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))
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 (tcode == ENUMERAL_TYPE && 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 (MAYBE_CLASS_TYPE_P (TREE_TYPE (from))
818 && MAYBE_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, enumeration, pointer, or pointer to
900 member type can be converted to an rvalue of type bool. */
901 if (ARITHMETIC_TYPE_P (from)
902 || fcode == ENUMERAL_TYPE
903 || fcode == POINTER_TYPE
904 || TYPE_PTR_TO_MEMBER_P (from))
906 conv = build_conv (ck_std, to, conv);
907 if (fcode == POINTER_TYPE
908 || TYPE_PTRMEM_P (from)
909 || (TYPE_PTRMEMFUNC_P (from)
910 && conv->rank < cr_pbool))
911 conv->rank = cr_pbool;
917 /* We don't check for ENUMERAL_TYPE here because there are no standard
918 conversions to enum type. */
919 /* As an extension, allow conversion to complex type. */
920 else if (ARITHMETIC_TYPE_P (to))
922 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
924 conv = build_conv (ck_std, to, conv);
926 /* Give this a better rank if it's a promotion. */
927 if (same_type_p (to, type_promotes_to (from))
928 && conv->u.next->rank <= cr_promotion)
929 conv->rank = cr_promotion;
931 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
932 && vector_types_convertible_p (from, to, false))
933 return build_conv (ck_std, to, conv);
934 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
935 && is_properly_derived_from (from, to))
937 if (conv->kind == ck_rvalue)
939 conv = build_conv (ck_base, to, conv);
940 /* The derived-to-base conversion indicates the initialization
941 of a parameter with base type from an object of a derived
942 type. A temporary object is created to hold the result of
943 the conversion unless we're binding directly to a reference. */
944 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
949 if (flags & LOOKUP_NO_NARROWING)
950 conv->check_narrowing = true;
955 /* Returns nonzero if T1 is reference-related to T2. */
958 reference_related_p (tree t1, tree t2)
960 t1 = TYPE_MAIN_VARIANT (t1);
961 t2 = TYPE_MAIN_VARIANT (t2);
965 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
966 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
968 return (same_type_p (t1, t2)
969 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
970 && DERIVED_FROM_P (t1, t2)));
973 /* Returns nonzero if T1 is reference-compatible with T2. */
976 reference_compatible_p (tree t1, tree t2)
980 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
981 reference-related to T2 and cv1 is the same cv-qualification as,
982 or greater cv-qualification than, cv2. */
983 return (reference_related_p (t1, t2)
984 && at_least_as_qualified_p (t1, t2));
987 /* Determine whether or not the EXPR (of class type S) can be
988 converted to T as in [over.match.ref]. */
991 convert_class_to_reference (tree reference_type, tree s, tree expr)
997 struct z_candidate *candidates;
998 struct z_candidate *cand;
1001 conversions = lookup_conversions (s);
1007 Assuming that "cv1 T" is the underlying type of the reference
1008 being initialized, and "cv S" is the type of the initializer
1009 expression, with S a class type, the candidate functions are
1010 selected as follows:
1012 --The conversion functions of S and its base classes are
1013 considered. Those that are not hidden within S and yield type
1014 "reference to cv2 T2", where "cv1 T" is reference-compatible
1015 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1017 The argument list has one argument, which is the initializer
1022 /* Conceptually, we should take the address of EXPR and put it in
1023 the argument list. Unfortunately, however, that can result in
1024 error messages, which we should not issue now because we are just
1025 trying to find a conversion operator. Therefore, we use NULL,
1026 cast to the appropriate type. */
1027 arglist = build_int_cst (build_pointer_type (s), 0);
1028 arglist = build_tree_list (NULL_TREE, arglist);
1030 t = TREE_TYPE (reference_type);
1034 tree fns = TREE_VALUE (conversions);
1036 for (; fns; fns = OVL_NEXT (fns))
1038 tree f = OVL_CURRENT (fns);
1039 tree t2 = TREE_TYPE (TREE_TYPE (f));
1043 /* If this is a template function, try to get an exact
1045 if (TREE_CODE (f) == TEMPLATE_DECL)
1047 cand = add_template_candidate (&candidates,
1053 TREE_PURPOSE (conversions),
1059 /* Now, see if the conversion function really returns
1060 an lvalue of the appropriate type. From the
1061 point of view of unification, simply returning an
1062 rvalue of the right type is good enough. */
1064 t2 = TREE_TYPE (TREE_TYPE (f));
1065 if (TREE_CODE (t2) != REFERENCE_TYPE
1066 || !reference_compatible_p (t, TREE_TYPE (t2)))
1068 candidates = candidates->next;
1073 else if (TREE_CODE (t2) == REFERENCE_TYPE
1074 && reference_compatible_p (t, TREE_TYPE (t2)))
1075 cand = add_function_candidate (&candidates, f, s, arglist,
1077 TREE_PURPOSE (conversions),
1082 conversion *identity_conv;
1083 /* Build a standard conversion sequence indicating the
1084 binding from the reference type returned by the
1085 function to the desired REFERENCE_TYPE. */
1087 = build_identity_conv (TREE_TYPE (TREE_TYPE
1088 (TREE_TYPE (cand->fn))),
1091 = (direct_reference_binding
1092 (reference_type, identity_conv));
1093 cand->second_conv->rvaluedness_matches_p
1094 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1095 == TYPE_REF_IS_RVALUE (reference_type);
1096 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1099 conversions = TREE_CHAIN (conversions);
1102 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1103 /* If none of the conversion functions worked out, let our caller
1108 cand = tourney (candidates);
1112 /* Now that we know that this is the function we're going to use fix
1113 the dummy first argument. */
1114 cand->args = tree_cons (NULL_TREE,
1116 TREE_CHAIN (cand->args));
1118 /* Build a user-defined conversion sequence representing the
1120 conv = build_conv (ck_user,
1121 TREE_TYPE (TREE_TYPE (cand->fn)),
1122 build_identity_conv (TREE_TYPE (expr), expr));
1125 /* Merge it with the standard conversion sequence from the
1126 conversion function's return type to the desired type. */
1127 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1129 if (cand->viable == -1)
1132 return cand->second_conv;
1135 /* A reference of the indicated TYPE is being bound directly to the
1136 expression represented by the implicit conversion sequence CONV.
1137 Return a conversion sequence for this binding. */
1140 direct_reference_binding (tree type, conversion *conv)
1144 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1145 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1147 t = TREE_TYPE (type);
1151 When a parameter of reference type binds directly
1152 (_dcl.init.ref_) to an argument expression, the implicit
1153 conversion sequence is the identity conversion, unless the
1154 argument expression has a type that is a derived class of the
1155 parameter type, in which case the implicit conversion sequence is
1156 a derived-to-base Conversion.
1158 If the parameter binds directly to the result of applying a
1159 conversion function to the argument expression, the implicit
1160 conversion sequence is a user-defined conversion sequence
1161 (_over.ics.user_), with the second standard conversion sequence
1162 either an identity conversion or, if the conversion function
1163 returns an entity of a type that is a derived class of the
1164 parameter type, a derived-to-base conversion. */
1165 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1167 /* Represent the derived-to-base conversion. */
1168 conv = build_conv (ck_base, t, conv);
1169 /* We will actually be binding to the base-class subobject in
1170 the derived class, so we mark this conversion appropriately.
1171 That way, convert_like knows not to generate a temporary. */
1172 conv->need_temporary_p = false;
1174 return build_conv (ck_ref_bind, type, conv);
1177 /* Returns the conversion path from type FROM to reference type TO for
1178 purposes of reference binding. For lvalue binding, either pass a
1179 reference type to FROM or an lvalue expression to EXPR. If the
1180 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1181 the conversion returned. If C_CAST_P is true, this
1182 conversion is coming from a C-style cast. */
1185 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1187 conversion *conv = NULL;
1188 tree to = TREE_TYPE (rto);
1193 cp_lvalue_kind lvalue_p = clk_none;
1195 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1197 expr = instantiate_type (to, expr, tf_none);
1198 if (expr == error_mark_node)
1200 from = TREE_TYPE (expr);
1203 if (TREE_CODE (from) == REFERENCE_TYPE)
1205 /* Anything with reference type is an lvalue. */
1206 lvalue_p = clk_ordinary;
1207 from = TREE_TYPE (from);
1210 lvalue_p = real_lvalue_p (expr);
1213 if ((lvalue_p & clk_bitfield) != 0)
1214 tfrom = unlowered_expr_type (expr);
1216 /* Figure out whether or not the types are reference-related and
1217 reference compatible. We have do do this after stripping
1218 references from FROM. */
1219 related_p = reference_related_p (to, tfrom);
1220 /* If this is a C cast, first convert to an appropriately qualified
1221 type, so that we can later do a const_cast to the desired type. */
1222 if (related_p && c_cast_p
1223 && !at_least_as_qualified_p (to, tfrom))
1224 to = build_qualified_type (to, cp_type_quals (tfrom));
1225 compatible_p = reference_compatible_p (to, tfrom);
1227 /* Directly bind reference when target expression's type is compatible with
1228 the reference and expression is an lvalue. In DR391, the wording in
1229 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1230 const and rvalue references to rvalues of compatible class type. */
1233 || (!(flags & LOOKUP_NO_TEMP_BIND)
1234 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1235 && CLASS_TYPE_P (from))))
1239 If the initializer expression
1241 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1242 is reference-compatible with "cv2 T2,"
1244 the reference is bound directly to the initializer expression
1248 If the initializer expression is an rvalue, with T2 a class type,
1249 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1250 is bound to the object represented by the rvalue or to a sub-object
1251 within that object. */
1253 conv = build_identity_conv (tfrom, expr);
1254 conv = direct_reference_binding (rto, conv);
1256 if (flags & LOOKUP_PREFER_RVALUE)
1257 /* The top-level caller requested that we pretend that the lvalue
1258 be treated as an rvalue. */
1259 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1261 conv->rvaluedness_matches_p
1262 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1264 if ((lvalue_p & clk_bitfield) != 0
1265 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1266 /* For the purposes of overload resolution, we ignore the fact
1267 this expression is a bitfield or packed field. (In particular,
1268 [over.ics.ref] says specifically that a function with a
1269 non-const reference parameter is viable even if the
1270 argument is a bitfield.)
1272 However, when we actually call the function we must create
1273 a temporary to which to bind the reference. If the
1274 reference is volatile, or isn't const, then we cannot make
1275 a temporary, so we just issue an error when the conversion
1277 conv->need_temporary_p = true;
1281 /* [class.conv.fct] A conversion function is never used to convert a
1282 (possibly cv-qualified) object to the (possibly cv-qualified) same
1283 object type (or a reference to it), to a (possibly cv-qualified) base
1284 class of that type (or a reference to it).... */
1285 else if (CLASS_TYPE_P (from) && !related_p
1286 && !(flags & LOOKUP_NO_CONVERSION))
1290 If the initializer expression
1292 -- has a class type (i.e., T2 is a class type) can be
1293 implicitly converted to an lvalue of type "cv3 T3," where
1294 "cv1 T1" is reference-compatible with "cv3 T3". (this
1295 conversion is selected by enumerating the applicable
1296 conversion functions (_over.match.ref_) and choosing the
1297 best one through overload resolution. (_over.match_).
1299 the reference is bound to the lvalue result of the conversion
1300 in the second case. */
1301 conv = convert_class_to_reference (rto, from, expr);
1306 /* From this point on, we conceptually need temporaries, even if we
1307 elide them. Only the cases above are "direct bindings". */
1308 if (flags & LOOKUP_NO_TEMP_BIND)
1313 When a parameter of reference type is not bound directly to an
1314 argument expression, the conversion sequence is the one required
1315 to convert the argument expression to the underlying type of the
1316 reference according to _over.best.ics_. Conceptually, this
1317 conversion sequence corresponds to copy-initializing a temporary
1318 of the underlying type with the argument expression. Any
1319 difference in top-level cv-qualification is subsumed by the
1320 initialization itself and does not constitute a conversion. */
1324 Otherwise, the reference shall be to a non-volatile const type.
1326 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1327 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1332 Otherwise, a temporary of type "cv1 T1" is created and
1333 initialized from the initializer expression using the rules for a
1334 non-reference copy initialization. If T1 is reference-related to
1335 T2, cv1 must be the same cv-qualification as, or greater
1336 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1337 if (related_p && !at_least_as_qualified_p (to, from))
1340 /* We're generating a temporary now, but don't bind any more in the
1341 conversion (specifically, don't slice the temporary returned by a
1342 conversion operator). */
1343 flags |= LOOKUP_NO_TEMP_BIND;
1345 conv = implicit_conversion (to, from, expr, c_cast_p,
1350 conv = build_conv (ck_ref_bind, rto, conv);
1351 /* This reference binding, unlike those above, requires the
1352 creation of a temporary. */
1353 conv->need_temporary_p = true;
1354 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1359 /* Returns the implicit conversion sequence (see [over.ics]) from type
1360 FROM to type TO. The optional expression EXPR may affect the
1361 conversion. FLAGS are the usual overloading flags. Only
1362 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1363 conversion is coming from a C-style cast. */
1366 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1371 if (from == error_mark_node || to == error_mark_node
1372 || expr == error_mark_node)
1375 if (TREE_CODE (to) == REFERENCE_TYPE)
1376 conv = reference_binding (to, from, expr, c_cast_p, flags);
1378 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1383 if (is_std_init_list (to) && expr
1384 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1385 return build_list_conv (to, expr, flags);
1387 if (expr != NULL_TREE
1388 && (MAYBE_CLASS_TYPE_P (from)
1389 || MAYBE_CLASS_TYPE_P (to))
1390 && (flags & LOOKUP_NO_CONVERSION) == 0)
1392 struct z_candidate *cand;
1393 int convflags = ((flags & LOOKUP_NO_TEMP_BIND)
1394 |LOOKUP_ONLYCONVERTING);
1396 if (CLASS_TYPE_P (to)
1397 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1398 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1399 return build_aggr_conv (to, expr, flags);
1401 cand = build_user_type_conversion_1 (to, expr, convflags);
1403 conv = cand->second_conv;
1405 /* We used to try to bind a reference to a temporary here, but that
1406 is now handled after the recursive call to this function at the end
1407 of reference_binding. */
1414 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1417 static struct z_candidate *
1418 add_candidate (struct z_candidate **candidates,
1420 size_t num_convs, conversion **convs,
1421 tree access_path, tree conversion_path,
1424 struct z_candidate *cand = (struct z_candidate *)
1425 conversion_obstack_alloc (sizeof (struct z_candidate));
1429 cand->convs = convs;
1430 cand->num_convs = num_convs;
1431 cand->access_path = access_path;
1432 cand->conversion_path = conversion_path;
1433 cand->viable = viable;
1434 cand->next = *candidates;
1440 /* Create an overload candidate for the function or method FN called with
1441 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1442 to implicit_conversion.
1444 CTYPE, if non-NULL, is the type we want to pretend this function
1445 comes from for purposes of overload resolution. */
1447 static struct z_candidate *
1448 add_function_candidate (struct z_candidate **candidates,
1449 tree fn, tree ctype, tree arglist,
1450 tree access_path, tree conversion_path,
1453 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1456 tree parmnode, argnode;
1460 /* At this point we should not see any functions which haven't been
1461 explicitly declared, except for friend functions which will have
1462 been found using argument dependent lookup. */
1463 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1465 /* The `this', `in_chrg' and VTT arguments to constructors are not
1466 considered in overload resolution. */
1467 if (DECL_CONSTRUCTOR_P (fn))
1469 parmlist = skip_artificial_parms_for (fn, parmlist);
1470 orig_arglist = arglist;
1471 arglist = skip_artificial_parms_for (fn, arglist);
1474 orig_arglist = arglist;
1476 len = list_length (arglist);
1477 convs = alloc_conversions (len);
1479 /* 13.3.2 - Viable functions [over.match.viable]
1480 First, to be a viable function, a candidate function shall have enough
1481 parameters to agree in number with the arguments in the list.
1483 We need to check this first; otherwise, checking the ICSes might cause
1484 us to produce an ill-formed template instantiation. */
1486 parmnode = parmlist;
1487 for (i = 0; i < len; ++i)
1489 if (parmnode == NULL_TREE || parmnode == void_list_node)
1491 parmnode = TREE_CHAIN (parmnode);
1494 if (i < len && parmnode)
1497 /* Make sure there are default args for the rest of the parms. */
1498 else if (!sufficient_parms_p (parmnode))
1504 /* Second, for F to be a viable function, there shall exist for each
1505 argument an implicit conversion sequence that converts that argument
1506 to the corresponding parameter of F. */
1508 parmnode = parmlist;
1511 for (i = 0; i < len; ++i)
1513 tree arg = TREE_VALUE (argnode);
1514 tree argtype = lvalue_type (arg);
1518 if (parmnode == void_list_node)
1521 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1522 && ! DECL_CONSTRUCTOR_P (fn));
1526 tree parmtype = TREE_VALUE (parmnode);
1529 /* The type of the implicit object parameter ('this') for
1530 overload resolution is not always the same as for the
1531 function itself; conversion functions are considered to
1532 be members of the class being converted, and functions
1533 introduced by a using-declaration are considered to be
1534 members of the class that uses them.
