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
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 tree build_object_call (tree, tree, tsubst_flags_t);
149 static tree resolve_args (tree);
150 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
151 static void print_z_candidate (const char *, struct z_candidate *);
152 static void print_z_candidates (struct z_candidate *);
153 static tree build_this (tree);
154 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
155 static bool any_strictly_viable (struct z_candidate *);
156 static struct z_candidate *add_template_candidate
157 (struct z_candidate **, tree, tree, tree, tree, tree,
158 tree, tree, int, unification_kind_t);
159 static struct z_candidate *add_template_candidate_real
160 (struct z_candidate **, tree, tree, tree, tree, tree,
161 tree, tree, int, tree, unification_kind_t);
162 static struct z_candidate *add_template_conv_candidate
163 (struct z_candidate **, tree, tree, tree, tree, tree, 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, tree, tree);
176 static struct z_candidate *add_function_candidate
177 (struct z_candidate **, tree, tree, tree, tree, tree, int);
178 static conversion *implicit_conversion (tree, tree, tree, bool, int);
179 static conversion *standard_conversion (tree, tree, tree, bool, int);
180 static conversion *reference_binding (tree, tree, tree, bool, int);
181 static conversion *build_conv (conversion_kind, tree, conversion *);
182 static conversion *build_list_conv (tree, tree, int);
183 static bool is_subseq (conversion *, conversion *);
184 static conversion *maybe_handle_ref_bind (conversion **);
185 static void maybe_handle_implicit_object (conversion **);
186 static struct z_candidate *add_candidate
187 (struct z_candidate **, tree, tree, size_t,
188 conversion **, tree, tree, int);
189 static tree source_type (conversion *);
190 static void add_warning (struct z_candidate *, struct z_candidate *);
191 static bool reference_related_p (tree, tree);
192 static bool reference_compatible_p (tree, tree);
193 static conversion *convert_class_to_reference (tree, tree, tree);
194 static conversion *direct_reference_binding (tree, conversion *);
195 static bool promoted_arithmetic_type_p (tree);
196 static conversion *conditional_conversion (tree, tree);
197 static char *name_as_c_string (tree, tree, bool *);
198 static tree call_builtin_trap (void);
199 static tree prep_operand (tree);
200 static void add_candidates (tree, tree, 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));
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);
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 (result_type, function, n, argarray);
365 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
366 TREE_NOTHROW (function) = nothrow;
371 /* Build something of the form ptr->method (args)
372 or object.method (args). This can also build
373 calls to constructors, and find friends.
375 Member functions always take their class variable
378 INSTANCE is a class instance.
380 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
382 PARMS help to figure out what that NAME really refers to.
384 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
385 down to the real instance type to use for access checking. We need this
386 information to get protected accesses correct.
388 FLAGS is the logical disjunction of zero or more LOOKUP_
389 flags. See cp-tree.h for more info.
391 If this is all OK, calls build_function_call with the resolved
394 This function must also handle being called to perform
395 initialization, promotion/coercion of arguments, and
396 instantiation of default parameters.
398 Note that NAME may refer to an instance variable name. If
399 `operator()()' is defined for the type of that field, then we return
402 /* New overloading code. */
404 typedef struct z_candidate z_candidate;
406 typedef struct candidate_warning candidate_warning;
407 struct candidate_warning {
409 candidate_warning *next;
413 /* The FUNCTION_DECL that will be called if this candidate is
414 selected by overload resolution. */
416 /* The arguments to use when calling this function. */
418 /* The implicit conversion sequences for each of the arguments to
421 /* The number of implicit conversion sequences. */
423 /* If FN is a user-defined conversion, the standard conversion
424 sequence from the type returned by FN to the desired destination
426 conversion *second_conv;
428 /* If FN is a member function, the binfo indicating the path used to
429 qualify the name of FN at the call site. This path is used to
430 determine whether or not FN is accessible if it is selected by
431 overload resolution. The DECL_CONTEXT of FN will always be a
432 (possibly improper) base of this binfo. */
434 /* If FN is a non-static member function, the binfo indicating the
435 subobject to which the `this' pointer should be converted if FN
436 is selected by overload resolution. The type pointed to the by
437 the `this' pointer must correspond to the most derived class
438 indicated by the CONVERSION_PATH. */
439 tree conversion_path;
441 candidate_warning *warnings;
445 /* Returns true iff T is a null pointer constant in the sense of
449 null_ptr_cst_p (tree t)
453 A null pointer constant is an integral constant expression
454 (_expr.const_) rvalue of integer type that evaluates to zero. */
455 t = integral_constant_value (t);
458 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
461 if (!TREE_OVERFLOW (t))
467 /* Returns nonzero if PARMLIST consists of only default parms and/or
471 sufficient_parms_p (const_tree parmlist)
473 for (; parmlist && parmlist != void_list_node;
474 parmlist = TREE_CHAIN (parmlist))
475 if (!TREE_PURPOSE (parmlist))
480 /* Allocate N bytes of memory from the conversion obstack. The memory
481 is zeroed before being returned. */
484 conversion_obstack_alloc (size_t n)
487 if (!conversion_obstack_initialized)
489 gcc_obstack_init (&conversion_obstack);
490 conversion_obstack_initialized = true;
492 p = obstack_alloc (&conversion_obstack, n);
497 /* Dynamically allocate a conversion. */
500 alloc_conversion (conversion_kind kind)
503 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
508 #ifdef ENABLE_CHECKING
510 /* Make sure that all memory on the conversion obstack has been
514 validate_conversion_obstack (void)
516 if (conversion_obstack_initialized)
517 gcc_assert ((obstack_next_free (&conversion_obstack)
518 == obstack_base (&conversion_obstack)));
521 #endif /* ENABLE_CHECKING */
523 /* Dynamically allocate an array of N conversions. */
526 alloc_conversions (size_t n)
528 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
532 build_conv (conversion_kind code, tree type, conversion *from)
535 conversion_rank rank = CONVERSION_RANK (from);
537 /* Note that the caller is responsible for filling in t->cand for
538 user-defined conversions. */
539 t = alloc_conversion (code);
562 t->user_conv_p = (code == ck_user || from->user_conv_p);
563 t->bad_p = from->bad_p;
568 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
569 specialization of std::initializer_list<T>, if such a conversion is
573 build_list_conv (tree type, tree ctor, int flags)
575 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
576 unsigned len = CONSTRUCTOR_NELTS (ctor);
577 conversion **subconvs = alloc_conversions (len);
582 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
585 = implicit_conversion (elttype, TREE_TYPE (val), val,
593 t = alloc_conversion (ck_list);
595 t->u.list = subconvs;
598 for (i = 0; i < len; ++i)
600 conversion *sub = subconvs[i];
601 if (sub->rank > t->rank)
603 if (sub->user_conv_p)
604 t->user_conv_p = true;
612 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
613 aggregate class, if such a conversion is possible. */
616 build_aggr_conv (tree type, tree ctor, int flags)
618 unsigned HOST_WIDE_INT i = 0;
620 tree field = TYPE_FIELDS (type);
622 for (; field; field = TREE_CHAIN (field), ++i)
624 if (TREE_CODE (field) != FIELD_DECL)
626 if (i < CONSTRUCTOR_NELTS (ctor))
628 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
629 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
633 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
637 c = alloc_conversion (ck_aggr);
640 c->user_conv_p = true;
645 /* Build a representation of the identity conversion from EXPR to
646 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
649 build_identity_conv (tree type, tree expr)
653 c = alloc_conversion (ck_identity);
660 /* Converting from EXPR to TYPE was ambiguous in the sense that there
661 were multiple user-defined conversions to accomplish the job.
662 Build a conversion that indicates that ambiguity. */
665 build_ambiguous_conv (tree type, tree expr)
669 c = alloc_conversion (ck_ambig);
677 strip_top_quals (tree t)
679 if (TREE_CODE (t) == ARRAY_TYPE)
681 return cp_build_qualified_type (t, 0);
684 /* Returns the standard conversion path (see [conv]) from type FROM to type
685 TO, if any. For proper handling of null pointer constants, you must
686 also pass the expression EXPR to convert from. If C_CAST_P is true,
687 this conversion is coming from a C-style cast. */
690 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
693 enum tree_code fcode, tcode;
695 bool fromref = false;
697 to = non_reference (to);
698 if (TREE_CODE (from) == REFERENCE_TYPE)
701 from = TREE_TYPE (from);
703 to = strip_top_quals (to);
704 from = strip_top_quals (from);
706 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
707 && expr && type_unknown_p (expr))
709 expr = instantiate_type (to, expr, tf_conv);
710 if (expr == error_mark_node)
712 from = TREE_TYPE (expr);
715 fcode = TREE_CODE (from);
716 tcode = TREE_CODE (to);
718 conv = build_identity_conv (from, expr);
719 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
721 from = type_decays_to (from);
722 fcode = TREE_CODE (from);
723 conv = build_conv (ck_lvalue, from, conv);
725 else if (fromref || (expr && lvalue_p (expr)))
730 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
733 from = strip_top_quals (bitfield_type);
734 fcode = TREE_CODE (from);
737 conv = build_conv (ck_rvalue, from, conv);
740 /* Allow conversion between `__complex__' data types. */
741 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
743 /* The standard conversion sequence to convert FROM to TO is
744 the standard conversion sequence to perform componentwise
746 conversion *part_conv = standard_conversion
747 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
751 conv = build_conv (part_conv->kind, to, conv);
752 conv->rank = part_conv->rank;
760 if (same_type_p (from, to))
763 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
764 && expr && null_ptr_cst_p (expr))
765 conv = build_conv (ck_std, to, conv);
766 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
767 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
769 /* For backwards brain damage compatibility, allow interconversion of
770 pointers and integers with a pedwarn. */
771 conv = build_conv (ck_std, to, conv);
774 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
776 /* For backwards brain damage compatibility, allow interconversion of
777 enums and integers with a pedwarn. */
778 conv = build_conv (ck_std, to, conv);
781 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
782 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
787 if (tcode == POINTER_TYPE
788 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
791 else if (VOID_TYPE_P (TREE_TYPE (to))
792 && !TYPE_PTRMEM_P (from)
793 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
795 from = build_pointer_type
796 (cp_build_qualified_type (void_type_node,
797 cp_type_quals (TREE_TYPE (from))));
798 conv = build_conv (ck_ptr, from, conv);
800 else if (TYPE_PTRMEM_P (from))
802 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
803 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
805 if (DERIVED_FROM_P (fbase, tbase)
806 && (same_type_ignoring_top_level_qualifiers_p
807 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
808 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
810 from = build_ptrmem_type (tbase,
811 TYPE_PTRMEM_POINTED_TO_TYPE (from));
812 conv = build_conv (ck_pmem, from, conv);
814 else if (!same_type_p (fbase, tbase))
817 else if (CLASS_TYPE_P (TREE_TYPE (from))
818 && CLASS_TYPE_P (TREE_TYPE (to))
821 An rvalue of type "pointer to cv D," where D is a
822 class type, can be converted to an rvalue of type
823 "pointer to cv B," where B is a base class (clause
824 _class.derived_) of D. If B is an inaccessible
825 (clause _class.access_) or ambiguous
826 (_class.member.lookup_) base class of D, a program
827 that necessitates this conversion is ill-formed.
828 Therefore, we use DERIVED_FROM_P, and do not check
829 access or uniqueness. */
830 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
833 cp_build_qualified_type (TREE_TYPE (to),
834 cp_type_quals (TREE_TYPE (from)));
835 from = build_pointer_type (from);
836 conv = build_conv (ck_ptr, from, conv);
840 if (tcode == POINTER_TYPE)
842 to_pointee = TREE_TYPE (to);
843 from_pointee = TREE_TYPE (from);
847 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
848 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
851 if (same_type_p (from, to))
853 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
854 /* In a C-style cast, we ignore CV-qualification because we
855 are allowed to perform a static_cast followed by a
857 conv = build_conv (ck_qual, to, conv);
858 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
859 conv = build_conv (ck_qual, to, conv);
860 else if (expr && string_conv_p (to, expr, 0))
861 /* converting from string constant to char *. */
862 conv = build_conv (ck_qual, to, conv);
863 else if (ptr_reasonably_similar (to_pointee, from_pointee))
865 conv = build_conv (ck_ptr, to, conv);
873 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
875 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
876 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
877 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
878 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
880 if (!DERIVED_FROM_P (fbase, tbase)
881 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
882 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
883 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
884 || cp_type_quals (fbase) != cp_type_quals (tbase))
887 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
888 from = build_method_type_directly (from,
890 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
891 from = build_ptrmemfunc_type (build_pointer_type (from));
892 conv = build_conv (ck_pmem, from, conv);
895 else if (tcode == BOOLEAN_TYPE)
899 An rvalue of arithmetic, unscoped enumeration, pointer, or
900 pointer to member type can be converted to an rvalue of type
902 if (ARITHMETIC_TYPE_P (from)
903 || UNSCOPED_ENUM_P (from)
904 || fcode == POINTER_TYPE
905 || TYPE_PTR_TO_MEMBER_P (from))
907 conv = build_conv (ck_std, to, conv);
908 if (fcode == POINTER_TYPE
909 || TYPE_PTRMEM_P (from)
910 || (TYPE_PTRMEMFUNC_P (from)
911 && conv->rank < cr_pbool))
912 conv->rank = cr_pbool;
918 /* We don't check for ENUMERAL_TYPE here because there are no standard
919 conversions to enum type. */
920 /* As an extension, allow conversion to complex type. */
921 else if (ARITHMETIC_TYPE_P (to))
923 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
924 || SCOPED_ENUM_P (from))
926 conv = build_conv (ck_std, to, conv);
928 /* Give this a better rank if it's a promotion. */
929 if (same_type_p (to, type_promotes_to (from))
930 && conv->u.next->rank <= cr_promotion)
931 conv->rank = cr_promotion;
933 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
934 && vector_types_convertible_p (from, to, false))
935 return build_conv (ck_std, to, conv);
936 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
937 && is_properly_derived_from (from, to))
939 if (conv->kind == ck_rvalue)
941 conv = build_conv (ck_base, to, conv);
942 /* The derived-to-base conversion indicates the initialization
943 of a parameter with base type from an object of a derived
944 type. A temporary object is created to hold the result of
945 the conversion unless we're binding directly to a reference. */
946 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
951 if (flags & LOOKUP_NO_NARROWING)
952 conv->check_narrowing = true;
957 /* Returns nonzero if T1 is reference-related to T2. */
960 reference_related_p (tree t1, tree t2)
962 t1 = TYPE_MAIN_VARIANT (t1);
963 t2 = TYPE_MAIN_VARIANT (t2);
967 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
968 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
970 return (same_type_p (t1, t2)
971 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
972 && DERIVED_FROM_P (t1, t2)));
975 /* Returns nonzero if T1 is reference-compatible with T2. */
978 reference_compatible_p (tree t1, tree t2)
982 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
983 reference-related to T2 and cv1 is the same cv-qualification as,
984 or greater cv-qualification than, cv2. */
985 return (reference_related_p (t1, t2)
986 && at_least_as_qualified_p (t1, t2));
989 /* Determine whether or not the EXPR (of class type S) can be
990 converted to T as in [over.match.ref]. */
993 convert_class_to_reference (tree reference_type, tree s, tree expr)
999 struct z_candidate *candidates;
1000 struct z_candidate *cand;
1003 conversions = lookup_conversions (s);
1009 Assuming that "cv1 T" is the underlying type of the reference
1010 being initialized, and "cv S" is the type of the initializer
1011 expression, with S a class type, the candidate functions are
1012 selected as follows:
1014 --The conversion functions of S and its base classes are
1015 considered. Those that are not hidden within S and yield type
1016 "reference to cv2 T2", where "cv1 T" is reference-compatible
1017 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1019 The argument list has one argument, which is the initializer
1024 /* Conceptually, we should take the address of EXPR and put it in
1025 the argument list. Unfortunately, however, that can result in
1026 error messages, which we should not issue now because we are just
1027 trying to find a conversion operator. Therefore, we use NULL,
1028 cast to the appropriate type. */
1029 arglist = build_int_cst (build_pointer_type (s), 0);
1030 arglist = build_tree_list (NULL_TREE, arglist);
1032 t = TREE_TYPE (reference_type);
1036 tree fns = TREE_VALUE (conversions);
1038 for (; fns; fns = OVL_NEXT (fns))
1040 tree f = OVL_CURRENT (fns);
1041 tree t2 = TREE_TYPE (TREE_TYPE (f));
1045 /* If this is a template function, try to get an exact
1047 if (TREE_CODE (f) == TEMPLATE_DECL)
1049 cand = add_template_candidate (&candidates,
1055 TREE_PURPOSE (conversions),
1061 /* Now, see if the conversion function really returns
1062 an lvalue of the appropriate type. From the
1063 point of view of unification, simply returning an
1064 rvalue of the right type is good enough. */
1066 t2 = TREE_TYPE (TREE_TYPE (f));
1067 if (TREE_CODE (t2) != REFERENCE_TYPE
1068 || !reference_compatible_p (t, TREE_TYPE (t2)))
1070 candidates = candidates->next;
1075 else if (TREE_CODE (t2) == REFERENCE_TYPE
1076 && reference_compatible_p (t, TREE_TYPE (t2)))
1077 cand = add_function_candidate (&candidates, f, s, arglist,
1079 TREE_PURPOSE (conversions),
1084 conversion *identity_conv;
1085 /* Build a standard conversion sequence indicating the
1086 binding from the reference type returned by the
1087 function to the desired REFERENCE_TYPE. */
1089 = build_identity_conv (TREE_TYPE (TREE_TYPE
1090 (TREE_TYPE (cand->fn))),
1093 = (direct_reference_binding
1094 (reference_type, identity_conv));
1095 cand->second_conv->rvaluedness_matches_p
1096 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1097 == TYPE_REF_IS_RVALUE (reference_type);
1098 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1101 conversions = TREE_CHAIN (conversions);
1104 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1105 /* If none of the conversion functions worked out, let our caller
1110 cand = tourney (candidates);
1114 /* Now that we know that this is the function we're going to use fix
1115 the dummy first argument. */
1116 cand->args = tree_cons (NULL_TREE,
1118 TREE_CHAIN (cand->args));
1120 /* Build a user-defined conversion sequence representing the
1122 conv = build_conv (ck_user,
1123 TREE_TYPE (TREE_TYPE (cand->fn)),
1124 build_identity_conv (TREE_TYPE (expr), expr));
1127 /* Merge it with the standard conversion sequence from the
1128 conversion function's return type to the desired type. */
1129 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1131 if (cand->viable == -1)
1134 return cand->second_conv;
1137 /* A reference of the indicated TYPE is being bound directly to the
1138 expression represented by the implicit conversion sequence CONV.
1139 Return a conversion sequence for this binding. */
1142 direct_reference_binding (tree type, conversion *conv)
1146 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1147 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1149 t = TREE_TYPE (type);
1153 When a parameter of reference type binds directly
1154 (_dcl.init.ref_) to an argument expression, the implicit
1155 conversion sequence is the identity conversion, unless the
1156 argument expression has a type that is a derived class of the
1157 parameter type, in which case the implicit conversion sequence is
1158 a derived-to-base Conversion.
1160 If the parameter binds directly to the result of applying a
1161 conversion function to the argument expression, the implicit
1162 conversion sequence is a user-defined conversion sequence
1163 (_over.ics.user_), with the second standard conversion sequence
1164 either an identity conversion or, if the conversion function
1165 returns an entity of a type that is a derived class of the
1166 parameter type, a derived-to-base conversion. */
1167 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1169 /* Represent the derived-to-base conversion. */
1170 conv = build_conv (ck_base, t, conv);
1171 /* We will actually be binding to the base-class subobject in
1172 the derived class, so we mark this conversion appropriately.
