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);
1781 flags |= LOOKUP_ONLYCONVERTING;
1783 for (i = 0; i < 2; ++i)
1788 t = implicit_conversion (types[i], argtypes[i], args[i],
1789 /*c_cast_p=*/false, flags);
1793 /* We need something for printing the candidate. */
1794 t = build_identity_conv (types[i], NULL_TREE);
1801 /* For COND_EXPR we rearranged the arguments; undo that now. */
1804 convs[2] = convs[1];
1805 convs[1] = convs[0];
1806 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1807 /*c_cast_p=*/false, flags);
1814 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1816 /*access_path=*/NULL_TREE,
1817 /*conversion_path=*/NULL_TREE,
1822 is_complete (tree t)
1824 return COMPLETE_TYPE_P (complete_type (t));
1827 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1830 promoted_arithmetic_type_p (tree type)
1834 In this section, the term promoted integral type is used to refer
1835 to those integral types which are preserved by integral promotion
1836 (including e.g. int and long but excluding e.g. char).
1837 Similarly, the term promoted arithmetic type refers to promoted
1838 integral types plus floating types. */
1839 return ((CP_INTEGRAL_TYPE_P (type)
1840 && same_type_p (type_promotes_to (type), type))
1841 || TREE_CODE (type) == REAL_TYPE);
1844 /* Create any builtin operator overload candidates for the operator in
1845 question given the converted operand types TYPE1 and TYPE2. The other
1846 args are passed through from add_builtin_candidates to
1847 build_builtin_candidate.
1849 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1850 If CODE is requires candidates operands of the same type of the kind
1851 of which TYPE1 and TYPE2 are, we add both candidates
1852 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1855 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1856 enum tree_code code2, tree fnname, tree type1,
1857 tree type2, tree *args, tree *argtypes, int flags)
1861 case POSTINCREMENT_EXPR:
1862 case POSTDECREMENT_EXPR:
1863 args[1] = integer_zero_node;
1864 type2 = integer_type_node;
1873 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1874 and VQ is either volatile or empty, there exist candidate operator
1875 functions of the form
1876 VQ T& operator++(VQ T&);
1877 T operator++(VQ T&, int);
1878 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1879 type other than bool, and VQ is either volatile or empty, there exist
1880 candidate operator functions of the form
1881 VQ T& operator--(VQ T&);
1882 T operator--(VQ T&, int);
1883 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1884 complete object type, and VQ is either volatile or empty, there exist
1885 candidate operator functions of the form
1886 T*VQ& operator++(T*VQ&);
1887 T*VQ& operator--(T*VQ&);
1888 T* operator++(T*VQ&, int);
1889 T* operator--(T*VQ&, int); */
1891 case POSTDECREMENT_EXPR:
1892 case PREDECREMENT_EXPR:
1893 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1895 case POSTINCREMENT_EXPR:
1896 case PREINCREMENT_EXPR:
1897 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1899 type1 = build_reference_type (type1);
1904 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1905 exist candidate operator functions of the form
1909 8 For every function type T, there exist candidate operator functions of
1911 T& operator*(T*); */
1914 if (TREE_CODE (type1) == POINTER_TYPE
1915 && (TYPE_PTROB_P (type1)
1916 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1920 /* 9 For every type T, there exist candidate operator functions of the form
1923 10For every promoted arithmetic type T, there exist candidate operator
1924 functions of the form
1928 case UNARY_PLUS_EXPR: /* unary + */
1929 if (TREE_CODE (type1) == POINTER_TYPE)
1932 if (ARITHMETIC_TYPE_P (type1))
1936 /* 11For every promoted integral type T, there exist candidate operator
1937 functions of the form
1941 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1945 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1946 is the same type as C2 or is a derived class of C2, T is a complete
1947 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1948 there exist candidate operator functions of the form
1949 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1950 where CV12 is the union of CV1 and CV2. */
1953 if (TREE_CODE (type1) == POINTER_TYPE
1954 && TYPE_PTR_TO_MEMBER_P (type2))
1956 tree c1 = TREE_TYPE (type1);
1957 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1959 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1960 && (TYPE_PTRMEMFUNC_P (type2)
1961 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1966 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1967 didate operator functions of the form
1972 bool operator<(L, R);
1973 bool operator>(L, R);
1974 bool operator<=(L, R);
1975 bool operator>=(L, R);
1976 bool operator==(L, R);
1977 bool operator!=(L, R);
1978 where LR is the result of the usual arithmetic conversions between
1981 14For every pair of types T and I, where T is a cv-qualified or cv-
1982 unqualified complete object type and I is a promoted integral type,
1983 there exist candidate operator functions of the form
1984 T* operator+(T*, I);
1985 T& operator[](T*, I);
1986 T* operator-(T*, I);
1987 T* operator+(I, T*);
1988 T& operator[](I, T*);
1990 15For every T, where T is a pointer to complete object type, there exist
1991 candidate operator functions of the form112)
1992 ptrdiff_t operator-(T, T);
1994 16For every pointer or enumeration type T, there exist candidate operator
1995 functions of the form
1996 bool operator<(T, T);
1997 bool operator>(T, T);
1998 bool operator<=(T, T);
1999 bool operator>=(T, T);
2000 bool operator==(T, T);
2001 bool operator!=(T, T);
2003 17For every pointer to member type T, there exist candidate operator
2004 functions of the form
2005 bool operator==(T, T);
2006 bool operator!=(T, T); */
2009 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2011 if (TYPE_PTROB_P (type1)
2012 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2014 type2 = ptrdiff_type_node;
2018 case TRUNC_DIV_EXPR:
2019 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2025 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2026 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2028 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2033 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2045 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2047 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2049 if (TREE_CODE (type1) == ENUMERAL_TYPE
2050 && TREE_CODE (type2) == ENUMERAL_TYPE)
2052 if (TYPE_PTR_P (type1)
2053 && null_ptr_cst_p (args[1])
2054 && !uses_template_parms (type1))
2059 if (null_ptr_cst_p (args[0])
2060 && TYPE_PTR_P (type2)
2061 && !uses_template_parms (type2))
2069 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2072 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2074 type1 = ptrdiff_type_node;
2077 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2079 type2 = ptrdiff_type_node;
2084 /* 18For every pair of promoted integral types L and R, there exist candi-
2085 date operator functions of the form
2092 where LR is the result of the usual arithmetic conversions between
2095 case TRUNC_MOD_EXPR:
2101 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2105 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2106 type, VQ is either volatile or empty, and R is a promoted arithmetic
2107 type, there exist candidate operator functions of the form
2108 VQ L& operator=(VQ L&, R);
2109 VQ L& operator*=(VQ L&, R);
2110 VQ L& operator/=(VQ L&, R);
2111 VQ L& operator+=(VQ L&, R);
2112 VQ L& operator-=(VQ L&, R);
2114 20For every pair T, VQ), where T is any type and VQ is either volatile
2115 or empty, there exist candidate operator functions of the form
2116 T*VQ& operator=(T*VQ&, T*);
2118 21For every pair T, VQ), where T is a pointer to member type and VQ is
2119 either volatile or empty, there exist candidate operator functions of
2121 VQ T& operator=(VQ T&, T);
2123 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2124 unqualified complete object type, VQ is either volatile or empty, and
2125 I is a promoted integral type, there exist candidate operator func-
2127 T*VQ& operator+=(T*VQ&, I);
2128 T*VQ& operator-=(T*VQ&, I);
2130 23For every triple L, VQ, R), where L is an integral or enumeration
2131 type, VQ is either volatile or empty, and R is a promoted integral
2132 type, there exist candidate operator functions of the form
2134 VQ L& operator%=(VQ L&, R);
2135 VQ L& operator<<=(VQ L&, R);
2136 VQ L& operator>>=(VQ L&, R);
2137 VQ L& operator&=(VQ L&, R);
2138 VQ L& operator^=(VQ L&, R);
2139 VQ L& operator|=(VQ L&, R); */
2146 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2148 type2 = ptrdiff_type_node;
2152 case TRUNC_DIV_EXPR:
2153 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2157 case TRUNC_MOD_EXPR:
2163 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2168 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2170 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2171 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2172 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2173 || ((TYPE_PTRMEMFUNC_P (type1)
2174 || TREE_CODE (type1) == POINTER_TYPE)
2175 && null_ptr_cst_p (args[1])))
2185 type1 = build_reference_type (type1);
2191 For every pair of promoted arithmetic types L and R, there
2192 exist candidate operator functions of the form
2194 LR operator?(bool, L, R);
2196 where LR is the result of the usual arithmetic conversions
2197 between types L and R.
2199 For every type T, where T is a pointer or pointer-to-member
2200 type, there exist candidate operator functions of the form T
2201 operator?(bool, T, T); */
2203 if (promoted_arithmetic_type_p (type1)
2204 && promoted_arithmetic_type_p (type2))
2208 /* Otherwise, the types should be pointers. */
2209 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2210 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2213 /* We don't check that the two types are the same; the logic
2214 below will actually create two candidates; one in which both
2215 parameter types are TYPE1, and one in which both parameter
2223 /* If we're dealing with two pointer types or two enumeral types,
2224 we need candidates for both of them. */
2225 if (type2 && !same_type_p (type1, type2)
2226 && TREE_CODE (type1) == TREE_CODE (type2)
2227 && (TREE_CODE (type1) == REFERENCE_TYPE
2228 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2229 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2230 || TYPE_PTRMEMFUNC_P (type1)
2231 || MAYBE_CLASS_TYPE_P (type1)
2232 || TREE_CODE (type1) == ENUMERAL_TYPE))
2234 build_builtin_candidate
2235 (candidates, fnname, type1, type1, args, argtypes, flags);
2236 build_builtin_candidate
2237 (candidates, fnname, type2, type2, args, argtypes, flags);
2241 build_builtin_candidate
2242 (candidates, fnname, type1, type2, args, argtypes, flags);
2246 type_decays_to (tree type)
2248 if (TREE_CODE (type) == ARRAY_TYPE)
2249 return build_pointer_type (TREE_TYPE (type));
2250 if (TREE_CODE (type) == FUNCTION_TYPE)
2251 return build_pointer_type (type);
2255 /* There are three conditions of builtin candidates:
2257 1) bool-taking candidates. These are the same regardless of the input.
2258 2) pointer-pair taking candidates. These are generated for each type
2259 one of the input types converts to.
2260 3) arithmetic candidates. According to the standard, we should generate
2261 all of these, but I'm trying not to...
2263 Here we generate a superset of the possible candidates for this particular
2264 case. That is a subset of the full set the standard defines, plus some
2265 other cases which the standard disallows. add_builtin_candidate will
2266 filter out the invalid set. */
2269 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2270 enum tree_code code2, tree fnname, tree *args,
2275 tree type, argtypes[3];
2276 /* TYPES[i] is the set of possible builtin-operator parameter types
2277 we will consider for the Ith argument. These are represented as
2278 a TREE_LIST; the TREE_VALUE of each node is the potential
2282 for (i = 0; i < 3; ++i)
2285 argtypes[i] = unlowered_expr_type (args[i]);
2287 argtypes[i] = NULL_TREE;
2292 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2293 and VQ is either volatile or empty, there exist candidate operator
2294 functions of the form
2295 VQ T& operator++(VQ T&); */
2297 case POSTINCREMENT_EXPR:
2298 case PREINCREMENT_EXPR:
2299 case POSTDECREMENT_EXPR:
2300 case PREDECREMENT_EXPR:
2305 /* 24There also exist candidate operator functions of the form
2306 bool operator!(bool);
2307 bool operator&&(bool, bool);
2308 bool operator||(bool, bool); */
2310 case TRUTH_NOT_EXPR:
2311 build_builtin_candidate
2312 (candidates, fnname, boolean_type_node,
2313 NULL_TREE, args, argtypes, flags);
2316 case TRUTH_ORIF_EXPR:
2317 case TRUTH_ANDIF_EXPR:
2318 build_builtin_candidate
2319 (candidates, fnname, boolean_type_node,
2320 boolean_type_node, args, argtypes, flags);
2342 types[0] = types[1] = NULL_TREE;
2344 for (i = 0; i < 2; ++i)
2348 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2352 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2355 convs = lookup_conversions (argtypes[i]);
2357 if (code == COND_EXPR)
2359 if (real_lvalue_p (args[i]))
2360 types[i] = tree_cons
2361 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2363 types[i] = tree_cons
2364 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2370 for (; convs; convs = TREE_CHAIN (convs))
2372 type = TREE_TYPE (convs);
2375 && (TREE_CODE (type) != REFERENCE_TYPE
2376 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2379 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2380 types[i] = tree_cons (NULL_TREE, type, types[i]);
2382 type = non_reference (type);
2383 if (i != 0 || ! ref1)
2385 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2386 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2387 types[i] = tree_cons (NULL_TREE, type, types[i]);
2388 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2389 type = type_promotes_to (type);
2392 if (! value_member (type, types[i]))
2393 types[i] = tree_cons (NULL_TREE, type, types[i]);
2398 if (code == COND_EXPR && real_lvalue_p (args[i]))
2399 types[i] = tree_cons
2400 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2401 type = non_reference (argtypes[i]);
2402 if (i != 0 || ! ref1)
2404 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2405 if (enum_p && UNSCOPED_ENUM_P (type))
2406 types[i] = tree_cons (NULL_TREE, type, types[i]);
2407 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2408 type = type_promotes_to (type);
2410 types[i] = tree_cons (NULL_TREE, type, types[i]);
2414 /* Run through the possible parameter types of both arguments,
2415 creating candidates with those parameter types. */
2416 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2419 for (type = types[1]; type; type = TREE_CHAIN (type))
2420 add_builtin_candidate
2421 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2422 TREE_VALUE (type), args, argtypes, flags);
2424 add_builtin_candidate
2425 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2426 NULL_TREE, args, argtypes, flags);
2431 /* If TMPL can be successfully instantiated as indicated by
2432 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2434 TMPL is the template. EXPLICIT_TARGS are any explicit template
2435 arguments. ARGLIST is the arguments provided at the call-site.
2436 This does not change ARGLIST. The RETURN_TYPE is the desired type
2437 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2438 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2439 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2441 static struct z_candidate*
2442 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2443 tree ctype, tree explicit_targs, tree first_arg,
2444 const VEC(tree,gc) *arglist, tree return_type,
2445 tree access_path, tree conversion_path,
2446 int flags, tree obj, unification_kind_t strict)
2448 int ntparms = DECL_NTPARMS (tmpl);
2449 tree targs = make_tree_vec (ntparms);
2451 int skip_without_in_chrg;
2452 tree first_arg_without_in_chrg;
2453 tree *args_without_in_chrg;
2454 unsigned int nargs_without_in_chrg;
2455 unsigned int ia, ix;
2457 struct z_candidate *cand;
2461 nargs = (first_arg == NULL_TREE ? 0 : 1) + VEC_length (tree, arglist);
2463 skip_without_in_chrg = 0;
2465 first_arg_without_in_chrg = first_arg;
2467 /* We don't do deduction on the in-charge parameter, the VTT
2468 parameter or 'this'. */
2469 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2471 if (first_arg_without_in_chrg != NULL_TREE)
2472 first_arg_without_in_chrg = NULL_TREE;
2474 ++skip_without_in_chrg;
2477 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2478 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2479 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2481 if (first_arg_without_in_chrg != NULL_TREE)
2482 first_arg_without_in_chrg = NULL_TREE;
2484 ++skip_without_in_chrg;
2487 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2488 + (VEC_length (tree, arglist)
2489 - skip_without_in_chrg));
2490 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2492 if (first_arg_without_in_chrg != NULL_TREE)
2494 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2497 for (ix = skip_without_in_chrg;
2498 VEC_iterate (tree, arglist, ix, arg);
2501 args_without_in_chrg[ia] = arg;
2504 gcc_assert (ia == nargs_without_in_chrg);
2506 i = fn_type_unification (tmpl, explicit_targs, targs,
2507 args_without_in_chrg,
2508 nargs_without_in_chrg,
2509 return_type, strict, flags);
2514 fn = instantiate_template (tmpl, targs, tf_none);
2515 if (fn == error_mark_node)
2520 A member function template is never instantiated to perform the
2521 copy of a class object to an object of its class type.