1536 Since build_over_call ignores the ICS for the `this'
1537 parameter, we can just change the parm type. */
1538 if (ctype && is_this)
1541 = build_qualified_type (ctype,
1542 TYPE_QUALS (TREE_TYPE (parmtype)));
1543 parmtype = build_pointer_type (parmtype);
1546 if ((flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1547 && ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1548 lflags |= LOOKUP_NO_CONVERSION;
1550 t = implicit_conversion (parmtype, argtype, arg,
1551 /*c_cast_p=*/false, lflags);
1555 t = build_identity_conv (argtype, arg);
1556 t->ellipsis_p = true;
1573 parmnode = TREE_CHAIN (parmnode);
1574 argnode = TREE_CHAIN (argnode);
1578 return add_candidate (candidates, fn, orig_arglist, len, convs,
1579 access_path, conversion_path, viable);
1582 /* Create an overload candidate for the conversion function FN which will
1583 be invoked for expression OBJ, producing a pointer-to-function which
1584 will in turn be called with the argument list ARGLIST, and add it to
1585 CANDIDATES. FLAGS is passed on to implicit_conversion.
1587 Actually, we don't really care about FN; we care about the type it
1588 converts to. There may be multiple conversion functions that will
1589 convert to that type, and we rely on build_user_type_conversion_1 to
1590 choose the best one; so when we create our candidate, we record the type
1591 instead of the function. */
1593 static struct z_candidate *
1594 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1595 tree arglist, tree access_path, tree conversion_path)
1597 tree totype = TREE_TYPE (TREE_TYPE (fn));
1598 int i, len, viable, flags;
1599 tree parmlist, parmnode, argnode;
1602 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1603 parmlist = TREE_TYPE (parmlist);
1604 parmlist = TYPE_ARG_TYPES (parmlist);
1606 len = list_length (arglist) + 1;
1607 convs = alloc_conversions (len);
1608 parmnode = parmlist;
1611 flags = LOOKUP_NORMAL;
1613 /* Don't bother looking up the same type twice. */
1614 if (*candidates && (*candidates)->fn == totype)
1617 for (i = 0; i < len; ++i)
1619 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1620 tree argtype = lvalue_type (arg);
1624 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1626 else if (parmnode == void_list_node)
1629 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1630 /*c_cast_p=*/false, flags);
1633 t = build_identity_conv (argtype, arg);
1634 t->ellipsis_p = true;
1648 parmnode = TREE_CHAIN (parmnode);
1649 argnode = TREE_CHAIN (argnode);
1655 if (!sufficient_parms_p (parmnode))
1658 return add_candidate (candidates, totype, arglist, len, convs,
1659 access_path, conversion_path, viable);
1663 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1664 tree type1, tree type2, tree *args, tree *argtypes,
1676 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1677 convs = alloc_conversions (num_convs);
1679 for (i = 0; i < 2; ++i)
1684 t = implicit_conversion (types[i], argtypes[i], args[i],
1685 /*c_cast_p=*/false, flags);
1689 /* We need something for printing the candidate. */
1690 t = build_identity_conv (types[i], NULL_TREE);
1697 /* For COND_EXPR we rearranged the arguments; undo that now. */
1700 convs[2] = convs[1];
1701 convs[1] = convs[0];
1702 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1703 /*c_cast_p=*/false, flags);
1710 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1712 /*access_path=*/NULL_TREE,
1713 /*conversion_path=*/NULL_TREE,
1718 is_complete (tree t)
1720 return COMPLETE_TYPE_P (complete_type (t));
1723 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1726 promoted_arithmetic_type_p (tree type)
1730 In this section, the term promoted integral type is used to refer
1731 to those integral types which are preserved by integral promotion
1732 (including e.g. int and long but excluding e.g. char).
1733 Similarly, the term promoted arithmetic type refers to promoted
1734 integral types plus floating types. */
1735 return ((INTEGRAL_TYPE_P (type)
1736 && same_type_p (type_promotes_to (type), type))
1737 || TREE_CODE (type) == REAL_TYPE);
1740 /* Create any builtin operator overload candidates for the operator in
1741 question given the converted operand types TYPE1 and TYPE2. The other
1742 args are passed through from add_builtin_candidates to
1743 build_builtin_candidate.
1745 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1746 If CODE is requires candidates operands of the same type of the kind
1747 of which TYPE1 and TYPE2 are, we add both candidates
1748 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1751 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1752 enum tree_code code2, tree fnname, tree type1,
1753 tree type2, tree *args, tree *argtypes, int flags)
1757 case POSTINCREMENT_EXPR:
1758 case POSTDECREMENT_EXPR:
1759 args[1] = integer_zero_node;
1760 type2 = integer_type_node;
1769 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1770 and VQ is either volatile or empty, there exist candidate operator
1771 functions of the form
1772 VQ T& operator++(VQ T&);
1773 T operator++(VQ T&, int);
1774 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1775 type other than bool, and VQ is either volatile or empty, there exist
1776 candidate operator functions of the form
1777 VQ T& operator--(VQ T&);
1778 T operator--(VQ T&, int);
1779 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1780 complete object type, and VQ is either volatile or empty, there exist
1781 candidate operator functions of the form
1782 T*VQ& operator++(T*VQ&);
1783 T*VQ& operator--(T*VQ&);
1784 T* operator++(T*VQ&, int);
1785 T* operator--(T*VQ&, int); */
1787 case POSTDECREMENT_EXPR:
1788 case PREDECREMENT_EXPR:
1789 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1791 case POSTINCREMENT_EXPR:
1792 case PREINCREMENT_EXPR:
1793 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1795 type1 = build_reference_type (type1);
1800 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1801 exist candidate operator functions of the form
1805 8 For every function type T, there exist candidate operator functions of
1807 T& operator*(T*); */
1810 if (TREE_CODE (type1) == POINTER_TYPE
1811 && (TYPE_PTROB_P (type1)
1812 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1816 /* 9 For every type T, there exist candidate operator functions of the form
1819 10For every promoted arithmetic type T, there exist candidate operator
1820 functions of the form
1824 case UNARY_PLUS_EXPR: /* unary + */
1825 if (TREE_CODE (type1) == POINTER_TYPE)
1828 if (ARITHMETIC_TYPE_P (type1))
1832 /* 11For every promoted integral type T, there exist candidate operator
1833 functions of the form
1837 if (INTEGRAL_TYPE_P (type1))
1841 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1842 is the same type as C2 or is a derived class of C2, T is a complete
1843 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1844 there exist candidate operator functions of the form
1845 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1846 where CV12 is the union of CV1 and CV2. */
1849 if (TREE_CODE (type1) == POINTER_TYPE
1850 && TYPE_PTR_TO_MEMBER_P (type2))
1852 tree c1 = TREE_TYPE (type1);
1853 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1855 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1856 && (TYPE_PTRMEMFUNC_P (type2)
1857 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1862 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1863 didate operator functions of the form
1868 bool operator<(L, R);
1869 bool operator>(L, R);
1870 bool operator<=(L, R);
1871 bool operator>=(L, R);
1872 bool operator==(L, R);
1873 bool operator!=(L, R);
1874 where LR is the result of the usual arithmetic conversions between
1877 14For every pair of types T and I, where T is a cv-qualified or cv-
1878 unqualified complete object type and I is a promoted integral type,
1879 there exist candidate operator functions of the form
1880 T* operator+(T*, I);
1881 T& operator[](T*, I);
1882 T* operator-(T*, I);
1883 T* operator+(I, T*);
1884 T& operator[](I, T*);
1886 15For every T, where T is a pointer to complete object type, there exist
1887 candidate operator functions of the form112)
1888 ptrdiff_t operator-(T, T);
1890 16For every pointer or enumeration type T, there exist candidate operator
1891 functions of the form
1892 bool operator<(T, T);
1893 bool operator>(T, T);
1894 bool operator<=(T, T);
1895 bool operator>=(T, T);
1896 bool operator==(T, T);
1897 bool operator!=(T, T);
1899 17For every pointer to member type T, there exist candidate operator
1900 functions of the form
1901 bool operator==(T, T);
1902 bool operator!=(T, T); */
1905 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1907 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1909 type2 = ptrdiff_type_node;
1913 case TRUNC_DIV_EXPR:
1914 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1920 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1921 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1923 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1928 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1940 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1942 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1944 if (TREE_CODE (type1) == ENUMERAL_TYPE
1945 && TREE_CODE (type2) == ENUMERAL_TYPE)
1947 if (TYPE_PTR_P (type1)
1948 && null_ptr_cst_p (args[1])
1949 && !uses_template_parms (type1))
1954 if (null_ptr_cst_p (args[0])
1955 && TYPE_PTR_P (type2)
1956 && !uses_template_parms (type2))
1964 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1967 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1969 type1 = ptrdiff_type_node;
1972 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1974 type2 = ptrdiff_type_node;
1979 /* 18For every pair of promoted integral types L and R, there exist candi-
1980 date operator functions of the form
1987 where LR is the result of the usual arithmetic conversions between
1990 case TRUNC_MOD_EXPR:
1996 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2000 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2001 type, VQ is either volatile or empty, and R is a promoted arithmetic
2002 type, there exist candidate operator functions of the form
2003 VQ L& operator=(VQ L&, R);
2004 VQ L& operator*=(VQ L&, R);
2005 VQ L& operator/=(VQ L&, R);
2006 VQ L& operator+=(VQ L&, R);
2007 VQ L& operator-=(VQ L&, R);
2009 20For every pair T, VQ), where T is any type and VQ is either volatile
2010 or empty, there exist candidate operator functions of the form
2011 T*VQ& operator=(T*VQ&, T*);
2013 21For every pair T, VQ), where T is a pointer to member type and VQ is
2014 either volatile or empty, there exist candidate operator functions of
2016 VQ T& operator=(VQ T&, T);
2018 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2019 unqualified complete object type, VQ is either volatile or empty, and
2020 I is a promoted integral type, there exist candidate operator func-
2022 T*VQ& operator+=(T*VQ&, I);
2023 T*VQ& operator-=(T*VQ&, I);
2025 23For every triple L, VQ, R), where L is an integral or enumeration
2026 type, VQ is either volatile or empty, and R is a promoted integral
2027 type, there exist candidate operator functions of the form
2029 VQ L& operator%=(VQ L&, R);
2030 VQ L& operator<<=(VQ L&, R);
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); */
2041 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
2043 type2 = ptrdiff_type_node;
2047 case TRUNC_DIV_EXPR:
2048 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2052 case TRUNC_MOD_EXPR:
2058 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2063 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2065 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2066 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2067 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2068 || ((TYPE_PTRMEMFUNC_P (type1)
2069 || TREE_CODE (type1) == POINTER_TYPE)
2070 && null_ptr_cst_p (args[1])))
2080 type1 = build_reference_type (type1);
2086 For every pair of promoted arithmetic types L and R, there
2087 exist candidate operator functions of the form
2089 LR operator?(bool, L, R);
2091 where LR is the result of the usual arithmetic conversions
2092 between types L and R.
2094 For every type T, where T is a pointer or pointer-to-member
2095 type, there exist candidate operator functions of the form T
2096 operator?(bool, T, T); */
2098 if (promoted_arithmetic_type_p (type1)
2099 && promoted_arithmetic_type_p (type2))
2103 /* Otherwise, the types should be pointers. */
2104 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2105 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2108 /* We don't check that the two types are the same; the logic
2109 below will actually create two candidates; one in which both
2110 parameter types are TYPE1, and one in which both parameter
2118 /* If we're dealing with two pointer types or two enumeral types,
2119 we need candidates for both of them. */
2120 if (type2 && !same_type_p (type1, type2)
2121 && TREE_CODE (type1) == TREE_CODE (type2)
2122 && (TREE_CODE (type1) == REFERENCE_TYPE
2123 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2124 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2125 || TYPE_PTRMEMFUNC_P (type1)
2126 || MAYBE_CLASS_TYPE_P (type1)
2127 || TREE_CODE (type1) == ENUMERAL_TYPE))
2129 build_builtin_candidate
2130 (candidates, fnname, type1, type1, args, argtypes, flags);
2131 build_builtin_candidate
2132 (candidates, fnname, type2, type2, args, argtypes, flags);
2136 build_builtin_candidate
2137 (candidates, fnname, type1, type2, args, argtypes, flags);
2141 type_decays_to (tree type)
2143 if (TREE_CODE (type) == ARRAY_TYPE)
2144 return build_pointer_type (TREE_TYPE (type));
2145 if (TREE_CODE (type) == FUNCTION_TYPE)
2146 return build_pointer_type (type);
2150 /* There are three conditions of builtin candidates:
2152 1) bool-taking candidates. These are the same regardless of the input.
2153 2) pointer-pair taking candidates. These are generated for each type
2154 one of the input types converts to.
2155 3) arithmetic candidates. According to the standard, we should generate
2156 all of these, but I'm trying not to...
2158 Here we generate a superset of the possible candidates for this particular
2159 case. That is a subset of the full set the standard defines, plus some
2160 other cases which the standard disallows. add_builtin_candidate will
2161 filter out the invalid set. */
2164 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2165 enum tree_code code2, tree fnname, tree *args,
2170 tree type, argtypes[3];
2171 /* TYPES[i] is the set of possible builtin-operator parameter types
2172 we will consider for the Ith argument. These are represented as
2173 a TREE_LIST; the TREE_VALUE of each node is the potential
2177 for (i = 0; i < 3; ++i)
2180 argtypes[i] = unlowered_expr_type (args[i]);
2182 argtypes[i] = NULL_TREE;
2187 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2188 and VQ is either volatile or empty, there exist candidate operator
2189 functions of the form
2190 VQ T& operator++(VQ T&); */
2192 case POSTINCREMENT_EXPR:
2193 case PREINCREMENT_EXPR:
2194 case POSTDECREMENT_EXPR:
2195 case PREDECREMENT_EXPR:
2200 /* 24There also exist candidate operator functions of the form
2201 bool operator!(bool);
2202 bool operator&&(bool, bool);
2203 bool operator||(bool, bool); */
2205 case TRUTH_NOT_EXPR:
2206 build_builtin_candidate
2207 (candidates, fnname, boolean_type_node,
2208 NULL_TREE, args, argtypes, flags);
2211 case TRUTH_ORIF_EXPR:
2212 case TRUTH_ANDIF_EXPR:
2213 build_builtin_candidate
2214 (candidates, fnname, boolean_type_node,
2215 boolean_type_node, args, argtypes, flags);
2237 types[0] = types[1] = NULL_TREE;
2239 for (i = 0; i < 2; ++i)
2243 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2247 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2250 convs = lookup_conversions (argtypes[i]);
2252 if (code == COND_EXPR)
2254 if (real_lvalue_p (args[i]))
2255 types[i] = tree_cons
2256 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2258 types[i] = tree_cons
2259 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2265 for (; convs; convs = TREE_CHAIN (convs))
2267 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2270 && (TREE_CODE (type) != REFERENCE_TYPE
2271 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2274 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2275 types[i] = tree_cons (NULL_TREE, type, types[i]);
2277 type = non_reference (type);
2278 if (i != 0 || ! ref1)
2280 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2281 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2282 types[i] = tree_cons (NULL_TREE, type, types[i]);
2283 if (INTEGRAL_TYPE_P (type))
2284 type = type_promotes_to (type);
2287 if (! value_member (type, types[i]))
2288 types[i] = tree_cons (NULL_TREE, type, types[i]);
2293 if (code == COND_EXPR && real_lvalue_p (args[i]))
2294 types[i] = tree_cons
2295 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2296 type = non_reference (argtypes[i]);
2297 if (i != 0 || ! ref1)
2299 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2300 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2301 types[i] = tree_cons (NULL_TREE, type, types[i]);
2302 if (INTEGRAL_TYPE_P (type))
2303 type = type_promotes_to (type);
2305 types[i] = tree_cons (NULL_TREE, type, types[i]);
2309 /* Run through the possible parameter types of both arguments,
2310 creating candidates with those parameter types. */
2311 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2314 for (type = types[1]; type; type = TREE_CHAIN (type))
2315 add_builtin_candidate
2316 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2317 TREE_VALUE (type), args, argtypes, flags);
2319 add_builtin_candidate
2320 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2321 NULL_TREE, args, argtypes, flags);
2326 /* If TMPL can be successfully instantiated as indicated by
2327 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2329 TMPL is the template. EXPLICIT_TARGS are any explicit template
2330 arguments. ARGLIST is the arguments provided at the call-site.
2331 The RETURN_TYPE is the desired type for conversion operators. If
2332 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2333 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2334 add_conv_candidate. */
2336 static struct z_candidate*
2337 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2338 tree ctype, tree explicit_targs, tree arglist,
2339 tree return_type, tree access_path,
2340 tree conversion_path, int flags, tree obj,
2341 unification_kind_t strict)
2343 int ntparms = DECL_NTPARMS (tmpl);
2344 tree targs = make_tree_vec (ntparms);
2345 tree args_without_in_chrg = arglist;
2346 struct z_candidate *cand;
2350 /* We don't do deduction on the in-charge parameter, the VTT
2351 parameter or 'this'. */
2352 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2353 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2355 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2356 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2357 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2358 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2360 i = fn_type_unification (tmpl, explicit_targs, targs,
2361 args_without_in_chrg,
2362 return_type, strict, flags);
2367 fn = instantiate_template (tmpl, targs, tf_none);
2368 if (fn == error_mark_node)
2373 A member function template is never instantiated to perform the
2374 copy of a class object to an object of its class type.
2376 It's a little unclear what this means; the standard explicitly
2377 does allow a template to be used to copy a class. For example,
2382 template <class T> A(const T&);
2385 void g () { A a (f ()); }
2387 the member template will be used to make the copy. The section
2388 quoted above appears in the paragraph that forbids constructors
2389 whose only parameter is (a possibly cv-qualified variant of) the
2390 class type, and a logical interpretation is that the intent was
2391 to forbid the instantiation of member templates which would then
2393 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2395 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2396 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2401 if (obj != NULL_TREE)
2402 /* Aha, this is a conversion function. */
2403 cand = add_conv_candidate (candidates, fn, obj, access_path,
2404 conversion_path, arglist);
2406 cand = add_function_candidate (candidates, fn, ctype,
2407 arglist, access_path,
2408 conversion_path, flags);
2409 if (DECL_TI_TEMPLATE (fn) != tmpl)
2410 /* This situation can occur if a member template of a template
2411 class is specialized. Then, instantiate_template might return
2412 an instantiation of the specialization, in which case the
2413 DECL_TI_TEMPLATE field will point at the original
2414 specialization. For example:
2416 template <class T> struct S { template <class U> void f(U);
2417 template <> void f(int) {}; };
2421 Here, TMPL will be template <class U> S<double>::f(U).
2422 And, instantiate template will give us the specialization
2423 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2424 for this will point at template <class T> template <> S<T>::f(int),
2425 so that we can find the definition. For the purposes of
2426 overload resolution, however, we want the original TMPL. */
2427 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2429 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2435 static struct z_candidate *
2436 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2437 tree explicit_targs, tree arglist, tree return_type,
2438 tree access_path, tree conversion_path, int flags,
2439 unification_kind_t strict)
2442 add_template_candidate_real (candidates, tmpl, ctype,
2443 explicit_targs, arglist, return_type,
2444 access_path, conversion_path,
2445 flags, NULL_TREE, strict);
2449 static struct z_candidate *
2450 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2451 tree obj, tree arglist, tree return_type,
2452 tree access_path, tree conversion_path)
2455 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2456 arglist, return_type, access_path,
2457 conversion_path, 0, obj, DEDUCE_CONV);
2460 /* The CANDS are the set of candidates that were considered for
2461 overload resolution. Return the set of viable candidates. If none
2462 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2463 is true if a candidate should be considered viable only if it is
2466 static struct z_candidate*
2467 splice_viable (struct z_candidate *cands,
2471 struct z_candidate *viable;
2472 struct z_candidate **last_viable;
2473 struct z_candidate **cand;
2476 last_viable = &viable;
2477 *any_viable_p = false;
2482 struct z_candidate *c = *cand;
2483 if (strict_p ? c->viable == 1 : c->viable)
2488 last_viable = &c->next;
2489 *any_viable_p = true;
2495 return viable ? viable : cands;
2499 any_strictly_viable (struct z_candidate *cands)
2501 for (; cands; cands = cands->next)
2502 if (cands->viable == 1)
2507 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2508 words, it is about to become the "this" pointer for a member
2509 function call. Take the address of the object. */
2512 build_this (tree obj)
2514 /* In a template, we are only concerned about the type of the
2515 expression, so we can take a shortcut. */
2516 if (processing_template_decl)
2517 return build_address (obj);
2519 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2522 /* Returns true iff functions are equivalent. Equivalent functions are
2523 not '==' only if one is a function-local extern function or if
2524 both are extern "C". */
2527 equal_functions (tree fn1, tree fn2)
2529 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2530 || DECL_EXTERN_C_FUNCTION_P (fn1))
2531 return decls_match (fn1, fn2);
2535 /* Print information about one overload candidate CANDIDATE. MSGSTR
2536 is the text to print before the candidate itself.
