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 typedef void (*diagnostic_fn_t) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
205 static tree build_temp (tree, tree, int, diagnostic_fn_t *);
207 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
208 NAME can take many forms... */
211 check_dtor_name (tree basetype, tree name)
213 /* Just accept something we've already complained about. */
214 if (name == error_mark_node)
217 if (TREE_CODE (name) == TYPE_DECL)
218 name = TREE_TYPE (name);
219 else if (TYPE_P (name))
221 else if (TREE_CODE (name) == IDENTIFIER_NODE)
223 if ((MAYBE_CLASS_TYPE_P (basetype)
224 && name == constructor_name (basetype))
225 || (TREE_CODE (basetype) == ENUMERAL_TYPE
226 && name == TYPE_IDENTIFIER (basetype)))
229 name = get_type_value (name);
235 template <class T> struct S { ~S(); };
239 NAME will be a class template. */
240 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
246 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
249 /* We want the address of a function or method. We avoid creating a
250 pointer-to-member function. */
253 build_addr_func (tree function)
255 tree type = TREE_TYPE (function);
257 /* We have to do these by hand to avoid real pointer to member
259 if (TREE_CODE (type) == METHOD_TYPE)
261 if (TREE_CODE (function) == OFFSET_REF)
263 tree object = build_address (TREE_OPERAND (function, 0));
264 return get_member_function_from_ptrfunc (&object,
265 TREE_OPERAND (function, 1));
267 function = build_address (function);
270 function = decay_conversion (function);
275 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
276 POINTER_TYPE to those. Note, pointer to member function types
277 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
278 two variants. build_call_a is the primitive taking an array of
279 arguments, while build_call_n is a wrapper that handles varargs. */
282 build_call_n (tree function, int n, ...)
285 return build_call_a (function, 0, NULL);
288 tree *argarray = (tree *) alloca (n * sizeof (tree));
293 for (i = 0; i < n; i++)
294 argarray[i] = va_arg (ap, tree);
296 return build_call_a (function, n, argarray);
301 build_call_a (tree function, int n, tree *argarray)
303 int is_constructor = 0;
310 function = build_addr_func (function);
312 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
313 fntype = TREE_TYPE (TREE_TYPE (function));
314 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
315 || TREE_CODE (fntype) == METHOD_TYPE);
316 result_type = TREE_TYPE (fntype);
318 if (TREE_CODE (function) == ADDR_EXPR
319 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
321 decl = TREE_OPERAND (function, 0);
322 if (!TREE_USED (decl))
324 /* We invoke build_call directly for several library
325 functions. These may have been declared normally if
326 we're building libgcc, so we can't just check
328 gcc_assert (DECL_ARTIFICIAL (decl)
329 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
337 /* We check both the decl and the type; a function may be known not to
338 throw without being declared throw(). */
339 nothrow = ((decl && TREE_NOTHROW (decl))
340 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
342 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
343 current_function_returns_abnormally = 1;
345 if (decl && TREE_DEPRECATED (decl))
346 warn_deprecated_use (decl);
347 require_complete_eh_spec_types (fntype, decl);
349 if (decl && DECL_CONSTRUCTOR_P (decl))
352 /* Don't pass empty class objects by value. This is useful
353 for tags in STL, which are used to control overload resolution.
354 We don't need to handle other cases of copying empty classes. */
355 if (! decl || ! DECL_BUILT_IN (decl))
356 for (i = 0; i < n; i++)
357 if (is_empty_class (TREE_TYPE (argarray[i]))
358 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
360 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
361 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
365 function = build_call_array (result_type, function, n, argarray);
366 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
367 TREE_NOTHROW (function) = nothrow;
372 /* Build something of the form ptr->method (args)
373 or object.method (args). This can also build
374 calls to constructors, and find friends.
376 Member functions always take their class variable
379 INSTANCE is a class instance.
381 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
383 PARMS help to figure out what that NAME really refers to.
385 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
386 down to the real instance type to use for access checking. We need this
387 information to get protected accesses correct.
389 FLAGS is the logical disjunction of zero or more LOOKUP_
390 flags. See cp-tree.h for more info.
392 If this is all OK, calls build_function_call with the resolved
395 This function must also handle being called to perform
396 initialization, promotion/coercion of arguments, and
397 instantiation of default parameters.
399 Note that NAME may refer to an instance variable name. If
400 `operator()()' is defined for the type of that field, then we return
403 /* New overloading code. */
405 typedef struct z_candidate z_candidate;
407 typedef struct candidate_warning candidate_warning;
408 struct candidate_warning {
410 candidate_warning *next;
414 /* The FUNCTION_DECL that will be called if this candidate is
415 selected by overload resolution. */
417 /* The arguments to use when calling this function. */
419 /* The implicit conversion sequences for each of the arguments to
422 /* The number of implicit conversion sequences. */
424 /* If FN is a user-defined conversion, the standard conversion
425 sequence from the type returned by FN to the desired destination
427 conversion *second_conv;
429 /* If FN is a member function, the binfo indicating the path used to
430 qualify the name of FN at the call site. This path is used to
431 determine whether or not FN is accessible if it is selected by
432 overload resolution. The DECL_CONTEXT of FN will always be a
433 (possibly improper) base of this binfo. */
435 /* If FN is a non-static member function, the binfo indicating the
436 subobject to which the `this' pointer should be converted if FN
437 is selected by overload resolution. The type pointed to the by
438 the `this' pointer must correspond to the most derived class
439 indicated by the CONVERSION_PATH. */
440 tree conversion_path;
442 candidate_warning *warnings;
446 /* Returns true iff T is a null pointer constant in the sense of
450 null_ptr_cst_p (tree t)
454 A null pointer constant is an integral constant expression
455 (_expr.const_) rvalue of integer type that evaluates to zero. */
456 t = integral_constant_value (t);
459 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
462 if (!TREE_OVERFLOW (t))
468 /* Returns nonzero if PARMLIST consists of only default parms and/or
472 sufficient_parms_p (const_tree parmlist)
474 for (; parmlist && parmlist != void_list_node;
475 parmlist = TREE_CHAIN (parmlist))
476 if (!TREE_PURPOSE (parmlist))
481 /* Allocate N bytes of memory from the conversion obstack. The memory
482 is zeroed before being returned. */
485 conversion_obstack_alloc (size_t n)
488 if (!conversion_obstack_initialized)
490 gcc_obstack_init (&conversion_obstack);
491 conversion_obstack_initialized = true;
493 p = obstack_alloc (&conversion_obstack, n);
498 /* Dynamically allocate a conversion. */
501 alloc_conversion (conversion_kind kind)
504 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
509 #ifdef ENABLE_CHECKING
511 /* Make sure that all memory on the conversion obstack has been
515 validate_conversion_obstack (void)
517 if (conversion_obstack_initialized)
518 gcc_assert ((obstack_next_free (&conversion_obstack)
519 == obstack_base (&conversion_obstack)));
522 #endif /* ENABLE_CHECKING */
524 /* Dynamically allocate an array of N conversions. */
527 alloc_conversions (size_t n)
529 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
533 build_conv (conversion_kind code, tree type, conversion *from)
536 conversion_rank rank = CONVERSION_RANK (from);
538 /* Note that the caller is responsible for filling in t->cand for
539 user-defined conversions. */
540 t = alloc_conversion (code);
563 t->user_conv_p = (code == ck_user || from->user_conv_p);
564 t->bad_p = from->bad_p;
569 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
570 specialization of std::initializer_list<T>, if such a conversion is
574 build_list_conv (tree type, tree ctor, int flags)
576 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
577 unsigned len = CONSTRUCTOR_NELTS (ctor);
578 conversion **subconvs = alloc_conversions (len);
583 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
586 = implicit_conversion (elttype, TREE_TYPE (val), val,
594 t = alloc_conversion (ck_list);
596 t->u.list = subconvs;
599 for (i = 0; i < len; ++i)
601 conversion *sub = subconvs[i];
602 if (sub->rank > t->rank)
604 if (sub->user_conv_p)
605 t->user_conv_p = true;
613 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
614 aggregate class, if such a conversion is possible. */
617 build_aggr_conv (tree type, tree ctor, int flags)
619 unsigned HOST_WIDE_INT i = 0;
621 tree field = TYPE_FIELDS (type);
623 for (; field; field = TREE_CHAIN (field))
625 if (TREE_CODE (field) != FIELD_DECL)
627 if (i < CONSTRUCTOR_NELTS (ctor))
629 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
630 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
634 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
638 c = alloc_conversion (ck_aggr);
641 c->user_conv_p = true;
646 /* Build a representation of the identity conversion from EXPR to
647 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
650 build_identity_conv (tree type, tree expr)
654 c = alloc_conversion (ck_identity);
661 /* Converting from EXPR to TYPE was ambiguous in the sense that there
662 were multiple user-defined conversions to accomplish the job.
663 Build a conversion that indicates that ambiguity. */
666 build_ambiguous_conv (tree type, tree expr)
670 c = alloc_conversion (ck_ambig);
678 strip_top_quals (tree t)
680 if (TREE_CODE (t) == ARRAY_TYPE)
682 return cp_build_qualified_type (t, 0);
685 /* Returns the standard conversion path (see [conv]) from type FROM to type
686 TO, if any. For proper handling of null pointer constants, you must
687 also pass the expression EXPR to convert from. If C_CAST_P is true,
688 this conversion is coming from a C-style cast. */
691 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
694 enum tree_code fcode, tcode;
696 bool fromref = false;
698 to = non_reference (to);
699 if (TREE_CODE (from) == REFERENCE_TYPE)
702 from = TREE_TYPE (from);
704 to = strip_top_quals (to);
705 from = strip_top_quals (from);
707 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
708 && expr && type_unknown_p (expr))
710 expr = instantiate_type (to, expr, tf_conv);
711 if (expr == error_mark_node)
713 from = TREE_TYPE (expr);
716 fcode = TREE_CODE (from);
717 tcode = TREE_CODE (to);
719 conv = build_identity_conv (from, expr);
720 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
722 from = type_decays_to (from);
723 fcode = TREE_CODE (from);
724 conv = build_conv (ck_lvalue, from, conv);
726 else if (fromref || (expr && lvalue_p (expr)))
731 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
734 from = strip_top_quals (bitfield_type);
735 fcode = TREE_CODE (from);
738 conv = build_conv (ck_rvalue, from, conv);
741 /* Allow conversion between `__complex__' data types. */
742 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
744 /* The standard conversion sequence to convert FROM to TO is
745 the standard conversion sequence to perform componentwise
747 conversion *part_conv = standard_conversion
748 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
752 conv = build_conv (part_conv->kind, to, conv);
753 conv->rank = part_conv->rank;
761 if (same_type_p (from, to))
764 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
765 && expr && null_ptr_cst_p (expr))
766 conv = build_conv (ck_std, to, conv);
767 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
768 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
770 /* For backwards brain damage compatibility, allow interconversion of
771 pointers and integers with a pedwarn. */
772 conv = build_conv (ck_std, to, conv);
775 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
777 /* For backwards brain damage compatibility, allow interconversion of
778 enums and integers with a pedwarn. */
779 conv = build_conv (ck_std, to, conv);
782 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
783 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
788 if (tcode == POINTER_TYPE
789 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
792 else if (VOID_TYPE_P (TREE_TYPE (to))
793 && !TYPE_PTRMEM_P (from)
794 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
796 from = build_pointer_type
797 (cp_build_qualified_type (void_type_node,
798 cp_type_quals (TREE_TYPE (from))));
799 conv = build_conv (ck_ptr, from, conv);
801 else if (TYPE_PTRMEM_P (from))
803 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
804 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
806 if (DERIVED_FROM_P (fbase, tbase)
807 && (same_type_ignoring_top_level_qualifiers_p
808 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
809 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
811 from = build_ptrmem_type (tbase,
812 TYPE_PTRMEM_POINTED_TO_TYPE (from));
813 conv = build_conv (ck_pmem, from, conv);
815 else if (!same_type_p (fbase, tbase))
818 else if (MAYBE_CLASS_TYPE_P (TREE_TYPE (from))
819 && MAYBE_CLASS_TYPE_P (TREE_TYPE (to))
822 An rvalue of type "pointer to cv D," where D is a
823 class type, can be converted to an rvalue of type
824 "pointer to cv B," where B is a base class (clause
825 _class.derived_) of D. If B is an inaccessible
826 (clause _class.access_) or ambiguous
827 (_class.member.lookup_) base class of D, a program
828 that necessitates this conversion is ill-formed.