2523 It's a little unclear what this means; the standard explicitly
2524 does allow a template to be used to copy a class. For example,
2529 template <class T> A(const T&);
2532 void g () { A a (f ()); }
2534 the member template will be used to make the copy. The section
2535 quoted above appears in the paragraph that forbids constructors
2536 whose only parameter is (a possibly cv-qualified variant of) the
2537 class type, and a logical interpretation is that the intent was
2538 to forbid the instantiation of member templates which would then
2540 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2542 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2543 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2548 if (obj != NULL_TREE)
2549 /* Aha, this is a conversion function. */
2550 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2551 access_path, conversion_path);
2553 cand = add_function_candidate (candidates, fn, ctype,
2554 first_arg, arglist, access_path,
2555 conversion_path, flags);
2556 if (DECL_TI_TEMPLATE (fn) != tmpl)
2557 /* This situation can occur if a member template of a template
2558 class is specialized. Then, instantiate_template might return
2559 an instantiation of the specialization, in which case the
2560 DECL_TI_TEMPLATE field will point at the original
2561 specialization. For example:
2563 template <class T> struct S { template <class U> void f(U);
2564 template <> void f(int) {}; };
2568 Here, TMPL will be template <class U> S<double>::f(U).
2569 And, instantiate template will give us the specialization
2570 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2571 for this will point at template <class T> template <> S<T>::f(int),
2572 so that we can find the definition. For the purposes of
2573 overload resolution, however, we want the original TMPL. */
2574 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2576 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2582 static struct z_candidate *
2583 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2584 tree explicit_targs, tree first_arg,
2585 const VEC(tree,gc) *arglist, tree return_type,
2586 tree access_path, tree conversion_path, int flags,
2587 unification_kind_t strict)
2590 add_template_candidate_real (candidates, tmpl, ctype,
2591 explicit_targs, first_arg, arglist,
2592 return_type, access_path, conversion_path,
2593 flags, NULL_TREE, strict);
2597 static struct z_candidate *
2598 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2599 tree obj, tree first_arg,
2600 const VEC(tree,gc) *arglist,
2601 tree return_type, tree access_path,
2602 tree conversion_path)
2605 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2606 first_arg, arglist, return_type, access_path,
2607 conversion_path, 0, obj, DEDUCE_CONV);
2610 /* The CANDS are the set of candidates that were considered for
2611 overload resolution. Return the set of viable candidates. If none
2612 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2613 is true if a candidate should be considered viable only if it is
2616 static struct z_candidate*
2617 splice_viable (struct z_candidate *cands,
2621 struct z_candidate *viable;
2622 struct z_candidate **last_viable;
2623 struct z_candidate **cand;
2626 last_viable = &viable;
2627 *any_viable_p = false;
2632 struct z_candidate *c = *cand;
2633 if (strict_p ? c->viable == 1 : c->viable)
2638 last_viable = &c->next;
2639 *any_viable_p = true;
2645 return viable ? viable : cands;
2649 any_strictly_viable (struct z_candidate *cands)
2651 for (; cands; cands = cands->next)
2652 if (cands->viable == 1)
2657 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2658 words, it is about to become the "this" pointer for a member
2659 function call. Take the address of the object. */
2662 build_this (tree obj)
2664 /* In a template, we are only concerned about the type of the
2665 expression, so we can take a shortcut. */
2666 if (processing_template_decl)
2667 return build_address (obj);
2669 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2672 /* Returns true iff functions are equivalent. Equivalent functions are
2673 not '==' only if one is a function-local extern function or if
2674 both are extern "C". */
2677 equal_functions (tree fn1, tree fn2)
2679 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2680 || DECL_EXTERN_C_FUNCTION_P (fn1))
2681 return decls_match (fn1, fn2);
2685 /* Print information about one overload candidate CANDIDATE. MSGSTR
2686 is the text to print before the candidate itself.
2688 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2689 to have been run through gettext by the caller. This wart makes
2690 life simpler in print_z_candidates and for the translators. */
2693 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2695 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2697 if (candidate->num_convs == 3)
2698 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2699 candidate->convs[0]->type,
2700 candidate->convs[1]->type,
2701 candidate->convs[2]->type);
2702 else if (candidate->num_convs == 2)
2703 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2704 candidate->convs[0]->type,
2705 candidate->convs[1]->type);
2707 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2708 candidate->convs[0]->type);
2710 else if (TYPE_P (candidate->fn))
2711 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2712 else if (candidate->viable == -1)
2713 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2715 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2719 print_z_candidates (struct z_candidate *candidates)
2722 struct z_candidate *cand1;
2723 struct z_candidate **cand2;
2725 /* There may be duplicates in the set of candidates. We put off
2726 checking this condition as long as possible, since we have no way
2727 to eliminate duplicates from a set of functions in less than n^2
2728 time. Now we are about to emit an error message, so it is more
2729 permissible to go slowly. */
2730 for (cand1 = candidates; cand1; cand1 = cand1->next)
2732 tree fn = cand1->fn;
2733 /* Skip builtin candidates and conversion functions. */
2734 if (TREE_CODE (fn) != FUNCTION_DECL)
2736 cand2 = &cand1->next;
2739 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2740 && equal_functions (fn, (*cand2)->fn))
2741 *cand2 = (*cand2)->next;
2743 cand2 = &(*cand2)->next;
2750 str = _("candidates are:");
2751 print_z_candidate (str, candidates);
2752 if (candidates->next)
2754 /* Indent successive candidates by the width of the translation
2755 of the above string. */
2756 size_t len = gcc_gettext_width (str) + 1;
2757 char *spaces = (char *) alloca (len);
2758 memset (spaces, ' ', len-1);
2759 spaces[len - 1] = '\0';
2761 candidates = candidates->next;
2764 print_z_candidate (spaces, candidates);
2765 candidates = candidates->next;
2771 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2772 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2773 the result of the conversion function to convert it to the final
2774 desired type. Merge the two sequences into a single sequence,
2775 and return the merged sequence. */
2778 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2782 gcc_assert (user_seq->kind == ck_user);
2784 /* Find the end of the second conversion sequence. */
2786 while ((*t)->kind != ck_identity)
2787 t = &((*t)->u.next);
2789 /* Replace the identity conversion with the user conversion
2793 /* The entire sequence is a user-conversion sequence. */
2794 std_seq->user_conv_p = true;
2799 /* Returns the best overload candidate to perform the requested
2800 conversion. This function is used for three the overloading situations
2801 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2802 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2803 per [dcl.init.ref], so we ignore temporary bindings. */
2805 static struct z_candidate *
2806 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2808 struct z_candidate *candidates, *cand;
2809 tree fromtype = TREE_TYPE (expr);
2810 tree ctors = NULL_TREE;
2811 tree conv_fns = NULL_TREE;
2812 conversion *conv = NULL;
2813 tree first_arg = NULL_TREE;
2814 VEC(tree,gc) *args = NULL;
2818 /* We represent conversion within a hierarchy using RVALUE_CONV and
2819 BASE_CONV, as specified by [over.best.ics]; these become plain
2820 constructor calls, as specified in [dcl.init]. */
2821 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2822 || !DERIVED_FROM_P (totype, fromtype));
2824 if (MAYBE_CLASS_TYPE_P (totype))
2825 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2827 if (MAYBE_CLASS_TYPE_P (fromtype))
2829 tree to_nonref = non_reference (totype);
2830 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2831 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2832 && DERIVED_FROM_P (to_nonref, fromtype)))
2834 /* [class.conv.fct] A conversion function is never used to
2835 convert a (possibly cv-qualified) object to the (possibly
2836 cv-qualified) same object type (or a reference to it), to a
2837 (possibly cv-qualified) base class of that type (or a
2838 reference to it)... */
2841 conv_fns = lookup_conversions (fromtype);
2845 flags |= LOOKUP_NO_CONVERSION;
2847 /* It's OK to bind a temporary for converting constructor arguments, but
2848 not in converting the return value of a conversion operator. */
2849 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2850 flags &= ~LOOKUP_NO_TEMP_BIND;
2854 ctors = BASELINK_FUNCTIONS (ctors);
2856 first_arg = build_int_cst (build_pointer_type (totype), 0);
2857 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2858 && !TYPE_HAS_LIST_CTOR (totype))
2860 args = ctor_to_vec (expr);
2861 /* We still allow more conversions within an init-list. */
2862 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2863 /* But not for the copy ctor. */
2864 |LOOKUP_NO_COPY_CTOR_CONVERSION
2865 |LOOKUP_NO_NARROWING);
2868 args = make_tree_vector_single (expr);
2870 /* We should never try to call the abstract or base constructor
2872 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2873 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2875 for (; ctors; ctors = OVL_NEXT (ctors))
2877 tree ctor = OVL_CURRENT (ctors);
2878 if (DECL_NONCONVERTING_P (ctor)
2879 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2882 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2883 cand = add_template_candidate (&candidates, ctor, totype,
2884 NULL_TREE, first_arg, args, NULL_TREE,
2885 TYPE_BINFO (totype),
2886 TYPE_BINFO (totype),
2890 cand = add_function_candidate (&candidates, ctor, totype,
2891 first_arg, args, TYPE_BINFO (totype),
2892 TYPE_BINFO (totype),
2897 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2899 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2900 set, then this is copy-initialization. In that case, "The
2901 result of the call is then used to direct-initialize the
2902 object that is the destination of the copy-initialization."
2905 We represent this in the conversion sequence with an
2906 rvalue conversion, which means a constructor call. */
2907 if (TREE_CODE (totype) != REFERENCE_TYPE
2908 && !(convflags & LOOKUP_NO_TEMP_BIND))
2910 = build_conv (ck_rvalue, totype, cand->second_conv);
2915 first_arg = build_this (expr);
2917 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2920 tree conversion_path = TREE_PURPOSE (conv_fns);
2922 /* If we are called to convert to a reference type, we are trying to
2923 find an lvalue binding, so don't even consider temporaries. If
2924 we don't find an lvalue binding, the caller will try again to
2925 look for a temporary binding. */
2926 if (TREE_CODE (totype) == REFERENCE_TYPE)
2927 convflags |= LOOKUP_NO_TEMP_BIND;
2929 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2931 tree fn = OVL_CURRENT (fns);
2933 if (DECL_NONCONVERTING_P (fn)
2934 && (flags & LOOKUP_ONLYCONVERTING))
2937 /* [over.match.funcs] For conversion functions, the function
2938 is considered to be a member of the class of the implicit
2939 object argument for the purpose of defining the type of
2940 the implicit object parameter.
2942 So we pass fromtype as CTYPE to add_*_candidate. */
2944 if (TREE_CODE (fn) == TEMPLATE_DECL)
2945 cand = add_template_candidate (&candidates, fn, fromtype,
2947 first_arg, NULL, totype,
2948 TYPE_BINFO (fromtype),
2953 cand = add_function_candidate (&candidates, fn, fromtype,
2955 TYPE_BINFO (fromtype),
2962 = implicit_conversion (totype,
2963 TREE_TYPE (TREE_TYPE (cand->fn)),
2965 /*c_cast_p=*/false, convflags);
2967 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2968 copy-initialization. In that case, "The result of the
2969 call is then used to direct-initialize the object that is
2970 the destination of the copy-initialization." [dcl.init]
2972 We represent this in the conversion sequence with an
2973 rvalue conversion, which means a constructor call. But
2974 don't add a second rvalue conversion if there's already
2975 one there. Which there really shouldn't be, but it's
2976 harmless since we'd add it here anyway. */
2977 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2978 && !(convflags & LOOKUP_NO_TEMP_BIND))
2979 ics = build_conv (ck_rvalue, totype, ics);
2981 cand->second_conv = ics;
2985 else if (candidates->viable == 1 && ics->bad_p)
2991 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2995 cand = tourney (candidates);
2998 if (flags & LOOKUP_COMPLAIN)
3000 error ("conversion from %qT to %qT is ambiguous",
3002 print_z_candidates (candidates);
3005 cand = candidates; /* any one will do */
3006 cand->second_conv = build_ambiguous_conv (totype, expr);
3007 cand->second_conv->user_conv_p = true;
3008 if (!any_strictly_viable (candidates))
3009 cand->second_conv->bad_p = true;
3010 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3011 ambiguous conversion is no worse than another user-defined
3017 /* Build the user conversion sequence. */
3020 (DECL_CONSTRUCTOR_P (cand->fn)
3021 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3022 build_identity_conv (TREE_TYPE (expr), expr));
3025 /* Remember that this was a list-initialization. */
3026 if (flags & LOOKUP_NO_NARROWING)
3027 conv->check_narrowing = true;
3029 /* Combine it with the second conversion sequence. */
3030 cand->second_conv = merge_conversion_sequences (conv,
3033 if (cand->viable == -1)
3034 cand->second_conv->bad_p = true;
3040 build_user_type_conversion (tree totype, tree expr, int flags)
3042 struct z_candidate *cand
3043 = build_user_type_conversion_1 (totype, expr, flags);
3047 if (cand->second_conv->kind == ck_ambig)
3048 return error_mark_node;
3049 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3050 return convert_from_reference (expr);
3055 /* Do any initial processing on the arguments to a function call. */
3057 static VEC(tree,gc) *
3058 resolve_args (VEC(tree,gc) *args)
3063 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3065 if (error_operand_p (arg))
3067 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3069 error ("invalid use of void expression");
3072 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3078 /* Perform overload resolution on FN, which is called with the ARGS.
3080 Return the candidate function selected by overload resolution, or
3081 NULL if the event that overload resolution failed. In the case
3082 that overload resolution fails, *CANDIDATES will be the set of
3083 candidates considered, and ANY_VIABLE_P will be set to true or
3084 false to indicate whether or not any of the candidates were
3087 The ARGS should already have gone through RESOLVE_ARGS before this
3088 function is called. */
3090 static struct z_candidate *
3091 perform_overload_resolution (tree fn,
3092 const VEC(tree,gc) *args,
3093 struct z_candidate **candidates,
3096 struct z_candidate *cand;
3097 tree explicit_targs = NULL_TREE;
3098 int template_only = 0;
3101 *any_viable_p = true;
3104 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3105 || TREE_CODE (fn) == TEMPLATE_DECL
3106 || TREE_CODE (fn) == OVERLOAD
3107 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3109 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3111 explicit_targs = TREE_OPERAND (fn, 1);
3112 fn = TREE_OPERAND (fn, 0);
3116 /* Add the various candidate functions. */
3117 add_candidates (fn, args, explicit_targs, template_only,
3118 /*conversion_path=*/NULL_TREE,
3119 /*access_path=*/NULL_TREE,
3123 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3127 cand = tourney (*candidates);
3131 /* Return an expression for a call to FN (a namespace-scope function,
3132 or a static member function) with the ARGS. This may change
3136 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3137 tsubst_flags_t complain)
3139 struct z_candidate *candidates, *cand;
3144 if (args != NULL && *args != NULL)
3146 *args = resolve_args (*args);
3148 return error_mark_node;
3151 /* If this function was found without using argument dependent
3152 lookup, then we want to ignore any undeclared friend
3158 fn = remove_hidden_names (fn);
3161 if (complain & tf_error)
3162 error ("no matching function for call to %<%D(%A)%>",
3163 DECL_NAME (OVL_CURRENT (orig_fn)),
3164 build_tree_list_vec (*args));
3165 return error_mark_node;
3169 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3170 p = conversion_obstack_alloc (0);
3172 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3176 if (complain & tf_error)
3178 if (!any_viable_p && candidates && ! candidates->next)
3179 return cp_build_function_call_vec (candidates->fn, args, complain);
3180 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3181 fn = TREE_OPERAND (fn, 0);
3183 error ("no matching function for call to %<%D(%A)%>",
3184 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3186 error ("call of overloaded %<%D(%A)%> is ambiguous",
3187 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3189 print_z_candidates (candidates);
3191 result = error_mark_node;
3194 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3196 /* Free all the conversions we allocated. */
3197 obstack_free (&conversion_obstack, p);
3202 /* Build a call to a global operator new. FNNAME is the name of the
3203 operator (either "operator new" or "operator new[]") and ARGS are
3204 the arguments provided. This may change ARGS. *SIZE points to the
3205 total number of bytes required by the allocation, and is updated if
3206 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3207 be used. If this function determines that no cookie should be
3208 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3209 non-NULL, it will be set, upon return, to the allocation function
3213 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3214 tree *size, tree *cookie_size,
3218 struct z_candidate *candidates;
3219 struct z_candidate *cand;
3224 VEC_safe_insert (tree, gc, *args, 0, *size);
3225 *args = resolve_args (*args);
3227 return error_mark_node;
3233 If this lookup fails to find the name, or if the allocated type
3234 is not a class type, the allocation function's name is looked
3235 up in the global scope.