2538 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2539 to have been run through gettext by the caller. This wart makes
2540 life simpler in print_z_candidates and for the translators. */
2543 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2545 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2547 if (candidate->num_convs == 3)
2548 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2549 candidate->convs[0]->type,
2550 candidate->convs[1]->type,
2551 candidate->convs[2]->type);
2552 else if (candidate->num_convs == 2)
2553 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2554 candidate->convs[0]->type,
2555 candidate->convs[1]->type);
2557 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2558 candidate->convs[0]->type);
2560 else if (TYPE_P (candidate->fn))
2561 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2562 else if (candidate->viable == -1)
2563 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2565 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2569 print_z_candidates (struct z_candidate *candidates)
2572 struct z_candidate *cand1;
2573 struct z_candidate **cand2;
2575 /* There may be duplicates in the set of candidates. We put off
2576 checking this condition as long as possible, since we have no way
2577 to eliminate duplicates from a set of functions in less than n^2
2578 time. Now we are about to emit an error message, so it is more
2579 permissible to go slowly. */
2580 for (cand1 = candidates; cand1; cand1 = cand1->next)
2582 tree fn = cand1->fn;
2583 /* Skip builtin candidates and conversion functions. */
2584 if (TREE_CODE (fn) != FUNCTION_DECL)
2586 cand2 = &cand1->next;
2589 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2590 && equal_functions (fn, (*cand2)->fn))
2591 *cand2 = (*cand2)->next;
2593 cand2 = &(*cand2)->next;
2600 str = _("candidates are:");
2601 print_z_candidate (str, candidates);
2602 if (candidates->next)
2604 /* Indent successive candidates by the width of the translation
2605 of the above string. */
2606 size_t len = gcc_gettext_width (str) + 1;
2607 char *spaces = (char *) alloca (len);
2608 memset (spaces, ' ', len-1);
2609 spaces[len - 1] = '\0';
2611 candidates = candidates->next;
2614 print_z_candidate (spaces, candidates);
2615 candidates = candidates->next;
2621 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2622 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2623 the result of the conversion function to convert it to the final
2624 desired type. Merge the two sequences into a single sequence,
2625 and return the merged sequence. */
2628 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2632 gcc_assert (user_seq->kind == ck_user);
2634 /* Find the end of the second conversion sequence. */
2636 while ((*t)->kind != ck_identity)
2637 t = &((*t)->u.next);
2639 /* Replace the identity conversion with the user conversion
2643 /* The entire sequence is a user-conversion sequence. */
2644 std_seq->user_conv_p = true;
2649 /* Returns the best overload candidate to perform the requested
2650 conversion. This function is used for three the overloading situations
2651 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2652 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2653 per [dcl.init.ref], so we ignore temporary bindings. */
2655 static struct z_candidate *
2656 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2658 struct z_candidate *candidates, *cand;
2659 tree fromtype = TREE_TYPE (expr);
2660 tree ctors = NULL_TREE;
2661 tree conv_fns = NULL_TREE;
2662 conversion *conv = NULL;
2663 tree args = NULL_TREE;
2667 /* We represent conversion within a hierarchy using RVALUE_CONV and
2668 BASE_CONV, as specified by [over.best.ics]; these become plain
2669 constructor calls, as specified in [dcl.init]. */
2670 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2671 || !DERIVED_FROM_P (totype, fromtype));
2673 if (MAYBE_CLASS_TYPE_P (totype))
2674 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2676 if (MAYBE_CLASS_TYPE_P (fromtype))
2678 tree to_nonref = non_reference (totype);
2679 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2680 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2681 && DERIVED_FROM_P (to_nonref, fromtype)))
2683 /* [class.conv.fct] A conversion function is never used to
2684 convert a (possibly cv-qualified) object to the (possibly
2685 cv-qualified) same object type (or a reference to it), to a
2686 (possibly cv-qualified) base class of that type (or a
2687 reference to it)... */
2690 conv_fns = lookup_conversions (fromtype);
2694 flags |= LOOKUP_NO_CONVERSION;
2696 /* It's OK to bind a temporary for converting constructor arguments, but
2697 not in converting the return value of a conversion operator. */
2698 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2699 flags &= ~LOOKUP_NO_TEMP_BIND;
2705 ctors = BASELINK_FUNCTIONS (ctors);
2707 t = build_int_cst (build_pointer_type (totype), 0);
2708 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2709 && !TYPE_HAS_LIST_CTOR (totype))
2711 args = ctor_to_list (expr);
2712 /* We still allow more conversions within an init-list. */
2713 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2714 /* But not for the copy ctor. */
2715 |LOOKUP_NO_COPY_CTOR_CONVERSION
2716 |LOOKUP_NO_NARROWING);
2719 args = build_tree_list (NULL_TREE, expr);
2720 /* We should never try to call the abstract or base constructor
2722 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2723 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2724 args = tree_cons (NULL_TREE, t, args);
2726 for (; ctors; ctors = OVL_NEXT (ctors))
2728 tree ctor = OVL_CURRENT (ctors);
2729 if (DECL_NONCONVERTING_P (ctor)
2730 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2733 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2734 cand = add_template_candidate (&candidates, ctor, totype,
2735 NULL_TREE, args, NULL_TREE,
2736 TYPE_BINFO (totype),
2737 TYPE_BINFO (totype),
2741 cand = add_function_candidate (&candidates, ctor, totype,
2742 args, TYPE_BINFO (totype),
2743 TYPE_BINFO (totype),
2748 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2750 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2751 set, then this is copy-initialization. In that case, "The
2752 result of the call is then used to direct-initialize the
2753 object that is the destination of the copy-initialization."
2756 We represent this in the conversion sequence with an
2757 rvalue conversion, which means a constructor call. */
2758 if (TREE_CODE (totype) != REFERENCE_TYPE
2759 && !(convflags & LOOKUP_NO_TEMP_BIND))
2761 = build_conv (ck_rvalue, totype, cand->second_conv);
2766 args = build_tree_list (NULL_TREE, build_this (expr));
2768 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2771 tree conversion_path = TREE_PURPOSE (conv_fns);
2773 /* If we are called to convert to a reference type, we are trying to
2774 find an lvalue binding, so don't even consider temporaries. If
2775 we don't find an lvalue binding, the caller will try again to
2776 look for a temporary binding. */
2777 if (TREE_CODE (totype) == REFERENCE_TYPE)
2778 convflags |= LOOKUP_NO_TEMP_BIND;
2780 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2782 tree fn = OVL_CURRENT (fns);
2784 /* [over.match.funcs] For conversion functions, the function
2785 is considered to be a member of the class of the implicit
2786 object argument for the purpose of defining the type of
2787 the implicit object parameter.
2789 So we pass fromtype as CTYPE to add_*_candidate. */
2791 if (TREE_CODE (fn) == TEMPLATE_DECL)
2792 cand = add_template_candidate (&candidates, fn, fromtype,
2795 TYPE_BINFO (fromtype),
2800 cand = add_function_candidate (&candidates, fn, fromtype,
2802 TYPE_BINFO (fromtype),
2809 = implicit_conversion (totype,
2810 TREE_TYPE (TREE_TYPE (cand->fn)),
2812 /*c_cast_p=*/false, convflags);
2814 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2815 copy-initialization. In that case, "The result of the
2816 call is then used to direct-initialize the object that is
2817 the destination of the copy-initialization." [dcl.init]
2819 We represent this in the conversion sequence with an
2820 rvalue conversion, which means a constructor call. But
2821 don't add a second rvalue conversion if there's already
2822 one there. Which there really shouldn't be, but it's
2823 harmless since we'd add it here anyway. */
2824 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2825 && !(convflags & LOOKUP_NO_TEMP_BIND))
2826 ics = build_conv (ck_rvalue, totype, ics);
2828 cand->second_conv = ics;
2832 else if (candidates->viable == 1 && ics->bad_p)
2838 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2842 cand = tourney (candidates);
2845 if (flags & LOOKUP_COMPLAIN)
2847 error ("conversion from %qT to %qT is ambiguous",
2849 print_z_candidates (candidates);
2852 cand = candidates; /* any one will do */
2853 cand->second_conv = build_ambiguous_conv (totype, expr);
2854 cand->second_conv->user_conv_p = true;
2855 if (!any_strictly_viable (candidates))
2856 cand->second_conv->bad_p = true;
2857 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2858 ambiguous conversion is no worse than another user-defined
2864 /* Build the user conversion sequence. */
2867 (DECL_CONSTRUCTOR_P (cand->fn)
2868 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2869 build_identity_conv (TREE_TYPE (expr), expr));
2872 /* Combine it with the second conversion sequence. */
2873 cand->second_conv = merge_conversion_sequences (conv,
2876 if (cand->viable == -1)
2877 cand->second_conv->bad_p = true;
2883 build_user_type_conversion (tree totype, tree expr, int flags)
2885 struct z_candidate *cand
2886 = build_user_type_conversion_1 (totype, expr, flags);
2890 if (cand->second_conv->kind == ck_ambig)
2891 return error_mark_node;
2892 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
2893 return convert_from_reference (expr);
2898 /* Do any initial processing on the arguments to a function call. */
2901 resolve_args (tree args)
2904 for (t = args; t; t = TREE_CHAIN (t))
2906 tree arg = TREE_VALUE (t);
2908 if (error_operand_p (arg))
2909 return error_mark_node;
2910 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2912 error ("invalid use of void expression");
2913 return error_mark_node;
2915 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
2916 return error_mark_node;
2921 /* Perform overload resolution on FN, which is called with the ARGS.
2923 Return the candidate function selected by overload resolution, or
2924 NULL if the event that overload resolution failed. In the case
2925 that overload resolution fails, *CANDIDATES will be the set of
2926 candidates considered, and ANY_VIABLE_P will be set to true or
2927 false to indicate whether or not any of the candidates were
2930 The ARGS should already have gone through RESOLVE_ARGS before this
2931 function is called. */
2933 static struct z_candidate *
2934 perform_overload_resolution (tree fn,
2936 struct z_candidate **candidates,
2939 struct z_candidate *cand;
2940 tree explicit_targs = NULL_TREE;
2941 int template_only = 0;
2944 *any_viable_p = true;
2946 /* Check FN and ARGS. */
2947 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2948 || TREE_CODE (fn) == TEMPLATE_DECL
2949 || TREE_CODE (fn) == OVERLOAD
2950 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2951 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2953 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2955 explicit_targs = TREE_OPERAND (fn, 1);
2956 fn = TREE_OPERAND (fn, 0);
2960 /* Add the various candidate functions. */
2961 add_candidates (fn, args, explicit_targs, template_only,
2962 /*conversion_path=*/NULL_TREE,
2963 /*access_path=*/NULL_TREE,
2967 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2971 cand = tourney (*candidates);
2975 /* Return an expression for a call to FN (a namespace-scope function,
2976 or a static member function) with the ARGS. */
2979 build_new_function_call (tree fn, tree args, bool koenig_p,
2980 tsubst_flags_t complain)
2982 struct z_candidate *candidates, *cand;
2987 args = resolve_args (args);
2988 if (args == error_mark_node)
2989 return error_mark_node;
2991 /* If this function was found without using argument dependent
2992 lookup, then we want to ignore any undeclared friend
2998 fn = remove_hidden_names (fn);
3001 if (complain & tf_error)
3002 error ("no matching function for call to %<%D(%A)%>",
3003 DECL_NAME (OVL_CURRENT (orig_fn)), args);
3004 return error_mark_node;
3008 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3009 p = conversion_obstack_alloc (0);
3011 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
3015 if (complain & tf_error)
3017 if (!any_viable_p && candidates && ! candidates->next)
3018 return cp_build_function_call (candidates->fn, args, complain);
3019 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3020 fn = TREE_OPERAND (fn, 0);
3022 error ("no matching function for call to %<%D(%A)%>",
3023 DECL_NAME (OVL_CURRENT (fn)), args);
3025 error ("call of overloaded %<%D(%A)%> is ambiguous",
3026 DECL_NAME (OVL_CURRENT (fn)), args);
3028 print_z_candidates (candidates);
3030 result = error_mark_node;
3033 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3035 /* Free all the conversions we allocated. */
3036 obstack_free (&conversion_obstack, p);
3041 /* Build a call to a global operator new. FNNAME is the name of the
3042 operator (either "operator new" or "operator new[]") and ARGS are
3043 the arguments provided. *SIZE points to the total number of bytes
3044 required by the allocation, and is updated if that is changed here.
3045 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
3046 function determines that no cookie should be used, after all,
3047 *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be
3048 set, upon return, to the allocation function called. */
3051 build_operator_new_call (tree fnname, tree args,
3052 tree *size, tree *cookie_size,
3056 struct z_candidate *candidates;
3057 struct z_candidate *cand;
3062 args = tree_cons (NULL_TREE, *size, args);
3063 args = resolve_args (args);
3064 if (args == error_mark_node)
3071 If this lookup fails to find the name, or if the allocated type
3072 is not a class type, the allocation function's name is looked
3073 up in the global scope.
3075 we disregard block-scope declarations of "operator new". */
3076 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
3078 /* Figure out what function is being called. */
3079 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
3081 /* If no suitable function could be found, issue an error message
3086 error ("no matching function for call to %<%D(%A)%>",
3087 DECL_NAME (OVL_CURRENT (fns)), args);
3089 error ("call of overloaded %<%D(%A)%> is ambiguous",
3090 DECL_NAME (OVL_CURRENT (fns)), args);
3092 print_z_candidates (candidates);
3093 return error_mark_node;
3096 /* If a cookie is required, add some extra space. Whether
3097 or not a cookie is required cannot be determined until
3098 after we know which function was called. */
3101 bool use_cookie = true;
3102 if (!abi_version_at_least (2))
3104 tree placement = TREE_CHAIN (args);
3105 /* In G++ 3.2, the check was implemented incorrectly; it
3106 looked at the placement expression, rather than the
3107 type of the function. */
3108 if (placement && !TREE_CHAIN (placement)
3109 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
3117 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3118 /* Skip the size_t parameter. */
3119 arg_types = TREE_CHAIN (arg_types);
3120 /* Check the remaining parameters (if any). */
3122 && TREE_CHAIN (arg_types) == void_list_node
3123 && same_type_p (TREE_VALUE (arg_types),
3127 /* If we need a cookie, adjust the number of bytes allocated. */
3130 /* Update the total size. */
3131 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3132 /* Update the argument list to reflect the adjusted size. */
3133 TREE_VALUE (args) = *size;
3136 *cookie_size = NULL_TREE;
3139 /* Tell our caller which function we decided to call. */
3143 /* Build the CALL_EXPR. */
3144 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3148 build_object_call (tree obj, tree args, tsubst_flags_t complain)
3150 struct z_candidate *candidates = 0, *cand;
3151 tree fns, convs, mem_args = NULL_TREE;
3152 tree type = TREE_TYPE (obj);
3154 tree result = NULL_TREE;
3157 if (TYPE_PTRMEMFUNC_P (type))
3159 if (complain & tf_error)
3160 /* It's no good looking for an overloaded operator() on a
3161 pointer-to-member-function. */
3162 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3163 return error_mark_node;
3166 if (TYPE_BINFO (type))
3168 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3169 if (fns == error_mark_node)
3170 return error_mark_node;
3175 args = resolve_args (args);
3177 if (args == error_mark_node)
3178 return error_mark_node;
3180 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3181 p = conversion_obstack_alloc (0);
3185 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3186 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
3188 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3190 tree fn = OVL_CURRENT (fns);
3191 if (TREE_CODE (fn) == TEMPLATE_DECL)
3192 add_template_candidate (&candidates, fn, base, NULL_TREE,
3193 mem_args, NULL_TREE,
3196 LOOKUP_NORMAL, DEDUCE_CALL);
3198 add_function_candidate
3199 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
3200 TYPE_BINFO (type), LOOKUP_NORMAL);
3204 convs = lookup_conversions (type);
3206 for (; convs; convs = TREE_CHAIN (convs))
3208 tree fns = TREE_VALUE (convs);
3209 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
3211 if ((TREE_CODE (totype) == POINTER_TYPE
3212 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3213 || (TREE_CODE (totype) == REFERENCE_TYPE
3214 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3215 || (TREE_CODE (totype) == REFERENCE_TYPE
3216 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3217 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3218 for (; fns; fns = OVL_NEXT (fns))
3220 tree fn = OVL_CURRENT (fns);
3221 if (TREE_CODE (fn) == TEMPLATE_DECL)
3222 add_template_conv_candidate
3223 (&candidates, fn, obj, args, totype,
3224 /*access_path=*/NULL_TREE,
3225 /*conversion_path=*/NULL_TREE);
3227 add_conv_candidate (&candidates, fn, obj, args,
3228 /*conversion_path=*/NULL_TREE,
3229 /*access_path=*/NULL_TREE);
3233 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3236 if (complain & tf_error)
3238 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3239 print_z_candidates (candidates);
3241 result = error_mark_node;
3245 cand = tourney (candidates);
3248 if (complain & tf_error)
3250 error ("call of %<(%T) (%A)%> is ambiguous",
3251 TREE_TYPE (obj), args);
3252 print_z_candidates (candidates);
3254 result = error_mark_node;
3256 /* Since cand->fn will be a type, not a function, for a conversion
3257 function, we must be careful not to unconditionally look at
3259 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3260 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3261 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3264 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3266 obj = convert_from_reference (obj);
3267 result = cp_build_function_call (obj, args, complain);
3271 /* Free all the conversions we allocated. */
3272 obstack_free (&conversion_obstack, p);
3278 op_error (enum tree_code code, enum tree_code code2,
3279 tree arg1, tree arg2, tree arg3, const char *problem)
3283 if (code == MODIFY_EXPR)
3284 opname = assignment_operator_name_info[code2].name;
3286 opname = operator_name_info[code].name;
3291 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3292 problem, arg1, arg2, arg3);
3295 case POSTINCREMENT_EXPR:
3296 case POSTDECREMENT_EXPR:
3297 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3301 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3306 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3311 error ("%s for %<operator%s%> in %<%E %s %E%>",
3312 problem, opname, arg1, opname, arg2);
3314 error ("%s for %<operator%s%> in %<%s%E%>",
3315 problem, opname, opname, arg1);
3320 /* Return the implicit conversion sequence that could be used to
3321 convert E1 to E2 in [expr.cond]. */
3324 conditional_conversion (tree e1, tree e2)
3326 tree t1 = non_reference (TREE_TYPE (e1));
3327 tree t2 = non_reference (TREE_TYPE (e2));
3333 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3334 implicitly converted (clause _conv_) to the type "reference to
3335 T2", subject to the constraint that in the conversion the
3336 reference must bind directly (_dcl.init.ref_) to E1. */
3337 if (real_lvalue_p (e2))
3339 conv = implicit_conversion (build_reference_type (t2),
3343 LOOKUP_NO_TEMP_BIND);
3350 If E1 and E2 have class type, and the underlying class types are
3351 the same or one is a base class of the other: E1 can be converted
3352 to match E2 if the class of T2 is the same type as, or a base
3353 class of, the class of T1, and the cv-qualification of T2 is the
3354 same cv-qualification as, or a greater cv-qualification than, the
3355 cv-qualification of T1. If the conversion is applied, E1 is
3356 changed to an rvalue of type T2 that still refers to the original
3357 source class object (or the appropriate subobject thereof). */
3358 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3359 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3361 if (good_base && at_least_as_qualified_p (t2, t1))
3363 conv = build_identity_conv (t1, e1);
3364 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3365 TYPE_MAIN_VARIANT (t2)))
3366 conv = build_conv (ck_base, t2, conv);
3368 conv = build_conv (ck_rvalue, t2, conv);
3377 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3378 converted to the type that expression E2 would have if E2 were
3379 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3380 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3384 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3385 arguments to the conditional expression. */
3388 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3389 tsubst_flags_t complain)
3393 tree result = NULL_TREE;
3394 tree result_type = NULL_TREE;
3395 bool lvalue_p = true;
3396 struct z_candidate *candidates = 0;
3397 struct z_candidate *cand;
3400 /* As a G++ extension, the second argument to the conditional can be
3401 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3402 c'.) If the second operand is omitted, make sure it is
3403 calculated only once. */
3406 if (complain & tf_error)
3407 pedwarn (OPT_pedantic,
3408 "ISO C++ forbids omitting the middle term of a ?: expression");
3410 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3411 if (real_lvalue_p (arg1))
3412 arg2 = arg1 = stabilize_reference (arg1);
3414 arg2 = arg1 = save_expr (arg1);
3419 The first expression is implicitly converted to bool (clause
3421 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3423 /* If something has already gone wrong, just pass that fact up the
3425 if (error_operand_p (arg1)
3426 || error_operand_p (arg2)
3427 || error_operand_p (arg3))
3428 return error_mark_node;
3432 If either the second or the third operand has type (possibly
3433 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3434 array-to-pointer (_conv.array_), and function-to-pointer
3435 (_conv.func_) standard conversions are performed on the second
3436 and third operands. */
3437 arg2_type = unlowered_expr_type (arg2);
3438 arg3_type = unlowered_expr_type (arg3);
3439 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3441 /* Do the conversions. We don't these for `void' type arguments
3442 since it can't have any effect and since decay_conversion
3443 does not handle that case gracefully. */
3444 if (!VOID_TYPE_P (arg2_type))
3445 arg2 = decay_conversion (arg2);
3446 if (!VOID_TYPE_P (arg3_type))
3447 arg3 = decay_conversion (arg3);
3448 arg2_type = TREE_TYPE (arg2);
3449 arg3_type = TREE_TYPE (arg3);
3453 One of the following shall hold:
3455 --The second or the third operand (but not both) is a
3456 throw-expression (_except.throw_); the result is of the
3457 type of the other and is an rvalue.
