1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com) and
6 modified by Brendan Kehoe (brendan@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
25 /* High-level class interface. */
29 #include "coretypes.h"
38 #include "diagnostic.h"
42 #include "langhooks.h"
44 /* The various kinds of conversion. */
46 typedef enum conversion_kind {
62 /* The rank of the conversion. Order of the enumerals matters; better
63 conversions should come earlier in the list. */
65 typedef enum conversion_rank {
76 /* An implicit conversion sequence, in the sense of [over.best.ics].
77 The first conversion to be performed is at the end of the chain.
78 That conversion is always a cr_identity conversion. */
80 typedef struct conversion conversion;
82 /* The kind of conversion represented by this step. */
84 /* The rank of this conversion. */
86 BOOL_BITFIELD user_conv_p : 1;
87 BOOL_BITFIELD ellipsis_p : 1;
88 BOOL_BITFIELD this_p : 1;
89 BOOL_BITFIELD bad_p : 1;
90 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
91 temporary should be created to hold the result of the
93 BOOL_BITFIELD need_temporary_p : 1;
94 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
95 from a pointer-to-derived to pointer-to-base is being performed. */
96 BOOL_BITFIELD base_p : 1;
97 /* If KIND is ck_ref_bind, true when either an lvalue reference is
98 being bound to an lvalue expression or an rvalue reference is
99 being bound to an rvalue expression. */
100 BOOL_BITFIELD rvaluedness_matches_p: 1;
101 BOOL_BITFIELD check_narrowing: 1;
102 /* The type of the expression resulting from the conversion. */
105 /* The next conversion in the chain. Since the conversions are
106 arranged from outermost to innermost, the NEXT conversion will
107 actually be performed before this conversion. This variant is
108 used only when KIND is neither ck_identity nor ck_ambig. */
110 /* The expression at the beginning of the conversion chain. This
111 variant is used only if KIND is ck_identity or ck_ambig. */
113 /* The array of conversions for an initializer_list. */
116 /* The function candidate corresponding to this conversion
117 sequence. This field is only used if KIND is ck_user. */
118 struct z_candidate *cand;
121 #define CONVERSION_RANK(NODE) \
122 ((NODE)->bad_p ? cr_bad \
123 : (NODE)->ellipsis_p ? cr_ellipsis \
124 : (NODE)->user_conv_p ? cr_user \
127 static struct obstack conversion_obstack;
128 static bool conversion_obstack_initialized;
130 static struct z_candidate * tourney (struct z_candidate *);
131 static int equal_functions (tree, tree);
132 static int joust (struct z_candidate *, struct z_candidate *, bool);
133 static int compare_ics (conversion *, conversion *);
134 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
135 static tree build_java_interface_fn_ref (tree, tree);
136 #define convert_like(CONV, EXPR, COMPLAIN) \
137 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
138 /*issue_conversion_warnings=*/true, \
139 /*c_cast_p=*/false, (COMPLAIN))
140 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
141 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
142 /*issue_conversion_warnings=*/true, \
143 /*c_cast_p=*/false, (COMPLAIN))
144 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
145 bool, tsubst_flags_t);
146 static void op_error (enum tree_code, enum tree_code, tree, tree,
148 static VEC(tree,gc) *resolve_args (VEC(tree,gc) *);
149 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
150 static void print_z_candidate (const char *, struct z_candidate *);
151 static void print_z_candidates (struct z_candidate *);
152 static tree build_this (tree);
153 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
154 static bool any_strictly_viable (struct z_candidate *);
155 static struct z_candidate *add_template_candidate
156 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
157 tree, tree, tree, int, unification_kind_t);
158 static struct z_candidate *add_template_candidate_real
159 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
160 tree, tree, tree, int, tree, unification_kind_t);
161 static struct z_candidate *add_template_conv_candidate
162 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
164 static void add_builtin_candidates
165 (struct z_candidate **, enum tree_code, enum tree_code,
167 static void add_builtin_candidate
168 (struct z_candidate **, enum tree_code, enum tree_code,
169 tree, tree, tree, tree *, tree *, int);
170 static bool is_complete (tree);
171 static void build_builtin_candidate
172 (struct z_candidate **, tree, tree, tree, tree *, tree *,
174 static struct z_candidate *add_conv_candidate
175 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
177 static struct z_candidate *add_function_candidate
178 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
180 static conversion *implicit_conversion (tree, tree, tree, bool, int);
181 static conversion *standard_conversion (tree, tree, tree, bool, int);
182 static conversion *reference_binding (tree, tree, tree, bool, int);
183 static conversion *build_conv (conversion_kind, tree, conversion *);
184 static conversion *build_list_conv (tree, tree, int);
185 static bool is_subseq (conversion *, conversion *);
186 static conversion *maybe_handle_ref_bind (conversion **);
187 static void maybe_handle_implicit_object (conversion **);
188 static struct z_candidate *add_candidate
189 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
190 conversion **, tree, tree, int);
191 static tree source_type (conversion *);
192 static void add_warning (struct z_candidate *, struct z_candidate *);
193 static bool reference_related_p (tree, tree);
194 static bool reference_compatible_p (tree, tree);
195 static conversion *convert_class_to_reference (tree, tree, tree, int);
196 static conversion *direct_reference_binding (tree, conversion *);
197 static bool promoted_arithmetic_type_p (tree);
198 static conversion *conditional_conversion (tree, tree);
199 static char *name_as_c_string (tree, tree, bool *);
200 static tree call_builtin_trap (void);
201 static tree prep_operand (tree);
202 static void add_candidates (tree, const VEC(tree,gc) *, tree, bool, tree, tree,
203 int, struct z_candidate **);
204 static conversion *merge_conversion_sequences (conversion *, conversion *);
205 static bool magic_varargs_p (tree);
206 static tree build_temp (tree, tree, int, diagnostic_t *);
208 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
209 NAME can take many forms... */
212 check_dtor_name (tree basetype, tree name)
214 /* Just accept something we've already complained about. */
215 if (name == error_mark_node)
218 if (TREE_CODE (name) == TYPE_DECL)
219 name = TREE_TYPE (name);
220 else if (TYPE_P (name))
222 else if (TREE_CODE (name) == IDENTIFIER_NODE)
224 if ((MAYBE_CLASS_TYPE_P (basetype)
225 && name == constructor_name (basetype))
226 || (TREE_CODE (basetype) == ENUMERAL_TYPE
227 && name == TYPE_IDENTIFIER (basetype)))
230 name = get_type_value (name);
236 template <class T> struct S { ~S(); };
240 NAME will be a class template. */
241 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
245 if (!name || name == error_mark_node)
247 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
250 /* We want the address of a function or method. We avoid creating a
251 pointer-to-member function. */
254 build_addr_func (tree function)
256 tree type = TREE_TYPE (function);
258 /* We have to do these by hand to avoid real pointer to member
260 if (TREE_CODE (type) == METHOD_TYPE)
262 if (TREE_CODE (function) == OFFSET_REF)
264 tree object = build_address (TREE_OPERAND (function, 0));
265 return get_member_function_from_ptrfunc (&object,
266 TREE_OPERAND (function, 1));
268 function = build_address (function);
271 function = decay_conversion (function);
276 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
277 POINTER_TYPE to those. Note, pointer to member function types
278 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
279 two variants. build_call_a is the primitive taking an array of
280 arguments, while build_call_n is a wrapper that handles varargs. */
283 build_call_n (tree function, int n, ...)
286 return build_call_a (function, 0, NULL);
289 tree *argarray = (tree *) alloca (n * sizeof (tree));
294 for (i = 0; i < n; i++)
295 argarray[i] = va_arg (ap, tree);
297 return build_call_a (function, n, argarray);
302 build_call_a (tree function, int n, tree *argarray)
304 int is_constructor = 0;
311 function = build_addr_func (function);
313 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
314 fntype = TREE_TYPE (TREE_TYPE (function));
315 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
316 || TREE_CODE (fntype) == METHOD_TYPE);
317 result_type = TREE_TYPE (fntype);
319 if (TREE_CODE (function) == ADDR_EXPR
320 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
322 decl = TREE_OPERAND (function, 0);
323 if (!TREE_USED (decl))
325 /* We invoke build_call directly for several library
326 functions. These may have been declared normally if
327 we're building libgcc, so we can't just check
329 gcc_assert (DECL_ARTIFICIAL (decl)
330 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
338 /* We check both the decl and the type; a function may be known not to
339 throw without being declared throw(). */
340 nothrow = ((decl && TREE_NOTHROW (decl))
341 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
343 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
344 current_function_returns_abnormally = 1;
346 if (decl && TREE_DEPRECATED (decl))
347 warn_deprecated_use (decl, NULL_TREE);
348 require_complete_eh_spec_types (fntype, decl);
350 if (decl && DECL_CONSTRUCTOR_P (decl))
353 /* Don't pass empty class objects by value. This is useful
354 for tags in STL, which are used to control overload resolution.
355 We don't need to handle other cases of copying empty classes. */
356 if (! decl || ! DECL_BUILT_IN (decl))
357 for (i = 0; i < n; i++)
358 if (is_empty_class (TREE_TYPE (argarray[i]))
359 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
361 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
362 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
366 function = build_call_array (result_type, function, n, argarray);
367 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
368 TREE_NOTHROW (function) = nothrow;
373 /* Build something of the form ptr->method (args)
374 or object.method (args). This can also build
375 calls to constructors, and find friends.
377 Member functions always take their class variable
380 INSTANCE is a class instance.
382 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
384 PARMS help to figure out what that NAME really refers to.
386 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
387 down to the real instance type to use for access checking. We need this
388 information to get protected accesses correct.
390 FLAGS is the logical disjunction of zero or more LOOKUP_
391 flags. See cp-tree.h for more info.
393 If this is all OK, calls build_function_call with the resolved
396 This function must also handle being called to perform
397 initialization, promotion/coercion of arguments, and
398 instantiation of default parameters.
400 Note that NAME may refer to an instance variable name. If
401 `operator()()' is defined for the type of that field, then we return
404 /* New overloading code. */
406 typedef struct z_candidate z_candidate;
408 typedef struct candidate_warning candidate_warning;
409 struct candidate_warning {
411 candidate_warning *next;
415 /* The FUNCTION_DECL that will be called if this candidate is
416 selected by overload resolution. */
418 /* If not NULL_TREE, the first argument to use when calling this
421 /* The rest of the arguments to use when calling this function. If
422 there are no further arguments this may be NULL or it may be an
424 const VEC(tree,gc) *args;
425 /* The implicit conversion sequences for each of the arguments to
428 /* The number of implicit conversion sequences. */
430 /* If FN is a user-defined conversion, the standard conversion
431 sequence from the type returned by FN to the desired destination
433 conversion *second_conv;
435 /* If FN is a member function, the binfo indicating the path used to
436 qualify the name of FN at the call site. This path is used to
437 determine whether or not FN is accessible if it is selected by
438 overload resolution. The DECL_CONTEXT of FN will always be a
439 (possibly improper) base of this binfo. */
441 /* If FN is a non-static member function, the binfo indicating the
442 subobject to which the `this' pointer should be converted if FN
443 is selected by overload resolution. The type pointed to the by
444 the `this' pointer must correspond to the most derived class
445 indicated by the CONVERSION_PATH. */
446 tree conversion_path;
448 candidate_warning *warnings;
452 /* Returns true iff T is a null pointer constant in the sense of
456 null_ptr_cst_p (tree t)
460 A null pointer constant is an integral constant expression
461 (_expr.const_) rvalue of integer type that evaluates to zero. */
462 t = integral_constant_value (t);
465 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
468 if (!TREE_OVERFLOW (t))
474 /* Returns nonzero if PARMLIST consists of only default parms and/or
478 sufficient_parms_p (const_tree parmlist)
480 for (; parmlist && parmlist != void_list_node;
481 parmlist = TREE_CHAIN (parmlist))
482 if (!TREE_PURPOSE (parmlist))
487 /* Allocate N bytes of memory from the conversion obstack. The memory
488 is zeroed before being returned. */
491 conversion_obstack_alloc (size_t n)
494 if (!conversion_obstack_initialized)
496 gcc_obstack_init (&conversion_obstack);
497 conversion_obstack_initialized = true;
499 p = obstack_alloc (&conversion_obstack, n);
504 /* Dynamically allocate a conversion. */
507 alloc_conversion (conversion_kind kind)
510 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
515 #ifdef ENABLE_CHECKING
517 /* Make sure that all memory on the conversion obstack has been
521 validate_conversion_obstack (void)
523 if (conversion_obstack_initialized)
524 gcc_assert ((obstack_next_free (&conversion_obstack)
525 == obstack_base (&conversion_obstack)));
528 #endif /* ENABLE_CHECKING */
530 /* Dynamically allocate an array of N conversions. */
533 alloc_conversions (size_t n)
535 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
539 build_conv (conversion_kind code, tree type, conversion *from)
542 conversion_rank rank = CONVERSION_RANK (from);
544 /* Note that the caller is responsible for filling in t->cand for
545 user-defined conversions. */
546 t = alloc_conversion (code);
569 t->user_conv_p = (code == ck_user || from->user_conv_p);
570 t->bad_p = from->bad_p;
575 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
576 specialization of std::initializer_list<T>, if such a conversion is
580 build_list_conv (tree type, tree ctor, int flags)
582 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
583 unsigned len = CONSTRUCTOR_NELTS (ctor);
584 conversion **subconvs = alloc_conversions (len);
589 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
592 = implicit_conversion (elttype, TREE_TYPE (val), val,
600 t = alloc_conversion (ck_list);
602 t->u.list = subconvs;
605 for (i = 0; i < len; ++i)
607 conversion *sub = subconvs[i];
608 if (sub->rank > t->rank)
610 if (sub->user_conv_p)
611 t->user_conv_p = true;
619 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
620 aggregate class, if such a conversion is possible. */
623 build_aggr_conv (tree type, tree ctor, int flags)
625 unsigned HOST_WIDE_INT i = 0;
627 tree field = TYPE_FIELDS (type);
629 for (; field; field = TREE_CHAIN (field), ++i)
631 if (TREE_CODE (field) != FIELD_DECL)
633 if (i < CONSTRUCTOR_NELTS (ctor))
635 constructor_elt *ce = CONSTRUCTOR_ELT (ctor, i);
636 if (!can_convert_arg (TREE_TYPE (field), TREE_TYPE (ce->value),
640 else if (build_value_init (TREE_TYPE (field)) == error_mark_node)
644 c = alloc_conversion (ck_aggr);
647 c->user_conv_p = true;
652 /* Build a representation of the identity conversion from EXPR to
653 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
656 build_identity_conv (tree type, tree expr)
660 c = alloc_conversion (ck_identity);
667 /* Converting from EXPR to TYPE was ambiguous in the sense that there
668 were multiple user-defined conversions to accomplish the job.
669 Build a conversion that indicates that ambiguity. */
672 build_ambiguous_conv (tree type, tree expr)
676 c = alloc_conversion (ck_ambig);
684 strip_top_quals (tree t)
686 if (TREE_CODE (t) == ARRAY_TYPE)
688 return cp_build_qualified_type (t, 0);
691 /* Returns the standard conversion path (see [conv]) from type FROM to type
692 TO, if any. For proper handling of null pointer constants, you must
693 also pass the expression EXPR to convert from. If C_CAST_P is true,
694 this conversion is coming from a C-style cast. */
697 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
700 enum tree_code fcode, tcode;
702 bool fromref = false;
704 to = non_reference (to);
705 if (TREE_CODE (from) == REFERENCE_TYPE)
708 from = TREE_TYPE (from);
710 to = strip_top_quals (to);
711 from = strip_top_quals (from);
713 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
714 && expr && type_unknown_p (expr))
716 tsubst_flags_t tflags = tf_conv;
717 if (!(flags & LOOKUP_PROTECT))
718 tflags |= tf_no_access_control;
719 expr = instantiate_type (to, expr, tflags);
720 if (expr == error_mark_node)
722 from = TREE_TYPE (expr);
725 fcode = TREE_CODE (from);
726 tcode = TREE_CODE (to);
728 conv = build_identity_conv (from, expr);
729 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
731 from = type_decays_to (from);
732 fcode = TREE_CODE (from);
733 conv = build_conv (ck_lvalue, from, conv);
735 else if (fromref || (expr && lvalue_p (expr)))
740 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
743 from = strip_top_quals (bitfield_type);
744 fcode = TREE_CODE (from);
747 conv = build_conv (ck_rvalue, from, conv);
750 /* Allow conversion between `__complex__' data types. */
751 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
753 /* The standard conversion sequence to convert FROM to TO is
754 the standard conversion sequence to perform componentwise
756 conversion *part_conv = standard_conversion
757 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
761 conv = build_conv (part_conv->kind, to, conv);
762 conv->rank = part_conv->rank;
770 if (same_type_p (from, to))
773 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
774 && expr && null_ptr_cst_p (expr))
775 conv = build_conv (ck_std, to, conv);
776 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
777 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
779 /* For backwards brain damage compatibility, allow interconversion of
780 pointers and integers with a pedwarn. */
781 conv = build_conv (ck_std, to, conv);
784 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
786 /* For backwards brain damage compatibility, allow interconversion of
787 enums and integers with a pedwarn. */
788 conv = build_conv (ck_std, to, conv);
791 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
792 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
797 if (tcode == POINTER_TYPE
798 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
801 else if (VOID_TYPE_P (TREE_TYPE (to))
802 && !TYPE_PTRMEM_P (from)
803 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
805 from = build_pointer_type
806 (cp_build_qualified_type (void_type_node,
807 cp_type_quals (TREE_TYPE (from))));
808 conv = build_conv (ck_ptr, from, conv);
810 else if (TYPE_PTRMEM_P (from))
812 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
813 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
815 if (DERIVED_FROM_P (fbase, tbase)
816 && (same_type_ignoring_top_level_qualifiers_p
817 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
818 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
820 from = build_ptrmem_type (tbase,
821 TYPE_PTRMEM_POINTED_TO_TYPE (from));
822 conv = build_conv (ck_pmem, from, conv);
824 else if (!same_type_p (fbase, tbase))
827 else if (CLASS_TYPE_P (TREE_TYPE (from))
828 && CLASS_TYPE_P (TREE_TYPE (to))
831 An rvalue of type "pointer to cv D," where D is a
832 class type, can be converted to an rvalue of type
833 "pointer to cv B," where B is a base class (clause
834 _class.derived_) of D. If B is an inaccessible
835 (clause _class.access_) or ambiguous
836 (_class.member.lookup_) base class of D, a program
837 that necessitates this conversion is ill-formed.
838 Therefore, we use DERIVED_FROM_P, and do not check
839 access or uniqueness. */
840 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
843 cp_build_qualified_type (TREE_TYPE (to),
844 cp_type_quals (TREE_TYPE (from)));
845 from = build_pointer_type (from);
846 conv = build_conv (ck_ptr, from, conv);
850 if (tcode == POINTER_TYPE)
852 to_pointee = TREE_TYPE (to);
853 from_pointee = TREE_TYPE (from);
857 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
858 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
861 if (same_type_p (from, to))
863 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
864 /* In a C-style cast, we ignore CV-qualification because we
865 are allowed to perform a static_cast followed by a
867 conv = build_conv (ck_qual, to, conv);
868 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
869 conv = build_conv (ck_qual, to, conv);
870 else if (expr && string_conv_p (to, expr, 0))
871 /* converting from string constant to char *. */
872 conv = build_conv (ck_qual, to, conv);
873 else if (ptr_reasonably_similar (to_pointee, from_pointee))
875 conv = build_conv (ck_ptr, to, conv);
883 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
885 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
886 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
887 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
888 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
890 if (!DERIVED_FROM_P (fbase, tbase)
891 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
892 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
893 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
894 || cp_type_quals (fbase) != cp_type_quals (tbase))
897 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
898 from = build_method_type_directly (from,
900 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
901 from = build_ptrmemfunc_type (build_pointer_type (from));
902 conv = build_conv (ck_pmem, from, conv);
905 else if (tcode == BOOLEAN_TYPE)
909 An rvalue of arithmetic, unscoped enumeration, pointer, or
910 pointer to member type can be converted to an rvalue of type
912 if (ARITHMETIC_TYPE_P (from)
913 || UNSCOPED_ENUM_P (from)
914 || fcode == POINTER_TYPE
915 || TYPE_PTR_TO_MEMBER_P (from))
917 conv = build_conv (ck_std, to, conv);
918 if (fcode == POINTER_TYPE
919 || TYPE_PTRMEM_P (from)
920 || (TYPE_PTRMEMFUNC_P (from)
921 && conv->rank < cr_pbool))
922 conv->rank = cr_pbool;
928 /* We don't check for ENUMERAL_TYPE here because there are no standard
929 conversions to enum type. */
930 /* As an extension, allow conversion to complex type. */
931 else if (ARITHMETIC_TYPE_P (to))
933 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
934 || SCOPED_ENUM_P (from))
936 conv = build_conv (ck_std, to, conv);
938 /* Give this a better rank if it's a promotion. */
939 if (same_type_p (to, type_promotes_to (from))
940 && conv->u.next->rank <= cr_promotion)
941 conv->rank = cr_promotion;
943 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
944 && vector_types_convertible_p (from, to, false))
945 return build_conv (ck_std, to, conv);
946 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
947 && is_properly_derived_from (from, to))
949 if (conv->kind == ck_rvalue)
951 conv = build_conv (ck_base, to, conv);
952 /* The derived-to-base conversion indicates the initialization
953 of a parameter with base type from an object of a derived
954 type. A temporary object is created to hold the result of
955 the conversion unless we're binding directly to a reference. */
956 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
961 if (flags & LOOKUP_NO_NARROWING)
962 conv->check_narrowing = true;
967 /* Returns nonzero if T1 is reference-related to T2. */
970 reference_related_p (tree t1, tree t2)
972 t1 = TYPE_MAIN_VARIANT (t1);
973 t2 = TYPE_MAIN_VARIANT (t2);
977 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
978 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
980 return (same_type_p (t1, t2)
981 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
982 && DERIVED_FROM_P (t1, t2)));
985 /* Returns nonzero if T1 is reference-compatible with T2. */
988 reference_compatible_p (tree t1, tree t2)
992 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
993 reference-related to T2 and cv1 is the same cv-qualification as,
994 or greater cv-qualification than, cv2. */
995 return (reference_related_p (t1, t2)
996 && at_least_as_qualified_p (t1, t2));
999 /* Determine whether or not the EXPR (of class type S) can be
1000 converted to T as in [over.match.ref]. */
1003 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1009 struct z_candidate *candidates;
1010 struct z_candidate *cand;
1013 conversions = lookup_conversions (s);
1019 Assuming that "cv1 T" is the underlying type of the reference
1020 being initialized, and "cv S" is the type of the initializer
1021 expression, with S a class type, the candidate functions are
1022 selected as follows:
1024 --The conversion functions of S and its base classes are
1025 considered. Those that are not hidden within S and yield type
1026 "reference to cv2 T2", where "cv1 T" is reference-compatible
1027 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1029 The argument list has one argument, which is the initializer
1034 /* Conceptually, we should take the address of EXPR and put it in
1035 the argument list. Unfortunately, however, that can result in
1036 error messages, which we should not issue now because we are just
1037 trying to find a conversion operator. Therefore, we use NULL,
1038 cast to the appropriate type. */
1039 first_arg = build_int_cst (build_pointer_type (s), 0);
1041 t = TREE_TYPE (reference_type);
1043 for (; conversions; conversions = TREE_CHAIN (conversions))
1045 tree fns = TREE_VALUE (conversions);
1047 for (; fns; fns = OVL_NEXT (fns))
1049 tree f = OVL_CURRENT (fns);
1050 tree t2 = TREE_TYPE (TREE_TYPE (f));
1052 if (DECL_NONCONVERTING_P (f)
1053 && (flags & LOOKUP_ONLYCONVERTING))
1058 /* If this is a template function, try to get an exact
1060 if (TREE_CODE (f) == TEMPLATE_DECL)
1062 cand = add_template_candidate (&candidates,
1069 TREE_PURPOSE (conversions),
1075 /* Now, see if the conversion function really returns
1076 an lvalue of the appropriate type. From the
1077 point of view of unification, simply returning an
1078 rvalue of the right type is good enough. */
1080 t2 = TREE_TYPE (TREE_TYPE (f));
1081 if (TREE_CODE (t2) != REFERENCE_TYPE
1082 || !reference_compatible_p (t, TREE_TYPE (t2)))
1084 candidates = candidates->next;
1089 else if (TREE_CODE (t2) == REFERENCE_TYPE
1090 && reference_compatible_p (t, TREE_TYPE (t2)))
1091 cand = add_function_candidate (&candidates, f, s, first_arg,
1092 NULL, TYPE_BINFO (s),
1093 TREE_PURPOSE (conversions),
1098 conversion *identity_conv;
1099 /* Build a standard conversion sequence indicating the
1100 binding from the reference type returned by the
1101 function to the desired REFERENCE_TYPE. */
1103 = build_identity_conv (TREE_TYPE (TREE_TYPE
1104 (TREE_TYPE (cand->fn))),
1107 = (direct_reference_binding
1108 (reference_type, identity_conv));
1109 cand->second_conv->rvaluedness_matches_p
1110 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1111 == TYPE_REF_IS_RVALUE (reference_type);
1112 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1117 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1118 /* If none of the conversion functions worked out, let our caller
1123 cand = tourney (candidates);
1127 /* Now that we know that this is the function we're going to use fix
1128 the dummy first argument. */
1129 gcc_assert (cand->first_arg == NULL_TREE
1130 || integer_zerop (cand->first_arg));
1131 cand->first_arg = build_this (expr);
1133 /* Build a user-defined conversion sequence representing the
1135 conv = build_conv (ck_user,
1136 TREE_TYPE (TREE_TYPE (cand->fn)),
1137 build_identity_conv (TREE_TYPE (expr), expr));
1140 /* Merge it with the standard conversion sequence from the
1141 conversion function's return type to the desired type. */
1142 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1144 if (cand->viable == -1)
1147 return cand->second_conv;
1150 /* A reference of the indicated TYPE is being bound directly to the
1151 expression represented by the implicit conversion sequence CONV.