3237 we disregard block-scope declarations of "operator new". */
3238 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3240 /* Figure out what function is being called. */
3241 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3243 /* If no suitable function could be found, issue an error message
3248 error ("no matching function for call to %<%D(%A)%>",
3249 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3251 error ("call of overloaded %<%D(%A)%> is ambiguous",
3252 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3254 print_z_candidates (candidates);
3255 return error_mark_node;
3258 /* If a cookie is required, add some extra space. Whether
3259 or not a cookie is required cannot be determined until
3260 after we know which function was called. */
3263 bool use_cookie = true;
3264 if (!abi_version_at_least (2))
3266 /* In G++ 3.2, the check was implemented incorrectly; it
3267 looked at the placement expression, rather than the
3268 type of the function. */
3269 if (VEC_length (tree, *args) == 2
3270 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3278 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3279 /* Skip the size_t parameter. */
3280 arg_types = TREE_CHAIN (arg_types);
3281 /* Check the remaining parameters (if any). */
3283 && TREE_CHAIN (arg_types) == void_list_node
3284 && same_type_p (TREE_VALUE (arg_types),
3288 /* If we need a cookie, adjust the number of bytes allocated. */
3291 /* Update the total size. */
3292 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3293 /* Update the argument list to reflect the adjusted size. */
3294 VEC_replace (tree, *args, 0, *size);
3297 *cookie_size = NULL_TREE;
3300 /* Tell our caller which function we decided to call. */
3304 /* Build the CALL_EXPR. */
3305 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3308 /* Build a new call to operator(). This may change ARGS. */
3311 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3313 struct z_candidate *candidates = 0, *cand;
3314 tree fns, convs, first_mem_arg = NULL_TREE;
3315 tree type = TREE_TYPE (obj);
3317 tree result = NULL_TREE;
3320 if (error_operand_p (obj))
3321 return error_mark_node;
3323 obj = prep_operand (obj);
3325 if (TYPE_PTRMEMFUNC_P (type))
3327 if (complain & tf_error)
3328 /* It's no good looking for an overloaded operator() on a
3329 pointer-to-member-function. */
3330 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3331 return error_mark_node;
3334 if (TYPE_BINFO (type))
3336 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3337 if (fns == error_mark_node)
3338 return error_mark_node;
3343 if (args != NULL && *args != NULL)
3345 *args = resolve_args (*args);
3347 return error_mark_node;
3350 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3351 p = conversion_obstack_alloc (0);
3355 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3356 first_mem_arg = build_this (obj);
3358 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3360 tree fn = OVL_CURRENT (fns);
3361 if (TREE_CODE (fn) == TEMPLATE_DECL)
3362 add_template_candidate (&candidates, fn, base, NULL_TREE,
3363 first_mem_arg, *args, NULL_TREE,
3366 LOOKUP_NORMAL, DEDUCE_CALL);
3368 add_function_candidate
3369 (&candidates, fn, base, first_mem_arg, *args, TYPE_BINFO (type),
3370 TYPE_BINFO (type), LOOKUP_NORMAL);
3374 convs = lookup_conversions (type);
3376 for (; convs; convs = TREE_CHAIN (convs))
3378 tree fns = TREE_VALUE (convs);
3379 tree totype = TREE_TYPE (convs);
3381 if ((TREE_CODE (totype) == POINTER_TYPE
3382 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3383 || (TREE_CODE (totype) == REFERENCE_TYPE
3384 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3385 || (TREE_CODE (totype) == REFERENCE_TYPE
3386 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3387 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3388 for (; fns; fns = OVL_NEXT (fns))
3390 tree fn = OVL_CURRENT (fns);
3392 if (DECL_NONCONVERTING_P (fn))
3395 if (TREE_CODE (fn) == TEMPLATE_DECL)
3396 add_template_conv_candidate
3397 (&candidates, fn, obj, NULL_TREE, *args, totype,
3398 /*access_path=*/NULL_TREE,
3399 /*conversion_path=*/NULL_TREE);
3401 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3402 *args, /*conversion_path=*/NULL_TREE,
3403 /*access_path=*/NULL_TREE);
3407 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3410 if (complain & tf_error)
3412 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3413 build_tree_list_vec (*args));
3414 print_z_candidates (candidates);
3416 result = error_mark_node;
3420 cand = tourney (candidates);
3423 if (complain & tf_error)
3425 error ("call of %<(%T) (%A)%> is ambiguous",
3426 TREE_TYPE (obj), build_tree_list_vec (*args));
3427 print_z_candidates (candidates);
3429 result = error_mark_node;
3431 /* Since cand->fn will be a type, not a function, for a conversion
3432 function, we must be careful not to unconditionally look at
3434 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3435 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3436 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3439 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3441 obj = convert_from_reference (obj);
3442 result = cp_build_function_call_vec (obj, args, complain);
3446 /* Free all the conversions we allocated. */
3447 obstack_free (&conversion_obstack, p);
3453 op_error (enum tree_code code, enum tree_code code2,
3454 tree arg1, tree arg2, tree arg3, const char *problem)
3458 if (code == MODIFY_EXPR)
3459 opname = assignment_operator_name_info[code2].name;
3461 opname = operator_name_info[code].name;
3466 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3467 problem, arg1, arg2, arg3);
3470 case POSTINCREMENT_EXPR:
3471 case POSTDECREMENT_EXPR:
3472 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3476 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3481 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3486 error ("%s for %<operator%s%> in %<%E %s %E%>",
3487 problem, opname, arg1, opname, arg2);
3489 error ("%s for %<operator%s%> in %<%s%E%>",
3490 problem, opname, opname, arg1);
3495 /* Return the implicit conversion sequence that could be used to
3496 convert E1 to E2 in [expr.cond]. */
3499 conditional_conversion (tree e1, tree e2)
3501 tree t1 = non_reference (TREE_TYPE (e1));
3502 tree t2 = non_reference (TREE_TYPE (e2));
3508 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3509 implicitly converted (clause _conv_) to the type "reference to
3510 T2", subject to the constraint that in the conversion the
3511 reference must bind directly (_dcl.init.ref_) to E1. */
3512 if (real_lvalue_p (e2))
3514 conv = implicit_conversion (build_reference_type (t2),
3518 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3525 If E1 and E2 have class type, and the underlying class types are
3526 the same or one is a base class of the other: E1 can be converted
3527 to match E2 if the class of T2 is the same type as, or a base
3528 class of, the class of T1, and the cv-qualification of T2 is the
3529 same cv-qualification as, or a greater cv-qualification than, the
3530 cv-qualification of T1. If the conversion is applied, E1 is
3531 changed to an rvalue of type T2 that still refers to the original
3532 source class object (or the appropriate subobject thereof). */
3533 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3534 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3536 if (good_base && at_least_as_qualified_p (t2, t1))
3538 conv = build_identity_conv (t1, e1);
3539 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3540 TYPE_MAIN_VARIANT (t2)))
3541 conv = build_conv (ck_base, t2, conv);
3543 conv = build_conv (ck_rvalue, t2, conv);
3552 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3553 converted to the type that expression E2 would have if E2 were
3554 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3555 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3559 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3560 arguments to the conditional expression. */
3563 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3564 tsubst_flags_t complain)
3568 tree result = NULL_TREE;
3569 tree result_type = NULL_TREE;
3570 bool lvalue_p = true;
3571 struct z_candidate *candidates = 0;
3572 struct z_candidate *cand;
3575 /* As a G++ extension, the second argument to the conditional can be
3576 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3577 c'.) If the second operand is omitted, make sure it is
3578 calculated only once. */
3581 if (complain & tf_error)
3582 pedwarn (input_location, OPT_pedantic,
3583 "ISO C++ forbids omitting the middle term of a ?: expression");
3585 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3586 if (real_lvalue_p (arg1))
3587 arg2 = arg1 = stabilize_reference (arg1);
3589 arg2 = arg1 = save_expr (arg1);
3594 The first expression is implicitly converted to bool (clause
3596 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3598 /* If something has already gone wrong, just pass that fact up the
3600 if (error_operand_p (arg1)
3601 || error_operand_p (arg2)
3602 || error_operand_p (arg3))
3603 return error_mark_node;
3607 If either the second or the third operand has type (possibly
3608 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3609 array-to-pointer (_conv.array_), and function-to-pointer
3610 (_conv.func_) standard conversions are performed on the second
3611 and third operands. */
3612 arg2_type = unlowered_expr_type (arg2);
3613 arg3_type = unlowered_expr_type (arg3);
3614 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3616 /* Do the conversions. We don't these for `void' type arguments
3617 since it can't have any effect and since decay_conversion
3618 does not handle that case gracefully. */
3619 if (!VOID_TYPE_P (arg2_type))
3620 arg2 = decay_conversion (arg2);
3621 if (!VOID_TYPE_P (arg3_type))
3622 arg3 = decay_conversion (arg3);
3623 arg2_type = TREE_TYPE (arg2);
3624 arg3_type = TREE_TYPE (arg3);
3628 One of the following shall hold:
3630 --The second or the third operand (but not both) is a
3631 throw-expression (_except.throw_); the result is of the
3632 type of the other and is an rvalue.
3634 --Both the second and the third operands have type void; the
3635 result is of type void and is an rvalue.
3637 We must avoid calling force_rvalue for expressions of type
3638 "void" because it will complain that their value is being
3640 if (TREE_CODE (arg2) == THROW_EXPR
3641 && TREE_CODE (arg3) != THROW_EXPR)
3643 if (!VOID_TYPE_P (arg3_type))
3644 arg3 = force_rvalue (arg3);
3645 arg3_type = TREE_TYPE (arg3);
3646 result_type = arg3_type;
3648 else if (TREE_CODE (arg2) != THROW_EXPR
3649 && TREE_CODE (arg3) == THROW_EXPR)
3651 if (!VOID_TYPE_P (arg2_type))
3652 arg2 = force_rvalue (arg2);
3653 arg2_type = TREE_TYPE (arg2);
3654 result_type = arg2_type;
3656 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3657 result_type = void_type_node;
3660 if (complain & tf_error)
3662 if (VOID_TYPE_P (arg2_type))
3663 error ("second operand to the conditional operator "
3664 "is of type %<void%>, "
3665 "but the third operand is neither a throw-expression "
3666 "nor of type %<void%>");
3668 error ("third operand to the conditional operator "
3669 "is of type %<void%>, "
3670 "but the second operand is neither a throw-expression "
3671 "nor of type %<void%>");
3673 return error_mark_node;
3677 goto valid_operands;
3681 Otherwise, if the second and third operand have different types,
3682 and either has (possibly cv-qualified) class type, an attempt is
3683 made to convert each of those operands to the type of the other. */
3684 else if (!same_type_p (arg2_type, arg3_type)
3685 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3690 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3691 p = conversion_obstack_alloc (0);
3693 conv2 = conditional_conversion (arg2, arg3);
3694 conv3 = conditional_conversion (arg3, arg2);
3698 If both can be converted, or one can be converted but the
3699 conversion is ambiguous, the program is ill-formed. If
3700 neither can be converted, the operands are left unchanged and
3701 further checking is performed as described below. If exactly
3702 one conversion is possible, that conversion is applied to the
3703 chosen operand and the converted operand is used in place of
3704 the original operand for the remainder of this section. */
3705 if ((conv2 && !conv2->bad_p
3706 && conv3 && !conv3->bad_p)
3707 || (conv2 && conv2->kind == ck_ambig)
3708 || (conv3 && conv3->kind == ck_ambig))
3710 error ("operands to ?: have different types %qT and %qT",
3711 arg2_type, arg3_type);
3712 result = error_mark_node;
3714 else if (conv2 && (!conv2->bad_p || !conv3))
3716 arg2 = convert_like (conv2, arg2, complain);
3717 arg2 = convert_from_reference (arg2);
3718 arg2_type = TREE_TYPE (arg2);
3719 /* Even if CONV2 is a valid conversion, the result of the
3720 conversion may be invalid. For example, if ARG3 has type
3721 "volatile X", and X does not have a copy constructor
3722 accepting a "volatile X&", then even if ARG2 can be
3723 converted to X, the conversion will fail. */
3724 if (error_operand_p (arg2))
3725 result = error_mark_node;
3727 else if (conv3 && (!conv3->bad_p || !conv2))
3729 arg3 = convert_like (conv3, arg3, complain);
3730 arg3 = convert_from_reference (arg3);
3731 arg3_type = TREE_TYPE (arg3);
3732 if (error_operand_p (arg3))
3733 result = error_mark_node;
3736 /* Free all the conversions we allocated. */
3737 obstack_free (&conversion_obstack, p);
3742 /* If, after the conversion, both operands have class type,
3743 treat the cv-qualification of both operands as if it were the
3744 union of the cv-qualification of the operands.
3746 The standard is not clear about what to do in this
3747 circumstance. For example, if the first operand has type
3748 "const X" and the second operand has a user-defined
3749 conversion to "volatile X", what is the type of the second
3750 operand after this step? Making it be "const X" (matching
3751 the first operand) seems wrong, as that discards the
3752 qualification without actually performing a copy. Leaving it
3753 as "volatile X" seems wrong as that will result in the
3754 conditional expression failing altogether, even though,
3755 according to this step, the one operand could be converted to
3756 the type of the other. */
3757 if ((conv2 || conv3)
3758 && CLASS_TYPE_P (arg2_type)
3759 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3760 arg2_type = arg3_type =
3761 cp_build_qualified_type (arg2_type,
3762 TYPE_QUALS (arg2_type)
3763 | TYPE_QUALS (arg3_type));
3768 If the second and third operands are lvalues and have the same
3769 type, the result is of that type and is an lvalue. */
3770 if (real_lvalue_p (arg2)
3771 && real_lvalue_p (arg3)
3772 && same_type_p (arg2_type, arg3_type))
3774 result_type = arg2_type;
3775 goto valid_operands;
3780 Otherwise, the result is an rvalue. If the second and third
3781 operand do not have the same type, and either has (possibly
3782 cv-qualified) class type, overload resolution is used to
3783 determine the conversions (if any) to be applied to the operands
3784 (_over.match.oper_, _over.built_). */
3786 if (!same_type_p (arg2_type, arg3_type)
3787 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3793 /* Rearrange the arguments so that add_builtin_candidate only has
3794 to know about two args. In build_builtin_candidates, the
3795 arguments are unscrambled. */
3799 add_builtin_candidates (&candidates,
3802 ansi_opname (COND_EXPR),
3808 If the overload resolution fails, the program is
3810 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3813 if (complain & tf_error)
3815 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3816 print_z_candidates (candidates);
3818 return error_mark_node;
3820 cand = tourney (candidates);
3823 if (complain & tf_error)
3825 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3826 print_z_candidates (candidates);
3828 return error_mark_node;
3833 Otherwise, the conversions thus determined are applied, and
3834 the converted operands are used in place of the original
3835 operands for the remainder of this section. */
3836 conv = cand->convs[0];
3837 arg1 = convert_like (conv, arg1, complain);
3838 conv = cand->convs[1];
3839 arg2 = convert_like (conv, arg2, complain);
3840 conv = cand->convs[2];
3841 arg3 = convert_like (conv, arg3, complain);
3846 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3847 and function-to-pointer (_conv.func_) standard conversions are
3848 performed on the second and third operands.
3850 We need to force the lvalue-to-rvalue conversion here for class types,
3851 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3852 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3855 arg2 = force_rvalue (arg2);
3856 if (!CLASS_TYPE_P (arg2_type))
3857 arg2_type = TREE_TYPE (arg2);
3859 arg3 = force_rvalue (arg3);
3860 if (!CLASS_TYPE_P (arg2_type))
3861 arg3_type = TREE_TYPE (arg3);
3863 if (arg2 == error_mark_node || arg3 == error_mark_node)
3864 return error_mark_node;
3868 After those conversions, one of the following shall hold:
3870 --The second and third operands have the same type; the result is of
3872 if (same_type_p (arg2_type, arg3_type))
3873 result_type = arg2_type;
3876 --The second and third operands have arithmetic or enumeration
3877 type; the usual arithmetic conversions are performed to bring
3878 them to a common type, and the result is of that type. */
3879 else if ((ARITHMETIC_TYPE_P (arg2_type)
3880 || UNSCOPED_ENUM_P (arg2_type))
3881 && (ARITHMETIC_TYPE_P (arg3_type)
3882 || UNSCOPED_ENUM_P (arg3_type)))
3884 /* In this case, there is always a common type. */
3885 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3888 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3889 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3891 if (complain & tf_warning)
3893 "enumeral mismatch in conditional expression: %qT vs %qT",
3894 arg2_type, arg3_type);
3896 else if (extra_warnings
3897 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3898 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3899 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3900 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3902 if (complain & tf_warning)
3904 "enumeral and non-enumeral type in conditional expression");
3907 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3908 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3912 --The second and third operands have pointer type, or one has
3913 pointer type and the other is a null pointer constant; pointer
3914 conversions (_conv.ptr_) and qualification conversions
3915 (_conv.qual_) are performed to bring them to their composite
3916 pointer type (_expr.rel_). The result is of the composite
3919 --The second and third operands have pointer to member type, or
3920 one has pointer to member type and the other is a null pointer
3921 constant; pointer to member conversions (_conv.mem_) and
3922 qualification conversions (_conv.qual_) are performed to bring
3923 them to a common type, whose cv-qualification shall match the
3924 cv-qualification of either the second or the third operand.