3459 --Both the second and the third operands have type void; the
3460 result is of type void and is an rvalue.
3462 We must avoid calling force_rvalue for expressions of type
3463 "void" because it will complain that their value is being
3465 if (TREE_CODE (arg2) == THROW_EXPR
3466 && TREE_CODE (arg3) != THROW_EXPR)
3468 if (!VOID_TYPE_P (arg3_type))
3469 arg3 = force_rvalue (arg3);
3470 arg3_type = TREE_TYPE (arg3);
3471 result_type = arg3_type;
3473 else if (TREE_CODE (arg2) != THROW_EXPR
3474 && TREE_CODE (arg3) == THROW_EXPR)
3476 if (!VOID_TYPE_P (arg2_type))
3477 arg2 = force_rvalue (arg2);
3478 arg2_type = TREE_TYPE (arg2);
3479 result_type = arg2_type;
3481 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3482 result_type = void_type_node;
3485 if (complain & tf_error)
3487 if (VOID_TYPE_P (arg2_type))
3488 error ("second operand to the conditional operator "
3489 "is of type %<void%>, "
3490 "but the third operand is neither a throw-expression "
3491 "nor of type %<void%>");
3493 error ("third operand to the conditional operator "
3494 "is of type %<void%>, "
3495 "but the second operand is neither a throw-expression "
3496 "nor of type %<void%>");
3498 return error_mark_node;
3502 goto valid_operands;
3506 Otherwise, if the second and third operand have different types,
3507 and either has (possibly cv-qualified) class type, an attempt is
3508 made to convert each of those operands to the type of the other. */
3509 else if (!same_type_p (arg2_type, arg3_type)
3510 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3515 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3516 p = conversion_obstack_alloc (0);
3518 conv2 = conditional_conversion (arg2, arg3);
3519 conv3 = conditional_conversion (arg3, arg2);
3523 If both can be converted, or one can be converted but the
3524 conversion is ambiguous, the program is ill-formed. If
3525 neither can be converted, the operands are left unchanged and
3526 further checking is performed as described below. If exactly
3527 one conversion is possible, that conversion is applied to the
3528 chosen operand and the converted operand is used in place of
3529 the original operand for the remainder of this section. */
3530 if ((conv2 && !conv2->bad_p
3531 && conv3 && !conv3->bad_p)
3532 || (conv2 && conv2->kind == ck_ambig)
3533 || (conv3 && conv3->kind == ck_ambig))
3535 error ("operands to ?: have different types %qT and %qT",
3536 arg2_type, arg3_type);
3537 result = error_mark_node;
3539 else if (conv2 && (!conv2->bad_p || !conv3))
3541 arg2 = convert_like (conv2, arg2, complain);
3542 arg2 = convert_from_reference (arg2);
3543 arg2_type = TREE_TYPE (arg2);
3544 /* Even if CONV2 is a valid conversion, the result of the
3545 conversion may be invalid. For example, if ARG3 has type
3546 "volatile X", and X does not have a copy constructor
3547 accepting a "volatile X&", then even if ARG2 can be
3548 converted to X, the conversion will fail. */
3549 if (error_operand_p (arg2))
3550 result = error_mark_node;
3552 else if (conv3 && (!conv3->bad_p || !conv2))
3554 arg3 = convert_like (conv3, arg3, complain);
3555 arg3 = convert_from_reference (arg3);
3556 arg3_type = TREE_TYPE (arg3);
3557 if (error_operand_p (arg3))
3558 result = error_mark_node;
3561 /* Free all the conversions we allocated. */
3562 obstack_free (&conversion_obstack, p);
3567 /* If, after the conversion, both operands have class type,
3568 treat the cv-qualification of both operands as if it were the
3569 union of the cv-qualification of the operands.
3571 The standard is not clear about what to do in this
3572 circumstance. For example, if the first operand has type
3573 "const X" and the second operand has a user-defined
3574 conversion to "volatile X", what is the type of the second
3575 operand after this step? Making it be "const X" (matching
3576 the first operand) seems wrong, as that discards the
3577 qualification without actually performing a copy. Leaving it
3578 as "volatile X" seems wrong as that will result in the
3579 conditional expression failing altogether, even though,
3580 according to this step, the one operand could be converted to
3581 the type of the other. */
3582 if ((conv2 || conv3)
3583 && CLASS_TYPE_P (arg2_type)
3584 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3585 arg2_type = arg3_type =
3586 cp_build_qualified_type (arg2_type,
3587 TYPE_QUALS (arg2_type)
3588 | TYPE_QUALS (arg3_type));
3593 If the second and third operands are lvalues and have the same
3594 type, the result is of that type and is an lvalue. */
3595 if (real_lvalue_p (arg2)
3596 && real_lvalue_p (arg3)
3597 && same_type_p (arg2_type, arg3_type))
3599 result_type = arg2_type;
3600 goto valid_operands;
3605 Otherwise, the result is an rvalue. If the second and third
3606 operand do not have the same type, and either has (possibly
3607 cv-qualified) class type, overload resolution is used to
3608 determine the conversions (if any) to be applied to the operands
3609 (_over.match.oper_, _over.built_). */
3611 if (!same_type_p (arg2_type, arg3_type)
3612 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3618 /* Rearrange the arguments so that add_builtin_candidate only has
3619 to know about two args. In build_builtin_candidates, the
3620 arguments are unscrambled. */
3624 add_builtin_candidates (&candidates,
3627 ansi_opname (COND_EXPR),
3633 If the overload resolution fails, the program is
3635 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3638 if (complain & tf_error)
3640 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3641 print_z_candidates (candidates);
3643 return error_mark_node;
3645 cand = tourney (candidates);
3648 if (complain & tf_error)
3650 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3651 print_z_candidates (candidates);
3653 return error_mark_node;
3658 Otherwise, the conversions thus determined are applied, and
3659 the converted operands are used in place of the original
3660 operands for the remainder of this section. */
3661 conv = cand->convs[0];
3662 arg1 = convert_like (conv, arg1, complain);
3663 conv = cand->convs[1];
3664 arg2 = convert_like (conv, arg2, complain);
3665 conv = cand->convs[2];
3666 arg3 = convert_like (conv, arg3, complain);
3671 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3672 and function-to-pointer (_conv.func_) standard conversions are
3673 performed on the second and third operands.
3675 We need to force the lvalue-to-rvalue conversion here for class types,
3676 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3677 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3680 arg2 = force_rvalue (arg2);
3681 if (!CLASS_TYPE_P (arg2_type))
3682 arg2_type = TREE_TYPE (arg2);
3684 arg3 = force_rvalue (arg3);
3685 if (!CLASS_TYPE_P (arg2_type))
3686 arg3_type = TREE_TYPE (arg3);
3688 if (arg2 == error_mark_node || arg3 == error_mark_node)
3689 return error_mark_node;
3693 After those conversions, one of the following shall hold:
3695 --The second and third operands have the same type; the result is of
3697 if (same_type_p (arg2_type, arg3_type))
3698 result_type = arg2_type;
3701 --The second and third operands have arithmetic or enumeration
3702 type; the usual arithmetic conversions are performed to bring
3703 them to a common type, and the result is of that type. */
3704 else if ((ARITHMETIC_TYPE_P (arg2_type)
3705 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3706 && (ARITHMETIC_TYPE_P (arg3_type)
3707 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3709 /* In this case, there is always a common type. */
3710 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3713 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3714 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3716 if (complain & tf_warning)
3718 "enumeral mismatch in conditional expression: %qT vs %qT",
3719 arg2_type, arg3_type);
3721 else if (extra_warnings
3722 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3723 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3724 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3725 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3727 if (complain & tf_warning)
3729 "enumeral and non-enumeral type in conditional expression");
3732 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3733 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3737 --The second and third operands have pointer type, or one has
3738 pointer type and the other is a null pointer constant; pointer
3739 conversions (_conv.ptr_) and qualification conversions
3740 (_conv.qual_) are performed to bring them to their composite
3741 pointer type (_expr.rel_). The result is of the composite
3744 --The second and third operands have pointer to member type, or
3745 one has pointer to member type and the other is a null pointer
3746 constant; pointer to member conversions (_conv.mem_) and
3747 qualification conversions (_conv.qual_) are performed to bring
3748 them to a common type, whose cv-qualification shall match the
3749 cv-qualification of either the second or the third operand.
3750 The result is of the common type. */
3751 else if ((null_ptr_cst_p (arg2)
3752 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3753 || (null_ptr_cst_p (arg3)
3754 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3755 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3756 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3757 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3759 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3760 arg3, "conditional expression",
3762 if (result_type == error_mark_node)
3763 return error_mark_node;
3764 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3765 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3770 if (complain & tf_error)
3771 error ("operands to ?: have different types %qT and %qT",
3772 arg2_type, arg3_type);
3773 return error_mark_node;
3777 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3779 /* We can't use result_type below, as fold might have returned a
3784 /* Expand both sides into the same slot, hopefully the target of
3785 the ?: expression. We used to check for TARGET_EXPRs here,
3786 but now we sometimes wrap them in NOP_EXPRs so the test would
3788 if (CLASS_TYPE_P (TREE_TYPE (result)))
3789 result = get_target_expr (result);
3790 /* If this expression is an rvalue, but might be mistaken for an
3791 lvalue, we must add a NON_LVALUE_EXPR. */
3792 result = rvalue (result);
3798 /* OPERAND is an operand to an expression. Perform necessary steps
3799 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3803 prep_operand (tree operand)
3807 if (CLASS_TYPE_P (TREE_TYPE (operand))
3808 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3809 /* Make sure the template type is instantiated now. */
3810 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3816 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3817 OVERLOAD) to the CANDIDATES, returning an updated list of
3818 CANDIDATES. The ARGS are the arguments provided to the call,
3819 without any implicit object parameter. The EXPLICIT_TARGS are
3820 explicit template arguments provided. TEMPLATE_ONLY is true if
3821 only template functions should be considered. CONVERSION_PATH,
3822 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3825 add_candidates (tree fns, tree args,
3826 tree explicit_targs, bool template_only,
3827 tree conversion_path, tree access_path,
3829 struct z_candidate **candidates)
3832 tree non_static_args;
3834 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3835 /* Delay creating the implicit this parameter until it is needed. */
3836 non_static_args = NULL_TREE;
3843 fn = OVL_CURRENT (fns);
3844 /* Figure out which set of arguments to use. */
3845 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3847 /* If this function is a non-static member, prepend the implicit
3848 object parameter. */
3849 if (!non_static_args)
3850 non_static_args = tree_cons (NULL_TREE,
3851 build_this (TREE_VALUE (args)),
3853 fn_args = non_static_args;
3856 /* Otherwise, just use the list of arguments provided. */
3859 if (TREE_CODE (fn) == TEMPLATE_DECL)
3860 add_template_candidate (candidates,
3870 else if (!template_only)
3871 add_function_candidate (candidates,
3878 fns = OVL_NEXT (fns);
3883 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3884 bool *overloaded_p, tsubst_flags_t complain)
3886 struct z_candidate *candidates = 0, *cand;
3887 tree arglist, fnname;
3889 tree result = NULL_TREE;
3890 bool result_valid_p = false;
3891 enum tree_code code2 = NOP_EXPR;
3896 bool expl_eq_arg1 = false;
3898 if (error_operand_p (arg1)
3899 || error_operand_p (arg2)
3900 || error_operand_p (arg3))
3901 return error_mark_node;
3903 if (code == MODIFY_EXPR)
3905 code2 = TREE_CODE (arg3);
3907 fnname = ansi_assopname (code2);
3910 fnname = ansi_opname (code);
3912 arg1 = prep_operand (arg1);
3918 case VEC_DELETE_EXPR:
3920 /* Use build_op_new_call and build_op_delete_call instead. */
3924 return build_object_call (arg1, arg2, complain);
3926 case TRUTH_ORIF_EXPR:
3927 case TRUTH_ANDIF_EXPR:
3928 case TRUTH_AND_EXPR:
3930 if (COMPARISON_CLASS_P (arg1))
3931 expl_eq_arg1 = true;
3936 arg2 = prep_operand (arg2);
3937 arg3 = prep_operand (arg3);
3939 if (code == COND_EXPR)
3941 if (arg2 == NULL_TREE
3942 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3943 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3944 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3945 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3948 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3949 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3952 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3953 arg2 = integer_zero_node;
3955 arglist = NULL_TREE;
3957 arglist = tree_cons (NULL_TREE, arg3, arglist);
3959 arglist = tree_cons (NULL_TREE, arg2, arglist);
3960 arglist = tree_cons (NULL_TREE, arg1, arglist);
3962 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3963 p = conversion_obstack_alloc (0);
3965 /* Add namespace-scope operators to the list of functions to
3967 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3968 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3969 flags, &candidates);
3970 /* Add class-member operators to the candidate set. */
3971 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3975 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3976 if (fns == error_mark_node)
3978 result = error_mark_node;
3979 goto user_defined_result_ready;
3982 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3984 BASELINK_BINFO (fns),
3985 TYPE_BINFO (TREE_TYPE (arg1)),
3986 flags, &candidates);
3989 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3990 to know about two args; a builtin candidate will always have a first
3991 parameter of type bool. We'll handle that in
3992 build_builtin_candidate. */
3993 if (code == COND_EXPR)
4003 args[2] = NULL_TREE;
4006 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4012 /* For these, the built-in candidates set is empty
4013 [over.match.oper]/3. We don't want non-strict matches
4014 because exact matches are always possible with built-in
4015 operators. The built-in candidate set for COMPONENT_REF
4016 would be empty too, but since there are no such built-in
4017 operators, we accept non-strict matches for them. */
4022 strict_p = pedantic;
4026 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4031 case POSTINCREMENT_EXPR:
4032 case POSTDECREMENT_EXPR:
4033 /* Don't try anything fancy if we're not allowed to produce
4035 if (!(complain & tf_error))
4036 return error_mark_node;
4038 /* Look for an `operator++ (int)'. If they didn't have
4039 one, then we fall back to the old way of doing things. */
4040 if (flags & LOOKUP_COMPLAIN)
4041 permerror (input_location, "no %<%D(int)%> declared for postfix %qs, "
4042 "trying prefix operator instead",
4044 operator_name_info[code].name);
4045 if (code == POSTINCREMENT_EXPR)
4046 code = PREINCREMENT_EXPR;
4048 code = PREDECREMENT_EXPR;
4049 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4050 overloaded_p, complain);
4053 /* The caller will deal with these. */
4058 result_valid_p = true;
4062 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4064 op_error (code, code2, arg1, arg2, arg3, "no match");
4065 print_z_candidates (candidates);
4067 result = error_mark_node;
4073 cand = tourney (candidates);
4076 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4078 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4079 print_z_candidates (candidates);
4081 result = error_mark_node;
4083 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4086 *overloaded_p = true;
4088 if (resolve_args (arglist) == error_mark_node)
4089 result = error_mark_node;
4091 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4095 /* Give any warnings we noticed during overload resolution. */
4096 if (cand->warnings && (complain & tf_warning))
4098 struct candidate_warning *w;
4099 for (w = cand->warnings; w; w = w->next)
4100 joust (cand, w->loser, 1);
4103 /* Check for comparison of different enum types. */
4112 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4113 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4114 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4115 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4116 && (complain & tf_warning))
4118 warning (OPT_Wenum_compare,
4119 "comparison between %q#T and %q#T",
4120 TREE_TYPE (arg1), TREE_TYPE (arg2));
4127 /* We need to strip any leading REF_BIND so that bitfields
4128 don't cause errors. This should not remove any important
4129 conversions, because builtins don't apply to class
4130 objects directly. */
4131 conv = cand->convs[0];
4132 if (conv->kind == ck_ref_bind)
4133 conv = conv->u.next;
4134 arg1 = convert_like (conv, arg1, complain);
4137 conv = cand->convs[1];
4138 if (conv->kind == ck_ref_bind)
4139 conv = conv->u.next;
4140 arg2 = convert_like (conv, arg2, complain);
4144 conv = cand->convs[2];
4145 if (conv->kind == ck_ref_bind)
4146 conv = conv->u.next;
4147 arg3 = convert_like (conv, arg3, complain);
4152 if (complain & tf_warning)
4153 warn_logical_operator (code, arg1, arg2);
4154 expl_eq_arg1 = true;
4159 user_defined_result_ready:
4161 /* Free all the conversions we allocated. */
4162 obstack_free (&conversion_obstack, p);
4164 if (result || result_valid_p)
4171 return cp_build_modify_expr (arg1, code2, arg2, complain);
4174 return cp_build_indirect_ref (arg1, "unary *", complain);
4176 case TRUTH_ANDIF_EXPR:
4177 case TRUTH_ORIF_EXPR:
4178 case TRUTH_AND_EXPR:
4181 warn_logical_operator (code, arg1, arg2);
4185 case TRUNC_DIV_EXPR:
4196 case TRUNC_MOD_EXPR:
4200 return cp_build_binary_op (code, arg1, arg2, complain);
4202 case UNARY_PLUS_EXPR:
4205 case TRUTH_NOT_EXPR:
4206 case PREINCREMENT_EXPR:
4207 case POSTINCREMENT_EXPR:
4208 case PREDECREMENT_EXPR:
4209 case POSTDECREMENT_EXPR:
4212 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4215 return build_array_ref (arg1, arg2);
4218 return build_conditional_expr (arg1, arg2, arg3, complain);
4221 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4225 /* The caller will deal with these. */
4237 /* Build a call to operator delete. This has to be handled very specially,
4238 because the restrictions on what signatures match are different from all
4239 other call instances. For a normal delete, only a delete taking (void *)
4240 or (void *, size_t) is accepted. For a placement delete, only an exact
4241 match with the placement new is accepted.
