ L&, R);
2175 VQ L& operator+=(VQ L&, R);
2176 VQ L& operator-=(VQ L&, R);
2178 20For every pair T, VQ), where T is any type and VQ is either volatile
2179 or empty, there exist candidate operator functions of the form
2180 T*VQ& operator=(T*VQ&, T*);
2182 21For every pair T, VQ), where T is a pointer to member type and VQ is
2183 either volatile or empty, there exist candidate operator functions of
2185 VQ T& operator=(VQ T&, T);
2187 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2188 unqualified complete object type, VQ is either volatile or empty, and
2189 I is a promoted integral type, there exist candidate operator func-
2191 T*VQ& operator+=(T*VQ&, I);
2192 T*VQ& operator-=(T*VQ&, I);
2194 23For every triple L, VQ, R), where L is an integral or enumeration
2195 type, VQ is either volatile or empty, and R is a promoted integral
2196 type, there exist candidate operator functions of the form
2198 VQ L& operator%=(VQ L&, R);
2199 VQ L& operator<<=(VQ L&, R);
2200 VQ L& operator>>=(VQ L&, R);
2201 VQ L& operator&=(VQ L&, R);
2202 VQ L& operator^=(VQ L&, R);
2203 VQ L& operator|=(VQ L&, R); */
2210 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2212 type2 = ptrdiff_type_node;
2216 case TRUNC_DIV_EXPR:
2217 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2221 case TRUNC_MOD_EXPR:
2227 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2232 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2234 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2235 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2236 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2237 || ((TYPE_PTRMEMFUNC_P (type1)
2238 || TREE_CODE (type1) == POINTER_TYPE)
2239 && null_ptr_cst_p (args[1])))
2249 type1 = build_reference_type (type1);
2255 For every pair of promoted arithmetic types L and R, there
2256 exist candidate operator functions of the form
2258 LR operator?(bool, L, R);
2260 where LR is the result of the usual arithmetic conversions
2261 between types L and R.
2263 For every type T, where T is a pointer or pointer-to-member
2264 type, there exist candidate operator functions of the form T
2265 operator?(bool, T, T); */
2267 if (promoted_arithmetic_type_p (type1)
2268 && promoted_arithmetic_type_p (type2))
2272 /* Otherwise, the types should be pointers. */
2273 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2274 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2277 /* We don't check that the two types are the same; the logic
2278 below will actually create two candidates; one in which both
2279 parameter types are TYPE1, and one in which both parameter
2287 /* If we're dealing with two pointer types or two enumeral types,
2288 we need candidates for both of them. */
2289 if (type2 && !same_type_p (type1, type2)
2290 && TREE_CODE (type1) == TREE_CODE (type2)
2291 && (TREE_CODE (type1) == REFERENCE_TYPE
2292 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2293 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2294 || TYPE_PTRMEMFUNC_P (type1)
2295 || MAYBE_CLASS_TYPE_P (type1)
2296 || TREE_CODE (type1) == ENUMERAL_TYPE))
2298 build_builtin_candidate
2299 (candidates, fnname, type1, type1, args, argtypes, flags);
2300 build_builtin_candidate
2301 (candidates, fnname, type2, type2, args, argtypes, flags);
2305 build_builtin_candidate
2306 (candidates, fnname, type1, type2, args, argtypes, flags);
2310 type_decays_to (tree type)
2312 if (TREE_CODE (type) == ARRAY_TYPE)
2313 return build_pointer_type (TREE_TYPE (type));
2314 if (TREE_CODE (type) == FUNCTION_TYPE)
2315 return build_pointer_type (type);
2316 if (!MAYBE_CLASS_TYPE_P (type))
2317 type = cv_unqualified (type);
2321 /* There are three conditions of builtin candidates:
2323 1) bool-taking candidates. These are the same regardless of the input.
2324 2) pointer-pair taking candidates. These are generated for each type
2325 one of the input types converts to.
2326 3) arithmetic candidates. According to the standard, we should generate
2327 all of these, but I'm trying not to...
2329 Here we generate a superset of the possible candidates for this particular
2330 case. That is a subset of the full set the standard defines, plus some
2331 other cases which the standard disallows. add_builtin_candidate will
2332 filter out the invalid set. */
2335 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2336 enum tree_code code2, tree fnname, tree *args,
2341 tree type, argtypes[3], t;
2342 /* TYPES[i] is the set of possible builtin-operator parameter types
2343 we will consider for the Ith argument. */
2344 VEC(tree,gc) *types[2];
2347 for (i = 0; i < 3; ++i)
2350 argtypes[i] = unlowered_expr_type (args[i]);
2352 argtypes[i] = NULL_TREE;
2357 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2358 and VQ is either volatile or empty, there exist candidate operator
2359 functions of the form
2360 VQ T& operator++(VQ T&); */
2362 case POSTINCREMENT_EXPR:
2363 case PREINCREMENT_EXPR:
2364 case POSTDECREMENT_EXPR:
2365 case PREDECREMENT_EXPR:
2370 /* 24There also exist candidate operator functions of the form
2371 bool operator!(bool);
2372 bool operator&&(bool, bool);
2373 bool operator||(bool, bool); */
2375 case TRUTH_NOT_EXPR:
2376 build_builtin_candidate
2377 (candidates, fnname, boolean_type_node,
2378 NULL_TREE, args, argtypes, flags);
2381 case TRUTH_ORIF_EXPR:
2382 case TRUTH_ANDIF_EXPR:
2383 build_builtin_candidate
2384 (candidates, fnname, boolean_type_node,
2385 boolean_type_node, args, argtypes, flags);
2407 types[0] = make_tree_vector ();
2408 types[1] = make_tree_vector ();
2410 for (i = 0; i < 2; ++i)
2414 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2418 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2421 convs = lookup_conversions (argtypes[i],
2422 /*lookup_template_convs_p=*/false);
2424 if (code == COND_EXPR)
2426 if (real_lvalue_p (args[i]))
2427 VEC_safe_push (tree, gc, types[i],
2428 build_reference_type (argtypes[i]));
2430 VEC_safe_push (tree, gc, types[i],
2431 TYPE_MAIN_VARIANT (argtypes[i]));
2437 for (; convs; convs = TREE_CHAIN (convs))
2439 type = TREE_TYPE (convs);
2442 && (TREE_CODE (type) != REFERENCE_TYPE
2443 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2446 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2447 VEC_safe_push (tree, gc, types[i], type);
2449 type = non_reference (type);
2450 if (i != 0 || ! ref1)
2452 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2453 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2454 VEC_safe_push (tree, gc, types[i], type);
2455 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2456 type = type_promotes_to (type);
2459 if (! vec_member (type, types[i]))
2460 VEC_safe_push (tree, gc, types[i], type);
2465 if (code == COND_EXPR && real_lvalue_p (args[i]))
2466 VEC_safe_push (tree, gc, types[i],
2467 build_reference_type (argtypes[i]));
2468 type = non_reference (argtypes[i]);
2469 if (i != 0 || ! ref1)
2471 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2472 if (enum_p && UNSCOPED_ENUM_P (type))
2473 VEC_safe_push (tree, gc, types[i], type);
2474 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2475 type = type_promotes_to (type);
2477 VEC_safe_push (tree, gc, types[i], type);
2481 /* Run through the possible parameter types of both arguments,
2482 creating candidates with those parameter types. */
2483 FOR_EACH_VEC_ELT_REVERSE (tree, types[0], ix, t)
2488 if (!VEC_empty (tree, types[1]))
2489 FOR_EACH_VEC_ELT_REVERSE (tree, types[1], jx, u)
2490 add_builtin_candidate
2491 (candidates, code, code2, fnname, t,
2492 u, args, argtypes, flags);
2494 add_builtin_candidate
2495 (candidates, code, code2, fnname, t,
2496 NULL_TREE, args, argtypes, flags);
2499 release_tree_vector (types[0]);
2500 release_tree_vector (types[1]);
2504 /* If TMPL can be successfully instantiated as indicated by
2505 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2507 TMPL is the template. EXPLICIT_TARGS are any explicit template
2508 arguments. ARGLIST is the arguments provided at the call-site.
2509 This does not change ARGLIST. The RETURN_TYPE is the desired type
2510 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2511 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2512 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2514 static struct z_candidate*
2515 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2516 tree ctype, tree explicit_targs, tree first_arg,
2517 const VEC(tree,gc) *arglist, tree return_type,
2518 tree access_path, tree conversion_path,
2519 int flags, tree obj, unification_kind_t strict)
2521 int ntparms = DECL_NTPARMS (tmpl);
2522 tree targs = make_tree_vec (ntparms);
2523 unsigned int len = VEC_length (tree, arglist);
2524 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2525 unsigned int skip_without_in_chrg = 0;
2526 tree first_arg_without_in_chrg = first_arg;
2527 tree *args_without_in_chrg;
2528 unsigned int nargs_without_in_chrg;
2529 unsigned int ia, ix;
2531 struct z_candidate *cand;
2535 /* We don't do deduction on the in-charge parameter, the VTT
2536 parameter or 'this'. */
2537 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2539 if (first_arg_without_in_chrg != NULL_TREE)
2540 first_arg_without_in_chrg = NULL_TREE;
2542 ++skip_without_in_chrg;
2545 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2546 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2547 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2549 if (first_arg_without_in_chrg != NULL_TREE)
2550 first_arg_without_in_chrg = NULL_TREE;
2552 ++skip_without_in_chrg;
2555 if (len < skip_without_in_chrg)
2558 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2559 + (len - skip_without_in_chrg));
2560 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2562 if (first_arg_without_in_chrg != NULL_TREE)
2564 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2567 for (ix = skip_without_in_chrg;
2568 VEC_iterate (tree, arglist, ix, arg);
2571 args_without_in_chrg[ia] = arg;
2574 gcc_assert (ia == nargs_without_in_chrg);
2576 i = fn_type_unification (tmpl, explicit_targs, targs,
2577 args_without_in_chrg,
2578 nargs_without_in_chrg,
2579 return_type, strict, flags);
2584 fn = instantiate_template (tmpl, targs, tf_none);
2585 if (fn == error_mark_node)
2590 A member function template is never instantiated to perform the
2591 copy of a class object to an object of its class type.
2593 It's a little unclear what this means; the standard explicitly
2594 does allow a template to be used to copy a class. For example,
2599 template <class T> A(const T&);
2602 void g () { A a (f ()); }
2604 the member template will be used to make the copy. The section
2605 quoted above appears in the paragraph that forbids constructors
2606 whose only parameter is (a possibly cv-qualified variant of) the
2607 class type, and a logical interpretation is that the intent was
2608 to forbid the instantiation of member templates which would then
2610 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2612 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2613 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2618 if (obj != NULL_TREE)
2619 /* Aha, this is a conversion function. */
2620 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2621 access_path, conversion_path);
2623 cand = add_function_candidate (candidates, fn, ctype,
2624 first_arg, arglist, access_path,
2625 conversion_path, flags);
2626 if (DECL_TI_TEMPLATE (fn) != tmpl)
2627 /* This situation can occur if a member template of a template
2628 class is specialized. Then, instantiate_template might return
2629 an instantiation of the specialization, in which case the
2630 DECL_TI_TEMPLATE field will point at the original
2631 specialization. For example:
2633 template <class T> struct S { template <class U> void f(U);
2634 template <> void f(int) {}; };
2638 Here, TMPL will be template <class U> S<double>::f(U).
2639 And, instantiate template will give us the specialization
2640 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2641 for this will point at template <class T> template <> S<T>::f(int),
2642 so that we can find the definition. For the purposes of
2643 overload resolution, however, we want the original TMPL. */
2644 cand->template_decl = build_template_info (tmpl, targs);
2646 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2647 cand->explicit_targs = explicit_targs;
2651 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
2652 access_path, conversion_path, 0);
2656 static struct z_candidate *
2657 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2658 tree explicit_targs, tree first_arg,
2659 const VEC(tree,gc) *arglist, tree return_type,
2660 tree access_path, tree conversion_path, int flags,
2661 unification_kind_t strict)
2664 add_template_candidate_real (candidates, tmpl, ctype,
2665 explicit_targs, first_arg, arglist,
2666 return_type, access_path, conversion_path,
2667 flags, NULL_TREE, strict);
2671 static struct z_candidate *
2672 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2673 tree obj, tree first_arg,
2674 const VEC(tree,gc) *arglist,
2675 tree return_type, tree access_path,
2676 tree conversion_path)
2679 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2680 first_arg, arglist, return_type, access_path,
2681 conversion_path, 0, obj, DEDUCE_CONV);
2684 /* The CANDS are the set of candidates that were considered for
2685 overload resolution. Return the set of viable candidates, or CANDS
2686 if none are viable. If any of the candidates were viable, set
2687 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
2688 considered viable only if it is strictly viable. */
2690 static struct z_candidate*
2691 splice_viable (struct z_candidate *cands,
2695 struct z_candidate *viable;
2696 struct z_candidate **last_viable;
2697 struct z_candidate **cand;
2700 last_viable = &viable;
2701 *any_viable_p = false;
2706 struct z_candidate *c = *cand;
2707 if (strict_p ? c->viable == 1 : c->viable)
2712 last_viable = &c->next;
2713 *any_viable_p = true;
2719 return viable ? viable : cands;
2723 any_strictly_viable (struct z_candidate *cands)
2725 for (; cands; cands = cands->next)
2726 if (cands->viable == 1)
2731 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2732 words, it is about to become the "this" pointer for a member
2733 function call. Take the address of the object. */
2736 build_this (tree obj)
2738 /* In a template, we are only concerned about the type of the
2739 expression, so we can take a shortcut. */
2740 if (processing_template_decl)
2741 return build_address (obj);
2743 return cp_build_addr_expr (obj, tf_warning_or_error);
2746 /* Returns true iff functions are equivalent. Equivalent functions are
2747 not '==' only if one is a function-local extern function or if
2748 both are extern "C". */
2751 equal_functions (tree fn1, tree fn2)
2753 if (TREE_CODE (fn1) != TREE_CODE (fn2))
2755 if (TREE_CODE (fn1) == TEMPLATE_DECL)
2757 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2758 || DECL_EXTERN_C_FUNCTION_P (fn1))
2759 return decls_match (fn1, fn2);
2763 /* Print information about one overload candidate CANDIDATE. MSGSTR
2764 is the text to print before the candidate itself.
2766 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2767 to have been run through gettext by the caller. This wart makes
2768 life simpler in print_z_candidates and for the translators. */
2771 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2773 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2775 if (candidate->num_convs == 3)
2776 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2777 candidate->convs[0]->type,
2778 candidate->convs[1]->type,
2779 candidate->convs[2]->type);
2780 else if (candidate->num_convs == 2)
2781 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2782 candidate->convs[0]->type,
2783 candidate->convs[1]->type);
2785 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2786 candidate->convs[0]->type);
2788 else if (TYPE_P (candidate->fn))
2789 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2790 else if (candidate->viable == -1)
2791 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2792 else if (DECL_DELETED_FN (STRIP_TEMPLATE (candidate->fn)))
2793 inform (input_location, "%s %+#D <deleted>", msgstr, candidate->fn);
2795 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2799 print_z_candidates (struct z_candidate *candidates)
2802 struct z_candidate *cand1;
2803 struct z_candidate **cand2;
2809 /* Remove non-viable deleted candidates. */
2811 for (cand2 = &cand1; *cand2; )
2813 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2814 && !(*cand2)->viable
2815 && DECL_DELETED_FN ((*cand2)->fn))
2816 *cand2 = (*cand2)->next;
2818 cand2 = &(*cand2)->next;
2820 /* ...if there are any non-deleted ones. */
2824 /* There may be duplicates in the set of candidates. We put off
2825 checking this condition as long as possible, since we have no way
2826 to eliminate duplicates from a set of functions in less than n^2
2827 time. Now we are about to emit an error message, so it is more
2828 permissible to go slowly. */
2829 for (cand1 = candidates; cand1; cand1 = cand1->next)
2831 tree fn = cand1->fn;
2832 /* Skip builtin candidates and conversion functions. */
2835 cand2 = &cand1->next;
2838 if (DECL_P ((*cand2)->fn)
2839 && equal_functions (fn, (*cand2)->fn))
2840 *cand2 = (*cand2)->next;
2842 cand2 = &(*cand2)->next;
2846 str = candidates->next ? _("candidates are:") : _("candidate is:");
2848 for (; candidates; candidates = candidates->next)
2850 print_z_candidate (spaces ? spaces : str, candidates);
2851 spaces = spaces ? spaces : get_spaces (str);
2856 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2857 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2858 the result of the conversion function to convert it to the final
2859 desired type. Merge the two sequences into a single sequence,
2860 and return the merged sequence. */
2863 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2867 gcc_assert (user_seq->kind == ck_user);
2869 /* Find the end of the second conversion sequence. */
2871 while ((*t)->kind != ck_identity)
2872 t = &((*t)->u.next);
2874 /* Replace the identity conversion with the user conversion
2878 /* The entire sequence is a user-conversion sequence. */
2879 std_seq->user_conv_p = true;
2884 /* Handle overload resolution for initializing an object of class type from
2885 an initializer list. First we look for a suitable constructor that
2886 takes a std::initializer_list; if we don't find one, we then look for a
2887 non-list constructor.