3925 The result is of the common type. */
3926 else if ((null_ptr_cst_p (arg2)
3927 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3928 || (null_ptr_cst_p (arg3)
3929 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3930 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3931 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3932 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3934 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3935 arg3, "conditional expression",
3937 if (result_type == error_mark_node)
3938 return error_mark_node;
3939 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3940 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3945 if (complain & tf_error)
3946 error ("operands to ?: have different types %qT and %qT",
3947 arg2_type, arg3_type);
3948 return error_mark_node;
3952 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3954 /* We can't use result_type below, as fold might have returned a
3959 /* Expand both sides into the same slot, hopefully the target of
3960 the ?: expression. We used to check for TARGET_EXPRs here,
3961 but now we sometimes wrap them in NOP_EXPRs so the test would
3963 if (CLASS_TYPE_P (TREE_TYPE (result)))
3964 result = get_target_expr (result);
3965 /* If this expression is an rvalue, but might be mistaken for an
3966 lvalue, we must add a NON_LVALUE_EXPR. */
3967 result = rvalue (result);
3973 /* OPERAND is an operand to an expression. Perform necessary steps
3974 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3978 prep_operand (tree operand)
3982 if (CLASS_TYPE_P (TREE_TYPE (operand))
3983 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3984 /* Make sure the template type is instantiated now. */
3985 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3991 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3992 OVERLOAD) to the CANDIDATES, returning an updated list of
3993 CANDIDATES. The ARGS are the arguments provided to the call,
3994 without any implicit object parameter. This may change ARGS. The
3995 EXPLICIT_TARGS are explicit template arguments provided.
3996 TEMPLATE_ONLY is true if only template functions should be
3997 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
3998 add_function_candidate. */
4001 add_candidates (tree fns, const VEC(tree,gc) *args,
4002 tree explicit_targs, bool template_only,
4003 tree conversion_path, tree access_path,
4005 struct z_candidate **candidates)
4008 VEC(tree,gc) *non_static_args;
4011 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4012 /* Delay creating the implicit this parameter until it is needed. */
4013 non_static_args = NULL;
4014 first_arg = NULL_TREE;
4020 const VEC(tree,gc) *fn_args;
4022 fn = OVL_CURRENT (fns);
4023 /* Figure out which set of arguments to use. */
4024 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4026 /* If this function is a non-static member, prepend the implicit
4027 object parameter. */
4028 if (non_static_args == NULL)
4033 non_static_args = VEC_alloc (tree, gc,
4034 VEC_length (tree, args) - 1);
4035 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4036 VEC_quick_push (tree, non_static_args, arg);
4038 if (first_arg == NULL_TREE)
4039 first_arg = build_this (VEC_index (tree, args, 0));
4040 fn_first_arg = first_arg;
4041 fn_args = non_static_args;
4045 /* Otherwise, just use the list of arguments provided. */
4046 fn_first_arg = NULL_TREE;
4050 if (TREE_CODE (fn) == TEMPLATE_DECL)
4051 add_template_candidate (candidates,
4062 else if (!template_only)
4063 add_function_candidate (candidates,
4071 fns = OVL_NEXT (fns);
4075 /* Even unsigned enum types promote to signed int. We don't want to
4076 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4077 original argument and ARG is the argument after any conversions
4078 have been applied. We set TREE_NO_WARNING if we have added a cast
4079 from an unsigned enum type to a signed integer type. */
4082 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4084 if (orig_arg != NULL_TREE
4087 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4088 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4089 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4090 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4091 TREE_NO_WARNING (arg) = 1;
4095 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4096 bool *overloaded_p, tsubst_flags_t complain)
4098 tree orig_arg1 = arg1;
4099 tree orig_arg2 = arg2;
4100 tree orig_arg3 = arg3;
4101 struct z_candidate *candidates = 0, *cand;
4102 VEC(tree,gc) *arglist;
4105 tree result = NULL_TREE;
4106 bool result_valid_p = false;
4107 enum tree_code code2 = NOP_EXPR;
4108 enum tree_code code_orig_arg1 = ERROR_MARK;
4109 enum tree_code code_orig_arg2 = ERROR_MARK;
4115 if (error_operand_p (arg1)
4116 || error_operand_p (arg2)
4117 || error_operand_p (arg3))
4118 return error_mark_node;
4120 if (code == MODIFY_EXPR)
4122 code2 = TREE_CODE (arg3);
4124 fnname = ansi_assopname (code2);
4127 fnname = ansi_opname (code);
4129 arg1 = prep_operand (arg1);
4135 case VEC_DELETE_EXPR:
4137 /* Use build_op_new_call and build_op_delete_call instead. */
4141 /* Use build_op_call instead. */
4144 case TRUTH_ORIF_EXPR:
4145 case TRUTH_ANDIF_EXPR:
4146 case TRUTH_AND_EXPR:
4148 /* These are saved for the sake of warn_logical_operator. */
4149 code_orig_arg1 = TREE_CODE (arg1);
4150 code_orig_arg2 = TREE_CODE (arg2);
4156 arg2 = prep_operand (arg2);
4157 arg3 = prep_operand (arg3);
4159 if (code == COND_EXPR)
4161 if (arg2 == NULL_TREE
4162 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
4163 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
4164 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
4165 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
4168 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4169 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4172 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4173 arg2 = integer_zero_node;
4175 arglist = VEC_alloc (tree, gc, 3);
4176 VEC_quick_push (tree, arglist, arg1);
4177 if (arg2 != NULL_TREE)
4178 VEC_quick_push (tree, arglist, arg2);
4179 if (arg3 != NULL_TREE)
4180 VEC_quick_push (tree, arglist, arg3);
4182 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4183 p = conversion_obstack_alloc (0);
4185 /* Add namespace-scope operators to the list of functions to
4187 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4188 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4189 flags, &candidates);
4190 /* Add class-member operators to the candidate set. */
4191 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4195 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4196 if (fns == error_mark_node)
4198 result = error_mark_node;
4199 goto user_defined_result_ready;
4202 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4204 BASELINK_BINFO (fns),
4205 TYPE_BINFO (TREE_TYPE (arg1)),
4206 flags, &candidates);
4209 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
4210 to know about two args; a builtin candidate will always have a first
4211 parameter of type bool. We'll handle that in
4212 build_builtin_candidate. */
4213 if (code == COND_EXPR)
4223 args[2] = NULL_TREE;
4226 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4232 /* For these, the built-in candidates set is empty
4233 [over.match.oper]/3. We don't want non-strict matches
4234 because exact matches are always possible with built-in
4235 operators. The built-in candidate set for COMPONENT_REF
4236 would be empty too, but since there are no such built-in
4237 operators, we accept non-strict matches for them. */
4242 strict_p = pedantic;
4246 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4251 case POSTINCREMENT_EXPR:
4252 case POSTDECREMENT_EXPR:
4253 /* Don't try anything fancy if we're not allowed to produce
4255 if (!(complain & tf_error))
4256 return error_mark_node;
4258 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4259 distinguish between prefix and postfix ++ and
4260 operator++() was used for both, so we allow this with
4262 if (flags & LOOKUP_COMPLAIN)
4264 const char *msg = (flag_permissive)
4265 ? G_("no %<%D(int)%> declared for postfix %qs,"
4266 " trying prefix operator instead")
4267 : G_("no %<%D(int)%> declared for postfix %qs");
4268 permerror (input_location, msg, fnname,
4269 operator_name_info[code].name);
4272 if (!flag_permissive)
4273 return error_mark_node;
4275 if (code == POSTINCREMENT_EXPR)
4276 code = PREINCREMENT_EXPR;
4278 code = PREDECREMENT_EXPR;
4279 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4280 overloaded_p, complain);
4283 /* The caller will deal with these. */
4288 result_valid_p = true;
4292 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4294 /* If one of the arguments of the operator represents
4295 an invalid use of member function pointer, try to report
4296 a meaningful error ... */
4297 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4298 || invalid_nonstatic_memfn_p (arg2, tf_error)
4299 || invalid_nonstatic_memfn_p (arg3, tf_error))
4300 /* We displayed the error message. */;
4303 /* ... Otherwise, report the more generic
4304 "no matching operator found" error */
4305 op_error (code, code2, arg1, arg2, arg3, "no match");
4306 print_z_candidates (candidates);
4309 result = error_mark_node;
4315 cand = tourney (candidates);
4318 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4320 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4321 print_z_candidates (candidates);
4323 result = error_mark_node;
4325 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4328 *overloaded_p = true;
4330 if (resolve_args (arglist) == NULL)
4331 result = error_mark_node;
4333 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4337 /* Give any warnings we noticed during overload resolution. */
4338 if (cand->warnings && (complain & tf_warning))
4340 struct candidate_warning *w;
4341 for (w = cand->warnings; w; w = w->next)
4342 joust (cand, w->loser, 1);
4345 /* Check for comparison of different enum types. */
4354 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4355 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4356 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4357 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4358 && (complain & tf_warning))
4360 warning (OPT_Wenum_compare,
4361 "comparison between %q#T and %q#T",
4362 TREE_TYPE (arg1), TREE_TYPE (arg2));
4369 /* We need to strip any leading REF_BIND so that bitfields
4370 don't cause errors. This should not remove any important
4371 conversions, because builtins don't apply to class
4372 objects directly. */
4373 conv = cand->convs[0];
4374 if (conv->kind == ck_ref_bind)
4375 conv = conv->u.next;
4376 arg1 = convert_like (conv, arg1, complain);
4380 /* We need to call warn_logical_operator before
4381 converting arg2 to a boolean_type. */
4382 if (complain & tf_warning)
4383 warn_logical_operator (input_location, code, boolean_type_node,
4384 code_orig_arg1, arg1,
4385 code_orig_arg2, arg2);
4387 conv = cand->convs[1];
4388 if (conv->kind == ck_ref_bind)
4389 conv = conv->u.next;
4390 arg2 = convert_like (conv, arg2, complain);
4394 conv = cand->convs[2];
4395 if (conv->kind == ck_ref_bind)
4396 conv = conv->u.next;
4397 arg3 = convert_like (conv, arg3, complain);
4403 user_defined_result_ready:
4405 /* Free all the conversions we allocated. */
4406 obstack_free (&conversion_obstack, p);
4408 if (result || result_valid_p)
4412 avoid_sign_compare_warnings (orig_arg1, arg1);
4413 avoid_sign_compare_warnings (orig_arg2, arg2);
4414 avoid_sign_compare_warnings (orig_arg3, arg3);
4419 return cp_build_modify_expr (arg1, code2, arg2, complain);
4422 return cp_build_indirect_ref (arg1, "unary *", complain);
4424 case TRUTH_ANDIF_EXPR:
4425 case TRUTH_ORIF_EXPR:
4426 case TRUTH_AND_EXPR:
4428 warn_logical_operator (input_location, code, boolean_type_node,
4429 code_orig_arg1, arg1, code_orig_arg2, arg2);
4434 case TRUNC_DIV_EXPR:
4445 case TRUNC_MOD_EXPR:
4449 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4451 case UNARY_PLUS_EXPR:
4454 case TRUTH_NOT_EXPR:
4455 case PREINCREMENT_EXPR:
4456 case POSTINCREMENT_EXPR:
4457 case PREDECREMENT_EXPR:
4458 case POSTDECREMENT_EXPR:
4461 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4464 return build_array_ref (input_location, arg1, arg2);
4467 return build_conditional_expr (arg1, arg2, arg3, complain);
4470 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4474 /* The caller will deal with these. */
4486 /* Build a call to operator delete. This has to be handled very specially,
4487 because the restrictions on what signatures match are different from all
4488 other call instances. For a normal delete, only a delete taking (void *)
4489 or (void *, size_t) is accepted. For a placement delete, only an exact
4490 match with the placement new is accepted.
4492 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4493 ADDR is the pointer to be deleted.
4494 SIZE is the size of the memory block to be deleted.
4495 GLOBAL_P is true if the delete-expression should not consider
4496 class-specific delete operators.
4497 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4499 If this call to "operator delete" is being generated as part to
4500 deallocate memory allocated via a new-expression (as per [expr.new]
4501 which requires that if the initialization throws an exception then
4502 we call a deallocation function), then ALLOC_FN is the allocation
4506 build_op_delete_call (enum tree_code code, tree addr, tree size,
4507 bool global_p, tree placement,
4510 tree fn = NULL_TREE;
4511 tree fns, fnname, argtypes, type;
4514 if (addr == error_mark_node)
4515 return error_mark_node;
4517 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4519 fnname = ansi_opname (code);
4521 if (CLASS_TYPE_P (type)
4522 && COMPLETE_TYPE_P (complete_type (type))
4526 If the result of the lookup is ambiguous or inaccessible, or if
4527 the lookup selects a placement deallocation function, the
4528 program is ill-formed.
4530 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4532 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4533 if (fns == error_mark_node)
4534 return error_mark_node;
4539 if (fns == NULL_TREE)
4540 fns = lookup_name_nonclass (fnname);
4542 /* Strip const and volatile from addr. */
4543 addr = cp_convert (ptr_type_node, addr);
4547 /* Get the parameter types for the allocation function that is
4549 gcc_assert (alloc_fn != NULL_TREE);
4550 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4554 /* First try it without the size argument. */
4555 argtypes = void_list_node;
4558 /* We make two tries at finding a matching `operator delete'. On
4559 the first pass, we look for a one-operator (or placement)
4560 operator delete. If we're not doing placement delete, then on
4561 the second pass we look for a two-argument delete. */
4562 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4564 /* Go through the `operator delete' functions looking for one
4565 with a matching type. */
4566 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4572 /* The first argument must be "void *". */
4573 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4574 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4577 /* On the first pass, check the rest of the arguments. */
4583 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4591 /* On the second pass, look for a function with exactly two
4592 arguments: "void *" and "size_t". */
4594 /* For "operator delete(void *, ...)" there will be
4595 no second argument, but we will not get an exact
4598 && same_type_p (TREE_VALUE (t), size_type_node)
4599 && TREE_CHAIN (t) == void_list_node)
4603 /* If we found a match, we're done. */
4608 /* If we have a matching function, call it. */
4611 /* Make sure we have the actual function, and not an
4613 fn = OVL_CURRENT (fn);
4615 /* If the FN is a member function, make sure that it is
4617 if (DECL_CLASS_SCOPE_P (fn))
4618 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4620 /* Core issue 901: It's ok to new a type with deleted delete. */
4621 if (DECL_DELETED_FN (fn) && alloc_fn)
4626 /* The placement args might not be suitable for overload
4627 resolution at this point, so build the call directly. */
4628 int nargs = call_expr_nargs (placement);
4629 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4632 for (i = 1; i < nargs; i++)
4633 argarray[i] = CALL_EXPR_ARG (placement, i);
4635 return build_cxx_call (fn, nargs, argarray);
4640 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4641 VEC_quick_push (tree, args, addr);
4643 VEC_quick_push (tree, args, size);
4644 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4645 VEC_free (tree, gc, args);
4652 If no unambiguous matching deallocation function can be found,
4653 propagating the exception does not cause the object's memory to
4658 warning (0, "no corresponding deallocation function for %qD",
4663 error ("no suitable %<operator %s%> for %qT",
4664 operator_name_info[(int)code].name, type);
4665 return error_mark_node;
4668 /* If the current scope isn't allowed to access DECL along
4669 BASETYPE_PATH, give an error. The most derived class in
4670 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4671 the declaration to use in the error diagnostic. */
4674 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4676 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4678 if (!accessible_p (basetype_path, decl, true))
4680 if (TREE_PRIVATE (decl))
4681 error ("%q+#D is private", diag_decl);
4682 else if (TREE_PROTECTED (decl))
4683 error ("%q+#D is protected", diag_decl);
4685 error ("%q+#D is inaccessible", diag_decl);
4686 error ("within this context");
4693 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4694 bitwise or of LOOKUP_* values. If any errors are warnings are
4695 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4696 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4700 build_temp (tree expr, tree type, int flags,
4701 diagnostic_t *diagnostic_kind)
4706 savew = warningcount, savee = errorcount;
4707 args = make_tree_vector_single (expr);
4708 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4709 &args, type, flags, tf_warning_or_error);
4710 release_tree_vector (args);
4711 if (warningcount > savew)
4712 *diagnostic_kind = DK_WARNING;
4713 else if (errorcount > savee)
4714 *diagnostic_kind = DK_ERROR;
4716 *diagnostic_kind = DK_UNSPECIFIED;
4720 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4721 EXPR is implicitly converted to type TOTYPE.
4722 FN and ARGNUM are used for diagnostics. */
4725 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4727 tree t = non_reference (totype);
4729 /* Issue warnings about peculiar, but valid, uses of NULL. */
4730 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4733 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4736 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4739 /* Issue warnings if "false" is converted to a NULL pointer */
4740 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4741 warning (OPT_Wconversion,
4742 "converting %<false%> to pointer type for argument %P of %qD",
4746 /* Perform the conversions in CONVS on the expression EXPR. FN and
4747 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4748 indicates the `this' argument of a method. INNER is nonzero when
4749 being called to continue a conversion chain. It is negative when a
4750 reference binding will be applied, positive otherwise. If
4751 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4752 conversions will be emitted if appropriate. If C_CAST_P is true,
4753 this conversion is coming from a C-style cast; in that case,
4754 conversions to inaccessible bases are permitted. */
4757 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4758 int inner, bool issue_conversion_warnings,
4759 bool c_cast_p, tsubst_flags_t complain)
4761 tree totype = convs->type;
4762 diagnostic_t diag_kind;
4766 && convs->kind != ck_user
4767 && convs->kind != ck_list
4768 && convs->kind != ck_ambig
4769 && convs->kind != ck_ref_bind
4770 && convs->kind != ck_rvalue
4771 && convs->kind != ck_base)
4773 conversion *t = convs;
4775 /* Give a helpful error if this is bad because of excess braces. */
4776 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4777 && SCALAR_TYPE_P (totype)
4778 && CONSTRUCTOR_NELTS (expr) > 0
4779 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4780 permerror (input_location, "too many braces around initializer for %qT", totype);
4782 for (; t; t = convs->u.next)
4784 if (t->kind == ck_user || !t->bad_p)
4786 expr = convert_like_real (t, expr, fn, argnum, 1,
4787 /*issue_conversion_warnings=*/false,
4792 else if (t->kind == ck_ambig)
4793 return convert_like_real (t, expr, fn, argnum, 1,
4794 /*issue_conversion_warnings=*/false,
4797 else if (t->kind == ck_identity)
4800 if (complain & tf_error)
4802 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4804 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4807 return error_mark_node;
4809 return cp_convert (totype, expr);
4812 if (issue_conversion_warnings && (complain & tf_warning))
4813 conversion_null_warnings (totype, expr, fn, argnum);
4815 switch (convs->kind)
4819 struct z_candidate *cand = convs->cand;
4820 tree convfn = cand->fn;
4823 /* When converting from an init list we consider explicit
4824 constructors, but actually trying to call one is an error. */
4825 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4827 if (complain & tf_error)
4828 error ("converting to %qT from initializer list would use "
4829 "explicit constructor %qD", totype, convfn);
4831 return error_mark_node;
4834 /* Set user_conv_p on the argument conversions, so rvalue/base
4835 handling knows not to allow any more UDCs. */
4836 for (i = 0; i < cand->num_convs; ++i)
4837 cand->convs[i]->user_conv_p = true;
4839 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4841 /* If this is a constructor or a function returning an aggr type,
4842 we need to build up a TARGET_EXPR. */
4843 if (DECL_CONSTRUCTOR_P (convfn))
4845 expr = build_cplus_new (totype, expr);
4847 /* Remember that this was list-initialization. */
4848 if (convs->check_narrowing)
4849 TARGET_EXPR_LIST_INIT_P (expr) = true;
4855 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4857 int nelts = CONSTRUCTOR_NELTS (expr);
4859 expr = integer_zero_node;
4860 else if (nelts == 1)
4861 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4866 if (type_unknown_p (expr))
4867 expr = instantiate_type (totype, expr, complain);
4868 /* Convert a constant to its underlying value, unless we are
4869 about to bind it to a reference, in which case we need to
4870 leave it as an lvalue. */
4873 expr = decl_constant_value (expr);
4874 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4875 /* If __null has been converted to an integer type, we do not
4876 want to warn about uses of EXPR as an integer, rather than
4878 expr = build_int_cst (totype, 0);
4882 /* Call build_user_type_conversion again for the error. */
4883 return build_user_type_conversion
4884 (totype, convs->u.expr, LOOKUP_NORMAL);
4888 /* Conversion to std::initializer_list<T>. */
4889 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4890 tree new_ctor = build_constructor (init_list_type_node, NULL);
4891 unsigned len = CONSTRUCTOR_NELTS (expr);
4893 VEC(tree,gc) *parms;
4896 /* Convert all the elements. */
4897 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4899 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4900 1, false, false, complain);
4901 if (sub == error_mark_node)
4903 check_narrowing (TREE_TYPE (sub), val);
4904 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4906 /* Build up the array. */
4907 elttype = cp_build_qualified_type
4908 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4909 array = build_array_of_n_type (elttype, len);
4910 array = finish_compound_literal (array, new_ctor);
4912 parms = make_tree_vector ();
4913 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4914 VEC_safe_push (tree, gc, parms, size_int (len));
4915 /* Call the private constructor. */
4916 push_deferring_access_checks (dk_no_check);
4917 new_ctor = build_special_member_call
4918 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4919 release_tree_vector (parms);
4920 pop_deferring_access_checks ();
4921 return build_cplus_new (totype, new_ctor);
4925 return get_target_expr (digest_init (totype, expr));
4931 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4932 convs->kind == ck_ref_bind ? -1 : 1,
4933 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4936 if (expr == error_mark_node)
4937 return error_mark_node;
4939 switch (convs->kind)
4942 expr = convert_bitfield_to_declared_type (expr);
4943 if (! MAYBE_CLASS_TYPE_P (totype))
4945 /* Else fall through. */
4947 if (convs->kind == ck_base && !convs->need_temporary_p)
4949 /* We are going to bind a reference directly to a base-class
4950 subobject of EXPR. */
4951 /* Build an expression for `*((base*) &expr)'. */
4952 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4953 expr = convert_to_base (expr, build_pointer_type (totype),
4954 !c_cast_p, /*nonnull=*/true);
4955 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4959 /* Copy-initialization where the cv-unqualified version of the source
4960 type is the same class as, or a derived class of, the class of the
4961 destination [is treated as direct-initialization]. [dcl.init] */
4962 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4963 if (convs->user_conv_p)
4964 /* This conversion is being done in the context of a user-defined
4965 conversion (i.e. the second step of copy-initialization), so
4966 don't allow any more. */
4967 flags |= LOOKUP_NO_CONVERSION;
4968 expr = build_temp (expr, totype, flags, &diag_kind);
4969 if (diag_kind && fn)
4971 if ((complain & tf_error))
4972 emit_diagnostic (diag_kind, input_location, 0,
4973 " initializing argument %P of %qD", argnum, fn);
4974 else if (diag_kind == DK_ERROR)
4975 return error_mark_node;
4977 return build_cplus_new (totype, expr);
4981 tree ref_type = totype;
4983 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
4984 && real_lvalue_p (expr))
4986 if (complain & tf_error)
4988 error ("cannot bind %qT lvalue to %qT",
4989 TREE_TYPE (expr), totype);
4991 error (" initializing argument %P of %q+D", argnum, fn);
4993 return error_mark_node;
4996 /* If necessary, create a temporary.