1173 That way, convert_like knows not to generate a temporary. */
1174 conv->need_temporary_p = false;
1176 return build_conv (ck_ref_bind, type, conv);
1179 /* Returns the conversion path from type FROM to reference type TO for
1180 purposes of reference binding. For lvalue binding, either pass a
1181 reference type to FROM or an lvalue expression to EXPR. If the
1182 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1183 the conversion returned. If C_CAST_P is true, this
1184 conversion is coming from a C-style cast. */
1187 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1189 conversion *conv = NULL;
1190 tree to = TREE_TYPE (rto);
1195 cp_lvalue_kind lvalue_p = clk_none;
1197 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1199 expr = instantiate_type (to, expr, tf_none);
1200 if (expr == error_mark_node)
1202 from = TREE_TYPE (expr);
1205 if (TREE_CODE (from) == REFERENCE_TYPE)
1207 /* Anything with reference type is an lvalue. */
1208 lvalue_p = clk_ordinary;
1209 from = TREE_TYPE (from);
1212 lvalue_p = real_lvalue_p (expr);
1215 if ((lvalue_p & clk_bitfield) != 0)
1216 tfrom = unlowered_expr_type (expr);
1218 /* Figure out whether or not the types are reference-related and
1219 reference compatible. We have do do this after stripping
1220 references from FROM. */
1221 related_p = reference_related_p (to, tfrom);
1222 /* If this is a C cast, first convert to an appropriately qualified
1223 type, so that we can later do a const_cast to the desired type. */
1224 if (related_p && c_cast_p
1225 && !at_least_as_qualified_p (to, tfrom))
1226 to = build_qualified_type (to, cp_type_quals (tfrom));
1227 compatible_p = reference_compatible_p (to, tfrom);
1229 /* Directly bind reference when target expression's type is compatible with
1230 the reference and expression is an lvalue. In DR391, the wording in
1231 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1232 const and rvalue references to rvalues of compatible class type. */
1235 || (!(flags & LOOKUP_NO_TEMP_BIND)
1236 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1237 && CLASS_TYPE_P (from))))
1241 If the initializer expression
1243 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1244 is reference-compatible with "cv2 T2,"
1246 the reference is bound directly to the initializer expression
1250 If the initializer expression is an rvalue, with T2 a class type,
1251 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1252 is bound to the object represented by the rvalue or to a sub-object
1253 within that object. */
1255 conv = build_identity_conv (tfrom, expr);
1256 conv = direct_reference_binding (rto, conv);
1258 if (flags & LOOKUP_PREFER_RVALUE)
1259 /* The top-level caller requested that we pretend that the lvalue
1260 be treated as an rvalue. */
1261 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1263 conv->rvaluedness_matches_p
1264 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1266 if ((lvalue_p & clk_bitfield) != 0
1267 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1268 /* For the purposes of overload resolution, we ignore the fact
1269 this expression is a bitfield or packed field. (In particular,
1270 [over.ics.ref] says specifically that a function with a
1271 non-const reference parameter is viable even if the
1272 argument is a bitfield.)
1274 However, when we actually call the function we must create
1275 a temporary to which to bind the reference. If the
1276 reference is volatile, or isn't const, then we cannot make
1277 a temporary, so we just issue an error when the conversion
1279 conv->need_temporary_p = true;
1283 /* [class.conv.fct] A conversion function is never used to convert a
1284 (possibly cv-qualified) object to the (possibly cv-qualified) same
1285 object type (or a reference to it), to a (possibly cv-qualified) base
1286 class of that type (or a reference to it).... */
1287 else if (CLASS_TYPE_P (from) && !related_p
1288 && !(flags & LOOKUP_NO_CONVERSION))
1292 If the initializer expression
1294 -- has a class type (i.e., T2 is a class type) can be
1295 implicitly converted to an lvalue of type "cv3 T3," where
1296 "cv1 T1" is reference-compatible with "cv3 T3". (this
1297 conversion is selected by enumerating the applicable
1298 conversion functions (_over.match.ref_) and choosing the
1299 best one through overload resolution. (_over.match_).
1301 the reference is bound to the lvalue result of the conversion
1302 in the second case. */
1303 conv = convert_class_to_reference (rto, from, expr);
1308 /* From this point on, we conceptually need temporaries, even if we
1309 elide them. Only the cases above are "direct bindings". */
1310 if (flags & LOOKUP_NO_TEMP_BIND)
1315 When a parameter of reference type is not bound directly to an
1316 argument expression, the conversion sequence is the one required
1317 to convert the argument expression to the underlying type of the
1318 reference according to _over.best.ics_. Conceptually, this
1319 conversion sequence corresponds to copy-initializing a temporary
1320 of the underlying type with the argument expression. Any
1321 difference in top-level cv-qualification is subsumed by the
1322 initialization itself and does not constitute a conversion. */
1326 Otherwise, the reference shall be to a non-volatile const type.
1328 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1329 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1334 Otherwise, a temporary of type "cv1 T1" is created and
1335 initialized from the initializer expression using the rules for a
1336 non-reference copy initialization. If T1 is reference-related to
1337 T2, cv1 must be the same cv-qualification as, or greater
1338 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1339 if (related_p && !at_least_as_qualified_p (to, from))
1342 /* We're generating a temporary now, but don't bind any more in the
1343 conversion (specifically, don't slice the temporary returned by a
1344 conversion operator). */
1345 flags |= LOOKUP_NO_TEMP_BIND;
1347 conv = implicit_conversion (to, from, expr, c_cast_p,
1352 conv = build_conv (ck_ref_bind, rto, conv);
1353 /* This reference binding, unlike those above, requires the
1354 creation of a temporary. */
1355 conv->need_temporary_p = true;
1356 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1361 /* Returns the implicit conversion sequence (see [over.ics]) from type
1362 FROM to type TO. The optional expression EXPR may affect the
1363 conversion. FLAGS are the usual overloading flags. Only
1364 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1365 conversion is coming from a C-style cast. */
1368 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1373 if (from == error_mark_node || to == error_mark_node
1374 || expr == error_mark_node)
1377 if (TREE_CODE (to) == REFERENCE_TYPE)
1378 conv = reference_binding (to, from, expr, c_cast_p, flags);
1380 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1385 if (is_std_init_list (to) && expr
1386 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1387 return build_list_conv (to, expr, flags);
1389 if (expr != NULL_TREE
1390 && (MAYBE_CLASS_TYPE_P (from)
1391 || MAYBE_CLASS_TYPE_P (to))
1392 && (flags & LOOKUP_NO_CONVERSION) == 0)
1394 struct z_candidate *cand;
1395 int convflags = ((flags & LOOKUP_NO_TEMP_BIND)
1396 |LOOKUP_ONLYCONVERTING);
1398 if (CLASS_TYPE_P (to)
1399 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1400 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1401 return build_aggr_conv (to, expr, flags);
1403 cand = build_user_type_conversion_1 (to, expr, convflags);
1405 conv = cand->second_conv;
1407 /* We used to try to bind a reference to a temporary here, but that
1408 is now handled after the recursive call to this function at the end
1409 of reference_binding. */
1416 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1419 static struct z_candidate *
1420 add_candidate (struct z_candidate **candidates,
1422 size_t num_convs, conversion **convs,
1423 tree access_path, tree conversion_path,
1426 struct z_candidate *cand = (struct z_candidate *)
1427 conversion_obstack_alloc (sizeof (struct z_candidate));
1431 cand->convs = convs;
1432 cand->num_convs = num_convs;
1433 cand->access_path = access_path;
1434 cand->conversion_path = conversion_path;
1435 cand->viable = viable;
1436 cand->next = *candidates;
1442 /* Create an overload candidate for the function or method FN called with
1443 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1444 to implicit_conversion.
1446 CTYPE, if non-NULL, is the type we want to pretend this function
1447 comes from for purposes of overload resolution. */
1449 static struct z_candidate *
1450 add_function_candidate (struct z_candidate **candidates,
1451 tree fn, tree ctype, tree arglist,
1452 tree access_path, tree conversion_path,
1455 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1458 tree parmnode, argnode;
1462 /* At this point we should not see any functions which haven't been
1463 explicitly declared, except for friend functions which will have
1464 been found using argument dependent lookup. */
1465 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1467 /* The `this', `in_chrg' and VTT arguments to constructors are not
1468 considered in overload resolution. */
1469 if (DECL_CONSTRUCTOR_P (fn))
1471 parmlist = skip_artificial_parms_for (fn, parmlist);
1472 orig_arglist = arglist;
1473 arglist = skip_artificial_parms_for (fn, arglist);
1476 orig_arglist = arglist;
1478 len = list_length (arglist);
1479 convs = alloc_conversions (len);
1481 /* 13.3.2 - Viable functions [over.match.viable]
1482 First, to be a viable function, a candidate function shall have enough
1483 parameters to agree in number with the arguments in the list.
1485 We need to check this first; otherwise, checking the ICSes might cause
1486 us to produce an ill-formed template instantiation. */
1488 parmnode = parmlist;
1489 for (i = 0; i < len; ++i)
1491 if (parmnode == NULL_TREE || parmnode == void_list_node)
1493 parmnode = TREE_CHAIN (parmnode);
1496 if (i < len && parmnode)
1499 /* Make sure there are default args for the rest of the parms. */
1500 else if (!sufficient_parms_p (parmnode))
1506 /* Second, for F to be a viable function, there shall exist for each
1507 argument an implicit conversion sequence that converts that argument
1508 to the corresponding parameter of F. */
1510 parmnode = parmlist;
1513 for (i = 0; i < len; ++i)
1515 tree arg = TREE_VALUE (argnode);
1516 tree argtype = lvalue_type (arg);
1520 if (parmnode == void_list_node)
1523 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1524 && ! DECL_CONSTRUCTOR_P (fn));
1528 tree parmtype = TREE_VALUE (parmnode);
1531 /* The type of the implicit object parameter ('this') for
1532 overload resolution is not always the same as for the
1533 function itself; conversion functions are considered to
1534 be members of the class being converted, and functions
1535 introduced by a using-declaration are considered to be
1536 members of the class that uses them.
1538 Since build_over_call ignores the ICS for the `this'
1539 parameter, we can just change the parm type. */
1540 if (ctype && is_this)
1543 = build_qualified_type (ctype,
1544 TYPE_QUALS (TREE_TYPE (parmtype)));
1545 parmtype = build_pointer_type (parmtype);
1548 if ((flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1549 && ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1550 lflags |= LOOKUP_NO_CONVERSION;
1552 t = implicit_conversion (parmtype, argtype, arg,
1553 /*c_cast_p=*/false, lflags);
1557 t = build_identity_conv (argtype, arg);
1558 t->ellipsis_p = true;
1575 parmnode = TREE_CHAIN (parmnode);
1576 argnode = TREE_CHAIN (argnode);
1580 return add_candidate (candidates, fn, orig_arglist, len, convs,
1581 access_path, conversion_path, viable);
1584 /* Create an overload candidate for the conversion function FN which will
1585 be invoked for expression OBJ, producing a pointer-to-function which
1586 will in turn be called with the argument list ARGLIST, and add it to
1587 CANDIDATES. FLAGS is passed on to implicit_conversion.
1589 Actually, we don't really care about FN; we care about the type it
1590 converts to. There may be multiple conversion functions that will
1591 convert to that type, and we rely on build_user_type_conversion_1 to
1592 choose the best one; so when we create our candidate, we record the type
1593 instead of the function. */
1595 static struct z_candidate *
1596 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1597 tree arglist, tree access_path, tree conversion_path)
1599 tree totype = TREE_TYPE (TREE_TYPE (fn));
1600 int i, len, viable, flags;
1601 tree parmlist, parmnode, argnode;
1604 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1605 parmlist = TREE_TYPE (parmlist);
1606 parmlist = TYPE_ARG_TYPES (parmlist);
1608 len = list_length (arglist) + 1;
1609 convs = alloc_conversions (len);
1610 parmnode = parmlist;
1613 flags = LOOKUP_NORMAL;
1615 /* Don't bother looking up the same type twice. */
1616 if (*candidates && (*candidates)->fn == totype)
1619 for (i = 0; i < len; ++i)
1621 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1622 tree argtype = lvalue_type (arg);
1626 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1628 else if (parmnode == void_list_node)
1631 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1632 /*c_cast_p=*/false, flags);
1635 t = build_identity_conv (argtype, arg);
1636 t->ellipsis_p = true;
1650 parmnode = TREE_CHAIN (parmnode);
1651 argnode = TREE_CHAIN (argnode);
1657 if (!sufficient_parms_p (parmnode))
1660 return add_candidate (candidates, totype, arglist, len, convs,
1661 access_path, conversion_path, viable);
1665 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1666 tree type1, tree type2, tree *args, tree *argtypes,
1678 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1679 convs = alloc_conversions (num_convs);
1681 for (i = 0; i < 2; ++i)
1686 t = implicit_conversion (types[i], argtypes[i], args[i],
1687 /*c_cast_p=*/false, flags);
1691 /* We need something for printing the candidate. */
1692 t = build_identity_conv (types[i], NULL_TREE);
1699 /* For COND_EXPR we rearranged the arguments; undo that now. */
1702 convs[2] = convs[1];
1703 convs[1] = convs[0];
1704 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1705 /*c_cast_p=*/false, flags);
1712 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1714 /*access_path=*/NULL_TREE,
1715 /*conversion_path=*/NULL_TREE,
1720 is_complete (tree t)
1722 return COMPLETE_TYPE_P (complete_type (t));
1725 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1728 promoted_arithmetic_type_p (tree type)
1732 In this section, the term promoted integral type is used to refer
1733 to those integral types which are preserved by integral promotion
1734 (including e.g. int and long but excluding e.g. char).
1735 Similarly, the term promoted arithmetic type refers to promoted
1736 integral types plus floating types. */
1737 return ((INTEGRAL_TYPE_P (type)
1738 && same_type_p (type_promotes_to (type), type))
1739 || TREE_CODE (type) == REAL_TYPE);
1742 /* Create any builtin operator overload candidates for the operator in
1743 question given the converted operand types TYPE1 and TYPE2. The other
1744 args are passed through from add_builtin_candidates to
1745 build_builtin_candidate.
1747 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1748 If CODE is requires candidates operands of the same type of the kind
1749 of which TYPE1 and TYPE2 are, we add both candidates
1750 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1753 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1754 enum tree_code code2, tree fnname, tree type1,
1755 tree type2, tree *args, tree *argtypes, int flags)
1759 case POSTINCREMENT_EXPR:
1760 case POSTDECREMENT_EXPR:
1761 args[1] = integer_zero_node;
1762 type2 = integer_type_node;
1771 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1772 and VQ is either volatile or empty, there exist candidate operator
1773 functions of the form
1774 VQ T& operator++(VQ T&);
1775 T operator++(VQ T&, int);
1776 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1777 type other than bool, and VQ is either volatile or empty, there exist
1778 candidate operator functions of the form
1779 VQ T& operator--(VQ T&);
1780 T operator--(VQ T&, int);
1781 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1782 complete object type, and VQ is either volatile or empty, there exist
1783 candidate operator functions of the form
1784 T*VQ& operator++(T*VQ&);
1785 T*VQ& operator--(T*VQ&);
1786 T* operator++(T*VQ&, int);
1787 T* operator--(T*VQ&, int); */
1789 case POSTDECREMENT_EXPR:
1790 case PREDECREMENT_EXPR:
1791 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1793 case POSTINCREMENT_EXPR:
1794 case PREINCREMENT_EXPR:
1795 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1797 type1 = build_reference_type (type1);
1802 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1803 exist candidate operator functions of the form
1807 8 For every function type T, there exist candidate operator functions of
1809 T& operator*(T*); */
1812 if (TREE_CODE (type1) == POINTER_TYPE
1813 && (TYPE_PTROB_P (type1)
1814 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1818 /* 9 For every type T, there exist candidate operator functions of the form
1821 10For every promoted arithmetic type T, there exist candidate operator
1822 functions of the form
1826 case UNARY_PLUS_EXPR: /* unary + */
1827 if (TREE_CODE (type1) == POINTER_TYPE)
1830 if (ARITHMETIC_TYPE_P (type1))
1834 /* 11For every promoted integral type T, there exist candidate operator
1835 functions of the form
1839 if (INTEGRAL_TYPE_P (type1))
1843 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1844 is the same type as C2 or is a derived class of C2, T is a complete
1845 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1846 there exist candidate operator functions of the form
1847 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1848 where CV12 is the union of CV1 and CV2. */
1851 if (TREE_CODE (type1) == POINTER_TYPE
1852 && TYPE_PTR_TO_MEMBER_P (type2))
1854 tree c1 = TREE_TYPE (type1);
1855 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1857 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1858 && (TYPE_PTRMEMFUNC_P (type2)
1859 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1864 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1865 didate operator functions of the form
1870 bool operator<(L, R);
1871 bool operator>(L, R);
1872 bool operator<=(L, R);
1873 bool operator>=(L, R);
1874 bool operator==(L, R);
1875 bool operator!=(L, R);
1876 where LR is the result of the usual arithmetic conversions between
1879 14For every pair of types T and I, where T is a cv-qualified or cv-
1880 unqualified complete object type and I is a promoted integral type,
1881 there exist candidate operator functions of the form
1882 T* operator+(T*, I);
1883 T& operator[](T*, I);
1884 T* operator-(T*, I);
1885 T* operator+(I, T*);
1886 T& operator[](I, T*);
1888 15For every T, where T is a pointer to complete object type, there exist
1889 candidate operator functions of the form112)
1890 ptrdiff_t operator-(T, T);
1892 16For every pointer or enumeration type T, there exist candidate operator
1893 functions of the form
1894 bool operator<(T, T);
1895 bool operator>(T, T);
1896 bool operator<=(T, T);
1897 bool operator>=(T, T);
1898 bool operator==(T, T);
1899 bool operator!=(T, T);
1901 17For every pointer to member type T, there exist candidate operator
1902 functions of the form
1903 bool operator==(T, T);
1904 bool operator!=(T, T); */
1907 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1909 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1911 type2 = ptrdiff_type_node;
1915 case TRUNC_DIV_EXPR:
1916 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1922 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1923 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1925 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1930 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1942 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1944 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1946 if (TREE_CODE (type1) == ENUMERAL_TYPE
1947 && TREE_CODE (type2) == ENUMERAL_TYPE)
1949 if (TYPE_PTR_P (type1)
1950 && null_ptr_cst_p (args[1])
1951 && !uses_template_parms (type1))
1956 if (null_ptr_cst_p (args[0])
1957 && TYPE_PTR_P (type2)
1958 && !uses_template_parms (type2))
1966 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1969 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1971 type1 = ptrdiff_type_node;
1974 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1976 type2 = ptrdiff_type_node;
1981 /* 18For every pair of promoted integral types L and R, there exist candi-
1982 date operator functions of the form
1989 where LR is the result of the usual arithmetic conversions between
1992 case TRUNC_MOD_EXPR:
1998 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2002 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2003 type, VQ is either volatile or empty, and R is a promoted arithmetic
2004 type, there exist candidate operator functions of the form
2005 VQ L& operator=(VQ L&, R);
2006 VQ L& operator*=(VQ L&, R);
2007 VQ L& operator/=(VQ L&, R);
2008 VQ L& operator+=(VQ L&, R);
2009 VQ L& operator-=(VQ L&, R);
2011 20For every pair T, VQ), where T is any type and VQ is either volatile
2012 or empty, there exist candidate operator functions of the form
2013 T*VQ& operator=(T*VQ&, T*);
2015 21For every pair T, VQ), where T is a pointer to member type and VQ is
2016 either volatile or empty, there exist candidate operator functions of
2018 VQ T& operator=(VQ T&, T);
2020 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2021 unqualified complete object type, VQ is either volatile or empty, and
2022 I is a promoted integral type, there exist candidate operator func-
2024 T*VQ& operator+=(T*VQ&, I);
2025 T*VQ& operator-=(T*VQ&, I);
2027 23For every triple L, VQ, R), where L is an integral or enumeration
2028 type, VQ is either volatile or empty, and R is a promoted integral
2029 type, there exist candidate operator functions of the form
2031 VQ L& operator%=(VQ L&, R);
2032 VQ L& operator<<=(VQ L&, R);
2033 VQ L& operator>>=(VQ L&, R);
2034 VQ L& operator&=(VQ L&, R);
2035 VQ L& operator^=(VQ L&, R);
2036 VQ L& operator|=(VQ L&, R); */
2043 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
2045 type2 = ptrdiff_type_node;
2049 case TRUNC_DIV_EXPR:
2050 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2054 case TRUNC_MOD_EXPR:
2060 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2065 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2067 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2068 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2069 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2070 || ((TYPE_PTRMEMFUNC_P (type1)
2071 || TREE_CODE (type1) == POINTER_TYPE)
2072 && null_ptr_cst_p (args[1])))
2082 type1 = build_reference_type (type1);
2088 For every pair of promoted arithmetic types L and R, there
2089 exist candidate operator functions of the form
2091 LR operator?(bool, L, R);
2093 where LR is the result of the usual arithmetic conversions
2094 between types L and R.
