1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com) and
6 modified by Brendan Kehoe (brendan@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
25 /* High-level class interface. */
29 #include "coretypes.h"
38 #include "diagnostic.h"
42 #include "langhooks.h"
44 /* The various kinds of conversion. */
46 typedef enum conversion_kind {
62 /* The rank of the conversion. Order of the enumerals matters; better
63 conversions should come earlier in the list. */
65 typedef enum conversion_rank {
76 /* An implicit conversion sequence, in the sense of [over.best.ics].
77 The first conversion to be performed is at the end of the chain.
78 That conversion is always a cr_identity conversion. */
80 typedef struct conversion conversion;
82 /* The kind of conversion represented by this step. */
84 /* The rank of this conversion. */
86 BOOL_BITFIELD user_conv_p : 1;
87 BOOL_BITFIELD ellipsis_p : 1;
88 BOOL_BITFIELD this_p : 1;
89 BOOL_BITFIELD bad_p : 1;
90 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
91 temporary should be created to hold the result of the
93 BOOL_BITFIELD need_temporary_p : 1;
94 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
95 from a pointer-to-derived to pointer-to-base is being performed. */
96 BOOL_BITFIELD base_p : 1;
97 /* If KIND is ck_ref_bind, true when either an lvalue reference is
98 being bound to an lvalue expression or an rvalue reference is
99 being bound to an rvalue expression. */
100 BOOL_BITFIELD rvaluedness_matches_p: 1;
101 BOOL_BITFIELD check_narrowing: 1;
102 /* The type of the expression resulting from the conversion. */
105 /* The next conversion in the chain. Since the conversions are
106 arranged from outermost to innermost, the NEXT conversion will
107 actually be performed before this conversion. This variant is
108 used only when KIND is neither ck_identity nor ck_ambig. */
110 /* The expression at the beginning of the conversion chain. This
111 variant is used only if KIND is ck_identity or ck_ambig. */
113 /* The array of conversions for an initializer_list. */
116 /* The function candidate corresponding to this conversion
117 sequence. This field is only used if KIND is ck_user. */
118 struct z_candidate *cand;
121 #define CONVERSION_RANK(NODE) \
122 ((NODE)->bad_p ? cr_bad \
123 : (NODE)->ellipsis_p ? cr_ellipsis \
124 : (NODE)->user_conv_p ? cr_user \
127 static struct obstack conversion_obstack;
128 static bool conversion_obstack_initialized;
130 static struct z_candidate * tourney (struct z_candidate *);
131 static int equal_functions (tree, tree);
132 static int joust (struct z_candidate *, struct z_candidate *, bool);
133 static int compare_ics (conversion *, conversion *);
134 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
135 static tree build_java_interface_fn_ref (tree, tree);
136 #define convert_like(CONV, EXPR, COMPLAIN) \
137 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
138 /*issue_conversion_warnings=*/true, \
139 /*c_cast_p=*/false, (COMPLAIN))
140 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
141 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
142 /*issue_conversion_warnings=*/true, \
143 /*c_cast_p=*/false, (COMPLAIN))
144 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
145 bool, tsubst_flags_t);
146 static void op_error (enum tree_code, enum tree_code, tree, tree,
148 static VEC(tree,gc) *resolve_args (VEC(tree,gc) *);
149 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
150 static void print_z_candidate (const char *, struct z_candidate *);
151 static void print_z_candidates (struct z_candidate *);
152 static tree build_this (tree);
153 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
154 static bool any_strictly_viable (struct z_candidate *);
155 static struct z_candidate *add_template_candidate
156 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
157 tree, tree, tree, int, unification_kind_t);
158 static struct z_candidate *add_template_candidate_real
159 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
160 tree, tree, tree, int, tree, unification_kind_t);
161 static struct z_candidate *add_template_conv_candidate
162 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
164 static void add_builtin_candidates
165 (struct z_candidate **, enum tree_code, enum tree_code,
167 static void add_builtin_candidate
168 (struct z_candidate **, enum tree_code, enum tree_code,
169 tree, tree, tree, tree *, tree *, int);
170 static bool is_complete (tree);
171 static void build_builtin_candidate
172 (struct z_candidate **, tree, tree, tree, tree *, tree *,
174 static struct z_candidate *add_conv_candidate
175 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
177 static struct z_candidate *add_function_candidate
178 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
180 static conversion *implicit_conversion (tree, tree, tree, bool, int);
181 static conversion *standard_conversion (tree, tree, tree, bool, int);
182 static conversion *reference_binding (tree, tree, tree, bool, int);
183 static conversion *build_conv (conversion_kind, tree, conversion *);
184 static conversion *build_list_conv (tree, tree, int);
185 static bool is_subseq (conversion *, conversion *);
186 static conversion *maybe_handle_ref_bind (conversion **);
187 static void maybe_handle_implicit_object (conversion **);
188 static struct z_candidate *add_candidate
189 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
190 conversion **, tree, tree, int);
191 static tree source_type (conversion *);
192 static void add_warning (struct z_candidate *, struct z_candidate *);
193 static bool reference_compatible_p (tree, tree);
194 static conversion *convert_class_to_reference (tree, tree, tree, int);
195 static conversion *direct_reference_binding (tree, conversion *);
196 static bool promoted_arithmetic_type_p (tree);
197 static conversion *conditional_conversion (tree, tree);
198 static char *name_as_c_string (tree, tree, bool *);
199 static tree prep_operand (tree);
200 static void add_candidates (tree, const VEC(tree,gc) *, tree, bool, tree, tree,
201 int, struct z_candidate **);
202 static conversion *merge_conversion_sequences (conversion *, conversion *);
203 static bool magic_varargs_p (tree);
204 static tree build_temp (tree, tree, int, diagnostic_t *);
206 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
207 NAME can take many forms... */
210 check_dtor_name (tree basetype, tree name)
212 /* Just accept something we've already complained about. */
213 if (name == error_mark_node)
216 if (TREE_CODE (name) == TYPE_DECL)
217 name = TREE_TYPE (name);
218 else if (TYPE_P (name))
220 else if (TREE_CODE (name) == IDENTIFIER_NODE)
222 if ((MAYBE_CLASS_TYPE_P (basetype)
223 && name == constructor_name (basetype))
224 || (TREE_CODE (basetype) == ENUMERAL_TYPE
225 && name == TYPE_IDENTIFIER (basetype)))
228 name = get_type_value (name);
234 template <class T> struct S { ~S(); };
238 NAME will be a class template. */
239 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
243 if (!name || name == error_mark_node)
245 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
248 /* We want the address of a function or method. We avoid creating a
249 pointer-to-member function. */
252 build_addr_func (tree function)
254 tree type = TREE_TYPE (function);
256 /* We have to do these by hand to avoid real pointer to member
258 if (TREE_CODE (type) == METHOD_TYPE)
260 if (TREE_CODE (function) == OFFSET_REF)
262 tree object = build_address (TREE_OPERAND (function, 0));
263 return get_member_function_from_ptrfunc (&object,
264 TREE_OPERAND (function, 1));
266 function = build_address (function);
269 function = decay_conversion (function);
274 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
275 POINTER_TYPE to those. Note, pointer to member function types
276 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
277 two variants. build_call_a is the primitive taking an array of
278 arguments, while build_call_n is a wrapper that handles varargs. */
281 build_call_n (tree function, int n, ...)
284 return build_call_a (function, 0, NULL);
287 tree *argarray = (tree *) alloca (n * sizeof (tree));
292 for (i = 0; i < n; i++)
293 argarray[i] = va_arg (ap, tree);
295 return build_call_a (function, n, argarray);
300 build_call_a (tree function, int n, tree *argarray)
302 int is_constructor = 0;
309 function = build_addr_func (function);
311 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
312 fntype = TREE_TYPE (TREE_TYPE (function));
313 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
314 || TREE_CODE (fntype) == METHOD_TYPE);
315 result_type = TREE_TYPE (fntype);
317 if (TREE_CODE (function) == ADDR_EXPR
318 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
320 decl = TREE_OPERAND (function, 0);
321 if (!TREE_USED (decl))
323 /* We invoke build_call directly for several library
324 functions. These may have been declared normally if
325 we're building libgcc, so we can't just check
327 gcc_assert (DECL_ARTIFICIAL (decl)
328 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
336 /* We check both the decl and the type; a function may be known not to
337 throw without being declared throw(). */
338 nothrow = ((decl && TREE_NOTHROW (decl))
339 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
341 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
342 current_function_returns_abnormally = 1;
344 if (decl && TREE_DEPRECATED (decl))
345 warn_deprecated_use (decl, NULL_TREE);
346 require_complete_eh_spec_types (fntype, decl);
348 if (decl && DECL_CONSTRUCTOR_P (decl))
351 /* Don't pass empty class objects by value. This is useful
352 for tags in STL, which are used to control overload resolution.
353 We don't need to handle other cases of copying empty classes. */
354 if (! decl || ! DECL_BUILT_IN (decl))
355 for (i = 0; i < n; i++)
356 if (is_empty_class (TREE_TYPE (argarray[i]))
357 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
359 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
360 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
364 function = build_call_array_loc (input_location,
365 result_type, function, n, argarray);
366 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
367 TREE_NOTHROW (function) = nothrow;
372 /* Build something of the form ptr->method (args)
373 or object.method (args). This can also build
374 calls to constructors, and find friends.
376 Member functions always take their class variable
379 INSTANCE is a class instance.
381 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
383 PARMS help to figure out what that NAME really refers to.
385 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
386 down to the real instance type to use for access checking. We need this
387 information to get protected accesses correct.
389 FLAGS is the logical disjunction of zero or more LOOKUP_
390 flags. See cp-tree.h for more info.
392 If this is all OK, calls build_function_call with the resolved
395 This function must also handle being called to perform
396 initialization, promotion/coercion of arguments, and
397 instantiation of default parameters.
399 Note that NAME may refer to an instance variable name. If
400 `operator()()' is defined for the type of that field, then we return
403 /* New overloading code. */
405 typedef struct z_candidate z_candidate;
407 typedef struct candidate_warning candidate_warning;
408 struct candidate_warning {
410 candidate_warning *next;
414 /* The FUNCTION_DECL that will be called if this candidate is
415 selected by overload resolution. */
417 /* If not NULL_TREE, the first argument to use when calling this
420 /* The rest of the arguments to use when calling this function. If
421 there are no further arguments this may be NULL or it may be an
423 const VEC(tree,gc) *args;
424 /* The implicit conversion sequences for each of the arguments to
427 /* The number of implicit conversion sequences. */
429 /* If FN is a user-defined conversion, the standard conversion
430 sequence from the type returned by FN to the desired destination
432 conversion *second_conv;
434 /* If FN is a member function, the binfo indicating the path used to
435 qualify the name of FN at the call site. This path is used to
436 determine whether or not FN is accessible if it is selected by
437 overload resolution. The DECL_CONTEXT of FN will always be a
438 (possibly improper) base of this binfo. */
440 /* If FN is a non-static member function, the binfo indicating the
441 subobject to which the `this' pointer should be converted if FN
442 is selected by overload resolution. The type pointed to the by
443 the `this' pointer must correspond to the most derived class
444 indicated by the CONVERSION_PATH. */
445 tree conversion_path;
447 candidate_warning *warnings;
451 /* Returns true iff T is a null pointer constant in the sense of
455 null_ptr_cst_p (tree t)
459 A null pointer constant is an integral constant expression
460 (_expr.const_) rvalue of integer type that evaluates to zero. */
461 t = integral_constant_value (t);
464 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
467 if (!TREE_OVERFLOW (t))
473 /* Returns nonzero if PARMLIST consists of only default parms and/or
477 sufficient_parms_p (const_tree parmlist)
479 for (; parmlist && parmlist != void_list_node;
480 parmlist = TREE_CHAIN (parmlist))
481 if (!TREE_PURPOSE (parmlist))
486 /* Allocate N bytes of memory from the conversion obstack. The memory
487 is zeroed before being returned. */
490 conversion_obstack_alloc (size_t n)
493 if (!conversion_obstack_initialized)
495 gcc_obstack_init (&conversion_obstack);
496 conversion_obstack_initialized = true;
498 p = obstack_alloc (&conversion_obstack, n);
503 /* Dynamically allocate a conversion. */
506 alloc_conversion (conversion_kind kind)
509 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
514 #ifdef ENABLE_CHECKING
516 /* Make sure that all memory on the conversion obstack has been
520 validate_conversion_obstack (void)
522 if (conversion_obstack_initialized)
523 gcc_assert ((obstack_next_free (&conversion_obstack)
524 == obstack_base (&conversion_obstack)));
527 #endif /* ENABLE_CHECKING */
529 /* Dynamically allocate an array of N conversions. */
532 alloc_conversions (size_t n)
534 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
538 build_conv (conversion_kind code, tree type, conversion *from)
541 conversion_rank rank = CONVERSION_RANK (from);
543 /* Note that the caller is responsible for filling in t->cand for
544 user-defined conversions. */
545 t = alloc_conversion (code);
568 t->user_conv_p = (code == ck_user || from->user_conv_p);
569 t->bad_p = from->bad_p;
574 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
575 specialization of std::initializer_list<T>, if such a conversion is
579 build_list_conv (tree type, tree ctor, int flags)
581 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
582 unsigned len = CONSTRUCTOR_NELTS (ctor);
583 conversion **subconvs = alloc_conversions (len);
588 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
591 = implicit_conversion (elttype, TREE_TYPE (val), val,
599 t = alloc_conversion (ck_list);
601 t->u.list = subconvs;
604 for (i = 0; i < len; ++i)
606 conversion *sub = subconvs[i];
607 if (sub->rank > t->rank)
609 if (sub->user_conv_p)
610 t->user_conv_p = true;
618 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
619 aggregate class, if such a conversion is possible. */
622 build_aggr_conv (tree type, tree ctor, int flags)
624 unsigned HOST_WIDE_INT i = 0;
626 tree field = TYPE_FIELDS (type);
628 for (; field; field = TREE_CHAIN (field), ++i)
630 if (TREE_CODE (field) != FIELD_DECL)
632 if (i < CONSTRUCTOR_NELTS (ctor))
634 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
635 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
639 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
643 c = alloc_conversion (ck_aggr);
646 c->user_conv_p = true;
651 /* Build a representation of the identity conversion from EXPR to
652 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
655 build_identity_conv (tree type, tree expr)
659 c = alloc_conversion (ck_identity);
666 /* Converting from EXPR to TYPE was ambiguous in the sense that there
667 were multiple user-defined conversions to accomplish the job.
668 Build a conversion that indicates that ambiguity. */
671 build_ambiguous_conv (tree type, tree expr)
675 c = alloc_conversion (ck_ambig);
683 strip_top_quals (tree t)
685 if (TREE_CODE (t) == ARRAY_TYPE)
687 return cp_build_qualified_type (t, 0);
690 /* Returns the standard conversion path (see [conv]) from type FROM to type
691 TO, if any. For proper handling of null pointer constants, you must
692 also pass the expression EXPR to convert from. If C_CAST_P is true,
693 this conversion is coming from a C-style cast. */
696 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
699 enum tree_code fcode, tcode;
701 bool fromref = false;
703 to = non_reference (to);
704 if (TREE_CODE (from) == REFERENCE_TYPE)
707 from = TREE_TYPE (from);
709 to = strip_top_quals (to);
710 from = strip_top_quals (from);
712 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
713 && expr && type_unknown_p (expr))
715 tsubst_flags_t tflags = tf_conv;
716 if (!(flags & LOOKUP_PROTECT))
717 tflags |= tf_no_access_control;
718 expr = instantiate_type (to, expr, tflags);
719 if (expr == error_mark_node)
721 from = TREE_TYPE (expr);
724 fcode = TREE_CODE (from);
725 tcode = TREE_CODE (to);
727 conv = build_identity_conv (from, expr);
728 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
730 from = type_decays_to (from);
731 fcode = TREE_CODE (from);
732 conv = build_conv (ck_lvalue, from, conv);
734 else if (fromref || (expr && lvalue_p (expr)))
739 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
742 from = strip_top_quals (bitfield_type);
743 fcode = TREE_CODE (from);
746 conv = build_conv (ck_rvalue, from, conv);
749 /* Allow conversion between `__complex__' data types. */
750 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
752 /* The standard conversion sequence to convert FROM to TO is
753 the standard conversion sequence to perform componentwise
755 conversion *part_conv = standard_conversion
756 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
760 conv = build_conv (part_conv->kind, to, conv);
761 conv->rank = part_conv->rank;
769 if (same_type_p (from, to))
772 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
773 && expr && null_ptr_cst_p (expr))
774 conv = build_conv (ck_std, to, conv);
775 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
776 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
778 /* For backwards brain damage compatibility, allow interconversion of
779 pointers and integers with a pedwarn. */
780 conv = build_conv (ck_std, to, conv);
783 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
785 /* For backwards brain damage compatibility, allow interconversion of
786 enums and integers with a pedwarn. */
787 conv = build_conv (ck_std, to, conv);
790 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
791 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
796 if (tcode == POINTER_TYPE
797 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
800 else if (VOID_TYPE_P (TREE_TYPE (to))
801 && !TYPE_PTRMEM_P (from)
802 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
804 from = build_pointer_type
805 (cp_build_qualified_type (void_type_node,
806 cp_type_quals (TREE_TYPE (from))));
807 conv = build_conv (ck_ptr, from, conv);
809 else if (TYPE_PTRMEM_P (from))
811 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
812 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
814 if (DERIVED_FROM_P (fbase, tbase)
815 && (same_type_ignoring_top_level_qualifiers_p
816 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
817 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
819 from = build_ptrmem_type (tbase,
820 TYPE_PTRMEM_POINTED_TO_TYPE (from));
821 conv = build_conv (ck_pmem, from, conv);
823 else if (!same_type_p (fbase, tbase))
826 else if (CLASS_TYPE_P (TREE_TYPE (from))
827 && CLASS_TYPE_P (TREE_TYPE (to))
830 An rvalue of type "pointer to cv D," where D is a
831 class type, can be converted to an rvalue of type
832 "pointer to cv B," where B is a base class (clause
833 _class.derived_) of D. If B is an inaccessible
834 (clause _class.access_) or ambiguous
835 (_class.member.lookup_) base class of D, a program
836 that necessitates this conversion is ill-formed.
837 Therefore, we use DERIVED_FROM_P, and do not check
838 access or uniqueness. */
839 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
842 cp_build_qualified_type (TREE_TYPE (to),
843 cp_type_quals (TREE_TYPE (from)));
844 from = build_pointer_type (from);
845 conv = build_conv (ck_ptr, from, conv);
849 if (tcode == POINTER_TYPE)
851 to_pointee = TREE_TYPE (to);
852 from_pointee = TREE_TYPE (from);
856 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
857 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
860 if (same_type_p (from, to))
862 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
863 /* In a C-style cast, we ignore CV-qualification because we
864 are allowed to perform a static_cast followed by a
866 conv = build_conv (ck_qual, to, conv);
867 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
868 conv = build_conv (ck_qual, to, conv);
869 else if (expr && string_conv_p (to, expr, 0))
870 /* converting from string constant to char *. */
871 conv = build_conv (ck_qual, to, conv);
872 else if (ptr_reasonably_similar (to_pointee, from_pointee))
874 conv = build_conv (ck_ptr, to, conv);
882 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
884 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
885 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
886 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
887 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
889 if (!DERIVED_FROM_P (fbase, tbase)
890 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
891 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
892 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
893 || cp_type_quals (fbase) != cp_type_quals (tbase))
896 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
897 from = build_method_type_directly (from,
899 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
900 from = build_ptrmemfunc_type (build_pointer_type (from));
901 conv = build_conv (ck_pmem, from, conv);
904 else if (tcode == BOOLEAN_TYPE)
908 An rvalue of arithmetic, unscoped enumeration, pointer, or
909 pointer to member type can be converted to an rvalue of type
911 if (ARITHMETIC_TYPE_P (from)
912 || UNSCOPED_ENUM_P (from)
913 || fcode == POINTER_TYPE
914 || TYPE_PTR_TO_MEMBER_P (from))
916 conv = build_conv (ck_std, to, conv);
917 if (fcode == POINTER_TYPE
918 || TYPE_PTRMEM_P (from)
919 || (TYPE_PTRMEMFUNC_P (from)
920 && conv->rank < cr_pbool))
921 conv->rank = cr_pbool;
927 /* We don't check for ENUMERAL_TYPE here because there are no standard
928 conversions to enum type. */
929 /* As an extension, allow conversion to complex type. */
930 else if (ARITHMETIC_TYPE_P (to))
932 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
933 || SCOPED_ENUM_P (from))
935 conv = build_conv (ck_std, to, conv);
937 /* Give this a better rank if it's a promotion. */
938 if (same_type_p (to, type_promotes_to (from))
939 && conv->u.next->rank <= cr_promotion)
940 conv->rank = cr_promotion;
942 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
943 && vector_types_convertible_p (from, to, false))
944 return build_conv (ck_std, to, conv);
945 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
946 && is_properly_derived_from (from, to))
948 if (conv->kind == ck_rvalue)
950 conv = build_conv (ck_base, to, conv);
951 /* The derived-to-base conversion indicates the initialization
952 of a parameter with base type from an object of a derived
953 type. A temporary object is created to hold the result of
954 the conversion unless we're binding directly to a reference. */
955 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
960 if (flags & LOOKUP_NO_NARROWING)
961 conv->check_narrowing = true;
966 /* Returns nonzero if T1 is reference-related to T2. */
969 reference_related_p (tree t1, tree t2)
971 t1 = TYPE_MAIN_VARIANT (t1);
972 t2 = TYPE_MAIN_VARIANT (t2);
976 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
977 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
979 return (same_type_p (t1, t2)
980 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
981 && DERIVED_FROM_P (t1, t2)));
984 /* Returns nonzero if T1 is reference-compatible with T2. */
987 reference_compatible_p (tree t1, tree t2)
991 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
992 reference-related to T2 and cv1 is the same cv-qualification as,
993 or greater cv-qualification than, cv2. */
994 return (reference_related_p (t1, t2)
995 && at_least_as_qualified_p (t1, t2));
998 /* Determine whether or not the EXPR (of class type S) can be
999 converted to T as in [over.match.ref]. */
1002 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1008 struct z_candidate *candidates;
1009 struct z_candidate *cand;
1012 conversions = lookup_conversions (s);
1018 Assuming that "cv1 T" is the underlying type of the reference
1019 being initialized, and "cv S" is the type of the initializer
1020 expression, with S a class type, the candidate functions are
1021 selected as follows:
1023 --The conversion functions of S and its base classes are
1024 considered. Those that are not hidden within S and yield type
1025 "reference to cv2 T2", where "cv1 T" is reference-compatible
1026 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1028 The argument list has one argument, which is the initializer
1033 /* Conceptually, we should take the address of EXPR and put it in
1034 the argument list. Unfortunately, however, that can result in
1035 error messages, which we should not issue now because we are just
1036 trying to find a conversion operator. Therefore, we use NULL,
1037 cast to the appropriate type. */
1038 first_arg = build_int_cst (build_pointer_type (s), 0);
1040 t = TREE_TYPE (reference_type);
1042 for (; conversions; conversions = TREE_CHAIN (conversions))
1044 tree fns = TREE_VALUE (conversions);
1046 for (; fns; fns = OVL_NEXT (fns))
1048 tree f = OVL_CURRENT (fns);
1049 tree t2 = TREE_TYPE (TREE_TYPE (f));
1051 if (DECL_NONCONVERTING_P (f)
1052 && (flags & LOOKUP_ONLYCONVERTING))
1057 /* If this is a template function, try to get an exact
1059 if (TREE_CODE (f) == TEMPLATE_DECL)
1061 cand = add_template_candidate (&candidates,
1068 TREE_PURPOSE (conversions),
1074 /* Now, see if the conversion function really returns
1075 an lvalue of the appropriate type. From the
1076 point of view of unification, simply returning an
1077 rvalue of the right type is good enough. */
1079 t2 = TREE_TYPE (TREE_TYPE (f));
1080 if (TREE_CODE (t2) != REFERENCE_TYPE
1081 || !reference_compatible_p (t, TREE_TYPE (t2)))
1083 candidates = candidates->next;
1088 else if (TREE_CODE (t2) == REFERENCE_TYPE
1089 && reference_compatible_p (t, TREE_TYPE (t2)))
1090 cand = add_function_candidate (&candidates, f, s, first_arg,
1091 NULL, TYPE_BINFO (s),
1092 TREE_PURPOSE (conversions),
1097 conversion *identity_conv;
1098 /* Build a standard conversion sequence indicating the
1099 binding from the reference type returned by the
1100 function to the desired REFERENCE_TYPE. */
1102 = build_identity_conv (TREE_TYPE (TREE_TYPE
1103 (TREE_TYPE (cand->fn))),
1106 = (direct_reference_binding
1107 (reference_type, identity_conv));
1108 cand->second_conv->rvaluedness_matches_p
1109 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1110 == TYPE_REF_IS_RVALUE (reference_type);
1111 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1113 /* Don't allow binding of lvalues to rvalue references. */
1114 if (TYPE_REF_IS_RVALUE (reference_type)
1115 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1116 cand->second_conv->bad_p = true;
1121 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1122 /* If none of the conversion functions worked out, let our caller
1127 cand = tourney (candidates);
1131 /* Now that we know that this is the function we're going to use fix
1132 the dummy first argument. */
1133 gcc_assert (cand->first_arg == NULL_TREE
1134 || integer_zerop (cand->first_arg));
1135 cand->first_arg = build_this (expr);
1137 /* Build a user-defined conversion sequence representing the
1139 conv = build_conv (ck_user,
1140 TREE_TYPE (TREE_TYPE (cand->fn)),
1141 build_identity_conv (TREE_TYPE (expr), expr));
1144 if (cand->viable == -1)
1147 /* Merge it with the standard conversion sequence from the
1148 conversion function's return type to the desired type. */
1149 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1151 return cand->second_conv;
1154 /* A reference of the indicated TYPE is being bound directly to the
1155 expression represented by the implicit conversion sequence CONV.