829 Therefore, we use DERIVED_FROM_P, and do not check
830 access or uniqueness. */
831 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
834 cp_build_qualified_type (TREE_TYPE (to),
835 cp_type_quals (TREE_TYPE (from)));
836 from = build_pointer_type (from);
837 conv = build_conv (ck_ptr, from, conv);
841 if (tcode == POINTER_TYPE)
843 to_pointee = TREE_TYPE (to);
844 from_pointee = TREE_TYPE (from);
848 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
849 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
852 if (same_type_p (from, to))
854 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
855 /* In a C-style cast, we ignore CV-qualification because we
856 are allowed to perform a static_cast followed by a
858 conv = build_conv (ck_qual, to, conv);
859 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
860 conv = build_conv (ck_qual, to, conv);
861 else if (expr && string_conv_p (to, expr, 0))
862 /* converting from string constant to char *. */
863 conv = build_conv (ck_qual, to, conv);
864 else if (ptr_reasonably_similar (to_pointee, from_pointee))
866 conv = build_conv (ck_ptr, to, conv);
874 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
876 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
877 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
878 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
879 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
881 if (!DERIVED_FROM_P (fbase, tbase)
882 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
883 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
884 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
885 || cp_type_quals (fbase) != cp_type_quals (tbase))
888 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
889 from = build_method_type_directly (from,
891 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
892 from = build_ptrmemfunc_type (build_pointer_type (from));
893 conv = build_conv (ck_pmem, from, conv);
896 else if (tcode == BOOLEAN_TYPE)
900 An rvalue of arithmetic, enumeration, pointer, or pointer to
901 member type can be converted to an rvalue of type bool. */
902 if (ARITHMETIC_TYPE_P (from)
903 || fcode == ENUMERAL_TYPE
904 || fcode == POINTER_TYPE
905 || TYPE_PTR_TO_MEMBER_P (from))
907 conv = build_conv (ck_std, to, conv);
908 if (fcode == POINTER_TYPE
909 || TYPE_PTRMEM_P (from)
910 || (TYPE_PTRMEMFUNC_P (from)
911 && conv->rank < cr_pbool))
912 conv->rank = cr_pbool;
918 /* We don't check for ENUMERAL_TYPE here because there are no standard
919 conversions to enum type. */
920 /* As an extension, allow conversion to complex type. */
921 else if (ARITHMETIC_TYPE_P (to))
923 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
925 conv = build_conv (ck_std, to, conv);
927 /* Give this a better rank if it's a promotion. */
928 if (same_type_p (to, type_promotes_to (from))
929 && conv->u.next->rank <= cr_promotion)
930 conv->rank = cr_promotion;
932 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
933 && vector_types_convertible_p (from, to, false))
934 return build_conv (ck_std, to, conv);
935 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
936 && is_properly_derived_from (from, to))
938 if (conv->kind == ck_rvalue)
940 conv = build_conv (ck_base, to, conv);
941 /* The derived-to-base conversion indicates the initialization
942 of a parameter with base type from an object of a derived
943 type. A temporary object is created to hold the result of
944 the conversion unless we're binding directly to a reference. */
945 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
950 if (flags & LOOKUP_NO_NARROWING)
951 conv->check_narrowing = true;
956 /* Returns nonzero if T1 is reference-related to T2. */
959 reference_related_p (tree t1, tree t2)
961 t1 = TYPE_MAIN_VARIANT (t1);
962 t2 = TYPE_MAIN_VARIANT (t2);
966 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
967 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
969 return (same_type_p (t1, t2)
970 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
971 && DERIVED_FROM_P (t1, t2)));
974 /* Returns nonzero if T1 is reference-compatible with T2. */
977 reference_compatible_p (tree t1, tree t2)
981 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
982 reference-related to T2 and cv1 is the same cv-qualification as,
983 or greater cv-qualification than, cv2. */
984 return (reference_related_p (t1, t2)
985 && at_least_as_qualified_p (t1, t2));
988 /* Determine whether or not the EXPR (of class type S) can be
989 converted to T as in [over.match.ref]. */
992 convert_class_to_reference (tree reference_type, tree s, tree expr)
998 struct z_candidate *candidates;
999 struct z_candidate *cand;
1002 conversions = lookup_conversions (s);
1008 Assuming that "cv1 T" is the underlying type of the reference
1009 being initialized, and "cv S" is the type of the initializer
1010 expression, with S a class type, the candidate functions are
1011 selected as follows:
1013 --The conversion functions of S and its base classes are
1014 considered. Those that are not hidden within S and yield type
1015 "reference to cv2 T2", where "cv1 T" is reference-compatible
1016 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1018 The argument list has one argument, which is the initializer
1023 /* Conceptually, we should take the address of EXPR and put it in
1024 the argument list. Unfortunately, however, that can result in
1025 error messages, which we should not issue now because we are just
1026 trying to find a conversion operator. Therefore, we use NULL,
1027 cast to the appropriate type. */
1028 arglist = build_int_cst (build_pointer_type (s), 0);
1029 arglist = build_tree_list (NULL_TREE, arglist);
1031 t = TREE_TYPE (reference_type);
1035 tree fns = TREE_VALUE (conversions);
1037 for (; fns; fns = OVL_NEXT (fns))
1039 tree f = OVL_CURRENT (fns);
1040 tree t2 = TREE_TYPE (TREE_TYPE (f));
1044 /* If this is a template function, try to get an exact
1046 if (TREE_CODE (f) == TEMPLATE_DECL)
1048 cand = add_template_candidate (&candidates,
1054 TREE_PURPOSE (conversions),
1060 /* Now, see if the conversion function really returns
1061 an lvalue of the appropriate type. From the
1062 point of view of unification, simply returning an
1063 rvalue of the right type is good enough. */
1065 t2 = TREE_TYPE (TREE_TYPE (f));
1066 if (TREE_CODE (t2) != REFERENCE_TYPE
1067 || !reference_compatible_p (t, TREE_TYPE (t2)))
1069 candidates = candidates->next;
1074 else if (TREE_CODE (t2) == REFERENCE_TYPE
1075 && reference_compatible_p (t, TREE_TYPE (t2)))
1076 cand = add_function_candidate (&candidates, f, s, arglist,
1078 TREE_PURPOSE (conversions),
1083 conversion *identity_conv;
1084 /* Build a standard conversion sequence indicating the
1085 binding from the reference type returned by the
1086 function to the desired REFERENCE_TYPE. */
1088 = build_identity_conv (TREE_TYPE (TREE_TYPE
1089 (TREE_TYPE (cand->fn))),
1092 = (direct_reference_binding
1093 (reference_type, identity_conv));
1094 cand->second_conv->rvaluedness_matches_p
1095 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1096 == TYPE_REF_IS_RVALUE (reference_type);
1097 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1100 conversions = TREE_CHAIN (conversions);
1103 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1104 /* If none of the conversion functions worked out, let our caller
1109 cand = tourney (candidates);
1113 /* Now that we know that this is the function we're going to use fix
1114 the dummy first argument. */
1115 cand->args = tree_cons (NULL_TREE,
1117 TREE_CHAIN (cand->args));
1119 /* Build a user-defined conversion sequence representing the
1121 conv = build_conv (ck_user,
1122 TREE_TYPE (TREE_TYPE (cand->fn)),
1123 build_identity_conv (TREE_TYPE (expr), expr));
1126 /* Merge it with the standard conversion sequence from the
1127 conversion function's return type to the desired type. */
1128 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1130 if (cand->viable == -1)
1133 return cand->second_conv;
1136 /* A reference of the indicated TYPE is being bound directly to the
1137 expression represented by the implicit conversion sequence CONV.
1138 Return a conversion sequence for this binding. */
1141 direct_reference_binding (tree type, conversion *conv)
1145 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1146 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1148 t = TREE_TYPE (type);
1152 When a parameter of reference type binds directly
1153 (_dcl.init.ref_) to an argument expression, the implicit
1154 conversion sequence is the identity conversion, unless the
1155 argument expression has a type that is a derived class of the
1156 parameter type, in which case the implicit conversion sequence is
1157 a derived-to-base Conversion.
1159 If the parameter binds directly to the result of applying a
1160 conversion function to the argument expression, the implicit
1161 conversion sequence is a user-defined conversion sequence
1162 (_over.ics.user_), with the second standard conversion sequence
1163 either an identity conversion or, if the conversion function
1164 returns an entity of a type that is a derived class of the
1165 parameter type, a derived-to-base conversion. */
1166 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1168 /* Represent the derived-to-base conversion. */
1169 conv = build_conv (ck_base, t, conv);
1170 /* We will actually be binding to the base-class subobject in
1171 the derived class, so we mark this conversion appropriately.
1172 That way, convert_like knows not to generate a temporary. */
1173 conv->need_temporary_p = false;
1175 return build_conv (ck_ref_bind, type, conv);
1178 /* Returns the conversion path from type FROM to reference type TO for
1179 purposes of reference binding. For lvalue binding, either pass a
1180 reference type to FROM or an lvalue expression to EXPR. If the
1181 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1182 the conversion returned. If C_CAST_P is true, this
1183 conversion is coming from a C-style cast. */
1186 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1188 conversion *conv = NULL;
1189 tree to = TREE_TYPE (rto);
1194 cp_lvalue_kind lvalue_p = clk_none;
1196 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1198 expr = instantiate_type (to, expr, tf_none);
1199 if (expr == error_mark_node)
1201 from = TREE_TYPE (expr);
1204 if (TREE_CODE (from) == REFERENCE_TYPE)
1206 /* Anything with reference type is an lvalue. */
1207 lvalue_p = clk_ordinary;
1208 from = TREE_TYPE (from);
1211 lvalue_p = real_lvalue_p (expr);
1214 if ((lvalue_p & clk_bitfield) != 0)
1215 tfrom = unlowered_expr_type (expr);
1217 /* Figure out whether or not the types are reference-related and
1218 reference compatible. We have do do this after stripping
1219 references from FROM. */
1220 related_p = reference_related_p (to, tfrom);
1221 /* If this is a C cast, first convert to an appropriately qualified
1222 type, so that we can later do a const_cast to the desired type. */
1223 if (related_p && c_cast_p
1224 && !at_least_as_qualified_p (to, tfrom))
1225 to = build_qualified_type (to, cp_type_quals (tfrom));
1226 compatible_p = reference_compatible_p (to, tfrom);
1228 /* Directly bind reference when target expression's type is compatible with
1229 the reference and expression is an lvalue. In DR391, the wording in
1230 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1231 const and rvalue references to rvalues of compatible class type. */
1234 || (!(flags & LOOKUP_NO_TEMP_BIND)
1235 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1236 && CLASS_TYPE_P (from))))
1240 If the initializer expression
1242 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1243 is reference-compatible with "cv2 T2,"
1245 the reference is bound directly to the initializer expression
1249 If the initializer expression is an rvalue, with T2 a class type,
1250 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1251 is bound to the object represented by the rvalue or to a sub-object
1252 within that object. */
1254 conv = build_identity_conv (tfrom, expr);
1255 conv = direct_reference_binding (rto, conv);
1257 if (flags & LOOKUP_PREFER_RVALUE)
1258 /* The top-level caller requested that we pretend that the lvalue
1259 be treated as an rvalue. */
1260 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1262 conv->rvaluedness_matches_p
1263 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1265 if ((lvalue_p & clk_bitfield) != 0
1266 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1267 /* For the purposes of overload resolution, we ignore the fact
1268 this expression is a bitfield or packed field. (In particular,
1269 [over.ics.ref] says specifically that a function with a
1270 non-const reference parameter is viable even if the
1271 argument is a bitfield.)
1273 However, when we actually call the function we must create
1274 a temporary to which to bind the reference. If the
1275 reference is volatile, or isn't const, then we cannot make
1276 a temporary, so we just issue an error when the conversion
1278 conv->need_temporary_p = true;
1282 /* [class.conv.fct] A conversion function is never used to convert a
1283 (possibly cv-qualified) object to the (possibly cv-qualified) same
1284 object type (or a reference to it), to a (possibly cv-qualified) base
1285 class of that type (or a reference to it).... */
1286 else if (CLASS_TYPE_P (from) && !related_p
1287 && !(flags & LOOKUP_NO_CONVERSION))
1291 If the initializer expression
1293 -- has a class type (i.e., T2 is a class type) can be
1294 implicitly converted to an lvalue of type "cv3 T3," where
1295 "cv1 T1" is reference-compatible with "cv3 T3". (this
1296 conversion is selected by enumerating the applicable
1297 conversion functions (_over.match.ref_) and choosing the
1298 best one through overload resolution. (_over.match_).
1300 the reference is bound to the lvalue result of the conversion
1301 in the second case. */
1302 conv = convert_class_to_reference (rto, from, expr);
1307 /* From this point on, we conceptually need temporaries, even if we
1308 elide them. Only the cases above are "direct bindings". */
1309 if (flags & LOOKUP_NO_TEMP_BIND)
1314 When a parameter of reference type is not bound directly to an
1315 argument expression, the conversion sequence is the one required
1316 to convert the argument expression to the underlying type of the
1317 reference according to _over.best.ics_. Conceptually, this
1318 conversion sequence corresponds to copy-initializing a temporary
1319 of the underlying type with the argument expression. Any
1320 difference in top-level cv-qualification is subsumed by the
1321 initialization itself and does not constitute a conversion. */
1325 Otherwise, the reference shall be to a non-volatile const type.
1327 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1328 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1333 Otherwise, a temporary of type "cv1 T1" is created and
1334 initialized from the initializer expression using the rules for a
1335 non-reference copy initialization. If T1 is reference-related to
1336 T2, cv1 must be the same cv-qualification as, or greater
1337 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1338 if (related_p && !at_least_as_qualified_p (to, from))
1341 /* We're generating a temporary now, but don't bind any more in the
1342 conversion (specifically, don't slice the temporary returned by a
1343 conversion operator). */
1344 flags |= LOOKUP_NO_TEMP_BIND;
1346 conv = implicit_conversion (to, from, expr, c_cast_p,
1351 conv = build_conv (ck_ref_bind, rto, conv);
1352 /* This reference binding, unlike those above, requires the
1353 creation of a temporary. */
1354 conv->need_temporary_p = true;
1355 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1360 /* Returns the implicit conversion sequence (see [over.ics]) from type
1361 FROM to type TO. The optional expression EXPR may affect the
1362 conversion. FLAGS are the usual overloading flags. Only
1363 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1364 conversion is coming from a C-style cast. */
1367 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1372 if (from == error_mark_node || to == error_mark_node
1373 || expr == error_mark_node)
1376 if (TREE_CODE (to) == REFERENCE_TYPE)
1377 conv = reference_binding (to, from, expr, c_cast_p, flags);
1379 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1384 if (is_std_init_list (to) && expr
1385 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1386 return build_list_conv (to, expr, flags);
1388 if (expr != NULL_TREE
1389 && (MAYBE_CLASS_TYPE_P (from)
1390 || MAYBE_CLASS_TYPE_P (to))
1391 && (flags & LOOKUP_NO_CONVERSION) == 0)
1393 struct z_candidate *cand;
1394 int convflags = ((flags & LOOKUP_NO_TEMP_BIND)
1395 |LOOKUP_ONLYCONVERTING);
1397 if (CLASS_TYPE_P (to)
1398 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1399 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1400 return build_aggr_conv (to, expr, flags);
1402 cand = build_user_type_conversion_1 (to, expr, convflags);
1404 conv = cand->second_conv;
1406 /* We used to try to bind a reference to a temporary here, but that
1407 is now handled after the recursive call to this function at the end
1408 of reference_binding. */
1415 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1418 static struct z_candidate *
1419 add_candidate (struct z_candidate **candidates,
1421 size_t num_convs, conversion **convs,
1422 tree access_path, tree conversion_path,
1425 struct z_candidate *cand = (struct z_candidate *)
1426 conversion_obstack_alloc (sizeof (struct z_candidate));
1430 cand->convs = convs;
1431 cand->num_convs = num_convs;
1432 cand->access_path = access_path;
1433 cand->conversion_path = conversion_path;
1434 cand->viable = viable;
1435 cand->next = *candidates;
1441 /* Create an overload candidate for the function or method FN called with
1442 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1443 to implicit_conversion.