2889 Parameters are as for add_candidates, except that the arguments are in
2890 the form of a CONSTRUCTOR (the initializer list) rather than a VEC, and
2891 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
2894 add_list_candidates (tree fns, tree first_arg,
2895 tree init_list, tree totype,
2896 tree explicit_targs, bool template_only,
2897 tree conversion_path, tree access_path,
2899 struct z_candidate **candidates)
2903 gcc_assert (*candidates == NULL);
2905 /* For list-initialization we consider explicit constructors, but
2906 give an error if one is selected. */
2907 flags &= ~LOOKUP_ONLYCONVERTING;
2908 /* And we don't allow narrowing conversions. We also use this flag to
2909 avoid the copy constructor call for copy-list-initialization. */
2910 flags |= LOOKUP_NO_NARROWING;
2912 /* Always use the default constructor if the list is empty (DR 990). */
2913 if (CONSTRUCTOR_NELTS (init_list) == 0
2914 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
2916 /* If the class has a list ctor, try passing the list as a single
2917 argument first, but only consider list ctors. */
2918 else if (TYPE_HAS_LIST_CTOR (totype))
2920 flags |= LOOKUP_LIST_ONLY;
2921 args = make_tree_vector_single (init_list);
2922 add_candidates (fns, first_arg, args, NULL_TREE,
2923 explicit_targs, template_only, conversion_path,
2924 access_path, flags, candidates);
2925 if (any_strictly_viable (*candidates))
2929 args = ctor_to_vec (init_list);
2931 /* We aren't looking for list-ctors anymore. */
2932 flags &= ~LOOKUP_LIST_ONLY;
2933 /* We allow more user-defined conversions within an init-list. */
2934 flags &= ~LOOKUP_NO_CONVERSION;
2935 /* But not for the copy ctor. */
2936 flags |= LOOKUP_NO_COPY_CTOR_CONVERSION;
2938 add_candidates (fns, first_arg, args, NULL_TREE,
2939 explicit_targs, template_only, conversion_path,
2940 access_path, flags, candidates);
2943 /* Returns the best overload candidate to perform the requested
2944 conversion. This function is used for three the overloading situations
2945 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2946 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2947 per [dcl.init.ref], so we ignore temporary bindings. */
2949 static struct z_candidate *
2950 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2952 struct z_candidate *candidates, *cand;
2953 tree fromtype = TREE_TYPE (expr);
2954 tree ctors = NULL_TREE;
2955 tree conv_fns = NULL_TREE;
2956 conversion *conv = NULL;
2957 tree first_arg = NULL_TREE;
2958 VEC(tree,gc) *args = NULL;
2962 /* We represent conversion within a hierarchy using RVALUE_CONV and
2963 BASE_CONV, as specified by [over.best.ics]; these become plain
2964 constructor calls, as specified in [dcl.init]. */
2965 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2966 || !DERIVED_FROM_P (totype, fromtype));
2968 if (MAYBE_CLASS_TYPE_P (totype))
2969 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2971 if (MAYBE_CLASS_TYPE_P (fromtype))
2973 tree to_nonref = non_reference (totype);
2974 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2975 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2976 && DERIVED_FROM_P (to_nonref, fromtype)))
2978 /* [class.conv.fct] A conversion function is never used to
2979 convert a (possibly cv-qualified) object to the (possibly
2980 cv-qualified) same object type (or a reference to it), to a
2981 (possibly cv-qualified) base class of that type (or a
2982 reference to it)... */
2985 conv_fns = lookup_conversions (fromtype,
2986 /*lookup_template_convs_p=*/true);
2990 flags |= LOOKUP_NO_CONVERSION;
2991 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
2992 flags |= LOOKUP_NO_NARROWING;
2994 /* It's OK to bind a temporary for converting constructor arguments, but
2995 not in converting the return value of a conversion operator. */
2996 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2997 flags &= ~LOOKUP_NO_TEMP_BIND;
3001 int ctorflags = flags;
3002 ctors = BASELINK_FUNCTIONS (ctors);
3004 first_arg = build_int_cst (build_pointer_type (totype), 0);
3006 /* We should never try to call the abstract or base constructor
3008 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3009 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3011 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3013 /* List-initialization. */
3014 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3015 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3016 ctorflags, &candidates);
3020 args = make_tree_vector_single (expr);
3021 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3022 TYPE_BINFO (totype), TYPE_BINFO (totype),
3023 ctorflags, &candidates);
3026 for (cand = candidates; cand; cand = cand->next)
3028 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3030 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3031 set, then this is copy-initialization. In that case, "The
3032 result of the call is then used to direct-initialize the
3033 object that is the destination of the copy-initialization."
3036 We represent this in the conversion sequence with an
3037 rvalue conversion, which means a constructor call. */
3038 if (TREE_CODE (totype) != REFERENCE_TYPE
3039 && !(convflags & LOOKUP_NO_TEMP_BIND))
3041 = build_conv (ck_rvalue, totype, cand->second_conv);
3046 first_arg = build_this (expr);
3048 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3050 tree conversion_path = TREE_PURPOSE (conv_fns);
3051 struct z_candidate *old_candidates;
3053 /* If we are called to convert to a reference type, we are trying to
3054 find an lvalue binding, so don't even consider temporaries. If
3055 we don't find an lvalue binding, the caller will try again to
3056 look for a temporary binding. */
3057 if (TREE_CODE (totype) == REFERENCE_TYPE)
3058 convflags |= LOOKUP_NO_TEMP_BIND;
3060 old_candidates = candidates;
3061 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3063 conversion_path, TYPE_BINFO (fromtype),
3064 flags, &candidates);
3066 for (cand = candidates; cand != old_candidates; cand = cand->next)
3069 = implicit_conversion (totype,
3070 TREE_TYPE (TREE_TYPE (cand->fn)),
3072 /*c_cast_p=*/false, convflags);
3074 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3075 copy-initialization. In that case, "The result of the
3076 call is then used to direct-initialize the object that is
3077 the destination of the copy-initialization." [dcl.init]
3079 We represent this in the conversion sequence with an
3080 rvalue conversion, which means a constructor call. But
3081 don't add a second rvalue conversion if there's already
3082 one there. Which there really shouldn't be, but it's
3083 harmless since we'd add it here anyway. */
3084 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3085 && !(convflags & LOOKUP_NO_TEMP_BIND))
3086 ics = build_conv (ck_rvalue, totype, ics);
3088 cand->second_conv = ics;
3092 else if (cand->viable == 1 && ics->bad_p)
3097 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3101 cand = tourney (candidates);
3104 if (flags & LOOKUP_COMPLAIN)
3106 error ("conversion from %qT to %qT is ambiguous",
3108 print_z_candidates (candidates);
3111 cand = candidates; /* any one will do */
3112 cand->second_conv = build_ambiguous_conv (totype, expr);
3113 cand->second_conv->user_conv_p = true;
3114 if (!any_strictly_viable (candidates))
3115 cand->second_conv->bad_p = true;
3116 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3117 ambiguous conversion is no worse than another user-defined
3123 /* Build the user conversion sequence. */
3126 (DECL_CONSTRUCTOR_P (cand->fn)
3127 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3128 build_identity_conv (TREE_TYPE (expr), expr));
3131 /* Remember that this was a list-initialization. */
3132 if (flags & LOOKUP_NO_NARROWING)
3133 conv->check_narrowing = true;
3135 /* Combine it with the second conversion sequence. */
3136 cand->second_conv = merge_conversion_sequences (conv,
3139 if (cand->viable == -1)
3140 cand->second_conv->bad_p = true;
3146 build_user_type_conversion (tree totype, tree expr, int flags)
3148 struct z_candidate *cand
3149 = build_user_type_conversion_1 (totype, expr, flags);
3153 if (cand->second_conv->kind == ck_ambig)
3154 return error_mark_node;
3155 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3156 return convert_from_reference (expr);
3161 /* Do any initial processing on the arguments to a function call. */
3163 static VEC(tree,gc) *
3164 resolve_args (VEC(tree,gc) *args)
3169 FOR_EACH_VEC_ELT (tree, args, ix, arg)
3171 if (error_operand_p (arg))
3173 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3175 error ("invalid use of void expression");
3178 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3184 /* Perform overload resolution on FN, which is called with the ARGS.
3186 Return the candidate function selected by overload resolution, or
3187 NULL if the event that overload resolution failed. In the case
3188 that overload resolution fails, *CANDIDATES will be the set of
3189 candidates considered, and ANY_VIABLE_P will be set to true or
3190 false to indicate whether or not any of the candidates were
3193 The ARGS should already have gone through RESOLVE_ARGS before this
3194 function is called. */
3196 static struct z_candidate *
3197 perform_overload_resolution (tree fn,
3198 const VEC(tree,gc) *args,
3199 struct z_candidate **candidates,
3202 struct z_candidate *cand;
3203 tree explicit_targs = NULL_TREE;
3204 int template_only = 0;
3207 *any_viable_p = true;
3210 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3211 || TREE_CODE (fn) == TEMPLATE_DECL
3212 || TREE_CODE (fn) == OVERLOAD
3213 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3215 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3217 explicit_targs = TREE_OPERAND (fn, 1);
3218 fn = TREE_OPERAND (fn, 0);
3222 /* Add the various candidate functions. */
3223 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3224 explicit_targs, template_only,
3225 /*conversion_path=*/NULL_TREE,
3226 /*access_path=*/NULL_TREE,
3230 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3234 cand = tourney (*candidates);
3238 /* Return an expression for a call to FN (a namespace-scope function,
3239 or a static member function) with the ARGS. This may change
3243 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3244 tsubst_flags_t complain)
3246 struct z_candidate *candidates, *cand;
3251 if (args != NULL && *args != NULL)
3253 *args = resolve_args (*args);
3255 return error_mark_node;
3258 /* If this function was found without using argument dependent
3259 lookup, then we want to ignore any undeclared friend
3265 fn = remove_hidden_names (fn);
3268 if (complain & tf_error)
3269 error ("no matching function for call to %<%D(%A)%>",
3270 DECL_NAME (OVL_CURRENT (orig_fn)),
3271 build_tree_list_vec (*args));
3272 return error_mark_node;
3276 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3277 p = conversion_obstack_alloc (0);
3279 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3283 if (complain & tf_error)
3285 if (!any_viable_p && candidates && ! candidates->next
3286 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
3287 return cp_build_function_call_vec (candidates->fn, args, complain);
3288 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3289 fn = TREE_OPERAND (fn, 0);
3291 error ("no matching function for call to %<%D(%A)%>",
3292 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3294 error ("call of overloaded %<%D(%A)%> is ambiguous",
3295 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3297 print_z_candidates (candidates);
3299 result = error_mark_node;
3302 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3304 /* Free all the conversions we allocated. */
3305 obstack_free (&conversion_obstack, p);
3310 /* Build a call to a global operator new. FNNAME is the name of the
3311 operator (either "operator new" or "operator new[]") and ARGS are
3312 the arguments provided. This may change ARGS. *SIZE points to the
3313 total number of bytes required by the allocation, and is updated if
3314 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3315 be used. If this function determines that no cookie should be
3316 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3317 non-NULL, it will be set, upon return, to the allocation function
3321 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3322 tree *size, tree *cookie_size,
3326 struct z_candidate *candidates;
3327 struct z_candidate *cand;
3332 VEC_safe_insert (tree, gc, *args, 0, *size);
3333 *args = resolve_args (*args);
3335 return error_mark_node;
3341 If this lookup fails to find the name, or if the allocated type
3342 is not a class type, the allocation function's name is looked
3343 up in the global scope.
3345 we disregard block-scope declarations of "operator new". */
3346 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3348 /* Figure out what function is being called. */
3349 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3351 /* If no suitable function could be found, issue an error message
3356 error ("no matching function for call to %<%D(%A)%>",
3357 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3359 error ("call of overloaded %<%D(%A)%> is ambiguous",
3360 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3362 print_z_candidates (candidates);
3363 return error_mark_node;
3366 /* If a cookie is required, add some extra space. Whether
3367 or not a cookie is required cannot be determined until
3368 after we know which function was called. */
3371 bool use_cookie = true;
3372 if (!abi_version_at_least (2))
3374 /* In G++ 3.2, the check was implemented incorrectly; it
3375 looked at the placement expression, rather than the
3376 type of the function. */
3377 if (VEC_length (tree, *args) == 2
3378 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3386 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3387 /* Skip the size_t parameter. */
3388 arg_types = TREE_CHAIN (arg_types);
3389 /* Check the remaining parameters (if any). */
3391 && TREE_CHAIN (arg_types) == void_list_node
3392 && same_type_p (TREE_VALUE (arg_types),
3396 /* If we need a cookie, adjust the number of bytes allocated. */
3399 /* Update the total size. */
3400 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3401 /* Update the argument list to reflect the adjusted size. */
3402 VEC_replace (tree, *args, 0, *size);
3405 *cookie_size = NULL_TREE;
3408 /* Tell our caller which function we decided to call. */
3412 /* Build the CALL_EXPR. */
3413 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3416 /* Build a new call to operator(). This may change ARGS. */
3419 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3421 struct z_candidate *candidates = 0, *cand;
3422 tree fns, convs, first_mem_arg = NULL_TREE;
3423 tree type = TREE_TYPE (obj);
3425 tree result = NULL_TREE;
3428 if (error_operand_p (obj))
3429 return error_mark_node;
3431 obj = prep_operand (obj);
3433 if (TYPE_PTRMEMFUNC_P (type))
3435 if (complain & tf_error)
3436 /* It's no good looking for an overloaded operator() on a
3437 pointer-to-member-function. */
3438 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3439 return error_mark_node;
3442 if (TYPE_BINFO (type))
3444 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3445 if (fns == error_mark_node)
3446 return error_mark_node;
3451 if (args != NULL && *args != NULL)
3453 *args = resolve_args (*args);
3455 return error_mark_node;
3458 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3459 p = conversion_obstack_alloc (0);
3463 first_mem_arg = build_this (obj);
3465 add_candidates (BASELINK_FUNCTIONS (fns),
3466 first_mem_arg, *args, NULL_TREE,
3468 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
3469 LOOKUP_NORMAL, &candidates);
3472 convs = lookup_conversions (type, /*lookup_template_convs_p=*/true);
3474 for (; convs; convs = TREE_CHAIN (convs))
3476 tree fns = TREE_VALUE (convs);
3477 tree totype = TREE_TYPE (convs);
3479 if ((TREE_CODE (totype) == POINTER_TYPE
3480 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3481 || (TREE_CODE (totype) == REFERENCE_TYPE
3482 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3483 || (TREE_CODE (totype) == REFERENCE_TYPE
3484 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3485 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3486 for (; fns; fns = OVL_NEXT (fns))
3488 tree fn = OVL_CURRENT (fns);
3490 if (DECL_NONCONVERTING_P (fn))
3493 if (TREE_CODE (fn) == TEMPLATE_DECL)
3494 add_template_conv_candidate
3495 (&candidates, fn, obj, NULL_TREE, *args, totype,
3496 /*access_path=*/NULL_TREE,
3497 /*conversion_path=*/NULL_TREE);
3499 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3500 *args, /*conversion_path=*/NULL_TREE,
3501 /*access_path=*/NULL_TREE);
3505 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3508 if (complain & tf_error)
3510 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3511 build_tree_list_vec (*args));
3512 print_z_candidates (candidates);
3514 result = error_mark_node;
3518 cand = tourney (candidates);
3521 if (complain & tf_error)
3523 error ("call of %<(%T) (%A)%> is ambiguous",
3524 TREE_TYPE (obj), build_tree_list_vec (*args));
3525 print_z_candidates (candidates);
3527 result = error_mark_node;
3529 /* Since cand->fn will be a type, not a function, for a conversion
3530 function, we must be careful not to unconditionally look at
3532 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3533 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3534 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3537 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3539 obj = convert_from_reference (obj);
3540 result = cp_build_function_call_vec (obj, args, complain);
3544 /* Free all the conversions we allocated. */
3545 obstack_free (&conversion_obstack, p);
3551 op_error (enum tree_code code, enum tree_code code2,
3552 tree arg1, tree arg2, tree arg3, bool match)
3556 if (code == MODIFY_EXPR)
3557 opname = assignment_operator_name_info[code2].name;
3559 opname = operator_name_info[code].name;
3565 error ("ambiguous overload for ternary %<operator?:%> "
3566 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3568 error ("no match for ternary %<operator?:%> "
3569 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
3572 case POSTINCREMENT_EXPR:
3573 case POSTDECREMENT_EXPR:
3575 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
3576 opname, arg1, opname);
3578 error ("no match for %<operator%s%> in %<%E%s%>",
3579 opname, arg1, opname);
3584 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
3587 error ("no match for %<operator[]%> in %<%E[%E]%>",
3594 error ("ambiguous overload for %qs in %<%s %E%>",
3595 opname, opname, arg1);
3597 error ("no match for %qs in %<%s %E%>",
3598 opname, opname, arg1);
3604 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
3605 opname, arg1, opname, arg2);
3607 error ("no match for %<operator%s%> in %<%E %s %E%>",
3608 opname, arg1, opname, arg2);
3611 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
3612 opname, opname, arg1);
3614 error ("no match for %<operator%s%> in %<%s%E%>",
3615 opname, opname, arg1);
3620 /* Return the implicit conversion sequence that could be used to
3621 convert E1 to E2 in [expr.cond]. */
3624 conditional_conversion (tree e1, tree e2)
3626 tree t1 = non_reference (TREE_TYPE (e1));
3627 tree t2 = non_reference (TREE_TYPE (e2));
3633 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3634 implicitly converted (clause _conv_) to the type "reference to
3635 T2", subject to the constraint that in the conversion the
3636 reference must bind directly (_dcl.init.ref_) to E1. */
3637 if (real_lvalue_p (e2))
3639 conv = implicit_conversion (build_reference_type (t2),
3643 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3650 If E1 and E2 have class type, and the underlying class types are
3651 the same or one is a base class of the other: E1 can be converted
3652 to match E2 if the class of T2 is the same type as, or a base
3653 class of, the class of T1, and the cv-qualification of T2 is the
3654 same cv-qualification as, or a greater cv-qualification than, the
3655 cv-qualification of T1. If the conversion is applied, E1 is
3656 changed to an rvalue of type T2 that still refers to the original
3657 source class object (or the appropriate subobject thereof). */
3658 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3659 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3661 if (good_base && at_least_as_qualified_p (t2, t1))
3663 conv = build_identity_conv (t1, e1);
3664 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3665 TYPE_MAIN_VARIANT (t2)))
3666 conv = build_conv (ck_base, t2, conv);
3668 conv = build_conv (ck_rvalue, t2, conv);
3677 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3678 converted to the type that expression E2 would have if E2 were
3679 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3680 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3684 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3685 arguments to the conditional expression. */
3688 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3689 tsubst_flags_t complain)
3693 tree result = NULL_TREE;
3694 tree result_type = NULL_TREE;
3695 bool lvalue_p = true;
3696 struct z_candidate *candidates = 0;
3697 struct z_candidate *cand;
3700 /* As a G++ extension, the second argument to the conditional can be
3701 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3702 c'.) If the second operand is omitted, make sure it is
3703 calculated only once. */
3706 if (complain & tf_error)
3707 pedwarn (input_location, OPT_pedantic,
3708 "ISO C++ forbids omitting the middle term of a ?: expression");
3710 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3711 if (real_lvalue_p (arg1))
3712 arg2 = arg1 = stabilize_reference (arg1);
3714 arg2 = arg1 = save_expr (arg1);
3719 The first expression is implicitly converted to bool (clause
3721 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
3724 /* If something has already gone wrong, just pass that fact up the
3726 if (error_operand_p (arg1)
3727 || error_operand_p (arg2)
3728 || error_operand_p (arg3))
3729 return error_mark_node;
3733 If either the second or the third operand has type (possibly
3734 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3735 array-to-pointer (_conv.array_), and function-to-pointer
3736 (_conv.func_) standard conversions are performed on the second
3737 and third operands. */
3738 arg2_type = unlowered_expr_type (arg2);
3739 arg3_type = unlowered_expr_type (arg3);
3740 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3742 /* Do the conversions. We don't these for `void' type arguments
3743 since it can't have any effect and since decay_conversion
3744 does not handle that case gracefully. */
3745 if (!VOID_TYPE_P (arg2_type))
3746 arg2 = decay_conversion (arg2);
3747 if (!VOID_TYPE_P (arg3_type))
3748 arg3 = decay_conversion (arg3);
3749 arg2_type = TREE_TYPE (arg2);
3750 arg3_type = TREE_TYPE (arg3);
3754 One of the following shall hold:
3756 --The second or the third operand (but not both) is a
3757 throw-expression (_except.throw_); the result is of the
3758 type of the other and is an rvalue.