1156 Return a conversion sequence for this binding. */
1159 direct_reference_binding (tree type, conversion *conv)
1163 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1164 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1166 t = TREE_TYPE (type);
1170 When a parameter of reference type binds directly
1171 (_dcl.init.ref_) to an argument expression, the implicit
1172 conversion sequence is the identity conversion, unless the
1173 argument expression has a type that is a derived class of the
1174 parameter type, in which case the implicit conversion sequence is
1175 a derived-to-base Conversion.
1177 If the parameter binds directly to the result of applying a
1178 conversion function to the argument expression, the implicit
1179 conversion sequence is a user-defined conversion sequence
1180 (_over.ics.user_), with the second standard conversion sequence
1181 either an identity conversion or, if the conversion function
1182 returns an entity of a type that is a derived class of the
1183 parameter type, a derived-to-base conversion. */
1184 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1186 /* Represent the derived-to-base conversion. */
1187 conv = build_conv (ck_base, t, conv);
1188 /* We will actually be binding to the base-class subobject in
1189 the derived class, so we mark this conversion appropriately.
1190 That way, convert_like knows not to generate a temporary. */
1191 conv->need_temporary_p = false;
1193 return build_conv (ck_ref_bind, type, conv);
1196 /* Returns the conversion path from type FROM to reference type TO for
1197 purposes of reference binding. For lvalue binding, either pass a
1198 reference type to FROM or an lvalue expression to EXPR. If the
1199 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1200 the conversion returned. If C_CAST_P is true, this
1201 conversion is coming from a C-style cast. */
1204 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1206 conversion *conv = NULL;
1207 tree to = TREE_TYPE (rto);
1212 cp_lvalue_kind is_lvalue = clk_none;
1214 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1216 expr = instantiate_type (to, expr, tf_none);
1217 if (expr == error_mark_node)
1219 from = TREE_TYPE (expr);
1222 if (TREE_CODE (from) == REFERENCE_TYPE)
1224 /* Anything with reference type is an lvalue. */
1225 is_lvalue = clk_ordinary;
1226 from = TREE_TYPE (from);
1229 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1231 maybe_warn_cpp0x ("extended initializer lists");
1232 conv = implicit_conversion (to, from, expr, c_cast_p,
1234 if (!CLASS_TYPE_P (to)
1235 && CONSTRUCTOR_NELTS (expr) == 1)
1237 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1238 from = TREE_TYPE (expr);
1242 if (is_lvalue == clk_none && expr)
1243 is_lvalue = real_lvalue_p (expr);
1246 if ((is_lvalue & clk_bitfield) != 0)
1247 tfrom = unlowered_expr_type (expr);
1249 /* Figure out whether or not the types are reference-related and
1250 reference compatible. We have do do this after stripping
1251 references from FROM. */
1252 related_p = reference_related_p (to, tfrom);
1253 /* If this is a C cast, first convert to an appropriately qualified
1254 type, so that we can later do a const_cast to the desired type. */
1255 if (related_p && c_cast_p
1256 && !at_least_as_qualified_p (to, tfrom))
1257 to = build_qualified_type (to, cp_type_quals (tfrom));
1258 compatible_p = reference_compatible_p (to, tfrom);
1260 /* Directly bind reference when target expression's type is compatible with
1261 the reference and expression is an lvalue. In DR391, the wording in
1262 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1263 const and rvalue references to rvalues of compatible class type.
1264 We should also do direct bindings for non-class "rvalues" derived from
1265 rvalue references. */
1268 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1269 && !(flags & LOOKUP_NO_TEMP_BIND))
1270 || TYPE_REF_IS_RVALUE (rto))
1271 && (CLASS_TYPE_P (from) || (expr && lvalue_p (expr))))))
1275 If the initializer expression
1277 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1278 is reference-compatible with "cv2 T2,"
1280 the reference is bound directly to the initializer expression
1284 If the initializer expression is an rvalue, with T2 a class type,
1285 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1286 is bound to the object represented by the rvalue or to a sub-object
1287 within that object. */
1289 conv = build_identity_conv (tfrom, expr);
1290 conv = direct_reference_binding (rto, conv);
1292 if (flags & LOOKUP_PREFER_RVALUE)
1293 /* The top-level caller requested that we pretend that the lvalue
1294 be treated as an rvalue. */
1295 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1297 conv->rvaluedness_matches_p
1298 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1300 if ((is_lvalue & clk_bitfield) != 0
1301 || ((is_lvalue & clk_packed) != 0 && !TYPE_PACKED (to)))
1302 /* For the purposes of overload resolution, we ignore the fact
1303 this expression is a bitfield or packed field. (In particular,
1304 [over.ics.ref] says specifically that a function with a
1305 non-const reference parameter is viable even if the
1306 argument is a bitfield.)
1308 However, when we actually call the function we must create
1309 a temporary to which to bind the reference. If the
1310 reference is volatile, or isn't const, then we cannot make
1311 a temporary, so we just issue an error when the conversion
1313 conv->need_temporary_p = true;
1315 /* Don't allow binding of lvalues to rvalue references. */
1316 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1317 && !(flags & LOOKUP_PREFER_RVALUE))
1322 /* [class.conv.fct] A conversion function is never used to convert a
1323 (possibly cv-qualified) object to the (possibly cv-qualified) same
1324 object type (or a reference to it), to a (possibly cv-qualified) base
1325 class of that type (or a reference to it).... */
1326 else if (CLASS_TYPE_P (from) && !related_p
1327 && !(flags & LOOKUP_NO_CONVERSION))
1331 If the initializer expression
1333 -- has a class type (i.e., T2 is a class type) can be
1334 implicitly converted to an lvalue of type "cv3 T3," where
1335 "cv1 T1" is reference-compatible with "cv3 T3". (this
1336 conversion is selected by enumerating the applicable
1337 conversion functions (_over.match.ref_) and choosing the
1338 best one through overload resolution. (_over.match_).
1340 the reference is bound to the lvalue result of the conversion
1341 in the second case. */
1342 conv = convert_class_to_reference (rto, from, expr, flags);
1347 /* From this point on, we conceptually need temporaries, even if we
1348 elide them. Only the cases above are "direct bindings". */
1349 if (flags & LOOKUP_NO_TEMP_BIND)
1354 When a parameter of reference type is not bound directly to an
1355 argument expression, the conversion sequence is the one required
1356 to convert the argument expression to the underlying type of the
1357 reference according to _over.best.ics_. Conceptually, this
1358 conversion sequence corresponds to copy-initializing a temporary
1359 of the underlying type with the argument expression. Any
1360 difference in top-level cv-qualification is subsumed by the
1361 initialization itself and does not constitute a conversion. */
1365 Otherwise, the reference shall be to a non-volatile const type.
1367 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1368 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1373 Otherwise, a temporary of type "cv1 T1" is created and
1374 initialized from the initializer expression using the rules for a
1375 non-reference copy initialization. If T1 is reference-related to
1376 T2, cv1 must be the same cv-qualification as, or greater
1377 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1378 if (related_p && !at_least_as_qualified_p (to, from))
1381 /* We're generating a temporary now, but don't bind any more in the
1382 conversion (specifically, don't slice the temporary returned by a
1383 conversion operator). */
1384 flags |= LOOKUP_NO_TEMP_BIND;
1386 /* Temporaries are copy-initialized, except for this hack to allow
1387 explicit conversion ops to the copy ctor. See also
1388 add_function_candidate. */
1389 if (!(flags & LOOKUP_COPY_PARM))
1390 flags |= LOOKUP_ONLYCONVERTING;
1393 conv = implicit_conversion (to, from, expr, c_cast_p,
1398 conv = build_conv (ck_ref_bind, rto, conv);
1399 /* This reference binding, unlike those above, requires the
1400 creation of a temporary. */
1401 conv->need_temporary_p = true;
1402 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1407 /* Returns the implicit conversion sequence (see [over.ics]) from type
1408 FROM to type TO. The optional expression EXPR may affect the
1409 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1410 true, this conversion is coming from a C-style cast. */
1413 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1418 if (from == error_mark_node || to == error_mark_node
1419 || expr == error_mark_node)
1422 if (TREE_CODE (to) == REFERENCE_TYPE)
1423 conv = reference_binding (to, from, expr, c_cast_p, flags);
1425 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1430 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1432 if (is_std_init_list (to))
1433 return build_list_conv (to, expr, flags);
1435 /* Allow conversion from an initializer-list with one element to a
1437 if (SCALAR_TYPE_P (to))
1439 int nelts = CONSTRUCTOR_NELTS (expr);
1443 elt = integer_zero_node;
1444 else if (nelts == 1)
1445 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1447 elt = error_mark_node;
1449 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1453 conv->check_narrowing = true;
1454 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1455 /* Too many levels of braces, i.e. '{{1}}'. */
1462 if (expr != NULL_TREE
1463 && (MAYBE_CLASS_TYPE_P (from)
1464 || MAYBE_CLASS_TYPE_P (to))
1465 && (flags & LOOKUP_NO_CONVERSION) == 0)
1467 struct z_candidate *cand;
1468 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING));
1470 if (CLASS_TYPE_P (to)
1471 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1472 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1473 return build_aggr_conv (to, expr, flags);
1475 cand = build_user_type_conversion_1 (to, expr, convflags);
1477 conv = cand->second_conv;
1479 /* We used to try to bind a reference to a temporary here, but that
1480 is now handled after the recursive call to this function at the end
1481 of reference_binding. */
1488 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1489 functions. ARGS will not be changed until a single candidate is
1492 static struct z_candidate *
1493 add_candidate (struct z_candidate **candidates,
1494 tree fn, tree first_arg, const VEC(tree,gc) *args,
1495 size_t num_convs, conversion **convs,
1496 tree access_path, tree conversion_path,
1499 struct z_candidate *cand = (struct z_candidate *)
1500 conversion_obstack_alloc (sizeof (struct z_candidate));
1503 cand->first_arg = first_arg;
1505 cand->convs = convs;
1506 cand->num_convs = num_convs;
1507 cand->access_path = access_path;
1508 cand->conversion_path = conversion_path;
1509 cand->viable = viable;
1510 cand->next = *candidates;
1516 /* Create an overload candidate for the function or method FN called
1517 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1518 FLAGS is passed on to implicit_conversion.
1520 This does not change ARGS.
1522 CTYPE, if non-NULL, is the type we want to pretend this function
1523 comes from for purposes of overload resolution. */
1525 static struct z_candidate *
1526 add_function_candidate (struct z_candidate **candidates,
1527 tree fn, tree ctype, tree first_arg,
1528 const VEC(tree,gc) *args, tree access_path,
1529 tree conversion_path, int flags)
1531 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1535 tree orig_first_arg = first_arg;
1539 /* At this point we should not see any functions which haven't been
1540 explicitly declared, except for friend functions which will have
1541 been found using argument dependent lookup. */
1542 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1544 /* The `this', `in_chrg' and VTT arguments to constructors are not
1545 considered in overload resolution. */
1546 if (DECL_CONSTRUCTOR_P (fn))
1548 parmlist = skip_artificial_parms_for (fn, parmlist);
1549 skip = num_artificial_parms_for (fn);
1550 if (skip > 0 && first_arg != NULL_TREE)
1553 first_arg = NULL_TREE;
1559 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1560 convs = alloc_conversions (len);
1562 /* 13.3.2 - Viable functions [over.match.viable]
1563 First, to be a viable function, a candidate function shall have enough
1564 parameters to agree in number with the arguments in the list.
1566 We need to check this first; otherwise, checking the ICSes might cause
1567 us to produce an ill-formed template instantiation. */
1569 parmnode = parmlist;
1570 for (i = 0; i < len; ++i)
1572 if (parmnode == NULL_TREE || parmnode == void_list_node)
1574 parmnode = TREE_CHAIN (parmnode);
1577 if (i < len && parmnode)
1580 /* Make sure there are default args for the rest of the parms. */
1581 else if (!sufficient_parms_p (parmnode))
1587 /* Second, for F to be a viable function, there shall exist for each
1588 argument an implicit conversion sequence that converts that argument
1589 to the corresponding parameter of F. */
1591 parmnode = parmlist;
1593 for (i = 0; i < len; ++i)
1599 if (parmnode == void_list_node)
1602 if (i == 0 && first_arg != NULL_TREE)
1605 arg = VEC_index (tree, args,
1606 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1607 argtype = lvalue_type (arg);
1609 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1610 && ! DECL_CONSTRUCTOR_P (fn));
1614 tree parmtype = TREE_VALUE (parmnode);
1617 /* The type of the implicit object parameter ('this') for
1618 overload resolution is not always the same as for the
1619 function itself; conversion functions are considered to
1620 be members of the class being converted, and functions
1621 introduced by a using-declaration are considered to be
1622 members of the class that uses them.
1624 Since build_over_call ignores the ICS for the `this'
1625 parameter, we can just change the parm type. */
1626 if (ctype && is_this)
1629 = build_qualified_type (ctype,
1630 TYPE_QUALS (TREE_TYPE (parmtype)));
1631 parmtype = build_pointer_type (parmtype);
1634 if (ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1636 /* Hack: Direct-initialize copy parm (i.e. suppress
1637 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1638 work. See also reference_binding. */
1639 lflags |= LOOKUP_COPY_PARM;
1640 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1641 lflags |= LOOKUP_NO_CONVERSION;
1644 lflags |= LOOKUP_ONLYCONVERTING;
1646 t = implicit_conversion (parmtype, argtype, arg,
1647 /*c_cast_p=*/false, lflags);
1651 t = build_identity_conv (argtype, arg);
1652 t->ellipsis_p = true;
1669 parmnode = TREE_CHAIN (parmnode);
1673 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1674 access_path, conversion_path, viable);
1677 /* Create an overload candidate for the conversion function FN which will
1678 be invoked for expression OBJ, producing a pointer-to-function which
1679 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1680 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1681 passed on to implicit_conversion.
1683 Actually, we don't really care about FN; we care about the type it
1684 converts to. There may be multiple conversion functions that will
1685 convert to that type, and we rely on build_user_type_conversion_1 to
1686 choose the best one; so when we create our candidate, we record the type
1687 instead of the function. */
1689 static struct z_candidate *
1690 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1691 tree first_arg, const VEC(tree,gc) *arglist,
1692 tree access_path, tree conversion_path)
1694 tree totype = TREE_TYPE (TREE_TYPE (fn));
1695 int i, len, viable, flags;
1696 tree parmlist, parmnode;
1699 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1700 parmlist = TREE_TYPE (parmlist);
1701 parmlist = TYPE_ARG_TYPES (parmlist);
1703 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1704 convs = alloc_conversions (len);
1705 parmnode = parmlist;
1707 flags = LOOKUP_IMPLICIT;
1709 /* Don't bother looking up the same type twice. */
1710 if (*candidates && (*candidates)->fn == totype)
1713 for (i = 0; i < len; ++i)
1720 else if (i == 1 && first_arg != NULL_TREE)
1723 arg = VEC_index (tree, arglist,
1724 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1725 argtype = lvalue_type (arg);
1728 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1730 else if (parmnode == void_list_node)
1733 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1734 /*c_cast_p=*/false, flags);
1737 t = build_identity_conv (argtype, arg);
1738 t->ellipsis_p = true;
1752 parmnode = TREE_CHAIN (parmnode);
1758 if (!sufficient_parms_p (parmnode))
1761 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1762 access_path, conversion_path, viable);
1766 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1767 tree type1, tree type2, tree *args, tree *argtypes,
1779 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1780 convs = alloc_conversions (num_convs);
1782 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
1783 conversion ops are allowed. We handle that here by just checking for
1784 boolean_type_node because other operators don't ask for it. COND_EXPR
1785 also does contextual conversion to bool for the first operand, but we
1786 handle that in build_conditional_expr, and type1 here is operand 2. */
1787 if (type1 != boolean_type_node)
1788 flags |= LOOKUP_ONLYCONVERTING;
1790 for (i = 0; i < 2; ++i)
1795 t = implicit_conversion (types[i], argtypes[i], args[i],
1796 /*c_cast_p=*/false, flags);
1800 /* We need something for printing the candidate. */
1801 t = build_identity_conv (types[i], NULL_TREE);
1808 /* For COND_EXPR we rearranged the arguments; undo that now. */
1811 convs[2] = convs[1];
1812 convs[1] = convs[0];
1813 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1814 /*c_cast_p=*/false, flags);
1821 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1823 /*access_path=*/NULL_TREE,
1824 /*conversion_path=*/NULL_TREE,
1829 is_complete (tree t)
1831 return COMPLETE_TYPE_P (complete_type (t));
1834 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1837 promoted_arithmetic_type_p (tree type)
1841 In this section, the term promoted integral type is used to refer
1842 to those integral types which are preserved by integral promotion
1843 (including e.g. int and long but excluding e.g. char).
1844 Similarly, the term promoted arithmetic type refers to promoted
1845 integral types plus floating types. */
1846 return ((CP_INTEGRAL_TYPE_P (type)
1847 && same_type_p (type_promotes_to (type), type))
1848 || TREE_CODE (type) == REAL_TYPE);
1851 /* Create any builtin operator overload candidates for the operator in
1852 question given the converted operand types TYPE1 and TYPE2. The other
1853 args are passed through from add_builtin_candidates to
1854 build_builtin_candidate.