1152 Return a conversion sequence for this binding. */
1155 direct_reference_binding (tree type, conversion *conv)
1159 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1160 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1162 t = TREE_TYPE (type);
1166 When a parameter of reference type binds directly
1167 (_dcl.init.ref_) to an argument expression, the implicit
1168 conversion sequence is the identity conversion, unless the
1169 argument expression has a type that is a derived class of the
1170 parameter type, in which case the implicit conversion sequence is
1171 a derived-to-base Conversion.
1173 If the parameter binds directly to the result of applying a
1174 conversion function to the argument expression, the implicit
1175 conversion sequence is a user-defined conversion sequence
1176 (_over.ics.user_), with the second standard conversion sequence
1177 either an identity conversion or, if the conversion function
1178 returns an entity of a type that is a derived class of the
1179 parameter type, a derived-to-base conversion. */
1180 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1182 /* Represent the derived-to-base conversion. */
1183 conv = build_conv (ck_base, t, conv);
1184 /* We will actually be binding to the base-class subobject in
1185 the derived class, so we mark this conversion appropriately.
1186 That way, convert_like knows not to generate a temporary. */
1187 conv->need_temporary_p = false;
1189 return build_conv (ck_ref_bind, type, conv);
1192 /* Returns the conversion path from type FROM to reference type TO for
1193 purposes of reference binding. For lvalue binding, either pass a
1194 reference type to FROM or an lvalue expression to EXPR. If the
1195 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1196 the conversion returned. If C_CAST_P is true, this
1197 conversion is coming from a C-style cast. */
1200 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1202 conversion *conv = NULL;
1203 tree to = TREE_TYPE (rto);
1208 cp_lvalue_kind lvalue_p = clk_none;
1210 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1212 expr = instantiate_type (to, expr, tf_none);
1213 if (expr == error_mark_node)
1215 from = TREE_TYPE (expr);
1218 if (TREE_CODE (from) == REFERENCE_TYPE)
1220 /* Anything with reference type is an lvalue. */
1221 lvalue_p = clk_ordinary;
1222 from = TREE_TYPE (from);
1225 lvalue_p = real_lvalue_p (expr);
1228 if ((lvalue_p & clk_bitfield) != 0)
1229 tfrom = unlowered_expr_type (expr);
1231 /* Figure out whether or not the types are reference-related and
1232 reference compatible. We have do do this after stripping
1233 references from FROM. */
1234 related_p = reference_related_p (to, tfrom);
1235 /* If this is a C cast, first convert to an appropriately qualified
1236 type, so that we can later do a const_cast to the desired type. */
1237 if (related_p && c_cast_p
1238 && !at_least_as_qualified_p (to, tfrom))
1239 to = build_qualified_type (to, cp_type_quals (tfrom));
1240 compatible_p = reference_compatible_p (to, tfrom);
1242 /* Directly bind reference when target expression's type is compatible with
1243 the reference and expression is an lvalue. In DR391, the wording in
1244 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1245 const and rvalue references to rvalues of compatible class type. */
1248 || (!(flags & LOOKUP_NO_TEMP_BIND)
1249 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1250 && CLASS_TYPE_P (from))))
1254 If the initializer expression
1256 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1257 is reference-compatible with "cv2 T2,"
1259 the reference is bound directly to the initializer expression
1263 If the initializer expression is an rvalue, with T2 a class type,
1264 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1265 is bound to the object represented by the rvalue or to a sub-object
1266 within that object. */
1268 conv = build_identity_conv (tfrom, expr);
1269 conv = direct_reference_binding (rto, conv);
1271 if (flags & LOOKUP_PREFER_RVALUE)
1272 /* The top-level caller requested that we pretend that the lvalue
1273 be treated as an rvalue. */
1274 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1276 conv->rvaluedness_matches_p
1277 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1279 if ((lvalue_p & clk_bitfield) != 0
1280 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1281 /* For the purposes of overload resolution, we ignore the fact
1282 this expression is a bitfield or packed field. (In particular,
1283 [over.ics.ref] says specifically that a function with a
1284 non-const reference parameter is viable even if the
1285 argument is a bitfield.)
1287 However, when we actually call the function we must create
1288 a temporary to which to bind the reference. If the
1289 reference is volatile, or isn't const, then we cannot make
1290 a temporary, so we just issue an error when the conversion
1292 conv->need_temporary_p = true;
1296 /* [class.conv.fct] A conversion function is never used to convert a
1297 (possibly cv-qualified) object to the (possibly cv-qualified) same
1298 object type (or a reference to it), to a (possibly cv-qualified) base
1299 class of that type (or a reference to it).... */
1300 else if (CLASS_TYPE_P (from) && !related_p
1301 && !(flags & LOOKUP_NO_CONVERSION))
1305 If the initializer expression
1307 -- has a class type (i.e., T2 is a class type) can be
1308 implicitly converted to an lvalue of type "cv3 T3," where
1309 "cv1 T1" is reference-compatible with "cv3 T3". (this
1310 conversion is selected by enumerating the applicable
1311 conversion functions (_over.match.ref_) and choosing the
1312 best one through overload resolution. (_over.match_).
1314 the reference is bound to the lvalue result of the conversion
1315 in the second case. */
1316 conv = convert_class_to_reference (rto, from, expr, flags);
1321 /* From this point on, we conceptually need temporaries, even if we
1322 elide them. Only the cases above are "direct bindings". */
1323 if (flags & LOOKUP_NO_TEMP_BIND)
1328 When a parameter of reference type is not bound directly to an
1329 argument expression, the conversion sequence is the one required
1330 to convert the argument expression to the underlying type of the
1331 reference according to _over.best.ics_. Conceptually, this
1332 conversion sequence corresponds to copy-initializing a temporary
1333 of the underlying type with the argument expression. Any
1334 difference in top-level cv-qualification is subsumed by the
1335 initialization itself and does not constitute a conversion. */
1339 Otherwise, the reference shall be to a non-volatile const type.
1341 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1342 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1347 Otherwise, a temporary of type "cv1 T1" is created and
1348 initialized from the initializer expression using the rules for a
1349 non-reference copy initialization. If T1 is reference-related to
1350 T2, cv1 must be the same cv-qualification as, or greater
1351 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1352 if (related_p && !at_least_as_qualified_p (to, from))
1355 /* We're generating a temporary now, but don't bind any more in the
1356 conversion (specifically, don't slice the temporary returned by a
1357 conversion operator). */
1358 flags |= LOOKUP_NO_TEMP_BIND;
1360 /* Temporaries are copy-initialized, except for this hack to allow
1361 explicit conversion ops to the copy ctor. See also
1362 add_function_candidate. */
1363 if (!(flags & LOOKUP_COPY_PARM))
1364 flags |= LOOKUP_ONLYCONVERTING;
1366 conv = implicit_conversion (to, from, expr, c_cast_p,
1371 conv = build_conv (ck_ref_bind, rto, conv);
1372 /* This reference binding, unlike those above, requires the
1373 creation of a temporary. */
1374 conv->need_temporary_p = true;
1375 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1380 /* Returns the implicit conversion sequence (see [over.ics]) from type
1381 FROM to type TO. The optional expression EXPR may affect the
1382 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1383 true, this conversion is coming from a C-style cast. */
1386 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1391 if (from == error_mark_node || to == error_mark_node
1392 || expr == error_mark_node)
1395 if (TREE_CODE (to) == REFERENCE_TYPE)
1396 conv = reference_binding (to, from, expr, c_cast_p, flags);
1398 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1403 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1405 if (is_std_init_list (to))
1406 return build_list_conv (to, expr, flags);
1408 /* Allow conversion from an initializer-list with one element to a
1410 if (SCALAR_TYPE_P (to))
1412 int nelts = CONSTRUCTOR_NELTS (expr);
1416 elt = integer_zero_node;
1417 else if (nelts == 1)
1418 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1420 elt = error_mark_node;
1422 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1426 conv->check_narrowing = true;
1427 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1428 /* Too many levels of braces, i.e. '{{1}}'. */
1435 if (expr != NULL_TREE
1436 && (MAYBE_CLASS_TYPE_P (from)
1437 || MAYBE_CLASS_TYPE_P (to))
1438 && (flags & LOOKUP_NO_CONVERSION) == 0)
1440 struct z_candidate *cand;
1441 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING));
1443 if (CLASS_TYPE_P (to)
1444 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1445 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1446 return build_aggr_conv (to, expr, flags);
1448 cand = build_user_type_conversion_1 (to, expr, convflags);
1450 conv = cand->second_conv;
1452 /* We used to try to bind a reference to a temporary here, but that
1453 is now handled after the recursive call to this function at the end
1454 of reference_binding. */
1461 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1462 functions. ARGS will not be changed until a single candidate is
1465 static struct z_candidate *
1466 add_candidate (struct z_candidate **candidates,
1467 tree fn, tree first_arg, const VEC(tree,gc) *args,
1468 size_t num_convs, conversion **convs,
1469 tree access_path, tree conversion_path,
1472 struct z_candidate *cand = (struct z_candidate *)
1473 conversion_obstack_alloc (sizeof (struct z_candidate));
1476 cand->first_arg = first_arg;
1478 cand->convs = convs;
1479 cand->num_convs = num_convs;
1480 cand->access_path = access_path;
1481 cand->conversion_path = conversion_path;
1482 cand->viable = viable;
1483 cand->next = *candidates;
1489 /* Create an overload candidate for the function or method FN called
1490 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1491 FLAGS is passed on to implicit_conversion.
1493 This does not change ARGS.
1495 CTYPE, if non-NULL, is the type we want to pretend this function
1496 comes from for purposes of overload resolution. */
1498 static struct z_candidate *
1499 add_function_candidate (struct z_candidate **candidates,
1500 tree fn, tree ctype, tree first_arg,
1501 const VEC(tree,gc) *args, tree access_path,
1502 tree conversion_path, int flags)
1504 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1508 tree orig_first_arg = first_arg;
1512 /* At this point we should not see any functions which haven't been
1513 explicitly declared, except for friend functions which will have
1514 been found using argument dependent lookup. */
1515 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1517 /* The `this', `in_chrg' and VTT arguments to constructors are not
1518 considered in overload resolution. */
1519 if (DECL_CONSTRUCTOR_P (fn))
1521 parmlist = skip_artificial_parms_for (fn, parmlist);
1522 skip = num_artificial_parms_for (fn);
1523 if (skip > 0 && first_arg != NULL_TREE)
1526 first_arg = NULL_TREE;
1532 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1533 convs = alloc_conversions (len);
1535 /* 13.3.2 - Viable functions [over.match.viable]
1536 First, to be a viable function, a candidate function shall have enough
1537 parameters to agree in number with the arguments in the list.
1539 We need to check this first; otherwise, checking the ICSes might cause
1540 us to produce an ill-formed template instantiation. */
1542 parmnode = parmlist;
1543 for (i = 0; i < len; ++i)
1545 if (parmnode == NULL_TREE || parmnode == void_list_node)
1547 parmnode = TREE_CHAIN (parmnode);
1550 if (i < len && parmnode)
1553 /* Make sure there are default args for the rest of the parms. */
1554 else if (!sufficient_parms_p (parmnode))
1560 /* Second, for F to be a viable function, there shall exist for each
1561 argument an implicit conversion sequence that converts that argument
1562 to the corresponding parameter of F. */
1564 parmnode = parmlist;
1566 for (i = 0; i < len; ++i)
1572 if (parmnode == void_list_node)
1575 if (i == 0 && first_arg != NULL_TREE)
1578 arg = VEC_index (tree, args,
1579 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1580 argtype = lvalue_type (arg);
1582 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1583 && ! DECL_CONSTRUCTOR_P (fn));
1587 tree parmtype = TREE_VALUE (parmnode);
1590 /* The type of the implicit object parameter ('this') for
1591 overload resolution is not always the same as for the
1592 function itself; conversion functions are considered to
1593 be members of the class being converted, and functions
1594 introduced by a using-declaration are considered to be
1595 members of the class that uses them.
1597 Since build_over_call ignores the ICS for the `this'
1598 parameter, we can just change the parm type. */
1599 if (ctype && is_this)
1602 = build_qualified_type (ctype,
1603 TYPE_QUALS (TREE_TYPE (parmtype)));
1604 parmtype = build_pointer_type (parmtype);
1607 if (ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1609 /* Hack: Direct-initialize copy parm (i.e. suppress
1610 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1611 work. See also reference_binding. */
1612 lflags |= LOOKUP_COPY_PARM;
1613 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1614 lflags |= LOOKUP_NO_CONVERSION;
1617 lflags |= LOOKUP_ONLYCONVERTING;
1619 t = implicit_conversion (parmtype, argtype, arg,
1620 /*c_cast_p=*/false, lflags);
1624 t = build_identity_conv (argtype, arg);
1625 t->ellipsis_p = true;
1642 parmnode = TREE_CHAIN (parmnode);
1646 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1647 access_path, conversion_path, viable);
1650 /* Create an overload candidate for the conversion function FN which will
1651 be invoked for expression OBJ, producing a pointer-to-function which
1652 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1653 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1654 passed on to implicit_conversion.
1656 Actually, we don't really care about FN; we care about the type it
1657 converts to. There may be multiple conversion functions that will
1658 convert to that type, and we rely on build_user_type_conversion_1 to
1659 choose the best one; so when we create our candidate, we record the type
1660 instead of the function. */
1662 static struct z_candidate *
1663 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1664 tree first_arg, const VEC(tree,gc) *arglist,
1665 tree access_path, tree conversion_path)
1667 tree totype = TREE_TYPE (TREE_TYPE (fn));
1668 int i, len, viable, flags;
1669 tree parmlist, parmnode;
1672 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1673 parmlist = TREE_TYPE (parmlist);
1674 parmlist = TYPE_ARG_TYPES (parmlist);
1676 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1677 convs = alloc_conversions (len);
1678 parmnode = parmlist;
1680 flags = LOOKUP_IMPLICIT;
1682 /* Don't bother looking up the same type twice. */
1683 if (*candidates && (*candidates)->fn == totype)
1686 for (i = 0; i < len; ++i)
1693 else if (i == 1 && first_arg != NULL_TREE)
1696 arg = VEC_index (tree, arglist,
1697 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1698 argtype = lvalue_type (arg);
1701 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1703 else if (parmnode == void_list_node)
1706 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1707 /*c_cast_p=*/false, flags);
1710 t = build_identity_conv (argtype, arg);
1711 t->ellipsis_p = true;
1725 parmnode = TREE_CHAIN (parmnode);
1731 if (!sufficient_parms_p (parmnode))
1734 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1735 access_path, conversion_path, viable);
1739 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1740 tree type1, tree type2, tree *args, tree *argtypes,
1752 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1753 convs = alloc_conversions (num_convs);
1754 flags |= LOOKUP_ONLYCONVERTING;
1756 for (i = 0; i < 2; ++i)
1761 t = implicit_conversion (types[i], argtypes[i], args[i],
1762 /*c_cast_p=*/false, flags);
1766 /* We need something for printing the candidate. */
1767 t = build_identity_conv (types[i], NULL_TREE);
1774 /* For COND_EXPR we rearranged the arguments; undo that now. */
1777 convs[2] = convs[1];
1778 convs[1] = convs[0];
1779 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1780 /*c_cast_p=*/false, flags);
1787 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1789 /*access_path=*/NULL_TREE,
1790 /*conversion_path=*/NULL_TREE,
1795 is_complete (tree t)
1797 return COMPLETE_TYPE_P (complete_type (t));
1800 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1803 promoted_arithmetic_type_p (tree type)
1807 In this section, the term promoted integral type is used to refer
1808 to those integral types which are preserved by integral promotion
1809 (including e.g. int and long but excluding e.g. char).
1810 Similarly, the term promoted arithmetic type refers to promoted
1811 integral types plus floating types. */
1812 return ((CP_INTEGRAL_TYPE_P (type)
1813 && same_type_p (type_promotes_to (type), type))
1814 || TREE_CODE (type) == REAL_TYPE);
1817 /* Create any builtin operator overload candidates for the operator in
1818 question given the converted operand types TYPE1 and TYPE2. The other
1819 args are passed through from add_builtin_candidates to
1820 build_builtin_candidate.