1445 CTYPE, if non-NULL, is the type we want to pretend this function
1446 comes from for purposes of overload resolution. */
1448 static struct z_candidate *
1449 add_function_candidate (struct z_candidate **candidates,
1450 tree fn, tree ctype, tree arglist,
1451 tree access_path, tree conversion_path,
1454 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1457 tree parmnode, argnode;
1461 /* At this point we should not see any functions which haven't been
1462 explicitly declared, except for friend functions which will have
1463 been found using argument dependent lookup. */
1464 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1466 /* The `this', `in_chrg' and VTT arguments to constructors are not
1467 considered in overload resolution. */
1468 if (DECL_CONSTRUCTOR_P (fn))
1470 parmlist = skip_artificial_parms_for (fn, parmlist);
1471 orig_arglist = arglist;
1472 arglist = skip_artificial_parms_for (fn, arglist);
1475 orig_arglist = arglist;
1477 len = list_length (arglist);
1478 convs = alloc_conversions (len);
1480 /* 13.3.2 - Viable functions [over.match.viable]
1481 First, to be a viable function, a candidate function shall have enough
1482 parameters to agree in number with the arguments in the list.
1484 We need to check this first; otherwise, checking the ICSes might cause
1485 us to produce an ill-formed template instantiation. */
1487 parmnode = parmlist;
1488 for (i = 0; i < len; ++i)
1490 if (parmnode == NULL_TREE || parmnode == void_list_node)
1492 parmnode = TREE_CHAIN (parmnode);
1495 if (i < len && parmnode)
1498 /* Make sure there are default args for the rest of the parms. */
1499 else if (!sufficient_parms_p (parmnode))
1505 /* Second, for F to be a viable function, there shall exist for each
1506 argument an implicit conversion sequence that converts that argument
1507 to the corresponding parameter of F. */
1509 parmnode = parmlist;
1512 for (i = 0; i < len; ++i)
1514 tree arg = TREE_VALUE (argnode);
1515 tree argtype = lvalue_type (arg);
1519 if (parmnode == void_list_node)
1522 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1523 && ! DECL_CONSTRUCTOR_P (fn));
1527 tree parmtype = TREE_VALUE (parmnode);
1530 /* The type of the implicit object parameter ('this') for
1531 overload resolution is not always the same as for the
1532 function itself; conversion functions are considered to
1533 be members of the class being converted, and functions
1534 introduced by a using-declaration are considered to be
1535 members of the class that uses them.
1537 Since build_over_call ignores the ICS for the `this'
1538 parameter, we can just change the parm type. */
1539 if (ctype && is_this)
1542 = build_qualified_type (ctype,
1543 TYPE_QUALS (TREE_TYPE (parmtype)));
1544 parmtype = build_pointer_type (parmtype);
1547 if ((flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1548 && ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1549 lflags |= LOOKUP_NO_CONVERSION;
1551 t = implicit_conversion (parmtype, argtype, arg,
1552 /*c_cast_p=*/false, lflags);
1556 t = build_identity_conv (argtype, arg);
1557 t->ellipsis_p = true;
1574 parmnode = TREE_CHAIN (parmnode);
1575 argnode = TREE_CHAIN (argnode);
1579 return add_candidate (candidates, fn, orig_arglist, len, convs,
1580 access_path, conversion_path, viable);
1583 /* Create an overload candidate for the conversion function FN which will
1584 be invoked for expression OBJ, producing a pointer-to-function which
1585 will in turn be called with the argument list ARGLIST, and add it to
1586 CANDIDATES. FLAGS is passed on to implicit_conversion.
1588 Actually, we don't really care about FN; we care about the type it
1589 converts to. There may be multiple conversion functions that will
1590 convert to that type, and we rely on build_user_type_conversion_1 to
1591 choose the best one; so when we create our candidate, we record the type
1592 instead of the function. */
1594 static struct z_candidate *
1595 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1596 tree arglist, tree access_path, tree conversion_path)
1598 tree totype = TREE_TYPE (TREE_TYPE (fn));
1599 int i, len, viable, flags;
1600 tree parmlist, parmnode, argnode;
1603 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1604 parmlist = TREE_TYPE (parmlist);
1605 parmlist = TYPE_ARG_TYPES (parmlist);
1607 len = list_length (arglist) + 1;
1608 convs = alloc_conversions (len);
1609 parmnode = parmlist;
1612 flags = LOOKUP_NORMAL;
1614 /* Don't bother looking up the same type twice. */
1615 if (*candidates && (*candidates)->fn == totype)
1618 for (i = 0; i < len; ++i)
1620 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1621 tree argtype = lvalue_type (arg);
1625 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1627 else if (parmnode == void_list_node)
1630 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1631 /*c_cast_p=*/false, flags);
1634 t = build_identity_conv (argtype, arg);
1635 t->ellipsis_p = true;
1649 parmnode = TREE_CHAIN (parmnode);
1650 argnode = TREE_CHAIN (argnode);
1656 if (!sufficient_parms_p (parmnode))
1659 return add_candidate (candidates, totype, arglist, len, convs,
1660 access_path, conversion_path, viable);
1664 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1665 tree type1, tree type2, tree *args, tree *argtypes,
1677 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1678 convs = alloc_conversions (num_convs);
1680 for (i = 0; i < 2; ++i)
1685 t = implicit_conversion (types[i], argtypes[i], args[i],
1686 /*c_cast_p=*/false, flags);
1690 /* We need something for printing the candidate. */
1691 t = build_identity_conv (types[i], NULL_TREE);
1698 /* For COND_EXPR we rearranged the arguments; undo that now. */
1701 convs[2] = convs[1];
1702 convs[1] = convs[0];
1703 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1704 /*c_cast_p=*/false, flags);
1711 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1713 /*access_path=*/NULL_TREE,
1714 /*conversion_path=*/NULL_TREE,
1719 is_complete (tree t)
1721 return COMPLETE_TYPE_P (complete_type (t));
1724 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1727 promoted_arithmetic_type_p (tree type)
1731 In this section, the term promoted integral type is used to refer
1732 to those integral types which are preserved by integral promotion
1733 (including e.g. int and long but excluding e.g. char).
1734 Similarly, the term promoted arithmetic type refers to promoted
1735 integral types plus floating types. */
1736 return ((INTEGRAL_TYPE_P (type)
1737 && same_type_p (type_promotes_to (type), type))
1738 || TREE_CODE (type) == REAL_TYPE);
1741 /* Create any builtin operator overload candidates for the operator in
1742 question given the converted operand types TYPE1 and TYPE2. The other
1743 args are passed through from add_builtin_candidates to
1744 build_builtin_candidate.
1746 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1747 If CODE is requires candidates operands of the same type of the kind
1748 of which TYPE1 and TYPE2 are, we add both candidates
1749 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1752 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1753 enum tree_code code2, tree fnname, tree type1,
1754 tree type2, tree *args, tree *argtypes, int flags)
1758 case POSTINCREMENT_EXPR:
1759 case POSTDECREMENT_EXPR:
1760 args[1] = integer_zero_node;
1761 type2 = integer_type_node;
1770 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1771 and VQ is either volatile or empty, there exist candidate operator
1772 functions of the form
1773 VQ T& operator++(VQ T&);
1774 T operator++(VQ T&, int);
1775 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1776 type other than bool, and VQ is either volatile or empty, there exist
1777 candidate operator functions of the form
1778 VQ T& operator--(VQ T&);
1779 T operator--(VQ T&, int);
1780 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1781 complete object type, and VQ is either volatile or empty, there exist
1782 candidate operator functions of the form
1783 T*VQ& operator++(T*VQ&);
1784 T*VQ& operator--(T*VQ&);
1785 T* operator++(T*VQ&, int);
1786 T* operator--(T*VQ&, int); */
1788 case POSTDECREMENT_EXPR:
1789 case PREDECREMENT_EXPR:
1790 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1792 case POSTINCREMENT_EXPR:
1793 case PREINCREMENT_EXPR:
1794 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1796 type1 = build_reference_type (type1);
1801 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1802 exist candidate operator functions of the form
1806 8 For every function type T, there exist candidate operator functions of
1808 T& operator*(T*); */
1811 if (TREE_CODE (type1) == POINTER_TYPE
1812 && (TYPE_PTROB_P (type1)
1813 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1817 /* 9 For every type T, there exist candidate operator functions of the form
1820 10For every promoted arithmetic type T, there exist candidate operator
1821 functions of the form
1825 case UNARY_PLUS_EXPR: /* unary + */
1826 if (TREE_CODE (type1) == POINTER_TYPE)
1829 if (ARITHMETIC_TYPE_P (type1))
1833 /* 11For every promoted integral type T, there exist candidate operator
1834 functions of the form
1838 if (INTEGRAL_TYPE_P (type1))
1842 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1843 is the same type as C2 or is a derived class of C2, T is a complete
1844 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1845 there exist candidate operator functions of the form
1846 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1847 where CV12 is the union of CV1 and CV2. */
1850 if (TREE_CODE (type1) == POINTER_TYPE
1851 && TYPE_PTR_TO_MEMBER_P (type2))
1853 tree c1 = TREE_TYPE (type1);
1854 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1856 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1857 && (TYPE_PTRMEMFUNC_P (type2)
1858 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1863 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1864 didate operator functions of the form
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 bool operator!=(L, R);
1875 where LR is the result of the usual arithmetic conversions between
1878 14For every pair of types T and I, where T is a cv-qualified or cv-
1879 unqualified complete object type and I is a promoted integral type,
1880 there exist candidate operator functions of the form
1881 T* operator+(T*, I);
1882 T& operator[](T*, I);
1883 T* operator-(T*, I);
1884 T* operator+(I, T*);
1885 T& operator[](I, T*);
1887 15For every T, where T is a pointer to complete object type, there exist
1888 candidate operator functions of the form112)
1889 ptrdiff_t operator-(T, T);
1891 16For every pointer or enumeration type T, there exist candidate operator
1892 functions of the form
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);
1898 bool operator!=(T, T);
1900 17For every pointer to member type T, there exist candidate operator
1901 functions of the form
1902 bool operator==(T, T);
1903 bool operator!=(T, T); */
1906 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1908 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1910 type2 = ptrdiff_type_node;
1914 case TRUNC_DIV_EXPR:
1915 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1921 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1922 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1924 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1929 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1941 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1943 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1945 if (TREE_CODE (type1) == ENUMERAL_TYPE
1946 && TREE_CODE (type2) == ENUMERAL_TYPE)
1948 if (TYPE_PTR_P (type1)
1949 && null_ptr_cst_p (args[1])
1950 && !uses_template_parms (type1))
1955 if (null_ptr_cst_p (args[0])
1956 && TYPE_PTR_P (type2)
1957 && !uses_template_parms (type2))
1965 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1968 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1970 type1 = ptrdiff_type_node;
1973 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1975 type2 = ptrdiff_type_node;
1980 /* 18For every pair of promoted integral types L and R, there exist candi-
1981 date operator functions of the form
1988 where LR is the result of the usual arithmetic conversions between
1991 case TRUNC_MOD_EXPR:
1997 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2001 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2002 type, VQ is either volatile or empty, and R is a promoted arithmetic
2003 type, there exist candidate operator functions of the form
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);
2008 VQ L& operator-=(VQ L&, R);
2010 20For every pair T, VQ), where T is any type and VQ is either volatile
2011 or empty, there exist candidate operator functions of the form
2012 T*VQ& operator=(T*VQ&, T*);
2014 21For every pair T, VQ), where T is a pointer to member type and VQ is
2015 either volatile or empty, there exist candidate operator functions of
2017 VQ T& operator=(VQ T&, T);
2019 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2020 unqualified complete object type, VQ is either volatile or empty, and
2021 I is a promoted integral type, there exist candidate operator func-
2023 T*VQ& operator+=(T*VQ&, I);
2024 T*VQ& operator-=(T*VQ&, I);
2026 23For every triple L, VQ, R), where L is an integral or enumeration
2027 type, VQ is either volatile or empty, and R is a promoted integral
2028 type, there exist candidate operator functions of the form
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);
2035 VQ L& operator|=(VQ L&, R); */
2042 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
2044 type2 = ptrdiff_type_node;
2048 case TRUNC_DIV_EXPR:
2049 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2053 case TRUNC_MOD_EXPR:
2059 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
2064 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2066 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2067 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2068 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2069 || ((TYPE_PTRMEMFUNC_P (type1)
2070 || TREE_CODE (type1) == POINTER_TYPE)
2071 && null_ptr_cst_p (args[1])))
2081 type1 = build_reference_type (type1);
2087 For every pair of promoted arithmetic types L and R, there
2088 exist candidate operator functions of the form
2090 LR operator?(bool, L, R);
2092 where LR is the result of the usual arithmetic conversions
2093 between types L and R.
2095 For every type T, where T is a pointer or pointer-to-member
2096 type, there exist candidate operator functions of the form T
2097 operator?(bool, T, T); */
2099 if (promoted_arithmetic_type_p (type1)
2100 && promoted_arithmetic_type_p (type2))
2104 /* Otherwise, the types should be pointers. */
2105 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2106 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2109 /* We don't check that the two types are the same; the logic
2110 below will actually create two candidates; one in which both
2111 parameter types are TYPE1, and one in which both parameter
2119 /* If we're dealing with two pointer types or two enumeral types,
2120 we need candidates for both of them. */
2121 if (type2 && !same_type_p (type1, type2)
2122 && TREE_CODE (type1) == TREE_CODE (type2)
2123 && (TREE_CODE (type1) == REFERENCE_TYPE
2124 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2125 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2126 || TYPE_PTRMEMFUNC_P (type1)
2127 || MAYBE_CLASS_TYPE_P (type1)
2128 || TREE_CODE (type1) == ENUMERAL_TYPE))
2130 build_builtin_candidate
2131 (candidates, fnname, type1, type1, args, argtypes, flags);
2132 build_builtin_candidate
2133 (candidates, fnname, type2, type2, args, argtypes, flags);
2137 build_builtin_candidate
2138 (candidates, fnname, type1, type2, args, argtypes, flags);
2142 type_decays_to (tree type)
2144 if (TREE_CODE (type) == ARRAY_TYPE)
2145 return build_pointer_type (TREE_TYPE (type));
2146 if (TREE_CODE (type) == FUNCTION_TYPE)
2147 return build_pointer_type (type);
2151 /* There are three conditions of builtin candidates:
2153 1) bool-taking candidates. These are the same regardless of the input.
2154 2) pointer-pair taking candidates. These are generated for each type
2155 one of the input types converts to.
2156 3) arithmetic candidates. According to the standard, we should generate
2157 all of these, but I'm trying not to...