1856 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1857 If CODE is requires candidates operands of the same type of the kind
1858 of which TYPE1 and TYPE2 are, we add both candidates
1859 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1862 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1863 enum tree_code code2, tree fnname, tree type1,
1864 tree type2, tree *args, tree *argtypes, int flags)
1868 case POSTINCREMENT_EXPR:
1869 case POSTDECREMENT_EXPR:
1870 args[1] = integer_zero_node;
1871 type2 = integer_type_node;
1880 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1881 and VQ is either volatile or empty, there exist candidate operator
1882 functions of the form
1883 VQ T& operator++(VQ T&);
1884 T operator++(VQ T&, int);
1885 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1886 type other than bool, and VQ is either volatile or empty, there exist
1887 candidate operator functions of the form
1888 VQ T& operator--(VQ T&);
1889 T operator--(VQ T&, int);
1890 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1891 complete object type, and VQ is either volatile or empty, there exist
1892 candidate operator functions of the form
1893 T*VQ& operator++(T*VQ&);
1894 T*VQ& operator--(T*VQ&);
1895 T* operator++(T*VQ&, int);
1896 T* operator--(T*VQ&, int); */
1898 case POSTDECREMENT_EXPR:
1899 case PREDECREMENT_EXPR:
1900 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1902 case POSTINCREMENT_EXPR:
1903 case PREINCREMENT_EXPR:
1904 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1906 type1 = build_reference_type (type1);
1911 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1912 exist candidate operator functions of the form
1916 8 For every function type T, there exist candidate operator functions of
1918 T& operator*(T*); */
1921 if (TREE_CODE (type1) == POINTER_TYPE
1922 && (TYPE_PTROB_P (type1)
1923 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1927 /* 9 For every type T, there exist candidate operator functions of the form
1930 10For every promoted arithmetic type T, there exist candidate operator
1931 functions of the form
1935 case UNARY_PLUS_EXPR: /* unary + */
1936 if (TREE_CODE (type1) == POINTER_TYPE)
1939 if (ARITHMETIC_TYPE_P (type1))
1943 /* 11For every promoted integral type T, there exist candidate operator
1944 functions of the form
1948 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1952 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1953 is the same type as C2 or is a derived class of C2, T is a complete
1954 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1955 there exist candidate operator functions of the form
1956 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1957 where CV12 is the union of CV1 and CV2. */
1960 if (TREE_CODE (type1) == POINTER_TYPE
1961 && TYPE_PTR_TO_MEMBER_P (type2))
1963 tree c1 = TREE_TYPE (type1);
1964 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1966 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1967 && (TYPE_PTRMEMFUNC_P (type2)
1968 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1973 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1974 didate operator functions of the form
1979 bool operator<(L, R);
1980 bool operator>(L, R);
1981 bool operator<=(L, R);
1982 bool operator>=(L, R);
1983 bool operator==(L, R);
1984 bool operator!=(L, R);
1985 where LR is the result of the usual arithmetic conversions between
1988 14For every pair of types T and I, where T is a cv-qualified or cv-
1989 unqualified complete object type and I is a promoted integral type,
1990 there exist candidate operator functions of the form
1991 T* operator+(T*, I);
1992 T& operator[](T*, I);
1993 T* operator-(T*, I);
1994 T* operator+(I, T*);
1995 T& operator[](I, T*);
1997 15For every T, where T is a pointer to complete object type, there exist
1998 candidate operator functions of the form112)
1999 ptrdiff_t operator-(T, T);
2001 16For every pointer or enumeration type T, there exist candidate operator
2002 functions of the form
2003 bool operator<(T, T);
2004 bool operator>(T, T);
2005 bool operator<=(T, T);
2006 bool operator>=(T, T);
2007 bool operator==(T, T);
2008 bool operator!=(T, T);
2010 17For every pointer to member type T, there exist candidate operator
2011 functions of the form
2012 bool operator==(T, T);
2013 bool operator!=(T, T); */
2016 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2018 if (TYPE_PTROB_P (type1)
2019 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2021 type2 = ptrdiff_type_node;
2025 case TRUNC_DIV_EXPR:
2026 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2032 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2033 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2035 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2040 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2052 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2054 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2056 if (TREE_CODE (type1) == ENUMERAL_TYPE
2057 && TREE_CODE (type2) == ENUMERAL_TYPE)
2059 if (TYPE_PTR_P (type1)
2060 && null_ptr_cst_p (args[1])
2061 && !uses_template_parms (type1))
2066 if (null_ptr_cst_p (args[0])
2067 && TYPE_PTR_P (type2)
2068 && !uses_template_parms (type2))
2076 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2079 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2081 type1 = ptrdiff_type_node;
2084 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2086 type2 = ptrdiff_type_node;
2091 /* 18For every pair of promoted integral types L and R, there exist candi-
2092 date operator functions of the form
2099 where LR is the result of the usual arithmetic conversions between
2102 case TRUNC_MOD_EXPR:
2108 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2112 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2113 type, VQ is either volatile or empty, and R is a promoted arithmetic
2114 type, there exist candidate operator functions of the form
2115 VQ L& operator=(VQ L&, R);
2116 VQ L& operator*=(VQ L&, R);
2117 VQ L& operator/=(VQ L&, R);
2118 VQ L& operator+=(VQ L&, R);
2119 VQ L& operator-=(VQ L&, R);
2121 20For every pair T, VQ), where T is any type and VQ is either volatile
2122 or empty, there exist candidate operator functions of the form
2123 T*VQ& operator=(T*VQ&, T*);
2125 21For every pair T, VQ), where T is a pointer to member type and VQ is
2126 either volatile or empty, there exist candidate operator functions of
2128 VQ T& operator=(VQ T&, T);
2130 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2131 unqualified complete object type, VQ is either volatile or empty, and
2132 I is a promoted integral type, there exist candidate operator func-
2134 T*VQ& operator+=(T*VQ&, I);
2135 T*VQ& operator-=(T*VQ&, I);
2137 23For every triple L, VQ, R), where L is an integral or enumeration
2138 type, VQ is either volatile or empty, and R is a promoted integral
2139 type, there exist candidate operator functions of the form
2141 VQ L& operator%=(VQ L&, R);
2142 VQ L& operator<<=(VQ L&, R);
2143 VQ L& operator>>=(VQ L&, R);
2144 VQ L& operator&=(VQ L&, R);
2145 VQ L& operator^=(VQ L&, R);
2146 VQ L& operator|=(VQ L&, R); */
2153 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2155 type2 = ptrdiff_type_node;
2159 case TRUNC_DIV_EXPR:
2160 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2164 case TRUNC_MOD_EXPR:
2170 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2175 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2177 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2178 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2179 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2180 || ((TYPE_PTRMEMFUNC_P (type1)
2181 || TREE_CODE (type1) == POINTER_TYPE)
2182 && null_ptr_cst_p (args[1])))
2192 type1 = build_reference_type (type1);
2198 For every pair of promoted arithmetic types L and R, there
2199 exist candidate operator functions of the form
2201 LR operator?(bool, L, R);
2203 where LR is the result of the usual arithmetic conversions
2204 between types L and R.
2206 For every type T, where T is a pointer or pointer-to-member
2207 type, there exist candidate operator functions of the form T
2208 operator?(bool, T, T); */
2210 if (promoted_arithmetic_type_p (type1)
2211 && promoted_arithmetic_type_p (type2))
2215 /* Otherwise, the types should be pointers. */
2216 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2217 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2220 /* We don't check that the two types are the same; the logic
2221 below will actually create two candidates; one in which both
2222 parameter types are TYPE1, and one in which both parameter
2230 /* If we're dealing with two pointer types or two enumeral types,
2231 we need candidates for both of them. */
2232 if (type2 && !same_type_p (type1, type2)
2233 && TREE_CODE (type1) == TREE_CODE (type2)
2234 && (TREE_CODE (type1) == REFERENCE_TYPE
2235 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2236 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2237 || TYPE_PTRMEMFUNC_P (type1)
2238 || MAYBE_CLASS_TYPE_P (type1)
2239 || TREE_CODE (type1) == ENUMERAL_TYPE))
2241 build_builtin_candidate
2242 (candidates, fnname, type1, type1, args, argtypes, flags);
2243 build_builtin_candidate
2244 (candidates, fnname, type2, type2, args, argtypes, flags);
2248 build_builtin_candidate
2249 (candidates, fnname, type1, type2, args, argtypes, flags);
2253 type_decays_to (tree type)
2255 if (TREE_CODE (type) == ARRAY_TYPE)
2256 return build_pointer_type (TREE_TYPE (type));
2257 if (TREE_CODE (type) == FUNCTION_TYPE)
2258 return build_pointer_type (type);
2262 /* There are three conditions of builtin candidates:
2264 1) bool-taking candidates. These are the same regardless of the input.
2265 2) pointer-pair taking candidates. These are generated for each type
2266 one of the input types converts to.
2267 3) arithmetic candidates. According to the standard, we should generate
2268 all of these, but I'm trying not to...
2270 Here we generate a superset of the possible candidates for this particular
2271 case. That is a subset of the full set the standard defines, plus some
2272 other cases which the standard disallows. add_builtin_candidate will
2273 filter out the invalid set. */
2276 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2277 enum tree_code code2, tree fnname, tree *args,
2282 tree type, argtypes[3];
2283 /* TYPES[i] is the set of possible builtin-operator parameter types
2284 we will consider for the Ith argument. These are represented as
2285 a TREE_LIST; the TREE_VALUE of each node is the potential
2289 for (i = 0; i < 3; ++i)
2292 argtypes[i] = unlowered_expr_type (args[i]);
2294 argtypes[i] = NULL_TREE;
2299 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2300 and VQ is either volatile or empty, there exist candidate operator
2301 functions of the form
2302 VQ T& operator++(VQ T&); */
2304 case POSTINCREMENT_EXPR:
2305 case PREINCREMENT_EXPR:
2306 case POSTDECREMENT_EXPR:
2307 case PREDECREMENT_EXPR:
2312 /* 24There also exist candidate operator functions of the form
2313 bool operator!(bool);
2314 bool operator&&(bool, bool);
2315 bool operator||(bool, bool); */
2317 case TRUTH_NOT_EXPR:
2318 build_builtin_candidate
2319 (candidates, fnname, boolean_type_node,
2320 NULL_TREE, args, argtypes, flags);
2323 case TRUTH_ORIF_EXPR:
2324 case TRUTH_ANDIF_EXPR:
2325 build_builtin_candidate
2326 (candidates, fnname, boolean_type_node,
2327 boolean_type_node, args, argtypes, flags);
2349 types[0] = types[1] = NULL_TREE;
2351 for (i = 0; i < 2; ++i)
2355 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2359 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2362 convs = lookup_conversions (argtypes[i]);
2364 if (code == COND_EXPR)
2366 if (real_lvalue_p (args[i]))
2367 types[i] = tree_cons
2368 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2370 types[i] = tree_cons
2371 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2377 for (; convs; convs = TREE_CHAIN (convs))
2379 type = TREE_TYPE (convs);
2382 && (TREE_CODE (type) != REFERENCE_TYPE
2383 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2386 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2387 types[i] = tree_cons (NULL_TREE, type, types[i]);
2389 type = non_reference (type);
2390 if (i != 0 || ! ref1)
2392 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2393 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2394 types[i] = tree_cons (NULL_TREE, type, types[i]);
2395 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2396 type = type_promotes_to (type);
2399 if (! value_member (type, types[i]))
2400 types[i] = tree_cons (NULL_TREE, type, types[i]);
2405 if (code == COND_EXPR && real_lvalue_p (args[i]))
2406 types[i] = tree_cons
2407 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2408 type = non_reference (argtypes[i]);
2409 if (i != 0 || ! ref1)
2411 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2412 if (enum_p && UNSCOPED_ENUM_P (type))
2413 types[i] = tree_cons (NULL_TREE, type, types[i]);
2414 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2415 type = type_promotes_to (type);
2417 types[i] = tree_cons (NULL_TREE, type, types[i]);
2421 /* Run through the possible parameter types of both arguments,
2422 creating candidates with those parameter types. */
2423 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2426 for (type = types[1]; type; type = TREE_CHAIN (type))
2427 add_builtin_candidate
2428 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2429 TREE_VALUE (type), args, argtypes, flags);
2431 add_builtin_candidate
2432 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2433 NULL_TREE, args, argtypes, flags);
2438 /* If TMPL can be successfully instantiated as indicated by
2439 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2441 TMPL is the template. EXPLICIT_TARGS are any explicit template
2442 arguments. ARGLIST is the arguments provided at the call-site.
2443 This does not change ARGLIST. The RETURN_TYPE is the desired type
2444 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2445 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2446 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2448 static struct z_candidate*
2449 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2450 tree ctype, tree explicit_targs, tree first_arg,
2451 const VEC(tree,gc) *arglist, tree return_type,
2452 tree access_path, tree conversion_path,
2453 int flags, tree obj, unification_kind_t strict)
2455 int ntparms = DECL_NTPARMS (tmpl);
2456 tree targs = make_tree_vec (ntparms);
2458 int skip_without_in_chrg;
2459 tree first_arg_without_in_chrg;
2460 tree *args_without_in_chrg;
2461 unsigned int nargs_without_in_chrg;
2462 unsigned int ia, ix;
2464 struct z_candidate *cand;
2468 nargs = (first_arg == NULL_TREE ? 0 : 1) + VEC_length (tree, arglist);
2470 skip_without_in_chrg = 0;
2472 first_arg_without_in_chrg = first_arg;
2474 /* We don't do deduction on the in-charge parameter, the VTT
2475 parameter or 'this'. */
2476 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2478 if (first_arg_without_in_chrg != NULL_TREE)
2479 first_arg_without_in_chrg = NULL_TREE;
2481 ++skip_without_in_chrg;
2484 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2485 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2486 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2488 if (first_arg_without_in_chrg != NULL_TREE)
2489 first_arg_without_in_chrg = NULL_TREE;
2491 ++skip_without_in_chrg;
2494 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2495 + (VEC_length (tree, arglist)
2496 - skip_without_in_chrg));
2497 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2499 if (first_arg_without_in_chrg != NULL_TREE)
2501 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2504 for (ix = skip_without_in_chrg;
2505 VEC_iterate (tree, arglist, ix, arg);
2508 args_without_in_chrg[ia] = arg;
2511 gcc_assert (ia == nargs_without_in_chrg);
2513 i = fn_type_unification (tmpl, explicit_targs, targs,
2514 args_without_in_chrg,
2515 nargs_without_in_chrg,
2516 return_type, strict, flags);
2521 fn = instantiate_template (tmpl, targs, tf_none);
2522 if (fn == error_mark_node)
2527 A member function template is never instantiated to perform the
2528 copy of a class object to an object of its class type.
2530 It's a little unclear what this means; the standard explicitly
2531 does allow a template to be used to copy a class. For example,
2536 template <class T> A(const T&);
2539 void g () { A a (f ()); }
2541 the member template will be used to make the copy. The section
2542 quoted above appears in the paragraph that forbids constructors
2543 whose only parameter is (a possibly cv-qualified variant of) the
2544 class type, and a logical interpretation is that the intent was
2545 to forbid the instantiation of member templates which would then
2547 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2549 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2550 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2555 if (obj != NULL_TREE)
2556 /* Aha, this is a conversion function. */
2557 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2558 access_path, conversion_path);
2560 cand = add_function_candidate (candidates, fn, ctype,
2561 first_arg, arglist, access_path,
2562 conversion_path, flags);
2563 if (DECL_TI_TEMPLATE (fn) != tmpl)
2564 /* This situation can occur if a member template of a template
2565 class is specialized. Then, instantiate_template might return
2566 an instantiation of the specialization, in which case the
2567 DECL_TI_TEMPLATE field will point at the original
2568 specialization. For example:
2570 template <class T> struct S { template <class U> void f(U);
2571 template <> void f(int) {}; };
2575 Here, TMPL will be template <class U> S<double>::f(U).
2576 And, instantiate template will give us the specialization
2577 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2578 for this will point at template <class T> template <> S<T>::f(int),
2579 so that we can find the definition. For the purposes of
2580 overload resolution, however, we want the original TMPL. */
2581 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2583 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2589 static struct z_candidate *
2590 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2591 tree explicit_targs, tree first_arg,
2592 const VEC(tree,gc) *arglist, tree return_type,
2593 tree access_path, tree conversion_path, int flags,
2594 unification_kind_t strict)
2597 add_template_candidate_real (candidates, tmpl, ctype,
2598 explicit_targs, first_arg, arglist,
2599 return_type, access_path, conversion_path,
2600 flags, NULL_TREE, strict);
2604 static struct z_candidate *
2605 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2606 tree obj, tree first_arg,
2607 const VEC(tree,gc) *arglist,
2608 tree return_type, tree access_path,
2609 tree conversion_path)
2612 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2613 first_arg, arglist, return_type, access_path,
2614 conversion_path, 0, obj, DEDUCE_CONV);
2617 /* The CANDS are the set of candidates that were considered for
2618 overload resolution. Return the set of viable candidates. If none
2619 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2620 is true if a candidate should be considered viable only if it is
2623 static struct z_candidate*
2624 splice_viable (struct z_candidate *cands,
2628 struct z_candidate *viable;
2629 struct z_candidate **last_viable;
2630 struct z_candidate **cand;
2633 last_viable = &viable;
2634 *any_viable_p = false;
2639 struct z_candidate *c = *cand;
2640 if (strict_p ? c->viable == 1 : c->viable)
2645 last_viable = &c->next;
2646 *any_viable_p = true;
2652 return viable ? viable : cands;
2656 any_strictly_viable (struct z_candidate *cands)
2658 for (; cands; cands = cands->next)
2659 if (cands->viable == 1)
2664 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2665 words, it is about to become the "this" pointer for a member
2666 function call. Take the address of the object. */
2669 build_this (tree obj)
2671 /* In a template, we are only concerned about the type of the
2672 expression, so we can take a shortcut. */
2673 if (processing_template_decl)
2674 return build_address (obj);
2676 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2679 /* Returns true iff functions are equivalent. Equivalent functions are
2680 not '==' only if one is a function-local extern function or if
2681 both are extern "C". */
2684 equal_functions (tree fn1, tree fn2)
2686 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2687 || DECL_EXTERN_C_FUNCTION_P (fn1))
2688 return decls_match (fn1, fn2);
2692 /* Print information about one overload candidate CANDIDATE. MSGSTR
2693 is the text to print before the candidate itself.
2695 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2696 to have been run through gettext by the caller. This wart makes
2697 life simpler in print_z_candidates and for the translators. */
2700 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2702 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2704 if (candidate->num_convs == 3)
2705 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2706 candidate->convs[0]->type,
2707 candidate->convs[1]->type,
2708 candidate->convs[2]->type);
2709 else if (candidate->num_convs == 2)
2710 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2711 candidate->convs[0]->type,
2712 candidate->convs[1]->type);
2714 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2715 candidate->convs[0]->type);
2717 else if (TYPE_P (candidate->fn))
2718 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2719 else if (candidate->viable == -1)
2720 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2721 else if (DECL_DELETED_FN (candidate->fn))
2722 inform (input_location, "%s %+#D <deleted>", msgstr, candidate->fn);
2724 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2728 print_z_candidates (struct z_candidate *candidates)
2731 struct z_candidate *cand1;
2732 struct z_candidate **cand2;
2737 /* Remove deleted candidates. */
2739 for (cand2 = &cand1; *cand2; )
2741 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2742 && DECL_DELETED_FN ((*cand2)->fn))
2743 *cand2 = (*cand2)->next;
2745 cand2 = &(*cand2)->next;
2747 /* ...if there are any non-deleted ones. */
2751 /* There may be duplicates in the set of candidates. We put off
2752 checking this condition as long as possible, since we have no way
2753 to eliminate duplicates from a set of functions in less than n^2
2754 time. Now we are about to emit an error message, so it is more
2755 permissible to go slowly. */
2756 for (cand1 = candidates; cand1; cand1 = cand1->next)
2758 tree fn = cand1->fn;
2759 /* Skip builtin candidates and conversion functions. */
2760 if (TREE_CODE (fn) != FUNCTION_DECL)
2762 cand2 = &cand1->next;
2765 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2766 && equal_functions (fn, (*cand2)->fn))
2767 *cand2 = (*cand2)->next;
2769 cand2 = &(*cand2)->next;
2773 str = _("candidates are:");
2774 print_z_candidate (str, candidates);
2775 if (candidates->next)
2777 /* Indent successive candidates by the width of the translation
2778 of the above string. */
2779 size_t len = gcc_gettext_width (str) + 1;
2780 char *spaces = (char *) alloca (len);
2781 memset (spaces, ' ', len-1);
2782 spaces[len - 1] = '\0';
2784 candidates = candidates->next;
2787 print_z_candidate (spaces, candidates);
2788 candidates = candidates->next;
2794 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2795 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2796 the result of the conversion function to convert it to the final
2797 desired type. Merge the two sequences into a single sequence,
2798 and return the merged sequence. */
2801 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2805 gcc_assert (user_seq->kind == ck_user);
2807 /* Find the end of the second conversion sequence. */
2809 while ((*t)->kind != ck_identity)
2810 t = &((*t)->u.next);
2812 /* Replace the identity conversion with the user conversion
2816 /* The entire sequence is a user-conversion sequence. */
2817 std_seq->user_conv_p = true;
2822 /* Returns the best overload candidate to perform the requested
2823 conversion. This function is used for three the overloading situations
2824 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2825 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2826 per [dcl.init.ref], so we ignore temporary bindings. */
2828 static struct z_candidate *
2829 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2831 struct z_candidate *candidates, *cand;
2832 tree fromtype = TREE_TYPE (expr);
2833 tree ctors = NULL_TREE;
2834 tree conv_fns = NULL_TREE;
2835 conversion *conv = NULL;
2836 tree first_arg = NULL_TREE;
2837 VEC(tree,gc) *args = NULL;
2841 /* We represent conversion within a hierarchy using RVALUE_CONV and
2842 BASE_CONV, as specified by [over.best.ics]; these become plain
2843 constructor calls, as specified in [dcl.init]. */
2844 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2845 || !DERIVED_FROM_P (totype, fromtype));
2847 if (MAYBE_CLASS_TYPE_P (totype))
2848 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2850 if (MAYBE_CLASS_TYPE_P (fromtype))
2852 tree to_nonref = non_reference (totype);
2853 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2854 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2855 && DERIVED_FROM_P (to_nonref, fromtype)))
2857 /* [class.conv.fct] A conversion function is never used to
2858 convert a (possibly cv-qualified) object to the (possibly
2859 cv-qualified) same object type (or a reference to it), to a
2860 (possibly cv-qualified) base class of that type (or a
2861 reference to it)... */
2864 conv_fns = lookup_conversions (fromtype);
2868 flags |= LOOKUP_NO_CONVERSION;
2870 /* It's OK to bind a temporary for converting constructor arguments, but
2871 not in converting the return value of a conversion operator. */
2872 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2873 flags &= ~LOOKUP_NO_TEMP_BIND;
2877 ctors = BASELINK_FUNCTIONS (ctors);
2879 first_arg = build_int_cst (build_pointer_type (totype), 0);
2880 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2881 && !TYPE_HAS_LIST_CTOR (totype))
2883 args = ctor_to_vec (expr);
2884 /* We still allow more conversions within an init-list. */
2885 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2886 /* But not for the copy ctor. */
2887 |LOOKUP_NO_COPY_CTOR_CONVERSION
2888 |LOOKUP_NO_NARROWING);
2891 args = make_tree_vector_single (expr);
2893 /* We should never try to call the abstract or base constructor
2895 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2896 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2898 for (; ctors; ctors = OVL_NEXT (ctors))
2900 tree ctor = OVL_CURRENT (ctors);
2901 if (DECL_NONCONVERTING_P (ctor)
2902 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2905 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2906 cand = add_template_candidate (&candidates, ctor, totype,
2907 NULL_TREE, first_arg, args, NULL_TREE,
2908 TYPE_BINFO (totype),
2909 TYPE_BINFO (totype),
2913 cand = add_function_candidate (&candidates, ctor, totype,
2914 first_arg, args, TYPE_BINFO (totype),
2915 TYPE_BINFO (totype),
2920 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2922 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2923 set, then this is copy-initialization. In that case, "The
2924 result of the call is then used to direct-initialize the
2925 object that is the destination of the copy-initialization."
2928 We represent this in the conversion sequence with an
2929 rvalue conversion, which means a constructor call. */
2930 if (TREE_CODE (totype) != REFERENCE_TYPE
2931 && !(convflags & LOOKUP_NO_TEMP_BIND))
2933 = build_conv (ck_rvalue, totype, cand->second_conv);
2938 first_arg = build_this (expr);
2940 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2943 tree conversion_path = TREE_PURPOSE (conv_fns);
2945 /* If we are called to convert to a reference type, we are trying to
2946 find an lvalue binding, so don't even consider temporaries. If
2947 we don't find an lvalue binding, the caller will try again to
2948 look for a temporary binding. */
2949 if (TREE_CODE (totype) == REFERENCE_TYPE)
2950 convflags |= LOOKUP_NO_TEMP_BIND;
2952 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2954 tree fn = OVL_CURRENT (fns);
2956 if (DECL_NONCONVERTING_P (fn)
2957 && (flags & LOOKUP_ONLYCONVERTING))
2960 /* [over.match.funcs] For conversion functions, the function
2961 is considered to be a member of the class of the implicit
2962 object argument for the purpose of defining the type of
2963 the implicit object parameter.