4998 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4999 that need temporaries, even when their types are reference
5000 compatible with the type of reference being bound, so the
5001 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5003 if (convs->need_temporary_p
5004 || TREE_CODE (expr) == CONSTRUCTOR
5005 || TREE_CODE (expr) == VA_ARG_EXPR)
5007 tree type = convs->u.next->type;
5008 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5010 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
5011 && !TYPE_REF_IS_RVALUE (ref_type))
5013 if (complain & tf_error)
5015 /* If the reference is volatile or non-const, we
5016 cannot create a temporary. */
5017 if (lvalue & clk_bitfield)
5018 error ("cannot bind bitfield %qE to %qT",
5020 else if (lvalue & clk_packed)
5021 error ("cannot bind packed field %qE to %qT",
5024 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5026 return error_mark_node;
5028 /* If the source is a packed field, and we must use a copy
5029 constructor, then building the target expr will require
5030 binding the field to the reference parameter to the
5031 copy constructor, and we'll end up with an infinite
5032 loop. If we can use a bitwise copy, then we'll be
5034 if ((lvalue & clk_packed)
5035 && CLASS_TYPE_P (type)
5036 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
5038 if (complain & tf_error)
5039 error ("cannot bind packed field %qE to %qT",
5041 return error_mark_node;
5043 if (lvalue & clk_bitfield)
5045 expr = convert_bitfield_to_declared_type (expr);
5046 expr = fold_convert (type, expr);
5048 expr = build_target_expr_with_type (expr, type);
5051 /* Take the address of the thing to which we will bind the
5053 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5054 if (expr == error_mark_node)
5055 return error_mark_node;
5057 /* Convert it to a pointer to the type referred to by the
5058 reference. This will adjust the pointer if a derived to
5059 base conversion is being performed. */
5060 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5062 /* Convert the pointer to the desired reference type. */
5063 return build_nop (ref_type, expr);
5067 return decay_conversion (expr);
5070 /* Warn about deprecated conversion if appropriate. */
5071 string_conv_p (totype, expr, 1);
5076 expr = convert_to_base (expr, totype, !c_cast_p,
5078 return build_nop (totype, expr);
5081 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5088 if (convs->check_narrowing)
5089 check_narrowing (totype, expr);
5091 if (issue_conversion_warnings && (complain & tf_warning))
5092 expr = convert_and_check (totype, expr);
5094 expr = convert (totype, expr);
5099 /* ARG is being passed to a varargs function. Perform any conversions
5100 required. Return the converted value. */
5103 convert_arg_to_ellipsis (tree arg)
5107 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5108 standard conversions are performed. */
5109 arg = decay_conversion (arg);
5112 If the argument has integral or enumeration type that is subject
5113 to the integral promotions (_conv.prom_), or a floating point
5114 type that is subject to the floating point promotion
5115 (_conv.fpprom_), the value of the argument is converted to the
5116 promoted type before the call. */
5117 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5118 && (TYPE_PRECISION (TREE_TYPE (arg))
5119 < TYPE_PRECISION (double_type_node)))
5120 arg = convert_to_real (double_type_node, arg);
5121 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5122 arg = perform_integral_promotions (arg);
5124 arg = require_complete_type (arg);
5126 if (arg != error_mark_node
5127 && (type_has_nontrivial_copy_init (TREE_TYPE (arg))
5128 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (arg))))
5130 /* [expr.call] 5.2.2/7:
5131 Passing a potentially-evaluated argument of class type (Clause 9)
5132 with a non-trivial copy constructor or a non-trivial destructor
5133 with no corresponding parameter is conditionally-supported, with
5134 implementation-defined semantics.
5136 We used to just warn here and do a bitwise copy, but now
5137 cp_expr_size will abort if we try to do that.
5139 If the call appears in the context of a sizeof expression,
5140 it is not potentially-evaluated. */
5141 if (cp_unevaluated_operand == 0)
5142 error ("cannot pass objects of non-trivially-copyable "
5143 "type %q#T through %<...%>", TREE_TYPE (arg));
5149 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5152 build_x_va_arg (tree expr, tree type)
5154 if (processing_template_decl)
5155 return build_min (VA_ARG_EXPR, type, expr);
5157 type = complete_type_or_else (type, NULL_TREE);
5159 if (expr == error_mark_node || !type)
5160 return error_mark_node;
5162 if (type_has_nontrivial_copy_init (type)
5163 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5164 || TREE_CODE (type) == REFERENCE_TYPE)
5166 /* Remove reference types so we don't ICE later on. */
5167 tree type1 = non_reference (type);
5168 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5169 error ("cannot receive objects of non-trivially-copyable type %q#T "
5170 "through %<...%>; ", type);
5171 expr = convert (build_pointer_type (type1), null_node);
5172 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
5176 return build_va_arg (input_location, expr, type);
5179 /* TYPE has been given to va_arg. Apply the default conversions which
5180 would have happened when passed via ellipsis. Return the promoted
5181 type, or the passed type if there is no change. */
5184 cxx_type_promotes_to (tree type)
5188 /* Perform the array-to-pointer and function-to-pointer
5190 type = type_decays_to (type);
5192 promote = type_promotes_to (type);
5193 if (same_type_p (type, promote))
5199 /* ARG is a default argument expression being passed to a parameter of
5200 the indicated TYPE, which is a parameter to FN. Do any required
5201 conversions. Return the converted value. */
5203 static GTY(()) VEC(tree,gc) *default_arg_context;
5206 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5211 /* If the ARG is an unparsed default argument expression, the
5212 conversion cannot be performed. */
5213 if (TREE_CODE (arg) == DEFAULT_ARG)
5215 error ("the default argument for parameter %d of %qD has "
5216 "not yet been parsed",
5218 return error_mark_node;
5221 /* Detect recursion. */
5222 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5225 error ("recursive evaluation of default argument for %q#D", fn);
5226 return error_mark_node;
5228 VEC_safe_push (tree, gc, default_arg_context, fn);
5230 if (fn && DECL_TEMPLATE_INFO (fn))
5231 arg = tsubst_default_argument (fn, type, arg);
5237 The names in the expression are bound, and the semantic
5238 constraints are checked, at the point where the default
5239 expressions appears.
5241 we must not perform access checks here. */
5242 push_deferring_access_checks (dk_no_check);
5243 arg = break_out_target_exprs (arg);
5244 if (TREE_CODE (arg) == CONSTRUCTOR)
5246 arg = digest_init (type, arg);
5247 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5248 "default argument", fn, parmnum,
5249 tf_warning_or_error);
5253 /* We must make a copy of ARG, in case subsequent processing
5254 alters any part of it. For example, during gimplification a
5255 cast of the form (T) &X::f (where "f" is a member function)
5256 will lead to replacing the PTRMEM_CST for &X::f with a
5257 VAR_DECL. We can avoid the copy for constants, since they
5258 are never modified in place. */
5259 if (!CONSTANT_CLASS_P (arg))
5260 arg = unshare_expr (arg);
5261 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5262 "default argument", fn, parmnum,
5263 tf_warning_or_error);
5264 arg = convert_for_arg_passing (type, arg);
5266 pop_deferring_access_checks();
5268 VEC_pop (tree, default_arg_context);
5273 /* Returns the type which will really be used for passing an argument of
5277 type_passed_as (tree type)
5279 /* Pass classes with copy ctors by invisible reference. */
5280 if (TREE_ADDRESSABLE (type))
5282 type = build_reference_type (type);
5283 /* There are no other pointers to this temporary. */
5284 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5286 else if (targetm.calls.promote_prototypes (type)
5287 && INTEGRAL_TYPE_P (type)
5288 && COMPLETE_TYPE_P (type)
5289 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5290 TYPE_SIZE (integer_type_node)))
5291 type = integer_type_node;
5296 /* Actually perform the appropriate conversion. */
5299 convert_for_arg_passing (tree type, tree val)
5303 /* If VAL is a bitfield, then -- since it has already been converted
5304 to TYPE -- it cannot have a precision greater than TYPE.
5306 If it has a smaller precision, we must widen it here. For
5307 example, passing "int f:3;" to a function expecting an "int" will
5308 not result in any conversion before this point.
5310 If the precision is the same we must not risk widening. For
5311 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5312 often have type "int", even though the C++ type for the field is
5313 "long long". If the value is being passed to a function
5314 expecting an "int", then no conversions will be required. But,
5315 if we call convert_bitfield_to_declared_type, the bitfield will
5316 be converted to "long long". */
5317 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5319 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5320 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5322 if (val == error_mark_node)
5324 /* Pass classes with copy ctors by invisible reference. */
5325 else if (TREE_ADDRESSABLE (type))
5326 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5327 else if (targetm.calls.promote_prototypes (type)
5328 && INTEGRAL_TYPE_P (type)
5329 && COMPLETE_TYPE_P (type)
5330 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5331 TYPE_SIZE (integer_type_node)))
5332 val = perform_integral_promotions (val);
5333 if (warn_missing_format_attribute)
5335 tree rhstype = TREE_TYPE (val);
5336 const enum tree_code coder = TREE_CODE (rhstype);
5337 const enum tree_code codel = TREE_CODE (type);
5338 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5340 && check_missing_format_attribute (type, rhstype))
5341 warning (OPT_Wmissing_format_attribute,
5342 "argument of function call might be a candidate for a format attribute");
5347 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5348 which no conversions at all should be done. This is true for some
5349 builtins which don't act like normal functions. */
5352 magic_varargs_p (tree fn)
5354 if (DECL_BUILT_IN (fn))
5355 switch (DECL_FUNCTION_CODE (fn))
5357 case BUILT_IN_CLASSIFY_TYPE:
5358 case BUILT_IN_CONSTANT_P:
5359 case BUILT_IN_NEXT_ARG:
5360 case BUILT_IN_VA_START:
5364 return lookup_attribute ("type generic",
5365 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5371 /* Subroutine of the various build_*_call functions. Overload resolution
5372 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5373 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5374 bitmask of various LOOKUP_* flags which apply to the call itself. */
5377 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5380 const VEC(tree,gc) *args = cand->args;
5381 tree first_arg = cand->first_arg;
5382 conversion **convs = cand->convs;
5384 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5389 unsigned int arg_index = 0;
5393 bool already_used = false;
5395 /* In a template, there is no need to perform all of the work that
5396 is normally done. We are only interested in the type of the call
5397 expression, i.e., the return type of the function. Any semantic
5398 errors will be deferred until the template is instantiated. */
5399 if (processing_template_decl)
5403 const tree *argarray;
5406 return_type = TREE_TYPE (TREE_TYPE (fn));
5407 nargs = VEC_length (tree, args);
5408 if (first_arg == NULL_TREE)
5409 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5417 alcarray = XALLOCAVEC (tree, nargs);
5418 alcarray[0] = first_arg;
5419 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5420 alcarray[ix + 1] = arg;
5421 argarray = alcarray;
5423 expr = build_call_array_loc (input_location,
5424 return_type, build_addr_func (fn), nargs,
5426 if (TREE_THIS_VOLATILE (fn) && cfun)
5427 current_function_returns_abnormally = 1;
5428 if (!VOID_TYPE_P (return_type))
5429 require_complete_type (return_type);
5430 return convert_from_reference (expr);
5433 /* Give any warnings we noticed during overload resolution. */
5436 struct candidate_warning *w;
5437 for (w = cand->warnings; w; w = w->next)
5438 joust (cand, w->loser, 1);
5441 /* Make =delete work with SFINAE. */
5442 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5443 return error_mark_node;
5445 if (DECL_FUNCTION_MEMBER_P (fn))
5447 /* If FN is a template function, two cases must be considered.
5452 template <class T> void f();
5454 template <class T> struct B {
5458 struct C : A, B<int> {
5460 using B<int>::g; // #2
5463 In case #1 where `A::f' is a member template, DECL_ACCESS is
5464 recorded in the primary template but not in its specialization.
5465 We check access of FN using its primary template.
5467 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5468 because it is a member of class template B, DECL_ACCESS is
5469 recorded in the specialization `B<int>::g'. We cannot use its
5470 primary template because `B<T>::g' and `B<int>::g' may have
5471 different access. */
5472 if (DECL_TEMPLATE_INFO (fn)
5473 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5474 perform_or_defer_access_check (cand->access_path,
5475 DECL_TI_TEMPLATE (fn), fn);
5477 perform_or_defer_access_check (cand->access_path, fn, fn);
5480 /* Find maximum size of vector to hold converted arguments. */
5481 parmlen = list_length (parm);
5482 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5483 if (parmlen > nargs)
5485 argarray = (tree *) alloca (nargs * sizeof (tree));
5487 /* The implicit parameters to a constructor are not considered by overload
5488 resolution, and must be of the proper type. */
5489 if (DECL_CONSTRUCTOR_P (fn))
5491 if (first_arg != NULL_TREE)
5493 argarray[j++] = first_arg;
5494 first_arg = NULL_TREE;
5498 argarray[j++] = VEC_index (tree, args, arg_index);
5501 parm = TREE_CHAIN (parm);
5502 /* We should never try to call the abstract constructor. */
5503 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5505 if (DECL_HAS_VTT_PARM_P (fn))
5507 argarray[j++] = VEC_index (tree, args, arg_index);
5509 parm = TREE_CHAIN (parm);
5512 /* Bypass access control for 'this' parameter. */
5513 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5515 tree parmtype = TREE_VALUE (parm);
5516 tree arg = (first_arg != NULL_TREE
5518 : VEC_index (tree, args, arg_index));
5519 tree argtype = TREE_TYPE (arg);
5523 if (convs[i]->bad_p)
5525 if (complain & tf_error)
5526 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5527 TREE_TYPE (argtype), fn);
5529 return error_mark_node;
5532 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5533 X is called for an object that is not of type X, or of a type
5534 derived from X, the behavior is undefined.