2159 Here we generate a superset of the possible candidates for this particular
2160 case. That is a subset of the full set the standard defines, plus some
2161 other cases which the standard disallows. add_builtin_candidate will
2162 filter out the invalid set. */
2165 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2166 enum tree_code code2, tree fnname, tree *args,
2171 tree type, argtypes[3];
2172 /* TYPES[i] is the set of possible builtin-operator parameter types
2173 we will consider for the Ith argument. These are represented as
2174 a TREE_LIST; the TREE_VALUE of each node is the potential
2178 for (i = 0; i < 3; ++i)
2181 argtypes[i] = unlowered_expr_type (args[i]);
2183 argtypes[i] = NULL_TREE;
2188 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2189 and VQ is either volatile or empty, there exist candidate operator
2190 functions of the form
2191 VQ T& operator++(VQ T&); */
2193 case POSTINCREMENT_EXPR:
2194 case PREINCREMENT_EXPR:
2195 case POSTDECREMENT_EXPR:
2196 case PREDECREMENT_EXPR:
2201 /* 24There also exist candidate operator functions of the form
2202 bool operator!(bool);
2203 bool operator&&(bool, bool);
2204 bool operator||(bool, bool); */
2206 case TRUTH_NOT_EXPR:
2207 build_builtin_candidate
2208 (candidates, fnname, boolean_type_node,
2209 NULL_TREE, args, argtypes, flags);
2212 case TRUTH_ORIF_EXPR:
2213 case TRUTH_ANDIF_EXPR:
2214 build_builtin_candidate
2215 (candidates, fnname, boolean_type_node,
2216 boolean_type_node, args, argtypes, flags);
2238 types[0] = types[1] = NULL_TREE;
2240 for (i = 0; i < 2; ++i)
2244 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2248 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2251 convs = lookup_conversions (argtypes[i]);
2253 if (code == COND_EXPR)
2255 if (real_lvalue_p (args[i]))
2256 types[i] = tree_cons
2257 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2259 types[i] = tree_cons
2260 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2266 for (; convs; convs = TREE_CHAIN (convs))
2268 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2271 && (TREE_CODE (type) != REFERENCE_TYPE
2272 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2275 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2276 types[i] = tree_cons (NULL_TREE, type, types[i]);
2278 type = non_reference (type);
2279 if (i != 0 || ! ref1)
2281 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2282 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2283 types[i] = tree_cons (NULL_TREE, type, types[i]);
2284 if (INTEGRAL_TYPE_P (type))
2285 type = type_promotes_to (type);
2288 if (! value_member (type, types[i]))
2289 types[i] = tree_cons (NULL_TREE, type, types[i]);
2294 if (code == COND_EXPR && real_lvalue_p (args[i]))
2295 types[i] = tree_cons
2296 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2297 type = non_reference (argtypes[i]);
2298 if (i != 0 || ! ref1)
2300 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2301 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2302 types[i] = tree_cons (NULL_TREE, type, types[i]);
2303 if (INTEGRAL_TYPE_P (type))
2304 type = type_promotes_to (type);
2306 types[i] = tree_cons (NULL_TREE, type, types[i]);
2310 /* Run through the possible parameter types of both arguments,
2311 creating candidates with those parameter types. */
2312 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2315 for (type = types[1]; type; type = TREE_CHAIN (type))
2316 add_builtin_candidate
2317 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2318 TREE_VALUE (type), args, argtypes, flags);
2320 add_builtin_candidate
2321 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2322 NULL_TREE, args, argtypes, flags);
2327 /* If TMPL can be successfully instantiated as indicated by
2328 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2330 TMPL is the template. EXPLICIT_TARGS are any explicit template
2331 arguments. ARGLIST is the arguments provided at the call-site.
2332 The RETURN_TYPE is the desired type for conversion operators. If
2333 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2334 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2335 add_conv_candidate. */
2337 static struct z_candidate*
2338 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2339 tree ctype, tree explicit_targs, tree arglist,
2340 tree return_type, tree access_path,
2341 tree conversion_path, int flags, tree obj,
2342 unification_kind_t strict)
2344 int ntparms = DECL_NTPARMS (tmpl);
2345 tree targs = make_tree_vec (ntparms);
2346 tree args_without_in_chrg = arglist;
2347 struct z_candidate *cand;
2351 /* We don't do deduction on the in-charge parameter, the VTT
2352 parameter or 'this'. */
2353 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2354 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2356 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2357 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2358 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2359 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2361 i = fn_type_unification (tmpl, explicit_targs, targs,
2362 args_without_in_chrg,
2363 return_type, strict, flags);
2368 fn = instantiate_template (tmpl, targs, tf_none);
2369 if (fn == error_mark_node)
2374 A member function template is never instantiated to perform the
2375 copy of a class object to an object of its class type.
2377 It's a little unclear what this means; the standard explicitly
2378 does allow a template to be used to copy a class. For example,
2383 template <class T> A(const T&);
2386 void g () { A a (f ()); }
2388 the member template will be used to make the copy. The section
2389 quoted above appears in the paragraph that forbids constructors
2390 whose only parameter is (a possibly cv-qualified variant of) the
2391 class type, and a logical interpretation is that the intent was
2392 to forbid the instantiation of member templates which would then
2394 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2396 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2397 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2402 if (obj != NULL_TREE)
2403 /* Aha, this is a conversion function. */
2404 cand = add_conv_candidate (candidates, fn, obj, access_path,
2405 conversion_path, arglist);
2407 cand = add_function_candidate (candidates, fn, ctype,
2408 arglist, access_path,
2409 conversion_path, flags);
2410 if (DECL_TI_TEMPLATE (fn) != tmpl)
2411 /* This situation can occur if a member template of a template
2412 class is specialized. Then, instantiate_template might return
2413 an instantiation of the specialization, in which case the
2414 DECL_TI_TEMPLATE field will point at the original
2415 specialization. For example:
2417 template <class T> struct S { template <class U> void f(U);
2418 template <> void f(int) {}; };
2422 Here, TMPL will be template <class U> S<double>::f(U).
2423 And, instantiate template will give us the specialization
2424 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2425 for this will point at template <class T> template <> S<T>::f(int),
2426 so that we can find the definition. For the purposes of
2427 overload resolution, however, we want the original TMPL. */
2428 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2430 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2436 static struct z_candidate *
2437 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2438 tree explicit_targs, tree arglist, tree return_type,
2439 tree access_path, tree conversion_path, int flags,
2440 unification_kind_t strict)
2443 add_template_candidate_real (candidates, tmpl, ctype,
2444 explicit_targs, arglist, return_type,
2445 access_path, conversion_path,
2446 flags, NULL_TREE, strict);
2450 static struct z_candidate *
2451 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2452 tree obj, tree arglist, tree return_type,
2453 tree access_path, tree conversion_path)
2456 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2457 arglist, return_type, access_path,
2458 conversion_path, 0, obj, DEDUCE_CONV);
2461 /* The CANDS are the set of candidates that were considered for
2462 overload resolution. Return the set of viable candidates. If none
2463 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2464 is true if a candidate should be considered viable only if it is
2467 static struct z_candidate*
2468 splice_viable (struct z_candidate *cands,
2472 struct z_candidate *viable;
2473 struct z_candidate **last_viable;
2474 struct z_candidate **cand;
2477 last_viable = &viable;
2478 *any_viable_p = false;
2483 struct z_candidate *c = *cand;
2484 if (strict_p ? c->viable == 1 : c->viable)
2489 last_viable = &c->next;
2490 *any_viable_p = true;
2496 return viable ? viable : cands;
2500 any_strictly_viable (struct z_candidate *cands)
2502 for (; cands; cands = cands->next)
2503 if (cands->viable == 1)
2508 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2509 words, it is about to become the "this" pointer for a member
2510 function call. Take the address of the object. */
2513 build_this (tree obj)
2515 /* In a template, we are only concerned about the type of the
2516 expression, so we can take a shortcut. */
2517 if (processing_template_decl)
2518 return build_address (obj);
2520 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2523 /* Returns true iff functions are equivalent. Equivalent functions are
2524 not '==' only if one is a function-local extern function or if
2525 both are extern "C". */
2528 equal_functions (tree fn1, tree fn2)
2530 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2531 || DECL_EXTERN_C_FUNCTION_P (fn1))
2532 return decls_match (fn1, fn2);
2536 /* Print information about one overload candidate CANDIDATE. MSGSTR
2537 is the text to print before the candidate itself.
2539 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2540 to have been run through gettext by the caller. This wart makes
2541 life simpler in print_z_candidates and for the translators. */
2544 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2546 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2548 if (candidate->num_convs == 3)
2549 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2550 candidate->convs[0]->type,
2551 candidate->convs[1]->type,
2552 candidate->convs[2]->type);
2553 else if (candidate->num_convs == 2)
2554 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2555 candidate->convs[0]->type,
2556 candidate->convs[1]->type);
2558 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2559 candidate->convs[0]->type);
2561 else if (TYPE_P (candidate->fn))
2562 inform ("%s %T <conversion>", msgstr, candidate->fn);
2563 else if (candidate->viable == -1)
2564 inform ("%s %+#D <near match>", msgstr, candidate->fn);
2566 inform ("%s %+#D", msgstr, candidate->fn);
2570 print_z_candidates (struct z_candidate *candidates)
2573 struct z_candidate *cand1;
2574 struct z_candidate **cand2;
2576 /* There may be duplicates in the set of candidates. We put off
2577 checking this condition as long as possible, since we have no way
2578 to eliminate duplicates from a set of functions in less than n^2
2579 time. Now we are about to emit an error message, so it is more
2580 permissible to go slowly. */
2581 for (cand1 = candidates; cand1; cand1 = cand1->next)
2583 tree fn = cand1->fn;
2584 /* Skip builtin candidates and conversion functions. */
2585 if (TREE_CODE (fn) != FUNCTION_DECL)
2587 cand2 = &cand1->next;
2590 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2591 && equal_functions (fn, (*cand2)->fn))
2592 *cand2 = (*cand2)->next;
2594 cand2 = &(*cand2)->next;
2601 str = _("candidates are:");
2602 print_z_candidate (str, candidates);
2603 if (candidates->next)
2605 /* Indent successive candidates by the width of the translation
2606 of the above string. */
2607 size_t len = gcc_gettext_width (str) + 1;
2608 char *spaces = (char *) alloca (len);
2609 memset (spaces, ' ', len-1);
2610 spaces[len - 1] = '\0';
2612 candidates = candidates->next;
2615 print_z_candidate (spaces, candidates);
2616 candidates = candidates->next;
2622 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2623 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2624 the result of the conversion function to convert it to the final
2625 desired type. Merge the two sequences into a single sequence,
2626 and return the merged sequence. */
2629 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2633 gcc_assert (user_seq->kind == ck_user);
2635 /* Find the end of the second conversion sequence. */
2637 while ((*t)->kind != ck_identity)
2638 t = &((*t)->u.next);
2640 /* Replace the identity conversion with the user conversion
2644 /* The entire sequence is a user-conversion sequence. */
2645 std_seq->user_conv_p = true;
2650 /* Returns the best overload candidate to perform the requested
2651 conversion. This function is used for three the overloading situations
2652 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2653 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2654 per [dcl.init.ref], so we ignore temporary bindings. */
2656 static struct z_candidate *
2657 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2659 struct z_candidate *candidates, *cand;
2660 tree fromtype = TREE_TYPE (expr);
2661 tree ctors = NULL_TREE;
2662 tree conv_fns = NULL_TREE;
2663 conversion *conv = NULL;
2664 tree args = NULL_TREE;
2668 /* We represent conversion within a hierarchy using RVALUE_CONV and
2669 BASE_CONV, as specified by [over.best.ics]; these become plain
2670 constructor calls, as specified in [dcl.init]. */
2671 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2672 || !DERIVED_FROM_P (totype, fromtype));
2674 if (MAYBE_CLASS_TYPE_P (totype))
2675 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2677 if (MAYBE_CLASS_TYPE_P (fromtype))
2679 tree to_nonref = non_reference (totype);
2680 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2681 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2682 && DERIVED_FROM_P (to_nonref, fromtype)))
2684 /* [class.conv.fct] A conversion function is never used to
2685 convert a (possibly cv-qualified) object to the (possibly
2686 cv-qualified) same object type (or a reference to it), to a
2687 (possibly cv-qualified) base class of that type (or a
2688 reference to it)... */
2691 conv_fns = lookup_conversions (fromtype);
2695 flags |= LOOKUP_NO_CONVERSION;
2697 /* It's OK to bind a temporary for converting constructor arguments, but
2698 not in converting the return value of a conversion operator. */
2699 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2700 flags &= ~LOOKUP_NO_TEMP_BIND;
2706 ctors = BASELINK_FUNCTIONS (ctors);
2708 t = build_int_cst (build_pointer_type (totype), 0);
2709 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2710 && !TYPE_HAS_LIST_CTOR (totype))
2712 args = ctor_to_list (expr);
2713 /* We still allow more conversions within an init-list. */
2714 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2715 /* But not for the copy ctor. */
2716 |LOOKUP_NO_COPY_CTOR_CONVERSION
2717 |LOOKUP_NO_NARROWING);
2720 args = build_tree_list (NULL_TREE, expr);
2721 /* We should never try to call the abstract or base constructor
2723 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2724 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2725 args = tree_cons (NULL_TREE, t, args);
2727 for (; ctors; ctors = OVL_NEXT (ctors))
2729 tree ctor = OVL_CURRENT (ctors);
2730 if (DECL_NONCONVERTING_P (ctor)
2731 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2734 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2735 cand = add_template_candidate (&candidates, ctor, totype,
2736 NULL_TREE, args, NULL_TREE,
2737 TYPE_BINFO (totype),
2738 TYPE_BINFO (totype),
2742 cand = add_function_candidate (&candidates, ctor, totype,
2743 args, TYPE_BINFO (totype),
2744 TYPE_BINFO (totype),
2749 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2751 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2752 set, then this is copy-initialization. In that case, "The
2753 result of the call is then used to direct-initialize the
2754 object that is the destination of the copy-initialization."
2757 We represent this in the conversion sequence with an
2758 rvalue conversion, which means a constructor call. */
2759 if (TREE_CODE (totype) != REFERENCE_TYPE
2760 && !(convflags & LOOKUP_NO_TEMP_BIND))
2762 = build_conv (ck_rvalue, totype, cand->second_conv);
2767 args = build_tree_list (NULL_TREE, build_this (expr));
2769 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2772 tree conversion_path = TREE_PURPOSE (conv_fns);
2774 /* If we are called to convert to a reference type, we are trying to
2775 find an lvalue binding, so don't even consider temporaries. If
2776 we don't find an lvalue binding, the caller will try again to
2777 look for a temporary binding. */
2778 if (TREE_CODE (totype) == REFERENCE_TYPE)
2779 convflags |= LOOKUP_NO_TEMP_BIND;
2781 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2783 tree fn = OVL_CURRENT (fns);
2785 /* [over.match.funcs] For conversion functions, the function
2786 is considered to be a member of the class of the implicit
2787 object argument for the purpose of defining the type of
2788 the implicit object parameter.