2965 So we pass fromtype as CTYPE to add_*_candidate. */
2967 if (TREE_CODE (fn) == TEMPLATE_DECL)
2968 cand = add_template_candidate (&candidates, fn, fromtype,
2970 first_arg, NULL, totype,
2971 TYPE_BINFO (fromtype),
2976 cand = add_function_candidate (&candidates, fn, fromtype,
2978 TYPE_BINFO (fromtype),
2985 = implicit_conversion (totype,
2986 TREE_TYPE (TREE_TYPE (cand->fn)),
2988 /*c_cast_p=*/false, convflags);
2990 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2991 copy-initialization. In that case, "The result of the
2992 call is then used to direct-initialize the object that is
2993 the destination of the copy-initialization." [dcl.init]
2995 We represent this in the conversion sequence with an
2996 rvalue conversion, which means a constructor call. But
2997 don't add a second rvalue conversion if there's already
2998 one there. Which there really shouldn't be, but it's
2999 harmless since we'd add it here anyway. */
3000 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3001 && !(convflags & LOOKUP_NO_TEMP_BIND))
3002 ics = build_conv (ck_rvalue, totype, ics);
3004 cand->second_conv = ics;
3008 else if (candidates->viable == 1 && ics->bad_p)
3014 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3018 cand = tourney (candidates);
3021 if (flags & LOOKUP_COMPLAIN)
3023 error ("conversion from %qT to %qT is ambiguous",
3025 print_z_candidates (candidates);
3028 cand = candidates; /* any one will do */
3029 cand->second_conv = build_ambiguous_conv (totype, expr);
3030 cand->second_conv->user_conv_p = true;
3031 if (!any_strictly_viable (candidates))
3032 cand->second_conv->bad_p = true;
3033 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3034 ambiguous conversion is no worse than another user-defined
3040 /* Build the user conversion sequence. */
3043 (DECL_CONSTRUCTOR_P (cand->fn)
3044 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3045 build_identity_conv (TREE_TYPE (expr), expr));
3048 /* Remember that this was a list-initialization. */
3049 if (flags & LOOKUP_NO_NARROWING)
3050 conv->check_narrowing = true;
3052 /* Combine it with the second conversion sequence. */
3053 cand->second_conv = merge_conversion_sequences (conv,
3056 if (cand->viable == -1)
3057 cand->second_conv->bad_p = true;
3063 build_user_type_conversion (tree totype, tree expr, int flags)
3065 struct z_candidate *cand
3066 = build_user_type_conversion_1 (totype, expr, flags);
3070 if (cand->second_conv->kind == ck_ambig)
3071 return error_mark_node;
3072 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3073 return convert_from_reference (expr);
3078 /* Do any initial processing on the arguments to a function call. */
3080 static VEC(tree,gc) *
3081 resolve_args (VEC(tree,gc) *args)
3086 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3088 if (error_operand_p (arg))
3090 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3092 error ("invalid use of void expression");
3095 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3101 /* Perform overload resolution on FN, which is called with the ARGS.
3103 Return the candidate function selected by overload resolution, or
3104 NULL if the event that overload resolution failed. In the case
3105 that overload resolution fails, *CANDIDATES will be the set of
3106 candidates considered, and ANY_VIABLE_P will be set to true or
3107 false to indicate whether or not any of the candidates were
3110 The ARGS should already have gone through RESOLVE_ARGS before this
3111 function is called. */
3113 static struct z_candidate *
3114 perform_overload_resolution (tree fn,
3115 const VEC(tree,gc) *args,
3116 struct z_candidate **candidates,
3119 struct z_candidate *cand;
3120 tree explicit_targs = NULL_TREE;
3121 int template_only = 0;
3124 *any_viable_p = true;
3127 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3128 || TREE_CODE (fn) == TEMPLATE_DECL
3129 || TREE_CODE (fn) == OVERLOAD
3130 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3132 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3134 explicit_targs = TREE_OPERAND (fn, 1);
3135 fn = TREE_OPERAND (fn, 0);
3139 /* Add the various candidate functions. */
3140 add_candidates (fn, args, explicit_targs, template_only,
3141 /*conversion_path=*/NULL_TREE,
3142 /*access_path=*/NULL_TREE,
3146 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3150 cand = tourney (*candidates);
3154 /* Return an expression for a call to FN (a namespace-scope function,
3155 or a static member function) with the ARGS. This may change
3159 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3160 tsubst_flags_t complain)
3162 struct z_candidate *candidates, *cand;
3167 if (args != NULL && *args != NULL)
3169 *args = resolve_args (*args);
3171 return error_mark_node;
3174 /* If this function was found without using argument dependent
3175 lookup, then we want to ignore any undeclared friend
3181 fn = remove_hidden_names (fn);
3184 if (complain & tf_error)
3185 error ("no matching function for call to %<%D(%A)%>",
3186 DECL_NAME (OVL_CURRENT (orig_fn)),
3187 build_tree_list_vec (*args));
3188 return error_mark_node;
3192 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3193 p = conversion_obstack_alloc (0);
3195 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3199 if (complain & tf_error)
3201 if (!any_viable_p && candidates && ! candidates->next)
3202 return cp_build_function_call_vec (candidates->fn, args, complain);
3203 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3204 fn = TREE_OPERAND (fn, 0);
3206 error ("no matching function for call to %<%D(%A)%>",
3207 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3209 error ("call of overloaded %<%D(%A)%> is ambiguous",
3210 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3212 print_z_candidates (candidates);
3214 result = error_mark_node;
3217 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3219 /* Free all the conversions we allocated. */
3220 obstack_free (&conversion_obstack, p);
3225 /* Build a call to a global operator new. FNNAME is the name of the
3226 operator (either "operator new" or "operator new[]") and ARGS are
3227 the arguments provided. This may change ARGS. *SIZE points to the
3228 total number of bytes required by the allocation, and is updated if
3229 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3230 be used. If this function determines that no cookie should be
3231 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3232 non-NULL, it will be set, upon return, to the allocation function
3236 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3237 tree *size, tree *cookie_size,
3241 struct z_candidate *candidates;
3242 struct z_candidate *cand;
3247 VEC_safe_insert (tree, gc, *args, 0, *size);
3248 *args = resolve_args (*args);
3250 return error_mark_node;
3256 If this lookup fails to find the name, or if the allocated type
3257 is not a class type, the allocation function's name is looked
3258 up in the global scope.
3260 we disregard block-scope declarations of "operator new". */
3261 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3263 /* Figure out what function is being called. */
3264 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3266 /* If no suitable function could be found, issue an error message
3271 error ("no matching function for call to %<%D(%A)%>",
3272 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3274 error ("call of overloaded %<%D(%A)%> is ambiguous",
3275 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3277 print_z_candidates (candidates);
3278 return error_mark_node;
3281 /* If a cookie is required, add some extra space. Whether
3282 or not a cookie is required cannot be determined until
3283 after we know which function was called. */
3286 bool use_cookie = true;
3287 if (!abi_version_at_least (2))
3289 /* In G++ 3.2, the check was implemented incorrectly; it
3290 looked at the placement expression, rather than the
3291 type of the function. */
3292 if (VEC_length (tree, *args) == 2
3293 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3301 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3302 /* Skip the size_t parameter. */
3303 arg_types = TREE_CHAIN (arg_types);
3304 /* Check the remaining parameters (if any). */
3306 && TREE_CHAIN (arg_types) == void_list_node
3307 && same_type_p (TREE_VALUE (arg_types),
3311 /* If we need a cookie, adjust the number of bytes allocated. */
3314 /* Update the total size. */
3315 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3316 /* Update the argument list to reflect the adjusted size. */
3317 VEC_replace (tree, *args, 0, *size);
3320 *cookie_size = NULL_TREE;
3323 /* Tell our caller which function we decided to call. */
3327 /* Build the CALL_EXPR. */
3328 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3331 /* Build a new call to operator(). This may change ARGS. */
3334 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3336 struct z_candidate *candidates = 0, *cand;
3337 tree fns, convs, first_mem_arg = NULL_TREE;
3338 tree type = TREE_TYPE (obj);
3340 tree result = NULL_TREE;
3343 if (error_operand_p (obj))
3344 return error_mark_node;
3346 obj = prep_operand (obj);
3348 if (TYPE_PTRMEMFUNC_P (type))
3350 if (complain & tf_error)
3351 /* It's no good looking for an overloaded operator() on a
3352 pointer-to-member-function. */
3353 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3354 return error_mark_node;
3357 if (TYPE_BINFO (type))
3359 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3360 if (fns == error_mark_node)
3361 return error_mark_node;
3366 if (args != NULL && *args != NULL)
3368 *args = resolve_args (*args);
3370 return error_mark_node;
3373 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3374 p = conversion_obstack_alloc (0);
3378 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3379 first_mem_arg = build_this (obj);
3381 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3383 tree fn = OVL_CURRENT (fns);
3384 if (TREE_CODE (fn) == TEMPLATE_DECL)
3385 add_template_candidate (&candidates, fn, base, NULL_TREE,
3386 first_mem_arg, *args, NULL_TREE,
3389 LOOKUP_NORMAL, DEDUCE_CALL);
3391 add_function_candidate
3392 (&candidates, fn, base, first_mem_arg, *args, TYPE_BINFO (type),
3393 TYPE_BINFO (type), LOOKUP_NORMAL);
3397 convs = lookup_conversions (type);
3399 for (; convs; convs = TREE_CHAIN (convs))
3401 tree fns = TREE_VALUE (convs);
3402 tree totype = TREE_TYPE (convs);
3404 if ((TREE_CODE (totype) == POINTER_TYPE
3405 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3406 || (TREE_CODE (totype) == REFERENCE_TYPE
3407 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3408 || (TREE_CODE (totype) == REFERENCE_TYPE
3409 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3410 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3411 for (; fns; fns = OVL_NEXT (fns))
3413 tree fn = OVL_CURRENT (fns);
3415 if (DECL_NONCONVERTING_P (fn))
3418 if (TREE_CODE (fn) == TEMPLATE_DECL)
3419 add_template_conv_candidate
3420 (&candidates, fn, obj, NULL_TREE, *args, totype,
3421 /*access_path=*/NULL_TREE,
3422 /*conversion_path=*/NULL_TREE);
3424 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3425 *args, /*conversion_path=*/NULL_TREE,
3426 /*access_path=*/NULL_TREE);
3430 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3433 if (complain & tf_error)
3435 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3436 build_tree_list_vec (*args));
3437 print_z_candidates (candidates);
3439 result = error_mark_node;
3443 cand = tourney (candidates);
3446 if (complain & tf_error)
3448 error ("call of %<(%T) (%A)%> is ambiguous",
3449 TREE_TYPE (obj), build_tree_list_vec (*args));
3450 print_z_candidates (candidates);
3452 result = error_mark_node;
3454 /* Since cand->fn will be a type, not a function, for a conversion
3455 function, we must be careful not to unconditionally look at
3457 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3458 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3459 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3462 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3464 obj = convert_from_reference (obj);
3465 result = cp_build_function_call_vec (obj, args, complain);
3469 /* Free all the conversions we allocated. */
3470 obstack_free (&conversion_obstack, p);
3476 op_error (enum tree_code code, enum tree_code code2,
3477 tree arg1, tree arg2, tree arg3, const char *problem)
3481 if (code == MODIFY_EXPR)
3482 opname = assignment_operator_name_info[code2].name;
3484 opname = operator_name_info[code].name;
3489 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3490 problem, arg1, arg2, arg3);
3493 case POSTINCREMENT_EXPR:
3494 case POSTDECREMENT_EXPR:
3495 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3499 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3504 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3509 error ("%s for %<operator%s%> in %<%E %s %E%>",
3510 problem, opname, arg1, opname, arg2);
3512 error ("%s for %<operator%s%> in %<%s%E%>",
3513 problem, opname, opname, arg1);
3518 /* Return the implicit conversion sequence that could be used to
3519 convert E1 to E2 in [expr.cond]. */
3522 conditional_conversion (tree e1, tree e2)
3524 tree t1 = non_reference (TREE_TYPE (e1));
3525 tree t2 = non_reference (TREE_TYPE (e2));
3531 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3532 implicitly converted (clause _conv_) to the type "reference to
3533 T2", subject to the constraint that in the conversion the
3534 reference must bind directly (_dcl.init.ref_) to E1. */
3535 if (real_lvalue_p (e2))
3537 conv = implicit_conversion (build_reference_type (t2),
3541 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3548 If E1 and E2 have class type, and the underlying class types are
3549 the same or one is a base class of the other: E1 can be converted
3550 to match E2 if the class of T2 is the same type as, or a base
3551 class of, the class of T1, and the cv-qualification of T2 is the
3552 same cv-qualification as, or a greater cv-qualification than, the
3553 cv-qualification of T1. If the conversion is applied, E1 is
3554 changed to an rvalue of type T2 that still refers to the original
3555 source class object (or the appropriate subobject thereof). */
3556 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3557 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3559 if (good_base && at_least_as_qualified_p (t2, t1))
3561 conv = build_identity_conv (t1, e1);
3562 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3563 TYPE_MAIN_VARIANT (t2)))
3564 conv = build_conv (ck_base, t2, conv);
3566 conv = build_conv (ck_rvalue, t2, conv);
3575 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3576 converted to the type that expression E2 would have if E2 were
3577 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3578 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3582 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3583 arguments to the conditional expression. */
3586 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3587 tsubst_flags_t complain)
3591 tree result = NULL_TREE;
3592 tree result_type = NULL_TREE;
3593 bool lvalue_p = true;
3594 struct z_candidate *candidates = 0;
3595 struct z_candidate *cand;
3598 /* As a G++ extension, the second argument to the conditional can be
3599 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3600 c'.) If the second operand is omitted, make sure it is
3601 calculated only once. */
3604 if (complain & tf_error)
3605 pedwarn (input_location, OPT_pedantic,
3606 "ISO C++ forbids omitting the middle term of a ?: expression");
3608 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3609 if (real_lvalue_p (arg1))
3610 arg2 = arg1 = stabilize_reference (arg1);
3612 arg2 = arg1 = save_expr (arg1);
3617 The first expression is implicitly converted to bool (clause
3619 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
3622 /* If something has already gone wrong, just pass that fact up the
3624 if (error_operand_p (arg1)
3625 || error_operand_p (arg2)
3626 || error_operand_p (arg3))
3627 return error_mark_node;
3631 If either the second or the third operand has type (possibly
3632 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3633 array-to-pointer (_conv.array_), and function-to-pointer
3634 (_conv.func_) standard conversions are performed on the second
3635 and third operands. */
3636 arg2_type = unlowered_expr_type (arg2);
3637 arg3_type = unlowered_expr_type (arg3);
3638 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3640 /* Do the conversions. We don't these for `void' type arguments
3641 since it can't have any effect and since decay_conversion
3642 does not handle that case gracefully. */
3643 if (!VOID_TYPE_P (arg2_type))
3644 arg2 = decay_conversion (arg2);
3645 if (!VOID_TYPE_P (arg3_type))
3646 arg3 = decay_conversion (arg3);
3647 arg2_type = TREE_TYPE (arg2);
3648 arg3_type = TREE_TYPE (arg3);
3652 One of the following shall hold:
3654 --The second or the third operand (but not both) is a
3655 throw-expression (_except.throw_); the result is of the
3656 type of the other and is an rvalue.
3658 --Both the second and the third operands have type void; the
3659 result is of type void and is an rvalue.
3661 We must avoid calling force_rvalue for expressions of type
3662 "void" because it will complain that their value is being
3664 if (TREE_CODE (arg2) == THROW_EXPR
3665 && TREE_CODE (arg3) != THROW_EXPR)
3667 if (!VOID_TYPE_P (arg3_type))
3668 arg3 = force_rvalue (arg3);
3669 arg3_type = TREE_TYPE (arg3);
3670 result_type = arg3_type;
3672 else if (TREE_CODE (arg2) != THROW_EXPR
3673 && TREE_CODE (arg3) == THROW_EXPR)
3675 if (!VOID_TYPE_P (arg2_type))
3676 arg2 = force_rvalue (arg2);
3677 arg2_type = TREE_TYPE (arg2);
3678 result_type = arg2_type;
3680 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3681 result_type = void_type_node;
3684 if (complain & tf_error)
3686 if (VOID_TYPE_P (arg2_type))
3687 error ("second operand to the conditional operator "
3688 "is of type %<void%>, "
3689 "but the third operand is neither a throw-expression "
3690 "nor of type %<void%>");
3692 error ("third operand to the conditional operator "
3693 "is of type %<void%>, "
3694 "but the second operand is neither a throw-expression "
3695 "nor of type %<void%>");
3697 return error_mark_node;
3701 goto valid_operands;
3705 Otherwise, if the second and third operand have different types,
3706 and either has (possibly cv-qualified) class type, an attempt is
3707 made to convert each of those operands to the type of the other. */
3708 else if (!same_type_p (arg2_type, arg3_type)
3709 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3714 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3715 p = conversion_obstack_alloc (0);
3717 conv2 = conditional_conversion (arg2, arg3);
3718 conv3 = conditional_conversion (arg3, arg2);
3722 If both can be converted, or one can be converted but the
3723 conversion is ambiguous, the program is ill-formed. If
3724 neither can be converted, the operands are left unchanged and
3725 further checking is performed as described below. If exactly
3726 one conversion is possible, that conversion is applied to the
3727 chosen operand and the converted operand is used in place of
3728 the original operand for the remainder of this section. */
3729 if ((conv2 && !conv2->bad_p
3730 && conv3 && !conv3->bad_p)
3731 || (conv2 && conv2->kind == ck_ambig)
3732 || (conv3 && conv3->kind == ck_ambig))
3734 error ("operands to ?: have different types %qT and %qT",
3735 arg2_type, arg3_type);
3736 result = error_mark_node;
3738 else if (conv2 && (!conv2->bad_p || !conv3))
3740 arg2 = convert_like (conv2, arg2, complain);
3741 arg2 = convert_from_reference (arg2);
3742 arg2_type = TREE_TYPE (arg2);
3743 /* Even if CONV2 is a valid conversion, the result of the
3744 conversion may be invalid. For example, if ARG3 has type
3745 "volatile X", and X does not have a copy constructor
3746 accepting a "volatile X&", then even if ARG2 can be
3747 converted to X, the conversion will fail. */
3748 if (error_operand_p (arg2))
3749 result = error_mark_node;
3751 else if (conv3 && (!conv3->bad_p || !conv2))
3753 arg3 = convert_like (conv3, arg3, complain);
3754 arg3 = convert_from_reference (arg3);
3755 arg3_type = TREE_TYPE (arg3);
3756 if (error_operand_p (arg3))
3757 result = error_mark_node;
3760 /* Free all the conversions we allocated. */
3761 obstack_free (&conversion_obstack, p);
3766 /* If, after the conversion, both operands have class type,
3767 treat the cv-qualification of both operands as if it were the
3768 union of the cv-qualification of the operands.
3770 The standard is not clear about what to do in this
3771 circumstance. For example, if the first operand has type
3772 "const X" and the second operand has a user-defined
3773 conversion to "volatile X", what is the type of the second
3774 operand after this step? Making it be "const X" (matching
3775 the first operand) seems wrong, as that discards the
3776 qualification without actually performing a copy. Leaving it
3777 as "volatile X" seems wrong as that will result in the
3778 conditional expression failing altogether, even though,
3779 according to this step, the one operand could be converted to
3780 the type of the other. */
3781 if ((conv2 || conv3)
3782 && CLASS_TYPE_P (arg2_type)
3783 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3784 arg2_type = arg3_type =
3785 cp_build_qualified_type (arg2_type,
3786 TYPE_QUALS (arg2_type)
3787 | TYPE_QUALS (arg3_type));
3792 If the second and third operands are lvalues and have the same
3793 type, the result is of that type and is an lvalue. */
3794 if (real_lvalue_p (arg2)
3795 && real_lvalue_p (arg3)
3796 && same_type_p (arg2_type, arg3_type))
3798 result_type = arg2_type;
3799 goto valid_operands;
3804 Otherwise, the result is an rvalue. If the second and third
3805 operand do not have the same type, and either has (possibly
3806 cv-qualified) class type, overload resolution is used to
3807 determine the conversions (if any) to be applied to the operands
3808 (_over.match.oper_, _over.built_). */
3810 if (!same_type_p (arg2_type, arg3_type)
3811 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3817 /* Rearrange the arguments so that add_builtin_candidate only has
3818 to know about two args. In build_builtin_candidate, the
3819 arguments are unscrambled. */
3823 add_builtin_candidates (&candidates,
3826 ansi_opname (COND_EXPR),
3832 If the overload resolution fails, the program is
3834 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3837 if (complain & tf_error)
3839 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3840 print_z_candidates (candidates);
3842 return error_mark_node;
3844 cand = tourney (candidates);
3847 if (complain & tf_error)
3849 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3850 print_z_candidates (candidates);
3852 return error_mark_node;
3857 Otherwise, the conversions thus determined are applied, and
3858 the converted operands are used in place of the original
3859 operands for the remainder of this section. */
3860 conv = cand->convs[0];
3861 arg1 = convert_like (conv, arg1, complain);
3862 conv = cand->convs[1];
3863 arg2 = convert_like (conv, arg2, complain);
3864 arg2_type = TREE_TYPE (arg2);
3865 conv = cand->convs[2];
3866 arg3 = convert_like (conv, arg3, complain);
3867 arg3_type = TREE_TYPE (arg3);
3872 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3873 and function-to-pointer (_conv.func_) standard conversions are
3874 performed on the second and third operands.
3876 We need to force the lvalue-to-rvalue conversion here for class types,
3877 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3878 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3881 arg2 = force_rvalue (arg2);
3882 if (!CLASS_TYPE_P (arg2_type))
3883 arg2_type = TREE_TYPE (arg2);
3885 arg3 = force_rvalue (arg3);
3886 if (!CLASS_TYPE_P (arg3_type))
3887 arg3_type = TREE_TYPE (arg3);
3889 if (arg2 == error_mark_node || arg3 == error_mark_node)
3890 return error_mark_node;
3894 After those conversions, one of the following shall hold:
3896 --The second and third operands have the same type; the result is of
3898 if (same_type_p (arg2_type, arg3_type))
3899 result_type = arg2_type;
3902 --The second and third operands have arithmetic or enumeration
3903 type; the usual arithmetic conversions are performed to bring
3904 them to a common type, and the result is of that type. */
3905 else if ((ARITHMETIC_TYPE_P (arg2_type)
3906 || UNSCOPED_ENUM_P (arg2_type))
3907 && (ARITHMETIC_TYPE_P (arg3_type)
3908 || UNSCOPED_ENUM_P (arg3_type)))
3910 /* In this case, there is always a common type. */
3911 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3914 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3915 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3917 if (complain & tf_warning)
3919 "enumeral mismatch in conditional expression: %qT vs %qT",
3920 arg2_type, arg3_type);
3922 else if (extra_warnings
3923 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3924 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3925 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3926 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3928 if (complain & tf_warning)
3930 "enumeral and non-enumeral type in conditional expression");
3933 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3934 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3938 --The second and third operands have pointer type, or one has
3939 pointer type and the other is a null pointer constant; pointer
3940 conversions (_conv.ptr_) and qualification conversions
3941 (_conv.qual_) are performed to bring them to their composite
3942 pointer type (_expr.rel_). The result is of the composite
3945 --The second and third operands have pointer to member type, or
3946 one has pointer to member type and the other is a null pointer
3947 constant; pointer to member conversions (_conv.mem_) and
3948 qualification conversions (_conv.qual_) are performed to bring
3949 them to a common type, whose cv-qualification shall match the
3950 cv-qualification of either the second or the third operand.