5536 So we can assume that anything passed as 'this' is non-null, and
5537 optimize accordingly. */
5538 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5539 /* Convert to the base in which the function was declared. */
5540 gcc_assert (cand->conversion_path != NULL_TREE);
5541 converted_arg = build_base_path (PLUS_EXPR,
5543 cand->conversion_path,
5545 /* Check that the base class is accessible. */
5546 if (!accessible_base_p (TREE_TYPE (argtype),
5547 BINFO_TYPE (cand->conversion_path), true))
5548 error ("%qT is not an accessible base of %qT",
5549 BINFO_TYPE (cand->conversion_path),
5550 TREE_TYPE (argtype));
5551 /* If fn was found by a using declaration, the conversion path
5552 will be to the derived class, not the base declaring fn. We
5553 must convert from derived to base. */
5554 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5555 TREE_TYPE (parmtype), ba_unique, NULL);
5556 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5559 argarray[j++] = converted_arg;
5560 parm = TREE_CHAIN (parm);
5561 if (first_arg != NULL_TREE)
5562 first_arg = NULL_TREE;
5569 gcc_assert (first_arg == NULL_TREE);
5570 for (; arg_index < VEC_length (tree, args) && parm;
5571 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5573 tree type = TREE_VALUE (parm);
5577 /* Don't make a copy here if build_call is going to. */
5578 if (conv->kind == ck_rvalue
5579 && COMPLETE_TYPE_P (complete_type (type))
5580 && !TREE_ADDRESSABLE (type))
5581 conv = conv->u.next;
5583 val = convert_like_with_context
5584 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5587 val = convert_for_arg_passing (type, val);
5588 if (val == error_mark_node)
5589 return error_mark_node;
5591 argarray[j++] = val;
5594 /* Default arguments */
5595 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5596 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5597 TREE_PURPOSE (parm),
5600 for (; arg_index < VEC_length (tree, args); ++arg_index)
5602 tree a = VEC_index (tree, args, arg_index);
5603 if (magic_varargs_p (fn))
5604 /* Do no conversions for magic varargs. */;
5606 a = convert_arg_to_ellipsis (a);
5610 gcc_assert (j <= nargs);
5613 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5614 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5616 /* Avoid actually calling copy constructors and copy assignment operators,
5619 if (! flag_elide_constructors)
5620 /* Do things the hard way. */;
5621 else if (cand->num_convs == 1
5622 && (DECL_COPY_CONSTRUCTOR_P (fn)
5623 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5626 tree arg = argarray[num_artificial_parms_for (fn)];
5629 /* Pull out the real argument, disregarding const-correctness. */
5631 while (CONVERT_EXPR_P (targ)
5632 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5633 targ = TREE_OPERAND (targ, 0);
5634 if (TREE_CODE (targ) == ADDR_EXPR)
5636 targ = TREE_OPERAND (targ, 0);
5637 if (!same_type_ignoring_top_level_qualifiers_p
5638 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5647 arg = cp_build_indirect_ref (arg, 0, complain);
5649 if (TREE_CODE (arg) == TARGET_EXPR
5650 && TARGET_EXPR_LIST_INIT_P (arg))
5652 /* Copy-list-initialization doesn't require the copy constructor
5655 /* [class.copy]: the copy constructor is implicitly defined even if
5656 the implementation elided its use. */
5657 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5660 already_used = true;
5663 /* If we're creating a temp and we already have one, don't create a
5664 new one. If we're not creating a temp but we get one, use
5665 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5666 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5667 temp or an INIT_EXPR otherwise. */
5668 fa = (cand->first_arg != NULL_TREE
5670 : VEC_index (tree, args, 0));
5671 if (integer_zerop (fa))
5673 if (TREE_CODE (arg) == TARGET_EXPR)
5675 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5676 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5678 else if (TREE_CODE (arg) == TARGET_EXPR
5679 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5680 && !move_fn_p (fn)))
5682 tree to = stabilize_reference (cp_build_indirect_ref (fa, 0,
5685 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5689 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5691 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5693 tree to = stabilize_reference
5694 (cp_build_indirect_ref (argarray[0], 0, complain));
5695 tree type = TREE_TYPE (to);
5696 tree as_base = CLASSTYPE_AS_BASE (type);
5697 tree arg = argarray[1];
5699 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5701 arg = cp_build_indirect_ref (arg, 0, complain);
5702 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5706 /* We must only copy the non-tail padding parts.
5707 Use __builtin_memcpy for the bitwise copy.
5708 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5709 instead of an explicit call to memcpy. */
5711 tree arg0, arg1, arg2, t;
5712 tree test = NULL_TREE;
5714 arg2 = TYPE_SIZE_UNIT (as_base);
5716 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5718 if (!can_trust_pointer_alignment ())
5720 /* If we can't be sure about pointer alignment, a call
5721 to __builtin_memcpy is expanded as a call to memcpy, which
5722 is invalid with identical args. Otherwise it is
5723 expanded as a block move, which should be safe. */
5724 arg0 = save_expr (arg0);
5725 arg1 = save_expr (arg1);
5726 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5728 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5729 t = build_call_n (t, 3, arg0, arg1, arg2);
5731 t = convert (TREE_TYPE (arg0), t);
5733 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5734 val = cp_build_indirect_ref (t, 0, complain);
5735 TREE_NO_WARNING (val) = 1;
5744 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5747 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5750 gcc_assert (binfo && binfo != error_mark_node);
5752 /* Warn about deprecated virtual functions now, since we're about
5753 to throw away the decl. */
5754 if (TREE_DEPRECATED (fn))
5755 warn_deprecated_use (fn, NULL_TREE);
5757 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5758 if (TREE_SIDE_EFFECTS (argarray[0]))
5759 argarray[0] = save_expr (argarray[0]);
5760 t = build_pointer_type (TREE_TYPE (fn));
5761 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5762 fn = build_java_interface_fn_ref (fn, argarray[0]);
5764 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5768 fn = build_addr_func (fn);
5770 return build_cxx_call (fn, nargs, argarray);
5773 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5774 This function performs no overload resolution, conversion, or other
5775 high-level operations. */
5778 build_cxx_call (tree fn, int nargs, tree *argarray)
5782 fn = build_call_a (fn, nargs, argarray);
5784 /* If this call might throw an exception, note that fact. */
5785 fndecl = get_callee_fndecl (fn);
5786 if ((!fndecl || !TREE_NOTHROW (fndecl))
5787 && at_function_scope_p ()
5789 cp_function_chain->can_throw = 1;
5791 /* Check that arguments to builtin functions match the expectations. */
5793 && DECL_BUILT_IN (fndecl)
5794 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5795 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5796 return error_mark_node;
5798 /* Some built-in function calls will be evaluated at compile-time in
5800 fn = fold_if_not_in_template (fn);
5802 if (VOID_TYPE_P (TREE_TYPE (fn)))
5805 fn = require_complete_type (fn);
5806 if (fn == error_mark_node)
5807 return error_mark_node;
5809 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5810 fn = build_cplus_new (TREE_TYPE (fn), fn);
5811 return convert_from_reference (fn);
5814 static GTY(()) tree java_iface_lookup_fn;
5816 /* Make an expression which yields the address of the Java interface
5817 method FN. This is achieved by generating a call to libjava's
5818 _Jv_LookupInterfaceMethodIdx(). */
5821 build_java_interface_fn_ref (tree fn, tree instance)
5823 tree lookup_fn, method, idx;
5824 tree klass_ref, iface, iface_ref;
5827 if (!java_iface_lookup_fn)
5829 tree endlink = build_void_list_node ();
5830 tree t = tree_cons (NULL_TREE, ptr_type_node,
5831 tree_cons (NULL_TREE, ptr_type_node,
5832 tree_cons (NULL_TREE, java_int_type_node,
5834 java_iface_lookup_fn
5835 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5836 build_function_type (ptr_type_node, t),
5837 0, NOT_BUILT_IN, NULL, NULL_TREE);
5840 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5841 This is the first entry in the vtable. */
5842 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5843 tf_warning_or_error),
5846 /* Get the java.lang.Class pointer for the interface being called. */
5847 iface = DECL_CONTEXT (fn);
5848 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5849 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5850 || DECL_CONTEXT (iface_ref) != iface)
5852 error ("could not find class$ field in java interface type %qT",
5854 return error_mark_node;
5856 iface_ref = build_address (iface_ref);
5857 iface_ref = convert (build_pointer_type (iface), iface_ref);
5859 /* Determine the itable index of FN. */
5861 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5863 if (!DECL_VIRTUAL_P (method))
5869 idx = build_int_cst (NULL_TREE, i);
5871 lookup_fn = build1 (ADDR_EXPR,
5872 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5873 java_iface_lookup_fn);
5874 return build_call_nary (ptr_type_node, lookup_fn,
5875 3, klass_ref, iface_ref, idx);
5878 /* Returns the value to use for the in-charge parameter when making a
5879 call to a function with the indicated NAME.
5881 FIXME:Can't we find a neater way to do this mapping? */
5884 in_charge_arg_for_name (tree name)
5886 if (name == base_ctor_identifier
5887 || name == base_dtor_identifier)
5888 return integer_zero_node;
5889 else if (name == complete_ctor_identifier)
5890 return integer_one_node;
5891 else if (name == complete_dtor_identifier)
5892 return integer_two_node;
5893 else if (name == deleting_dtor_identifier)
5894 return integer_three_node;
5896 /* This function should only be called with one of the names listed
5902 /* Build a call to a constructor, destructor, or an assignment
5903 operator for INSTANCE, an expression with class type. NAME
5904 indicates the special member function to call; *ARGS are the
5905 arguments. ARGS may be NULL. This may change ARGS. BINFO
5906 indicates the base of INSTANCE that is to be passed as the `this'
5907 parameter to the member function called.
5909 FLAGS are the LOOKUP_* flags to use when processing the call.
5911 If NAME indicates a complete object constructor, INSTANCE may be
5912 NULL_TREE. In this case, the caller will call build_cplus_new to
5913 store the newly constructed object into a VAR_DECL. */
5916 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
5917 tree binfo, int flags, tsubst_flags_t complain)
5920 /* The type of the subobject to be constructed or destroyed. */
5922 VEC(tree,gc) *allocated = NULL;
5925 gcc_assert (name == complete_ctor_identifier
5926 || name == base_ctor_identifier
5927 || name == complete_dtor_identifier
5928 || name == base_dtor_identifier
5929 || name == deleting_dtor_identifier
5930 || name == ansi_assopname (NOP_EXPR));
5933 /* Resolve the name. */
5934 if (!complete_type_or_else (binfo, NULL_TREE))
5935 return error_mark_node;
5937 binfo = TYPE_BINFO (binfo);
5940 gcc_assert (binfo != NULL_TREE);
5942 class_type = BINFO_TYPE (binfo);
5944 /* Handle the special case where INSTANCE is NULL_TREE. */
5945 if (name == complete_ctor_identifier && !instance)
5947 instance = build_int_cst (build_pointer_type (class_type), 0);
5948 instance = build1 (INDIRECT_REF, class_type, instance);
5952 if (name == complete_dtor_identifier
5953 || name == base_dtor_identifier
5954 || name == deleting_dtor_identifier)
5955 gcc_assert (args == NULL || VEC_empty (tree, *args));
5957 /* Convert to the base class, if necessary. */
5958 if (!same_type_ignoring_top_level_qualifiers_p
5959 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5961 if (name != ansi_assopname (NOP_EXPR))
5962 /* For constructors and destructors, either the base is
5963 non-virtual, or it is virtual but we are doing the
5964 conversion from a constructor or destructor for the
5965 complete object. In either case, we can convert
5967 instance = convert_to_base_statically (instance, binfo);
5969 /* However, for assignment operators, we must convert
5970 dynamically if the base is virtual. */
5971 instance = build_base_path (PLUS_EXPR, instance,
5972 binfo, /*nonnull=*/1);
5976 gcc_assert (instance != NULL_TREE);
5978 fns = lookup_fnfields (binfo, name, 1);
5980 /* When making a call to a constructor or destructor for a subobject
5981 that uses virtual base classes, pass down a pointer to a VTT for
5983 if ((name == base_ctor_identifier
5984 || name == base_dtor_identifier)
5985 && CLASSTYPE_VBASECLASSES (class_type))
5990 /* If the current function is a complete object constructor
5991 or destructor, then we fetch the VTT directly.
5992 Otherwise, we look it up using the VTT we were given. */
5993 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5994 vtt = decay_conversion (vtt);
5995 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5996 build2 (EQ_EXPR, boolean_type_node,
5997 current_in_charge_parm, integer_zero_node),
6000 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6001 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6002 BINFO_SUBVTT_INDEX (binfo));
6006 allocated = make_tree_vector ();
6010 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6013 ret = build_new_method_call (instance, fns, args,
6014 TYPE_BINFO (BINFO_TYPE (binfo)),
6018 if (allocated != NULL)
6019 release_tree_vector (allocated);
6024 /* Return the NAME, as a C string. The NAME indicates a function that
6025 is a member of TYPE. *FREE_P is set to true if the caller must
6026 free the memory returned.
6028 Rather than go through all of this, we should simply set the names
6029 of constructors and destructors appropriately, and dispense with
6030 ctor_identifier, dtor_identifier, etc. */
6033 name_as_c_string (tree name, tree type, bool *free_p)
6037 /* Assume that we will not allocate memory. */
6039 /* Constructors and destructors are special. */
6040 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6043 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6044 /* For a destructor, add the '~'. */
6045 if (name == complete_dtor_identifier
6046 || name == base_dtor_identifier
6047 || name == deleting_dtor_identifier)
6049 pretty_name = concat ("~", pretty_name, NULL);
6050 /* Remember that we need to free the memory allocated. */
6054 else if (IDENTIFIER_TYPENAME_P (name))
6056 pretty_name = concat ("operator ",
6057 type_as_string_translate (TREE_TYPE (name),
6058 TFF_PLAIN_IDENTIFIER),
6060 /* Remember that we need to free the memory allocated. */
6064 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6069 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6070 be set, upon return, to the function called. ARGS may be NULL.
6071 This may change ARGS. */
6074 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6075 tree conversion_path, int flags,
6076 tree *fn_p, tsubst_flags_t complain)
6078 struct z_candidate *candidates = 0, *cand;
6079 tree explicit_targs = NULL_TREE;
6080 tree basetype = NULL_TREE;
6083 tree first_mem_arg = NULL_TREE;
6086 bool skip_first_for_error;
6087 VEC(tree,gc) *user_args;
6091 int template_only = 0;
6095 VEC(tree,gc) *orig_args = NULL;
6098 gcc_assert (instance != NULL_TREE);
6100 /* We don't know what function we're going to call, yet. */
6104 if (error_operand_p (instance)
6105 || error_operand_p (fns))
6106 return error_mark_node;
6108 if (!BASELINK_P (fns))
6110 if (complain & tf_error)
6111 error ("call to non-function %qD", fns);
6112 return error_mark_node;
6115 orig_instance = instance;
6118 /* Dismantle the baselink to collect all the information we need. */
6119 if (!conversion_path)
6120 conversion_path = BASELINK_BINFO (fns);
6121 access_binfo = BASELINK_ACCESS_BINFO (fns);
6122 optype = BASELINK_OPTYPE (fns);
6123 fns = BASELINK_FUNCTIONS (fns);
6124 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6126 explicit_targs = TREE_OPERAND (fns, 1);
6127 fns = TREE_OPERAND (fns, 0);
6130 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6131 || TREE_CODE (fns) == TEMPLATE_DECL
6132 || TREE_CODE (fns) == OVERLOAD);
6133 fn = get_first_fn (fns);
6134 name = DECL_NAME (fn);
6136 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6137 gcc_assert (CLASS_TYPE_P (basetype));
6139 if (processing_template_decl)
6141 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6142 instance = build_non_dependent_expr (instance);
6144 make_args_non_dependent (*args);
6147 /* Figure out whether to skip the first argument for the error
6148 message we will display to users if an error occurs. We don't
6149 want to display any compiler-generated arguments. The "this"
6150 pointer hasn't been added yet. However, we must remove the VTT
6151 pointer if this is a call to a base-class constructor or
6153 skip_first_for_error = false;
6154 user_args = args == NULL ? NULL : *args;
6155 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6157 /* Callers should explicitly indicate whether they want to construct
6158 the complete object or just the part without virtual bases. */
6159 gcc_assert (name != ctor_identifier);
6160 /* Similarly for destructors. */
6161 gcc_assert (name != dtor_identifier);
6162 /* Remove the VTT pointer, if present. */
6163 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6164 && CLASSTYPE_VBASECLASSES (basetype))
6165 skip_first_for_error = true;
6168 /* Process the argument list. */
6169 if (args != NULL && *args != NULL)
6171 *args = resolve_args (*args);
6173 return error_mark_node;
6176 instance_ptr = build_this (instance);
6178 /* It's OK to call destructors and constructors on cv-qualified objects.