2096 For every type T, where T is a pointer or pointer-to-member
2097 type, there exist candidate operator functions of the form T
2098 operator?(bool, T, T); */
2100 if (promoted_arithmetic_type_p (type1)
2101 && promoted_arithmetic_type_p (type2))
2105 /* Otherwise, the types should be pointers. */
2106 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2107 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2110 /* We don't check that the two types are the same; the logic
2111 below will actually create two candidates; one in which both
2112 parameter types are TYPE1, and one in which both parameter
2120 /* If we're dealing with two pointer types or two enumeral types,
2121 we need candidates for both of them. */
2122 if (type2 && !same_type_p (type1, type2)
2123 && TREE_CODE (type1) == TREE_CODE (type2)
2124 && (TREE_CODE (type1) == REFERENCE_TYPE
2125 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2126 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2127 || TYPE_PTRMEMFUNC_P (type1)
2128 || MAYBE_CLASS_TYPE_P (type1)
2129 || TREE_CODE (type1) == ENUMERAL_TYPE))
2131 build_builtin_candidate
2132 (candidates, fnname, type1, type1, args, argtypes, flags);
2133 build_builtin_candidate
2134 (candidates, fnname, type2, type2, args, argtypes, flags);
2138 build_builtin_candidate
2139 (candidates, fnname, type1, type2, args, argtypes, flags);
2143 type_decays_to (tree type)
2145 if (TREE_CODE (type) == ARRAY_TYPE)
2146 return build_pointer_type (TREE_TYPE (type));
2147 if (TREE_CODE (type) == FUNCTION_TYPE)
2148 return build_pointer_type (type);
2152 /* There are three conditions of builtin candidates:
2154 1) bool-taking candidates. These are the same regardless of the input.
2155 2) pointer-pair taking candidates. These are generated for each type
2156 one of the input types converts to.
2157 3) arithmetic candidates. According to the standard, we should generate
2158 all of these, but I'm trying not to...
2160 Here we generate a superset of the possible candidates for this particular
2161 case. That is a subset of the full set the standard defines, plus some
2162 other cases which the standard disallows. add_builtin_candidate will
2163 filter out the invalid set. */
2166 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2167 enum tree_code code2, tree fnname, tree *args,
2172 tree type, argtypes[3];
2173 /* TYPES[i] is the set of possible builtin-operator parameter types
2174 we will consider for the Ith argument. These are represented as
2175 a TREE_LIST; the TREE_VALUE of each node is the potential
2179 for (i = 0; i < 3; ++i)
2182 argtypes[i] = unlowered_expr_type (args[i]);
2184 argtypes[i] = NULL_TREE;
2189 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2190 and VQ is either volatile or empty, there exist candidate operator
2191 functions of the form
2192 VQ T& operator++(VQ T&); */
2194 case POSTINCREMENT_EXPR:
2195 case PREINCREMENT_EXPR:
2196 case POSTDECREMENT_EXPR:
2197 case PREDECREMENT_EXPR:
2202 /* 24There also exist candidate operator functions of the form
2203 bool operator!(bool);
2204 bool operator&&(bool, bool);
2205 bool operator||(bool, bool); */
2207 case TRUTH_NOT_EXPR:
2208 build_builtin_candidate
2209 (candidates, fnname, boolean_type_node,
2210 NULL_TREE, args, argtypes, flags);
2213 case TRUTH_ORIF_EXPR:
2214 case TRUTH_ANDIF_EXPR:
2215 build_builtin_candidate
2216 (candidates, fnname, boolean_type_node,
2217 boolean_type_node, args, argtypes, flags);
2239 types[0] = types[1] = NULL_TREE;
2241 for (i = 0; i < 2; ++i)
2245 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2249 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2252 convs = lookup_conversions (argtypes[i]);
2254 if (code == COND_EXPR)
2256 if (real_lvalue_p (args[i]))
2257 types[i] = tree_cons
2258 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2260 types[i] = tree_cons
2261 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2267 for (; convs; convs = TREE_CHAIN (convs))
2269 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2272 && (TREE_CODE (type) != REFERENCE_TYPE
2273 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2276 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2277 types[i] = tree_cons (NULL_TREE, type, types[i]);
2279 type = non_reference (type);
2280 if (i != 0 || ! ref1)
2282 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2283 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2284 types[i] = tree_cons (NULL_TREE, type, types[i]);
2285 if (INTEGRAL_TYPE_P (type))
2286 type = type_promotes_to (type);
2289 if (! value_member (type, types[i]))
2290 types[i] = tree_cons (NULL_TREE, type, types[i]);
2295 if (code == COND_EXPR && real_lvalue_p (args[i]))
2296 types[i] = tree_cons
2297 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2298 type = non_reference (argtypes[i]);
2299 if (i != 0 || ! ref1)
2301 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2302 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2303 types[i] = tree_cons (NULL_TREE, type, types[i]);
2304 if (INTEGRAL_TYPE_P (type))
2305 type = type_promotes_to (type);
2307 types[i] = tree_cons (NULL_TREE, type, types[i]);
2311 /* Run through the possible parameter types of both arguments,
2312 creating candidates with those parameter types. */
2313 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2316 for (type = types[1]; type; type = TREE_CHAIN (type))
2317 add_builtin_candidate
2318 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2319 TREE_VALUE (type), args, argtypes, flags);
2321 add_builtin_candidate
2322 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2323 NULL_TREE, args, argtypes, flags);
2328 /* If TMPL can be successfully instantiated as indicated by
2329 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2331 TMPL is the template. EXPLICIT_TARGS are any explicit template
2332 arguments. ARGLIST is the arguments provided at the call-site.
2333 The RETURN_TYPE is the desired type for conversion operators. If
2334 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2335 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2336 add_conv_candidate. */
2338 static struct z_candidate*
2339 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2340 tree ctype, tree explicit_targs, tree arglist,
2341 tree return_type, tree access_path,
2342 tree conversion_path, int flags, tree obj,
2343 unification_kind_t strict)
2345 int ntparms = DECL_NTPARMS (tmpl);
2346 tree targs = make_tree_vec (ntparms);
2347 tree args_without_in_chrg = arglist;
2348 struct z_candidate *cand;
2352 /* We don't do deduction on the in-charge parameter, the VTT
2353 parameter or 'this'. */
2354 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2355 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2357 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2358 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2359 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2360 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2362 i = fn_type_unification (tmpl, explicit_targs, targs,
2363 args_without_in_chrg,
2364 return_type, strict, flags);
2369 fn = instantiate_template (tmpl, targs, tf_none);
2370 if (fn == error_mark_node)
2375 A member function template is never instantiated to perform the
2376 copy of a class object to an object of its class type.
2378 It's a little unclear what this means; the standard explicitly
2379 does allow a template to be used to copy a class. For example,
2384 template <class T> A(const T&);
2387 void g () { A a (f ()); }
2389 the member template will be used to make the copy. The section
2390 quoted above appears in the paragraph that forbids constructors
2391 whose only parameter is (a possibly cv-qualified variant of) the
2392 class type, and a logical interpretation is that the intent was
2393 to forbid the instantiation of member templates which would then
2395 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2397 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2398 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2403 if (obj != NULL_TREE)
2404 /* Aha, this is a conversion function. */
2405 cand = add_conv_candidate (candidates, fn, obj, access_path,
2406 conversion_path, arglist);
2408 cand = add_function_candidate (candidates, fn, ctype,
2409 arglist, access_path,
2410 conversion_path, flags);
2411 if (DECL_TI_TEMPLATE (fn) != tmpl)
2412 /* This situation can occur if a member template of a template
2413 class is specialized. Then, instantiate_template might return
2414 an instantiation of the specialization, in which case the
2415 DECL_TI_TEMPLATE field will point at the original
2416 specialization. For example:
2418 template <class T> struct S { template <class U> void f(U);
2419 template <> void f(int) {}; };
2423 Here, TMPL will be template <class U> S<double>::f(U).
2424 And, instantiate template will give us the specialization
2425 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2426 for this will point at template <class T> template <> S<T>::f(int),
2427 so that we can find the definition. For the purposes of
2428 overload resolution, however, we want the original TMPL. */
2429 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2431 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2437 static struct z_candidate *
2438 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2439 tree explicit_targs, tree arglist, tree return_type,
2440 tree access_path, tree conversion_path, int flags,
2441 unification_kind_t strict)
2444 add_template_candidate_real (candidates, tmpl, ctype,
2445 explicit_targs, arglist, return_type,
2446 access_path, conversion_path,
2447 flags, NULL_TREE, strict);
2451 static struct z_candidate *
2452 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2453 tree obj, tree arglist, tree return_type,
2454 tree access_path, tree conversion_path)
2457 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2458 arglist, return_type, access_path,
2459 conversion_path, 0, obj, DEDUCE_CONV);
2462 /* The CANDS are the set of candidates that were considered for
2463 overload resolution. Return the set of viable candidates. If none
2464 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2465 is true if a candidate should be considered viable only if it is
2468 static struct z_candidate*
2469 splice_viable (struct z_candidate *cands,
2473 struct z_candidate *viable;
2474 struct z_candidate **last_viable;
2475 struct z_candidate **cand;
2478 last_viable = &viable;
2479 *any_viable_p = false;
2484 struct z_candidate *c = *cand;
2485 if (strict_p ? c->viable == 1 : c->viable)
2490 last_viable = &c->next;
2491 *any_viable_p = true;
2497 return viable ? viable : cands;
2501 any_strictly_viable (struct z_candidate *cands)
2503 for (; cands; cands = cands->next)
2504 if (cands->viable == 1)
2509 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2510 words, it is about to become the "this" pointer for a member
2511 function call. Take the address of the object. */
2514 build_this (tree obj)
2516 /* In a template, we are only concerned about the type of the
2517 expression, so we can take a shortcut. */
2518 if (processing_template_decl)
2519 return build_address (obj);
2521 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2524 /* Returns true iff functions are equivalent. Equivalent functions are
2525 not '==' only if one is a function-local extern function or if
2526 both are extern "C". */
2529 equal_functions (tree fn1, tree fn2)
2531 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2532 || DECL_EXTERN_C_FUNCTION_P (fn1))
2533 return decls_match (fn1, fn2);
2537 /* Print information about one overload candidate CANDIDATE. MSGSTR
2538 is the text to print before the candidate itself.
2540 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2541 to have been run through gettext by the caller. This wart makes
2542 life simpler in print_z_candidates and for the translators. */
2545 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2547 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2549 if (candidate->num_convs == 3)
2550 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2551 candidate->convs[0]->type,
2552 candidate->convs[1]->type,
2553 candidate->convs[2]->type);
2554 else if (candidate->num_convs == 2)
2555 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2556 candidate->convs[0]->type,
2557 candidate->convs[1]->type);
2559 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2560 candidate->convs[0]->type);
2562 else if (TYPE_P (candidate->fn))
2563 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2564 else if (candidate->viable == -1)
2565 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2567 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2571 print_z_candidates (struct z_candidate *candidates)
2574 struct z_candidate *cand1;
2575 struct z_candidate **cand2;
2577 /* There may be duplicates in the set of candidates. We put off
2578 checking this condition as long as possible, since we have no way
2579 to eliminate duplicates from a set of functions in less than n^2
2580 time. Now we are about to emit an error message, so it is more
2581 permissible to go slowly. */
2582 for (cand1 = candidates; cand1; cand1 = cand1->next)
2584 tree fn = cand1->fn;
2585 /* Skip builtin candidates and conversion functions. */
2586 if (TREE_CODE (fn) != FUNCTION_DECL)
2588 cand2 = &cand1->next;
2591 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2592 && equal_functions (fn, (*cand2)->fn))
2593 *cand2 = (*cand2)->next;
2595 cand2 = &(*cand2)->next;
2602 str = _("candidates are:");
2603 print_z_candidate (str, candidates);
2604 if (candidates->next)
2606 /* Indent successive candidates by the width of the translation
2607 of the above string. */
2608 size_t len = gcc_gettext_width (str) + 1;
2609 char *spaces = (char *) alloca (len);
2610 memset (spaces, ' ', len-1);
2611 spaces[len - 1] = '\0';
2613 candidates = candidates->next;
2616 print_z_candidate (spaces, candidates);
2617 candidates = candidates->next;
2623 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2624 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2625 the result of the conversion function to convert it to the final
2626 desired type. Merge the two sequences into a single sequence,
2627 and return the merged sequence. */
2630 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2634 gcc_assert (user_seq->kind == ck_user);
2636 /* Find the end of the second conversion sequence. */
2638 while ((*t)->kind != ck_identity)
2639 t = &((*t)->u.next);
2641 /* Replace the identity conversion with the user conversion
2645 /* The entire sequence is a user-conversion sequence. */
2646 std_seq->user_conv_p = true;
2651 /* Returns the best overload candidate to perform the requested
2652 conversion. This function is used for three the overloading situations
2653 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2654 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2655 per [dcl.init.ref], so we ignore temporary bindings. */
2657 static struct z_candidate *
2658 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2660 struct z_candidate *candidates, *cand;
2661 tree fromtype = TREE_TYPE (expr);
2662 tree ctors = NULL_TREE;
2663 tree conv_fns = NULL_TREE;
2664 conversion *conv = NULL;
2665 tree args = NULL_TREE;
2669 /* We represent conversion within a hierarchy using RVALUE_CONV and
2670 BASE_CONV, as specified by [over.best.ics]; these become plain
2671 constructor calls, as specified in [dcl.init]. */
2672 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2673 || !DERIVED_FROM_P (totype, fromtype));
2675 if (MAYBE_CLASS_TYPE_P (totype))
2676 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2678 if (MAYBE_CLASS_TYPE_P (fromtype))
2680 tree to_nonref = non_reference (totype);
2681 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2682 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2683 && DERIVED_FROM_P (to_nonref, fromtype)))
2685 /* [class.conv.fct] A conversion function is never used to
2686 convert a (possibly cv-qualified) object to the (possibly
2687 cv-qualified) same object type (or a reference to it), to a
2688 (possibly cv-qualified) base class of that type (or a
2689 reference to it)... */
2692 conv_fns = lookup_conversions (fromtype);
2696 flags |= LOOKUP_NO_CONVERSION;
2698 /* It's OK to bind a temporary for converting constructor arguments, but
2699 not in converting the return value of a conversion operator. */
2700 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2701 flags &= ~LOOKUP_NO_TEMP_BIND;
2707 ctors = BASELINK_FUNCTIONS (ctors);
2709 t = build_int_cst (build_pointer_type (totype), 0);
2710 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2711 && !TYPE_HAS_LIST_CTOR (totype))
2713 args = ctor_to_list (expr);
2714 /* We still allow more conversions within an init-list. */
2715 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2716 /* But not for the copy ctor. */
2717 |LOOKUP_NO_COPY_CTOR_CONVERSION
2718 |LOOKUP_NO_NARROWING);
2721 args = build_tree_list (NULL_TREE, expr);
2722 /* We should never try to call the abstract or base constructor
2724 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2725 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2726 args = tree_cons (NULL_TREE, t, args);
2728 for (; ctors; ctors = OVL_NEXT (ctors))
2730 tree ctor = OVL_CURRENT (ctors);
2731 if (DECL_NONCONVERTING_P (ctor)
2732 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2735 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2736 cand = add_template_candidate (&candidates, ctor, totype,
2737 NULL_TREE, args, NULL_TREE,
2738 TYPE_BINFO (totype),
2739 TYPE_BINFO (totype),
2743 cand = add_function_candidate (&candidates, ctor, totype,
2744 args, TYPE_BINFO (totype),
2745 TYPE_BINFO (totype),
2750 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2752 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2753 set, then this is copy-initialization. In that case, "The
2754 result of the call is then used to direct-initialize the
2755 object that is the destination of the copy-initialization."
2758 We represent this in the conversion sequence with an
2759 rvalue conversion, which means a constructor call. */
2760 if (TREE_CODE (totype) != REFERENCE_TYPE
2761 && !(convflags & LOOKUP_NO_TEMP_BIND))
2763 = build_conv (ck_rvalue, totype, cand->second_conv);
2768 args = build_tree_list (NULL_TREE, build_this (expr));
2770 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2773 tree conversion_path = TREE_PURPOSE (conv_fns);
2775 /* If we are called to convert to a reference type, we are trying to
2776 find an lvalue binding, so don't even consider temporaries. If
2777 we don't find an lvalue binding, the caller will try again to
2778 look for a temporary binding. */
2779 if (TREE_CODE (totype) == REFERENCE_TYPE)
2780 convflags |= LOOKUP_NO_TEMP_BIND;
2782 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2784 tree fn = OVL_CURRENT (fns);
2786 /* [over.match.funcs] For conversion functions, the function
2787 is considered to be a member of the class of the implicit
2788 object argument for the purpose of defining the type of
2789 the implicit object parameter.
2791 So we pass fromtype as CTYPE to add_*_candidate. */
2793 if (TREE_CODE (fn) == TEMPLATE_DECL)
2794 cand = add_template_candidate (&candidates, fn, fromtype,
2797 TYPE_BINFO (fromtype),
2802 cand = add_function_candidate (&candidates, fn, fromtype,
2804 TYPE_BINFO (fromtype),
2811 = implicit_conversion (totype,
2812 TREE_TYPE (TREE_TYPE (cand->fn)),
2814 /*c_cast_p=*/false, convflags);
2816 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2817 copy-initialization. In that case, "The result of the
2818 call is then used to direct-initialize the object that is
2819 the destination of the copy-initialization." [dcl.init]
2821 We represent this in the conversion sequence with an
2822 rvalue conversion, which means a constructor call. But
2823 don't add a second rvalue conversion if there's already
2824 one there. Which there really shouldn't be, but it's
2825 harmless since we'd add it here anyway. */
2826 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2827 && !(convflags & LOOKUP_NO_TEMP_BIND))
2828 ics = build_conv (ck_rvalue, totype, ics);
2830 cand->second_conv = ics;
2834 else if (candidates->viable == 1 && ics->bad_p)
2840 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2844 cand = tourney (candidates);
2847 if (flags & LOOKUP_COMPLAIN)
2849 error ("conversion from %qT to %qT is ambiguous",
2851 print_z_candidates (candidates);
2854 cand = candidates; /* any one will do */
2855 cand->second_conv = build_ambiguous_conv (totype, expr);
2856 cand->second_conv->user_conv_p = true;
2857 if (!any_strictly_viable (candidates))
2858 cand->second_conv->bad_p = true;
2859 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2860 ambiguous conversion is no worse than another user-defined
2866 /* Build the user conversion sequence. */
2869 (DECL_CONSTRUCTOR_P (cand->fn)
2870 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2871 build_identity_conv (TREE_TYPE (expr), expr));
2874 /* Remember that this was a list-initialization. */
2875 if (flags & LOOKUP_NO_NARROWING)
2876 conv->check_narrowing = true;
2878 /* Combine it with the second conversion sequence. */
2879 cand->second_conv = merge_conversion_sequences (conv,
2882 if (cand->viable == -1)
2883 cand->second_conv->bad_p = true;
2889 build_user_type_conversion (tree totype, tree expr, int flags)
2891 struct z_candidate *cand
2892 = build_user_type_conversion_1 (totype, expr, flags);
2896 if (cand->second_conv->kind == ck_ambig)
2897 return error_mark_node;
2898 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
2899 return convert_from_reference (expr);
2904 /* Do any initial processing on the arguments to a function call. */
2907 resolve_args (tree args)
2910 for (t = args; t; t = TREE_CHAIN (t))
2912 tree arg = TREE_VALUE (t);
2914 if (error_operand_p (arg))
2915 return error_mark_node;
2916 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2918 error ("invalid use of void expression");
2919 return error_mark_node;
2921 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
2922 return error_mark_node;
2927 /* Perform overload resolution on FN, which is called with the ARGS.
2929 Return the candidate function selected by overload resolution, or
2930 NULL if the event that overload resolution failed. In the case
2931 that overload resolution fails, *CANDIDATES will be the set of
2932 candidates considered, and ANY_VIABLE_P will be set to true or
2933 false to indicate whether or not any of the candidates were
2936 The ARGS should already have gone through RESOLVE_ARGS before this
2937 function is called. */
2939 static struct z_candidate *
2940 perform_overload_resolution (tree fn,
2942 struct z_candidate **candidates,
2945 struct z_candidate *cand;
2946 tree explicit_targs = NULL_TREE;
2947 int template_only = 0;
2950 *any_viable_p = true;
2952 /* Check FN and ARGS. */
2953 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2954 || TREE_CODE (fn) == TEMPLATE_DECL
2955 || TREE_CODE (fn) == OVERLOAD
2956 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2957 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2959 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2961 explicit_targs = TREE_OPERAND (fn, 1);
2962 fn = TREE_OPERAND (fn, 0);
2966 /* Add the various candidate functions. */
2967 add_candidates (fn, args, explicit_targs, template_only,
2968 /*conversion_path=*/NULL_TREE,
2969 /*access_path=*/NULL_TREE,
2973 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2977 cand = tourney (*candidates);
2981 /* Return an expression for a call to FN (a namespace-scope function,
2982 or a static member function) with the ARGS. */
2985 build_new_function_call (tree fn, tree args, bool koenig_p,
2986 tsubst_flags_t complain)
2988 struct z_candidate *candidates, *cand;
2993 args = resolve_args (args);
2994 if (args == error_mark_node)
2995 return error_mark_node;
2997 /* If this function was found without using argument dependent
2998 lookup, then we want to ignore any undeclared friend
3004 fn = remove_hidden_names (fn);
3007 if (complain & tf_error)
3008 error ("no matching function for call to %<%D(%A)%>",
3009 DECL_NAME (OVL_CURRENT (orig_fn)), args);
3010 return error_mark_node;
3014 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3015 p = conversion_obstack_alloc (0);
3017 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
3021 if (complain & tf_error)
3023 if (!any_viable_p && candidates && ! candidates->next)
3024 return cp_build_function_call (candidates->fn, args, complain);
3025 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3026 fn = TREE_OPERAND (fn, 0);
3028 error ("no matching function for call to %<%D(%A)%>",
3029 DECL_NAME (OVL_CURRENT (fn)), args);
3031 error ("call of overloaded %<%D(%A)%> is ambiguous",
3032 DECL_NAME (OVL_CURRENT (fn)), args);
3034 print_z_candidates (candidates);
3036 result = error_mark_node;
3039 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3041 /* Free all the conversions we allocated. */
3042 obstack_free (&conversion_obstack, p);
3047 /* Build a call to a global operator new. FNNAME is the name of the
3048 operator (either "operator new" or "operator new[]") and ARGS are
3049 the arguments provided. *SIZE points to the total number of bytes
3050 required by the allocation, and is updated if that is changed here.