3951 The result is of the common type. */
3952 else if ((null_ptr_cst_p (arg2)
3953 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3954 || (null_ptr_cst_p (arg3)
3955 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3956 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3957 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3958 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3960 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3961 arg3, "conditional expression",
3963 if (result_type == error_mark_node)
3964 return error_mark_node;
3965 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3966 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3971 if (complain & tf_error)
3972 error ("operands to ?: have different types %qT and %qT",
3973 arg2_type, arg3_type);
3974 return error_mark_node;
3978 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3980 /* We can't use result_type below, as fold might have returned a
3985 /* Expand both sides into the same slot, hopefully the target of
3986 the ?: expression. We used to check for TARGET_EXPRs here,
3987 but now we sometimes wrap them in NOP_EXPRs so the test would
3989 if (CLASS_TYPE_P (TREE_TYPE (result)))
3990 result = get_target_expr (result);
3991 /* If this expression is an rvalue, but might be mistaken for an
3992 lvalue, we must add a NON_LVALUE_EXPR. */
3993 result = rvalue (result);
3999 /* OPERAND is an operand to an expression. Perform necessary steps
4000 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4004 prep_operand (tree operand)
4008 if (CLASS_TYPE_P (TREE_TYPE (operand))
4009 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4010 /* Make sure the template type is instantiated now. */
4011 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4017 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4018 OVERLOAD) to the CANDIDATES, returning an updated list of
4019 CANDIDATES. The ARGS are the arguments provided to the call,
4020 without any implicit object parameter. This may change ARGS. The
4021 EXPLICIT_TARGS are explicit template arguments provided.
4022 TEMPLATE_ONLY is true if only template functions should be
4023 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4024 add_function_candidate. */
4027 add_candidates (tree fns, const VEC(tree,gc) *args,
4028 tree explicit_targs, bool template_only,
4029 tree conversion_path, tree access_path,
4031 struct z_candidate **candidates)
4034 VEC(tree,gc) *non_static_args;
4037 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4038 /* Delay creating the implicit this parameter until it is needed. */
4039 non_static_args = NULL;
4040 first_arg = NULL_TREE;
4046 const VEC(tree,gc) *fn_args;
4048 fn = OVL_CURRENT (fns);
4049 /* Figure out which set of arguments to use. */
4050 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4052 /* If this function is a non-static member, prepend the implicit
4053 object parameter. */
4054 if (non_static_args == NULL)
4059 non_static_args = VEC_alloc (tree, gc,
4060 VEC_length (tree, args) - 1);
4061 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4062 VEC_quick_push (tree, non_static_args, arg);
4064 if (first_arg == NULL_TREE)
4065 first_arg = build_this (VEC_index (tree, args, 0));
4066 fn_first_arg = first_arg;
4067 fn_args = non_static_args;
4071 /* Otherwise, just use the list of arguments provided. */
4072 fn_first_arg = NULL_TREE;
4076 if (TREE_CODE (fn) == TEMPLATE_DECL)
4077 add_template_candidate (candidates,
4088 else if (!template_only)
4089 add_function_candidate (candidates,
4097 fns = OVL_NEXT (fns);
4101 /* Even unsigned enum types promote to signed int. We don't want to
4102 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4103 original argument and ARG is the argument after any conversions
4104 have been applied. We set TREE_NO_WARNING if we have added a cast
4105 from an unsigned enum type to a signed integer type. */
4108 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4110 if (orig_arg != NULL_TREE
4113 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4114 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4115 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4116 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4117 TREE_NO_WARNING (arg) = 1;
4121 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4122 bool *overloaded_p, tsubst_flags_t complain)
4124 tree orig_arg1 = arg1;
4125 tree orig_arg2 = arg2;
4126 tree orig_arg3 = arg3;
4127 struct z_candidate *candidates = 0, *cand;
4128 VEC(tree,gc) *arglist;
4131 tree result = NULL_TREE;
4132 bool result_valid_p = false;
4133 enum tree_code code2 = NOP_EXPR;
4134 enum tree_code code_orig_arg1 = ERROR_MARK;
4135 enum tree_code code_orig_arg2 = ERROR_MARK;
4141 if (error_operand_p (arg1)
4142 || error_operand_p (arg2)
4143 || error_operand_p (arg3))
4144 return error_mark_node;
4146 if (code == MODIFY_EXPR)
4148 code2 = TREE_CODE (arg3);
4150 fnname = ansi_assopname (code2);
4153 fnname = ansi_opname (code);
4155 arg1 = prep_operand (arg1);
4161 case VEC_DELETE_EXPR:
4163 /* Use build_op_new_call and build_op_delete_call instead. */
4167 /* Use build_op_call instead. */
4170 case TRUTH_ORIF_EXPR:
4171 case TRUTH_ANDIF_EXPR:
4172 case TRUTH_AND_EXPR:
4174 /* These are saved for the sake of warn_logical_operator. */
4175 code_orig_arg1 = TREE_CODE (arg1);
4176 code_orig_arg2 = TREE_CODE (arg2);
4182 arg2 = prep_operand (arg2);
4183 arg3 = prep_operand (arg3);
4185 if (code == COND_EXPR)
4186 /* Use build_conditional_expr instead. */
4188 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4189 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4192 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4193 arg2 = integer_zero_node;
4195 arglist = VEC_alloc (tree, gc, 3);
4196 VEC_quick_push (tree, arglist, arg1);
4197 if (arg2 != NULL_TREE)
4198 VEC_quick_push (tree, arglist, arg2);
4199 if (arg3 != NULL_TREE)
4200 VEC_quick_push (tree, arglist, arg3);
4202 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4203 p = conversion_obstack_alloc (0);
4205 /* Add namespace-scope operators to the list of functions to
4207 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4208 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4209 flags, &candidates);
4210 /* Add class-member operators to the candidate set. */
4211 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4215 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4216 if (fns == error_mark_node)
4218 result = error_mark_node;
4219 goto user_defined_result_ready;
4222 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4224 BASELINK_BINFO (fns),
4225 TYPE_BINFO (TREE_TYPE (arg1)),
4226 flags, &candidates);
4231 args[2] = NULL_TREE;
4233 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4239 /* For these, the built-in candidates set is empty
4240 [over.match.oper]/3. We don't want non-strict matches
4241 because exact matches are always possible with built-in
4242 operators. The built-in candidate set for COMPONENT_REF
4243 would be empty too, but since there are no such built-in
4244 operators, we accept non-strict matches for them. */
4249 strict_p = pedantic;
4253 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4258 case POSTINCREMENT_EXPR:
4259 case POSTDECREMENT_EXPR:
4260 /* Don't try anything fancy if we're not allowed to produce
4262 if (!(complain & tf_error))
4263 return error_mark_node;
4265 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4266 distinguish between prefix and postfix ++ and
4267 operator++() was used for both, so we allow this with
4269 if (flags & LOOKUP_COMPLAIN)
4271 const char *msg = (flag_permissive)
4272 ? G_("no %<%D(int)%> declared for postfix %qs,"
4273 " trying prefix operator instead")
4274 : G_("no %<%D(int)%> declared for postfix %qs");
4275 permerror (input_location, msg, fnname,
4276 operator_name_info[code].name);
4279 if (!flag_permissive)
4280 return error_mark_node;
4282 if (code == POSTINCREMENT_EXPR)
4283 code = PREINCREMENT_EXPR;
4285 code = PREDECREMENT_EXPR;
4286 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4287 overloaded_p, complain);
4290 /* The caller will deal with these. */
4295 result_valid_p = true;
4299 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4301 /* If one of the arguments of the operator represents
4302 an invalid use of member function pointer, try to report
4303 a meaningful error ... */
4304 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4305 || invalid_nonstatic_memfn_p (arg2, tf_error)
4306 || invalid_nonstatic_memfn_p (arg3, tf_error))
4307 /* We displayed the error message. */;
4310 /* ... Otherwise, report the more generic
4311 "no matching operator found" error */
4312 op_error (code, code2, arg1, arg2, arg3, "no match");
4313 print_z_candidates (candidates);
4316 result = error_mark_node;
4322 cand = tourney (candidates);
4325 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4327 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4328 print_z_candidates (candidates);
4330 result = error_mark_node;
4332 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4335 *overloaded_p = true;
4337 if (resolve_args (arglist) == NULL)
4338 result = error_mark_node;
4340 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4344 /* Give any warnings we noticed during overload resolution. */
4345 if (cand->warnings && (complain & tf_warning))
4347 struct candidate_warning *w;
4348 for (w = cand->warnings; w; w = w->next)
4349 joust (cand, w->loser, 1);
4352 /* Check for comparison of different enum types. */
4361 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4362 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4363 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4364 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4365 && (complain & tf_warning))
4367 warning (OPT_Wenum_compare,
4368 "comparison between %q#T and %q#T",
4369 TREE_TYPE (arg1), TREE_TYPE (arg2));
4376 /* We need to strip any leading REF_BIND so that bitfields
4377 don't cause errors. This should not remove any important
4378 conversions, because builtins don't apply to class
4379 objects directly. */
4380 conv = cand->convs[0];
4381 if (conv->kind == ck_ref_bind)
4382 conv = conv->u.next;
4383 arg1 = convert_like (conv, arg1, complain);
4387 /* We need to call warn_logical_operator before
4388 converting arg2 to a boolean_type. */
4389 if (complain & tf_warning)
4390 warn_logical_operator (input_location, code, boolean_type_node,
4391 code_orig_arg1, arg1,
4392 code_orig_arg2, arg2);
4394 conv = cand->convs[1];
4395 if (conv->kind == ck_ref_bind)
4396 conv = conv->u.next;
4397 arg2 = convert_like (conv, arg2, complain);
4401 conv = cand->convs[2];
4402 if (conv->kind == ck_ref_bind)
4403 conv = conv->u.next;
4404 arg3 = convert_like (conv, arg3, complain);
4410 user_defined_result_ready:
4412 /* Free all the conversions we allocated. */
4413 obstack_free (&conversion_obstack, p);
4415 if (result || result_valid_p)
4419 avoid_sign_compare_warnings (orig_arg1, arg1);
4420 avoid_sign_compare_warnings (orig_arg2, arg2);
4421 avoid_sign_compare_warnings (orig_arg3, arg3);
4426 return cp_build_modify_expr (arg1, code2, arg2, complain);
4429 return cp_build_indirect_ref (arg1, "unary *", complain);
4431 case TRUTH_ANDIF_EXPR:
4432 case TRUTH_ORIF_EXPR:
4433 case TRUTH_AND_EXPR:
4435 warn_logical_operator (input_location, code, boolean_type_node,
4436 code_orig_arg1, arg1, code_orig_arg2, arg2);
4441 case TRUNC_DIV_EXPR:
4452 case TRUNC_MOD_EXPR:
4456 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4458 case UNARY_PLUS_EXPR:
4461 case TRUTH_NOT_EXPR:
4462 case PREINCREMENT_EXPR:
4463 case POSTINCREMENT_EXPR:
4464 case PREDECREMENT_EXPR:
4465 case POSTDECREMENT_EXPR:
4468 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4471 return build_array_ref (input_location, arg1, arg2);
4474 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4478 /* The caller will deal with these. */
4490 /* Build a call to operator delete. This has to be handled very specially,
4491 because the restrictions on what signatures match are different from all
4492 other call instances. For a normal delete, only a delete taking (void *)
4493 or (void *, size_t) is accepted. For a placement delete, only an exact
4494 match with the placement new is accepted.
4496 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4497 ADDR is the pointer to be deleted.
4498 SIZE is the size of the memory block to be deleted.
4499 GLOBAL_P is true if the delete-expression should not consider
4500 class-specific delete operators.
4501 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4503 If this call to "operator delete" is being generated as part to
4504 deallocate memory allocated via a new-expression (as per [expr.new]
4505 which requires that if the initialization throws an exception then
4506 we call a deallocation function), then ALLOC_FN is the allocation
4510 build_op_delete_call (enum tree_code code, tree addr, tree size,
4511 bool global_p, tree placement,
4514 tree fn = NULL_TREE;
4515 tree fns, fnname, argtypes, type;
4518 if (addr == error_mark_node)
4519 return error_mark_node;
4521 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4523 fnname = ansi_opname (code);
4525 if (CLASS_TYPE_P (type)
4526 && COMPLETE_TYPE_P (complete_type (type))
4530 If the result of the lookup is ambiguous or inaccessible, or if
4531 the lookup selects a placement deallocation function, the
4532 program is ill-formed.
4534 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4536 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4537 if (fns == error_mark_node)
4538 return error_mark_node;
4543 if (fns == NULL_TREE)
4544 fns = lookup_name_nonclass (fnname);
4546 /* Strip const and volatile from addr. */
4547 addr = cp_convert (ptr_type_node, addr);
4551 /* Get the parameter types for the allocation function that is
4553 gcc_assert (alloc_fn != NULL_TREE);
4554 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4558 /* First try it without the size argument. */
4559 argtypes = void_list_node;
4562 /* We make two tries at finding a matching `operator delete'. On
4563 the first pass, we look for a one-operator (or placement)
4564 operator delete. If we're not doing placement delete, then on
4565 the second pass we look for a two-argument delete. */
4566 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4568 /* Go through the `operator delete' functions looking for one
4569 with a matching type. */
4570 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4576 /* The first argument must be "void *". */
4577 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4578 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4581 /* On the first pass, check the rest of the arguments. */
4587 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4595 /* On the second pass, look for a function with exactly two
4596 arguments: "void *" and "size_t". */
4598 /* For "operator delete(void *, ...)" there will be
4599 no second argument, but we will not get an exact
4602 && same_type_p (TREE_VALUE (t), size_type_node)
4603 && TREE_CHAIN (t) == void_list_node)
4607 /* If we found a match, we're done. */
4612 /* If we have a matching function, call it. */
4615 /* Make sure we have the actual function, and not an
4617 fn = OVL_CURRENT (fn);
4619 /* If the FN is a member function, make sure that it is
4621 if (DECL_CLASS_SCOPE_P (fn))
4622 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4624 /* Core issue 901: It's ok to new a type with deleted delete. */
4625 if (DECL_DELETED_FN (fn) && alloc_fn)
4630 /* The placement args might not be suitable for overload
4631 resolution at this point, so build the call directly. */
4632 int nargs = call_expr_nargs (placement);
4633 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4636 for (i = 1; i < nargs; i++)
4637 argarray[i] = CALL_EXPR_ARG (placement, i);
4639 return build_cxx_call (fn, nargs, argarray);
4644 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4645 VEC_quick_push (tree, args, addr);
4647 VEC_quick_push (tree, args, size);
4648 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4649 VEC_free (tree, gc, args);
4656 If no unambiguous matching deallocation function can be found,
4657 propagating the exception does not cause the object's memory to
4662 warning (0, "no corresponding deallocation function for %qD",
4667 error ("no suitable %<operator %s%> for %qT",
4668 operator_name_info[(int)code].name, type);
4669 return error_mark_node;
4672 /* If the current scope isn't allowed to access DECL along
4673 BASETYPE_PATH, give an error. The most derived class in
4674 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4675 the declaration to use in the error diagnostic. */
4678 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4680 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4682 if (!accessible_p (basetype_path, decl, true))
4684 if (TREE_PRIVATE (decl))
4685 error ("%q+#D is private", diag_decl);
4686 else if (TREE_PROTECTED (decl))
4687 error ("%q+#D is protected", diag_decl);
4689 error ("%q+#D is inaccessible", diag_decl);
4690 error ("within this context");
4697 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4698 bitwise or of LOOKUP_* values. If any errors are warnings are
4699 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4700 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4704 build_temp (tree expr, tree type, int flags,
4705 diagnostic_t *diagnostic_kind)
4710 savew = warningcount, savee = errorcount;
4711 args = make_tree_vector_single (expr);
4712 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4713 &args, type, flags, tf_warning_or_error);
4714 release_tree_vector (args);
4715 if (warningcount > savew)
4716 *diagnostic_kind = DK_WARNING;
4717 else if (errorcount > savee)
4718 *diagnostic_kind = DK_ERROR;
4720 *diagnostic_kind = DK_UNSPECIFIED;
4724 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4725 EXPR is implicitly converted to type TOTYPE.
4726 FN and ARGNUM are used for diagnostics. */
4729 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4731 tree t = non_reference (totype);
4733 /* Issue warnings about peculiar, but valid, uses of NULL. */
4734 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4737 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4740 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4743 /* Issue warnings if "false" is converted to a NULL pointer */
4744 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4745 warning (OPT_Wconversion,
4746 "converting %<false%> to pointer type for argument %P of %qD",
4750 /* Perform the conversions in CONVS on the expression EXPR. FN and
4751 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4752 indicates the `this' argument of a method. INNER is nonzero when
4753 being called to continue a conversion chain. It is negative when a
4754 reference binding will be applied, positive otherwise. If
4755 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4756 conversions will be emitted if appropriate. If C_CAST_P is true,
4757 this conversion is coming from a C-style cast; in that case,
4758 conversions to inaccessible bases are permitted. */
4761 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4762 int inner, bool issue_conversion_warnings,
4763 bool c_cast_p, tsubst_flags_t complain)
4765 tree totype = convs->type;
4766 diagnostic_t diag_kind;
4770 && convs->kind != ck_user
4771 && convs->kind != ck_list
4772 && convs->kind != ck_ambig
4773 && convs->kind != ck_ref_bind
4774 && convs->kind != ck_rvalue
4775 && convs->kind != ck_base)
4777 conversion *t = convs;
4779 /* Give a helpful error if this is bad because of excess braces. */
4780 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4781 && SCALAR_TYPE_P (totype)
4782 && CONSTRUCTOR_NELTS (expr) > 0
4783 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4784 permerror (input_location, "too many braces around initializer for %qT", totype);
4786 for (; t; t = convs->u.next)
4788 if (t->kind == ck_user || !t->bad_p)
4790 expr = convert_like_real (t, expr, fn, argnum, 1,
4791 /*issue_conversion_warnings=*/false,
4796 else if (t->kind == ck_ambig)
4797 return convert_like_real (t, expr, fn, argnum, 1,
4798 /*issue_conversion_warnings=*/false,
4801 else if (t->kind == ck_identity)
4804 if (complain & tf_error)
4806 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4808 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4811 return error_mark_node;
4813 return cp_convert (totype, expr);
4816 if (issue_conversion_warnings && (complain & tf_warning))
4817 conversion_null_warnings (totype, expr, fn, argnum);
4819 switch (convs->kind)
4823 struct z_candidate *cand = convs->cand;
4824 tree convfn = cand->fn;
4827 /* When converting from an init list we consider explicit
4828 constructors, but actually trying to call one is an error. */
4829 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4831 if (complain & tf_error)
4832 error ("converting to %qT from initializer list would use "
4833 "explicit constructor %qD", totype, convfn);
4835 return error_mark_node;
4838 /* Set user_conv_p on the argument conversions, so rvalue/base
4839 handling knows not to allow any more UDCs. */
4840 for (i = 0; i < cand->num_convs; ++i)
4841 cand->convs[i]->user_conv_p = true;
4843 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4845 /* If this is a constructor or a function returning an aggr type,
4846 we need to build up a TARGET_EXPR. */
4847 if (DECL_CONSTRUCTOR_P (convfn))
4849 expr = build_cplus_new (totype, expr);
4851 /* Remember that this was list-initialization. */
4852 if (convs->check_narrowing)
4853 TARGET_EXPR_LIST_INIT_P (expr) = true;
4859 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4861 int nelts = CONSTRUCTOR_NELTS (expr);
4863 expr = integer_zero_node;
4864 else if (nelts == 1)
4865 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4870 if (type_unknown_p (expr))
4871 expr = instantiate_type (totype, expr, complain);
4872 /* Convert a constant to its underlying value, unless we are
4873 about to bind it to a reference, in which case we need to
4874 leave it as an lvalue. */
4877 expr = decl_constant_value (expr);
4878 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4879 /* If __null has been converted to an integer type, we do not
4880 want to warn about uses of EXPR as an integer, rather than
4882 expr = build_int_cst (totype, 0);
4886 /* Call build_user_type_conversion again for the error. */
4887 return build_user_type_conversion
4888 (totype, convs->u.expr, LOOKUP_NORMAL);
4892 /* Conversion to std::initializer_list<T>. */
4893 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4894 tree new_ctor = build_constructor (init_list_type_node, NULL);
4895 unsigned len = CONSTRUCTOR_NELTS (expr);
4897 VEC(tree,gc) *parms;
4900 /* Convert all the elements. */
4901 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4903 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4904 1, false, false, complain);
4905 if (sub == error_mark_node)
4907 check_narrowing (TREE_TYPE (sub), val);
4908 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4910 /* Build up the array. */
4911 elttype = cp_build_qualified_type
4912 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4913 array = build_array_of_n_type (elttype, len);
4914 array = finish_compound_literal (array, new_ctor);
4916 parms = make_tree_vector ();
4917 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4918 VEC_safe_push (tree, gc, parms, size_int (len));
4919 /* Call the private constructor. */
4920 push_deferring_access_checks (dk_no_check);
4921 new_ctor = build_special_member_call
4922 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4923 release_tree_vector (parms);
4924 pop_deferring_access_checks ();
4925 return build_cplus_new (totype, new_ctor);
4929 return get_target_expr (digest_init (totype, expr));
4935 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4936 convs->kind == ck_ref_bind ? -1 : 1,
4937 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4940 if (expr == error_mark_node)
4941 return error_mark_node;
4943 switch (convs->kind)
4946 expr = convert_bitfield_to_declared_type (expr);
4947 if (! MAYBE_CLASS_TYPE_P (totype))
4949 /* Else fall through. */
4951 if (convs->kind == ck_base && !convs->need_temporary_p)
4953 /* We are going to bind a reference directly to a base-class
4954 subobject of EXPR. */
4955 /* Build an expression for `*((base*) &expr)'. */
4956 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4957 expr = convert_to_base (expr, build_pointer_type (totype),
4958 !c_cast_p, /*nonnull=*/true);
4959 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4963 /* Copy-initialization where the cv-unqualified version of the source
4964 type is the same class as, or a derived class of, the class of the
4965 destination [is treated as direct-initialization]. [dcl.init] */
4966 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4967 if (convs->user_conv_p)
4968 /* This conversion is being done in the context of a user-defined
4969 conversion (i.e. the second step of copy-initialization), so
4970 don't allow any more. */
4971 flags |= LOOKUP_NO_CONVERSION;
4972 expr = build_temp (expr, totype, flags, &diag_kind);
4973 if (diag_kind && fn)
4975 if ((complain & tf_error))
4976 emit_diagnostic (diag_kind, input_location, 0,
4977 " initializing argument %P of %qD", argnum, fn);
4978 else if (diag_kind == DK_ERROR)
4979 return error_mark_node;
4981 return build_cplus_new (totype, expr);
4985 tree ref_type = totype;
4987 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
4988 && real_lvalue_p (expr))
4990 if (complain & tf_error)
4992 error ("cannot bind %qT lvalue to %qT",
4993 TREE_TYPE (expr), totype);
4995 error (" initializing argument %P of %q+D", argnum, fn);
4997 return error_mark_node;
5000 /* If necessary, create a temporary.