2790 So we pass fromtype as CTYPE to add_*_candidate. */
2792 if (TREE_CODE (fn) == TEMPLATE_DECL)
2793 cand = add_template_candidate (&candidates, fn, fromtype,
2796 TYPE_BINFO (fromtype),
2801 cand = add_function_candidate (&candidates, fn, fromtype,
2803 TYPE_BINFO (fromtype),
2810 = implicit_conversion (totype,
2811 TREE_TYPE (TREE_TYPE (cand->fn)),
2813 /*c_cast_p=*/false, convflags);
2815 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2816 copy-initialization. In that case, "The result of the
2817 call is then used to direct-initialize the object that is
2818 the destination of the copy-initialization." [dcl.init]
2820 We represent this in the conversion sequence with an
2821 rvalue conversion, which means a constructor call. But
2822 don't add a second rvalue conversion if there's already
2823 one there. Which there really shouldn't be, but it's
2824 harmless since we'd add it here anyway. */
2825 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2826 && !(convflags & LOOKUP_NO_TEMP_BIND))
2827 ics = build_conv (ck_rvalue, totype, ics);
2829 cand->second_conv = ics;
2833 else if (candidates->viable == 1 && ics->bad_p)
2839 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2843 cand = tourney (candidates);
2846 if (flags & LOOKUP_COMPLAIN)
2848 error ("conversion from %qT to %qT is ambiguous",
2850 print_z_candidates (candidates);
2853 cand = candidates; /* any one will do */
2854 cand->second_conv = build_ambiguous_conv (totype, expr);
2855 cand->second_conv->user_conv_p = true;
2856 if (!any_strictly_viable (candidates))
2857 cand->second_conv->bad_p = true;
2858 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2859 ambiguous conversion is no worse than another user-defined
2865 /* Build the user conversion sequence. */
2868 (DECL_CONSTRUCTOR_P (cand->fn)
2869 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2870 build_identity_conv (TREE_TYPE (expr), expr));
2873 /* Combine it with the second conversion sequence. */
2874 cand->second_conv = merge_conversion_sequences (conv,
2877 if (cand->viable == -1)
2878 cand->second_conv->bad_p = true;
2884 build_user_type_conversion (tree totype, tree expr, int flags)
2886 struct z_candidate *cand
2887 = build_user_type_conversion_1 (totype, expr, flags);
2891 if (cand->second_conv->kind == ck_ambig)
2892 return error_mark_node;
2893 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
2894 return convert_from_reference (expr);
2899 /* Do any initial processing on the arguments to a function call. */
2902 resolve_args (tree args)
2905 for (t = args; t; t = TREE_CHAIN (t))
2907 tree arg = TREE_VALUE (t);
2909 if (error_operand_p (arg))
2910 return error_mark_node;
2911 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2913 error ("invalid use of void expression");
2914 return error_mark_node;
2916 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
2917 return error_mark_node;
2922 /* Perform overload resolution on FN, which is called with the ARGS.
2924 Return the candidate function selected by overload resolution, or
2925 NULL if the event that overload resolution failed. In the case
2926 that overload resolution fails, *CANDIDATES will be the set of
2927 candidates considered, and ANY_VIABLE_P will be set to true or
2928 false to indicate whether or not any of the candidates were
2931 The ARGS should already have gone through RESOLVE_ARGS before this
2932 function is called. */
2934 static struct z_candidate *
2935 perform_overload_resolution (tree fn,
2937 struct z_candidate **candidates,
2940 struct z_candidate *cand;
2941 tree explicit_targs = NULL_TREE;
2942 int template_only = 0;
2945 *any_viable_p = true;
2947 /* Check FN and ARGS. */
2948 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2949 || TREE_CODE (fn) == TEMPLATE_DECL
2950 || TREE_CODE (fn) == OVERLOAD
2951 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2952 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2954 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2956 explicit_targs = TREE_OPERAND (fn, 1);
2957 fn = TREE_OPERAND (fn, 0);
2961 /* Add the various candidate functions. */
2962 add_candidates (fn, args, explicit_targs, template_only,
2963 /*conversion_path=*/NULL_TREE,
2964 /*access_path=*/NULL_TREE,
2968 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2972 cand = tourney (*candidates);
2976 /* Return an expression for a call to FN (a namespace-scope function,
2977 or a static member function) with the ARGS. */
2980 build_new_function_call (tree fn, tree args, bool koenig_p,
2981 tsubst_flags_t complain)
2983 struct z_candidate *candidates, *cand;
2988 args = resolve_args (args);
2989 if (args == error_mark_node)
2990 return error_mark_node;
2992 /* If this function was found without using argument dependent
2993 lookup, then we want to ignore any undeclared friend
2999 fn = remove_hidden_names (fn);
3002 if (complain & tf_error)
3003 error ("no matching function for call to %<%D(%A)%>",
3004 DECL_NAME (OVL_CURRENT (orig_fn)), args);
3005 return error_mark_node;
3009 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3010 p = conversion_obstack_alloc (0);
3012 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
3016 if (complain & tf_error)
3018 if (!any_viable_p && candidates && ! candidates->next)
3019 return cp_build_function_call (candidates->fn, args, complain);
3020 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3021 fn = TREE_OPERAND (fn, 0);
3023 error ("no matching function for call to %<%D(%A)%>",
3024 DECL_NAME (OVL_CURRENT (fn)), args);
3026 error ("call of overloaded %<%D(%A)%> is ambiguous",
3027 DECL_NAME (OVL_CURRENT (fn)), args);
3029 print_z_candidates (candidates);
3031 result = error_mark_node;
3034 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3036 /* Free all the conversions we allocated. */
3037 obstack_free (&conversion_obstack, p);
3042 /* Build a call to a global operator new. FNNAME is the name of the
3043 operator (either "operator new" or "operator new[]") and ARGS are
3044 the arguments provided. *SIZE points to the total number of bytes
3045 required by the allocation, and is updated if that is changed here.
3046 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
3047 function determines that no cookie should be used, after all,
3048 *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be
3049 set, upon return, to the allocation function called. */
3052 build_operator_new_call (tree fnname, tree args,
3053 tree *size, tree *cookie_size,
3057 struct z_candidate *candidates;
3058 struct z_candidate *cand;
3063 args = tree_cons (NULL_TREE, *size, args);
3064 args = resolve_args (args);
3065 if (args == error_mark_node)
3072 If this lookup fails to find the name, or if the allocated type
3073 is not a class type, the allocation function's name is looked
3074 up in the global scope.
3076 we disregard block-scope declarations of "operator new". */
3077 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
3079 /* Figure out what function is being called. */
3080 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
3082 /* If no suitable function could be found, issue an error message
3087 error ("no matching function for call to %<%D(%A)%>",
3088 DECL_NAME (OVL_CURRENT (fns)), args);
3090 error ("call of overloaded %<%D(%A)%> is ambiguous",
3091 DECL_NAME (OVL_CURRENT (fns)), args);
3093 print_z_candidates (candidates);
3094 return error_mark_node;
3097 /* If a cookie is required, add some extra space. Whether
3098 or not a cookie is required cannot be determined until
3099 after we know which function was called. */
3102 bool use_cookie = true;
3103 if (!abi_version_at_least (2))
3105 tree placement = TREE_CHAIN (args);
3106 /* In G++ 3.2, the check was implemented incorrectly; it
3107 looked at the placement expression, rather than the
3108 type of the function. */
3109 if (placement && !TREE_CHAIN (placement)
3110 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
3118 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3119 /* Skip the size_t parameter. */
3120 arg_types = TREE_CHAIN (arg_types);
3121 /* Check the remaining parameters (if any). */
3123 && TREE_CHAIN (arg_types) == void_list_node
3124 && same_type_p (TREE_VALUE (arg_types),
3128 /* If we need a cookie, adjust the number of bytes allocated. */
3131 /* Update the total size. */
3132 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3133 /* Update the argument list to reflect the adjusted size. */
3134 TREE_VALUE (args) = *size;
3137 *cookie_size = NULL_TREE;
3140 /* Tell our caller which function we decided to call. */
3144 /* Build the CALL_EXPR. */
3145 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3149 build_object_call (tree obj, tree args, tsubst_flags_t complain)
3151 struct z_candidate *candidates = 0, *cand;
3152 tree fns, convs, mem_args = NULL_TREE;
3153 tree type = TREE_TYPE (obj);
3155 tree result = NULL_TREE;
3158 if (TYPE_PTRMEMFUNC_P (type))
3160 if (complain & tf_error)
3161 /* It's no good looking for an overloaded operator() on a
3162 pointer-to-member-function. */
3163 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3164 return error_mark_node;
3167 if (TYPE_BINFO (type))
3169 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3170 if (fns == error_mark_node)
3171 return error_mark_node;
3176 args = resolve_args (args);
3178 if (args == error_mark_node)
3179 return error_mark_node;
3181 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3182 p = conversion_obstack_alloc (0);
3186 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3187 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
3189 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3191 tree fn = OVL_CURRENT (fns);
3192 if (TREE_CODE (fn) == TEMPLATE_DECL)
3193 add_template_candidate (&candidates, fn, base, NULL_TREE,
3194 mem_args, NULL_TREE,
3197 LOOKUP_NORMAL, DEDUCE_CALL);
3199 add_function_candidate
3200 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
3201 TYPE_BINFO (type), LOOKUP_NORMAL);
3205 convs = lookup_conversions (type);
3207 for (; convs; convs = TREE_CHAIN (convs))
3209 tree fns = TREE_VALUE (convs);
3210 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
3212 if ((TREE_CODE (totype) == POINTER_TYPE
3213 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3214 || (TREE_CODE (totype) == REFERENCE_TYPE
3215 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3216 || (TREE_CODE (totype) == REFERENCE_TYPE
3217 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3218 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3219 for (; fns; fns = OVL_NEXT (fns))
3221 tree fn = OVL_CURRENT (fns);
3222 if (TREE_CODE (fn) == TEMPLATE_DECL)
3223 add_template_conv_candidate
3224 (&candidates, fn, obj, args, totype,
3225 /*access_path=*/NULL_TREE,
3226 /*conversion_path=*/NULL_TREE);
3228 add_conv_candidate (&candidates, fn, obj, args,
3229 /*conversion_path=*/NULL_TREE,
3230 /*access_path=*/NULL_TREE);
3234 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3237 if (complain & tf_error)
3239 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3240 print_z_candidates (candidates);
3242 result = error_mark_node;
3246 cand = tourney (candidates);
3249 if (complain & tf_error)
3251 error ("call of %<(%T) (%A)%> is ambiguous",
3252 TREE_TYPE (obj), args);
3253 print_z_candidates (candidates);
3255 result = error_mark_node;
3257 /* Since cand->fn will be a type, not a function, for a conversion
3258 function, we must be careful not to unconditionally look at
3260 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3261 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3262 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3265 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3267 obj = convert_from_reference (obj);
3268 result = cp_build_function_call (obj, args, complain);
3272 /* Free all the conversions we allocated. */
3273 obstack_free (&conversion_obstack, p);
3279 op_error (enum tree_code code, enum tree_code code2,
3280 tree arg1, tree arg2, tree arg3, const char *problem)
3284 if (code == MODIFY_EXPR)
3285 opname = assignment_operator_name_info[code2].name;
3287 opname = operator_name_info[code].name;
3292 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3293 problem, arg1, arg2, arg3);
3296 case POSTINCREMENT_EXPR:
3297 case POSTDECREMENT_EXPR:
3298 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3302 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3307 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3312 error ("%s for %<operator%s%> in %<%E %s %E%>",
3313 problem, opname, arg1, opname, arg2);
3315 error ("%s for %<operator%s%> in %<%s%E%>",
3316 problem, opname, opname, arg1);
3321 /* Return the implicit conversion sequence that could be used to
3322 convert E1 to E2 in [expr.cond]. */
3325 conditional_conversion (tree e1, tree e2)
3327 tree t1 = non_reference (TREE_TYPE (e1));
3328 tree t2 = non_reference (TREE_TYPE (e2));
3334 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3335 implicitly converted (clause _conv_) to the type "reference to
3336 T2", subject to the constraint that in the conversion the
3337 reference must bind directly (_dcl.init.ref_) to E1. */
3338 if (real_lvalue_p (e2))
3340 conv = implicit_conversion (build_reference_type (t2),
3344 LOOKUP_NO_TEMP_BIND);
3351 If E1 and E2 have class type, and the underlying class types are
3352 the same or one is a base class of the other: E1 can be converted
3353 to match E2 if the class of T2 is the same type as, or a base
3354 class of, the class of T1, and the cv-qualification of T2 is the
3355 same cv-qualification as, or a greater cv-qualification than, the
3356 cv-qualification of T1. If the conversion is applied, E1 is
3357 changed to an rvalue of type T2 that still refers to the original
3358 source class object (or the appropriate subobject thereof). */
3359 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3360 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3362 if (good_base && at_least_as_qualified_p (t2, t1))
3364 conv = build_identity_conv (t1, e1);
3365 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3366 TYPE_MAIN_VARIANT (t2)))
3367 conv = build_conv (ck_base, t2, conv);
3369 conv = build_conv (ck_rvalue, t2, conv);
3378 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3379 converted to the type that expression E2 would have if E2 were
3380 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3381 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3385 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3386 arguments to the conditional expression. */
3389 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3390 tsubst_flags_t complain)
3394 tree result = NULL_TREE;
3395 tree result_type = NULL_TREE;
3396 bool lvalue_p = true;
3397 struct z_candidate *candidates = 0;
3398 struct z_candidate *cand;
3401 /* As a G++ extension, the second argument to the conditional can be
3402 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3403 c'.) If the second operand is omitted, make sure it is
3404 calculated only once. */
3407 if (complain & tf_error)
3408 pedwarn (OPT_pedantic,
3409 "ISO C++ forbids omitting the middle term of a ?: expression");
3411 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3412 if (real_lvalue_p (arg1))
3413 arg2 = arg1 = stabilize_reference (arg1);
3415 arg2 = arg1 = save_expr (arg1);
3420 The first expression is implicitly converted to bool (clause
3422 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3424 /* If something has already gone wrong, just pass that fact up the
3426 if (error_operand_p (arg1)
3427 || error_operand_p (arg2)
3428 || error_operand_p (arg3))
3429 return error_mark_node;
3433 If either the second or the third operand has type (possibly
3434 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3435 array-to-pointer (_conv.array_), and function-to-pointer
3436 (_conv.func_) standard conversions are performed on the second
3437 and third operands. */
3438 arg2_type = unlowered_expr_type (arg2);
3439 arg3_type = unlowered_expr_type (arg3);
3440 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3442 /* Do the conversions. We don't these for `void' type arguments
3443 since it can't have any effect and since decay_conversion
3444 does not handle that case gracefully. */
3445 if (!VOID_TYPE_P (arg2_type))
3446 arg2 = decay_conversion (arg2);
3447 if (!VOID_TYPE_P (arg3_type))
3448 arg3 = decay_conversion (arg3);
3449 arg2_type = TREE_TYPE (arg2);
3450 arg3_type = TREE_TYPE (arg3);
3454 One of the following shall hold:
3456 --The second or the third operand (but not both) is a
3457 throw-expression (_except.throw_); the result is of the
3458 type of the other and is an rvalue.