3051 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
3052 function determines that no cookie should be used, after all,
3053 *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be
3054 set, upon return, to the allocation function called. */
3057 build_operator_new_call (tree fnname, tree args,
3058 tree *size, tree *cookie_size,
3062 struct z_candidate *candidates;
3063 struct z_candidate *cand;
3068 args = tree_cons (NULL_TREE, *size, args);
3069 args = resolve_args (args);
3070 if (args == error_mark_node)
3077 If this lookup fails to find the name, or if the allocated type
3078 is not a class type, the allocation function's name is looked
3079 up in the global scope.
3081 we disregard block-scope declarations of "operator new". */
3082 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
3084 /* Figure out what function is being called. */
3085 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
3087 /* If no suitable function could be found, issue an error message
3092 error ("no matching function for call to %<%D(%A)%>",
3093 DECL_NAME (OVL_CURRENT (fns)), args);
3095 error ("call of overloaded %<%D(%A)%> is ambiguous",
3096 DECL_NAME (OVL_CURRENT (fns)), args);
3098 print_z_candidates (candidates);
3099 return error_mark_node;
3102 /* If a cookie is required, add some extra space. Whether
3103 or not a cookie is required cannot be determined until
3104 after we know which function was called. */
3107 bool use_cookie = true;
3108 if (!abi_version_at_least (2))
3110 tree placement = TREE_CHAIN (args);
3111 /* In G++ 3.2, the check was implemented incorrectly; it
3112 looked at the placement expression, rather than the
3113 type of the function. */
3114 if (placement && !TREE_CHAIN (placement)
3115 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
3123 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3124 /* Skip the size_t parameter. */
3125 arg_types = TREE_CHAIN (arg_types);
3126 /* Check the remaining parameters (if any). */
3128 && TREE_CHAIN (arg_types) == void_list_node
3129 && same_type_p (TREE_VALUE (arg_types),
3133 /* If we need a cookie, adjust the number of bytes allocated. */
3136 /* Update the total size. */
3137 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3138 /* Update the argument list to reflect the adjusted size. */
3139 TREE_VALUE (args) = *size;
3142 *cookie_size = NULL_TREE;
3145 /* Tell our caller which function we decided to call. */
3149 /* Build the CALL_EXPR. */
3150 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3154 build_object_call (tree obj, tree args, tsubst_flags_t complain)
3156 struct z_candidate *candidates = 0, *cand;
3157 tree fns, convs, mem_args = NULL_TREE;
3158 tree type = TREE_TYPE (obj);
3160 tree result = NULL_TREE;
3163 if (TYPE_PTRMEMFUNC_P (type))
3165 if (complain & tf_error)
3166 /* It's no good looking for an overloaded operator() on a
3167 pointer-to-member-function. */
3168 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3169 return error_mark_node;
3172 if (TYPE_BINFO (type))
3174 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3175 if (fns == error_mark_node)
3176 return error_mark_node;
3181 args = resolve_args (args);
3183 if (args == error_mark_node)
3184 return error_mark_node;
3186 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3187 p = conversion_obstack_alloc (0);
3191 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3192 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
3194 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3196 tree fn = OVL_CURRENT (fns);
3197 if (TREE_CODE (fn) == TEMPLATE_DECL)
3198 add_template_candidate (&candidates, fn, base, NULL_TREE,
3199 mem_args, NULL_TREE,
3202 LOOKUP_NORMAL, DEDUCE_CALL);
3204 add_function_candidate
3205 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
3206 TYPE_BINFO (type), LOOKUP_NORMAL);
3210 convs = lookup_conversions (type);
3212 for (; convs; convs = TREE_CHAIN (convs))
3214 tree fns = TREE_VALUE (convs);
3215 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
3217 if ((TREE_CODE (totype) == POINTER_TYPE
3218 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3219 || (TREE_CODE (totype) == REFERENCE_TYPE
3220 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3221 || (TREE_CODE (totype) == REFERENCE_TYPE
3222 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3223 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3224 for (; fns; fns = OVL_NEXT (fns))
3226 tree fn = OVL_CURRENT (fns);
3227 if (TREE_CODE (fn) == TEMPLATE_DECL)
3228 add_template_conv_candidate
3229 (&candidates, fn, obj, args, totype,
3230 /*access_path=*/NULL_TREE,
3231 /*conversion_path=*/NULL_TREE);
3233 add_conv_candidate (&candidates, fn, obj, args,
3234 /*conversion_path=*/NULL_TREE,
3235 /*access_path=*/NULL_TREE);
3239 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3242 if (complain & tf_error)
3244 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3245 print_z_candidates (candidates);
3247 result = error_mark_node;
3251 cand = tourney (candidates);
3254 if (complain & tf_error)
3256 error ("call of %<(%T) (%A)%> is ambiguous",
3257 TREE_TYPE (obj), args);
3258 print_z_candidates (candidates);
3260 result = error_mark_node;
3262 /* Since cand->fn will be a type, not a function, for a conversion
3263 function, we must be careful not to unconditionally look at
3265 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3266 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3267 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3270 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3272 obj = convert_from_reference (obj);
3273 result = cp_build_function_call (obj, args, complain);
3277 /* Free all the conversions we allocated. */
3278 obstack_free (&conversion_obstack, p);
3284 op_error (enum tree_code code, enum tree_code code2,
3285 tree arg1, tree arg2, tree arg3, const char *problem)
3289 if (code == MODIFY_EXPR)
3290 opname = assignment_operator_name_info[code2].name;
3292 opname = operator_name_info[code].name;
3297 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3298 problem, arg1, arg2, arg3);
3301 case POSTINCREMENT_EXPR:
3302 case POSTDECREMENT_EXPR:
3303 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3307 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3312 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3317 error ("%s for %<operator%s%> in %<%E %s %E%>",
3318 problem, opname, arg1, opname, arg2);
3320 error ("%s for %<operator%s%> in %<%s%E%>",
3321 problem, opname, opname, arg1);
3326 /* Return the implicit conversion sequence that could be used to
3327 convert E1 to E2 in [expr.cond]. */
3330 conditional_conversion (tree e1, tree e2)
3332 tree t1 = non_reference (TREE_TYPE (e1));
3333 tree t2 = non_reference (TREE_TYPE (e2));
3339 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3340 implicitly converted (clause _conv_) to the type "reference to
3341 T2", subject to the constraint that in the conversion the
3342 reference must bind directly (_dcl.init.ref_) to E1. */
3343 if (real_lvalue_p (e2))
3345 conv = implicit_conversion (build_reference_type (t2),
3349 LOOKUP_NO_TEMP_BIND);
3356 If E1 and E2 have class type, and the underlying class types are
3357 the same or one is a base class of the other: E1 can be converted
3358 to match E2 if the class of T2 is the same type as, or a base
3359 class of, the class of T1, and the cv-qualification of T2 is the
3360 same cv-qualification as, or a greater cv-qualification than, the
3361 cv-qualification of T1. If the conversion is applied, E1 is
3362 changed to an rvalue of type T2 that still refers to the original
3363 source class object (or the appropriate subobject thereof). */
3364 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3365 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3367 if (good_base && at_least_as_qualified_p (t2, t1))
3369 conv = build_identity_conv (t1, e1);
3370 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3371 TYPE_MAIN_VARIANT (t2)))
3372 conv = build_conv (ck_base, t2, conv);
3374 conv = build_conv (ck_rvalue, t2, conv);
3383 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3384 converted to the type that expression E2 would have if E2 were
3385 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3386 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3390 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3391 arguments to the conditional expression. */
3394 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3395 tsubst_flags_t complain)
3399 tree result = NULL_TREE;
3400 tree result_type = NULL_TREE;
3401 bool lvalue_p = true;
3402 struct z_candidate *candidates = 0;
3403 struct z_candidate *cand;
3406 /* As a G++ extension, the second argument to the conditional can be
3407 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3408 c'.) If the second operand is omitted, make sure it is
3409 calculated only once. */
3412 if (complain & tf_error)
3413 pedwarn (input_location, OPT_pedantic,
3414 "ISO C++ forbids omitting the middle term of a ?: expression");
3416 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3417 if (real_lvalue_p (arg1))
3418 arg2 = arg1 = stabilize_reference (arg1);
3420 arg2 = arg1 = save_expr (arg1);
3425 The first expression is implicitly converted to bool (clause
3427 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3429 /* If something has already gone wrong, just pass that fact up the
3431 if (error_operand_p (arg1)
3432 || error_operand_p (arg2)
3433 || error_operand_p (arg3))
3434 return error_mark_node;
3438 If either the second or the third operand has type (possibly
3439 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3440 array-to-pointer (_conv.array_), and function-to-pointer
3441 (_conv.func_) standard conversions are performed on the second
3442 and third operands. */
3443 arg2_type = unlowered_expr_type (arg2);
3444 arg3_type = unlowered_expr_type (arg3);
3445 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3447 /* Do the conversions. We don't these for `void' type arguments
3448 since it can't have any effect and since decay_conversion
3449 does not handle that case gracefully. */
3450 if (!VOID_TYPE_P (arg2_type))
3451 arg2 = decay_conversion (arg2);
3452 if (!VOID_TYPE_P (arg3_type))
3453 arg3 = decay_conversion (arg3);
3454 arg2_type = TREE_TYPE (arg2);
3455 arg3_type = TREE_TYPE (arg3);
3459 One of the following shall hold:
3461 --The second or the third operand (but not both) is a
3462 throw-expression (_except.throw_); the result is of the
3463 type of the other and is an rvalue.
3465 --Both the second and the third operands have type void; the
3466 result is of type void and is an rvalue.
3468 We must avoid calling force_rvalue for expressions of type
3469 "void" because it will complain that their value is being
3471 if (TREE_CODE (arg2) == THROW_EXPR
3472 && TREE_CODE (arg3) != THROW_EXPR)
3474 if (!VOID_TYPE_P (arg3_type))
3475 arg3 = force_rvalue (arg3);
3476 arg3_type = TREE_TYPE (arg3);
3477 result_type = arg3_type;
3479 else if (TREE_CODE (arg2) != THROW_EXPR
3480 && TREE_CODE (arg3) == THROW_EXPR)
3482 if (!VOID_TYPE_P (arg2_type))
3483 arg2 = force_rvalue (arg2);
3484 arg2_type = TREE_TYPE (arg2);
3485 result_type = arg2_type;
3487 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3488 result_type = void_type_node;
3491 if (complain & tf_error)
3493 if (VOID_TYPE_P (arg2_type))
3494 error ("second operand to the conditional operator "
3495 "is of type %<void%>, "
3496 "but the third operand is neither a throw-expression "
3497 "nor of type %<void%>");
3499 error ("third operand to the conditional operator "
3500 "is of type %<void%>, "
3501 "but the second operand is neither a throw-expression "
3502 "nor of type %<void%>");
3504 return error_mark_node;
3508 goto valid_operands;
3512 Otherwise, if the second and third operand have different types,
3513 and either has (possibly cv-qualified) class type, an attempt is
3514 made to convert each of those operands to the type of the other. */
3515 else if (!same_type_p (arg2_type, arg3_type)
3516 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3521 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3522 p = conversion_obstack_alloc (0);
3524 conv2 = conditional_conversion (arg2, arg3);
3525 conv3 = conditional_conversion (arg3, arg2);
3529 If both can be converted, or one can be converted but the
3530 conversion is ambiguous, the program is ill-formed. If
3531 neither can be converted, the operands are left unchanged and
3532 further checking is performed as described below. If exactly
3533 one conversion is possible, that conversion is applied to the
3534 chosen operand and the converted operand is used in place of
3535 the original operand for the remainder of this section. */
3536 if ((conv2 && !conv2->bad_p
3537 && conv3 && !conv3->bad_p)
3538 || (conv2 && conv2->kind == ck_ambig)
3539 || (conv3 && conv3->kind == ck_ambig))
3541 error ("operands to ?: have different types %qT and %qT",
3542 arg2_type, arg3_type);
3543 result = error_mark_node;
3545 else if (conv2 && (!conv2->bad_p || !conv3))
3547 arg2 = convert_like (conv2, arg2, complain);
3548 arg2 = convert_from_reference (arg2);
3549 arg2_type = TREE_TYPE (arg2);
3550 /* Even if CONV2 is a valid conversion, the result of the
3551 conversion may be invalid. For example, if ARG3 has type
3552 "volatile X", and X does not have a copy constructor
3553 accepting a "volatile X&", then even if ARG2 can be
3554 converted to X, the conversion will fail. */
3555 if (error_operand_p (arg2))
3556 result = error_mark_node;
3558 else if (conv3 && (!conv3->bad_p || !conv2))
3560 arg3 = convert_like (conv3, arg3, complain);
3561 arg3 = convert_from_reference (arg3);
3562 arg3_type = TREE_TYPE (arg3);
3563 if (error_operand_p (arg3))
3564 result = error_mark_node;
3567 /* Free all the conversions we allocated. */
3568 obstack_free (&conversion_obstack, p);
3573 /* If, after the conversion, both operands have class type,
3574 treat the cv-qualification of both operands as if it were the
3575 union of the cv-qualification of the operands.
3577 The standard is not clear about what to do in this
3578 circumstance. For example, if the first operand has type
3579 "const X" and the second operand has a user-defined
3580 conversion to "volatile X", what is the type of the second
3581 operand after this step? Making it be "const X" (matching
3582 the first operand) seems wrong, as that discards the
3583 qualification without actually performing a copy. Leaving it
3584 as "volatile X" seems wrong as that will result in the
3585 conditional expression failing altogether, even though,
3586 according to this step, the one operand could be converted to
3587 the type of the other. */
3588 if ((conv2 || conv3)
3589 && CLASS_TYPE_P (arg2_type)
3590 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3591 arg2_type = arg3_type =
3592 cp_build_qualified_type (arg2_type,
3593 TYPE_QUALS (arg2_type)
3594 | TYPE_QUALS (arg3_type));
3599 If the second and third operands are lvalues and have the same
3600 type, the result is of that type and is an lvalue. */
3601 if (real_lvalue_p (arg2)
3602 && real_lvalue_p (arg3)
3603 && same_type_p (arg2_type, arg3_type))
3605 result_type = arg2_type;
3606 goto valid_operands;
3611 Otherwise, the result is an rvalue. If the second and third
3612 operand do not have the same type, and either has (possibly
3613 cv-qualified) class type, overload resolution is used to
3614 determine the conversions (if any) to be applied to the operands
3615 (_over.match.oper_, _over.built_). */
3617 if (!same_type_p (arg2_type, arg3_type)
3618 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3624 /* Rearrange the arguments so that add_builtin_candidate only has
3625 to know about two args. In build_builtin_candidates, the
3626 arguments are unscrambled. */
3630 add_builtin_candidates (&candidates,
3633 ansi_opname (COND_EXPR),
3639 If the overload resolution fails, the program is
3641 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3644 if (complain & tf_error)
3646 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3647 print_z_candidates (candidates);
3649 return error_mark_node;
3651 cand = tourney (candidates);
3654 if (complain & tf_error)
3656 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3657 print_z_candidates (candidates);
3659 return error_mark_node;
3664 Otherwise, the conversions thus determined are applied, and
3665 the converted operands are used in place of the original
3666 operands for the remainder of this section. */
3667 conv = cand->convs[0];
3668 arg1 = convert_like (conv, arg1, complain);
3669 conv = cand->convs[1];
3670 arg2 = convert_like (conv, arg2, complain);
3671 conv = cand->convs[2];
3672 arg3 = convert_like (conv, arg3, complain);
3677 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3678 and function-to-pointer (_conv.func_) standard conversions are
3679 performed on the second and third operands.
3681 We need to force the lvalue-to-rvalue conversion here for class types,
3682 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3683 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3686 arg2 = force_rvalue (arg2);
3687 if (!CLASS_TYPE_P (arg2_type))
3688 arg2_type = TREE_TYPE (arg2);
3690 arg3 = force_rvalue (arg3);
3691 if (!CLASS_TYPE_P (arg2_type))
3692 arg3_type = TREE_TYPE (arg3);
3694 if (arg2 == error_mark_node || arg3 == error_mark_node)
3695 return error_mark_node;
3699 After those conversions, one of the following shall hold:
3701 --The second and third operands have the same type; the result is of
3703 if (same_type_p (arg2_type, arg3_type))
3704 result_type = arg2_type;
3707 --The second and third operands have arithmetic or enumeration
3708 type; the usual arithmetic conversions are performed to bring
3709 them to a common type, and the result is of that type. */
3710 else if ((ARITHMETIC_TYPE_P (arg2_type)
3711 || UNSCOPED_ENUM_P (arg2_type))
3712 && (ARITHMETIC_TYPE_P (arg3_type)
3713 || UNSCOPED_ENUM_P (arg3_type)))
3715 /* In this case, there is always a common type. */
3716 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3719 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3720 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3722 if (complain & tf_warning)
3724 "enumeral mismatch in conditional expression: %qT vs %qT",
3725 arg2_type, arg3_type);
3727 else if (extra_warnings
3728 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3729 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3730 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3731 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3733 if (complain & tf_warning)
3735 "enumeral and non-enumeral type in conditional expression");
3738 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3739 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3743 --The second and third operands have pointer type, or one has
3744 pointer type and the other is a null pointer constant; pointer
3745 conversions (_conv.ptr_) and qualification conversions
3746 (_conv.qual_) are performed to bring them to their composite
3747 pointer type (_expr.rel_). The result is of the composite
3750 --The second and third operands have pointer to member type, or
3751 one has pointer to member type and the other is a null pointer
3752 constant; pointer to member conversions (_conv.mem_) and
3753 qualification conversions (_conv.qual_) are performed to bring
3754 them to a common type, whose cv-qualification shall match the
3755 cv-qualification of either the second or the third operand.