1822 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1823 If CODE is requires candidates operands of the same type of the kind
1824 of which TYPE1 and TYPE2 are, we add both candidates
1825 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1828 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1829 enum tree_code code2, tree fnname, tree type1,
1830 tree type2, tree *args, tree *argtypes, int flags)
1834 case POSTINCREMENT_EXPR:
1835 case POSTDECREMENT_EXPR:
1836 args[1] = integer_zero_node;
1837 type2 = integer_type_node;
1846 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1847 and VQ is either volatile or empty, there exist candidate operator
1848 functions of the form
1849 VQ T& operator++(VQ T&);
1850 T operator++(VQ T&, int);
1851 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1852 type other than bool, and VQ is either volatile or empty, there exist
1853 candidate operator functions of the form
1854 VQ T& operator--(VQ T&);
1855 T operator--(VQ T&, int);
1856 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1857 complete object type, and VQ is either volatile or empty, there exist
1858 candidate operator functions of the form
1859 T*VQ& operator++(T*VQ&);
1860 T*VQ& operator--(T*VQ&);
1861 T* operator++(T*VQ&, int);
1862 T* operator--(T*VQ&, int); */
1864 case POSTDECREMENT_EXPR:
1865 case PREDECREMENT_EXPR:
1866 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1868 case POSTINCREMENT_EXPR:
1869 case PREINCREMENT_EXPR:
1870 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1872 type1 = build_reference_type (type1);
1877 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1878 exist candidate operator functions of the form
1882 8 For every function type T, there exist candidate operator functions of
1884 T& operator*(T*); */
1887 if (TREE_CODE (type1) == POINTER_TYPE
1888 && (TYPE_PTROB_P (type1)
1889 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1893 /* 9 For every type T, there exist candidate operator functions of the form
1896 10For every promoted arithmetic type T, there exist candidate operator
1897 functions of the form
1901 case UNARY_PLUS_EXPR: /* unary + */
1902 if (TREE_CODE (type1) == POINTER_TYPE)
1905 if (ARITHMETIC_TYPE_P (type1))
1909 /* 11For every promoted integral type T, there exist candidate operator
1910 functions of the form
1914 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1918 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1919 is the same type as C2 or is a derived class of C2, T is a complete
1920 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1921 there exist candidate operator functions of the form
1922 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1923 where CV12 is the union of CV1 and CV2. */
1926 if (TREE_CODE (type1) == POINTER_TYPE
1927 && TYPE_PTR_TO_MEMBER_P (type2))
1929 tree c1 = TREE_TYPE (type1);
1930 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1932 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1933 && (TYPE_PTRMEMFUNC_P (type2)
1934 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1939 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1940 didate operator functions of the form
1945 bool operator<(L, R);
1946 bool operator>(L, R);
1947 bool operator<=(L, R);
1948 bool operator>=(L, R);
1949 bool operator==(L, R);
1950 bool operator!=(L, R);
1951 where LR is the result of the usual arithmetic conversions between
1954 14For every pair of types T and I, where T is a cv-qualified or cv-
1955 unqualified complete object type and I is a promoted integral type,
1956 there exist candidate operator functions of the form
1957 T* operator+(T*, I);
1958 T& operator[](T*, I);
1959 T* operator-(T*, I);
1960 T* operator+(I, T*);
1961 T& operator[](I, T*);
1963 15For every T, where T is a pointer to complete object type, there exist
1964 candidate operator functions of the form112)
1965 ptrdiff_t operator-(T, T);
1967 16For every pointer or enumeration type T, there exist candidate operator
1968 functions of the form
1969 bool operator<(T, T);
1970 bool operator>(T, T);
1971 bool operator<=(T, T);
1972 bool operator>=(T, T);
1973 bool operator==(T, T);
1974 bool operator!=(T, T);
1976 17For every pointer to member type T, there exist candidate operator
1977 functions of the form
1978 bool operator==(T, T);
1979 bool operator!=(T, T); */
1982 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1984 if (TYPE_PTROB_P (type1)
1985 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
1987 type2 = ptrdiff_type_node;
1991 case TRUNC_DIV_EXPR:
1992 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1998 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1999 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2001 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2006 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2018 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2020 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2022 if (TREE_CODE (type1) == ENUMERAL_TYPE
2023 && TREE_CODE (type2) == ENUMERAL_TYPE)
2025 if (TYPE_PTR_P (type1)
2026 && null_ptr_cst_p (args[1])
2027 && !uses_template_parms (type1))
2032 if (null_ptr_cst_p (args[0])
2033 && TYPE_PTR_P (type2)
2034 && !uses_template_parms (type2))
2042 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2045 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2047 type1 = ptrdiff_type_node;
2050 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2052 type2 = ptrdiff_type_node;
2057 /* 18For every pair of promoted integral types L and R, there exist candi-
2058 date operator functions of the form
2065 where LR is the result of the usual arithmetic conversions between
2068 case TRUNC_MOD_EXPR:
2074 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2078 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2079 type, VQ is either volatile or empty, and R is a promoted arithmetic
2080 type, there exist candidate operator functions of the form
2081 VQ L& operator=(VQ L&, R);
2082 VQ L& operator*=(VQ L&, R);
2083 VQ L& operator/=(VQ L&, R);
2084 VQ L& operator+=(VQ L&, R);
2085 VQ L& operator-=(VQ L&, R);
2087 20For every pair T, VQ), where T is any type and VQ is either volatile
2088 or empty, there exist candidate operator functions of the form
2089 T*VQ& operator=(T*VQ&, T*);
2091 21For every pair T, VQ), where T is a pointer to member type and VQ is
2092 either volatile or empty, there exist candidate operator functions of
2094 VQ T& operator=(VQ T&, T);
2096 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2097 unqualified complete object type, VQ is either volatile or empty, and
2098 I is a promoted integral type, there exist candidate operator func-
2100 T*VQ& operator+=(T*VQ&, I);
2101 T*VQ& operator-=(T*VQ&, I);
2103 23For every triple L, VQ, R), where L is an integral or enumeration
2104 type, VQ is either volatile or empty, and R is a promoted integral
2105 type, there exist candidate operator functions of the form
2107 VQ L& operator%=(VQ L&, R);
2108 VQ L& operator<<=(VQ L&, R);
2109 VQ L& operator>>=(VQ L&, R);
2110 VQ L& operator&=(VQ L&, R);
2111 VQ L& operator^=(VQ L&, R);
2112 VQ L& operator|=(VQ L&, R); */
2119 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2121 type2 = ptrdiff_type_node;
2125 case TRUNC_DIV_EXPR:
2126 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2130 case TRUNC_MOD_EXPR:
2136 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2141 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2143 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2144 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2145 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2146 || ((TYPE_PTRMEMFUNC_P (type1)
2147 || TREE_CODE (type1) == POINTER_TYPE)
2148 && null_ptr_cst_p (args[1])))
2158 type1 = build_reference_type (type1);
2164 For every pair of promoted arithmetic types L and R, there
2165 exist candidate operator functions of the form
2167 LR operator?(bool, L, R);
2169 where LR is the result of the usual arithmetic conversions
2170 between types L and R.
2172 For every type T, where T is a pointer or pointer-to-member
2173 type, there exist candidate operator functions of the form T
2174 operator?(bool, T, T); */
2176 if (promoted_arithmetic_type_p (type1)
2177 && promoted_arithmetic_type_p (type2))
2181 /* Otherwise, the types should be pointers. */
2182 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2183 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2186 /* We don't check that the two types are the same; the logic
2187 below will actually create two candidates; one in which both
2188 parameter types are TYPE1, and one in which both parameter
2196 /* If we're dealing with two pointer types or two enumeral types,
2197 we need candidates for both of them. */
2198 if (type2 && !same_type_p (type1, type2)
2199 && TREE_CODE (type1) == TREE_CODE (type2)
2200 && (TREE_CODE (type1) == REFERENCE_TYPE
2201 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2202 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2203 || TYPE_PTRMEMFUNC_P (type1)
2204 || MAYBE_CLASS_TYPE_P (type1)
2205 || TREE_CODE (type1) == ENUMERAL_TYPE))
2207 build_builtin_candidate
2208 (candidates, fnname, type1, type1, args, argtypes, flags);
2209 build_builtin_candidate
2210 (candidates, fnname, type2, type2, args, argtypes, flags);
2214 build_builtin_candidate
2215 (candidates, fnname, type1, type2, args, argtypes, flags);
2219 type_decays_to (tree type)
2221 if (TREE_CODE (type) == ARRAY_TYPE)
2222 return build_pointer_type (TREE_TYPE (type));
2223 if (TREE_CODE (type) == FUNCTION_TYPE)
2224 return build_pointer_type (type);
2228 /* There are three conditions of builtin candidates:
2230 1) bool-taking candidates. These are the same regardless of the input.
2231 2) pointer-pair taking candidates. These are generated for each type
2232 one of the input types converts to.
2233 3) arithmetic candidates. According to the standard, we should generate
2234 all of these, but I'm trying not to...
2236 Here we generate a superset of the possible candidates for this particular
2237 case. That is a subset of the full set the standard defines, plus some
2238 other cases which the standard disallows. add_builtin_candidate will
2239 filter out the invalid set. */
2242 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2243 enum tree_code code2, tree fnname, tree *args,
2248 tree type, argtypes[3];
2249 /* TYPES[i] is the set of possible builtin-operator parameter types
2250 we will consider for the Ith argument. These are represented as
2251 a TREE_LIST; the TREE_VALUE of each node is the potential
2255 for (i = 0; i < 3; ++i)
2258 argtypes[i] = unlowered_expr_type (args[i]);
2260 argtypes[i] = NULL_TREE;
2265 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2266 and VQ is either volatile or empty, there exist candidate operator
2267 functions of the form
2268 VQ T& operator++(VQ T&); */
2270 case POSTINCREMENT_EXPR:
2271 case PREINCREMENT_EXPR:
2272 case POSTDECREMENT_EXPR:
2273 case PREDECREMENT_EXPR:
2278 /* 24There also exist candidate operator functions of the form
2279 bool operator!(bool);
2280 bool operator&&(bool, bool);
2281 bool operator||(bool, bool); */
2283 case TRUTH_NOT_EXPR:
2284 build_builtin_candidate
2285 (candidates, fnname, boolean_type_node,
2286 NULL_TREE, args, argtypes, flags);
2289 case TRUTH_ORIF_EXPR:
2290 case TRUTH_ANDIF_EXPR:
2291 build_builtin_candidate
2292 (candidates, fnname, boolean_type_node,
2293 boolean_type_node, args, argtypes, flags);
2315 types[0] = types[1] = NULL_TREE;
2317 for (i = 0; i < 2; ++i)
2321 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2325 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2328 convs = lookup_conversions (argtypes[i]);
2330 if (code == COND_EXPR)
2332 if (real_lvalue_p (args[i]))
2333 types[i] = tree_cons
2334 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2336 types[i] = tree_cons
2337 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2343 for (; convs; convs = TREE_CHAIN (convs))
2345 type = TREE_TYPE (convs);
2348 && (TREE_CODE (type) != REFERENCE_TYPE
2349 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2352 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2353 types[i] = tree_cons (NULL_TREE, type, types[i]);
2355 type = non_reference (type);
2356 if (i != 0 || ! ref1)
2358 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2359 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2360 types[i] = tree_cons (NULL_TREE, type, types[i]);
2361 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2362 type = type_promotes_to (type);
2365 if (! value_member (type, types[i]))
2366 types[i] = tree_cons (NULL_TREE, type, types[i]);
2371 if (code == COND_EXPR && real_lvalue_p (args[i]))
2372 types[i] = tree_cons
2373 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2374 type = non_reference (argtypes[i]);
2375 if (i != 0 || ! ref1)
2377 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2378 if (enum_p && UNSCOPED_ENUM_P (type))
2379 types[i] = tree_cons (NULL_TREE, type, types[i]);
2380 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2381 type = type_promotes_to (type);
2383 types[i] = tree_cons (NULL_TREE, type, types[i]);
2387 /* Run through the possible parameter types of both arguments,
2388 creating candidates with those parameter types. */
2389 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2392 for (type = types[1]; type; type = TREE_CHAIN (type))
2393 add_builtin_candidate
2394 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2395 TREE_VALUE (type), args, argtypes, flags);
2397 add_builtin_candidate
2398 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2399 NULL_TREE, args, argtypes, flags);
2404 /* If TMPL can be successfully instantiated as indicated by
2405 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2407 TMPL is the template. EXPLICIT_TARGS are any explicit template
2408 arguments. ARGLIST is the arguments provided at the call-site.
2409 This does not change ARGLIST. The RETURN_TYPE is the desired type
2410 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2411 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2412 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2414 static struct z_candidate*
2415 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2416 tree ctype, tree explicit_targs, tree first_arg,
2417 const VEC(tree,gc) *arglist, tree return_type,
2418 tree access_path, tree conversion_path,
2419 int flags, tree obj, unification_kind_t strict)
2421 int ntparms = DECL_NTPARMS (tmpl);
2422 tree targs = make_tree_vec (ntparms);
2424 int skip_without_in_chrg;
2425 tree first_arg_without_in_chrg;
2426 tree *args_without_in_chrg;
2427 unsigned int nargs_without_in_chrg;
2428 unsigned int ia, ix;
2430 struct z_candidate *cand;
2434 nargs = (first_arg == NULL_TREE ? 0 : 1) + VEC_length (tree, arglist);
2436 skip_without_in_chrg = 0;
2438 first_arg_without_in_chrg = first_arg;
2440 /* We don't do deduction on the in-charge parameter, the VTT
2441 parameter or 'this'. */
2442 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2444 if (first_arg_without_in_chrg != NULL_TREE)
2445 first_arg_without_in_chrg = NULL_TREE;
2447 ++skip_without_in_chrg;
2450 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2451 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2452 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2454 if (first_arg_without_in_chrg != NULL_TREE)
2455 first_arg_without_in_chrg = NULL_TREE;
2457 ++skip_without_in_chrg;
2460 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2461 + (VEC_length (tree, arglist)
2462 - skip_without_in_chrg));
2463 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2465 if (first_arg_without_in_chrg != NULL_TREE)
2467 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2470 for (ix = skip_without_in_chrg;
2471 VEC_iterate (tree, arglist, ix, arg);
2474 args_without_in_chrg[ia] = arg;
2477 gcc_assert (ia == nargs_without_in_chrg);
2479 i = fn_type_unification (tmpl, explicit_targs, targs,
2480 args_without_in_chrg,
2481 nargs_without_in_chrg,
2482 return_type, strict, flags);
2487 fn = instantiate_template (tmpl, targs, tf_none);
2488 if (fn == error_mark_node)
2493 A member function template is never instantiated to perform the
2494 copy of a class object to an object of its class type.
2496 It's a little unclear what this means; the standard explicitly
2497 does allow a template to be used to copy a class. For example,
2502 template <class T> A(const T&);
2505 void g () { A a (f ()); }
2507 the member template will be used to make the copy. The section
2508 quoted above appears in the paragraph that forbids constructors
2509 whose only parameter is (a possibly cv-qualified variant of) the
2510 class type, and a logical interpretation is that the intent was
2511 to forbid the instantiation of member templates which would then
2513 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2515 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2516 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2521 if (obj != NULL_TREE)
2522 /* Aha, this is a conversion function. */
2523 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2524 access_path, conversion_path);
2526 cand = add_function_candidate (candidates, fn, ctype,
2527 first_arg, arglist, access_path,
2528 conversion_path, flags);
2529 if (DECL_TI_TEMPLATE (fn) != tmpl)
2530 /* This situation can occur if a member template of a template
2531 class is specialized. Then, instantiate_template might return
2532 an instantiation of the specialization, in which case the
2533 DECL_TI_TEMPLATE field will point at the original
2534 specialization. For example:
2536 template <class T> struct S { template <class U> void f(U);
2537 template <> void f(int) {}; };
2541 Here, TMPL will be template <class U> S<double>::f(U).
2542 And, instantiate template will give us the specialization
2543 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2544 for this will point at template <class T> template <> S<T>::f(int),
2545 so that we can find the definition. For the purposes of
2546 overload resolution, however, we want the original TMPL. */
2547 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2549 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2555 static struct z_candidate *
2556 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2557 tree explicit_targs, tree first_arg,
2558 const VEC(tree,gc) *arglist, tree return_type,
2559 tree access_path, tree conversion_path, int flags,
2560 unification_kind_t strict)
2563 add_template_candidate_real (candidates, tmpl, ctype,
2564 explicit_targs, first_arg, arglist,
2565 return_type, access_path, conversion_path,
2566 flags, NULL_TREE, strict);
2570 static struct z_candidate *
2571 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2572 tree obj, tree first_arg,
2573 const VEC(tree,gc) *arglist,
2574 tree return_type, tree access_path,
2575 tree conversion_path)
2578 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2579 first_arg, arglist, return_type, access_path,
2580 conversion_path, 0, obj, DEDUCE_CONV);
2583 /* The CANDS are the set of candidates that were considered for
2584 overload resolution. Return the set of viable candidates. If none
2585 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2586 is true if a candidate should be considered viable only if it is
2589 static struct z_candidate*
2590 splice_viable (struct z_candidate *cands,
2594 struct z_candidate *viable;
2595 struct z_candidate **last_viable;
2596 struct z_candidate **cand;
2599 last_viable = &viable;
2600 *any_viable_p = false;
2605 struct z_candidate *c = *cand;
2606 if (strict_p ? c->viable == 1 : c->viable)
2611 last_viable = &c->next;
2612 *any_viable_p = true;
2618 return viable ? viable : cands;
2622 any_strictly_viable (struct z_candidate *cands)
2624 for (; cands; cands = cands->next)
2625 if (cands->viable == 1)
2630 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2631 words, it is about to become the "this" pointer for a member
2632 function call. Take the address of the object. */
2635 build_this (tree obj)
2637 /* In a template, we are only concerned about the type of the
2638 expression, so we can take a shortcut. */
2639 if (processing_template_decl)
2640 return build_address (obj);
2642 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2645 /* Returns true iff functions are equivalent. Equivalent functions are
2646 not '==' only if one is a function-local extern function or if
2647 both are extern "C". */
2650 equal_functions (tree fn1, tree fn2)
2652 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2653 || DECL_EXTERN_C_FUNCTION_P (fn1))
2654 return decls_match (fn1, fn2);
2658 /* Print information about one overload candidate CANDIDATE. MSGSTR
2659 is the text to print before the candidate itself.
2661 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2662 to have been run through gettext by the caller. This wart makes
2663 life simpler in print_z_candidates and for the translators. */
2666 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2668 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2670 if (candidate->num_convs == 3)
2671 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2672 candidate->convs[0]->type,
2673 candidate->convs[1]->type,
2674 candidate->convs[2]->type);
2675 else if (candidate->num_convs == 2)
2676 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2677 candidate->convs[0]->type,
2678 candidate->convs[1]->type);
2680 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2681 candidate->convs[0]->type);
2683 else if (TYPE_P (candidate->fn))
2684 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2685 else if (candidate->viable == -1)
2686 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2688 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2692 print_z_candidates (struct z_candidate *candidates)
2695 struct z_candidate *cand1;
2696 struct z_candidate **cand2;
2698 /* There may be duplicates in the set of candidates. We put off
2699 checking this condition as long as possible, since we have no way
2700 to eliminate duplicates from a set of functions in less than n^2
2701 time. Now we are about to emit an error message, so it is more
2702 permissible to go slowly. */
2703 for (cand1 = candidates; cand1; cand1 = cand1->next)
2705 tree fn = cand1->fn;
2706 /* Skip builtin candidates and conversion functions. */
2707 if (TREE_CODE (fn) != FUNCTION_DECL)
2709 cand2 = &cand1->next;
2712 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2713 && equal_functions (fn, (*cand2)->fn))
2714 *cand2 = (*cand2)->next;
2716 cand2 = &(*cand2)->next;
2723 str = _("candidates are:");
2724 print_z_candidate (str, candidates);
2725 if (candidates->next)
2727 /* Indent successive candidates by the width of the translation
2728 of the above string. */
2729 size_t len = gcc_gettext_width (str) + 1;
2730 char *spaces = (char *) alloca (len);
2731 memset (spaces, ' ', len-1);
2732 spaces[len - 1] = '\0';
2734 candidates = candidates->next;
2737 print_z_candidate (spaces, candidates);
2738 candidates = candidates->next;
2744 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2745 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2746 the result of the conversion function to convert it to the final
2747 desired type. Merge the two sequences into a single sequence,
2748 and return the merged sequence. */
2751 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2755 gcc_assert (user_seq->kind == ck_user);
2757 /* Find the end of the second conversion sequence. */
2759 while ((*t)->kind != ck_identity)
2760 t = &((*t)->u.next);
2762 /* Replace the identity conversion with the user conversion
2766 /* The entire sequence is a user-conversion sequence. */
2767 std_seq->user_conv_p = true;
2772 /* Returns the best overload candidate to perform the requested
2773 conversion. This function is used for three the overloading situations
2774 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2775 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2776 per [dcl.init.ref], so we ignore temporary bindings. */
2778 static struct z_candidate *
2779 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2781 struct z_candidate *candidates, *cand;
2782 tree fromtype = TREE_TYPE (expr);
2783 tree ctors = NULL_TREE;
2784 tree conv_fns = NULL_TREE;
2785 conversion *conv = NULL;
2786 tree first_arg = NULL_TREE;
2787 VEC(tree,gc) *args = NULL;
2791 /* We represent conversion within a hierarchy using RVALUE_CONV and
2792 BASE_CONV, as specified by [over.best.ics]; these become plain
2793 constructor calls, as specified in [dcl.init]. */
2794 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2795 || !DERIVED_FROM_P (totype, fromtype));
2797 if (MAYBE_CLASS_TYPE_P (totype))
2798 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2800 if (MAYBE_CLASS_TYPE_P (fromtype))
2802 tree to_nonref = non_reference (totype);
2803 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2804 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2805 && DERIVED_FROM_P (to_nonref, fromtype)))
2807 /* [class.conv.fct] A conversion function is never used to
2808 convert a (possibly cv-qualified) object to the (possibly
2809 cv-qualified) same object type (or a reference to it), to a
2810 (possibly cv-qualified) base class of that type (or a
2811 reference to it)... */
2814 conv_fns = lookup_conversions (fromtype);
2818 flags |= LOOKUP_NO_CONVERSION;
2820 /* It's OK to bind a temporary for converting constructor arguments, but
2821 not in converting the return value of a conversion operator. */
2822 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2823 flags &= ~LOOKUP_NO_TEMP_BIND;
2827 ctors = BASELINK_FUNCTIONS (ctors);
2829 first_arg = build_int_cst (build_pointer_type (totype), 0);
2830 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2831 && !TYPE_HAS_LIST_CTOR (totype))
2833 args = ctor_to_vec (expr);
2834 /* We still allow more conversions within an init-list. */
2835 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2836 /* But not for the copy ctor. */
2837 |LOOKUP_NO_COPY_CTOR_CONVERSION
2838 |LOOKUP_NO_NARROWING);
2841 args = make_tree_vector_single (expr);
2843 /* We should never try to call the abstract or base constructor
2845 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2846 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2848 for (; ctors; ctors = OVL_NEXT (ctors))
2850 tree ctor = OVL_CURRENT (ctors);
2851 if (DECL_NONCONVERTING_P (ctor)
2852 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2855 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2856 cand = add_template_candidate (&candidates, ctor, totype,
2857 NULL_TREE, first_arg, args, NULL_TREE,
2858 TYPE_BINFO (totype),
2859 TYPE_BINFO (totype),
2863 cand = add_function_candidate (&candidates, ctor, totype,
2864 first_arg, args, TYPE_BINFO (totype),
2865 TYPE_BINFO (totype),
2870 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2872 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2873 set, then this is copy-initialization. In that case, "The
2874 result of the call is then used to direct-initialize the
2875 object that is the destination of the copy-initialization."
2878 We represent this in the conversion sequence with an
2879 rvalue conversion, which means a constructor call. */
2880 if (TREE_CODE (totype) != REFERENCE_TYPE
2881 && !(convflags & LOOKUP_NO_TEMP_BIND))
2883 = build_conv (ck_rvalue, totype, cand->second_conv);
2888 first_arg = build_this (expr);
2890 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2893 tree conversion_path = TREE_PURPOSE (conv_fns);
2895 /* If we are called to convert to a reference type, we are trying to
2896 find an lvalue binding, so don't even consider temporaries. If
2897 we don't find an lvalue binding, the caller will try again to
2898 look for a temporary binding. */
2899 if (TREE_CODE (totype) == REFERENCE_TYPE)
2900 convflags |= LOOKUP_NO_TEMP_BIND;
2902 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2904 tree fn = OVL_CURRENT (fns);
2906 if (DECL_NONCONVERTING_P (fn)
2907 && (flags & LOOKUP_ONLYCONVERTING))
2910 /* [over.match.funcs] For conversion functions, the function
2911 is considered to be a member of the class of the implicit
2912 object argument for the purpose of defining the type of
2913 the implicit object parameter.