3760 --Both the second and the third operands have type void; the
3761 result is of type void and is an rvalue.
3763 We must avoid calling force_rvalue for expressions of type
3764 "void" because it will complain that their value is being
3766 if (TREE_CODE (arg2) == THROW_EXPR
3767 && TREE_CODE (arg3) != THROW_EXPR)
3769 if (!VOID_TYPE_P (arg3_type))
3770 arg3 = force_rvalue (arg3);
3771 arg3_type = TREE_TYPE (arg3);
3772 result_type = arg3_type;
3774 else if (TREE_CODE (arg2) != THROW_EXPR
3775 && TREE_CODE (arg3) == THROW_EXPR)
3777 if (!VOID_TYPE_P (arg2_type))
3778 arg2 = force_rvalue (arg2);
3779 arg2_type = TREE_TYPE (arg2);
3780 result_type = arg2_type;
3782 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3783 result_type = void_type_node;
3786 if (complain & tf_error)
3788 if (VOID_TYPE_P (arg2_type))
3789 error ("second operand to the conditional operator "
3790 "is of type %<void%>, "
3791 "but the third operand is neither a throw-expression "
3792 "nor of type %<void%>");
3794 error ("third operand to the conditional operator "
3795 "is of type %<void%>, "
3796 "but the second operand is neither a throw-expression "
3797 "nor of type %<void%>");
3799 return error_mark_node;
3803 goto valid_operands;
3807 Otherwise, if the second and third operand have different types,
3808 and either has (possibly cv-qualified) class type, an attempt is
3809 made to convert each of those operands to the type of the other. */
3810 else if (!same_type_p (arg2_type, arg3_type)
3811 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3816 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3817 p = conversion_obstack_alloc (0);
3819 conv2 = conditional_conversion (arg2, arg3);
3820 conv3 = conditional_conversion (arg3, arg2);
3824 If both can be converted, or one can be converted but the
3825 conversion is ambiguous, the program is ill-formed. If
3826 neither can be converted, the operands are left unchanged and
3827 further checking is performed as described below. If exactly
3828 one conversion is possible, that conversion is applied to the
3829 chosen operand and the converted operand is used in place of
3830 the original operand for the remainder of this section. */
3831 if ((conv2 && !conv2->bad_p
3832 && conv3 && !conv3->bad_p)
3833 || (conv2 && conv2->kind == ck_ambig)
3834 || (conv3 && conv3->kind == ck_ambig))
3836 error ("operands to ?: have different types %qT and %qT",
3837 arg2_type, arg3_type);
3838 result = error_mark_node;
3840 else if (conv2 && (!conv2->bad_p || !conv3))
3842 arg2 = convert_like (conv2, arg2, complain);
3843 arg2 = convert_from_reference (arg2);
3844 arg2_type = TREE_TYPE (arg2);
3845 /* Even if CONV2 is a valid conversion, the result of the
3846 conversion may be invalid. For example, if ARG3 has type
3847 "volatile X", and X does not have a copy constructor
3848 accepting a "volatile X&", then even if ARG2 can be
3849 converted to X, the conversion will fail. */
3850 if (error_operand_p (arg2))
3851 result = error_mark_node;
3853 else if (conv3 && (!conv3->bad_p || !conv2))
3855 arg3 = convert_like (conv3, arg3, complain);
3856 arg3 = convert_from_reference (arg3);
3857 arg3_type = TREE_TYPE (arg3);
3858 if (error_operand_p (arg3))
3859 result = error_mark_node;
3862 /* Free all the conversions we allocated. */
3863 obstack_free (&conversion_obstack, p);
3868 /* If, after the conversion, both operands have class type,
3869 treat the cv-qualification of both operands as if it were the
3870 union of the cv-qualification of the operands.
3872 The standard is not clear about what to do in this
3873 circumstance. For example, if the first operand has type
3874 "const X" and the second operand has a user-defined
3875 conversion to "volatile X", what is the type of the second
3876 operand after this step? Making it be "const X" (matching
3877 the first operand) seems wrong, as that discards the
3878 qualification without actually performing a copy. Leaving it
3879 as "volatile X" seems wrong as that will result in the
3880 conditional expression failing altogether, even though,
3881 according to this step, the one operand could be converted to
3882 the type of the other. */
3883 if ((conv2 || conv3)
3884 && CLASS_TYPE_P (arg2_type)
3885 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
3886 arg2_type = arg3_type =
3887 cp_build_qualified_type (arg2_type,
3888 cp_type_quals (arg2_type)
3889 | cp_type_quals (arg3_type));
3894 If the second and third operands are lvalues and have the same
3895 type, the result is of that type and is an lvalue. */
3896 if (real_lvalue_p (arg2)
3897 && real_lvalue_p (arg3)
3898 && same_type_p (arg2_type, arg3_type))
3900 result_type = arg2_type;
3901 arg2 = mark_lvalue_use (arg2);
3902 arg3 = mark_lvalue_use (arg3);
3903 goto valid_operands;
3908 Otherwise, the result is an rvalue. If the second and third
3909 operand do not have the same type, and either has (possibly
3910 cv-qualified) class type, overload resolution is used to
3911 determine the conversions (if any) to be applied to the operands
3912 (_over.match.oper_, _over.built_). */
3914 if (!same_type_p (arg2_type, arg3_type)
3915 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3921 /* Rearrange the arguments so that add_builtin_candidate only has
3922 to know about two args. In build_builtin_candidate, the
3923 arguments are unscrambled. */
3927 add_builtin_candidates (&candidates,
3930 ansi_opname (COND_EXPR),
3936 If the overload resolution fails, the program is
3938 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3941 if (complain & tf_error)
3943 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3944 print_z_candidates (candidates);
3946 return error_mark_node;
3948 cand = tourney (candidates);
3951 if (complain & tf_error)
3953 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
3954 print_z_candidates (candidates);
3956 return error_mark_node;
3961 Otherwise, the conversions thus determined are applied, and
3962 the converted operands are used in place of the original
3963 operands for the remainder of this section. */
3964 conv = cand->convs[0];
3965 arg1 = convert_like (conv, arg1, complain);
3966 conv = cand->convs[1];
3967 arg2 = convert_like (conv, arg2, complain);
3968 arg2_type = TREE_TYPE (arg2);
3969 conv = cand->convs[2];
3970 arg3 = convert_like (conv, arg3, complain);
3971 arg3_type = TREE_TYPE (arg3);
3976 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3977 and function-to-pointer (_conv.func_) standard conversions are
3978 performed on the second and third operands.
3980 We need to force the lvalue-to-rvalue conversion here for class types,
3981 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3982 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3985 arg2 = force_rvalue (arg2);
3986 if (!CLASS_TYPE_P (arg2_type))
3987 arg2_type = TREE_TYPE (arg2);
3989 arg3 = force_rvalue (arg3);
3990 if (!CLASS_TYPE_P (arg3_type))
3991 arg3_type = TREE_TYPE (arg3);
3993 if (arg2 == error_mark_node || arg3 == error_mark_node)
3994 return error_mark_node;
3998 After those conversions, one of the following shall hold:
4000 --The second and third operands have the same type; the result is of
4002 if (same_type_p (arg2_type, arg3_type))
4003 result_type = arg2_type;
4006 --The second and third operands have arithmetic or enumeration
4007 type; the usual arithmetic conversions are performed to bring
4008 them to a common type, and the result is of that type. */
4009 else if ((ARITHMETIC_TYPE_P (arg2_type)
4010 || UNSCOPED_ENUM_P (arg2_type))
4011 && (ARITHMETIC_TYPE_P (arg3_type)
4012 || UNSCOPED_ENUM_P (arg3_type)))
4014 /* In this case, there is always a common type. */
4015 result_type = type_after_usual_arithmetic_conversions (arg2_type,
4017 do_warn_double_promotion (result_type, arg2_type, arg3_type,
4018 "implicit conversion from %qT to %qT to "
4019 "match other result of conditional",
4022 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
4023 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
4025 if (complain & tf_warning)
4027 "enumeral mismatch in conditional expression: %qT vs %qT",
4028 arg2_type, arg3_type);
4030 else if (extra_warnings
4031 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
4032 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
4033 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
4034 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
4036 if (complain & tf_warning)
4038 "enumeral and non-enumeral type in conditional expression");
4041 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4042 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4046 --The second and third operands have pointer type, or one has
4047 pointer type and the other is a null pointer constant; pointer
4048 conversions (_conv.ptr_) and qualification conversions
4049 (_conv.qual_) are performed to bring them to their composite
4050 pointer type (_expr.rel_). The result is of the composite
4053 --The second and third operands have pointer to member type, or
4054 one has pointer to member type and the other is a null pointer
4055 constant; pointer to member conversions (_conv.mem_) and
4056 qualification conversions (_conv.qual_) are performed to bring
4057 them to a common type, whose cv-qualification shall match the
4058 cv-qualification of either the second or the third operand.
4059 The result is of the common type. */
4060 else if ((null_ptr_cst_p (arg2)
4061 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
4062 || (null_ptr_cst_p (arg3)
4063 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
4064 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
4065 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
4066 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
4068 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
4069 arg3, CPO_CONDITIONAL_EXPR,
4071 if (result_type == error_mark_node)
4072 return error_mark_node;
4073 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4074 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4079 if (complain & tf_error)
4080 error ("operands to ?: have different types %qT and %qT",
4081 arg2_type, arg3_type);
4082 return error_mark_node;
4086 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4087 if (!cp_unevaluated_operand)
4088 /* Avoid folding within decltype (c++/42013) and noexcept. */
4089 result = fold_if_not_in_template (result);
4091 /* We can't use result_type below, as fold might have returned a
4096 /* Expand both sides into the same slot, hopefully the target of
4097 the ?: expression. We used to check for TARGET_EXPRs here,
4098 but now we sometimes wrap them in NOP_EXPRs so the test would
4100 if (CLASS_TYPE_P (TREE_TYPE (result)))
4101 result = get_target_expr (result);
4102 /* If this expression is an rvalue, but might be mistaken for an
4103 lvalue, we must add a NON_LVALUE_EXPR. */
4104 result = rvalue (result);
4110 /* OPERAND is an operand to an expression. Perform necessary steps
4111 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4115 prep_operand (tree operand)
4119 if (CLASS_TYPE_P (TREE_TYPE (operand))
4120 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4121 /* Make sure the template type is instantiated now. */
4122 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4128 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4129 OVERLOAD) to the CANDIDATES, returning an updated list of
4130 CANDIDATES. The ARGS are the arguments provided to the call;
4131 if FIRST_ARG is non-null it is the implicit object argument,
4132 otherwise the first element of ARGS is used if needed. The
4133 EXPLICIT_TARGS are explicit template arguments provided.
4134 TEMPLATE_ONLY is true if only template functions should be
4135 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4136 add_function_candidate. */
4139 add_candidates (tree fns, tree first_arg, const VEC(tree,gc) *args,
4141 tree explicit_targs, bool template_only,
4142 tree conversion_path, tree access_path,
4144 struct z_candidate **candidates)
4147 const VEC(tree,gc) *non_static_args;
4148 bool check_list_ctor;
4149 bool check_converting;
4150 unification_kind_t strict;
4156 /* Precalculate special handling of constructors and conversion ops. */
4157 fn = OVL_CURRENT (fns);
4158 if (DECL_CONV_FN_P (fn))
4160 check_list_ctor = false;
4161 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4162 if (flags & LOOKUP_NO_CONVERSION)
4163 /* We're doing return_type(x). */
4164 strict = DEDUCE_CONV;
4166 /* We're doing x.operator return_type(). */
4167 strict = DEDUCE_EXACT;
4168 /* [over.match.funcs] For conversion functions, the function
4169 is considered to be a member of the class of the implicit
4170 object argument for the purpose of defining the type of
4171 the implicit object parameter. */
4172 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (first_arg)));
4176 if (DECL_CONSTRUCTOR_P (fn))
4178 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
4179 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4183 check_list_ctor = false;
4184 check_converting = false;
4186 strict = DEDUCE_CALL;
4187 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4191 non_static_args = args;
4193 /* Delay creating the implicit this parameter until it is needed. */
4194 non_static_args = NULL;
4196 for (; fns; fns = OVL_NEXT (fns))
4199 const VEC(tree,gc) *fn_args;
4201 fn = OVL_CURRENT (fns);
4203 if (check_converting && DECL_NONCONVERTING_P (fn))
4205 if (check_list_ctor && !is_list_ctor (fn))
4208 /* Figure out which set of arguments to use. */
4209 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4211 /* If this function is a non-static member and we didn't get an
4212 implicit object argument, move it out of args. */
4213 if (first_arg == NULL_TREE)
4217 VEC(tree,gc) *tempvec
4218 = VEC_alloc (tree, gc, VEC_length (tree, args) - 1);
4219 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4220 VEC_quick_push (tree, tempvec, arg);
4221 non_static_args = tempvec;
4222 first_arg = build_this (VEC_index (tree, args, 0));
4225 fn_first_arg = first_arg;
4226 fn_args = non_static_args;
4230 /* Otherwise, just use the list of arguments provided. */
4231 fn_first_arg = NULL_TREE;
4235 if (TREE_CODE (fn) == TEMPLATE_DECL)
4236 add_template_candidate (candidates,
4247 else if (!template_only)
4248 add_function_candidate (candidates,
4259 /* Even unsigned enum types promote to signed int. We don't want to
4260 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4261 original argument and ARG is the argument after any conversions
4262 have been applied. We set TREE_NO_WARNING if we have added a cast
4263 from an unsigned enum type to a signed integer type. */
4266 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4268 if (orig_arg != NULL_TREE
4271 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4272 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4273 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4274 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4275 TREE_NO_WARNING (arg) = 1;
4279 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4280 bool *overloaded_p, tsubst_flags_t complain)
4282 tree orig_arg1 = arg1;
4283 tree orig_arg2 = arg2;
4284 tree orig_arg3 = arg3;
4285 struct z_candidate *candidates = 0, *cand;
4286 VEC(tree,gc) *arglist;
4289 tree result = NULL_TREE;
4290 bool result_valid_p = false;
4291 enum tree_code code2 = NOP_EXPR;
4292 enum tree_code code_orig_arg1 = ERROR_MARK;
4293 enum tree_code code_orig_arg2 = ERROR_MARK;
4299 if (error_operand_p (arg1)
4300 || error_operand_p (arg2)
4301 || error_operand_p (arg3))
4302 return error_mark_node;
4304 if (code == MODIFY_EXPR)
4306 code2 = TREE_CODE (arg3);
4308 fnname = ansi_assopname (code2);
4311 fnname = ansi_opname (code);
4313 arg1 = prep_operand (arg1);
4319 case VEC_DELETE_EXPR:
4321 /* Use build_op_new_call and build_op_delete_call instead. */
4325 /* Use build_op_call instead. */
4328 case TRUTH_ORIF_EXPR:
4329 case TRUTH_ANDIF_EXPR:
4330 case TRUTH_AND_EXPR:
4332 /* These are saved for the sake of warn_logical_operator. */
4333 code_orig_arg1 = TREE_CODE (arg1);
4334 code_orig_arg2 = TREE_CODE (arg2);
4340 arg2 = prep_operand (arg2);
4341 arg3 = prep_operand (arg3);
4343 if (code == COND_EXPR)
4344 /* Use build_conditional_expr instead. */
4346 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4347 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4350 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4351 arg2 = integer_zero_node;
4353 arglist = VEC_alloc (tree, gc, 3);
4354 VEC_quick_push (tree, arglist, arg1);
4355 if (arg2 != NULL_TREE)
4356 VEC_quick_push (tree, arglist, arg2);
4357 if (arg3 != NULL_TREE)
4358 VEC_quick_push (tree, arglist, arg3);
4360 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4361 p = conversion_obstack_alloc (0);
4363 /* Add namespace-scope operators to the list of functions to
4365 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4366 NULL_TREE, arglist, NULL_TREE,
4367 NULL_TREE, false, NULL_TREE, NULL_TREE,
4368 flags, &candidates);
4369 /* Add class-member operators to the candidate set. */
4370 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4374 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4375 if (fns == error_mark_node)
4377 result = error_mark_node;
4378 goto user_defined_result_ready;
4381 add_candidates (BASELINK_FUNCTIONS (fns),
4382 NULL_TREE, arglist, NULL_TREE,
4384 BASELINK_BINFO (fns),
4385 BASELINK_ACCESS_BINFO (fns),
4386 flags, &candidates);
4391 args[2] = NULL_TREE;
4393 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4399 /* For these, the built-in candidates set is empty
4400 [over.match.oper]/3. We don't want non-strict matches
4401 because exact matches are always possible with built-in
4402 operators. The built-in candidate set for COMPONENT_REF
4403 would be empty too, but since there are no such built-in
4404 operators, we accept non-strict matches for them. */
4409 strict_p = pedantic;
4413 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4418 case POSTINCREMENT_EXPR:
4419 case POSTDECREMENT_EXPR:
4420 /* Don't try anything fancy if we're not allowed to produce
4422 if (!(complain & tf_error))
4423 return error_mark_node;
4425 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4426 distinguish between prefix and postfix ++ and
4427 operator++() was used for both, so we allow this with
4429 if (flags & LOOKUP_COMPLAIN)
4431 const char *msg = (flag_permissive)
4432 ? G_("no %<%D(int)%> declared for postfix %qs,"
4433 " trying prefix operator instead")
4434 : G_("no %<%D(int)%> declared for postfix %qs");
4435 permerror (input_location, msg, fnname,
4436 operator_name_info[code].name);
4439 if (!flag_permissive)
4440 return error_mark_node;
4442 if (code == POSTINCREMENT_EXPR)
4443 code = PREINCREMENT_EXPR;
4445 code = PREDECREMENT_EXPR;
4446 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4447 overloaded_p, complain);
4450 /* The caller will deal with these. */
4455 result_valid_p = true;
4459 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4461 /* If one of the arguments of the operator represents
4462 an invalid use of member function pointer, try to report
4463 a meaningful error ... */
4464 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4465 || invalid_nonstatic_memfn_p (arg2, tf_error)
4466 || invalid_nonstatic_memfn_p (arg3, tf_error))
4467 /* We displayed the error message. */;
4470 /* ... Otherwise, report the more generic
4471 "no matching operator found" error */
4472 op_error (code, code2, arg1, arg2, arg3, FALSE);
4473 print_z_candidates (candidates);
4476 result = error_mark_node;
4482 cand = tourney (candidates);