3756 The result is of the common type. */
3757 else if ((null_ptr_cst_p (arg2)
3758 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3759 || (null_ptr_cst_p (arg3)
3760 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3761 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3762 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3763 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3765 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3766 arg3, "conditional expression",
3768 if (result_type == error_mark_node)
3769 return error_mark_node;
3770 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3771 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3776 if (complain & tf_error)
3777 error ("operands to ?: have different types %qT and %qT",
3778 arg2_type, arg3_type);
3779 return error_mark_node;
3783 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3785 /* We can't use result_type below, as fold might have returned a
3790 /* Expand both sides into the same slot, hopefully the target of
3791 the ?: expression. We used to check for TARGET_EXPRs here,
3792 but now we sometimes wrap them in NOP_EXPRs so the test would
3794 if (CLASS_TYPE_P (TREE_TYPE (result)))
3795 result = get_target_expr (result);
3796 /* If this expression is an rvalue, but might be mistaken for an
3797 lvalue, we must add a NON_LVALUE_EXPR. */
3798 result = rvalue (result);
3804 /* OPERAND is an operand to an expression. Perform necessary steps
3805 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3809 prep_operand (tree operand)
3813 if (CLASS_TYPE_P (TREE_TYPE (operand))
3814 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3815 /* Make sure the template type is instantiated now. */
3816 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3822 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3823 OVERLOAD) to the CANDIDATES, returning an updated list of
3824 CANDIDATES. The ARGS are the arguments provided to the call,
3825 without any implicit object parameter. The EXPLICIT_TARGS are
3826 explicit template arguments provided. TEMPLATE_ONLY is true if
3827 only template functions should be considered. CONVERSION_PATH,
3828 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3831 add_candidates (tree fns, tree args,
3832 tree explicit_targs, bool template_only,
3833 tree conversion_path, tree access_path,
3835 struct z_candidate **candidates)
3838 tree non_static_args;
3840 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3841 /* Delay creating the implicit this parameter until it is needed. */
3842 non_static_args = NULL_TREE;
3849 fn = OVL_CURRENT (fns);
3850 /* Figure out which set of arguments to use. */
3851 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3853 /* If this function is a non-static member, prepend the implicit
3854 object parameter. */
3855 if (!non_static_args)
3856 non_static_args = tree_cons (NULL_TREE,
3857 build_this (TREE_VALUE (args)),
3859 fn_args = non_static_args;
3862 /* Otherwise, just use the list of arguments provided. */
3865 if (TREE_CODE (fn) == TEMPLATE_DECL)
3866 add_template_candidate (candidates,
3876 else if (!template_only)
3877 add_function_candidate (candidates,
3884 fns = OVL_NEXT (fns);
3889 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3890 bool *overloaded_p, tsubst_flags_t complain)
3892 struct z_candidate *candidates = 0, *cand;
3893 tree arglist, fnname;
3895 tree result = NULL_TREE;
3896 bool result_valid_p = false;
3897 enum tree_code code2 = NOP_EXPR;
3902 bool expl_eq_arg1 = false;
3904 if (error_operand_p (arg1)
3905 || error_operand_p (arg2)
3906 || error_operand_p (arg3))
3907 return error_mark_node;
3909 if (code == MODIFY_EXPR)
3911 code2 = TREE_CODE (arg3);
3913 fnname = ansi_assopname (code2);
3916 fnname = ansi_opname (code);
3918 arg1 = prep_operand (arg1);
3924 case VEC_DELETE_EXPR:
3926 /* Use build_op_new_call and build_op_delete_call instead. */
3930 return build_object_call (arg1, arg2, complain);
3932 case TRUTH_ORIF_EXPR:
3933 case TRUTH_ANDIF_EXPR:
3934 case TRUTH_AND_EXPR:
3936 if (COMPARISON_CLASS_P (arg1))
3937 expl_eq_arg1 = true;
3942 arg2 = prep_operand (arg2);
3943 arg3 = prep_operand (arg3);
3945 if (code == COND_EXPR)
3947 if (arg2 == NULL_TREE
3948 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3949 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3950 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3951 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3954 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3955 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3958 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3959 arg2 = integer_zero_node;
3961 arglist = NULL_TREE;
3963 arglist = tree_cons (NULL_TREE, arg3, arglist);
3965 arglist = tree_cons (NULL_TREE, arg2, arglist);
3966 arglist = tree_cons (NULL_TREE, arg1, arglist);
3968 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3969 p = conversion_obstack_alloc (0);
3971 /* Add namespace-scope operators to the list of functions to
3973 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3974 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3975 flags, &candidates);
3976 /* Add class-member operators to the candidate set. */
3977 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3981 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3982 if (fns == error_mark_node)
3984 result = error_mark_node;
3985 goto user_defined_result_ready;
3988 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3990 BASELINK_BINFO (fns),
3991 TYPE_BINFO (TREE_TYPE (arg1)),
3992 flags, &candidates);
3995 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3996 to know about two args; a builtin candidate will always have a first
3997 parameter of type bool. We'll handle that in
3998 build_builtin_candidate. */
3999 if (code == COND_EXPR)
4009 args[2] = NULL_TREE;
4012 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4018 /* For these, the built-in candidates set is empty
4019 [over.match.oper]/3. We don't want non-strict matches
4020 because exact matches are always possible with built-in
4021 operators. The built-in candidate set for COMPONENT_REF
4022 would be empty too, but since there are no such built-in
4023 operators, we accept non-strict matches for them. */
4028 strict_p = pedantic;
4032 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4037 case POSTINCREMENT_EXPR:
4038 case POSTDECREMENT_EXPR:
4039 /* Don't try anything fancy if we're not allowed to produce
4041 if (!(complain & tf_error))
4042 return error_mark_node;
4044 /* Look for an `operator++ (int)'. If they didn't have
4045 one, then we fall back to the old way of doing things. */
4046 if (flags & LOOKUP_COMPLAIN)
4047 permerror (input_location, "no %<%D(int)%> declared for postfix %qs, "
4048 "trying prefix operator instead",
4050 operator_name_info[code].name);
4051 if (code == POSTINCREMENT_EXPR)
4052 code = PREINCREMENT_EXPR;
4054 code = PREDECREMENT_EXPR;
4055 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4056 overloaded_p, complain);
4059 /* The caller will deal with these. */
4064 result_valid_p = true;
4068 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4070 op_error (code, code2, arg1, arg2, arg3, "no match");
4071 print_z_candidates (candidates);
4073 result = error_mark_node;
4079 cand = tourney (candidates);
4082 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4084 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4085 print_z_candidates (candidates);
4087 result = error_mark_node;
4089 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4092 *overloaded_p = true;
4094 if (resolve_args (arglist) == error_mark_node)
4095 result = error_mark_node;
4097 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4101 /* Give any warnings we noticed during overload resolution. */
4102 if (cand->warnings && (complain & tf_warning))
4104 struct candidate_warning *w;
4105 for (w = cand->warnings; w; w = w->next)
4106 joust (cand, w->loser, 1);
4109 /* Check for comparison of different enum types. */
4118 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4119 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4120 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4121 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4122 && (complain & tf_warning))
4124 warning (OPT_Wenum_compare,
4125 "comparison between %q#T and %q#T",
4126 TREE_TYPE (arg1), TREE_TYPE (arg2));
4133 /* We need to strip any leading REF_BIND so that bitfields
4134 don't cause errors. This should not remove any important
4135 conversions, because builtins don't apply to class
4136 objects directly. */
4137 conv = cand->convs[0];
4138 if (conv->kind == ck_ref_bind)
4139 conv = conv->u.next;
4140 arg1 = convert_like (conv, arg1, complain);
4143 conv = cand->convs[1];
4144 if (conv->kind == ck_ref_bind)
4145 conv = conv->u.next;
4146 arg2 = convert_like (conv, arg2, complain);
4150 conv = cand->convs[2];
4151 if (conv->kind == ck_ref_bind)
4152 conv = conv->u.next;
4153 arg3 = convert_like (conv, arg3, complain);
4158 if (complain & tf_warning)
4159 warn_logical_operator (code, arg1, arg2);
4160 expl_eq_arg1 = true;
4165 user_defined_result_ready:
4167 /* Free all the conversions we allocated. */
4168 obstack_free (&conversion_obstack, p);
4170 if (result || result_valid_p)
4177 return cp_build_modify_expr (arg1, code2, arg2, complain);
4180 return cp_build_indirect_ref (arg1, "unary *", complain);
4182 case TRUTH_ANDIF_EXPR:
4183 case TRUTH_ORIF_EXPR:
4184 case TRUTH_AND_EXPR:
4187 warn_logical_operator (code, arg1, arg2);
4191 case TRUNC_DIV_EXPR:
4202 case TRUNC_MOD_EXPR:
4206 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4208 case UNARY_PLUS_EXPR:
4211 case TRUTH_NOT_EXPR:
4212 case PREINCREMENT_EXPR:
4213 case POSTINCREMENT_EXPR:
4214 case PREDECREMENT_EXPR:
4215 case POSTDECREMENT_EXPR:
4218 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4221 return build_array_ref (arg1, arg2, input_location);
4224 return build_conditional_expr (arg1, arg2, arg3, complain);
4227 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4231 /* The caller will deal with these. */
4243 /* Build a call to operator delete. This has to be handled very specially,
4244 because the restrictions on what signatures match are different from all
4245 other call instances. For a normal delete, only a delete taking (void *)
4246 or (void *, size_t) is accepted. For a placement delete, only an exact
4247 match with the placement new is accepted.
4249 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4250 ADDR is the pointer to be deleted.
4251 SIZE is the size of the memory block to be deleted.
4252 GLOBAL_P is true if the delete-expression should not consider
4253 class-specific delete operators.
4254 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4256 If this call to "operator delete" is being generated as part to
4257 deallocate memory allocated via a new-expression (as per [expr.new]
4258 which requires that if the initialization throws an exception then
4259 we call a deallocation function), then ALLOC_FN is the allocation
4263 build_op_delete_call (enum tree_code code, tree addr, tree size,
4264 bool global_p, tree placement,
4267 tree fn = NULL_TREE;
4268 tree fns, fnname, argtypes, type;
4271 if (addr == error_mark_node)
4272 return error_mark_node;
4274 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4276 fnname = ansi_opname (code);
4278 if (CLASS_TYPE_P (type)
4279 && COMPLETE_TYPE_P (complete_type (type))
4283 If the result of the lookup is ambiguous or inaccessible, or if
4284 the lookup selects a placement deallocation function, the
4285 program is ill-formed.
4287 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4289 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4290 if (fns == error_mark_node)
4291 return error_mark_node;
4296 if (fns == NULL_TREE)
4297 fns = lookup_name_nonclass (fnname);
4299 /* Strip const and volatile from addr. */
4300 addr = cp_convert (ptr_type_node, addr);
4304 /* Get the parameter types for the allocation function that is
4306 gcc_assert (alloc_fn != NULL_TREE);
4307 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4311 /* First try it without the size argument. */
4312 argtypes = void_list_node;
4315 /* We make two tries at finding a matching `operator delete'. On
4316 the first pass, we look for a one-operator (or placement)
4317 operator delete. If we're not doing placement delete, then on
4318 the second pass we look for a two-argument delete. */
4319 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4321 /* Go through the `operator delete' functions looking for one
4322 with a matching type. */
4323 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4329 /* The first argument must be "void *". */
4330 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4331 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4334 /* On the first pass, check the rest of the arguments. */
4340 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4348 /* On the second pass, look for a function with exactly two
4349 arguments: "void *" and "size_t". */
4351 /* For "operator delete(void *, ...)" there will be
4352 no second argument, but we will not get an exact
4355 && same_type_p (TREE_VALUE (t), size_type_node)
4356 && TREE_CHAIN (t) == void_list_node)
4360 /* If we found a match, we're done. */
4365 /* If we have a matching function, call it. */
4368 /* Make sure we have the actual function, and not an
4370 fn = OVL_CURRENT (fn);
4372 /* If the FN is a member function, make sure that it is
4374 if (DECL_CLASS_SCOPE_P (fn))
4375 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4379 /* The placement args might not be suitable for overload
4380 resolution at this point, so build the call directly. */
4381 int nargs = call_expr_nargs (placement);
4382 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4385 for (i = 1; i < nargs; i++)
4386 argarray[i] = CALL_EXPR_ARG (placement, i);
4388 return build_cxx_call (fn, nargs, argarray);
4394 args = tree_cons (NULL_TREE, addr, NULL_TREE);
4396 args = tree_cons (NULL_TREE, addr,
4397 build_tree_list (NULL_TREE, size));
4398 return cp_build_function_call (fn, args, tf_warning_or_error);
4404 If no unambiguous matching deallocation function can be found,
4405 propagating the exception does not cause the object's memory to
4410 warning (0, "no corresponding deallocation function for %qD",
4415 error ("no suitable %<operator %s%> for %qT",
4416 operator_name_info[(int)code].name, type);
4417 return error_mark_node;
4420 /* If the current scope isn't allowed to access DECL along
4421 BASETYPE_PATH, give an error. The most derived class in
4422 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4423 the declaration to use in the error diagnostic. */
4426 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4428 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4430 if (!accessible_p (basetype_path, decl, true))
4432 if (TREE_PRIVATE (decl))
4433 error ("%q+#D is private", diag_decl);
4434 else if (TREE_PROTECTED (decl))
4435 error ("%q+#D is protected", diag_decl);
4437 error ("%q+#D is inaccessible", diag_decl);
4438 error ("within this context");
4445 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4446 bitwise or of LOOKUP_* values. If any errors are warnings are
4447 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4448 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4452 build_temp (tree expr, tree type, int flags,
4453 diagnostic_t *diagnostic_kind)
4457 savew = warningcount, savee = errorcount;
4458 expr = build_special_member_call (NULL_TREE,
4459 complete_ctor_identifier,
4460 build_tree_list (NULL_TREE, expr),
4461 type, flags, tf_warning_or_error);
4462 if (warningcount > savew)
4463 *diagnostic_kind = DK_WARNING;
4464 else if (errorcount > savee)
4465 *diagnostic_kind = DK_ERROR;
4467 *diagnostic_kind = 0;
4471 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4472 EXPR is implicitly converted to type TOTYPE.
4473 FN and ARGNUM are used for diagnostics. */
4476 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4478 tree t = non_reference (totype);
4480 /* Issue warnings about peculiar, but valid, uses of NULL. */
4481 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4484 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4487 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4490 /* Issue warnings if "false" is converted to a NULL pointer */
4491 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4492 warning (OPT_Wconversion,
4493 "converting %<false%> to pointer type for argument %P of %qD",
4497 /* Perform the conversions in CONVS on the expression EXPR. FN and
4498 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4499 indicates the `this' argument of a method. INNER is nonzero when
4500 being called to continue a conversion chain. It is negative when a
4501 reference binding will be applied, positive otherwise. If
4502 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4503 conversions will be emitted if appropriate. If C_CAST_P is true,
4504 this conversion is coming from a C-style cast; in that case,
4505 conversions to inaccessible bases are permitted. */
4508 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4509 int inner, bool issue_conversion_warnings,
4510 bool c_cast_p, tsubst_flags_t complain)
4512 tree totype = convs->type;
4513 diagnostic_t diag_kind;
4517 && convs->kind != ck_user
4518 && convs->kind != ck_ambig
4519 && convs->kind != ck_ref_bind
4520 && convs->kind != ck_rvalue
4521 && convs->kind != ck_base)
4523 conversion *t = convs;
4524 for (; t; t = convs->u.next)
4526 if (t->kind == ck_user || !t->bad_p)
4528 expr = convert_like_real (t, expr, fn, argnum, 1,
4529 /*issue_conversion_warnings=*/false,
4534 else if (t->kind == ck_ambig)
4535 return convert_like_real (t, expr, fn, argnum, 1,
4536 /*issue_conversion_warnings=*/false,
4539 else if (t->kind == ck_identity)
4542 if (complain & tf_error)
4544 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4546 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4549 return error_mark_node;
4551 return cp_convert (totype, expr);
4554 if (issue_conversion_warnings && (complain & tf_warning))
4555 conversion_null_warnings (totype, expr, fn, argnum);
4557 switch (convs->kind)
4561 struct z_candidate *cand = convs->cand;
4562 tree convfn = cand->fn;
4565 /* When converting from an init list we consider explicit
4566 constructors, but actually trying to call one is an error. */
4567 if (DECL_NONCONVERTING_P (convfn))
4569 if (complain & tf_error)
4570 error ("converting to %qT from initializer list would use "
4571 "explicit constructor %qD", totype, convfn);
4573 return error_mark_node;
4576 /* Set user_conv_p on the argument conversions, so rvalue/base
4577 handling knows not to allow any more UDCs. */
4578 for (i = 0; i < cand->num_convs; ++i)
4579 cand->convs[i]->user_conv_p = true;
4581 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4583 /* If this is a constructor or a function returning an aggr type,
4584 we need to build up a TARGET_EXPR. */
4585 if (DECL_CONSTRUCTOR_P (convfn))
4587 expr = build_cplus_new (totype, expr);
4589 /* Remember that this was list-initialization. */
4590 if (convs->check_narrowing)
4591 TARGET_EXPR_LIST_INIT_P (expr) = true;
4597 if (type_unknown_p (expr))
4598 expr = instantiate_type (totype, expr, complain);
4599 /* Convert a constant to its underlying value, unless we are
4600 about to bind it to a reference, in which case we need to
4601 leave it as an lvalue. */
4604 expr = decl_constant_value (expr);
4605 if (expr == null_node && INTEGRAL_TYPE_P (totype))
4606 /* If __null has been converted to an integer type, we do not
4607 want to warn about uses of EXPR as an integer, rather than
4609 expr = build_int_cst (totype, 0);
4613 /* Call build_user_type_conversion again for the error. */
4614 return build_user_type_conversion
4615 (totype, convs->u.expr, LOOKUP_NORMAL);
4619 /* Conversion to std::initializer_list<T>. */
4620 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4621 tree new_ctor = build_constructor (init_list_type_node, NULL);
4622 unsigned len = CONSTRUCTOR_NELTS (expr);
4623 tree array, parms, val;
4626 /* Convert all the elements. */
4627 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4629 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4630 1, false, false, complain);
4631 if (sub == error_mark_node)
4633 check_narrowing (TREE_TYPE (sub), val);
4634 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4636 /* Build up the array. */
4637 elttype = cp_build_qualified_type
4638 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4639 array = build_array_of_n_type (elttype, len);
4640 array = finish_compound_literal (array, new_ctor);
4642 parms = build_tree_list (NULL_TREE, size_int (len));
4643 parms = tree_cons (NULL_TREE, decay_conversion (array), parms);
4644 /* Call the private constructor. */
4645 push_deferring_access_checks (dk_no_check);
4646 new_ctor = build_special_member_call
4647 (NULL_TREE, complete_ctor_identifier, parms, totype, 0, complain);
4648 pop_deferring_access_checks ();
4649 return build_cplus_new (totype, new_ctor);
4653 return get_target_expr (digest_init (totype, expr));
4659 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4660 convs->kind == ck_ref_bind ? -1 : 1,
4661 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4664 if (expr == error_mark_node)
4665 return error_mark_node;
4667 switch (convs->kind)
4670 expr = convert_bitfield_to_declared_type (expr);
4671 if (! MAYBE_CLASS_TYPE_P (totype))
4673 /* Else fall through. */
4675 if (convs->kind == ck_base && !convs->need_temporary_p)
4677 /* We are going to bind a reference directly to a base-class
4678 subobject of EXPR. */
4679 /* Build an expression for `*((base*) &expr)'. */
4680 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4681 expr = convert_to_base (expr, build_pointer_type (totype),
4682 !c_cast_p, /*nonnull=*/true);
4683 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4687 /* Copy-initialization where the cv-unqualified version of the source
4688 type is the same class as, or a derived class of, the class of the
4689 destination [is treated as direct-initialization]. [dcl.init] */
4690 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4691 if (convs->user_conv_p)
4692 /* This conversion is being done in the context of a user-defined
4693 conversion (i.e. the second step of copy-initialization), so
4694 don't allow any more. */
4695 flags |= LOOKUP_NO_CONVERSION;
4696 expr = build_temp (expr, totype, flags, &diag_kind);
4697 if (diag_kind && fn)
4699 if ((complain & tf_error))
4700 emit_diagnostic (diag_kind, input_location, 0,
4701 " initializing argument %P of %qD", argnum, fn);
4702 else if (diag_kind == DK_ERROR)
4703 return error_mark_node;
4705 return build_cplus_new (totype, expr);
4709 tree ref_type = totype;
4711 /* If necessary, create a temporary.