5002 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5003 that need temporaries, even when their types are reference
5004 compatible with the type of reference being bound, so the
5005 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5007 if (convs->need_temporary_p
5008 || TREE_CODE (expr) == CONSTRUCTOR
5009 || TREE_CODE (expr) == VA_ARG_EXPR)
5011 tree type = convs->u.next->type;
5012 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5014 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
5015 && !TYPE_REF_IS_RVALUE (ref_type))
5017 if (complain & tf_error)
5019 /* If the reference is volatile or non-const, we
5020 cannot create a temporary. */
5021 if (lvalue & clk_bitfield)
5022 error ("cannot bind bitfield %qE to %qT",
5024 else if (lvalue & clk_packed)
5025 error ("cannot bind packed field %qE to %qT",
5028 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5030 return error_mark_node;
5032 /* If the source is a packed field, and we must use a copy
5033 constructor, then building the target expr will require
5034 binding the field to the reference parameter to the
5035 copy constructor, and we'll end up with an infinite
5036 loop. If we can use a bitwise copy, then we'll be
5038 if ((lvalue & clk_packed)
5039 && CLASS_TYPE_P (type)
5040 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
5042 if (complain & tf_error)
5043 error ("cannot bind packed field %qE to %qT",
5045 return error_mark_node;
5047 if (lvalue & clk_bitfield)
5049 expr = convert_bitfield_to_declared_type (expr);
5050 expr = fold_convert (type, expr);
5052 expr = build_target_expr_with_type (expr, type);
5055 /* Take the address of the thing to which we will bind the
5057 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5058 if (expr == error_mark_node)
5059 return error_mark_node;
5061 /* Convert it to a pointer to the type referred to by the
5062 reference. This will adjust the pointer if a derived to
5063 base conversion is being performed. */
5064 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5066 /* Convert the pointer to the desired reference type. */
5067 return build_nop (ref_type, expr);
5071 return decay_conversion (expr);
5074 /* Warn about deprecated conversion if appropriate. */
5075 string_conv_p (totype, expr, 1);
5080 expr = convert_to_base (expr, totype, !c_cast_p,
5082 return build_nop (totype, expr);
5085 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5092 if (convs->check_narrowing)
5093 check_narrowing (totype, expr);
5095 if (issue_conversion_warnings && (complain & tf_warning))
5096 expr = convert_and_check (totype, expr);
5098 expr = convert (totype, expr);
5103 /* ARG is being passed to a varargs function. Perform any conversions
5104 required. Return the converted value. */
5107 convert_arg_to_ellipsis (tree arg)
5111 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5112 standard conversions are performed. */
5113 arg = decay_conversion (arg);
5116 If the argument has integral or enumeration type that is subject
5117 to the integral promotions (_conv.prom_), or a floating point
5118 type that is subject to the floating point promotion
5119 (_conv.fpprom_), the value of the argument is converted to the
5120 promoted type before the call. */
5121 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5122 && (TYPE_PRECISION (TREE_TYPE (arg))
5123 < TYPE_PRECISION (double_type_node))
5124 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (arg))))
5125 arg = convert_to_real (double_type_node, arg);
5126 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5127 arg = perform_integral_promotions (arg);
5129 arg = require_complete_type (arg);
5131 if (arg != error_mark_node
5132 && (type_has_nontrivial_copy_init (TREE_TYPE (arg))
5133 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (arg))))
5135 /* [expr.call] 5.2.2/7:
5136 Passing a potentially-evaluated argument of class type (Clause 9)
5137 with a non-trivial copy constructor or a non-trivial destructor
5138 with no corresponding parameter is conditionally-supported, with
5139 implementation-defined semantics.
5141 We used to just warn here and do a bitwise copy, but now
5142 cp_expr_size will abort if we try to do that.
5144 If the call appears in the context of a sizeof expression,
5145 it is not potentially-evaluated. */
5146 if (cp_unevaluated_operand == 0)
5147 error ("cannot pass objects of non-trivially-copyable "
5148 "type %q#T through %<...%>", TREE_TYPE (arg));
5154 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5157 build_x_va_arg (tree expr, tree type)
5159 if (processing_template_decl)
5160 return build_min (VA_ARG_EXPR, type, expr);
5162 type = complete_type_or_else (type, NULL_TREE);
5164 if (expr == error_mark_node || !type)
5165 return error_mark_node;
5167 if (type_has_nontrivial_copy_init (type)
5168 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5169 || TREE_CODE (type) == REFERENCE_TYPE)
5171 /* Remove reference types so we don't ICE later on. */
5172 tree type1 = non_reference (type);
5173 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5174 error ("cannot receive objects of non-trivially-copyable type %q#T "
5175 "through %<...%>; ", type);
5176 expr = convert (build_pointer_type (type1), null_node);
5177 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
5181 return build_va_arg (input_location, expr, type);
5184 /* TYPE has been given to va_arg. Apply the default conversions which
5185 would have happened when passed via ellipsis. Return the promoted
5186 type, or the passed type if there is no change. */
5189 cxx_type_promotes_to (tree type)
5193 /* Perform the array-to-pointer and function-to-pointer
5195 type = type_decays_to (type);
5197 promote = type_promotes_to (type);
5198 if (same_type_p (type, promote))
5204 /* ARG is a default argument expression being passed to a parameter of
5205 the indicated TYPE, which is a parameter to FN. Do any required
5206 conversions. Return the converted value. */
5208 static GTY(()) VEC(tree,gc) *default_arg_context;
5211 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5216 /* If the ARG is an unparsed default argument expression, the
5217 conversion cannot be performed. */
5218 if (TREE_CODE (arg) == DEFAULT_ARG)
5220 error ("the default argument for parameter %d of %qD has "
5221 "not yet been parsed",
5223 return error_mark_node;
5226 /* Detect recursion. */
5227 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5230 error ("recursive evaluation of default argument for %q#D", fn);
5231 return error_mark_node;
5233 VEC_safe_push (tree, gc, default_arg_context, fn);
5235 if (fn && DECL_TEMPLATE_INFO (fn))
5236 arg = tsubst_default_argument (fn, type, arg);
5242 The names in the expression are bound, and the semantic
5243 constraints are checked, at the point where the default
5244 expressions appears.
5246 we must not perform access checks here. */
5247 push_deferring_access_checks (dk_no_check);
5248 arg = break_out_target_exprs (arg);
5249 if (TREE_CODE (arg) == CONSTRUCTOR)
5251 arg = digest_init (type, arg);
5252 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5253 "default argument", fn, parmnum,
5254 tf_warning_or_error);
5258 /* We must make a copy of ARG, in case subsequent processing
5259 alters any part of it. For example, during gimplification a
5260 cast of the form (T) &X::f (where "f" is a member function)
5261 will lead to replacing the PTRMEM_CST for &X::f with a
5262 VAR_DECL. We can avoid the copy for constants, since they
5263 are never modified in place. */
5264 if (!CONSTANT_CLASS_P (arg))
5265 arg = unshare_expr (arg);
5266 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5267 "default argument", fn, parmnum,
5268 tf_warning_or_error);
5269 arg = convert_for_arg_passing (type, arg);
5271 pop_deferring_access_checks();
5273 VEC_pop (tree, default_arg_context);
5278 /* Returns the type which will really be used for passing an argument of
5282 type_passed_as (tree type)
5284 /* Pass classes with copy ctors by invisible reference. */
5285 if (TREE_ADDRESSABLE (type))
5287 type = build_reference_type (type);
5288 /* There are no other pointers to this temporary. */
5289 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5291 else if (targetm.calls.promote_prototypes (type)
5292 && INTEGRAL_TYPE_P (type)
5293 && COMPLETE_TYPE_P (type)
5294 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5295 TYPE_SIZE (integer_type_node)))
5296 type = integer_type_node;
5301 /* Actually perform the appropriate conversion. */
5304 convert_for_arg_passing (tree type, tree val)
5308 /* If VAL is a bitfield, then -- since it has already been converted
5309 to TYPE -- it cannot have a precision greater than TYPE.
5311 If it has a smaller precision, we must widen it here. For
5312 example, passing "int f:3;" to a function expecting an "int" will
5313 not result in any conversion before this point.
5315 If the precision is the same we must not risk widening. For
5316 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5317 often have type "int", even though the C++ type for the field is
5318 "long long". If the value is being passed to a function
5319 expecting an "int", then no conversions will be required. But,
5320 if we call convert_bitfield_to_declared_type, the bitfield will
5321 be converted to "long long". */
5322 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5324 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5325 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5327 if (val == error_mark_node)
5329 /* Pass classes with copy ctors by invisible reference. */
5330 else if (TREE_ADDRESSABLE (type))
5331 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5332 else if (targetm.calls.promote_prototypes (type)
5333 && INTEGRAL_TYPE_P (type)
5334 && COMPLETE_TYPE_P (type)
5335 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5336 TYPE_SIZE (integer_type_node)))
5337 val = perform_integral_promotions (val);
5338 if (warn_missing_format_attribute)
5340 tree rhstype = TREE_TYPE (val);
5341 const enum tree_code coder = TREE_CODE (rhstype);
5342 const enum tree_code codel = TREE_CODE (type);
5343 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5345 && check_missing_format_attribute (type, rhstype))
5346 warning (OPT_Wmissing_format_attribute,
5347 "argument of function call might be a candidate for a format attribute");
5352 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5353 which no conversions at all should be done. This is true for some
5354 builtins which don't act like normal functions. */
5357 magic_varargs_p (tree fn)
5359 if (DECL_BUILT_IN (fn))
5360 switch (DECL_FUNCTION_CODE (fn))
5362 case BUILT_IN_CLASSIFY_TYPE:
5363 case BUILT_IN_CONSTANT_P:
5364 case BUILT_IN_NEXT_ARG:
5365 case BUILT_IN_VA_START:
5369 return lookup_attribute ("type generic",
5370 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5376 /* Subroutine of the various build_*_call functions. Overload resolution
5377 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5378 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5379 bitmask of various LOOKUP_* flags which apply to the call itself. */
5382 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5385 const VEC(tree,gc) *args = cand->args;
5386 tree first_arg = cand->first_arg;
5387 conversion **convs = cand->convs;
5389 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5394 unsigned int arg_index = 0;
5398 bool already_used = false;
5400 /* In a template, there is no need to perform all of the work that
5401 is normally done. We are only interested in the type of the call
5402 expression, i.e., the return type of the function. Any semantic
5403 errors will be deferred until the template is instantiated. */
5404 if (processing_template_decl)
5408 const tree *argarray;
5411 return_type = TREE_TYPE (TREE_TYPE (fn));
5412 nargs = VEC_length (tree, args);
5413 if (first_arg == NULL_TREE)
5414 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5422 alcarray = XALLOCAVEC (tree, nargs);
5423 alcarray[0] = first_arg;
5424 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5425 alcarray[ix + 1] = arg;
5426 argarray = alcarray;
5428 expr = build_call_array_loc (input_location,
5429 return_type, build_addr_func (fn), nargs,
5431 if (TREE_THIS_VOLATILE (fn) && cfun)
5432 current_function_returns_abnormally = 1;
5433 if (!VOID_TYPE_P (return_type))
5434 require_complete_type (return_type);
5435 return convert_from_reference (expr);
5438 /* Give any warnings we noticed during overload resolution. */
5441 struct candidate_warning *w;
5442 for (w = cand->warnings; w; w = w->next)
5443 joust (cand, w->loser, 1);
5446 /* Make =delete work with SFINAE. */
5447 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5448 return error_mark_node;
5450 if (DECL_FUNCTION_MEMBER_P (fn))
5452 /* If FN is a template function, two cases must be considered.
5457 template <class T> void f();
5459 template <class T> struct B {
5463 struct C : A, B<int> {
5465 using B<int>::g; // #2
5468 In case #1 where `A::f' is a member template, DECL_ACCESS is
5469 recorded in the primary template but not in its specialization.
5470 We check access of FN using its primary template.
5472 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5473 because it is a member of class template B, DECL_ACCESS is
5474 recorded in the specialization `B<int>::g'. We cannot use its
5475 primary template because `B<T>::g' and `B<int>::g' may have
5476 different access. */
5477 if (DECL_TEMPLATE_INFO (fn)
5478 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5479 perform_or_defer_access_check (cand->access_path,
5480 DECL_TI_TEMPLATE (fn), fn);
5482 perform_or_defer_access_check (cand->access_path, fn, fn);
5485 /* Find maximum size of vector to hold converted arguments. */
5486 parmlen = list_length (parm);
5487 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5488 if (parmlen > nargs)
5490 argarray = (tree *) alloca (nargs * sizeof (tree));
5492 /* The implicit parameters to a constructor are not considered by overload
5493 resolution, and must be of the proper type. */
5494 if (DECL_CONSTRUCTOR_P (fn))
5496 if (first_arg != NULL_TREE)
5498 argarray[j++] = first_arg;
5499 first_arg = NULL_TREE;
5503 argarray[j++] = VEC_index (tree, args, arg_index);
5506 parm = TREE_CHAIN (parm);
5507 /* We should never try to call the abstract constructor. */
5508 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5510 if (DECL_HAS_VTT_PARM_P (fn))
5512 argarray[j++] = VEC_index (tree, args, arg_index);
5514 parm = TREE_CHAIN (parm);
5517 /* Bypass access control for 'this' parameter. */
5518 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5520 tree parmtype = TREE_VALUE (parm);
5521 tree arg = (first_arg != NULL_TREE
5523 : VEC_index (tree, args, arg_index));
5524 tree argtype = TREE_TYPE (arg);
5528 if (convs[i]->bad_p)
5530 if (complain & tf_error)
5531 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5532 TREE_TYPE (argtype), fn);
5534 return error_mark_node;
5537 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5538 X is called for an object that is not of type X, or of a type
5539 derived from X, the behavior is undefined.
5541 So we can assume that anything passed as 'this' is non-null, and
5542 optimize accordingly. */
5543 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5544 /* Convert to the base in which the function was declared. */
5545 gcc_assert (cand->conversion_path != NULL_TREE);
5546 converted_arg = build_base_path (PLUS_EXPR,
5548 cand->conversion_path,
5550 /* Check that the base class is accessible. */
5551 if (!accessible_base_p (TREE_TYPE (argtype),
5552 BINFO_TYPE (cand->conversion_path), true))
5553 error ("%qT is not an accessible base of %qT",
5554 BINFO_TYPE (cand->conversion_path),
5555 TREE_TYPE (argtype));
5556 /* If fn was found by a using declaration, the conversion path
5557 will be to the derived class, not the base declaring fn. We
5558 must convert from derived to base. */
5559 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5560 TREE_TYPE (parmtype), ba_unique, NULL);
5561 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5564 argarray[j++] = converted_arg;
5565 parm = TREE_CHAIN (parm);
5566 if (first_arg != NULL_TREE)
5567 first_arg = NULL_TREE;
5574 gcc_assert (first_arg == NULL_TREE);
5575 for (; arg_index < VEC_length (tree, args) && parm;
5576 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5578 tree type = TREE_VALUE (parm);
5582 /* Don't make a copy here if build_call is going to. */
5583 if (conv->kind == ck_rvalue
5584 && COMPLETE_TYPE_P (complete_type (type))
5585 && !TREE_ADDRESSABLE (type))
5586 conv = conv->u.next;
5588 /* Warn about initializer_list deduction that isn't currently in the
5590 if (cxx_dialect > cxx98
5591 && flag_deduce_init_list
5592 && cand->template_decl
5593 && is_std_init_list (non_reference (type)))
5595 tree tmpl = TI_TEMPLATE (cand->template_decl);
5596 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
5597 tree patparm = get_pattern_parm (realparm, tmpl);
5599 if (!is_std_init_list (non_reference (TREE_TYPE (patparm))))
5601 pedwarn (input_location, 0, "deducing %qT as %qT",
5602 non_reference (TREE_TYPE (patparm)),
5603 non_reference (type));
5604 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
5605 pedwarn (input_location, 0,
5606 " (you can disable this with -fno-deduce-init-list)");
5610 val = convert_like_with_context
5611 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5614 val = convert_for_arg_passing (type, val);
5615 if (val == error_mark_node)
5616 return error_mark_node;
5618 argarray[j++] = val;
5621 /* Default arguments */
5622 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5623 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5624 TREE_PURPOSE (parm),
5627 for (; arg_index < VEC_length (tree, args); ++arg_index)
5629 tree a = VEC_index (tree, args, arg_index);
5630 if (magic_varargs_p (fn))
5631 /* Do no conversions for magic varargs. */;
5633 a = convert_arg_to_ellipsis (a);
5637 gcc_assert (j <= nargs);
5640 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5641 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5643 /* Avoid actually calling copy constructors and copy assignment operators,
5646 if (! flag_elide_constructors)
5647 /* Do things the hard way. */;
5648 else if (cand->num_convs == 1
5649 && (DECL_COPY_CONSTRUCTOR_P (fn)
5650 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5653 tree arg = argarray[num_artificial_parms_for (fn)];
5656 /* Pull out the real argument, disregarding const-correctness. */
5658 while (CONVERT_EXPR_P (targ)
5659 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5660 targ = TREE_OPERAND (targ, 0);
5661 if (TREE_CODE (targ) == ADDR_EXPR)
5663 targ = TREE_OPERAND (targ, 0);
5664 if (!same_type_ignoring_top_level_qualifiers_p
5665 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5674 arg = cp_build_indirect_ref (arg, 0, complain);
5676 if (TREE_CODE (arg) == TARGET_EXPR
5677 && TARGET_EXPR_LIST_INIT_P (arg))
5679 /* Copy-list-initialization doesn't require the copy constructor
5682 /* [class.copy]: the copy constructor is implicitly defined even if
5683 the implementation elided its use. */
5684 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5687 already_used = true;
5690 /* If we're creating a temp and we already have one, don't create a
5691 new one. If we're not creating a temp but we get one, use
5692 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5693 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5694 temp or an INIT_EXPR otherwise. */
5695 fa = (cand->first_arg != NULL_TREE
5697 : VEC_index (tree, args, 0));
5698 if (integer_zerop (fa))
5700 if (TREE_CODE (arg) == TARGET_EXPR)
5702 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5703 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5705 else if (TREE_CODE (arg) == TARGET_EXPR
5706 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5707 && !move_fn_p (fn)))
5709 tree to = stabilize_reference (cp_build_indirect_ref (fa, 0,
5712 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5716 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5718 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5720 tree to = stabilize_reference
5721 (cp_build_indirect_ref (argarray[0], 0, complain));
5722 tree type = TREE_TYPE (to);
5723 tree as_base = CLASSTYPE_AS_BASE (type);
5724 tree arg = argarray[1];
5726 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5728 arg = cp_build_indirect_ref (arg, 0, complain);
5729 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5733 /* We must only copy the non-tail padding parts.
5734 Use __builtin_memcpy for the bitwise copy.
5735 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5736 instead of an explicit call to memcpy. */
5738 tree arg0, arg1, arg2, t;
5739 tree test = NULL_TREE;
5741 arg2 = TYPE_SIZE_UNIT (as_base);
5743 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5745 if (!can_trust_pointer_alignment ())
5747 /* If we can't be sure about pointer alignment, a call
5748 to __builtin_memcpy is expanded as a call to memcpy, which
5749 is invalid with identical args. Otherwise it is
5750 expanded as a block move, which should be safe. */
5751 arg0 = save_expr (arg0);
5752 arg1 = save_expr (arg1);
5753 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5755 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5756 t = build_call_n (t, 3, arg0, arg1, arg2);
5758 t = convert (TREE_TYPE (arg0), t);
5760 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5761 val = cp_build_indirect_ref (t, 0, complain);
5762 TREE_NO_WARNING (val) = 1;
5771 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5774 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5777 gcc_assert (binfo && binfo != error_mark_node);
5779 /* Warn about deprecated virtual functions now, since we're about
5780 to throw away the decl. */
5781 if (TREE_DEPRECATED (fn))
5782 warn_deprecated_use (fn, NULL_TREE);
5784 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5785 if (TREE_SIDE_EFFECTS (argarray[0]))
5786 argarray[0] = save_expr (argarray[0]);
5787 t = build_pointer_type (TREE_TYPE (fn));
5788 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5789 fn = build_java_interface_fn_ref (fn, argarray[0]);
5791 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5795 fn = build_addr_func (fn);
5797 return build_cxx_call (fn, nargs, argarray);
5800 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5801 This function performs no overload resolution, conversion, or other
5802 high-level operations. */
5805 build_cxx_call (tree fn, int nargs, tree *argarray)
5809 fn = build_call_a (fn, nargs, argarray);
5811 /* If this call might throw an exception, note that fact. */
5812 fndecl = get_callee_fndecl (fn);
5813 if ((!fndecl || !TREE_NOTHROW (fndecl))
5814 && at_function_scope_p ()
5816 cp_function_chain->can_throw = 1;
5818 /* Check that arguments to builtin functions match the expectations. */
5820 && DECL_BUILT_IN (fndecl)
5821 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5822 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5823 return error_mark_node;
5825 /* Some built-in function calls will be evaluated at compile-time in
5827 fn = fold_if_not_in_template (fn);
5829 if (VOID_TYPE_P (TREE_TYPE (fn)))
5832 fn = require_complete_type (fn);
5833 if (fn == error_mark_node)
5834 return error_mark_node;
5836 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5837 fn = build_cplus_new (TREE_TYPE (fn), fn);
5838 return convert_from_reference (fn);
5841 static GTY(()) tree java_iface_lookup_fn;
5843 /* Make an expression which yields the address of the Java interface
5844 method FN. This is achieved by generating a call to libjava's
5845 _Jv_LookupInterfaceMethodIdx(). */
5848 build_java_interface_fn_ref (tree fn, tree instance)
5850 tree lookup_fn, method, idx;
5851 tree klass_ref, iface, iface_ref;
5854 if (!java_iface_lookup_fn)
5856 tree endlink = build_void_list_node ();
5857 tree t = tree_cons (NULL_TREE, ptr_type_node,
5858 tree_cons (NULL_TREE, ptr_type_node,
5859 tree_cons (NULL_TREE, java_int_type_node,
5861 java_iface_lookup_fn
5862 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5863 build_function_type (ptr_type_node, t),
5864 0, NOT_BUILT_IN, NULL, NULL_TREE);
5867 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5868 This is the first entry in the vtable. */
5869 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5870 tf_warning_or_error),
5873 /* Get the java.lang.Class pointer for the interface being called. */
5874 iface = DECL_CONTEXT (fn);
5875 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5876 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5877 || DECL_CONTEXT (iface_ref) != iface)
5879 error ("could not find class$ field in java interface type %qT",
5881 return error_mark_node;
5883 iface_ref = build_address (iface_ref);
5884 iface_ref = convert (build_pointer_type (iface), iface_ref);
5886 /* Determine the itable index of FN. */
5888 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5890 if (!DECL_VIRTUAL_P (method))
5896 idx = build_int_cst (NULL_TREE, i);
5898 lookup_fn = build1 (ADDR_EXPR,
5899 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5900 java_iface_lookup_fn);
5901 return build_call_nary (ptr_type_node, lookup_fn,
5902 3, klass_ref, iface_ref, idx);
5905 /* Returns the value to use for the in-charge parameter when making a
5906 call to a function with the indicated NAME.