3460 --Both the second and the third operands have type void; the
3461 result is of type void and is an rvalue.
3463 We must avoid calling force_rvalue for expressions of type
3464 "void" because it will complain that their value is being
3466 if (TREE_CODE (arg2) == THROW_EXPR
3467 && TREE_CODE (arg3) != THROW_EXPR)
3469 if (!VOID_TYPE_P (arg3_type))
3470 arg3 = force_rvalue (arg3);
3471 arg3_type = TREE_TYPE (arg3);
3472 result_type = arg3_type;
3474 else if (TREE_CODE (arg2) != THROW_EXPR
3475 && TREE_CODE (arg3) == THROW_EXPR)
3477 if (!VOID_TYPE_P (arg2_type))
3478 arg2 = force_rvalue (arg2);
3479 arg2_type = TREE_TYPE (arg2);
3480 result_type = arg2_type;
3482 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3483 result_type = void_type_node;
3486 if (complain & tf_error)
3488 if (VOID_TYPE_P (arg2_type))
3489 error ("second operand to the conditional operator "
3490 "is of type %<void%>, "
3491 "but the third operand is neither a throw-expression "
3492 "nor of type %<void%>");
3494 error ("third operand to the conditional operator "
3495 "is of type %<void%>, "
3496 "but the second operand is neither a throw-expression "
3497 "nor of type %<void%>");
3499 return error_mark_node;
3503 goto valid_operands;
3507 Otherwise, if the second and third operand have different types,
3508 and either has (possibly cv-qualified) class type, an attempt is
3509 made to convert each of those operands to the type of the other. */
3510 else if (!same_type_p (arg2_type, arg3_type)
3511 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3516 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3517 p = conversion_obstack_alloc (0);
3519 conv2 = conditional_conversion (arg2, arg3);
3520 conv3 = conditional_conversion (arg3, arg2);
3524 If both can be converted, or one can be converted but the
3525 conversion is ambiguous, the program is ill-formed. If
3526 neither can be converted, the operands are left unchanged and
3527 further checking is performed as described below. If exactly
3528 one conversion is possible, that conversion is applied to the
3529 chosen operand and the converted operand is used in place of
3530 the original operand for the remainder of this section. */
3531 if ((conv2 && !conv2->bad_p
3532 && conv3 && !conv3->bad_p)
3533 || (conv2 && conv2->kind == ck_ambig)
3534 || (conv3 && conv3->kind == ck_ambig))
3536 error ("operands to ?: have different types %qT and %qT",
3537 arg2_type, arg3_type);
3538 result = error_mark_node;
3540 else if (conv2 && (!conv2->bad_p || !conv3))
3542 arg2 = convert_like (conv2, arg2, complain);
3543 arg2 = convert_from_reference (arg2);
3544 arg2_type = TREE_TYPE (arg2);
3545 /* Even if CONV2 is a valid conversion, the result of the
3546 conversion may be invalid. For example, if ARG3 has type
3547 "volatile X", and X does not have a copy constructor
3548 accepting a "volatile X&", then even if ARG2 can be
3549 converted to X, the conversion will fail. */
3550 if (error_operand_p (arg2))
3551 result = error_mark_node;
3553 else if (conv3 && (!conv3->bad_p || !conv2))
3555 arg3 = convert_like (conv3, arg3, complain);
3556 arg3 = convert_from_reference (arg3);
3557 arg3_type = TREE_TYPE (arg3);
3558 if (error_operand_p (arg3))
3559 result = error_mark_node;
3562 /* Free all the conversions we allocated. */
3563 obstack_free (&conversion_obstack, p);
3568 /* If, after the conversion, both operands have class type,
3569 treat the cv-qualification of both operands as if it were the
3570 union of the cv-qualification of the operands.
3572 The standard is not clear about what to do in this
3573 circumstance. For example, if the first operand has type
3574 "const X" and the second operand has a user-defined
3575 conversion to "volatile X", what is the type of the second
3576 operand after this step? Making it be "const X" (matching
3577 the first operand) seems wrong, as that discards the
3578 qualification without actually performing a copy. Leaving it
3579 as "volatile X" seems wrong as that will result in the
3580 conditional expression failing altogether, even though,
3581 according to this step, the one operand could be converted to
3582 the type of the other. */
3583 if ((conv2 || conv3)
3584 && CLASS_TYPE_P (arg2_type)
3585 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3586 arg2_type = arg3_type =
3587 cp_build_qualified_type (arg2_type,
3588 TYPE_QUALS (arg2_type)
3589 | TYPE_QUALS (arg3_type));
3594 If the second and third operands are lvalues and have the same
3595 type, the result is of that type and is an lvalue. */
3596 if (real_lvalue_p (arg2)
3597 && real_lvalue_p (arg3)
3598 && same_type_p (arg2_type, arg3_type))
3600 result_type = arg2_type;
3601 goto valid_operands;
3606 Otherwise, the result is an rvalue. If the second and third
3607 operand do not have the same type, and either has (possibly
3608 cv-qualified) class type, overload resolution is used to
3609 determine the conversions (if any) to be applied to the operands
3610 (_over.match.oper_, _over.built_). */
3612 if (!same_type_p (arg2_type, arg3_type)
3613 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3619 /* Rearrange the arguments so that add_builtin_candidate only has
3620 to know about two args. In build_builtin_candidates, the
3621 arguments are unscrambled. */
3625 add_builtin_candidates (&candidates,
3628 ansi_opname (COND_EXPR),
3634 If the overload resolution fails, the program is
3636 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3639 if (complain & tf_error)
3641 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3642 print_z_candidates (candidates);
3644 return error_mark_node;
3646 cand = tourney (candidates);
3649 if (complain & tf_error)
3651 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3652 print_z_candidates (candidates);
3654 return error_mark_node;
3659 Otherwise, the conversions thus determined are applied, and
3660 the converted operands are used in place of the original
3661 operands for the remainder of this section. */
3662 conv = cand->convs[0];
3663 arg1 = convert_like (conv, arg1, complain);
3664 conv = cand->convs[1];
3665 arg2 = convert_like (conv, arg2, complain);
3666 conv = cand->convs[2];
3667 arg3 = convert_like (conv, arg3, complain);
3672 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3673 and function-to-pointer (_conv.func_) standard conversions are
3674 performed on the second and third operands.
3676 We need to force the lvalue-to-rvalue conversion here for class types,
3677 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3678 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3681 arg2 = force_rvalue (arg2);
3682 if (!CLASS_TYPE_P (arg2_type))
3683 arg2_type = TREE_TYPE (arg2);
3685 arg3 = force_rvalue (arg3);
3686 if (!CLASS_TYPE_P (arg2_type))
3687 arg3_type = TREE_TYPE (arg3);
3689 if (arg2 == error_mark_node || arg3 == error_mark_node)
3690 return error_mark_node;
3694 After those conversions, one of the following shall hold:
3696 --The second and third operands have the same type; the result is of
3698 if (same_type_p (arg2_type, arg3_type))
3699 result_type = arg2_type;
3702 --The second and third operands have arithmetic or enumeration
3703 type; the usual arithmetic conversions are performed to bring
3704 them to a common type, and the result is of that type. */
3705 else if ((ARITHMETIC_TYPE_P (arg2_type)
3706 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3707 && (ARITHMETIC_TYPE_P (arg3_type)
3708 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3710 /* In this case, there is always a common type. */
3711 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3714 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3715 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3717 if (complain & tf_warning)
3719 "enumeral mismatch in conditional expression: %qT vs %qT",
3720 arg2_type, arg3_type);
3722 else if (extra_warnings
3723 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3724 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3725 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3726 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3728 if (complain & tf_warning)
3730 "enumeral and non-enumeral type in conditional expression");
3733 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3734 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3738 --The second and third operands have pointer type, or one has
3739 pointer type and the other is a null pointer constant; pointer
3740 conversions (_conv.ptr_) and qualification conversions
3741 (_conv.qual_) are performed to bring them to their composite
3742 pointer type (_expr.rel_). The result is of the composite
3745 --The second and third operands have pointer to member type, or
3746 one has pointer to member type and the other is a null pointer
3747 constant; pointer to member conversions (_conv.mem_) and
3748 qualification conversions (_conv.qual_) are performed to bring
3749 them to a common type, whose cv-qualification shall match the
3750 cv-qualification of either the second or the third operand.
3751 The result is of the common type. */
3752 else if ((null_ptr_cst_p (arg2)
3753 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3754 || (null_ptr_cst_p (arg3)
3755 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3756 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3757 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3758 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3760 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3761 arg3, "conditional expression",
3763 if (result_type == error_mark_node)
3764 return error_mark_node;
3765 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3766 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3771 if (complain & tf_error)
3772 error ("operands to ?: have different types %qT and %qT",
3773 arg2_type, arg3_type);
3774 return error_mark_node;
3778 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3780 /* We can't use result_type below, as fold might have returned a
3785 /* Expand both sides into the same slot, hopefully the target of
3786 the ?: expression. We used to check for TARGET_EXPRs here,
3787 but now we sometimes wrap them in NOP_EXPRs so the test would
3789 if (CLASS_TYPE_P (TREE_TYPE (result)))
3790 result = get_target_expr (result);
3791 /* If this expression is an rvalue, but might be mistaken for an
3792 lvalue, we must add a NON_LVALUE_EXPR. */
3793 result = rvalue (result);
3799 /* OPERAND is an operand to an expression. Perform necessary steps
3800 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3804 prep_operand (tree operand)
3808 if (CLASS_TYPE_P (TREE_TYPE (operand))
3809 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3810 /* Make sure the template type is instantiated now. */
3811 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3817 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3818 OVERLOAD) to the CANDIDATES, returning an updated list of
3819 CANDIDATES. The ARGS are the arguments provided to the call,
3820 without any implicit object parameter. The EXPLICIT_TARGS are
3821 explicit template arguments provided. TEMPLATE_ONLY is true if
3822 only template functions should be considered. CONVERSION_PATH,
3823 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3826 add_candidates (tree fns, tree args,
3827 tree explicit_targs, bool template_only,
3828 tree conversion_path, tree access_path,
3830 struct z_candidate **candidates)
3833 tree non_static_args;
3835 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3836 /* Delay creating the implicit this parameter until it is needed. */
3837 non_static_args = NULL_TREE;
3844 fn = OVL_CURRENT (fns);
3845 /* Figure out which set of arguments to use. */
3846 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3848 /* If this function is a non-static member, prepend the implicit
3849 object parameter. */
3850 if (!non_static_args)
3851 non_static_args = tree_cons (NULL_TREE,
3852 build_this (TREE_VALUE (args)),
3854 fn_args = non_static_args;
3857 /* Otherwise, just use the list of arguments provided. */
3860 if (TREE_CODE (fn) == TEMPLATE_DECL)
3861 add_template_candidate (candidates,
3871 else if (!template_only)
3872 add_function_candidate (candidates,
3879 fns = OVL_NEXT (fns);
3884 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3885 bool *overloaded_p, tsubst_flags_t complain)
3887 struct z_candidate *candidates = 0, *cand;
3888 tree arglist, fnname;
3890 tree result = NULL_TREE;
3891 bool result_valid_p = false;
3892 enum tree_code code2 = NOP_EXPR;
3897 bool expl_eq_arg1 = false;
3899 if (error_operand_p (arg1)
3900 || error_operand_p (arg2)
3901 || error_operand_p (arg3))
3902 return error_mark_node;
3904 if (code == MODIFY_EXPR)
3906 code2 = TREE_CODE (arg3);
3908 fnname = ansi_assopname (code2);
3911 fnname = ansi_opname (code);
3913 arg1 = prep_operand (arg1);
3919 case VEC_DELETE_EXPR:
3921 /* Use build_op_new_call and build_op_delete_call instead. */
3925 return build_object_call (arg1, arg2, complain);
3927 case TRUTH_ORIF_EXPR:
3928 case TRUTH_ANDIF_EXPR:
3929 case TRUTH_AND_EXPR:
3931 if (COMPARISON_CLASS_P (arg1))
3932 expl_eq_arg1 = true;
3937 arg2 = prep_operand (arg2);
3938 arg3 = prep_operand (arg3);
3940 if (code == COND_EXPR)
3942 if (arg2 == NULL_TREE
3943 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3944 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3945 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3946 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3949 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3950 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3953 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3954 arg2 = integer_zero_node;
3956 arglist = NULL_TREE;
3958 arglist = tree_cons (NULL_TREE, arg3, arglist);
3960 arglist = tree_cons (NULL_TREE, arg2, arglist);
3961 arglist = tree_cons (NULL_TREE, arg1, arglist);
3963 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3964 p = conversion_obstack_alloc (0);
3966 /* Add namespace-scope operators to the list of functions to
3968 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3969 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3970 flags, &candidates);
3971 /* Add class-member operators to the candidate set. */
3972 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3976 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3977 if (fns == error_mark_node)
3979 result = error_mark_node;
3980 goto user_defined_result_ready;
3983 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3985 BASELINK_BINFO (fns),
3986 TYPE_BINFO (TREE_TYPE (arg1)),
3987 flags, &candidates);
3990 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3991 to know about two args; a builtin candidate will always have a first
3992 parameter of type bool. We'll handle that in
3993 build_builtin_candidate. */
3994 if (code == COND_EXPR)
4004 args[2] = NULL_TREE;
4007 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4013 /* For these, the built-in candidates set is empty
4014 [over.match.oper]/3. We don't want non-strict matches
4015 because exact matches are always possible with built-in
4016 operators. The built-in candidate set for COMPONENT_REF
4017 would be empty too, but since there are no such built-in
4018 operators, we accept non-strict matches for them. */
4023 strict_p = pedantic;
4027 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4032 case POSTINCREMENT_EXPR:
4033 case POSTDECREMENT_EXPR:
4034 /* Don't try anything fancy if we're not allowed to produce
4036 if (!(complain & tf_error))
4037 return error_mark_node;
4039 /* Look for an `operator++ (int)'. If they didn't have
4040 one, then we fall back to the old way of doing things. */
4041 if (flags & LOOKUP_COMPLAIN)
4042 permerror ("no %<%D(int)%> declared for postfix %qs, "
4043 "trying prefix operator instead",
4045 operator_name_info[code].name);
4046 if (code == POSTINCREMENT_EXPR)
4047 code = PREINCREMENT_EXPR;
4049 code = PREDECREMENT_EXPR;
4050 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4051 overloaded_p, complain);
4054 /* The caller will deal with these. */
4059 result_valid_p = true;
4063 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4065 op_error (code, code2, arg1, arg2, arg3, "no match");
4066 print_z_candidates (candidates);
4068 result = error_mark_node;
4074 cand = tourney (candidates);
4077 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4079 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4080 print_z_candidates (candidates);
4082 result = error_mark_node;
4084 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4087 *overloaded_p = true;
4089 if (resolve_args (arglist) == error_mark_node)