2915 So we pass fromtype as CTYPE to add_*_candidate. */
2917 if (TREE_CODE (fn) == TEMPLATE_DECL)
2918 cand = add_template_candidate (&candidates, fn, fromtype,
2920 first_arg, NULL, totype,
2921 TYPE_BINFO (fromtype),
2926 cand = add_function_candidate (&candidates, fn, fromtype,
2928 TYPE_BINFO (fromtype),
2935 = implicit_conversion (totype,
2936 TREE_TYPE (TREE_TYPE (cand->fn)),
2938 /*c_cast_p=*/false, convflags);
2940 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2941 copy-initialization. In that case, "The result of the
2942 call is then used to direct-initialize the object that is
2943 the destination of the copy-initialization." [dcl.init]
2945 We represent this in the conversion sequence with an
2946 rvalue conversion, which means a constructor call. But
2947 don't add a second rvalue conversion if there's already
2948 one there. Which there really shouldn't be, but it's
2949 harmless since we'd add it here anyway. */
2950 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2951 && !(convflags & LOOKUP_NO_TEMP_BIND))
2952 ics = build_conv (ck_rvalue, totype, ics);
2954 cand->second_conv = ics;
2958 else if (candidates->viable == 1 && ics->bad_p)
2964 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2968 cand = tourney (candidates);
2971 if (flags & LOOKUP_COMPLAIN)
2973 error ("conversion from %qT to %qT is ambiguous",
2975 print_z_candidates (candidates);
2978 cand = candidates; /* any one will do */
2979 cand->second_conv = build_ambiguous_conv (totype, expr);
2980 cand->second_conv->user_conv_p = true;
2981 if (!any_strictly_viable (candidates))
2982 cand->second_conv->bad_p = true;
2983 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2984 ambiguous conversion is no worse than another user-defined
2990 /* Build the user conversion sequence. */
2993 (DECL_CONSTRUCTOR_P (cand->fn)
2994 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2995 build_identity_conv (TREE_TYPE (expr), expr));
2998 /* Remember that this was a list-initialization. */
2999 if (flags & LOOKUP_NO_NARROWING)
3000 conv->check_narrowing = true;
3002 /* Combine it with the second conversion sequence. */
3003 cand->second_conv = merge_conversion_sequences (conv,
3006 if (cand->viable == -1)
3007 cand->second_conv->bad_p = true;
3013 build_user_type_conversion (tree totype, tree expr, int flags)
3015 struct z_candidate *cand
3016 = build_user_type_conversion_1 (totype, expr, flags);
3020 if (cand->second_conv->kind == ck_ambig)
3021 return error_mark_node;
3022 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3023 return convert_from_reference (expr);
3028 /* Do any initial processing on the arguments to a function call. */
3030 static VEC(tree,gc) *
3031 resolve_args (VEC(tree,gc) *args)
3036 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3038 if (error_operand_p (arg))
3040 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3042 error ("invalid use of void expression");
3045 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3051 /* Perform overload resolution on FN, which is called with the ARGS.
3053 Return the candidate function selected by overload resolution, or
3054 NULL if the event that overload resolution failed. In the case
3055 that overload resolution fails, *CANDIDATES will be the set of
3056 candidates considered, and ANY_VIABLE_P will be set to true or
3057 false to indicate whether or not any of the candidates were
3060 The ARGS should already have gone through RESOLVE_ARGS before this
3061 function is called. */
3063 static struct z_candidate *
3064 perform_overload_resolution (tree fn,
3065 const VEC(tree,gc) *args,
3066 struct z_candidate **candidates,
3069 struct z_candidate *cand;
3070 tree explicit_targs = NULL_TREE;
3071 int template_only = 0;
3074 *any_viable_p = true;
3077 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3078 || TREE_CODE (fn) == TEMPLATE_DECL
3079 || TREE_CODE (fn) == OVERLOAD
3080 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3082 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3084 explicit_targs = TREE_OPERAND (fn, 1);
3085 fn = TREE_OPERAND (fn, 0);
3089 /* Add the various candidate functions. */
3090 add_candidates (fn, args, explicit_targs, template_only,
3091 /*conversion_path=*/NULL_TREE,
3092 /*access_path=*/NULL_TREE,
3096 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3100 cand = tourney (*candidates);
3104 /* Return an expression for a call to FN (a namespace-scope function,
3105 or a static member function) with the ARGS. This may change
3109 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3110 tsubst_flags_t complain)
3112 struct z_candidate *candidates, *cand;
3117 if (args != NULL && *args != NULL)
3119 *args = resolve_args (*args);
3121 return error_mark_node;
3124 /* If this function was found without using argument dependent
3125 lookup, then we want to ignore any undeclared friend
3131 fn = remove_hidden_names (fn);
3134 if (complain & tf_error)
3135 error ("no matching function for call to %<%D(%A)%>",
3136 DECL_NAME (OVL_CURRENT (orig_fn)),
3137 build_tree_list_vec (*args));
3138 return error_mark_node;
3142 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3143 p = conversion_obstack_alloc (0);
3145 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3149 if (complain & tf_error)
3151 if (!any_viable_p && candidates && ! candidates->next)
3152 return cp_build_function_call_vec (candidates->fn, args, complain);
3153 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3154 fn = TREE_OPERAND (fn, 0);
3156 error ("no matching function for call to %<%D(%A)%>",
3157 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3159 error ("call of overloaded %<%D(%A)%> is ambiguous",
3160 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3162 print_z_candidates (candidates);
3164 result = error_mark_node;
3167 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3169 /* Free all the conversions we allocated. */
3170 obstack_free (&conversion_obstack, p);
3175 /* Build a call to a global operator new. FNNAME is the name of the
3176 operator (either "operator new" or "operator new[]") and ARGS are
3177 the arguments provided. This may change ARGS. *SIZE points to the
3178 total number of bytes required by the allocation, and is updated if
3179 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3180 be used. If this function determines that no cookie should be
3181 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3182 non-NULL, it will be set, upon return, to the allocation function
3186 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3187 tree *size, tree *cookie_size,
3191 struct z_candidate *candidates;
3192 struct z_candidate *cand;
3197 VEC_safe_insert (tree, gc, *args, 0, *size);
3198 *args = resolve_args (*args);
3200 return error_mark_node;
3206 If this lookup fails to find the name, or if the allocated type
3207 is not a class type, the allocation function's name is looked
3208 up in the global scope.
3210 we disregard block-scope declarations of "operator new". */
3211 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3213 /* Figure out what function is being called. */
3214 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3216 /* If no suitable function could be found, issue an error message
3221 error ("no matching function for call to %<%D(%A)%>",
3222 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3224 error ("call of overloaded %<%D(%A)%> is ambiguous",
3225 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3227 print_z_candidates (candidates);
3228 return error_mark_node;
3231 /* If a cookie is required, add some extra space. Whether
3232 or not a cookie is required cannot be determined until
3233 after we know which function was called. */
3236 bool use_cookie = true;
3237 if (!abi_version_at_least (2))
3239 /* In G++ 3.2, the check was implemented incorrectly; it
3240 looked at the placement expression, rather than the
3241 type of the function. */
3242 if (VEC_length (tree, *args) == 2
3243 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3251 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3252 /* Skip the size_t parameter. */
3253 arg_types = TREE_CHAIN (arg_types);
3254 /* Check the remaining parameters (if any). */
3256 && TREE_CHAIN (arg_types) == void_list_node
3257 && same_type_p (TREE_VALUE (arg_types),
3261 /* If we need a cookie, adjust the number of bytes allocated. */
3264 /* Update the total size. */
3265 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3266 /* Update the argument list to reflect the adjusted size. */
3267 VEC_replace (tree, *args, 0, *size);
3270 *cookie_size = NULL_TREE;
3273 /* Tell our caller which function we decided to call. */
3277 /* Build the CALL_EXPR. */
3278 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3281 /* Build a new call to operator(). This may change ARGS. */
3284 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3286 struct z_candidate *candidates = 0, *cand;
3287 tree fns, convs, first_mem_arg = NULL_TREE;
3288 tree type = TREE_TYPE (obj);
3290 tree result = NULL_TREE;
3293 if (error_operand_p (obj))
3294 return error_mark_node;
3296 obj = prep_operand (obj);
3298 if (TYPE_PTRMEMFUNC_P (type))
3300 if (complain & tf_error)
3301 /* It's no good looking for an overloaded operator() on a
3302 pointer-to-member-function. */
3303 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3304 return error_mark_node;
3307 if (TYPE_BINFO (type))
3309 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3310 if (fns == error_mark_node)
3311 return error_mark_node;
3316 if (args != NULL && *args != NULL)
3318 *args = resolve_args (*args);
3320 return error_mark_node;
3323 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3324 p = conversion_obstack_alloc (0);
3328 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3329 first_mem_arg = build_this (obj);
3331 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3333 tree fn = OVL_CURRENT (fns);
3334 if (TREE_CODE (fn) == TEMPLATE_DECL)
3335 add_template_candidate (&candidates, fn, base, NULL_TREE,
3336 first_mem_arg, *args, NULL_TREE,
3339 LOOKUP_NORMAL, DEDUCE_CALL);
3341 add_function_candidate
3342 (&candidates, fn, base, first_mem_arg, *args, TYPE_BINFO (type),
3343 TYPE_BINFO (type), LOOKUP_NORMAL);
3347 convs = lookup_conversions (type);
3349 for (; convs; convs = TREE_CHAIN (convs))
3351 tree fns = TREE_VALUE (convs);
3352 tree totype = TREE_TYPE (convs);
3354 if ((TREE_CODE (totype) == POINTER_TYPE
3355 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3356 || (TREE_CODE (totype) == REFERENCE_TYPE
3357 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3358 || (TREE_CODE (totype) == REFERENCE_TYPE
3359 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3360 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3361 for (; fns; fns = OVL_NEXT (fns))
3363 tree fn = OVL_CURRENT (fns);
3365 if (DECL_NONCONVERTING_P (fn))
3368 if (TREE_CODE (fn) == TEMPLATE_DECL)
3369 add_template_conv_candidate
3370 (&candidates, fn, obj, NULL_TREE, *args, totype,
3371 /*access_path=*/NULL_TREE,
3372 /*conversion_path=*/NULL_TREE);
3374 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3375 *args, /*conversion_path=*/NULL_TREE,
3376 /*access_path=*/NULL_TREE);
3380 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3383 if (complain & tf_error)
3385 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3386 build_tree_list_vec (*args));
3387 print_z_candidates (candidates);
3389 result = error_mark_node;
3393 cand = tourney (candidates);
3396 if (complain & tf_error)
3398 error ("call of %<(%T) (%A)%> is ambiguous",
3399 TREE_TYPE (obj), build_tree_list_vec (*args));
3400 print_z_candidates (candidates);
3402 result = error_mark_node;
3404 /* Since cand->fn will be a type, not a function, for a conversion
3405 function, we must be careful not to unconditionally look at
3407 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3408 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3409 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3412 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3414 obj = convert_from_reference (obj);
3415 result = cp_build_function_call_vec (obj, args, complain);
3419 /* Free all the conversions we allocated. */
3420 obstack_free (&conversion_obstack, p);
3426 op_error (enum tree_code code, enum tree_code code2,
3427 tree arg1, tree arg2, tree arg3, const char *problem)
3431 if (code == MODIFY_EXPR)
3432 opname = assignment_operator_name_info[code2].name;
3434 opname = operator_name_info[code].name;
3439 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3440 problem, arg1, arg2, arg3);
3443 case POSTINCREMENT_EXPR:
3444 case POSTDECREMENT_EXPR:
3445 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3449 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3454 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3459 error ("%s for %<operator%s%> in %<%E %s %E%>",
3460 problem, opname, arg1, opname, arg2);
3462 error ("%s for %<operator%s%> in %<%s%E%>",
3463 problem, opname, opname, arg1);
3468 /* Return the implicit conversion sequence that could be used to
3469 convert E1 to E2 in [expr.cond]. */
3472 conditional_conversion (tree e1, tree e2)
3474 tree t1 = non_reference (TREE_TYPE (e1));
3475 tree t2 = non_reference (TREE_TYPE (e2));
3481 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3482 implicitly converted (clause _conv_) to the type "reference to
3483 T2", subject to the constraint that in the conversion the
3484 reference must bind directly (_dcl.init.ref_) to E1. */
3485 if (real_lvalue_p (e2))
3487 conv = implicit_conversion (build_reference_type (t2),
3491 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3498 If E1 and E2 have class type, and the underlying class types are
3499 the same or one is a base class of the other: E1 can be converted
3500 to match E2 if the class of T2 is the same type as, or a base
3501 class of, the class of T1, and the cv-qualification of T2 is the
3502 same cv-qualification as, or a greater cv-qualification than, the
3503 cv-qualification of T1. If the conversion is applied, E1 is
3504 changed to an rvalue of type T2 that still refers to the original
3505 source class object (or the appropriate subobject thereof). */
3506 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3507 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3509 if (good_base && at_least_as_qualified_p (t2, t1))
3511 conv = build_identity_conv (t1, e1);
3512 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3513 TYPE_MAIN_VARIANT (t2)))
3514 conv = build_conv (ck_base, t2, conv);
3516 conv = build_conv (ck_rvalue, t2, conv);
3525 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3526 converted to the type that expression E2 would have if E2 were
3527 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3528 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3532 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3533 arguments to the conditional expression. */
3536 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3537 tsubst_flags_t complain)
3541 tree result = NULL_TREE;
3542 tree result_type = NULL_TREE;
3543 bool lvalue_p = true;
3544 struct z_candidate *candidates = 0;
3545 struct z_candidate *cand;
3548 /* As a G++ extension, the second argument to the conditional can be
3549 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3550 c'.) If the second operand is omitted, make sure it is
3551 calculated only once. */
3554 if (complain & tf_error)
3555 pedwarn (input_location, OPT_pedantic,
3556 "ISO C++ forbids omitting the middle term of a ?: expression");
3558 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3559 if (real_lvalue_p (arg1))
3560 arg2 = arg1 = stabilize_reference (arg1);
3562 arg2 = arg1 = save_expr (arg1);
3567 The first expression is implicitly converted to bool (clause
3569 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3571 /* If something has already gone wrong, just pass that fact up the
3573 if (error_operand_p (arg1)
3574 || error_operand_p (arg2)
3575 || error_operand_p (arg3))
3576 return error_mark_node;
3580 If either the second or the third operand has type (possibly
3581 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3582 array-to-pointer (_conv.array_), and function-to-pointer
3583 (_conv.func_) standard conversions are performed on the second
3584 and third operands. */
3585 arg2_type = unlowered_expr_type (arg2);
3586 arg3_type = unlowered_expr_type (arg3);
3587 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3589 /* Do the conversions. We don't these for `void' type arguments
3590 since it can't have any effect and since decay_conversion
3591 does not handle that case gracefully. */
3592 if (!VOID_TYPE_P (arg2_type))
3593 arg2 = decay_conversion (arg2);
3594 if (!VOID_TYPE_P (arg3_type))
3595 arg3 = decay_conversion (arg3);
3596 arg2_type = TREE_TYPE (arg2);
3597 arg3_type = TREE_TYPE (arg3);
3601 One of the following shall hold:
3603 --The second or the third operand (but not both) is a
3604 throw-expression (_except.throw_); the result is of the
3605 type of the other and is an rvalue.
3607 --Both the second and the third operands have type void; the
3608 result is of type void and is an rvalue.
3610 We must avoid calling force_rvalue for expressions of type
3611 "void" because it will complain that their value is being
3613 if (TREE_CODE (arg2) == THROW_EXPR
3614 && TREE_CODE (arg3) != THROW_EXPR)
3616 if (!VOID_TYPE_P (arg3_type))
3617 arg3 = force_rvalue (arg3);
3618 arg3_type = TREE_TYPE (arg3);
3619 result_type = arg3_type;
3621 else if (TREE_CODE (arg2) != THROW_EXPR
3622 && TREE_CODE (arg3) == THROW_EXPR)
3624 if (!VOID_TYPE_P (arg2_type))
3625 arg2 = force_rvalue (arg2);
3626 arg2_type = TREE_TYPE (arg2);
3627 result_type = arg2_type;
3629 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3630 result_type = void_type_node;
3633 if (complain & tf_error)
3635 if (VOID_TYPE_P (arg2_type))
3636 error ("second operand to the conditional operator "
3637 "is of type %<void%>, "
3638 "but the third operand is neither a throw-expression "
3639 "nor of type %<void%>");
3641 error ("third operand to the conditional operator "
3642 "is of type %<void%>, "
3643 "but the second operand is neither a throw-expression "
3644 "nor of type %<void%>");
3646 return error_mark_node;
3650 goto valid_operands;
3654 Otherwise, if the second and third operand have different types,
3655 and either has (possibly cv-qualified) class type, an attempt is
3656 made to convert each of those operands to the type of the other. */
3657 else if (!same_type_p (arg2_type, arg3_type)
3658 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3663 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3664 p = conversion_obstack_alloc (0);
3666 conv2 = conditional_conversion (arg2, arg3);
3667 conv3 = conditional_conversion (arg3, arg2);
3671 If both can be converted, or one can be converted but the
3672 conversion is ambiguous, the program is ill-formed. If
3673 neither can be converted, the operands are left unchanged and
3674 further checking is performed as described below. If exactly
3675 one conversion is possible, that conversion is applied to the
3676 chosen operand and the converted operand is used in place of
3677 the original operand for the remainder of this section. */
3678 if ((conv2 && !conv2->bad_p
3679 && conv3 && !conv3->bad_p)
3680 || (conv2 && conv2->kind == ck_ambig)
3681 || (conv3 && conv3->kind == ck_ambig))
3683 error ("operands to ?: have different types %qT and %qT",
3684 arg2_type, arg3_type);
3685 result = error_mark_node;
3687 else if (conv2 && (!conv2->bad_p || !conv3))
3689 arg2 = convert_like (conv2, arg2, complain);
3690 arg2 = convert_from_reference (arg2);
3691 arg2_type = TREE_TYPE (arg2);
3692 /* Even if CONV2 is a valid conversion, the result of the
3693 conversion may be invalid. For example, if ARG3 has type
3694 "volatile X", and X does not have a copy constructor
3695 accepting a "volatile X&", then even if ARG2 can be
3696 converted to X, the conversion will fail. */
3697 if (error_operand_p (arg2))
3698 result = error_mark_node;
3700 else if (conv3 && (!conv3->bad_p || !conv2))
3702 arg3 = convert_like (conv3, arg3, complain);
3703 arg3 = convert_from_reference (arg3);
3704 arg3_type = TREE_TYPE (arg3);
3705 if (error_operand_p (arg3))
3706 result = error_mark_node;
3709 /* Free all the conversions we allocated. */
3710 obstack_free (&conversion_obstack, p);
3715 /* If, after the conversion, both operands have class type,
3716 treat the cv-qualification of both operands as if it were the
3717 union of the cv-qualification of the operands.
3719 The standard is not clear about what to do in this
3720 circumstance. For example, if the first operand has type
3721 "const X" and the second operand has a user-defined
3722 conversion to "volatile X", what is the type of the second
3723 operand after this step? Making it be "const X" (matching
3724 the first operand) seems wrong, as that discards the
3725 qualification without actually performing a copy. Leaving it
3726 as "volatile X" seems wrong as that will result in the
3727 conditional expression failing altogether, even though,
3728 according to this step, the one operand could be converted to
3729 the type of the other. */
3730 if ((conv2 || conv3)
3731 && CLASS_TYPE_P (arg2_type)
3732 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3733 arg2_type = arg3_type =
3734 cp_build_qualified_type (arg2_type,
3735 TYPE_QUALS (arg2_type)
3736 | TYPE_QUALS (arg3_type));
3741 If the second and third operands are lvalues and have the same
3742 type, the result is of that type and is an lvalue. */
3743 if (real_lvalue_p (arg2)
3744 && real_lvalue_p (arg3)
3745 && same_type_p (arg2_type, arg3_type))
3747 result_type = arg2_type;
3748 goto valid_operands;
3753 Otherwise, the result is an rvalue. If the second and third
3754 operand do not have the same type, and either has (possibly
3755 cv-qualified) class type, overload resolution is used to
3756 determine the conversions (if any) to be applied to the operands
3757 (_over.match.oper_, _over.built_). */
3759 if (!same_type_p (arg2_type, arg3_type)
3760 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3766 /* Rearrange the arguments so that add_builtin_candidate only has
3767 to know about two args. In build_builtin_candidates, the
3768 arguments are unscrambled. */
3772 add_builtin_candidates (&candidates,
3775 ansi_opname (COND_EXPR),
3781 If the overload resolution fails, the program is
3783 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3786 if (complain & tf_error)
3788 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3789 print_z_candidates (candidates);
3791 return error_mark_node;
3793 cand = tourney (candidates);
3796 if (complain & tf_error)
3798 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3799 print_z_candidates (candidates);
3801 return error_mark_node;
3806 Otherwise, the conversions thus determined are applied, and
3807 the converted operands are used in place of the original
3808 operands for the remainder of this section. */
3809 conv = cand->convs[0];
3810 arg1 = convert_like (conv, arg1, complain);
3811 conv = cand->convs[1];
3812 arg2 = convert_like (conv, arg2, complain);
3813 conv = cand->convs[2];
3814 arg3 = convert_like (conv, arg3, complain);
3819 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3820 and function-to-pointer (_conv.func_) standard conversions are
3821 performed on the second and third operands.
3823 We need to force the lvalue-to-rvalue conversion here for class types,
3824 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3825 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3828 arg2 = force_rvalue (arg2);
3829 if (!CLASS_TYPE_P (arg2_type))
3830 arg2_type = TREE_TYPE (arg2);
3832 arg3 = force_rvalue (arg3);
3833 if (!CLASS_TYPE_P (arg2_type))
3834 arg3_type = TREE_TYPE (arg3);
3836 if (arg2 == error_mark_node || arg3 == error_mark_node)
3837 return error_mark_node;
3841 After those conversions, one of the following shall hold:
3843 --The second and third operands have the same type; the result is of
3845 if (same_type_p (arg2_type, arg3_type))
3846 result_type = arg2_type;
3849 --The second and third operands have arithmetic or enumeration
3850 type; the usual arithmetic conversions are performed to bring
3851 them to a common type, and the result is of that type. */
3852 else if ((ARITHMETIC_TYPE_P (arg2_type)
3853 || UNSCOPED_ENUM_P (arg2_type))
3854 && (ARITHMETIC_TYPE_P (arg3_type)
3855 || UNSCOPED_ENUM_P (arg3_type)))
3857 /* In this case, there is always a common type. */
3858 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3861 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3862 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3864 if (complain & tf_warning)
3866 "enumeral mismatch in conditional expression: %qT vs %qT",
3867 arg2_type, arg3_type);
3869 else if (extra_warnings
3870 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3871 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3872 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3873 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3875 if (complain & tf_warning)
3877 "enumeral and non-enumeral type in conditional expression");
3880 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3881 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3885 --The second and third operands have pointer type, or one has
3886 pointer type and the other is a null pointer constant; pointer
3887 conversions (_conv.ptr_) and qualification conversions
3888 (_conv.qual_) are performed to bring them to their composite
3889 pointer type (_expr.rel_). The result is of the composite
3892 --The second and third operands have pointer to member type, or
3893 one has pointer to member type and the other is a null pointer
3894 constant; pointer to member conversions (_conv.mem_) and
3895 qualification conversions (_conv.qual_) are performed to bring
3896 them to a common type, whose cv-qualification shall match the
3897 cv-qualification of either the second or the third operand.