5908 FIXME:Can't we find a neater way to do this mapping? */
5911 in_charge_arg_for_name (tree name)
5913 if (name == base_ctor_identifier
5914 || name == base_dtor_identifier)
5915 return integer_zero_node;
5916 else if (name == complete_ctor_identifier)
5917 return integer_one_node;
5918 else if (name == complete_dtor_identifier)
5919 return integer_two_node;
5920 else if (name == deleting_dtor_identifier)
5921 return integer_three_node;
5923 /* This function should only be called with one of the names listed
5929 /* Build a call to a constructor, destructor, or an assignment
5930 operator for INSTANCE, an expression with class type. NAME
5931 indicates the special member function to call; *ARGS are the
5932 arguments. ARGS may be NULL. This may change ARGS. BINFO
5933 indicates the base of INSTANCE that is to be passed as the `this'
5934 parameter to the member function called.
5936 FLAGS are the LOOKUP_* flags to use when processing the call.
5938 If NAME indicates a complete object constructor, INSTANCE may be
5939 NULL_TREE. In this case, the caller will call build_cplus_new to
5940 store the newly constructed object into a VAR_DECL. */
5943 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
5944 tree binfo, int flags, tsubst_flags_t complain)
5947 /* The type of the subobject to be constructed or destroyed. */
5949 VEC(tree,gc) *allocated = NULL;
5952 gcc_assert (name == complete_ctor_identifier
5953 || name == base_ctor_identifier
5954 || name == complete_dtor_identifier
5955 || name == base_dtor_identifier
5956 || name == deleting_dtor_identifier
5957 || name == ansi_assopname (NOP_EXPR));
5960 /* Resolve the name. */
5961 if (!complete_type_or_else (binfo, NULL_TREE))
5962 return error_mark_node;
5964 binfo = TYPE_BINFO (binfo);
5967 gcc_assert (binfo != NULL_TREE);
5969 class_type = BINFO_TYPE (binfo);
5971 /* Handle the special case where INSTANCE is NULL_TREE. */
5972 if (name == complete_ctor_identifier && !instance)
5974 instance = build_int_cst (build_pointer_type (class_type), 0);
5975 instance = build1 (INDIRECT_REF, class_type, instance);
5979 if (name == complete_dtor_identifier
5980 || name == base_dtor_identifier
5981 || name == deleting_dtor_identifier)
5982 gcc_assert (args == NULL || VEC_empty (tree, *args));
5984 /* Convert to the base class, if necessary. */
5985 if (!same_type_ignoring_top_level_qualifiers_p
5986 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5988 if (name != ansi_assopname (NOP_EXPR))
5989 /* For constructors and destructors, either the base is
5990 non-virtual, or it is virtual but we are doing the
5991 conversion from a constructor or destructor for the
5992 complete object. In either case, we can convert
5994 instance = convert_to_base_statically (instance, binfo);
5996 /* However, for assignment operators, we must convert
5997 dynamically if the base is virtual. */
5998 instance = build_base_path (PLUS_EXPR, instance,
5999 binfo, /*nonnull=*/1);
6003 gcc_assert (instance != NULL_TREE);
6005 fns = lookup_fnfields (binfo, name, 1);
6007 /* When making a call to a constructor or destructor for a subobject
6008 that uses virtual base classes, pass down a pointer to a VTT for
6010 if ((name == base_ctor_identifier
6011 || name == base_dtor_identifier)
6012 && CLASSTYPE_VBASECLASSES (class_type))
6017 /* If the current function is a complete object constructor
6018 or destructor, then we fetch the VTT directly.
6019 Otherwise, we look it up using the VTT we were given. */
6020 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6021 vtt = decay_conversion (vtt);
6022 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6023 build2 (EQ_EXPR, boolean_type_node,
6024 current_in_charge_parm, integer_zero_node),
6027 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6028 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6029 BINFO_SUBVTT_INDEX (binfo));
6033 allocated = make_tree_vector ();
6037 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6040 ret = build_new_method_call (instance, fns, args,
6041 TYPE_BINFO (BINFO_TYPE (binfo)),
6045 if (allocated != NULL)
6046 release_tree_vector (allocated);
6051 /* Return the NAME, as a C string. The NAME indicates a function that
6052 is a member of TYPE. *FREE_P is set to true if the caller must
6053 free the memory returned.
6055 Rather than go through all of this, we should simply set the names
6056 of constructors and destructors appropriately, and dispense with
6057 ctor_identifier, dtor_identifier, etc. */
6060 name_as_c_string (tree name, tree type, bool *free_p)
6064 /* Assume that we will not allocate memory. */
6066 /* Constructors and destructors are special. */
6067 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6070 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6071 /* For a destructor, add the '~'. */
6072 if (name == complete_dtor_identifier
6073 || name == base_dtor_identifier
6074 || name == deleting_dtor_identifier)
6076 pretty_name = concat ("~", pretty_name, NULL);
6077 /* Remember that we need to free the memory allocated. */
6081 else if (IDENTIFIER_TYPENAME_P (name))
6083 pretty_name = concat ("operator ",
6084 type_as_string_translate (TREE_TYPE (name),
6085 TFF_PLAIN_IDENTIFIER),
6087 /* Remember that we need to free the memory allocated. */
6091 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6096 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6097 be set, upon return, to the function called. ARGS may be NULL.
6098 This may change ARGS. */
6101 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6102 tree conversion_path, int flags,
6103 tree *fn_p, tsubst_flags_t complain)
6105 struct z_candidate *candidates = 0, *cand;
6106 tree explicit_targs = NULL_TREE;
6107 tree basetype = NULL_TREE;
6110 tree first_mem_arg = NULL_TREE;
6113 bool skip_first_for_error;
6114 VEC(tree,gc) *user_args;
6118 int template_only = 0;
6122 VEC(tree,gc) *orig_args = NULL;
6125 gcc_assert (instance != NULL_TREE);
6127 /* We don't know what function we're going to call, yet. */
6131 if (error_operand_p (instance)
6132 || error_operand_p (fns))
6133 return error_mark_node;
6135 if (!BASELINK_P (fns))
6137 if (complain & tf_error)
6138 error ("call to non-function %qD", fns);
6139 return error_mark_node;
6142 orig_instance = instance;
6145 /* Dismantle the baselink to collect all the information we need. */
6146 if (!conversion_path)
6147 conversion_path = BASELINK_BINFO (fns);
6148 access_binfo = BASELINK_ACCESS_BINFO (fns);
6149 optype = BASELINK_OPTYPE (fns);
6150 fns = BASELINK_FUNCTIONS (fns);
6151 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6153 explicit_targs = TREE_OPERAND (fns, 1);
6154 fns = TREE_OPERAND (fns, 0);
6157 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6158 || TREE_CODE (fns) == TEMPLATE_DECL
6159 || TREE_CODE (fns) == OVERLOAD);
6160 fn = get_first_fn (fns);
6161 name = DECL_NAME (fn);
6163 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6164 gcc_assert (CLASS_TYPE_P (basetype));
6166 if (processing_template_decl)
6168 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6169 instance = build_non_dependent_expr (instance);
6171 make_args_non_dependent (*args);
6174 /* Figure out whether to skip the first argument for the error
6175 message we will display to users if an error occurs. We don't
6176 want to display any compiler-generated arguments. The "this"
6177 pointer hasn't been added yet. However, we must remove the VTT
6178 pointer if this is a call to a base-class constructor or
6180 skip_first_for_error = false;
6181 user_args = args == NULL ? NULL : *args;
6182 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6184 /* Callers should explicitly indicate whether they want to construct
6185 the complete object or just the part without virtual bases. */
6186 gcc_assert (name != ctor_identifier);
6187 /* Similarly for destructors. */
6188 gcc_assert (name != dtor_identifier);
6189 /* Remove the VTT pointer, if present. */
6190 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6191 && CLASSTYPE_VBASECLASSES (basetype))
6192 skip_first_for_error = true;
6195 /* Process the argument list. */
6196 if (args != NULL && *args != NULL)
6198 *args = resolve_args (*args);
6200 return error_mark_node;
6203 instance_ptr = build_this (instance);
6205 /* It's OK to call destructors and constructors on cv-qualified objects.
6206 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6208 if (DECL_DESTRUCTOR_P (fn)
6209 || DECL_CONSTRUCTOR_P (fn))
6211 tree type = build_pointer_type (basetype);
6212 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6213 instance_ptr = build_nop (type, instance_ptr);
6215 if (DECL_DESTRUCTOR_P (fn))
6216 name = complete_dtor_identifier;
6218 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6219 initializer, not T({ }). If the type doesn't have a list ctor,
6220 break apart the list into separate ctor args. */
6221 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6222 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6223 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6224 && !TYPE_HAS_LIST_CTOR (basetype))
6226 gcc_assert (VEC_length (tree, *args) == 1);
6227 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6230 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6231 first_mem_arg = instance_ptr;
6233 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6234 p = conversion_obstack_alloc (0);
6236 for (fn = fns; fn; fn = OVL_NEXT (fn))
6238 tree t = OVL_CURRENT (fn);
6239 tree this_first_arg;
6241 /* We can end up here for copy-init of same or base class. */
6242 if ((flags & LOOKUP_ONLYCONVERTING)
6243 && DECL_NONCONVERTING_P (t))
6246 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6247 this_first_arg = first_mem_arg;
6249 this_first_arg = NULL_TREE;
6251 if (TREE_CODE (t) == TEMPLATE_DECL)
6252 /* A member template. */
6253 add_template_candidate (&candidates, t,
6257 args == NULL ? NULL : *args,
6263 else if (! template_only)
6264 add_function_candidate (&candidates, t,
6267 args == NULL ? NULL : *args,
6273 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6276 if (complain & tf_error)
6278 if (!COMPLETE_TYPE_P (basetype))
6279 cxx_incomplete_type_error (instance_ptr, basetype);
6286 pretty_name = name_as_c_string (name, basetype, &free_p);
6287 arglist = build_tree_list_vec (user_args);
6288 if (skip_first_for_error)
6289 arglist = TREE_CHAIN (arglist);
6290 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6291 basetype, pretty_name, arglist,
6292 TREE_TYPE (TREE_TYPE (instance_ptr)));
6296 print_z_candidates (candidates);
6298 call = error_mark_node;
6302 cand = tourney (candidates);
6309 if (complain & tf_error)
6311 pretty_name = name_as_c_string (name, basetype, &free_p);
6312 arglist = build_tree_list_vec (user_args);
6313 if (skip_first_for_error)
6314 arglist = TREE_CHAIN (arglist);
6315 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6317 print_z_candidates (candidates);
6321 call = error_mark_node;
6327 if (!(flags & LOOKUP_NONVIRTUAL)
6328 && DECL_PURE_VIRTUAL_P (fn)
6329 && instance == current_class_ref
6330 && (DECL_CONSTRUCTOR_P (current_function_decl)
6331 || DECL_DESTRUCTOR_P (current_function_decl))
6332 && (complain & tf_warning))
6333 /* This is not an error, it is runtime undefined
6335 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6336 "abstract virtual %q#D called from constructor"
6337 : "abstract virtual %q#D called from destructor"),
6340 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6341 && is_dummy_object (instance_ptr))
6343 if (complain & tf_error)
6344 error ("cannot call member function %qD without object",
6346 call = error_mark_node;
6350 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6351 && resolves_to_fixed_type_p (instance, 0))
6352 flags |= LOOKUP_NONVIRTUAL;
6353 /* Now we know what function is being called. */
6356 /* Build the actual CALL_EXPR. */
6357 call = build_over_call (cand, flags, complain);
6358 /* In an expression of the form `a->f()' where `f' turns
6359 out to be a static member function, `a' is
6360 none-the-less evaluated. */
6361 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6362 && !is_dummy_object (instance_ptr)
6363 && TREE_SIDE_EFFECTS (instance_ptr))
6364 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6365 instance_ptr, call);
6366 else if (call != error_mark_node
6367 && DECL_DESTRUCTOR_P (cand->fn)
6368 && !VOID_TYPE_P (TREE_TYPE (call)))
6369 /* An explicit call of the form "x->~X()" has type
6370 "void". However, on platforms where destructors
6371 return "this" (i.e., those where
6372 targetm.cxx.cdtor_returns_this is true), such calls
6373 will appear to have a return value of pointer type
6374 to the low-level call machinery. We do not want to
6375 change the low-level machinery, since we want to be
6376 able to optimize "delete f()" on such platforms as
6377 "operator delete(~X(f()))" (rather than generating
6378 "t = f(), ~X(t), operator delete (t)"). */
6379 call = build_nop (void_type_node, call);
6384 if (processing_template_decl && call != error_mark_node)
6386 bool cast_to_void = false;
6388 if (TREE_CODE (call) == COMPOUND_EXPR)
6389 call = TREE_OPERAND (call, 1);
6390 else if (TREE_CODE (call) == NOP_EXPR)
6392 cast_to_void = true;
6393 call = TREE_OPERAND (call, 0);
6395 if (TREE_CODE (call) == INDIRECT_REF)
6396 call = TREE_OPERAND (call, 0);
6397 call = (build_min_non_dep_call_vec
6399 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6400 orig_instance, orig_fns, NULL_TREE),
6402 call = convert_from_reference (call);
6404 call = build_nop (void_type_node, call);
6407 /* Free all the conversions we allocated. */
6408 obstack_free (&conversion_obstack, p);
6410 if (orig_args != NULL)
6411 release_tree_vector (orig_args);
6416 /* Returns true iff standard conversion sequence ICS1 is a proper
6417 subsequence of ICS2. */
6420 is_subseq (conversion *ics1, conversion *ics2)
6422 /* We can assume that a conversion of the same code
6423 between the same types indicates a subsequence since we only get
6424 here if the types we are converting from are the same. */
6426 while (ics1->kind == ck_rvalue
6427 || ics1->kind == ck_lvalue)
6428 ics1 = ics1->u.next;
6432 while (ics2->kind == ck_rvalue
6433 || ics2->kind == ck_lvalue)
6434 ics2 = ics2->u.next;
6436 if (ics2->kind == ck_user
6437 || ics2->kind == ck_ambig
6438 || ics2->kind == ck_identity)
6439 /* At this point, ICS1 cannot be a proper subsequence of
6440 ICS2. We can get a USER_CONV when we are comparing the
6441 second standard conversion sequence of two user conversion
6445 ics2 = ics2->u.next;
6447 if (ics2->kind == ics1->kind
6448 && same_type_p (ics2->type, ics1->type)
6449 && same_type_p (ics2->u.next->type,
6450 ics1->u.next->type))
6455 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6456 be any _TYPE nodes. */
6459 is_properly_derived_from (tree derived, tree base)
6461 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6464 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6465 considers every class derived from itself. */
6466 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6467 && DERIVED_FROM_P (base, derived));
6470 /* We build the ICS for an implicit object parameter as a pointer
6471 conversion sequence. However, such a sequence should be compared
6472 as if it were a reference conversion sequence. If ICS is the
6473 implicit conversion sequence for an implicit object parameter,
6474 modify it accordingly. */
6477 maybe_handle_implicit_object (conversion **ics)
6481 /* [over.match.funcs]
6483 For non-static member functions, the type of the
6484 implicit object parameter is "reference to cv X"
6485 where X is the class of which the function is a
6486 member and cv is the cv-qualification on the member
6487 function declaration. */
6488 conversion *t = *ics;
6489 tree reference_type;
6491 /* The `this' parameter is a pointer to a class type. Make the
6492 implicit conversion talk about a reference to that same class
6494 reference_type = TREE_TYPE (t->type);
6495 reference_type = build_reference_type (reference_type);
6497 if (t->kind == ck_qual)
6499 if (t->kind == ck_ptr)
6501 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6502 t = direct_reference_binding (reference_type, t);
6504 t->rvaluedness_matches_p = 0;
6509 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6510 and return the initial reference binding conversion. Otherwise,
6511 leave *ICS unchanged and return NULL. */
6514 maybe_handle_ref_bind (conversion **ics)
6516 if ((*ics)->kind == ck_ref_bind)
6518 conversion *old_ics = *ics;
6519 *ics = old_ics->u.next;
6520 (*ics)->user_conv_p = old_ics->user_conv_p;
6527 /* Compare two implicit conversion sequences according to the rules set out in
6528 [over.ics.rank]. Return values:
6530 1: ics1 is better than ics2
6531 -1: ics2 is better than ics1
6532 0: ics1 and ics2 are indistinguishable */
6535 compare_ics (conversion *ics1, conversion *ics2)
6541 tree deref_from_type1 = NULL_TREE;
6542 tree deref_from_type2 = NULL_TREE;
6543 tree deref_to_type1 = NULL_TREE;
6544 tree deref_to_type2 = NULL_TREE;
6545 conversion_rank rank1, rank2;
6547 /* REF_BINDING is nonzero if the result of the conversion sequence
6548 is a reference type. In that case REF_CONV is the reference
6549 binding conversion. */
6550 conversion *ref_conv1;
6551 conversion *ref_conv2;
6553 /* Handle implicit object parameters. */
6554 maybe_handle_implicit_object (&ics1);
6555 maybe_handle_implicit_object (&ics2);
6557 /* Handle reference parameters. */
6558 ref_conv1 = maybe_handle_ref_bind (&ics1);
6559 ref_conv2 = maybe_handle_ref_bind (&ics2);
6561 /* List-initialization sequence L1 is a better conversion sequence than
6562 list-initialization sequence L2 if L1 converts to
6563 std::initializer_list<X> for some X and L2 does not. */
6564 if (ics1->kind == ck_list && ics2->kind != ck_list)
6566 if (ics2->kind == ck_list && ics1->kind != ck_list)
6571 When comparing the basic forms of implicit conversion sequences (as
6572 defined in _over.best.ics_)
6574 --a standard conversion sequence (_over.ics.scs_) is a better
6575 conversion sequence than a user-defined conversion sequence
6576 or an ellipsis conversion sequence, and
6578 --a user-defined conversion sequence (_over.ics.user_) is a
6579 better conversion sequence than an ellipsis conversion sequence
6580 (_over.ics.ellipsis_). */
6581 rank1 = CONVERSION_RANK (ics1);
6582 rank2 = CONVERSION_RANK (ics2);
6586 else if (rank1 < rank2)
6589 if (rank1 == cr_bad)
6591 /* XXX Isn't this an extension? */
6592 /* Both ICS are bad. We try to make a decision based on what
6593 would have happened if they'd been good. */
6594 if (ics1->user_conv_p > ics2->user_conv_p
6595 || ics1->rank > ics2->rank)
6597 else if (ics1->user_conv_p < ics2->user_conv_p
6598 || ics1->rank < ics2->rank)
6601 /* We couldn't make up our minds; try to figure it out below. */
6604 if (ics1->ellipsis_p)
6605 /* Both conversions are ellipsis conversions. */
6608 /* User-defined conversion sequence U1 is a better conversion sequence
6609 than another user-defined conversion sequence U2 if they contain the
6610 same user-defined conversion operator or constructor and if the sec-
6611 ond standard conversion sequence of U1 is better than the second
6612 standard conversion sequence of U2. */
6614 if (ics1->user_conv_p)
6619 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6620 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6622 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6623 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6626 if (t1->cand->fn != t2->cand->fn)
6629 /* We can just fall through here, after setting up
6630 FROM_TYPE1 and FROM_TYPE2. */
6631 from_type1 = t1->type;
6632 from_type2 = t2->type;
6639 /* We're dealing with two standard conversion sequences.
6643 Standard conversion sequence S1 is a better conversion
6644 sequence than standard conversion sequence S2 if
6646 --S1 is a proper subsequence of S2 (comparing the conversion
6647 sequences in the canonical form defined by _over.ics.scs_,
6648 excluding any Lvalue Transformation; the identity
6649 conversion sequence is considered to be a subsequence of
6650 any non-identity conversion sequence */
6653 while (t1->kind != ck_identity)
6655 from_type1 = t1->type;
6658 while (t2->kind != ck_identity)
6660 from_type2 = t2->type;
6663 /* One sequence can only be a subsequence of the other if they start with
6664 the same type. They can start with different types when comparing the
6665 second standard conversion sequence in two user-defined conversion
6667 if (same_type_p (from_type1, from_type2))
6669 if (is_subseq (ics1, ics2))
6671 if (is_subseq (ics2, ics1))
6679 --the rank of S1 is better than the rank of S2 (by the rules
6682 Standard conversion sequences are ordered by their ranks: an Exact
6683 Match is a better conversion than a Promotion, which is a better
6684 conversion than a Conversion.
6686 Two conversion sequences with the same rank are indistinguishable
6687 unless one of the following rules applies:
6689 --A conversion that is not a conversion of a pointer, or pointer
6690 to member, to bool is better than another conversion that is such
6693 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6694 so that we do not have to check it explicitly. */
6695 if (ics1->rank < ics2->rank)
6697 else if (ics2->rank < ics1->rank)
6700 to_type1 = ics1->type;
6701 to_type2 = ics2->type;
6703 /* A conversion from scalar arithmetic type to complex is worse than a
6704 conversion between scalar arithmetic types. */
6705 if (same_type_p (from_type1, from_type2)
6706 && ARITHMETIC_TYPE_P (from_type1)
6707 && ARITHMETIC_TYPE_P (to_type1)
6708 && ARITHMETIC_TYPE_P (to_type2)
6709 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6710 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6712 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6718 if (TYPE_PTR_P (from_type1)
6719 && TYPE_PTR_P (from_type2)
6720 && TYPE_PTR_P (to_type1)
6721 && TYPE_PTR_P (to_type2))
6723 deref_from_type1 = TREE_TYPE (from_type1);
6724 deref_from_type2 = TREE_TYPE (from_type2);
6725 deref_to_type1 = TREE_TYPE (to_type1);
6726 deref_to_type2 = TREE_TYPE (to_type2);
6728 /* The rules for pointers to members A::* are just like the rules
6729 for pointers A*, except opposite: if B is derived from A then
6730 A::* converts to B::*, not vice versa. For that reason, we
6731 switch the from_ and to_ variables here. */
6732 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6733 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6734 || (TYPE_PTRMEMFUNC_P (from_type1)
6735 && TYPE_PTRMEMFUNC_P (from_type2)
6736 && TYPE_PTRMEMFUNC_P (to_type1)
6737 && TYPE_PTRMEMFUNC_P (to_type2)))
6739 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6740 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6741 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6742 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6745 if (deref_from_type1 != NULL_TREE
6746 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6747 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6749 /* This was one of the pointer or pointer-like conversions.