4243 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4244 ADDR is the pointer to be deleted.
4245 SIZE is the size of the memory block to be deleted.
4246 GLOBAL_P is true if the delete-expression should not consider
4247 class-specific delete operators.
4248 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4250 If this call to "operator delete" is being generated as part to
4251 deallocate memory allocated via a new-expression (as per [expr.new]
4252 which requires that if the initialization throws an exception then
4253 we call a deallocation function), then ALLOC_FN is the allocation
4257 build_op_delete_call (enum tree_code code, tree addr, tree size,
4258 bool global_p, tree placement,
4261 tree fn = NULL_TREE;
4262 tree fns, fnname, argtypes, type;
4265 if (addr == error_mark_node)
4266 return error_mark_node;
4268 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4270 fnname = ansi_opname (code);
4272 if (CLASS_TYPE_P (type)
4273 && COMPLETE_TYPE_P (complete_type (type))
4277 If the result of the lookup is ambiguous or inaccessible, or if
4278 the lookup selects a placement deallocation function, the
4279 program is ill-formed.
4281 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4283 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4284 if (fns == error_mark_node)
4285 return error_mark_node;
4290 if (fns == NULL_TREE)
4291 fns = lookup_name_nonclass (fnname);
4293 /* Strip const and volatile from addr. */
4294 addr = cp_convert (ptr_type_node, addr);
4298 /* Get the parameter types for the allocation function that is
4300 gcc_assert (alloc_fn != NULL_TREE);
4301 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4305 /* First try it without the size argument. */
4306 argtypes = void_list_node;
4309 /* We make two tries at finding a matching `operator delete'. On
4310 the first pass, we look for a one-operator (or placement)
4311 operator delete. If we're not doing placement delete, then on
4312 the second pass we look for a two-argument delete. */
4313 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4315 /* Go through the `operator delete' functions looking for one
4316 with a matching type. */
4317 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4323 /* The first argument must be "void *". */
4324 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4325 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4328 /* On the first pass, check the rest of the arguments. */
4334 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4342 /* On the second pass, look for a function with exactly two
4343 arguments: "void *" and "size_t". */
4345 /* For "operator delete(void *, ...)" there will be
4346 no second argument, but we will not get an exact
4349 && same_type_p (TREE_VALUE (t), size_type_node)
4350 && TREE_CHAIN (t) == void_list_node)
4354 /* If we found a match, we're done. */
4359 /* If we have a matching function, call it. */
4362 /* Make sure we have the actual function, and not an
4364 fn = OVL_CURRENT (fn);
4366 /* If the FN is a member function, make sure that it is
4368 if (DECL_CLASS_SCOPE_P (fn))
4369 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4373 /* The placement args might not be suitable for overload
4374 resolution at this point, so build the call directly. */
4375 int nargs = call_expr_nargs (placement);
4376 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4379 for (i = 1; i < nargs; i++)
4380 argarray[i] = CALL_EXPR_ARG (placement, i);
4382 return build_cxx_call (fn, nargs, argarray);
4388 args = tree_cons (NULL_TREE, addr, NULL_TREE);
4390 args = tree_cons (NULL_TREE, addr,
4391 build_tree_list (NULL_TREE, size));
4392 return cp_build_function_call (fn, args, tf_warning_or_error);
4398 If no unambiguous matching deallocation function can be found,
4399 propagating the exception does not cause the object's memory to
4404 warning (0, "no corresponding deallocation function for %qD",
4409 error ("no suitable %<operator %s%> for %qT",
4410 operator_name_info[(int)code].name, type);
4411 return error_mark_node;
4414 /* If the current scope isn't allowed to access DECL along
4415 BASETYPE_PATH, give an error. The most derived class in
4416 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4417 the declaration to use in the error diagnostic. */
4420 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4422 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4424 if (!accessible_p (basetype_path, decl, true))
4426 if (TREE_PRIVATE (decl))
4427 error ("%q+#D is private", diag_decl);
4428 else if (TREE_PROTECTED (decl))
4429 error ("%q+#D is protected", diag_decl);
4431 error ("%q+#D is inaccessible", diag_decl);
4432 error ("within this context");
4439 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4440 bitwise or of LOOKUP_* values. If any errors are warnings are
4441 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4442 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4446 build_temp (tree expr, tree type, int flags,
4447 diagnostic_t *diagnostic_kind)
4451 savew = warningcount, savee = errorcount;
4452 expr = build_special_member_call (NULL_TREE,
4453 complete_ctor_identifier,
4454 build_tree_list (NULL_TREE, expr),
4455 type, flags, tf_warning_or_error);
4456 if (warningcount > savew)
4457 *diagnostic_kind = DK_WARNING;
4458 else if (errorcount > savee)
4459 *diagnostic_kind = DK_ERROR;
4461 *diagnostic_kind = 0;
4465 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4466 EXPR is implicitly converted to type TOTYPE.
4467 FN and ARGNUM are used for diagnostics. */
4470 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4472 tree t = non_reference (totype);
4474 /* Issue warnings about peculiar, but valid, uses of NULL. */
4475 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4478 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4481 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4484 /* Issue warnings if "false" is converted to a NULL pointer */
4485 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4486 warning (OPT_Wconversion,
4487 "converting %<false%> to pointer type for argument %P of %qD",
4491 /* Perform the conversions in CONVS on the expression EXPR. FN and
4492 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4493 indicates the `this' argument of a method. INNER is nonzero when
4494 being called to continue a conversion chain. It is negative when a
4495 reference binding will be applied, positive otherwise. If
4496 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4497 conversions will be emitted if appropriate. If C_CAST_P is true,
4498 this conversion is coming from a C-style cast; in that case,
4499 conversions to inaccessible bases are permitted. */
4502 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4503 int inner, bool issue_conversion_warnings,
4504 bool c_cast_p, tsubst_flags_t complain)
4506 tree totype = convs->type;
4507 diagnostic_t diag_kind;
4511 && convs->kind != ck_user
4512 && convs->kind != ck_ambig
4513 && convs->kind != ck_ref_bind
4514 && convs->kind != ck_rvalue
4515 && convs->kind != ck_base)
4517 conversion *t = convs;
4518 for (; t; t = convs->u.next)
4520 if (t->kind == ck_user || !t->bad_p)
4522 expr = convert_like_real (t, expr, fn, argnum, 1,
4523 /*issue_conversion_warnings=*/false,
4528 else if (t->kind == ck_ambig)
4529 return convert_like_real (t, expr, fn, argnum, 1,
4530 /*issue_conversion_warnings=*/false,
4533 else if (t->kind == ck_identity)
4536 if (complain & tf_error)
4538 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4540 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4543 return error_mark_node;
4545 return cp_convert (totype, expr);
4548 if (issue_conversion_warnings && (complain & tf_warning))
4549 conversion_null_warnings (totype, expr, fn, argnum);
4551 switch (convs->kind)
4555 struct z_candidate *cand = convs->cand;
4556 tree convfn = cand->fn;
4559 /* When converting from an init list we consider explicit
4560 constructors, but actually trying to call one is an error. */
4561 if (DECL_NONCONVERTING_P (convfn))
4563 if (complain & tf_error)
4564 error ("converting to %qT from initializer list would use "
4565 "explicit constructor %qD", totype, convfn);
4567 return error_mark_node;
4570 /* Set user_conv_p on the argument conversions, so rvalue/base
4571 handling knows not to allow any more UDCs. */
4572 for (i = 0; i < cand->num_convs; ++i)
4573 cand->convs[i]->user_conv_p = true;
4575 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4577 /* If this is a constructor or a function returning an aggr type,
4578 we need to build up a TARGET_EXPR. */
4579 if (DECL_CONSTRUCTOR_P (convfn))
4580 expr = build_cplus_new (totype, expr);
4585 if (type_unknown_p (expr))
4586 expr = instantiate_type (totype, expr, complain);
4587 /* Convert a constant to its underlying value, unless we are
4588 about to bind it to a reference, in which case we need to
4589 leave it as an lvalue. */
4592 expr = decl_constant_value (expr);
4593 if (expr == null_node && INTEGRAL_TYPE_P (totype))
4594 /* If __null has been converted to an integer type, we do not
4595 want to warn about uses of EXPR as an integer, rather than
4597 expr = build_int_cst (totype, 0);
4601 /* Call build_user_type_conversion again for the error. */
4602 return build_user_type_conversion
4603 (totype, convs->u.expr, LOOKUP_NORMAL);
4607 /* Conversion to std::initializer_list<T>. */
4608 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4609 tree new_ctor = build_constructor (init_list_type_node, NULL);
4610 unsigned len = CONSTRUCTOR_NELTS (expr);
4611 tree array, parms, val;
4614 /* Convert all the elements. */
4615 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4617 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4618 1, false, false, complain);
4619 if (sub == error_mark_node)
4621 check_narrowing (TREE_TYPE (sub), val);
4622 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4624 /* Build up the array. */
4625 elttype = cp_build_qualified_type
4626 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4627 array = build_array_of_n_type (elttype, len);
4628 array = finish_compound_literal (array, new_ctor);
4630 parms = build_tree_list (NULL_TREE, size_int (len));
4631 parms = tree_cons (NULL_TREE, decay_conversion (array), parms);
4632 /* Call the private constructor. */
4633 push_deferring_access_checks (dk_no_check);
4634 new_ctor = build_special_member_call
4635 (NULL_TREE, complete_ctor_identifier, parms, totype, 0, complain);
4636 pop_deferring_access_checks ();
4637 return build_cplus_new (totype, new_ctor);
4641 return get_target_expr (digest_init (totype, expr));
4647 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4648 convs->kind == ck_ref_bind ? -1 : 1,
4649 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4652 if (expr == error_mark_node)
4653 return error_mark_node;
4655 switch (convs->kind)
4658 expr = convert_bitfield_to_declared_type (expr);
4659 if (! MAYBE_CLASS_TYPE_P (totype))
4661 /* Else fall through. */
4663 if (convs->kind == ck_base && !convs->need_temporary_p)
4665 /* We are going to bind a reference directly to a base-class
4666 subobject of EXPR. */
4667 /* Build an expression for `*((base*) &expr)'. */
4668 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4669 expr = convert_to_base (expr, build_pointer_type (totype),
4670 !c_cast_p, /*nonnull=*/true);
4671 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4675 /* Copy-initialization where the cv-unqualified version of the source
4676 type is the same class as, or a derived class of, the class of the
4677 destination [is treated as direct-initialization]. [dcl.init] */
4678 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4679 if (convs->user_conv_p)
4680 /* This conversion is being done in the context of a user-defined
4681 conversion (i.e. the second step of copy-initialization), so
4682 don't allow any more. */
4683 flags |= LOOKUP_NO_CONVERSION;
4684 expr = build_temp (expr, totype, flags, &diag_kind);
4685 if (diag_kind && fn)
4687 if ((complain & tf_error))
4688 emit_diagnostic (diag_kind, input_location, 0,
4689 " initializing argument %P of %qD", argnum, fn);
4690 else if (diag_kind == DK_ERROR)
4691 return error_mark_node;
4693 return build_cplus_new (totype, expr);
4697 tree ref_type = totype;
4699 /* If necessary, create a temporary.
4701 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4702 that need temporaries, even when their types are reference
4703 compatible with the type of reference being bound, so the
4704 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
4706 if (convs->need_temporary_p
4707 || TREE_CODE (expr) == CONSTRUCTOR
4708 || TREE_CODE (expr) == VA_ARG_EXPR)
4710 tree type = convs->u.next->type;
4711 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4713 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4714 && !TYPE_REF_IS_RVALUE (ref_type))
4716 if (complain & tf_error)
4718 /* If the reference is volatile or non-const, we
4719 cannot create a temporary. */
4720 if (lvalue & clk_bitfield)
4721 error ("cannot bind bitfield %qE to %qT",
4723 else if (lvalue & clk_packed)
4724 error ("cannot bind packed field %qE to %qT",
4727 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4729 return error_mark_node;
4731 /* If the source is a packed field, and we must use a copy
4732 constructor, then building the target expr will require
4733 binding the field to the reference parameter to the
4734 copy constructor, and we'll end up with an infinite
4735 loop. If we can use a bitwise copy, then we'll be
4737 if ((lvalue & clk_packed)
4738 && CLASS_TYPE_P (type)
4739 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4741 if (complain & tf_error)
4742 error ("cannot bind packed field %qE to %qT",
4744 return error_mark_node;
4746 if (lvalue & clk_bitfield)
4748 expr = convert_bitfield_to_declared_type (expr);
4749 expr = fold_convert (type, expr);
4751 expr = build_target_expr_with_type (expr, type);
4754 /* Take the address of the thing to which we will bind the
4756 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
4757 if (expr == error_mark_node)
4758 return error_mark_node;
4760 /* Convert it to a pointer to the type referred to by the
4761 reference. This will adjust the pointer if a derived to
4762 base conversion is being performed. */
4763 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4765 /* Convert the pointer to the desired reference type. */
4766 return build_nop (ref_type, expr);
4770 return decay_conversion (expr);
4773 /* Warn about deprecated conversion if appropriate. */
4774 string_conv_p (totype, expr, 1);
4779 expr = convert_to_base (expr, totype, !c_cast_p,
4781 return build_nop (totype, expr);
4784 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4791 if (convs->check_narrowing)
4792 check_narrowing (totype, expr);
4794 if (issue_conversion_warnings)
4795 expr = convert_and_check (totype, expr);
4797 expr = convert (totype, expr);
4802 /* Build a call to __builtin_trap. */
4805 call_builtin_trap (void)
4807 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4809 gcc_assert (fn != NULL);
4810 fn = build_call_n (fn, 0);
4814 /* ARG is being passed to a varargs function. Perform any conversions
4815 required. Return the converted value. */
4818 convert_arg_to_ellipsis (tree arg)
4822 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4823 standard conversions are performed. */
4824 arg = decay_conversion (arg);
4827 If the argument has integral or enumeration type that is subject
4828 to the integral promotions (_conv.prom_), or a floating point
4829 type that is subject to the floating point promotion
4830 (_conv.fpprom_), the value of the argument is converted to the
4831 promoted type before the call. */
4832 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4833 && (TYPE_PRECISION (TREE_TYPE (arg))
4834 < TYPE_PRECISION (double_type_node)))
4835 arg = convert_to_real (double_type_node, arg);
4836 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4837 arg = perform_integral_promotions (arg);
4839 arg = require_complete_type (arg);
4841 if (arg != error_mark_node
4842 && !pod_type_p (TREE_TYPE (arg)))
4844 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4845 here and do a bitwise copy, but now cp_expr_size will abort if we
4847 If the call appears in the context of a sizeof expression,
4848 there is no need to emit a warning, since the expression won't be
4849 evaluated. We keep the builtin_trap just as a safety check. */
4850 if (!skip_evaluation)
4851 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4852 "call will abort at runtime", TREE_TYPE (arg));
4853 arg = call_builtin_trap ();
4854 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4861 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4864 build_x_va_arg (tree expr, tree type)
4866 if (processing_template_decl)
4867 return build_min (VA_ARG_EXPR, type, expr);
4869 type = complete_type_or_else (type, NULL_TREE);
4871 if (expr == error_mark_node || !type)
4872 return error_mark_node;
4874 if (! pod_type_p (type))
4876 /* Remove reference types so we don't ICE later on. */
4877 tree type1 = non_reference (type);
4878 /* Undefined behavior [expr.call] 5.2.2/7. */
4879 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4880 "call will abort at runtime", type);
4881 expr = convert (build_pointer_type (type1), null_node);
4882 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4883 call_builtin_trap (), expr);
4884 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
4888 return build_va_arg (expr, type);
4891 /* TYPE has been given to va_arg. Apply the default conversions which
4892 would have happened when passed via ellipsis. Return the promoted
4893 type, or the passed type if there is no change. */
4896 cxx_type_promotes_to (tree type)
4900 /* Perform the array-to-pointer and function-to-pointer
4902 type = type_decays_to (type);
4904 promote = type_promotes_to (type);
4905 if (same_type_p (type, promote))
4911 /* ARG is a default argument expression being passed to a parameter of
4912 the indicated TYPE, which is a parameter to FN. Do any required
4913 conversions. Return the converted value. */
4915 static GTY(()) VEC(tree,gc) *default_arg_context;
4918 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4923 /* If the ARG is an unparsed default argument expression, the
4924 conversion cannot be performed. */
4925 if (TREE_CODE (arg) == DEFAULT_ARG)
4927 error ("the default argument for parameter %d of %qD has "
4928 "not yet been parsed",
4930 return error_mark_node;
4933 /* Detect recursion. */
4934 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
4937 error ("recursive evaluation of default argument for %q#D", fn);
4938 return error_mark_node;
4940 VEC_safe_push (tree, gc, default_arg_context, fn);
4942 if (fn && DECL_TEMPLATE_INFO (fn))
4943 arg = tsubst_default_argument (fn, type, arg);
4945 arg = break_out_target_exprs (arg);
4947 if (TREE_CODE (arg) == CONSTRUCTOR)
4949 arg = digest_init (type, arg);
4950 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4951 "default argument", fn, parmnum,
4952 tf_warning_or_error);
4956 /* We must make a copy of ARG, in case subsequent processing
4957 alters any part of it. For example, during gimplification a
4958 cast of the form (T) &X::f (where "f" is a member function)
4959 will lead to replacing the PTRMEM_CST for &X::f with a
4960 VAR_DECL. We can avoid the copy for constants, since they
4961 are never modified in place. */
4962 if (!CONSTANT_CLASS_P (arg))
4963 arg = unshare_expr (arg);
4964 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4965 "default argument", fn, parmnum,
4966 tf_warning_or_error);
4967 arg = convert_for_arg_passing (type, arg);
4970 VEC_pop (tree, default_arg_context);
4975 /* Returns the type which will really be used for passing an argument of
4979 type_passed_as (tree type)
4981 /* Pass classes with copy ctors by invisible reference. */
4982 if (TREE_ADDRESSABLE (type))
4984 type = build_reference_type (type);
4985 /* There are no other pointers to this temporary. */
4986 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4988 else if (targetm.calls.promote_prototypes (type)
4989 && INTEGRAL_TYPE_P (type)
4990 && COMPLETE_TYPE_P (type)
4991 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4992 TYPE_SIZE (integer_type_node)))
4993 type = integer_type_node;
4998 /* Actually perform the appropriate conversion. */
5001 convert_for_arg_passing (tree type, tree val)
5005 /* If VAL is a bitfield, then -- since it has already been converted
5006 to TYPE -- it cannot have a precision greater than TYPE.