4485 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4487 op_error (code, code2, arg1, arg2, arg3, TRUE);
4488 print_z_candidates (candidates);
4490 result = error_mark_node;
4492 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4495 *overloaded_p = true;
4497 if (resolve_args (arglist) == NULL)
4498 result = error_mark_node;
4500 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4504 /* Give any warnings we noticed during overload resolution. */
4505 if (cand->warnings && (complain & tf_warning))
4507 struct candidate_warning *w;
4508 for (w = cand->warnings; w; w = w->next)
4509 joust (cand, w->loser, 1);
4512 /* Check for comparison of different enum types. */
4521 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4522 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4523 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4524 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4525 && (complain & tf_warning))
4527 warning (OPT_Wenum_compare,
4528 "comparison between %q#T and %q#T",
4529 TREE_TYPE (arg1), TREE_TYPE (arg2));
4536 /* We need to strip any leading REF_BIND so that bitfields
4537 don't cause errors. This should not remove any important
4538 conversions, because builtins don't apply to class
4539 objects directly. */
4540 conv = cand->convs[0];
4541 if (conv->kind == ck_ref_bind)
4542 conv = conv->u.next;
4543 arg1 = convert_like (conv, arg1, complain);
4547 /* We need to call warn_logical_operator before
4548 converting arg2 to a boolean_type. */
4549 if (complain & tf_warning)
4550 warn_logical_operator (input_location, code, boolean_type_node,
4551 code_orig_arg1, arg1,
4552 code_orig_arg2, arg2);
4554 conv = cand->convs[1];
4555 if (conv->kind == ck_ref_bind)
4556 conv = conv->u.next;
4557 arg2 = convert_like (conv, arg2, complain);
4561 conv = cand->convs[2];
4562 if (conv->kind == ck_ref_bind)
4563 conv = conv->u.next;
4564 arg3 = convert_like (conv, arg3, complain);
4570 user_defined_result_ready:
4572 /* Free all the conversions we allocated. */
4573 obstack_free (&conversion_obstack, p);
4575 if (result || result_valid_p)
4579 avoid_sign_compare_warnings (orig_arg1, arg1);
4580 avoid_sign_compare_warnings (orig_arg2, arg2);
4581 avoid_sign_compare_warnings (orig_arg3, arg3);
4586 return cp_build_modify_expr (arg1, code2, arg2, complain);
4589 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
4591 case TRUTH_ANDIF_EXPR:
4592 case TRUTH_ORIF_EXPR:
4593 case TRUTH_AND_EXPR:
4595 warn_logical_operator (input_location, code, boolean_type_node,
4596 code_orig_arg1, arg1, code_orig_arg2, arg2);
4601 case TRUNC_DIV_EXPR:
4612 case TRUNC_MOD_EXPR:
4616 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4618 case UNARY_PLUS_EXPR:
4621 case TRUTH_NOT_EXPR:
4622 case PREINCREMENT_EXPR:
4623 case POSTINCREMENT_EXPR:
4624 case PREDECREMENT_EXPR:
4625 case POSTDECREMENT_EXPR:
4628 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4631 return cp_build_array_ref (input_location, arg1, arg2, complain);
4634 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
4638 /* The caller will deal with these. */
4650 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
4651 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
4654 non_placement_deallocation_fn_p (tree t)
4656 /* A template instance is never a usual deallocation function,
4657 regardless of its signature. */
4658 if (TREE_CODE (t) == TEMPLATE_DECL
4659 || primary_template_instantiation_p (t))
4662 /* If a class T has a member deallocation function named operator delete
4663 with exactly one parameter, then that function is a usual
4664 (non-placement) deallocation function. If class T does not declare
4665 such an operator delete but does declare a member deallocation
4666 function named operator delete with exactly two parameters, the second
4667 of which has type std::size_t (18.2), then this function is a usual
4668 deallocation function. */
4669 t = FUNCTION_ARG_CHAIN (t);
4670 if (t == void_list_node
4671 || (t && same_type_p (TREE_VALUE (t), size_type_node)
4672 && TREE_CHAIN (t) == void_list_node))
4677 /* Build a call to operator delete. This has to be handled very specially,
4678 because the restrictions on what signatures match are different from all
4679 other call instances. For a normal delete, only a delete taking (void *)
4680 or (void *, size_t) is accepted. For a placement delete, only an exact
4681 match with the placement new is accepted.
4683 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4684 ADDR is the pointer to be deleted.
4685 SIZE is the size of the memory block to be deleted.
4686 GLOBAL_P is true if the delete-expression should not consider
4687 class-specific delete operators.
4688 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4690 If this call to "operator delete" is being generated as part to
4691 deallocate memory allocated via a new-expression (as per [expr.new]
4692 which requires that if the initialization throws an exception then
4693 we call a deallocation function), then ALLOC_FN is the allocation
4697 build_op_delete_call (enum tree_code code, tree addr, tree size,
4698 bool global_p, tree placement,
4701 tree fn = NULL_TREE;
4702 tree fns, fnname, type, t;
4704 if (addr == error_mark_node)
4705 return error_mark_node;
4707 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4709 fnname = ansi_opname (code);
4711 if (CLASS_TYPE_P (type)
4712 && COMPLETE_TYPE_P (complete_type (type))
4716 If the result of the lookup is ambiguous or inaccessible, or if
4717 the lookup selects a placement deallocation function, the
4718 program is ill-formed.
4720 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4722 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4723 if (fns == error_mark_node)
4724 return error_mark_node;
4729 if (fns == NULL_TREE)
4730 fns = lookup_name_nonclass (fnname);
4732 /* Strip const and volatile from addr. */
4733 addr = cp_convert (ptr_type_node, addr);
4737 /* "A declaration of a placement deallocation function matches the
4738 declaration of a placement allocation function if it has the same
4739 number of parameters and, after parameter transformations (8.3.5),
4740 all parameter types except the first are identical."
4742 So we build up the function type we want and ask instantiate_type
4743 to get it for us. */
4744 t = FUNCTION_ARG_CHAIN (alloc_fn);
4745 t = tree_cons (NULL_TREE, ptr_type_node, t);
4746 t = build_function_type (void_type_node, t);
4748 fn = instantiate_type (t, fns, tf_none);
4749 if (fn == error_mark_node)
4752 if (BASELINK_P (fn))
4753 fn = BASELINK_FUNCTIONS (fn);
4755 /* "If the lookup finds the two-parameter form of a usual deallocation
4756 function (3.7.4.2) and that function, considered as a placement
4757 deallocation function, would have been selected as a match for the
4758 allocation function, the program is ill-formed." */
4759 if (non_placement_deallocation_fn_p (fn))
4761 /* But if the class has an operator delete (void *), then that is
4762 the usual deallocation function, so we shouldn't complain
4763 about using the operator delete (void *, size_t). */
4764 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4765 t; t = OVL_NEXT (t))
4767 tree elt = OVL_CURRENT (t);
4768 if (non_placement_deallocation_fn_p (elt)
4769 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
4772 permerror (0, "non-placement deallocation function %q+D", fn);
4773 permerror (input_location, "selected for placement delete");
4778 /* "Any non-placement deallocation function matches a non-placement
4779 allocation function. If the lookup finds a single matching
4780 deallocation function, that function will be called; otherwise, no
4781 deallocation function will be called." */
4782 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4783 t; t = OVL_NEXT (t))
4785 tree elt = OVL_CURRENT (t);
4786 if (non_placement_deallocation_fn_p (elt))
4789 /* "If a class T has a member deallocation function named
4790 operator delete with exactly one parameter, then that
4791 function is a usual (non-placement) deallocation
4792 function. If class T does not declare such an operator
4793 delete but does declare a member deallocation function named
4794 operator delete with exactly two parameters, the second of
4795 which has type std::size_t (18.2), then this function is a
4796 usual deallocation function."
4798 So (void*) beats (void*, size_t). */
4799 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4804 /* If we have a matching function, call it. */
4807 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
4809 /* If the FN is a member function, make sure that it is
4811 if (BASELINK_P (fns))
4812 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
4814 /* Core issue 901: It's ok to new a type with deleted delete. */
4815 if (DECL_DELETED_FN (fn) && alloc_fn)
4820 /* The placement args might not be suitable for overload
4821 resolution at this point, so build the call directly. */
4822 int nargs = call_expr_nargs (placement);
4823 tree *argarray = XALLOCAVEC (tree, nargs);
4826 for (i = 1; i < nargs; i++)
4827 argarray[i] = CALL_EXPR_ARG (placement, i);
4829 return build_cxx_call (fn, nargs, argarray);
4834 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4835 VEC_quick_push (tree, args, addr);
4836 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
4837 VEC_quick_push (tree, args, size);
4838 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4839 VEC_free (tree, gc, args);
4846 If no unambiguous matching deallocation function can be found,
4847 propagating the exception does not cause the object's memory to
4852 warning (0, "no corresponding deallocation function for %qD",
4857 error ("no suitable %<operator %s%> for %qT",
4858 operator_name_info[(int)code].name, type);
4859 return error_mark_node;
4862 /* If the current scope isn't allowed to access DECL along
4863 BASETYPE_PATH, give an error. The most derived class in
4864 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4865 the declaration to use in the error diagnostic. */
4868 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4870 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4872 if (!accessible_p (basetype_path, decl, true))
4874 if (TREE_PRIVATE (decl))
4875 error ("%q+#D is private", diag_decl);
4876 else if (TREE_PROTECTED (decl))
4877 error ("%q+#D is protected", diag_decl);
4879 error ("%q+#D is inaccessible", diag_decl);
4880 error ("within this context");
4887 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4888 bitwise or of LOOKUP_* values. If any errors are warnings are
4889 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4890 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4894 build_temp (tree expr, tree type, int flags,
4895 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
4900 savew = warningcount, savee = errorcount;
4901 args = make_tree_vector_single (expr);
4902 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4903 &args, type, flags, complain);
4904 release_tree_vector (args);
4905 if (warningcount > savew)
4906 *diagnostic_kind = DK_WARNING;
4907 else if (errorcount > savee)
4908 *diagnostic_kind = DK_ERROR;
4910 *diagnostic_kind = DK_UNSPECIFIED;
4914 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4915 EXPR is implicitly converted to type TOTYPE.
4916 FN and ARGNUM are used for diagnostics. */
4919 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4921 tree t = non_reference (totype);
4923 /* Issue warnings about peculiar, but valid, uses of NULL. */
4924 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4927 warning_at (input_location, OPT_Wconversion_null,
4928 "passing NULL to non-pointer argument %P of %qD",
4931 warning_at (input_location, OPT_Wconversion_null,
4932 "converting to non-pointer type %qT from NULL", t);
4935 /* Issue warnings if "false" is converted to a NULL pointer */
4936 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4937 warning_at (input_location, OPT_Wconversion_null,
4938 "converting %<false%> to pointer type for argument %P of %qD",
4942 /* Perform the conversions in CONVS on the expression EXPR. FN and
4943 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4944 indicates the `this' argument of a method. INNER is nonzero when
4945 being called to continue a conversion chain. It is negative when a
4946 reference binding will be applied, positive otherwise. If
4947 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4948 conversions will be emitted if appropriate. If C_CAST_P is true,
4949 this conversion is coming from a C-style cast; in that case,
4950 conversions to inaccessible bases are permitted. */
4953 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4954 int inner, bool issue_conversion_warnings,
4955 bool c_cast_p, tsubst_flags_t complain)
4957 tree totype = convs->type;
4958 diagnostic_t diag_kind;
4962 && convs->kind != ck_user
4963 && convs->kind != ck_list
4964 && convs->kind != ck_ambig
4965 && convs->kind != ck_ref_bind
4966 && convs->kind != ck_rvalue
4967 && convs->kind != ck_base)
4969 conversion *t = convs;
4971 /* Give a helpful error if this is bad because of excess braces. */
4972 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4973 && SCALAR_TYPE_P (totype)
4974 && CONSTRUCTOR_NELTS (expr) > 0
4975 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4976 permerror (input_location, "too many braces around initializer for %qT", totype);
4978 for (; t; t = convs->u.next)
4980 if (t->kind == ck_user || !t->bad_p)
4982 expr = convert_like_real (t, expr, fn, argnum, 1,
4983 /*issue_conversion_warnings=*/false,
4988 else if (t->kind == ck_ambig)
4989 return convert_like_real (t, expr, fn, argnum, 1,
4990 /*issue_conversion_warnings=*/false,
4993 else if (t->kind == ck_identity)
4996 if (complain & tf_error)
4998 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
5000 permerror (DECL_SOURCE_LOCATION (fn),
5001 " initializing argument %P of %qD", argnum, fn);
5004 return error_mark_node;
5006 return cp_convert (totype, expr);
5009 if (issue_conversion_warnings && (complain & tf_warning))
5010 conversion_null_warnings (totype, expr, fn, argnum);
5012 switch (convs->kind)
5016 struct z_candidate *cand = convs->cand;
5017 tree convfn = cand->fn;
5020 expr = mark_rvalue_use (expr);
5022 /* When converting from an init list we consider explicit
5023 constructors, but actually trying to call one is an error. */
5024 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
5025 /* Unless we're calling it for value-initialization from an
5026 empty list, since that is handled separately in 8.5.4. */
5027 && cand->num_convs > 0)
5029 if (complain & tf_error)
5030 error ("converting to %qT from initializer list would use "
5031 "explicit constructor %qD", totype, convfn);
5033 return error_mark_node;
5036 /* Set user_conv_p on the argument conversions, so rvalue/base
5037 handling knows not to allow any more UDCs. */
5038 for (i = 0; i < cand->num_convs; ++i)
5039 cand->convs[i]->user_conv_p = true;
5041 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
5043 /* If this is a constructor or a function returning an aggr type,
5044 we need to build up a TARGET_EXPR. */
5045 if (DECL_CONSTRUCTOR_P (convfn))
5047 expr = build_cplus_new (totype, expr);
5049 /* Remember that this was list-initialization. */
5050 if (convs->check_narrowing)
5051 TARGET_EXPR_LIST_INIT_P (expr) = true;
5057 expr = mark_rvalue_use (expr);
5058 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
5060 int nelts = CONSTRUCTOR_NELTS (expr);
5062 expr = build_value_init (totype, tf_warning_or_error);
5063 else if (nelts == 1)
5064 expr = CONSTRUCTOR_ELT (expr, 0)->value;
5069 if (type_unknown_p (expr))
5070 expr = instantiate_type (totype, expr, complain);
5071 /* Convert a constant to its underlying value, unless we are
5072 about to bind it to a reference, in which case we need to
5073 leave it as an lvalue. */
5076 expr = decl_constant_value (expr);
5077 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
5078 /* If __null has been converted to an integer type, we do not
5079 want to warn about uses of EXPR as an integer, rather than
5081 expr = build_int_cst (totype, 0);
5085 if (complain & tf_error)
5087 /* Call build_user_type_conversion again for the error. */
5088 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL);
5090 error (" initializing argument %P of %q+D", argnum, fn);
5092 return error_mark_node;
5096 /* Conversion to std::initializer_list<T>. */
5097 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
5098 tree new_ctor = build_constructor (init_list_type_node, NULL);
5099 unsigned len = CONSTRUCTOR_NELTS (expr);
5101 VEC(tree,gc) *parms;
5104 /* Convert all the elements. */
5105 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
5107 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
5108 1, false, false, complain);
5109 if (sub == error_mark_node)
5111 check_narrowing (TREE_TYPE (sub), val);
5112 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
5114 /* Build up the array. */
5115 elttype = cp_build_qualified_type
5116 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
5117 array = build_array_of_n_type (elttype, len);
5118 array = finish_compound_literal (array, new_ctor);
5120 parms = make_tree_vector ();
5121 VEC_safe_push (tree, gc, parms, decay_conversion (array));
5122 VEC_safe_push (tree, gc, parms, size_int (len));
5123 /* Call the private constructor. */
5124 push_deferring_access_checks (dk_no_check);
5125 new_ctor = build_special_member_call
5126 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
5127 release_tree_vector (parms);
5128 pop_deferring_access_checks ();
5129 return build_cplus_new (totype, new_ctor);
5133 return get_target_expr (digest_init (totype, expr));
5139 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5140 convs->kind == ck_ref_bind ? -1 : 1,
5141 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5144 if (expr == error_mark_node)
5145 return error_mark_node;
5147 switch (convs->kind)
5150 expr = decay_conversion (expr);
5151 if (! MAYBE_CLASS_TYPE_P (totype))
5153 /* Else fall through. */
5155 if (convs->kind == ck_base && !convs->need_temporary_p)
5157 /* We are going to bind a reference directly to a base-class
5158 subobject of EXPR. */
5159 /* Build an expression for `*((base*) &expr)'. */
5160 expr = cp_build_addr_expr (expr, complain);
5161 expr = convert_to_base (expr, build_pointer_type (totype),
5162 !c_cast_p, /*nonnull=*/true, complain);
5163 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5167 /* Copy-initialization where the cv-unqualified version of the source
5168 type is the same class as, or a derived class of, the class of the
5169 destination [is treated as direct-initialization]. [dcl.init] */
5170 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5171 if (convs->user_conv_p)
5172 /* This conversion is being done in the context of a user-defined
5173 conversion (i.e. the second step of copy-initialization), so
5174 don't allow any more. */
5175 flags |= LOOKUP_NO_CONVERSION;
5176 expr = build_temp (expr, totype, flags, &diag_kind, complain);
5177 if (diag_kind && fn)
5179 if ((complain & tf_error))
5180 emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), 0,
5181 " initializing argument %P of %qD", argnum, fn);
5182 else if (diag_kind == DK_ERROR)
5183 return error_mark_node;
5185 return build_cplus_new (totype, expr);
5189 tree ref_type = totype;
5191 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5192 && real_lvalue_p (expr))
5194 if (complain & tf_error)
5196 error ("cannot bind %qT lvalue to %qT",
5197 TREE_TYPE (expr), totype);
5199 error (" initializing argument %P of %q+D", argnum, fn);
5201 return error_mark_node;
5204 /* If necessary, create a temporary.