3898 The result is of the common type. */
3899 else if ((null_ptr_cst_p (arg2)
3900 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3901 || (null_ptr_cst_p (arg3)
3902 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3903 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3904 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3905 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3907 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3908 arg3, "conditional expression",
3910 if (result_type == error_mark_node)
3911 return error_mark_node;
3912 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3913 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3918 if (complain & tf_error)
3919 error ("operands to ?: have different types %qT and %qT",
3920 arg2_type, arg3_type);
3921 return error_mark_node;
3925 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3927 /* We can't use result_type below, as fold might have returned a
3932 /* Expand both sides into the same slot, hopefully the target of
3933 the ?: expression. We used to check for TARGET_EXPRs here,
3934 but now we sometimes wrap them in NOP_EXPRs so the test would
3936 if (CLASS_TYPE_P (TREE_TYPE (result)))
3937 result = get_target_expr (result);
3938 /* If this expression is an rvalue, but might be mistaken for an
3939 lvalue, we must add a NON_LVALUE_EXPR. */
3940 result = rvalue (result);
3946 /* OPERAND is an operand to an expression. Perform necessary steps
3947 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3951 prep_operand (tree operand)
3955 if (CLASS_TYPE_P (TREE_TYPE (operand))
3956 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3957 /* Make sure the template type is instantiated now. */
3958 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3964 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3965 OVERLOAD) to the CANDIDATES, returning an updated list of
3966 CANDIDATES. The ARGS are the arguments provided to the call,
3967 without any implicit object parameter. This may change ARGS. The
3968 EXPLICIT_TARGS are explicit template arguments provided.
3969 TEMPLATE_ONLY is true if only template functions should be
3970 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
3971 add_function_candidate. */
3974 add_candidates (tree fns, const VEC(tree,gc) *args,
3975 tree explicit_targs, bool template_only,
3976 tree conversion_path, tree access_path,
3978 struct z_candidate **candidates)
3981 VEC(tree,gc) *non_static_args;
3984 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3985 /* Delay creating the implicit this parameter until it is needed. */
3986 non_static_args = NULL;
3987 first_arg = NULL_TREE;
3993 const VEC(tree,gc) *fn_args;
3995 fn = OVL_CURRENT (fns);
3996 /* Figure out which set of arguments to use. */
3997 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3999 /* If this function is a non-static member, prepend the implicit
4000 object parameter. */
4001 if (non_static_args == NULL)
4006 non_static_args = VEC_alloc (tree, gc,
4007 VEC_length (tree, args) - 1);
4008 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4009 VEC_quick_push (tree, non_static_args, arg);
4011 if (first_arg == NULL_TREE)
4012 first_arg = build_this (VEC_index (tree, args, 0));
4013 fn_first_arg = first_arg;
4014 fn_args = non_static_args;
4018 /* Otherwise, just use the list of arguments provided. */
4019 fn_first_arg = NULL_TREE;
4023 if (TREE_CODE (fn) == TEMPLATE_DECL)
4024 add_template_candidate (candidates,
4035 else if (!template_only)
4036 add_function_candidate (candidates,
4044 fns = OVL_NEXT (fns);
4048 /* Even unsigned enum types promote to signed int. We don't want to
4049 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4050 original argument and ARG is the argument after any conversions
4051 have been applied. We set TREE_NO_WARNING if we have added a cast
4052 from an unsigned enum type to a signed integer type. */
4055 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4057 if (orig_arg != NULL_TREE
4060 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4061 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4062 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4063 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4064 TREE_NO_WARNING (arg) = 1;
4068 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4069 bool *overloaded_p, tsubst_flags_t complain)
4071 tree orig_arg1 = arg1;
4072 tree orig_arg2 = arg2;
4073 tree orig_arg3 = arg3;
4074 struct z_candidate *candidates = 0, *cand;
4075 VEC(tree,gc) *arglist;
4078 tree result = NULL_TREE;
4079 bool result_valid_p = false;
4080 enum tree_code code2 = NOP_EXPR;
4081 enum tree_code code_orig_arg1 = ERROR_MARK;
4082 enum tree_code code_orig_arg2 = ERROR_MARK;
4088 if (error_operand_p (arg1)
4089 || error_operand_p (arg2)
4090 || error_operand_p (arg3))
4091 return error_mark_node;
4093 if (code == MODIFY_EXPR)
4095 code2 = TREE_CODE (arg3);
4097 fnname = ansi_assopname (code2);
4100 fnname = ansi_opname (code);
4102 arg1 = prep_operand (arg1);
4108 case VEC_DELETE_EXPR:
4110 /* Use build_op_new_call and build_op_delete_call instead. */
4114 /* Use build_op_call instead. */
4117 case TRUTH_ORIF_EXPR:
4118 case TRUTH_ANDIF_EXPR:
4119 case TRUTH_AND_EXPR:
4121 /* These are saved for the sake of warn_logical_operator. */
4122 code_orig_arg1 = TREE_CODE (arg1);
4123 code_orig_arg2 = TREE_CODE (arg2);
4129 arg2 = prep_operand (arg2);
4130 arg3 = prep_operand (arg3);
4132 if (code == COND_EXPR)
4134 if (arg2 == NULL_TREE
4135 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
4136 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
4137 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
4138 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
4141 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4142 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4145 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4146 arg2 = integer_zero_node;
4148 arglist = VEC_alloc (tree, gc, 3);
4149 VEC_quick_push (tree, arglist, arg1);
4150 if (arg2 != NULL_TREE)
4151 VEC_quick_push (tree, arglist, arg2);
4152 if (arg3 != NULL_TREE)
4153 VEC_quick_push (tree, arglist, arg3);
4155 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4156 p = conversion_obstack_alloc (0);
4158 /* Add namespace-scope operators to the list of functions to
4160 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4161 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4162 flags, &candidates);
4163 /* Add class-member operators to the candidate set. */
4164 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4168 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4169 if (fns == error_mark_node)
4171 result = error_mark_node;
4172 goto user_defined_result_ready;
4175 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4177 BASELINK_BINFO (fns),
4178 TYPE_BINFO (TREE_TYPE (arg1)),
4179 flags, &candidates);
4182 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
4183 to know about two args; a builtin candidate will always have a first
4184 parameter of type bool. We'll handle that in
4185 build_builtin_candidate. */
4186 if (code == COND_EXPR)
4196 args[2] = NULL_TREE;
4199 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4205 /* For these, the built-in candidates set is empty
4206 [over.match.oper]/3. We don't want non-strict matches
4207 because exact matches are always possible with built-in
4208 operators. The built-in candidate set for COMPONENT_REF
4209 would be empty too, but since there are no such built-in
4210 operators, we accept non-strict matches for them. */
4215 strict_p = pedantic;
4219 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4224 case POSTINCREMENT_EXPR:
4225 case POSTDECREMENT_EXPR:
4226 /* Don't try anything fancy if we're not allowed to produce
4228 if (!(complain & tf_error))
4229 return error_mark_node;
4231 /* Look for an `operator++ (int)'. If they didn't have
4232 one, then we fall back to the old way of doing things. */
4233 if (flags & LOOKUP_COMPLAIN)
4234 permerror (input_location, "no %<%D(int)%> declared for postfix %qs, "
4235 "trying prefix operator instead",
4237 operator_name_info[code].name);
4238 if (code == POSTINCREMENT_EXPR)
4239 code = PREINCREMENT_EXPR;
4241 code = PREDECREMENT_EXPR;
4242 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4243 overloaded_p, complain);
4246 /* The caller will deal with these. */
4251 result_valid_p = true;
4255 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4257 /* If one of the arguments of the operator represents
4258 an invalid use of member function pointer, try to report
4259 a meaningful error ... */
4260 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4261 || invalid_nonstatic_memfn_p (arg2, tf_error)
4262 || invalid_nonstatic_memfn_p (arg3, tf_error))
4263 /* We displayed the error message. */;
4266 /* ... Otherwise, report the more generic
4267 "no matching operator found" error */
4268 op_error (code, code2, arg1, arg2, arg3, "no match");
4269 print_z_candidates (candidates);
4272 result = error_mark_node;
4278 cand = tourney (candidates);
4281 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4283 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4284 print_z_candidates (candidates);
4286 result = error_mark_node;
4288 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4291 *overloaded_p = true;
4293 if (resolve_args (arglist) == NULL)
4294 result = error_mark_node;
4296 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4300 /* Give any warnings we noticed during overload resolution. */
4301 if (cand->warnings && (complain & tf_warning))
4303 struct candidate_warning *w;
4304 for (w = cand->warnings; w; w = w->next)
4305 joust (cand, w->loser, 1);
4308 /* Check for comparison of different enum types. */
4317 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4318 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4319 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4320 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4321 && (complain & tf_warning))
4323 warning (OPT_Wenum_compare,
4324 "comparison between %q#T and %q#T",
4325 TREE_TYPE (arg1), TREE_TYPE (arg2));
4332 /* We need to strip any leading REF_BIND so that bitfields
4333 don't cause errors. This should not remove any important
4334 conversions, because builtins don't apply to class
4335 objects directly. */
4336 conv = cand->convs[0];
4337 if (conv->kind == ck_ref_bind)
4338 conv = conv->u.next;
4339 arg1 = convert_like (conv, arg1, complain);
4343 /* We need to call warn_logical_operator before
4344 converting arg2 to a boolean_type. */
4345 if (complain & tf_warning)
4346 warn_logical_operator (input_location, code, boolean_type_node,
4347 code_orig_arg1, arg1,
4348 code_orig_arg2, arg2);
4350 conv = cand->convs[1];
4351 if (conv->kind == ck_ref_bind)
4352 conv = conv->u.next;
4353 arg2 = convert_like (conv, arg2, complain);
4357 conv = cand->convs[2];
4358 if (conv->kind == ck_ref_bind)
4359 conv = conv->u.next;
4360 arg3 = convert_like (conv, arg3, complain);
4366 user_defined_result_ready:
4368 /* Free all the conversions we allocated. */
4369 obstack_free (&conversion_obstack, p);
4371 if (result || result_valid_p)
4375 avoid_sign_compare_warnings (orig_arg1, arg1);
4376 avoid_sign_compare_warnings (orig_arg2, arg2);
4377 avoid_sign_compare_warnings (orig_arg3, arg3);
4382 return cp_build_modify_expr (arg1, code2, arg2, complain);
4385 return cp_build_indirect_ref (arg1, "unary *", complain);
4387 case TRUTH_ANDIF_EXPR:
4388 case TRUTH_ORIF_EXPR:
4389 case TRUTH_AND_EXPR:
4391 warn_logical_operator (input_location, code, boolean_type_node,
4392 code_orig_arg1, arg1, code_orig_arg2, arg2);
4397 case TRUNC_DIV_EXPR:
4408 case TRUNC_MOD_EXPR:
4412 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4414 case UNARY_PLUS_EXPR:
4417 case TRUTH_NOT_EXPR:
4418 case PREINCREMENT_EXPR:
4419 case POSTINCREMENT_EXPR:
4420 case PREDECREMENT_EXPR:
4421 case POSTDECREMENT_EXPR:
4424 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4427 return build_array_ref (input_location, arg1, arg2);
4430 return build_conditional_expr (arg1, arg2, arg3, complain);
4433 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4437 /* The caller will deal with these. */
4449 /* Build a call to operator delete. This has to be handled very specially,
4450 because the restrictions on what signatures match are different from all
4451 other call instances. For a normal delete, only a delete taking (void *)
4452 or (void *, size_t) is accepted. For a placement delete, only an exact
4453 match with the placement new is accepted.
4455 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4456 ADDR is the pointer to be deleted.
4457 SIZE is the size of the memory block to be deleted.
4458 GLOBAL_P is true if the delete-expression should not consider
4459 class-specific delete operators.
4460 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4462 If this call to "operator delete" is being generated as part to
4463 deallocate memory allocated via a new-expression (as per [expr.new]
4464 which requires that if the initialization throws an exception then
4465 we call a deallocation function), then ALLOC_FN is the allocation
4469 build_op_delete_call (enum tree_code code, tree addr, tree size,
4470 bool global_p, tree placement,
4473 tree fn = NULL_TREE;
4474 tree fns, fnname, argtypes, type;
4477 if (addr == error_mark_node)
4478 return error_mark_node;
4480 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4482 fnname = ansi_opname (code);
4484 if (CLASS_TYPE_P (type)
4485 && COMPLETE_TYPE_P (complete_type (type))
4489 If the result of the lookup is ambiguous or inaccessible, or if
4490 the lookup selects a placement deallocation function, the
4491 program is ill-formed.
4493 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4495 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4496 if (fns == error_mark_node)
4497 return error_mark_node;
4502 if (fns == NULL_TREE)
4503 fns = lookup_name_nonclass (fnname);
4505 /* Strip const and volatile from addr. */
4506 addr = cp_convert (ptr_type_node, addr);
4510 /* Get the parameter types for the allocation function that is
4512 gcc_assert (alloc_fn != NULL_TREE);
4513 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4517 /* First try it without the size argument. */
4518 argtypes = void_list_node;
4521 /* We make two tries at finding a matching `operator delete'. On
4522 the first pass, we look for a one-operator (or placement)
4523 operator delete. If we're not doing placement delete, then on
4524 the second pass we look for a two-argument delete. */
4525 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4527 /* Go through the `operator delete' functions looking for one
4528 with a matching type. */
4529 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4535 /* The first argument must be "void *". */
4536 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4537 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4540 /* On the first pass, check the rest of the arguments. */
4546 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4554 /* On the second pass, look for a function with exactly two
4555 arguments: "void *" and "size_t". */
4557 /* For "operator delete(void *, ...)" there will be
4558 no second argument, but we will not get an exact
4561 && same_type_p (TREE_VALUE (t), size_type_node)
4562 && TREE_CHAIN (t) == void_list_node)
4566 /* If we found a match, we're done. */
4571 /* If we have a matching function, call it. */
4574 /* Make sure we have the actual function, and not an
4576 fn = OVL_CURRENT (fn);
4578 /* If the FN is a member function, make sure that it is
4580 if (DECL_CLASS_SCOPE_P (fn))
4581 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4585 /* The placement args might not be suitable for overload
4586 resolution at this point, so build the call directly. */
4587 int nargs = call_expr_nargs (placement);
4588 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4591 for (i = 1; i < nargs; i++)
4592 argarray[i] = CALL_EXPR_ARG (placement, i);
4594 return build_cxx_call (fn, nargs, argarray);
4599 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4600 VEC_quick_push (tree, args, addr);
4602 VEC_quick_push (tree, args, size);
4603 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4604 VEC_free (tree, gc, args);
4611 If no unambiguous matching deallocation function can be found,
4612 propagating the exception does not cause the object's memory to
4617 warning (0, "no corresponding deallocation function for %qD",
4622 error ("no suitable %<operator %s%> for %qT",
4623 operator_name_info[(int)code].name, type);
4624 return error_mark_node;
4627 /* If the current scope isn't allowed to access DECL along
4628 BASETYPE_PATH, give an error. The most derived class in
4629 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4630 the declaration to use in the error diagnostic. */
4633 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4635 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4637 if (!accessible_p (basetype_path, decl, true))
4639 if (TREE_PRIVATE (decl))
4640 error ("%q+#D is private", diag_decl);
4641 else if (TREE_PROTECTED (decl))
4642 error ("%q+#D is protected", diag_decl);
4644 error ("%q+#D is inaccessible", diag_decl);
4645 error ("within this context");
4652 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4653 bitwise or of LOOKUP_* values. If any errors are warnings are
4654 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4655 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4659 build_temp (tree expr, tree type, int flags,
4660 diagnostic_t *diagnostic_kind)
4665 savew = warningcount, savee = errorcount;
4666 args = make_tree_vector_single (expr);
4667 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4668 &args, type, flags, tf_warning_or_error);
4669 release_tree_vector (args);
4670 if (warningcount > savew)
4671 *diagnostic_kind = DK_WARNING;
4672 else if (errorcount > savee)
4673 *diagnostic_kind = DK_ERROR;
4675 *diagnostic_kind = DK_UNSPECIFIED;
4679 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4680 EXPR is implicitly converted to type TOTYPE.
4681 FN and ARGNUM are used for diagnostics. */
4684 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4686 tree t = non_reference (totype);
4688 /* Issue warnings about peculiar, but valid, uses of NULL. */
4689 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4692 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4695 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4698 /* Issue warnings if "false" is converted to a NULL pointer */
4699 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4700 warning (OPT_Wconversion,
4701 "converting %<false%> to pointer type for argument %P of %qD",
4705 /* Perform the conversions in CONVS on the expression EXPR. FN and
4706 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4707 indicates the `this' argument of a method. INNER is nonzero when
4708 being called to continue a conversion chain. It is negative when a
4709 reference binding will be applied, positive otherwise. If
4710 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4711 conversions will be emitted if appropriate. If C_CAST_P is true,
4712 this conversion is coming from a C-style cast; in that case,
4713 conversions to inaccessible bases are permitted. */
4716 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4717 int inner, bool issue_conversion_warnings,
4718 bool c_cast_p, tsubst_flags_t complain)
4720 tree totype = convs->type;
4721 diagnostic_t diag_kind;
4725 && convs->kind != ck_user
4726 && convs->kind != ck_list
4727 && convs->kind != ck_ambig
4728 && convs->kind != ck_ref_bind
4729 && convs->kind != ck_rvalue
4730 && convs->kind != ck_base)
4732 conversion *t = convs;
4734 /* Give a helpful error if this is bad because of excess braces. */
4735 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
4736 && SCALAR_TYPE_P (totype)
4737 && CONSTRUCTOR_NELTS (expr) > 0
4738 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
4739 permerror (input_location, "too many braces around initializer for %qT", totype);
4741 for (; t; t = convs->u.next)
4743 if (t->kind == ck_user || !t->bad_p)
4745 expr = convert_like_real (t, expr, fn, argnum, 1,
4746 /*issue_conversion_warnings=*/false,
4751 else if (t->kind == ck_ambig)
4752 return convert_like_real (t, expr, fn, argnum, 1,
4753 /*issue_conversion_warnings=*/false,
4756 else if (t->kind == ck_identity)
4759 if (complain & tf_error)
4761 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4763 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4766 return error_mark_node;
4768 return cp_convert (totype, expr);
4771 if (issue_conversion_warnings && (complain & tf_warning))
4772 conversion_null_warnings (totype, expr, fn, argnum);
4774 switch (convs->kind)
4778 struct z_candidate *cand = convs->cand;
4779 tree convfn = cand->fn;
4782 /* When converting from an init list we consider explicit
4783 constructors, but actually trying to call one is an error. */
4784 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4786 if (complain & tf_error)
4787 error ("converting to %qT from initializer list would use "
4788 "explicit constructor %qD", totype, convfn);
4790 return error_mark_node;
4793 /* Set user_conv_p on the argument conversions, so rvalue/base
4794 handling knows not to allow any more UDCs. */
4795 for (i = 0; i < cand->num_convs; ++i)
4796 cand->convs[i]->user_conv_p = true;
4798 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4800 /* If this is a constructor or a function returning an aggr type,
4801 we need to build up a TARGET_EXPR. */
4802 if (DECL_CONSTRUCTOR_P (convfn))
4804 expr = build_cplus_new (totype, expr);
4806 /* Remember that this was list-initialization. */
4807 if (convs->check_narrowing)
4808 TARGET_EXPR_LIST_INIT_P (expr) = true;
4814 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
4816 int nelts = CONSTRUCTOR_NELTS (expr);
4818 expr = integer_zero_node;
4819 else if (nelts == 1)
4820 expr = CONSTRUCTOR_ELT (expr, 0)->value;
4825 if (type_unknown_p (expr))
4826 expr = instantiate_type (totype, expr, complain);
4827 /* Convert a constant to its underlying value, unless we are
4828 about to bind it to a reference, in which case we need to
4829 leave it as an lvalue. */
4832 expr = decl_constant_value (expr);
4833 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4834 /* If __null has been converted to an integer type, we do not
4835 want to warn about uses of EXPR as an integer, rather than
4837 expr = build_int_cst (totype, 0);
4841 /* Call build_user_type_conversion again for the error. */
4842 return build_user_type_conversion
4843 (totype, convs->u.expr, LOOKUP_NORMAL);
4847 /* Conversion to std::initializer_list<T>. */
4848 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4849 tree new_ctor = build_constructor (init_list_type_node, NULL);
4850 unsigned len = CONSTRUCTOR_NELTS (expr);
4852 VEC(tree,gc) *parms;
4855 /* Convert all the elements. */
4856 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4858 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4859 1, false, false, complain);
4860 if (sub == error_mark_node)
4862 check_narrowing (TREE_TYPE (sub), val);
4863 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4865 /* Build up the array. */
4866 elttype = cp_build_qualified_type
4867 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4868 array = build_array_of_n_type (elttype, len);
4869 array = finish_compound_literal (array, new_ctor);
4871 parms = make_tree_vector ();
4872 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4873 VEC_safe_push (tree, gc, parms, size_int (len));
4874 /* Call the private constructor. */
4875 push_deferring_access_checks (dk_no_check);
4876 new_ctor = build_special_member_call
4877 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4878 release_tree_vector (parms);
4879 pop_deferring_access_checks ();
4880 return build_cplus_new (totype, new_ctor);
4884 return get_target_expr (digest_init (totype, expr));
4890 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4891 convs->kind == ck_ref_bind ? -1 : 1,
4892 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4895 if (expr == error_mark_node)
4896 return error_mark_node;
4898 switch (convs->kind)
4901 expr = convert_bitfield_to_declared_type (expr);
4902 if (! MAYBE_CLASS_TYPE_P (totype))
4904 /* Else fall through. */
4906 if (convs->kind == ck_base && !convs->need_temporary_p)
4908 /* We are going to bind a reference directly to a base-class
4909 subobject of EXPR. */
4910 /* Build an expression for `*((base*) &expr)'. */
4911 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4912 expr = convert_to_base (expr, build_pointer_type (totype),
4913 !c_cast_p, /*nonnull=*/true);
4914 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4918 /* Copy-initialization where the cv-unqualified version of the source
4919 type is the same class as, or a derived class of, the class of the
4920 destination [is treated as direct-initialization]. [dcl.init] */
4921 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4922 if (convs->user_conv_p)
4923 /* This conversion is being done in the context of a user-defined
4924 conversion (i.e. the second step of copy-initialization), so
4925 don't allow any more. */
4926 flags |= LOOKUP_NO_CONVERSION;
4927 expr = build_temp (expr, totype, flags, &diag_kind);
4928 if (diag_kind && fn)
4930 if ((complain & tf_error))
4931 emit_diagnostic (diag_kind, input_location, 0,
4932 " initializing argument %P of %qD", argnum, fn);
4933 else if (diag_kind == DK_ERROR)
4934 return error_mark_node;
4936 return build_cplus_new (totype, expr);
4940 tree ref_type = totype;
4942 /* If necessary, create a temporary.