6179 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6181 if (DECL_DESTRUCTOR_P (fn)
6182 || DECL_CONSTRUCTOR_P (fn))
6184 tree type = build_pointer_type (basetype);
6185 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6186 instance_ptr = build_nop (type, instance_ptr);
6188 if (DECL_DESTRUCTOR_P (fn))
6189 name = complete_dtor_identifier;
6191 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6192 initializer, not T({ }). If the type doesn't have a list ctor,
6193 break apart the list into separate ctor args. */
6194 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6195 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6196 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6197 && !TYPE_HAS_LIST_CTOR (basetype))
6199 gcc_assert (VEC_length (tree, *args) == 1);
6200 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6203 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6204 first_mem_arg = instance_ptr;
6206 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6207 p = conversion_obstack_alloc (0);
6209 for (fn = fns; fn; fn = OVL_NEXT (fn))
6211 tree t = OVL_CURRENT (fn);
6212 tree this_first_arg;
6214 /* We can end up here for copy-init of same or base class. */
6215 if ((flags & LOOKUP_ONLYCONVERTING)
6216 && DECL_NONCONVERTING_P (t))
6219 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6220 this_first_arg = first_mem_arg;
6222 this_first_arg = NULL_TREE;
6224 if (TREE_CODE (t) == TEMPLATE_DECL)
6225 /* A member template. */
6226 add_template_candidate (&candidates, t,
6230 args == NULL ? NULL : *args,
6236 else if (! template_only)
6237 add_function_candidate (&candidates, t,
6240 args == NULL ? NULL : *args,
6246 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6249 if (complain & tf_error)
6251 if (!COMPLETE_TYPE_P (basetype))
6252 cxx_incomplete_type_error (instance_ptr, basetype);
6259 pretty_name = name_as_c_string (name, basetype, &free_p);
6260 arglist = build_tree_list_vec (user_args);
6261 if (skip_first_for_error)
6262 arglist = TREE_CHAIN (arglist);
6263 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6264 basetype, pretty_name, arglist,
6265 TREE_TYPE (TREE_TYPE (instance_ptr)));
6269 print_z_candidates (candidates);
6271 call = error_mark_node;
6275 cand = tourney (candidates);
6282 if (complain & tf_error)
6284 pretty_name = name_as_c_string (name, basetype, &free_p);
6285 arglist = build_tree_list_vec (user_args);
6286 if (skip_first_for_error)
6287 arglist = TREE_CHAIN (arglist);
6288 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6290 print_z_candidates (candidates);
6294 call = error_mark_node;
6300 if (!(flags & LOOKUP_NONVIRTUAL)
6301 && DECL_PURE_VIRTUAL_P (fn)
6302 && instance == current_class_ref
6303 && (DECL_CONSTRUCTOR_P (current_function_decl)
6304 || DECL_DESTRUCTOR_P (current_function_decl))
6305 && (complain & tf_warning))
6306 /* This is not an error, it is runtime undefined
6308 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6309 "abstract virtual %q#D called from constructor"
6310 : "abstract virtual %q#D called from destructor"),
6313 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6314 && is_dummy_object (instance_ptr))
6316 if (complain & tf_error)
6317 error ("cannot call member function %qD without object",
6319 call = error_mark_node;
6323 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6324 && resolves_to_fixed_type_p (instance, 0))
6325 flags |= LOOKUP_NONVIRTUAL;
6326 /* Now we know what function is being called. */
6329 /* Build the actual CALL_EXPR. */
6330 call = build_over_call (cand, flags, complain);
6331 /* In an expression of the form `a->f()' where `f' turns
6332 out to be a static member function, `a' is
6333 none-the-less evaluated. */
6334 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6335 && !is_dummy_object (instance_ptr)
6336 && TREE_SIDE_EFFECTS (instance_ptr))
6337 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6338 instance_ptr, call);
6339 else if (call != error_mark_node
6340 && DECL_DESTRUCTOR_P (cand->fn)
6341 && !VOID_TYPE_P (TREE_TYPE (call)))
6342 /* An explicit call of the form "x->~X()" has type
6343 "void". However, on platforms where destructors
6344 return "this" (i.e., those where
6345 targetm.cxx.cdtor_returns_this is true), such calls
6346 will appear to have a return value of pointer type
6347 to the low-level call machinery. We do not want to
6348 change the low-level machinery, since we want to be
6349 able to optimize "delete f()" on such platforms as
6350 "operator delete(~X(f()))" (rather than generating
6351 "t = f(), ~X(t), operator delete (t)"). */
6352 call = build_nop (void_type_node, call);
6357 if (processing_template_decl && call != error_mark_node)
6359 bool cast_to_void = false;
6361 if (TREE_CODE (call) == COMPOUND_EXPR)
6362 call = TREE_OPERAND (call, 1);
6363 else if (TREE_CODE (call) == NOP_EXPR)
6365 cast_to_void = true;
6366 call = TREE_OPERAND (call, 0);
6368 if (TREE_CODE (call) == INDIRECT_REF)
6369 call = TREE_OPERAND (call, 0);
6370 call = (build_min_non_dep_call_vec
6372 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6373 orig_instance, orig_fns, NULL_TREE),
6375 call = convert_from_reference (call);
6377 call = build_nop (void_type_node, call);
6380 /* Free all the conversions we allocated. */
6381 obstack_free (&conversion_obstack, p);
6383 if (orig_args != NULL)
6384 release_tree_vector (orig_args);
6389 /* Returns true iff standard conversion sequence ICS1 is a proper
6390 subsequence of ICS2. */
6393 is_subseq (conversion *ics1, conversion *ics2)
6395 /* We can assume that a conversion of the same code
6396 between the same types indicates a subsequence since we only get
6397 here if the types we are converting from are the same. */
6399 while (ics1->kind == ck_rvalue
6400 || ics1->kind == ck_lvalue)
6401 ics1 = ics1->u.next;
6405 while (ics2->kind == ck_rvalue
6406 || ics2->kind == ck_lvalue)
6407 ics2 = ics2->u.next;
6409 if (ics2->kind == ck_user
6410 || ics2->kind == ck_ambig
6411 || ics2->kind == ck_identity)
6412 /* At this point, ICS1 cannot be a proper subsequence of
6413 ICS2. We can get a USER_CONV when we are comparing the
6414 second standard conversion sequence of two user conversion
6418 ics2 = ics2->u.next;
6420 if (ics2->kind == ics1->kind
6421 && same_type_p (ics2->type, ics1->type)
6422 && same_type_p (ics2->u.next->type,
6423 ics1->u.next->type))
6428 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6429 be any _TYPE nodes. */
6432 is_properly_derived_from (tree derived, tree base)
6434 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6437 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6438 considers every class derived from itself. */
6439 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6440 && DERIVED_FROM_P (base, derived));
6443 /* We build the ICS for an implicit object parameter as a pointer
6444 conversion sequence. However, such a sequence should be compared
6445 as if it were a reference conversion sequence. If ICS is the
6446 implicit conversion sequence for an implicit object parameter,
6447 modify it accordingly. */
6450 maybe_handle_implicit_object (conversion **ics)
6454 /* [over.match.funcs]
6456 For non-static member functions, the type of the
6457 implicit object parameter is "reference to cv X"
6458 where X is the class of which the function is a
6459 member and cv is the cv-qualification on the member
6460 function declaration. */
6461 conversion *t = *ics;
6462 tree reference_type;
6464 /* The `this' parameter is a pointer to a class type. Make the
6465 implicit conversion talk about a reference to that same class
6467 reference_type = TREE_TYPE (t->type);
6468 reference_type = build_reference_type (reference_type);
6470 if (t->kind == ck_qual)
6472 if (t->kind == ck_ptr)
6474 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6475 t = direct_reference_binding (reference_type, t);
6477 t->rvaluedness_matches_p = 0;
6482 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6483 and return the initial reference binding conversion. Otherwise,
6484 leave *ICS unchanged and return NULL. */
6487 maybe_handle_ref_bind (conversion **ics)
6489 if ((*ics)->kind == ck_ref_bind)
6491 conversion *old_ics = *ics;
6492 *ics = old_ics->u.next;
6493 (*ics)->user_conv_p = old_ics->user_conv_p;
6500 /* Compare two implicit conversion sequences according to the rules set out in
6501 [over.ics.rank]. Return values:
6503 1: ics1 is better than ics2
6504 -1: ics2 is better than ics1
6505 0: ics1 and ics2 are indistinguishable */
6508 compare_ics (conversion *ics1, conversion *ics2)
6514 tree deref_from_type1 = NULL_TREE;
6515 tree deref_from_type2 = NULL_TREE;
6516 tree deref_to_type1 = NULL_TREE;
6517 tree deref_to_type2 = NULL_TREE;
6518 conversion_rank rank1, rank2;
6520 /* REF_BINDING is nonzero if the result of the conversion sequence
6521 is a reference type. In that case REF_CONV is the reference
6522 binding conversion. */
6523 conversion *ref_conv1;
6524 conversion *ref_conv2;
6526 /* Handle implicit object parameters. */
6527 maybe_handle_implicit_object (&ics1);
6528 maybe_handle_implicit_object (&ics2);
6530 /* Handle reference parameters. */
6531 ref_conv1 = maybe_handle_ref_bind (&ics1);
6532 ref_conv2 = maybe_handle_ref_bind (&ics2);
6534 /* List-initialization sequence L1 is a better conversion sequence than
6535 list-initialization sequence L2 if L1 converts to
6536 std::initializer_list<X> for some X and L2 does not. */
6537 if (ics1->kind == ck_list && ics2->kind != ck_list)
6539 if (ics2->kind == ck_list && ics1->kind != ck_list)
6544 When comparing the basic forms of implicit conversion sequences (as
6545 defined in _over.best.ics_)
6547 --a standard conversion sequence (_over.ics.scs_) is a better
6548 conversion sequence than a user-defined conversion sequence
6549 or an ellipsis conversion sequence, and
6551 --a user-defined conversion sequence (_over.ics.user_) is a
6552 better conversion sequence than an ellipsis conversion sequence
6553 (_over.ics.ellipsis_). */
6554 rank1 = CONVERSION_RANK (ics1);
6555 rank2 = CONVERSION_RANK (ics2);
6559 else if (rank1 < rank2)
6562 if (rank1 == cr_bad)
6564 /* XXX Isn't this an extension? */
6565 /* Both ICS are bad. We try to make a decision based on what
6566 would have happened if they'd been good. */
6567 if (ics1->user_conv_p > ics2->user_conv_p
6568 || ics1->rank > ics2->rank)
6570 else if (ics1->user_conv_p < ics2->user_conv_p
6571 || ics1->rank < ics2->rank)
6574 /* We couldn't make up our minds; try to figure it out below. */
6577 if (ics1->ellipsis_p)
6578 /* Both conversions are ellipsis conversions. */
6581 /* User-defined conversion sequence U1 is a better conversion sequence
6582 than another user-defined conversion sequence U2 if they contain the
6583 same user-defined conversion operator or constructor and if the sec-
6584 ond standard conversion sequence of U1 is better than the second
6585 standard conversion sequence of U2. */
6587 if (ics1->user_conv_p)
6592 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
6593 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6595 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
6596 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6599 if (t1->cand->fn != t2->cand->fn)
6602 /* We can just fall through here, after setting up
6603 FROM_TYPE1 and FROM_TYPE2. */
6604 from_type1 = t1->type;
6605 from_type2 = t2->type;
6612 /* We're dealing with two standard conversion sequences.
6616 Standard conversion sequence S1 is a better conversion
6617 sequence than standard conversion sequence S2 if
6619 --S1 is a proper subsequence of S2 (comparing the conversion
6620 sequences in the canonical form defined by _over.ics.scs_,
6621 excluding any Lvalue Transformation; the identity
6622 conversion sequence is considered to be a subsequence of
6623 any non-identity conversion sequence */
6626 while (t1->kind != ck_identity)
6628 from_type1 = t1->type;
6631 while (t2->kind != ck_identity)
6633 from_type2 = t2->type;
6636 /* One sequence can only be a subsequence of the other if they start with
6637 the same type. They can start with different types when comparing the
6638 second standard conversion sequence in two user-defined conversion
6640 if (same_type_p (from_type1, from_type2))
6642 if (is_subseq (ics1, ics2))
6644 if (is_subseq (ics2, ics1))
6652 --the rank of S1 is better than the rank of S2 (by the rules
6655 Standard conversion sequences are ordered by their ranks: an Exact
6656 Match is a better conversion than a Promotion, which is a better
6657 conversion than a Conversion.
6659 Two conversion sequences with the same rank are indistinguishable
6660 unless one of the following rules applies:
6662 --A conversion that is not a conversion of a pointer, or pointer
6663 to member, to bool is better than another conversion that is such
6666 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6667 so that we do not have to check it explicitly. */
6668 if (ics1->rank < ics2->rank)
6670 else if (ics2->rank < ics1->rank)
6673 to_type1 = ics1->type;
6674 to_type2 = ics2->type;
6676 /* A conversion from scalar arithmetic type to complex is worse than a
6677 conversion between scalar arithmetic types. */
6678 if (same_type_p (from_type1, from_type2)
6679 && ARITHMETIC_TYPE_P (from_type1)
6680 && ARITHMETIC_TYPE_P (to_type1)
6681 && ARITHMETIC_TYPE_P (to_type2)
6682 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6683 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6685 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6691 if (TYPE_PTR_P (from_type1)
6692 && TYPE_PTR_P (from_type2)
6693 && TYPE_PTR_P (to_type1)
6694 && TYPE_PTR_P (to_type2))
6696 deref_from_type1 = TREE_TYPE (from_type1);
6697 deref_from_type2 = TREE_TYPE (from_type2);
6698 deref_to_type1 = TREE_TYPE (to_type1);
6699 deref_to_type2 = TREE_TYPE (to_type2);
6701 /* The rules for pointers to members A::* are just like the rules
6702 for pointers A*, except opposite: if B is derived from A then
6703 A::* converts to B::*, not vice versa. For that reason, we
6704 switch the from_ and to_ variables here. */
6705 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6706 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6707 || (TYPE_PTRMEMFUNC_P (from_type1)
6708 && TYPE_PTRMEMFUNC_P (from_type2)
6709 && TYPE_PTRMEMFUNC_P (to_type1)
6710 && TYPE_PTRMEMFUNC_P (to_type2)))
6712 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6713 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6714 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6715 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6718 if (deref_from_type1 != NULL_TREE
6719 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6720 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6722 /* This was one of the pointer or pointer-like conversions.
6726 --If class B is derived directly or indirectly from class A,
6727 conversion of B* to A* is better than conversion of B* to
6728 void*, and conversion of A* to void* is better than
6729 conversion of B* to void*. */
6730 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6731 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6733 if (is_properly_derived_from (deref_from_type1,
6736 else if (is_properly_derived_from (deref_from_type2,
6740 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6741 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6743 if (same_type_p (deref_from_type1, deref_from_type2))
6745 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6747 if (is_properly_derived_from (deref_from_type1,
6751 /* We know that DEREF_TO_TYPE1 is `void' here. */
6752 else if (is_properly_derived_from (deref_from_type1,
6757 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6758 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6762 --If class B is derived directly or indirectly from class A
6763 and class C is derived directly or indirectly from B,
6765 --conversion of C* to B* is better than conversion of C* to
6768 --conversion of B* to A* is better than conversion of C* to
6770 if (same_type_p (deref_from_type1, deref_from_type2))
6772 if (is_properly_derived_from (deref_to_type1,
6775 else if (is_properly_derived_from (deref_to_type2,
6779 else if (same_type_p (deref_to_type1, deref_to_type2))
6781 if (is_properly_derived_from (deref_from_type2,
6784 else if (is_properly_derived_from (deref_from_type1,
6790 else if (CLASS_TYPE_P (non_reference (from_type1))
6791 && same_type_p (from_type1, from_type2))
6793 tree from = non_reference (from_type1);
6797 --binding of an expression of type C to a reference of type
6798 B& is better than binding an expression of type C to a
6799 reference of type A&
6801 --conversion of C to B is better than conversion of C to A, */
6802 if (is_properly_derived_from (from, to_type1)
6803 && is_properly_derived_from (from, to_type2))
6805 if (is_properly_derived_from (to_type1, to_type2))
6807 else if (is_properly_derived_from (to_type2, to_type1))
6811 else if (CLASS_TYPE_P (non_reference (to_type1))
6812 && same_type_p (to_type1, to_type2))
6814 tree to = non_reference (to_type1);
6818 --binding of an expression of type B to a reference of type
6819 A& is better than binding an expression of type C to a
6820 reference of type A&,
6822 --conversion of B to A is better than conversion of C to A */
6823 if (is_properly_derived_from (from_type1, to)
6824 && is_properly_derived_from (from_type2, to))
6826 if (is_properly_derived_from (from_type2, from_type1))
6828 else if (is_properly_derived_from (from_type1, from_type2))
6835 --S1 and S2 differ only in their qualification conversion and yield
6836 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6837 qualification signature of type T1 is a proper subset of the cv-
6838 qualification signature of type T2 */
6839 if (ics1->kind == ck_qual
6840 && ics2->kind == ck_qual
6841 && same_type_p (from_type1, from_type2))
6843 int result = comp_cv_qual_signature (to_type1, to_type2);
6850 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6851 to an implicit object parameter, and either S1 binds an lvalue reference
6852 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6853 reference to an rvalue and S2 binds an lvalue reference
6854 (C++0x draft standard, 13.3.3.2)
6856 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6857 types to which the references refer are the same type except for
6858 top-level cv-qualifiers, and the type to which the reference
6859 initialized by S2 refers is more cv-qualified than the type to
6860 which the reference initialized by S1 refers */
6862 if (ref_conv1 && ref_conv2)
6864 if (!ref_conv1->this_p && !ref_conv2->this_p
6865 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6866 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6868 if (ref_conv1->rvaluedness_matches_p)
6870 if (ref_conv2->rvaluedness_matches_p)
6874 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6875 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6876 TREE_TYPE (ref_conv1->type));
6879 /* Neither conversion sequence is better than the other. */
6883 /* The source type for this standard conversion sequence. */
6886 source_type (conversion *t)
6888 for (;; t = t->u.next)
6890 if (t->kind == ck_user
6891 || t->kind == ck_ambig
6892 || t->kind == ck_identity)
6898 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6899 a pointer to LOSER and re-running joust to produce the warning if WINNER
6900 is actually used. */
6903 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6905 candidate_warning *cw = (candidate_warning *)
6906 conversion_obstack_alloc (sizeof (candidate_warning));
6908 cw->next = winner->warnings;
6909 winner->warnings = cw;
6912 /* Compare two candidates for overloading as described in
6913 [over.match.best]. Return values:
6915 1: cand1 is better than cand2
6916 -1: cand2 is better than cand1
6917 0: cand1 and cand2 are indistinguishable */
6920 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6923 int off1 = 0, off2 = 0;
6927 /* Candidates that involve bad conversions are always worse than those
6929 if (cand1->viable > cand2->viable)
6931 if (cand1->viable < cand2->viable)
6934 /* If we have two pseudo-candidates for conversions to the same type,
6935 or two candidates for the same function, arbitrarily pick one. */
6936 if (cand1->fn == cand2->fn
6937 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6940 /* a viable function F1
6941 is defined to be a better function than another viable function F2 if
6942 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6943 ICSi(F2), and then */
6945 /* for some argument j, ICSj(F1) is a better conversion sequence than
6948 /* For comparing static and non-static member functions, we ignore
6949 the implicit object parameter of the non-static function. The
6950 standard says to pretend that the static function has an object
6951 parm, but that won't work with operator overloading. */
6952 len = cand1->num_convs;
6953 if (len != cand2->num_convs)
6955 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6956 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6958 gcc_assert (static_1 != static_2);
6969 for (i = 0; i < len; ++i)
6971 conversion *t1 = cand1->convs[i + off1];
6972 conversion *t2 = cand2->convs[i + off2];
6973 int comp = compare_ics (t1, t2);
6978 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6979 == cr_std + cr_promotion)
6980 && t1->kind == ck_std
6981 && t2->kind == ck_std
6982 && TREE_CODE (t1->type) == INTEGER_TYPE
6983 && TREE_CODE (t2->type) == INTEGER_TYPE
6984 && (TYPE_PRECISION (t1->type)
6985 == TYPE_PRECISION (t2->type))
6986 && (TYPE_UNSIGNED (t1->u.next->type)
6987 || (TREE_CODE (t1->u.next->type)
6990 tree type = t1->u.next->type;
6992 struct z_candidate *w, *l;
6994 type1 = t1->type, type2 = t2->type,
6995 w = cand1, l = cand2;
6997 type1 = t2->type, type2 = t1->type,
6998 w = cand2, l = cand1;
7002 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7003 type, type1, type2);
7004 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7010 if (winner && comp != winner)
7019 /* warn about confusing overload resolution for user-defined conversions,
7020 either between a constructor and a conversion op, or between two
7022 if (winner && warn_conversion && cand1->second_conv
7023 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7024 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7026 struct z_candidate *w, *l;
7027 bool give_warning = false;
7030 w = cand1, l = cand2;
7032 w = cand2, l = cand1;
7034 /* We don't want to complain about `X::operator T1 ()'
7035 beating `X::operator T2 () const', when T2 is a no less
7036 cv-qualified version of T1. */
7037 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7038 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7040 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7041 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7043 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7048 if (!comp_ptr_ttypes (t, f))
7049 give_warning = true;
7052 give_warning = true;
7058 tree source = source_type (w->convs[0]);
7059 if (! DECL_CONSTRUCTOR_P (w->fn))
7060 source = TREE_TYPE (source);
7061 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7062 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7063 source, w->second_conv->type))
7065 inform (input_location, " because conversion sequence for the argument is better");
7076 F1 is a non-template function and F2 is a template function
7079 if (!cand1->template_decl && cand2->template_decl)
7081 else if (cand1->template_decl && !cand2->template_decl)
7085 F1 and F2 are template functions and the function template for F1 is
7086 more specialized than the template for F2 according to the partial
7089 if (cand1->template_decl && cand2->template_decl)
7091 winner = more_specialized_fn
7092 (TI_TEMPLATE (cand1->template_decl),
7093 TI_TEMPLATE (cand2->template_decl),
7094 /* [temp.func.order]: The presence of unused ellipsis and default
7095 arguments has no effect on the partial ordering of function
7096 templates. add_function_candidate() will not have
7097 counted the "this" argument for constructors. */
7098 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7104 the context is an initialization by user-defined conversion (see
7105 _dcl.init_ and _over.match.user_) and the standard conversion
7106 sequence from the return type of F1 to the destination type (i.e.,
7107 the type of the entity being initialized) is a better conversion
7108 sequence than the standard conversion sequence from the return type
7109 of F2 to the destination type. */
7111 if (cand1->second_conv)
7113 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7118 /* Check whether we can discard a builtin candidate, either because we
7119 have two identical ones or matching builtin and non-builtin candidates.