5008 If it has a smaller precision, we must widen it here. For
5009 example, passing "int f:3;" to a function expecting an "int" will
5010 not result in any conversion before this point.
5012 If the precision is the same we must not risk widening. For
5013 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5014 often have type "int", even though the C++ type for the field is
5015 "long long". If the value is being passed to a function
5016 expecting an "int", then no conversions will be required. But,
5017 if we call convert_bitfield_to_declared_type, the bitfield will
5018 be converted to "long long". */
5019 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5021 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5022 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5024 if (val == error_mark_node)
5026 /* Pass classes with copy ctors by invisible reference. */
5027 else if (TREE_ADDRESSABLE (type))
5028 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5029 else if (targetm.calls.promote_prototypes (type)
5030 && INTEGRAL_TYPE_P (type)
5031 && COMPLETE_TYPE_P (type)
5032 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5033 TYPE_SIZE (integer_type_node)))
5034 val = perform_integral_promotions (val);
5035 if (warn_missing_format_attribute)
5037 tree rhstype = TREE_TYPE (val);
5038 const enum tree_code coder = TREE_CODE (rhstype);
5039 const enum tree_code codel = TREE_CODE (type);
5040 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5042 && check_missing_format_attribute (type, rhstype))
5043 warning (OPT_Wmissing_format_attribute,
5044 "argument of function call might be a candidate for a format attribute");
5049 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5050 which no conversions at all should be done. This is true for some
5051 builtins which don't act like normal functions. */
5054 magic_varargs_p (tree fn)
5056 if (DECL_BUILT_IN (fn))
5057 switch (DECL_FUNCTION_CODE (fn))
5059 case BUILT_IN_CLASSIFY_TYPE:
5060 case BUILT_IN_CONSTANT_P:
5061 case BUILT_IN_NEXT_ARG:
5062 case BUILT_IN_VA_START:
5066 return lookup_attribute ("type generic",
5067 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5073 /* Subroutine of the various build_*_call functions. Overload resolution
5074 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5075 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5076 bitmask of various LOOKUP_* flags which apply to the call itself. */
5079 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5082 tree args = cand->args;
5083 conversion **convs = cand->convs;
5085 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5093 bool already_used = false;
5095 /* In a template, there is no need to perform all of the work that
5096 is normally done. We are only interested in the type of the call
5097 expression, i.e., the return type of the function. Any semantic
5098 errors will be deferred until the template is instantiated. */
5099 if (processing_template_decl)
5103 return_type = TREE_TYPE (TREE_TYPE (fn));
5104 expr = build_call_list (return_type, fn, args);
5105 if (TREE_THIS_VOLATILE (fn) && cfun)
5106 current_function_returns_abnormally = 1;
5107 if (!VOID_TYPE_P (return_type))
5108 require_complete_type (return_type);
5109 return convert_from_reference (expr);
5112 /* Give any warnings we noticed during overload resolution. */
5115 struct candidate_warning *w;
5116 for (w = cand->warnings; w; w = w->next)
5117 joust (cand, w->loser, 1);
5120 if (DECL_FUNCTION_MEMBER_P (fn))
5122 /* If FN is a template function, two cases must be considered.
5127 template <class T> void f();
5129 template <class T> struct B {
5133 struct C : A, B<int> {
5135 using B<int>::g; // #2
5138 In case #1 where `A::f' is a member template, DECL_ACCESS is
5139 recorded in the primary template but not in its specialization.
5140 We check access of FN using its primary template.
5142 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5143 because it is a member of class template B, DECL_ACCESS is
5144 recorded in the specialization `B<int>::g'. We cannot use its
5145 primary template because `B<T>::g' and `B<int>::g' may have
5146 different access. */
5147 if (DECL_TEMPLATE_INFO (fn)
5148 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5149 perform_or_defer_access_check (cand->access_path,
5150 DECL_TI_TEMPLATE (fn), fn);
5152 perform_or_defer_access_check (cand->access_path, fn, fn);
5155 if (args && TREE_CODE (args) != TREE_LIST)
5156 args = build_tree_list (NULL_TREE, args);
5159 /* Find maximum size of vector to hold converted arguments. */
5160 parmlen = list_length (parm);
5161 nargs = list_length (args);
5162 if (parmlen > nargs)
5164 argarray = (tree *) alloca (nargs * sizeof (tree));
5166 /* The implicit parameters to a constructor are not considered by overload
5167 resolution, and must be of the proper type. */
5168 if (DECL_CONSTRUCTOR_P (fn))
5170 argarray[j++] = TREE_VALUE (arg);
5171 arg = TREE_CHAIN (arg);
5172 parm = TREE_CHAIN (parm);
5173 /* We should never try to call the abstract constructor. */
5174 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5176 if (DECL_HAS_VTT_PARM_P (fn))
5178 argarray[j++] = TREE_VALUE (arg);
5179 arg = TREE_CHAIN (arg);
5180 parm = TREE_CHAIN (parm);
5183 /* Bypass access control for 'this' parameter. */
5184 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5186 tree parmtype = TREE_VALUE (parm);
5187 tree argtype = TREE_TYPE (TREE_VALUE (arg));
5191 if (convs[i]->bad_p)
5193 if (complain & tf_error)
5194 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5195 TREE_TYPE (argtype), fn);
5197 return error_mark_node;
5200 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5201 X is called for an object that is not of type X, or of a type
5202 derived from X, the behavior is undefined.
5204 So we can assume that anything passed as 'this' is non-null, and
5205 optimize accordingly. */
5206 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5207 /* Convert to the base in which the function was declared. */
5208 gcc_assert (cand->conversion_path != NULL_TREE);
5209 converted_arg = build_base_path (PLUS_EXPR,
5211 cand->conversion_path,
5213 /* Check that the base class is accessible. */
5214 if (!accessible_base_p (TREE_TYPE (argtype),
5215 BINFO_TYPE (cand->conversion_path), true))
5216 error ("%qT is not an accessible base of %qT",
5217 BINFO_TYPE (cand->conversion_path),
5218 TREE_TYPE (argtype));
5219 /* If fn was found by a using declaration, the conversion path
5220 will be to the derived class, not the base declaring fn. We
5221 must convert from derived to base. */
5222 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5223 TREE_TYPE (parmtype), ba_unique, NULL);
5224 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5227 argarray[j++] = converted_arg;
5228 parm = TREE_CHAIN (parm);
5229 arg = TREE_CHAIN (arg);
5235 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
5237 tree type = TREE_VALUE (parm);
5241 /* Don't make a copy here if build_call is going to. */
5242 if (conv->kind == ck_rvalue
5243 && COMPLETE_TYPE_P (complete_type (type))
5244 && !TREE_ADDRESSABLE (type))
5245 conv = conv->u.next;
5247 val = convert_like_with_context
5248 (conv, TREE_VALUE (arg), fn, i - is_method, complain);
5250 val = convert_for_arg_passing (type, val);
5251 if ((complain == tf_none) && val == error_mark_node)
5252 return error_mark_node;
5254 argarray[j++] = val;
5257 /* Default arguments */
5258 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5259 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5260 TREE_PURPOSE (parm),
5263 for (; arg; arg = TREE_CHAIN (arg))
5265 tree a = TREE_VALUE (arg);
5266 if (magic_varargs_p (fn))
5267 /* Do no conversions for magic varargs. */;
5269 a = convert_arg_to_ellipsis (a);
5273 gcc_assert (j <= nargs);
5276 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5277 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5279 /* Avoid actually calling copy constructors and copy assignment operators,
5282 if (! flag_elide_constructors)
5283 /* Do things the hard way. */;
5284 else if (cand->num_convs == 1
5285 && (DECL_COPY_CONSTRUCTOR_P (fn)
5286 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5289 arg = argarray[num_artificial_parms_for (fn)];
5291 /* Pull out the real argument, disregarding const-correctness. */
5293 while (CONVERT_EXPR_P (targ)
5294 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5295 targ = TREE_OPERAND (targ, 0);
5296 if (TREE_CODE (targ) == ADDR_EXPR)
5298 targ = TREE_OPERAND (targ, 0);
5299 if (!same_type_ignoring_top_level_qualifiers_p
5300 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5309 arg = cp_build_indirect_ref (arg, 0, complain);
5311 /* [class.copy]: the copy constructor is implicitly defined even if
5312 the implementation elided its use. */
5313 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5316 already_used = true;
5319 /* If we're creating a temp and we already have one, don't create a
5320 new one. If we're not creating a temp but we get one, use
5321 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5322 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5323 temp or an INIT_EXPR otherwise. */
5324 if (integer_zerop (TREE_VALUE (args)))
5326 if (TREE_CODE (arg) == TARGET_EXPR)
5328 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5329 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5331 else if (TREE_CODE (arg) == TARGET_EXPR
5332 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5333 && !move_fn_p (fn)))
5335 tree to = stabilize_reference
5336 (cp_build_indirect_ref (TREE_VALUE (args), 0, complain));
5338 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5342 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5344 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5346 tree to = stabilize_reference
5347 (cp_build_indirect_ref (argarray[0], 0, complain));
5348 tree type = TREE_TYPE (to);
5349 tree as_base = CLASSTYPE_AS_BASE (type);
5352 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5354 arg = cp_build_indirect_ref (arg, 0, complain);
5355 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5359 /* We must only copy the non-tail padding parts.
5360 Use __builtin_memcpy for the bitwise copy. */
5362 tree arg0, arg1, arg2, t;
5364 arg2 = TYPE_SIZE_UNIT (as_base);
5366 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5367 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5368 t = build_call_n (t, 3, arg0, arg1, arg2);
5370 t = convert (TREE_TYPE (arg0), t);
5371 val = cp_build_indirect_ref (t, 0, complain);
5380 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5383 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5386 gcc_assert (binfo && binfo != error_mark_node);
5388 /* Warn about deprecated virtual functions now, since we're about
5389 to throw away the decl. */
5390 if (TREE_DEPRECATED (fn))
5391 warn_deprecated_use (fn);
5393 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5394 if (TREE_SIDE_EFFECTS (argarray[0]))
5395 argarray[0] = save_expr (argarray[0]);
5396 t = build_pointer_type (TREE_TYPE (fn));
5397 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5398 fn = build_java_interface_fn_ref (fn, argarray[0]);
5400 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5404 fn = build_addr_func (fn);
5406 return build_cxx_call (fn, nargs, argarray);
5409 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5410 This function performs no overload resolution, conversion, or other
5411 high-level operations. */
5414 build_cxx_call (tree fn, int nargs, tree *argarray)
5418 fn = build_call_a (fn, nargs, argarray);
5420 /* If this call might throw an exception, note that fact. */
5421 fndecl = get_callee_fndecl (fn);
5422 if ((!fndecl || !TREE_NOTHROW (fndecl))
5423 && at_function_scope_p ()
5425 cp_function_chain->can_throw = 1;
5427 /* Check that arguments to builtin functions match the expectations. */
5429 && DECL_BUILT_IN (fndecl)
5430 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5431 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5432 return error_mark_node;
5434 /* Some built-in function calls will be evaluated at compile-time in
5436 fn = fold_if_not_in_template (fn);
5438 if (VOID_TYPE_P (TREE_TYPE (fn)))
5441 fn = require_complete_type (fn);
5442 if (fn == error_mark_node)
5443 return error_mark_node;
5445 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5446 fn = build_cplus_new (TREE_TYPE (fn), fn);
5447 return convert_from_reference (fn);
5450 static GTY(()) tree java_iface_lookup_fn;
5452 /* Make an expression which yields the address of the Java interface
5453 method FN. This is achieved by generating a call to libjava's
5454 _Jv_LookupInterfaceMethodIdx(). */
5457 build_java_interface_fn_ref (tree fn, tree instance)
5459 tree lookup_fn, method, idx;
5460 tree klass_ref, iface, iface_ref;
5463 if (!java_iface_lookup_fn)
5465 tree endlink = build_void_list_node ();
5466 tree t = tree_cons (NULL_TREE, ptr_type_node,
5467 tree_cons (NULL_TREE, ptr_type_node,
5468 tree_cons (NULL_TREE, java_int_type_node,
5470 java_iface_lookup_fn
5471 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5472 build_function_type (ptr_type_node, t),
5473 0, NOT_BUILT_IN, NULL, NULL_TREE);
5476 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5477 This is the first entry in the vtable. */
5478 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5479 tf_warning_or_error),
5482 /* Get the java.lang.Class pointer for the interface being called. */
5483 iface = DECL_CONTEXT (fn);
5484 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5485 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5486 || DECL_CONTEXT (iface_ref) != iface)
5488 error ("could not find class$ field in java interface type %qT",
5490 return error_mark_node;
5492 iface_ref = build_address (iface_ref);
5493 iface_ref = convert (build_pointer_type (iface), iface_ref);
5495 /* Determine the itable index of FN. */
5497 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5499 if (!DECL_VIRTUAL_P (method))
5505 idx = build_int_cst (NULL_TREE, i);
5507 lookup_fn = build1 (ADDR_EXPR,
5508 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5509 java_iface_lookup_fn);
5510 return build_call_nary (ptr_type_node, lookup_fn,
5511 3, klass_ref, iface_ref, idx);
5514 /* Returns the value to use for the in-charge parameter when making a
5515 call to a function with the indicated NAME.
5517 FIXME:Can't we find a neater way to do this mapping? */
5520 in_charge_arg_for_name (tree name)
5522 if (name == base_ctor_identifier
5523 || name == base_dtor_identifier)
5524 return integer_zero_node;
5525 else if (name == complete_ctor_identifier)
5526 return integer_one_node;
5527 else if (name == complete_dtor_identifier)
5528 return integer_two_node;
5529 else if (name == deleting_dtor_identifier)
5530 return integer_three_node;
5532 /* This function should only be called with one of the names listed
5538 /* Build a call to a constructor, destructor, or an assignment
5539 operator for INSTANCE, an expression with class type. NAME
5540 indicates the special member function to call; ARGS are the
5541 arguments. BINFO indicates the base of INSTANCE that is to be
5542 passed as the `this' parameter to the member function called.
5544 FLAGS are the LOOKUP_* flags to use when processing the call.
5546 If NAME indicates a complete object constructor, INSTANCE may be
5547 NULL_TREE. In this case, the caller will call build_cplus_new to
5548 store the newly constructed object into a VAR_DECL. */
5551 build_special_member_call (tree instance, tree name, tree args,
5552 tree binfo, int flags, tsubst_flags_t complain)
5555 /* The type of the subobject to be constructed or destroyed. */
5558 gcc_assert (name == complete_ctor_identifier
5559 || name == base_ctor_identifier
5560 || name == complete_dtor_identifier
5561 || name == base_dtor_identifier
5562 || name == deleting_dtor_identifier
5563 || name == ansi_assopname (NOP_EXPR));
5566 /* Resolve the name. */
5567 if (!complete_type_or_else (binfo, NULL_TREE))
5568 return error_mark_node;
5570 binfo = TYPE_BINFO (binfo);
5573 gcc_assert (binfo != NULL_TREE);
5575 class_type = BINFO_TYPE (binfo);
5577 /* Handle the special case where INSTANCE is NULL_TREE. */
5578 if (name == complete_ctor_identifier && !instance)
5580 instance = build_int_cst (build_pointer_type (class_type), 0);
5581 instance = build1 (INDIRECT_REF, class_type, instance);
5585 if (name == complete_dtor_identifier
5586 || name == base_dtor_identifier
5587 || name == deleting_dtor_identifier)
5588 gcc_assert (args == NULL_TREE);
5590 /* Convert to the base class, if necessary. */
5591 if (!same_type_ignoring_top_level_qualifiers_p
5592 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5594 if (name != ansi_assopname (NOP_EXPR))
5595 /* For constructors and destructors, either the base is
5596 non-virtual, or it is virtual but we are doing the
5597 conversion from a constructor or destructor for the
5598 complete object. In either case, we can convert
5600 instance = convert_to_base_statically (instance, binfo);
5602 /* However, for assignment operators, we must convert
5603 dynamically if the base is virtual. */
5604 instance = build_base_path (PLUS_EXPR, instance,
5605 binfo, /*nonnull=*/1);
5609 gcc_assert (instance != NULL_TREE);
5611 fns = lookup_fnfields (binfo, name, 1);
5613 /* When making a call to a constructor or destructor for a subobject
5614 that uses virtual base classes, pass down a pointer to a VTT for
5616 if ((name == base_ctor_identifier
5617 || name == base_dtor_identifier)
5618 && CLASSTYPE_VBASECLASSES (class_type))
5623 /* If the current function is a complete object constructor
5624 or destructor, then we fetch the VTT directly.
5625 Otherwise, we look it up using the VTT we were given. */
5626 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5627 vtt = decay_conversion (vtt);
5628 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5629 build2 (EQ_EXPR, boolean_type_node,
5630 current_in_charge_parm, integer_zero_node),
5633 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5634 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5635 BINFO_SUBVTT_INDEX (binfo));
5637 args = tree_cons (NULL_TREE, sub_vtt, args);
5640 return build_new_method_call (instance, fns, args,
5641 TYPE_BINFO (BINFO_TYPE (binfo)),
5646 /* Return the NAME, as a C string. The NAME indicates a function that
5647 is a member of TYPE. *FREE_P is set to true if the caller must
5648 free the memory returned.