4944 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4945 that need temporaries, even when their types are reference
4946 compatible with the type of reference being bound, so the
4947 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
4949 if (convs->need_temporary_p
4950 || TREE_CODE (expr) == CONSTRUCTOR
4951 || TREE_CODE (expr) == VA_ARG_EXPR)
4953 tree type = convs->u.next->type;
4954 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4956 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4957 && !TYPE_REF_IS_RVALUE (ref_type))
4959 if (complain & tf_error)
4961 /* If the reference is volatile or non-const, we
4962 cannot create a temporary. */
4963 if (lvalue & clk_bitfield)
4964 error ("cannot bind bitfield %qE to %qT",
4966 else if (lvalue & clk_packed)
4967 error ("cannot bind packed field %qE to %qT",
4970 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4972 return error_mark_node;
4974 /* If the source is a packed field, and we must use a copy
4975 constructor, then building the target expr will require
4976 binding the field to the reference parameter to the
4977 copy constructor, and we'll end up with an infinite
4978 loop. If we can use a bitwise copy, then we'll be
4980 if ((lvalue & clk_packed)
4981 && CLASS_TYPE_P (type)
4982 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4984 if (complain & tf_error)
4985 error ("cannot bind packed field %qE to %qT",
4987 return error_mark_node;
4989 if (lvalue & clk_bitfield)
4991 expr = convert_bitfield_to_declared_type (expr);
4992 expr = fold_convert (type, expr);
4994 expr = build_target_expr_with_type (expr, type);
4997 /* Take the address of the thing to which we will bind the
4999 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
5000 if (expr == error_mark_node)
5001 return error_mark_node;
5003 /* Convert it to a pointer to the type referred to by the
5004 reference. This will adjust the pointer if a derived to
5005 base conversion is being performed. */
5006 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5008 /* Convert the pointer to the desired reference type. */
5009 return build_nop (ref_type, expr);
5013 return decay_conversion (expr);
5016 /* Warn about deprecated conversion if appropriate. */
5017 string_conv_p (totype, expr, 1);
5022 expr = convert_to_base (expr, totype, !c_cast_p,
5024 return build_nop (totype, expr);
5027 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5034 if (convs->check_narrowing)
5035 check_narrowing (totype, expr);
5037 if (issue_conversion_warnings && (complain & tf_warning))
5038 expr = convert_and_check (totype, expr);
5040 expr = convert (totype, expr);
5045 /* Build a call to __builtin_trap. */
5048 call_builtin_trap (void)
5050 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
5052 gcc_assert (fn != NULL);
5053 fn = build_call_n (fn, 0);
5057 /* ARG is being passed to a varargs function. Perform any conversions
5058 required. Return the converted value. */
5061 convert_arg_to_ellipsis (tree arg)
5065 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5066 standard conversions are performed. */
5067 arg = decay_conversion (arg);
5070 If the argument has integral or enumeration type that is subject
5071 to the integral promotions (_conv.prom_), or a floating point
5072 type that is subject to the floating point promotion
5073 (_conv.fpprom_), the value of the argument is converted to the
5074 promoted type before the call. */
5075 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5076 && (TYPE_PRECISION (TREE_TYPE (arg))
5077 < TYPE_PRECISION (double_type_node)))
5078 arg = convert_to_real (double_type_node, arg);
5079 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5080 arg = perform_integral_promotions (arg);
5082 arg = require_complete_type (arg);
5084 if (arg != error_mark_node
5085 && !pod_type_p (TREE_TYPE (arg)))
5087 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
5088 here and do a bitwise copy, but now cp_expr_size will abort if we
5090 If the call appears in the context of a sizeof expression,
5091 there is no need to emit a warning, since the expression won't be
5092 evaluated. We keep the builtin_trap just as a safety check. */
5093 if (cp_unevaluated_operand == 0)
5094 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
5095 "call will abort at runtime", TREE_TYPE (arg));
5096 arg = call_builtin_trap ();
5097 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
5104 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5107 build_x_va_arg (tree expr, tree type)
5109 if (processing_template_decl)
5110 return build_min (VA_ARG_EXPR, type, expr);
5112 type = complete_type_or_else (type, NULL_TREE);
5114 if (expr == error_mark_node || !type)
5115 return error_mark_node;
5117 if (! pod_type_p (type))
5119 /* Remove reference types so we don't ICE later on. */
5120 tree type1 = non_reference (type);
5121 /* Undefined behavior [expr.call] 5.2.2/7. */
5122 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
5123 "call will abort at runtime", type);
5124 expr = convert (build_pointer_type (type1), null_node);
5125 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
5126 call_builtin_trap (), expr);
5127 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
5131 return build_va_arg (input_location, expr, type);
5134 /* TYPE has been given to va_arg. Apply the default conversions which
5135 would have happened when passed via ellipsis. Return the promoted
5136 type, or the passed type if there is no change. */
5139 cxx_type_promotes_to (tree type)
5143 /* Perform the array-to-pointer and function-to-pointer
5145 type = type_decays_to (type);
5147 promote = type_promotes_to (type);
5148 if (same_type_p (type, promote))
5154 /* ARG is a default argument expression being passed to a parameter of
5155 the indicated TYPE, which is a parameter to FN. Do any required
5156 conversions. Return the converted value. */
5158 static GTY(()) VEC(tree,gc) *default_arg_context;
5161 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5166 /* If the ARG is an unparsed default argument expression, the
5167 conversion cannot be performed. */
5168 if (TREE_CODE (arg) == DEFAULT_ARG)
5170 error ("the default argument for parameter %d of %qD has "
5171 "not yet been parsed",
5173 return error_mark_node;
5176 /* Detect recursion. */
5177 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5180 error ("recursive evaluation of default argument for %q#D", fn);
5181 return error_mark_node;
5183 VEC_safe_push (tree, gc, default_arg_context, fn);
5185 if (fn && DECL_TEMPLATE_INFO (fn))
5186 arg = tsubst_default_argument (fn, type, arg);
5192 The names in the expression are bound, and the semantic
5193 constraints are checked, at the point where the default
5194 expressions appears.
5196 we must not perform access checks here. */
5197 push_deferring_access_checks (dk_no_check);
5198 arg = break_out_target_exprs (arg);
5199 if (TREE_CODE (arg) == CONSTRUCTOR)
5201 arg = digest_init (type, arg);
5202 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5203 "default argument", fn, parmnum,
5204 tf_warning_or_error);
5208 /* We must make a copy of ARG, in case subsequent processing
5209 alters any part of it. For example, during gimplification a
5210 cast of the form (T) &X::f (where "f" is a member function)
5211 will lead to replacing the PTRMEM_CST for &X::f with a
5212 VAR_DECL. We can avoid the copy for constants, since they
5213 are never modified in place. */
5214 if (!CONSTANT_CLASS_P (arg))
5215 arg = unshare_expr (arg);
5216 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5217 "default argument", fn, parmnum,
5218 tf_warning_or_error);
5219 arg = convert_for_arg_passing (type, arg);
5221 pop_deferring_access_checks();
5223 VEC_pop (tree, default_arg_context);
5228 /* Returns the type which will really be used for passing an argument of
5232 type_passed_as (tree type)
5234 /* Pass classes with copy ctors by invisible reference. */
5235 if (TREE_ADDRESSABLE (type))
5237 type = build_reference_type (type);
5238 /* There are no other pointers to this temporary. */
5239 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5241 else if (targetm.calls.promote_prototypes (type)
5242 && INTEGRAL_TYPE_P (type)
5243 && COMPLETE_TYPE_P (type)
5244 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5245 TYPE_SIZE (integer_type_node)))
5246 type = integer_type_node;
5251 /* Actually perform the appropriate conversion. */
5254 convert_for_arg_passing (tree type, tree val)
5258 /* If VAL is a bitfield, then -- since it has already been converted
5259 to TYPE -- it cannot have a precision greater than TYPE.
5261 If it has a smaller precision, we must widen it here. For
5262 example, passing "int f:3;" to a function expecting an "int" will
5263 not result in any conversion before this point.
5265 If the precision is the same we must not risk widening. For
5266 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5267 often have type "int", even though the C++ type for the field is
5268 "long long". If the value is being passed to a function
5269 expecting an "int", then no conversions will be required. But,
5270 if we call convert_bitfield_to_declared_type, the bitfield will
5271 be converted to "long long". */
5272 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5274 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5275 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5277 if (val == error_mark_node)
5279 /* Pass classes with copy ctors by invisible reference. */
5280 else if (TREE_ADDRESSABLE (type))
5281 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5282 else if (targetm.calls.promote_prototypes (type)
5283 && INTEGRAL_TYPE_P (type)
5284 && COMPLETE_TYPE_P (type)
5285 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5286 TYPE_SIZE (integer_type_node)))
5287 val = perform_integral_promotions (val);
5288 if (warn_missing_format_attribute)
5290 tree rhstype = TREE_TYPE (val);
5291 const enum tree_code coder = TREE_CODE (rhstype);
5292 const enum tree_code codel = TREE_CODE (type);
5293 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5295 && check_missing_format_attribute (type, rhstype))
5296 warning (OPT_Wmissing_format_attribute,
5297 "argument of function call might be a candidate for a format attribute");
5302 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5303 which no conversions at all should be done. This is true for some
5304 builtins which don't act like normal functions. */
5307 magic_varargs_p (tree fn)
5309 if (DECL_BUILT_IN (fn))
5310 switch (DECL_FUNCTION_CODE (fn))
5312 case BUILT_IN_CLASSIFY_TYPE:
5313 case BUILT_IN_CONSTANT_P:
5314 case BUILT_IN_NEXT_ARG:
5315 case BUILT_IN_VA_START:
5319 return lookup_attribute ("type generic",
5320 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5326 /* Subroutine of the various build_*_call functions. Overload resolution
5327 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5328 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5329 bitmask of various LOOKUP_* flags which apply to the call itself. */
5332 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5335 const VEC(tree,gc) *args = cand->args;
5336 tree first_arg = cand->first_arg;
5337 conversion **convs = cand->convs;
5339 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5344 unsigned int arg_index = 0;
5348 bool already_used = false;
5350 /* In a template, there is no need to perform all of the work that
5351 is normally done. We are only interested in the type of the call
5352 expression, i.e., the return type of the function. Any semantic
5353 errors will be deferred until the template is instantiated. */
5354 if (processing_template_decl)
5358 const tree *argarray;
5361 return_type = TREE_TYPE (TREE_TYPE (fn));
5362 nargs = VEC_length (tree, args);
5363 if (first_arg == NULL_TREE)
5364 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5372 alcarray = XALLOCAVEC (tree, nargs);
5373 alcarray[0] = first_arg;
5374 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5375 alcarray[ix + 1] = arg;
5376 argarray = alcarray;
5378 expr = build_call_array (return_type, build_addr_func (fn), nargs,
5380 if (TREE_THIS_VOLATILE (fn) && cfun)
5381 current_function_returns_abnormally = 1;
5382 if (!VOID_TYPE_P (return_type))
5383 require_complete_type (return_type);
5384 return convert_from_reference (expr);
5387 /* Give any warnings we noticed during overload resolution. */
5390 struct candidate_warning *w;
5391 for (w = cand->warnings; w; w = w->next)
5392 joust (cand, w->loser, 1);
5395 /* Make =delete work with SFINAE. */
5396 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5397 return error_mark_node;
5399 if (DECL_FUNCTION_MEMBER_P (fn))
5401 /* If FN is a template function, two cases must be considered.
5406 template <class T> void f();
5408 template <class T> struct B {
5412 struct C : A, B<int> {
5414 using B<int>::g; // #2
5417 In case #1 where `A::f' is a member template, DECL_ACCESS is
5418 recorded in the primary template but not in its specialization.
5419 We check access of FN using its primary template.
5421 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5422 because it is a member of class template B, DECL_ACCESS is
5423 recorded in the specialization `B<int>::g'. We cannot use its
5424 primary template because `B<T>::g' and `B<int>::g' may have
5425 different access. */
5426 if (DECL_TEMPLATE_INFO (fn)
5427 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5428 perform_or_defer_access_check (cand->access_path,
5429 DECL_TI_TEMPLATE (fn), fn);
5431 perform_or_defer_access_check (cand->access_path, fn, fn);
5434 /* Find maximum size of vector to hold converted arguments. */
5435 parmlen = list_length (parm);
5436 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5437 if (parmlen > nargs)
5439 argarray = (tree *) alloca (nargs * sizeof (tree));
5441 /* The implicit parameters to a constructor are not considered by overload
5442 resolution, and must be of the proper type. */
5443 if (DECL_CONSTRUCTOR_P (fn))
5445 if (first_arg != NULL_TREE)
5447 argarray[j++] = first_arg;
5448 first_arg = NULL_TREE;
5452 argarray[j++] = VEC_index (tree, args, arg_index);
5455 parm = TREE_CHAIN (parm);
5456 /* We should never try to call the abstract constructor. */
5457 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5459 if (DECL_HAS_VTT_PARM_P (fn))
5461 argarray[j++] = VEC_index (tree, args, arg_index);
5463 parm = TREE_CHAIN (parm);
5466 /* Bypass access control for 'this' parameter. */
5467 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5469 tree parmtype = TREE_VALUE (parm);
5470 tree arg = (first_arg != NULL_TREE
5472 : VEC_index (tree, args, arg_index));
5473 tree argtype = TREE_TYPE (arg);
5477 if (convs[i]->bad_p)
5479 if (complain & tf_error)
5480 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5481 TREE_TYPE (argtype), fn);
5483 return error_mark_node;
5486 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5487 X is called for an object that is not of type X, or of a type
5488 derived from X, the behavior is undefined.
5490 So we can assume that anything passed as 'this' is non-null, and
5491 optimize accordingly. */
5492 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5493 /* Convert to the base in which the function was declared. */
5494 gcc_assert (cand->conversion_path != NULL_TREE);
5495 converted_arg = build_base_path (PLUS_EXPR,
5497 cand->conversion_path,
5499 /* Check that the base class is accessible. */
5500 if (!accessible_base_p (TREE_TYPE (argtype),
5501 BINFO_TYPE (cand->conversion_path), true))
5502 error ("%qT is not an accessible base of %qT",
5503 BINFO_TYPE (cand->conversion_path),
5504 TREE_TYPE (argtype));
5505 /* If fn was found by a using declaration, the conversion path
5506 will be to the derived class, not the base declaring fn. We
5507 must convert from derived to base. */
5508 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5509 TREE_TYPE (parmtype), ba_unique, NULL);
5510 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5513 argarray[j++] = converted_arg;
5514 parm = TREE_CHAIN (parm);
5515 if (first_arg != NULL_TREE)
5516 first_arg = NULL_TREE;
5523 gcc_assert (first_arg == NULL_TREE);
5524 for (; arg_index < VEC_length (tree, args) && parm;
5525 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5527 tree type = TREE_VALUE (parm);
5531 /* Don't make a copy here if build_call is going to. */
5532 if (conv->kind == ck_rvalue
5533 && COMPLETE_TYPE_P (complete_type (type))
5534 && !TREE_ADDRESSABLE (type))
5535 conv = conv->u.next;
5537 val = convert_like_with_context
5538 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5541 val = convert_for_arg_passing (type, val);
5542 if (val == error_mark_node)
5543 return error_mark_node;
5545 argarray[j++] = val;
5548 /* Default arguments */
5549 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5550 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5551 TREE_PURPOSE (parm),
5554 for (; arg_index < VEC_length (tree, args); ++arg_index)
5556 tree a = VEC_index (tree, args, arg_index);
5557 if (magic_varargs_p (fn))
5558 /* Do no conversions for magic varargs. */;
5560 a = convert_arg_to_ellipsis (a);
5564 gcc_assert (j <= nargs);
5567 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5568 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5570 /* Avoid actually calling copy constructors and copy assignment operators,
5573 if (! flag_elide_constructors)
5574 /* Do things the hard way. */;
5575 else if (cand->num_convs == 1
5576 && (DECL_COPY_CONSTRUCTOR_P (fn)
5577 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5580 tree arg = argarray[num_artificial_parms_for (fn)];
5583 /* Pull out the real argument, disregarding const-correctness. */
5585 while (CONVERT_EXPR_P (targ)
5586 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5587 targ = TREE_OPERAND (targ, 0);
5588 if (TREE_CODE (targ) == ADDR_EXPR)
5590 targ = TREE_OPERAND (targ, 0);
5591 if (!same_type_ignoring_top_level_qualifiers_p
5592 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5601 arg = cp_build_indirect_ref (arg, 0, complain);
5603 if (TREE_CODE (arg) == TARGET_EXPR
5604 && TARGET_EXPR_LIST_INIT_P (arg))
5606 /* Copy-list-initialization doesn't require the copy constructor
5609 /* [class.copy]: the copy constructor is implicitly defined even if
5610 the implementation elided its use. */
5611 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5614 already_used = true;
5617 /* If we're creating a temp and we already have one, don't create a
5618 new one. If we're not creating a temp but we get one, use
5619 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5620 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5621 temp or an INIT_EXPR otherwise. */
5622 fa = (cand->first_arg != NULL_TREE
5624 : VEC_index (tree, args, 0));
5625 if (integer_zerop (fa))
5627 if (TREE_CODE (arg) == TARGET_EXPR)
5629 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5630 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5632 else if (TREE_CODE (arg) == TARGET_EXPR
5633 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5634 && !move_fn_p (fn)))
5636 tree to = stabilize_reference (cp_build_indirect_ref (fa, 0,
5639 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5643 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5645 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5647 tree to = stabilize_reference
5648 (cp_build_indirect_ref (argarray[0], 0, complain));
5649 tree type = TREE_TYPE (to);
5650 tree as_base = CLASSTYPE_AS_BASE (type);
5651 tree arg = argarray[1];
5653 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5655 arg = cp_build_indirect_ref (arg, 0, complain);
5656 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5660 /* We must only copy the non-tail padding parts.
5661 Use __builtin_memcpy for the bitwise copy.
5662 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5663 instead of an explicit call to memcpy. */
5665 tree arg0, arg1, arg2, t;
5666 tree test = NULL_TREE;
5668 arg2 = TYPE_SIZE_UNIT (as_base);
5670 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5672 if (!(optimize && flag_tree_ter))
5674 /* When TER is off get_pointer_alignment returns 0, so a call
5675 to __builtin_memcpy is expanded as a call to memcpy, which
5676 is invalid with identical args. When TER is on it is
5677 expanded as a block move, which should be safe. */
5678 arg0 = save_expr (arg0);
5679 arg1 = save_expr (arg1);
5680 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5682 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5683 t = build_call_n (t, 3, arg0, arg1, arg2);
5685 t = convert (TREE_TYPE (arg0), t);
5687 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5688 val = cp_build_indirect_ref (t, 0, complain);
5689 TREE_NO_WARNING (val) = 1;
5698 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5701 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5704 gcc_assert (binfo && binfo != error_mark_node);
5706 /* Warn about deprecated virtual functions now, since we're about
5707 to throw away the decl. */
5708 if (TREE_DEPRECATED (fn))
5709 warn_deprecated_use (fn, NULL_TREE);
5711 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5712 if (TREE_SIDE_EFFECTS (argarray[0]))
5713 argarray[0] = save_expr (argarray[0]);
5714 t = build_pointer_type (TREE_TYPE (fn));
5715 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5716 fn = build_java_interface_fn_ref (fn, argarray[0]);
5718 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5722 fn = build_addr_func (fn);
5724 return build_cxx_call (fn, nargs, argarray);
5727 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5728 This function performs no overload resolution, conversion, or other
5729 high-level operations. */
5732 build_cxx_call (tree fn, int nargs, tree *argarray)
5736 fn = build_call_a (fn, nargs, argarray);
5738 /* If this call might throw an exception, note that fact. */
5739 fndecl = get_callee_fndecl (fn);
5740 if ((!fndecl || !TREE_NOTHROW (fndecl))
5741 && at_function_scope_p ()
5743 cp_function_chain->can_throw = 1;
5745 /* Check that arguments to builtin functions match the expectations. */
5747 && DECL_BUILT_IN (fndecl)
5748 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5749 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5750 return error_mark_node;
5752 /* Some built-in function calls will be evaluated at compile-time in
5754 fn = fold_if_not_in_template (fn);
5756 if (VOID_TYPE_P (TREE_TYPE (fn)))
5759 fn = require_complete_type (fn);
5760 if (fn == error_mark_node)
5761 return error_mark_node;
5763 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5764 fn = build_cplus_new (TREE_TYPE (fn), fn);
5765 return convert_from_reference (fn);
5768 static GTY(()) tree java_iface_lookup_fn;
5770 /* Make an expression which yields the address of the Java interface
5771 method FN. This is achieved by generating a call to libjava's
5772 _Jv_LookupInterfaceMethodIdx(). */
5775 build_java_interface_fn_ref (tree fn, tree instance)
5777 tree lookup_fn, method, idx;
5778 tree klass_ref, iface, iface_ref;
5781 if (!java_iface_lookup_fn)
5783 tree endlink = build_void_list_node ();
5784 tree t = tree_cons (NULL_TREE, ptr_type_node,
5785 tree_cons (NULL_TREE, ptr_type_node,
5786 tree_cons (NULL_TREE, java_int_type_node,
5788 java_iface_lookup_fn
5789 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5790 build_function_type (ptr_type_node, t),
5791 0, NOT_BUILT_IN, NULL, NULL_TREE);
5794 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5795 This is the first entry in the vtable. */
5796 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5797 tf_warning_or_error),
5800 /* Get the java.lang.Class pointer for the interface being called. */
5801 iface = DECL_CONTEXT (fn);
5802 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5803 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5804 || DECL_CONTEXT (iface_ref) != iface)
5806 error ("could not find class$ field in java interface type %qT",
5808 return error_mark_node;
5810 iface_ref = build_address (iface_ref);
5811 iface_ref = convert (build_pointer_type (iface), iface_ref);
5813 /* Determine the itable index of FN. */
5815 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5817 if (!DECL_VIRTUAL_P (method))
5823 idx = build_int_cst (NULL_TREE, i);
5825 lookup_fn = build1 (ADDR_EXPR,
5826 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5827 java_iface_lookup_fn);
5828 return build_call_nary (ptr_type_node, lookup_fn,
5829 3, klass_ref, iface_ref, idx);
5832 /* Returns the value to use for the in-charge parameter when making a
5833 call to a function with the indicated NAME.