7121 (Pedantically in the latter case the builtin which matched the user
7122 function should not be added to the overload set, but we spot it here.
7125 ... the builtin candidates include ...
7126 - do not have the same parameter type list as any non-template
7127 non-member candidate. */
7129 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7130 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7132 for (i = 0; i < len; ++i)
7133 if (!same_type_p (cand1->convs[i]->type,
7134 cand2->convs[i]->type))
7136 if (i == cand1->num_convs)
7138 if (cand1->fn == cand2->fn)
7139 /* Two built-in candidates; arbitrarily pick one. */
7141 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7142 /* cand1 is built-in; prefer cand2. */
7145 /* cand2 is built-in; prefer cand1. */
7150 /* If the two function declarations represent the same function (this can
7151 happen with declarations in multiple scopes and arg-dependent lookup),
7152 arbitrarily choose one. But first make sure the default args we're
7154 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7155 && equal_functions (cand1->fn, cand2->fn))
7157 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7158 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7160 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7162 for (i = 0; i < len; ++i)
7164 /* Don't crash if the fn is variadic. */
7167 parms1 = TREE_CHAIN (parms1);
7168 parms2 = TREE_CHAIN (parms2);
7172 parms1 = TREE_CHAIN (parms1);
7174 parms2 = TREE_CHAIN (parms2);
7178 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7179 TREE_PURPOSE (parms2)))
7183 permerror (input_location, "default argument mismatch in "
7184 "overload resolution");
7185 inform (input_location,
7186 " candidate 1: %q+#F", cand1->fn);
7187 inform (input_location,
7188 " candidate 2: %q+#F", cand2->fn);
7191 add_warning (cand1, cand2);
7194 parms1 = TREE_CHAIN (parms1);
7195 parms2 = TREE_CHAIN (parms2);
7203 /* Extension: If the worst conversion for one candidate is worse than the
7204 worst conversion for the other, take the first. */
7207 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7208 struct z_candidate *w = 0, *l = 0;
7210 for (i = 0; i < len; ++i)
7212 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7213 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7214 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7215 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7218 winner = 1, w = cand1, l = cand2;
7220 winner = -1, w = cand2, l = cand1;
7225 pedwarn (input_location, 0,
7226 "ISO C++ says that these are ambiguous, even "
7227 "though the worst conversion for the first is better than "
7228 "the worst conversion for the second:");
7229 print_z_candidate (_("candidate 1:"), w);
7230 print_z_candidate (_("candidate 2:"), l);
7238 gcc_assert (!winner);
7242 /* Given a list of candidates for overloading, find the best one, if any.
7243 This algorithm has a worst case of O(2n) (winner is last), and a best
7244 case of O(n/2) (totally ambiguous); much better than a sorting
7247 static struct z_candidate *
7248 tourney (struct z_candidate *candidates)
7250 struct z_candidate *champ = candidates, *challenger;
7252 int champ_compared_to_predecessor = 0;
7254 /* Walk through the list once, comparing each current champ to the next
7255 candidate, knocking out a candidate or two with each comparison. */
7257 for (challenger = champ->next; challenger; )
7259 fate = joust (champ, challenger, 0);
7261 challenger = challenger->next;
7266 champ = challenger->next;
7269 champ_compared_to_predecessor = 0;
7274 champ_compared_to_predecessor = 1;
7277 challenger = champ->next;
7281 /* Make sure the champ is better than all the candidates it hasn't yet
7282 been compared to. */
7284 for (challenger = candidates;
7286 && !(champ_compared_to_predecessor && challenger->next == champ);
7287 challenger = challenger->next)
7289 fate = joust (champ, challenger, 0);
7297 /* Returns nonzero if things of type FROM can be converted to TO. */
7300 can_convert (tree to, tree from)
7302 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7305 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7308 can_convert_arg (tree to, tree from, tree arg, int flags)
7314 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7315 p = conversion_obstack_alloc (0);
7317 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7319 ok_p = (t && !t->bad_p);
7321 /* Free all the conversions we allocated. */
7322 obstack_free (&conversion_obstack, p);
7327 /* Like can_convert_arg, but allows dubious conversions as well. */
7330 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7335 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7336 p = conversion_obstack_alloc (0);
7337 /* Try to perform the conversion. */
7338 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7340 /* Free all the conversions we allocated. */
7341 obstack_free (&conversion_obstack, p);
7346 /* Convert EXPR to TYPE. Return the converted expression.
7348 Note that we allow bad conversions here because by the time we get to
7349 this point we are committed to doing the conversion. If we end up
7350 doing a bad conversion, convert_like will complain. */
7353 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7358 if (error_operand_p (expr))
7359 return error_mark_node;
7361 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7362 p = conversion_obstack_alloc (0);
7364 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7370 if (complain & tf_error)
7372 /* If expr has unknown type, then it is an overloaded function.
7373 Call instantiate_type to get good error messages. */
7374 if (TREE_TYPE (expr) == unknown_type_node)
7375 instantiate_type (type, expr, complain);
7376 else if (invalid_nonstatic_memfn_p (expr, complain))
7377 /* We gave an error. */;
7379 error ("could not convert %qE to %qT", expr, type);
7381 expr = error_mark_node;
7383 else if (processing_template_decl)
7385 /* In a template, we are only concerned about determining the
7386 type of non-dependent expressions, so we do not have to
7387 perform the actual conversion. */
7388 if (TREE_TYPE (expr) != type)
7389 expr = build_nop (type, expr);
7392 expr = convert_like (conv, expr, complain);
7394 /* Free all the conversions we allocated. */
7395 obstack_free (&conversion_obstack, p);
7401 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7403 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7406 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7407 permitted. If the conversion is valid, the converted expression is
7408 returned. Otherwise, NULL_TREE is returned, except in the case
7409 that TYPE is a class type; in that case, an error is issued. If
7410 C_CAST_P is true, then this direction initialization is taking
7411 place as part of a static_cast being attempted as part of a C-style
7415 perform_direct_initialization_if_possible (tree type,
7418 tsubst_flags_t complain)
7423 if (type == error_mark_node || error_operand_p (expr))
7424 return error_mark_node;
7427 If the destination type is a (possibly cv-qualified) class type:
7429 -- If the initialization is direct-initialization ...,
7430 constructors are considered. ... If no constructor applies, or
7431 the overload resolution is ambiguous, the initialization is
7433 if (CLASS_TYPE_P (type))
7435 VEC(tree,gc) *args = make_tree_vector_single (expr);
7436 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7437 &args, type, LOOKUP_NORMAL, complain);
7438 release_tree_vector (args);
7439 return build_cplus_new (type, expr);
7442 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7443 p = conversion_obstack_alloc (0);
7445 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7448 if (!conv || conv->bad_p)
7451 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7452 /*issue_conversion_warnings=*/false,
7454 tf_warning_or_error);
7456 /* Free all the conversions we allocated. */
7457 obstack_free (&conversion_obstack, p);
7462 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7463 is being bound to a temporary. Create and return a new VAR_DECL
7464 with the indicated TYPE; this variable will store the value to
7465 which the reference is bound. */
7468 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7472 /* Create the variable. */
7473 var = create_temporary_var (type);
7475 /* Register the variable. */
7476 if (TREE_STATIC (decl))
7478 /* Namespace-scope or local static; give it a mangled name. */
7481 TREE_STATIC (var) = 1;
7482 name = mangle_ref_init_variable (decl);
7483 DECL_NAME (var) = name;
7484 SET_DECL_ASSEMBLER_NAME (var, name);
7485 var = pushdecl_top_level (var);
7488 /* Create a new cleanup level if necessary. */
7489 maybe_push_cleanup_level (type);
7494 /* EXPR is the initializer for a variable DECL of reference or
7495 std::initializer_list type. Create, push and return a new VAR_DECL
7496 for the initializer so that it will live as long as DECL. Any
7497 cleanup for the new variable is returned through CLEANUP, and the
7498 code to initialize the new variable is returned through INITP. */
7501 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7507 /* Create the temporary variable. */
7508 type = TREE_TYPE (expr);
7509 var = make_temporary_var_for_ref_to_temp (decl, type);
7510 layout_decl (var, 0);
7511 /* If the rvalue is the result of a function call it will be
7512 a TARGET_EXPR. If it is some other construct (such as a
7513 member access expression where the underlying object is
7514 itself the result of a function call), turn it into a
7515 TARGET_EXPR here. It is important that EXPR be a
7516 TARGET_EXPR below since otherwise the INIT_EXPR will
7517 attempt to make a bitwise copy of EXPR to initialize
7519 if (TREE_CODE (expr) != TARGET_EXPR)
7520 expr = get_target_expr (expr);
7521 /* Create the INIT_EXPR that will initialize the temporary
7523 init = build2 (INIT_EXPR, type, var, expr);
7524 if (at_function_scope_p ())
7526 add_decl_expr (var);
7528 if (TREE_STATIC (var))
7529 init = add_stmt_to_compound (init, register_dtor_fn (var));
7531 *cleanup = cxx_maybe_build_cleanup (var);
7533 /* We must be careful to destroy the temporary only
7534 after its initialization has taken place. If the
7535 initialization throws an exception, then the
7536 destructor should not be run. We cannot simply
7537 transform INIT into something like:
7539 (INIT, ({ CLEANUP_STMT; }))
7541 because emit_local_var always treats the
7542 initializer as a full-expression. Thus, the
7543 destructor would run too early; it would run at the
7544 end of initializing the reference variable, rather
7545 than at the end of the block enclosing the
7548 The solution is to pass back a cleanup expression
7549 which the caller is responsible for attaching to
7550 the statement tree. */
7554 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7555 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7556 static_aggregates = tree_cons (NULL_TREE, var,
7564 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7565 initializing a variable of that TYPE. If DECL is non-NULL, it is
7566 the VAR_DECL being initialized with the EXPR. (In that case, the
7567 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7568 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7569 return, if *CLEANUP is no longer NULL, it will be an expression
7570 that should be pushed as a cleanup after the returned expression
7571 is used to initialize DECL.
7573 Return the converted expression. */
7576 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7581 if (type == error_mark_node || error_operand_p (expr))
7582 return error_mark_node;
7584 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7585 p = conversion_obstack_alloc (0);
7587 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7589 if (!conv || conv->bad_p)
7591 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7592 && !TYPE_REF_IS_RVALUE (type)
7593 && !real_lvalue_p (expr))
7594 error ("invalid initialization of non-const reference of "
7595 "type %qT from a temporary of type %qT",
7596 type, TREE_TYPE (expr));
7598 error ("invalid initialization of reference of type "
7599 "%qT from expression of type %qT", type,
7601 return error_mark_node;
7604 /* If DECL is non-NULL, then this special rule applies:
7608 The temporary to which the reference is bound or the temporary
7609 that is the complete object to which the reference is bound
7610 persists for the lifetime of the reference.
7612 The temporaries created during the evaluation of the expression
7613 initializing the reference, except the temporary to which the
7614 reference is bound, are destroyed at the end of the
7615 full-expression in which they are created.
7617 In that case, we store the converted expression into a new
7618 VAR_DECL in a new scope.
7620 However, we want to be careful not to create temporaries when
7621 they are not required. For example, given:
7624 struct D : public B {};
7628 there is no need to copy the return value from "f"; we can just
7629 extend its lifetime. Similarly, given:
7632 struct T { operator S(); };
7636 we can extend the lifetime of the return value of the conversion
7638 gcc_assert (conv->kind == ck_ref_bind);
7642 tree base_conv_type;
7644 /* Skip over the REF_BIND. */
7645 conv = conv->u.next;
7646 /* If the next conversion is a BASE_CONV, skip that too -- but
7647 remember that the conversion was required. */
7648 if (conv->kind == ck_base)
7650 base_conv_type = conv->type;
7651 conv = conv->u.next;
7654 base_conv_type = NULL_TREE;
7655 /* Perform the remainder of the conversion. */
7656 expr = convert_like_real (conv, expr,
7657 /*fn=*/NULL_TREE, /*argnum=*/0,
7659 /*issue_conversion_warnings=*/true,
7661 tf_warning_or_error);
7662 if (error_operand_p (expr))
7663 expr = error_mark_node;
7666 if (!lvalue_or_rvalue_with_address_p (expr))
7669 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7670 /* Use its address to initialize the reference variable. */
7671 expr = build_address (var);
7673 expr = convert_to_base (expr,
7674 build_pointer_type (base_conv_type),
7675 /*check_access=*/true,
7677 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7680 /* Take the address of EXPR. */
7681 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7682 /* If a BASE_CONV was required, perform it now. */
7684 expr = (perform_implicit_conversion
7685 (build_pointer_type (base_conv_type), expr,
7686 tf_warning_or_error));
7687 expr = build_nop (type, expr);
7691 /* Perform the conversion. */
7692 expr = convert_like (conv, expr, tf_warning_or_error);
7694 /* Free all the conversions we allocated. */
7695 obstack_free (&conversion_obstack, p);
7700 /* Returns true iff TYPE is some variant of std::initializer_list. */
7703 is_std_init_list (tree type)
7705 return (CLASS_TYPE_P (type)
7706 && CP_TYPE_CONTEXT (type) == std_node
7707 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7710 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7711 will accept an argument list of a single std::initializer_list<T>. */
7714 is_list_ctor (tree decl)
7716 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7719 if (!args || args == void_list_node)
7722 arg = non_reference (TREE_VALUE (args));
7723 if (!is_std_init_list (arg))
7726 args = TREE_CHAIN (args);
7728 if (args && args != void_list_node && !TREE_PURPOSE (args))
7729 /* There are more non-defaulted parms. */
7735 #include "gt-cp-call.h"