5650 Rather than go through all of this, we should simply set the names
5651 of constructors and destructors appropriately, and dispense with
5652 ctor_identifier, dtor_identifier, etc. */
5655 name_as_c_string (tree name, tree type, bool *free_p)
5659 /* Assume that we will not allocate memory. */
5661 /* Constructors and destructors are special. */
5662 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5665 = CONST_CAST (char *, IDENTIFIER_POINTER (constructor_name (type)));
5666 /* For a destructor, add the '~'. */
5667 if (name == complete_dtor_identifier
5668 || name == base_dtor_identifier
5669 || name == deleting_dtor_identifier)
5671 pretty_name = concat ("~", pretty_name, NULL);
5672 /* Remember that we need to free the memory allocated. */
5676 else if (IDENTIFIER_TYPENAME_P (name))
5678 pretty_name = concat ("operator ",
5679 type_as_string (TREE_TYPE (name),
5680 TFF_PLAIN_IDENTIFIER),
5682 /* Remember that we need to free the memory allocated. */
5686 pretty_name = CONST_CAST (char *, IDENTIFIER_POINTER (name));
5691 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
5692 be set, upon return, to the function called. */
5695 build_new_method_call (tree instance, tree fns, tree args,
5696 tree conversion_path, int flags,
5697 tree *fn_p, tsubst_flags_t complain)
5699 struct z_candidate *candidates = 0, *cand;
5700 tree explicit_targs = NULL_TREE;
5701 tree basetype = NULL_TREE;
5704 tree mem_args = NULL_TREE, instance_ptr;
5710 int template_only = 0;
5717 gcc_assert (instance != NULL_TREE);
5719 /* We don't know what function we're going to call, yet. */
5723 if (error_operand_p (instance)
5724 || error_operand_p (fns)
5725 || args == error_mark_node)
5726 return error_mark_node;
5728 if (!BASELINK_P (fns))
5730 if (complain & tf_error)
5731 error ("call to non-function %qD", fns);
5732 return error_mark_node;
5735 orig_instance = instance;
5739 /* Dismantle the baselink to collect all the information we need. */
5740 if (!conversion_path)
5741 conversion_path = BASELINK_BINFO (fns);
5742 access_binfo = BASELINK_ACCESS_BINFO (fns);
5743 optype = BASELINK_OPTYPE (fns);
5744 fns = BASELINK_FUNCTIONS (fns);
5745 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5747 explicit_targs = TREE_OPERAND (fns, 1);
5748 fns = TREE_OPERAND (fns, 0);
5751 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5752 || TREE_CODE (fns) == TEMPLATE_DECL
5753 || TREE_CODE (fns) == OVERLOAD);
5754 fn = get_first_fn (fns);
5755 name = DECL_NAME (fn);
5757 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5758 gcc_assert (CLASS_TYPE_P (basetype));
5760 if (processing_template_decl)
5762 instance = build_non_dependent_expr (instance);
5763 args = build_non_dependent_args (orig_args);
5766 /* The USER_ARGS are the arguments we will display to users if an
5767 error occurs. The USER_ARGS should not include any
5768 compiler-generated arguments. The "this" pointer hasn't been
5769 added yet. However, we must remove the VTT pointer if this is a
5770 call to a base-class constructor or destructor. */
5772 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5774 /* Callers should explicitly indicate whether they want to construct
5775 the complete object or just the part without virtual bases. */
5776 gcc_assert (name != ctor_identifier);
5777 /* Similarly for destructors. */
5778 gcc_assert (name != dtor_identifier);
5779 /* Remove the VTT pointer, if present. */
5780 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5781 && CLASSTYPE_VBASECLASSES (basetype))
5782 user_args = TREE_CHAIN (user_args);
5785 /* Process the argument list. */
5786 args = resolve_args (args);
5787 if (args == error_mark_node)
5788 return error_mark_node;
5790 instance_ptr = build_this (instance);
5792 /* It's OK to call destructors and constructors on cv-qualified objects.
5793 Therefore, convert the INSTANCE_PTR to the unqualified type, if
5795 if (DECL_DESTRUCTOR_P (fn)
5796 || DECL_CONSTRUCTOR_P (fn))
5798 tree type = build_pointer_type (basetype);
5799 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5800 instance_ptr = build_nop (type, instance_ptr);
5802 if (DECL_DESTRUCTOR_P (fn))
5803 name = complete_dtor_identifier;
5805 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
5806 initializer, not T({ }). If the type doesn't have a list ctor,
5807 break apart the list into separate ctor args. */
5808 if (DECL_CONSTRUCTOR_P (fn) && args
5809 && BRACE_ENCLOSED_INITIALIZER_P (TREE_VALUE (args))
5810 && CONSTRUCTOR_IS_DIRECT_INIT (TREE_VALUE (args))
5811 && !TYPE_HAS_LIST_CTOR (basetype))
5813 gcc_assert (TREE_CHAIN (args) == NULL_TREE);
5814 args = ctor_to_list (TREE_VALUE (args));
5817 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5818 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5820 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5821 p = conversion_obstack_alloc (0);
5823 for (fn = fns; fn; fn = OVL_NEXT (fn))
5825 tree t = OVL_CURRENT (fn);
5828 /* We can end up here for copy-init of same or base class. */
5829 if ((flags & LOOKUP_ONLYCONVERTING)
5830 && DECL_NONCONVERTING_P (t))
5833 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5834 this_arglist = mem_args;
5836 this_arglist = args;
5838 if (TREE_CODE (t) == TEMPLATE_DECL)
5839 /* A member template. */
5840 add_template_candidate (&candidates, t,
5843 this_arglist, optype,
5848 else if (! template_only)
5849 add_function_candidate (&candidates, t,
5857 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5860 if (complain & tf_error)
5862 if (!COMPLETE_TYPE_P (basetype))
5863 cxx_incomplete_type_error (instance_ptr, basetype);
5869 pretty_name = name_as_c_string (name, basetype, &free_p);
5870 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5871 basetype, pretty_name, user_args,
5872 TREE_TYPE (TREE_TYPE (instance_ptr)));
5876 print_z_candidates (candidates);
5878 call = error_mark_node;
5882 cand = tourney (candidates);
5888 if (complain & tf_error)
5890 pretty_name = name_as_c_string (name, basetype, &free_p);
5891 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5893 print_z_candidates (candidates);
5897 call = error_mark_node;
5903 if (!(flags & LOOKUP_NONVIRTUAL)
5904 && DECL_PURE_VIRTUAL_P (fn)
5905 && instance == current_class_ref
5906 && (DECL_CONSTRUCTOR_P (current_function_decl)
5907 || DECL_DESTRUCTOR_P (current_function_decl))
5908 && (complain & tf_warning))
5909 /* This is not an error, it is runtime undefined
5911 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5912 "abstract virtual %q#D called from constructor"
5913 : "abstract virtual %q#D called from destructor"),
5916 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
5917 && is_dummy_object (instance_ptr))
5919 if (complain & tf_error)
5920 error ("cannot call member function %qD without object",
5922 call = error_mark_node;
5926 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
5927 && resolves_to_fixed_type_p (instance, 0))
5928 flags |= LOOKUP_NONVIRTUAL;
5929 /* Now we know what function is being called. */
5932 /* Build the actual CALL_EXPR. */
5933 call = build_over_call (cand, flags, complain);
5934 /* In an expression of the form `a->f()' where `f' turns
5935 out to be a static member function, `a' is
5936 none-the-less evaluated. */
5937 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
5938 && !is_dummy_object (instance_ptr)
5939 && TREE_SIDE_EFFECTS (instance_ptr))
5940 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5941 instance_ptr, call);
5942 else if (call != error_mark_node
5943 && DECL_DESTRUCTOR_P (cand->fn)
5944 && !VOID_TYPE_P (TREE_TYPE (call)))
5945 /* An explicit call of the form "x->~X()" has type
5946 "void". However, on platforms where destructors
5947 return "this" (i.e., those where
5948 targetm.cxx.cdtor_returns_this is true), such calls
5949 will appear to have a return value of pointer type
5950 to the low-level call machinery. We do not want to
5951 change the low-level machinery, since we want to be
5952 able to optimize "delete f()" on such platforms as
5953 "operator delete(~X(f()))" (rather than generating
5954 "t = f(), ~X(t), operator delete (t)"). */
5955 call = build_nop (void_type_node, call);
5960 if (processing_template_decl && call != error_mark_node)
5961 call = (build_min_non_dep_call_list
5963 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5966 /* Free all the conversions we allocated. */
5967 obstack_free (&conversion_obstack, p);
5972 /* Returns true iff standard conversion sequence ICS1 is a proper
5973 subsequence of ICS2. */
5976 is_subseq (conversion *ics1, conversion *ics2)
5978 /* We can assume that a conversion of the same code
5979 between the same types indicates a subsequence since we only get
5980 here if the types we are converting from are the same. */
5982 while (ics1->kind == ck_rvalue
5983 || ics1->kind == ck_lvalue)
5984 ics1 = ics1->u.next;
5988 while (ics2->kind == ck_rvalue
5989 || ics2->kind == ck_lvalue)
5990 ics2 = ics2->u.next;
5992 if (ics2->kind == ck_user
5993 || ics2->kind == ck_ambig
5994 || ics2->kind == ck_identity)
5995 /* At this point, ICS1 cannot be a proper subsequence of
5996 ICS2. We can get a USER_CONV when we are comparing the
5997 second standard conversion sequence of two user conversion
6001 ics2 = ics2->u.next;
6003 if (ics2->kind == ics1->kind
6004 && same_type_p (ics2->type, ics1->type)
6005 && same_type_p (ics2->u.next->type,
6006 ics1->u.next->type))
6011 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6012 be any _TYPE nodes. */
6015 is_properly_derived_from (tree derived, tree base)
6017 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6020 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6021 considers every class derived from itself. */
6022 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6023 && DERIVED_FROM_P (base, derived));
6026 /* We build the ICS for an implicit object parameter as a pointer
6027 conversion sequence. However, such a sequence should be compared
6028 as if it were a reference conversion sequence. If ICS is the
6029 implicit conversion sequence for an implicit object parameter,
6030 modify it accordingly. */
6033 maybe_handle_implicit_object (conversion **ics)
6037 /* [over.match.funcs]
6039 For non-static member functions, the type of the
6040 implicit object parameter is "reference to cv X"
6041 where X is the class of which the function is a
6042 member and cv is the cv-qualification on the member
6043 function declaration. */
6044 conversion *t = *ics;
6045 tree reference_type;
6047 /* The `this' parameter is a pointer to a class type. Make the
6048 implicit conversion talk about a reference to that same class
6050 reference_type = TREE_TYPE (t->type);
6051 reference_type = build_reference_type (reference_type);
6053 if (t->kind == ck_qual)
6055 if (t->kind == ck_ptr)
6057 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6058 t = direct_reference_binding (reference_type, t);
6060 t->rvaluedness_matches_p = 0;
6065 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6066 and return the initial reference binding conversion. Otherwise,
6067 leave *ICS unchanged and return NULL. */
6070 maybe_handle_ref_bind (conversion **ics)
6072 if ((*ics)->kind == ck_ref_bind)
6074 conversion *old_ics = *ics;
6075 *ics = old_ics->u.next;
6076 (*ics)->user_conv_p = old_ics->user_conv_p;
6077 (*ics)->bad_p = old_ics->bad_p;
6084 /* Compare two implicit conversion sequences according to the rules set out in
6085 [over.ics.rank]. Return values:
6087 1: ics1 is better than ics2
6088 -1: ics2 is better than ics1
6089 0: ics1 and ics2 are indistinguishable */
6092 compare_ics (conversion *ics1, conversion *ics2)
6098 tree deref_from_type1 = NULL_TREE;
6099 tree deref_from_type2 = NULL_TREE;
6100 tree deref_to_type1 = NULL_TREE;
6101 tree deref_to_type2 = NULL_TREE;
6102 conversion_rank rank1, rank2;
6104 /* REF_BINDING is nonzero if the result of the conversion sequence
6105 is a reference type. In that case REF_CONV is the reference
6106 binding conversion. */
6107 conversion *ref_conv1;
6108 conversion *ref_conv2;
6110 /* Handle implicit object parameters. */
6111 maybe_handle_implicit_object (&ics1);
6112 maybe_handle_implicit_object (&ics2);
6114 /* Handle reference parameters. */
6115 ref_conv1 = maybe_handle_ref_bind (&ics1);
6116 ref_conv2 = maybe_handle_ref_bind (&ics2);
6120 When comparing the basic forms of implicit conversion sequences (as
6121 defined in _over.best.ics_)
6123 --a standard conversion sequence (_over.ics.scs_) is a better
6124 conversion sequence than a user-defined conversion sequence
6125 or an ellipsis conversion sequence, and
6127 --a user-defined conversion sequence (_over.ics.user_) is a
6128 better conversion sequence than an ellipsis conversion sequence
6129 (_over.ics.ellipsis_). */
6130 rank1 = CONVERSION_RANK (ics1);
6131 rank2 = CONVERSION_RANK (ics2);
6135 else if (rank1 < rank2)
6138 if (rank1 == cr_bad)
6140 /* XXX Isn't this an extension? */
6141 /* Both ICS are bad. We try to make a decision based on what
6142 would have happened if they'd been good. */
6143 if (ics1->user_conv_p > ics2->user_conv_p
6144 || ics1->rank > ics2->rank)
6146 else if (ics1->user_conv_p < ics2->user_conv_p
6147 || ics1->rank < ics2->rank)
6150 /* We couldn't make up our minds; try to figure it out below. */
6153 if (ics1->ellipsis_p)
6154 /* Both conversions are ellipsis conversions. */
6157 /* User-defined conversion sequence U1 is a better conversion sequence
6158 than another user-defined conversion sequence U2 if they contain the
6159 same user-defined conversion operator or constructor and if the sec-
6160 ond standard conversion sequence of U1 is better than the second
6161 standard conversion sequence of U2. */
6163 if (ics1->user_conv_p)
6168 for (t1 = ics1; t1->kind != ck_user && t1->kind != ck_list; t1 = t1->u.next)
6169 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6171 for (t2 = ics2; t2->kind != ck_user && t2->kind != ck_list; t2 = t2->u.next)
6172 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6175 /* Conversion to std::initializer_list is better than other
6176 user-defined conversions. */
6177 if (t1->kind == ck_list
6178 || t2->kind == ck_list)
6180 if (t2->kind != ck_list)
6182 else if (t1->kind != ck_list)
6188 if (t1->cand->fn != t2->cand->fn)
6191 /* We can just fall through here, after setting up
6192 FROM_TYPE1 and FROM_TYPE2. */
6193 from_type1 = t1->type;
6194 from_type2 = t2->type;
6201 /* We're dealing with two standard conversion sequences.
6205 Standard conversion sequence S1 is a better conversion
6206 sequence than standard conversion sequence S2 if
6208 --S1 is a proper subsequence of S2 (comparing the conversion
6209 sequences in the canonical form defined by _over.ics.scs_,
6210 excluding any Lvalue Transformation; the identity
6211 conversion sequence is considered to be a subsequence of
6212 any non-identity conversion sequence */
6215 while (t1->kind != ck_identity)
6217 from_type1 = t1->type;
6220 while (t2->kind != ck_identity)
6222 from_type2 = t2->type;
6225 /* One sequence can only be a subsequence of the other if they start with
6226 the same type. They can start with different types when comparing the
6227 second standard conversion sequence in two user-defined conversion
6229 if (same_type_p (from_type1, from_type2))
6231 if (is_subseq (ics1, ics2))
6233 if (is_subseq (ics2, ics1))
6241 --the rank of S1 is better than the rank of S2 (by the rules
6244 Standard conversion sequences are ordered by their ranks: an Exact
6245 Match is a better conversion than a Promotion, which is a better
6246 conversion than a Conversion.
6248 Two conversion sequences with the same rank are indistinguishable
6249 unless one of the following rules applies:
6251 --A conversion that is not a conversion of a pointer, or pointer
6252 to member, to bool is better than another conversion that is such
6255 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6256 so that we do not have to check it explicitly. */
6257 if (ics1->rank < ics2->rank)
6259 else if (ics2->rank < ics1->rank)
6262 to_type1 = ics1->type;
6263 to_type2 = ics2->type;
6265 /* A conversion from scalar arithmetic type to complex is worse than a
6266 conversion between scalar arithmetic types. */
6267 if (same_type_p (from_type1, from_type2)
6268 && ARITHMETIC_TYPE_P (from_type1)
6269 && ARITHMETIC_TYPE_P (to_type1)
6270 && ARITHMETIC_TYPE_P (to_type2)
6271 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6272 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6274 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6280 if (TYPE_PTR_P (from_type1)
6281 && TYPE_PTR_P (from_type2)
6282 && TYPE_PTR_P (to_type1)
6283 && TYPE_PTR_P (to_type2))
6285 deref_from_type1 = TREE_TYPE (from_type1);
6286 deref_from_type2 = TREE_TYPE (from_type2);
6287 deref_to_type1 = TREE_TYPE (to_type1);
6288 deref_to_type2 = TREE_TYPE (to_type2);
6290 /* The rules for pointers to members A::* are just like the rules
6291 for pointers A*, except opposite: if B is derived from A then
6292 A::* converts to B::*, not vice versa. For that reason, we
6293 switch the from_ and to_ variables here. */
6294 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6295 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6296 || (TYPE_PTRMEMFUNC_P (from_type1)
6297 && TYPE_PTRMEMFUNC_P (from_type2)
6298 && TYPE_PTRMEMFUNC_P (to_type1)
6299 && TYPE_PTRMEMFUNC_P (to_type2)))
6301 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6302 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6303 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6304 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6307 if (deref_from_type1 != NULL_TREE
6308 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6309 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6311 /* This was one of the pointer or pointer-like conversions.