5835 FIXME:Can't we find a neater way to do this mapping? */
5838 in_charge_arg_for_name (tree name)
5840 if (name == base_ctor_identifier
5841 || name == base_dtor_identifier)
5842 return integer_zero_node;
5843 else if (name == complete_ctor_identifier)
5844 return integer_one_node;
5845 else if (name == complete_dtor_identifier)
5846 return integer_two_node;
5847 else if (name == deleting_dtor_identifier)
5848 return integer_three_node;
5850 /* This function should only be called with one of the names listed
5856 /* Build a call to a constructor, destructor, or an assignment
5857 operator for INSTANCE, an expression with class type. NAME
5858 indicates the special member function to call; *ARGS are the
5859 arguments. ARGS may be NULL. This may change ARGS. BINFO
5860 indicates the base of INSTANCE that is to be passed as the `this'
5861 parameter to the member function called.
5863 FLAGS are the LOOKUP_* flags to use when processing the call.
5865 If NAME indicates a complete object constructor, INSTANCE may be
5866 NULL_TREE. In this case, the caller will call build_cplus_new to
5867 store the newly constructed object into a VAR_DECL. */
5870 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
5871 tree binfo, int flags, tsubst_flags_t complain)
5874 /* The type of the subobject to be constructed or destroyed. */
5876 VEC(tree,gc) *allocated = NULL;
5879 gcc_assert (name == complete_ctor_identifier
5880 || name == base_ctor_identifier
5881 || name == complete_dtor_identifier
5882 || name == base_dtor_identifier
5883 || name == deleting_dtor_identifier
5884 || name == ansi_assopname (NOP_EXPR));
5887 /* Resolve the name. */
5888 if (!complete_type_or_else (binfo, NULL_TREE))
5889 return error_mark_node;
5891 binfo = TYPE_BINFO (binfo);
5894 gcc_assert (binfo != NULL_TREE);
5896 class_type = BINFO_TYPE (binfo);
5898 /* Handle the special case where INSTANCE is NULL_TREE. */
5899 if (name == complete_ctor_identifier && !instance)
5901 instance = build_int_cst (build_pointer_type (class_type), 0);
5902 instance = build1 (INDIRECT_REF, class_type, instance);
5906 if (name == complete_dtor_identifier
5907 || name == base_dtor_identifier
5908 || name == deleting_dtor_identifier)
5909 gcc_assert (args == NULL || VEC_empty (tree, *args));
5911 /* Convert to the base class, if necessary. */
5912 if (!same_type_ignoring_top_level_qualifiers_p
5913 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5915 if (name != ansi_assopname (NOP_EXPR))
5916 /* For constructors and destructors, either the base is
5917 non-virtual, or it is virtual but we are doing the
5918 conversion from a constructor or destructor for the
5919 complete object. In either case, we can convert
5921 instance = convert_to_base_statically (instance, binfo);
5923 /* However, for assignment operators, we must convert
5924 dynamically if the base is virtual. */
5925 instance = build_base_path (PLUS_EXPR, instance,
5926 binfo, /*nonnull=*/1);
5930 gcc_assert (instance != NULL_TREE);
5932 fns = lookup_fnfields (binfo, name, 1);
5934 /* When making a call to a constructor or destructor for a subobject
5935 that uses virtual base classes, pass down a pointer to a VTT for
5937 if ((name == base_ctor_identifier
5938 || name == base_dtor_identifier)
5939 && CLASSTYPE_VBASECLASSES (class_type))
5944 /* If the current function is a complete object constructor
5945 or destructor, then we fetch the VTT directly.
5946 Otherwise, we look it up using the VTT we were given. */
5947 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5948 vtt = decay_conversion (vtt);
5949 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5950 build2 (EQ_EXPR, boolean_type_node,
5951 current_in_charge_parm, integer_zero_node),
5954 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5955 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5956 BINFO_SUBVTT_INDEX (binfo));
5960 allocated = make_tree_vector ();
5964 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
5967 ret = build_new_method_call (instance, fns, args,
5968 TYPE_BINFO (BINFO_TYPE (binfo)),
5972 if (allocated != NULL)
5973 release_tree_vector (allocated);
5978 /* Return the NAME, as a C string. The NAME indicates a function that
5979 is a member of TYPE. *FREE_P is set to true if the caller must
5980 free the memory returned.
5982 Rather than go through all of this, we should simply set the names
5983 of constructors and destructors appropriately, and dispense with
5984 ctor_identifier, dtor_identifier, etc. */
5987 name_as_c_string (tree name, tree type, bool *free_p)
5991 /* Assume that we will not allocate memory. */
5993 /* Constructors and destructors are special. */
5994 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5997 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
5998 /* For a destructor, add the '~'. */
5999 if (name == complete_dtor_identifier
6000 || name == base_dtor_identifier
6001 || name == deleting_dtor_identifier)
6003 pretty_name = concat ("~", pretty_name, NULL);
6004 /* Remember that we need to free the memory allocated. */
6008 else if (IDENTIFIER_TYPENAME_P (name))
6010 pretty_name = concat ("operator ",
6011 type_as_string_translate (TREE_TYPE (name),
6012 TFF_PLAIN_IDENTIFIER),
6014 /* Remember that we need to free the memory allocated. */
6018 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6023 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6024 be set, upon return, to the function called. ARGS may be NULL.
6025 This may change ARGS. */
6028 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
6029 tree conversion_path, int flags,
6030 tree *fn_p, tsubst_flags_t complain)
6032 struct z_candidate *candidates = 0, *cand;
6033 tree explicit_targs = NULL_TREE;
6034 tree basetype = NULL_TREE;
6037 tree first_mem_arg = NULL_TREE;
6040 bool skip_first_for_error;
6041 VEC(tree,gc) *user_args;
6045 int template_only = 0;
6049 VEC(tree,gc) *orig_args = NULL;
6052 gcc_assert (instance != NULL_TREE);
6054 /* We don't know what function we're going to call, yet. */
6058 if (error_operand_p (instance)
6059 || error_operand_p (fns))
6060 return error_mark_node;
6062 if (!BASELINK_P (fns))
6064 if (complain & tf_error)
6065 error ("call to non-function %qD", fns);
6066 return error_mark_node;
6069 orig_instance = instance;
6072 /* Dismantle the baselink to collect all the information we need. */
6073 if (!conversion_path)
6074 conversion_path = BASELINK_BINFO (fns);
6075 access_binfo = BASELINK_ACCESS_BINFO (fns);
6076 optype = BASELINK_OPTYPE (fns);
6077 fns = BASELINK_FUNCTIONS (fns);
6078 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6080 explicit_targs = TREE_OPERAND (fns, 1);
6081 fns = TREE_OPERAND (fns, 0);
6084 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6085 || TREE_CODE (fns) == TEMPLATE_DECL
6086 || TREE_CODE (fns) == OVERLOAD);
6087 fn = get_first_fn (fns);
6088 name = DECL_NAME (fn);
6090 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6091 gcc_assert (CLASS_TYPE_P (basetype));
6093 if (processing_template_decl)
6095 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6096 instance = build_non_dependent_expr (instance);
6098 make_args_non_dependent (*args);
6101 /* Figure out whether to skip the first argument for the error
6102 message we will display to users if an error occurs. We don't
6103 want to display any compiler-generated arguments. The "this"
6104 pointer hasn't been added yet. However, we must remove the VTT
6105 pointer if this is a call to a base-class constructor or
6107 skip_first_for_error = false;
6108 user_args = args == NULL ? NULL : *args;
6109 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6111 /* Callers should explicitly indicate whether they want to construct
6112 the complete object or just the part without virtual bases. */
6113 gcc_assert (name != ctor_identifier);
6114 /* Similarly for destructors. */
6115 gcc_assert (name != dtor_identifier);
6116 /* Remove the VTT pointer, if present. */
6117 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6118 && CLASSTYPE_VBASECLASSES (basetype))
6119 skip_first_for_error = true;
6122 /* Process the argument list. */
6123 if (args != NULL && *args != NULL)
6125 *args = resolve_args (*args);
6127 return error_mark_node;
6130 instance_ptr = build_this (instance);
6132 /* It's OK to call destructors and constructors on cv-qualified objects.
6133 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6135 if (DECL_DESTRUCTOR_P (fn)
6136 || DECL_CONSTRUCTOR_P (fn))
6138 tree type = build_pointer_type (basetype);
6139 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6140 instance_ptr = build_nop (type, instance_ptr);
6142 if (DECL_DESTRUCTOR_P (fn))
6143 name = complete_dtor_identifier;
6145 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6146 initializer, not T({ }). If the type doesn't have a list ctor,
6147 break apart the list into separate ctor args. */
6148 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6149 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6150 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6151 && !TYPE_HAS_LIST_CTOR (basetype))
6153 gcc_assert (VEC_length (tree, *args) == 1);
6154 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6157 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6158 first_mem_arg = instance_ptr;
6160 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6161 p = conversion_obstack_alloc (0);
6163 for (fn = fns; fn; fn = OVL_NEXT (fn))
6165 tree t = OVL_CURRENT (fn);
6166 tree this_first_arg;
6168 /* We can end up here for copy-init of same or base class. */
6169 if ((flags & LOOKUP_ONLYCONVERTING)
6170 && DECL_NONCONVERTING_P (t))
6173 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6174 this_first_arg = first_mem_arg;
6176 this_first_arg = NULL_TREE;
6178 if (TREE_CODE (t) == TEMPLATE_DECL)
6179 /* A member template. */
6180 add_template_candidate (&candidates, t,
6184 args == NULL ? NULL : *args,
6190 else if (! template_only)
6191 add_function_candidate (&candidates, t,
6194 args == NULL ? NULL : *args,
6200 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6203 if (complain & tf_error)
6205 if (!COMPLETE_TYPE_P (basetype))
6206 cxx_incomplete_type_error (instance_ptr, basetype);
6213 pretty_name = name_as_c_string (name, basetype, &free_p);
6214 arglist = build_tree_list_vec (user_args);
6215 if (skip_first_for_error)
6216 arglist = TREE_CHAIN (arglist);
6217 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6218 basetype, pretty_name, arglist,
6219 TREE_TYPE (TREE_TYPE (instance_ptr)));
6223 print_z_candidates (candidates);
6225 call = error_mark_node;
6229 cand = tourney (candidates);
6236 if (complain & tf_error)
6238 pretty_name = name_as_c_string (name, basetype, &free_p);
6239 arglist = build_tree_list_vec (user_args);
6240 if (skip_first_for_error)
6241 arglist = TREE_CHAIN (arglist);
6242 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6244 print_z_candidates (candidates);
6248 call = error_mark_node;
6254 if (!(flags & LOOKUP_NONVIRTUAL)
6255 && DECL_PURE_VIRTUAL_P (fn)
6256 && instance == current_class_ref
6257 && (DECL_CONSTRUCTOR_P (current_function_decl)
6258 || DECL_DESTRUCTOR_P (current_function_decl))
6259 && (complain & tf_warning))
6260 /* This is not an error, it is runtime undefined
6262 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6263 "abstract virtual %q#D called from constructor"
6264 : "abstract virtual %q#D called from destructor"),
6267 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6268 && is_dummy_object (instance_ptr))
6270 if (complain & tf_error)
6271 error ("cannot call member function %qD without object",
6273 call = error_mark_node;
6277 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6278 && resolves_to_fixed_type_p (instance, 0))
6279 flags |= LOOKUP_NONVIRTUAL;
6280 /* Now we know what function is being called. */
6283 /* Build the actual CALL_EXPR. */
6284 call = build_over_call (cand, flags, complain);
6285 /* In an expression of the form `a->f()' where `f' turns
6286 out to be a static member function, `a' is
6287 none-the-less evaluated. */
6288 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6289 && !is_dummy_object (instance_ptr)
6290 && TREE_SIDE_EFFECTS (instance_ptr))
6291 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6292 instance_ptr, call);
6293 else if (call != error_mark_node
6294 && DECL_DESTRUCTOR_P (cand->fn)
6295 && !VOID_TYPE_P (TREE_TYPE (call)))
6296 /* An explicit call of the form "x->~X()" has type
6297 "void". However, on platforms where destructors
6298 return "this" (i.e., those where
6299 targetm.cxx.cdtor_returns_this is true), such calls
6300 will appear to have a return value of pointer type
6301 to the low-level call machinery. We do not want to
6302 change the low-level machinery, since we want to be
6303 able to optimize "delete f()" on such platforms as
6304 "operator delete(~X(f()))" (rather than generating
6305 "t = f(), ~X(t), operator delete (t)"). */
6306 call = build_nop (void_type_node, call);
6311 if (processing_template_decl && call != error_mark_node)
6313 bool cast_to_void = false;
6315 if (TREE_CODE (call) == COMPOUND_EXPR)
6316 call = TREE_OPERAND (call, 1);
6317 else if (TREE_CODE (call) == NOP_EXPR)
6319 cast_to_void = true;
6320 call = TREE_OPERAND (call, 0);
6322 if (TREE_CODE (call) == INDIRECT_REF)
6323 call = TREE_OPERAND (call, 0);
6324 call = (build_min_non_dep_call_vec
6326 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6327 orig_instance, orig_fns, NULL_TREE),
6329 call = convert_from_reference (call);
6331 call = build_nop (void_type_node, call);
6334 /* Free all the conversions we allocated. */
6335 obstack_free (&conversion_obstack, p);
6337 if (orig_args != NULL)
6338 release_tree_vector (orig_args);
6343 /* Returns true iff standard conversion sequence ICS1 is a proper
6344 subsequence of ICS2. */
6347 is_subseq (conversion *ics1, conversion *ics2)
6349 /* We can assume that a conversion of the same code
6350 between the same types indicates a subsequence since we only get
6351 here if the types we are converting from are the same. */
6353 while (ics1->kind == ck_rvalue
6354 || ics1->kind == ck_lvalue)
6355 ics1 = ics1->u.next;
6359 while (ics2->kind == ck_rvalue
6360 || ics2->kind == ck_lvalue)
6361 ics2 = ics2->u.next;
6363 if (ics2->kind == ck_user
6364 || ics2->kind == ck_ambig
6365 || ics2->kind == ck_identity)
6366 /* At this point, ICS1 cannot be a proper subsequence of
6367 ICS2. We can get a USER_CONV when we are comparing the
6368 second standard conversion sequence of two user conversion
6372 ics2 = ics2->u.next;
6374 if (ics2->kind == ics1->kind
6375 && same_type_p (ics2->type, ics1->type)
6376 && same_type_p (ics2->u.next->type,
6377 ics1->u.next->type))
6382 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6383 be any _TYPE nodes. */
6386 is_properly_derived_from (tree derived, tree base)
6388 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6391 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6392 considers every class derived from itself. */
6393 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6394 && DERIVED_FROM_P (base, derived));
6397 /* We build the ICS for an implicit object parameter as a pointer
6398 conversion sequence. However, such a sequence should be compared
6399 as if it were a reference conversion sequence. If ICS is the
6400 implicit conversion sequence for an implicit object parameter,
6401 modify it accordingly. */
6404 maybe_handle_implicit_object (conversion **ics)
6408 /* [over.match.funcs]
6410 For non-static member functions, the type of the
6411 implicit object parameter is "reference to cv X"
6412 where X is the class of which the function is a
6413 member and cv is the cv-qualification on the member
6414 function declaration. */
6415 conversion *t = *ics;
6416 tree reference_type;
6418 /* The `this' parameter is a pointer to a class type. Make the
6419 implicit conversion talk about a reference to that same class
6421 reference_type = TREE_TYPE (t->type);
6422 reference_type = build_reference_type (reference_type);
6424 if (t->kind == ck_qual)
6426 if (t->kind == ck_ptr)
6428 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6429 t = direct_reference_binding (reference_type, t);
6431 t->rvaluedness_matches_p = 0;
6436 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6437 and return the initial reference binding conversion. Otherwise,
6438 leave *ICS unchanged and return NULL. */
6441 maybe_handle_ref_bind (conversion **ics)
6443 if ((*ics)->kind == ck_ref_bind)
6445 conversion *old_ics = *ics;
6446 *ics = old_ics->u.next;
6447 (*ics)->user_conv_p = old_ics->user_conv_p;
6448 (*ics)->bad_p = old_ics->bad_p;
6455 /* Compare two implicit conversion sequences according to the rules set out in
6456 [over.ics.rank]. Return values:
6458 1: ics1 is better than ics2
6459 -1: ics2 is better than ics1
6460 0: ics1 and ics2 are indistinguishable */
6463 compare_ics (conversion *ics1, conversion *ics2)
6469 tree deref_from_type1 = NULL_TREE;
6470 tree deref_from_type2 = NULL_TREE;
6471 tree deref_to_type1 = NULL_TREE;
6472 tree deref_to_type2 = NULL_TREE;
6473 conversion_rank rank1, rank2;
6475 /* REF_BINDING is nonzero if the result of the conversion sequence
6476 is a reference type. In that case REF_CONV is the reference
6477 binding conversion. */
6478 conversion *ref_conv1;
6479 conversion *ref_conv2;
6481 /* Handle implicit object parameters. */
6482 maybe_handle_implicit_object (&ics1);
6483 maybe_handle_implicit_object (&ics2);
6485 /* Handle reference parameters. */
6486 ref_conv1 = maybe_handle_ref_bind (&ics1);
6487 ref_conv2 = maybe_handle_ref_bind (&ics2);
6491 When comparing the basic forms of implicit conversion sequences (as
6492 defined in _over.best.ics_)
6494 --a standard conversion sequence (_over.ics.scs_) is a better
6495 conversion sequence than a user-defined conversion sequence
6496 or an ellipsis conversion sequence, and
6498 --a user-defined conversion sequence (_over.ics.user_) is a
6499 better conversion sequence than an ellipsis conversion sequence
6500 (_over.ics.ellipsis_). */
6501 rank1 = CONVERSION_RANK (ics1);
6502 rank2 = CONVERSION_RANK (ics2);
6506 else if (rank1 < rank2)
6509 if (rank1 == cr_bad)
6511 /* XXX Isn't this an extension? */
6512 /* Both ICS are bad. We try to make a decision based on what
6513 would have happened if they'd been good. */
6514 if (ics1->user_conv_p > ics2->user_conv_p
6515 || ics1->rank > ics2->rank)
6517 else if (ics1->user_conv_p < ics2->user_conv_p
6518 || ics1->rank < ics2->rank)
6521 /* We couldn't make up our minds; try to figure it out below. */
6524 if (ics1->ellipsis_p)
6525 /* Both conversions are ellipsis conversions. */
6528 /* User-defined conversion sequence U1 is a better conversion sequence
6529 than another user-defined conversion sequence U2 if they contain the
6530 same user-defined conversion operator or constructor and if the sec-
6531 ond standard conversion sequence of U1 is better than the second
6532 standard conversion sequence of U2. */
6534 if (ics1->user_conv_p)
6539 for (t1 = ics1; t1->kind != ck_user && t1->kind != ck_list; t1 = t1->u.next)
6540 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6542 for (t2 = ics2; t2->kind != ck_user && t2->kind != ck_list; t2 = t2->u.next)
6543 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6546 /* Conversion to std::initializer_list is better than other
6547 user-defined conversions. */
6548 if (t1->kind == ck_list
6549 || t2->kind == ck_list)
6551 if (t2->kind != ck_list)
6553 else if (t1->kind != ck_list)
6559 if (t1->cand->fn != t2->cand->fn)
6562 /* We can just fall through here, after setting up
6563 FROM_TYPE1 and FROM_TYPE2. */
6564 from_type1 = t1->type;
6565 from_type2 = t2->type;
6572 /* We're dealing with two standard conversion sequences.
6576 Standard conversion sequence S1 is a better conversion
6577 sequence than standard conversion sequence S2 if
6579 --S1 is a proper subsequence of S2 (comparing the conversion
6580 sequences in the canonical form defined by _over.ics.scs_,
6581 excluding any Lvalue Transformation; the identity
6582 conversion sequence is considered to be a subsequence of
6583 any non-identity conversion sequence */
6586 while (t1->kind != ck_identity)
6588 from_type1 = t1->type;
6591 while (t2->kind != ck_identity)
6593 from_type2 = t2->type;
6596 /* One sequence can only be a subsequence of the other if they start with
6597 the same type. They can start with different types when comparing the
6598 second standard conversion sequence in two user-defined conversion
6600 if (same_type_p (from_type1, from_type2))
6602 if (is_subseq (ics1, ics2))
6604 if (is_subseq (ics2, ics1))
6612 --the rank of S1 is better than the rank of S2 (by the rules
6615 Standard conversion sequences are ordered by their ranks: an Exact
6616 Match is a better conversion than a Promotion, which is a better
6617 conversion than a Conversion.
6619 Two conversion sequences with the same rank are indistinguishable
6620 unless one of the following rules applies:
6622 --A conversion that is not a conversion of a pointer, or pointer
6623 to member, to bool is better than another conversion that is such
6626 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6627 so that we do not have to check it explicitly. */
6628 if (ics1->rank < ics2->rank)
6630 else if (ics2->rank < ics1->rank)
6633 to_type1 = ics1->type;
6634 to_type2 = ics2->type;
6636 /* A conversion from scalar arithmetic type to complex is worse than a
6637 conversion between scalar arithmetic types. */
6638 if (same_type_p (from_type1, from_type2)
6639 && ARITHMETIC_TYPE_P (from_type1)
6640 && ARITHMETIC_TYPE_P (to_type1)
6641 && ARITHMETIC_TYPE_P (to_type2)
6642 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6643 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6645 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6651 if (TYPE_PTR_P (from_type1)
6652 && TYPE_PTR_P (from_type2)
6653 && TYPE_PTR_P (to_type1)
6654 && TYPE_PTR_P (to_type2))
6656 deref_from_type1 = TREE_TYPE (from_type1);
6657 deref_from_type2 = TREE_TYPE (from_type2);
6658 deref_to_type1 = TREE_TYPE (to_type1);
6659 deref_to_type2 = TREE_TYPE (to_type2);
6661 /* The rules for pointers to members A::* are just like the rules
6662 for pointers A*, except opposite: if B is derived from A then
6663 A::* converts to B::*, not vice versa. For that reason, we
6664 switch the from_ and to_ variables here. */
6665 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6666 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6667 || (TYPE_PTRMEMFUNC_P (from_type1)
6668 && TYPE_PTRMEMFUNC_P (from_type2)
6669 && TYPE_PTRMEMFUNC_P (to_type1)
6670 && TYPE_PTRMEMFUNC_P (to_type2)))
6672 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6673 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6674 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6675 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6678 if (deref_from_type1 != NULL_TREE
6679 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6680 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6682 /* This was one of the pointer or pointer-like conversions.