4090 result = error_mark_node;
4092 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4096 /* Give any warnings we noticed during overload resolution. */
4097 if (cand->warnings && (complain & tf_warning))
4099 struct candidate_warning *w;
4100 for (w = cand->warnings; w; w = w->next)
4101 joust (cand, w->loser, 1);
4104 /* Check for comparison of different enum types. */
4113 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4114 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4115 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4116 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4117 && (complain & tf_warning))
4119 warning (OPT_Wenum_compare,
4120 "comparison between %q#T and %q#T",
4121 TREE_TYPE (arg1), TREE_TYPE (arg2));
4128 /* We need to strip any leading REF_BIND so that bitfields
4129 don't cause errors. This should not remove any important
4130 conversions, because builtins don't apply to class
4131 objects directly. */
4132 conv = cand->convs[0];
4133 if (conv->kind == ck_ref_bind)
4134 conv = conv->u.next;
4135 arg1 = convert_like (conv, arg1, complain);
4138 conv = cand->convs[1];
4139 if (conv->kind == ck_ref_bind)
4140 conv = conv->u.next;
4141 arg2 = convert_like (conv, arg2, complain);
4145 conv = cand->convs[2];
4146 if (conv->kind == ck_ref_bind)
4147 conv = conv->u.next;
4148 arg3 = convert_like (conv, arg3, complain);
4153 if (complain & tf_warning)
4154 warn_logical_operator (code, arg1, arg2);
4155 expl_eq_arg1 = true;
4160 user_defined_result_ready:
4162 /* Free all the conversions we allocated. */
4163 obstack_free (&conversion_obstack, p);
4165 if (result || result_valid_p)
4172 return cp_build_modify_expr (arg1, code2, arg2, complain);
4175 return cp_build_indirect_ref (arg1, "unary *", complain);
4177 case TRUTH_ANDIF_EXPR:
4178 case TRUTH_ORIF_EXPR:
4179 case TRUTH_AND_EXPR:
4182 warn_logical_operator (code, arg1, arg2);
4186 case TRUNC_DIV_EXPR:
4197 case TRUNC_MOD_EXPR:
4201 return cp_build_binary_op (code, arg1, arg2, complain);
4203 case UNARY_PLUS_EXPR:
4206 case TRUTH_NOT_EXPR:
4207 case PREINCREMENT_EXPR:
4208 case POSTINCREMENT_EXPR:
4209 case PREDECREMENT_EXPR:
4210 case POSTDECREMENT_EXPR:
4213 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4216 return build_array_ref (arg1, arg2);
4219 return build_conditional_expr (arg1, arg2, arg3, complain);
4222 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4226 /* The caller will deal with these. */
4238 /* Build a call to operator delete. This has to be handled very specially,
4239 because the restrictions on what signatures match are different from all
4240 other call instances. For a normal delete, only a delete taking (void *)
4241 or (void *, size_t) is accepted. For a placement delete, only an exact
4242 match with the placement new is accepted.
4244 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4245 ADDR is the pointer to be deleted.
4246 SIZE is the size of the memory block to be deleted.
4247 GLOBAL_P is true if the delete-expression should not consider
4248 class-specific delete operators.
4249 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4251 If this call to "operator delete" is being generated as part to
4252 deallocate memory allocated via a new-expression (as per [expr.new]
4253 which requires that if the initialization throws an exception then
4254 we call a deallocation function), then ALLOC_FN is the allocation
4258 build_op_delete_call (enum tree_code code, tree addr, tree size,
4259 bool global_p, tree placement,
4262 tree fn = NULL_TREE;
4263 tree fns, fnname, argtypes, type;
4266 if (addr == error_mark_node)
4267 return error_mark_node;
4269 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4271 fnname = ansi_opname (code);
4273 if (CLASS_TYPE_P (type)
4274 && COMPLETE_TYPE_P (complete_type (type))
4278 If the result of the lookup is ambiguous or inaccessible, or if
4279 the lookup selects a placement deallocation function, the
4280 program is ill-formed.
4282 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4284 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4285 if (fns == error_mark_node)
4286 return error_mark_node;
4291 if (fns == NULL_TREE)
4292 fns = lookup_name_nonclass (fnname);
4294 /* Strip const and volatile from addr. */
4295 addr = cp_convert (ptr_type_node, addr);
4299 /* Get the parameter types for the allocation function that is
4301 gcc_assert (alloc_fn != NULL_TREE);
4302 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4306 /* First try it without the size argument. */
4307 argtypes = void_list_node;
4310 /* We make two tries at finding a matching `operator delete'. On
4311 the first pass, we look for a one-operator (or placement)
4312 operator delete. If we're not doing placement delete, then on
4313 the second pass we look for a two-argument delete. */
4314 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4316 /* Go through the `operator delete' functions looking for one
4317 with a matching type. */
4318 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4324 /* The first argument must be "void *". */
4325 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4326 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4329 /* On the first pass, check the rest of the arguments. */
4335 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4343 /* On the second pass, look for a function with exactly two
4344 arguments: "void *" and "size_t". */
4346 /* For "operator delete(void *, ...)" there will be
4347 no second argument, but we will not get an exact
4350 && same_type_p (TREE_VALUE (t), size_type_node)
4351 && TREE_CHAIN (t) == void_list_node)
4355 /* If we found a match, we're done. */
4360 /* If we have a matching function, call it. */
4363 /* Make sure we have the actual function, and not an
4365 fn = OVL_CURRENT (fn);
4367 /* If the FN is a member function, make sure that it is
4369 if (DECL_CLASS_SCOPE_P (fn))
4370 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4374 /* The placement args might not be suitable for overload
4375 resolution at this point, so build the call directly. */
4376 int nargs = call_expr_nargs (placement);
4377 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4380 for (i = 1; i < nargs; i++)
4381 argarray[i] = CALL_EXPR_ARG (placement, i);
4383 return build_cxx_call (fn, nargs, argarray);
4389 args = tree_cons (NULL_TREE, addr, NULL_TREE);
4391 args = tree_cons (NULL_TREE, addr,
4392 build_tree_list (NULL_TREE, size));
4393 return cp_build_function_call (fn, args, tf_warning_or_error);
4399 If no unambiguous matching deallocation function can be found,
4400 propagating the exception does not cause the object's memory to
4405 warning (0, "no corresponding deallocation function for %qD",
4410 error ("no suitable %<operator %s%> for %qT",
4411 operator_name_info[(int)code].name, type);
4412 return error_mark_node;
4415 /* If the current scope isn't allowed to access DECL along
4416 BASETYPE_PATH, give an error. The most derived class in
4417 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4418 the declaration to use in the error diagnostic. */
4421 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4423 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4425 if (!accessible_p (basetype_path, decl, true))
4427 if (TREE_PRIVATE (decl))
4428 error ("%q+#D is private", diag_decl);
4429 else if (TREE_PROTECTED (decl))
4430 error ("%q+#D is protected", diag_decl);
4432 error ("%q+#D is inaccessible", diag_decl);
4433 error ("within this context");
4440 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4441 bitwise or of LOOKUP_* values. If any errors are warnings are
4442 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4443 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4447 build_temp (tree expr, tree type, int flags,
4448 diagnostic_fn_t *diagnostic_fn)
4452 savew = warningcount, savee = errorcount;
4453 expr = build_special_member_call (NULL_TREE,
4454 complete_ctor_identifier,
4455 build_tree_list (NULL_TREE, expr),
4456 type, flags, tf_warning_or_error);
4457 if (warningcount > savew)
4458 *diagnostic_fn = warning0;
4459 else if (errorcount > savee)
4460 *diagnostic_fn = error;
4462 *diagnostic_fn = NULL;
4466 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4467 EXPR is implicitly converted to type TOTYPE.
4468 FN and ARGNUM are used for diagnostics. */
4471 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4473 tree t = non_reference (totype);
4475 /* Issue warnings about peculiar, but valid, uses of NULL. */
4476 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4479 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4482 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4485 /* Issue warnings if "false" is converted to a NULL pointer */
4486 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4487 warning (OPT_Wconversion,
4488 "converting %<false%> to pointer type for argument %P of %qD",
4492 /* Perform the conversions in CONVS on the expression EXPR. FN and
4493 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4494 indicates the `this' argument of a method. INNER is nonzero when
4495 being called to continue a conversion chain. It is negative when a
4496 reference binding will be applied, positive otherwise. If
4497 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4498 conversions will be emitted if appropriate. If C_CAST_P is true,
4499 this conversion is coming from a C-style cast; in that case,
4500 conversions to inaccessible bases are permitted. */
4503 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4504 int inner, bool issue_conversion_warnings,
4505 bool c_cast_p, tsubst_flags_t complain)
4507 tree totype = convs->type;
4508 diagnostic_fn_t diagnostic_fn;
4512 && convs->kind != ck_user
4513 && convs->kind != ck_ambig
4514 && convs->kind != ck_ref_bind
4515 && convs->kind != ck_rvalue
4516 && convs->kind != ck_base)
4518 conversion *t = convs;
4519 for (; t; t = convs->u.next)
4521 if (t->kind == ck_user || !t->bad_p)
4523 expr = convert_like_real (t, expr, fn, argnum, 1,
4524 /*issue_conversion_warnings=*/false,
4529 else if (t->kind == ck_ambig)
4530 return convert_like_real (t, expr, fn, argnum, 1,
4531 /*issue_conversion_warnings=*/false,
4534 else if (t->kind == ck_identity)
4537 if (complain & tf_error)
4539 permerror ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4541 permerror (" initializing argument %P of %qD", argnum, fn);
4544 return error_mark_node;
4546 return cp_convert (totype, expr);
4549 if (issue_conversion_warnings && (complain & tf_warning))
4550 conversion_null_warnings (totype, expr, fn, argnum);
4552 switch (convs->kind)
4556 struct z_candidate *cand = convs->cand;
4557 tree convfn = cand->fn;
4560 /* When converting from an init list we consider explicit
4561 constructors, but actually trying to call one is an error. */
4562 if (DECL_NONCONVERTING_P (convfn))
4564 if (complain & tf_error)
4565 error ("converting to %qT from initializer list would use "
4566 "explicit constructor %qD", totype, convfn);
4568 return error_mark_node;
4571 /* Set user_conv_p on the argument conversions, so rvalue/base
4572 handling knows not to allow any more UDCs. */
4573 for (i = 0; i < cand->num_convs; ++i)
4574 cand->convs[i]->user_conv_p = true;
4576 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4578 /* If this is a constructor or a function returning an aggr type,
4579 we need to build up a TARGET_EXPR. */
4580 if (DECL_CONSTRUCTOR_P (convfn))
4581 expr = build_cplus_new (totype, expr);
4586 if (type_unknown_p (expr))
4587 expr = instantiate_type (totype, expr, complain);
4588 /* Convert a constant to its underlying value, unless we are
4589 about to bind it to a reference, in which case we need to
4590 leave it as an lvalue. */
4593 expr = decl_constant_value (expr);
4594 if (expr == null_node && INTEGRAL_TYPE_P (totype))
4595 /* If __null has been converted to an integer type, we do not
4596 want to warn about uses of EXPR as an integer, rather than
4598 expr = build_int_cst (totype, 0);
4602 /* Call build_user_type_conversion again for the error. */
4603 return build_user_type_conversion
4604 (totype, convs->u.expr, LOOKUP_NORMAL);
4608 /* Conversion to std::initializer_list<T>. */
4609 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4610 tree new_ctor = build_constructor (init_list_type_node, NULL);
4611 unsigned len = CONSTRUCTOR_NELTS (expr);
4612 tree array, parms, val;
4615 /* Convert all the elements. */
4616 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4618 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4619 1, false, false, complain);
4620 if (sub == error_mark_node)
4622 check_narrowing (TREE_TYPE (sub), val);
4623 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4625 /* Build up the array. */
4626 elttype = cp_build_qualified_type
4627 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4628 array = build_array_of_n_type (elttype, len);
4629 array = finish_compound_literal (array, new_ctor);
4631 parms = build_tree_list (NULL_TREE, size_int (len));
4632 parms = tree_cons (NULL_TREE, decay_conversion (array), parms);
4633 /* Call the private constructor. */
4634 push_deferring_access_checks (dk_no_check);
4635 new_ctor = build_special_member_call
4636 (NULL_TREE, complete_ctor_identifier, parms, totype, 0, complain);
4637 pop_deferring_access_checks ();
4638 return build_cplus_new (totype, new_ctor);
4642 return get_target_expr (digest_init (totype, expr));
4648 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4649 convs->kind == ck_ref_bind ? -1 : 1,
4650 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4653 if (expr == error_mark_node)
4654 return error_mark_node;
4656 switch (convs->kind)
4659 expr = convert_bitfield_to_declared_type (expr);
4660 if (! MAYBE_CLASS_TYPE_P (totype))
4662 /* Else fall through. */
4664 if (convs->kind == ck_base && !convs->need_temporary_p)
4666 /* We are going to bind a reference directly to a base-class
4667 subobject of EXPR. */
4668 /* Build an expression for `*((base*) &expr)'. */
4669 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4670 expr = convert_to_base (expr, build_pointer_type (totype),
4671 !c_cast_p, /*nonnull=*/true);
4672 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4676 /* Copy-initialization where the cv-unqualified version of the source
4677 type is the same class as, or a derived class of, the class of the
4678 destination [is treated as direct-initialization]. [dcl.init] */
4679 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4680 if (convs->user_conv_p)
4681 /* This conversion is being done in the context of a user-defined
4682 conversion (i.e. the second step of copy-initialization), so
4683 don't allow any more. */
4684 flags |= LOOKUP_NO_CONVERSION;
4685 expr = build_temp (expr, totype, flags, &diagnostic_fn);
4686 if (diagnostic_fn && fn)
4688 if ((complain & tf_error))
4689 diagnostic_fn (" initializing argument %P of %qD", argnum, fn);
4690 else if (diagnostic_fn == 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 ("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 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);
6653 inform (" because conversion sequence for the argument is better");
6663 F1 is a non-template function and F2 is a template function
6666 if (!cand1->template_decl && cand2->template_decl)
6668 else if (cand1->template_decl && !cand2->template_decl)
6672 F1 and F2 are template functions and the function template for F1 is
6673 more specialized than the template for F2 according to the partial
6676 if (cand1->template_decl && cand2->template_decl)
6678 winner = more_specialized_fn
6679 (TI_TEMPLATE (cand1->template_decl),
6680 TI_TEMPLATE (cand2->template_decl),
6681 /* [temp.func.order]: The presence of unused ellipsis and default
6682 arguments has no effect on the partial ordering of function
6683 templates. add_function_candidate() will not have
6684 counted the "this" argument for constructors. */
6685 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6691 the context is an initialization by user-defined conversion (see
6692 _dcl.init_ and _over.match.user_) and the standard conversion
6693 sequence from the return type of F1 to the destination type (i.e.,
6694 the type of the entity being initialized) is a better conversion
6695 sequence than the standard conversion sequence from the return type
6696 of F2 to the destination type. */
6698 if (cand1->second_conv)
6700 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6705 /* Check whether we can discard a builtin candidate, either because we
6706 have two identical ones or matching builtin and non-builtin candidates.