5206 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5207 that need temporaries, even when their types are reference
5208 compatible with the type of reference being bound, so the
5209 upcoming call to cp_build_addr_expr doesn't fail. */
5210 if (convs->need_temporary_p
5211 || TREE_CODE (expr) == CONSTRUCTOR
5212 || TREE_CODE (expr) == VA_ARG_EXPR)
5214 /* Otherwise, a temporary of type "cv1 T1" is created and
5215 initialized from the initializer expression using the rules
5216 for a non-reference copy-initialization (8.5). */
5218 tree type = TREE_TYPE (ref_type);
5219 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5221 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5222 (type, convs->u.next->type));
5223 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
5224 && !TYPE_REF_IS_RVALUE (ref_type))
5226 if (complain & tf_error)
5228 /* If the reference is volatile or non-const, we
5229 cannot create a temporary. */
5230 if (lvalue & clk_bitfield)
5231 error ("cannot bind bitfield %qE to %qT",
5233 else if (lvalue & clk_packed)
5234 error ("cannot bind packed field %qE to %qT",
5237 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5239 return error_mark_node;
5241 /* If the source is a packed field, and we must use a copy
5242 constructor, then building the target expr will require
5243 binding the field to the reference parameter to the
5244 copy constructor, and we'll end up with an infinite
5245 loop. If we can use a bitwise copy, then we'll be
5247 if ((lvalue & clk_packed)
5248 && CLASS_TYPE_P (type)
5249 && type_has_nontrivial_copy_init (type))
5251 if (complain & tf_error)
5252 error ("cannot bind packed field %qE to %qT",
5254 return error_mark_node;
5256 if (lvalue & clk_bitfield)
5258 expr = convert_bitfield_to_declared_type (expr);
5259 expr = fold_convert (type, expr);
5261 expr = build_target_expr_with_type (expr, type);
5264 /* Take the address of the thing to which we will bind the
5266 expr = cp_build_addr_expr (expr, complain);
5267 if (expr == error_mark_node)
5268 return error_mark_node;
5270 /* Convert it to a pointer to the type referred to by the
5271 reference. This will adjust the pointer if a derived to
5272 base conversion is being performed. */
5273 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5275 /* Convert the pointer to the desired reference type. */
5276 return build_nop (ref_type, expr);
5280 return decay_conversion (expr);
5283 /* Warn about deprecated conversion if appropriate. */
5284 string_conv_p (totype, expr, 1);
5289 expr = convert_to_base (expr, totype, !c_cast_p,
5290 /*nonnull=*/false, complain);
5291 return build_nop (totype, expr);
5294 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5295 c_cast_p, complain);
5301 if (convs->check_narrowing)
5302 check_narrowing (totype, expr);
5304 if (issue_conversion_warnings && (complain & tf_warning))
5305 expr = convert_and_check (totype, expr);
5307 expr = convert (totype, expr);
5312 /* ARG is being passed to a varargs function. Perform any conversions
5313 required. Return the converted value. */
5316 convert_arg_to_ellipsis (tree arg)
5322 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5323 standard conversions are performed. */
5324 arg = decay_conversion (arg);
5325 arg_type = TREE_TYPE (arg);
5328 If the argument has integral or enumeration type that is subject
5329 to the integral promotions (_conv.prom_), or a floating point
5330 type that is subject to the floating point promotion
5331 (_conv.fpprom_), the value of the argument is converted to the
5332 promoted type before the call. */
5333 if (TREE_CODE (arg_type) == REAL_TYPE
5334 && (TYPE_PRECISION (arg_type)
5335 < TYPE_PRECISION (double_type_node))
5336 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
5338 if (warn_double_promotion && !c_inhibit_evaluation_warnings)
5339 warning (OPT_Wdouble_promotion,
5340 "implicit conversion from %qT to %qT when passing "
5341 "argument to function",
5342 arg_type, double_type_node);
5343 arg = convert_to_real (double_type_node, arg);
5345 else if (NULLPTR_TYPE_P (arg_type))
5346 arg = null_pointer_node;
5347 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
5348 arg = perform_integral_promotions (arg);
5350 arg = require_complete_type (arg);
5351 arg_type = TREE_TYPE (arg);
5353 if (arg != error_mark_node
5354 && (type_has_nontrivial_copy_init (arg_type)
5355 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
5357 /* [expr.call] 5.2.2/7:
5358 Passing a potentially-evaluated argument of class type (Clause 9)
5359 with a non-trivial copy constructor or a non-trivial destructor
5360 with no corresponding parameter is conditionally-supported, with
5361 implementation-defined semantics.
5363 We used to just warn here and do a bitwise copy, but now
5364 cp_expr_size will abort if we try to do that.
5366 If the call appears in the context of a sizeof expression,
5367 it is not potentially-evaluated. */
5368 if (cp_unevaluated_operand == 0)
5369 error ("cannot pass objects of non-trivially-copyable "
5370 "type %q#T through %<...%>", arg_type);
5376 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5379 build_x_va_arg (tree expr, tree type)
5381 if (processing_template_decl)
5382 return build_min (VA_ARG_EXPR, type, expr);
5384 type = complete_type_or_else (type, NULL_TREE);
5386 if (expr == error_mark_node || !type)
5387 return error_mark_node;
5389 expr = mark_lvalue_use (expr);
5391 if (type_has_nontrivial_copy_init (type)
5392 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5393 || TREE_CODE (type) == REFERENCE_TYPE)
5395 /* Remove reference types so we don't ICE later on. */
5396 tree type1 = non_reference (type);
5397 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5398 error ("cannot receive objects of non-trivially-copyable type %q#T "
5399 "through %<...%>; ", type);
5400 expr = convert (build_pointer_type (type1), null_node);
5401 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
5405 return build_va_arg (input_location, expr, type);
5408 /* TYPE has been given to va_arg. Apply the default conversions which
5409 would have happened when passed via ellipsis. Return the promoted
5410 type, or the passed type if there is no change. */
5413 cxx_type_promotes_to (tree type)
5417 /* Perform the array-to-pointer and function-to-pointer
5419 type = type_decays_to (type);
5421 promote = type_promotes_to (type);
5422 if (same_type_p (type, promote))
5428 /* ARG is a default argument expression being passed to a parameter of
5429 the indicated TYPE, which is a parameter to FN. Do any required
5430 conversions. Return the converted value. */
5432 static GTY(()) VEC(tree,gc) *default_arg_context;
5435 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5440 /* If the ARG is an unparsed default argument expression, the
5441 conversion cannot be performed. */
5442 if (TREE_CODE (arg) == DEFAULT_ARG)
5444 error ("the default argument for parameter %d of %qD has "
5445 "not yet been parsed",
5447 return error_mark_node;
5450 /* Detect recursion. */
5451 FOR_EACH_VEC_ELT (tree, default_arg_context, i, t)
5454 error ("recursive evaluation of default argument for %q#D", fn);
5455 return error_mark_node;
5457 VEC_safe_push (tree, gc, default_arg_context, fn);
5459 if (fn && DECL_TEMPLATE_INFO (fn))
5460 arg = tsubst_default_argument (fn, type, arg);
5466 The names in the expression are bound, and the semantic
5467 constraints are checked, at the point where the default
5468 expressions appears.
5470 we must not perform access checks here. */
5471 push_deferring_access_checks (dk_no_check);
5472 arg = break_out_target_exprs (arg);
5473 if (TREE_CODE (arg) == CONSTRUCTOR)
5475 arg = digest_init (type, arg);
5476 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5477 ICR_DEFAULT_ARGUMENT, fn, parmnum,
5478 tf_warning_or_error);
5482 /* We must make a copy of ARG, in case subsequent processing
5483 alters any part of it. For example, during gimplification a
5484 cast of the form (T) &X::f (where "f" is a member function)
5485 will lead to replacing the PTRMEM_CST for &X::f with a
5486 VAR_DECL. We can avoid the copy for constants, since they
5487 are never modified in place. */
5488 if (!CONSTANT_CLASS_P (arg))
5489 arg = unshare_expr (arg);
5490 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5491 ICR_DEFAULT_ARGUMENT, fn, parmnum,
5492 tf_warning_or_error);
5493 arg = convert_for_arg_passing (type, arg);
5495 pop_deferring_access_checks();
5497 VEC_pop (tree, default_arg_context);
5502 /* Returns the type which will really be used for passing an argument of
5506 type_passed_as (tree type)
5508 /* Pass classes with copy ctors by invisible reference. */
5509 if (TREE_ADDRESSABLE (type))
5511 type = build_reference_type (type);
5512 /* There are no other pointers to this temporary. */
5513 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
5515 else if (targetm.calls.promote_prototypes (type)
5516 && INTEGRAL_TYPE_P (type)
5517 && COMPLETE_TYPE_P (type)
5518 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5519 TYPE_SIZE (integer_type_node)))
5520 type = integer_type_node;
5525 /* Actually perform the appropriate conversion. */
5528 convert_for_arg_passing (tree type, tree val)
5532 /* If VAL is a bitfield, then -- since it has already been converted
5533 to TYPE -- it cannot have a precision greater than TYPE.
5535 If it has a smaller precision, we must widen it here. For
5536 example, passing "int f:3;" to a function expecting an "int" will
5537 not result in any conversion before this point.
5539 If the precision is the same we must not risk widening. For
5540 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5541 often have type "int", even though the C++ type for the field is
5542 "long long". If the value is being passed to a function
5543 expecting an "int", then no conversions will be required. But,
5544 if we call convert_bitfield_to_declared_type, the bitfield will
5545 be converted to "long long". */
5546 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5548 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5549 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5551 if (val == error_mark_node)
5553 /* Pass classes with copy ctors by invisible reference. */
5554 else if (TREE_ADDRESSABLE (type))
5555 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5556 else if (targetm.calls.promote_prototypes (type)
5557 && INTEGRAL_TYPE_P (type)
5558 && COMPLETE_TYPE_P (type)
5559 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5560 TYPE_SIZE (integer_type_node)))
5561 val = perform_integral_promotions (val);
5562 if (warn_missing_format_attribute)
5564 tree rhstype = TREE_TYPE (val);
5565 const enum tree_code coder = TREE_CODE (rhstype);
5566 const enum tree_code codel = TREE_CODE (type);
5567 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5569 && check_missing_format_attribute (type, rhstype))
5570 warning (OPT_Wmissing_format_attribute,
5571 "argument of function call might be a candidate for a format attribute");
5576 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5577 which no conversions at all should be done. This is true for some
5578 builtins which don't act like normal functions. */
5581 magic_varargs_p (tree fn)
5583 if (DECL_BUILT_IN (fn))
5584 switch (DECL_FUNCTION_CODE (fn))
5586 case BUILT_IN_CLASSIFY_TYPE:
5587 case BUILT_IN_CONSTANT_P:
5588 case BUILT_IN_NEXT_ARG:
5589 case BUILT_IN_VA_START:
5593 return lookup_attribute ("type generic",
5594 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5600 /* Subroutine of the various build_*_call functions. Overload resolution
5601 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5602 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5603 bitmask of various LOOKUP_* flags which apply to the call itself. */
5606 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5609 const VEC(tree,gc) *args = cand->args;
5610 tree first_arg = cand->first_arg;
5611 conversion **convs = cand->convs;
5613 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5618 unsigned int arg_index = 0;
5622 bool already_used = false;
5624 /* In a template, there is no need to perform all of the work that
5625 is normally done. We are only interested in the type of the call
5626 expression, i.e., the return type of the function. Any semantic
5627 errors will be deferred until the template is instantiated. */
5628 if (processing_template_decl)
5632 const tree *argarray;
5635 return_type = TREE_TYPE (TREE_TYPE (fn));
5636 nargs = VEC_length (tree, args);
5637 if (first_arg == NULL_TREE)
5638 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5646 alcarray = XALLOCAVEC (tree, nargs);
5647 alcarray[0] = first_arg;
5648 FOR_EACH_VEC_ELT (tree, args, ix, arg)
5649 alcarray[ix + 1] = arg;
5650 argarray = alcarray;
5652 expr = build_call_array_loc (input_location,
5653 return_type, build_addr_func (fn), nargs,
5655 if (TREE_THIS_VOLATILE (fn) && cfun)
5656 current_function_returns_abnormally = 1;
5657 if (!VOID_TYPE_P (return_type))
5658 require_complete_type_sfinae (return_type, complain);
5659 return convert_from_reference (expr);
5662 /* Give any warnings we noticed during overload resolution. */
5663 if (cand->warnings && (complain & tf_warning))
5665 struct candidate_warning *w;
5666 for (w = cand->warnings; w; w = w->next)
5667 joust (cand, w->loser, 1);
5670 /* Make =delete work with SFINAE. */
5671 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5672 return error_mark_node;
5674 if (DECL_FUNCTION_MEMBER_P (fn))
5677 /* If FN is a template function, two cases must be considered.
5682 template <class T> void f();
5684 template <class T> struct B {
5688 struct C : A, B<int> {
5690 using B<int>::g; // #2
5693 In case #1 where `A::f' is a member template, DECL_ACCESS is
5694 recorded in the primary template but not in its specialization.
5695 We check access of FN using its primary template.
5697 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5698 because it is a member of class template B, DECL_ACCESS is
5699 recorded in the specialization `B<int>::g'. We cannot use its
5700 primary template because `B<T>::g' and `B<int>::g' may have
5701 different access. */
5702 if (DECL_TEMPLATE_INFO (fn)
5703 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5704 access_fn = DECL_TI_TEMPLATE (fn);
5707 if (flags & LOOKUP_SPECULATIVE)
5709 /* If we're checking for implicit delete, we don't want access
5711 if (!accessible_p (cand->access_path, access_fn, true))
5713 /* Unless we're under maybe_explain_implicit_delete. */
5714 if (flags & LOOKUP_COMPLAIN)
5715 enforce_access (cand->access_path, access_fn, fn);
5716 return error_mark_node;
5720 perform_or_defer_access_check (cand->access_path, access_fn, fn);
5723 /* If we're checking for implicit delete, don't bother with argument
5725 if (flags & LOOKUP_SPECULATIVE)
5727 if (DECL_DELETED_FN (fn))
5729 if (flags & LOOKUP_COMPLAIN)
5731 return error_mark_node;
5733 if (cand->viable == 1)
5735 else if (!(flags & LOOKUP_COMPLAIN))
5736 /* Reject bad conversions now. */
5737 return error_mark_node;
5738 /* else continue to get conversion error. */
5741 /* Find maximum size of vector to hold converted arguments. */
5742 parmlen = list_length (parm);
5743 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5744 if (parmlen > nargs)
5746 argarray = XALLOCAVEC (tree, nargs);
5748 /* The implicit parameters to a constructor are not considered by overload
5749 resolution, and must be of the proper type. */
5750 if (DECL_CONSTRUCTOR_P (fn))
5752 if (first_arg != NULL_TREE)
5754 argarray[j++] = first_arg;
5755 first_arg = NULL_TREE;
5759 argarray[j++] = VEC_index (tree, args, arg_index);
5762 parm = TREE_CHAIN (parm);
5763 /* We should never try to call the abstract constructor. */
5764 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5766 if (DECL_HAS_VTT_PARM_P (fn))
5768 argarray[j++] = VEC_index (tree, args, arg_index);
5770 parm = TREE_CHAIN (parm);
5773 /* Bypass access control for 'this' parameter. */
5774 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5776 tree parmtype = TREE_VALUE (parm);
5777 tree arg = (first_arg != NULL_TREE
5779 : VEC_index (tree, args, arg_index));
5780 tree argtype = TREE_TYPE (arg);
5784 if (convs[i]->bad_p)
5786 if (complain & tf_error)
5787 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5788 TREE_TYPE (argtype), fn);
5790 return error_mark_node;
5793 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5794 X is called for an object that is not of type X, or of a type
5795 derived from X, the behavior is undefined.