6686 --If class B is derived directly or indirectly from class A,
6687 conversion of B* to A* is better than conversion of B* to
6688 void*, and conversion of A* to void* is better than
6689 conversion of B* to void*. */
6690 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6691 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6693 if (is_properly_derived_from (deref_from_type1,
6696 else if (is_properly_derived_from (deref_from_type2,
6700 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6701 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6703 if (same_type_p (deref_from_type1, deref_from_type2))
6705 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6707 if (is_properly_derived_from (deref_from_type1,
6711 /* We know that DEREF_TO_TYPE1 is `void' here. */
6712 else if (is_properly_derived_from (deref_from_type1,
6717 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6718 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6722 --If class B is derived directly or indirectly from class A
6723 and class C is derived directly or indirectly from B,
6725 --conversion of C* to B* is better than conversion of C* to
6728 --conversion of B* to A* is better than conversion of C* to
6730 if (same_type_p (deref_from_type1, deref_from_type2))
6732 if (is_properly_derived_from (deref_to_type1,
6735 else if (is_properly_derived_from (deref_to_type2,
6739 else if (same_type_p (deref_to_type1, deref_to_type2))
6741 if (is_properly_derived_from (deref_from_type2,
6744 else if (is_properly_derived_from (deref_from_type1,
6750 else if (CLASS_TYPE_P (non_reference (from_type1))
6751 && same_type_p (from_type1, from_type2))
6753 tree from = non_reference (from_type1);
6757 --binding of an expression of type C to a reference of type
6758 B& is better than binding an expression of type C to a
6759 reference of type A&
6761 --conversion of C to B is better than conversion of C to A, */
6762 if (is_properly_derived_from (from, to_type1)
6763 && is_properly_derived_from (from, to_type2))
6765 if (is_properly_derived_from (to_type1, to_type2))
6767 else if (is_properly_derived_from (to_type2, to_type1))
6771 else if (CLASS_TYPE_P (non_reference (to_type1))
6772 && same_type_p (to_type1, to_type2))
6774 tree to = non_reference (to_type1);
6778 --binding of an expression of type B to a reference of type
6779 A& is better than binding an expression of type C to a
6780 reference of type A&,
6782 --conversion of B to A is better than conversion of C to A */
6783 if (is_properly_derived_from (from_type1, to)
6784 && is_properly_derived_from (from_type2, to))
6786 if (is_properly_derived_from (from_type2, from_type1))
6788 else if (is_properly_derived_from (from_type1, from_type2))
6795 --S1 and S2 differ only in their qualification conversion and yield
6796 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6797 qualification signature of type T1 is a proper subset of the cv-
6798 qualification signature of type T2 */
6799 if (ics1->kind == ck_qual
6800 && ics2->kind == ck_qual
6801 && same_type_p (from_type1, from_type2))
6803 int result = comp_cv_qual_signature (to_type1, to_type2);
6810 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6811 to an implicit object parameter, and either S1 binds an lvalue reference
6812 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6813 reference to an rvalue and S2 binds an lvalue reference
6814 (C++0x draft standard, 13.3.3.2)
6816 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6817 types to which the references refer are the same type except for
6818 top-level cv-qualifiers, and the type to which the reference
6819 initialized by S2 refers is more cv-qualified than the type to
6820 which the reference initialized by S1 refers */
6822 if (ref_conv1 && ref_conv2)
6824 if (!ref_conv1->this_p && !ref_conv2->this_p
6825 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6826 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6828 if (ref_conv1->rvaluedness_matches_p)
6830 if (ref_conv2->rvaluedness_matches_p)
6834 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6835 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6836 TREE_TYPE (ref_conv1->type));
6839 /* Neither conversion sequence is better than the other. */
6843 /* The source type for this standard conversion sequence. */
6846 source_type (conversion *t)
6848 for (;; t = t->u.next)
6850 if (t->kind == ck_user
6851 || t->kind == ck_ambig
6852 || t->kind == ck_identity)
6858 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6859 a pointer to LOSER and re-running joust to produce the warning if WINNER
6860 is actually used. */
6863 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6865 candidate_warning *cw = (candidate_warning *)
6866 conversion_obstack_alloc (sizeof (candidate_warning));
6868 cw->next = winner->warnings;
6869 winner->warnings = cw;
6872 /* Compare two candidates for overloading as described in
6873 [over.match.best]. Return values:
6875 1: cand1 is better than cand2
6876 -1: cand2 is better than cand1
6877 0: cand1 and cand2 are indistinguishable */
6880 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6883 int off1 = 0, off2 = 0;
6887 /* Candidates that involve bad conversions are always worse than those
6889 if (cand1->viable > cand2->viable)
6891 if (cand1->viable < cand2->viable)
6894 /* If we have two pseudo-candidates for conversions to the same type,
6895 or two candidates for the same function, arbitrarily pick one. */
6896 if (cand1->fn == cand2->fn
6897 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6900 /* a viable function F1
6901 is defined to be a better function than another viable function F2 if
6902 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6903 ICSi(F2), and then */
6905 /* for some argument j, ICSj(F1) is a better conversion sequence than
6908 /* For comparing static and non-static member functions, we ignore
6909 the implicit object parameter of the non-static function. The
6910 standard says to pretend that the static function has an object
6911 parm, but that won't work with operator overloading. */
6912 len = cand1->num_convs;
6913 if (len != cand2->num_convs)
6915 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6916 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6918 gcc_assert (static_1 != static_2);
6929 for (i = 0; i < len; ++i)
6931 conversion *t1 = cand1->convs[i + off1];
6932 conversion *t2 = cand2->convs[i + off2];
6933 int comp = compare_ics (t1, t2);
6938 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6939 == cr_std + cr_promotion)
6940 && t1->kind == ck_std
6941 && t2->kind == ck_std
6942 && TREE_CODE (t1->type) == INTEGER_TYPE
6943 && TREE_CODE (t2->type) == INTEGER_TYPE
6944 && (TYPE_PRECISION (t1->type)
6945 == TYPE_PRECISION (t2->type))
6946 && (TYPE_UNSIGNED (t1->u.next->type)
6947 || (TREE_CODE (t1->u.next->type)
6950 tree type = t1->u.next->type;
6952 struct z_candidate *w, *l;
6954 type1 = t1->type, type2 = t2->type,
6955 w = cand1, l = cand2;
6957 type1 = t2->type, type2 = t1->type,
6958 w = cand2, l = cand1;
6962 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6963 type, type1, type2);
6964 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6970 if (winner && comp != winner)
6979 /* warn about confusing overload resolution for user-defined conversions,
6980 either between a constructor and a conversion op, or between two
6982 if (winner && warn_conversion && cand1->second_conv
6983 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6984 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6986 struct z_candidate *w, *l;
6987 bool give_warning = false;
6990 w = cand1, l = cand2;
6992 w = cand2, l = cand1;
6994 /* We don't want to complain about `X::operator T1 ()'
6995 beating `X::operator T2 () const', when T2 is a no less
6996 cv-qualified version of T1. */
6997 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6998 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7000 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7001 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7003 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7008 if (!comp_ptr_ttypes (t, f))
7009 give_warning = true;
7012 give_warning = true;
7018 tree source = source_type (w->convs[0]);
7019 if (! DECL_CONSTRUCTOR_P (w->fn))
7020 source = TREE_TYPE (source);
7021 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7022 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7023 source, w->second_conv->type))
7025 inform (input_location, " because conversion sequence for the argument is better");
7036 F1 is a non-template function and F2 is a template function
7039 if (!cand1->template_decl && cand2->template_decl)
7041 else if (cand1->template_decl && !cand2->template_decl)
7045 F1 and F2 are template functions and the function template for F1 is
7046 more specialized than the template for F2 according to the partial
7049 if (cand1->template_decl && cand2->template_decl)
7051 winner = more_specialized_fn
7052 (TI_TEMPLATE (cand1->template_decl),
7053 TI_TEMPLATE (cand2->template_decl),
7054 /* [temp.func.order]: The presence of unused ellipsis and default
7055 arguments has no effect on the partial ordering of function
7056 templates. add_function_candidate() will not have
7057 counted the "this" argument for constructors. */
7058 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
7064 the context is an initialization by user-defined conversion (see
7065 _dcl.init_ and _over.match.user_) and the standard conversion
7066 sequence from the return type of F1 to the destination type (i.e.,
7067 the type of the entity being initialized) is a better conversion
7068 sequence than the standard conversion sequence from the return type
7069 of F2 to the destination type. */
7071 if (cand1->second_conv)
7073 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7078 /* Check whether we can discard a builtin candidate, either because we
7079 have two identical ones or matching builtin and non-builtin candidates.
7081 (Pedantically in the latter case the builtin which matched the user
7082 function should not be added to the overload set, but we spot it here.
7085 ... the builtin candidates include ...
7086 - do not have the same parameter type list as any non-template
7087 non-member candidate. */
7089 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7090 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7092 for (i = 0; i < len; ++i)
7093 if (!same_type_p (cand1->convs[i]->type,
7094 cand2->convs[i]->type))
7096 if (i == cand1->num_convs)
7098 if (cand1->fn == cand2->fn)
7099 /* Two built-in candidates; arbitrarily pick one. */
7101 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7102 /* cand1 is built-in; prefer cand2. */
7105 /* cand2 is built-in; prefer cand1. */
7110 /* If the two function declarations represent the same function (this can
7111 happen with declarations in multiple scopes and arg-dependent lookup),
7112 arbitrarily choose one. But first make sure the default args we're
7114 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7115 && equal_functions (cand1->fn, cand2->fn))
7117 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7118 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7120 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7122 for (i = 0; i < len; ++i)
7124 /* Don't crash if the fn is variadic. */
7127 parms1 = TREE_CHAIN (parms1);
7128 parms2 = TREE_CHAIN (parms2);
7132 parms1 = TREE_CHAIN (parms1);
7134 parms2 = TREE_CHAIN (parms2);
7138 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7139 TREE_PURPOSE (parms2)))
7143 permerror (input_location, "default argument mismatch in "
7144 "overload resolution");
7145 inform (input_location,
7146 " candidate 1: %q+#F", cand1->fn);
7147 inform (input_location,
7148 " candidate 2: %q+#F", cand2->fn);
7151 add_warning (cand1, cand2);
7154 parms1 = TREE_CHAIN (parms1);
7155 parms2 = TREE_CHAIN (parms2);
7163 /* Extension: If the worst conversion for one candidate is worse than the
7164 worst conversion for the other, take the first. */
7167 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7168 struct z_candidate *w = 0, *l = 0;
7170 for (i = 0; i < len; ++i)
7172 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7173 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7174 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7175 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7178 winner = 1, w = cand1, l = cand2;
7180 winner = -1, w = cand2, l = cand1;
7185 pedwarn (input_location, 0,
7186 "ISO C++ says that these are ambiguous, even "
7187 "though the worst conversion for the first is better than "
7188 "the worst conversion for the second:");
7189 print_z_candidate (_("candidate 1:"), w);
7190 print_z_candidate (_("candidate 2:"), l);
7198 gcc_assert (!winner);
7202 /* Given a list of candidates for overloading, find the best one, if any.
7203 This algorithm has a worst case of O(2n) (winner is last), and a best
7204 case of O(n/2) (totally ambiguous); much better than a sorting
7207 static struct z_candidate *
7208 tourney (struct z_candidate *candidates)
7210 struct z_candidate *champ = candidates, *challenger;
7212 int champ_compared_to_predecessor = 0;
7214 /* Walk through the list once, comparing each current champ to the next
7215 candidate, knocking out a candidate or two with each comparison. */
7217 for (challenger = champ->next; challenger; )
7219 fate = joust (champ, challenger, 0);
7221 challenger = challenger->next;
7226 champ = challenger->next;
7229 champ_compared_to_predecessor = 0;
7234 champ_compared_to_predecessor = 1;
7237 challenger = champ->next;
7241 /* Make sure the champ is better than all the candidates it hasn't yet
7242 been compared to. */
7244 for (challenger = candidates;
7246 && !(champ_compared_to_predecessor && challenger->next == champ);
7247 challenger = challenger->next)
7249 fate = joust (champ, challenger, 0);
7257 /* Returns nonzero if things of type FROM can be converted to TO. */
7260 can_convert (tree to, tree from)
7262 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
7265 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7268 can_convert_arg (tree to, tree from, tree arg, int flags)
7274 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7275 p = conversion_obstack_alloc (0);
7277 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7279 ok_p = (t && !t->bad_p);
7281 /* Free all the conversions we allocated. */
7282 obstack_free (&conversion_obstack, p);
7287 /* Like can_convert_arg, but allows dubious conversions as well. */
7290 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
7295 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7296 p = conversion_obstack_alloc (0);
7297 /* Try to perform the conversion. */
7298 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7300 /* Free all the conversions we allocated. */
7301 obstack_free (&conversion_obstack, p);
7306 /* Convert EXPR to TYPE. Return the converted expression.
7308 Note that we allow bad conversions here because by the time we get to
7309 this point we are committed to doing the conversion. If we end up
7310 doing a bad conversion, convert_like will complain. */
7313 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7318 if (error_operand_p (expr))
7319 return error_mark_node;
7321 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7322 p = conversion_obstack_alloc (0);
7324 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7330 if (complain & tf_error)
7332 /* If expr has unknown type, then it is an overloaded function.
7333 Call instantiate_type to get good error messages. */
7334 if (TREE_TYPE (expr) == unknown_type_node)
7335 instantiate_type (type, expr, complain);
7336 else if (invalid_nonstatic_memfn_p (expr, complain))
7337 /* We gave an error. */;
7339 error ("could not convert %qE to %qT", expr, type);
7341 expr = error_mark_node;
7343 else if (processing_template_decl)
7345 /* In a template, we are only concerned about determining the
7346 type of non-dependent expressions, so we do not have to
7347 perform the actual conversion. */
7348 if (TREE_TYPE (expr) != type)
7349 expr = build_nop (type, expr);
7352 expr = convert_like (conv, expr, complain);
7354 /* Free all the conversions we allocated. */
7355 obstack_free (&conversion_obstack, p);
7361 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7363 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7366 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7367 permitted. If the conversion is valid, the converted expression is
7368 returned. Otherwise, NULL_TREE is returned, except in the case
7369 that TYPE is a class type; in that case, an error is issued. If
7370 C_CAST_P is true, then this direction initialization is taking
7371 place as part of a static_cast being attempted as part of a C-style
7375 perform_direct_initialization_if_possible (tree type,
7378 tsubst_flags_t complain)
7383 if (type == error_mark_node || error_operand_p (expr))
7384 return error_mark_node;
7387 If the destination type is a (possibly cv-qualified) class type:
7389 -- If the initialization is direct-initialization ...,
7390 constructors are considered. ... If no constructor applies, or
7391 the overload resolution is ambiguous, the initialization is
7393 if (CLASS_TYPE_P (type))
7395 VEC(tree,gc) *args = make_tree_vector_single (expr);
7396 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7397 &args, type, LOOKUP_NORMAL, complain);
7398 release_tree_vector (args);
7399 return build_cplus_new (type, expr);
7402 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7403 p = conversion_obstack_alloc (0);
7405 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7408 if (!conv || conv->bad_p)
7411 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7412 /*issue_conversion_warnings=*/false,
7414 tf_warning_or_error);
7416 /* Free all the conversions we allocated. */
7417 obstack_free (&conversion_obstack, p);
7422 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7423 is being bound to a temporary. Create and return a new VAR_DECL
7424 with the indicated TYPE; this variable will store the value to
7425 which the reference is bound. */
7428 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7432 /* Create the variable. */
7433 var = create_temporary_var (type);
7435 /* Register the variable. */
7436 if (TREE_STATIC (decl))
7438 /* Namespace-scope or local static; give it a mangled name. */
7441 TREE_STATIC (var) = 1;
7442 name = mangle_ref_init_variable (decl);
7443 DECL_NAME (var) = name;
7444 SET_DECL_ASSEMBLER_NAME (var, name);
7445 var = pushdecl_top_level (var);
7448 /* Create a new cleanup level if necessary. */
7449 maybe_push_cleanup_level (type);
7454 /* EXPR is the initializer for a variable DECL of reference or
7455 std::initializer_list type. Create, push and return a new VAR_DECL
7456 for the initializer so that it will live as long as DECL. Any
7457 cleanup for the new variable is returned through CLEANUP, and the
7458 code to initialize the new variable is returned through INITP. */
7461 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7467 /* Create the temporary variable. */
7468 type = TREE_TYPE (expr);
7469 var = make_temporary_var_for_ref_to_temp (decl, type);
7470 layout_decl (var, 0);
7471 /* If the rvalue is the result of a function call it will be
7472 a TARGET_EXPR. If it is some other construct (such as a
7473 member access expression where the underlying object is
7474 itself the result of a function call), turn it into a
7475 TARGET_EXPR here. It is important that EXPR be a
7476 TARGET_EXPR below since otherwise the INIT_EXPR will
7477 attempt to make a bitwise copy of EXPR to initialize
7479 if (TREE_CODE (expr) != TARGET_EXPR)
7480 expr = get_target_expr (expr);
7481 /* Create the INIT_EXPR that will initialize the temporary
7483 init = build2 (INIT_EXPR, type, var, expr);
7484 if (at_function_scope_p ())
7486 add_decl_expr (var);
7488 if (TREE_STATIC (var))
7489 init = add_stmt_to_compound (init, register_dtor_fn (var));
7491 *cleanup = cxx_maybe_build_cleanup (var);
7493 /* We must be careful to destroy the temporary only
7494 after its initialization has taken place. If the
7495 initialization throws an exception, then the
7496 destructor should not be run. We cannot simply
7497 transform INIT into something like:
7499 (INIT, ({ CLEANUP_STMT; }))
7501 because emit_local_var always treats the
7502 initializer as a full-expression. Thus, the
7503 destructor would run too early; it would run at the
7504 end of initializing the reference variable, rather
7505 than at the end of the block enclosing the
7508 The solution is to pass back a cleanup expression
7509 which the caller is responsible for attaching to
7510 the statement tree. */
7514 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7515 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7516 static_aggregates = tree_cons (NULL_TREE, var,
7524 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7525 initializing a variable of that TYPE. If DECL is non-NULL, it is
7526 the VAR_DECL being initialized with the EXPR. (In that case, the
7527 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7528 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7529 return, if *CLEANUP is no longer NULL, it will be an expression
7530 that should be pushed as a cleanup after the returned expression
7531 is used to initialize DECL.
7533 Return the converted expression. */
7536 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7541 if (type == error_mark_node || error_operand_p (expr))
7542 return error_mark_node;
7544 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7545 p = conversion_obstack_alloc (0);
7547 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7549 if (!conv || conv->bad_p)
7551 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7552 && !real_lvalue_p (expr))
7553 error ("invalid initialization of non-const reference of "
7554 "type %qT from a temporary of type %qT",
7555 type, TREE_TYPE (expr));
7557 error ("invalid initialization of reference of type "
7558 "%qT from expression of type %qT", type,
7560 return error_mark_node;
7563 /* If DECL is non-NULL, then this special rule applies:
7567 The temporary to which the reference is bound or the temporary
7568 that is the complete object to which the reference is bound
7569 persists for the lifetime of the reference.
7571 The temporaries created during the evaluation of the expression
7572 initializing the reference, except the temporary to which the
7573 reference is bound, are destroyed at the end of the
7574 full-expression in which they are created.
7576 In that case, we store the converted expression into a new
7577 VAR_DECL in a new scope.
7579 However, we want to be careful not to create temporaries when
7580 they are not required. For example, given:
7583 struct D : public B {};
7587 there is no need to copy the return value from "f"; we can just
7588 extend its lifetime. Similarly, given:
7591 struct T { operator S(); };
7595 we can extend the lifetime of the return value of the conversion
7597 gcc_assert (conv->kind == ck_ref_bind);
7601 tree base_conv_type;
7603 /* Skip over the REF_BIND. */
7604 conv = conv->u.next;
7605 /* If the next conversion is a BASE_CONV, skip that too -- but
7606 remember that the conversion was required. */
7607 if (conv->kind == ck_base)
7609 base_conv_type = conv->type;
7610 conv = conv->u.next;
7613 base_conv_type = NULL_TREE;
7614 /* Perform the remainder of the conversion. */
7615 expr = convert_like_real (conv, expr,
7616 /*fn=*/NULL_TREE, /*argnum=*/0,
7618 /*issue_conversion_warnings=*/true,
7620 tf_warning_or_error);
7621 if (error_operand_p (expr))
7622 expr = error_mark_node;
7625 if (!real_lvalue_p (expr))
7628 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7629 /* Use its address to initialize the reference variable. */
7630 expr = build_address (var);
7632 expr = convert_to_base (expr,
7633 build_pointer_type (base_conv_type),
7634 /*check_access=*/true,
7636 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7639 /* Take the address of EXPR. */
7640 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7641 /* If a BASE_CONV was required, perform it now. */
7643 expr = (perform_implicit_conversion
7644 (build_pointer_type (base_conv_type), expr,
7645 tf_warning_or_error));
7646 expr = build_nop (type, expr);
7650 /* Perform the conversion. */
7651 expr = convert_like (conv, expr, tf_warning_or_error);
7653 /* Free all the conversions we allocated. */
7654 obstack_free (&conversion_obstack, p);
7659 /* Returns true iff TYPE is some variant of std::initializer_list. */
7662 is_std_init_list (tree type)
7664 return (CLASS_TYPE_P (type)
7665 && CP_TYPE_CONTEXT (type) == std_node
7666 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7669 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7670 will accept an argument list of a single std::initializer_list<T>. */
7673 is_list_ctor (tree decl)
7675 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7678 if (!args || args == void_list_node)
7681 arg = non_reference (TREE_VALUE (args));
7682 if (!is_std_init_list (arg))
7685 args = TREE_CHAIN (args);
7687 if (args && args != void_list_node && !TREE_PURPOSE (args))
7688 /* There are more non-defaulted parms. */
7694 #include "gt-cp-call.h"