6315 --If class B is derived directly or indirectly from class A,
6316 conversion of B* to A* is better than conversion of B* to
6317 void*, and conversion of A* to void* is better than
6318 conversion of B* to void*. */
6319 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6320 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6322 if (is_properly_derived_from (deref_from_type1,
6325 else if (is_properly_derived_from (deref_from_type2,
6329 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6330 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6332 if (same_type_p (deref_from_type1, deref_from_type2))
6334 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6336 if (is_properly_derived_from (deref_from_type1,
6340 /* We know that DEREF_TO_TYPE1 is `void' here. */
6341 else if (is_properly_derived_from (deref_from_type1,
6346 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6347 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6351 --If class B is derived directly or indirectly from class A
6352 and class C is derived directly or indirectly from B,
6354 --conversion of C* to B* is better than conversion of C* to
6357 --conversion of B* to A* is better than conversion of C* to
6359 if (same_type_p (deref_from_type1, deref_from_type2))
6361 if (is_properly_derived_from (deref_to_type1,
6364 else if (is_properly_derived_from (deref_to_type2,
6368 else if (same_type_p (deref_to_type1, deref_to_type2))
6370 if (is_properly_derived_from (deref_from_type2,
6373 else if (is_properly_derived_from (deref_from_type1,
6379 else if (CLASS_TYPE_P (non_reference (from_type1))
6380 && same_type_p (from_type1, from_type2))
6382 tree from = non_reference (from_type1);
6386 --binding of an expression of type C to a reference of type
6387 B& is better than binding an expression of type C to a
6388 reference of type A&
6390 --conversion of C to B is better than conversion of C to A, */
6391 if (is_properly_derived_from (from, to_type1)
6392 && is_properly_derived_from (from, to_type2))
6394 if (is_properly_derived_from (to_type1, to_type2))
6396 else if (is_properly_derived_from (to_type2, to_type1))
6400 else if (CLASS_TYPE_P (non_reference (to_type1))
6401 && same_type_p (to_type1, to_type2))
6403 tree to = non_reference (to_type1);
6407 --binding of an expression of type B to a reference of type
6408 A& is better than binding an expression of type C to a
6409 reference of type A&,
6411 --conversion of B to A is better than conversion of C to A */
6412 if (is_properly_derived_from (from_type1, to)
6413 && is_properly_derived_from (from_type2, to))
6415 if (is_properly_derived_from (from_type2, from_type1))
6417 else if (is_properly_derived_from (from_type1, from_type2))
6424 --S1 and S2 differ only in their qualification conversion and yield
6425 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6426 qualification signature of type T1 is a proper subset of the cv-
6427 qualification signature of type T2 */
6428 if (ics1->kind == ck_qual
6429 && ics2->kind == ck_qual
6430 && same_type_p (from_type1, from_type2))
6432 int result = comp_cv_qual_signature (to_type1, to_type2);
6439 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6440 to an implicit object parameter, and either S1 binds an lvalue reference
6441 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6442 reference to an rvalue and S2 binds an lvalue reference
6443 (C++0x draft standard, 13.3.3.2)
6445 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6446 types to which the references refer are the same type except for
6447 top-level cv-qualifiers, and the type to which the reference
6448 initialized by S2 refers is more cv-qualified than the type to
6449 which the reference initialized by S1 refers */
6451 if (ref_conv1 && ref_conv2)
6453 if (!ref_conv1->this_p && !ref_conv2->this_p
6454 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6455 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6457 if (ref_conv1->rvaluedness_matches_p)
6459 if (ref_conv2->rvaluedness_matches_p)
6463 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6464 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6465 TREE_TYPE (ref_conv1->type));
6468 /* Neither conversion sequence is better than the other. */
6472 /* The source type for this standard conversion sequence. */
6475 source_type (conversion *t)
6477 for (;; t = t->u.next)
6479 if (t->kind == ck_user
6480 || t->kind == ck_ambig
6481 || t->kind == ck_identity)
6487 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6488 a pointer to LOSER and re-running joust to produce the warning if WINNER
6489 is actually used. */
6492 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6494 candidate_warning *cw = (candidate_warning *)
6495 conversion_obstack_alloc (sizeof (candidate_warning));
6497 cw->next = winner->warnings;
6498 winner->warnings = cw;
6501 /* Compare two candidates for overloading as described in
6502 [over.match.best]. Return values:
6504 1: cand1 is better than cand2
6505 -1: cand2 is better than cand1
6506 0: cand1 and cand2 are indistinguishable */
6509 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6512 int off1 = 0, off2 = 0;
6516 /* Candidates that involve bad conversions are always worse than those
6518 if (cand1->viable > cand2->viable)
6520 if (cand1->viable < cand2->viable)
6523 /* If we have two pseudo-candidates for conversions to the same type,
6524 or two candidates for the same function, arbitrarily pick one. */
6525 if (cand1->fn == cand2->fn
6526 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6529 /* a viable function F1
6530 is defined to be a better function than another viable function F2 if
6531 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6532 ICSi(F2), and then */
6534 /* for some argument j, ICSj(F1) is a better conversion sequence than
6537 /* For comparing static and non-static member functions, we ignore
6538 the implicit object parameter of the non-static function. The
6539 standard says to pretend that the static function has an object
6540 parm, but that won't work with operator overloading. */
6541 len = cand1->num_convs;
6542 if (len != cand2->num_convs)
6544 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6545 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6547 gcc_assert (static_1 != static_2);
6558 for (i = 0; i < len; ++i)
6560 conversion *t1 = cand1->convs[i + off1];
6561 conversion *t2 = cand2->convs[i + off2];
6562 int comp = compare_ics (t1, t2);
6567 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6568 == cr_std + cr_promotion)
6569 && t1->kind == ck_std
6570 && t2->kind == ck_std
6571 && TREE_CODE (t1->type) == INTEGER_TYPE
6572 && TREE_CODE (t2->type) == INTEGER_TYPE
6573 && (TYPE_PRECISION (t1->type)
6574 == TYPE_PRECISION (t2->type))
6575 && (TYPE_UNSIGNED (t1->u.next->type)
6576 || (TREE_CODE (t1->u.next->type)
6579 tree type = t1->u.next->type;
6581 struct z_candidate *w, *l;
6583 type1 = t1->type, type2 = t2->type,
6584 w = cand1, l = cand2;
6586 type1 = t2->type, type2 = t1->type,
6587 w = cand2, l = cand1;
6591 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6592 type, type1, type2);
6593 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6599 if (winner && comp != winner)
6608 /* warn about confusing overload resolution for user-defined conversions,
6609 either between a constructor and a conversion op, or between two
6611 if (winner && warn_conversion && cand1->second_conv
6612 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6613 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6615 struct z_candidate *w, *l;
6616 bool give_warning = false;
6619 w = cand1, l = cand2;
6621 w = cand2, l = cand1;
6623 /* We don't want to complain about `X::operator T1 ()'
6624 beating `X::operator T2 () const', when T2 is a no less
6625 cv-qualified version of T1. */
6626 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6627 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6629 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6630 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6632 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6637 if (!comp_ptr_ttypes (t, f))
6638 give_warning = true;
6641 give_warning = true;
6647 tree source = source_type (w->convs[0]);
6648 if (! DECL_CONSTRUCTOR_P (w->fn))
6649 source = TREE_TYPE (source);
6650 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
6651 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
6652 source, w->second_conv->type))
6654 inform (input_location, " because conversion sequence for the argument is better");
6665 F1 is a non-template function and F2 is a template function
6668 if (!cand1->template_decl && cand2->template_decl)
6670 else if (cand1->template_decl && !cand2->template_decl)
6674 F1 and F2 are template functions and the function template for F1 is
6675 more specialized than the template for F2 according to the partial
6678 if (cand1->template_decl && cand2->template_decl)
6680 winner = more_specialized_fn
6681 (TI_TEMPLATE (cand1->template_decl),
6682 TI_TEMPLATE (cand2->template_decl),
6683 /* [temp.func.order]: The presence of unused ellipsis and default
6684 arguments has no effect on the partial ordering of function
6685 templates. add_function_candidate() will not have
6686 counted the "this" argument for constructors. */
6687 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6693 the context is an initialization by user-defined conversion (see
6694 _dcl.init_ and _over.match.user_) and the standard conversion
6695 sequence from the return type of F1 to the destination type (i.e.,
6696 the type of the entity being initialized) is a better conversion
6697 sequence than the standard conversion sequence from the return type
6698 of F2 to the destination type. */
6700 if (cand1->second_conv)
6702 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6707 /* Check whether we can discard a builtin candidate, either because we
6708 have two identical ones or matching builtin and non-builtin candidates.
6710 (Pedantically in the latter case the builtin which matched the user
6711 function should not be added to the overload set, but we spot it here.
6714 ... the builtin candidates include ...
6715 - do not have the same parameter type list as any non-template
6716 non-member candidate. */
6718 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6719 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6721 for (i = 0; i < len; ++i)
6722 if (!same_type_p (cand1->convs[i]->type,
6723 cand2->convs[i]->type))
6725 if (i == cand1->num_convs)
6727 if (cand1->fn == cand2->fn)
6728 /* Two built-in candidates; arbitrarily pick one. */
6730 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6731 /* cand1 is built-in; prefer cand2. */
6734 /* cand2 is built-in; prefer cand1. */
6739 /* If the two functions are the same (this can happen with declarations
6740 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6741 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6742 && equal_functions (cand1->fn, cand2->fn))
6747 /* Extension: If the worst conversion for one candidate is worse than the
6748 worst conversion for the other, take the first. */
6751 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6752 struct z_candidate *w = 0, *l = 0;
6754 for (i = 0; i < len; ++i)
6756 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6757 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6758 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6759 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6762 winner = 1, w = cand1, l = cand2;
6764 winner = -1, w = cand2, l = cand1;
6770 "ISO C++ says that these are ambiguous, even "
6771 "though the worst conversion for the first is better than "
6772 "the worst conversion for the second:");
6773 print_z_candidate (_("candidate 1:"), w);
6774 print_z_candidate (_("candidate 2:"), l);
6782 gcc_assert (!winner);
6786 /* Given a list of candidates for overloading, find the best one, if any.
6787 This algorithm has a worst case of O(2n) (winner is last), and a best
6788 case of O(n/2) (totally ambiguous); much better than a sorting
6791 static struct z_candidate *
6792 tourney (struct z_candidate *candidates)
6794 struct z_candidate *champ = candidates, *challenger;
6796 int champ_compared_to_predecessor = 0;
6798 /* Walk through the list once, comparing each current champ to the next
6799 candidate, knocking out a candidate or two with each comparison. */
6801 for (challenger = champ->next; challenger; )
6803 fate = joust (champ, challenger, 0);
6805 challenger = challenger->next;
6810 champ = challenger->next;
6813 champ_compared_to_predecessor = 0;
6818 champ_compared_to_predecessor = 1;
6821 challenger = champ->next;
6825 /* Make sure the champ is better than all the candidates it hasn't yet
6826 been compared to. */
6828 for (challenger = candidates;
6830 && !(champ_compared_to_predecessor && challenger->next == champ);
6831 challenger = challenger->next)
6833 fate = joust (champ, challenger, 0);
6841 /* Returns nonzero if things of type FROM can be converted to TO. */
6844 can_convert (tree to, tree from)
6846 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6849 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6852 can_convert_arg (tree to, tree from, tree arg, int flags)
6858 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6859 p = conversion_obstack_alloc (0);
6861 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6863 ok_p = (t && !t->bad_p);
6865 /* Free all the conversions we allocated. */
6866 obstack_free (&conversion_obstack, p);
6871 /* Like can_convert_arg, but allows dubious conversions as well. */
6874 can_convert_arg_bad (tree to, tree from, tree arg)
6879 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6880 p = conversion_obstack_alloc (0);
6881 /* Try to perform the conversion. */
6882 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6884 /* Free all the conversions we allocated. */
6885 obstack_free (&conversion_obstack, p);
6890 /* Convert EXPR to TYPE. Return the converted expression.
6892 Note that we allow bad conversions here because by the time we get to
6893 this point we are committed to doing the conversion. If we end up
6894 doing a bad conversion, convert_like will complain. */
6897 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
6902 if (error_operand_p (expr))
6903 return error_mark_node;
6905 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6906 p = conversion_obstack_alloc (0);
6908 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6913 if (complain & tf_error)
6914 error ("could not convert %qE to %qT", expr, type);
6915 expr = error_mark_node;
6917 else if (processing_template_decl)
6919 /* In a template, we are only concerned about determining the
6920 type of non-dependent expressions, so we do not have to
6921 perform the actual conversion. */
6922 if (TREE_TYPE (expr) != type)
6923 expr = build_nop (type, expr);
6926 expr = convert_like (conv, expr, complain);
6928 /* Free all the conversions we allocated. */
6929 obstack_free (&conversion_obstack, p);
6934 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6935 permitted. If the conversion is valid, the converted expression is
6936 returned. Otherwise, NULL_TREE is returned, except in the case
6937 that TYPE is a class type; in that case, an error is issued. If
6938 C_CAST_P is true, then this direction initialization is taking
6939 place as part of a static_cast being attempted as part of a C-style
6943 perform_direct_initialization_if_possible (tree type,
6946 tsubst_flags_t complain)
6951 if (type == error_mark_node || error_operand_p (expr))
6952 return error_mark_node;
6955 If the destination type is a (possibly cv-qualified) class type:
6957 -- If the initialization is direct-initialization ...,
6958 constructors are considered. ... If no constructor applies, or
6959 the overload resolution is ambiguous, the initialization is
6961 if (CLASS_TYPE_P (type))
6963 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6964 build_tree_list (NULL_TREE, expr),
6965 type, LOOKUP_NORMAL, complain);
6966 return build_cplus_new (type, expr);
6969 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6970 p = conversion_obstack_alloc (0);
6972 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6975 if (!conv || conv->bad_p)
6978 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6979 /*issue_conversion_warnings=*/false,
6981 tf_warning_or_error);
6983 /* Free all the conversions we allocated. */
6984 obstack_free (&conversion_obstack, p);
6989 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6990 is being bound to a temporary. Create and return a new VAR_DECL
6991 with the indicated TYPE; this variable will store the value to
6992 which the reference is bound. */
6995 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6999 /* Create the variable. */
7000 var = create_temporary_var (type);
7002 /* Register the variable. */
7003 if (TREE_STATIC (decl))
7005 /* Namespace-scope or local static; give it a mangled name. */
7008 TREE_STATIC (var) = 1;
7009 name = mangle_ref_init_variable (decl);
7010 DECL_NAME (var) = name;
7011 SET_DECL_ASSEMBLER_NAME (var, name);
7012 var = pushdecl_top_level (var);
7015 /* Create a new cleanup level if necessary. */
7016 maybe_push_cleanup_level (type);
7021 /* EXPR is the initializer for a variable DECL of reference or
7022 std::initializer_list type. Create, push and return a new VAR_DECL
7023 for the initializer so that it will live as long as DECL. Any
7024 cleanup for the new variable is returned through CLEANUP, and the
7025 code to initialize the new variable is returned through INITP. */
7028 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7034 /* Create the temporary variable. */
7035 type = TREE_TYPE (expr);
7036 var = make_temporary_var_for_ref_to_temp (decl, type);
7037 layout_decl (var, 0);
7038 /* If the rvalue is the result of a function call it will be
7039 a TARGET_EXPR. If it is some other construct (such as a
7040 member access expression where the underlying object is
7041 itself the result of a function call), turn it into a
7042 TARGET_EXPR here. It is important that EXPR be a
7043 TARGET_EXPR below since otherwise the INIT_EXPR will
7044 attempt to make a bitwise copy of EXPR to initialize
7046 if (TREE_CODE (expr) != TARGET_EXPR)
7047 expr = get_target_expr (expr);
7048 /* Create the INIT_EXPR that will initialize the temporary
7050 init = build2 (INIT_EXPR, type, var, expr);
7051 if (at_function_scope_p ())
7053 add_decl_expr (var);
7055 if (TREE_STATIC (var))
7056 init = add_stmt_to_compound (init, register_dtor_fn (var));
7058 *cleanup = cxx_maybe_build_cleanup (var);
7060 /* We must be careful to destroy the temporary only
7061 after its initialization has taken place. If the
7062 initialization throws an exception, then the
7063 destructor should not be run. We cannot simply
7064 transform INIT into something like:
7066 (INIT, ({ CLEANUP_STMT; }))
7068 because emit_local_var always treats the
7069 initializer as a full-expression. Thus, the
7070 destructor would run too early; it would run at the
7071 end of initializing the reference variable, rather
7072 than at the end of the block enclosing the
7075 The solution is to pass back a cleanup expression
7076 which the caller is responsible for attaching to
7077 the statement tree. */
7081 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7082 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7083 static_aggregates = tree_cons (NULL_TREE, var,
7091 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7092 initializing a variable of that TYPE. If DECL is non-NULL, it is
7093 the VAR_DECL being initialized with the EXPR. (In that case, the
7094 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7095 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7096 return, if *CLEANUP is no longer NULL, it will be an expression
7097 that should be pushed as a cleanup after the returned expression
7098 is used to initialize DECL.
7100 Return the converted expression. */
7103 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7108 if (type == error_mark_node || error_operand_p (expr))
7109 return error_mark_node;
7111 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7112 p = conversion_obstack_alloc (0);
7114 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7116 if (!conv || conv->bad_p)
7118 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7119 && !real_lvalue_p (expr))
7120 error ("invalid initialization of non-const reference of "
7121 "type %qT from a temporary of type %qT",
7122 type, TREE_TYPE (expr));
7124 error ("invalid initialization of reference of type "
7125 "%qT from expression of type %qT", type,
7127 return error_mark_node;
7130 /* If DECL is non-NULL, then this special rule applies:
7134 The temporary to which the reference is bound or the temporary
7135 that is the complete object to which the reference is bound
7136 persists for the lifetime of the reference.
7138 The temporaries created during the evaluation of the expression
7139 initializing the reference, except the temporary to which the
7140 reference is bound, are destroyed at the end of the
7141 full-expression in which they are created.
7143 In that case, we store the converted expression into a new
7144 VAR_DECL in a new scope.
7146 However, we want to be careful not to create temporaries when
7147 they are not required. For example, given:
7150 struct D : public B {};
7154 there is no need to copy the return value from "f"; we can just
7155 extend its lifetime. Similarly, given:
7158 struct T { operator S(); };
7162 we can extend the lifetime of the return value of the conversion
7164 gcc_assert (conv->kind == ck_ref_bind);
7168 tree base_conv_type;
7170 /* Skip over the REF_BIND. */
7171 conv = conv->u.next;
7172 /* If the next conversion is a BASE_CONV, skip that too -- but
7173 remember that the conversion was required. */
7174 if (conv->kind == ck_base)
7176 base_conv_type = conv->type;
7177 conv = conv->u.next;
7180 base_conv_type = NULL_TREE;
7181 /* Perform the remainder of the conversion. */
7182 expr = convert_like_real (conv, expr,
7183 /*fn=*/NULL_TREE, /*argnum=*/0,
7185 /*issue_conversion_warnings=*/true,
7187 tf_warning_or_error);
7188 if (error_operand_p (expr))
7189 expr = error_mark_node;
7192 if (!real_lvalue_p (expr))
7195 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7196 /* Use its address to initialize the reference variable. */
7197 expr = build_address (var);
7199 expr = convert_to_base (expr,
7200 build_pointer_type (base_conv_type),
7201 /*check_access=*/true,
7203 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7206 /* Take the address of EXPR. */
7207 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7208 /* If a BASE_CONV was required, perform it now. */
7210 expr = (perform_implicit_conversion
7211 (build_pointer_type (base_conv_type), expr,
7212 tf_warning_or_error));
7213 expr = build_nop (type, expr);
7217 /* Perform the conversion. */
7218 expr = convert_like (conv, expr, tf_warning_or_error);
7220 /* Free all the conversions we allocated. */
7221 obstack_free (&conversion_obstack, p);
7226 /* Returns true iff TYPE is some variant of std::initializer_list. */
7229 is_std_init_list (tree type)
7231 return (CLASS_TYPE_P (type)
7232 && CP_TYPE_CONTEXT (type) == std_node
7233 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7236 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7237 will accept an argument list of a single std::initializer_list<T>. */
7240 is_list_ctor (tree decl)
7242 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7245 if (!args || args == void_list_node)
7248 arg = non_reference (TREE_VALUE (args));
7249 if (!is_std_init_list (arg))
7252 args = TREE_CHAIN (args);
7254 if (args && args != void_list_node && !TREE_PURPOSE (args))
7255 /* There are more non-defaulted parms. */
7261 #include "gt-cp-call.h"