4713 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4714 that need temporaries, even when their types are reference
4715 compatible with the type of reference being bound, so the
4716 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
4718 if (convs->need_temporary_p
4719 || TREE_CODE (expr) == CONSTRUCTOR
4720 || TREE_CODE (expr) == VA_ARG_EXPR)
4722 tree type = convs->u.next->type;
4723 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4725 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4726 && !TYPE_REF_IS_RVALUE (ref_type))
4728 if (complain & tf_error)
4730 /* If the reference is volatile or non-const, we
4731 cannot create a temporary. */
4732 if (lvalue & clk_bitfield)
4733 error ("cannot bind bitfield %qE to %qT",
4735 else if (lvalue & clk_packed)
4736 error ("cannot bind packed field %qE to %qT",
4739 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4741 return error_mark_node;
4743 /* If the source is a packed field, and we must use a copy
4744 constructor, then building the target expr will require
4745 binding the field to the reference parameter to the
4746 copy constructor, and we'll end up with an infinite
4747 loop. If we can use a bitwise copy, then we'll be
4749 if ((lvalue & clk_packed)
4750 && CLASS_TYPE_P (type)
4751 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4753 if (complain & tf_error)
4754 error ("cannot bind packed field %qE to %qT",
4756 return error_mark_node;
4758 if (lvalue & clk_bitfield)
4760 expr = convert_bitfield_to_declared_type (expr);
4761 expr = fold_convert (type, expr);
4763 expr = build_target_expr_with_type (expr, type);
4766 /* Take the address of the thing to which we will bind the
4768 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
4769 if (expr == error_mark_node)
4770 return error_mark_node;
4772 /* Convert it to a pointer to the type referred to by the
4773 reference. This will adjust the pointer if a derived to
4774 base conversion is being performed. */
4775 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4777 /* Convert the pointer to the desired reference type. */
4778 return build_nop (ref_type, expr);
4782 return decay_conversion (expr);
4785 /* Warn about deprecated conversion if appropriate. */
4786 string_conv_p (totype, expr, 1);
4791 expr = convert_to_base (expr, totype, !c_cast_p,
4793 return build_nop (totype, expr);
4796 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4803 if (convs->check_narrowing)
4804 check_narrowing (totype, expr);
4806 if (issue_conversion_warnings && (complain & tf_warning))
4807 expr = convert_and_check (totype, expr);
4809 expr = convert (totype, expr);
4814 /* Build a call to __builtin_trap. */
4817 call_builtin_trap (void)
4819 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4821 gcc_assert (fn != NULL);
4822 fn = build_call_n (fn, 0);
4826 /* ARG is being passed to a varargs function. Perform any conversions
4827 required. Return the converted value. */
4830 convert_arg_to_ellipsis (tree arg)
4834 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4835 standard conversions are performed. */
4836 arg = decay_conversion (arg);
4839 If the argument has integral or enumeration type that is subject
4840 to the integral promotions (_conv.prom_), or a floating point
4841 type that is subject to the floating point promotion
4842 (_conv.fpprom_), the value of the argument is converted to the
4843 promoted type before the call. */
4844 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4845 && (TYPE_PRECISION (TREE_TYPE (arg))
4846 < TYPE_PRECISION (double_type_node)))
4847 arg = convert_to_real (double_type_node, arg);
4848 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4849 arg = perform_integral_promotions (arg);
4851 arg = require_complete_type (arg);
4853 if (arg != error_mark_node
4854 && !pod_type_p (TREE_TYPE (arg)))
4856 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4857 here and do a bitwise copy, but now cp_expr_size will abort if we
4859 If the call appears in the context of a sizeof expression,
4860 there is no need to emit a warning, since the expression won't be
4861 evaluated. We keep the builtin_trap just as a safety check. */
4862 if (!skip_evaluation)
4863 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4864 "call will abort at runtime", TREE_TYPE (arg));
4865 arg = call_builtin_trap ();
4866 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4873 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4876 build_x_va_arg (tree expr, tree type)
4878 if (processing_template_decl)
4879 return build_min (VA_ARG_EXPR, type, expr);
4881 type = complete_type_or_else (type, NULL_TREE);
4883 if (expr == error_mark_node || !type)
4884 return error_mark_node;
4886 if (! pod_type_p (type))
4888 /* Remove reference types so we don't ICE later on. */
4889 tree type1 = non_reference (type);
4890 /* Undefined behavior [expr.call] 5.2.2/7. */
4891 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4892 "call will abort at runtime", type);
4893 expr = convert (build_pointer_type (type1), null_node);
4894 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4895 call_builtin_trap (), expr);
4896 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
4900 return build_va_arg (expr, type);
4903 /* TYPE has been given to va_arg. Apply the default conversions which
4904 would have happened when passed via ellipsis. Return the promoted
4905 type, or the passed type if there is no change. */
4908 cxx_type_promotes_to (tree type)
4912 /* Perform the array-to-pointer and function-to-pointer
4914 type = type_decays_to (type);
4916 promote = type_promotes_to (type);
4917 if (same_type_p (type, promote))
4923 /* ARG is a default argument expression being passed to a parameter of
4924 the indicated TYPE, which is a parameter to FN. Do any required
4925 conversions. Return the converted value. */
4927 static GTY(()) VEC(tree,gc) *default_arg_context;
4930 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4935 /* If the ARG is an unparsed default argument expression, the
4936 conversion cannot be performed. */
4937 if (TREE_CODE (arg) == DEFAULT_ARG)
4939 error ("the default argument for parameter %d of %qD has "
4940 "not yet been parsed",
4942 return error_mark_node;
4945 /* Detect recursion. */
4946 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
4949 error ("recursive evaluation of default argument for %q#D", fn);
4950 return error_mark_node;
4952 VEC_safe_push (tree, gc, default_arg_context, fn);
4954 if (fn && DECL_TEMPLATE_INFO (fn))
4955 arg = tsubst_default_argument (fn, type, arg);
4957 arg = break_out_target_exprs (arg);
4959 if (TREE_CODE (arg) == CONSTRUCTOR)
4961 arg = digest_init (type, arg);
4962 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4963 "default argument", fn, parmnum,
4964 tf_warning_or_error);
4968 /* We must make a copy of ARG, in case subsequent processing
4969 alters any part of it. For example, during gimplification a
4970 cast of the form (T) &X::f (where "f" is a member function)
4971 will lead to replacing the PTRMEM_CST for &X::f with a
4972 VAR_DECL. We can avoid the copy for constants, since they
4973 are never modified in place. */
4974 if (!CONSTANT_CLASS_P (arg))
4975 arg = unshare_expr (arg);
4976 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4977 "default argument", fn, parmnum,
4978 tf_warning_or_error);
4979 arg = convert_for_arg_passing (type, arg);
4982 VEC_pop (tree, default_arg_context);
4987 /* Returns the type which will really be used for passing an argument of
4991 type_passed_as (tree type)
4993 /* Pass classes with copy ctors by invisible reference. */
4994 if (TREE_ADDRESSABLE (type))
4996 type = build_reference_type (type);
4997 /* There are no other pointers to this temporary. */
4998 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5000 else if (targetm.calls.promote_prototypes (type)
5001 && INTEGRAL_TYPE_P (type)
5002 && COMPLETE_TYPE_P (type)
5003 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5004 TYPE_SIZE (integer_type_node)))
5005 type = integer_type_node;
5010 /* Actually perform the appropriate conversion. */
5013 convert_for_arg_passing (tree type, tree val)
5017 /* If VAL is a bitfield, then -- since it has already been converted
5018 to TYPE -- it cannot have a precision greater than TYPE.
5020 If it has a smaller precision, we must widen it here. For
5021 example, passing "int f:3;" to a function expecting an "int" will
5022 not result in any conversion before this point.
5024 If the precision is the same we must not risk widening. For
5025 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5026 often have type "int", even though the C++ type for the field is
5027 "long long". If the value is being passed to a function
5028 expecting an "int", then no conversions will be required. But,
5029 if we call convert_bitfield_to_declared_type, the bitfield will
5030 be converted to "long long". */
5031 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5033 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5034 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5036 if (val == error_mark_node)
5038 /* Pass classes with copy ctors by invisible reference. */
5039 else if (TREE_ADDRESSABLE (type))
5040 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5041 else if (targetm.calls.promote_prototypes (type)
5042 && INTEGRAL_TYPE_P (type)
5043 && COMPLETE_TYPE_P (type)
5044 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5045 TYPE_SIZE (integer_type_node)))
5046 val = perform_integral_promotions (val);
5047 if (warn_missing_format_attribute)
5049 tree rhstype = TREE_TYPE (val);
5050 const enum tree_code coder = TREE_CODE (rhstype);
5051 const enum tree_code codel = TREE_CODE (type);
5052 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5054 && check_missing_format_attribute (type, rhstype))
5055 warning (OPT_Wmissing_format_attribute,
5056 "argument of function call might be a candidate for a format attribute");
5061 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5062 which no conversions at all should be done. This is true for some
5063 builtins which don't act like normal functions. */
5066 magic_varargs_p (tree fn)
5068 if (DECL_BUILT_IN (fn))
5069 switch (DECL_FUNCTION_CODE (fn))
5071 case BUILT_IN_CLASSIFY_TYPE:
5072 case BUILT_IN_CONSTANT_P:
5073 case BUILT_IN_NEXT_ARG:
5074 case BUILT_IN_VA_START:
5078 return lookup_attribute ("type generic",
5079 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5085 /* Subroutine of the various build_*_call functions. Overload resolution
5086 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5087 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5088 bitmask of various LOOKUP_* flags which apply to the call itself. */
5091 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5094 tree args = cand->args;
5095 conversion **convs = cand->convs;
5097 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5105 bool already_used = false;
5107 /* In a template, there is no need to perform all of the work that
5108 is normally done. We are only interested in the type of the call
5109 expression, i.e., the return type of the function. Any semantic
5110 errors will be deferred until the template is instantiated. */
5111 if (processing_template_decl)
5115 return_type = TREE_TYPE (TREE_TYPE (fn));
5116 expr = build_call_list (return_type, build_addr_func (fn), args);
5117 if (TREE_THIS_VOLATILE (fn) && cfun)
5118 current_function_returns_abnormally = 1;
5119 if (!VOID_TYPE_P (return_type))
5120 require_complete_type (return_type);
5121 return convert_from_reference (expr);
5124 /* Give any warnings we noticed during overload resolution. */
5127 struct candidate_warning *w;
5128 for (w = cand->warnings; w; w = w->next)
5129 joust (cand, w->loser, 1);
5132 /* Make =delete work with SFINAE. */
5133 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5134 return error_mark_node;
5136 if (DECL_FUNCTION_MEMBER_P (fn))
5138 /* If FN is a template function, two cases must be considered.
5143 template <class T> void f();
5145 template <class T> struct B {
5149 struct C : A, B<int> {
5151 using B<int>::g; // #2
5154 In case #1 where `A::f' is a member template, DECL_ACCESS is
5155 recorded in the primary template but not in its specialization.
5156 We check access of FN using its primary template.
5158 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5159 because it is a member of class template B, DECL_ACCESS is
5160 recorded in the specialization `B<int>::g'. We cannot use its
5161 primary template because `B<T>::g' and `B<int>::g' may have
5162 different access. */
5163 if (DECL_TEMPLATE_INFO (fn)
5164 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5165 perform_or_defer_access_check (cand->access_path,
5166 DECL_TI_TEMPLATE (fn), fn);
5168 perform_or_defer_access_check (cand->access_path, fn, fn);
5171 if (args && TREE_CODE (args) != TREE_LIST)
5172 args = build_tree_list (NULL_TREE, args);
5175 /* Find maximum size of vector to hold converted arguments. */
5176 parmlen = list_length (parm);
5177 nargs = list_length (args);
5178 if (parmlen > nargs)
5180 argarray = (tree *) alloca (nargs * sizeof (tree));
5182 /* The implicit parameters to a constructor are not considered by overload
5183 resolution, and must be of the proper type. */
5184 if (DECL_CONSTRUCTOR_P (fn))
5186 argarray[j++] = TREE_VALUE (arg);
5187 arg = TREE_CHAIN (arg);
5188 parm = TREE_CHAIN (parm);
5189 /* We should never try to call the abstract constructor. */
5190 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5192 if (DECL_HAS_VTT_PARM_P (fn))
5194 argarray[j++] = TREE_VALUE (arg);
5195 arg = TREE_CHAIN (arg);
5196 parm = TREE_CHAIN (parm);
5199 /* Bypass access control for 'this' parameter. */
5200 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5202 tree parmtype = TREE_VALUE (parm);
5203 tree argtype = TREE_TYPE (TREE_VALUE (arg));
5207 if (convs[i]->bad_p)
5209 if (complain & tf_error)
5210 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5211 TREE_TYPE (argtype), fn);
5213 return error_mark_node;
5216 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5217 X is called for an object that is not of type X, or of a type
5218 derived from X, the behavior is undefined.
5220 So we can assume that anything passed as 'this' is non-null, and
5221 optimize accordingly. */
5222 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5223 /* Convert to the base in which the function was declared. */
5224 gcc_assert (cand->conversion_path != NULL_TREE);
5225 converted_arg = build_base_path (PLUS_EXPR,
5227 cand->conversion_path,
5229 /* Check that the base class is accessible. */
5230 if (!accessible_base_p (TREE_TYPE (argtype),
5231 BINFO_TYPE (cand->conversion_path), true))
5232 error ("%qT is not an accessible base of %qT",
5233 BINFO_TYPE (cand->conversion_path),
5234 TREE_TYPE (argtype));
5235 /* If fn was found by a using declaration, the conversion path
5236 will be to the derived class, not the base declaring fn. We
5237 must convert from derived to base. */
5238 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5239 TREE_TYPE (parmtype), ba_unique, NULL);
5240 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5243 argarray[j++] = converted_arg;
5244 parm = TREE_CHAIN (parm);
5245 arg = TREE_CHAIN (arg);
5251 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
5253 tree type = TREE_VALUE (parm);
5257 /* Don't make a copy here if build_call is going to. */
5258 if (conv->kind == ck_rvalue
5259 && COMPLETE_TYPE_P (complete_type (type))
5260 && !TREE_ADDRESSABLE (type))
5261 conv = conv->u.next;
5263 val = convert_like_with_context
5264 (conv, TREE_VALUE (arg), fn, i - is_method, complain);
5266 val = convert_for_arg_passing (type, val);
5267 if ((complain == tf_none) && val == error_mark_node)
5268 return error_mark_node;
5270 argarray[j++] = val;
5273 /* Default arguments */
5274 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5275 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5276 TREE_PURPOSE (parm),
5279 for (; arg; arg = TREE_CHAIN (arg))
5281 tree a = TREE_VALUE (arg);
5282 if (magic_varargs_p (fn))
5283 /* Do no conversions for magic varargs. */;
5285 a = convert_arg_to_ellipsis (a);
5289 gcc_assert (j <= nargs);
5292 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5293 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5295 /* Avoid actually calling copy constructors and copy assignment operators,
5298 if (! flag_elide_constructors)
5299 /* Do things the hard way. */;
5300 else if (cand->num_convs == 1
5301 && (DECL_COPY_CONSTRUCTOR_P (fn)
5302 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5305 arg = argarray[num_artificial_parms_for (fn)];
5307 /* Pull out the real argument, disregarding const-correctness. */
5309 while (CONVERT_EXPR_P (targ)
5310 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5311 targ = TREE_OPERAND (targ, 0);
5312 if (TREE_CODE (targ) == ADDR_EXPR)
5314 targ = TREE_OPERAND (targ, 0);
5315 if (!same_type_ignoring_top_level_qualifiers_p
5316 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5325 arg = cp_build_indirect_ref (arg, 0, complain);
5327 if (TREE_CODE (arg) == TARGET_EXPR
5328 && TARGET_EXPR_LIST_INIT_P (arg))
5330 /* Copy-list-initialization doesn't require the copy constructor
5333 /* [class.copy]: the copy constructor is implicitly defined even if
5334 the implementation elided its use. */
5335 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5338 already_used = true;
5341 /* If we're creating a temp and we already have one, don't create a
5342 new one. If we're not creating a temp but we get one, use
5343 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5344 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5345 temp or an INIT_EXPR otherwise. */
5346 if (integer_zerop (TREE_VALUE (args)))
5348 if (TREE_CODE (arg) == TARGET_EXPR)
5350 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5351 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5353 else if (TREE_CODE (arg) == TARGET_EXPR
5354 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5355 && !move_fn_p (fn)))
5357 tree to = stabilize_reference
5358 (cp_build_indirect_ref (TREE_VALUE (args), 0, complain));
5360 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5364 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5366 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5368 tree to = stabilize_reference
5369 (cp_build_indirect_ref (argarray[0], 0, complain));
5370 tree type = TREE_TYPE (to);
5371 tree as_base = CLASSTYPE_AS_BASE (type);
5374 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5376 arg = cp_build_indirect_ref (arg, 0, complain);
5377 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5381 /* We must only copy the non-tail padding parts.
5382 Use __builtin_memcpy for the bitwise copy. */
5384 tree arg0, arg1, arg2, t;
5386 arg2 = TYPE_SIZE_UNIT (as_base);
5388 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5389 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5390 t = build_call_n (t, 3, arg0, arg1, arg2);
5392 t = convert (TREE_TYPE (arg0), t);
5393 val = cp_build_indirect_ref (t, 0, complain);
5402 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5405 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5408 gcc_assert (binfo && binfo != error_mark_node);
5410 /* Warn about deprecated virtual functions now, since we're about
5411 to throw away the decl. */
5412 if (TREE_DEPRECATED (fn))
5413 warn_deprecated_use (fn);
5415 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5416 if (TREE_SIDE_EFFECTS (argarray[0]))
5417 argarray[0] = save_expr (argarray[0]);
5418 t = build_pointer_type (TREE_TYPE (fn));
5419 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5420 fn = build_java_interface_fn_ref (fn, argarray[0]);
5422 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5426 fn = build_addr_func (fn);
5428 return build_cxx_call (fn, nargs, argarray);
5431 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5432 This function performs no overload resolution, conversion, or other
5433 high-level operations. */
5436 build_cxx_call (tree fn, int nargs, tree *argarray)
5440 fn = build_call_a (fn, nargs, argarray);
5442 /* If this call might throw an exception, note that fact. */
5443 fndecl = get_callee_fndecl (fn);
5444 if ((!fndecl || !TREE_NOTHROW (fndecl))
5445 && at_function_scope_p ()
5447 cp_function_chain->can_throw = 1;
5449 /* Check that arguments to builtin functions match the expectations. */
5451 && DECL_BUILT_IN (fndecl)
5452 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5453 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5454 return error_mark_node;
5456 /* Some built-in function calls will be evaluated at compile-time in
5458 fn = fold_if_not_in_template (fn);
5460 if (VOID_TYPE_P (TREE_TYPE (fn)))
5463 fn = require_complete_type (fn);
5464 if (fn == error_mark_node)
5465 return error_mark_node;
5467 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5468 fn = build_cplus_new (TREE_TYPE (fn), fn);
5469 return convert_from_reference (fn);
5472 static GTY(()) tree java_iface_lookup_fn;
5474 /* Make an expression which yields the address of the Java interface
5475 method FN. This is achieved by generating a call to libjava's
5476 _Jv_LookupInterfaceMethodIdx(). */
5479 build_java_interface_fn_ref (tree fn, tree instance)
5481 tree lookup_fn, method, idx;
5482 tree klass_ref, iface, iface_ref;
5485 if (!java_iface_lookup_fn)
5487 tree endlink = build_void_list_node ();
5488 tree t = tree_cons (NULL_TREE, ptr_type_node,
5489 tree_cons (NULL_TREE, ptr_type_node,
5490 tree_cons (NULL_TREE, java_int_type_node,
5492 java_iface_lookup_fn
5493 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5494 build_function_type (ptr_type_node, t),
5495 0, NOT_BUILT_IN, NULL, NULL_TREE);
5498 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5499 This is the first entry in the vtable. */
5500 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5501 tf_warning_or_error),
5504 /* Get the java.lang.Class pointer for the interface being called. */
5505 iface = DECL_CONTEXT (fn);
5506 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5507 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5508 || DECL_CONTEXT (iface_ref) != iface)
5510 error ("could not find class$ field in java interface type %qT",
5512 return error_mark_node;
5514 iface_ref = build_address (iface_ref);
5515 iface_ref = convert (build_pointer_type (iface), iface_ref);
5517 /* Determine the itable index of FN. */
5519 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5521 if (!DECL_VIRTUAL_P (method))
5527 idx = build_int_cst (NULL_TREE, i);
5529 lookup_fn = build1 (ADDR_EXPR,
5530 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5531 java_iface_lookup_fn);
5532 return build_call_nary (ptr_type_node, lookup_fn,
5533 3, klass_ref, iface_ref, idx);
5536 /* Returns the value to use for the in-charge parameter when making a
5537 call to a function with the indicated NAME.
5539 FIXME:Can't we find a neater way to do this mapping? */
5542 in_charge_arg_for_name (tree name)
5544 if (name == base_ctor_identifier
5545 || name == base_dtor_identifier)
5546 return integer_zero_node;
5547 else if (name == complete_ctor_identifier)
5548 return integer_one_node;
5549 else if (name == complete_dtor_identifier)
5550 return integer_two_node;
5551 else if (name == deleting_dtor_identifier)
5552 return integer_three_node;
5554 /* This function should only be called with one of the names listed
5560 /* Build a call to a constructor, destructor, or an assignment
5561 operator for INSTANCE, an expression with class type. NAME
5562 indicates the special member function to call; ARGS are the
5563 arguments. BINFO indicates the base of INSTANCE that is to be
5564 passed as the `this' parameter to the member function called.