6753 --If class B is derived directly or indirectly from class A,
6754 conversion of B* to A* is better than conversion of B* to
6755 void*, and conversion of A* to void* is better than
6756 conversion of B* to void*. */
6757 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6758 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6760 if (is_properly_derived_from (deref_from_type1,
6763 else if (is_properly_derived_from (deref_from_type2,
6767 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6768 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6770 if (same_type_p (deref_from_type1, deref_from_type2))
6772 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6774 if (is_properly_derived_from (deref_from_type1,
6778 /* We know that DEREF_TO_TYPE1 is `void' here. */
6779 else if (is_properly_derived_from (deref_from_type1,
6784 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6785 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6789 --If class B is derived directly or indirectly from class A
6790 and class C is derived directly or indirectly from B,
6792 --conversion of C* to B* is better than conversion of C* to
6795 --conversion of B* to A* is better than conversion of C* to
6797 if (same_type_p (deref_from_type1, deref_from_type2))
6799 if (is_properly_derived_from (deref_to_type1,
6802 else if (is_properly_derived_from (deref_to_type2,
6806 else if (same_type_p (deref_to_type1, deref_to_type2))
6808 if (is_properly_derived_from (deref_from_type2,
6811 else if (is_properly_derived_from (deref_from_type1,
6817 else if (CLASS_TYPE_P (non_reference (from_type1))
6818 && same_type_p (from_type1, from_type2))
6820 tree from = non_reference (from_type1);
6824 --binding of an expression of type C to a reference of type
6825 B& is better than binding an expression of type C to a
6826 reference of type A&
6828 --conversion of C to B is better than conversion of C to A, */
6829 if (is_properly_derived_from (from, to_type1)
6830 && is_properly_derived_from (from, to_type2))
6832 if (is_properly_derived_from (to_type1, to_type2))
6834 else if (is_properly_derived_from (to_type2, to_type1))
6838 else if (CLASS_TYPE_P (non_reference (to_type1))
6839 && same_type_p (to_type1, to_type2))
6841 tree to = non_reference (to_type1);
6845 --binding of an expression of type B to a reference of type
6846 A& is better than binding an expression of type C to a
6847 reference of type A&,
6849 --conversion of B to A is better than conversion of C to A */
6850 if (is_properly_derived_from (from_type1, to)
6851 && is_properly_derived_from (from_type2, to))
6853 if (is_properly_derived_from (from_type2, from_type1))
6855 else if (is_properly_derived_from (from_type1, from_type2))
6862 --S1 and S2 differ only in their qualification conversion and yield
6863 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6864 qualification signature of type T1 is a proper subset of the cv-
6865 qualification signature of type T2 */
6866 if (ics1->kind == ck_qual
6867 && ics2->kind == ck_qual
6868 && same_type_p (from_type1, from_type2))
6870 int result = comp_cv_qual_signature (to_type1, to_type2);
6877 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6878 to an implicit object parameter, and either S1 binds an lvalue reference
6879 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6880 reference to an rvalue and S2 binds an lvalue reference
6881 (C++0x draft standard, 13.3.3.2)
6883 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6884 types to which the references refer are the same type except for
6885 top-level cv-qualifiers, and the type to which the reference
6886 initialized by S2 refers is more cv-qualified than the type to
6887 which the reference initialized by S1 refers */
6889 if (ref_conv1 && ref_conv2)
6891 if (!ref_conv1->this_p && !ref_conv2->this_p
6892 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6893 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6895 if (ref_conv1->rvaluedness_matches_p)
6897 if (ref_conv2->rvaluedness_matches_p)
6901 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6902 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6903 TREE_TYPE (ref_conv1->type));
6906 /* Neither conversion sequence is better than the other. */
6910 /* The source type for this standard conversion sequence. */
6913 source_type (conversion *t)
6915 for (;; t = t->u.next)
6917 if (t->kind == ck_user
6918 || t->kind == ck_ambig
6919 || t->kind == ck_identity)
6925 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6926 a pointer to LOSER and re-running joust to produce the warning if WINNER
6927 is actually used. */
6930 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6932 candidate_warning *cw = (candidate_warning *)
6933 conversion_obstack_alloc (sizeof (candidate_warning));
6935 cw->next = winner->warnings;
6936 winner->warnings = cw;
6939 /* Compare two candidates for overloading as described in
6940 [over.match.best]. Return values:
6942 1: cand1 is better than cand2
6943 -1: cand2 is better than cand1
6944 0: cand1 and cand2 are indistinguishable */
6947 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6950 int off1 = 0, off2 = 0;
6954 /* Candidates that involve bad conversions are always worse than those
6956 if (cand1->viable > cand2->viable)
6958 if (cand1->viable < cand2->viable)
6961 /* If we have two pseudo-candidates for conversions to the same type,
6962 or two candidates for the same function, arbitrarily pick one. */
6963 if (cand1->fn == cand2->fn
6964 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6967 /* a viable function F1
6968 is defined to be a better function than another viable function F2 if
6969 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6970 ICSi(F2), and then */
6972 /* for some argument j, ICSj(F1) is a better conversion sequence than
6975 /* For comparing static and non-static member functions, we ignore
6976 the implicit object parameter of the non-static function. The
6977 standard says to pretend that the static function has an object
6978 parm, but that won't work with operator overloading. */
6979 len = cand1->num_convs;
6980 if (len != cand2->num_convs)
6982 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6983 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6985 gcc_assert (static_1 != static_2);
6996 for (i = 0; i < len; ++i)
6998 conversion *t1 = cand1->convs[i + off1];
6999 conversion *t2 = cand2->convs[i + off2];
7000 int comp = compare_ics (t1, t2);
7005 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7006 == cr_std + cr_promotion)
7007 && t1->kind == ck_std
7008 && t2->kind == ck_std
7009 && TREE_CODE (t1->type) == INTEGER_TYPE
7010 && TREE_CODE (t2->type) == INTEGER_TYPE
7011 && (TYPE_PRECISION (t1->type)
7012 == TYPE_PRECISION (t2->type))
7013 && (TYPE_UNSIGNED (t1->u.next->type)
7014 || (TREE_CODE (t1->u.next->type)
7017 tree type = t1->u.next->type;
7019 struct z_candidate *w, *l;
7021 type1 = t1->type, type2 = t2->type,
7022 w = cand1, l = cand2;
7024 type1 = t2->type, type2 = t1->type,
7025 w = cand2, l = cand1;
7029 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7030 type, type1, type2);
7031 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7037 if (winner && comp != winner)
7046 /* warn about confusing overload resolution for user-defined conversions,
7047 either between a constructor and a conversion op, or between two
7049 if (winner && warn_conversion && cand1->second_conv
7050 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7051 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7053 struct z_candidate *w, *l;
7054 bool give_warning = false;
7057 w = cand1, l = cand2;
7059 w = cand2, l = cand1;
7061 /* We don't want to complain about `X::operator T1 ()'
7062 beating `X::operator T2 () const', when T2 is a no less
7063 cv-qualified version of T1. */
7064 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7065 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7067 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7068 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7070 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7075 if (!comp_ptr_ttypes (t, f))
7076 give_warning = true;
7079 give_warning = true;
7085 tree source = source_type (w->convs[0]);
7086 if (! DECL_CONSTRUCTOR_P (w->fn))
7087 source = TREE_TYPE (source);
7088 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7089 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7090 source, w->second_conv->type))
7092 inform (input_location, " because conversion sequence for the argument is better");
7103 F1 is a non-template function and F2 is a template function
7106 if (!cand1->template_decl && cand2->template_decl)
7108 else if (cand1->template_decl && !cand2->template_decl)
7112 F1 and F2 are template functions and the function template for F1 is
7113 more specialized than the template for F2 according to the partial
7116 if (cand1->template_decl && cand2->template_decl)
7118 winner = more_specialized_fn
7119 (TI_TEMPLATE (cand1->template_decl),
7120 TI_TEMPLATE (cand2->template_decl),
7121 /* [temp.func.order]: The presence of unused ellipsis and default
7122 arguments has no effect on the partial ordering of function
7123 templates. add_function_candidate() will not have
7124 counted the "this" argument for constructors. */
7125 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7131 the context is an initialization by user-defined conversion (see
7132 _dcl.init_ and _over.match.user_) and the standard conversion
7133 sequence from the return type of F1 to the destination type (i.e.,
7134 the type of the entity being initialized) is a better conversion
7135 sequence than the standard conversion sequence from the return type
7136 of F2 to the destination type. */
7138 if (cand1->second_conv)
7140 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7145 /* Check whether we can discard a builtin candidate, either because we
7146 have two identical ones or matching builtin and non-builtin candidates.
7148 (Pedantically in the latter case the builtin which matched the user
7149 function should not be added to the overload set, but we spot it here.
7152 ... the builtin candidates include ...
7153 - do not have the same parameter type list as any non-template
7154 non-member candidate. */
7156 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7157 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7159 for (i = 0; i < len; ++i)
7160 if (!same_type_p (cand1->convs[i]->type,
7161 cand2->convs[i]->type))
7163 if (i == cand1->num_convs)
7165 if (cand1->fn == cand2->fn)
7166 /* Two built-in candidates; arbitrarily pick one. */
7168 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7169 /* cand1 is built-in; prefer cand2. */
7172 /* cand2 is built-in; prefer cand1. */
7177 /* If the two function declarations represent the same function (this can
7178 happen with declarations in multiple scopes and arg-dependent lookup),
7179 arbitrarily choose one. But first make sure the default args we're
7181 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7182 && equal_functions (cand1->fn, cand2->fn))
7184 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7185 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7187 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7189 for (i = 0; i < len; ++i)
7191 /* Don't crash if the fn is variadic. */
7194 parms1 = TREE_CHAIN (parms1);
7195 parms2 = TREE_CHAIN (parms2);
7199 parms1 = TREE_CHAIN (parms1);
7201 parms2 = TREE_CHAIN (parms2);
7205 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7206 TREE_PURPOSE (parms2)))
7210 permerror (input_location, "default argument mismatch in "
7211 "overload resolution");
7212 inform (input_location,
7213 " candidate 1: %q+#F", cand1->fn);
7214 inform (input_location,
7215 " candidate 2: %q+#F", cand2->fn);
7218 add_warning (cand1, cand2);
7221 parms1 = TREE_CHAIN (parms1);
7222 parms2 = TREE_CHAIN (parms2);
7230 /* Extension: If the worst conversion for one candidate is worse than the
7231 worst conversion for the other, take the first. */
7234 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7235 struct z_candidate *w = 0, *l = 0;
7237 for (i = 0; i < len; ++i)
7239 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7240 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7241 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7242 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7245 winner = 1, w = cand1, l = cand2;
7247 winner = -1, w = cand2, l = cand1;
7252 pedwarn (input_location, 0,
7253 "ISO C++ says that these are ambiguous, even "
7254 "though the worst conversion for the first is better than "
7255 "the worst conversion for the second:");
7256 print_z_candidate (_("candidate 1:"), w);
7257 print_z_candidate (_("candidate 2:"), l);
7265 gcc_assert (!winner);
7269 /* Given a list of candidates for overloading, find the best one, if any.
7270 This algorithm has a worst case of O(2n) (winner is last), and a best
7271 case of O(n/2) (totally ambiguous); much better than a sorting
7274 static struct z_candidate *
7275 tourney (struct z_candidate *candidates)
7277 struct z_candidate *champ = candidates, *challenger;
7279 int champ_compared_to_predecessor = 0;
7281 /* Walk through the list once, comparing each current champ to the next
7282 candidate, knocking out a candidate or two with each comparison. */
7284 for (challenger = champ->next; challenger; )
7286 fate = joust (champ, challenger, 0);
7288 challenger = challenger->next;
7293 champ = challenger->next;
7296 champ_compared_to_predecessor = 0;
7301 champ_compared_to_predecessor = 1;
7304 challenger = champ->next;
7308 /* Make sure the champ is better than all the candidates it hasn't yet
7309 been compared to. */
7311 for (challenger = candidates;
7313 && !(champ_compared_to_predecessor && challenger->next == champ);
7314 challenger = challenger->next)
7316 fate = joust (champ, challenger, 0);
7324 /* Returns nonzero if things of type FROM can be converted to TO. */
7327 can_convert (tree to, tree from)
7329 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7332 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7335 can_convert_arg (tree to, tree from, tree arg, int flags)
7341 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7342 p = conversion_obstack_alloc (0);
7344 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7346 ok_p = (t && !t->bad_p);
7348 /* Free all the conversions we allocated. */
7349 obstack_free (&conversion_obstack, p);
7354 /* Like can_convert_arg, but allows dubious conversions as well. */
7357 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7362 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7363 p = conversion_obstack_alloc (0);
7364 /* Try to perform the conversion. */
7365 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7367 /* Free all the conversions we allocated. */
7368 obstack_free (&conversion_obstack, p);
7373 /* Convert EXPR to TYPE. Return the converted expression.
7375 Note that we allow bad conversions here because by the time we get to
7376 this point we are committed to doing the conversion. If we end up
7377 doing a bad conversion, convert_like will complain. */
7380 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7385 if (error_operand_p (expr))
7386 return error_mark_node;
7388 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7389 p = conversion_obstack_alloc (0);
7391 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7397 if (complain & tf_error)
7399 /* If expr has unknown type, then it is an overloaded function.
7400 Call instantiate_type to get good error messages. */
7401 if (TREE_TYPE (expr) == unknown_type_node)
7402 instantiate_type (type, expr, complain);
7403 else if (invalid_nonstatic_memfn_p (expr, complain))
7404 /* We gave an error. */;
7406 error ("could not convert %qE to %qT", expr, type);
7408 expr = error_mark_node;
7410 else if (processing_template_decl)
7412 /* In a template, we are only concerned about determining the
7413 type of non-dependent expressions, so we do not have to
7414 perform the actual conversion. */
7415 if (TREE_TYPE (expr) != type)
7416 expr = build_nop (type, expr);
7419 expr = convert_like (conv, expr, complain);
7421 /* Free all the conversions we allocated. */
7422 obstack_free (&conversion_obstack, p);
7428 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7430 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7433 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7434 permitted. If the conversion is valid, the converted expression is
7435 returned. Otherwise, NULL_TREE is returned, except in the case
7436 that TYPE is a class type; in that case, an error is issued. If
7437 C_CAST_P is true, then this direction initialization is taking
7438 place as part of a static_cast being attempted as part of a C-style
7442 perform_direct_initialization_if_possible (tree type,
7445 tsubst_flags_t complain)
7450 if (type == error_mark_node || error_operand_p (expr))
7451 return error_mark_node;
7454 If the destination type is a (possibly cv-qualified) class type:
7456 -- If the initialization is direct-initialization ...,
7457 constructors are considered. ... If no constructor applies, or
7458 the overload resolution is ambiguous, the initialization is
7460 if (CLASS_TYPE_P (type))
7462 VEC(tree,gc) *args = make_tree_vector_single (expr);
7463 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7464 &args, type, LOOKUP_NORMAL, complain);
7465 release_tree_vector (args);
7466 return build_cplus_new (type, expr);
7469 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7470 p = conversion_obstack_alloc (0);
7472 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7475 if (!conv || conv->bad_p)
7478 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7479 /*issue_conversion_warnings=*/false,
7481 tf_warning_or_error);
7483 /* Free all the conversions we allocated. */
7484 obstack_free (&conversion_obstack, p);
7489 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7490 is being bound to a temporary. Create and return a new VAR_DECL
7491 with the indicated TYPE; this variable will store the value to
7492 which the reference is bound. */
7495 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7499 /* Create the variable. */
7500 var = create_temporary_var (type);
7502 /* Register the variable. */
7503 if (TREE_STATIC (decl))
7505 /* Namespace-scope or local static; give it a mangled name. */
7508 TREE_STATIC (var) = 1;
7509 name = mangle_ref_init_variable (decl);
7510 DECL_NAME (var) = name;
7511 SET_DECL_ASSEMBLER_NAME (var, name);
7512 var = pushdecl_top_level (var);
7515 /* Create a new cleanup level if necessary. */
7516 maybe_push_cleanup_level (type);
7521 /* EXPR is the initializer for a variable DECL of reference or
7522 std::initializer_list type. Create, push and return a new VAR_DECL
7523 for the initializer so that it will live as long as DECL. Any
7524 cleanup for the new variable is returned through CLEANUP, and the
7525 code to initialize the new variable is returned through INITP. */
7528 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7534 /* Create the temporary variable. */
7535 type = TREE_TYPE (expr);
7536 var = make_temporary_var_for_ref_to_temp (decl, type);
7537 layout_decl (var, 0);
7538 /* If the rvalue is the result of a function call it will be
7539 a TARGET_EXPR. If it is some other construct (such as a
7540 member access expression where the underlying object is
7541 itself the result of a function call), turn it into a
7542 TARGET_EXPR here. It is important that EXPR be a
7543 TARGET_EXPR below since otherwise the INIT_EXPR will
7544 attempt to make a bitwise copy of EXPR to initialize
7546 if (TREE_CODE (expr) != TARGET_EXPR)
7547 expr = get_target_expr (expr);
7548 /* Create the INIT_EXPR that will initialize the temporary
7550 init = build2 (INIT_EXPR, type, var, expr);
7551 if (at_function_scope_p ())
7553 add_decl_expr (var);
7555 if (TREE_STATIC (var))
7556 init = add_stmt_to_compound (init, register_dtor_fn (var));
7558 *cleanup = cxx_maybe_build_cleanup (var);
7560 /* We must be careful to destroy the temporary only
7561 after its initialization has taken place. If the
7562 initialization throws an exception, then the
7563 destructor should not be run. We cannot simply
7564 transform INIT into something like:
7566 (INIT, ({ CLEANUP_STMT; }))
7568 because emit_local_var always treats the
7569 initializer as a full-expression. Thus, the
7570 destructor would run too early; it would run at the
7571 end of initializing the reference variable, rather
7572 than at the end of the block enclosing the
7575 The solution is to pass back a cleanup expression
7576 which the caller is responsible for attaching to
7577 the statement tree. */
7581 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7582 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7583 static_aggregates = tree_cons (NULL_TREE, var,
7591 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7592 initializing a variable of that TYPE. If DECL is non-NULL, it is
7593 the VAR_DECL being initialized with the EXPR. (In that case, the
7594 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7595 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7596 return, if *CLEANUP is no longer NULL, it will be an expression
7597 that should be pushed as a cleanup after the returned expression
7598 is used to initialize DECL.
7600 Return the converted expression. */
7603 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7608 if (type == error_mark_node || error_operand_p (expr))
7609 return error_mark_node;
7611 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7612 p = conversion_obstack_alloc (0);
7614 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7616 if (!conv || conv->bad_p)
7618 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7619 && !TYPE_REF_IS_RVALUE (type)
7620 && !real_lvalue_p (expr))
7621 error ("invalid initialization of non-const reference of "
7622 "type %qT from a temporary of type %qT",
7623 type, TREE_TYPE (expr));
7625 error ("invalid initialization of reference of type "
7626 "%qT from expression of type %qT", type,
7628 return error_mark_node;
7631 /* If DECL is non-NULL, then this special rule applies:
7635 The temporary to which the reference is bound or the temporary
7636 that is the complete object to which the reference is bound
7637 persists for the lifetime of the reference.
7639 The temporaries created during the evaluation of the expression
7640 initializing the reference, except the temporary to which the
7641 reference is bound, are destroyed at the end of the
7642 full-expression in which they are created.
7644 In that case, we store the converted expression into a new
7645 VAR_DECL in a new scope.
7647 However, we want to be careful not to create temporaries when
7648 they are not required. For example, given:
7651 struct D : public B {};
7655 there is no need to copy the return value from "f"; we can just
7656 extend its lifetime. Similarly, given:
7659 struct T { operator S(); };
7663 we can extend the lifetime of the return value of the conversion
7665 gcc_assert (conv->kind == ck_ref_bind);
7669 tree base_conv_type;
7671 /* Skip over the REF_BIND. */
7672 conv = conv->u.next;
7673 /* If the next conversion is a BASE_CONV, skip that too -- but
7674 remember that the conversion was required. */
7675 if (conv->kind == ck_base)
7677 base_conv_type = conv->type;
7678 conv = conv->u.next;
7681 base_conv_type = NULL_TREE;
7682 /* Perform the remainder of the conversion. */
7683 expr = convert_like_real (conv, expr,
7684 /*fn=*/NULL_TREE, /*argnum=*/0,
7686 /*issue_conversion_warnings=*/true,
7688 tf_warning_or_error);
7689 if (error_operand_p (expr))
7690 expr = error_mark_node;
7693 if (!lvalue_or_rvalue_with_address_p (expr))
7696 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7697 /* Use its address to initialize the reference variable. */
7698 expr = build_address (var);
7700 expr = convert_to_base (expr,
7701 build_pointer_type (base_conv_type),
7702 /*check_access=*/true,
7704 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7707 /* Take the address of EXPR. */
7708 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7709 /* If a BASE_CONV was required, perform it now. */
7711 expr = (perform_implicit_conversion
7712 (build_pointer_type (base_conv_type), expr,
7713 tf_warning_or_error));
7714 expr = build_nop (type, expr);
7718 /* Perform the conversion. */
7719 expr = convert_like (conv, expr, tf_warning_or_error);
7721 /* Free all the conversions we allocated. */
7722 obstack_free (&conversion_obstack, p);
7727 /* Returns true iff TYPE is some variant of std::initializer_list. */
7730 is_std_init_list (tree type)
7732 return (CLASS_TYPE_P (type)
7733 && CP_TYPE_CONTEXT (type) == std_node
7734 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7737 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7738 will accept an argument list of a single std::initializer_list<T>. */
7741 is_list_ctor (tree decl)
7743 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7746 if (!args || args == void_list_node)
7749 arg = non_reference (TREE_VALUE (args));
7750 if (!is_std_init_list (arg))
7753 args = TREE_CHAIN (args);
7755 if (args && args != void_list_node && !TREE_PURPOSE (args))
7756 /* There are more non-defaulted parms. */
7762 #include "gt-cp-call.h"