5797 So we can assume that anything passed as 'this' is non-null, and
5798 optimize accordingly. */
5799 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5800 /* Convert to the base in which the function was declared. */
5801 gcc_assert (cand->conversion_path != NULL_TREE);
5802 converted_arg = build_base_path (PLUS_EXPR,
5804 cand->conversion_path,
5806 /* Check that the base class is accessible. */
5807 if (!accessible_base_p (TREE_TYPE (argtype),
5808 BINFO_TYPE (cand->conversion_path), true))
5809 error ("%qT is not an accessible base of %qT",
5810 BINFO_TYPE (cand->conversion_path),
5811 TREE_TYPE (argtype));
5812 /* If fn was found by a using declaration, the conversion path
5813 will be to the derived class, not the base declaring fn. We
5814 must convert from derived to base. */
5815 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5816 TREE_TYPE (parmtype), ba_unique, NULL);
5817 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5820 argarray[j++] = converted_arg;
5821 parm = TREE_CHAIN (parm);
5822 if (first_arg != NULL_TREE)
5823 first_arg = NULL_TREE;
5830 gcc_assert (first_arg == NULL_TREE);
5831 for (; arg_index < VEC_length (tree, args) && parm;
5832 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5834 tree type = TREE_VALUE (parm);
5835 tree arg = VEC_index (tree, args, arg_index);
5839 /* Don't make a copy here if build_call is going to. */
5840 if (conv->kind == ck_rvalue
5841 && COMPLETE_TYPE_P (complete_type (type))
5842 && !TREE_ADDRESSABLE (type))
5843 conv = conv->u.next;
5845 /* Warn about initializer_list deduction that isn't currently in the
5847 if (cxx_dialect > cxx98
5848 && flag_deduce_init_list
5849 && cand->template_decl
5850 && is_std_init_list (non_reference (type))
5851 && BRACE_ENCLOSED_INITIALIZER_P (arg))
5853 tree tmpl = TI_TEMPLATE (cand->template_decl);
5854 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
5855 tree patparm = get_pattern_parm (realparm, tmpl);
5856 tree pattype = TREE_TYPE (patparm);
5857 if (PACK_EXPANSION_P (pattype))
5858 pattype = PACK_EXPANSION_PATTERN (pattype);
5859 pattype = non_reference (pattype);
5861 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
5862 && (cand->explicit_targs == NULL_TREE
5863 || (TREE_VEC_LENGTH (cand->explicit_targs)
5864 <= TEMPLATE_TYPE_IDX (pattype))))
5866 pedwarn (input_location, 0, "deducing %qT as %qT",
5867 non_reference (TREE_TYPE (patparm)),
5868 non_reference (type));
5869 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
5870 pedwarn (input_location, 0,
5871 " (you can disable this with -fno-deduce-init-list)");
5875 val = convert_like_with_context (conv, arg, fn, i-is_method, complain);
5877 val = convert_for_arg_passing (type, val);
5878 if (val == error_mark_node)
5879 return error_mark_node;
5881 argarray[j++] = val;
5884 /* Default arguments */
5885 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5886 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5887 TREE_PURPOSE (parm),
5890 for (; arg_index < VEC_length (tree, args); ++arg_index)
5892 tree a = VEC_index (tree, args, arg_index);
5893 if (magic_varargs_p (fn))
5894 /* Do no conversions for magic varargs. */
5895 a = mark_type_use (a);
5897 a = convert_arg_to_ellipsis (a);
5901 gcc_assert (j <= nargs);
5904 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5905 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5907 /* Avoid actually calling copy constructors and copy assignment operators,
5910 if (! flag_elide_constructors)
5911 /* Do things the hard way. */;
5912 else if (cand->num_convs == 1
5913 && (DECL_COPY_CONSTRUCTOR_P (fn)
5914 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5917 tree arg = argarray[num_artificial_parms_for (fn)];
5919 bool trivial = trivial_fn_p (fn);
5921 /* Pull out the real argument, disregarding const-correctness. */
5923 while (CONVERT_EXPR_P (targ)
5924 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5925 targ = TREE_OPERAND (targ, 0);
5926 if (TREE_CODE (targ) == ADDR_EXPR)
5928 targ = TREE_OPERAND (targ, 0);
5929 if (!same_type_ignoring_top_level_qualifiers_p
5930 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5939 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
5941 if (TREE_CODE (arg) == TARGET_EXPR
5942 && TARGET_EXPR_LIST_INIT_P (arg))
5944 /* Copy-list-initialization doesn't require the constructor
5947 /* [class.copy]: the copy constructor is implicitly defined even if
5948 the implementation elided its use. */
5952 already_used = true;
5955 /* If we're creating a temp and we already have one, don't create a
5956 new one. If we're not creating a temp but we get one, use
5957 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5958 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5959 temp or an INIT_EXPR otherwise. */
5960 fa = (cand->first_arg != NULL_TREE
5962 : VEC_index (tree, args, 0));
5963 if (integer_zerop (fa))
5965 if (TREE_CODE (arg) == TARGET_EXPR)
5968 return force_target_expr (DECL_CONTEXT (fn), arg);
5970 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
5972 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
5975 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5979 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5980 && trivial_fn_p (fn))
5982 tree to = stabilize_reference
5983 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
5984 tree type = TREE_TYPE (to);
5985 tree as_base = CLASSTYPE_AS_BASE (type);
5986 tree arg = argarray[1];
5988 if (is_really_empty_class (type))
5990 /* Avoid copying empty classes. */
5991 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
5992 TREE_NO_WARNING (val) = 1;
5993 val = build2 (COMPOUND_EXPR, type, val, to);
5994 TREE_NO_WARNING (val) = 1;
5996 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5998 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
5999 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
6003 /* We must only copy the non-tail padding parts.
6004 Use __builtin_memcpy for the bitwise copy.
6005 FIXME fix 22488 so we can go back to using MODIFY_EXPR
6006 instead of an explicit call to memcpy. */
6008 tree arg0, arg1, arg2, t;
6009 tree test = NULL_TREE;
6011 arg2 = TYPE_SIZE_UNIT (as_base);
6013 arg0 = cp_build_addr_expr (to, complain);
6015 if (!can_trust_pointer_alignment ())
6017 /* If we can't be sure about pointer alignment, a call
6018 to __builtin_memcpy is expanded as a call to memcpy, which
6019 is invalid with identical args. Otherwise it is
6020 expanded as a block move, which should be safe. */
6021 arg0 = save_expr (arg0);
6022 arg1 = save_expr (arg1);
6023 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
6025 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
6026 t = build_call_n (t, 3, arg0, arg1, arg2);
6028 t = convert (TREE_TYPE (arg0), t);
6030 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
6031 val = cp_build_indirect_ref (t, RO_NULL, complain);
6032 TREE_NO_WARNING (val) = 1;
6041 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
6044 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
6047 gcc_assert (binfo && binfo != error_mark_node);
6049 /* Warn about deprecated virtual functions now, since we're about
6050 to throw away the decl. */
6051 if (TREE_DEPRECATED (fn))
6052 warn_deprecated_use (fn, NULL_TREE);
6054 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
6055 if (TREE_SIDE_EFFECTS (argarray[0]))
6056 argarray[0] = save_expr (argarray[0]);
6057 t = build_pointer_type (TREE_TYPE (fn));
6058 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
6059 fn = build_java_interface_fn_ref (fn, argarray[0]);
6061 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
6065 fn = build_addr_func (fn);
6067 return build_cxx_call (fn, nargs, argarray);
6070 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
6071 This function performs no overload resolution, conversion, or other
6072 high-level operations. */
6075 build_cxx_call (tree fn, int nargs, tree *argarray)
6079 fn = build_call_a (fn, nargs, argarray);
6081 /* If this call might throw an exception, note that fact. */
6082 fndecl = get_callee_fndecl (fn);
6083 if ((!fndecl || !TREE_NOTHROW (fndecl))
6084 && at_function_scope_p ()
6086 cp_function_chain->can_throw = 1;
6088 /* Check that arguments to builtin functions match the expectations. */
6090 && DECL_BUILT_IN (fndecl)
6091 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6092 && !check_builtin_function_arguments (fndecl, nargs, argarray))
6093 return error_mark_node;
6095 /* Some built-in function calls will be evaluated at compile-time in
6097 fn = fold_if_not_in_template (fn);
6099 if (VOID_TYPE_P (TREE_TYPE (fn)))
6102 fn = require_complete_type (fn);
6103 if (fn == error_mark_node)
6104 return error_mark_node;
6106 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
6107 fn = build_cplus_new (TREE_TYPE (fn), fn);
6108 return convert_from_reference (fn);
6111 static GTY(()) tree java_iface_lookup_fn;
6113 /* Make an expression which yields the address of the Java interface
6114 method FN. This is achieved by generating a call to libjava's
6115 _Jv_LookupInterfaceMethodIdx(). */
6118 build_java_interface_fn_ref (tree fn, tree instance)
6120 tree lookup_fn, method, idx;
6121 tree klass_ref, iface, iface_ref;
6124 if (!java_iface_lookup_fn)
6126 tree ftype = build_function_type_list (ptr_type_node,
6127 ptr_type_node, ptr_type_node,
6128 java_int_type_node, NULL_TREE);
6129 java_iface_lookup_fn
6130 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
6131 0, NOT_BUILT_IN, NULL, NULL_TREE);
6134 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
6135 This is the first entry in the vtable. */
6136 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
6137 tf_warning_or_error),
6140 /* Get the java.lang.Class pointer for the interface being called. */
6141 iface = DECL_CONTEXT (fn);
6142 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
6143 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
6144 || DECL_CONTEXT (iface_ref) != iface)
6146 error ("could not find class$ field in java interface type %qT",
6148 return error_mark_node;
6150 iface_ref = build_address (iface_ref);
6151 iface_ref = convert (build_pointer_type (iface), iface_ref);
6153 /* Determine the itable index of FN. */
6155 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
6157 if (!DECL_VIRTUAL_P (method))
6163 idx = build_int_cst (NULL_TREE, i);
6165 lookup_fn = build1 (ADDR_EXPR,
6166 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
6167 java_iface_lookup_fn);
6168 return build_call_nary (ptr_type_node, lookup_fn,
6169 3, klass_ref, iface_ref, idx);
6172 /* Returns the value to use for the in-charge parameter when making a
6173 call to a function with the indicated NAME.
6175 FIXME:Can't we find a neater way to do this mapping? */
6178 in_charge_arg_for_name (tree name)
6180 if (name == base_ctor_identifier
6181 || name == base_dtor_identifier)
6182 return integer_zero_node;
6183 else if (name == complete_ctor_identifier)
6184 return integer_one_node;
6185 else if (name == complete_dtor_identifier)
6186 return integer_two_node;
6187 else if (name == deleting_dtor_identifier)
6188 return integer_three_node;
6190 /* This function should only be called with one of the names listed
6196 /* Build a call to a constructor, destructor, or an assignment
6197 operator for INSTANCE, an expression with class type. NAME
6198 indicates the special member function to call; *ARGS are the
6199 arguments. ARGS may be NULL. This may change ARGS. BINFO
6200 indicates the base of INSTANCE that is to be passed as the `this'
6201 parameter to the member function called.
6203 FLAGS are the LOOKUP_* flags to use when processing the call.
6205 If NAME indicates a complete object constructor, INSTANCE may be
6206 NULL_TREE. In this case, the caller will call build_cplus_new to
6207 store the newly constructed object into a VAR_DECL. */
6210 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6211 tree binfo, int flags, tsubst_flags_t complain)
6214 /* The type of the subobject to be constructed or destroyed. */
6216 VEC(tree,gc) *allocated = NULL;
6219 gcc_assert (name == complete_ctor_identifier
6220 || name == base_ctor_identifier
6221 || name == complete_dtor_identifier
6222 || name == base_dtor_identifier
6223 || name == deleting_dtor_identifier
6224 || name == ansi_assopname (NOP_EXPR));
6227 /* Resolve the name. */
6228 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
6229 return error_mark_node;
6231 binfo = TYPE_BINFO (binfo);
6234 gcc_assert (binfo != NULL_TREE);
6236 class_type = BINFO_TYPE (binfo);
6238 /* Handle the special case where INSTANCE is NULL_TREE. */
6239 if (name == complete_ctor_identifier && !instance)
6241 instance = build_int_cst (build_pointer_type (class_type), 0);
6242 instance = build1 (INDIRECT_REF, class_type, instance);
6246 if (name == complete_dtor_identifier
6247 || name == base_dtor_identifier
6248 || name == deleting_dtor_identifier)
6249 gcc_assert (args == NULL || VEC_empty (tree, *args));
6251 /* Convert to the base class, if necessary. */
6252 if (!same_type_ignoring_top_level_qualifiers_p
6253 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6255 if (name != ansi_assopname (NOP_EXPR))
6256 /* For constructors and destructors, either the base is
6257 non-virtual, or it is virtual but we are doing the
6258 conversion from a constructor or destructor for the
6259 complete object. In either case, we can convert
6261 instance = convert_to_base_statically (instance, binfo);
6263 /* However, for assignment operators, we must convert
6264 dynamically if the base is virtual. */
6265 instance = build_base_path (PLUS_EXPR, instance,
6266 binfo, /*nonnull=*/1);
6270 gcc_assert (instance != NULL_TREE);
6272 fns = lookup_fnfields (binfo, name, 1);
6274 /* When making a call to a constructor or destructor for a subobject
6275 that uses virtual base classes, pass down a pointer to a VTT for
6277 if ((name == base_ctor_identifier
6278 || name == base_dtor_identifier)
6279 && CLASSTYPE_VBASECLASSES (class_type))
6284 /* If the current function is a complete object constructor
6285 or destructor, then we fetch the VTT directly.
6286 Otherwise, we look it up using the VTT we were given. */
6287 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6288 vtt = decay_conversion (vtt);
6289 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6290 build2 (EQ_EXPR, boolean_type_node,
6291 current_in_charge_parm, integer_zero_node),
6294 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6295 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6296 BINFO_SUBVTT_INDEX (binfo));
6300 allocated = make_tree_vector ();
6304 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6307 ret = build_new_method_call (instance, fns, args,
6308 TYPE_BINFO (BINFO_TYPE (binfo)),
6312 if (allocated != NULL)
6313 release_tree_vector (allocated);
6318 /* Return the NAME, as a C string. The NAME indicates a function that
6319 is a member of TYPE. *FREE_P is set to true if the caller must
6320 free the memory returned.
6322 Rather than go through all of this, we should simply set the names
6323 of constructors and destructors appropriately, and dispense with
6324 ctor_identifier, dtor_identifier, etc. */
6327 name_as_c_string (tree name, tree type, bool *free_p)
6331 /* Assume that we will not allocate memory. */
6333 /* Constructors and destructors are special. */
6334 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6337 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6338 /* For a destructor, add the '~'. */
6339 if (name == complete_dtor_identifier
6340 || name == base_dtor_identifier
6341 || name == deleting_dtor_identifier)
6343 pretty_name = concat ("~", pretty_name, NULL);
6344 /* Remember that we need to free the memory allocated. */
6348 else if (IDENTIFIER_TYPENAME_P (name))
6350 pretty_name = concat ("operator ",
6351 type_as_string_translate (TREE_TYPE (name),
6352 TFF_PLAIN_IDENTIFIER),
6354 /* Remember that we need to free the memory allocated. */
6358 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6363 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6364 be set, upon return, to the function called. ARGS may be NULL.
6365 This may change ARGS. */
6368 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6369 tree conversion_path, int flags,
6370 tree *fn_p, tsubst_flags_t complain)
6372 struct z_candidate *candidates = 0, *cand;
6373 tree explicit_targs = NULL_TREE;
6374 tree basetype = NULL_TREE;
6377 tree first_mem_arg = NULL_TREE;
6380 bool skip_first_for_error;
6381 VEC(tree,gc) *user_args;
6384 int template_only = 0;
6388 VEC(tree,gc) *orig_args = NULL;
6391 gcc_assert (instance != NULL_TREE);
6393 /* We don't know what function we're going to call, yet. */
6397 if (error_operand_p (instance)
6398 || !fns || error_operand_p (fns))
6399 return error_mark_node;
6401 if (!BASELINK_P (fns))
6403 if (complain & tf_error)
6404 error ("call to non-function %qD", fns);
6405 return error_mark_node;
6408 orig_instance = instance;
6411 /* Dismantle the baselink to collect all the information we need. */
6412 if (!conversion_path)
6413 conversion_path = BASELINK_BINFO (fns);
6414 access_binfo = BASELINK_ACCESS_BINFO (fns);
6415 optype = BASELINK_OPTYPE (fns);
6416 fns = BASELINK_FUNCTIONS (fns);
6417 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6419 explicit_targs = TREE_OPERAND (fns, 1);
6420 fns = TREE_OPERAND (fns, 0);
6423 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6424 || TREE_CODE (fns) == TEMPLATE_DECL
6425 || TREE_CODE (fns) == OVERLOAD);
6426 fn = get_first_fn (fns);
6427 name = DECL_NAME (fn);
6429 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6430 gcc_assert (CLASS_TYPE_P (basetype));
6432 if (processing_template_decl)
6434 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6435 instance = build_non_dependent_expr (instance);
6437 make_args_non_dependent (*args);
6440 user_args = args == NULL ? NULL : *args;
6441 /* Under DR 147 A::A() is an invalid constructor call,
6442 not a functional cast. */
6443 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
6445 if (! (complain & tf_error))
6446 return error_mark_node;
6448 permerror (input_location,
6449 "cannot call constructor %<%T::%D%> directly",
6451 permerror (input_location, " for a function-style cast, remove the "
6452 "redundant %<::%D%>", name);
6453 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
6458 /* Figure out whether to skip the first argument for the error
6459 message we will display to users if an error occurs. We don't
6460 want to display any compiler-generated arguments. The "this"
6461 pointer hasn't been added yet. However, we must remove the VTT
6462 pointer if this is a call to a base-class constructor or
6464 skip_first_for_error = false;
6465 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6467 /* Callers should explicitly indicate whether they want to construct
6468 the complete object or just the part without virtual bases. */
6469 gcc_assert (name != ctor_identifier);
6470 /* Similarly for destructors. */
6471 gcc_assert (name != dtor_identifier);
6472 /* Remove the VTT pointer, if present. */
6473 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6474 && CLASSTYPE_VBASECLASSES (basetype))
6475 skip_first_for_error = true;
6478 /* Process the argument list. */
6479 if (args != NULL && *args != NULL)
6481 *args = resolve_args (*args);
6483 return error_mark_node;
6486 instance_ptr = build_this (instance);
6488 /* It's OK to call destructors and constructors on cv-qualified objects.