6708 (Pedantically in the latter case the builtin which matched the user
6709 function should not be added to the overload set, but we spot it here.
6712 ... the builtin candidates include ...
6713 - do not have the same parameter type list as any non-template
6714 non-member candidate. */
6716 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6717 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6719 for (i = 0; i < len; ++i)
6720 if (!same_type_p (cand1->convs[i]->type,
6721 cand2->convs[i]->type))
6723 if (i == cand1->num_convs)
6725 if (cand1->fn == cand2->fn)
6726 /* Two built-in candidates; arbitrarily pick one. */
6728 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6729 /* cand1 is built-in; prefer cand2. */
6732 /* cand2 is built-in; prefer cand1. */
6737 /* If the two functions are the same (this can happen with declarations
6738 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6739 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6740 && equal_functions (cand1->fn, cand2->fn))
6745 /* Extension: If the worst conversion for one candidate is worse than the
6746 worst conversion for the other, take the first. */
6749 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6750 struct z_candidate *w = 0, *l = 0;
6752 for (i = 0; i < len; ++i)
6754 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6755 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6756 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6757 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6760 winner = 1, w = cand1, l = cand2;
6762 winner = -1, w = cand2, l = cand1;
6768 "ISO C++ says that these are ambiguous, even "
6769 "though the worst conversion for the first is better than "
6770 "the worst conversion for the second:");
6771 print_z_candidate (_("candidate 1:"), w);
6772 print_z_candidate (_("candidate 2:"), l);
6780 gcc_assert (!winner);
6784 /* Given a list of candidates for overloading, find the best one, if any.
6785 This algorithm has a worst case of O(2n) (winner is last), and a best
6786 case of O(n/2) (totally ambiguous); much better than a sorting
6789 static struct z_candidate *
6790 tourney (struct z_candidate *candidates)
6792 struct z_candidate *champ = candidates, *challenger;
6794 int champ_compared_to_predecessor = 0;
6796 /* Walk through the list once, comparing each current champ to the next
6797 candidate, knocking out a candidate or two with each comparison. */
6799 for (challenger = champ->next; challenger; )
6801 fate = joust (champ, challenger, 0);
6803 challenger = challenger->next;
6808 champ = challenger->next;
6811 champ_compared_to_predecessor = 0;
6816 champ_compared_to_predecessor = 1;
6819 challenger = champ->next;
6823 /* Make sure the champ is better than all the candidates it hasn't yet
6824 been compared to. */
6826 for (challenger = candidates;
6828 && !(champ_compared_to_predecessor && challenger->next == champ);
6829 challenger = challenger->next)
6831 fate = joust (champ, challenger, 0);
6839 /* Returns nonzero if things of type FROM can be converted to TO. */
6842 can_convert (tree to, tree from)
6844 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6847 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6850 can_convert_arg (tree to, tree from, tree arg, int flags)
6856 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6857 p = conversion_obstack_alloc (0);
6859 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6861 ok_p = (t && !t->bad_p);
6863 /* Free all the conversions we allocated. */
6864 obstack_free (&conversion_obstack, p);
6869 /* Like can_convert_arg, but allows dubious conversions as well. */
6872 can_convert_arg_bad (tree to, tree from, tree arg)
6877 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6878 p = conversion_obstack_alloc (0);
6879 /* Try to perform the conversion. */
6880 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6882 /* Free all the conversions we allocated. */
6883 obstack_free (&conversion_obstack, p);
6888 /* Convert EXPR to TYPE. Return the converted expression.
6890 Note that we allow bad conversions here because by the time we get to
6891 this point we are committed to doing the conversion. If we end up
6892 doing a bad conversion, convert_like will complain. */
6895 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
6900 if (error_operand_p (expr))
6901 return error_mark_node;
6903 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6904 p = conversion_obstack_alloc (0);
6906 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6911 if (complain & tf_error)
6912 error ("could not convert %qE to %qT", expr, type);
6913 expr = error_mark_node;
6915 else if (processing_template_decl)
6917 /* In a template, we are only concerned about determining the
6918 type of non-dependent expressions, so we do not have to
6919 perform the actual conversion. */
6920 if (TREE_TYPE (expr) != type)
6921 expr = build_nop (type, expr);
6924 expr = convert_like (conv, expr, complain);
6926 /* Free all the conversions we allocated. */
6927 obstack_free (&conversion_obstack, p);
6932 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6933 permitted. If the conversion is valid, the converted expression is
6934 returned. Otherwise, NULL_TREE is returned, except in the case
6935 that TYPE is a class type; in that case, an error is issued. If
6936 C_CAST_P is true, then this direction initialization is taking
6937 place as part of a static_cast being attempted as part of a C-style
6941 perform_direct_initialization_if_possible (tree type,
6944 tsubst_flags_t complain)
6949 if (type == error_mark_node || error_operand_p (expr))
6950 return error_mark_node;
6953 If the destination type is a (possibly cv-qualified) class type:
6955 -- If the initialization is direct-initialization ...,
6956 constructors are considered. ... If no constructor applies, or
6957 the overload resolution is ambiguous, the initialization is
6959 if (CLASS_TYPE_P (type))
6961 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6962 build_tree_list (NULL_TREE, expr),
6963 type, LOOKUP_NORMAL, complain);
6964 return build_cplus_new (type, expr);
6967 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6968 p = conversion_obstack_alloc (0);
6970 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6973 if (!conv || conv->bad_p)
6976 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6977 /*issue_conversion_warnings=*/false,
6979 tf_warning_or_error);
6981 /* Free all the conversions we allocated. */
6982 obstack_free (&conversion_obstack, p);
6987 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6988 is being bound to a temporary. Create and return a new VAR_DECL
6989 with the indicated TYPE; this variable will store the value to
6990 which the reference is bound. */
6993 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6997 /* Create the variable. */
6998 var = create_temporary_var (type);
7000 /* Register the variable. */
7001 if (TREE_STATIC (decl))
7003 /* Namespace-scope or local static; give it a mangled name. */
7006 TREE_STATIC (var) = 1;
7007 name = mangle_ref_init_variable (decl);
7008 DECL_NAME (var) = name;
7009 SET_DECL_ASSEMBLER_NAME (var, name);
7010 var = pushdecl_top_level (var);
7013 /* Create a new cleanup level if necessary. */
7014 maybe_push_cleanup_level (type);
7019 /* EXPR is the initializer for a variable DECL of reference or
7020 std::initializer_list type. Create, push and return a new VAR_DECL
7021 for the initializer so that it will live as long as DECL. Any
7022 cleanup for the new variable is returned through CLEANUP, and the
7023 code to initialize the new variable is returned through INITP. */
7026 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7032 /* Create the temporary variable. */
7033 type = TREE_TYPE (expr);
7034 var = make_temporary_var_for_ref_to_temp (decl, type);
7035 layout_decl (var, 0);
7036 /* If the rvalue is the result of a function call it will be
7037 a TARGET_EXPR. If it is some other construct (such as a
7038 member access expression where the underlying object is
7039 itself the result of a function call), turn it into a
7040 TARGET_EXPR here. It is important that EXPR be a
7041 TARGET_EXPR below since otherwise the INIT_EXPR will
7042 attempt to make a bitwise copy of EXPR to initialize
7044 if (TREE_CODE (expr) != TARGET_EXPR)
7045 expr = get_target_expr (expr);
7046 /* Create the INIT_EXPR that will initialize the temporary
7048 init = build2 (INIT_EXPR, type, var, expr);
7049 if (at_function_scope_p ())
7051 add_decl_expr (var);
7053 if (TREE_STATIC (var))
7054 init = add_stmt_to_compound (init, register_dtor_fn (var));
7056 *cleanup = cxx_maybe_build_cleanup (var);
7058 /* We must be careful to destroy the temporary only
7059 after its initialization has taken place. If the
7060 initialization throws an exception, then the
7061 destructor should not be run. We cannot simply
7062 transform INIT into something like:
7064 (INIT, ({ CLEANUP_STMT; }))
7066 because emit_local_var always treats the
7067 initializer as a full-expression. Thus, the
7068 destructor would run too early; it would run at the
7069 end of initializing the reference variable, rather
7070 than at the end of the block enclosing the
7073 The solution is to pass back a cleanup expression
7074 which the caller is responsible for attaching to
7075 the statement tree. */
7079 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7080 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7081 static_aggregates = tree_cons (NULL_TREE, var,
7089 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7090 initializing a variable of that TYPE. If DECL is non-NULL, it is
7091 the VAR_DECL being initialized with the EXPR. (In that case, the
7092 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7093 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7094 return, if *CLEANUP is no longer NULL, it will be an expression
7095 that should be pushed as a cleanup after the returned expression
7096 is used to initialize DECL.
7098 Return the converted expression. */
7101 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7106 if (type == error_mark_node || error_operand_p (expr))
7107 return error_mark_node;
7109 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7110 p = conversion_obstack_alloc (0);
7112 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7114 if (!conv || conv->bad_p)
7116 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7117 && !real_lvalue_p (expr))
7118 error ("invalid initialization of non-const reference of "
7119 "type %qT from a temporary of type %qT",
7120 type, TREE_TYPE (expr));
7122 error ("invalid initialization of reference of type "
7123 "%qT from expression of type %qT", type,
7125 return error_mark_node;
7128 /* If DECL is non-NULL, then this special rule applies:
7132 The temporary to which the reference is bound or the temporary
7133 that is the complete object to which the reference is bound
7134 persists for the lifetime of the reference.
7136 The temporaries created during the evaluation of the expression
7137 initializing the reference, except the temporary to which the
7138 reference is bound, are destroyed at the end of the
7139 full-expression in which they are created.
7141 In that case, we store the converted expression into a new
7142 VAR_DECL in a new scope.
7144 However, we want to be careful not to create temporaries when
7145 they are not required. For example, given:
7148 struct D : public B {};
7152 there is no need to copy the return value from "f"; we can just
7153 extend its lifetime. Similarly, given:
7156 struct T { operator S(); };
7160 we can extend the lifetime of the return value of the conversion
7162 gcc_assert (conv->kind == ck_ref_bind);
7166 tree base_conv_type;
7168 /* Skip over the REF_BIND. */
7169 conv = conv->u.next;
7170 /* If the next conversion is a BASE_CONV, skip that too -- but
7171 remember that the conversion was required. */
7172 if (conv->kind == ck_base)
7174 base_conv_type = conv->type;
7175 conv = conv->u.next;
7178 base_conv_type = NULL_TREE;
7179 /* Perform the remainder of the conversion. */
7180 expr = convert_like_real (conv, expr,
7181 /*fn=*/NULL_TREE, /*argnum=*/0,
7183 /*issue_conversion_warnings=*/true,
7185 tf_warning_or_error);
7186 if (error_operand_p (expr))
7187 expr = error_mark_node;
7190 if (!real_lvalue_p (expr))
7193 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7194 /* Use its address to initialize the reference variable. */
7195 expr = build_address (var);
7197 expr = convert_to_base (expr,
7198 build_pointer_type (base_conv_type),
7199 /*check_access=*/true,
7201 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7204 /* Take the address of EXPR. */
7205 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7206 /* If a BASE_CONV was required, perform it now. */
7208 expr = (perform_implicit_conversion
7209 (build_pointer_type (base_conv_type), expr,
7210 tf_warning_or_error));
7211 expr = build_nop (type, expr);
7215 /* Perform the conversion. */
7216 expr = convert_like (conv, expr, tf_warning_or_error);
7218 /* Free all the conversions we allocated. */
7219 obstack_free (&conversion_obstack, p);
7224 /* Returns true iff TYPE is some variant of std::initializer_list. */
7227 is_std_init_list (tree type)
7229 return (CLASS_TYPE_P (type)
7230 && CP_TYPE_CONTEXT (type) == std_node
7231 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7234 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7235 will accept an argument list of a single std::initializer_list<T>. */
7238 is_list_ctor (tree decl)
7240 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7243 if (!args || args == void_list_node)
7246 arg = non_reference (TREE_VALUE (args));
7247 if (!is_std_init_list (arg))
7250 args = TREE_CHAIN (args);
7252 if (args && args != void_list_node && !TREE_PURPOSE (args))
7253 /* There are more non-defaulted parms. */
7259 #include "gt-cp-call.h"