5566 FLAGS are the LOOKUP_* flags to use when processing the call.
5568 If NAME indicates a complete object constructor, INSTANCE may be
5569 NULL_TREE. In this case, the caller will call build_cplus_new to
5570 store the newly constructed object into a VAR_DECL. */
5573 build_special_member_call (tree instance, tree name, tree args,
5574 tree binfo, int flags, tsubst_flags_t complain)
5577 /* The type of the subobject to be constructed or destroyed. */
5580 gcc_assert (name == complete_ctor_identifier
5581 || name == base_ctor_identifier
5582 || name == complete_dtor_identifier
5583 || name == base_dtor_identifier
5584 || name == deleting_dtor_identifier
5585 || name == ansi_assopname (NOP_EXPR));
5588 /* Resolve the name. */
5589 if (!complete_type_or_else (binfo, NULL_TREE))
5590 return error_mark_node;
5592 binfo = TYPE_BINFO (binfo);
5595 gcc_assert (binfo != NULL_TREE);
5597 class_type = BINFO_TYPE (binfo);
5599 /* Handle the special case where INSTANCE is NULL_TREE. */
5600 if (name == complete_ctor_identifier && !instance)
5602 instance = build_int_cst (build_pointer_type (class_type), 0);
5603 instance = build1 (INDIRECT_REF, class_type, instance);
5607 if (name == complete_dtor_identifier
5608 || name == base_dtor_identifier
5609 || name == deleting_dtor_identifier)
5610 gcc_assert (args == NULL_TREE);
5612 /* Convert to the base class, if necessary. */
5613 if (!same_type_ignoring_top_level_qualifiers_p
5614 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5616 if (name != ansi_assopname (NOP_EXPR))
5617 /* For constructors and destructors, either the base is
5618 non-virtual, or it is virtual but we are doing the
5619 conversion from a constructor or destructor for the
5620 complete object. In either case, we can convert
5622 instance = convert_to_base_statically (instance, binfo);
5624 /* However, for assignment operators, we must convert
5625 dynamically if the base is virtual. */
5626 instance = build_base_path (PLUS_EXPR, instance,
5627 binfo, /*nonnull=*/1);
5631 gcc_assert (instance != NULL_TREE);
5633 fns = lookup_fnfields (binfo, name, 1);
5635 /* When making a call to a constructor or destructor for a subobject
5636 that uses virtual base classes, pass down a pointer to a VTT for
5638 if ((name == base_ctor_identifier
5639 || name == base_dtor_identifier)
5640 && CLASSTYPE_VBASECLASSES (class_type))
5645 /* If the current function is a complete object constructor
5646 or destructor, then we fetch the VTT directly.
5647 Otherwise, we look it up using the VTT we were given. */
5648 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5649 vtt = decay_conversion (vtt);
5650 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5651 build2 (EQ_EXPR, boolean_type_node,
5652 current_in_charge_parm, integer_zero_node),
5655 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5656 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5657 BINFO_SUBVTT_INDEX (binfo));
5659 args = tree_cons (NULL_TREE, sub_vtt, args);
5662 return build_new_method_call (instance, fns, args,
5663 TYPE_BINFO (BINFO_TYPE (binfo)),
5668 /* Return the NAME, as a C string. The NAME indicates a function that
5669 is a member of TYPE. *FREE_P is set to true if the caller must
5670 free the memory returned.
5672 Rather than go through all of this, we should simply set the names
5673 of constructors and destructors appropriately, and dispense with
5674 ctor_identifier, dtor_identifier, etc. */
5677 name_as_c_string (tree name, tree type, bool *free_p)
5681 /* Assume that we will not allocate memory. */
5683 /* Constructors and destructors are special. */
5684 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5687 = CONST_CAST (char *, IDENTIFIER_POINTER (constructor_name (type)));
5688 /* For a destructor, add the '~'. */
5689 if (name == complete_dtor_identifier
5690 || name == base_dtor_identifier
5691 || name == deleting_dtor_identifier)
5693 pretty_name = concat ("~", pretty_name, NULL);
5694 /* Remember that we need to free the memory allocated. */
5698 else if (IDENTIFIER_TYPENAME_P (name))
5700 pretty_name = concat ("operator ",
5701 type_as_string (TREE_TYPE (name),
5702 TFF_PLAIN_IDENTIFIER),
5704 /* Remember that we need to free the memory allocated. */
5708 pretty_name = CONST_CAST (char *, IDENTIFIER_POINTER (name));
5713 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
5714 be set, upon return, to the function called. */
5717 build_new_method_call (tree instance, tree fns, tree args,
5718 tree conversion_path, int flags,
5719 tree *fn_p, tsubst_flags_t complain)
5721 struct z_candidate *candidates = 0, *cand;
5722 tree explicit_targs = NULL_TREE;
5723 tree basetype = NULL_TREE;
5726 tree mem_args = NULL_TREE, instance_ptr;
5732 int template_only = 0;
5739 gcc_assert (instance != NULL_TREE);
5741 /* We don't know what function we're going to call, yet. */
5745 if (error_operand_p (instance)
5746 || error_operand_p (fns)
5747 || args == error_mark_node)
5748 return error_mark_node;
5750 if (!BASELINK_P (fns))
5752 if (complain & tf_error)
5753 error ("call to non-function %qD", fns);
5754 return error_mark_node;
5757 orig_instance = instance;
5761 /* Dismantle the baselink to collect all the information we need. */
5762 if (!conversion_path)
5763 conversion_path = BASELINK_BINFO (fns);
5764 access_binfo = BASELINK_ACCESS_BINFO (fns);
5765 optype = BASELINK_OPTYPE (fns);
5766 fns = BASELINK_FUNCTIONS (fns);
5767 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5769 explicit_targs = TREE_OPERAND (fns, 1);
5770 fns = TREE_OPERAND (fns, 0);
5773 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5774 || TREE_CODE (fns) == TEMPLATE_DECL
5775 || TREE_CODE (fns) == OVERLOAD);
5776 fn = get_first_fn (fns);
5777 name = DECL_NAME (fn);
5779 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5780 gcc_assert (CLASS_TYPE_P (basetype));
5782 if (processing_template_decl)
5784 instance = build_non_dependent_expr (instance);
5785 args = build_non_dependent_args (orig_args);
5788 /* The USER_ARGS are the arguments we will display to users if an
5789 error occurs. The USER_ARGS should not include any
5790 compiler-generated arguments. The "this" pointer hasn't been
5791 added yet. However, we must remove the VTT pointer if this is a
5792 call to a base-class constructor or destructor. */
5794 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5796 /* Callers should explicitly indicate whether they want to construct
5797 the complete object or just the part without virtual bases. */
5798 gcc_assert (name != ctor_identifier);
5799 /* Similarly for destructors. */
5800 gcc_assert (name != dtor_identifier);
5801 /* Remove the VTT pointer, if present. */
5802 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5803 && CLASSTYPE_VBASECLASSES (basetype))
5804 user_args = TREE_CHAIN (user_args);
5807 /* Process the argument list. */
5808 args = resolve_args (args);
5809 if (args == error_mark_node)
5810 return error_mark_node;
5812 instance_ptr = build_this (instance);
5814 /* It's OK to call destructors and constructors on cv-qualified objects.
5815 Therefore, convert the INSTANCE_PTR to the unqualified type, if
5817 if (DECL_DESTRUCTOR_P (fn)
5818 || DECL_CONSTRUCTOR_P (fn))
5820 tree type = build_pointer_type (basetype);
5821 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5822 instance_ptr = build_nop (type, instance_ptr);
5824 if (DECL_DESTRUCTOR_P (fn))
5825 name = complete_dtor_identifier;
5827 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
5828 initializer, not T({ }). If the type doesn't have a list ctor,
5829 break apart the list into separate ctor args. */
5830 if (DECL_CONSTRUCTOR_P (fn) && args
5831 && BRACE_ENCLOSED_INITIALIZER_P (TREE_VALUE (args))
5832 && CONSTRUCTOR_IS_DIRECT_INIT (TREE_VALUE (args))
5833 && !TYPE_HAS_LIST_CTOR (basetype))
5835 gcc_assert (TREE_CHAIN (args) == NULL_TREE);
5836 args = ctor_to_list (TREE_VALUE (args));
5839 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5840 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5842 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5843 p = conversion_obstack_alloc (0);
5845 for (fn = fns; fn; fn = OVL_NEXT (fn))
5847 tree t = OVL_CURRENT (fn);
5850 /* We can end up here for copy-init of same or base class. */
5851 if ((flags & LOOKUP_ONLYCONVERTING)
5852 && DECL_NONCONVERTING_P (t))
5855 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5856 this_arglist = mem_args;
5858 this_arglist = args;
5860 if (TREE_CODE (t) == TEMPLATE_DECL)
5861 /* A member template. */
5862 add_template_candidate (&candidates, t,
5865 this_arglist, optype,
5870 else if (! template_only)
5871 add_function_candidate (&candidates, t,
5879 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5882 if (complain & tf_error)
5884 if (!COMPLETE_TYPE_P (basetype))
5885 cxx_incomplete_type_error (instance_ptr, basetype);
5891 pretty_name = name_as_c_string (name, basetype, &free_p);
5892 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5893 basetype, pretty_name, user_args,
5894 TREE_TYPE (TREE_TYPE (instance_ptr)));
5898 print_z_candidates (candidates);
5900 call = error_mark_node;
5904 cand = tourney (candidates);
5910 if (complain & tf_error)
5912 pretty_name = name_as_c_string (name, basetype, &free_p);
5913 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5915 print_z_candidates (candidates);
5919 call = error_mark_node;
5925 if (!(flags & LOOKUP_NONVIRTUAL)
5926 && DECL_PURE_VIRTUAL_P (fn)
5927 && instance == current_class_ref
5928 && (DECL_CONSTRUCTOR_P (current_function_decl)
5929 || DECL_DESTRUCTOR_P (current_function_decl))
5930 && (complain & tf_warning))
5931 /* This is not an error, it is runtime undefined
5933 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5934 "abstract virtual %q#D called from constructor"
5935 : "abstract virtual %q#D called from destructor"),
5938 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
5939 && is_dummy_object (instance_ptr))
5941 if (complain & tf_error)
5942 error ("cannot call member function %qD without object",
5944 call = error_mark_node;
5948 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
5949 && resolves_to_fixed_type_p (instance, 0))
5950 flags |= LOOKUP_NONVIRTUAL;
5951 /* Now we know what function is being called. */
5954 /* Build the actual CALL_EXPR. */
5955 call = build_over_call (cand, flags, complain);
5956 /* In an expression of the form `a->f()' where `f' turns
5957 out to be a static member function, `a' is
5958 none-the-less evaluated. */
5959 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
5960 && !is_dummy_object (instance_ptr)
5961 && TREE_SIDE_EFFECTS (instance_ptr))
5962 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5963 instance_ptr, call);
5964 else if (call != error_mark_node
5965 && DECL_DESTRUCTOR_P (cand->fn)
5966 && !VOID_TYPE_P (TREE_TYPE (call)))
5967 /* An explicit call of the form "x->~X()" has type
5968 "void". However, on platforms where destructors
5969 return "this" (i.e., those where
5970 targetm.cxx.cdtor_returns_this is true), such calls
5971 will appear to have a return value of pointer type
5972 to the low-level call machinery. We do not want to
5973 change the low-level machinery, since we want to be
5974 able to optimize "delete f()" on such platforms as
5975 "operator delete(~X(f()))" (rather than generating
5976 "t = f(), ~X(t), operator delete (t)"). */
5977 call = build_nop (void_type_node, call);
5982 if (processing_template_decl && call != error_mark_node)
5984 if (TREE_CODE (call) == INDIRECT_REF)
5985 call = TREE_OPERAND (call, 0);
5986 call = (build_min_non_dep_call_list
5988 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
5989 orig_instance, orig_fns, NULL_TREE),
5991 call = convert_from_reference (call);
5994 /* Free all the conversions we allocated. */
5995 obstack_free (&conversion_obstack, p);
6000 /* Returns true iff standard conversion sequence ICS1 is a proper
6001 subsequence of ICS2. */
6004 is_subseq (conversion *ics1, conversion *ics2)
6006 /* We can assume that a conversion of the same code
6007 between the same types indicates a subsequence since we only get
6008 here if the types we are converting from are the same. */
6010 while (ics1->kind == ck_rvalue
6011 || ics1->kind == ck_lvalue)
6012 ics1 = ics1->u.next;
6016 while (ics2->kind == ck_rvalue
6017 || ics2->kind == ck_lvalue)
6018 ics2 = ics2->u.next;
6020 if (ics2->kind == ck_user
6021 || ics2->kind == ck_ambig
6022 || ics2->kind == ck_identity)
6023 /* At this point, ICS1 cannot be a proper subsequence of
6024 ICS2. We can get a USER_CONV when we are comparing the
6025 second standard conversion sequence of two user conversion
6029 ics2 = ics2->u.next;
6031 if (ics2->kind == ics1->kind
6032 && same_type_p (ics2->type, ics1->type)
6033 && same_type_p (ics2->u.next->type,
6034 ics1->u.next->type))
6039 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6040 be any _TYPE nodes. */
6043 is_properly_derived_from (tree derived, tree base)
6045 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6048 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6049 considers every class derived from itself. */
6050 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6051 && DERIVED_FROM_P (base, derived));
6054 /* We build the ICS for an implicit object parameter as a pointer
6055 conversion sequence. However, such a sequence should be compared
6056 as if it were a reference conversion sequence. If ICS is the
6057 implicit conversion sequence for an implicit object parameter,
6058 modify it accordingly. */
6061 maybe_handle_implicit_object (conversion **ics)
6065 /* [over.match.funcs]
6067 For non-static member functions, the type of the
6068 implicit object parameter is "reference to cv X"
6069 where X is the class of which the function is a
6070 member and cv is the cv-qualification on the member
6071 function declaration. */
6072 conversion *t = *ics;
6073 tree reference_type;
6075 /* The `this' parameter is a pointer to a class type. Make the
6076 implicit conversion talk about a reference to that same class
6078 reference_type = TREE_TYPE (t->type);
6079 reference_type = build_reference_type (reference_type);
6081 if (t->kind == ck_qual)
6083 if (t->kind == ck_ptr)
6085 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6086 t = direct_reference_binding (reference_type, t);
6088 t->rvaluedness_matches_p = 0;
6093 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6094 and return the initial reference binding conversion. Otherwise,
6095 leave *ICS unchanged and return NULL. */
6098 maybe_handle_ref_bind (conversion **ics)
6100 if ((*ics)->kind == ck_ref_bind)
6102 conversion *old_ics = *ics;
6103 *ics = old_ics->u.next;
6104 (*ics)->user_conv_p = old_ics->user_conv_p;
6105 (*ics)->bad_p = old_ics->bad_p;
6112 /* Compare two implicit conversion sequences according to the rules set out in
6113 [over.ics.rank]. Return values:
6115 1: ics1 is better than ics2
6116 -1: ics2 is better than ics1
6117 0: ics1 and ics2 are indistinguishable */
6120 compare_ics (conversion *ics1, conversion *ics2)
6126 tree deref_from_type1 = NULL_TREE;
6127 tree deref_from_type2 = NULL_TREE;
6128 tree deref_to_type1 = NULL_TREE;
6129 tree deref_to_type2 = NULL_TREE;
6130 conversion_rank rank1, rank2;
6132 /* REF_BINDING is nonzero if the result of the conversion sequence
6133 is a reference type. In that case REF_CONV is the reference
6134 binding conversion. */
6135 conversion *ref_conv1;
6136 conversion *ref_conv2;
6138 /* Handle implicit object parameters. */
6139 maybe_handle_implicit_object (&ics1);
6140 maybe_handle_implicit_object (&ics2);
6142 /* Handle reference parameters. */
6143 ref_conv1 = maybe_handle_ref_bind (&ics1);
6144 ref_conv2 = maybe_handle_ref_bind (&ics2);
6148 When comparing the basic forms of implicit conversion sequences (as
6149 defined in _over.best.ics_)
6151 --a standard conversion sequence (_over.ics.scs_) is a better
6152 conversion sequence than a user-defined conversion sequence
6153 or an ellipsis conversion sequence, and
6155 --a user-defined conversion sequence (_over.ics.user_) is a
6156 better conversion sequence than an ellipsis conversion sequence
6157 (_over.ics.ellipsis_). */
6158 rank1 = CONVERSION_RANK (ics1);
6159 rank2 = CONVERSION_RANK (ics2);
6163 else if (rank1 < rank2)
6166 if (rank1 == cr_bad)
6168 /* XXX Isn't this an extension? */
6169 /* Both ICS are bad. We try to make a decision based on what
6170 would have happened if they'd been good. */
6171 if (ics1->user_conv_p > ics2->user_conv_p
6172 || ics1->rank > ics2->rank)
6174 else if (ics1->user_conv_p < ics2->user_conv_p
6175 || ics1->rank < ics2->rank)
6178 /* We couldn't make up our minds; try to figure it out below. */
6181 if (ics1->ellipsis_p)
6182 /* Both conversions are ellipsis conversions. */
6185 /* User-defined conversion sequence U1 is a better conversion sequence
6186 than another user-defined conversion sequence U2 if they contain the
6187 same user-defined conversion operator or constructor and if the sec-
6188 ond standard conversion sequence of U1 is better than the second
6189 standard conversion sequence of U2. */
6191 if (ics1->user_conv_p)
6196 for (t1 = ics1; t1->kind != ck_user && t1->kind != ck_list; t1 = t1->u.next)
6197 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6199 for (t2 = ics2; t2->kind != ck_user && t2->kind != ck_list; t2 = t2->u.next)
6200 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6203 /* Conversion to std::initializer_list is better than other
6204 user-defined conversions. */
6205 if (t1->kind == ck_list
6206 || t2->kind == ck_list)
6208 if (t2->kind != ck_list)
6210 else if (t1->kind != ck_list)
6216 if (t1->cand->fn != t2->cand->fn)
6219 /* We can just fall through here, after setting up
6220 FROM_TYPE1 and FROM_TYPE2. */
6221 from_type1 = t1->type;
6222 from_type2 = t2->type;
6229 /* We're dealing with two standard conversion sequences.
6233 Standard conversion sequence S1 is a better conversion
6234 sequence than standard conversion sequence S2 if
6236 --S1 is a proper subsequence of S2 (comparing the conversion
6237 sequences in the canonical form defined by _over.ics.scs_,
6238 excluding any Lvalue Transformation; the identity
6239 conversion sequence is considered to be a subsequence of
6240 any non-identity conversion sequence */
6243 while (t1->kind != ck_identity)
6245 from_type1 = t1->type;
6248 while (t2->kind != ck_identity)
6250 from_type2 = t2->type;
6253 /* One sequence can only be a subsequence of the other if they start with
6254 the same type. They can start with different types when comparing the
6255 second standard conversion sequence in two user-defined conversion
6257 if (same_type_p (from_type1, from_type2))
6259 if (is_subseq (ics1, ics2))
6261 if (is_subseq (ics2, ics1))
6269 --the rank of S1 is better than the rank of S2 (by the rules
6272 Standard conversion sequences are ordered by their ranks: an Exact
6273 Match is a better conversion than a Promotion, which is a better
6274 conversion than a Conversion.
6276 Two conversion sequences with the same rank are indistinguishable
6277 unless one of the following rules applies:
6279 --A conversion that is not a conversion of a pointer, or pointer
6280 to member, to bool is better than another conversion that is such
6283 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6284 so that we do not have to check it explicitly. */
6285 if (ics1->rank < ics2->rank)
6287 else if (ics2->rank < ics1->rank)
6290 to_type1 = ics1->type;
6291 to_type2 = ics2->type;
6293 /* A conversion from scalar arithmetic type to complex is worse than a
6294 conversion between scalar arithmetic types. */
6295 if (same_type_p (from_type1, from_type2)
6296 && ARITHMETIC_TYPE_P (from_type1)
6297 && ARITHMETIC_TYPE_P (to_type1)
6298 && ARITHMETIC_TYPE_P (to_type2)
6299 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6300 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6302 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6308 if (TYPE_PTR_P (from_type1)
6309 && TYPE_PTR_P (from_type2)
6310 && TYPE_PTR_P (to_type1)
6311 && TYPE_PTR_P (to_type2))
6313 deref_from_type1 = TREE_TYPE (from_type1);
6314 deref_from_type2 = TREE_TYPE (from_type2);
6315 deref_to_type1 = TREE_TYPE (to_type1);
6316 deref_to_type2 = TREE_TYPE (to_type2);
6318 /* The rules for pointers to members A::* are just like the rules
6319 for pointers A*, except opposite: if B is derived from A then
6320 A::* converts to B::*, not vice versa. For that reason, we
6321 switch the from_ and to_ variables here. */
6322 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6323 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6324 || (TYPE_PTRMEMFUNC_P (from_type1)
6325 && TYPE_PTRMEMFUNC_P (from_type2)
6326 && TYPE_PTRMEMFUNC_P (to_type1)
6327 && TYPE_PTRMEMFUNC_P (to_type2)))
6329 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6330 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6331 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6332 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6335 if (deref_from_type1 != NULL_TREE
6336 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6337 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6339 /* This was one of the pointer or pointer-like conversions.