6489 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6491 if (DECL_DESTRUCTOR_P (fn)
6492 || DECL_CONSTRUCTOR_P (fn))
6494 tree type = build_pointer_type (basetype);
6495 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6496 instance_ptr = build_nop (type, instance_ptr);
6498 if (DECL_DESTRUCTOR_P (fn))
6499 name = complete_dtor_identifier;
6501 first_mem_arg = instance_ptr;
6503 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6504 p = conversion_obstack_alloc (0);
6506 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6507 initializer, not T({ }). */
6508 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6509 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6510 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0)))
6512 gcc_assert (VEC_length (tree, *args) == 1
6513 && !(flags & LOOKUP_ONLYCONVERTING));
6515 add_list_candidates (fns, first_mem_arg, VEC_index (tree, *args, 0),
6516 basetype, explicit_targs, template_only,
6517 conversion_path, access_binfo, flags, &candidates);
6521 add_candidates (fns, first_mem_arg, user_args, optype,
6522 explicit_targs, template_only, conversion_path,
6523 access_binfo, flags, &candidates);
6525 any_viable_p = false;
6526 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6530 if (complain & tf_error)
6532 if (!COMPLETE_TYPE_P (basetype))
6533 cxx_incomplete_type_error (instance_ptr, basetype);
6535 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
6536 basetype, optype, build_tree_list_vec (user_args),
6537 TREE_TYPE (TREE_TYPE (instance_ptr)));
6544 pretty_name = name_as_c_string (name, basetype, &free_p);
6545 arglist = build_tree_list_vec (user_args);
6546 if (skip_first_for_error)
6547 arglist = TREE_CHAIN (arglist);
6548 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6549 basetype, pretty_name, arglist,
6550 TREE_TYPE (TREE_TYPE (instance_ptr)));
6554 print_z_candidates (candidates);
6556 call = error_mark_node;
6560 cand = tourney (candidates);
6567 if (complain & tf_error)
6569 pretty_name = name_as_c_string (name, basetype, &free_p);
6570 arglist = build_tree_list_vec (user_args);
6571 if (skip_first_for_error)
6572 arglist = TREE_CHAIN (arglist);
6573 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6575 print_z_candidates (candidates);
6579 call = error_mark_node;
6585 if (!(flags & LOOKUP_NONVIRTUAL)
6586 && DECL_PURE_VIRTUAL_P (fn)
6587 && instance == current_class_ref
6588 && (DECL_CONSTRUCTOR_P (current_function_decl)
6589 || DECL_DESTRUCTOR_P (current_function_decl))
6590 && (complain & tf_warning))
6591 /* This is not an error, it is runtime undefined
6593 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6594 "pure virtual %q#D called from constructor"
6595 : "pure virtual %q#D called from destructor"),
6598 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6599 && is_dummy_object (instance_ptr))
6601 if (complain & tf_error)
6602 error ("cannot call member function %qD without object",
6604 call = error_mark_node;
6608 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6609 && resolves_to_fixed_type_p (instance, 0))
6610 flags |= LOOKUP_NONVIRTUAL;
6611 /* Now we know what function is being called. */
6614 /* Build the actual CALL_EXPR. */
6615 call = build_over_call (cand, flags, complain);
6616 /* In an expression of the form `a->f()' where `f' turns
6617 out to be a static member function, `a' is
6618 none-the-less evaluated. */
6619 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6620 && !is_dummy_object (instance_ptr)
6621 && TREE_SIDE_EFFECTS (instance_ptr))
6622 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6623 instance_ptr, call);
6624 else if (call != error_mark_node
6625 && DECL_DESTRUCTOR_P (cand->fn)
6626 && !VOID_TYPE_P (TREE_TYPE (call)))
6627 /* An explicit call of the form "x->~X()" has type
6628 "void". However, on platforms where destructors
6629 return "this" (i.e., those where
6630 targetm.cxx.cdtor_returns_this is true), such calls
6631 will appear to have a return value of pointer type
6632 to the low-level call machinery. We do not want to
6633 change the low-level machinery, since we want to be
6634 able to optimize "delete f()" on such platforms as
6635 "operator delete(~X(f()))" (rather than generating
6636 "t = f(), ~X(t), operator delete (t)"). */
6637 call = build_nop (void_type_node, call);
6642 if (processing_template_decl && call != error_mark_node)
6644 bool cast_to_void = false;
6646 if (TREE_CODE (call) == COMPOUND_EXPR)
6647 call = TREE_OPERAND (call, 1);
6648 else if (TREE_CODE (call) == NOP_EXPR)
6650 cast_to_void = true;
6651 call = TREE_OPERAND (call, 0);
6653 if (TREE_CODE (call) == INDIRECT_REF)
6654 call = TREE_OPERAND (call, 0);
6655 call = (build_min_non_dep_call_vec
6657 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6658 orig_instance, orig_fns, NULL_TREE),
6660 call = convert_from_reference (call);
6662 call = build_nop (void_type_node, call);
6665 /* Free all the conversions we allocated. */
6666 obstack_free (&conversion_obstack, p);
6668 if (orig_args != NULL)
6669 release_tree_vector (orig_args);
6674 /* Returns true iff standard conversion sequence ICS1 is a proper
6675 subsequence of ICS2. */
6678 is_subseq (conversion *ics1, conversion *ics2)
6680 /* We can assume that a conversion of the same code
6681 between the same types indicates a subsequence since we only get
6682 here if the types we are converting from are the same. */
6684 while (ics1->kind == ck_rvalue
6685 || ics1->kind == ck_lvalue)
6686 ics1 = ics1->u.next;
6690 while (ics2->kind == ck_rvalue
6691 || ics2->kind == ck_lvalue)
6692 ics2 = ics2->u.next;
6694 if (ics2->kind == ck_user
6695 || ics2->kind == ck_ambig
6696 || ics2->kind == ck_aggr
6697 || ics2->kind == ck_list
6698 || ics2->kind == ck_identity)
6699 /* At this point, ICS1 cannot be a proper subsequence of
6700 ICS2. We can get a USER_CONV when we are comparing the
6701 second standard conversion sequence of two user conversion
6705 ics2 = ics2->u.next;
6707 if (ics2->kind == ics1->kind
6708 && same_type_p (ics2->type, ics1->type)
6709 && same_type_p (ics2->u.next->type,
6710 ics1->u.next->type))
6715 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6716 be any _TYPE nodes. */
6719 is_properly_derived_from (tree derived, tree base)
6721 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6724 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6725 considers every class derived from itself. */
6726 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6727 && DERIVED_FROM_P (base, derived));
6730 /* We build the ICS for an implicit object parameter as a pointer
6731 conversion sequence. However, such a sequence should be compared
6732 as if it were a reference conversion sequence. If ICS is the
6733 implicit conversion sequence for an implicit object parameter,
6734 modify it accordingly. */
6737 maybe_handle_implicit_object (conversion **ics)
6741 /* [over.match.funcs]
6743 For non-static member functions, the type of the
6744 implicit object parameter is "reference to cv X"
6745 where X is the class of which the function is a
6746 member and cv is the cv-qualification on the member
6747 function declaration. */
6748 conversion *t = *ics;
6749 tree reference_type;
6751 /* The `this' parameter is a pointer to a class type. Make the
6752 implicit conversion talk about a reference to that same class
6754 reference_type = TREE_TYPE (t->type);
6755 reference_type = build_reference_type (reference_type);
6757 if (t->kind == ck_qual)
6759 if (t->kind == ck_ptr)
6761 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6762 t = direct_reference_binding (reference_type, t);
6764 t->rvaluedness_matches_p = 0;
6769 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6770 and return the initial reference binding conversion. Otherwise,
6771 leave *ICS unchanged and return NULL. */
6774 maybe_handle_ref_bind (conversion **ics)
6776 if ((*ics)->kind == ck_ref_bind)
6778 conversion *old_ics = *ics;
6779 *ics = old_ics->u.next;
6780 (*ics)->user_conv_p = old_ics->user_conv_p;
6787 /* Compare two implicit conversion sequences according to the rules set out in
6788 [over.ics.rank]. Return values:
6790 1: ics1 is better than ics2
6791 -1: ics2 is better than ics1
6792 0: ics1 and ics2 are indistinguishable */
6795 compare_ics (conversion *ics1, conversion *ics2)
6801 tree deref_from_type1 = NULL_TREE;
6802 tree deref_from_type2 = NULL_TREE;
6803 tree deref_to_type1 = NULL_TREE;
6804 tree deref_to_type2 = NULL_TREE;
6805 conversion_rank rank1, rank2;
6807 /* REF_BINDING is nonzero if the result of the conversion sequence
6808 is a reference type. In that case REF_CONV is the reference
6809 binding conversion. */
6810 conversion *ref_conv1;
6811 conversion *ref_conv2;
6813 /* Handle implicit object parameters. */
6814 maybe_handle_implicit_object (&ics1);
6815 maybe_handle_implicit_object (&ics2);
6817 /* Handle reference parameters. */
6818 ref_conv1 = maybe_handle_ref_bind (&ics1);
6819 ref_conv2 = maybe_handle_ref_bind (&ics2);
6821 /* List-initialization sequence L1 is a better conversion sequence than
6822 list-initialization sequence L2 if L1 converts to
6823 std::initializer_list<X> for some X and L2 does not. */
6824 if (ics1->kind == ck_list && ics2->kind != ck_list)
6826 if (ics2->kind == ck_list && ics1->kind != ck_list)
6831 When comparing the basic forms of implicit conversion sequences (as
6832 defined in _over.best.ics_)
6834 --a standard conversion sequence (_over.ics.scs_) is a better
6835 conversion sequence than a user-defined conversion sequence
6836 or an ellipsis conversion sequence, and
6838 --a user-defined conversion sequence (_over.ics.user_) is a
6839 better conversion sequence than an ellipsis conversion sequence
6840 (_over.ics.ellipsis_). */
6841 rank1 = CONVERSION_RANK (ics1);
6842 rank2 = CONVERSION_RANK (ics2);
6846 else if (rank1 < rank2)
6849 if (rank1 == cr_bad)
6851 /* Both ICS are bad. We try to make a decision based on what would
6852 have happened if they'd been good. This is not an extension,
6853 we'll still give an error when we build up the call; this just
6854 helps us give a more helpful error message. */
6855 rank1 = BAD_CONVERSION_RANK (ics1);
6856 rank2 = BAD_CONVERSION_RANK (ics2);
6860 else if (rank1 < rank2)
6863 /* We couldn't make up our minds; try to figure it out below. */
6866 if (ics1->ellipsis_p)
6867 /* Both conversions are ellipsis conversions. */
6870 /* User-defined conversion sequence U1 is a better conversion sequence
6871 than another user-defined conversion sequence U2 if they contain the
6872 same user-defined conversion operator or constructor and if the sec-
6873 ond standard conversion sequence of U1 is better than the second
6874 standard conversion sequence of U2. */
6876 /* Handle list-conversion with the same code even though it isn't always
6877 ranked as a user-defined conversion and it doesn't have a second
6878 standard conversion sequence; it will still have the desired effect.
6879 Specifically, we need to do the reference binding comparison at the
6880 end of this function. */
6882 if (ics1->user_conv_p || ics1->kind == ck_list)
6887 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6888 if (t1->kind == ck_ambig || t1->kind == ck_aggr
6889 || t1->kind == ck_list)
6891 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6892 if (t2->kind == ck_ambig || t2->kind == ck_aggr
6893 || t2->kind == ck_list)
6896 if (t1->kind != t2->kind)
6898 else if (t1->kind == ck_user)
6900 if (t1->cand->fn != t2->cand->fn)
6905 /* For ambiguous or aggregate conversions, use the target type as
6906 a proxy for the conversion function. */
6907 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
6911 /* We can just fall through here, after setting up
6912 FROM_TYPE1 and FROM_TYPE2. */
6913 from_type1 = t1->type;
6914 from_type2 = t2->type;
6921 /* We're dealing with two standard conversion sequences.
6925 Standard conversion sequence S1 is a better conversion
6926 sequence than standard conversion sequence S2 if
6928 --S1 is a proper subsequence of S2 (comparing the conversion
6929 sequences in the canonical form defined by _over.ics.scs_,
6930 excluding any Lvalue Transformation; the identity
6931 conversion sequence is considered to be a subsequence of
6932 any non-identity conversion sequence */
6935 while (t1->kind != ck_identity)
6937 from_type1 = t1->type;
6940 while (t2->kind != ck_identity)
6942 from_type2 = t2->type;
6945 /* One sequence can only be a subsequence of the other if they start with
6946 the same type. They can start with different types when comparing the
6947 second standard conversion sequence in two user-defined conversion
6949 if (same_type_p (from_type1, from_type2))
6951 if (is_subseq (ics1, ics2))
6953 if (is_subseq (ics2, ics1))
6961 --the rank of S1 is better than the rank of S2 (by the rules
6964 Standard conversion sequences are ordered by their ranks: an Exact
6965 Match is a better conversion than a Promotion, which is a better
6966 conversion than a Conversion.
6968 Two conversion sequences with the same rank are indistinguishable
6969 unless one of the following rules applies:
6971 --A conversion that does not a convert a pointer, pointer to member,
6972 or std::nullptr_t to bool is better than one that does.
6974 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6975 so that we do not have to check it explicitly. */
6976 if (ics1->rank < ics2->rank)
6978 else if (ics2->rank < ics1->rank)
6981 to_type1 = ics1->type;
6982 to_type2 = ics2->type;
6984 /* A conversion from scalar arithmetic type to complex is worse than a
6985 conversion between scalar arithmetic types. */
6986 if (same_type_p (from_type1, from_type2)
6987 && ARITHMETIC_TYPE_P (from_type1)
6988 && ARITHMETIC_TYPE_P (to_type1)
6989 && ARITHMETIC_TYPE_P (to_type2)
6990 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6991 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6993 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6999 if (TYPE_PTR_P (from_type1)
7000 && TYPE_PTR_P (from_type2)
7001 && TYPE_PTR_P (to_type1)
7002 && TYPE_PTR_P (to_type2))
7004 deref_from_type1 = TREE_TYPE (from_type1);
7005 deref_from_type2 = TREE_TYPE (from_type2);
7006 deref_to_type1 = TREE_TYPE (to_type1);
7007 deref_to_type2 = TREE_TYPE (to_type2);
7009 /* The rules for pointers to members A::* are just like the rules
7010 for pointers A*, except opposite: if B is derived from A then
7011 A::* converts to B::*, not vice versa. For that reason, we
7012 switch the from_ and to_ variables here. */
7013 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
7014 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
7015 || (TYPE_PTRMEMFUNC_P (from_type1)
7016 && TYPE_PTRMEMFUNC_P (from_type2)
7017 && TYPE_PTRMEMFUNC_P (to_type1)
7018 && TYPE_PTRMEMFUNC_P (to_type2)))
7020 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
7021 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
7022 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
7023 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
7026 if (deref_from_type1 != NULL_TREE
7027 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
7028 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
7030 /* This was one of the pointer or pointer-like conversions.
7034 --If class B is derived directly or indirectly from class A,
7035 conversion of B* to A* is better than conversion of B* to
7036 void*, and conversion of A* to void* is better than
7037 conversion of B* to void*. */
7038 if (TREE_CODE (deref_to_type1) == VOID_TYPE
7039 && TREE_CODE (deref_to_type2) == VOID_TYPE)
7041 if (is_properly_derived_from (deref_from_type1,
7044 else if (is_properly_derived_from (deref_from_type2,
7048 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
7049 || TREE_CODE (deref_to_type2) == VOID_TYPE)
7051 if (same_type_p (deref_from_type1, deref_from_type2))
7053 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
7055 if (is_properly_derived_from (deref_from_type1,
7059 /* We know that DEREF_TO_TYPE1 is `void' here. */
7060 else if (is_properly_derived_from (deref_from_type1,
7065 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
7066 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
7070 --If class B is derived directly or indirectly from class A
7071 and class C is derived directly or indirectly from B,
7073 --conversion of C* to B* is better than conversion of C* to
7076 --conversion of B* to A* is better than conversion of C* to
7078 if (same_type_p (deref_from_type1, deref_from_type2))
7080 if (is_properly_derived_from (deref_to_type1,
7083 else if (is_properly_derived_from (deref_to_type2,
7087 else if (same_type_p (deref_to_type1, deref_to_type2))
7089 if (is_properly_derived_from (deref_from_type2,
7092 else if (is_properly_derived_from (deref_from_type1,
7098 else if (CLASS_TYPE_P (non_reference (from_type1))
7099 && same_type_p (from_type1, from_type2))
7101 tree from = non_reference (from_type1);
7105 --binding of an expression of type C to a reference of type
7106 B& is better than binding an expression of type C to a
7107 reference of type A&
7109 --conversion of C to B is better than conversion of C to A, */
7110 if (is_properly_derived_from (from, to_type1)
7111 && is_properly_derived_from (from, to_type2))
7113 if (is_properly_derived_from (to_type1, to_type2))
7115 else if (is_properly_derived_from (to_type2, to_type1))
7119 else if (CLASS_TYPE_P (non_reference (to_type1))
7120 && same_type_p (to_type1, to_type2))
7122 tree to = non_reference (to_type1);
7126 --binding of an expression of type B to a reference of type
7127 A& is better than binding an expression of type C to a
7128 reference of type A&,
7130 --conversion of B to A is better than conversion of C to A */
7131 if (is_properly_derived_from (from_type1, to)
7132 && is_properly_derived_from (from_type2, to))
7134 if (is_properly_derived_from (from_type2, from_type1))
7136 else if (is_properly_derived_from (from_type1, from_type2))
7143 --S1 and S2 differ only in their qualification conversion and yield
7144 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
7145 qualification signature of type T1 is a proper subset of the cv-
7146 qualification signature of type T2 */
7147 if (ics1->kind == ck_qual
7148 && ics2->kind == ck_qual
7149 && same_type_p (from_type1, from_type2))
7151 int result = comp_cv_qual_signature (to_type1, to_type2);
7158 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
7159 to an implicit object parameter, and either S1 binds an lvalue reference
7160 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
7161 reference to an rvalue and S2 binds an lvalue reference
7162 (C++0x draft standard, 13.3.3.2)
7164 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
7165 types to which the references refer are the same type except for
7166 top-level cv-qualifiers, and the type to which the reference
7167 initialized by S2 refers is more cv-qualified than the type to
7168 which the reference initialized by S1 refers */
7170 if (ref_conv1 && ref_conv2)
7172 if (!ref_conv1->this_p && !ref_conv2->this_p
7173 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
7174 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
7176 if (ref_conv1->rvaluedness_matches_p)
7178 if (ref_conv2->rvaluedness_matches_p)
7182 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7183 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7184 TREE_TYPE (ref_conv1->type));
7187 /* Neither conversion sequence is better than the other. */
7191 /* The source type for this standard conversion sequence. */
7194 source_type (conversion *t)
7196 for (;; t = t->u.next)
7198 if (t->kind == ck_user
7199 || t->kind == ck_ambig
7200 || t->kind == ck_identity)
7206 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7207 a pointer to LOSER and re-running joust to produce the warning if WINNER
7208 is actually used. */
7211 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7213 candidate_warning *cw = (candidate_warning *)
7214 conversion_obstack_alloc (sizeof (candidate_warning));
7216 cw->next = winner->warnings;
7217 winner->warnings = cw;
7220 /* Compare two candidates for overloading as described in
7221 [over.match.best]. Return values:
7223 1: cand1 is better than cand2
7224 -1: cand2 is better than cand1
7225 0: cand1 and cand2 are indistinguishable */
7228 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7231 int off1 = 0, off2 = 0;
7235 /* Candidates that involve bad conversions are always worse than those
7237 if (cand1->viable > cand2->viable)
7239 if (cand1->viable < cand2->viable)
7242 /* If we have two pseudo-candidates for conversions to the same type,
7243 or two candidates for the same function, arbitrarily pick one. */
7244 if (cand1->fn == cand2->fn
7245 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7248 /* a viable function F1
7249 is defined to be a better function than another viable function F2 if
7250 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7251 ICSi(F2), and then */
7253 /* for some argument j, ICSj(F1) is a better conversion sequence than
7256 /* For comparing static and non-static member functions, we ignore
7257 the implicit object parameter of the non-static function. The
7258 standard says to pretend that the static function has an object
7259 parm, but that won't work with operator overloading. */
7260 len = cand1->num_convs;
7261 if (len != cand2->num_convs)
7263 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7264 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7266 gcc_assert (static_1 != static_2);
7277 for (i = 0; i < len; ++i)
7279 conversion *t1 = cand1->convs[i + off1];
7280 conversion *t2 = cand2->convs[i + off2];
7281 int comp = compare_ics (t1, t2);
7286 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7287 == cr_std + cr_promotion)
7288 && t1->kind == ck_std
7289 && t2->kind == ck_std
7290 && TREE_CODE (t1->type) == INTEGER_TYPE
7291 && TREE_CODE (t2->type) == INTEGER_TYPE
7292 && (TYPE_PRECISION (t1->type)
7293 == TYPE_PRECISION (t2->type))
7294 && (TYPE_UNSIGNED (t1->u.next->type)
7295 || (TREE_CODE (t1->u.next->type)
7298 tree type = t1->u.next->type;
7300 struct z_candidate *w, *l;
7302 type1 = t1->type, type2 = t2->type,
7303 w = cand1, l = cand2;
7305 type1 = t2->type, type2 = t1->type,
7306 w = cand2, l = cand1;
7310 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7311 type, type1, type2);
7312 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7318 if (winner && comp != winner)
7327 /* warn about confusing overload resolution for user-defined conversions,
7328 either between a constructor and a conversion op, or between two
7330 if (winner && warn_conversion && cand1->second_conv
7331 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7332 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7334 struct z_candidate *w, *l;
7335 bool give_warning = false;
7338 w = cand1, l = cand2;
7340 w = cand2, l = cand1;
7342 /* We don't want to complain about `X::operator T1 ()'
7343 beating `X::operator T2 () const', when T2 is a no less
7344 cv-qualified version of T1. */
7345 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7346 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7348 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7349 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7351 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7356 if (!comp_ptr_ttypes (t, f))
7357 give_warning = true;
7360 give_warning = true;
7366 tree source = source_type (w->convs[0]);
7367 if (! DECL_CONSTRUCTOR_P (w->fn))
7368 source = TREE_TYPE (source);
7369 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7370 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7371 source, w->second_conv->type))
7373 inform (input_location, " because conversion sequence for the argument is better");
7384 F1 is a non-template function and F2 is a template function
7387 if (!cand1->template_decl && cand2->template_decl)
7389 else if (cand1->template_decl && !cand2->template_decl)
7393 F1 and F2 are template functions and the function template for F1 is
7394 more specialized than the template for F2 according to the partial
7397 if (cand1->template_decl && cand2->template_decl)
7399 winner = more_specialized_fn
7400 (TI_TEMPLATE (cand1->template_decl),
7401 TI_TEMPLATE (cand2->template_decl),
7402 /* [temp.func.order]: The presence of unused ellipsis and default
7403 arguments has no effect on the partial ordering of function
7404 templates. add_function_candidate() will not have
7405 counted the "this" argument for constructors. */
7406 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7412 the context is an initialization by user-defined conversion (see
7413 _dcl.init_ and _over.match.user_) and the standard conversion
7414 sequence from the return type of F1 to the destination type (i.e.,
7415 the type of the entity being initialized) is a better conversion
7416 sequence than the standard conversion sequence from the return type
7417 of F2 to the destination type. */
7419 if (cand1->second_conv)
7421 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7426 /* Check whether we can discard a builtin candidate, either because we
7427 have two identical ones or matching builtin and non-builtin candidates.
7429 (Pedantically in the latter case the builtin which matched the user
7430 function should not be added to the overload set, but we spot it here.
7433 ... the builtin candidates include ...
7434 - do not have the same parameter type list as any non-template
7435 non-member candidate. */
7437 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7438 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7440 for (i = 0; i < len; ++i)
7441 if (!same_type_p (cand1->convs[i]->type,
7442 cand2->convs[i]->type))
7444 if (i == cand1->num_convs)
7446 if (cand1->fn == cand2->fn)
7447 /* Two built-in candidates; arbitrarily pick one. */
7449 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7450 /* cand1 is built-in; prefer cand2. */
7453 /* cand2 is built-in; prefer cand1. */
7458 /* If the two function declarations represent the same function (this can
7459 happen with declarations in multiple scopes and arg-dependent lookup),
7460 arbitrarily choose one. But first make sure the default args we're
7462 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7463 && equal_functions (cand1->fn, cand2->fn))
7465 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7466 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7468 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7470 for (i = 0; i < len; ++i)
7472 /* Don't crash if the fn is variadic. */
7475 parms1 = TREE_CHAIN (parms1);
7476 parms2 = TREE_CHAIN (parms2);
7480 parms1 = TREE_CHAIN (parms1);
7482 parms2 = TREE_CHAIN (parms2);
7486 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7487 TREE_PURPOSE (parms2)))
7491 permerror (input_location, "default argument mismatch in "
7492 "overload resolution");
7493 inform (input_location,
7494 " candidate 1: %q+#F", cand1->fn);
7495 inform (input_location,
7496 " candidate 2: %q+#F", cand2->fn);
7499 add_warning (cand1, cand2);
7502 parms1 = TREE_CHAIN (parms1);
7503 parms2 = TREE_CHAIN (parms2);
7511 /* Extension: If the worst conversion for one candidate is worse than the
7512 worst conversion for the other, take the first. */
7515 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7516 struct z_candidate *w = 0, *l = 0;
7518 for (i = 0; i < len; ++i)
7520 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7521 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7522 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7523 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7526 winner = 1, w = cand1, l = cand2;
7528 winner = -1, w = cand2, l = cand1;
7531 /* Don't choose a deleted function over ambiguity. */
7532 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
7536 pedwarn (input_location, 0,
7537 "ISO C++ says that these are ambiguous, even "
7538 "though the worst conversion for the first is better than "
7539 "the worst conversion for the second:");
7540 print_z_candidate (_("candidate 1:"), w);
7541 print_z_candidate (_("candidate 2:"), l);
7549 gcc_assert (!winner);
7553 /* Given a list of candidates for overloading, find the best one, if any.
7554 This algorithm has a worst case of O(2n) (winner is last), and a best
7555 case of O(n/2) (totally ambiguous); much better than a sorting
7558 static struct z_candidate *
7559 tourney (struct z_candidate *candidates)
7561 struct z_candidate *champ = candidates, *challenger;
7563 int champ_compared_to_predecessor = 0;
7565 /* Walk through the list once, comparing each current champ to the next
7566 candidate, knocking out a candidate or two with each comparison. */
7568 for (challenger = champ->next; challenger; )
7570 fate = joust (champ, challenger, 0);
7572 challenger = challenger->next;
7577 champ = challenger->next;
7580 champ_compared_to_predecessor = 0;
7585 champ_compared_to_predecessor = 1;
7588 challenger = champ->next;
7592 /* Make sure the champ is better than all the candidates it hasn't yet
7593 been compared to. */
7595 for (challenger = candidates;
7597 && !(champ_compared_to_predecessor && challenger->next == champ);
7598 challenger = challenger->next)
7600 fate = joust (champ, challenger, 0);
7608 /* Returns nonzero if things of type FROM can be converted to TO. */
7611 can_convert (tree to, tree from)
7613 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7616 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7619 can_convert_arg (tree to, tree from, tree arg, int flags)
7625 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7626 p = conversion_obstack_alloc (0);
7628 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7630 ok_p = (t && !t->bad_p);
7632 /* Free all the conversions we allocated. */
7633 obstack_free (&conversion_obstack, p);
7638 /* Like can_convert_arg, but allows dubious conversions as well. */
7641 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7646 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7647 p = conversion_obstack_alloc (0);
7648 /* Try to perform the conversion. */
7649 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7651 /* Free all the conversions we allocated. */
7652 obstack_free (&conversion_obstack, p);
7657 /* Convert EXPR to TYPE. Return the converted expression.
7659 Note that we allow bad conversions here because by the time we get to
7660 this point we are committed to doing the conversion. If we end up
7661 doing a bad conversion, convert_like will complain. */
7664 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7669 if (error_operand_p (expr))
7670 return error_mark_node;
7672 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7673 p = conversion_obstack_alloc (0);
7675 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7681 if (complain & tf_error)
7683 /* If expr has unknown type, then it is an overloaded function.
7684 Call instantiate_type to get good error messages. */
7685 if (TREE_TYPE (expr) == unknown_type_node)
7686 instantiate_type (type, expr, complain);
7687 else if (invalid_nonstatic_memfn_p (expr, complain))
7688 /* We gave an error. */;
7690 error ("could not convert %qE to %qT", expr, type);
7692 expr = error_mark_node;
7694 else if (processing_template_decl)
7696 /* In a template, we are only concerned about determining the
7697 type of non-dependent expressions, so we do not have to
7698 perform the actual conversion. */
7699 if (TREE_TYPE (expr) != type)
7700 expr = build_nop (type, expr);
7703 expr = convert_like (conv, expr, complain);
7705 /* Free all the conversions we allocated. */
7706 obstack_free (&conversion_obstack, p);
7712 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7714 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7717 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7718 permitted. If the conversion is valid, the converted expression is
7719 returned. Otherwise, NULL_TREE is returned, except in the case
7720 that TYPE is a class type; in that case, an error is issued. If
7721 C_CAST_P is true, then this direction initialization is taking
7722 place as part of a static_cast being attempted as part of a C-style
7726 perform_direct_initialization_if_possible (tree type,
7729 tsubst_flags_t complain)
7734 if (type == error_mark_node || error_operand_p (expr))
7735 return error_mark_node;
7738 If the destination type is a (possibly cv-qualified) class type:
7740 -- If the initialization is direct-initialization ...,
7741 constructors are considered. ... If no constructor applies, or
7742 the overload resolution is ambiguous, the initialization is
7744 if (CLASS_TYPE_P (type))
7746 VEC(tree,gc) *args = make_tree_vector_single (expr);
7747 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7748 &args, type, LOOKUP_NORMAL, complain);
7749 release_tree_vector (args);
7750 return build_cplus_new (type, expr);
7753 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7754 p = conversion_obstack_alloc (0);
7756 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7759 if (!conv || conv->bad_p)
7762 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7763 /*issue_conversion_warnings=*/false,
7767 /* Free all the conversions we allocated. */
7768 obstack_free (&conversion_obstack, p);
7773 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7774 is being bound to a temporary. Create and return a new VAR_DECL
7775 with the indicated TYPE; this variable will store the value to
7776 which the reference is bound. */
7779 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7783 /* Create the variable. */
7784 var = create_temporary_var (type);
7786 /* Register the variable. */
7787 if (TREE_STATIC (decl))
7789 /* Namespace-scope or local static; give it a mangled name. */
7792 TREE_STATIC (var) = 1;
7793 name = mangle_ref_init_variable (decl);
7794 DECL_NAME (var) = name;
7795 SET_DECL_ASSEMBLER_NAME (var, name);
7796 var = pushdecl_top_level (var);
7799 /* Create a new cleanup level if necessary. */
7800 maybe_push_cleanup_level (type);
7805 /* EXPR is the initializer for a variable DECL of reference or
7806 std::initializer_list type. Create, push and return a new VAR_DECL
7807 for the initializer so that it will live as long as DECL. Any
7808 cleanup for the new variable is returned through CLEANUP, and the
7809 code to initialize the new variable is returned through INITP. */
7812 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7818 /* Create the temporary variable. */
7819 type = TREE_TYPE (expr);
7820 var = make_temporary_var_for_ref_to_temp (decl, type);
7821 layout_decl (var, 0);
7822 /* If the rvalue is the result of a function call it will be
7823 a TARGET_EXPR. If it is some other construct (such as a
7824 member access expression where the underlying object is
7825 itself the result of a function call), turn it into a
7826 TARGET_EXPR here. It is important that EXPR be a
7827 TARGET_EXPR below since otherwise the INIT_EXPR will
7828 attempt to make a bitwise copy of EXPR to initialize
7830 if (TREE_CODE (expr) != TARGET_EXPR)
7831 expr = get_target_expr (expr);
7832 /* Create the INIT_EXPR that will initialize the temporary
7834 init = build2 (INIT_EXPR, type, var, expr);
7835 if (at_function_scope_p ())
7837 add_decl_expr (var);
7839 if (TREE_STATIC (var))
7840 init = add_stmt_to_compound (init, register_dtor_fn (var));
7842 *cleanup = cxx_maybe_build_cleanup (var);
7844 /* We must be careful to destroy the temporary only
7845 after its initialization has taken place. If the
7846 initialization throws an exception, then the
7847 destructor should not be run. We cannot simply
7848 transform INIT into something like:
7850 (INIT, ({ CLEANUP_STMT; }))
7852 because emit_local_var always treats the
7853 initializer as a full-expression. Thus, the
7854 destructor would run too early; it would run at the
7855 end of initializing the reference variable, rather
7856 than at the end of the block enclosing the
7859 The solution is to pass back a cleanup expression
7860 which the caller is responsible for attaching to
7861 the statement tree. */
7865 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7866 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7867 static_aggregates = tree_cons (NULL_TREE, var,
7875 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7876 initializing a variable of that TYPE. If DECL is non-NULL, it is
7877 the VAR_DECL being initialized with the EXPR. (In that case, the
7878 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7879 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7880 return, if *CLEANUP is no longer NULL, it will be an expression
7881 that should be pushed as a cleanup after the returned expression
7882 is used to initialize DECL.
7884 Return the converted expression. */
7887 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
7888 tsubst_flags_t complain)
7893 if (type == error_mark_node || error_operand_p (expr))
7894 return error_mark_node;
7896 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7897 p = conversion_obstack_alloc (0);
7899 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7901 if (!conv || conv->bad_p)
7903 if (complain & tf_error)
7905 if (!CP_TYPE_CONST_P (TREE_TYPE (type))
7906 && !TYPE_REF_IS_RVALUE (type)
7907 && !real_lvalue_p (expr))
7908 error ("invalid initialization of non-const reference of "
7909 "type %qT from an rvalue of type %qT",
7910 type, TREE_TYPE (expr));
7912 error ("invalid initialization of reference of type "
7913 "%qT from expression of type %qT", type,
7916 return error_mark_node;
7919 /* If DECL is non-NULL, then this special rule applies:
7923 The temporary to which the reference is bound or the temporary
7924 that is the complete object to which the reference is bound
7925 persists for the lifetime of the reference.
7927 The temporaries created during the evaluation of the expression
7928 initializing the reference, except the temporary to which the
7929 reference is bound, are destroyed at the end of the
7930 full-expression in which they are created.
7932 In that case, we store the converted expression into a new
7933 VAR_DECL in a new scope.
7935 However, we want to be careful not to create temporaries when
7936 they are not required. For example, given:
7939 struct D : public B {};
7943 there is no need to copy the return value from "f"; we can just
7944 extend its lifetime. Similarly, given:
7947 struct T { operator S(); };
7951 we can extend the lifetime of the return value of the conversion
7953 gcc_assert (conv->kind == ck_ref_bind);
7957 tree base_conv_type;
7959 /* Skip over the REF_BIND. */
7960 conv = conv->u.next;
7961 /* If the next conversion is a BASE_CONV, skip that too -- but
7962 remember that the conversion was required. */
7963 if (conv->kind == ck_base)
7965 base_conv_type = conv->type;
7966 conv = conv->u.next;
7969 base_conv_type = NULL_TREE;
7970 /* Perform the remainder of the conversion. */
7971 expr = convert_like_real (conv, expr,
7972 /*fn=*/NULL_TREE, /*argnum=*/0,
7974 /*issue_conversion_warnings=*/true,
7976 tf_warning_or_error);
7977 if (error_operand_p (expr))
7978 expr = error_mark_node;
7981 if (!lvalue_or_rvalue_with_address_p (expr))
7984 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7985 /* Use its address to initialize the reference variable. */
7986 expr = build_address (var);
7988 expr = convert_to_base (expr,
7989 build_pointer_type (base_conv_type),
7990 /*check_access=*/true,
7991 /*nonnull=*/true, complain);
7992 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7995 /* Take the address of EXPR. */
7996 expr = cp_build_addr_expr (expr, tf_warning_or_error);
7997 /* If a BASE_CONV was required, perform it now. */
7999 expr = (perform_implicit_conversion
8000 (build_pointer_type (base_conv_type), expr,
8001 tf_warning_or_error));
8002 expr = build_nop (type, expr);
8006 /* Perform the conversion. */
8007 expr = convert_like (conv, expr, tf_warning_or_error);
8009 /* Free all the conversions we allocated. */
8010 obstack_free (&conversion_obstack, p);
8015 /* Returns true iff TYPE is some variant of std::initializer_list. */
8018 is_std_init_list (tree type)
8020 /* Look through typedefs. */
8023 type = TYPE_MAIN_VARIANT (type);
8024 return (CLASS_TYPE_P (type)
8025 && CP_TYPE_CONTEXT (type) == std_node
8026 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
8029 /* Returns true iff DECL is a list constructor: i.e. a constructor which
8030 will accept an argument list of a single std::initializer_list<T>. */
8033 is_list_ctor (tree decl)
8035 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
8038 if (!args || args == void_list_node)
8041 arg = non_reference (TREE_VALUE (args));
8042 if (!is_std_init_list (arg))
8045 args = TREE_CHAIN (args);
8047 if (args && args != void_list_node && !TREE_PURPOSE (args))
8048 /* There are more non-defaulted parms. */
8054 #include "gt-cp-call.h"