6343 --If class B is derived directly or indirectly from class A,
6344 conversion of B* to A* is better than conversion of B* to
6345 void*, and conversion of A* to void* is better than
6346 conversion of B* to void*. */
6347 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6348 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6350 if (is_properly_derived_from (deref_from_type1,
6353 else if (is_properly_derived_from (deref_from_type2,
6357 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6358 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6360 if (same_type_p (deref_from_type1, deref_from_type2))
6362 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6364 if (is_properly_derived_from (deref_from_type1,
6368 /* We know that DEREF_TO_TYPE1 is `void' here. */
6369 else if (is_properly_derived_from (deref_from_type1,
6374 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6375 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6379 --If class B is derived directly or indirectly from class A
6380 and class C is derived directly or indirectly from B,
6382 --conversion of C* to B* is better than conversion of C* to
6385 --conversion of B* to A* is better than conversion of C* to
6387 if (same_type_p (deref_from_type1, deref_from_type2))
6389 if (is_properly_derived_from (deref_to_type1,
6392 else if (is_properly_derived_from (deref_to_type2,
6396 else if (same_type_p (deref_to_type1, deref_to_type2))
6398 if (is_properly_derived_from (deref_from_type2,
6401 else if (is_properly_derived_from (deref_from_type1,
6407 else if (CLASS_TYPE_P (non_reference (from_type1))
6408 && same_type_p (from_type1, from_type2))
6410 tree from = non_reference (from_type1);
6414 --binding of an expression of type C to a reference of type
6415 B& is better than binding an expression of type C to a
6416 reference of type A&
6418 --conversion of C to B is better than conversion of C to A, */
6419 if (is_properly_derived_from (from, to_type1)
6420 && is_properly_derived_from (from, to_type2))
6422 if (is_properly_derived_from (to_type1, to_type2))
6424 else if (is_properly_derived_from (to_type2, to_type1))
6428 else if (CLASS_TYPE_P (non_reference (to_type1))
6429 && same_type_p (to_type1, to_type2))
6431 tree to = non_reference (to_type1);
6435 --binding of an expression of type B to a reference of type
6436 A& is better than binding an expression of type C to a
6437 reference of type A&,
6439 --conversion of B to A is better than conversion of C to A */
6440 if (is_properly_derived_from (from_type1, to)
6441 && is_properly_derived_from (from_type2, to))
6443 if (is_properly_derived_from (from_type2, from_type1))
6445 else if (is_properly_derived_from (from_type1, from_type2))
6452 --S1 and S2 differ only in their qualification conversion and yield
6453 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6454 qualification signature of type T1 is a proper subset of the cv-
6455 qualification signature of type T2 */
6456 if (ics1->kind == ck_qual
6457 && ics2->kind == ck_qual
6458 && same_type_p (from_type1, from_type2))
6460 int result = comp_cv_qual_signature (to_type1, to_type2);
6467 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6468 to an implicit object parameter, and either S1 binds an lvalue reference
6469 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6470 reference to an rvalue and S2 binds an lvalue reference
6471 (C++0x draft standard, 13.3.3.2)
6473 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6474 types to which the references refer are the same type except for
6475 top-level cv-qualifiers, and the type to which the reference
6476 initialized by S2 refers is more cv-qualified than the type to
6477 which the reference initialized by S1 refers */
6479 if (ref_conv1 && ref_conv2)
6481 if (!ref_conv1->this_p && !ref_conv2->this_p
6482 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6483 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6485 if (ref_conv1->rvaluedness_matches_p)
6487 if (ref_conv2->rvaluedness_matches_p)
6491 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6492 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6493 TREE_TYPE (ref_conv1->type));
6496 /* Neither conversion sequence is better than the other. */
6500 /* The source type for this standard conversion sequence. */
6503 source_type (conversion *t)
6505 for (;; t = t->u.next)
6507 if (t->kind == ck_user
6508 || t->kind == ck_ambig
6509 || t->kind == ck_identity)
6515 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6516 a pointer to LOSER and re-running joust to produce the warning if WINNER
6517 is actually used. */
6520 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6522 candidate_warning *cw = (candidate_warning *)
6523 conversion_obstack_alloc (sizeof (candidate_warning));
6525 cw->next = winner->warnings;
6526 winner->warnings = cw;
6529 /* Compare two candidates for overloading as described in
6530 [over.match.best]. Return values:
6532 1: cand1 is better than cand2
6533 -1: cand2 is better than cand1
6534 0: cand1 and cand2 are indistinguishable */
6537 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6540 int off1 = 0, off2 = 0;
6544 /* Candidates that involve bad conversions are always worse than those
6546 if (cand1->viable > cand2->viable)
6548 if (cand1->viable < cand2->viable)
6551 /* If we have two pseudo-candidates for conversions to the same type,
6552 or two candidates for the same function, arbitrarily pick one. */
6553 if (cand1->fn == cand2->fn
6554 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6557 /* a viable function F1
6558 is defined to be a better function than another viable function F2 if
6559 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6560 ICSi(F2), and then */
6562 /* for some argument j, ICSj(F1) is a better conversion sequence than
6565 /* For comparing static and non-static member functions, we ignore
6566 the implicit object parameter of the non-static function. The
6567 standard says to pretend that the static function has an object
6568 parm, but that won't work with operator overloading. */
6569 len = cand1->num_convs;
6570 if (len != cand2->num_convs)
6572 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6573 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6575 gcc_assert (static_1 != static_2);
6586 for (i = 0; i < len; ++i)
6588 conversion *t1 = cand1->convs[i + off1];
6589 conversion *t2 = cand2->convs[i + off2];
6590 int comp = compare_ics (t1, t2);
6595 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6596 == cr_std + cr_promotion)
6597 && t1->kind == ck_std
6598 && t2->kind == ck_std
6599 && TREE_CODE (t1->type) == INTEGER_TYPE
6600 && TREE_CODE (t2->type) == INTEGER_TYPE
6601 && (TYPE_PRECISION (t1->type)
6602 == TYPE_PRECISION (t2->type))
6603 && (TYPE_UNSIGNED (t1->u.next->type)
6604 || (TREE_CODE (t1->u.next->type)
6607 tree type = t1->u.next->type;
6609 struct z_candidate *w, *l;
6611 type1 = t1->type, type2 = t2->type,
6612 w = cand1, l = cand2;
6614 type1 = t2->type, type2 = t1->type,
6615 w = cand2, l = cand1;
6619 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6620 type, type1, type2);
6621 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6627 if (winner && comp != winner)
6636 /* warn about confusing overload resolution for user-defined conversions,
6637 either between a constructor and a conversion op, or between two
6639 if (winner && warn_conversion && cand1->second_conv
6640 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6641 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6643 struct z_candidate *w, *l;
6644 bool give_warning = false;
6647 w = cand1, l = cand2;
6649 w = cand2, l = cand1;
6651 /* We don't want to complain about `X::operator T1 ()'
6652 beating `X::operator T2 () const', when T2 is a no less
6653 cv-qualified version of T1. */
6654 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6655 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6657 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6658 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6660 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6665 if (!comp_ptr_ttypes (t, f))
6666 give_warning = true;
6669 give_warning = true;
6675 tree source = source_type (w->convs[0]);
6676 if (! DECL_CONSTRUCTOR_P (w->fn))
6677 source = TREE_TYPE (source);
6678 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
6679 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
6680 source, w->second_conv->type))
6682 inform (input_location, " because conversion sequence for the argument is better");
6693 F1 is a non-template function and F2 is a template function
6696 if (!cand1->template_decl && cand2->template_decl)
6698 else if (cand1->template_decl && !cand2->template_decl)
6702 F1 and F2 are template functions and the function template for F1 is
6703 more specialized than the template for F2 according to the partial
6706 if (cand1->template_decl && cand2->template_decl)
6708 winner = more_specialized_fn
6709 (TI_TEMPLATE (cand1->template_decl),
6710 TI_TEMPLATE (cand2->template_decl),
6711 /* [temp.func.order]: The presence of unused ellipsis and default
6712 arguments has no effect on the partial ordering of function
6713 templates. add_function_candidate() will not have
6714 counted the "this" argument for constructors. */
6715 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6721 the context is an initialization by user-defined conversion (see
6722 _dcl.init_ and _over.match.user_) and the standard conversion
6723 sequence from the return type of F1 to the destination type (i.e.,
6724 the type of the entity being initialized) is a better conversion
6725 sequence than the standard conversion sequence from the return type
6726 of F2 to the destination type. */
6728 if (cand1->second_conv)
6730 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6735 /* Check whether we can discard a builtin candidate, either because we
6736 have two identical ones or matching builtin and non-builtin candidates.
6738 (Pedantically in the latter case the builtin which matched the user
6739 function should not be added to the overload set, but we spot it here.
6742 ... the builtin candidates include ...
6743 - do not have the same parameter type list as any non-template
6744 non-member candidate. */
6746 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6747 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6749 for (i = 0; i < len; ++i)
6750 if (!same_type_p (cand1->convs[i]->type,
6751 cand2->convs[i]->type))
6753 if (i == cand1->num_convs)
6755 if (cand1->fn == cand2->fn)
6756 /* Two built-in candidates; arbitrarily pick one. */
6758 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6759 /* cand1 is built-in; prefer cand2. */
6762 /* cand2 is built-in; prefer cand1. */
6767 /* If the two functions are the same (this can happen with declarations
6768 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6769 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6770 && equal_functions (cand1->fn, cand2->fn))
6775 /* Extension: If the worst conversion for one candidate is worse than the
6776 worst conversion for the other, take the first. */
6779 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6780 struct z_candidate *w = 0, *l = 0;
6782 for (i = 0; i < len; ++i)
6784 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6785 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6786 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6787 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6790 winner = 1, w = cand1, l = cand2;
6792 winner = -1, w = cand2, l = cand1;
6797 pedwarn (input_location, 0,
6798 "ISO C++ says that these are ambiguous, even "
6799 "though the worst conversion for the first is better than "
6800 "the worst conversion for the second:");
6801 print_z_candidate (_("candidate 1:"), w);
6802 print_z_candidate (_("candidate 2:"), l);
6810 gcc_assert (!winner);
6814 /* Given a list of candidates for overloading, find the best one, if any.
6815 This algorithm has a worst case of O(2n) (winner is last), and a best
6816 case of O(n/2) (totally ambiguous); much better than a sorting
6819 static struct z_candidate *
6820 tourney (struct z_candidate *candidates)
6822 struct z_candidate *champ = candidates, *challenger;
6824 int champ_compared_to_predecessor = 0;
6826 /* Walk through the list once, comparing each current champ to the next
6827 candidate, knocking out a candidate or two with each comparison. */
6829 for (challenger = champ->next; challenger; )
6831 fate = joust (champ, challenger, 0);
6833 challenger = challenger->next;
6838 champ = challenger->next;
6841 champ_compared_to_predecessor = 0;
6846 champ_compared_to_predecessor = 1;
6849 challenger = champ->next;
6853 /* Make sure the champ is better than all the candidates it hasn't yet
6854 been compared to. */
6856 for (challenger = candidates;
6858 && !(champ_compared_to_predecessor && challenger->next == champ);
6859 challenger = challenger->next)
6861 fate = joust (champ, challenger, 0);
6869 /* Returns nonzero if things of type FROM can be converted to TO. */
6872 can_convert (tree to, tree from)
6874 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6877 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6880 can_convert_arg (tree to, tree from, tree arg, int flags)
6886 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6887 p = conversion_obstack_alloc (0);
6889 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6891 ok_p = (t && !t->bad_p);
6893 /* Free all the conversions we allocated. */
6894 obstack_free (&conversion_obstack, p);
6899 /* Like can_convert_arg, but allows dubious conversions as well. */
6902 can_convert_arg_bad (tree to, tree from, tree arg)
6907 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6908 p = conversion_obstack_alloc (0);
6909 /* Try to perform the conversion. */
6910 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6912 /* Free all the conversions we allocated. */
6913 obstack_free (&conversion_obstack, p);
6918 /* Convert EXPR to TYPE. Return the converted expression.
6920 Note that we allow bad conversions here because by the time we get to
6921 this point we are committed to doing the conversion. If we end up
6922 doing a bad conversion, convert_like will complain. */
6925 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
6930 if (error_operand_p (expr))
6931 return error_mark_node;
6933 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6934 p = conversion_obstack_alloc (0);
6936 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6941 if (complain & tf_error)
6942 error ("could not convert %qE to %qT", expr, type);
6943 expr = error_mark_node;
6945 else if (processing_template_decl)
6947 /* In a template, we are only concerned about determining the
6948 type of non-dependent expressions, so we do not have to
6949 perform the actual conversion. */
6950 if (TREE_TYPE (expr) != type)
6951 expr = build_nop (type, expr);
6954 expr = convert_like (conv, expr, complain);
6956 /* Free all the conversions we allocated. */
6957 obstack_free (&conversion_obstack, p);
6962 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6963 permitted. If the conversion is valid, the converted expression is
6964 returned. Otherwise, NULL_TREE is returned, except in the case
6965 that TYPE is a class type; in that case, an error is issued. If
6966 C_CAST_P is true, then this direction initialization is taking
6967 place as part of a static_cast being attempted as part of a C-style
6971 perform_direct_initialization_if_possible (tree type,
6974 tsubst_flags_t complain)
6979 if (type == error_mark_node || error_operand_p (expr))
6980 return error_mark_node;
6983 If the destination type is a (possibly cv-qualified) class type:
6985 -- If the initialization is direct-initialization ...,
6986 constructors are considered. ... If no constructor applies, or
6987 the overload resolution is ambiguous, the initialization is
6989 if (CLASS_TYPE_P (type))
6991 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6992 build_tree_list (NULL_TREE, expr),
6993 type, LOOKUP_NORMAL, complain);
6994 return build_cplus_new (type, expr);
6997 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6998 p = conversion_obstack_alloc (0);
7000 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7003 if (!conv || conv->bad_p)
7006 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7007 /*issue_conversion_warnings=*/false,
7009 tf_warning_or_error);
7011 /* Free all the conversions we allocated. */
7012 obstack_free (&conversion_obstack, p);
7017 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7018 is being bound to a temporary. Create and return a new VAR_DECL
7019 with the indicated TYPE; this variable will store the value to
7020 which the reference is bound. */
7023 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7027 /* Create the variable. */
7028 var = create_temporary_var (type);
7030 /* Register the variable. */
7031 if (TREE_STATIC (decl))
7033 /* Namespace-scope or local static; give it a mangled name. */
7036 TREE_STATIC (var) = 1;
7037 name = mangle_ref_init_variable (decl);
7038 DECL_NAME (var) = name;
7039 SET_DECL_ASSEMBLER_NAME (var, name);
7040 var = pushdecl_top_level (var);
7043 /* Create a new cleanup level if necessary. */
7044 maybe_push_cleanup_level (type);
7049 /* EXPR is the initializer for a variable DECL of reference or
7050 std::initializer_list type. Create, push and return a new VAR_DECL
7051 for the initializer so that it will live as long as DECL. Any
7052 cleanup for the new variable is returned through CLEANUP, and the
7053 code to initialize the new variable is returned through INITP. */
7056 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7062 /* Create the temporary variable. */
7063 type = TREE_TYPE (expr);
7064 var = make_temporary_var_for_ref_to_temp (decl, type);
7065 layout_decl (var, 0);
7066 /* If the rvalue is the result of a function call it will be
7067 a TARGET_EXPR. If it is some other construct (such as a
7068 member access expression where the underlying object is
7069 itself the result of a function call), turn it into a
7070 TARGET_EXPR here. It is important that EXPR be a
7071 TARGET_EXPR below since otherwise the INIT_EXPR will
7072 attempt to make a bitwise copy of EXPR to initialize
7074 if (TREE_CODE (expr) != TARGET_EXPR)
7075 expr = get_target_expr (expr);
7076 /* Create the INIT_EXPR that will initialize the temporary
7078 init = build2 (INIT_EXPR, type, var, expr);
7079 if (at_function_scope_p ())
7081 add_decl_expr (var);
7083 if (TREE_STATIC (var))
7084 init = add_stmt_to_compound (init, register_dtor_fn (var));
7086 *cleanup = cxx_maybe_build_cleanup (var);
7088 /* We must be careful to destroy the temporary only
7089 after its initialization has taken place. If the
7090 initialization throws an exception, then the
7091 destructor should not be run. We cannot simply
7092 transform INIT into something like:
7094 (INIT, ({ CLEANUP_STMT; }))
7096 because emit_local_var always treats the
7097 initializer as a full-expression. Thus, the
7098 destructor would run too early; it would run at the
7099 end of initializing the reference variable, rather
7100 than at the end of the block enclosing the
7103 The solution is to pass back a cleanup expression
7104 which the caller is responsible for attaching to
7105 the statement tree. */
7109 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7110 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7111 static_aggregates = tree_cons (NULL_TREE, var,
7119 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7120 initializing a variable of that TYPE. If DECL is non-NULL, it is
7121 the VAR_DECL being initialized with the EXPR. (In that case, the
7122 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7123 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7124 return, if *CLEANUP is no longer NULL, it will be an expression
7125 that should be pushed as a cleanup after the returned expression
7126 is used to initialize DECL.
7128 Return the converted expression. */
7131 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7136 if (type == error_mark_node || error_operand_p (expr))
7137 return error_mark_node;
7139 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7140 p = conversion_obstack_alloc (0);
7142 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7144 if (!conv || conv->bad_p)
7146 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7147 && !real_lvalue_p (expr))
7148 error ("invalid initialization of non-const reference of "
7149 "type %qT from a temporary of type %qT",
7150 type, TREE_TYPE (expr));
7152 error ("invalid initialization of reference of type "
7153 "%qT from expression of type %qT", type,
7155 return error_mark_node;
7158 /* If DECL is non-NULL, then this special rule applies:
7162 The temporary to which the reference is bound or the temporary
7163 that is the complete object to which the reference is bound
7164 persists for the lifetime of the reference.
7166 The temporaries created during the evaluation of the expression
7167 initializing the reference, except the temporary to which the
7168 reference is bound, are destroyed at the end of the
7169 full-expression in which they are created.
7171 In that case, we store the converted expression into a new
7172 VAR_DECL in a new scope.
7174 However, we want to be careful not to create temporaries when
7175 they are not required. For example, given:
7178 struct D : public B {};
7182 there is no need to copy the return value from "f"; we can just
7183 extend its lifetime. Similarly, given:
7186 struct T { operator S(); };
7190 we can extend the lifetime of the return value of the conversion
7192 gcc_assert (conv->kind == ck_ref_bind);
7196 tree base_conv_type;
7198 /* Skip over the REF_BIND. */
7199 conv = conv->u.next;
7200 /* If the next conversion is a BASE_CONV, skip that too -- but
7201 remember that the conversion was required. */
7202 if (conv->kind == ck_base)
7204 base_conv_type = conv->type;
7205 conv = conv->u.next;
7208 base_conv_type = NULL_TREE;
7209 /* Perform the remainder of the conversion. */
7210 expr = convert_like_real (conv, expr,
7211 /*fn=*/NULL_TREE, /*argnum=*/0,
7213 /*issue_conversion_warnings=*/true,
7215 tf_warning_or_error);
7216 if (error_operand_p (expr))
7217 expr = error_mark_node;
7220 if (!real_lvalue_p (expr))
7223 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7224 /* Use its address to initialize the reference variable. */
7225 expr = build_address (var);
7227 expr = convert_to_base (expr,
7228 build_pointer_type (base_conv_type),
7229 /*check_access=*/true,
7231 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7234 /* Take the address of EXPR. */
7235 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7236 /* If a BASE_CONV was required, perform it now. */
7238 expr = (perform_implicit_conversion
7239 (build_pointer_type (base_conv_type), expr,
7240 tf_warning_or_error));
7241 expr = build_nop (type, expr);
7245 /* Perform the conversion. */
7246 expr = convert_like (conv, expr, tf_warning_or_error);
7248 /* Free all the conversions we allocated. */
7249 obstack_free (&conversion_obstack, p);
7254 /* Returns true iff TYPE is some variant of std::initializer_list. */
7257 is_std_init_list (tree type)
7259 return (CLASS_TYPE_P (type)
7260 && CP_TYPE_CONTEXT (type) == std_node
7261 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7264 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7265 will accept an argument list of a single std::initializer_list<T>. */
7268 is_list_ctor (tree decl)
7270 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7273 if (!args || args == void_list_node)
7276 arg = non_reference (TREE_VALUE (args));
7277 if (!is_std_init_list (arg))
7280 args = TREE_CHAIN (args);
7282 if (args && args != void_list_node && !TREE_PURPOSE (args))
7283 /* There are more non-defaulted parms. */
7289 #include "gt-cp-call.h"